diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst
index c0f2c7586531..b7dcc86c92a4 100644
--- a/Documentation/filesystems/locking.rst
+++ b/Documentation/filesystems/locking.rst
@@ -126,9 +126,10 @@ prototypes::
 	int (*get)(const struct xattr_handler *handler, struct dentry *dentry,
 		   struct inode *inode, const char *name, void *buffer,
 		   size_t size);
-	int (*set)(const struct xattr_handler *handler, struct dentry *dentry,
-		   struct inode *inode, const char *name, const void *buffer,
-		   size_t size, int flags);
+	int (*set)(const struct xattr_handler *handler,
+                   struct user_namespace *mnt_userns,
+                   struct dentry *dentry, struct inode *inode, const char *name,
+                   const void *buffer, size_t size, int flags);
 
 locking rules:
 	all may block
diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst
index 1f8cf8e10b34..633610253f45 100644
--- a/Documentation/filesystems/porting.rst
+++ b/Documentation/filesystems/porting.rst
@@ -717,6 +717,8 @@ be removed.  Switch while you still can; the old one won't stay.
 **mandatory**
 
 ->setxattr() and xattr_handler.set() get dentry and inode passed separately.
+The xattr_handler.set() gets passed the user namespace of the mount the inode
+is seen from so filesystems can idmap the i_uid and i_gid accordingly.
 dentry might be yet to be attached to inode, so do _not_ use its ->d_inode
 in the instances.  Rationale: !@#!@# security_d_instantiate() needs to be
 called before we attach dentry to inode and !@#!@##!@$!$#!@#$!@$!@$ smack
diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst
index a4d64b1b4295..2049bbf5e388 100644
--- a/Documentation/filesystems/vfs.rst
+++ b/Documentation/filesystems/vfs.rst
@@ -418,28 +418,29 @@ As of kernel 2.6.22, the following members are defined:
 .. code-block:: c
 
 	struct inode_operations {
-		int (*create) (struct inode *,struct dentry *, umode_t, bool);
+		int (*create) (struct user_namespace *, struct inode *,struct dentry *, umode_t, bool);
 		struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
 		int (*link) (struct dentry *,struct inode *,struct dentry *);
 		int (*unlink) (struct inode *,struct dentry *);
-		int (*symlink) (struct inode *,struct dentry *,const char *);
-		int (*mkdir) (struct inode *,struct dentry *,umode_t);
+		int (*symlink) (struct user_namespace *, struct inode *,struct dentry *,const char *);
+		int (*mkdir) (struct user_namespace *, struct inode *,struct dentry *,umode_t);
 		int (*rmdir) (struct inode *,struct dentry *);
-		int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
-		int (*rename) (struct inode *, struct dentry *,
+		int (*mknod) (struct user_namespace *, struct inode *,struct dentry *,umode_t,dev_t);
+		int (*rename) (struct user_namespace *, struct inode *, struct dentry *,
 			       struct inode *, struct dentry *, unsigned int);
 		int (*readlink) (struct dentry *, char __user *,int);
 		const char *(*get_link) (struct dentry *, struct inode *,
 					 struct delayed_call *);
-		int (*permission) (struct inode *, int);
+		int (*permission) (struct user_namespace *, struct inode *, int);
 		int (*get_acl)(struct inode *, int);
-		int (*setattr) (struct dentry *, struct iattr *);
-		int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
+		int (*setattr) (struct user_namespace *, struct dentry *, struct iattr *);
+		int (*getattr) (struct user_namespace *, const struct path *, struct kstat *, u32, unsigned int);
 		ssize_t (*listxattr) (struct dentry *, char *, size_t);
 		void (*update_time)(struct inode *, struct timespec *, int);
 		int (*atomic_open)(struct inode *, struct dentry *, struct file *,
 				   unsigned open_flag, umode_t create_mode);
-		int (*tmpfile) (struct inode *, struct dentry *, umode_t);
+		int (*tmpfile) (struct user_namespace *, struct inode *, struct dentry *, umode_t);
+	        int (*set_acl)(struct user_namespace *, struct inode *, struct posix_acl *, int);
 	};
 
 Again, all methods are called without any locks being held, unless
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index a6617067dbe6..02f0244e005c 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -481,3 +481,4 @@
 549	common	faccessat2			sys_faccessat2
 550	common	process_madvise			sys_process_madvise
 551	common	epoll_pwait2			sys_epoll_pwait2
+552	common	mount_setattr			sys_mount_setattr
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index 20e1170e2e0a..dcc1191291a2 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -455,3 +455,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index 86a9d7b3eabe..949788f5ba40 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -38,7 +38,7 @@
 #define __ARM_NR_compat_set_tls		(__ARM_NR_COMPAT_BASE + 5)
 #define __ARM_NR_COMPAT_END		(__ARM_NR_COMPAT_BASE + 0x800)
 
-#define __NR_compat_syscalls		442
+#define __NR_compat_syscalls		443
 #endif
 
 #define __ARCH_WANT_SYS_CLONE
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index cccfbbefbf95..3d874f624056 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -891,6 +891,8 @@ __SYSCALL(__NR_faccessat2, sys_faccessat2)
 __SYSCALL(__NR_process_madvise, sys_process_madvise)
 #define __NR_epoll_pwait2 441
 __SYSCALL(__NR_epoll_pwait2, compat_sys_epoll_pwait2)
+#define __NR_mount_setattr 442
+__SYSCALL(__NR_mount_setattr, sys_mount_setattr)
 
 /*
  * Please add new compat syscalls above this comment and update
diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/syscalls/syscall.tbl
index bfc00f2bd437..d89231166e19 100644
--- a/arch/ia64/kernel/syscalls/syscall.tbl
+++ b/arch/ia64/kernel/syscalls/syscall.tbl
@@ -362,3 +362,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index 7fe4e45c864c..72bde6707dd3 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -441,3 +441,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index a522adf194ab..d603a5ec9338 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -447,3 +447,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index 0f03ad223f33..8fd8c1790941 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -380,3 +380,4 @@
 439	n32	faccessat2			sys_faccessat2
 440	n32	process_madvise			sys_process_madvise
 441	n32	epoll_pwait2			compat_sys_epoll_pwait2
+442	n32	mount_setattr			sys_mount_setattr
diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl
index 91649690b52f..169f21438065 100644
--- a/arch/mips/kernel/syscalls/syscall_n64.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n64.tbl
@@ -356,3 +356,4 @@
 439	n64	faccessat2			sys_faccessat2
 440	n64	process_madvise			sys_process_madvise
 441	n64	epoll_pwait2			sys_epoll_pwait2
+442	n64	mount_setattr			sys_mount_setattr
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 4bad0c40aed6..090d29ca80ff 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -429,3 +429,4 @@
 439	o32	faccessat2			sys_faccessat2
 440	o32	process_madvise			sys_process_madvise
 441	o32	epoll_pwait2			sys_epoll_pwait2		compat_sys_epoll_pwait2
+442	o32	mount_setattr			sys_mount_setattr
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index 6bcc31966b44..271a92519683 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -439,3 +439,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2		compat_sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index 96b2157f0371..0b2480cf3e47 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -521,3 +521,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2		compat_sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c
index 25390569e24c..b83a3670bd74 100644
--- a/arch/powerpc/platforms/cell/spufs/inode.c
+++ b/arch/powerpc/platforms/cell/spufs/inode.c
@@ -91,14 +91,15 @@ out:
 }
 
 static int
-spufs_setattr(struct dentry *dentry, struct iattr *attr)
+spufs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+	      struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 
 	if ((attr->ia_valid & ATTR_SIZE) &&
 	    (attr->ia_size != inode->i_size))
 		return -EINVAL;
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index d443423495e5..3abef2144dac 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -444,3 +444,4 @@
 439  common	faccessat2		sys_faccessat2			sys_faccessat2
 440  common	process_madvise		sys_process_madvise		sys_process_madvise
 441  common	epoll_pwait2		sys_epoll_pwait2		compat_sys_epoll_pwait2
+442  common	mount_setattr		sys_mount_setattr		sys_mount_setattr
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index 9df40ac0ebc0..d08eebad6b7f 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -444,3 +444,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 40d8c7cd8298..84403a99039c 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -487,3 +487,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2		compat_sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 874aeacde2dd..a1c9f496fca6 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -446,3 +446,4 @@
 439	i386	faccessat2		sys_faccessat2
 440	i386	process_madvise		sys_process_madvise
 441	i386	epoll_pwait2		sys_epoll_pwait2		compat_sys_epoll_pwait2
+442	i386	mount_setattr		sys_mount_setattr
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 78672124d28b..7bf01cbe582f 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -363,6 +363,7 @@
 439	common	faccessat2		sys_faccessat2
 440	common	process_madvise		sys_process_madvise
 441	common	epoll_pwait2		sys_epoll_pwait2
+442	common	mount_setattr		sys_mount_setattr
 
 #
 # Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index 46116a28eeed..365a9b849224 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -412,3 +412,4 @@
 439	common	faccessat2			sys_faccessat2
 440	common	process_madvise			sys_process_madvise
 441	common	epoll_pwait2			sys_epoll_pwait2
+442	common	mount_setattr			sys_mount_setattr
diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c
index 7b4f154f07e6..e80ba93c62a9 100644
--- a/drivers/android/binderfs.c
+++ b/drivers/android/binderfs.c
@@ -355,7 +355,8 @@ static inline bool is_binderfs_control_device(const struct dentry *dentry)
 	return info->control_dentry == dentry;
 }
 
-static int binderfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+static int binderfs_rename(struct user_namespace *mnt_userns,
+			   struct inode *old_dir, struct dentry *old_dentry,
 			   struct inode *new_dir, struct dentry *new_dentry,
 			   unsigned int flags)
 {
@@ -363,7 +364,8 @@ static int binderfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	    is_binderfs_control_device(new_dentry))
 		return -EPERM;
 
-	return simple_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
+	return simple_rename(&init_user_ns, old_dir, old_dentry, new_dir,
+			     new_dentry, flags);
 }
 
 static int binderfs_unlink(struct inode *dir, struct dentry *dentry)
diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index eac184e6d657..653c8c6ac7a7 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -162,7 +162,7 @@ static int dev_mkdir(const char *name, umode_t mode)
 	if (IS_ERR(dentry))
 		return PTR_ERR(dentry);
 
-	err = vfs_mkdir(d_inode(path.dentry), dentry, mode);
+	err = vfs_mkdir(&init_user_ns, d_inode(path.dentry), dentry, mode);
 	if (!err)
 		/* mark as kernel-created inode */
 		d_inode(dentry)->i_private = &thread;
@@ -212,7 +212,8 @@ static int handle_create(const char *nodename, umode_t mode, kuid_t uid,
 	if (IS_ERR(dentry))
 		return PTR_ERR(dentry);
 
-	err = vfs_mknod(d_inode(path.dentry), dentry, mode, dev->devt);
+	err = vfs_mknod(&init_user_ns, d_inode(path.dentry), dentry, mode,
+			dev->devt);
 	if (!err) {
 		struct iattr newattrs;
 
@@ -221,7 +222,7 @@ static int handle_create(const char *nodename, umode_t mode, kuid_t uid,
 		newattrs.ia_gid = gid;
 		newattrs.ia_valid = ATTR_MODE|ATTR_UID|ATTR_GID;
 		inode_lock(d_inode(dentry));
-		notify_change(dentry, &newattrs, NULL);
+		notify_change(&init_user_ns, dentry, &newattrs, NULL);
 		inode_unlock(d_inode(dentry));
 
 		/* mark as kernel-created inode */
@@ -242,7 +243,8 @@ static int dev_rmdir(const char *name)
 		return PTR_ERR(dentry);
 	if (d_really_is_positive(dentry)) {
 		if (d_inode(dentry)->i_private == &thread)
-			err = vfs_rmdir(d_inode(parent.dentry), dentry);
+			err = vfs_rmdir(&init_user_ns, d_inode(parent.dentry),
+					dentry);
 		else
 			err = -EPERM;
 	} else {
@@ -328,9 +330,10 @@ static int handle_remove(const char *nodename, struct device *dev)
 			newattrs.ia_valid =
 				ATTR_UID|ATTR_GID|ATTR_MODE;
 			inode_lock(d_inode(dentry));
-			notify_change(dentry, &newattrs, NULL);
+			notify_change(&init_user_ns, dentry, &newattrs, NULL);
 			inode_unlock(d_inode(dentry));
-			err = vfs_unlink(d_inode(parent.dentry), dentry, NULL);
+			err = vfs_unlink(&init_user_ns, d_inode(parent.dentry),
+					 dentry, NULL);
 			if (!err || err == -ENOENT)
 				deleted = 1;
 		}
diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index 6261719f6f2a..bb1b286c49ae 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -239,6 +239,7 @@ static int v9fs_xattr_get_acl(const struct xattr_handler *handler,
 }
 
 static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
+			      struct user_namespace *mnt_userns,
 			      struct dentry *dentry, struct inode *inode,
 			      const char *name, const void *value,
 			      size_t size, int flags)
@@ -258,7 +259,7 @@ static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
 
 	if (S_ISLNK(inode->i_mode))
 		return -EOPNOTSUPP;
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EPERM;
 	if (value) {
 		/* update the cached acl value */
@@ -279,7 +280,8 @@ static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
 			struct iattr iattr = { 0 };
 			struct posix_acl *old_acl = acl;
 
-			retval = posix_acl_update_mode(inode, &iattr.ia_mode, &acl);
+			retval = posix_acl_update_mode(&init_user_ns, inode,
+						       &iattr.ia_mode, &acl);
 			if (retval)
 				goto err_out;
 			if (!acl) {
@@ -297,7 +299,7 @@ static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
 			 * What is the following setxattr update the
 			 * mode ?
 			 */
-			v9fs_vfs_setattr_dotl(dentry, &iattr);
+			v9fs_vfs_setattr_dotl(&init_user_ns, dentry, &iattr);
 		}
 		break;
 	case ACL_TYPE_DEFAULT:
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index 7b763776306e..4ca56c5dd637 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -135,7 +135,8 @@ extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 			unsigned int flags);
 extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d);
 extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d);
-extern int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+extern int v9fs_vfs_rename(struct user_namespace *mnt_userns,
+			   struct inode *old_dir, struct dentry *old_dentry,
 			   struct inode *new_dir, struct dentry *new_dentry,
 			   unsigned int flags);
 extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index fd2a2b040250..d44ade76966a 100644
--- a/fs/9p/v9fs_vfs.h
+++ b/fs/9p/v9fs_vfs.h
@@ -59,7 +59,8 @@ void v9fs_inode2stat(struct inode *inode, struct p9_wstat *stat);
 int v9fs_uflags2omode(int uflags, int extended);
 
 void v9fs_blank_wstat(struct p9_wstat *wstat);
-int v9fs_vfs_setattr_dotl(struct dentry *, struct iattr *);
+int v9fs_vfs_setattr_dotl(struct user_namespace *, struct dentry *,
+			  struct iattr *);
 int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
 			 int datasync);
 int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode);
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 4a937fac1acb..648eb4c4cf7f 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -251,7 +251,7 @@ int v9fs_init_inode(struct v9fs_session_info *v9ses,
 {
 	int err = 0;
 
-	inode_init_owner(inode, NULL, mode);
+	inode_init_owner(&init_user_ns,inode,  NULL, mode);
 	inode->i_blocks = 0;
 	inode->i_rdev = rdev;
 	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
@@ -676,8 +676,8 @@ error:
  */
 
 static int
-v9fs_vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		bool excl)
+v9fs_vfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
 	u32 perm = unixmode2p9mode(v9ses, mode);
@@ -702,7 +702,8 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
  *
  */
 
-static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int v9fs_vfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode)
 {
 	int err;
 	u32 perm;
@@ -907,9 +908,9 @@ int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
  */
 
 int
-v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		struct inode *new_dir, struct dentry *new_dentry,
-		unsigned int flags)
+v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		struct dentry *old_dentry, struct inode *new_dir,
+		struct dentry *new_dentry, unsigned int flags)
 {
 	int retval;
 	struct inode *old_inode;
@@ -1016,8 +1017,8 @@ done:
  */
 
 static int
-v9fs_vfs_getattr(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int flags)
+v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct dentry *dentry = path->dentry;
 	struct v9fs_session_info *v9ses;
@@ -1027,7 +1028,7 @@ v9fs_vfs_getattr(const struct path *path, struct kstat *stat,
 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 	v9ses = v9fs_dentry2v9ses(dentry);
 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
-		generic_fillattr(d_inode(dentry), stat);
+		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
 		return 0;
 	}
 	fid = v9fs_fid_lookup(dentry);
@@ -1040,7 +1041,7 @@ v9fs_vfs_getattr(const struct path *path, struct kstat *stat,
 		return PTR_ERR(st);
 
 	v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);
-	generic_fillattr(d_inode(dentry), stat);
+	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
 
 	p9stat_free(st);
 	kfree(st);
@@ -1054,7 +1055,8 @@ v9fs_vfs_getattr(const struct path *path, struct kstat *stat,
  *
  */
 
-static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
+static int v9fs_vfs_setattr(struct user_namespace *mnt_userns,
+			    struct dentry *dentry, struct iattr *iattr)
 {
 	int retval, use_dentry = 0;
 	struct v9fs_session_info *v9ses;
@@ -1062,7 +1064,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	struct p9_wstat wstat;
 
 	p9_debug(P9_DEBUG_VFS, "\n");
-	retval = setattr_prepare(dentry, iattr);
+	retval = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (retval)
 		return retval;
 
@@ -1118,7 +1120,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 
 	v9fs_invalidate_inode_attr(d_inode(dentry));
 
-	setattr_copy(d_inode(dentry), iattr);
+	setattr_copy(&init_user_ns, d_inode(dentry), iattr);
 	mark_inode_dirty(d_inode(dentry));
 	return 0;
 }
@@ -1295,7 +1297,8 @@ static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
  */
 
 static int
-v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+v9fs_vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		 struct dentry *dentry, const char *symname)
 {
 	p9_debug(P9_DEBUG_VFS, " %lu,%pd,%s\n",
 		 dir->i_ino, dentry, symname);
@@ -1348,7 +1351,8 @@ v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
  */
 
 static int
-v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
+v9fs_vfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+	       struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
 	int retval;
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 823c2eb5f1bf..1dc7af046615 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -33,8 +33,8 @@
 #include "acl.h"
 
 static int
-v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
-		    dev_t rdev);
+v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
+		    struct dentry *dentry, umode_t omode, dev_t rdev);
 
 /**
  * v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
@@ -218,10 +218,10 @@ int v9fs_open_to_dotl_flags(int flags)
  */
 
 static int
-v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
-		bool excl)
+v9fs_vfs_create_dotl(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t omode, bool excl)
 {
-	return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
+	return v9fs_vfs_mknod_dotl(mnt_userns, dir, dentry, omode, 0);
 }
 
 static int
@@ -367,8 +367,9 @@ err_clunk_old_fid:
  *
  */
 
-static int v9fs_vfs_mkdir_dotl(struct inode *dir,
-			       struct dentry *dentry, umode_t omode)
+static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns,
+			       struct inode *dir, struct dentry *dentry,
+			       umode_t omode)
 {
 	int err;
 	struct v9fs_session_info *v9ses;
@@ -457,8 +458,9 @@ error:
 }
 
 static int
-v9fs_vfs_getattr_dotl(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int flags)
+v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,
+		      const struct path *path, struct kstat *stat,
+		      u32 request_mask, unsigned int flags)
 {
 	struct dentry *dentry = path->dentry;
 	struct v9fs_session_info *v9ses;
@@ -468,7 +470,7 @@ v9fs_vfs_getattr_dotl(const struct path *path, struct kstat *stat,
 	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 	v9ses = v9fs_dentry2v9ses(dentry);
 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
-		generic_fillattr(d_inode(dentry), stat);
+		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
 		return 0;
 	}
 	fid = v9fs_fid_lookup(dentry);
@@ -485,7 +487,7 @@ v9fs_vfs_getattr_dotl(const struct path *path, struct kstat *stat,
 		return PTR_ERR(st);
 
 	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
-	generic_fillattr(d_inode(dentry), stat);
+	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
 	/* Change block size to what the server returned */
 	stat->blksize = st->st_blksize;
 
@@ -540,7 +542,8 @@ static int v9fs_mapped_iattr_valid(int iattr_valid)
  *
  */
 
-int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
+int v9fs_vfs_setattr_dotl(struct user_namespace *mnt_userns,
+			  struct dentry *dentry, struct iattr *iattr)
 {
 	int retval, use_dentry = 0;
 	struct p9_fid *fid = NULL;
@@ -549,7 +552,7 @@ int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
 
 	p9_debug(P9_DEBUG_VFS, "\n");
 
-	retval = setattr_prepare(dentry, iattr);
+	retval = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (retval)
 		return retval;
 
@@ -590,7 +593,7 @@ int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
 		truncate_setsize(inode, iattr->ia_size);
 
 	v9fs_invalidate_inode_attr(inode);
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 	mark_inode_dirty(inode);
 	if (iattr->ia_valid & ATTR_MODE) {
 		/* We also want to update ACL when we update mode bits */
@@ -684,8 +687,8 @@ v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode,
 }
 
 static int
-v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
-		const char *symname)
+v9fs_vfs_symlink_dotl(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, const char *symname)
 {
 	int err;
 	kgid_t gid;
@@ -824,8 +827,8 @@ v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
  *
  */
 static int
-v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
-		dev_t rdev)
+v9fs_vfs_mknod_dotl(struct user_namespace *mnt_userns, struct inode *dir,
+		    struct dentry *dentry, umode_t omode, dev_t rdev)
 {
 	int err;
 	kgid_t gid;
diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index 87217dd0433e..ee331845e2c7 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -157,6 +157,7 @@ static int v9fs_xattr_handler_get(const struct xattr_handler *handler,
 }
 
 static int v9fs_xattr_handler_set(const struct xattr_handler *handler,
+				  struct user_namespace *mnt_userns,
 				  struct dentry *dentry, struct inode *inode,
 				  const char *name, const void *value,
 				  size_t size, int flags)
diff --git a/fs/adfs/adfs.h b/fs/adfs/adfs.h
index 699c4fa8b78b..06b7c92343ad 100644
--- a/fs/adfs/adfs.h
+++ b/fs/adfs/adfs.h
@@ -144,7 +144,8 @@ struct adfs_discmap {
 /* Inode stuff */
 struct inode *adfs_iget(struct super_block *sb, struct object_info *obj);
 int adfs_write_inode(struct inode *inode, struct writeback_control *wbc);
-int adfs_notify_change(struct dentry *dentry, struct iattr *attr);
+int adfs_notify_change(struct user_namespace *mnt_userns, struct dentry *dentry,
+		       struct iattr *attr);
 
 /* map.c */
 int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset);
diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c
index 32620f4a7623..fb7ee026d101 100644
--- a/fs/adfs/inode.c
+++ b/fs/adfs/inode.c
@@ -292,14 +292,15 @@ out:
  * later.
  */
 int
-adfs_notify_change(struct dentry *dentry, struct iattr *attr)
+adfs_notify_change(struct user_namespace *mnt_userns, struct dentry *dentry,
+		   struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct super_block *sb = inode->i_sb;
 	unsigned int ia_valid = attr->ia_valid;
 	int error;
 	
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 
 	/*
 	 * we can't change the UID or GID of any file -
diff --git a/fs/affs/affs.h b/fs/affs/affs.h
index a755bef7c4c7..bfa89e131ead 100644
--- a/fs/affs/affs.h
+++ b/fs/affs/affs.h
@@ -167,27 +167,33 @@ extern const struct export_operations affs_export_ops;
 extern int	affs_hash_name(struct super_block *sb, const u8 *name, unsigned int len);
 extern struct dentry *affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int);
 extern int	affs_unlink(struct inode *dir, struct dentry *dentry);
-extern int	affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool);
-extern int	affs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
+extern int	affs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool);
+extern int	affs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode);
 extern int	affs_rmdir(struct inode *dir, struct dentry *dentry);
 extern int	affs_link(struct dentry *olddentry, struct inode *dir,
 			  struct dentry *dentry);
-extern int	affs_symlink(struct inode *dir, struct dentry *dentry,
-			     const char *symname);
-extern int	affs_rename2(struct inode *old_dir, struct dentry *old_dentry,
-			    struct inode *new_dir, struct dentry *new_dentry,
-			    unsigned int flags);
+extern int	affs_symlink(struct user_namespace *mnt_userns,
+			struct inode *dir, struct dentry *dentry,
+			const char *symname);
+extern int	affs_rename2(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry,
+			unsigned int flags);
 
 /* inode.c */
 
 extern struct inode		*affs_new_inode(struct inode *dir);
-extern int			 affs_notify_change(struct dentry *dentry, struct iattr *attr);
+extern int			 affs_notify_change(struct user_namespace *mnt_userns,
+					struct dentry *dentry, struct iattr *attr);
 extern void			 affs_evict_inode(struct inode *inode);
 extern struct inode		*affs_iget(struct super_block *sb,
 					unsigned long ino);
 extern int			 affs_write_inode(struct inode *inode,
 					struct writeback_control *wbc);
-extern int			 affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type);
+extern int			 affs_add_entry(struct inode *dir, struct inode *inode,
+					struct dentry *dentry, s32 type);
 
 /* file.c */
 
diff --git a/fs/affs/inode.c b/fs/affs/inode.c
index 044412110b52..2352a75bd9d6 100644
--- a/fs/affs/inode.c
+++ b/fs/affs/inode.c
@@ -216,14 +216,15 @@ affs_write_inode(struct inode *inode, struct writeback_control *wbc)
 }
 
 int
-affs_notify_change(struct dentry *dentry, struct iattr *attr)
+affs_notify_change(struct user_namespace *mnt_userns, struct dentry *dentry,
+		   struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
 
 	pr_debug("notify_change(%lu,0x%x)\n", inode->i_ino, attr->ia_valid);
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		goto out;
 
@@ -249,7 +250,7 @@ affs_notify_change(struct dentry *dentry, struct iattr *attr)
 		affs_truncate(inode);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 
 	if (attr->ia_valid & ATTR_MODE)
diff --git a/fs/affs/namei.c b/fs/affs/namei.c
index 5400a876d73f..bcab18956b4f 100644
--- a/fs/affs/namei.c
+++ b/fs/affs/namei.c
@@ -242,7 +242,8 @@ affs_unlink(struct inode *dir, struct dentry *dentry)
 }
 
 int
-affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
+affs_create(struct user_namespace *mnt_userns, struct inode *dir,
+	    struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct super_block *sb = dir->i_sb;
 	struct inode	*inode;
@@ -273,7 +274,8 @@ affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
 }
 
 int
-affs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+affs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+	   struct dentry *dentry, umode_t mode)
 {
 	struct inode		*inode;
 	int			 error;
@@ -311,7 +313,8 @@ affs_rmdir(struct inode *dir, struct dentry *dentry)
 }
 
 int
-affs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+affs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+	     struct dentry *dentry, const char *symname)
 {
 	struct super_block	*sb = dir->i_sb;
 	struct buffer_head	*bh;
@@ -500,9 +503,9 @@ done:
 	return retval;
 }
 
-int affs_rename2(struct inode *old_dir, struct dentry *old_dentry,
-			struct inode *new_dir, struct dentry *new_dentry,
-			unsigned int flags)
+int affs_rename2(struct user_namespace *mnt_userns, struct inode *old_dir,
+		 struct dentry *old_dentry, struct inode *new_dir,
+		 struct dentry *new_dentry, unsigned int flags)
 {
 
 	if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index 7bd659ad959e..714fcca9af99 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -28,18 +28,19 @@ static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int
 				  loff_t fpos, u64 ino, unsigned dtype);
 static int afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen,
 			      loff_t fpos, u64 ino, unsigned dtype);
-static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		      bool excl);
-static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
+static int afs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, bool excl);
+static int afs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode);
 static int afs_rmdir(struct inode *dir, struct dentry *dentry);
 static int afs_unlink(struct inode *dir, struct dentry *dentry);
 static int afs_link(struct dentry *from, struct inode *dir,
 		    struct dentry *dentry);
-static int afs_symlink(struct inode *dir, struct dentry *dentry,
-		       const char *content);
-static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		      struct inode *new_dir, struct dentry *new_dentry,
-		      unsigned int flags);
+static int afs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, const char *content);
+static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags);
 static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags);
 static void afs_dir_invalidatepage(struct page *page, unsigned int offset,
 				   unsigned int length);
@@ -1325,7 +1326,8 @@ static const struct afs_operation_ops afs_mkdir_operation = {
 /*
  * create a directory on an AFS filesystem
  */
-static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int afs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode)
 {
 	struct afs_operation *op;
 	struct afs_vnode *dvnode = AFS_FS_I(dir);
@@ -1619,8 +1621,8 @@ static const struct afs_operation_ops afs_create_operation = {
 /*
  * create a regular file on an AFS filesystem
  */
-static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		      bool excl)
+static int afs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct afs_operation *op;
 	struct afs_vnode *dvnode = AFS_FS_I(dir);
@@ -1741,8 +1743,8 @@ static const struct afs_operation_ops afs_symlink_operation = {
 /*
  * create a symlink in an AFS filesystem
  */
-static int afs_symlink(struct inode *dir, struct dentry *dentry,
-		       const char *content)
+static int afs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, const char *content)
 {
 	struct afs_operation *op;
 	struct afs_vnode *dvnode = AFS_FS_I(dir);
@@ -1876,9 +1878,9 @@ static const struct afs_operation_ops afs_rename_operation = {
 /*
  * rename a file in an AFS filesystem and/or move it between directories
  */
-static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		      struct inode *new_dir, struct dentry *new_dentry,
-		      unsigned int flags)
+static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags)
 {
 	struct afs_operation *op;
 	struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index b0d7b892090d..1156b2df28d3 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -734,8 +734,8 @@ error_unlock:
 /*
  * read the attributes of an inode
  */
-int afs_getattr(const struct path *path, struct kstat *stat,
-		u32 request_mask, unsigned int query_flags)
+int afs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		struct kstat *stat, u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct afs_vnode *vnode = AFS_FS_I(inode);
@@ -745,7 +745,7 @@ int afs_getattr(const struct path *path, struct kstat *stat,
 
 	do {
 		read_seqbegin_or_lock(&vnode->cb_lock, &seq);
-		generic_fillattr(inode, stat);
+		generic_fillattr(&init_user_ns, inode, stat);
 		if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
 		    stat->nlink > 0)
 			stat->nlink -= 1;
@@ -857,7 +857,8 @@ static const struct afs_operation_ops afs_setattr_operation = {
 /*
  * set the attributes of an inode
  */
-int afs_setattr(struct dentry *dentry, struct iattr *attr)
+int afs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		struct iattr *attr)
 {
 	struct afs_operation *op;
 	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 0d150a29e39e..b626e38e9ab5 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -1149,8 +1149,9 @@ extern struct inode *afs_iget(struct afs_operation *, struct afs_vnode_param *);
 extern struct inode *afs_root_iget(struct super_block *, struct key *);
 extern bool afs_check_validity(struct afs_vnode *);
 extern int afs_validate(struct afs_vnode *, struct key *);
-extern int afs_getattr(const struct path *, struct kstat *, u32, unsigned int);
-extern int afs_setattr(struct dentry *, struct iattr *);
+extern int afs_getattr(struct user_namespace *mnt_userns, const struct path *,
+		       struct kstat *, u32, unsigned int);
+extern int afs_setattr(struct user_namespace *mnt_userns, struct dentry *, struct iattr *);
 extern void afs_evict_inode(struct inode *);
 extern int afs_drop_inode(struct inode *);
 
@@ -1361,7 +1362,7 @@ extern void afs_zap_permits(struct rcu_head *);
 extern struct key *afs_request_key(struct afs_cell *);
 extern struct key *afs_request_key_rcu(struct afs_cell *);
 extern int afs_check_permit(struct afs_vnode *, struct key *, afs_access_t *);
-extern int afs_permission(struct inode *, int);
+extern int afs_permission(struct user_namespace *, struct inode *, int);
 extern void __exit afs_clean_up_permit_cache(void);
 
 /*
diff --git a/fs/afs/security.c b/fs/afs/security.c
index 9cf3102f370c..3c7a8fc4f93f 100644
--- a/fs/afs/security.c
+++ b/fs/afs/security.c
@@ -396,7 +396,8 @@ int afs_check_permit(struct afs_vnode *vnode, struct key *key,
  * - AFS ACLs are attached to directories only, and a file is controlled by its
  *   parent directory's ACL
  */
-int afs_permission(struct inode *inode, int mask)
+int afs_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		   int mask)
 {
 	struct afs_vnode *vnode = AFS_FS_I(inode);
 	afs_access_t access;
diff --git a/fs/afs/xattr.c b/fs/afs/xattr.c
index 95c573dcda11..c629caae5002 100644
--- a/fs/afs/xattr.c
+++ b/fs/afs/xattr.c
@@ -120,6 +120,7 @@ static const struct afs_operation_ops afs_store_acl_operation = {
  * Set a file's AFS3 ACL.
  */
 static int afs_xattr_set_acl(const struct xattr_handler *handler,
+			     struct user_namespace *mnt_userns,
                              struct dentry *dentry,
                              struct inode *inode, const char *name,
                              const void *buffer, size_t size, int flags)
@@ -248,6 +249,7 @@ static const struct afs_operation_ops yfs_store_opaque_acl2_operation = {
  * Set a file's YFS ACL.
  */
 static int afs_xattr_set_yfs(const struct xattr_handler *handler,
+			     struct user_namespace *mnt_userns,
                              struct dentry *dentry,
                              struct inode *inode, const char *name,
                              const void *buffer, size_t size, int flags)
diff --git a/fs/attr.c b/fs/attr.c
index b4bbdbd4c8ca..87ef39db1c34 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -18,27 +18,55 @@
 #include <linux/evm.h>
 #include <linux/ima.h>
 
-static bool chown_ok(const struct inode *inode, kuid_t uid)
+/**
+ * chown_ok - verify permissions to chown inode
+ * @mnt_userns:	user namespace of the mount @inode was found from
+ * @inode:	inode to check permissions on
+ * @uid:	uid to chown @inode to
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ */
+static bool chown_ok(struct user_namespace *mnt_userns,
+		     const struct inode *inode,
+		     kuid_t uid)
 {
-	if (uid_eq(current_fsuid(), inode->i_uid) &&
-	    uid_eq(uid, inode->i_uid))
+	kuid_t kuid = i_uid_into_mnt(mnt_userns, inode);
+	if (uid_eq(current_fsuid(), kuid) && uid_eq(uid, kuid))
 		return true;
-	if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
+	if (capable_wrt_inode_uidgid(mnt_userns, inode, CAP_CHOWN))
 		return true;
-	if (uid_eq(inode->i_uid, INVALID_UID) &&
+	if (uid_eq(kuid, INVALID_UID) &&
 	    ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
 		return true;
 	return false;
 }
 
-static bool chgrp_ok(const struct inode *inode, kgid_t gid)
+/**
+ * chgrp_ok - verify permissions to chgrp inode
+ * @mnt_userns:	user namespace of the mount @inode was found from
+ * @inode:	inode to check permissions on
+ * @gid:	gid to chown @inode to
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ */
+static bool chgrp_ok(struct user_namespace *mnt_userns,
+		     const struct inode *inode, kgid_t gid)
 {
-	if (uid_eq(current_fsuid(), inode->i_uid) &&
-	    (in_group_p(gid) || gid_eq(gid, inode->i_gid)))
+	kgid_t kgid = i_gid_into_mnt(mnt_userns, inode);
+	if (uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode)) &&
+	    (in_group_p(gid) || gid_eq(gid, kgid)))
 		return true;
-	if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
+	if (capable_wrt_inode_uidgid(mnt_userns, inode, CAP_CHOWN))
 		return true;
-	if (gid_eq(inode->i_gid, INVALID_GID) &&
+	if (gid_eq(kgid, INVALID_GID) &&
 	    ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
 		return true;
 	return false;
@@ -46,6 +74,7 @@ static bool chgrp_ok(const struct inode *inode, kgid_t gid)
 
 /**
  * setattr_prepare - check if attribute changes to a dentry are allowed
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @dentry:	dentry to check
  * @attr:	attributes to change
  *
@@ -55,10 +84,17 @@ static bool chgrp_ok(const struct inode *inode, kgid_t gid)
  * SGID bit from mode if user is not allowed to set it. Also file capabilities
  * and IMA extended attributes are cleared if ATTR_KILL_PRIV is set.
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ *
  * Should be called as the first thing in ->setattr implementations,
  * possibly after taking additional locks.
  */
-int setattr_prepare(struct dentry *dentry, struct iattr *attr)
+int setattr_prepare(struct user_namespace *mnt_userns, struct dentry *dentry,
+		    struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	unsigned int ia_valid = attr->ia_valid;
@@ -78,27 +114,27 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr)
 		goto kill_priv;
 
 	/* Make sure a caller can chown. */
-	if ((ia_valid & ATTR_UID) && !chown_ok(inode, attr->ia_uid))
+	if ((ia_valid & ATTR_UID) && !chown_ok(mnt_userns, inode, attr->ia_uid))
 		return -EPERM;
 
 	/* Make sure caller can chgrp. */
-	if ((ia_valid & ATTR_GID) && !chgrp_ok(inode, attr->ia_gid))
+	if ((ia_valid & ATTR_GID) && !chgrp_ok(mnt_userns, inode, attr->ia_gid))
 		return -EPERM;
 
 	/* Make sure a caller can chmod. */
 	if (ia_valid & ATTR_MODE) {
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EPERM;
 		/* Also check the setgid bit! */
-		if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
-				inode->i_gid) &&
-		    !capable_wrt_inode_uidgid(inode, CAP_FSETID))
+               if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
+                                i_gid_into_mnt(mnt_userns, inode)) &&
+                    !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID))
 			attr->ia_mode &= ~S_ISGID;
 	}
 
 	/* Check for setting the inode time. */
 	if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) {
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EPERM;
 	}
 
@@ -107,7 +143,7 @@ kill_priv:
 	if (ia_valid & ATTR_KILL_PRIV) {
 		int error;
 
-		error = security_inode_killpriv(dentry);
+		error = security_inode_killpriv(mnt_userns, dentry);
 		if (error)
 			return error;
 	}
@@ -162,20 +198,33 @@ EXPORT_SYMBOL(inode_newsize_ok);
 
 /**
  * setattr_copy - copy simple metadata updates into the generic inode
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode:	the inode to be updated
  * @attr:	the new attributes
  *
  * setattr_copy must be called with i_mutex held.
  *
  * setattr_copy updates the inode's metadata with that specified
- * in attr. Noticeably missing is inode size update, which is more complex
+ * in attr on idmapped mounts. If file ownership is changed setattr_copy
+ * doesn't map ia_uid and ia_gid. It will asssume the caller has already
+ * provided the intended values. Necessary permission checks to determine
+ * whether or not the S_ISGID property needs to be removed are performed with
+ * the correct idmapped mount permission helpers.
+ * Noticeably missing is inode size update, which is more complex
  * as it requires pagecache updates.
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ *
  * The inode is not marked as dirty after this operation. The rationale is
  * that for "simple" filesystems, the struct inode is the inode storage.
  * The caller is free to mark the inode dirty afterwards if needed.
  */
-void setattr_copy(struct inode *inode, const struct iattr *attr)
+void setattr_copy(struct user_namespace *mnt_userns, struct inode *inode,
+		  const struct iattr *attr)
 {
 	unsigned int ia_valid = attr->ia_valid;
 
@@ -191,9 +240,9 @@ void setattr_copy(struct inode *inode, const struct iattr *attr)
 		inode->i_ctime = attr->ia_ctime;
 	if (ia_valid & ATTR_MODE) {
 		umode_t mode = attr->ia_mode;
-
-		if (!in_group_p(inode->i_gid) &&
-		    !capable_wrt_inode_uidgid(inode, CAP_FSETID))
+		kgid_t kgid = i_gid_into_mnt(mnt_userns, inode);
+		if (!in_group_p(kgid) &&
+		    !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID))
 			mode &= ~S_ISGID;
 		inode->i_mode = mode;
 	}
@@ -202,6 +251,7 @@ EXPORT_SYMBOL(setattr_copy);
 
 /**
  * notify_change - modify attributes of a filesytem object
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @dentry:	object affected
  * @attr:	new attributes
  * @delegated_inode: returns inode, if the inode is delegated
@@ -214,13 +264,23 @@ EXPORT_SYMBOL(setattr_copy);
  * retry.  Because breaking a delegation may take a long time, the
  * caller should drop the i_mutex before doing so.
  *
+ * If file ownership is changed notify_change() doesn't map ia_uid and
+ * ia_gid. It will asssume the caller has already provided the intended values.
+ *
  * Alternatively, a caller may pass NULL for delegated_inode.  This may
  * be appropriate for callers that expect the underlying filesystem not
  * to be NFS exported.  Also, passing NULL is fine for callers holding
  * the file open for write, as there can be no conflicting delegation in
  * that case.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
  */
-int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
+int notify_change(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *attr, struct inode **delegated_inode)
 {
 	struct inode *inode = dentry->d_inode;
 	umode_t mode = inode->i_mode;
@@ -243,8 +303,8 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
 		if (IS_IMMUTABLE(inode))
 			return -EPERM;
 
-		if (!inode_owner_or_capable(inode)) {
-			error = inode_permission(inode, MAY_WRITE);
+		if (!inode_owner_or_capable(mnt_userns, inode)) {
+			error = inode_permission(mnt_userns, inode, MAY_WRITE);
 			if (error)
 				return error;
 		}
@@ -320,9 +380,11 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
 	/* Don't allow modifications of files with invalid uids or
 	 * gids unless those uids & gids are being made valid.
 	 */
-	if (!(ia_valid & ATTR_UID) && !uid_valid(inode->i_uid))
+	if (!(ia_valid & ATTR_UID) &&
+	    !uid_valid(i_uid_into_mnt(mnt_userns, inode)))
 		return -EOVERFLOW;
-	if (!(ia_valid & ATTR_GID) && !gid_valid(inode->i_gid))
+	if (!(ia_valid & ATTR_GID) &&
+	    !gid_valid(i_gid_into_mnt(mnt_userns, inode)))
 		return -EOVERFLOW;
 
 	error = security_inode_setattr(dentry, attr);
@@ -333,13 +395,13 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
 		return error;
 
 	if (inode->i_op->setattr)
-		error = inode->i_op->setattr(dentry, attr);
+		error = inode->i_op->setattr(mnt_userns, dentry, attr);
 	else
-		error = simple_setattr(dentry, attr);
+		error = simple_setattr(mnt_userns, dentry, attr);
 
 	if (!error) {
 		fsnotify_change(dentry, ia_valid);
-		ima_inode_post_setattr(dentry);
+		ima_inode_post_setattr(mnt_userns, dentry);
 		evm_inode_post_setattr(dentry, ia_valid);
 	}
 
diff --git a/fs/autofs/root.c b/fs/autofs/root.c
index 5aaa1732bf1e..91fe4548c256 100644
--- a/fs/autofs/root.c
+++ b/fs/autofs/root.c
@@ -10,10 +10,12 @@
 
 #include "autofs_i.h"
 
-static int autofs_dir_symlink(struct inode *, struct dentry *, const char *);
+static int autofs_dir_symlink(struct user_namespace *, struct inode *,
+			      struct dentry *, const char *);
 static int autofs_dir_unlink(struct inode *, struct dentry *);
 static int autofs_dir_rmdir(struct inode *, struct dentry *);
-static int autofs_dir_mkdir(struct inode *, struct dentry *, umode_t);
+static int autofs_dir_mkdir(struct user_namespace *, struct inode *,
+			    struct dentry *, umode_t);
 static long autofs_root_ioctl(struct file *, unsigned int, unsigned long);
 #ifdef CONFIG_COMPAT
 static long autofs_root_compat_ioctl(struct file *,
@@ -524,9 +526,9 @@ static struct dentry *autofs_lookup(struct inode *dir,
 	return NULL;
 }
 
-static int autofs_dir_symlink(struct inode *dir,
-			       struct dentry *dentry,
-			       const char *symname)
+static int autofs_dir_symlink(struct user_namespace *mnt_userns,
+			      struct inode *dir, struct dentry *dentry,
+			      const char *symname)
 {
 	struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
 	struct autofs_info *ino = autofs_dentry_ino(dentry);
@@ -715,8 +717,9 @@ static int autofs_dir_rmdir(struct inode *dir, struct dentry *dentry)
 	return 0;
 }
 
-static int autofs_dir_mkdir(struct inode *dir,
-			    struct dentry *dentry, umode_t mode)
+static int autofs_dir_mkdir(struct user_namespace *mnt_userns,
+			    struct inode *dir, struct dentry *dentry,
+			    umode_t mode)
 {
 	struct autofs_sb_info *sbi = autofs_sbi(dir->i_sb);
 	struct autofs_info *ino = autofs_dentry_ino(dentry);
diff --git a/fs/bad_inode.c b/fs/bad_inode.c
index 54f0ce444272..48e16144c1f7 100644
--- a/fs/bad_inode.c
+++ b/fs/bad_inode.c
@@ -27,8 +27,9 @@ static const struct file_operations bad_file_ops =
 	.open		= bad_file_open,
 };
 
-static int bad_inode_create (struct inode *dir, struct dentry *dentry,
-		umode_t mode, bool excl)
+static int bad_inode_create(struct user_namespace *mnt_userns,
+			    struct inode *dir, struct dentry *dentry,
+			    umode_t mode, bool excl)
 {
 	return -EIO;
 }
@@ -50,14 +51,15 @@ static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
 	return -EIO;
 }
 
-static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
-		const char *symname)
+static int bad_inode_symlink(struct user_namespace *mnt_userns,
+			     struct inode *dir, struct dentry *dentry,
+			     const char *symname)
 {
 	return -EIO;
 }
 
-static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
-			umode_t mode)
+static int bad_inode_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			   struct dentry *dentry, umode_t mode)
 {
 	return -EIO;
 }
@@ -67,13 +69,14 @@ static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
 	return -EIO;
 }
 
-static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
-			umode_t mode, dev_t rdev)
+static int bad_inode_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+			   struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	return -EIO;
 }
 
-static int bad_inode_rename2(struct inode *old_dir, struct dentry *old_dentry,
+static int bad_inode_rename2(struct user_namespace *mnt_userns,
+			     struct inode *old_dir, struct dentry *old_dentry,
 			     struct inode *new_dir, struct dentry *new_dentry,
 			     unsigned int flags)
 {
@@ -86,18 +89,21 @@ static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
 	return -EIO;
 }
 
-static int bad_inode_permission(struct inode *inode, int mask)
+static int bad_inode_permission(struct user_namespace *mnt_userns,
+				struct inode *inode, int mask)
 {
 	return -EIO;
 }
 
-static int bad_inode_getattr(const struct path *path, struct kstat *stat,
+static int bad_inode_getattr(struct user_namespace *mnt_userns,
+			     const struct path *path, struct kstat *stat,
 			     u32 request_mask, unsigned int query_flags)
 {
 	return -EIO;
 }
 
-static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
+static int bad_inode_setattr(struct user_namespace *mnt_userns,
+			     struct dentry *direntry, struct iattr *attrs)
 {
 	return -EIO;
 }
@@ -140,13 +146,15 @@ static int bad_inode_atomic_open(struct inode *inode, struct dentry *dentry,
 	return -EIO;
 }
 
-static int bad_inode_tmpfile(struct inode *inode, struct dentry *dentry,
+static int bad_inode_tmpfile(struct user_namespace *mnt_userns,
+			     struct inode *inode, struct dentry *dentry,
 			     umode_t mode)
 {
 	return -EIO;
 }
 
-static int bad_inode_set_acl(struct inode *inode, struct posix_acl *acl,
+static int bad_inode_set_acl(struct user_namespace *mnt_userns,
+			     struct inode *inode, struct posix_acl *acl,
 			     int type)
 {
 	return -EIO;
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c
index d8dfe3a0cb39..34d4f68f786b 100644
--- a/fs/bfs/dir.c
+++ b/fs/bfs/dir.c
@@ -75,8 +75,8 @@ const struct file_operations bfs_dir_operations = {
 	.llseek		= generic_file_llseek,
 };
 
-static int bfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-						bool excl)
+static int bfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, bool excl)
 {
 	int err;
 	struct inode *inode;
@@ -96,7 +96,7 @@ static int bfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	}
 	set_bit(ino, info->si_imap);
 	info->si_freei--;
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 	inode->i_blocks = 0;
 	inode->i_op = &bfs_file_inops;
@@ -199,9 +199,9 @@ out_brelse:
 	return error;
 }
 
-static int bfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		      struct inode *new_dir, struct dentry *new_dentry,
-		      unsigned int flags)
+static int bfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags)
 {
 	struct inode *old_inode, *new_inode;
 	struct buffer_head *old_bh, *new_bh;
diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index a0af1b952c4d..d95eb5c8cb37 100644
--- a/fs/btrfs/acl.c
+++ b/fs/btrfs/acl.c
@@ -107,13 +107,15 @@ out:
 	return ret;
 }
 
-int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int btrfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		  struct posix_acl *acl, int type)
 {
 	int ret;
 	umode_t old_mode = inode->i_mode;
 
 	if (type == ACL_TYPE_ACCESS && acl) {
-		ret = posix_acl_update_mode(inode, &inode->i_mode, &acl);
+		ret = posix_acl_update_mode(&init_user_ns, inode,
+					    &inode->i_mode, &acl);
 		if (ret)
 			return ret;
 	}
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 3bc00aed13b2..bd659354d043 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3635,7 +3635,8 @@ static inline int __btrfs_fs_compat_ro(struct btrfs_fs_info *fs_info, u64 flag)
 /* acl.c */
 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
 struct posix_acl *btrfs_get_acl(struct inode *inode, int type);
-int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+int btrfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		  struct posix_acl *acl, int type);
 int btrfs_init_acl(struct btrfs_trans_handle *trans,
 		   struct inode *inode, struct inode *dir);
 #else
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 535abf898225..2e1c282c202d 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -5212,7 +5212,8 @@ static int btrfs_setsize(struct inode *inode, struct iattr *attr)
 	return ret;
 }
 
-static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
+static int btrfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+			 struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -5221,7 +5222,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
 	if (btrfs_root_readonly(root))
 		return -EROFS;
 
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err)
 		return err;
 
@@ -5232,12 +5233,13 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
 	}
 
 	if (attr->ia_valid) {
-		setattr_copy(inode, attr);
+		setattr_copy(&init_user_ns, inode, attr);
 		inode_inc_iversion(inode);
 		err = btrfs_dirty_inode(inode);
 
 		if (!err && attr->ia_valid & ATTR_MODE)
-			err = posix_acl_chmod(inode, inode->i_mode);
+			err = posix_acl_chmod(&init_user_ns, inode,
+					      inode->i_mode);
 	}
 
 	return err;
@@ -6357,7 +6359,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
 	if (ret != 0)
 		goto fail_unlock;
 
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode_set_bytes(inode, 0);
 
 	inode->i_mtime = current_time(inode);
@@ -6518,8 +6520,8 @@ static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
 	return err;
 }
 
-static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
-			umode_t mode, dev_t rdev)
+static int btrfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 	struct btrfs_trans_handle *trans;
@@ -6582,8 +6584,8 @@ out_unlock:
 	return err;
 }
 
-static int btrfs_create(struct inode *dir, struct dentry *dentry,
-			umode_t mode, bool excl)
+static int btrfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 	struct btrfs_trans_handle *trans;
@@ -6727,7 +6729,8 @@ fail:
 	return err;
 }
 
-static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int btrfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 	struct inode *inode = NULL;
@@ -9017,7 +9020,8 @@ fail:
 	return -ENOMEM;
 }
 
-static int btrfs_getattr(const struct path *path, struct kstat *stat,
+static int btrfs_getattr(struct user_namespace *mnt_userns,
+			 const struct path *path, struct kstat *stat,
 			 u32 request_mask, unsigned int flags)
 {
 	u64 delalloc_bytes;
@@ -9043,7 +9047,7 @@ static int btrfs_getattr(const struct path *path, struct kstat *stat,
 				  STATX_ATTR_IMMUTABLE |
 				  STATX_ATTR_NODUMP);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	stat->dev = BTRFS_I(inode)->root->anon_dev;
 
 	spin_lock(&BTRFS_I(inode)->lock);
@@ -9534,9 +9538,9 @@ out_notrans:
 	return ret;
 }
 
-static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
-			 struct inode *new_dir, struct dentry *new_dentry,
-			 unsigned int flags)
+static int btrfs_rename2(struct user_namespace *mnt_userns, struct inode *old_dir,
+			 struct dentry *old_dentry, struct inode *new_dir,
+			 struct dentry *new_dentry, unsigned int flags)
 {
 	if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
 		return -EINVAL;
@@ -9744,8 +9748,8 @@ out:
 	return ret;
 }
 
-static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
-			 const char *symname)
+static int btrfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, const char *symname)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 	struct btrfs_trans_handle *trans;
@@ -10079,7 +10083,8 @@ static int btrfs_set_page_dirty(struct page *page)
 	return __set_page_dirty_nobuffers(page);
 }
 
-static int btrfs_permission(struct inode *inode, int mask)
+static int btrfs_permission(struct user_namespace *mnt_userns,
+			    struct inode *inode, int mask)
 {
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	umode_t mode = inode->i_mode;
@@ -10091,10 +10096,11 @@ static int btrfs_permission(struct inode *inode, int mask)
 		if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
 			return -EACCES;
 	}
-	return generic_permission(inode, mask);
+	return generic_permission(&init_user_ns, inode, mask);
 }
 
-static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int btrfs_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, umode_t mode)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 	struct btrfs_trans_handle *trans;
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a8c60d46d19c..072e77726e94 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -213,7 +213,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 	const char *comp = NULL;
 	u32 binode_flags;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EPERM;
 
 	if (btrfs_root_readonly(root))
@@ -429,7 +429,7 @@ static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
 	unsigned old_i_flags;
 	int ret = 0;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EPERM;
 
 	if (btrfs_root_readonly(root))
@@ -925,13 +925,14 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
 	BUG_ON(d_inode(victim->d_parent) != dir);
 	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 
-	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 	if (IS_APPEND(dir))
 		return -EPERM;
-	if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
-	    IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
+	if (check_sticky(&init_user_ns, dir, d_inode(victim)) ||
+	    IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||
+	    IS_SWAPFILE(d_inode(victim)))
 		return -EPERM;
 	if (isdir) {
 		if (!d_is_dir(victim))
@@ -954,7 +955,7 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 		return -EEXIST;
 	if (IS_DEADDIR(dir))
 		return -ENOENT;
-	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
 }
 
 /*
@@ -1871,7 +1872,7 @@ static noinline int __btrfs_ioctl_snap_create(struct file *file,
 			btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
 				   "Snapshot src from another FS");
 			ret = -EXDEV;
-		} else if (!inode_owner_or_capable(src_inode)) {
+		} else if (!inode_owner_or_capable(&init_user_ns, src_inode)) {
 			/*
 			 * Subvolume creation is not restricted, but snapshots
 			 * are limited to own subvolumes only
@@ -1991,7 +1992,7 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
 	u64 flags;
 	int ret = 0;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EPERM;
 
 	ret = mnt_want_write_file(file);
@@ -2547,7 +2548,8 @@ static int btrfs_search_path_in_tree_user(struct inode *inode,
 				ret = PTR_ERR(temp_inode);
 				goto out_put;
 			}
-			ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
+			ret = inode_permission(&init_user_ns, temp_inode,
+					       MAY_READ | MAY_EXEC);
 			iput(temp_inode);
 			if (ret) {
 				ret = -EACCES;
@@ -3077,7 +3079,8 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
 		if (root == dest)
 			goto out_dput;
 
-		err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
+		err = inode_permission(&init_user_ns, inode,
+				       MAY_WRITE | MAY_EXEC);
 		if (err)
 			goto out_dput;
 	}
@@ -3148,7 +3151,7 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
 		 * running and allows defrag on files open in read-only mode.
 		 */
 		if (!capable(CAP_SYS_ADMIN) &&
-		    inode_permission(inode, MAY_WRITE)) {
+		    inode_permission(&init_user_ns, inode, MAY_WRITE)) {
 			ret = -EPERM;
 			goto out;
 		}
@@ -4460,7 +4463,7 @@ static long _btrfs_ioctl_set_received_subvol(struct file *file,
 	int ret = 0;
 	int received_uuid_changed;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EPERM;
 
 	ret = mnt_want_write_file(file);
diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c
index 6bd97bd4cb37..3a4099a2bf05 100644
--- a/fs/btrfs/tests/btrfs-tests.c
+++ b/fs/btrfs/tests/btrfs-tests.c
@@ -62,7 +62,7 @@ struct inode *btrfs_new_test_inode(void)
 	BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
 	BTRFS_I(inode)->location.objectid = BTRFS_FIRST_FREE_OBJECTID;
 	BTRFS_I(inode)->location.offset = 0;
-	inode_init_owner(inode, NULL, S_IFREG);
+	inode_init_owner(&init_user_ns, inode, NULL, S_IFREG);
 
 	return inode;
 }
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index af6246f36a9e..b025102e435f 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -362,6 +362,7 @@ static int btrfs_xattr_handler_get(const struct xattr_handler *handler,
 }
 
 static int btrfs_xattr_handler_set(const struct xattr_handler *handler,
+				   struct user_namespace *mnt_userns,
 				   struct dentry *unused, struct inode *inode,
 				   const char *name, const void *buffer,
 				   size_t size, int flags)
@@ -371,6 +372,7 @@ static int btrfs_xattr_handler_set(const struct xattr_handler *handler,
 }
 
 static int btrfs_xattr_handler_set_prop(const struct xattr_handler *handler,
+					struct user_namespace *mnt_userns,
 					struct dentry *unused, struct inode *inode,
 					const char *name, const void *value,
 					size_t size, int flags)
diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c
index 4cea5fbf695e..5efa6a3702c0 100644
--- a/fs/cachefiles/interface.c
+++ b/fs/cachefiles/interface.c
@@ -470,14 +470,14 @@ static int cachefiles_attr_changed(struct fscache_object *_object)
 		_debug("discard tail %llx", oi_size);
 		newattrs.ia_valid = ATTR_SIZE;
 		newattrs.ia_size = oi_size & PAGE_MASK;
-		ret = notify_change(object->backer, &newattrs, NULL);
+		ret = notify_change(&init_user_ns, object->backer, &newattrs, NULL);
 		if (ret < 0)
 			goto truncate_failed;
 	}
 
 	newattrs.ia_valid = ATTR_SIZE;
 	newattrs.ia_size = ni_size;
-	ret = notify_change(object->backer, &newattrs, NULL);
+	ret = notify_change(&init_user_ns, object->backer, &newattrs, NULL);
 
 truncate_failed:
 	inode_unlock(d_inode(object->backer));
diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index ecc8ecbbfa5a..7bf0732ae25c 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -311,7 +311,8 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache,
 			cachefiles_io_error(cache, "Unlink security error");
 		} else {
 			trace_cachefiles_unlink(object, rep, why);
-			ret = vfs_unlink(d_inode(dir), rep, NULL);
+			ret = vfs_unlink(&init_user_ns, d_inode(dir), rep,
+					 NULL);
 
 			if (preemptive)
 				cachefiles_mark_object_buried(cache, rep, why);
@@ -412,9 +413,16 @@ try_again:
 	if (ret < 0) {
 		cachefiles_io_error(cache, "Rename security error %d", ret);
 	} else {
+		struct renamedata rd = {
+			.old_mnt_userns	= &init_user_ns,
+			.old_dir	= d_inode(dir),
+			.old_dentry	= rep,
+			.new_mnt_userns	= &init_user_ns,
+			.new_dir	= d_inode(cache->graveyard),
+			.new_dentry	= grave,
+		};
 		trace_cachefiles_rename(object, rep, grave, why);
-		ret = vfs_rename(d_inode(dir), rep,
-				 d_inode(cache->graveyard), grave, NULL, 0);
+		ret = vfs_rename(&rd);
 		if (ret != 0 && ret != -ENOMEM)
 			cachefiles_io_error(cache,
 					    "Rename failed with error %d", ret);
@@ -561,7 +569,7 @@ lookup_again:
 			if (ret < 0)
 				goto create_error;
 			start = jiffies;
-			ret = vfs_mkdir(d_inode(dir), next, 0);
+			ret = vfs_mkdir(&init_user_ns, d_inode(dir), next, 0);
 			cachefiles_hist(cachefiles_mkdir_histogram, start);
 			if (!key)
 				trace_cachefiles_mkdir(object, next, ret);
@@ -597,7 +605,8 @@ lookup_again:
 			if (ret < 0)
 				goto create_error;
 			start = jiffies;
-			ret = vfs_create(d_inode(dir), next, S_IFREG, true);
+			ret = vfs_create(&init_user_ns, d_inode(dir), next,
+					 S_IFREG, true);
 			cachefiles_hist(cachefiles_create_histogram, start);
 			trace_cachefiles_create(object, next, ret);
 			if (ret < 0)
@@ -791,7 +800,7 @@ retry:
 		ret = security_path_mkdir(&path, subdir, 0700);
 		if (ret < 0)
 			goto mkdir_error;
-		ret = vfs_mkdir(d_inode(dir), subdir, 0700);
+		ret = vfs_mkdir(&init_user_ns, d_inode(dir), subdir, 0700);
 		if (ret < 0)
 			goto mkdir_error;
 
diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c
index 72e42438f3d7..a591b5e09637 100644
--- a/fs/cachefiles/xattr.c
+++ b/fs/cachefiles/xattr.c
@@ -39,8 +39,8 @@ int cachefiles_check_object_type(struct cachefiles_object *object)
 	_enter("%p{%s}", object, type);
 
 	/* attempt to install a type label directly */
-	ret = vfs_setxattr(dentry, cachefiles_xattr_cache, type, 2,
-			   XATTR_CREATE);
+	ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, type,
+			   2, XATTR_CREATE);
 	if (ret == 0) {
 		_debug("SET"); /* we succeeded */
 		goto error;
@@ -54,7 +54,8 @@ int cachefiles_check_object_type(struct cachefiles_object *object)
 	}
 
 	/* read the current type label */
-	ret = vfs_getxattr(dentry, cachefiles_xattr_cache, xtype, 3);
+	ret = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, xtype,
+			   3);
 	if (ret < 0) {
 		if (ret == -ERANGE)
 			goto bad_type_length;
@@ -110,9 +111,8 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object,
 	_debug("SET #%u", auxdata->len);
 
 	clear_bit(FSCACHE_COOKIE_AUX_UPDATED, &object->fscache.cookie->flags);
-	ret = vfs_setxattr(dentry, cachefiles_xattr_cache,
-			   &auxdata->type, auxdata->len,
-			   XATTR_CREATE);
+	ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
+			   &auxdata->type, auxdata->len, XATTR_CREATE);
 	if (ret < 0 && ret != -ENOMEM)
 		cachefiles_io_error_obj(
 			object,
@@ -140,9 +140,8 @@ int cachefiles_update_object_xattr(struct cachefiles_object *object,
 	_debug("SET #%u", auxdata->len);
 
 	clear_bit(FSCACHE_COOKIE_AUX_UPDATED, &object->fscache.cookie->flags);
-	ret = vfs_setxattr(dentry, cachefiles_xattr_cache,
-			   &auxdata->type, auxdata->len,
-			   XATTR_REPLACE);
+	ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
+			   &auxdata->type, auxdata->len, XATTR_REPLACE);
 	if (ret < 0 && ret != -ENOMEM)
 		cachefiles_io_error_obj(
 			object,
@@ -171,7 +170,7 @@ int cachefiles_check_auxdata(struct cachefiles_object *object)
 	if (!auxbuf)
 		return -ENOMEM;
 
-	xlen = vfs_getxattr(dentry, cachefiles_xattr_cache,
+	xlen = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
 			    &auxbuf->type, 512 + 1);
 	ret = -ESTALE;
 	if (xlen < 1 ||
@@ -213,7 +212,7 @@ int cachefiles_check_object_xattr(struct cachefiles_object *object,
 	}
 
 	/* read the current type label */
-	ret = vfs_getxattr(dentry, cachefiles_xattr_cache,
+	ret = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
 			   &auxbuf->type, 512 + 1);
 	if (ret < 0) {
 		if (ret == -ENODATA)
@@ -270,9 +269,9 @@ int cachefiles_check_object_xattr(struct cachefiles_object *object,
 		}
 
 		/* update the current label */
-		ret = vfs_setxattr(dentry, cachefiles_xattr_cache,
-				   &auxdata->type, auxdata->len,
-				   XATTR_REPLACE);
+		ret = vfs_setxattr(&init_user_ns, dentry,
+				   cachefiles_xattr_cache, &auxdata->type,
+				   auxdata->len, XATTR_REPLACE);
 		if (ret < 0) {
 			cachefiles_io_error_obj(object,
 						"Can't update xattr on %lu"
@@ -309,7 +308,7 @@ int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
 {
 	int ret;
 
-	ret = vfs_removexattr(dentry, cachefiles_xattr_cache);
+	ret = vfs_removexattr(&init_user_ns, dentry, cachefiles_xattr_cache);
 	if (ret < 0) {
 		if (ret == -ENOENT || ret == -ENODATA)
 			ret = 0;
diff --git a/fs/ceph/acl.c b/fs/ceph/acl.c
index e0465741c591..529af59d9fd3 100644
--- a/fs/ceph/acl.c
+++ b/fs/ceph/acl.c
@@ -82,7 +82,8 @@ retry:
 	return acl;
 }
 
-int ceph_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int ceph_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type)
 {
 	int ret = 0, size = 0;
 	const char *name = NULL;
@@ -100,7 +101,8 @@ int ceph_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 	case ACL_TYPE_ACCESS:
 		name = XATTR_NAME_POSIX_ACL_ACCESS;
 		if (acl) {
-			ret = posix_acl_update_mode(inode, &new_mode, &acl);
+			ret = posix_acl_update_mode(&init_user_ns, inode,
+						    &new_mode, &acl);
 			if (ret)
 				goto out;
 		}
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 858ee7362ff5..83d9358854fb 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -823,8 +823,8 @@ int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
 	return PTR_ERR(result);
 }
 
-static int ceph_mknod(struct inode *dir, struct dentry *dentry,
-		      umode_t mode, dev_t rdev)
+static int ceph_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 	struct ceph_mds_request *req;
@@ -878,14 +878,14 @@ out:
 	return err;
 }
 
-static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		       bool excl)
+static int ceph_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
-	return ceph_mknod(dir, dentry, mode, 0);
+	return ceph_mknod(mnt_userns, dir, dentry, mode, 0);
 }
 
-static int ceph_symlink(struct inode *dir, struct dentry *dentry,
-			    const char *dest)
+static int ceph_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, const char *dest)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 	struct ceph_mds_request *req;
@@ -937,7 +937,8 @@ out:
 	return err;
 }
 
-static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ceph_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 	struct ceph_mds_request *req;
@@ -1183,9 +1184,9 @@ out:
 	return err;
 }
 
-static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
-		       struct inode *new_dir, struct dentry *new_dentry,
-		       unsigned int flags)
+static int ceph_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old_dir->i_sb);
 	struct ceph_mds_request *req;
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 5d20a620e96c..156f849f5385 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2201,7 +2201,8 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr)
 /*
  * setattr
  */
-int ceph_setattr(struct dentry *dentry, struct iattr *attr)
+int ceph_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
@@ -2210,7 +2211,7 @@ int ceph_setattr(struct dentry *dentry, struct iattr *attr)
 	if (ceph_snap(inode) != CEPH_NOSNAP)
 		return -EROFS;
 
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err != 0)
 		return err;
 
@@ -2225,7 +2226,7 @@ int ceph_setattr(struct dentry *dentry, struct iattr *attr)
 	err = __ceph_setattr(inode, attr);
 
 	if (err >= 0 && (attr->ia_valid & ATTR_MODE))
-		err = posix_acl_chmod(inode, attr->ia_mode);
+		err = posix_acl_chmod(&init_user_ns, inode, attr->ia_mode);
 
 	return err;
 }
@@ -2284,7 +2285,8 @@ int __ceph_do_getattr(struct inode *inode, struct page *locked_page,
  * Check inode permissions.  We verify we have a valid value for
  * the AUTH cap, then call the generic handler.
  */
-int ceph_permission(struct inode *inode, int mask)
+int ceph_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		    int mask)
 {
 	int err;
 
@@ -2294,7 +2296,7 @@ int ceph_permission(struct inode *inode, int mask)
 	err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED, false);
 
 	if (!err)
-		err = generic_permission(inode, mask);
+		err = generic_permission(&init_user_ns, inode, mask);
 	return err;
 }
 
@@ -2331,8 +2333,8 @@ static int statx_to_caps(u32 want, umode_t mode)
  * Get all the attributes. If we have sufficient caps for the requested attrs,
  * then we can avoid talking to the MDS at all.
  */
-int ceph_getattr(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int flags)
+int ceph_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct ceph_inode_info *ci = ceph_inode(inode);
@@ -2348,7 +2350,7 @@ int ceph_getattr(const struct path *path, struct kstat *stat,
 			return err;
 	}
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	stat->ino = ceph_present_inode(inode);
 
 	/*
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 13b02887b085..c48bb30c8d70 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1000,10 +1000,13 @@ static inline int ceph_do_getattr(struct inode *inode, int mask, bool force)
 {
 	return __ceph_do_getattr(inode, NULL, mask, force);
 }
-extern int ceph_permission(struct inode *inode, int mask);
+extern int ceph_permission(struct user_namespace *mnt_userns,
+			   struct inode *inode, int mask);
 extern int __ceph_setattr(struct inode *inode, struct iattr *attr);
-extern int ceph_setattr(struct dentry *dentry, struct iattr *attr);
-extern int ceph_getattr(const struct path *path, struct kstat *stat,
+extern int ceph_setattr(struct user_namespace *mnt_userns,
+			struct dentry *dentry, struct iattr *attr);
+extern int ceph_getattr(struct user_namespace *mnt_userns,
+			const struct path *path, struct kstat *stat,
 			u32 request_mask, unsigned int flags);
 
 /* xattr.c */
@@ -1064,7 +1067,8 @@ void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx);
 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 
 struct posix_acl *ceph_get_acl(struct inode *, int);
-int ceph_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+int ceph_set_acl(struct user_namespace *mnt_userns,
+		 struct inode *inode, struct posix_acl *acl, int type);
 int ceph_pre_init_acls(struct inode *dir, umode_t *mode,
 		       struct ceph_acl_sec_ctx *as_ctx);
 void ceph_init_inode_acls(struct inode *inode,
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 24997982de01..02f59bcb4f27 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -1238,6 +1238,7 @@ static int ceph_get_xattr_handler(const struct xattr_handler *handler,
 }
 
 static int ceph_set_xattr_handler(const struct xattr_handler *handler,
+				  struct user_namespace *mnt_userns,
 				  struct dentry *unused, struct inode *inode,
 				  const char *name, const void *value,
 				  size_t size, int flags)
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index ab883e84e116..38534e066cc7 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -305,7 +305,8 @@ static long cifs_fallocate(struct file *file, int mode, loff_t off, loff_t len)
 	return -EOPNOTSUPP;
 }
 
-static int cifs_permission(struct inode *inode, int mask)
+static int cifs_permission(struct user_namespace *mnt_userns,
+			   struct inode *inode, int mask)
 {
 	struct cifs_sb_info *cifs_sb;
 
@@ -320,7 +321,7 @@ static int cifs_permission(struct inode *inode, int mask)
 		on the client (above and beyond ACL on servers) for
 		servers which do not support setting and viewing mode bits,
 		so allowing client to check permissions is useful */
-		return generic_permission(inode, mask);
+		return generic_permission(&init_user_ns, inode, mask);
 }
 
 static struct kmem_cache *cifs_inode_cachep;
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 2307bb0f6147..71e9c6abb2a6 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -62,19 +62,22 @@ extern void cifs_sb_deactive(struct super_block *sb);
 /* Functions related to inodes */
 extern const struct inode_operations cifs_dir_inode_ops;
 extern struct inode *cifs_root_iget(struct super_block *);
-extern int cifs_create(struct inode *, struct dentry *, umode_t,
-		       bool excl);
+extern int cifs_create(struct user_namespace *, struct inode *,
+		       struct dentry *, umode_t, bool excl);
 extern int cifs_atomic_open(struct inode *, struct dentry *,
 			    struct file *, unsigned, umode_t);
 extern struct dentry *cifs_lookup(struct inode *, struct dentry *,
 				  unsigned int);
 extern int cifs_unlink(struct inode *dir, struct dentry *dentry);
 extern int cifs_hardlink(struct dentry *, struct inode *, struct dentry *);
-extern int cifs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
-extern int cifs_mkdir(struct inode *, struct dentry *, umode_t);
+extern int cifs_mknod(struct user_namespace *, struct inode *, struct dentry *,
+		      umode_t, dev_t);
+extern int cifs_mkdir(struct user_namespace *, struct inode *, struct dentry *,
+		      umode_t);
 extern int cifs_rmdir(struct inode *, struct dentry *);
-extern int cifs_rename2(struct inode *, struct dentry *, struct inode *,
-			struct dentry *, unsigned int);
+extern int cifs_rename2(struct user_namespace *, struct inode *,
+			struct dentry *, struct inode *, struct dentry *,
+			unsigned int);
 extern int cifs_revalidate_file_attr(struct file *filp);
 extern int cifs_revalidate_dentry_attr(struct dentry *);
 extern int cifs_revalidate_file(struct file *filp);
@@ -82,8 +85,10 @@ extern int cifs_revalidate_dentry(struct dentry *);
 extern int cifs_invalidate_mapping(struct inode *inode);
 extern int cifs_revalidate_mapping(struct inode *inode);
 extern int cifs_zap_mapping(struct inode *inode);
-extern int cifs_getattr(const struct path *, struct kstat *, u32, unsigned int);
-extern int cifs_setattr(struct dentry *, struct iattr *);
+extern int cifs_getattr(struct user_namespace *, const struct path *,
+			struct kstat *, u32, unsigned int);
+extern int cifs_setattr(struct user_namespace *, struct dentry *,
+			struct iattr *);
 extern int cifs_fiemap(struct inode *, struct fiemap_extent_info *, u64 start,
 		       u64 len);
 
@@ -132,8 +137,8 @@ extern struct vfsmount *cifs_dfs_d_automount(struct path *path);
 /* Functions related to symlinks */
 extern const char *cifs_get_link(struct dentry *, struct inode *,
 			struct delayed_call *);
-extern int cifs_symlink(struct inode *inode, struct dentry *direntry,
-			const char *symname);
+extern int cifs_symlink(struct user_namespace *mnt_userns, struct inode *inode,
+			struct dentry *direntry, const char *symname);
 
 #ifdef CONFIG_CIFS_XATTR
 extern const struct xattr_handler *cifs_xattr_handlers[];
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 97ac363b5df1..a3fb81e0ba17 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -567,8 +567,8 @@ out_free_xid:
 	return rc;
 }
 
-int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
-		bool excl)
+int cifs_create(struct user_namespace *mnt_userns, struct inode *inode,
+		struct dentry *direntry, umode_t mode, bool excl)
 {
 	int rc;
 	unsigned int xid = get_xid();
@@ -611,8 +611,8 @@ out_free_xid:
 	return rc;
 }
 
-int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
-		dev_t device_number)
+int cifs_mknod(struct user_namespace *mnt_userns, struct inode *inode,
+	       struct dentry *direntry, umode_t mode, dev_t device_number)
 {
 	int rc = -EPERM;
 	unsigned int xid;
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index a83b3a8ffaac..3e9c7bb23f26 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1857,7 +1857,8 @@ posix_mkdir_get_info:
 	goto posix_mkdir_out;
 }
 
-int cifs_mkdir(struct inode *inode, struct dentry *direntry, umode_t mode)
+int cifs_mkdir(struct user_namespace *mnt_userns, struct inode *inode,
+	       struct dentry *direntry, umode_t mode)
 {
 	int rc = 0;
 	unsigned int xid;
@@ -2067,9 +2068,9 @@ do_rename_exit:
 }
 
 int
-cifs_rename2(struct inode *source_dir, struct dentry *source_dentry,
-	     struct inode *target_dir, struct dentry *target_dentry,
-	     unsigned int flags)
+cifs_rename2(struct user_namespace *mnt_userns, struct inode *source_dir,
+	     struct dentry *source_dentry, struct inode *target_dir,
+	     struct dentry *target_dentry, unsigned int flags)
 {
 	char *from_name = NULL;
 	char *to_name = NULL;
@@ -2370,8 +2371,8 @@ int cifs_revalidate_dentry(struct dentry *dentry)
 	return cifs_revalidate_mapping(inode);
 }
 
-int cifs_getattr(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int flags)
+int cifs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct dentry *dentry = path->dentry;
 	struct cifs_sb_info *cifs_sb = CIFS_SB(dentry->d_sb);
@@ -2408,7 +2409,7 @@ int cifs_getattr(const struct path *path, struct kstat *stat,
 			return rc;
 	}
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	stat->blksize = cifs_sb->ctx->bsize;
 	stat->ino = CIFS_I(inode)->uniqueid;
 
@@ -2610,7 +2611,7 @@ cifs_setattr_unix(struct dentry *direntry, struct iattr *attrs)
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM)
 		attrs->ia_valid |= ATTR_FORCE;
 
-	rc = setattr_prepare(direntry, attrs);
+	rc = setattr_prepare(&init_user_ns, direntry, attrs);
 	if (rc < 0)
 		goto out;
 
@@ -2715,7 +2716,7 @@ cifs_setattr_unix(struct dentry *direntry, struct iattr *attrs)
 	    attrs->ia_size != i_size_read(inode))
 		truncate_setsize(inode, attrs->ia_size);
 
-	setattr_copy(inode, attrs);
+	setattr_copy(&init_user_ns, inode, attrs);
 	mark_inode_dirty(inode);
 
 	/* force revalidate when any of these times are set since some
@@ -2757,7 +2758,7 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs)
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM)
 		attrs->ia_valid |= ATTR_FORCE;
 
-	rc = setattr_prepare(direntry, attrs);
+	rc = setattr_prepare(&init_user_ns, direntry, attrs);
 	if (rc < 0) {
 		free_xid(xid);
 		return rc;
@@ -2913,7 +2914,7 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs)
 	    attrs->ia_size != i_size_read(inode))
 		truncate_setsize(inode, attrs->ia_size);
 
-	setattr_copy(inode, attrs);
+	setattr_copy(&init_user_ns, inode, attrs);
 	mark_inode_dirty(inode);
 
 cifs_setattr_exit:
@@ -2923,7 +2924,8 @@ cifs_setattr_exit:
 }
 
 int
-cifs_setattr(struct dentry *direntry, struct iattr *attrs)
+cifs_setattr(struct user_namespace *mnt_userns, struct dentry *direntry,
+	     struct iattr *attrs)
 {
 	struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 	struct cifs_tcon *pTcon = cifs_sb_master_tcon(cifs_sb);
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 94dab4309fbb..7c5878a645d9 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -661,7 +661,8 @@ cifs_get_link(struct dentry *direntry, struct inode *inode,
 }
 
 int
-cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
+cifs_symlink(struct user_namespace *mnt_userns, struct inode *inode,
+	     struct dentry *direntry, const char *symname)
 {
 	int rc = -EOPNOTSUPP;
 	unsigned int xid;
diff --git a/fs/cifs/xattr.c b/fs/cifs/xattr.c
index 6b658a1172ef..41a611e76bb7 100644
--- a/fs/cifs/xattr.c
+++ b/fs/cifs/xattr.c
@@ -101,6 +101,7 @@ static int cifs_creation_time_set(unsigned int xid, struct cifs_tcon *pTcon,
 }
 
 static int cifs_xattr_set(const struct xattr_handler *handler,
+			  struct user_namespace *mnt_userns,
 			  struct dentry *dentry, struct inode *inode,
 			  const char *name, const void *value,
 			  size_t size, int flags)
diff --git a/fs/coda/coda_linux.h b/fs/coda/coda_linux.h
index d5ebd36fb2cc..e7b27754ce78 100644
--- a/fs/coda/coda_linux.h
+++ b/fs/coda/coda_linux.h
@@ -46,10 +46,12 @@ extern const struct file_operations coda_ioctl_operations;
 /* operations shared over more than one file */
 int coda_open(struct inode *i, struct file *f);
 int coda_release(struct inode *i, struct file *f);
-int coda_permission(struct inode *inode, int mask);
+int coda_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		    int mask);
 int coda_revalidate_inode(struct inode *);
-int coda_getattr(const struct path *, struct kstat *, u32, unsigned int);
-int coda_setattr(struct dentry *, struct iattr *);
+int coda_getattr(struct user_namespace *, const struct path *, struct kstat *,
+		 u32, unsigned int);
+int coda_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 
 /* this file:  heloers */
 char *coda_f2s(struct CodaFid *f);
diff --git a/fs/coda/dir.c b/fs/coda/dir.c
index ca40c2556ba6..d69989c1bac3 100644
--- a/fs/coda/dir.c
+++ b/fs/coda/dir.c
@@ -73,7 +73,8 @@ static struct dentry *coda_lookup(struct inode *dir, struct dentry *entry, unsig
 }
 
 
-int coda_permission(struct inode *inode, int mask)
+int coda_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		    int mask)
 {
 	int error;
 
@@ -132,7 +133,8 @@ static inline void coda_dir_drop_nlink(struct inode *dir)
 }
 
 /* creation routines: create, mknod, mkdir, link, symlink */
-static int coda_create(struct inode *dir, struct dentry *de, umode_t mode, bool excl)
+static int coda_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *de, umode_t mode, bool excl)
 {
 	int error;
 	const char *name=de->d_name.name;
@@ -164,7 +166,8 @@ err_out:
 	return error;
 }
 
-static int coda_mkdir(struct inode *dir, struct dentry *de, umode_t mode)
+static int coda_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *de, umode_t mode)
 {
 	struct inode *inode;
 	struct coda_vattr attrs;
@@ -225,7 +228,8 @@ static int coda_link(struct dentry *source_de, struct inode *dir_inode,
 }
 
 
-static int coda_symlink(struct inode *dir_inode, struct dentry *de,
+static int coda_symlink(struct user_namespace *mnt_userns,
+			struct inode *dir_inode, struct dentry *de,
 			const char *symname)
 {
 	const char *name = de->d_name.name;
@@ -291,9 +295,9 @@ static int coda_rmdir(struct inode *dir, struct dentry *de)
 }
 
 /* rename */
-static int coda_rename(struct inode *old_dir, struct dentry *old_dentry,
-		       struct inode *new_dir, struct dentry *new_dentry,
-		       unsigned int flags)
+static int coda_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
 {
 	const char *old_name = old_dentry->d_name.name;
 	const char *new_name = new_dentry->d_name.name;
diff --git a/fs/coda/inode.c b/fs/coda/inode.c
index b1c70e2b9b1e..d9f1bd7153df 100644
--- a/fs/coda/inode.c
+++ b/fs/coda/inode.c
@@ -251,16 +251,17 @@ static void coda_evict_inode(struct inode *inode)
 	coda_cache_clear_inode(inode);
 }
 
-int coda_getattr(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int flags)
+int coda_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	int err = coda_revalidate_inode(d_inode(path->dentry));
 	if (!err)
-		generic_fillattr(d_inode(path->dentry), stat);
+		generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
 	return err;
 }
 
-int coda_setattr(struct dentry *de, struct iattr *iattr)
+int coda_setattr(struct user_namespace *mnt_userns, struct dentry *de,
+		 struct iattr *iattr)
 {
 	struct inode *inode = d_inode(de);
 	struct coda_vattr vattr;
diff --git a/fs/coda/pioctl.c b/fs/coda/pioctl.c
index 3aec27e5eb82..cb9fd59a688c 100644
--- a/fs/coda/pioctl.c
+++ b/fs/coda/pioctl.c
@@ -24,7 +24,8 @@
 #include "coda_linux.h"
 
 /* pioctl ops */
-static int coda_ioctl_permission(struct inode *inode, int mask);
+static int coda_ioctl_permission(struct user_namespace *mnt_userns,
+				 struct inode *inode, int mask);
 static long coda_pioctl(struct file *filp, unsigned int cmd,
 			unsigned long user_data);
 
@@ -40,7 +41,8 @@ const struct file_operations coda_ioctl_operations = {
 };
 
 /* the coda pioctl inode ops */
-static int coda_ioctl_permission(struct inode *inode, int mask)
+static int coda_ioctl_permission(struct user_namespace *mnt_userns,
+				 struct inode *inode, int mask)
 {
 	return (mask & MAY_EXEC) ? -EACCES : 0;
 }
diff --git a/fs/configfs/configfs_internal.h b/fs/configfs/configfs_internal.h
index 22dce2d35a4b..9a3aed249692 100644
--- a/fs/configfs/configfs_internal.h
+++ b/fs/configfs/configfs_internal.h
@@ -79,7 +79,8 @@ extern void configfs_hash_and_remove(struct dentry * dir, const char * name);
 
 extern const unsigned char * configfs_get_name(struct configfs_dirent *sd);
 extern void configfs_drop_dentry(struct configfs_dirent *sd, struct dentry *parent);
-extern int configfs_setattr(struct dentry *dentry, struct iattr *iattr);
+extern int configfs_setattr(struct user_namespace *mnt_userns,
+			    struct dentry *dentry, struct iattr *iattr);
 
 extern struct dentry *configfs_pin_fs(void);
 extern void configfs_release_fs(void);
@@ -92,7 +93,8 @@ extern const struct inode_operations configfs_root_inode_operations;
 extern const struct inode_operations configfs_symlink_inode_operations;
 extern const struct dentry_operations configfs_dentry_ops;
 
-extern int configfs_symlink(struct inode *dir, struct dentry *dentry,
+extern int configfs_symlink(struct user_namespace *mnt_userns,
+			    struct inode *dir, struct dentry *dentry,
 			    const char *symname);
 extern int configfs_unlink(struct inode *dir, struct dentry *dentry);
 
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index b839dd1b459f..b6098e02e20b 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -1268,7 +1268,8 @@ out_root_unlock:
 }
 EXPORT_SYMBOL(configfs_depend_item_unlocked);
 
-static int configfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int configfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode)
 {
 	int ret = 0;
 	int module_got = 0;
diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c
index 8bd6a883c94c..42c348bb2903 100644
--- a/fs/configfs/inode.c
+++ b/fs/configfs/inode.c
@@ -40,7 +40,8 @@ static const struct inode_operations configfs_inode_operations ={
 	.setattr	= configfs_setattr,
 };
 
-int configfs_setattr(struct dentry * dentry, struct iattr * iattr)
+int configfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		     struct iattr *iattr)
 {
 	struct inode * inode = d_inode(dentry);
 	struct configfs_dirent * sd = dentry->d_fsdata;
@@ -67,7 +68,7 @@ int configfs_setattr(struct dentry * dentry, struct iattr * iattr)
 	}
 	/* attributes were changed atleast once in past */
 
-	error = simple_setattr(dentry, iattr);
+	error = simple_setattr(mnt_userns, dentry, iattr);
 	if (error)
 		return error;
 
diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c
index cb61467478ca..77c854364e60 100644
--- a/fs/configfs/symlink.c
+++ b/fs/configfs/symlink.c
@@ -139,7 +139,8 @@ static int get_target(const char *symname, struct path *path,
 }
 
 
-int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+int configfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, const char *symname)
 {
 	int ret;
 	struct path path;
@@ -197,7 +198,8 @@ int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symna
 	if (dentry->d_inode || d_unhashed(dentry))
 		ret = -EEXIST;
 	else
-		ret = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+		ret = inode_permission(&init_user_ns, dir,
+				       MAY_WRITE | MAY_EXEC);
 	if (!ret)
 		ret = type->ct_item_ops->allow_link(parent_item, target_item);
 	if (!ret) {
diff --git a/fs/coredump.c b/fs/coredump.c
index a2f6ecc8e345..ae778937a1ff 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -703,6 +703,7 @@ void do_coredump(const kernel_siginfo_t *siginfo)
 			goto close_fail;
 		}
 	} else {
+		struct user_namespace *mnt_userns;
 		struct inode *inode;
 		int open_flags = O_CREAT | O_RDWR | O_NOFOLLOW |
 				 O_LARGEFILE | O_EXCL;
@@ -780,13 +781,15 @@ void do_coredump(const kernel_siginfo_t *siginfo)
 		 * a process dumps core while its cwd is e.g. on a vfat
 		 * filesystem.
 		 */
-		if (!uid_eq(inode->i_uid, current_fsuid()))
+		mnt_userns = file_mnt_user_ns(cprm.file);
+		if (!uid_eq(i_uid_into_mnt(mnt_userns, inode), current_fsuid()))
 			goto close_fail;
 		if ((inode->i_mode & 0677) != 0600)
 			goto close_fail;
 		if (!(cprm.file->f_mode & FMODE_CAN_WRITE))
 			goto close_fail;
-		if (do_truncate(cprm.file->f_path.dentry, 0, 0, cprm.file))
+		if (do_truncate(mnt_userns, cprm.file->f_path.dentry,
+				0, 0, cprm.file))
 			goto close_fail;
 	}
 
@@ -931,7 +934,8 @@ void dump_truncate(struct coredump_params *cprm)
 	if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
 		offset = file->f_op->llseek(file, 0, SEEK_CUR);
 		if (i_size_read(file->f_mapping->host) < offset)
-			do_truncate(file->f_path.dentry, offset, 0, file);
+			do_truncate(file_mnt_user_ns(file), file->f_path.dentry,
+				    offset, 0, file);
 	}
 }
 EXPORT_SYMBOL(dump_truncate);
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index a51cef6bd27f..ed3d623724cd 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -465,7 +465,7 @@ int fscrypt_ioctl_set_policy(struct file *filp, const void __user *arg)
 		return -EFAULT;
 	policy.version = version;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	ret = mnt_want_write_file(filp);
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 2fcf66473436..c35249497b9b 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -42,13 +42,14 @@ static unsigned int debugfs_allow = DEFAULT_DEBUGFS_ALLOW_BITS;
  * so that we can use the file mode as part of a heuristic to determine whether
  * to lock down individual files.
  */
-static int debugfs_setattr(struct dentry *dentry, struct iattr *ia)
+static int debugfs_setattr(struct user_namespace *mnt_userns,
+			   struct dentry *dentry, struct iattr *ia)
 {
 	int ret = security_locked_down(LOCKDOWN_DEBUGFS);
 
 	if (ret && (ia->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)))
 		return ret;
-	return simple_setattr(dentry, ia);
+	return simple_setattr(&init_user_ns, dentry, ia);
 }
 
 static const struct inode_operations debugfs_file_inode_operations = {
@@ -775,8 +776,8 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
 
 	take_dentry_name_snapshot(&old_name, old_dentry);
 
-	error = simple_rename(d_inode(old_dir), old_dentry, d_inode(new_dir),
-			      dentry, 0);
+	error = simple_rename(&init_user_ns, d_inode(old_dir), old_dentry,
+			      d_inode(new_dir), dentry, 0);
 	if (error) {
 		release_dentry_name_snapshot(&old_name);
 		goto exit;
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index 0681540c48d9..943e523f4c9d 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1110,8 +1110,8 @@ ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry,
 	}
 
 	inode_lock(lower_inode);
-	rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME,
-			    page_virt, size, 0);
+	rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode,
+			    ECRYPTFS_XATTR_NAME, page_virt, size, 0);
 	if (!rc && ecryptfs_inode)
 		fsstack_copy_attr_all(ecryptfs_inode, lower_inode);
 	inode_unlock(lower_inode);
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 58d0f7187997..18e9285fbb4c 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -141,7 +141,8 @@ static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry,
 	else if (d_unhashed(lower_dentry))
 		rc = -EINVAL;
 	else
-		rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL);
+		rc = vfs_unlink(&init_user_ns, lower_dir_inode, lower_dentry,
+				NULL);
 	if (rc) {
 		printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
 		goto out_unlock;
@@ -180,7 +181,8 @@ ecryptfs_do_create(struct inode *directory_inode,
 
 	lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
 	lower_dir_dentry = lock_parent(lower_dentry);
-	rc = vfs_create(d_inode(lower_dir_dentry), lower_dentry, mode, true);
+	rc = vfs_create(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
+			mode, true);
 	if (rc) {
 		printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
 		       "rc = [%d]\n", __func__, rc);
@@ -190,7 +192,8 @@ ecryptfs_do_create(struct inode *directory_inode,
 	inode = __ecryptfs_get_inode(d_inode(lower_dentry),
 				     directory_inode->i_sb);
 	if (IS_ERR(inode)) {
-		vfs_unlink(d_inode(lower_dir_dentry), lower_dentry, NULL);
+		vfs_unlink(&init_user_ns, d_inode(lower_dir_dentry),
+			   lower_dentry, NULL);
 		goto out_lock;
 	}
 	fsstack_copy_attr_times(directory_inode, d_inode(lower_dir_dentry));
@@ -254,7 +257,8 @@ out:
  * Returns zero on success; non-zero on error condition
  */
 static int
-ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry,
+ecryptfs_create(struct user_namespace *mnt_userns,
+		struct inode *directory_inode, struct dentry *ecryptfs_dentry,
 		umode_t mode, bool excl)
 {
 	struct inode *ecryptfs_inode;
@@ -436,8 +440,8 @@ static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
 	dget(lower_old_dentry);
 	dget(lower_new_dentry);
 	lower_dir_dentry = lock_parent(lower_new_dentry);
-	rc = vfs_link(lower_old_dentry, d_inode(lower_dir_dentry),
-		      lower_new_dentry, NULL);
+	rc = vfs_link(lower_old_dentry, &init_user_ns,
+		      d_inode(lower_dir_dentry), lower_new_dentry, NULL);
 	if (rc || d_really_is_negative(lower_new_dentry))
 		goto out_lock;
 	rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
@@ -460,7 +464,8 @@ static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
 	return ecryptfs_do_unlink(dir, dentry, d_inode(dentry));
 }
 
-static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
+static int ecryptfs_symlink(struct user_namespace *mnt_userns,
+			    struct inode *dir, struct dentry *dentry,
 			    const char *symname)
 {
 	int rc;
@@ -481,7 +486,7 @@ static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
 						  strlen(symname));
 	if (rc)
 		goto out_lock;
-	rc = vfs_symlink(d_inode(lower_dir_dentry), lower_dentry,
+	rc = vfs_symlink(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
 			 encoded_symname);
 	kfree(encoded_symname);
 	if (rc || d_really_is_negative(lower_dentry))
@@ -499,7 +504,8 @@ out_lock:
 	return rc;
 }
 
-static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ecryptfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode)
 {
 	int rc;
 	struct dentry *lower_dentry;
@@ -507,7 +513,8 @@ static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode
 
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	lower_dir_dentry = lock_parent(lower_dentry);
-	rc = vfs_mkdir(d_inode(lower_dir_dentry), lower_dentry, mode);
+	rc = vfs_mkdir(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
+		       mode);
 	if (rc || d_really_is_negative(lower_dentry))
 		goto out;
 	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
@@ -541,7 +548,7 @@ static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
 	else if (d_unhashed(lower_dentry))
 		rc = -EINVAL;
 	else
-		rc = vfs_rmdir(lower_dir_inode, lower_dentry);
+		rc = vfs_rmdir(&init_user_ns, lower_dir_inode, lower_dentry);
 	if (!rc) {
 		clear_nlink(d_inode(dentry));
 		fsstack_copy_attr_times(dir, lower_dir_inode);
@@ -555,7 +562,8 @@ static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
 }
 
 static int
-ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+ecryptfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+	       struct dentry *dentry, umode_t mode, dev_t dev)
 {
 	int rc;
 	struct dentry *lower_dentry;
@@ -563,7 +571,8 @@ ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev
 
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	lower_dir_dentry = lock_parent(lower_dentry);
-	rc = vfs_mknod(d_inode(lower_dir_dentry), lower_dentry, mode, dev);
+	rc = vfs_mknod(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
+		       mode, dev);
 	if (rc || d_really_is_negative(lower_dentry))
 		goto out;
 	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
@@ -579,9 +588,9 @@ out:
 }
 
 static int
-ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		struct inode *new_dir, struct dentry *new_dentry,
-		unsigned int flags)
+ecryptfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		struct dentry *old_dentry, struct inode *new_dir,
+		struct dentry *new_dentry, unsigned int flags)
 {
 	int rc;
 	struct dentry *lower_old_dentry;
@@ -590,6 +599,7 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	struct dentry *lower_new_dir_dentry;
 	struct dentry *trap;
 	struct inode *target_inode;
+	struct renamedata rd = {};
 
 	if (flags)
 		return -EINVAL;
@@ -619,9 +629,14 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 		rc = -ENOTEMPTY;
 		goto out_lock;
 	}
-	rc = vfs_rename(d_inode(lower_old_dir_dentry), lower_old_dentry,
-			d_inode(lower_new_dir_dentry), lower_new_dentry,
-			NULL, 0);
+
+	rd.old_mnt_userns	= &init_user_ns;
+	rd.old_dir		= d_inode(lower_old_dir_dentry);
+	rd.old_dentry		= lower_old_dentry;
+	rd.new_mnt_userns	= &init_user_ns;
+	rd.new_dir		= d_inode(lower_new_dir_dentry);
+	rd.new_dentry		= lower_new_dentry;
+	rc = vfs_rename(&rd);
 	if (rc)
 		goto out_lock;
 	if (target_inode)
@@ -855,16 +870,19 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
 		struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 
 		inode_lock(d_inode(lower_dentry));
-		rc = notify_change(lower_dentry, &lower_ia, NULL);
+		rc = notify_change(&init_user_ns, lower_dentry,
+				   &lower_ia, NULL);
 		inode_unlock(d_inode(lower_dentry));
 	}
 	return rc;
 }
 
 static int
-ecryptfs_permission(struct inode *inode, int mask)
+ecryptfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		    int mask)
 {
-	return inode_permission(ecryptfs_inode_to_lower(inode), mask);
+	return inode_permission(&init_user_ns,
+				ecryptfs_inode_to_lower(inode), mask);
 }
 
 /**
@@ -879,7 +897,8 @@ ecryptfs_permission(struct inode *inode, int mask)
  * All other metadata changes will be passed right to the lower filesystem,
  * and we will just update our inode to look like the lower.
  */
-static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
+static int ecryptfs_setattr(struct user_namespace *mnt_userns,
+			    struct dentry *dentry, struct iattr *ia)
 {
 	int rc = 0;
 	struct dentry *lower_dentry;
@@ -933,7 +952,7 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
 	}
 	mutex_unlock(&crypt_stat->cs_mutex);
 
-	rc = setattr_prepare(dentry, ia);
+	rc = setattr_prepare(&init_user_ns, dentry, ia);
 	if (rc)
 		goto out;
 	if (ia->ia_valid & ATTR_SIZE) {
@@ -959,14 +978,15 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
 		lower_ia.ia_valid &= ~ATTR_MODE;
 
 	inode_lock(d_inode(lower_dentry));
-	rc = notify_change(lower_dentry, &lower_ia, NULL);
+	rc = notify_change(&init_user_ns, lower_dentry, &lower_ia, NULL);
 	inode_unlock(d_inode(lower_dentry));
 out:
 	fsstack_copy_attr_all(inode, lower_inode);
 	return rc;
 }
 
-static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
+static int ecryptfs_getattr_link(struct user_namespace *mnt_userns,
+				 const struct path *path, struct kstat *stat,
 				 u32 request_mask, unsigned int flags)
 {
 	struct dentry *dentry = path->dentry;
@@ -975,7 +995,7 @@ static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
 
 	mount_crypt_stat = &ecryptfs_superblock_to_private(
 						dentry->d_sb)->mount_crypt_stat;
-	generic_fillattr(d_inode(dentry), stat);
+	generic_fillattr(&init_user_ns, d_inode(dentry), stat);
 	if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
 		char *target;
 		size_t targetsiz;
@@ -991,7 +1011,8 @@ static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
 	return rc;
 }
 
-static int ecryptfs_getattr(const struct path *path, struct kstat *stat,
+static int ecryptfs_getattr(struct user_namespace *mnt_userns,
+			    const struct path *path, struct kstat *stat,
 			    u32 request_mask, unsigned int flags)
 {
 	struct dentry *dentry = path->dentry;
@@ -1003,7 +1024,7 @@ static int ecryptfs_getattr(const struct path *path, struct kstat *stat,
 	if (!rc) {
 		fsstack_copy_attr_all(d_inode(dentry),
 				      ecryptfs_inode_to_lower(d_inode(dentry)));
-		generic_fillattr(d_inode(dentry), stat);
+		generic_fillattr(&init_user_ns, d_inode(dentry), stat);
 		stat->blocks = lower_stat.blocks;
 	}
 	return rc;
@@ -1025,7 +1046,7 @@ ecryptfs_setxattr(struct dentry *dentry, struct inode *inode,
 		goto out;
 	}
 	inode_lock(lower_inode);
-	rc = __vfs_setxattr_locked(lower_dentry, name, value, size, flags, NULL);
+	rc = __vfs_setxattr_locked(&init_user_ns, lower_dentry, name, value, size, flags, NULL);
 	inode_unlock(lower_inode);
 	if (!rc && inode)
 		fsstack_copy_attr_all(inode, lower_inode);
@@ -1091,7 +1112,7 @@ static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode,
 		goto out;
 	}
 	inode_lock(lower_inode);
-	rc = __vfs_removexattr(lower_dentry, name);
+	rc = __vfs_removexattr(&init_user_ns, lower_dentry, name);
 	inode_unlock(lower_inode);
 out:
 	return rc;
@@ -1135,6 +1156,7 @@ static int ecryptfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int ecryptfs_xattr_set(const struct xattr_handler *handler,
+			      struct user_namespace *mnt_userns,
 			      struct dentry *dentry, struct inode *inode,
 			      const char *name, const void *value, size_t size,
 			      int flags)
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index e63259fdef28..cdf40a54a35d 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -531,6 +531,12 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
 		goto out_free;
 	}
 
+	if (mnt_user_ns(path.mnt) != &init_user_ns) {
+		rc = -EINVAL;
+		printk(KERN_ERR "Mounting on idmapped mounts currently disallowed\n");
+		goto out_free;
+	}
+
 	if (check_ruid && !uid_eq(d_inode(path.dentry)->i_uid, current_uid())) {
 		rc = -EPERM;
 		printk(KERN_ERR "Mount of device (uid: %d) not owned by "
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 019572c6b39a..2f333a40ff4d 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -426,8 +426,8 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode)
 	if (size < 0)
 		size = 8;
 	put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt);
-	rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME,
-			    xattr_virt, size, 0);
+	rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode,
+			    ECRYPTFS_XATTR_NAME, xattr_virt, size, 0);
 	inode_unlock(lower_inode);
 	if (rc)
 		printk(KERN_ERR "Error whilst attempting to write inode size "
diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c
index feaa5e182b7b..e6bc0302643b 100644
--- a/fs/efivarfs/file.c
+++ b/fs/efivarfs/file.c
@@ -137,7 +137,7 @@ efivarfs_ioc_setxflags(struct file *file, void __user *arg)
 	unsigned int oldflags = efivarfs_getflags(inode);
 	int error;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	if (copy_from_user(&flags, arg, sizeof(flags)))
diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c
index 0297ad95eb5c..14e2947975fd 100644
--- a/fs/efivarfs/inode.c
+++ b/fs/efivarfs/inode.c
@@ -66,8 +66,8 @@ bool efivarfs_valid_name(const char *str, int len)
 	return uuid_is_valid(s);
 }
 
-static int efivarfs_create(struct inode *dir, struct dentry *dentry,
-			  umode_t mode, bool excl)
+static int efivarfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			   struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct inode *inode = NULL;
 	struct efivar_entry *var;
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 3e21c0e8adae..119fdce1b520 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -331,8 +331,9 @@ struct inode *erofs_iget(struct super_block *sb,
 	return inode;
 }
 
-int erofs_getattr(const struct path *path, struct kstat *stat,
-		  u32 request_mask, unsigned int query_flags)
+int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		  struct kstat *stat, u32 request_mask,
+		  unsigned int query_flags)
 {
 	struct inode *const inode = d_inode(path->dentry);
 
@@ -343,7 +344,7 @@ int erofs_getattr(const struct path *path, struct kstat *stat,
 	stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
 				  STATX_ATTR_IMMUTABLE);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	return 0;
 }
 
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 67a7ec945686..351dae524a0c 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -373,8 +373,9 @@ extern const struct inode_operations erofs_symlink_iops;
 extern const struct inode_operations erofs_fast_symlink_iops;
 
 struct inode *erofs_iget(struct super_block *sb, erofs_nid_t nid, bool dir);
-int erofs_getattr(const struct path *path, struct kstat *stat,
-		  u32 request_mask, unsigned int query_flags);
+int erofs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		  struct kstat *stat, u32 request_mask,
+		  unsigned int query_flags);
 
 /* namei.c */
 extern const struct inode_operations erofs_dir_iops;
diff --git a/fs/exec.c b/fs/exec.c
index 5a853f03c233..6f3c02066ce3 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1404,14 +1404,15 @@ EXPORT_SYMBOL(begin_new_exec);
 void would_dump(struct linux_binprm *bprm, struct file *file)
 {
 	struct inode *inode = file_inode(file);
-	if (inode_permission(inode, MAY_READ) < 0) {
+	struct user_namespace *mnt_userns = file_mnt_user_ns(file);
+	if (inode_permission(mnt_userns, inode, MAY_READ) < 0) {
 		struct user_namespace *old, *user_ns;
 		bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
 
 		/* Ensure mm->user_ns contains the executable */
 		user_ns = old = bprm->mm->user_ns;
 		while ((user_ns != &init_user_ns) &&
-		       !privileged_wrt_inode_uidgid(user_ns, inode))
+		       !privileged_wrt_inode_uidgid(user_ns, mnt_userns, inode))
 			user_ns = user_ns->parent;
 
 		if (old != user_ns) {
@@ -1579,6 +1580,7 @@ static void check_unsafe_exec(struct linux_binprm *bprm)
 static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)
 {
 	/* Handle suid and sgid on files */
+	struct user_namespace *mnt_userns;
 	struct inode *inode;
 	unsigned int mode;
 	kuid_t uid;
@@ -1595,13 +1597,15 @@ static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)
 	if (!(mode & (S_ISUID|S_ISGID)))
 		return;
 
+	mnt_userns = file_mnt_user_ns(file);
+
 	/* Be careful if suid/sgid is set */
 	inode_lock(inode);
 
 	/* reload atomically mode/uid/gid now that lock held */
 	mode = inode->i_mode;
-	uid = inode->i_uid;
-	gid = inode->i_gid;
+	uid = i_uid_into_mnt(mnt_userns, inode);
+	gid = i_gid_into_mnt(mnt_userns, inode);
 	inode_unlock(inode);
 
 	/* We ignore suid/sgid if there are no mappings for them in the ns */
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index 764bc645241e..fa21421a14d9 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -416,9 +416,11 @@ int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count);
 extern const struct file_operations exfat_file_operations;
 int __exfat_truncate(struct inode *inode, loff_t new_size);
 void exfat_truncate(struct inode *inode, loff_t size);
-int exfat_setattr(struct dentry *dentry, struct iattr *attr);
-int exfat_getattr(const struct path *path, struct kstat *stat,
-		unsigned int request_mask, unsigned int query_flags);
+int exfat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *attr);
+int exfat_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		  struct kstat *stat, unsigned int request_mask,
+		  unsigned int query_flags);
 int exfat_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
 
 /* namei.c */
diff --git a/fs/exfat/file.c b/fs/exfat/file.c
index 183ffdf4d43c..f783cf38dd8e 100644
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -267,13 +267,14 @@ write_size:
 	mutex_unlock(&sbi->s_lock);
 }
 
-int exfat_getattr(const struct path *path, struct kstat *stat,
-		unsigned int request_mask, unsigned int query_flags)
+int exfat_getattr(struct user_namespace *mnt_uerns, const struct path *path,
+		  struct kstat *stat, unsigned int request_mask,
+		  unsigned int query_flags)
 {
 	struct inode *inode = d_backing_inode(path->dentry);
 	struct exfat_inode_info *ei = EXFAT_I(inode);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	exfat_truncate_atime(&stat->atime);
 	stat->result_mask |= STATX_BTIME;
 	stat->btime.tv_sec = ei->i_crtime.tv_sec;
@@ -282,7 +283,8 @@ int exfat_getattr(const struct path *path, struct kstat *stat,
 	return 0;
 }
 
-int exfat_setattr(struct dentry *dentry, struct iattr *attr)
+int exfat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *attr)
 {
 	struct exfat_sb_info *sbi = EXFAT_SB(dentry->d_sb);
 	struct inode *inode = dentry->d_inode;
@@ -305,7 +307,7 @@ int exfat_setattr(struct dentry *dentry, struct iattr *attr)
 				ATTR_TIMES_SET);
 	}
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	attr->ia_valid = ia_valid;
 	if (error)
 		goto out;
@@ -340,7 +342,7 @@ int exfat_setattr(struct dentry *dentry, struct iattr *attr)
 		up_write(&EXFAT_I(inode)->truncate_lock);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	exfat_truncate_atime(&inode->i_atime);
 	mark_inode_dirty(inode);
 
diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
index 2932b23a3b6c..d9e8ec689c55 100644
--- a/fs/exfat/namei.c
+++ b/fs/exfat/namei.c
@@ -541,8 +541,8 @@ out:
 	return ret;
 }
 
-static int exfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		bool excl)
+static int exfat_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct super_block *sb = dir->i_sb;
 	struct inode *inode;
@@ -827,7 +827,8 @@ unlock:
 	return err;
 }
 
-static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int exfat_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct super_block *sb = dir->i_sb;
 	struct inode *inode;
@@ -1318,9 +1319,10 @@ out:
 	return ret;
 }
 
-static int exfat_rename(struct inode *old_dir, struct dentry *old_dentry,
-		struct inode *new_dir, struct dentry *new_dentry,
-		unsigned int flags)
+static int exfat_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry,
+			unsigned int flags)
 {
 	struct inode *old_inode, *new_inode;
 	struct super_block *sb = old_dir->i_sb;
diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c
index cf4c77f8dd08..b9a9db98e94b 100644
--- a/fs/ext2/acl.c
+++ b/fs/ext2/acl.c
@@ -216,14 +216,16 @@ __ext2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
  * inode->i_mutex: down
  */
 int
-ext2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+ext2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+	     struct posix_acl *acl, int type)
 {
 	int error;
 	int update_mode = 0;
 	umode_t mode = inode->i_mode;
 
 	if (type == ACL_TYPE_ACCESS && acl) {
-		error = posix_acl_update_mode(inode, &mode, &acl);
+		error = posix_acl_update_mode(&init_user_ns, inode, &mode,
+					      &acl);
 		if (error)
 			return error;
 		update_mode = 1;
diff --git a/fs/ext2/acl.h b/fs/ext2/acl.h
index 0f01c759daac..917db5f6630a 100644
--- a/fs/ext2/acl.h
+++ b/fs/ext2/acl.h
@@ -56,7 +56,8 @@ static inline int ext2_acl_count(size_t size)
 
 /* acl.c */
 extern struct posix_acl *ext2_get_acl(struct inode *inode, int type);
-extern int ext2_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+extern int ext2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+			struct posix_acl *acl, int type);
 extern int ext2_init_acl (struct inode *, struct inode *);
 
 #else
diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index 2a4175fbaf5e..3309fb2d327a 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -764,8 +764,9 @@ extern struct inode *ext2_iget (struct super_block *, unsigned long);
 extern int ext2_write_inode (struct inode *, struct writeback_control *);
 extern void ext2_evict_inode(struct inode *);
 extern int ext2_get_block(struct inode *, sector_t, struct buffer_head *, int);
-extern int ext2_setattr (struct dentry *, struct iattr *);
-extern int ext2_getattr (const struct path *, struct kstat *, u32, unsigned int);
+extern int ext2_setattr (struct user_namespace *, struct dentry *, struct iattr *);
+extern int ext2_getattr (struct user_namespace *, const struct path *,
+			 struct kstat *, u32, unsigned int);
 extern void ext2_set_inode_flags(struct inode *inode);
 extern int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		       u64 start, u64 len);
diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c
index 432c3febea6d..df14e750e9fe 100644
--- a/fs/ext2/ialloc.c
+++ b/fs/ext2/ialloc.c
@@ -551,7 +551,7 @@ got:
 		inode->i_uid = current_fsuid();
 		inode->i_gid = dir->i_gid;
 	} else
-		inode_init_owner(inode, dir, mode);
+		inode_init_owner(&init_user_ns, inode, dir, mode);
 
 	inode->i_ino = ino;
 	inode->i_blocks = 0;
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 78c417d3c898..68178b2234bd 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -1638,8 +1638,8 @@ int ext2_write_inode(struct inode *inode, struct writeback_control *wbc)
 	return __ext2_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
 }
 
-int ext2_getattr(const struct path *path, struct kstat *stat,
-		u32 request_mask, unsigned int query_flags)
+int ext2_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct ext2_inode_info *ei = EXT2_I(inode);
@@ -1660,16 +1660,17 @@ int ext2_getattr(const struct path *path, struct kstat *stat,
 			STATX_ATTR_IMMUTABLE |
 			STATX_ATTR_NODUMP);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	return 0;
 }
 
-int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
+int ext2_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *iattr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
 
-	error = setattr_prepare(dentry, iattr);
+	error = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (error)
 		return error;
 
@@ -1689,9 +1690,9 @@ int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
 		if (error)
 			return error;
 	}
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 	if (iattr->ia_valid & ATTR_MODE)
-		error = posix_acl_chmod(inode, inode->i_mode);
+		error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
 	mark_inode_dirty(inode);
 
 	return error;
diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
index 32a8d10b579d..b399cbb7022d 100644
--- a/fs/ext2/ioctl.c
+++ b/fs/ext2/ioctl.c
@@ -39,7 +39,7 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		if (ret)
 			return ret;
 
-		if (!inode_owner_or_capable(inode)) {
+		if (!inode_owner_or_capable(&init_user_ns, inode)) {
 			ret = -EACCES;
 			goto setflags_out;
 		}
@@ -84,7 +84,7 @@ setflags_out:
 	case EXT2_IOC_SETVERSION: {
 		__u32 generation;
 
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(&init_user_ns, inode))
 			return -EPERM;
 		ret = mnt_want_write_file(filp);
 		if (ret)
@@ -117,7 +117,7 @@ setversion_out:
 		if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
 			return -ENOTTY;
 
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(&init_user_ns, inode))
 			return -EACCES;
 
 		if (get_user(rsv_window_size, (int __user *)arg))
diff --git a/fs/ext2/namei.c b/fs/ext2/namei.c
index ea980f1e2e99..3367384d344d 100644
--- a/fs/ext2/namei.c
+++ b/fs/ext2/namei.c
@@ -100,7 +100,9 @@ struct dentry *ext2_get_parent(struct dentry *child)
  * If the create succeeds, we fill in the inode information
  * with d_instantiate(). 
  */
-static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
+static int ext2_create (struct user_namespace * mnt_userns,
+			struct inode * dir, struct dentry * dentry,
+			umode_t mode, bool excl)
 {
 	struct inode *inode;
 	int err;
@@ -118,7 +120,8 @@ static int ext2_create (struct inode * dir, struct dentry * dentry, umode_t mode
 	return ext2_add_nondir(dentry, inode);
 }
 
-static int ext2_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ext2_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode = ext2_new_inode(dir, mode, NULL);
 	if (IS_ERR(inode))
@@ -131,7 +134,8 @@ static int ext2_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 	return 0;
 }
 
-static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
+static int ext2_mknod (struct user_namespace * mnt_userns, struct inode * dir,
+	struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct inode * inode;
 	int err;
@@ -151,8 +155,8 @@ static int ext2_mknod (struct inode * dir, struct dentry *dentry, umode_t mode,
 	return err;
 }
 
-static int ext2_symlink (struct inode * dir, struct dentry * dentry,
-	const char * symname)
+static int ext2_symlink (struct user_namespace * mnt_userns, struct inode * dir,
+	struct dentry * dentry, const char * symname)
 {
 	struct super_block * sb = dir->i_sb;
 	int err = -ENAMETOOLONG;
@@ -225,7 +229,8 @@ static int ext2_link (struct dentry * old_dentry, struct inode * dir,
 	return err;
 }
 
-static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
+static int ext2_mkdir(struct user_namespace * mnt_userns,
+	struct inode * dir, struct dentry * dentry, umode_t mode)
 {
 	struct inode * inode;
 	int err;
@@ -315,8 +320,9 @@ static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
 	return err;
 }
 
-static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
-			struct inode * new_dir,	struct dentry * new_dentry,
+static int ext2_rename (struct user_namespace * mnt_userns,
+			struct inode * old_dir, struct dentry * old_dentry,
+			struct inode * new_dir, struct dentry * new_dentry,
 			unsigned int flags)
 {
 	struct inode * old_inode = d_inode(old_dentry);
diff --git a/fs/ext2/xattr_security.c b/fs/ext2/xattr_security.c
index 9a682e440acb..ebade1f52451 100644
--- a/fs/ext2/xattr_security.c
+++ b/fs/ext2/xattr_security.c
@@ -19,6 +19,7 @@ ext2_xattr_security_get(const struct xattr_handler *handler,
 
 static int
 ext2_xattr_security_set(const struct xattr_handler *handler,
+			struct user_namespace *mnt_userns,
 			struct dentry *unused, struct inode *inode,
 			const char *name, const void *value,
 			size_t size, int flags)
diff --git a/fs/ext2/xattr_trusted.c b/fs/ext2/xattr_trusted.c
index 49add1107850..18a87d5dd1ab 100644
--- a/fs/ext2/xattr_trusted.c
+++ b/fs/ext2/xattr_trusted.c
@@ -26,6 +26,7 @@ ext2_xattr_trusted_get(const struct xattr_handler *handler,
 
 static int
 ext2_xattr_trusted_set(const struct xattr_handler *handler,
+		       struct user_namespace *mnt_userns,
 		       struct dentry *unused, struct inode *inode,
 		       const char *name, const void *value,
 		       size_t size, int flags)
diff --git a/fs/ext2/xattr_user.c b/fs/ext2/xattr_user.c
index c243a3b4d69d..58092449f8ff 100644
--- a/fs/ext2/xattr_user.c
+++ b/fs/ext2/xattr_user.c
@@ -30,6 +30,7 @@ ext2_xattr_user_get(const struct xattr_handler *handler,
 
 static int
 ext2_xattr_user_set(const struct xattr_handler *handler,
+		    struct user_namespace *mnt_userns,
 		    struct dentry *unused, struct inode *inode,
 		    const char *name, const void *value,
 		    size_t size, int flags)
diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
index 68aaed48315f..c5eaffccecc3 100644
--- a/fs/ext4/acl.c
+++ b/fs/ext4/acl.c
@@ -222,7 +222,8 @@ __ext4_set_acl(handle_t *handle, struct inode *inode, int type,
 }
 
 int
-ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+ext4_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+	     struct posix_acl *acl, int type)
 {
 	handle_t *handle;
 	int error, credits, retries = 0;
@@ -245,7 +246,7 @@ retry:
 	ext4_fc_start_update(inode);
 
 	if ((type == ACL_TYPE_ACCESS) && acl) {
-		error = posix_acl_update_mode(inode, &mode, &acl);
+		error = posix_acl_update_mode(mnt_userns, inode, &mode, &acl);
 		if (error)
 			goto out_stop;
 		if (mode != inode->i_mode)
diff --git a/fs/ext4/acl.h b/fs/ext4/acl.h
index 9b63f5416a2f..84b8942a57f2 100644
--- a/fs/ext4/acl.h
+++ b/fs/ext4/acl.h
@@ -56,7 +56,8 @@ static inline int ext4_acl_count(size_t size)
 
 /* acl.c */
 struct posix_acl *ext4_get_acl(struct inode *inode, int type);
-int ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+int ext4_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type);
 extern int ext4_init_acl(handle_t *, struct inode *, struct inode *);
 
 #else  /* CONFIG_EXT4_FS_POSIX_ACL */
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 2866d249f3d2..644fd69185d3 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2755,18 +2755,19 @@ extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
 
 /* ialloc.c */
 extern int ext4_mark_inode_used(struct super_block *sb, int ino);
-extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
+extern struct inode *__ext4_new_inode(struct user_namespace *, handle_t *,
+				      struct inode *, umode_t,
 				      const struct qstr *qstr, __u32 goal,
 				      uid_t *owner, __u32 i_flags,
 				      int handle_type, unsigned int line_no,
 				      int nblocks);
 
-#define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
-	__ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
-			 i_flags, 0, 0, 0)
-#define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
+#define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags)          \
+	__ext4_new_inode(&init_user_ns, (handle), (dir), (mode), (qstr),       \
+			 (goal), (owner), i_flags, 0, 0, 0)
+#define ext4_new_inode_start_handle(mnt_userns, dir, mode, qstr, goal, owner, \
 				    type, nblocks)		    \
-	__ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
+	__ext4_new_inode((mnt_userns), NULL, (dir), (mode), (qstr), (goal), (owner), \
 			 0, (type), __LINE__, (nblocks))
 
 
@@ -2877,11 +2878,14 @@ extern struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
 	__ext4_iget((sb), (ino), (flags), __func__, __LINE__)
 
 extern int  ext4_write_inode(struct inode *, struct writeback_control *);
-extern int  ext4_setattr(struct dentry *, struct iattr *);
-extern int  ext4_getattr(const struct path *, struct kstat *, u32, unsigned int);
+extern int  ext4_setattr(struct user_namespace *, struct dentry *,
+			 struct iattr *);
+extern int  ext4_getattr(struct user_namespace *, const struct path *,
+			 struct kstat *, u32, unsigned int);
 extern void ext4_evict_inode(struct inode *);
 extern void ext4_clear_inode(struct inode *);
-extern int  ext4_file_getattr(const struct path *, struct kstat *, u32, unsigned int);
+extern int  ext4_file_getattr(struct user_namespace *, const struct path *,
+			      struct kstat *, u32, unsigned int);
 extern int  ext4_sync_inode(handle_t *, struct inode *);
 extern void ext4_dirty_inode(struct inode *, int);
 extern int ext4_change_inode_journal_flag(struct inode *, int);
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 20f2fcb799f5..633ae7becd61 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -919,7 +919,8 @@ static int ext4_xattr_credits_for_new_inode(struct inode *dir, mode_t mode,
  * For other inodes, search forward from the parent directory's block
  * group to find a free inode.
  */
-struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
+struct inode *__ext4_new_inode(struct user_namespace *mnt_userns,
+			       handle_t *handle, struct inode *dir,
 			       umode_t mode, const struct qstr *qstr,
 			       __u32 goal, uid_t *owner, __u32 i_flags,
 			       int handle_type, unsigned int line_no,
@@ -969,10 +970,10 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
 		i_gid_write(inode, owner[1]);
 	} else if (test_opt(sb, GRPID)) {
 		inode->i_mode = mode;
-		inode->i_uid = current_fsuid();
+		inode->i_uid = fsuid_into_mnt(mnt_userns);
 		inode->i_gid = dir->i_gid;
 	} else
-		inode_init_owner(inode, dir, mode);
+		inode_init_owner(mnt_userns, inode, dir, mode);
 
 	if (ext4_has_feature_project(sb) &&
 	    ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT))
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index de7905284e28..650c5acd2f2d 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -20,6 +20,7 @@
  */
 
 #include <linux/fs.h>
+#include <linux/mount.h>
 #include <linux/time.h>
 #include <linux/highuid.h>
 #include <linux/pagemap.h>
@@ -5315,7 +5316,8 @@ static void ext4_wait_for_tail_page_commit(struct inode *inode)
  *
  * Called with inode->i_mutex down.
  */
-int ext4_setattr(struct dentry *dentry, struct iattr *attr)
+int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error, rc = 0;
@@ -5333,7 +5335,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 				  ATTR_GID | ATTR_TIMES_SET))))
 		return -EPERM;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(mnt_userns, dentry, attr);
 	if (error)
 		return error;
 
@@ -5508,7 +5510,7 @@ out_mmap_sem:
 	}
 
 	if (!error) {
-		setattr_copy(inode, attr);
+		setattr_copy(mnt_userns, inode, attr);
 		mark_inode_dirty(inode);
 	}
 
@@ -5520,7 +5522,7 @@ out_mmap_sem:
 		ext4_orphan_del(NULL, inode);
 
 	if (!error && (ia_valid & ATTR_MODE))
-		rc = posix_acl_chmod(inode, inode->i_mode);
+		rc = posix_acl_chmod(mnt_userns, inode, inode->i_mode);
 
 err_out:
 	if  (error)
@@ -5531,8 +5533,8 @@ err_out:
 	return error;
 }
 
-int ext4_getattr(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int query_flags)
+int ext4_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct ext4_inode *raw_inode;
@@ -5567,17 +5569,18 @@ int ext4_getattr(const struct path *path, struct kstat *stat,
 				  STATX_ATTR_NODUMP |
 				  STATX_ATTR_VERITY);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(mnt_userns, inode, stat);
 	return 0;
 }
 
-int ext4_file_getattr(const struct path *path, struct kstat *stat,
+int ext4_file_getattr(struct user_namespace *mnt_userns,
+		      const struct path *path, struct kstat *stat,
 		      u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	u64 delalloc_blocks;
 
-	ext4_getattr(path, stat, request_mask, query_flags);
+	ext4_getattr(mnt_userns, path, stat, request_mask, query_flags);
 
 	/*
 	 * If there is inline data in the inode, the inode will normally not
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 713b1ae44c1a..a2cf35066f46 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -107,10 +107,12 @@ void ext4_reset_inode_seed(struct inode *inode)
  * important fields of the inodes.
  *
  * @sb:         the super block of the filesystem
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode:      the inode to swap with EXT4_BOOT_LOADER_INO
  *
  */
 static long swap_inode_boot_loader(struct super_block *sb,
+				struct user_namespace *mnt_userns,
 				struct inode *inode)
 {
 	handle_t *handle;
@@ -139,7 +141,8 @@ static long swap_inode_boot_loader(struct super_block *sb,
 	}
 
 	if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
-	    !inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) {
+	    !inode_owner_or_capable(mnt_userns, inode) ||
+	    !capable(CAP_SYS_ADMIN)) {
 		err = -EPERM;
 		goto journal_err_out;
 	}
@@ -814,6 +817,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	struct inode *inode = file_inode(filp);
 	struct super_block *sb = inode->i_sb;
 	struct ext4_inode_info *ei = EXT4_I(inode);
+	struct user_namespace *mnt_userns = file_mnt_user_ns(filp);
 	unsigned int flags;
 
 	ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
@@ -829,7 +833,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	case FS_IOC_SETFLAGS: {
 		int err;
 
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EACCES;
 
 		if (get_user(flags, (int __user *) arg))
@@ -871,7 +875,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		__u32 generation;
 		int err;
 
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EPERM;
 
 		if (ext4_has_metadata_csum(inode->i_sb)) {
@@ -1010,7 +1014,7 @@ mext_out:
 	case EXT4_IOC_MIGRATE:
 	{
 		int err;
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EACCES;
 
 		err = mnt_want_write_file(filp);
@@ -1032,7 +1036,7 @@ mext_out:
 	case EXT4_IOC_ALLOC_DA_BLKS:
 	{
 		int err;
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EACCES;
 
 		err = mnt_want_write_file(filp);
@@ -1051,7 +1055,7 @@ mext_out:
 		err = mnt_want_write_file(filp);
 		if (err)
 			return err;
-		err = swap_inode_boot_loader(sb, inode);
+		err = swap_inode_boot_loader(sb, mnt_userns, inode);
 		mnt_drop_write_file(filp);
 		return err;
 	}
@@ -1217,7 +1221,7 @@ resizefs_out:
 
 	case EXT4_IOC_CLEAR_ES_CACHE:
 	{
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EACCES;
 		ext4_clear_inode_es(inode);
 		return 0;
@@ -1263,7 +1267,7 @@ resizefs_out:
 			return -EFAULT;
 
 		/* Make sure caller has proper permission */
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(mnt_userns, inode))
 			return -EACCES;
 
 		if (fa.fsx_xflags & ~EXT4_SUPPORTED_FS_XFLAGS)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index cf652ba3e74d..877c602ae063 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2596,8 +2596,8 @@ static int ext4_add_nondir(handle_t *handle,
  * If the create succeeds, we fill in the inode information
  * with d_instantiate().
  */
-static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		       bool excl)
+static int ext4_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
 	handle_t *handle;
 	struct inode *inode;
@@ -2610,8 +2610,8 @@ static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
 		   EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
 retry:
-	inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
-					    NULL, EXT4_HT_DIR, credits);
+	inode = ext4_new_inode_start_handle(mnt_userns, dir, mode, &dentry->d_name,
+					    0, NULL, EXT4_HT_DIR, credits);
 	handle = ext4_journal_current_handle();
 	err = PTR_ERR(inode);
 	if (!IS_ERR(inode)) {
@@ -2631,8 +2631,8 @@ retry:
 	return err;
 }
 
-static int ext4_mknod(struct inode *dir, struct dentry *dentry,
-		      umode_t mode, dev_t rdev)
+static int ext4_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	handle_t *handle;
 	struct inode *inode;
@@ -2645,8 +2645,8 @@ static int ext4_mknod(struct inode *dir, struct dentry *dentry,
 	credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
 		   EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
 retry:
-	inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
-					    NULL, EXT4_HT_DIR, credits);
+	inode = ext4_new_inode_start_handle(mnt_userns, dir, mode, &dentry->d_name,
+					    0, NULL, EXT4_HT_DIR, credits);
 	handle = ext4_journal_current_handle();
 	err = PTR_ERR(inode);
 	if (!IS_ERR(inode)) {
@@ -2665,7 +2665,8 @@ retry:
 	return err;
 }
 
-static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ext4_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode)
 {
 	handle_t *handle;
 	struct inode *inode;
@@ -2676,7 +2677,7 @@ static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 		return err;
 
 retry:
-	inode = ext4_new_inode_start_handle(dir, mode,
+	inode = ext4_new_inode_start_handle(mnt_userns, dir, mode,
 					    NULL, 0, NULL,
 					    EXT4_HT_DIR,
 			EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
@@ -2774,7 +2775,8 @@ out:
 	return err;
 }
 
-static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ext4_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	handle_t *handle;
 	struct inode *inode;
@@ -2790,7 +2792,7 @@ static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
 		   EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
 retry:
-	inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode,
+	inode = ext4_new_inode_start_handle(mnt_userns, dir, S_IFDIR | mode,
 					    &dentry->d_name,
 					    0, NULL, EXT4_HT_DIR, credits);
 	handle = ext4_journal_current_handle();
@@ -3292,7 +3294,7 @@ out_trace:
 	return retval;
 }
 
-static int ext4_symlink(struct inode *dir,
+static int ext4_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 			struct dentry *dentry, const char *symname)
 {
 	handle_t *handle;
@@ -3333,7 +3335,7 @@ static int ext4_symlink(struct inode *dir,
 			  EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
 	}
 
-	inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO,
+	inode = ext4_new_inode_start_handle(mnt_userns, dir, S_IFLNK|S_IRWXUGO,
 					    &dentry->d_name, 0, NULL,
 					    EXT4_HT_DIR, credits);
 	handle = ext4_journal_current_handle();
@@ -3662,7 +3664,8 @@ static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
 	}
 }
 
-static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
+static struct inode *ext4_whiteout_for_rename(struct user_namespace *mnt_userns,
+					      struct ext4_renament *ent,
 					      int credits, handle_t **h)
 {
 	struct inode *wh;
@@ -3676,7 +3679,8 @@ static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
 	credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
 		    EXT4_XATTR_TRANS_BLOCKS + 4);
 retry:
-	wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE,
+	wh = ext4_new_inode_start_handle(mnt_userns, ent->dir,
+					 S_IFCHR | WHITEOUT_MODE,
 					 &ent->dentry->d_name, 0, NULL,
 					 EXT4_HT_DIR, credits);
 
@@ -3703,9 +3707,9 @@ retry:
  * while new_{dentry,inode) refers to the destination dentry/inode
  * This comes from rename(const char *oldpath, const char *newpath)
  */
-static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
-		       struct inode *new_dir, struct dentry *new_dentry,
-		       unsigned int flags)
+static int ext4_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
 {
 	handle_t *handle = NULL;
 	struct ext4_renament old = {
@@ -3789,7 +3793,7 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
 			goto end_rename;
 		}
 	} else {
-		whiteout = ext4_whiteout_for_rename(&old, credits, &handle);
+		whiteout = ext4_whiteout_for_rename(mnt_userns, &old, credits, &handle);
 		if (IS_ERR(whiteout)) {
 			retval = PTR_ERR(whiteout);
 			whiteout = NULL;
@@ -4085,7 +4089,8 @@ end_rename:
 	return retval;
 }
 
-static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
+static int ext4_rename2(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
 			struct inode *new_dir, struct dentry *new_dentry,
 			unsigned int flags)
 {
@@ -4107,7 +4112,7 @@ static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
 					 new_dir, new_dentry);
 	}
 
-	return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
+	return ext4_rename(mnt_userns, old_dir, old_dentry, new_dir, new_dentry, flags);
 }
 
 /*
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index fb5985102c1d..802bd26ed01c 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -6654,7 +6654,7 @@ static struct file_system_type ext4_fs_type = {
 	.name		= "ext4",
 	.mount		= ext4_mount,
 	.kill_sb	= kill_block_super,
-	.fs_flags	= FS_REQUIRES_DEV,
+	.fs_flags	= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
 };
 MODULE_ALIAS_FS("ext4");
 
diff --git a/fs/ext4/xattr_hurd.c b/fs/ext4/xattr_hurd.c
index 8cfa74a56361..c78df5790377 100644
--- a/fs/ext4/xattr_hurd.c
+++ b/fs/ext4/xattr_hurd.c
@@ -32,6 +32,7 @@ ext4_xattr_hurd_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_hurd_set(const struct xattr_handler *handler,
+		    struct user_namespace *mnt_userns,
 		    struct dentry *unused, struct inode *inode,
 		    const char *name, const void *value,
 		    size_t size, int flags)
diff --git a/fs/ext4/xattr_security.c b/fs/ext4/xattr_security.c
index 197a9d8a15ef..8213f66f7b2d 100644
--- a/fs/ext4/xattr_security.c
+++ b/fs/ext4/xattr_security.c
@@ -23,6 +23,7 @@ ext4_xattr_security_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_security_set(const struct xattr_handler *handler,
+			struct user_namespace *mnt_userns,
 			struct dentry *unused, struct inode *inode,
 			const char *name, const void *value,
 			size_t size, int flags)
diff --git a/fs/ext4/xattr_trusted.c b/fs/ext4/xattr_trusted.c
index e9389e5d75c3..7c21ffb26d25 100644
--- a/fs/ext4/xattr_trusted.c
+++ b/fs/ext4/xattr_trusted.c
@@ -30,6 +30,7 @@ ext4_xattr_trusted_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_trusted_set(const struct xattr_handler *handler,
+		       struct user_namespace *mnt_userns,
 		       struct dentry *unused, struct inode *inode,
 		       const char *name, const void *value,
 		       size_t size, int flags)
diff --git a/fs/ext4/xattr_user.c b/fs/ext4/xattr_user.c
index d4546184b34b..2fe7ff0a479c 100644
--- a/fs/ext4/xattr_user.c
+++ b/fs/ext4/xattr_user.c
@@ -31,6 +31,7 @@ ext4_xattr_user_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_user_set(const struct xattr_handler *handler,
+		    struct user_namespace *mnt_userns,
 		    struct dentry *unused, struct inode *inode,
 		    const char *name, const void *value,
 		    size_t size, int flags)
diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c
index 732ec10e7890..965037a9c205 100644
--- a/fs/f2fs/acl.c
+++ b/fs/f2fs/acl.c
@@ -214,8 +214,8 @@ static int f2fs_acl_update_mode(struct inode *inode, umode_t *mode_p,
 		return error;
 	if (error == 0)
 		*acl = NULL;
-	if (!in_group_p(inode->i_gid) &&
-	    !capable_wrt_inode_uidgid(inode, CAP_FSETID))
+	if (!in_group_p(i_gid_into_mnt(&init_user_ns, inode)) &&
+	    !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
 		mode &= ~S_ISGID;
 	*mode_p = mode;
 	return 0;
@@ -269,7 +269,8 @@ static int __f2fs_set_acl(struct inode *inode, int type,
 	return error;
 }
 
-int f2fs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int f2fs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type)
 {
 	if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
 		return -EIO;
diff --git a/fs/f2fs/acl.h b/fs/f2fs/acl.h
index 124868c13f80..986fd1bc780b 100644
--- a/fs/f2fs/acl.h
+++ b/fs/f2fs/acl.h
@@ -34,7 +34,8 @@ struct f2fs_acl_header {
 #ifdef CONFIG_F2FS_FS_POSIX_ACL
 
 extern struct posix_acl *f2fs_get_acl(struct inode *, int);
-extern int f2fs_set_acl(struct inode *, struct posix_acl *, int);
+extern int f2fs_set_acl(struct user_namespace *, struct inode *,
+			struct posix_acl *, int);
 extern int f2fs_init_acl(struct inode *, struct inode *, struct page *,
 							struct page *);
 #else
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 506c801880f3..e2d302ae3a46 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3187,9 +3187,10 @@ void f2fs_truncate_data_blocks(struct dnode_of_data *dn);
 int f2fs_do_truncate_blocks(struct inode *inode, u64 from, bool lock);
 int f2fs_truncate_blocks(struct inode *inode, u64 from, bool lock);
 int f2fs_truncate(struct inode *inode);
-int f2fs_getattr(const struct path *path, struct kstat *stat,
-			u32 request_mask, unsigned int flags);
-int f2fs_setattr(struct dentry *dentry, struct iattr *attr);
+int f2fs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int flags);
+int f2fs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *attr);
 int f2fs_truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end);
 void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count);
 int f2fs_precache_extents(struct inode *inode);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 471a6ff0c937..d26ff2ae3f5e 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -789,8 +789,8 @@ int f2fs_truncate(struct inode *inode)
 	return 0;
 }
 
-int f2fs_getattr(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int query_flags)
+int f2fs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct f2fs_inode_info *fi = F2FS_I(inode);
@@ -826,7 +826,7 @@ int f2fs_getattr(const struct path *path, struct kstat *stat,
 				  STATX_ATTR_NODUMP |
 				  STATX_ATTR_VERITY);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 
 	/* we need to show initial sectors used for inline_data/dentries */
 	if ((S_ISREG(inode->i_mode) && f2fs_has_inline_data(inode)) ||
@@ -837,7 +837,8 @@ int f2fs_getattr(const struct path *path, struct kstat *stat,
 }
 
 #ifdef CONFIG_F2FS_FS_POSIX_ACL
-static void __setattr_copy(struct inode *inode, const struct iattr *attr)
+static void __setattr_copy(struct user_namespace *mnt_userns,
+			   struct inode *inode, const struct iattr *attr)
 {
 	unsigned int ia_valid = attr->ia_valid;
 
@@ -853,9 +854,9 @@ static void __setattr_copy(struct inode *inode, const struct iattr *attr)
 		inode->i_ctime = attr->ia_ctime;
 	if (ia_valid & ATTR_MODE) {
 		umode_t mode = attr->ia_mode;
+		kgid_t kgid = i_gid_into_mnt(mnt_userns, inode);
 
-		if (!in_group_p(inode->i_gid) &&
-			!capable_wrt_inode_uidgid(inode, CAP_FSETID))
+		if (!in_group_p(kgid) && !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID))
 			mode &= ~S_ISGID;
 		set_acl_inode(inode, mode);
 	}
@@ -864,7 +865,8 @@ static void __setattr_copy(struct inode *inode, const struct iattr *attr)
 #define __setattr_copy setattr_copy
 #endif
 
-int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
+int f2fs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int err;
@@ -884,7 +886,7 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
 		!f2fs_is_compress_backend_ready(inode))
 		return -EOPNOTSUPP;
 
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err)
 		return err;
 
@@ -960,10 +962,10 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
 		spin_unlock(&F2FS_I(inode)->i_size_lock);
 	}
 
-	__setattr_copy(inode, attr);
+	__setattr_copy(&init_user_ns, inode, attr);
 
 	if (attr->ia_valid & ATTR_MODE) {
-		err = posix_acl_chmod(inode, f2fs_get_inode_mode(inode));
+		err = posix_acl_chmod(&init_user_ns, inode, f2fs_get_inode_mode(inode));
 
 		if (is_inode_flag_set(inode, FI_ACL_MODE)) {
 			if (!err)
@@ -1978,7 +1980,7 @@ static int f2fs_ioc_setflags(struct file *filp, unsigned long arg)
 	u32 iflags;
 	int ret;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	if (get_user(fsflags, (int __user *)arg))
@@ -2025,7 +2027,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp)
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 	int ret;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	if (!S_ISREG(inode->i_mode))
@@ -2092,7 +2094,7 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp)
 	struct inode *inode = file_inode(filp);
 	int ret;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	ret = mnt_want_write_file(filp);
@@ -2134,7 +2136,7 @@ static int f2fs_ioc_start_volatile_write(struct file *filp)
 	struct inode *inode = file_inode(filp);
 	int ret;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	if (!S_ISREG(inode->i_mode))
@@ -2169,7 +2171,7 @@ static int f2fs_ioc_release_volatile_write(struct file *filp)
 	struct inode *inode = file_inode(filp);
 	int ret;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	ret = mnt_want_write_file(filp);
@@ -2198,7 +2200,7 @@ static int f2fs_ioc_abort_volatile_write(struct file *filp)
 	struct inode *inode = file_inode(filp);
 	int ret;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	ret = mnt_want_write_file(filp);
@@ -3175,7 +3177,7 @@ static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg)
 		return -EFAULT;
 
 	/* Make sure caller has proper permission */
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	if (fa.fsx_xflags & ~F2FS_SUPPORTED_XFLAGS)
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 887804968576..17bd072a5d39 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -46,7 +46,7 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
 
 	nid_free = true;
 
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 
 	inode->i_ino = ino;
 	inode->i_blocks = 0;
@@ -314,8 +314,8 @@ static void set_compress_inode(struct f2fs_sb_info *sbi, struct inode *inode,
 	}
 }
 
-static int f2fs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-						bool excl)
+static int f2fs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 	struct inode *inode;
@@ -637,8 +637,8 @@ static const char *f2fs_get_link(struct dentry *dentry,
 	return link;
 }
 
-static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
-					const char *symname)
+static int f2fs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, const char *symname)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 	struct inode *inode;
@@ -717,7 +717,8 @@ out_free_encrypted_link:
 	return err;
 }
 
-static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int f2fs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 	struct inode *inode;
@@ -770,8 +771,8 @@ static int f2fs_rmdir(struct inode *dir, struct dentry *dentry)
 	return -ENOTEMPTY;
 }
 
-static int f2fs_mknod(struct inode *dir, struct dentry *dentry,
-				umode_t mode, dev_t rdev)
+static int f2fs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 	struct inode *inode;
@@ -878,7 +879,8 @@ out:
 	return err;
 }
 
-static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int f2fs_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 
@@ -1255,7 +1257,8 @@ out:
 	return err;
 }
 
-static int f2fs_rename2(struct inode *old_dir, struct dentry *old_dentry,
+static int f2fs_rename2(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
 			struct inode *new_dir, struct dentry *new_dentry,
 			unsigned int flags)
 {
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index 8159fae74b9a..490f843ec3bf 100644
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -64,6 +64,7 @@ static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
 }
 
 static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
+		struct user_namespace *mnt_userns,
 		struct dentry *unused, struct inode *inode,
 		const char *name, const void *value,
 		size_t size, int flags)
@@ -107,6 +108,7 @@ static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
 }
 
 static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
+		struct user_namespace *mnt_userns,
 		struct dentry *unused, struct inode *inode,
 		const char *name, const void *value,
 		size_t size, int flags)
@@ -114,7 +116,7 @@ static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
 	unsigned char old_advise = F2FS_I(inode)->i_advise;
 	unsigned char new_advise;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EPERM;
 	if (value == NULL)
 		return -EINVAL;
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index 922a0c6ba46c..02d4d4234956 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -397,9 +397,11 @@ extern long fat_generic_ioctl(struct file *filp, unsigned int cmd,
 			      unsigned long arg);
 extern const struct file_operations fat_file_operations;
 extern const struct inode_operations fat_file_inode_operations;
-extern int fat_setattr(struct dentry *dentry, struct iattr *attr);
+extern int fat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		       struct iattr *attr);
 extern void fat_truncate_blocks(struct inode *inode, loff_t offset);
-extern int fat_getattr(const struct path *path, struct kstat *stat,
+extern int fat_getattr(struct user_namespace *mnt_userns,
+		       const struct path *path, struct kstat *stat,
 		       u32 request_mask, unsigned int flags);
 extern int fat_file_fsync(struct file *file, loff_t start, loff_t end,
 			  int datasync);
diff --git a/fs/fat/file.c b/fs/fat/file.c
index 5fee74f1ad61..13855ba49cd9 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -95,7 +95,7 @@ static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
 		goto out_unlock_inode;
 
 	/* This MUST be done before doing anything irreversible... */
-	err = fat_setattr(file->f_path.dentry, &ia);
+	err = fat_setattr(file_mnt_user_ns(file), file->f_path.dentry, &ia);
 	if (err)
 		goto out_unlock_inode;
 
@@ -394,11 +394,11 @@ void fat_truncate_blocks(struct inode *inode, loff_t offset)
 	fat_flush_inodes(inode->i_sb, inode, NULL);
 }
 
-int fat_getattr(const struct path *path, struct kstat *stat,
-		u32 request_mask, unsigned int flags)
+int fat_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct inode *inode = d_inode(path->dentry);
-	generic_fillattr(inode, stat);
+	generic_fillattr(mnt_userns, inode, stat);
 	stat->blksize = MSDOS_SB(inode->i_sb)->cluster_size;
 
 	if (MSDOS_SB(inode->i_sb)->options.nfs == FAT_NFS_NOSTALE_RO) {
@@ -447,12 +447,13 @@ static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
 	return 0;
 }
 
-static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
+static int fat_allow_set_time(struct user_namespace *mnt_userns,
+			      struct msdos_sb_info *sbi, struct inode *inode)
 {
 	umode_t allow_utime = sbi->options.allow_utime;
 
-	if (!uid_eq(current_fsuid(), inode->i_uid)) {
-		if (in_group_p(inode->i_gid))
+	if (!uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode))) {
+		if (in_group_p(i_gid_into_mnt(mnt_userns, inode)))
 			allow_utime >>= 3;
 		if (allow_utime & MAY_WRITE)
 			return 1;
@@ -466,7 +467,8 @@ static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
 /* valid file mode bits */
 #define FAT_VALID_MODE	(S_IFREG | S_IFDIR | S_IRWXUGO)
 
-int fat_setattr(struct dentry *dentry, struct iattr *attr)
+int fat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		struct iattr *attr)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
 	struct inode *inode = d_inode(dentry);
@@ -476,11 +478,11 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
 	/* Check for setting the inode time. */
 	ia_valid = attr->ia_valid;
 	if (ia_valid & TIMES_SET_FLAGS) {
-		if (fat_allow_set_time(sbi, inode))
+		if (fat_allow_set_time(mnt_userns, sbi, inode))
 			attr->ia_valid &= ~TIMES_SET_FLAGS;
 	}
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(mnt_userns, dentry, attr);
 	attr->ia_valid = ia_valid;
 	if (error) {
 		if (sbi->options.quiet)
@@ -550,7 +552,7 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
 		fat_truncate_time(inode, &attr->ia_mtime, S_MTIME);
 	attr->ia_valid &= ~(ATTR_ATIME|ATTR_CTIME|ATTR_MTIME);
 
-	setattr_copy(inode, attr);
+	setattr_copy(mnt_userns, inode, attr);
 	mark_inode_dirty(inode);
 out:
 	return error;
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 9d062886fbc1..efba301d68ae 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -261,8 +261,8 @@ static int msdos_add_entry(struct inode *dir, const unsigned char *name,
 }
 
 /***** Create a file */
-static int msdos_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-			bool excl)
+static int msdos_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct super_block *sb = dir->i_sb;
 	struct inode *inode = NULL;
@@ -339,7 +339,8 @@ out:
 }
 
 /***** Make a directory */
-static int msdos_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int msdos_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct super_block *sb = dir->i_sb;
 	struct fat_slot_info sinfo;
@@ -593,7 +594,8 @@ error_inode:
 }
 
 /***** Rename, a wrapper for rename_same_dir & rename_diff_dir */
-static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
+static int msdos_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
 			struct inode *new_dir, struct dentry *new_dentry,
 			unsigned int flags)
 {
@@ -665,7 +667,7 @@ static struct file_system_type msdos_fs_type = {
 	.name		= "msdos",
 	.mount		= msdos_mount,
 	.kill_sb	= kill_block_super,
-	.fs_flags	= FS_REQUIRES_DEV,
+	.fs_flags	= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
 };
 MODULE_ALIAS_FS("msdos");
 
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 0cdd0fb9f742..5369d82e0bfb 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -756,8 +756,8 @@ error:
 	return ERR_PTR(err);
 }
 
-static int vfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		       bool excl)
+static int vfat_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct super_block *sb = dir->i_sb;
 	struct inode *inode;
@@ -846,7 +846,8 @@ out:
 	return err;
 }
 
-static int vfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int vfat_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	struct super_block *sb = dir->i_sb;
 	struct inode *inode;
@@ -892,9 +893,9 @@ out:
 	return err;
 }
 
-static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
-		       struct inode *new_dir, struct dentry *new_dentry,
-		       unsigned int flags)
+static int vfat_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
 {
 	struct buffer_head *dotdot_bh;
 	struct msdos_dir_entry *dotdot_de;
@@ -1062,7 +1063,7 @@ static struct file_system_type vfat_fs_type = {
 	.name		= "vfat",
 	.mount		= vfat_mount,
 	.kill_sb	= kill_block_super,
-	.fs_flags	= FS_REQUIRES_DEV,
+	.fs_flags	= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
 };
 MODULE_ALIAS_FS("vfat");
 
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 483ef8861376..dfc72f15be7f 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -25,6 +25,7 @@
 #include <linux/user_namespace.h>
 #include <linux/memfd.h>
 #include <linux/compat.h>
+#include <linux/mount.h>
 
 #include <linux/poll.h>
 #include <asm/siginfo.h>
@@ -46,7 +47,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 
 	/* O_NOATIME can only be set by the owner or superuser */
 	if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(file_mnt_user_ns(filp), inode))
 			return -EPERM;
 
 	/* required for strict SunOS emulation */
diff --git a/fs/fuse/acl.c b/fs/fuse/acl.c
index f529075a2ce8..e9c0f916349d 100644
--- a/fs/fuse/acl.c
+++ b/fs/fuse/acl.c
@@ -50,7 +50,8 @@ struct posix_acl *fuse_get_acl(struct inode *inode, int type)
 	return acl;
 }
 
-int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int fuse_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	const char *name;
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 78f9f209078c..06a18700a845 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -605,7 +605,8 @@ out_err:
 	return err;
 }
 
-static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t);
+static int fuse_mknod(struct user_namespace *, struct inode *, struct dentry *,
+		      umode_t, dev_t);
 static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
 			    struct file *file, unsigned flags,
 			    umode_t mode)
@@ -645,7 +646,7 @@ out_dput:
 	return err;
 
 mknod:
-	err = fuse_mknod(dir, entry, mode, 0);
+	err = fuse_mknod(&init_user_ns, dir, entry, mode, 0);
 	if (err)
 		goto out_dput;
 no_open:
@@ -715,8 +716,8 @@ static int create_new_entry(struct fuse_mount *fm, struct fuse_args *args,
 	return err;
 }
 
-static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode,
-		      dev_t rdev)
+static int fuse_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *entry, umode_t mode, dev_t rdev)
 {
 	struct fuse_mknod_in inarg;
 	struct fuse_mount *fm = get_fuse_mount(dir);
@@ -738,13 +739,14 @@ static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode,
 	return create_new_entry(fm, &args, dir, entry, mode);
 }
 
-static int fuse_create(struct inode *dir, struct dentry *entry, umode_t mode,
-		       bool excl)
+static int fuse_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *entry, umode_t mode, bool excl)
 {
-	return fuse_mknod(dir, entry, mode, 0);
+	return fuse_mknod(&init_user_ns, dir, entry, mode, 0);
 }
 
-static int fuse_mkdir(struct inode *dir, struct dentry *entry, umode_t mode)
+static int fuse_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *entry, umode_t mode)
 {
 	struct fuse_mkdir_in inarg;
 	struct fuse_mount *fm = get_fuse_mount(dir);
@@ -765,8 +767,8 @@ static int fuse_mkdir(struct inode *dir, struct dentry *entry, umode_t mode)
 	return create_new_entry(fm, &args, dir, entry, S_IFDIR);
 }
 
-static int fuse_symlink(struct inode *dir, struct dentry *entry,
-			const char *link)
+static int fuse_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *entry, const char *link)
 {
 	struct fuse_mount *fm = get_fuse_mount(dir);
 	unsigned len = strlen(link) + 1;
@@ -908,9 +910,9 @@ static int fuse_rename_common(struct inode *olddir, struct dentry *oldent,
 	return err;
 }
 
-static int fuse_rename2(struct inode *olddir, struct dentry *oldent,
-			struct inode *newdir, struct dentry *newent,
-			unsigned int flags)
+static int fuse_rename2(struct user_namespace *mnt_userns, struct inode *olddir,
+			struct dentry *oldent, struct inode *newdir,
+			struct dentry *newent, unsigned int flags)
 {
 	struct fuse_conn *fc = get_fuse_conn(olddir);
 	int err;
@@ -1087,7 +1089,7 @@ static int fuse_update_get_attr(struct inode *inode, struct file *file,
 		forget_all_cached_acls(inode);
 		err = fuse_do_getattr(inode, stat, file);
 	} else if (stat) {
-		generic_fillattr(inode, stat);
+		generic_fillattr(&init_user_ns, inode, stat);
 		stat->mode = fi->orig_i_mode;
 		stat->ino = fi->orig_ino;
 	}
@@ -1249,7 +1251,8 @@ static int fuse_perm_getattr(struct inode *inode, int mask)
  * access request is sent.  Execute permission is still checked
  * locally based on file mode.
  */
-static int fuse_permission(struct inode *inode, int mask)
+static int fuse_permission(struct user_namespace *mnt_userns,
+			   struct inode *inode, int mask)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	bool refreshed = false;
@@ -1280,7 +1283,7 @@ static int fuse_permission(struct inode *inode, int mask)
 	}
 
 	if (fc->default_permissions) {
-		err = generic_permission(inode, mask);
+		err = generic_permission(&init_user_ns, inode, mask);
 
 		/* If permission is denied, try to refresh file
 		   attributes.  This is also needed, because the root
@@ -1288,7 +1291,8 @@ static int fuse_permission(struct inode *inode, int mask)
 		if (err == -EACCES && !refreshed) {
 			err = fuse_perm_getattr(inode, mask);
 			if (!err)
-				err = generic_permission(inode, mask);
+				err = generic_permission(&init_user_ns,
+							 inode, mask);
 		}
 
 		/* Note: the opposite of the above test does not
@@ -1610,7 +1614,7 @@ int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
 	if (!fc->default_permissions)
 		attr->ia_valid |= ATTR_FORCE;
 
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err)
 		return err;
 
@@ -1756,7 +1760,8 @@ error:
 	return err;
 }
 
-static int fuse_setattr(struct dentry *entry, struct iattr *attr)
+static int fuse_setattr(struct user_namespace *mnt_userns, struct dentry *entry,
+			struct iattr *attr)
 {
 	struct inode *inode = d_inode(entry);
 	struct fuse_conn *fc = get_fuse_conn(inode);
@@ -1818,7 +1823,8 @@ static int fuse_setattr(struct dentry *entry, struct iattr *attr)
 	return ret;
 }
 
-static int fuse_getattr(const struct path *path, struct kstat *stat,
+static int fuse_getattr(struct user_namespace *mnt_userns,
+			const struct path *path, struct kstat *stat,
 			u32 request_mask, unsigned int flags)
 {
 	struct inode *inode = d_inode(path->dentry);
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 7c4b8cb93f9f..68cca8d4db6e 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -1180,8 +1180,8 @@ extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
 
 struct posix_acl;
 struct posix_acl *fuse_get_acl(struct inode *inode, int type);
-int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
-
+int fuse_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type);
 
 /* readdir.c */
 int fuse_readdir(struct file *file, struct dir_context *ctx);
diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c
index cdea18de94f7..1a7d7ace54e1 100644
--- a/fs/fuse/xattr.c
+++ b/fs/fuse/xattr.c
@@ -188,6 +188,7 @@ static int fuse_xattr_get(const struct xattr_handler *handler,
 }
 
 static int fuse_xattr_set(const struct xattr_handler *handler,
+			  struct user_namespace *mnt_userns,
 			  struct dentry *dentry, struct inode *inode,
 			  const char *name, const void *value, size_t size,
 			  int flags)
@@ -214,6 +215,7 @@ static int no_xattr_get(const struct xattr_handler *handler,
 }
 
 static int no_xattr_set(const struct xattr_handler *handler,
+			struct user_namespace *mnt_userns,
 			struct dentry *dentry, struct inode *nodee,
 			const char *name, const void *value,
 			size_t size, int flags)
diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c
index 2e939f5fe751..9165d70ead07 100644
--- a/fs/gfs2/acl.c
+++ b/fs/gfs2/acl.c
@@ -106,7 +106,8 @@ out:
 	return error;
 }
 
-int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int gfs2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type)
 {
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_holder gh;
@@ -130,7 +131,7 @@ int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 
 	mode = inode->i_mode;
 	if (type == ACL_TYPE_ACCESS && acl) {
-		ret = posix_acl_update_mode(inode, &mode, &acl);
+		ret = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
 		if (ret)
 			goto unlock;
 	}
diff --git a/fs/gfs2/acl.h b/fs/gfs2/acl.h
index 61353a1501c5..eccc6a43326c 100644
--- a/fs/gfs2/acl.h
+++ b/fs/gfs2/acl.h
@@ -13,6 +13,7 @@
 
 extern struct posix_acl *gfs2_get_acl(struct inode *inode, int type);
 extern int __gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type);
-extern int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+extern int gfs2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+			struct posix_acl *acl, int type);
 
 #endif /* __ACL_DOT_H__ */
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 07f49e5e6304..95bbdd4bca78 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -238,7 +238,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask,
 		goto out;
 
 	error = -EACCES;
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		goto out;
 
 	error = 0;
@@ -256,7 +256,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask,
 	    !capable(CAP_LINUX_IMMUTABLE))
 		goto out;
 	if (!IS_IMMUTABLE(inode)) {
-		error = gfs2_permission(inode, MAY_WRITE);
+		error = gfs2_permission(&init_user_ns, inode, MAY_WRITE);
 		if (error)
 			goto out;
 	}
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index c1b77e8d6b1c..cfac2c1e67fa 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -325,7 +325,7 @@ struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
 	}
 
 	if (!is_root) {
-		error = gfs2_permission(dir, MAY_EXEC);
+		error = gfs2_permission(&init_user_ns, dir, MAY_EXEC);
 		if (error)
 			goto out;
 	}
@@ -355,7 +355,8 @@ static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
 {
 	int error;
 
-	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
+	error = gfs2_permission(&init_user_ns, &dip->i_inode,
+				MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 
@@ -843,8 +844,8 @@ fail:
  * Returns: errno
  */
 
-static int gfs2_create(struct inode *dir, struct dentry *dentry,
-		       umode_t mode, bool excl)
+static int gfs2_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
 	return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl);
 }
@@ -951,7 +952,7 @@ static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
 	if (inode->i_nlink == 0)
 		goto out_gunlock;
 
-	error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
+	error = gfs2_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
 	if (error)
 		goto out_gunlock;
 
@@ -1068,7 +1069,8 @@ static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
 	if (IS_APPEND(&dip->i_inode))
 		return -EPERM;
 
-	error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
+	error = gfs2_permission(&init_user_ns, &dip->i_inode,
+				MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 
@@ -1204,8 +1206,8 @@ out_inodes:
  * Returns: errno
  */
 
-static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
-			const char *symname)
+static int gfs2_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, const char *symname)
 {
 	unsigned int size;
 
@@ -1225,7 +1227,8 @@ static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
  * Returns: errno
  */
 
-static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int gfs2_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	unsigned dsize = gfs2_max_stuffed_size(GFS2_I(dir));
 	return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0);
@@ -1240,8 +1243,8 @@ static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
  *
  */
 
-static int gfs2_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
-		      dev_t dev)
+static int gfs2_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t dev)
 {
 	return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0);
 }
@@ -1490,7 +1493,8 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 			}
 		}
 	} else {
-		error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
+		error = gfs2_permission(&init_user_ns, ndir,
+					MAY_WRITE | MAY_EXEC);
 		if (error)
 			goto out_gunlock;
 
@@ -1525,7 +1529,8 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 	/* Check out the dir to be renamed */
 
 	if (dir_rename) {
-		error = gfs2_permission(d_inode(odentry), MAY_WRITE);
+		error = gfs2_permission(&init_user_ns, d_inode(odentry),
+					MAY_WRITE);
 		if (error)
 			goto out_gunlock;
 	}
@@ -1688,12 +1693,14 @@ static int gfs2_exchange(struct inode *odir, struct dentry *odentry,
 		goto out_gunlock;
 
 	if (S_ISDIR(old_mode)) {
-		error = gfs2_permission(odentry->d_inode, MAY_WRITE);
+		error = gfs2_permission(&init_user_ns, odentry->d_inode,
+					MAY_WRITE);
 		if (error)
 			goto out_gunlock;
 	}
 	if (S_ISDIR(new_mode)) {
-		error = gfs2_permission(ndentry->d_inode, MAY_WRITE);
+		error = gfs2_permission(&init_user_ns, ndentry->d_inode,
+					MAY_WRITE);
 		if (error)
 			goto out_gunlock;
 	}
@@ -1747,9 +1754,9 @@ out:
 	return error;
 }
 
-static int gfs2_rename2(struct inode *odir, struct dentry *odentry,
-			struct inode *ndir, struct dentry *ndentry,
-			unsigned int flags)
+static int gfs2_rename2(struct user_namespace *mnt_userns, struct inode *odir,
+			struct dentry *odentry, struct inode *ndir,
+			struct dentry *ndentry, unsigned int flags)
 {
 	flags &= ~RENAME_NOREPLACE;
 
@@ -1833,7 +1840,8 @@ out:
  * Returns: errno
  */
 
-int gfs2_permission(struct inode *inode, int mask)
+int gfs2_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		    int mask)
 {
 	struct gfs2_inode *ip;
 	struct gfs2_holder i_gh;
@@ -1852,7 +1860,7 @@ int gfs2_permission(struct inode *inode, int mask)
 	if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
 		error = -EPERM;
 	else
-		error = generic_permission(inode, mask);
+		error = generic_permission(&init_user_ns, inode, mask);
 	if (gfs2_holder_initialized(&i_gh))
 		gfs2_glock_dq_uninit(&i_gh);
 
@@ -1861,7 +1869,7 @@ int gfs2_permission(struct inode *inode, int mask)
 
 static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
 {
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
@@ -1963,7 +1971,8 @@ out:
  * Returns: errno
  */
 
-static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
+static int gfs2_setattr(struct user_namespace *mnt_userns,
+			struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct gfs2_inode *ip = GFS2_I(inode);
@@ -1982,7 +1991,7 @@ static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 		goto error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		goto error;
 
@@ -1993,7 +2002,8 @@ static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
 	else {
 		error = gfs2_setattr_simple(inode, attr);
 		if (!error && attr->ia_valid & ATTR_MODE)
-			error = posix_acl_chmod(inode, inode->i_mode);
+			error = posix_acl_chmod(&init_user_ns, inode,
+						inode->i_mode);
 	}
 
 error:
@@ -2007,6 +2017,7 @@ out:
 
 /**
  * gfs2_getattr - Read out an inode's attributes
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @path: Object to query
  * @stat: The inode's stats
  * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
@@ -2021,7 +2032,8 @@ out:
  * Returns: errno
  */
 
-static int gfs2_getattr(const struct path *path, struct kstat *stat,
+static int gfs2_getattr(struct user_namespace *mnt_userns,
+			const struct path *path, struct kstat *stat,
 			u32 request_mask, unsigned int flags)
 {
 	struct inode *inode = d_inode(path->dentry);
@@ -2049,7 +2061,7 @@ static int gfs2_getattr(const struct path *path, struct kstat *stat,
 				  STATX_ATTR_IMMUTABLE |
 				  STATX_ATTR_NODUMP);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 
 	if (gfs2_holder_initialized(&gh))
 		gfs2_glock_dq_uninit(&gh);
diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h
index 8073b8d2c7fa..c447bd5b3017 100644
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -99,7 +99,8 @@ extern int gfs2_inode_refresh(struct gfs2_inode *ip);
 
 extern struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
 				  int is_root);
-extern int gfs2_permission(struct inode *inode, int mask);
+extern int gfs2_permission(struct user_namespace *mnt_userns,
+			   struct inode *inode, int mask);
 extern int gfs2_setattr_simple(struct inode *inode, struct iattr *attr);
 extern struct inode *gfs2_lookup_simple(struct inode *dip, const char *name);
 extern void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf);
diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c
index 9d7667bc4292..13969a813410 100644
--- a/fs/gfs2/xattr.c
+++ b/fs/gfs2/xattr.c
@@ -1214,6 +1214,7 @@ int __gfs2_xattr_set(struct inode *inode, const char *name,
 }
 
 static int gfs2_xattr_set(const struct xattr_handler *handler,
+			  struct user_namespace *mnt_userns,
 			  struct dentry *unused, struct inode *inode,
 			  const char *name, const void *value,
 			  size_t size, int flags)
diff --git a/fs/hfs/attr.c b/fs/hfs/attr.c
index 74fa62643136..2bd54efaf416 100644
--- a/fs/hfs/attr.c
+++ b/fs/hfs/attr.c
@@ -121,6 +121,7 @@ static int hfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int hfs_xattr_set(const struct xattr_handler *handler,
+			 struct user_namespace *mnt_userns,
 			 struct dentry *unused, struct inode *inode,
 			 const char *name, const void *value, size_t size,
 			 int flags)
diff --git a/fs/hfs/dir.c b/fs/hfs/dir.c
index 3bf2ae0e467c..527f6e46cbe8 100644
--- a/fs/hfs/dir.c
+++ b/fs/hfs/dir.c
@@ -189,8 +189,8 @@ static int hfs_dir_release(struct inode *inode, struct file *file)
  * a directory and return a corresponding inode, given the inode for
  * the directory and the name (and its length) of the new file.
  */
-static int hfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		      bool excl)
+static int hfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct inode *inode;
 	int res;
@@ -219,7 +219,8 @@ static int hfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
  * in a directory, given the inode for the parent directory and the
  * name (and its length) of the new directory.
  */
-static int hfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int hfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode;
 	int res;
@@ -279,9 +280,9 @@ static int hfs_remove(struct inode *dir, struct dentry *dentry)
  * new file/directory.
  * XXX: how do you handle must_be dir?
  */
-static int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		      struct inode *new_dir, struct dentry *new_dentry,
-		      unsigned int flags)
+static int hfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags)
 {
 	int res;
 
diff --git a/fs/hfs/hfs_fs.h b/fs/hfs/hfs_fs.h
index f71c384064c8..b8eb0322a3e5 100644
--- a/fs/hfs/hfs_fs.h
+++ b/fs/hfs/hfs_fs.h
@@ -204,7 +204,8 @@ extern const struct address_space_operations hfs_btree_aops;
 extern struct inode *hfs_new_inode(struct inode *, const struct qstr *, umode_t);
 extern void hfs_inode_write_fork(struct inode *, struct hfs_extent *, __be32 *, __be32 *);
 extern int hfs_write_inode(struct inode *, struct writeback_control *);
-extern int hfs_inode_setattr(struct dentry *, struct iattr *);
+extern int hfs_inode_setattr(struct user_namespace *, struct dentry *,
+			     struct iattr *);
 extern void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
 			__be32 log_size, __be32 phys_size, u32 clump_size);
 extern struct inode *hfs_iget(struct super_block *, struct hfs_cat_key *, hfs_cat_rec *);
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index f35a37c65e5f..3fc5cb346586 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -602,13 +602,15 @@ static int hfs_file_release(struct inode *inode, struct file *file)
  *     correspond to the same HFS file.
  */
 
-int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
+int hfs_inode_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		      struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
 	int error;
 
-	error = setattr_prepare(dentry, attr); /* basic permission checks */
+	error = setattr_prepare(&init_user_ns, dentry,
+				attr); /* basic permission checks */
 	if (error)
 		return error;
 
@@ -647,7 +649,7 @@ int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
 						  current_time(inode);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/fs/hfsplus/dir.c b/fs/hfsplus/dir.c
index 29a9dcfbe81f..03e6c046faf4 100644
--- a/fs/hfsplus/dir.c
+++ b/fs/hfsplus/dir.c
@@ -434,8 +434,8 @@ out:
 	return res;
 }
 
-static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
-			   const char *symname)
+static int hfsplus_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			   struct dentry *dentry, const char *symname)
 {
 	struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 	struct inode *inode;
@@ -476,8 +476,8 @@ out:
 	return res;
 }
 
-static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
-			 umode_t mode, dev_t rdev)
+static int hfsplus_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 	struct inode *inode;
@@ -517,18 +517,20 @@ out:
 	return res;
 }
 
-static int hfsplus_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-			  bool excl)
+static int hfsplus_create(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode, bool excl)
 {
-	return hfsplus_mknod(dir, dentry, mode, 0);
+	return hfsplus_mknod(&init_user_ns, dir, dentry, mode, 0);
 }
 
-static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int hfsplus_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, umode_t mode)
 {
-	return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
+	return hfsplus_mknod(&init_user_ns, dir, dentry, mode | S_IFDIR, 0);
 }
 
-static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
+static int hfsplus_rename(struct user_namespace *mnt_userns,
+			  struct inode *old_dir, struct dentry *old_dentry,
 			  struct inode *new_dir, struct dentry *new_dentry,
 			  unsigned int flags)
 {
diff --git a/fs/hfsplus/hfsplus_fs.h b/fs/hfsplus/hfsplus_fs.h
index a92de5199ec3..12b20479ed2b 100644
--- a/fs/hfsplus/hfsplus_fs.h
+++ b/fs/hfsplus/hfsplus_fs.h
@@ -488,8 +488,9 @@ void hfsplus_inode_write_fork(struct inode *inode,
 			      struct hfsplus_fork_raw *fork);
 int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd);
 int hfsplus_cat_write_inode(struct inode *inode);
-int hfsplus_getattr(const struct path *path, struct kstat *stat,
-		    u32 request_mask, unsigned int query_flags);
+int hfsplus_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		    struct kstat *stat, u32 request_mask,
+		    unsigned int query_flags);
 int hfsplus_file_fsync(struct file *file, loff_t start, loff_t end,
 		       int datasync);
 
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index ca464328b79c..078c5c8a5156 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -241,12 +241,13 @@ static int hfsplus_file_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static int hfsplus_setattr(struct dentry *dentry, struct iattr *attr)
+static int hfsplus_setattr(struct user_namespace *mnt_userns,
+			   struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -264,14 +265,15 @@ static int hfsplus_setattr(struct dentry *dentry, struct iattr *attr)
 		inode->i_mtime = inode->i_ctime = current_time(inode);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 
 	return 0;
 }
 
-int hfsplus_getattr(const struct path *path, struct kstat *stat,
-		    u32 request_mask, unsigned int query_flags)
+int hfsplus_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		    struct kstat *stat, u32 request_mask,
+		    unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
@@ -286,7 +288,7 @@ int hfsplus_getattr(const struct path *path, struct kstat *stat,
 	stat->attributes_mask |= STATX_ATTR_APPEND | STATX_ATTR_IMMUTABLE |
 				 STATX_ATTR_NODUMP;
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	return 0;
 }
 
@@ -376,7 +378,7 @@ struct inode *hfsplus_new_inode(struct super_block *sb, struct inode *dir,
 		return NULL;
 
 	inode->i_ino = sbi->next_cnid++;
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	set_nlink(inode, 1);
 	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 
diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c
index ce15b9496b77..3edb1926d127 100644
--- a/fs/hfsplus/ioctl.c
+++ b/fs/hfsplus/ioctl.c
@@ -91,7 +91,7 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
 	if (err)
 		goto out;
 
-	if (!inode_owner_or_capable(inode)) {
+	if (!inode_owner_or_capable(&init_user_ns, inode)) {
 		err = -EACCES;
 		goto out_drop_write;
 	}
diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index bb0b27d88e50..4d169c5a2673 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -858,6 +858,7 @@ static int hfsplus_osx_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_osx_setxattr(const struct xattr_handler *handler,
+				struct user_namespace *mnt_userns,
 				struct dentry *unused, struct inode *inode,
 				const char *name, const void *buffer,
 				size_t size, int flags)
diff --git a/fs/hfsplus/xattr_security.c b/fs/hfsplus/xattr_security.c
index cfbe6a3bfb1e..c1c7a16cbf21 100644
--- a/fs/hfsplus/xattr_security.c
+++ b/fs/hfsplus/xattr_security.c
@@ -23,6 +23,7 @@ static int hfsplus_security_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_security_setxattr(const struct xattr_handler *handler,
+				     struct user_namespace *mnt_userns,
 				     struct dentry *unused, struct inode *inode,
 				     const char *name, const void *buffer,
 				     size_t size, int flags)
diff --git a/fs/hfsplus/xattr_trusted.c b/fs/hfsplus/xattr_trusted.c
index fbad91e1dada..e150372ec564 100644
--- a/fs/hfsplus/xattr_trusted.c
+++ b/fs/hfsplus/xattr_trusted.c
@@ -22,6 +22,7 @@ static int hfsplus_trusted_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_trusted_setxattr(const struct xattr_handler *handler,
+				    struct user_namespace *mnt_userns,
 				    struct dentry *unused, struct inode *inode,
 				    const char *name, const void *buffer,
 				    size_t size, int flags)
diff --git a/fs/hfsplus/xattr_user.c b/fs/hfsplus/xattr_user.c
index 74d19faf255e..a6b60b153916 100644
--- a/fs/hfsplus/xattr_user.c
+++ b/fs/hfsplus/xattr_user.c
@@ -22,6 +22,7 @@ static int hfsplus_user_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_user_setxattr(const struct xattr_handler *handler,
+				 struct user_namespace *mnt_userns,
 				 struct dentry *unused, struct inode *inode,
 				 const char *name, const void *buffer,
 				 size_t size, int flags)
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 4a5beca6eaa8..29e407762626 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -557,8 +557,8 @@ static int read_name(struct inode *ino, char *name)
 	return 0;
 }
 
-static int hostfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-			 bool excl)
+static int hostfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct inode *inode;
 	char *name;
@@ -656,8 +656,8 @@ static int hostfs_unlink(struct inode *ino, struct dentry *dentry)
 	return err;
 }
 
-static int hostfs_symlink(struct inode *ino, struct dentry *dentry,
-			  const char *to)
+static int hostfs_symlink(struct user_namespace *mnt_userns, struct inode *ino,
+			  struct dentry *dentry, const char *to)
 {
 	char *file;
 	int err;
@@ -669,7 +669,8 @@ static int hostfs_symlink(struct inode *ino, struct dentry *dentry,
 	return err;
 }
 
-static int hostfs_mkdir(struct inode *ino, struct dentry *dentry, umode_t mode)
+static int hostfs_mkdir(struct user_namespace *mnt_userns, struct inode *ino,
+			struct dentry *dentry, umode_t mode)
 {
 	char *file;
 	int err;
@@ -693,7 +694,8 @@ static int hostfs_rmdir(struct inode *ino, struct dentry *dentry)
 	return err;
 }
 
-static int hostfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+static int hostfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, dev_t dev)
 {
 	struct inode *inode;
 	char *name;
@@ -731,7 +733,8 @@ static int hostfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 	return err;
 }
 
-static int hostfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
+static int hostfs_rename2(struct user_namespace *mnt_userns,
+			  struct inode *old_dir, struct dentry *old_dentry,
 			  struct inode *new_dir, struct dentry *new_dentry,
 			  unsigned int flags)
 {
@@ -759,7 +762,8 @@ static int hostfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
 	return err;
 }
 
-static int hostfs_permission(struct inode *ino, int desired)
+static int hostfs_permission(struct user_namespace *mnt_userns,
+			     struct inode *ino, int desired)
 {
 	char *name;
 	int r = 0, w = 0, x = 0, err;
@@ -781,11 +785,12 @@ static int hostfs_permission(struct inode *ino, int desired)
 		err = access_file(name, r, w, x);
 	__putname(name);
 	if (!err)
-		err = generic_permission(ino, desired);
+		err = generic_permission(&init_user_ns, ino, desired);
 	return err;
 }
 
-static int hostfs_setattr(struct dentry *dentry, struct iattr *attr)
+static int hostfs_setattr(struct user_namespace *mnt_userns,
+			  struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct hostfs_iattr attrs;
@@ -794,7 +799,7 @@ static int hostfs_setattr(struct dentry *dentry, struct iattr *attr)
 
 	int fd = HOSTFS_I(inode)->fd;
 
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err)
 		return err;
 
@@ -851,7 +856,7 @@ static int hostfs_setattr(struct dentry *dentry, struct iattr *attr)
 	    attr->ia_size != i_size_read(inode))
 		truncate_setsize(inode, attr->ia_size);
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/fs/hpfs/hpfs_fn.h b/fs/hpfs/hpfs_fn.h
index 1cca83218fb5..167ec6884642 100644
--- a/fs/hpfs/hpfs_fn.h
+++ b/fs/hpfs/hpfs_fn.h
@@ -280,7 +280,7 @@ void hpfs_init_inode(struct inode *);
 void hpfs_read_inode(struct inode *);
 void hpfs_write_inode(struct inode *);
 void hpfs_write_inode_nolock(struct inode *);
-int hpfs_setattr(struct dentry *, struct iattr *);
+int hpfs_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 void hpfs_write_if_changed(struct inode *);
 void hpfs_evict_inode(struct inode *);
 
diff --git a/fs/hpfs/inode.c b/fs/hpfs/inode.c
index eb8b4baf0f2e..82208cc28ebd 100644
--- a/fs/hpfs/inode.c
+++ b/fs/hpfs/inode.c
@@ -257,7 +257,8 @@ void hpfs_write_inode_nolock(struct inode *i)
 	brelse(bh);
 }
 
-int hpfs_setattr(struct dentry *dentry, struct iattr *attr)
+int hpfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error = -EINVAL;
@@ -274,7 +275,7 @@ int hpfs_setattr(struct dentry *dentry, struct iattr *attr)
 	if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > inode->i_size)
 		goto out_unlock;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		goto out_unlock;
 
@@ -288,7 +289,7 @@ int hpfs_setattr(struct dentry *dentry, struct iattr *attr)
 		hpfs_truncate(inode);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 
 	hpfs_write_inode(inode);
 
diff --git a/fs/hpfs/namei.c b/fs/hpfs/namei.c
index 1aee39160ac5..d73f8a67168e 100644
--- a/fs/hpfs/namei.c
+++ b/fs/hpfs/namei.c
@@ -20,7 +20,8 @@ static void hpfs_update_directory_times(struct inode *dir)
 	hpfs_write_inode_nolock(dir);
 }
 
-static int hpfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int hpfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	const unsigned char *name = dentry->d_name.name;
 	unsigned len = dentry->d_name.len;
@@ -128,7 +129,8 @@ bail:
 	return err;
 }
 
-static int hpfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
+static int hpfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
 	const unsigned char *name = dentry->d_name.name;
 	unsigned len = dentry->d_name.len;
@@ -215,7 +217,8 @@ bail:
 	return err;
 }
 
-static int hpfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
+static int hpfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	const unsigned char *name = dentry->d_name.name;
 	unsigned len = dentry->d_name.len;
@@ -289,7 +292,8 @@ bail:
 	return err;
 }
 
-static int hpfs_symlink(struct inode *dir, struct dentry *dentry, const char *symlink)
+static int hpfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, const char *symlink)
 {
 	const unsigned char *name = dentry->d_name.name;
 	unsigned len = dentry->d_name.len;
@@ -506,10 +510,10 @@ fail:
 const struct address_space_operations hpfs_symlink_aops = {
 	.readpage	= hpfs_symlink_readpage
 };
-	
-static int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		       struct inode *new_dir, struct dentry *new_dentry,
-		       unsigned int flags)
+
+static int hpfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
 {
 	const unsigned char *old_name = old_dentry->d_name.name;
 	unsigned old_len = old_dentry->d_name.len;
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 21c20fd5f9ee..b7a72f577aab 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -752,7 +752,8 @@ out:
 	return error;
 }
 
-static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
+static int hugetlbfs_setattr(struct user_namespace *mnt_userns,
+			     struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct hstate *h = hstate_inode(inode);
@@ -762,7 +763,7 @@ static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
 
 	BUG_ON(!inode);
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -781,7 +782,7 @@ static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
 			return error;
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
@@ -837,7 +838,7 @@ static struct inode *hugetlbfs_get_inode(struct super_block *sb,
 		struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
 
 		inode->i_ino = get_next_ino();
-		inode_init_owner(inode, dir, mode);
+		inode_init_owner(&init_user_ns, inode, dir, mode);
 		lockdep_set_class(&inode->i_mapping->i_mmap_rwsem,
 				&hugetlbfs_i_mmap_rwsem_key);
 		inode->i_mapping->a_ops = &hugetlbfs_aops;
@@ -899,33 +900,39 @@ static int do_hugetlbfs_mknod(struct inode *dir,
 	return error;
 }
 
-static int hugetlbfs_mknod(struct inode *dir,
-			struct dentry *dentry, umode_t mode, dev_t dev)
+static int hugetlbfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+			   struct dentry *dentry, umode_t mode, dev_t dev)
 {
 	return do_hugetlbfs_mknod(dir, dentry, mode, dev, false);
 }
 
-static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int hugetlbfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			   struct dentry *dentry, umode_t mode)
 {
-	int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0);
+	int retval = hugetlbfs_mknod(&init_user_ns, dir, dentry,
+				     mode | S_IFDIR, 0);
 	if (!retval)
 		inc_nlink(dir);
 	return retval;
 }
 
-static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
+static int hugetlbfs_create(struct user_namespace *mnt_userns,
+			    struct inode *dir, struct dentry *dentry,
+			    umode_t mode, bool excl)
 {
-	return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0);
+	return hugetlbfs_mknod(&init_user_ns, dir, dentry, mode | S_IFREG, 0);
 }
 
-static int hugetlbfs_tmpfile(struct inode *dir,
-			struct dentry *dentry, umode_t mode)
+static int hugetlbfs_tmpfile(struct user_namespace *mnt_userns,
+			     struct inode *dir, struct dentry *dentry,
+			     umode_t mode)
 {
 	return do_hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0, true);
 }
 
-static int hugetlbfs_symlink(struct inode *dir,
-			struct dentry *dentry, const char *symname)
+static int hugetlbfs_symlink(struct user_namespace *mnt_userns,
+			     struct inode *dir, struct dentry *dentry,
+			     const char *symname)
 {
 	struct inode *inode;
 	int error = -ENOSPC;
diff --git a/fs/init.c b/fs/init.c
index e9c320a48cf1..5c36adaa9b44 100644
--- a/fs/init.c
+++ b/fs/init.c
@@ -49,7 +49,7 @@ int __init init_chdir(const char *filename)
 	error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
 	if (error)
 		return error;
-	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	error = path_permission(&path, MAY_EXEC | MAY_CHDIR);
 	if (!error)
 		set_fs_pwd(current->fs, &path);
 	path_put(&path);
@@ -64,7 +64,7 @@ int __init init_chroot(const char *filename)
 	error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
 	if (error)
 		return error;
-	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	error = path_permission(&path, MAY_EXEC | MAY_CHDIR);
 	if (error)
 		goto dput_and_out;
 	error = -EPERM;
@@ -118,7 +118,7 @@ int __init init_eaccess(const char *filename)
 	error = kern_path(filename, LOOKUP_FOLLOW, &path);
 	if (error)
 		return error;
-	error = inode_permission(d_inode(path.dentry), MAY_ACCESS);
+	error = path_permission(&path, MAY_ACCESS);
 	path_put(&path);
 	return error;
 }
@@ -157,8 +157,8 @@ int __init init_mknod(const char *filename, umode_t mode, unsigned int dev)
 		mode &= ~current_umask();
 	error = security_path_mknod(&path, dentry, mode, dev);
 	if (!error)
-		error = vfs_mknod(path.dentry->d_inode, dentry, mode,
-				  new_decode_dev(dev));
+		error = vfs_mknod(mnt_user_ns(path.mnt), path.dentry->d_inode,
+				  dentry, mode, new_decode_dev(dev));
 	done_path_create(&path, dentry);
 	return error;
 }
@@ -167,6 +167,7 @@ int __init init_link(const char *oldname, const char *newname)
 {
 	struct dentry *new_dentry;
 	struct path old_path, new_path;
+	struct user_namespace *mnt_userns;
 	int error;
 
 	error = kern_path(oldname, 0, &old_path);
@@ -181,14 +182,15 @@ int __init init_link(const char *oldname, const char *newname)
 	error = -EXDEV;
 	if (old_path.mnt != new_path.mnt)
 		goto out_dput;
-	error = may_linkat(&old_path);
+	mnt_userns = mnt_user_ns(new_path.mnt);
+	error = may_linkat(mnt_userns, &old_path);
 	if (unlikely(error))
 		goto out_dput;
 	error = security_path_link(old_path.dentry, &new_path, new_dentry);
 	if (error)
 		goto out_dput;
-	error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry,
-			 NULL);
+	error = vfs_link(old_path.dentry, mnt_userns, new_path.dentry->d_inode,
+			 new_dentry, NULL);
 out_dput:
 	done_path_create(&new_path, new_dentry);
 out:
@@ -207,7 +209,8 @@ int __init init_symlink(const char *oldname, const char *newname)
 		return PTR_ERR(dentry);
 	error = security_path_symlink(&path, dentry, oldname);
 	if (!error)
-		error = vfs_symlink(path.dentry->d_inode, dentry, oldname);
+		error = vfs_symlink(mnt_user_ns(path.mnt), path.dentry->d_inode,
+				    dentry, oldname);
 	done_path_create(&path, dentry);
 	return error;
 }
@@ -230,7 +233,8 @@ int __init init_mkdir(const char *pathname, umode_t mode)
 		mode &= ~current_umask();
 	error = security_path_mkdir(&path, dentry, mode);
 	if (!error)
-		error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
+		error = vfs_mkdir(mnt_user_ns(path.mnt), path.dentry->d_inode,
+				  dentry, mode);
 	done_path_create(&path, dentry);
 	return error;
 }
diff --git a/fs/inode.c b/fs/inode.c
index 874242169547..6dba963d3f6d 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1798,7 +1798,7 @@ bool atime_needs_update(const struct path *path, struct inode *inode)
 	/* Atime updates will likely cause i_uid and i_gid to be written
 	 * back improprely if their true value is unknown to the vfs.
 	 */
-	if (HAS_UNMAPPED_ID(inode))
+	if (HAS_UNMAPPED_ID(mnt_user_ns(mnt), inode))
 		return false;
 
 	if (IS_NOATIME(inode))
@@ -1905,7 +1905,8 @@ int dentry_needs_remove_privs(struct dentry *dentry)
 	return mask;
 }
 
-static int __remove_privs(struct dentry *dentry, int kill)
+static int __remove_privs(struct user_namespace *mnt_userns,
+			  struct dentry *dentry, int kill)
 {
 	struct iattr newattrs;
 
@@ -1914,7 +1915,7 @@ static int __remove_privs(struct dentry *dentry, int kill)
 	 * Note we call this on write, so notify_change will not
 	 * encounter any conflicting delegations:
 	 */
-	return notify_change(dentry, &newattrs, NULL);
+	return notify_change(mnt_userns, dentry, &newattrs, NULL);
 }
 
 /*
@@ -1941,7 +1942,7 @@ int file_remove_privs(struct file *file)
 	if (kill < 0)
 		return kill;
 	if (kill)
-		error = __remove_privs(dentry, kill);
+		error = __remove_privs(file_mnt_user_ns(file), dentry, kill);
 	if (!error)
 		inode_has_no_xattr(inode);
 
@@ -2132,14 +2133,21 @@ EXPORT_SYMBOL(init_special_inode);
 
 /**
  * inode_init_owner - Init uid,gid,mode for new inode according to posix standards
+ * @mnt_userns:	User namespace of the mount the inode was created from
  * @inode: New inode
  * @dir: Directory inode
  * @mode: mode of the new inode
+ *
+ * If the inode has been created through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions
+ * and initializing i_uid and i_gid. On non-idmapped mounts or if permission
+ * checking is to be performed on the raw inode simply passs init_user_ns.
  */
-void inode_init_owner(struct inode *inode, const struct inode *dir,
-			umode_t mode)
+void inode_init_owner(struct user_namespace *mnt_userns, struct inode *inode,
+		      const struct inode *dir, umode_t mode)
 {
-	inode->i_uid = current_fsuid();
+	inode->i_uid = fsuid_into_mnt(mnt_userns);
 	if (dir && dir->i_mode & S_ISGID) {
 		inode->i_gid = dir->i_gid;
 
@@ -2147,31 +2155,41 @@ void inode_init_owner(struct inode *inode, const struct inode *dir,
 		if (S_ISDIR(mode))
 			mode |= S_ISGID;
 		else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) &&
-			 !in_group_p(inode->i_gid) &&
-			 !capable_wrt_inode_uidgid(dir, CAP_FSETID))
+			 !in_group_p(i_gid_into_mnt(mnt_userns, dir)) &&
+			 !capable_wrt_inode_uidgid(mnt_userns, dir, CAP_FSETID))
 			mode &= ~S_ISGID;
 	} else
-		inode->i_gid = current_fsgid();
+		inode->i_gid = fsgid_into_mnt(mnt_userns);
 	inode->i_mode = mode;
 }
 EXPORT_SYMBOL(inode_init_owner);
 
 /**
  * inode_owner_or_capable - check current task permissions to inode
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode: inode being checked
  *
  * Return true if current either has CAP_FOWNER in a namespace with the
  * inode owner uid mapped, or owns the file.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
  */
-bool inode_owner_or_capable(const struct inode *inode)
+bool inode_owner_or_capable(struct user_namespace *mnt_userns,
+			    const struct inode *inode)
 {
+	kuid_t i_uid;
 	struct user_namespace *ns;
 
-	if (uid_eq(current_fsuid(), inode->i_uid))
+	i_uid = i_uid_into_mnt(mnt_userns, inode);
+	if (uid_eq(current_fsuid(), i_uid))
 		return true;
 
 	ns = current_user_ns();
-	if (kuid_has_mapping(ns, inode->i_uid) && ns_capable(ns, CAP_FOWNER))
+	if (kuid_has_mapping(ns, i_uid) && ns_capable(ns, CAP_FOWNER))
 		return true;
 	return false;
 }
diff --git a/fs/internal.h b/fs/internal.h
index 49bfb3750b22..6aeae7ef3380 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -74,7 +74,7 @@ extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
 			   const char *, unsigned int, struct path *);
 long do_rmdir(int dfd, struct filename *name);
 long do_unlinkat(int dfd, struct filename *name);
-int may_linkat(struct path *link);
+int may_linkat(struct user_namespace *mnt_userns, struct path *link);
 int do_renameat2(int olddfd, struct filename *oldname, int newdfd,
 		 struct filename *newname, unsigned int flags);
 
diff --git a/fs/jffs2/acl.c b/fs/jffs2/acl.c
index 093ffbd82395..55a79df70d24 100644
--- a/fs/jffs2/acl.c
+++ b/fs/jffs2/acl.c
@@ -226,7 +226,8 @@ static int __jffs2_set_acl(struct inode *inode, int xprefix, struct posix_acl *a
 	return rc;
 }
 
-int jffs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int jffs2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		  struct posix_acl *acl, int type)
 {
 	int rc, xprefix;
 
@@ -236,7 +237,8 @@ int jffs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 		if (acl) {
 			umode_t mode;
 
-			rc = posix_acl_update_mode(inode, &mode, &acl);
+			rc = posix_acl_update_mode(&init_user_ns, inode, &mode,
+						   &acl);
 			if (rc)
 				return rc;
 			if (inode->i_mode != mode) {
diff --git a/fs/jffs2/acl.h b/fs/jffs2/acl.h
index 12d0271bdde3..62c50da9d493 100644
--- a/fs/jffs2/acl.h
+++ b/fs/jffs2/acl.h
@@ -28,7 +28,8 @@ struct jffs2_acl_header {
 #ifdef CONFIG_JFFS2_FS_POSIX_ACL
 
 struct posix_acl *jffs2_get_acl(struct inode *inode, int type);
-int jffs2_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+int jffs2_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		  struct posix_acl *acl, int type);
 extern int jffs2_init_acl_pre(struct inode *, struct inode *, umode_t *);
 extern int jffs2_init_acl_post(struct inode *);
 
diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c
index 776493713153..c0aabbcbfd58 100644
--- a/fs/jffs2/dir.c
+++ b/fs/jffs2/dir.c
@@ -24,18 +24,21 @@
 
 static int jffs2_readdir (struct file *, struct dir_context *);
 
-static int jffs2_create (struct inode *,struct dentry *,umode_t,
-			 bool);
+static int jffs2_create (struct user_namespace *, struct inode *,
+		         struct dentry *, umode_t, bool);
 static struct dentry *jffs2_lookup (struct inode *,struct dentry *,
 				    unsigned int);
 static int jffs2_link (struct dentry *,struct inode *,struct dentry *);
 static int jffs2_unlink (struct inode *,struct dentry *);
-static int jffs2_symlink (struct inode *,struct dentry *,const char *);
-static int jffs2_mkdir (struct inode *,struct dentry *,umode_t);
+static int jffs2_symlink (struct user_namespace *, struct inode *,
+			  struct dentry *, const char *);
+static int jffs2_mkdir (struct user_namespace *, struct inode *,struct dentry *,
+			umode_t);
 static int jffs2_rmdir (struct inode *,struct dentry *);
-static int jffs2_mknod (struct inode *,struct dentry *,umode_t,dev_t);
-static int jffs2_rename (struct inode *, struct dentry *,
-			 struct inode *, struct dentry *,
+static int jffs2_mknod (struct user_namespace *, struct inode *,struct dentry *,
+			umode_t,dev_t);
+static int jffs2_rename (struct user_namespace *, struct inode *,
+			 struct dentry *, struct inode *, struct dentry *,
 			 unsigned int);
 
 const struct file_operations jffs2_dir_operations =
@@ -157,8 +160,8 @@ static int jffs2_readdir(struct file *file, struct dir_context *ctx)
 /***********************************************************************/
 
 
-static int jffs2_create(struct inode *dir_i, struct dentry *dentry,
-			umode_t mode, bool excl)
+static int jffs2_create(struct user_namespace *mnt_userns, struct inode *dir_i,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct jffs2_raw_inode *ri;
 	struct jffs2_inode_info *f, *dir_f;
@@ -276,7 +279,8 @@ static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct de
 
 /***********************************************************************/
 
-static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char *target)
+static int jffs2_symlink (struct user_namespace *mnt_userns, struct inode *dir_i,
+			  struct dentry *dentry, const char *target)
 {
 	struct jffs2_inode_info *f, *dir_f;
 	struct jffs2_sb_info *c;
@@ -438,7 +442,8 @@ static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char
 }
 
 
-static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, umode_t mode)
+static int jffs2_mkdir (struct user_namespace *mnt_userns, struct inode *dir_i,
+		        struct dentry *dentry, umode_t mode)
 {
 	struct jffs2_inode_info *f, *dir_f;
 	struct jffs2_sb_info *c;
@@ -609,7 +614,8 @@ static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
 	return ret;
 }
 
-static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode, dev_t rdev)
+static int jffs2_mknod (struct user_namespace *mnt_userns, struct inode *dir_i,
+		        struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct jffs2_inode_info *f, *dir_f;
 	struct jffs2_sb_info *c;
@@ -756,7 +762,8 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode
 	return ret;
 }
 
-static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
+static int jffs2_rename (struct user_namespace *mnt_userns,
+			 struct inode *old_dir_i, struct dentry *old_dentry,
 			 struct inode *new_dir_i, struct dentry *new_dentry,
 			 unsigned int flags)
 {
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 78858f6e9583..2ac410477c4f 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -190,18 +190,19 @@ int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
 	return 0;
 }
 
-int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
+int jffs2_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *iattr)
 {
 	struct inode *inode = d_inode(dentry);
 	int rc;
 
-	rc = setattr_prepare(dentry, iattr);
+	rc = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (rc)
 		return rc;
 
 	rc = jffs2_do_setattr(inode, iattr);
 	if (!rc && (iattr->ia_valid & ATTR_MODE))
-		rc = posix_acl_chmod(inode, inode->i_mode);
+		rc = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
 
 	return rc;
 }
diff --git a/fs/jffs2/os-linux.h b/fs/jffs2/os-linux.h
index ef1cfa61549e..173eccac691d 100644
--- a/fs/jffs2/os-linux.h
+++ b/fs/jffs2/os-linux.h
@@ -164,7 +164,7 @@ long jffs2_ioctl(struct file *, unsigned int, unsigned long);
 extern const struct inode_operations jffs2_symlink_inode_operations;
 
 /* fs.c */
-int jffs2_setattr (struct dentry *, struct iattr *);
+int jffs2_setattr (struct user_namespace *, struct dentry *, struct iattr *);
 int jffs2_do_setattr (struct inode *, struct iattr *);
 struct inode *jffs2_iget(struct super_block *, unsigned long);
 void jffs2_evict_inode (struct inode *);
diff --git a/fs/jffs2/security.c b/fs/jffs2/security.c
index c2332e30f218..aef5522551db 100644
--- a/fs/jffs2/security.c
+++ b/fs/jffs2/security.c
@@ -57,6 +57,7 @@ static int jffs2_security_getxattr(const struct xattr_handler *handler,
 }
 
 static int jffs2_security_setxattr(const struct xattr_handler *handler,
+				   struct user_namespace *mnt_userns,
 				   struct dentry *unused, struct inode *inode,
 				   const char *name, const void *buffer,
 				   size_t size, int flags)
diff --git a/fs/jffs2/xattr_trusted.c b/fs/jffs2/xattr_trusted.c
index 5d6030826c52..cc3f24883e7d 100644
--- a/fs/jffs2/xattr_trusted.c
+++ b/fs/jffs2/xattr_trusted.c
@@ -25,6 +25,7 @@ static int jffs2_trusted_getxattr(const struct xattr_handler *handler,
 }
 
 static int jffs2_trusted_setxattr(const struct xattr_handler *handler,
+				  struct user_namespace *mnt_userns,
 				  struct dentry *unused, struct inode *inode,
 				  const char *name, const void *buffer,
 				  size_t size, int flags)
diff --git a/fs/jffs2/xattr_user.c b/fs/jffs2/xattr_user.c
index 9d027b4abcf9..fb945977c013 100644
--- a/fs/jffs2/xattr_user.c
+++ b/fs/jffs2/xattr_user.c
@@ -25,6 +25,7 @@ static int jffs2_user_getxattr(const struct xattr_handler *handler,
 }
 
 static int jffs2_user_setxattr(const struct xattr_handler *handler,
+			       struct user_namespace *mnt_userns,
 			       struct dentry *unused, struct inode *inode,
 			       const char *name, const void *buffer,
 			       size_t size, int flags)
diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c
index 92cc0ac2d1fc..43c285c3d2a7 100644
--- a/fs/jfs/acl.c
+++ b/fs/jfs/acl.c
@@ -91,7 +91,8 @@ out:
 	return rc;
 }
 
-int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int jfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		struct posix_acl *acl, int type)
 {
 	int rc;
 	tid_t tid;
@@ -101,7 +102,7 @@ int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 	tid = txBegin(inode->i_sb, 0);
 	mutex_lock(&JFS_IP(inode)->commit_mutex);
 	if (type == ACL_TYPE_ACCESS && acl) {
-		rc = posix_acl_update_mode(inode, &mode, &acl);
+		rc = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
 		if (rc)
 			goto end_tx;
 		if (mode != inode->i_mode)
diff --git a/fs/jfs/file.c b/fs/jfs/file.c
index 930d2701f206..28b70e7c7dd4 100644
--- a/fs/jfs/file.c
+++ b/fs/jfs/file.c
@@ -85,12 +85,13 @@ static int jfs_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
+int jfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		struct iattr *iattr)
 {
 	struct inode *inode = d_inode(dentry);
 	int rc;
 
-	rc = setattr_prepare(dentry, iattr);
+	rc = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (rc)
 		return rc;
 
@@ -118,11 +119,11 @@ int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 		jfs_truncate(inode);
 	}
 
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 	mark_inode_dirty(inode);
 
 	if (iattr->ia_valid & ATTR_MODE)
-		rc = posix_acl_chmod(inode, inode->i_mode);
+		rc = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
 	return rc;
 }
 
diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
index 10ee0ecca1a8..2581d4db58ff 100644
--- a/fs/jfs/ioctl.c
+++ b/fs/jfs/ioctl.c
@@ -76,7 +76,7 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		if (err)
 			return err;
 
-		if (!inode_owner_or_capable(inode)) {
+		if (!inode_owner_or_capable(&init_user_ns, inode)) {
 			err = -EACCES;
 			goto setflags_out;
 		}
diff --git a/fs/jfs/jfs_acl.h b/fs/jfs/jfs_acl.h
index 9f8f92dd6f84..7ae389a7a366 100644
--- a/fs/jfs/jfs_acl.h
+++ b/fs/jfs/jfs_acl.h
@@ -8,7 +8,8 @@
 #ifdef CONFIG_JFS_POSIX_ACL
 
 struct posix_acl *jfs_get_acl(struct inode *inode, int type);
-int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+int jfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		struct posix_acl *acl, int type);
 int jfs_init_acl(tid_t, struct inode *, struct inode *);
 
 #else
diff --git a/fs/jfs/jfs_inode.c b/fs/jfs/jfs_inode.c
index 4cef170630db..59379089e939 100644
--- a/fs/jfs/jfs_inode.c
+++ b/fs/jfs/jfs_inode.c
@@ -64,7 +64,7 @@ struct inode *ialloc(struct inode *parent, umode_t mode)
 		goto fail_put;
 	}
 
-	inode_init_owner(inode, parent, mode);
+	inode_init_owner(&init_user_ns, inode, parent, mode);
 	/*
 	 * New inodes need to save sane values on disk when
 	 * uid & gid mount options are used
diff --git a/fs/jfs/jfs_inode.h b/fs/jfs/jfs_inode.h
index 70a0d12e427e..01daa0cb0ae5 100644
--- a/fs/jfs/jfs_inode.h
+++ b/fs/jfs/jfs_inode.h
@@ -26,7 +26,7 @@ extern struct dentry *jfs_fh_to_parent(struct super_block *sb, struct fid *fid,
 	int fh_len, int fh_type);
 extern void jfs_set_inode_flags(struct inode *);
 extern int jfs_get_block(struct inode *, sector_t, struct buffer_head *, int);
-extern int jfs_setattr(struct dentry *, struct iattr *);
+extern int jfs_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 
 extern const struct address_space_operations jfs_aops;
 extern const struct inode_operations jfs_dir_inode_operations;
diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
index 7a55d14cc1af..9abed0d750e5 100644
--- a/fs/jfs/namei.c
+++ b/fs/jfs/namei.c
@@ -59,8 +59,8 @@ static inline void free_ea_wmap(struct inode *inode)
  * RETURN:	Errors from subroutines
  *
  */
-static int jfs_create(struct inode *dip, struct dentry *dentry, umode_t mode,
-		bool excl)
+static int jfs_create(struct user_namespace *mnt_userns, struct inode *dip,
+		      struct dentry *dentry, umode_t mode, bool excl)
 {
 	int rc = 0;
 	tid_t tid;		/* transaction id */
@@ -192,7 +192,8 @@ static int jfs_create(struct inode *dip, struct dentry *dentry, umode_t mode,
  * note:
  * EACCES: user needs search+write permission on the parent directory
  */
-static int jfs_mkdir(struct inode *dip, struct dentry *dentry, umode_t mode)
+static int jfs_mkdir(struct user_namespace *mnt_userns, struct inode *dip,
+		     struct dentry *dentry, umode_t mode)
 {
 	int rc = 0;
 	tid_t tid;		/* transaction id */
@@ -868,8 +869,8 @@ static int jfs_link(struct dentry *old_dentry,
  * an intermediate result whose length exceeds PATH_MAX [XPG4.2]
 */
 
-static int jfs_symlink(struct inode *dip, struct dentry *dentry,
-		const char *name)
+static int jfs_symlink(struct user_namespace *mnt_userns, struct inode *dip,
+		       struct dentry *dentry, const char *name)
 {
 	int rc;
 	tid_t tid;
@@ -1058,9 +1059,9 @@ static int jfs_symlink(struct inode *dip, struct dentry *dentry,
  *
  * FUNCTION:	rename a file or directory
  */
-static int jfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		      struct inode *new_dir, struct dentry *new_dentry,
-		      unsigned int flags)
+static int jfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags)
 {
 	struct btstack btstack;
 	ino_t ino;
@@ -1344,8 +1345,8 @@ static int jfs_rename(struct inode *old_dir, struct dentry *old_dentry,
  *
  * FUNCTION:	Create a special file (device)
  */
-static int jfs_mknod(struct inode *dir, struct dentry *dentry,
-		umode_t mode, dev_t rdev)
+static int jfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct jfs_inode_info *jfs_ip;
 	struct btstack btstack;
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index db41e7803163..f9273f6901c8 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -932,6 +932,7 @@ static int jfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int jfs_xattr_set(const struct xattr_handler *handler,
+			 struct user_namespace *mnt_userns,
 			 struct dentry *unused, struct inode *inode,
 			 const char *name, const void *value,
 			 size_t size, int flags)
@@ -950,6 +951,7 @@ static int jfs_xattr_get_os2(const struct xattr_handler *handler,
 }
 
 static int jfs_xattr_set_os2(const struct xattr_handler *handler,
+			     struct user_namespace *mnt_userns,
 			     struct dentry *unused, struct inode *inode,
 			     const char *name, const void *value,
 			     size_t size, int flags)
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index 7a53eed69fef..7e0e62deab53 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -1110,7 +1110,8 @@ static struct dentry *kernfs_iop_lookup(struct inode *dir,
 	return ret;
 }
 
-static int kernfs_iop_mkdir(struct inode *dir, struct dentry *dentry,
+static int kernfs_iop_mkdir(struct user_namespace *mnt_userns,
+			    struct inode *dir, struct dentry *dentry,
 			    umode_t mode)
 {
 	struct kernfs_node *parent = dir->i_private;
@@ -1147,7 +1148,8 @@ static int kernfs_iop_rmdir(struct inode *dir, struct dentry *dentry)
 	return ret;
 }
 
-static int kernfs_iop_rename(struct inode *old_dir, struct dentry *old_dentry,
+static int kernfs_iop_rename(struct user_namespace *mnt_userns,
+			     struct inode *old_dir, struct dentry *old_dentry,
 			     struct inode *new_dir, struct dentry *new_dentry,
 			     unsigned int flags)
 {
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index fc2469a20fed..d73950fc3d57 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -112,7 +112,8 @@ int kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr)
 	return ret;
 }
 
-int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr)
+int kernfs_iop_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		       struct iattr *iattr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct kernfs_node *kn = inode->i_private;
@@ -122,7 +123,7 @@ int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr)
 		return -EINVAL;
 
 	mutex_lock(&kernfs_mutex);
-	error = setattr_prepare(dentry, iattr);
+	error = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (error)
 		goto out;
 
@@ -131,7 +132,7 @@ int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr)
 		goto out;
 
 	/* this ignores size changes */
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 
 out:
 	mutex_unlock(&kernfs_mutex);
@@ -183,7 +184,8 @@ static void kernfs_refresh_inode(struct kernfs_node *kn, struct inode *inode)
 		set_nlink(inode, kn->dir.subdirs + 2);
 }
 
-int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
+int kernfs_iop_getattr(struct user_namespace *mnt_userns,
+		       const struct path *path, struct kstat *stat,
 		       u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
@@ -193,7 +195,7 @@ int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
 	kernfs_refresh_inode(kn, inode);
 	mutex_unlock(&kernfs_mutex);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	return 0;
 }
 
@@ -272,7 +274,8 @@ void kernfs_evict_inode(struct inode *inode)
 	kernfs_put(kn);
 }
 
-int kernfs_iop_permission(struct inode *inode, int mask)
+int kernfs_iop_permission(struct user_namespace *mnt_userns,
+			  struct inode *inode, int mask)
 {
 	struct kernfs_node *kn;
 
@@ -285,7 +288,7 @@ int kernfs_iop_permission(struct inode *inode, int mask)
 	kernfs_refresh_inode(kn, inode);
 	mutex_unlock(&kernfs_mutex);
 
-	return generic_permission(inode, mask);
+	return generic_permission(&init_user_ns, inode, mask);
 }
 
 int kernfs_xattr_get(struct kernfs_node *kn, const char *name,
@@ -319,6 +322,7 @@ static int kernfs_vfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int kernfs_vfs_xattr_set(const struct xattr_handler *handler,
+				struct user_namespace *mnt_userns,
 				struct dentry *unused, struct inode *inode,
 				const char *suffix, const void *value,
 				size_t size, int flags)
@@ -385,6 +389,7 @@ static int kernfs_vfs_user_xattr_rm(struct kernfs_node *kn,
 }
 
 static int kernfs_vfs_user_xattr_set(const struct xattr_handler *handler,
+				     struct user_namespace *mnt_userns,
 				     struct dentry *unused, struct inode *inode,
 				     const char *suffix, const void *value,
 				     size_t size, int flags)
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 7ee97ef59184..ccc3b44f6306 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -89,9 +89,12 @@ extern struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache;
  */
 extern const struct xattr_handler *kernfs_xattr_handlers[];
 void kernfs_evict_inode(struct inode *inode);
-int kernfs_iop_permission(struct inode *inode, int mask);
-int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr);
-int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
+int kernfs_iop_permission(struct user_namespace *mnt_userns,
+			  struct inode *inode, int mask);
+int kernfs_iop_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		       struct iattr *iattr);
+int kernfs_iop_getattr(struct user_namespace *mnt_userns,
+		       const struct path *path, struct kstat *stat,
 		       u32 request_mask, unsigned int query_flags);
 ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size);
 int __kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
diff --git a/fs/libfs.c b/fs/libfs.c
index 1e551766bc52..e2de5401abca 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -27,11 +27,12 @@
 
 #include "internal.h"
 
-int simple_getattr(const struct path *path, struct kstat *stat,
-		   u32 request_mask, unsigned int query_flags)
+int simple_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		   struct kstat *stat, u32 request_mask,
+		   unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	stat->blocks = inode->i_mapping->nrpages << (PAGE_SHIFT - 9);
 	return 0;
 }
@@ -447,9 +448,9 @@ int simple_rmdir(struct inode *dir, struct dentry *dentry)
 }
 EXPORT_SYMBOL(simple_rmdir);
 
-int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
-		  struct inode *new_dir, struct dentry *new_dentry,
-		  unsigned int flags)
+int simple_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		  struct dentry *old_dentry, struct inode *new_dir,
+		  struct dentry *new_dentry, unsigned int flags)
 {
 	struct inode *inode = d_inode(old_dentry);
 	int they_are_dirs = d_is_dir(old_dentry);
@@ -492,18 +493,19 @@ EXPORT_SYMBOL(simple_rename);
  * on simple regular filesystems.  Anything that needs to change on-disk
  * or wire state on size changes needs its own setattr method.
  */
-int simple_setattr(struct dentry *dentry, struct iattr *iattr)
+int simple_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		   struct iattr *iattr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
 
-	error = setattr_prepare(dentry, iattr);
+	error = setattr_prepare(mnt_userns, dentry, iattr);
 	if (error)
 		return error;
 
 	if (iattr->ia_valid & ATTR_SIZE)
 		truncate_setsize(inode, iattr->ia_size);
-	setattr_copy(inode, iattr);
+	setattr_copy(mnt_userns, inode, iattr);
 	mark_inode_dirty(inode);
 	return 0;
 }
@@ -1295,15 +1297,17 @@ static struct dentry *empty_dir_lookup(struct inode *dir, struct dentry *dentry,
 	return ERR_PTR(-ENOENT);
 }
 
-static int empty_dir_getattr(const struct path *path, struct kstat *stat,
+static int empty_dir_getattr(struct user_namespace *mnt_userns,
+			     const struct path *path, struct kstat *stat,
 			     u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	return 0;
 }
 
-static int empty_dir_setattr(struct dentry *dentry, struct iattr *attr)
+static int empty_dir_setattr(struct user_namespace *mnt_userns,
+			     struct dentry *dentry, struct iattr *attr)
 {
 	return -EPERM;
 }
diff --git a/fs/minix/bitmap.c b/fs/minix/bitmap.c
index f4e5e5181a14..9115948c624e 100644
--- a/fs/minix/bitmap.c
+++ b/fs/minix/bitmap.c
@@ -252,7 +252,7 @@ struct inode *minix_new_inode(const struct inode *dir, umode_t mode, int *error)
 		iput(inode);
 		return NULL;
 	}
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode->i_ino = j;
 	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 	inode->i_blocks = 0;
diff --git a/fs/minix/file.c b/fs/minix/file.c
index c50b0a20fcd9..6a7bd2d9eec0 100644
--- a/fs/minix/file.c
+++ b/fs/minix/file.c
@@ -22,12 +22,13 @@ const struct file_operations minix_file_operations = {
 	.splice_read	= generic_file_splice_read,
 };
 
-static int minix_setattr(struct dentry *dentry, struct iattr *attr)
+static int minix_setattr(struct user_namespace *mnt_userns,
+			 struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -41,7 +42,7 @@ static int minix_setattr(struct dentry *dentry, struct iattr *attr)
 		minix_truncate(inode);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index 34f546404aa1..a532a99bbe81 100644
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -652,13 +652,13 @@ static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
 	return err;
 }
 
-int minix_getattr(const struct path *path, struct kstat *stat,
-		  u32 request_mask, unsigned int flags)
+int minix_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		  struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct super_block *sb = path->dentry->d_sb;
 	struct inode *inode = d_inode(path->dentry);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	if (INODE_VERSION(inode) == MINIX_V1)
 		stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
 	else
diff --git a/fs/minix/minix.h b/fs/minix/minix.h
index 168d45d3de73..202173368025 100644
--- a/fs/minix/minix.h
+++ b/fs/minix/minix.h
@@ -51,7 +51,8 @@ extern unsigned long minix_count_free_inodes(struct super_block *sb);
 extern int minix_new_block(struct inode * inode);
 extern void minix_free_block(struct inode *inode, unsigned long block);
 extern unsigned long minix_count_free_blocks(struct super_block *sb);
-extern int minix_getattr(const struct path *, struct kstat *, u32, unsigned int);
+extern int minix_getattr(struct user_namespace *, const struct path *,
+			 struct kstat *, u32, unsigned int);
 extern int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len);
 
 extern void V1_minix_truncate(struct inode *);
diff --git a/fs/minix/namei.c b/fs/minix/namei.c
index 1a6084d2b02e..937fa5fae2b8 100644
--- a/fs/minix/namei.c
+++ b/fs/minix/namei.c
@@ -33,7 +33,8 @@ static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, un
 	return d_splice_alias(inode, dentry);
 }
 
-static int minix_mknod(struct inode * dir, struct dentry *dentry, umode_t mode, dev_t rdev)
+static int minix_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	int error;
 	struct inode *inode;
@@ -51,7 +52,8 @@ static int minix_mknod(struct inode * dir, struct dentry *dentry, umode_t mode,
 	return error;
 }
 
-static int minix_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int minix_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, umode_t mode)
 {
 	int error;
 	struct inode *inode = minix_new_inode(dir, mode, &error);
@@ -63,14 +65,14 @@ static int minix_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 	return error;
 }
 
-static int minix_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		bool excl)
+static int minix_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
-	return minix_mknod(dir, dentry, mode, 0);
+	return minix_mknod(mnt_userns, dir, dentry, mode, 0);
 }
 
-static int minix_symlink(struct inode * dir, struct dentry *dentry,
-	  const char * symname)
+static int minix_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, const char *symname)
 {
 	int err = -ENAMETOOLONG;
 	int i = strlen(symname)+1;
@@ -109,7 +111,8 @@ static int minix_link(struct dentry * old_dentry, struct inode * dir,
 	return add_nondir(dentry, inode);
 }
 
-static int minix_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
+static int minix_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct inode * inode;
 	int err;
@@ -181,8 +184,9 @@ static int minix_rmdir(struct inode * dir, struct dentry *dentry)
 	return err;
 }
 
-static int minix_rename(struct inode * old_dir, struct dentry *old_dentry,
-			struct inode * new_dir, struct dentry *new_dentry,
+static int minix_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry,
 			unsigned int flags)
 {
 	struct inode * old_inode = d_inode(old_dentry);
diff --git a/fs/mount.h b/fs/mount.h
index ce6c376e0bc2..0b6e08cf8afb 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -124,16 +124,6 @@ static inline void get_mnt_ns(struct mnt_namespace *ns)
 
 extern seqlock_t mount_lock;
 
-static inline void lock_mount_hash(void)
-{
-	write_seqlock(&mount_lock);
-}
-
-static inline void unlock_mount_hash(void)
-{
-	write_sequnlock(&mount_lock);
-}
-
 struct proc_mounts {
 	struct mnt_namespace *ns;
 	struct path root;
diff --git a/fs/namei.c b/fs/namei.c
index de74ad2bc6e2..216f16e74351 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -259,7 +259,24 @@ void putname(struct filename *name)
 		__putname(name);
 }
 
-static int check_acl(struct inode *inode, int mask)
+/**
+ * check_acl - perform ACL permission checking
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @inode:	inode to check permissions on
+ * @mask:	right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC ...)
+ *
+ * This function performs the ACL permission checking. Since this function
+ * retrieve POSIX acls it needs to know whether it is called from a blocking or
+ * non-blocking context and thus cares about the MAY_NOT_BLOCK bit.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ */
+static int check_acl(struct user_namespace *mnt_userns,
+		     struct inode *inode, int mask)
 {
 #ifdef CONFIG_FS_POSIX_ACL
 	struct posix_acl *acl;
@@ -271,14 +288,14 @@ static int check_acl(struct inode *inode, int mask)
 		/* no ->get_acl() calls in RCU mode... */
 		if (is_uncached_acl(acl))
 			return -ECHILD;
-	        return posix_acl_permission(inode, acl, mask);
+	        return posix_acl_permission(mnt_userns, inode, acl, mask);
 	}
 
 	acl = get_acl(inode, ACL_TYPE_ACCESS);
 	if (IS_ERR(acl))
 		return PTR_ERR(acl);
 	if (acl) {
-	        int error = posix_acl_permission(inode, acl, mask);
+	        int error = posix_acl_permission(mnt_userns, inode, acl, mask);
 	        posix_acl_release(acl);
 	        return error;
 	}
@@ -287,18 +304,31 @@ static int check_acl(struct inode *inode, int mask)
 	return -EAGAIN;
 }
 
-/*
- * This does the basic UNIX permission checking.
+/**
+ * acl_permission_check - perform basic UNIX permission checking
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @inode:	inode to check permissions on
+ * @mask:	right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC ...)
  *
- * Note that the POSIX ACL check cares about the MAY_NOT_BLOCK bit,
- * for RCU walking.
+ * This function performs the basic UNIX permission checking. Since this
+ * function may retrieve POSIX acls it needs to know whether it is called from a
+ * blocking or non-blocking context and thus cares about the MAY_NOT_BLOCK bit.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
  */
-static int acl_permission_check(struct inode *inode, int mask)
+static int acl_permission_check(struct user_namespace *mnt_userns,
+				struct inode *inode, int mask)
 {
 	unsigned int mode = inode->i_mode;
+	kuid_t i_uid;
 
 	/* Are we the owner? If so, ACL's don't matter */
-	if (likely(uid_eq(current_fsuid(), inode->i_uid))) {
+	i_uid = i_uid_into_mnt(mnt_userns, inode);
+	if (likely(uid_eq(current_fsuid(), i_uid))) {
 		mask &= 7;
 		mode >>= 6;
 		return (mask & ~mode) ? -EACCES : 0;
@@ -306,7 +336,7 @@ static int acl_permission_check(struct inode *inode, int mask)
 
 	/* Do we have ACL's? */
 	if (IS_POSIXACL(inode) && (mode & S_IRWXG)) {
-		int error = check_acl(inode, mask);
+		int error = check_acl(mnt_userns, inode, mask);
 		if (error != -EAGAIN)
 			return error;
 	}
@@ -320,7 +350,8 @@ static int acl_permission_check(struct inode *inode, int mask)
 	 * about? Need to check group ownership if so.
 	 */
 	if (mask & (mode ^ (mode >> 3))) {
-		if (in_group_p(inode->i_gid))
+		kgid_t kgid = i_gid_into_mnt(mnt_userns, inode);
+		if (in_group_p(kgid))
 			mode >>= 3;
 	}
 
@@ -330,6 +361,7 @@ static int acl_permission_check(struct inode *inode, int mask)
 
 /**
  * generic_permission -  check for access rights on a Posix-like filesystem
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode:	inode to check access rights for
  * @mask:	right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC,
  *		%MAY_NOT_BLOCK ...)
@@ -342,25 +374,33 @@ static int acl_permission_check(struct inode *inode, int mask)
  * generic_permission is rcu-walk aware. It returns -ECHILD in case an rcu-walk
  * request cannot be satisfied (eg. requires blocking or too much complexity).
  * It would then be called again in ref-walk mode.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
  */
-int generic_permission(struct inode *inode, int mask)
+int generic_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		       int mask)
 {
 	int ret;
 
 	/*
 	 * Do the basic permission checks.
 	 */
-	ret = acl_permission_check(inode, mask);
+	ret = acl_permission_check(mnt_userns, inode, mask);
 	if (ret != -EACCES)
 		return ret;
 
 	if (S_ISDIR(inode->i_mode)) {
 		/* DACs are overridable for directories */
 		if (!(mask & MAY_WRITE))
-			if (capable_wrt_inode_uidgid(inode,
+			if (capable_wrt_inode_uidgid(mnt_userns, inode,
 						     CAP_DAC_READ_SEARCH))
 				return 0;
-		if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE))
+		if (capable_wrt_inode_uidgid(mnt_userns, inode,
+					     CAP_DAC_OVERRIDE))
 			return 0;
 		return -EACCES;
 	}
@@ -370,7 +410,8 @@ int generic_permission(struct inode *inode, int mask)
 	 */
 	mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
 	if (mask == MAY_READ)
-		if (capable_wrt_inode_uidgid(inode, CAP_DAC_READ_SEARCH))
+		if (capable_wrt_inode_uidgid(mnt_userns, inode,
+					     CAP_DAC_READ_SEARCH))
 			return 0;
 	/*
 	 * Read/write DACs are always overridable.
@@ -378,31 +419,38 @@ int generic_permission(struct inode *inode, int mask)
 	 * at least one exec bit set.
 	 */
 	if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO))
-		if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE))
+		if (capable_wrt_inode_uidgid(mnt_userns, inode,
+					     CAP_DAC_OVERRIDE))
 			return 0;
 
 	return -EACCES;
 }
 EXPORT_SYMBOL(generic_permission);
 
-/*
+/**
+ * do_inode_permission - UNIX permission checking
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @inode:	inode to check permissions on
+ * @mask:	right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC ...)
+ *
  * We _really_ want to just do "generic_permission()" without
  * even looking at the inode->i_op values. So we keep a cache
  * flag in inode->i_opflags, that says "this has not special
  * permission function, use the fast case".
  */
-static inline int do_inode_permission(struct inode *inode, int mask)
+static inline int do_inode_permission(struct user_namespace *mnt_userns,
+				      struct inode *inode, int mask)
 {
 	if (unlikely(!(inode->i_opflags & IOP_FASTPERM))) {
 		if (likely(inode->i_op->permission))
-			return inode->i_op->permission(inode, mask);
+			return inode->i_op->permission(mnt_userns, inode, mask);
 
 		/* This gets set once for the inode lifetime */
 		spin_lock(&inode->i_lock);
 		inode->i_opflags |= IOP_FASTPERM;
 		spin_unlock(&inode->i_lock);
 	}
-	return generic_permission(inode, mask);
+	return generic_permission(mnt_userns, inode, mask);
 }
 
 /**
@@ -427,8 +475,9 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
 
 /**
  * inode_permission - Check for access rights to a given inode
- * @inode: Inode to check permission on
- * @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
+ * @mnt_userns:	User namespace of the mount the inode was found from
+ * @inode:	Inode to check permission on
+ * @mask:	Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
  *
  * Check for read/write/execute permissions on an inode.  We use fs[ug]id for
  * this, letting us set arbitrary permissions for filesystem access without
@@ -436,7 +485,8 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
  *
  * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask.
  */
-int inode_permission(struct inode *inode, int mask)
+int inode_permission(struct user_namespace *mnt_userns,
+		     struct inode *inode, int mask)
 {
 	int retval;
 
@@ -456,11 +506,11 @@ int inode_permission(struct inode *inode, int mask)
 		 * written back improperly if their true value is unknown
 		 * to the vfs.
 		 */
-		if (HAS_UNMAPPED_ID(inode))
+		if (HAS_UNMAPPED_ID(mnt_userns, inode))
 			return -EACCES;
 	}
 
-	retval = do_inode_permission(inode, mask);
+	retval = do_inode_permission(mnt_userns, inode, mask);
 	if (retval)
 		return retval;
 
@@ -960,11 +1010,16 @@ int sysctl_protected_regular __read_mostly;
  */
 static inline int may_follow_link(struct nameidata *nd, const struct inode *inode)
 {
+	struct user_namespace *mnt_userns;
+	kuid_t i_uid;
+
 	if (!sysctl_protected_symlinks)
 		return 0;
 
+	mnt_userns = mnt_user_ns(nd->path.mnt);
+	i_uid = i_uid_into_mnt(mnt_userns, inode);
 	/* Allowed if owner and follower match. */
-	if (uid_eq(current_cred()->fsuid, inode->i_uid))
+	if (uid_eq(current_cred()->fsuid, i_uid))
 		return 0;
 
 	/* Allowed if parent directory not sticky and world-writable. */
@@ -972,7 +1027,7 @@ static inline int may_follow_link(struct nameidata *nd, const struct inode *inod
 		return 0;
 
 	/* Allowed if parent directory and link owner match. */
-	if (uid_valid(nd->dir_uid) && uid_eq(nd->dir_uid, inode->i_uid))
+	if (uid_valid(nd->dir_uid) && uid_eq(nd->dir_uid, i_uid))
 		return 0;
 
 	if (nd->flags & LOOKUP_RCU)
@@ -985,6 +1040,7 @@ static inline int may_follow_link(struct nameidata *nd, const struct inode *inod
 
 /**
  * safe_hardlink_source - Check for safe hardlink conditions
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode: the source inode to hardlink from
  *
  * Return false if at least one of the following conditions:
@@ -995,7 +1051,8 @@ static inline int may_follow_link(struct nameidata *nd, const struct inode *inod
  *
  * Otherwise returns true.
  */
-static bool safe_hardlink_source(struct inode *inode)
+static bool safe_hardlink_source(struct user_namespace *mnt_userns,
+				 struct inode *inode)
 {
 	umode_t mode = inode->i_mode;
 
@@ -1012,7 +1069,7 @@ static bool safe_hardlink_source(struct inode *inode)
 		return false;
 
 	/* Hardlinking to unreadable or unwritable sources is dangerous. */
-	if (inode_permission(inode, MAY_READ | MAY_WRITE))
+	if (inode_permission(mnt_userns, inode, MAY_READ | MAY_WRITE))
 		return false;
 
 	return true;
@@ -1020,6 +1077,7 @@ static bool safe_hardlink_source(struct inode *inode)
 
 /**
  * may_linkat - Check permissions for creating a hardlink
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @link: the source to hardlink from
  *
  * Block hardlink when all of:
@@ -1028,14 +1086,21 @@ static bool safe_hardlink_source(struct inode *inode)
  *  - hardlink source is unsafe (see safe_hardlink_source() above)
  *  - not CAP_FOWNER in a namespace with the inode owner uid mapped
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ *
  * Returns 0 if successful, -ve on error.
  */
-int may_linkat(struct path *link)
+int may_linkat(struct user_namespace *mnt_userns, struct path *link)
 {
 	struct inode *inode = link->dentry->d_inode;
 
 	/* Inode writeback is not safe when the uid or gid are invalid. */
-	if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid))
+	if (!uid_valid(i_uid_into_mnt(mnt_userns, inode)) ||
+	    !gid_valid(i_gid_into_mnt(mnt_userns, inode)))
 		return -EOVERFLOW;
 
 	if (!sysctl_protected_hardlinks)
@@ -1044,7 +1109,8 @@ int may_linkat(struct path *link)
 	/* Source inode owner (or CAP_FOWNER) can hardlink all they like,
 	 * otherwise, it must be a safe source.
 	 */
-	if (safe_hardlink_source(inode) || inode_owner_or_capable(inode))
+	if (safe_hardlink_source(mnt_userns, inode) ||
+	    inode_owner_or_capable(mnt_userns, inode))
 		return 0;
 
 	audit_log_path_denied(AUDIT_ANOM_LINK, "linkat");
@@ -1055,6 +1121,7 @@ int may_linkat(struct path *link)
  * may_create_in_sticky - Check whether an O_CREAT open in a sticky directory
  *			  should be allowed, or not, on files that already
  *			  exist.
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @dir_mode: mode bits of directory
  * @dir_uid: owner of directory
  * @inode: the inode of the file to open
@@ -1070,16 +1137,25 @@ int may_linkat(struct path *link)
  * the directory doesn't have to be world writable: being group writable will
  * be enough.
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ *
  * Returns 0 if the open is allowed, -ve on error.
  */
-static int may_create_in_sticky(umode_t dir_mode, kuid_t dir_uid,
-				struct inode * const inode)
+static int may_create_in_sticky(struct user_namespace *mnt_userns,
+				struct nameidata *nd, struct inode *const inode)
 {
+	umode_t dir_mode = nd->dir_mode;
+	kuid_t dir_uid = nd->dir_uid;
+
 	if ((!sysctl_protected_fifos && S_ISFIFO(inode->i_mode)) ||
 	    (!sysctl_protected_regular && S_ISREG(inode->i_mode)) ||
 	    likely(!(dir_mode & S_ISVTX)) ||
-	    uid_eq(inode->i_uid, dir_uid) ||
-	    uid_eq(current_fsuid(), inode->i_uid))
+	    uid_eq(i_uid_into_mnt(mnt_userns, inode), dir_uid) ||
+	    uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode)))
 		return 0;
 
 	if (likely(dir_mode & 0002) ||
@@ -1569,14 +1645,15 @@ static struct dentry *lookup_slow(const struct qstr *name,
 	return res;
 }
 
-static inline int may_lookup(struct nameidata *nd)
+static inline int may_lookup(struct user_namespace *mnt_userns,
+			     struct nameidata *nd)
 {
 	if (nd->flags & LOOKUP_RCU) {
-		int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
+		int err = inode_permission(mnt_userns, nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
 		if (err != -ECHILD || !try_to_unlazy(nd))
 			return err;
 	}
-	return inode_permission(nd->inode, MAY_EXEC);
+	return inode_permission(mnt_userns, nd->inode, MAY_EXEC);
 }
 
 static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq)
@@ -2122,11 +2199,13 @@ static int link_path_walk(const char *name, struct nameidata *nd)
 
 	/* At this point we know we have a real path component. */
 	for(;;) {
+		struct user_namespace *mnt_userns;
 		const char *link;
 		u64 hash_len;
 		int type;
 
-		err = may_lookup(nd);
+		mnt_userns = mnt_user_ns(nd->path.mnt);
+		err = may_lookup(mnt_userns, nd);
 		if (err)
 			return err;
 
@@ -2174,7 +2253,7 @@ static int link_path_walk(const char *name, struct nameidata *nd)
 OK:
 			/* pathname or trailing symlink, done */
 			if (!depth) {
-				nd->dir_uid = nd->inode->i_uid;
+				nd->dir_uid = i_uid_into_mnt(mnt_userns, nd->inode);
 				nd->dir_mode = nd->inode->i_mode;
 				nd->flags &= ~LOOKUP_PARENT;
 				return 0;
@@ -2511,7 +2590,7 @@ static int lookup_one_len_common(const char *name, struct dentry *base,
 			return err;
 	}
 
-	return inode_permission(base->d_inode, MAY_EXEC);
+	return inode_permission(&init_user_ns, base->d_inode, MAY_EXEC);
 }
 
 /**
@@ -2656,15 +2735,16 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
 }
 EXPORT_SYMBOL(user_path_at_empty);
 
-int __check_sticky(struct inode *dir, struct inode *inode)
+int __check_sticky(struct user_namespace *mnt_userns, struct inode *dir,
+		   struct inode *inode)
 {
 	kuid_t fsuid = current_fsuid();
 
-	if (uid_eq(inode->i_uid, fsuid))
+	if (uid_eq(i_uid_into_mnt(mnt_userns, inode), fsuid))
 		return 0;
-	if (uid_eq(dir->i_uid, fsuid))
+	if (uid_eq(i_uid_into_mnt(mnt_userns, dir), fsuid))
 		return 0;
-	return !capable_wrt_inode_uidgid(inode, CAP_FOWNER);
+	return !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FOWNER);
 }
 EXPORT_SYMBOL(__check_sticky);
 
@@ -2688,7 +2768,8 @@ EXPORT_SYMBOL(__check_sticky);
  * 11. We don't allow removal of NFS sillyrenamed files; it's handled by
  *     nfs_async_unlink().
  */
-static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
+static int may_delete(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *victim, bool isdir)
 {
 	struct inode *inode = d_backing_inode(victim);
 	int error;
@@ -2700,19 +2781,21 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
 	BUG_ON(victim->d_parent->d_inode != dir);
 
 	/* Inode writeback is not safe when the uid or gid are invalid. */
-	if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid))
+	if (!uid_valid(i_uid_into_mnt(mnt_userns, inode)) ||
+	    !gid_valid(i_gid_into_mnt(mnt_userns, inode)))
 		return -EOVERFLOW;
 
 	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 
-	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	error = inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 	if (IS_APPEND(dir))
 		return -EPERM;
 
-	if (check_sticky(dir, inode) || IS_APPEND(inode) ||
-	    IS_IMMUTABLE(inode) || IS_SWAPFILE(inode) || HAS_UNMAPPED_ID(inode))
+	if (check_sticky(mnt_userns, dir, inode) || IS_APPEND(inode) ||
+	    IS_IMMUTABLE(inode) || IS_SWAPFILE(inode) ||
+	    HAS_UNMAPPED_ID(mnt_userns, inode))
 		return -EPERM;
 	if (isdir) {
 		if (!d_is_dir(victim))
@@ -2737,7 +2820,8 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
  *  4. We should have write and exec permissions on dir
  *  5. We can't do it if dir is immutable (done in permission())
  */
-static inline int may_create(struct inode *dir, struct dentry *child)
+static inline int may_create(struct user_namespace *mnt_userns,
+			     struct inode *dir, struct dentry *child)
 {
 	struct user_namespace *s_user_ns;
 	audit_inode_child(dir, child, AUDIT_TYPE_CHILD_CREATE);
@@ -2746,10 +2830,10 @@ static inline int may_create(struct inode *dir, struct dentry *child)
 	if (IS_DEADDIR(dir))
 		return -ENOENT;
 	s_user_ns = dir->i_sb->s_user_ns;
-	if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
-	    !kgid_has_mapping(s_user_ns, current_fsgid()))
+	if (!kuid_has_mapping(s_user_ns, fsuid_into_mnt(mnt_userns)) ||
+	    !kgid_has_mapping(s_user_ns, fsgid_into_mnt(mnt_userns)))
 		return -EOVERFLOW;
-	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	return inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
 }
 
 /*
@@ -2796,10 +2880,26 @@ void unlock_rename(struct dentry *p1, struct dentry *p2)
 }
 EXPORT_SYMBOL(unlock_rename);
 
-int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		bool want_excl)
+/**
+ * vfs_create - create new file
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dir:	inode of @dentry
+ * @dentry:	pointer to dentry of the base directory
+ * @mode:	mode of the new file
+ * @want_excl:	whether the file must not yet exist
+ *
+ * Create a new file.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ */
+int vfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+	       struct dentry *dentry, umode_t mode, bool want_excl)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt_userns, dir, dentry);
 	if (error)
 		return error;
 
@@ -2810,7 +2910,7 @@ int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	error = security_inode_create(dir, dentry, mode);
 	if (error)
 		return error;
-	error = dir->i_op->create(dir, dentry, mode, want_excl);
+	error = dir->i_op->create(mnt_userns, dir, dentry, mode, want_excl);
 	if (!error)
 		fsnotify_create(dir, dentry);
 	return error;
@@ -2822,7 +2922,7 @@ int vfs_mkobj(struct dentry *dentry, umode_t mode,
 		void *arg)
 {
 	struct inode *dir = dentry->d_parent->d_inode;
-	int error = may_create(dir, dentry);
+	int error = may_create(&init_user_ns, dir, dentry);
 	if (error)
 		return error;
 
@@ -2844,7 +2944,8 @@ bool may_open_dev(const struct path *path)
 		!(path->mnt->mnt_sb->s_iflags & SB_I_NODEV);
 }
 
-static int may_open(const struct path *path, int acc_mode, int flag)
+static int may_open(struct user_namespace *mnt_userns, const struct path *path,
+		    int acc_mode, int flag)
 {
 	struct dentry *dentry = path->dentry;
 	struct inode *inode = dentry->d_inode;
@@ -2879,7 +2980,7 @@ static int may_open(const struct path *path, int acc_mode, int flag)
 		break;
 	}
 
-	error = inode_permission(inode, MAY_OPEN | acc_mode);
+	error = inode_permission(mnt_userns, inode, MAY_OPEN | acc_mode);
 	if (error)
 		return error;
 
@@ -2894,13 +2995,13 @@ static int may_open(const struct path *path, int acc_mode, int flag)
 	}
 
 	/* O_NOATIME can only be set by the owner or superuser */
-	if (flag & O_NOATIME && !inode_owner_or_capable(inode))
+	if (flag & O_NOATIME && !inode_owner_or_capable(mnt_userns, inode))
 		return -EPERM;
 
 	return 0;
 }
 
-static int handle_truncate(struct file *filp)
+static int handle_truncate(struct user_namespace *mnt_userns, struct file *filp)
 {
 	const struct path *path = &filp->f_path;
 	struct inode *inode = path->dentry->d_inode;
@@ -2914,7 +3015,7 @@ static int handle_truncate(struct file *filp)
 	if (!error)
 		error = security_path_truncate(path);
 	if (!error) {
-		error = do_truncate(path->dentry, 0,
+		error = do_truncate(mnt_userns, path->dentry, 0,
 				    ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
 				    filp);
 	}
@@ -2929,7 +3030,9 @@ static inline int open_to_namei_flags(int flag)
 	return flag;
 }
 
-static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t mode)
+static int may_o_create(struct user_namespace *mnt_userns,
+			const struct path *dir, struct dentry *dentry,
+			umode_t mode)
 {
 	struct user_namespace *s_user_ns;
 	int error = security_path_mknod(dir, dentry, mode, 0);
@@ -2937,11 +3040,12 @@ static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t m
 		return error;
 
 	s_user_ns = dir->dentry->d_sb->s_user_ns;
-	if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
-	    !kgid_has_mapping(s_user_ns, current_fsgid()))
+	if (!kuid_has_mapping(s_user_ns, fsuid_into_mnt(mnt_userns)) ||
+	    !kgid_has_mapping(s_user_ns, fsgid_into_mnt(mnt_userns)))
 		return -EOVERFLOW;
 
-	error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC);
+	error = inode_permission(mnt_userns, dir->dentry->d_inode,
+				 MAY_WRITE | MAY_EXEC);
 	if (error)
 		return error;
 
@@ -3020,6 +3124,7 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
 				  const struct open_flags *op,
 				  bool got_write)
 {
+	struct user_namespace *mnt_userns;
 	struct dentry *dir = nd->path.dentry;
 	struct inode *dir_inode = dir->d_inode;
 	int open_flag = op->open_flag;
@@ -3067,13 +3172,15 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
 	 */
 	if (unlikely(!got_write))
 		open_flag &= ~O_TRUNC;
+	mnt_userns = mnt_user_ns(nd->path.mnt);
 	if (open_flag & O_CREAT) {
 		if (open_flag & O_EXCL)
 			open_flag &= ~O_TRUNC;
 		if (!IS_POSIXACL(dir->d_inode))
 			mode &= ~current_umask();
 		if (likely(got_write))
-			create_error = may_o_create(&nd->path, dentry, mode);
+			create_error = may_o_create(mnt_userns, &nd->path,
+						    dentry, mode);
 		else
 			create_error = -EROFS;
 	}
@@ -3108,8 +3215,9 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
 			error = -EACCES;
 			goto out_dput;
 		}
-		error = dir_inode->i_op->create(dir_inode, dentry, mode,
-						open_flag & O_EXCL);
+
+		error = dir_inode->i_op->create(mnt_userns, dir_inode, dentry,
+						mode, open_flag & O_EXCL);
 		if (error)
 			goto out_dput;
 	}
@@ -3213,6 +3321,7 @@ finish_lookup:
 static int do_open(struct nameidata *nd,
 		   struct file *file, const struct open_flags *op)
 {
+	struct user_namespace *mnt_userns;
 	int open_flag = op->open_flag;
 	bool do_truncate;
 	int acc_mode;
@@ -3225,12 +3334,13 @@ static int do_open(struct nameidata *nd,
 	}
 	if (!(file->f_mode & FMODE_CREATED))
 		audit_inode(nd->name, nd->path.dentry, 0);
+	mnt_userns = mnt_user_ns(nd->path.mnt);
 	if (open_flag & O_CREAT) {
 		if ((open_flag & O_EXCL) && !(file->f_mode & FMODE_CREATED))
 			return -EEXIST;
 		if (d_is_dir(nd->path.dentry))
 			return -EISDIR;
-		error = may_create_in_sticky(nd->dir_mode, nd->dir_uid,
+		error = may_create_in_sticky(mnt_userns, nd,
 					     d_backing_inode(nd->path.dentry));
 		if (unlikely(error))
 			return error;
@@ -3250,13 +3360,13 @@ static int do_open(struct nameidata *nd,
 			return error;
 		do_truncate = true;
 	}
-	error = may_open(&nd->path, acc_mode, open_flag);
+	error = may_open(mnt_userns, &nd->path, acc_mode, open_flag);
 	if (!error && !(file->f_mode & FMODE_OPENED))
 		error = vfs_open(&nd->path, file);
 	if (!error)
 		error = ima_file_check(file, op->acc_mode);
 	if (!error && do_truncate)
-		error = handle_truncate(file);
+		error = handle_truncate(mnt_userns, file);
 	if (unlikely(error > 0)) {
 		WARN_ON(1);
 		error = -EINVAL;
@@ -3266,7 +3376,23 @@ static int do_open(struct nameidata *nd,
 	return error;
 }
 
-struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
+/**
+ * vfs_tmpfile - create tmpfile
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dentry:	pointer to dentry of the base directory
+ * @mode:	mode of the new tmpfile
+ * @open_flags:	flags
+ *
+ * Create a temporary file.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ */
+struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns,
+			   struct dentry *dentry, umode_t mode, int open_flag)
 {
 	struct dentry *child = NULL;
 	struct inode *dir = dentry->d_inode;
@@ -3274,7 +3400,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
 	int error;
 
 	/* we want directory to be writable */
-	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	error = inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
 	if (error)
 		goto out_err;
 	error = -EOPNOTSUPP;
@@ -3284,7 +3410,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
 	child = d_alloc(dentry, &slash_name);
 	if (unlikely(!child))
 		goto out_err;
-	error = dir->i_op->tmpfile(dir, child, mode);
+	error = dir->i_op->tmpfile(mnt_userns, dir, child, mode);
 	if (error)
 		goto out_err;
 	error = -ENOENT;
@@ -3296,7 +3422,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
 		inode->i_state |= I_LINKABLE;
 		spin_unlock(&inode->i_lock);
 	}
-	ima_post_create_tmpfile(inode);
+	ima_post_create_tmpfile(mnt_userns, inode);
 	return child;
 
 out_err:
@@ -3309,6 +3435,7 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
 		const struct open_flags *op,
 		struct file *file)
 {
+	struct user_namespace *mnt_userns;
 	struct dentry *child;
 	struct path path;
 	int error = path_lookupat(nd, flags | LOOKUP_DIRECTORY, &path);
@@ -3317,7 +3444,8 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
 	error = mnt_want_write(path.mnt);
 	if (unlikely(error))
 		goto out;
-	child = vfs_tmpfile(path.dentry, op->mode, op->open_flag);
+	mnt_userns = mnt_user_ns(path.mnt);
+	child = vfs_tmpfile(mnt_userns, path.dentry, op->mode, op->open_flag);
 	error = PTR_ERR(child);
 	if (IS_ERR(child))
 		goto out2;
@@ -3325,7 +3453,7 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
 	path.dentry = child;
 	audit_inode(nd->name, child, 0);
 	/* Don't check for other permissions, the inode was just created */
-	error = may_open(&path, 0, op->open_flag);
+	error = may_open(mnt_userns, &path, 0, op->open_flag);
 	if (!error)
 		error = vfs_open(&path, file);
 out2:
@@ -3527,10 +3655,27 @@ inline struct dentry *user_path_create(int dfd, const char __user *pathname,
 }
 EXPORT_SYMBOL(user_path_create);
 
-int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+/**
+ * vfs_mknod - create device node or file
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dir:	inode of @dentry
+ * @dentry:	pointer to dentry of the base directory
+ * @mode:	mode of the new device node or file
+ * @dev:	device number of device to create
+ *
+ * Create a device node or file.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ */
+int vfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+	      struct dentry *dentry, umode_t mode, dev_t dev)
 {
 	bool is_whiteout = S_ISCHR(mode) && dev == WHITEOUT_DEV;
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt_userns, dir, dentry);
 
 	if (error)
 		return error;
@@ -3550,7 +3695,7 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
 	if (error)
 		return error;
 
-	error = dir->i_op->mknod(dir, dentry, mode, dev);
+	error = dir->i_op->mknod(mnt_userns, dir, dentry, mode, dev);
 	if (!error)
 		fsnotify_create(dir, dentry);
 	return error;
@@ -3577,6 +3722,7 @@ static int may_mknod(umode_t mode)
 static long do_mknodat(int dfd, const char __user *filename, umode_t mode,
 		unsigned int dev)
 {
+	struct user_namespace *mnt_userns;
 	struct dentry *dentry;
 	struct path path;
 	int error;
@@ -3595,18 +3741,22 @@ retry:
 	error = security_path_mknod(&path, dentry, mode, dev);
 	if (error)
 		goto out;
+
+	mnt_userns = mnt_user_ns(path.mnt);
 	switch (mode & S_IFMT) {
 		case 0: case S_IFREG:
-			error = vfs_create(path.dentry->d_inode,dentry,mode,true);
+			error = vfs_create(mnt_userns, path.dentry->d_inode,
+					   dentry, mode, true);
 			if (!error)
-				ima_post_path_mknod(dentry);
+				ima_post_path_mknod(mnt_userns, dentry);
 			break;
 		case S_IFCHR: case S_IFBLK:
-			error = vfs_mknod(path.dentry->d_inode,dentry,mode,
-					new_decode_dev(dev));
+			error = vfs_mknod(mnt_userns, path.dentry->d_inode,
+					  dentry, mode, new_decode_dev(dev));
 			break;
 		case S_IFIFO: case S_IFSOCK:
-			error = vfs_mknod(path.dentry->d_inode,dentry,mode,0);
+			error = vfs_mknod(mnt_userns, path.dentry->d_inode,
+					  dentry, mode, 0);
 			break;
 	}
 out:
@@ -3629,9 +3779,25 @@ SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, d
 	return do_mknodat(AT_FDCWD, filename, mode, dev);
 }
 
-int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+/**
+ * vfs_mkdir - create directory
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dir:	inode of @dentry
+ * @dentry:	pointer to dentry of the base directory
+ * @mode:	mode of the new directory
+ *
+ * Create a directory.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ */
+int vfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+	      struct dentry *dentry, umode_t mode)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt_userns, dir, dentry);
 	unsigned max_links = dir->i_sb->s_max_links;
 
 	if (error)
@@ -3648,7 +3814,7 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	if (max_links && dir->i_nlink >= max_links)
 		return -EMLINK;
 
-	error = dir->i_op->mkdir(dir, dentry, mode);
+	error = dir->i_op->mkdir(mnt_userns, dir, dentry, mode);
 	if (!error)
 		fsnotify_mkdir(dir, dentry);
 	return error;
@@ -3670,8 +3836,12 @@ retry:
 	if (!IS_POSIXACL(path.dentry->d_inode))
 		mode &= ~current_umask();
 	error = security_path_mkdir(&path, dentry, mode);
-	if (!error)
-		error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
+	if (!error) {
+		struct user_namespace *mnt_userns;
+		mnt_userns = mnt_user_ns(path.mnt);
+		error = vfs_mkdir(mnt_userns, path.dentry->d_inode, dentry,
+				  mode);
+	}
 	done_path_create(&path, dentry);
 	if (retry_estale(error, lookup_flags)) {
 		lookup_flags |= LOOKUP_REVAL;
@@ -3690,9 +3860,24 @@ SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode)
 	return do_mkdirat(AT_FDCWD, pathname, mode);
 }
 
-int vfs_rmdir(struct inode *dir, struct dentry *dentry)
+/**
+ * vfs_rmdir - remove directory
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dir:	inode of @dentry
+ * @dentry:	pointer to dentry of the base directory
+ *
+ * Remove a directory.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ */
+int vfs_rmdir(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry)
 {
-	int error = may_delete(dir, dentry, 1);
+	int error = may_delete(mnt_userns, dir, dentry, 1);
 
 	if (error)
 		return error;
@@ -3732,6 +3917,7 @@ EXPORT_SYMBOL(vfs_rmdir);
 
 long do_rmdir(int dfd, struct filename *name)
 {
+	struct user_namespace *mnt_userns;
 	int error = 0;
 	struct dentry *dentry;
 	struct path path;
@@ -3772,7 +3958,8 @@ retry:
 	error = security_path_rmdir(&path, dentry);
 	if (error)
 		goto exit3;
-	error = vfs_rmdir(path.dentry->d_inode, dentry);
+	mnt_userns = mnt_user_ns(path.mnt);
+	error = vfs_rmdir(mnt_userns, path.dentry->d_inode, dentry);
 exit3:
 	dput(dentry);
 exit2:
@@ -3795,6 +3982,7 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname)
 
 /**
  * vfs_unlink - unlink a filesystem object
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @dir:	parent directory
  * @dentry:	victim
  * @delegated_inode: returns victim inode, if the inode is delegated.
@@ -3810,11 +3998,18 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname)
  * Alternatively, a caller may pass NULL for delegated_inode.  This may
  * be appropriate for callers that expect the underlying filesystem not
  * to be NFS exported.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
  */
-int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode)
+int vfs_unlink(struct user_namespace *mnt_userns, struct inode *dir,
+	       struct dentry *dentry, struct inode **delegated_inode)
 {
 	struct inode *target = dentry->d_inode;
-	int error = may_delete(dir, dentry, 0);
+	int error = may_delete(mnt_userns, dir, dentry, 0);
 
 	if (error)
 		return error;
@@ -3885,6 +4080,8 @@ retry_deleg:
 	dentry = __lookup_hash(&last, path.dentry, lookup_flags);
 	error = PTR_ERR(dentry);
 	if (!IS_ERR(dentry)) {
+		struct user_namespace *mnt_userns;
+
 		/* Why not before? Because we want correct error value */
 		if (last.name[last.len])
 			goto slashes;
@@ -3895,7 +4092,9 @@ retry_deleg:
 		error = security_path_unlink(&path, dentry);
 		if (error)
 			goto exit2;
-		error = vfs_unlink(path.dentry->d_inode, dentry, &delegated_inode);
+		mnt_userns = mnt_user_ns(path.mnt);
+		error = vfs_unlink(mnt_userns, path.dentry->d_inode, dentry,
+				   &delegated_inode);
 exit2:
 		dput(dentry);
 	}
@@ -3944,9 +4143,25 @@ SYSCALL_DEFINE1(unlink, const char __user *, pathname)
 	return do_unlinkat(AT_FDCWD, getname(pathname));
 }
 
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
+/**
+ * vfs_symlink - create symlink
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dir:	inode of @dentry
+ * @dentry:	pointer to dentry of the base directory
+ * @oldname:	name of the file to link to
+ *
+ * Create a symlink.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
+ */
+int vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		struct dentry *dentry, const char *oldname)
 {
-	int error = may_create(dir, dentry);
+	int error = may_create(mnt_userns, dir, dentry);
 
 	if (error)
 		return error;
@@ -3958,7 +4173,7 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
 	if (error)
 		return error;
 
-	error = dir->i_op->symlink(dir, dentry, oldname);
+	error = dir->i_op->symlink(mnt_userns, dir, dentry, oldname);
 	if (!error)
 		fsnotify_create(dir, dentry);
 	return error;
@@ -3984,8 +4199,13 @@ retry:
 		goto out_putname;
 
 	error = security_path_symlink(&path, dentry, from->name);
-	if (!error)
-		error = vfs_symlink(path.dentry->d_inode, dentry, from->name);
+	if (!error) {
+		struct user_namespace *mnt_userns;
+
+		mnt_userns = mnt_user_ns(path.mnt);
+		error = vfs_symlink(mnt_userns, path.dentry->d_inode, dentry,
+				    from->name);
+	}
 	done_path_create(&path, dentry);
 	if (retry_estale(error, lookup_flags)) {
 		lookup_flags |= LOOKUP_REVAL;
@@ -4010,6 +4230,7 @@ SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newn
 /**
  * vfs_link - create a new link
  * @old_dentry:	object to be linked
+ * @mnt_userns:	the user namespace of the mount
  * @dir:	new parent
  * @new_dentry:	where to create the new link
  * @delegated_inode: returns inode needing a delegation break
@@ -4025,8 +4246,16 @@ SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newn
  * Alternatively, a caller may pass NULL for delegated_inode.  This may
  * be appropriate for callers that expect the underlying filesystem not
  * to be NFS exported.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then take
+ * care to map the inode according to @mnt_userns before checking permissions.
+ * On non-idmapped mounts or if permission checking is to be performed on the
+ * raw inode simply passs init_user_ns.
  */
-int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode)
+int vfs_link(struct dentry *old_dentry, struct user_namespace *mnt_userns,
+	     struct inode *dir, struct dentry *new_dentry,
+	     struct inode **delegated_inode)
 {
 	struct inode *inode = old_dentry->d_inode;
 	unsigned max_links = dir->i_sb->s_max_links;
@@ -4035,7 +4264,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
 	if (!inode)
 		return -ENOENT;
 
-	error = may_create(dir, new_dentry);
+	error = may_create(mnt_userns, dir, new_dentry);
 	if (error)
 		return error;
 
@@ -4052,7 +4281,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
 	 * be writen back improperly if their true value is unknown to
 	 * the vfs.
 	 */
-	if (HAS_UNMAPPED_ID(inode))
+	if (HAS_UNMAPPED_ID(mnt_userns, inode))
 		return -EPERM;
 	if (!dir->i_op->link)
 		return -EPERM;
@@ -4099,6 +4328,7 @@ EXPORT_SYMBOL(vfs_link);
 static int do_linkat(int olddfd, const char __user *oldname, int newdfd,
 	      const char __user *newname, int flags)
 {
+	struct user_namespace *mnt_userns;
 	struct dentry *new_dentry;
 	struct path old_path, new_path;
 	struct inode *delegated_inode = NULL;
@@ -4134,13 +4364,15 @@ retry:
 	error = -EXDEV;
 	if (old_path.mnt != new_path.mnt)
 		goto out_dput;
-	error = may_linkat(&old_path);
+	mnt_userns = mnt_user_ns(new_path.mnt);
+	error = may_linkat(mnt_userns, &old_path);
 	if (unlikely(error))
 		goto out_dput;
 	error = security_path_link(old_path.dentry, &new_path, new_dentry);
 	if (error)
 		goto out_dput;
-	error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode);
+	error = vfs_link(old_path.dentry, mnt_userns, new_path.dentry->d_inode,
+			 new_dentry, &delegated_inode);
 out_dput:
 	done_path_create(&new_path, new_dentry);
 	if (delegated_inode) {
@@ -4174,12 +4406,14 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
 
 /**
  * vfs_rename - rename a filesystem object
- * @old_dir:	parent of source
- * @old_dentry:	source
- * @new_dir:	parent of destination
- * @new_dentry:	destination
- * @delegated_inode: returns an inode needing a delegation break
- * @flags:	rename flags
+ * @old_mnt_userns:	old user namespace of the mount the inode was found from
+ * @old_dir:		parent of source
+ * @old_dentry:		source
+ * @new_mnt_userns:	new user namespace of the mount the inode was found from
+ * @new_dir:		parent of destination
+ * @new_dentry:		destination
+ * @delegated_inode:	returns an inode needing a delegation break
+ * @flags:		rename flags
  *
  * The caller must hold multiple mutexes--see lock_rename()).
  *
@@ -4222,11 +4456,14 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
  *	   ->i_mutex on parents, which works but leads to some truly excessive
  *	   locking].
  */
-int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-	       struct inode *new_dir, struct dentry *new_dentry,
-	       struct inode **delegated_inode, unsigned int flags)
+int vfs_rename(struct renamedata *rd)
 {
 	int error;
+	struct inode *old_dir = rd->old_dir, *new_dir = rd->new_dir;
+	struct dentry *old_dentry = rd->old_dentry;
+	struct dentry *new_dentry = rd->new_dentry;
+	struct inode **delegated_inode = rd->delegated_inode;
+	unsigned int flags = rd->flags;
 	bool is_dir = d_is_dir(old_dentry);
 	struct inode *source = old_dentry->d_inode;
 	struct inode *target = new_dentry->d_inode;
@@ -4237,19 +4474,21 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if (source == target)
 		return 0;
 
-	error = may_delete(old_dir, old_dentry, is_dir);
+	error = may_delete(rd->old_mnt_userns, old_dir, old_dentry, is_dir);
 	if (error)
 		return error;
 
 	if (!target) {
-		error = may_create(new_dir, new_dentry);
+		error = may_create(rd->new_mnt_userns, new_dir, new_dentry);
 	} else {
 		new_is_dir = d_is_dir(new_dentry);
 
 		if (!(flags & RENAME_EXCHANGE))
-			error = may_delete(new_dir, new_dentry, is_dir);
+			error = may_delete(rd->new_mnt_userns, new_dir,
+					   new_dentry, is_dir);
 		else
-			error = may_delete(new_dir, new_dentry, new_is_dir);
+			error = may_delete(rd->new_mnt_userns, new_dir,
+					   new_dentry, new_is_dir);
 	}
 	if (error)
 		return error;
@@ -4263,12 +4502,14 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	 */
 	if (new_dir != old_dir) {
 		if (is_dir) {
-			error = inode_permission(source, MAY_WRITE);
+			error = inode_permission(rd->old_mnt_userns, source,
+						 MAY_WRITE);
 			if (error)
 				return error;
 		}
 		if ((flags & RENAME_EXCHANGE) && new_is_dir) {
-			error = inode_permission(target, MAY_WRITE);
+			error = inode_permission(rd->new_mnt_userns, target,
+						 MAY_WRITE);
 			if (error)
 				return error;
 		}
@@ -4308,8 +4549,8 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 		if (error)
 			goto out;
 	}
-	error = old_dir->i_op->rename(old_dir, old_dentry,
-				       new_dir, new_dentry, flags);
+	error = old_dir->i_op->rename(rd->new_mnt_userns, old_dir, old_dentry,
+				      new_dir, new_dentry, flags);
 	if (error)
 		goto out;
 
@@ -4350,6 +4591,7 @@ EXPORT_SYMBOL(vfs_rename);
 int do_renameat2(int olddfd, struct filename *from, int newdfd,
 		 struct filename *to, unsigned int flags)
 {
+	struct renamedata rd;
 	struct dentry *old_dentry, *new_dentry;
 	struct dentry *trap;
 	struct path old_path, new_path;
@@ -4453,9 +4695,16 @@ retry_deleg:
 				     &new_path, new_dentry, flags);
 	if (error)
 		goto exit5;
-	error = vfs_rename(old_path.dentry->d_inode, old_dentry,
-			   new_path.dentry->d_inode, new_dentry,
-			   &delegated_inode, flags);
+
+	rd.old_dir	   = old_path.dentry->d_inode;
+	rd.old_dentry	   = old_dentry;
+	rd.old_mnt_userns  = mnt_user_ns(old_path.mnt);
+	rd.new_dir	   = new_path.dentry->d_inode;
+	rd.new_dentry	   = new_dentry;
+	rd.new_mnt_userns  = mnt_user_ns(new_path.mnt);
+	rd.delegated_inode = &delegated_inode;
+	rd.flags	   = flags;
+	error = vfs_rename(&rd);
 exit5:
 	dput(new_dentry);
 exit4:
diff --git a/fs/namespace.c b/fs/namespace.c
index 9d33909d0f9e..062fe984a697 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -25,6 +25,7 @@
 #include <linux/proc_ns.h>
 #include <linux/magic.h>
 #include <linux/memblock.h>
+#include <linux/proc_fs.h>
 #include <linux/task_work.h>
 #include <linux/sched/task.h>
 #include <uapi/linux/mount.h>
@@ -73,6 +74,15 @@ static DECLARE_RWSEM(namespace_sem);
 static HLIST_HEAD(unmounted);	/* protected by namespace_sem */
 static LIST_HEAD(ex_mountpoints); /* protected by namespace_sem */
 
+struct mount_kattr {
+	unsigned int attr_set;
+	unsigned int attr_clr;
+	unsigned int propagation;
+	unsigned int lookup_flags;
+	bool recurse;
+	struct user_namespace *mnt_userns;
+};
+
 /* /sys/fs */
 struct kobject *fs_kobj;
 EXPORT_SYMBOL_GPL(fs_kobj);
@@ -87,6 +97,16 @@ EXPORT_SYMBOL_GPL(fs_kobj);
  */
 __cacheline_aligned_in_smp DEFINE_SEQLOCK(mount_lock);
 
+static inline void lock_mount_hash(void)
+{
+	write_seqlock(&mount_lock);
+}
+
+static inline void unlock_mount_hash(void)
+{
+	write_sequnlock(&mount_lock);
+}
+
 static inline struct hlist_head *m_hash(struct vfsmount *mnt, struct dentry *dentry)
 {
 	unsigned long tmp = ((unsigned long)mnt / L1_CACHE_BYTES);
@@ -210,6 +230,7 @@ static struct mount *alloc_vfsmnt(const char *name)
 		INIT_HLIST_NODE(&mnt->mnt_mp_list);
 		INIT_LIST_HEAD(&mnt->mnt_umounting);
 		INIT_HLIST_HEAD(&mnt->mnt_stuck_children);
+		mnt->mnt.mnt_userns = &init_user_ns;
 	}
 	return mnt;
 
@@ -459,11 +480,8 @@ void mnt_drop_write_file(struct file *file)
 }
 EXPORT_SYMBOL(mnt_drop_write_file);
 
-static int mnt_make_readonly(struct mount *mnt)
+static inline int mnt_hold_writers(struct mount *mnt)
 {
-	int ret = 0;
-
-	lock_mount_hash();
 	mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
 	/*
 	 * After storing MNT_WRITE_HOLD, we'll read the counters. This store
@@ -488,25 +506,30 @@ static int mnt_make_readonly(struct mount *mnt)
 	 * we're counting up here.
 	 */
 	if (mnt_get_writers(mnt) > 0)
-		ret = -EBUSY;
-	else
-		mnt->mnt.mnt_flags |= MNT_READONLY;
+		return -EBUSY;
+
+	return 0;
+}
+
+static inline void mnt_unhold_writers(struct mount *mnt)
+{
 	/*
 	 * MNT_READONLY must become visible before ~MNT_WRITE_HOLD, so writers
 	 * that become unheld will see MNT_READONLY.
 	 */
 	smp_wmb();
 	mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
-	unlock_mount_hash();
-	return ret;
 }
 
-static int __mnt_unmake_readonly(struct mount *mnt)
+static int mnt_make_readonly(struct mount *mnt)
 {
-	lock_mount_hash();
-	mnt->mnt.mnt_flags &= ~MNT_READONLY;
-	unlock_mount_hash();
-	return 0;
+	int ret;
+
+	ret = mnt_hold_writers(mnt);
+	if (!ret)
+		mnt->mnt.mnt_flags |= MNT_READONLY;
+	mnt_unhold_writers(mnt);
+	return ret;
 }
 
 int sb_prepare_remount_readonly(struct super_block *sb)
@@ -547,6 +570,11 @@ int sb_prepare_remount_readonly(struct super_block *sb)
 
 static void free_vfsmnt(struct mount *mnt)
 {
+	struct user_namespace *mnt_userns;
+
+	mnt_userns = mnt_user_ns(&mnt->mnt);
+	if (mnt_userns != &init_user_ns)
+		put_user_ns(mnt_userns);
 	kfree_const(mnt->mnt_devname);
 #ifdef CONFIG_SMP
 	free_percpu(mnt->mnt_pcp);
@@ -1055,6 +1083,9 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
 	mnt->mnt.mnt_flags &= ~(MNT_WRITE_HOLD|MNT_MARKED|MNT_INTERNAL);
 
 	atomic_inc(&sb->s_active);
+	mnt->mnt.mnt_userns = mnt_user_ns(&old->mnt);
+	if (mnt->mnt.mnt_userns != &init_user_ns)
+		mnt->mnt.mnt_userns = get_user_ns(mnt->mnt.mnt_userns);
 	mnt->mnt.mnt_sb = sb;
 	mnt->mnt.mnt_root = dget(root);
 	mnt->mnt_mountpoint = mnt->mnt.mnt_root;
@@ -2514,20 +2545,15 @@ static int change_mount_ro_state(struct mount *mnt, unsigned int mnt_flags)
 	if (readonly_request)
 		return mnt_make_readonly(mnt);
 
-	return __mnt_unmake_readonly(mnt);
+	mnt->mnt.mnt_flags &= ~MNT_READONLY;
+	return 0;
 }
 
-/*
- * Update the user-settable attributes on a mount.  The caller must hold
- * sb->s_umount for writing.
- */
 static void set_mount_attributes(struct mount *mnt, unsigned int mnt_flags)
 {
-	lock_mount_hash();
 	mnt_flags |= mnt->mnt.mnt_flags & ~MNT_USER_SETTABLE_MASK;
 	mnt->mnt.mnt_flags = mnt_flags;
 	touch_mnt_namespace(mnt->mnt_ns);
-	unlock_mount_hash();
 }
 
 static void mnt_warn_timestamp_expiry(struct path *mountpoint, struct vfsmount *mnt)
@@ -2572,11 +2598,17 @@ static int do_reconfigure_mnt(struct path *path, unsigned int mnt_flags)
 	if (!can_change_locked_flags(mnt, mnt_flags))
 		return -EPERM;
 
-	down_write(&sb->s_umount);
+	/*
+	 * We're only checking whether the superblock is read-only not
+	 * changing it, so only take down_read(&sb->s_umount).
+	 */
+	down_read(&sb->s_umount);
+	lock_mount_hash();
 	ret = change_mount_ro_state(mnt, mnt_flags);
 	if (ret == 0)
 		set_mount_attributes(mnt, mnt_flags);
-	up_write(&sb->s_umount);
+	unlock_mount_hash();
+	up_read(&sb->s_umount);
 
 	mnt_warn_timestamp_expiry(path, &mnt->mnt);
 
@@ -2616,8 +2648,11 @@ static int do_remount(struct path *path, int ms_flags, int sb_flags,
 		err = -EPERM;
 		if (ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) {
 			err = reconfigure_super(fc);
-			if (!err)
+			if (!err) {
+				lock_mount_hash();
 				set_mount_attributes(mnt, mnt_flags);
+				unlock_mount_hash();
+			}
 		}
 		up_write(&sb->s_umount);
 	}
@@ -3440,6 +3475,33 @@ out_type:
 	return ret;
 }
 
+#define FSMOUNT_VALID_FLAGS \
+	(MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NODEV | \
+	 MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME | MOUNT_ATTR_NODIRATIME)
+
+#define MOUNT_SETATTR_VALID_FLAGS (FSMOUNT_VALID_FLAGS | MOUNT_ATTR_IDMAP)
+
+#define MOUNT_SETATTR_PROPAGATION_FLAGS \
+	(MS_UNBINDABLE | MS_PRIVATE | MS_SLAVE | MS_SHARED)
+
+static unsigned int attr_flags_to_mnt_flags(u64 attr_flags)
+{
+	unsigned int mnt_flags = 0;
+
+	if (attr_flags & MOUNT_ATTR_RDONLY)
+		mnt_flags |= MNT_READONLY;
+	if (attr_flags & MOUNT_ATTR_NOSUID)
+		mnt_flags |= MNT_NOSUID;
+	if (attr_flags & MOUNT_ATTR_NODEV)
+		mnt_flags |= MNT_NODEV;
+	if (attr_flags & MOUNT_ATTR_NOEXEC)
+		mnt_flags |= MNT_NOEXEC;
+	if (attr_flags & MOUNT_ATTR_NODIRATIME)
+		mnt_flags |= MNT_NODIRATIME;
+
+	return mnt_flags;
+}
+
 /*
  * Create a kernel mount representation for a new, prepared superblock
  * (specified by fs_fd) and attach to an open_tree-like file descriptor.
@@ -3462,24 +3524,10 @@ SYSCALL_DEFINE3(fsmount, int, fs_fd, unsigned int, flags,
 	if ((flags & ~(FSMOUNT_CLOEXEC)) != 0)
 		return -EINVAL;
 
-	if (attr_flags & ~(MOUNT_ATTR_RDONLY |
-			   MOUNT_ATTR_NOSUID |
-			   MOUNT_ATTR_NODEV |
-			   MOUNT_ATTR_NOEXEC |
-			   MOUNT_ATTR__ATIME |
-			   MOUNT_ATTR_NODIRATIME))
+	if (attr_flags & ~FSMOUNT_VALID_FLAGS)
 		return -EINVAL;
 
-	if (attr_flags & MOUNT_ATTR_RDONLY)
-		mnt_flags |= MNT_READONLY;
-	if (attr_flags & MOUNT_ATTR_NOSUID)
-		mnt_flags |= MNT_NOSUID;
-	if (attr_flags & MOUNT_ATTR_NODEV)
-		mnt_flags |= MNT_NODEV;
-	if (attr_flags & MOUNT_ATTR_NOEXEC)
-		mnt_flags |= MNT_NOEXEC;
-	if (attr_flags & MOUNT_ATTR_NODIRATIME)
-		mnt_flags |= MNT_NODIRATIME;
+	mnt_flags = attr_flags_to_mnt_flags(attr_flags);
 
 	switch (attr_flags & MOUNT_ATTR__ATIME) {
 	case MOUNT_ATTR_STRICTATIME:
@@ -3787,6 +3835,362 @@ out0:
 	return error;
 }
 
+static unsigned int recalc_flags(struct mount_kattr *kattr, struct mount *mnt)
+{
+	unsigned int flags = mnt->mnt.mnt_flags;
+
+	/*  flags to clear */
+	flags &= ~kattr->attr_clr;
+	/* flags to raise */
+	flags |= kattr->attr_set;
+
+	return flags;
+}
+
+static int can_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
+{
+	struct vfsmount *m = &mnt->mnt;
+
+	if (!kattr->mnt_userns)
+		return 0;
+
+	/*
+	 * Once a mount has been idmapped we don't allow it to change its
+	 * mapping. It makes things simpler and callers can just create
+	 * another bind-mount they can idmap if they want to.
+	 */
+	if (mnt_user_ns(m) != &init_user_ns)
+		return -EPERM;
+
+	/* The underlying filesystem doesn't support idmapped mounts yet. */
+	if (!(m->mnt_sb->s_type->fs_flags & FS_ALLOW_IDMAP))
+		return -EINVAL;
+
+	/* We're not controlling the superblock. */
+	if (!ns_capable(m->mnt_sb->s_user_ns, CAP_SYS_ADMIN))
+		return -EPERM;
+
+	/* Mount has already been visible in the filesystem hierarchy. */
+	if (!is_anon_ns(mnt->mnt_ns))
+		return -EINVAL;
+
+	return 0;
+}
+
+static struct mount *mount_setattr_prepare(struct mount_kattr *kattr,
+					   struct mount *mnt, int *err)
+{
+	struct mount *m = mnt, *last = NULL;
+
+	if (!is_mounted(&m->mnt)) {
+		*err = -EINVAL;
+		goto out;
+	}
+
+	if (!(mnt_has_parent(m) ? check_mnt(m) : is_anon_ns(m->mnt_ns))) {
+		*err = -EINVAL;
+		goto out;
+	}
+
+	do {
+		unsigned int flags;
+
+		flags = recalc_flags(kattr, m);
+		if (!can_change_locked_flags(m, flags)) {
+			*err = -EPERM;
+			goto out;
+		}
+
+		*err = can_idmap_mount(kattr, m);
+		if (*err)
+			goto out;
+
+		last = m;
+
+		if ((kattr->attr_set & MNT_READONLY) &&
+		    !(m->mnt.mnt_flags & MNT_READONLY)) {
+			*err = mnt_hold_writers(m);
+			if (*err)
+				goto out;
+		}
+	} while (kattr->recurse && (m = next_mnt(m, mnt)));
+
+out:
+	return last;
+}
+
+static void do_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
+{
+	struct user_namespace *mnt_userns;
+
+	if (!kattr->mnt_userns)
+		return;
+
+	mnt_userns = get_user_ns(kattr->mnt_userns);
+	/* Pairs with smp_load_acquire() in mnt_user_ns(). */
+	smp_store_release(&mnt->mnt.mnt_userns, mnt_userns);
+}
+
+static void mount_setattr_commit(struct mount_kattr *kattr,
+				 struct mount *mnt, struct mount *last,
+				 int err)
+{
+	struct mount *m = mnt;
+
+	do {
+		if (!err) {
+			unsigned int flags;
+
+			do_idmap_mount(kattr, m);
+			flags = recalc_flags(kattr, m);
+			WRITE_ONCE(m->mnt.mnt_flags, flags);
+		}
+
+		/*
+		 * We either set MNT_READONLY above so make it visible
+		 * before ~MNT_WRITE_HOLD or we failed to recursively
+		 * apply mount options.
+		 */
+		if ((kattr->attr_set & MNT_READONLY) &&
+		    (m->mnt.mnt_flags & MNT_WRITE_HOLD))
+			mnt_unhold_writers(m);
+
+		if (!err && kattr->propagation)
+			change_mnt_propagation(m, kattr->propagation);
+
+		/*
+		 * On failure, only cleanup until we found the first mount
+		 * we failed to handle.
+		 */
+		if (err && m == last)
+			break;
+	} while (kattr->recurse && (m = next_mnt(m, mnt)));
+
+	if (!err)
+		touch_mnt_namespace(mnt->mnt_ns);
+}
+
+static int do_mount_setattr(struct path *path, struct mount_kattr *kattr)
+{
+	struct mount *mnt = real_mount(path->mnt), *last = NULL;
+	int err = 0;
+
+	if (path->dentry != mnt->mnt.mnt_root)
+		return -EINVAL;
+
+	if (kattr->propagation) {
+		/*
+		 * Only take namespace_lock() if we're actually changing
+		 * propagation.
+		 */
+		namespace_lock();
+		if (kattr->propagation == MS_SHARED) {
+			err = invent_group_ids(mnt, kattr->recurse);
+			if (err) {
+				namespace_unlock();
+				return err;
+			}
+		}
+	}
+
+	lock_mount_hash();
+
+	/*
+	 * Get the mount tree in a shape where we can change mount
+	 * properties without failure.
+	 */
+	last = mount_setattr_prepare(kattr, mnt, &err);
+	if (last) /* Commit all changes or revert to the old state. */
+		mount_setattr_commit(kattr, mnt, last, err);
+
+	unlock_mount_hash();
+
+	if (kattr->propagation) {
+		namespace_unlock();
+		if (err)
+			cleanup_group_ids(mnt, NULL);
+	}
+
+	return err;
+}
+
+static int build_mount_idmapped(const struct mount_attr *attr, size_t usize,
+				struct mount_kattr *kattr, unsigned int flags)
+{
+	int err = 0;
+	struct ns_common *ns;
+	struct user_namespace *mnt_userns;
+	struct file *file;
+
+	if (!((attr->attr_set | attr->attr_clr) & MOUNT_ATTR_IDMAP))
+		return 0;
+
+	/*
+	 * We currently do not support clearing an idmapped mount. If this ever
+	 * is a use-case we can revisit this but for now let's keep it simple
+	 * and not allow it.
+	 */
+	if (attr->attr_clr & MOUNT_ATTR_IDMAP)
+		return -EINVAL;
+
+	if (attr->userns_fd > INT_MAX)
+		return -EINVAL;
+
+	file = fget(attr->userns_fd);
+	if (!file)
+		return -EBADF;
+
+	if (!proc_ns_file(file)) {
+		err = -EINVAL;
+		goto out_fput;
+	}
+
+	ns = get_proc_ns(file_inode(file));
+	if (ns->ops->type != CLONE_NEWUSER) {
+		err = -EINVAL;
+		goto out_fput;
+	}
+
+	/*
+	 * The init_user_ns is used to indicate that a vfsmount is not idmapped.
+	 * This is simpler than just having to treat NULL as unmapped. Users
+	 * wanting to idmap a mount to init_user_ns can just use a namespace
+	 * with an identity mapping.
+	 */
+	mnt_userns = container_of(ns, struct user_namespace, ns);
+	if (mnt_userns == &init_user_ns) {
+		err = -EPERM;
+		goto out_fput;
+	}
+	kattr->mnt_userns = get_user_ns(mnt_userns);
+
+out_fput:
+	fput(file);
+	return err;
+}
+
+static int build_mount_kattr(const struct mount_attr *attr, size_t usize,
+			     struct mount_kattr *kattr, unsigned int flags)
+{
+	unsigned int lookup_flags = LOOKUP_AUTOMOUNT | LOOKUP_FOLLOW;
+
+	if (flags & AT_NO_AUTOMOUNT)
+		lookup_flags &= ~LOOKUP_AUTOMOUNT;
+	if (flags & AT_SYMLINK_NOFOLLOW)
+		lookup_flags &= ~LOOKUP_FOLLOW;
+	if (flags & AT_EMPTY_PATH)
+		lookup_flags |= LOOKUP_EMPTY;
+
+	*kattr = (struct mount_kattr) {
+		.lookup_flags	= lookup_flags,
+		.recurse	= !!(flags & AT_RECURSIVE),
+	};
+
+	if (attr->propagation & ~MOUNT_SETATTR_PROPAGATION_FLAGS)
+		return -EINVAL;
+	if (hweight32(attr->propagation & MOUNT_SETATTR_PROPAGATION_FLAGS) > 1)
+		return -EINVAL;
+	kattr->propagation = attr->propagation;
+
+	if ((attr->attr_set | attr->attr_clr) & ~MOUNT_SETATTR_VALID_FLAGS)
+		return -EINVAL;
+
+	kattr->attr_set = attr_flags_to_mnt_flags(attr->attr_set);
+	kattr->attr_clr = attr_flags_to_mnt_flags(attr->attr_clr);
+
+	/*
+	 * Since the MOUNT_ATTR_<atime> values are an enum, not a bitmap,
+	 * users wanting to transition to a different atime setting cannot
+	 * simply specify the atime setting in @attr_set, but must also
+	 * specify MOUNT_ATTR__ATIME in the @attr_clr field.
+	 * So ensure that MOUNT_ATTR__ATIME can't be partially set in
+	 * @attr_clr and that @attr_set can't have any atime bits set if
+	 * MOUNT_ATTR__ATIME isn't set in @attr_clr.
+	 */
+	if (attr->attr_clr & MOUNT_ATTR__ATIME) {
+		if ((attr->attr_clr & MOUNT_ATTR__ATIME) != MOUNT_ATTR__ATIME)
+			return -EINVAL;
+
+		/*
+		 * Clear all previous time settings as they are mutually
+		 * exclusive.
+		 */
+		kattr->attr_clr |= MNT_RELATIME | MNT_NOATIME;
+		switch (attr->attr_set & MOUNT_ATTR__ATIME) {
+		case MOUNT_ATTR_RELATIME:
+			kattr->attr_set |= MNT_RELATIME;
+			break;
+		case MOUNT_ATTR_NOATIME:
+			kattr->attr_set |= MNT_NOATIME;
+			break;
+		case MOUNT_ATTR_STRICTATIME:
+			break;
+		default:
+			return -EINVAL;
+		}
+	} else {
+		if (attr->attr_set & MOUNT_ATTR__ATIME)
+			return -EINVAL;
+	}
+
+	return build_mount_idmapped(attr, usize, kattr, flags);
+}
+
+static void finish_mount_kattr(struct mount_kattr *kattr)
+{
+	put_user_ns(kattr->mnt_userns);
+	kattr->mnt_userns = NULL;
+}
+
+SYSCALL_DEFINE5(mount_setattr, int, dfd, const char __user *, path,
+		unsigned int, flags, struct mount_attr __user *, uattr,
+		size_t, usize)
+{
+	int err;
+	struct path target;
+	struct mount_attr attr;
+	struct mount_kattr kattr;
+
+	BUILD_BUG_ON(sizeof(struct mount_attr) != MOUNT_ATTR_SIZE_VER0);
+
+	if (flags & ~(AT_EMPTY_PATH |
+		      AT_RECURSIVE |
+		      AT_SYMLINK_NOFOLLOW |
+		      AT_NO_AUTOMOUNT))
+		return -EINVAL;
+
+	if (unlikely(usize > PAGE_SIZE))
+		return -E2BIG;
+	if (unlikely(usize < MOUNT_ATTR_SIZE_VER0))
+		return -EINVAL;
+
+	if (!may_mount())
+		return -EPERM;
+
+	err = copy_struct_from_user(&attr, sizeof(attr), uattr, usize);
+	if (err)
+		return err;
+
+	/* Don't bother walking through the mounts if this is a nop. */
+	if (attr.attr_set == 0 &&
+	    attr.attr_clr == 0 &&
+	    attr.propagation == 0)
+		return 0;
+
+	err = build_mount_kattr(&attr, usize, &kattr, flags);
+	if (err)
+		return err;
+
+	err = user_path_at(dfd, path, kattr.lookup_flags, &target);
+	if (err)
+		return err;
+
+	err = do_mount_setattr(&target, &kattr);
+	finish_mount_kattr(&kattr);
+	path_put(&target);
+	return err;
+}
+
 static void __init init_mount_tree(void)
 {
 	struct vfsmount *mnt;
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index ef827ae193d2..19a9f434442f 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2095,8 +2095,8 @@ EXPORT_SYMBOL_GPL(nfs_instantiate);
  * that the operation succeeded on the server, but an error in the
  * reply path made it appear to have failed.
  */
-int nfs_create(struct inode *dir, struct dentry *dentry,
-		umode_t mode, bool excl)
+int nfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+	       struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct iattr attr;
 	int open_flags = excl ? O_CREAT | O_EXCL : O_CREAT;
@@ -2124,7 +2124,8 @@ EXPORT_SYMBOL_GPL(nfs_create);
  * See comments for nfs_proc_create regarding failed operations.
  */
 int
-nfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
+nfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+	  struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct iattr attr;
 	int status;
@@ -2150,7 +2151,8 @@ EXPORT_SYMBOL_GPL(nfs_mknod);
 /*
  * See comments for nfs_proc_create regarding failed operations.
  */
-int nfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+int nfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+	      struct dentry *dentry, umode_t mode)
 {
 	struct iattr attr;
 	int error;
@@ -2295,7 +2297,8 @@ EXPORT_SYMBOL_GPL(nfs_unlink);
  * now have a new file handle and can instantiate an in-core NFS inode
  * and move the raw page into its mapping.
  */
-int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+int nfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		struct dentry *dentry, const char *symname)
 {
 	struct page *page;
 	char *kaddr;
@@ -2398,9 +2401,9 @@ EXPORT_SYMBOL_GPL(nfs_link);
  * If these conditions are met, we can drop the dentries before doing
  * the rename.
  */
-int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-	       struct inode *new_dir, struct dentry *new_dentry,
-	       unsigned int flags)
+int nfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+	       struct dentry *old_dentry, struct inode *new_dir,
+	       struct dentry *new_dentry, unsigned int flags)
 {
 	struct inode *old_inode = d_inode(old_dentry);
 	struct inode *new_inode = d_inode(new_dentry);
@@ -2939,7 +2942,9 @@ static int nfs_execute_ok(struct inode *inode, int mask)
 	return ret;
 }
 
-int nfs_permission(struct inode *inode, int mask)
+int nfs_permission(struct user_namespace *mnt_userns,
+		   struct inode *inode,
+		   int mask)
 {
 	const struct cred *cred = current_cred();
 	int res = 0;
@@ -2987,7 +2992,7 @@ out_notsup:
 
 	res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
 	if (res == 0)
-		res = generic_permission(inode, mask);
+		res = generic_permission(&init_user_ns, inode, mask);
 	goto out;
 }
 EXPORT_SYMBOL_GPL(nfs_permission);
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 522aa10a1a3e..447e95974386 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -594,7 +594,8 @@ EXPORT_SYMBOL_GPL(nfs_fhget);
 #define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
 
 int
-nfs_setattr(struct dentry *dentry, struct iattr *attr)
+nfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+	    struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct nfs_fattr *fattr;
@@ -787,8 +788,8 @@ static bool nfs_need_revalidate_inode(struct inode *inode)
 	return false;
 }
 
-int nfs_getattr(const struct path *path, struct kstat *stat,
-		u32 request_mask, unsigned int query_flags)
+int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		struct kstat *stat, u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct nfs_server *server = NFS_SERVER(inode);
@@ -857,7 +858,7 @@ out_no_revalidate:
 	/* Only return attributes that were revalidated. */
 	stat->result_mask &= request_mask;
 out_no_update:
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
 	if (S_ISDIR(inode->i_mode))
 		stat->blksize = NFS_SERVER(inode)->dtsize;
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 62d3189745cd..25fb43b69e5a 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -378,14 +378,18 @@ extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
 extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
 					   struct shrink_control *sc);
 struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
-int nfs_create(struct inode *, struct dentry *, umode_t, bool);
-int nfs_mkdir(struct inode *, struct dentry *, umode_t);
+int nfs_create(struct user_namespace *, struct inode *, struct dentry *,
+	       umode_t, bool);
+int nfs_mkdir(struct user_namespace *, struct inode *, struct dentry *,
+	      umode_t);
 int nfs_rmdir(struct inode *, struct dentry *);
 int nfs_unlink(struct inode *, struct dentry *);
-int nfs_symlink(struct inode *, struct dentry *, const char *);
+int nfs_symlink(struct user_namespace *, struct inode *, struct dentry *,
+		const char *);
 int nfs_link(struct dentry *, struct inode *, struct dentry *);
-int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
-int nfs_rename(struct inode *, struct dentry *,
+int nfs_mknod(struct user_namespace *, struct inode *, struct dentry *, umode_t,
+	      dev_t);
+int nfs_rename(struct user_namespace *, struct inode *, struct dentry *,
 	       struct inode *, struct dentry *, unsigned int);
 
 /* file.c */
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 2bcbe38afe2e..93e60e921f92 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -208,20 +208,23 @@ out_fc:
 }
 
 static int
-nfs_namespace_getattr(const struct path *path, struct kstat *stat,
-			u32 request_mask, unsigned int query_flags)
+nfs_namespace_getattr(struct user_namespace *mnt_userns,
+		      const struct path *path, struct kstat *stat,
+		      u32 request_mask, unsigned int query_flags)
 {
 	if (NFS_FH(d_inode(path->dentry))->size != 0)
-		return nfs_getattr(path, stat, request_mask, query_flags);
-	generic_fillattr(d_inode(path->dentry), stat);
+		return nfs_getattr(mnt_userns, path, stat, request_mask,
+				   query_flags);
+	generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
 	return 0;
 }
 
 static int
-nfs_namespace_setattr(struct dentry *dentry, struct iattr *attr)
+nfs_namespace_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		      struct iattr *attr)
 {
 	if (NFS_FH(d_inode(dentry))->size != 0)
-		return nfs_setattr(dentry, attr);
+		return nfs_setattr(mnt_userns, dentry, attr);
 	return -EACCES;
 }
 
diff --git a/fs/nfs/nfs3_fs.h b/fs/nfs/nfs3_fs.h
index 1b950b66b3bb..c8a192802dda 100644
--- a/fs/nfs/nfs3_fs.h
+++ b/fs/nfs/nfs3_fs.h
@@ -12,7 +12,8 @@
  */
 #ifdef CONFIG_NFS_V3_ACL
 extern struct posix_acl *nfs3_get_acl(struct inode *inode, int type);
-extern int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+extern int nfs3_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+			struct posix_acl *acl, int type);
 extern int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
 		struct posix_acl *dfacl);
 extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c
index c6c863382f37..5604e807fc01 100644
--- a/fs/nfs/nfs3acl.c
+++ b/fs/nfs/nfs3acl.c
@@ -251,7 +251,8 @@ int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
 
 }
 
-int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int nfs3_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type)
 {
 	struct posix_acl *orig = acl, *dfacl = NULL, *alloc;
 	int status;
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 2f4679a62712..a07530cf673d 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7491,6 +7491,7 @@ nfs4_release_lockowner(struct nfs_server *server, struct nfs4_lock_state *lsp)
 #define XATTR_NAME_NFSV4_ACL "system.nfs4_acl"
 
 static int nfs4_xattr_set_nfs4_acl(const struct xattr_handler *handler,
+				   struct user_namespace *mnt_userns,
 				   struct dentry *unused, struct inode *inode,
 				   const char *key, const void *buf,
 				   size_t buflen, int flags)
@@ -7513,6 +7514,7 @@ static bool nfs4_xattr_list_nfs4_acl(struct dentry *dentry)
 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
 
 static int nfs4_xattr_set_nfs4_label(const struct xattr_handler *handler,
+				     struct user_namespace *mnt_userns,
 				     struct dentry *unused, struct inode *inode,
 				     const char *key, const void *buf,
 				     size_t buflen, int flags)
@@ -7563,6 +7565,7 @@ nfs4_listxattr_nfs4_label(struct inode *inode, char *list, size_t list_len)
 
 #ifdef CONFIG_NFS_V4_2
 static int nfs4_xattr_set_nfs4_user(const struct xattr_handler *handler,
+				    struct user_namespace *mnt_userns,
 				    struct dentry *unused, struct inode *inode,
 				    const char *key, const void *buf,
 				    size_t buflen, int flags)
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 7c863f2c21e0..9421dae22737 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -386,8 +386,9 @@ static struct svc_export *svc_export_update(struct svc_export *new,
 					    struct svc_export *old);
 static struct svc_export *svc_export_lookup(struct svc_export *);
 
-static int check_export(struct inode *inode, int *flags, unsigned char *uuid)
+static int check_export(struct path *path, int *flags, unsigned char *uuid)
 {
+	struct inode *inode = d_inode(path->dentry);
 
 	/*
 	 * We currently export only dirs, regular files, and (for v4
@@ -411,6 +412,7 @@ static int check_export(struct inode *inode, int *flags, unsigned char *uuid)
 	 *       or an FSID number (so NFSEXP_FSID or ->uuid is needed).
 	 * 2:  We must be able to find an inode from a filehandle.
 	 *       This means that s_export_op must be set.
+	 * 3: We must not currently be on an idmapped mount.
 	 */
 	if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
 	    !(*flags & NFSEXP_FSID) &&
@@ -425,6 +427,11 @@ static int check_export(struct inode *inode, int *flags, unsigned char *uuid)
 		return -EINVAL;
 	}
 
+	if (mnt_user_ns(path->mnt) != &init_user_ns) {
+		dprintk("exp_export: export of idmapped mounts not yet supported.\n");
+		return -EINVAL;
+	}
+
 	if (inode->i_sb->s_export_op->flags & EXPORT_OP_NOSUBTREECHK &&
 	    !(*flags & NFSEXP_NOSUBTREECHECK)) {
 		dprintk("%s: %s does not support subtree checking!\n",
@@ -653,8 +660,7 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
 				goto out4;
 		}
 
-		err = check_export(d_inode(exp.ex_path.dentry), &exp.ex_flags,
-				   exp.ex_uuid);
+		err = check_export(&exp.ex_path, &exp.ex_flags, exp.ex_uuid);
 		if (err)
 			goto out4;
 		/*
diff --git a/fs/nfsd/nfs2acl.c b/fs/nfsd/nfs2acl.c
index 7eeac5b81c20..855e17772eba 100644
--- a/fs/nfsd/nfs2acl.c
+++ b/fs/nfsd/nfs2acl.c
@@ -113,10 +113,12 @@ static __be32 nfsacld_proc_setacl(struct svc_rqst *rqstp)
 
 	fh_lock(fh);
 
-	error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
+	error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_ACCESS,
+			      argp->acl_access);
 	if (error)
 		goto out_drop_lock;
-	error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
+	error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_DEFAULT,
+			      argp->acl_default);
 	if (error)
 		goto out_drop_lock;
 
diff --git a/fs/nfsd/nfs3acl.c b/fs/nfsd/nfs3acl.c
index a568b842e9eb..9a6f18d74d14 100644
--- a/fs/nfsd/nfs3acl.c
+++ b/fs/nfsd/nfs3acl.c
@@ -103,10 +103,12 @@ static __be32 nfsd3_proc_setacl(struct svc_rqst *rqstp)
 
 	fh_lock(fh);
 
-	error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
+	error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_ACCESS,
+			      argp->acl_access);
 	if (error)
 		goto out_drop_lock;
-	error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
+	error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_DEFAULT,
+			      argp->acl_default);
 
 out_drop_lock:
 	fh_unlock(fh);
diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c
index 71292a0d6f09..eaa3a0cf38f1 100644
--- a/fs/nfsd/nfs4acl.c
+++ b/fs/nfsd/nfs4acl.c
@@ -781,12 +781,13 @@ nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
 
 	fh_lock(fhp);
 
-	host_error = set_posix_acl(inode, ACL_TYPE_ACCESS, pacl);
+	host_error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_ACCESS, pacl);
 	if (host_error < 0)
 		goto out_drop_lock;
 
 	if (S_ISDIR(inode->i_mode)) {
-		host_error = set_posix_acl(inode, ACL_TYPE_DEFAULT, dpacl);
+		host_error = set_posix_acl(&init_user_ns, inode,
+					   ACL_TYPE_DEFAULT, dpacl);
 	}
 
 out_drop_lock:
diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
index 186fa2c2c6ba..891395c6c7d3 100644
--- a/fs/nfsd/nfs4recover.c
+++ b/fs/nfsd/nfs4recover.c
@@ -233,7 +233,7 @@ nfsd4_create_clid_dir(struct nfs4_client *clp)
 		 * as well be forgiving and just succeed silently.
 		 */
 		goto out_put;
-	status = vfs_mkdir(d_inode(dir), dentry, S_IRWXU);
+	status = vfs_mkdir(&init_user_ns, d_inode(dir), dentry, S_IRWXU);
 out_put:
 	dput(dentry);
 out_unlock:
@@ -353,7 +353,7 @@ nfsd4_unlink_clid_dir(char *name, int namlen, struct nfsd_net *nn)
 	status = -ENOENT;
 	if (d_really_is_negative(dentry))
 		goto out;
-	status = vfs_rmdir(d_inode(dir), dentry);
+	status = vfs_rmdir(&init_user_ns, d_inode(dir), dentry);
 out:
 	dput(dentry);
 out_unlock:
@@ -443,7 +443,7 @@ purge_old(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
 	if (nfs4_has_reclaimed_state(name, nn))
 		goto out_free;
 
-	status = vfs_rmdir(d_inode(parent), child);
+	status = vfs_rmdir(&init_user_ns, d_inode(parent), child);
 	if (status)
 		printk("failed to remove client recovery directory %pd\n",
 				child);
diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index 4744a276058d..10b44421eace 100644
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -40,7 +40,8 @@ static int nfsd_acceptable(void *expv, struct dentry *dentry)
 		/* make sure parents give x permission to user */
 		int err;
 		parent = dget_parent(tdentry);
-		err = inode_permission(d_inode(parent), MAY_EXEC);
+		err = inode_permission(&init_user_ns,
+				       d_inode(parent), MAY_EXEC);
 		if (err < 0) {
 			dput(parent);
 			break;
diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index b2f8035f166b..a8d5449dd0e9 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -90,7 +90,7 @@ nfsd_proc_setattr(struct svc_rqst *rqstp)
 		if (delta < 0)
 			delta = -delta;
 		if (delta < MAX_TOUCH_TIME_ERROR &&
-		    setattr_prepare(fhp->fh_dentry, iap) != 0) {
+		    setattr_prepare(&init_user_ns, fhp->fh_dentry, iap) != 0) {
 			/*
 			 * Turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME.
 			 * This will cause notify_change to set these times
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index d316e11923c5..fd6be35a1642 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -448,7 +448,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 			.ia_size	= iap->ia_size,
 		};
 
-		host_err = notify_change(dentry, &size_attr, NULL);
+		host_err = notify_change(&init_user_ns, dentry, &size_attr, NULL);
 		if (host_err)
 			goto out_unlock;
 		iap->ia_valid &= ~ATTR_SIZE;
@@ -463,7 +463,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 	}
 
 	iap->ia_valid |= ATTR_CTIME;
-	host_err = notify_change(dentry, iap, NULL);
+	host_err = notify_change(&init_user_ns, dentry, iap, NULL);
 
 out_unlock:
 	fh_unlock(fhp);
@@ -499,7 +499,8 @@ int nfsd4_is_junction(struct dentry *dentry)
 		return 0;
 	if (!(inode->i_mode & S_ISVTX))
 		return 0;
-	if (vfs_getxattr(dentry, NFSD_JUNCTION_XATTR_NAME, NULL, 0) <= 0)
+	if (vfs_getxattr(&init_user_ns, dentry, NFSD_JUNCTION_XATTR_NAME,
+			 NULL, 0) <= 0)
 		return 0;
 	return 1;
 }
@@ -1254,12 +1255,12 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	host_err = 0;
 	switch (type) {
 	case S_IFREG:
-		host_err = vfs_create(dirp, dchild, iap->ia_mode, true);
+		host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
 		if (!host_err)
 			nfsd_check_ignore_resizing(iap);
 		break;
 	case S_IFDIR:
-		host_err = vfs_mkdir(dirp, dchild, iap->ia_mode);
+		host_err = vfs_mkdir(&init_user_ns, dirp, dchild, iap->ia_mode);
 		if (!host_err && unlikely(d_unhashed(dchild))) {
 			struct dentry *d;
 			d = lookup_one_len(dchild->d_name.name,
@@ -1287,7 +1288,8 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	case S_IFBLK:
 	case S_IFIFO:
 	case S_IFSOCK:
-		host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
+		host_err = vfs_mknod(&init_user_ns, dirp, dchild,
+				     iap->ia_mode, rdev);
 		break;
 	default:
 		printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
@@ -1485,7 +1487,7 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (!IS_POSIXACL(dirp))
 		iap->ia_mode &= ~current_umask();
 
-	host_err = vfs_create(dirp, dchild, iap->ia_mode, true);
+	host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
 	if (host_err < 0) {
 		fh_drop_write(fhp);
 		goto out_nfserr;
@@ -1609,7 +1611,7 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (IS_ERR(dnew))
 		goto out_nfserr;
 
-	host_err = vfs_symlink(d_inode(dentry), dnew, path);
+	host_err = vfs_symlink(&init_user_ns, d_inode(dentry), dnew, path);
 	err = nfserrno(host_err);
 	if (!err)
 		err = nfserrno(commit_metadata(fhp));
@@ -1677,7 +1679,7 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
 	err = nfserr_noent;
 	if (d_really_is_negative(dold))
 		goto out_dput;
-	host_err = vfs_link(dold, dirp, dnew, NULL);
+	host_err = vfs_link(dold, &init_user_ns, dirp, dnew, NULL);
 	if (!host_err) {
 		err = nfserrno(commit_metadata(ffhp));
 		if (!err)
@@ -1797,7 +1799,15 @@ retry:
 		close_cached = true;
 		goto out_dput_old;
 	} else {
-		host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL, 0);
+		struct renamedata rd = {
+			.old_mnt_userns	= &init_user_ns,
+			.old_dir	= fdir,
+			.old_dentry	= odentry,
+			.new_mnt_userns	= &init_user_ns,
+			.new_dir	= tdir,
+			.new_dentry	= ndentry,
+		};
+		host_err = vfs_rename(&rd);
 		if (!host_err) {
 			host_err = commit_metadata(tfhp);
 			if (!host_err)
@@ -1884,9 +1894,9 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	if (type != S_IFDIR) {
 		if (rdentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK)
 			nfsd_close_cached_files(rdentry);
-		host_err = vfs_unlink(dirp, rdentry, NULL);
+		host_err = vfs_unlink(&init_user_ns, dirp, rdentry, NULL);
 	} else {
-		host_err = vfs_rmdir(dirp, rdentry);
+		host_err = vfs_rmdir(&init_user_ns, dirp, rdentry);
 	}
 
 	if (!host_err)
@@ -2149,7 +2159,7 @@ nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
 
 	inode_lock_shared(inode);
 
-	len = vfs_getxattr(dentry, name, NULL, 0);
+	len = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0);
 
 	/*
 	 * Zero-length attribute, just return.
@@ -2176,7 +2186,7 @@ nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
 		goto out;
 	}
 
-	len = vfs_getxattr(dentry, name, buf, len);
+	len = vfs_getxattr(&init_user_ns, dentry, name, buf, len);
 	if (len <= 0) {
 		kvfree(buf);
 		buf = NULL;
@@ -2283,7 +2293,8 @@ nfsd_removexattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name)
 
 	fh_lock(fhp);
 
-	ret = __vfs_removexattr_locked(fhp->fh_dentry, name, NULL);
+	ret = __vfs_removexattr_locked(&init_user_ns, fhp->fh_dentry,
+				       name, NULL);
 
 	fh_unlock(fhp);
 	fh_drop_write(fhp);
@@ -2307,8 +2318,8 @@ nfsd_setxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
 		return nfserrno(ret);
 	fh_lock(fhp);
 
-	ret = __vfs_setxattr_locked(fhp->fh_dentry, name, buf, len, flags,
-				    NULL);
+	ret = __vfs_setxattr_locked(&init_user_ns, fhp->fh_dentry, name, buf,
+				    len, flags, NULL);
 
 	fh_unlock(fhp);
 	fh_drop_write(fhp);
@@ -2391,13 +2402,14 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
 		return 0;
 
 	/* This assumes  NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
-	err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
+	err = inode_permission(&init_user_ns, inode,
+			       acc & (MAY_READ | MAY_WRITE | MAY_EXEC));
 
 	/* Allow read access to binaries even when mode 111 */
 	if (err == -EACCES && S_ISREG(inode->i_mode) &&
 	     (acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) ||
 	      acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC)))
-		err = inode_permission(inode, MAY_EXEC);
+		err = inode_permission(&init_user_ns, inode, MAY_EXEC);
 
 	return err? nfserrno(err) : 0;
 }
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 745d371d6fea..2e8eb263cf0f 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -348,7 +348,7 @@ struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
 	/* reference count of i_bh inherits from nilfs_mdt_read_block() */
 
 	atomic64_inc(&root->inodes_count);
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode->i_ino = ino;
 	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 
@@ -805,14 +805,15 @@ void nilfs_evict_inode(struct inode *inode)
 	 */
 }
 
-int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
+int nilfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *iattr)
 {
 	struct nilfs_transaction_info ti;
 	struct inode *inode = d_inode(dentry);
 	struct super_block *sb = inode->i_sb;
 	int err;
 
-	err = setattr_prepare(dentry, iattr);
+	err = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (err)
 		return err;
 
@@ -827,7 +828,7 @@ int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
 		nilfs_truncate(inode);
 	}
 
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 	mark_inode_dirty(inode);
 
 	if (iattr->ia_valid & ATTR_MODE) {
@@ -843,7 +844,8 @@ out_err:
 	return err;
 }
 
-int nilfs_permission(struct inode *inode, int mask)
+int nilfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		     int mask)
 {
 	struct nilfs_root *root = NILFS_I(inode)->i_root;
 
@@ -851,7 +853,7 @@ int nilfs_permission(struct inode *inode, int mask)
 	    root->cno != NILFS_CPTREE_CURRENT_CNO)
 		return -EROFS; /* snapshot is not writable */
 
-	return generic_permission(inode, mask);
+	return generic_permission(&init_user_ns, inode, mask);
 }
 
 int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 07d26f61f22a..b053b40315bf 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -132,7 +132,7 @@ static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp,
 	unsigned int flags, oldflags;
 	int ret;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	if (get_user(flags, (int __user *)argp))
diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
index a6ec7961d4f5..ecace5f96a95 100644
--- a/fs/nilfs2/namei.c
+++ b/fs/nilfs2/namei.c
@@ -72,8 +72,8 @@ nilfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
  * If the create succeeds, we fill in the inode information
  * with d_instantiate().
  */
-static int nilfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-			bool excl)
+static int nilfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct inode *inode;
 	struct nilfs_transaction_info ti;
@@ -100,7 +100,8 @@ static int nilfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 }
 
 static int
-nilfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
+nilfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+	    struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct inode *inode;
 	struct nilfs_transaction_info ti;
@@ -124,8 +125,8 @@ nilfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
 	return err;
 }
 
-static int nilfs_symlink(struct inode *dir, struct dentry *dentry,
-			 const char *symname)
+static int nilfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, const char *symname)
 {
 	struct nilfs_transaction_info ti;
 	struct super_block *sb = dir->i_sb;
@@ -201,7 +202,8 @@ static int nilfs_link(struct dentry *old_dentry, struct inode *dir,
 	return err;
 }
 
-static int nilfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int nilfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode;
 	struct nilfs_transaction_info ti;
@@ -338,8 +340,9 @@ static int nilfs_rmdir(struct inode *dir, struct dentry *dentry)
 	return err;
 }
 
-static int nilfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-			struct inode *new_dir,	struct dentry *new_dentry,
+static int nilfs_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry,
 			unsigned int flags)
 {
 	struct inode *old_inode = d_inode(old_dentry);
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index f8450ee3fd06..c4a45a081ade 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -267,9 +267,11 @@ extern struct inode *nilfs_iget_for_gc(struct super_block *sb,
 extern void nilfs_update_inode(struct inode *, struct buffer_head *, int);
 extern void nilfs_truncate(struct inode *);
 extern void nilfs_evict_inode(struct inode *);
-extern int nilfs_setattr(struct dentry *, struct iattr *);
+extern int nilfs_setattr(struct user_namespace *, struct dentry *,
+			 struct iattr *);
 extern void nilfs_write_failed(struct address_space *mapping, loff_t to);
-int nilfs_permission(struct inode *inode, int mask);
+int nilfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		     int mask);
 int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh);
 extern int nilfs_inode_dirty(struct inode *);
 int nilfs_set_file_dirty(struct inode *inode, unsigned int nr_dirty);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index b78dd1f88f7c..9e0c1afac8bd 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -702,7 +702,7 @@ static int fanotify_find_path(int dfd, const char __user *filename,
 	}
 
 	/* you can only watch an inode if you have read permissions on it */
-	ret = inode_permission(path->dentry->d_inode, MAY_READ);
+	ret = path_permission(path, MAY_READ);
 	if (ret) {
 		path_put(path);
 		goto out;
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 266d17e8ecb9..c71be4fb7dc5 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -352,7 +352,7 @@ static int inotify_find_inode(const char __user *dirname, struct path *path,
 	if (error)
 		return error;
 	/* you can only watch an inode if you have read permissions on it */
-	error = inode_permission(path->dentry->d_inode, MAY_READ);
+	error = path_permission(path, MAY_READ);
 	if (error) {
 		path_put(path);
 		return error;
diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
index f7e4cbc26eaf..4435dbbc0b63 100644
--- a/fs/ntfs/inode.c
+++ b/fs/ntfs/inode.c
@@ -2848,6 +2848,7 @@ void ntfs_truncate_vfs(struct inode *vi) {
 
 /**
  * ntfs_setattr - called from notify_change() when an attribute is being changed
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @dentry:	dentry whose attributes to change
  * @attr:	structure describing the attributes and the changes
  *
@@ -2860,13 +2861,14 @@ void ntfs_truncate_vfs(struct inode *vi) {
  *
  * Called with ->i_mutex held.
  */
-int ntfs_setattr(struct dentry *dentry, struct iattr *attr)
+int ntfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *attr)
 {
 	struct inode *vi = d_inode(dentry);
 	int err;
 	unsigned int ia_valid = attr->ia_valid;
 
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err)
 		goto out;
 	/* We do not support NTFS ACLs yet. */
diff --git a/fs/ntfs/inode.h b/fs/ntfs/inode.h
index 363e4e820673..6f78ee00f57f 100644
--- a/fs/ntfs/inode.h
+++ b/fs/ntfs/inode.h
@@ -289,7 +289,8 @@ extern int ntfs_show_options(struct seq_file *sf, struct dentry *root);
 extern int ntfs_truncate(struct inode *vi);
 extern void ntfs_truncate_vfs(struct inode *vi);
 
-extern int ntfs_setattr(struct dentry *dentry, struct iattr *attr);
+extern int ntfs_setattr(struct user_namespace *mnt_userns,
+			struct dentry *dentry, struct iattr *attr);
 
 extern int __ntfs_write_inode(struct inode *vi, int sync);
 
diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c
index 7b07f5df3a29..5259badabb56 100644
--- a/fs/ocfs2/acl.c
+++ b/fs/ocfs2/acl.c
@@ -262,7 +262,8 @@ static int ocfs2_set_acl(handle_t *handle,
 	return ret;
 }
 
-int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int ocfs2_iop_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		      struct posix_acl *acl, int type)
 {
 	struct buffer_head *bh = NULL;
 	int status, had_lock;
@@ -274,7 +275,8 @@ int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 	if (type == ACL_TYPE_ACCESS && acl) {
 		umode_t mode;
 
-		status = posix_acl_update_mode(inode, &mode, &acl);
+		status = posix_acl_update_mode(&init_user_ns, inode, &mode,
+					       &acl);
 		if (status)
 			goto unlock;
 
diff --git a/fs/ocfs2/acl.h b/fs/ocfs2/acl.h
index 127b13432146..4e86450917b2 100644
--- a/fs/ocfs2/acl.h
+++ b/fs/ocfs2/acl.h
@@ -19,7 +19,8 @@ struct ocfs2_acl_entry {
 };
 
 struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type);
-int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+int ocfs2_iop_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		      struct posix_acl *acl, int type);
 extern int ocfs2_acl_chmod(struct inode *, struct buffer_head *);
 extern int ocfs2_init_acl(handle_t *, struct inode *, struct inode *,
 			  struct buffer_head *, struct buffer_head *,
diff --git a/fs/ocfs2/dlmfs/dlmfs.c b/fs/ocfs2/dlmfs/dlmfs.c
index 583820ec63e2..b2870f1a31df 100644
--- a/fs/ocfs2/dlmfs/dlmfs.c
+++ b/fs/ocfs2/dlmfs/dlmfs.c
@@ -190,17 +190,18 @@ static int dlmfs_file_release(struct inode *inode,
  * We do ->setattr() just to override size changes.  Our size is the size
  * of the LVB and nothing else.
  */
-static int dlmfs_file_setattr(struct dentry *dentry, struct iattr *attr)
+static int dlmfs_file_setattr(struct user_namespace *mnt_userns,
+			      struct dentry *dentry, struct iattr *attr)
 {
 	int error;
 	struct inode *inode = d_inode(dentry);
 
 	attr->ia_valid &= ~ATTR_SIZE;
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
@@ -329,7 +330,7 @@ static struct inode *dlmfs_get_root_inode(struct super_block *sb)
 
 	if (inode) {
 		inode->i_ino = get_next_ino();
-		inode_init_owner(inode, NULL, mode);
+		inode_init_owner(&init_user_ns, inode, NULL, mode);
 		inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
 		inc_nlink(inode);
 
@@ -352,7 +353,7 @@ static struct inode *dlmfs_get_inode(struct inode *parent,
 		return NULL;
 
 	inode->i_ino = get_next_ino();
-	inode_init_owner(inode, parent, mode);
+	inode_init_owner(&init_user_ns, inode, parent, mode);
 	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
 
 	ip = DLMFS_I(inode);
@@ -395,7 +396,8 @@ static struct inode *dlmfs_get_inode(struct inode *parent,
  * File creation. Allocate an inode, and we're done..
  */
 /* SMP-safe */
-static int dlmfs_mkdir(struct inode * dir,
+static int dlmfs_mkdir(struct user_namespace * mnt_userns,
+		       struct inode * dir,
 		       struct dentry * dentry,
 		       umode_t mode)
 {
@@ -443,7 +445,8 @@ bail:
 	return status;
 }
 
-static int dlmfs_create(struct inode *dir,
+static int dlmfs_create(struct user_namespace *mnt_userns,
+			struct inode *dir,
 			struct dentry *dentry,
 			umode_t mode,
 			bool excl)
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index df6d709d2ae3..6611c64ca0be 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1112,7 +1112,8 @@ out:
 	return ret;
 }
 
-int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
+int ocfs2_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *attr)
 {
 	int status = 0, size_change;
 	int inode_locked = 0;
@@ -1142,7 +1143,7 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 	if (!(attr->ia_valid & OCFS2_VALID_ATTRS))
 		return 0;
 
-	status = setattr_prepare(dentry, attr);
+	status = setattr_prepare(&init_user_ns, dentry, attr);
 	if (status)
 		return status;
 
@@ -1263,7 +1264,7 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 		}
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 
 	status = ocfs2_mark_inode_dirty(handle, inode, bh);
@@ -1298,8 +1299,8 @@ bail:
 	return status;
 }
 
-int ocfs2_getattr(const struct path *path, struct kstat *stat,
-		  u32 request_mask, unsigned int flags)
+int ocfs2_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		  struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct super_block *sb = path->dentry->d_sb;
@@ -1313,7 +1314,7 @@ int ocfs2_getattr(const struct path *path, struct kstat *stat,
 		goto bail;
 	}
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	/*
 	 * If there is inline data in the inode, the inode will normally not
 	 * have data blocks allocated (it may have an external xattr block).
@@ -1330,7 +1331,8 @@ bail:
 	return err;
 }
 
-int ocfs2_permission(struct inode *inode, int mask)
+int ocfs2_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		     int mask)
 {
 	int ret, had_lock;
 	struct ocfs2_lock_holder oh;
@@ -1355,7 +1357,7 @@ int ocfs2_permission(struct inode *inode, int mask)
 		dump_stack();
 	}
 
-	ret = generic_permission(inode, mask);
+	ret = generic_permission(&init_user_ns, inode, mask);
 
 	ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
 out:
diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index 4832cbceba5b..8536cec5f122 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -51,10 +51,13 @@ int ocfs2_extend_no_holes(struct inode *inode, struct buffer_head *di_bh,
 			  u64 new_i_size, u64 zero_to);
 int ocfs2_zero_extend(struct inode *inode, struct buffer_head *di_bh,
 		      loff_t zero_to);
-int ocfs2_setattr(struct dentry *dentry, struct iattr *attr);
-int ocfs2_getattr(const struct path *path, struct kstat *stat,
-		  u32 request_mask, unsigned int flags);
-int ocfs2_permission(struct inode *inode, int mask);
+int ocfs2_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *attr);
+int ocfs2_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		  struct kstat *stat, u32 request_mask, unsigned int flags);
+int ocfs2_permission(struct user_namespace *mnt_userns,
+		     struct inode *inode,
+		     int mask);
 
 int ocfs2_should_update_atime(struct inode *inode,
 			      struct vfsmount *vfsmnt);
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index 89984172fc4a..50c9b30ee9f6 100644
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c
@@ -96,7 +96,7 @@ static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags,
 	}
 
 	status = -EACCES;
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		goto bail_unlock;
 
 	if (!S_ISDIR(inode->i_mode))
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 2a237ab00453..3abdd36da2e2 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -198,7 +198,7 @@ static struct inode *ocfs2_get_init_inode(struct inode *dir, umode_t mode)
 	 * callers. */
 	if (S_ISDIR(mode))
 		set_nlink(inode, 2);
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	status = dquot_initialize(inode);
 	if (status)
 		return ERR_PTR(status);
@@ -221,7 +221,8 @@ static void ocfs2_cleanup_add_entry_failure(struct ocfs2_super *osb,
 	iput(inode);
 }
 
-static int ocfs2_mknod(struct inode *dir,
+static int ocfs2_mknod(struct user_namespace *mnt_userns,
+		       struct inode *dir,
 		       struct dentry *dentry,
 		       umode_t mode,
 		       dev_t dev)
@@ -645,7 +646,8 @@ static int ocfs2_mknod_locked(struct ocfs2_super *osb,
 	return status;
 }
 
-static int ocfs2_mkdir(struct inode *dir,
+static int ocfs2_mkdir(struct user_namespace *mnt_userns,
+		       struct inode *dir,
 		       struct dentry *dentry,
 		       umode_t mode)
 {
@@ -653,14 +655,15 @@ static int ocfs2_mkdir(struct inode *dir,
 
 	trace_ocfs2_mkdir(dir, dentry, dentry->d_name.len, dentry->d_name.name,
 			  OCFS2_I(dir)->ip_blkno, mode);
-	ret = ocfs2_mknod(dir, dentry, mode | S_IFDIR, 0);
+	ret = ocfs2_mknod(&init_user_ns, dir, dentry, mode | S_IFDIR, 0);
 	if (ret)
 		mlog_errno(ret);
 
 	return ret;
 }
 
-static int ocfs2_create(struct inode *dir,
+static int ocfs2_create(struct user_namespace *mnt_userns,
+			struct inode *dir,
 			struct dentry *dentry,
 			umode_t mode,
 			bool excl)
@@ -669,7 +672,7 @@ static int ocfs2_create(struct inode *dir,
 
 	trace_ocfs2_create(dir, dentry, dentry->d_name.len, dentry->d_name.name,
 			   (unsigned long long)OCFS2_I(dir)->ip_blkno, mode);
-	ret = ocfs2_mknod(dir, dentry, mode | S_IFREG, 0);
+	ret = ocfs2_mknod(&init_user_ns, dir, dentry, mode | S_IFREG, 0);
 	if (ret)
 		mlog_errno(ret);
 
@@ -1195,7 +1198,8 @@ static void ocfs2_double_unlock(struct inode *inode1, struct inode *inode2)
 		ocfs2_inode_unlock(inode2, 1);
 }
 
-static int ocfs2_rename(struct inode *old_dir,
+static int ocfs2_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir,
 			struct dentry *old_dentry,
 			struct inode *new_dir,
 			struct dentry *new_dentry,
@@ -1784,7 +1788,8 @@ bail:
 	return status;
 }
 
-static int ocfs2_symlink(struct inode *dir,
+static int ocfs2_symlink(struct user_namespace *mnt_userns,
+			 struct inode *dir,
 			 struct dentry *dentry,
 			 const char *symname)
 {
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 3b397fa9c9e8..c26937824be1 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -4346,7 +4346,7 @@ static inline int ocfs2_may_create(struct inode *dir, struct dentry *child)
 		return -EEXIST;
 	if (IS_DEADDIR(dir))
 		return -ENOENT;
-	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+	return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
 }
 
 /**
@@ -4400,7 +4400,7 @@ static int ocfs2_vfs_reflink(struct dentry *old_dentry, struct inode *dir,
 	 * file.
 	 */
 	if (!preserve) {
-		error = inode_permission(inode, MAY_READ);
+		error = inode_permission(&init_user_ns, inode, MAY_READ);
 		if (error)
 			return error;
 	}
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 9ccd19d8f7b1..36ae47a4aef6 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -7249,6 +7249,7 @@ static int ocfs2_xattr_security_get(const struct xattr_handler *handler,
 }
 
 static int ocfs2_xattr_security_set(const struct xattr_handler *handler,
+				    struct user_namespace *mnt_userns,
 				    struct dentry *unused, struct inode *inode,
 				    const char *name, const void *value,
 				    size_t size, int flags)
@@ -7321,6 +7322,7 @@ static int ocfs2_xattr_trusted_get(const struct xattr_handler *handler,
 }
 
 static int ocfs2_xattr_trusted_set(const struct xattr_handler *handler,
+				   struct user_namespace *mnt_userns,
 				   struct dentry *unused, struct inode *inode,
 				   const char *name, const void *value,
 				   size_t size, int flags)
@@ -7351,6 +7353,7 @@ static int ocfs2_xattr_user_get(const struct xattr_handler *handler,
 }
 
 static int ocfs2_xattr_user_set(const struct xattr_handler *handler,
+				struct user_namespace *mnt_userns,
 				struct dentry *unused, struct inode *inode,
 				const char *name, const void *value,
 				size_t size, int flags)
diff --git a/fs/omfs/dir.c b/fs/omfs/dir.c
index a0f45651f3b7..c219f91f44e9 100644
--- a/fs/omfs/dir.c
+++ b/fs/omfs/dir.c
@@ -279,13 +279,14 @@ out_free_inode:
 	return err;
 }
 
-static int omfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int omfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	return omfs_add_node(dir, dentry, mode | S_IFDIR);
 }
 
-static int omfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		bool excl)
+static int omfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
 	return omfs_add_node(dir, dentry, mode | S_IFREG);
 }
@@ -369,9 +370,9 @@ static bool omfs_fill_chain(struct inode *dir, struct dir_context *ctx,
 	return true;
 }
 
-static int omfs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		       struct inode *new_dir, struct dentry *new_dentry,
-		       unsigned int flags)
+static int omfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
 {
 	struct inode *new_inode = d_inode(new_dentry);
 	struct inode *old_inode = d_inode(old_dentry);
diff --git a/fs/omfs/file.c b/fs/omfs/file.c
index 2c7b70ee1388..11e733aab25d 100644
--- a/fs/omfs/file.c
+++ b/fs/omfs/file.c
@@ -343,12 +343,13 @@ const struct file_operations omfs_file_operations = {
 	.splice_read = generic_file_splice_read,
 };
 
-static int omfs_setattr(struct dentry *dentry, struct iattr *attr)
+static int omfs_setattr(struct user_namespace *mnt_userns,
+			struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -361,7 +362,7 @@ static int omfs_setattr(struct dentry *dentry, struct iattr *attr)
 		omfs_truncate(inode);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/fs/omfs/inode.c b/fs/omfs/inode.c
index ce93ccca8639..2a0e83236c01 100644
--- a/fs/omfs/inode.c
+++ b/fs/omfs/inode.c
@@ -48,7 +48,7 @@ struct inode *omfs_new_inode(struct inode *dir, umode_t mode)
 		goto fail;
 
 	inode->i_ino = new_block;
-	inode_init_owner(inode, NULL, mode);
+	inode_init_owner(&init_user_ns, inode, NULL, mode);
 	inode->i_mapping->a_ops = &omfs_aops;
 
 	inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
diff --git a/fs/open.c b/fs/open.c
index ca5444733acd..e53af13b5835 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -35,8 +35,8 @@
 
 #include "internal.h"
 
-int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
-	struct file *filp)
+int do_truncate(struct user_namespace *mnt_userns, struct dentry *dentry,
+		loff_t length, unsigned int time_attrs, struct file *filp)
 {
 	int ret;
 	struct iattr newattrs;
@@ -61,13 +61,14 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 
 	inode_lock(dentry->d_inode);
 	/* Note any delegations or leases have already been broken: */
-	ret = notify_change(dentry, &newattrs, NULL);
+	ret = notify_change(mnt_userns, dentry, &newattrs, NULL);
 	inode_unlock(dentry->d_inode);
 	return ret;
 }
 
 long vfs_truncate(const struct path *path, loff_t length)
 {
+	struct user_namespace *mnt_userns;
 	struct inode *inode;
 	long error;
 
@@ -83,7 +84,8 @@ long vfs_truncate(const struct path *path, loff_t length)
 	if (error)
 		goto out;
 
-	error = inode_permission(inode, MAY_WRITE);
+	mnt_userns = mnt_user_ns(path->mnt);
+	error = inode_permission(mnt_userns, inode, MAY_WRITE);
 	if (error)
 		goto mnt_drop_write_and_out;
 
@@ -107,7 +109,7 @@ long vfs_truncate(const struct path *path, loff_t length)
 	if (!error)
 		error = security_path_truncate(path);
 	if (!error)
-		error = do_truncate(path->dentry, length, 0, NULL);
+		error = do_truncate(mnt_userns, path->dentry, length, 0, NULL);
 
 put_write_and_out:
 	put_write_access(inode);
@@ -186,13 +188,13 @@ long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
 	/* Check IS_APPEND on real upper inode */
 	if (IS_APPEND(file_inode(f.file)))
 		goto out_putf;
-
 	sb_start_write(inode->i_sb);
 	error = locks_verify_truncate(inode, f.file, length);
 	if (!error)
 		error = security_path_truncate(&f.file->f_path);
 	if (!error)
-		error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, f.file);
+		error = do_truncate(file_mnt_user_ns(f.file), dentry, length,
+				    ATTR_MTIME | ATTR_CTIME, f.file);
 	sb_end_write(inode->i_sb);
 out_putf:
 	fdput(f);
@@ -436,7 +438,7 @@ retry:
 			goto out_path_release;
 	}
 
-	res = inode_permission(inode, mode | MAY_ACCESS);
+	res = inode_permission(mnt_user_ns(path.mnt), inode, mode | MAY_ACCESS);
 	/* SuS v2 requires we report a read only fs too */
 	if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
 		goto out_path_release;
@@ -492,7 +494,7 @@ retry:
 	if (error)
 		goto out;
 
-	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	error = path_permission(&path, MAY_EXEC | MAY_CHDIR);
 	if (error)
 		goto dput_and_out;
 
@@ -521,7 +523,7 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
 	if (!d_can_lookup(f.file->f_path.dentry))
 		goto out_putf;
 
-	error = inode_permission(file_inode(f.file), MAY_EXEC | MAY_CHDIR);
+	error = file_permission(f.file, MAY_EXEC | MAY_CHDIR);
 	if (!error)
 		set_fs_pwd(current->fs, &f.file->f_path);
 out_putf:
@@ -540,7 +542,7 @@ retry:
 	if (error)
 		goto out;
 
-	error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+	error = path_permission(&path, MAY_EXEC | MAY_CHDIR);
 	if (error)
 		goto dput_and_out;
 
@@ -580,7 +582,8 @@ retry_deleg:
 		goto out_unlock;
 	newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
 	newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
-	error = notify_change(path->dentry, &newattrs, &delegated_inode);
+	error = notify_change(mnt_user_ns(path->mnt), path->dentry,
+			      &newattrs, &delegated_inode);
 out_unlock:
 	inode_unlock(inode);
 	if (delegated_inode) {
@@ -641,6 +644,7 @@ SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode)
 
 int chown_common(const struct path *path, uid_t user, gid_t group)
 {
+	struct user_namespace *mnt_userns;
 	struct inode *inode = path->dentry->d_inode;
 	struct inode *delegated_inode = NULL;
 	int error;
@@ -651,6 +655,10 @@ int chown_common(const struct path *path, uid_t user, gid_t group)
 	uid = make_kuid(current_user_ns(), user);
 	gid = make_kgid(current_user_ns(), group);
 
+	mnt_userns = mnt_user_ns(path->mnt);
+	uid = kuid_from_mnt(mnt_userns, uid);
+	gid = kgid_from_mnt(mnt_userns, gid);
+
 retry_deleg:
 	newattrs.ia_valid =  ATTR_CTIME;
 	if (user != (uid_t) -1) {
@@ -671,7 +679,8 @@ retry_deleg:
 	inode_lock(inode);
 	error = security_path_chown(path, uid, gid);
 	if (!error)
-		error = notify_change(path->dentry, &newattrs, &delegated_inode);
+		error = notify_change(mnt_userns, path->dentry, &newattrs,
+				      &delegated_inode);
 	inode_unlock(inode);
 	if (delegated_inode) {
 		error = break_deleg_wait(&delegated_inode);
diff --git a/fs/orangefs/acl.c b/fs/orangefs/acl.c
index a25e6c890975..18852b9ed82b 100644
--- a/fs/orangefs/acl.c
+++ b/fs/orangefs/acl.c
@@ -116,7 +116,8 @@ out:
 	return error;
 }
 
-int orangefs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int orangefs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		     struct posix_acl *acl, int type)
 {
 	int error;
 	struct iattr iattr;
@@ -132,7 +133,8 @@ int orangefs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 		 * and "mode" to the new desired value. It is up to
 		 * us to propagate the new mode back to the server...
 		 */
-		error = posix_acl_update_mode(inode, &iattr.ia_mode, &acl);
+		error = posix_acl_update_mode(&init_user_ns, inode,
+					      &iattr.ia_mode, &acl);
 		if (error) {
 			gossip_err("%s: posix_acl_update_mode err: %d\n",
 				   __func__,
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index 48f0547d4850..5079cfafa8d7 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -855,13 +855,13 @@ again:
 		ORANGEFS_I(inode)->attr_uid = current_fsuid();
 		ORANGEFS_I(inode)->attr_gid = current_fsgid();
 	}
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 	spin_unlock(&inode->i_lock);
 	mark_inode_dirty(inode);
 
 	if (iattr->ia_valid & ATTR_MODE)
 		/* change mod on a file that has ACLs */
-		ret = posix_acl_chmod(inode, inode->i_mode);
+		ret = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
 
 	ret = 0;
 out:
@@ -871,12 +871,13 @@ out:
 /*
  * Change attributes of an object referenced by dentry.
  */
-int orangefs_setattr(struct dentry *dentry, struct iattr *iattr)
+int orangefs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		     struct iattr *iattr)
 {
 	int ret;
 	gossip_debug(GOSSIP_INODE_DEBUG, "__orangefs_setattr: called on %pd\n",
 	    dentry);
-	ret = setattr_prepare(dentry, iattr);
+	ret = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (ret)
 	        goto out;
 	ret = __orangefs_setattr(d_inode(dentry), iattr);
@@ -890,8 +891,8 @@ out:
 /*
  * Obtain attributes of an object given a dentry
  */
-int orangefs_getattr(const struct path *path, struct kstat *stat,
-		     u32 request_mask, unsigned int flags)
+int orangefs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		     struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	int ret;
 	struct inode *inode = path->dentry->d_inode;
@@ -903,7 +904,7 @@ int orangefs_getattr(const struct path *path, struct kstat *stat,
 	ret = orangefs_inode_getattr(inode,
 	    request_mask & STATX_SIZE ? ORANGEFS_GETATTR_SIZE : 0);
 	if (ret == 0) {
-		generic_fillattr(inode, stat);
+		generic_fillattr(&init_user_ns, inode, stat);
 
 		/* override block size reported to stat */
 		if (!(request_mask & STATX_SIZE))
@@ -919,7 +920,8 @@ int orangefs_getattr(const struct path *path, struct kstat *stat,
 	return ret;
 }
 
-int orangefs_permission(struct inode *inode, int mask)
+int orangefs_permission(struct user_namespace *mnt_userns,
+			struct inode *inode, int mask)
 {
 	int ret;
 
@@ -933,7 +935,7 @@ int orangefs_permission(struct inode *inode, int mask)
 	if (ret < 0)
 		return ret;
 
-	return generic_permission(inode, mask);
+	return generic_permission(&init_user_ns, inode, mask);
 }
 
 int orangefs_update_time(struct inode *inode, struct timespec64 *time, int flags)
diff --git a/fs/orangefs/namei.c b/fs/orangefs/namei.c
index 3e7cf3d0a494..600e8eee541f 100644
--- a/fs/orangefs/namei.c
+++ b/fs/orangefs/namei.c
@@ -15,7 +15,8 @@
 /*
  * Get a newly allocated inode to go with a negative dentry.
  */
-static int orangefs_create(struct inode *dir,
+static int orangefs_create(struct user_namespace *mnt_userns,
+			struct inode *dir,
 			struct dentry *dentry,
 			umode_t mode,
 			bool exclusive)
@@ -215,7 +216,8 @@ static int orangefs_unlink(struct inode *dir, struct dentry *dentry)
 	return ret;
 }
 
-static int orangefs_symlink(struct inode *dir,
+static int orangefs_symlink(struct user_namespace *mnt_userns,
+		         struct inode *dir,
 			 struct dentry *dentry,
 			 const char *symname)
 {
@@ -303,7 +305,8 @@ out:
 	return ret;
 }
 
-static int orangefs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int orangefs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode)
 {
 	struct orangefs_inode_s *parent = ORANGEFS_I(dir);
 	struct orangefs_kernel_op_s *new_op;
@@ -372,7 +375,8 @@ out:
 	return ret;
 }
 
-static int orangefs_rename(struct inode *old_dir,
+static int orangefs_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir,
 			struct dentry *old_dentry,
 			struct inode *new_dir,
 			struct dentry *new_dentry,
diff --git a/fs/orangefs/orangefs-kernel.h b/fs/orangefs/orangefs-kernel.h
index e12aeb9623d6..0e6b97682e41 100644
--- a/fs/orangefs/orangefs-kernel.h
+++ b/fs/orangefs/orangefs-kernel.h
@@ -107,7 +107,9 @@ extern int orangefs_init_acl(struct inode *inode, struct inode *dir);
 extern const struct xattr_handler *orangefs_xattr_handlers[];
 
 extern struct posix_acl *orangefs_get_acl(struct inode *inode, int type);
-extern int orangefs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+extern int orangefs_set_acl(struct user_namespace *mnt_userns,
+			    struct inode *inode, struct posix_acl *acl,
+			    int type);
 
 /*
  * orangefs data structures
@@ -359,12 +361,13 @@ struct inode *orangefs_new_inode(struct super_block *sb,
 			      struct orangefs_object_kref *ref);
 
 int __orangefs_setattr(struct inode *, struct iattr *);
-int orangefs_setattr(struct dentry *, struct iattr *);
+int orangefs_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 
-int orangefs_getattr(const struct path *path, struct kstat *stat,
-		     u32 request_mask, unsigned int flags);
+int orangefs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		     struct kstat *stat, u32 request_mask, unsigned int flags);
 
-int orangefs_permission(struct inode *inode, int mask);
+int orangefs_permission(struct user_namespace *mnt_userns,
+			struct inode *inode, int mask);
 
 int orangefs_update_time(struct inode *, struct timespec64 *, int);
 
diff --git a/fs/orangefs/xattr.c b/fs/orangefs/xattr.c
index bdc285aea360..9a5b757fbd2f 100644
--- a/fs/orangefs/xattr.c
+++ b/fs/orangefs/xattr.c
@@ -526,6 +526,7 @@ out_unlock:
 }
 
 static int orangefs_xattr_set_default(const struct xattr_handler *handler,
+				      struct user_namespace *mnt_userns,
 				      struct dentry *unused,
 				      struct inode *inode,
 				      const char *name,
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 0fed532efa68..0b2891c6c71e 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -93,9 +93,9 @@ int ovl_copy_xattr(struct super_block *sb, struct dentry *old,
 			continue; /* Discard */
 		}
 retry:
-		size = vfs_getxattr(old, name, value, value_size);
+		size = vfs_getxattr(&init_user_ns, old, name, value, value_size);
 		if (size == -ERANGE)
-			size = vfs_getxattr(old, name, NULL, 0);
+			size = vfs_getxattr(&init_user_ns, old, name, NULL, 0);
 
 		if (size < 0) {
 			error = size;
@@ -115,7 +115,7 @@ retry:
 			goto retry;
 		}
 
-		error = vfs_setxattr(new, name, value, size, 0);
+		error = vfs_setxattr(&init_user_ns, new, name, value, size, 0);
 		if (error) {
 			if (error != -EOPNOTSUPP || ovl_must_copy_xattr(name))
 				break;
@@ -236,7 +236,7 @@ static int ovl_set_size(struct dentry *upperdentry, struct kstat *stat)
 		.ia_size = stat->size,
 	};
 
-	return notify_change(upperdentry, &attr, NULL);
+	return notify_change(&init_user_ns, upperdentry, &attr, NULL);
 }
 
 static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat)
@@ -248,7 +248,7 @@ static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat)
 		.ia_mtime = stat->mtime,
 	};
 
-	return notify_change(upperdentry, &attr, NULL);
+	return notify_change(&init_user_ns, upperdentry, &attr, NULL);
 }
 
 int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
@@ -260,7 +260,7 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
 			.ia_valid = ATTR_MODE,
 			.ia_mode = stat->mode,
 		};
-		err = notify_change(upperdentry, &attr, NULL);
+		err = notify_change(&init_user_ns, upperdentry, &attr, NULL);
 	}
 	if (!err) {
 		struct iattr attr = {
@@ -268,7 +268,7 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
 			.ia_uid = stat->uid,
 			.ia_gid = stat->gid,
 		};
-		err = notify_change(upperdentry, &attr, NULL);
+		err = notify_change(&init_user_ns, upperdentry, &attr, NULL);
 	}
 	if (!err)
 		ovl_set_timestamps(upperdentry, stat);
@@ -796,7 +796,7 @@ static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value)
 	ssize_t res;
 	char *buf;
 
-	res = vfs_getxattr(dentry, name, NULL, 0);
+	res = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0);
 	if (res == -ENODATA || res == -EOPNOTSUPP)
 		res = 0;
 
@@ -805,7 +805,7 @@ static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value)
 		if (!buf)
 			return -ENOMEM;
 
-		res = vfs_getxattr(dentry, name, buf, res);
+		res = vfs_getxattr(&init_user_ns, dentry, name, buf, res);
 		if (res < 0)
 			kfree(buf);
 		else
@@ -847,8 +847,8 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
 	 * don't want that to happen for normal copy-up operation.
 	 */
 	if (capability) {
-		err = vfs_setxattr(upperpath.dentry, XATTR_NAME_CAPS,
-				   capability, cap_size, 0);
+		err = vfs_setxattr(&init_user_ns, upperpath.dentry,
+				   XATTR_NAME_CAPS, capability, cap_size, 0);
 		if (err)
 			goto out_free;
 	}
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index d1efa3a5a503..836f14b9d3a6 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -449,7 +449,7 @@ static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name,
 	if (err < 0)
 		goto out_free;
 
-	err = vfs_setxattr(upperdentry, name, buffer, size, XATTR_CREATE);
+	err = vfs_setxattr(&init_user_ns, upperdentry, name, buffer, size, XATTR_CREATE);
 out_free:
 	kfree(buffer);
 	return err;
@@ -508,7 +508,7 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
 			.ia_mode = cattr->mode,
 		};
 		inode_lock(newdentry->d_inode);
-		err = notify_change(newdentry, &attr, NULL);
+		err = notify_change(&init_user_ns, newdentry, &attr, NULL);
 		inode_unlock(newdentry->d_inode);
 		if (err)
 			goto out_cleanup;
@@ -636,7 +636,7 @@ static int ovl_create_object(struct dentry *dentry, int mode, dev_t rdev,
 	inode->i_state |= I_CREATING;
 	spin_unlock(&inode->i_lock);
 
-	inode_init_owner(inode, dentry->d_parent->d_inode, mode);
+	inode_init_owner(&init_user_ns, inode, dentry->d_parent->d_inode, mode);
 	attr.mode = inode->i_mode;
 
 	err = ovl_create_or_link(dentry, inode, &attr, false);
@@ -650,19 +650,20 @@ out:
 	return err;
 }
 
-static int ovl_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		      bool excl)
+static int ovl_create(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, bool excl)
 {
 	return ovl_create_object(dentry, (mode & 07777) | S_IFREG, 0, NULL);
 }
 
-static int ovl_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ovl_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode)
 {
 	return ovl_create_object(dentry, (mode & 07777) | S_IFDIR, 0, NULL);
 }
 
-static int ovl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
-		     dev_t rdev)
+static int ovl_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	/* Don't allow creation of "whiteout" on overlay */
 	if (S_ISCHR(mode) && rdev == WHITEOUT_DEV)
@@ -671,8 +672,8 @@ static int ovl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 	return ovl_create_object(dentry, mode, rdev, NULL);
 }
 
-static int ovl_symlink(struct inode *dir, struct dentry *dentry,
-		       const char *link)
+static int ovl_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, const char *link)
 {
 	return ovl_create_object(dentry, S_IFLNK, 0, link);
 }
@@ -821,9 +822,9 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir,
 		goto out_dput_upper;
 
 	if (is_dir)
-		err = vfs_rmdir(dir, upper);
+		err = vfs_rmdir(&init_user_ns, dir, upper);
 	else
-		err = vfs_unlink(dir, upper, NULL);
+		err = vfs_unlink(&init_user_ns, dir, upper, NULL);
 	ovl_dir_modified(dentry->d_parent, ovl_type_origin(dentry));
 
 	/*
@@ -1069,9 +1070,9 @@ static int ovl_set_redirect(struct dentry *dentry, bool samedir)
 	return err;
 }
 
-static int ovl_rename(struct inode *olddir, struct dentry *old,
-		      struct inode *newdir, struct dentry *new,
-		      unsigned int flags)
+static int ovl_rename(struct user_namespace *mnt_userns, struct inode *olddir,
+		      struct dentry *old, struct inode *newdir,
+		      struct dentry *new, unsigned int flags)
 {
 	int err;
 	struct dentry *old_upperdir;
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 077d3ad343f6..dbfb35fb0ff7 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -50,11 +50,11 @@ static struct file *ovl_open_realfile(const struct file *file,
 		acc_mode |= MAY_APPEND;
 
 	old_cred = ovl_override_creds(inode->i_sb);
-	err = inode_permission(realinode, MAY_OPEN | acc_mode);
+	err = inode_permission(&init_user_ns, realinode, MAY_OPEN | acc_mode);
 	if (err) {
 		realfile = ERR_PTR(err);
 	} else {
-		if (!inode_owner_or_capable(realinode))
+		if (!inode_owner_or_capable(&init_user_ns, realinode))
 			flags &= ~O_NOATIME;
 
 		realfile = open_with_fake_path(&file->f_path, flags, realinode,
@@ -521,7 +521,7 @@ static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,
 	long ret;
 	struct inode *inode = file_inode(file);
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		return -EACCES;
 
 	ret = mnt_want_write_file(file);
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index cf41bcb664bc..003cf83bf78a 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -14,14 +14,15 @@
 #include "overlayfs.h"
 
 
-int ovl_setattr(struct dentry *dentry, struct iattr *attr)
+int ovl_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		struct iattr *attr)
 {
 	int err;
 	bool full_copy_up = false;
 	struct dentry *upperdentry;
 	const struct cred *old_cred;
 
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err)
 		return err;
 
@@ -79,7 +80,7 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
 
 		inode_lock(upperdentry->d_inode);
 		old_cred = ovl_override_creds(dentry->d_sb);
-		err = notify_change(upperdentry, attr, NULL);
+		err = notify_change(&init_user_ns, upperdentry, attr, NULL);
 		revert_creds(old_cred);
 		if (!err)
 			ovl_copyattr(upperdentry->d_inode, dentry->d_inode);
@@ -154,8 +155,8 @@ static int ovl_map_dev_ino(struct dentry *dentry, struct kstat *stat, int fsid)
 	return 0;
 }
 
-int ovl_getattr(const struct path *path, struct kstat *stat,
-		u32 request_mask, unsigned int flags)
+int ovl_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct dentry *dentry = path->dentry;
 	enum ovl_path_type type;
@@ -277,7 +278,8 @@ out:
 	return err;
 }
 
-int ovl_permission(struct inode *inode, int mask)
+int ovl_permission(struct user_namespace *mnt_userns,
+		   struct inode *inode, int mask)
 {
 	struct inode *upperinode = ovl_inode_upper(inode);
 	struct inode *realinode = upperinode ?: ovl_inode_lower(inode);
@@ -294,7 +296,7 @@ int ovl_permission(struct inode *inode, int mask)
 	 * Check overlay inode with the creds of task and underlying inode
 	 * with creds of mounter
 	 */
-	err = generic_permission(inode, mask);
+	err = generic_permission(&init_user_ns, inode, mask);
 	if (err)
 		return err;
 
@@ -305,7 +307,7 @@ int ovl_permission(struct inode *inode, int mask)
 		/* Make sure mounter can read file for copy up later */
 		mask |= MAY_READ;
 	}
-	err = inode_permission(realinode, mask);
+	err = inode_permission(&init_user_ns, realinode, mask);
 	revert_creds(old_cred);
 
 	return err;
@@ -353,7 +355,7 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
 
 	if (!value && !upperdentry) {
 		old_cred = ovl_override_creds(dentry->d_sb);
-		err = vfs_getxattr(realdentry, name, NULL, 0);
+		err = vfs_getxattr(&init_user_ns, realdentry, name, NULL, 0);
 		revert_creds(old_cred);
 		if (err < 0)
 			goto out_drop_write;
@@ -369,10 +371,11 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
 
 	old_cred = ovl_override_creds(dentry->d_sb);
 	if (value)
-		err = vfs_setxattr(realdentry, name, value, size, flags);
+		err = vfs_setxattr(&init_user_ns, realdentry, name, value, size,
+				   flags);
 	else {
 		WARN_ON(flags != XATTR_REPLACE);
-		err = vfs_removexattr(realdentry, name);
+		err = vfs_removexattr(&init_user_ns, realdentry, name);
 	}
 	revert_creds(old_cred);
 
@@ -394,7 +397,7 @@ int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
 		ovl_i_dentry_upper(inode) ?: ovl_dentry_lower(dentry);
 
 	old_cred = ovl_override_creds(dentry->d_sb);
-	res = vfs_getxattr(realdentry, name, value, size);
+	res = vfs_getxattr(&init_user_ns, realdentry, name, value, size);
 	revert_creds(old_cred);
 	return res;
 }
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index cb4e2d60ecf9..95cff83786a5 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -123,7 +123,7 @@ static inline const char *ovl_xattr(struct ovl_fs *ofs, enum ovl_xattr ox)
 
 static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
 {
-	int err = vfs_rmdir(dir, dentry);
+	int err = vfs_rmdir(&init_user_ns, dir, dentry);
 
 	pr_debug("rmdir(%pd2) = %i\n", dentry, err);
 	return err;
@@ -131,7 +131,7 @@ static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
 
 static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
 {
-	int err = vfs_unlink(dir, dentry, NULL);
+	int err = vfs_unlink(&init_user_ns, dir, dentry, NULL);
 
 	pr_debug("unlink(%pd2) = %i\n", dentry, err);
 	return err;
@@ -140,7 +140,7 @@ static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
 static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
 			      struct dentry *new_dentry)
 {
-	int err = vfs_link(old_dentry, dir, new_dentry, NULL);
+	int err = vfs_link(old_dentry, &init_user_ns, dir, new_dentry, NULL);
 
 	pr_debug("link(%pd2, %pd2) = %i\n", old_dentry, new_dentry, err);
 	return err;
@@ -149,7 +149,7 @@ static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
 static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
 				umode_t mode)
 {
-	int err = vfs_create(dir, dentry, mode, true);
+	int err = vfs_create(&init_user_ns, dir, dentry, mode, true);
 
 	pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
 	return err;
@@ -158,7 +158,7 @@ static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
 static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
 			       umode_t mode)
 {
-	int err = vfs_mkdir(dir, dentry, mode);
+	int err = vfs_mkdir(&init_user_ns, dir, dentry, mode);
 	pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
 	return err;
 }
@@ -166,7 +166,7 @@ static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
 static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
 			       umode_t mode, dev_t dev)
 {
-	int err = vfs_mknod(dir, dentry, mode, dev);
+	int err = vfs_mknod(&init_user_ns, dir, dentry, mode, dev);
 
 	pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry, mode, dev, err);
 	return err;
@@ -175,7 +175,7 @@ static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
 static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry,
 				 const char *oldname)
 {
-	int err = vfs_symlink(dir, dentry, oldname);
+	int err = vfs_symlink(&init_user_ns, dir, dentry, oldname);
 
 	pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
 	return err;
@@ -186,7 +186,7 @@ static inline ssize_t ovl_do_getxattr(struct ovl_fs *ofs, struct dentry *dentry,
 				      size_t size)
 {
 	const char *name = ovl_xattr(ofs, ox);
-	return vfs_getxattr(dentry, name, value, size);
+	return vfs_getxattr(&init_user_ns, dentry, name, value, size);
 }
 
 static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
@@ -194,7 +194,7 @@ static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
 				  size_t size)
 {
 	const char *name = ovl_xattr(ofs, ox);
-	int err = vfs_setxattr(dentry, name, value, size, 0);
+	int err = vfs_setxattr(&init_user_ns, dentry, name, value, size, 0);
 	pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
 		 dentry, name, min((int)size, 48), value, size, err);
 	return err;
@@ -204,7 +204,7 @@ static inline int ovl_do_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
 				     enum ovl_xattr ox)
 {
 	const char *name = ovl_xattr(ofs, ox);
-	int err = vfs_removexattr(dentry, name);
+	int err = vfs_removexattr(&init_user_ns, dentry, name);
 	pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
 	return err;
 }
@@ -214,9 +214,18 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
 				unsigned int flags)
 {
 	int err;
+	struct renamedata rd = {
+		.old_mnt_userns	= &init_user_ns,
+		.old_dir 	= olddir,
+		.old_dentry 	= olddentry,
+		.new_mnt_userns	= &init_user_ns,
+		.new_dir 	= newdir,
+		.new_dentry 	= newdentry,
+		.flags 		= flags,
+	};
 
 	pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry, newdentry, flags);
-	err = vfs_rename(olddir, olddentry, newdir, newdentry, NULL, flags);
+	err = vfs_rename(&rd);
 	if (err) {
 		pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
 			 olddentry, newdentry, err);
@@ -226,14 +235,14 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
 
 static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry)
 {
-	int err = vfs_whiteout(dir, dentry);
+	int err = vfs_whiteout(&init_user_ns, dir, dentry);
 	pr_debug("whiteout(%pd2) = %i\n", dentry, err);
 	return err;
 }
 
 static inline struct dentry *ovl_do_tmpfile(struct dentry *dentry, umode_t mode)
 {
-	struct dentry *ret = vfs_tmpfile(dentry, mode, 0);
+	struct dentry *ret = vfs_tmpfile(&init_user_ns, dentry, mode, 0);
 	int err = PTR_ERR_OR_ZERO(ret);
 
 	pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err);
@@ -436,10 +445,12 @@ int ovl_set_nlink_lower(struct dentry *dentry);
 unsigned int ovl_get_nlink(struct ovl_fs *ofs, struct dentry *lowerdentry,
 			   struct dentry *upperdentry,
 			   unsigned int fallback);
-int ovl_setattr(struct dentry *dentry, struct iattr *attr);
-int ovl_getattr(const struct path *path, struct kstat *stat,
-		u32 request_mask, unsigned int flags);
-int ovl_permission(struct inode *inode, int mask);
+int ovl_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		struct iattr *attr);
+int ovl_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		struct kstat *stat, u32 request_mask, unsigned int flags);
+int ovl_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		   int mask);
 int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
 		  const void *value, size_t size, int flags);
 int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index d58b8f2bf9d0..fdd72f1a9c5e 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -803,17 +803,19 @@ retry:
 		 * allowed as upper are limited to "normal" ones, where checking
 		 * for the above two errors is sufficient.
 		 */
-		err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_DEFAULT);
+		err = vfs_removexattr(&init_user_ns, work,
+				      XATTR_NAME_POSIX_ACL_DEFAULT);
 		if (err && err != -ENODATA && err != -EOPNOTSUPP)
 			goto out_dput;
 
-		err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_ACCESS);
+		err = vfs_removexattr(&init_user_ns, work,
+				      XATTR_NAME_POSIX_ACL_ACCESS);
 		if (err && err != -ENODATA && err != -EOPNOTSUPP)
 			goto out_dput;
 
 		/* Clear any inherited mode bits */
 		inode_lock(work->d_inode);
-		err = notify_change(work, &attr, NULL);
+		err = notify_change(&init_user_ns, work, &attr, NULL);
 		inode_unlock(work->d_inode);
 		if (err)
 			goto out_dput;
@@ -865,6 +867,10 @@ static int ovl_mount_dir_noesc(const char *name, struct path *path)
 		pr_err("filesystem on '%s' not supported\n", name);
 		goto out_put;
 	}
+	if (mnt_user_ns(path->mnt) != &init_user_ns) {
+		pr_err("idmapped layers are currently not supported\n");
+		goto out_put;
+	}
 	if (!d_is_dir(path->dentry)) {
 		pr_err("'%s' not a directory\n", name);
 		goto out_put;
@@ -989,6 +995,7 @@ ovl_posix_acl_xattr_get(const struct xattr_handler *handler,
 
 static int __maybe_unused
 ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
+			struct user_namespace *mnt_userns,
 			struct dentry *dentry, struct inode *inode,
 			const char *name, const void *value,
 			size_t size, int flags)
@@ -1014,7 +1021,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
 		goto out_acl_release;
 	}
 	err = -EPERM;
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(&init_user_ns, inode))
 		goto out_acl_release;
 
 	posix_acl_release(acl);
@@ -1026,10 +1033,10 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
 	if (unlikely(inode->i_mode & S_ISGID) &&
 	    handler->flags == ACL_TYPE_ACCESS &&
 	    !in_group_p(inode->i_gid) &&
-	    !capable_wrt_inode_uidgid(inode, CAP_FSETID)) {
+	    !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID)) {
 		struct iattr iattr = { .ia_valid = ATTR_KILL_SGID };
 
-		err = ovl_setattr(dentry, &iattr);
+		err = ovl_setattr(&init_user_ns, dentry, &iattr);
 		if (err)
 			return err;
 	}
@@ -1053,6 +1060,7 @@ static int ovl_own_xattr_get(const struct xattr_handler *handler,
 }
 
 static int ovl_own_xattr_set(const struct xattr_handler *handler,
+			     struct user_namespace *mnt_userns,
 			     struct dentry *dentry, struct inode *inode,
 			     const char *name, const void *value,
 			     size_t size, int flags)
@@ -1068,6 +1076,7 @@ static int ovl_other_xattr_get(const struct xattr_handler *handler,
 }
 
 static int ovl_other_xattr_set(const struct xattr_handler *handler,
+			       struct user_namespace *mnt_userns,
 			       struct dentry *dentry, struct inode *inode,
 			       const char *name, const void *value,
 			       size_t size, int flags)
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 9826b003f1d2..7f5a01a11f97 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -479,12 +479,12 @@ struct file *ovl_path_open(struct path *path, int flags)
 		BUG();
 	}
 
-	err = inode_permission(inode, acc_mode | MAY_OPEN);
+	err = inode_permission(&init_user_ns, inode, acc_mode | MAY_OPEN);
 	if (err)
 		return ERR_PTR(err);
 
 	/* O_NOATIME is an optimization, don't fail if not permitted */
-	if (inode_owner_or_capable(inode))
+	if (inode_owner_or_capable(&init_user_ns, inode))
 		flags |= O_NOATIME;
 
 	return dentry_open(path, flags, current_cred());
diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 95882b3f5f62..f3309a7edb49 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -345,10 +345,13 @@ EXPORT_SYMBOL(posix_acl_from_mode);
  * by the acl. Returns -E... otherwise.
  */
 int
-posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
+posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		     const struct posix_acl *acl, int want)
 {
 	const struct posix_acl_entry *pa, *pe, *mask_obj;
 	int found = 0;
+	kuid_t uid;
+	kgid_t gid;
 
 	want &= MAY_READ | MAY_WRITE | MAY_EXEC;
 
@@ -356,22 +359,26 @@ posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
                 switch(pa->e_tag) {
                         case ACL_USER_OBJ:
 				/* (May have been checked already) */
-				if (uid_eq(inode->i_uid, current_fsuid()))
+				uid = i_uid_into_mnt(mnt_userns, inode);
+				if (uid_eq(uid, current_fsuid()))
                                         goto check_perm;
                                 break;
                         case ACL_USER:
-				if (uid_eq(pa->e_uid, current_fsuid()))
+				uid = kuid_into_mnt(mnt_userns, pa->e_uid);
+				if (uid_eq(uid, current_fsuid()))
                                         goto mask;
 				break;
                         case ACL_GROUP_OBJ:
-                                if (in_group_p(inode->i_gid)) {
+				gid = i_gid_into_mnt(mnt_userns, inode);
+				if (in_group_p(gid)) {
 					found = 1;
 					if ((pa->e_perm & want) == want)
 						goto mask;
                                 }
 				break;
                         case ACL_GROUP:
-				if (in_group_p(pa->e_gid)) {
+				gid = kgid_into_mnt(mnt_userns, pa->e_gid);
+				if (in_group_p(gid)) {
 					found = 1;
 					if ((pa->e_perm & want) == want)
 						goto mask;
@@ -551,8 +558,22 @@ __posix_acl_chmod(struct posix_acl **acl, gfp_t gfp, umode_t mode)
 }
 EXPORT_SYMBOL(__posix_acl_chmod);
 
+/**
+ * posix_acl_chmod - chmod a posix acl
+ *
+ * @mnt_userns:	user namespace of the mount @inode was found from
+ * @inode:	inode to check permissions on
+ * @mode:	the new mode of @inode
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ */
 int
-posix_acl_chmod(struct inode *inode, umode_t mode)
+ posix_acl_chmod(struct user_namespace *mnt_userns, struct inode *inode,
+		    umode_t mode)
 {
 	struct posix_acl *acl;
 	int ret = 0;
@@ -572,7 +593,7 @@ posix_acl_chmod(struct inode *inode, umode_t mode)
 	ret = __posix_acl_chmod(&acl, GFP_KERNEL, mode);
 	if (ret)
 		return ret;
-	ret = inode->i_op->set_acl(inode, acl, ACL_TYPE_ACCESS);
+	ret = inode->i_op->set_acl(mnt_userns, inode, acl, ACL_TYPE_ACCESS);
 	posix_acl_release(acl);
 	return ret;
 }
@@ -631,9 +652,10 @@ EXPORT_SYMBOL_GPL(posix_acl_create);
 
 /**
  * posix_acl_update_mode  -  update mode in set_acl
- * @inode: target inode
- * @mode_p: mode (pointer) for update
- * @acl: acl pointer
+ * @mnt_userns:	user namespace of the mount @inode was found from
+ * @inode:	target inode
+ * @mode_p:	mode (pointer) for update
+ * @acl:	acl pointer
  *
  * Update the file mode when setting an ACL: compute the new file permission
  * bits based on the ACL.  In addition, if the ACL is equivalent to the new
@@ -642,9 +664,16 @@ EXPORT_SYMBOL_GPL(posix_acl_create);
  * As with chmod, clear the setgid bit if the caller is not in the owning group
  * or capable of CAP_FSETID (see inode_change_ok).
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ *
  * Called from set_acl inode operations.
  */
-int posix_acl_update_mode(struct inode *inode, umode_t *mode_p,
+int posix_acl_update_mode(struct user_namespace *mnt_userns,
+			  struct inode *inode, umode_t *mode_p,
 			  struct posix_acl **acl)
 {
 	umode_t mode = inode->i_mode;
@@ -655,8 +684,8 @@ int posix_acl_update_mode(struct inode *inode, umode_t *mode_p,
 		return error;
 	if (error == 0)
 		*acl = NULL;
-	if (!in_group_p(inode->i_gid) &&
-	    !capable_wrt_inode_uidgid(inode, CAP_FSETID))
+	if (!in_group_p(i_gid_into_mnt(mnt_userns, inode)) &&
+	    !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID))
 		mode &= ~S_ISGID;
 	*mode_p = mode;
 	return 0;
@@ -668,7 +697,8 @@ EXPORT_SYMBOL(posix_acl_update_mode);
  */
 static void posix_acl_fix_xattr_userns(
 	struct user_namespace *to, struct user_namespace *from,
-	void *value, size_t size)
+	struct user_namespace *mnt_userns,
+	void *value, size_t size, bool from_user)
 {
 	struct posix_acl_xattr_header *header = value;
 	struct posix_acl_xattr_entry *entry = (void *)(header + 1), *end;
@@ -693,10 +723,18 @@ static void posix_acl_fix_xattr_userns(
 		switch(le16_to_cpu(entry->e_tag)) {
 		case ACL_USER:
 			uid = make_kuid(from, le32_to_cpu(entry->e_id));
+			if (from_user)
+				uid = kuid_from_mnt(mnt_userns, uid);
+			else
+				uid = kuid_into_mnt(mnt_userns, uid);
 			entry->e_id = cpu_to_le32(from_kuid(to, uid));
 			break;
 		case ACL_GROUP:
 			gid = make_kgid(from, le32_to_cpu(entry->e_id));
+			if (from_user)
+				gid = kgid_from_mnt(mnt_userns, gid);
+			else
+				gid = kgid_into_mnt(mnt_userns, gid);
 			entry->e_id = cpu_to_le32(from_kgid(to, gid));
 			break;
 		default:
@@ -705,20 +743,24 @@ static void posix_acl_fix_xattr_userns(
 	}
 }
 
-void posix_acl_fix_xattr_from_user(void *value, size_t size)
+void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
+				   void *value, size_t size)
 {
 	struct user_namespace *user_ns = current_user_ns();
-	if (user_ns == &init_user_ns)
+	if ((user_ns == &init_user_ns) && (mnt_userns == &init_user_ns))
 		return;
-	posix_acl_fix_xattr_userns(&init_user_ns, user_ns, value, size);
+	posix_acl_fix_xattr_userns(&init_user_ns, user_ns, mnt_userns, value,
+				   size, true);
 }
 
-void posix_acl_fix_xattr_to_user(void *value, size_t size)
+void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
+				 void *value, size_t size)
 {
 	struct user_namespace *user_ns = current_user_ns();
-	if (user_ns == &init_user_ns)
+	if ((user_ns == &init_user_ns) && (mnt_userns == &init_user_ns))
 		return;
-	posix_acl_fix_xattr_userns(user_ns, &init_user_ns, value, size);
+	posix_acl_fix_xattr_userns(user_ns, &init_user_ns, mnt_userns, value,
+				   size, false);
 }
 
 /*
@@ -858,7 +900,8 @@ posix_acl_xattr_get(const struct xattr_handler *handler,
 }
 
 int
-set_posix_acl(struct inode *inode, int type, struct posix_acl *acl)
+set_posix_acl(struct user_namespace *mnt_userns, struct inode *inode,
+	      int type, struct posix_acl *acl)
 {
 	if (!IS_POSIXACL(inode))
 		return -EOPNOTSUPP;
@@ -867,7 +910,7 @@ set_posix_acl(struct inode *inode, int type, struct posix_acl *acl)
 
 	if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
 		return acl ? -EACCES : 0;
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(mnt_userns, inode))
 		return -EPERM;
 
 	if (acl) {
@@ -875,15 +918,16 @@ set_posix_acl(struct inode *inode, int type, struct posix_acl *acl)
 		if (ret)
 			return ret;
 	}
-	return inode->i_op->set_acl(inode, acl, type);
+	return inode->i_op->set_acl(mnt_userns, inode, acl, type);
 }
 EXPORT_SYMBOL(set_posix_acl);
 
 static int
 posix_acl_xattr_set(const struct xattr_handler *handler,
-		    struct dentry *unused, struct inode *inode,
-		    const char *name, const void *value,
-		    size_t size, int flags)
+			   struct user_namespace *mnt_userns,
+			   struct dentry *unused, struct inode *inode,
+			   const char *name, const void *value, size_t size,
+			   int flags)
 {
 	struct posix_acl *acl = NULL;
 	int ret;
@@ -893,7 +937,7 @@ posix_acl_xattr_set(const struct xattr_handler *handler,
 		if (IS_ERR(acl))
 			return PTR_ERR(acl);
 	}
-	ret = set_posix_acl(inode, handler->flags, acl);
+	ret = set_posix_acl(mnt_userns, inode, handler->flags, acl);
 	posix_acl_release(acl);
 	return ret;
 }
@@ -922,12 +966,13 @@ const struct xattr_handler posix_acl_default_xattr_handler = {
 };
 EXPORT_SYMBOL_GPL(posix_acl_default_xattr_handler);
 
-int simple_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+int simple_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		   struct posix_acl *acl, int type)
 {
 	int error;
 
 	if (type == ACL_TYPE_ACCESS) {
-		error = posix_acl_update_mode(inode,
+		error = posix_acl_update_mode(mnt_userns, inode,
 				&inode->i_mode, &acl);
 		if (error)
 			return error;
diff --git a/fs/proc/base.c b/fs/proc/base.c
index b3422cda2a91..56bf14316122 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -685,7 +685,8 @@ static int proc_fd_access_allowed(struct inode *inode)
 	return allowed;
 }
 
-int proc_setattr(struct dentry *dentry, struct iattr *attr)
+int proc_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		 struct iattr *attr)
 {
 	int error;
 	struct inode *inode = d_inode(dentry);
@@ -693,11 +694,11 @@ int proc_setattr(struct dentry *dentry, struct iattr *attr)
 	if (attr->ia_valid & ATTR_MODE)
 		return -EPERM;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
@@ -726,7 +727,8 @@ static bool has_pid_permissions(struct proc_fs_info *fs_info,
 }
 
 
-static int proc_pid_permission(struct inode *inode, int mask)
+static int proc_pid_permission(struct user_namespace *mnt_userns,
+			       struct inode *inode, int mask)
 {
 	struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
 	struct task_struct *task;
@@ -751,7 +753,7 @@ static int proc_pid_permission(struct inode *inode, int mask)
 
 		return -EPERM;
 	}
-	return generic_permission(inode, mask);
+	return generic_permission(&init_user_ns, inode, mask);
 }
 
 
@@ -1927,14 +1929,14 @@ out_unlock:
 	return NULL;
 }
 
-int pid_getattr(const struct path *path, struct kstat *stat,
-		u32 request_mask, unsigned int query_flags)
+int pid_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		struct kstat *stat, u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
 	struct task_struct *task;
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 
 	stat->uid = GLOBAL_ROOT_UID;
 	stat->gid = GLOBAL_ROOT_GID;
@@ -3473,7 +3475,8 @@ int proc_pid_readdir(struct file *file, struct dir_context *ctx)
  * This function makes sure that the node is always accessible for members of
  * same thread group.
  */
-static int proc_tid_comm_permission(struct inode *inode, int mask)
+static int proc_tid_comm_permission(struct user_namespace *mnt_userns,
+				    struct inode *inode, int mask)
 {
 	bool is_same_tgroup;
 	struct task_struct *task;
@@ -3492,7 +3495,7 @@ static int proc_tid_comm_permission(struct inode *inode, int mask)
 		return 0;
 	}
 
-	return generic_permission(inode, mask);
+	return generic_permission(&init_user_ns, inode, mask);
 }
 
 static const struct inode_operations proc_tid_comm_inode_operations = {
@@ -3798,12 +3801,13 @@ static int proc_task_readdir(struct file *file, struct dir_context *ctx)
 	return 0;
 }
 
-static int proc_task_getattr(const struct path *path, struct kstat *stat,
+static int proc_task_getattr(struct user_namespace *mnt_userns,
+			     const struct path *path, struct kstat *stat,
 			     u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct task_struct *p = get_proc_task(inode);
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 
 	if (p) {
 		stat->nlink += get_nr_threads(p);
diff --git a/fs/proc/fd.c b/fs/proc/fd.c
index cb51763ed554..07fc4fad2602 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -276,12 +276,13 @@ static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
  * /proc/pid/fd needs a special permission handler so that a process can still
  * access /proc/self/fd after it has executed a setuid().
  */
-int proc_fd_permission(struct inode *inode, int mask)
+int proc_fd_permission(struct user_namespace *mnt_userns,
+		       struct inode *inode, int mask)
 {
 	struct task_struct *p;
 	int rv;
 
-	rv = generic_permission(inode, mask);
+	rv = generic_permission(&init_user_ns, inode, mask);
 	if (rv == 0)
 		return rv;
 
diff --git a/fs/proc/fd.h b/fs/proc/fd.h
index f371a602bf58..c5a921a06a0b 100644
--- a/fs/proc/fd.h
+++ b/fs/proc/fd.h
@@ -10,7 +10,8 @@ extern const struct inode_operations proc_fd_inode_operations;
 extern const struct file_operations proc_fdinfo_operations;
 extern const struct inode_operations proc_fdinfo_inode_operations;
 
-extern int proc_fd_permission(struct inode *inode, int mask);
+extern int proc_fd_permission(struct user_namespace *mnt_userns,
+			      struct inode *inode, int mask);
 
 static inline unsigned int proc_fd(struct inode *inode)
 {
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 6c0a05f55d6b..bc86aa87cc41 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -115,17 +115,18 @@ static bool pde_subdir_insert(struct proc_dir_entry *dir,
 	return true;
 }
 
-static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
+static int proc_notify_change(struct user_namespace *mnt_userns,
+			      struct dentry *dentry, struct iattr *iattr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct proc_dir_entry *de = PDE(inode);
 	int error;
 
-	error = setattr_prepare(dentry, iattr);
+	error = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (error)
 		return error;
 
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 	mark_inode_dirty(inode);
 
 	proc_set_user(de, inode->i_uid, inode->i_gid);
@@ -133,7 +134,8 @@ static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
 	return 0;
 }
 
-static int proc_getattr(const struct path *path, struct kstat *stat,
+static int proc_getattr(struct user_namespace *mnt_userns,
+			const struct path *path, struct kstat *stat,
 			u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
@@ -145,7 +147,7 @@ static int proc_getattr(const struct path *path, struct kstat *stat,
 		}
 	}
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	return 0;
 }
 
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index f60b379dcdc7..03415f3fb3a8 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -162,8 +162,10 @@ extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
  * base.c
  */
 extern const struct dentry_operations pid_dentry_operations;
-extern int pid_getattr(const struct path *, struct kstat *, u32, unsigned int);
-extern int proc_setattr(struct dentry *, struct iattr *);
+extern int pid_getattr(struct user_namespace *, const struct path *,
+		       struct kstat *, u32, unsigned int);
+extern int proc_setattr(struct user_namespace *, struct dentry *,
+			struct iattr *);
 extern void proc_pid_evict_inode(struct proc_inode *);
 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
 extern void pid_update_inode(struct task_struct *, struct inode *);
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index 18601042af99..15c2e55d2ed2 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -289,7 +289,8 @@ static struct dentry *proc_tgid_net_lookup(struct inode *dir,
 	return de;
 }
 
-static int proc_tgid_net_getattr(const struct path *path, struct kstat *stat,
+static int proc_tgid_net_getattr(struct user_namespace *mnt_userns,
+				 const struct path *path, struct kstat *stat,
 				 u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
@@ -297,7 +298,7 @@ static int proc_tgid_net_getattr(const struct path *path, struct kstat *stat,
 
 	net = get_proc_task_net(inode);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 
 	if (net != NULL) {
 		stat->nlink = net->proc_net->nlink;
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index d2018f70d1fa..656ba24c317d 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -785,7 +785,8 @@ out:
 	return 0;
 }
 
-static int proc_sys_permission(struct inode *inode, int mask)
+static int proc_sys_permission(struct user_namespace *mnt_userns,
+			       struct inode *inode, int mask)
 {
 	/*
 	 * sysctl entries that are not writeable,
@@ -813,7 +814,8 @@ static int proc_sys_permission(struct inode *inode, int mask)
 	return error;
 }
 
-static int proc_sys_setattr(struct dentry *dentry, struct iattr *attr)
+static int proc_sys_setattr(struct user_namespace *mnt_userns,
+			    struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
@@ -821,16 +823,17 @@ static int proc_sys_setattr(struct dentry *dentry, struct iattr *attr)
 	if (attr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))
 		return -EPERM;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
 
-static int proc_sys_getattr(const struct path *path, struct kstat *stat,
+static int proc_sys_getattr(struct user_namespace *mnt_userns,
+			    const struct path *path, struct kstat *stat,
 			    u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = d_inode(path->dentry);
@@ -840,7 +843,7 @@ static int proc_sys_getattr(const struct path *path, struct kstat *stat,
 	if (IS_ERR(head))
 		return PTR_ERR(head);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	if (table)
 		stat->mode = (stat->mode & S_IFMT) | table->mode;
 
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 5e444d4f9717..c7e3b1350ef8 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -308,10 +308,11 @@ void __init proc_root_init(void)
 	register_filesystem(&proc_fs_type);
 }
 
-static int proc_root_getattr(const struct path *path, struct kstat *stat,
+static int proc_root_getattr(struct user_namespace *mnt_userns,
+			     const struct path *path, struct kstat *stat,
 			     u32 request_mask, unsigned int query_flags)
 {
-	generic_fillattr(d_inode(path->dentry), stat);
+	generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
 	stat->nlink = proc_root.nlink + nr_processes();
 	return 0;
 }
diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index eafb75755fa3..392ef5162655 100644
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -79,6 +79,9 @@ static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
 		if (mnt->mnt_flags & fs_infop->flag)
 			seq_puts(m, fs_infop->str);
 	}
+
+	if (mnt_user_ns(mnt) != &init_user_ns)
+		seq_puts(m, ",idmapped");
 }
 
 static inline void mangle(struct seq_file *m, const char *s)
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
index 355523f4a4bf..ba3525ccc27e 100644
--- a/fs/ramfs/file-nommu.c
+++ b/fs/ramfs/file-nommu.c
@@ -22,7 +22,7 @@
 #include <linux/uaccess.h>
 #include "internal.h"
 
-static int ramfs_nommu_setattr(struct dentry *, struct iattr *);
+static int ramfs_nommu_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 static unsigned long ramfs_nommu_get_unmapped_area(struct file *file,
 						   unsigned long addr,
 						   unsigned long len,
@@ -158,14 +158,15 @@ static int ramfs_nommu_resize(struct inode *inode, loff_t newsize, loff_t size)
  * handle a change of attributes
  * - we're specifically interested in a change of size
  */
-static int ramfs_nommu_setattr(struct dentry *dentry, struct iattr *ia)
+static int ramfs_nommu_setattr(struct user_namespace *mnt_userns,
+			       struct dentry *dentry, struct iattr *ia)
 {
 	struct inode *inode = d_inode(dentry);
 	unsigned int old_ia_valid = ia->ia_valid;
 	int ret = 0;
 
 	/* POSIX UID/GID verification for setting inode attributes */
-	ret = setattr_prepare(dentry, ia);
+	ret = setattr_prepare(&init_user_ns, dentry, ia);
 	if (ret)
 		return ret;
 
@@ -185,7 +186,7 @@ static int ramfs_nommu_setattr(struct dentry *dentry, struct iattr *ia)
 		}
 	}
 
-	setattr_copy(inode, ia);
+	setattr_copy(&init_user_ns, inode, ia);
  out:
 	ia->ia_valid = old_ia_valid;
 	return ret;
diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c
index ee179a81b3da..3c2658c8fde0 100644
--- a/fs/ramfs/inode.c
+++ b/fs/ramfs/inode.c
@@ -67,7 +67,7 @@ struct inode *ramfs_get_inode(struct super_block *sb,
 
 	if (inode) {
 		inode->i_ino = get_next_ino();
-		inode_init_owner(inode, dir, mode);
+		inode_init_owner(&init_user_ns, inode, dir, mode);
 		inode->i_mapping->a_ops = &ramfs_aops;
 		mapping_set_gfp_mask(inode->i_mapping, GFP_HIGHUSER);
 		mapping_set_unevictable(inode->i_mapping);
@@ -101,7 +101,8 @@ struct inode *ramfs_get_inode(struct super_block *sb,
  */
 /* SMP-safe */
 static int
-ramfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+ramfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+	    struct dentry *dentry, umode_t mode, dev_t dev)
 {
 	struct inode * inode = ramfs_get_inode(dir->i_sb, dir, mode, dev);
 	int error = -ENOSPC;
@@ -115,20 +116,23 @@ ramfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
 	return error;
 }
 
-static int ramfs_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
+static int ramfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
-	int retval = ramfs_mknod(dir, dentry, mode | S_IFDIR, 0);
+	int retval = ramfs_mknod(&init_user_ns, dir, dentry, mode | S_IFDIR, 0);
 	if (!retval)
 		inc_nlink(dir);
 	return retval;
 }
 
-static int ramfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
+static int ramfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
-	return ramfs_mknod(dir, dentry, mode | S_IFREG, 0);
+	return ramfs_mknod(&init_user_ns, dir, dentry, mode | S_IFREG, 0);
 }
 
-static int ramfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
+static int ramfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, const char *symname)
 {
 	struct inode *inode;
 	int error = -ENOSPC;
diff --git a/fs/reiserfs/acl.h b/fs/reiserfs/acl.h
index 0c1c847f992f..fd58618da360 100644
--- a/fs/reiserfs/acl.h
+++ b/fs/reiserfs/acl.h
@@ -49,7 +49,8 @@ static inline int reiserfs_acl_count(size_t size)
 
 #ifdef CONFIG_REISERFS_FS_POSIX_ACL
 struct posix_acl *reiserfs_get_acl(struct inode *inode, int type);
-int reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+int reiserfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		     struct posix_acl *acl, int type);
 int reiserfs_acl_chmod(struct inode *inode);
 int reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
 				 struct inode *dir, struct dentry *dentry,
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index c76d563dec0e..780bb90c1804 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -3282,13 +3282,14 @@ static ssize_t reiserfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 	return ret;
 }
 
-int reiserfs_setattr(struct dentry *dentry, struct iattr *attr)
+int reiserfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		     struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	unsigned int ia_valid;
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -3413,7 +3414,7 @@ int reiserfs_setattr(struct dentry *dentry, struct iattr *attr)
 	}
 
 	if (!error) {
-		setattr_copy(inode, attr);
+		setattr_copy(&init_user_ns, inode, attr);
 		mark_inode_dirty(inode);
 	}
 
diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c
index adb21bea3d60..4f1cbd930179 100644
--- a/fs/reiserfs/ioctl.c
+++ b/fs/reiserfs/ioctl.c
@@ -59,7 +59,7 @@ long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 			if (err)
 				break;
 
-			if (!inode_owner_or_capable(inode)) {
+			if (!inode_owner_or_capable(&init_user_ns, inode)) {
 				err = -EPERM;
 				goto setflags_out;
 			}
@@ -101,7 +101,7 @@ setflags_out:
 		err = put_user(inode->i_generation, (int __user *)arg);
 		break;
 	case REISERFS_IOC_SETVERSION:
-		if (!inode_owner_or_capable(inode)) {
+		if (!inode_owner_or_capable(&init_user_ns, inode)) {
 			err = -EPERM;
 			break;
 		}
diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
index 1594687582f0..e6eb05e2b2f1 100644
--- a/fs/reiserfs/namei.c
+++ b/fs/reiserfs/namei.c
@@ -615,12 +615,12 @@ static int new_inode_init(struct inode *inode, struct inode *dir, umode_t mode)
 	 * the quota init calls have to know who to charge the quota to, so
 	 * we have to set uid and gid here
 	 */
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	return dquot_initialize(inode);
 }
 
-static int reiserfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-			   bool excl)
+static int reiserfs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			   struct dentry *dentry, umode_t mode, bool excl)
 {
 	int retval;
 	struct inode *inode;
@@ -698,8 +698,8 @@ out_failed:
 	return retval;
 }
 
-static int reiserfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
-			  dev_t rdev)
+static int reiserfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	int retval;
 	struct inode *inode;
@@ -781,7 +781,8 @@ out_failed:
 	return retval;
 }
 
-static int reiserfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int reiserfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode)
 {
 	int retval;
 	struct inode *inode;
@@ -1094,8 +1095,9 @@ out_unlink:
 	return retval;
 }
 
-static int reiserfs_symlink(struct inode *parent_dir,
-			    struct dentry *dentry, const char *symname)
+static int reiserfs_symlink(struct user_namespace *mnt_userns,
+			    struct inode *parent_dir, struct dentry *dentry,
+			    const char *symname)
 {
 	int retval;
 	struct inode *inode;
@@ -1304,7 +1306,8 @@ static void set_ino_in_dir_entry(struct reiserfs_dir_entry *de,
  * one path. If it holds 2 or more, it can get into endless waiting in
  * get_empty_nodes or its clones
  */
-static int reiserfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+static int reiserfs_rename(struct user_namespace *mnt_userns,
+			   struct inode *old_dir, struct dentry *old_dentry,
 			   struct inode *new_dir, struct dentry *new_dentry,
 			   unsigned int flags)
 {
diff --git a/fs/reiserfs/reiserfs.h b/fs/reiserfs/reiserfs.h
index f69871516167..0ca2ac62e534 100644
--- a/fs/reiserfs/reiserfs.h
+++ b/fs/reiserfs/reiserfs.h
@@ -3102,7 +3102,8 @@ static inline void reiserfs_update_sd(struct reiserfs_transaction_handle *th,
 }
 
 void sd_attrs_to_i_attrs(__u16 sd_attrs, struct inode *inode);
-int reiserfs_setattr(struct dentry *dentry, struct iattr *attr);
+int reiserfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		     struct iattr *attr);
 
 int __reiserfs_write_begin(struct page *page, unsigned from, unsigned len);
 
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index fe63a7c3e0da..bd073836e141 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -66,14 +66,14 @@
 static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
 {
 	BUG_ON(!inode_is_locked(dir));
-	return dir->i_op->create(dir, dentry, mode, true);
+	return dir->i_op->create(&init_user_ns, dir, dentry, mode, true);
 }
 #endif
 
 static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 {
 	BUG_ON(!inode_is_locked(dir));
-	return dir->i_op->mkdir(dir, dentry, mode);
+	return dir->i_op->mkdir(&init_user_ns, dir, dentry, mode);
 }
 
 /*
@@ -352,7 +352,7 @@ static int chown_one_xattr(struct dentry *dentry, void *data)
 	 * ATTR_MODE is set.
 	 */
 	attrs->ia_valid &= (ATTR_UID|ATTR_GID);
-	err = reiserfs_setattr(dentry, attrs);
+	err = reiserfs_setattr(&init_user_ns, dentry, attrs);
 	attrs->ia_valid = ia_valid;
 
 	return err;
@@ -604,7 +604,7 @@ reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
 		inode_lock_nested(d_inode(dentry), I_MUTEX_XATTR);
 		inode_dio_wait(d_inode(dentry));
 
-		err = reiserfs_setattr(dentry, &newattrs);
+		err = reiserfs_setattr(&init_user_ns, dentry, &newattrs);
 		inode_unlock(d_inode(dentry));
 	} else
 		update_ctime(inode);
@@ -948,7 +948,8 @@ static int xattr_mount_check(struct super_block *s)
 	return 0;
 }
 
-int reiserfs_permission(struct inode *inode, int mask)
+int reiserfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
+			int mask)
 {
 	/*
 	 * We don't do permission checks on the internal objects.
@@ -957,7 +958,7 @@ int reiserfs_permission(struct inode *inode, int mask)
 	if (IS_PRIVATE(inode))
 		return 0;
 
-	return generic_permission(inode, mask);
+	return generic_permission(&init_user_ns, inode, mask);
 }
 
 static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
diff --git a/fs/reiserfs/xattr.h b/fs/reiserfs/xattr.h
index c764352447ba..9b3b06da568c 100644
--- a/fs/reiserfs/xattr.h
+++ b/fs/reiserfs/xattr.h
@@ -16,7 +16,8 @@ int reiserfs_xattr_init(struct super_block *sb, int mount_flags);
 int reiserfs_lookup_privroot(struct super_block *sb);
 int reiserfs_delete_xattrs(struct inode *inode);
 int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs);
-int reiserfs_permission(struct inode *inode, int mask);
+int reiserfs_permission(struct user_namespace *mnt_userns,
+			struct inode *inode, int mask);
 
 #ifdef CONFIG_REISERFS_FS_XATTR
 #define has_xattr_dir(inode) (REISERFS_I(inode)->i_flags & i_has_xattr_dir)
diff --git a/fs/reiserfs/xattr_acl.c b/fs/reiserfs/xattr_acl.c
index ccd40df6eb45..a9547144a099 100644
--- a/fs/reiserfs/xattr_acl.c
+++ b/fs/reiserfs/xattr_acl.c
@@ -18,7 +18,8 @@ static int __reiserfs_set_acl(struct reiserfs_transaction_handle *th,
 
 
 int
-reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+reiserfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		 struct posix_acl *acl, int type)
 {
 	int error, error2;
 	struct reiserfs_transaction_handle th;
@@ -40,7 +41,8 @@ reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 	reiserfs_write_unlock(inode->i_sb);
 	if (error == 0) {
 		if (type == ACL_TYPE_ACCESS && acl) {
-			error = posix_acl_update_mode(inode, &mode, &acl);
+			error = posix_acl_update_mode(&init_user_ns, inode,
+						      &mode, &acl);
 			if (error)
 				goto unlock;
 			update_mode = 1;
@@ -399,5 +401,5 @@ int reiserfs_acl_chmod(struct inode *inode)
 	    !reiserfs_posixacl(inode->i_sb))
 		return 0;
 
-	return posix_acl_chmod(inode, inode->i_mode);
+	return posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
 }
diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
index 20be9a0e5870..8965c8e5e172 100644
--- a/fs/reiserfs/xattr_security.c
+++ b/fs/reiserfs/xattr_security.c
@@ -21,7 +21,8 @@ security_get(const struct xattr_handler *handler, struct dentry *unused,
 }
 
 static int
-security_set(const struct xattr_handler *handler, struct dentry *unused,
+security_set(const struct xattr_handler *handler,
+	     struct user_namespace *mnt_userns, struct dentry *unused,
 	     struct inode *inode, const char *name, const void *buffer,
 	     size_t size, int flags)
 {
diff --git a/fs/reiserfs/xattr_trusted.c b/fs/reiserfs/xattr_trusted.c
index 5ed48da3d02b..d853cea2afcd 100644
--- a/fs/reiserfs/xattr_trusted.c
+++ b/fs/reiserfs/xattr_trusted.c
@@ -20,7 +20,8 @@ trusted_get(const struct xattr_handler *handler, struct dentry *unused,
 }
 
 static int
-trusted_set(const struct xattr_handler *handler, struct dentry *unused,
+trusted_set(const struct xattr_handler *handler,
+	    struct user_namespace *mnt_userns, struct dentry *unused,
 	    struct inode *inode, const char *name, const void *buffer,
 	    size_t size, int flags)
 {
diff --git a/fs/reiserfs/xattr_user.c b/fs/reiserfs/xattr_user.c
index a573ca45bacc..65d9cd10a5ea 100644
--- a/fs/reiserfs/xattr_user.c
+++ b/fs/reiserfs/xattr_user.c
@@ -18,7 +18,8 @@ user_get(const struct xattr_handler *handler, struct dentry *unused,
 }
 
 static int
-user_set(const struct xattr_handler *handler, struct dentry *unused,
+user_set(const struct xattr_handler *handler, struct user_namespace *mnt_userns,
+	 struct dentry *unused,
 	 struct inode *inode, const char *name, const void *buffer,
 	 size_t size, int flags)
 {
diff --git a/fs/remap_range.c b/fs/remap_range.c
index 77dba3a49e65..e4a5fdd7ad7b 100644
--- a/fs/remap_range.c
+++ b/fs/remap_range.c
@@ -432,13 +432,16 @@ EXPORT_SYMBOL(vfs_clone_file_range);
 /* Check whether we are allowed to dedupe the destination file */
 static bool allow_file_dedupe(struct file *file)
 {
+	struct user_namespace *mnt_userns = file_mnt_user_ns(file);
+	struct inode *inode = file_inode(file);
+
 	if (capable(CAP_SYS_ADMIN))
 		return true;
 	if (file->f_mode & FMODE_WRITE)
 		return true;
-	if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
+	if (uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode)))
 		return true;
-	if (!inode_permission(file_inode(file), MAY_WRITE))
+	if (!inode_permission(mnt_userns, inode, MAY_WRITE))
 		return true;
 	return false;
 }
diff --git a/fs/stat.c b/fs/stat.c
index dacecdda2e79..fbc171d038aa 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -26,21 +26,29 @@
 
 /**
  * generic_fillattr - Fill in the basic attributes from the inode struct
- * @inode: Inode to use as the source
- * @stat: Where to fill in the attributes
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @inode:	Inode to use as the source
+ * @stat:	Where to fill in the attributes
  *
  * Fill in the basic attributes in the kstat structure from data that's to be
  * found on the VFS inode structure.  This is the default if no getattr inode
  * operation is supplied.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before filling in the
+ * uid and gid filds. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
  */
-void generic_fillattr(struct inode *inode, struct kstat *stat)
+void generic_fillattr(struct user_namespace *mnt_userns, struct inode *inode,
+		      struct kstat *stat)
 {
 	stat->dev = inode->i_sb->s_dev;
 	stat->ino = inode->i_ino;
 	stat->mode = inode->i_mode;
 	stat->nlink = inode->i_nlink;
-	stat->uid = inode->i_uid;
-	stat->gid = inode->i_gid;
+	stat->uid = i_uid_into_mnt(mnt_userns, inode);
+	stat->gid = i_gid_into_mnt(mnt_userns, inode);
 	stat->rdev = inode->i_rdev;
 	stat->size = i_size_read(inode);
 	stat->atime = inode->i_atime;
@@ -67,6 +75,7 @@ EXPORT_SYMBOL(generic_fillattr);
 int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
 		      u32 request_mask, unsigned int query_flags)
 {
+	struct user_namespace *mnt_userns;
 	struct inode *inode = d_backing_inode(path->dentry);
 
 	memset(stat, 0, sizeof(*stat));
@@ -83,11 +92,12 @@ int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
 	if (IS_DAX(inode))
 		stat->attributes |= STATX_ATTR_DAX;
 
+	mnt_userns = mnt_user_ns(path->mnt);
 	if (inode->i_op->getattr)
-		return inode->i_op->getattr(path, stat, request_mask,
-					    query_flags);
+		return inode->i_op->getattr(mnt_userns, path, stat,
+					    request_mask, query_flags);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(mnt_userns, inode, stat);
 	return 0;
 }
 EXPORT_SYMBOL(vfs_getattr_nosec);
diff --git a/fs/sysv/file.c b/fs/sysv/file.c
index 45fc79a18594..90e00124ea07 100644
--- a/fs/sysv/file.c
+++ b/fs/sysv/file.c
@@ -29,12 +29,13 @@ const struct file_operations sysv_file_operations = {
 	.splice_read	= generic_file_splice_read,
 };
 
-static int sysv_setattr(struct dentry *dentry, struct iattr *attr)
+static int sysv_setattr(struct user_namespace *mnt_userns,
+			struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -47,7 +48,7 @@ static int sysv_setattr(struct dentry *dentry, struct iattr *attr)
 		sysv_truncate(inode);
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/fs/sysv/ialloc.c b/fs/sysv/ialloc.c
index 6c9801986af6..50df794a3c1f 100644
--- a/fs/sysv/ialloc.c
+++ b/fs/sysv/ialloc.c
@@ -163,7 +163,7 @@ struct inode * sysv_new_inode(const struct inode * dir, umode_t mode)
 	*sbi->s_sb_fic_count = cpu_to_fs16(sbi, count);
 	fs16_add(sbi, sbi->s_sb_total_free_inodes, -1);
 	dirty_sb(sb);
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode->i_ino = fs16_to_cpu(sbi, ino);
 	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 	inode->i_blocks = 0;
diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c
index bcb67b0cabe7..8b2e99b7bc9f 100644
--- a/fs/sysv/itree.c
+++ b/fs/sysv/itree.c
@@ -441,11 +441,11 @@ static unsigned sysv_nblocks(struct super_block *s, loff_t size)
 	return blocks;
 }
 
-int sysv_getattr(const struct path *path, struct kstat *stat,
-		 u32 request_mask, unsigned int flags)
+int sysv_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		 struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	struct super_block *s = path->dentry->d_sb;
-	generic_fillattr(d_inode(path->dentry), stat);
+	generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
 	stat->blocks = (s->s_blocksize / 512) * sysv_nblocks(s, stat->size);
 	stat->blksize = s->s_blocksize;
 	return 0;
diff --git a/fs/sysv/namei.c b/fs/sysv/namei.c
index ea2414b385ec..b2e6abc06a2d 100644
--- a/fs/sysv/namei.c
+++ b/fs/sysv/namei.c
@@ -41,7 +41,8 @@ static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry, un
 	return d_splice_alias(inode, dentry);
 }
 
-static int sysv_mknod(struct inode * dir, struct dentry * dentry, umode_t mode, dev_t rdev)
+static int sysv_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct inode * inode;
 	int err;
@@ -60,13 +61,14 @@ static int sysv_mknod(struct inode * dir, struct dentry * dentry, umode_t mode,
 	return err;
 }
 
-static int sysv_create(struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
+static int sysv_create(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl)
 {
-	return sysv_mknod(dir, dentry, mode, 0);
+	return sysv_mknod(&init_user_ns, dir, dentry, mode, 0);
 }
 
-static int sysv_symlink(struct inode * dir, struct dentry * dentry, 
-	const char * symname)
+static int sysv_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, const char *symname)
 {
 	int err = -ENAMETOOLONG;
 	int l = strlen(symname)+1;
@@ -108,7 +110,8 @@ static int sysv_link(struct dentry * old_dentry, struct inode * dir,
 	return add_nondir(dentry, inode);
 }
 
-static int sysv_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
+static int sysv_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode)
 {
 	struct inode * inode;
 	int err;
@@ -186,9 +189,9 @@ static int sysv_rmdir(struct inode * dir, struct dentry * dentry)
  * Anybody can rename anything with this: the permission checks are left to the
  * higher-level routines.
  */
-static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
-		       struct inode * new_dir, struct dentry * new_dentry,
-		       unsigned int flags)
+static int sysv_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags)
 {
 	struct inode * old_inode = d_inode(old_dentry);
 	struct inode * new_inode = d_inode(new_dentry);
diff --git a/fs/sysv/sysv.h b/fs/sysv/sysv.h
index 1cff585526b1..99ddf033da4f 100644
--- a/fs/sysv/sysv.h
+++ b/fs/sysv/sysv.h
@@ -141,7 +141,8 @@ extern struct inode *sysv_iget(struct super_block *, unsigned int);
 extern int sysv_write_inode(struct inode *, struct writeback_control *wbc);
 extern int sysv_sync_inode(struct inode *);
 extern void sysv_set_inode(struct inode *, dev_t);
-extern int sysv_getattr(const struct path *, struct kstat *, u32, unsigned int);
+extern int sysv_getattr(struct user_namespace *, const struct path *,
+			struct kstat *, u32, unsigned int);
 extern int sysv_init_icache(void);
 extern void sysv_destroy_icache(void);
 
diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
index 0ee8c6dfb036..4b83cbded559 100644
--- a/fs/tracefs/inode.c
+++ b/fs/tracefs/inode.c
@@ -67,7 +67,9 @@ static char *get_dname(struct dentry *dentry)
 	return name;
 }
 
-static int tracefs_syscall_mkdir(struct inode *inode, struct dentry *dentry, umode_t mode)
+static int tracefs_syscall_mkdir(struct user_namespace *mnt_userns,
+				 struct inode *inode, struct dentry *dentry,
+				 umode_t mode)
 {
 	char *name;
 	int ret;
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 9a6b8660425a..d9d8d7794eff 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -94,7 +94,7 @@ struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir,
 	 */
 	inode->i_flags |= S_NOCMTIME;
 
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode->i_mtime = inode->i_atime = inode->i_ctime =
 			 current_time(inode);
 	inode->i_mapping->nrpages = 0;
@@ -280,8 +280,8 @@ static int ubifs_prepare_create(struct inode *dir, struct dentry *dentry,
 	return fscrypt_setup_filename(dir, &dentry->d_name, 0, nm);
 }
 
-static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-			bool excl)
+static int ubifs_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct inode *inode;
 	struct ubifs_info *c = dir->i_sb->s_fs_info;
@@ -441,8 +441,8 @@ out_budg:
 	return err;
 }
 
-static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
-			 umode_t mode)
+static int ubifs_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, umode_t mode)
 {
 	return do_tmpfile(dir, dentry, mode, NULL);
 }
@@ -942,7 +942,8 @@ out_fname:
 	return err;
 }
 
-static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ubifs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode;
 	struct ubifs_inode *dir_ui = ubifs_inode(dir);
@@ -1013,8 +1014,8 @@ out_budg:
 	return err;
 }
 
-static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
-		       umode_t mode, dev_t rdev)
+static int ubifs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct inode *inode;
 	struct ubifs_inode *ui;
@@ -1102,8 +1103,8 @@ out_budg:
 	return err;
 }
 
-static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
-			 const char *symname)
+static int ubifs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, const char *symname)
 {
 	struct inode *inode;
 	struct ubifs_inode *ui;
@@ -1542,7 +1543,8 @@ static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
 	return err;
 }
 
-static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
+static int ubifs_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir, struct dentry *old_dentry,
 			struct inode *new_dir, struct dentry *new_dentry,
 			unsigned int flags)
 {
@@ -1566,8 +1568,8 @@ static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	return do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
 }
 
-int ubifs_getattr(const struct path *path, struct kstat *stat,
-		  u32 request_mask, unsigned int flags)
+int ubifs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		  struct kstat *stat, u32 request_mask, unsigned int flags)
 {
 	loff_t size;
 	struct inode *inode = d_inode(path->dentry);
@@ -1589,7 +1591,7 @@ int ubifs_getattr(const struct path *path, struct kstat *stat,
 				STATX_ATTR_ENCRYPTED |
 				STATX_ATTR_IMMUTABLE);
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	stat->blksize = UBIFS_BLOCK_SIZE;
 	stat->size = ui->ui_size;
 
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 2bc7780d2963..0e4b4be3aa26 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1257,7 +1257,8 @@ static int do_setattr(struct ubifs_info *c, struct inode *inode,
 	return err;
 }
 
-int ubifs_setattr(struct dentry *dentry, struct iattr *attr)
+int ubifs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *attr)
 {
 	int err;
 	struct inode *inode = d_inode(dentry);
@@ -1265,7 +1266,7 @@ int ubifs_setattr(struct dentry *dentry, struct iattr *attr)
 
 	dbg_gen("ino %lu, mode %#x, ia_valid %#x",
 		inode->i_ino, inode->i_mode, attr->ia_valid);
-	err = setattr_prepare(dentry, attr);
+	err = setattr_prepare(&init_user_ns, dentry, attr);
 	if (err)
 		return err;
 
diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c
index 4363d85a3fd4..2326d5122beb 100644
--- a/fs/ubifs/ioctl.c
+++ b/fs/ubifs/ioctl.c
@@ -155,7 +155,7 @@ long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		if (IS_RDONLY(inode))
 			return -EROFS;
 
-		if (!inode_owner_or_capable(inode))
+		if (!inode_owner_or_capable(&init_user_ns, inode))
 			return -EACCES;
 
 		if (get_user(flags, (int __user *) arg))
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index fc2cdde3b549..7fdfdbda4b8a 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1989,13 +1989,14 @@ int ubifs_calc_dark(const struct ubifs_info *c, int spc);
 
 /* file.c */
 int ubifs_fsync(struct file *file, loff_t start, loff_t end, int datasync);
-int ubifs_setattr(struct dentry *dentry, struct iattr *attr);
+int ubifs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  struct iattr *attr);
 int ubifs_update_time(struct inode *inode, struct timespec64 *time, int flags);
 
 /* dir.c */
 struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir,
 			      umode_t mode);
-int ubifs_getattr(const struct path *path, struct kstat *stat,
+int ubifs_getattr(struct user_namespace *mnt_userns, const struct path *path, struct kstat *stat,
 		  u32 request_mask, unsigned int flags);
 int ubifs_check_dir_empty(struct inode *dir);
 
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index 842d5f14545d..6b1e9830b274 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -681,6 +681,7 @@ static int xattr_get(const struct xattr_handler *handler,
 }
 
 static int xattr_set(const struct xattr_handler *handler,
+			   struct user_namespace *mnt_userns,
 			   struct dentry *dentry, struct inode *inode,
 			   const char *name, const void *value,
 			   size_t size, int flags)
diff --git a/fs/udf/file.c b/fs/udf/file.c
index ad8eefad27d7..2846dcd92197 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -183,7 +183,7 @@ long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	long old_block, new_block;
 	int result;
 
-	if (inode_permission(inode, MAY_READ) != 0) {
+	if (file_permission(filp, MAY_READ) != 0) {
 		udf_debug("no permission to access inode %lu\n", inode->i_ino);
 		return -EPERM;
 	}
@@ -253,13 +253,14 @@ const struct file_operations udf_file_operations = {
 	.llseek			= generic_file_llseek,
 };
 
-static int udf_setattr(struct dentry *dentry, struct iattr *attr)
+static int udf_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		       struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct super_block *sb = inode->i_sb;
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -282,7 +283,7 @@ static int udf_setattr(struct dentry *dentry, struct iattr *attr)
 	if (attr->ia_valid & ATTR_MODE)
 		udf_update_extra_perms(inode, attr->ia_mode);
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/fs/udf/ialloc.c b/fs/udf/ialloc.c
index 84ed23edebfd..2ecf0e87660e 100644
--- a/fs/udf/ialloc.c
+++ b/fs/udf/ialloc.c
@@ -103,7 +103,7 @@ struct inode *udf_new_inode(struct inode *dir, umode_t mode)
 		mutex_unlock(&sbi->s_alloc_mutex);
 	}
 
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
 		inode->i_uid = sbi->s_uid;
 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
diff --git a/fs/udf/namei.c b/fs/udf/namei.c
index e169d8fe35b5..f146b3089f3d 100644
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -604,8 +604,8 @@ static int udf_add_nondir(struct dentry *dentry, struct inode *inode)
 	return 0;
 }
 
-static int udf_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		      bool excl)
+static int udf_create(struct user_namespace *mnt_userns, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, bool excl)
 {
 	struct inode *inode = udf_new_inode(dir, mode);
 
@@ -623,7 +623,8 @@ static int udf_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	return udf_add_nondir(dentry, inode);
 }
 
-static int udf_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int udf_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode = udf_new_inode(dir, mode);
 
@@ -642,8 +643,8 @@ static int udf_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 	return 0;
 }
 
-static int udf_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
-		     dev_t rdev)
+static int udf_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct inode *inode;
 
@@ -658,7 +659,8 @@ static int udf_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 	return udf_add_nondir(dentry, inode);
 }
 
-static int udf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int udf_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode;
 	struct udf_fileident_bh fibh;
@@ -877,8 +879,8 @@ out:
 	return retval;
 }
 
-static int udf_symlink(struct inode *dir, struct dentry *dentry,
-		       const char *symname)
+static int udf_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, const char *symname)
 {
 	struct inode *inode = udf_new_inode(dir, S_IFLNK | 0777);
 	struct pathComponent *pc;
@@ -1065,9 +1067,9 @@ static int udf_link(struct dentry *old_dentry, struct inode *dir,
 /* Anybody can rename anything with this: the permission checks are left to the
  * higher-level routines.
  */
-static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
-		      struct inode *new_dir, struct dentry *new_dentry,
-		      unsigned int flags)
+static int udf_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags)
 {
 	struct inode *old_inode = d_inode(old_dentry);
 	struct inode *new_inode = d_inode(new_dentry);
diff --git a/fs/udf/symlink.c b/fs/udf/symlink.c
index c973db239604..9b223421a3c5 100644
--- a/fs/udf/symlink.c
+++ b/fs/udf/symlink.c
@@ -152,14 +152,15 @@ out_unmap:
 	return err;
 }
 
-static int udf_symlink_getattr(const struct path *path, struct kstat *stat,
-				u32 request_mask, unsigned int flags)
+static int udf_symlink_getattr(struct user_namespace *mnt_userns,
+			       const struct path *path, struct kstat *stat,
+			       u32 request_mask, unsigned int flags)
 {
 	struct dentry *dentry = path->dentry;
 	struct inode *inode = d_backing_inode(dentry);
 	struct page *page;
 
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 	page = read_mapping_page(inode->i_mapping, 0, NULL);
 	if (IS_ERR(page))
 		return PTR_ERR(page);
diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c
index 969fd60436d3..7e3e08c0166f 100644
--- a/fs/ufs/ialloc.c
+++ b/fs/ufs/ialloc.c
@@ -289,7 +289,7 @@ cg_found:
 	ufs_mark_sb_dirty(sb);
 
 	inode->i_ino = cg * uspi->s_ipg + bit;
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 	inode->i_blocks = 0;
 	inode->i_generation = 0;
 	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
diff --git a/fs/ufs/inode.c b/fs/ufs/inode.c
index c843ec858cf7..debc282c1bb4 100644
--- a/fs/ufs/inode.c
+++ b/fs/ufs/inode.c
@@ -1211,13 +1211,14 @@ out:
 	return err;
 }
 
-int ufs_setattr(struct dentry *dentry, struct iattr *attr)
+int ufs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	unsigned int ia_valid = attr->ia_valid;
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -1227,7 +1228,7 @@ int ufs_setattr(struct dentry *dentry, struct iattr *attr)
 			return error;
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	mark_inode_dirty(inode);
 	return 0;
 }
diff --git a/fs/ufs/namei.c b/fs/ufs/namei.c
index 9ef40f100415..29d5a0e0c8f0 100644
--- a/fs/ufs/namei.c
+++ b/fs/ufs/namei.c
@@ -69,7 +69,8 @@ static struct dentry *ufs_lookup(struct inode * dir, struct dentry *dentry, unsi
  * If the create succeeds, we fill in the inode information
  * with d_instantiate(). 
  */
-static int ufs_create (struct inode * dir, struct dentry * dentry, umode_t mode,
+static int ufs_create (struct user_namespace * mnt_userns,
+		struct inode * dir, struct dentry * dentry, umode_t mode,
 		bool excl)
 {
 	struct inode *inode;
@@ -85,7 +86,8 @@ static int ufs_create (struct inode * dir, struct dentry * dentry, umode_t mode,
 	return ufs_add_nondir(dentry, inode);
 }
 
-static int ufs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
+static int ufs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode, dev_t rdev)
 {
 	struct inode *inode;
 	int err;
@@ -104,8 +106,8 @@ static int ufs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev
 	return err;
 }
 
-static int ufs_symlink (struct inode * dir, struct dentry * dentry,
-	const char * symname)
+static int ufs_symlink (struct user_namespace * mnt_userns, struct inode * dir,
+	struct dentry * dentry, const char * symname)
 {
 	struct super_block * sb = dir->i_sb;
 	int err;
@@ -164,7 +166,8 @@ static int ufs_link (struct dentry * old_dentry, struct inode * dir,
 	return error;
 }
 
-static int ufs_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
+static int ufs_mkdir(struct user_namespace * mnt_userns, struct inode * dir,
+	struct dentry * dentry, umode_t mode)
 {
 	struct inode * inode;
 	int err;
@@ -240,9 +243,9 @@ static int ufs_rmdir (struct inode * dir, struct dentry *dentry)
 	return err;
 }
 
-static int ufs_rename(struct inode *old_dir, struct dentry *old_dentry,
-		      struct inode *new_dir, struct dentry *new_dentry,
-		      unsigned int flags)
+static int ufs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
+		      struct dentry *old_dentry, struct inode *new_dir,
+		      struct dentry *new_dentry, unsigned int flags)
 {
 	struct inode *old_inode = d_inode(old_dentry);
 	struct inode *new_inode = d_inode(new_dentry);
diff --git a/fs/ufs/ufs.h b/fs/ufs/ufs.h
index b49e0efdf3d7..550f7c5a3636 100644
--- a/fs/ufs/ufs.h
+++ b/fs/ufs/ufs.h
@@ -123,7 +123,8 @@ extern struct inode *ufs_iget(struct super_block *, unsigned long);
 extern int ufs_write_inode (struct inode *, struct writeback_control *);
 extern int ufs_sync_inode (struct inode *);
 extern void ufs_evict_inode (struct inode *);
-extern int ufs_setattr(struct dentry *dentry, struct iattr *attr);
+extern int ufs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		       struct iattr *attr);
 
 /* namei.c */
 extern const struct file_operations ufs_dir_operations;
diff --git a/fs/utimes.c b/fs/utimes.c
index fd3cc4226224..39f356017635 100644
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -62,7 +62,8 @@ int vfs_utimes(const struct path *path, struct timespec64 *times)
 	}
 retry_deleg:
 	inode_lock(inode);
-	error = notify_change(path->dentry, &newattrs, &delegated_inode);
+	error = notify_change(mnt_user_ns(path->mnt), path->dentry, &newattrs,
+			      &delegated_inode);
 	inode_unlock(inode);
 	if (delegated_inode) {
 		error = break_deleg_wait(&delegated_inode);
diff --git a/fs/vboxsf/dir.c b/fs/vboxsf/dir.c
index 4d569f14a8d8..7aee0ec63ade 100644
--- a/fs/vboxsf/dir.c
+++ b/fs/vboxsf/dir.c
@@ -288,13 +288,15 @@ static int vboxsf_dir_create(struct inode *parent, struct dentry *dentry,
 	return 0;
 }
 
-static int vboxsf_dir_mkfile(struct inode *parent, struct dentry *dentry,
+static int vboxsf_dir_mkfile(struct user_namespace *mnt_userns,
+			     struct inode *parent, struct dentry *dentry,
 			     umode_t mode, bool excl)
 {
 	return vboxsf_dir_create(parent, dentry, mode, 0);
 }
 
-static int vboxsf_dir_mkdir(struct inode *parent, struct dentry *dentry,
+static int vboxsf_dir_mkdir(struct user_namespace *mnt_userns,
+			    struct inode *parent, struct dentry *dentry,
 			    umode_t mode)
 {
 	return vboxsf_dir_create(parent, dentry, mode, 1);
@@ -332,7 +334,8 @@ static int vboxsf_dir_unlink(struct inode *parent, struct dentry *dentry)
 	return 0;
 }
 
-static int vboxsf_dir_rename(struct inode *old_parent,
+static int vboxsf_dir_rename(struct user_namespace *mnt_userns,
+			     struct inode *old_parent,
 			     struct dentry *old_dentry,
 			     struct inode *new_parent,
 			     struct dentry *new_dentry,
@@ -374,7 +377,8 @@ err_put_old_path:
 	return err;
 }
 
-static int vboxsf_dir_symlink(struct inode *parent, struct dentry *dentry,
+static int vboxsf_dir_symlink(struct user_namespace *mnt_userns,
+			      struct inode *parent, struct dentry *dentry,
 			      const char *symname)
 {
 	struct vboxsf_inode *sf_parent_i = VBOXSF_I(parent);
diff --git a/fs/vboxsf/utils.c b/fs/vboxsf/utils.c
index 018057546067..3b847e3fba24 100644
--- a/fs/vboxsf/utils.c
+++ b/fs/vboxsf/utils.c
@@ -212,8 +212,8 @@ int vboxsf_inode_revalidate(struct dentry *dentry)
 	return 0;
 }
 
-int vboxsf_getattr(const struct path *path, struct kstat *kstat,
-		   u32 request_mask, unsigned int flags)
+int vboxsf_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		   struct kstat *kstat, u32 request_mask, unsigned int flags)
 {
 	int err;
 	struct dentry *dentry = path->dentry;
@@ -233,11 +233,12 @@ int vboxsf_getattr(const struct path *path, struct kstat *kstat,
 	if (err)
 		return err;
 
-	generic_fillattr(d_inode(dentry), kstat);
+	generic_fillattr(&init_user_ns, d_inode(dentry), kstat);
 	return 0;
 }
 
-int vboxsf_setattr(struct dentry *dentry, struct iattr *iattr)
+int vboxsf_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		   struct iattr *iattr)
 {
 	struct vboxsf_inode *sf_i = VBOXSF_I(d_inode(dentry));
 	struct vboxsf_sbi *sbi = VBOXSF_SBI(dentry->d_sb);
diff --git a/fs/vboxsf/vfsmod.h b/fs/vboxsf/vfsmod.h
index 18f95b00fc33..760524e78c88 100644
--- a/fs/vboxsf/vfsmod.h
+++ b/fs/vboxsf/vfsmod.h
@@ -90,9 +90,11 @@ int vboxsf_stat(struct vboxsf_sbi *sbi, struct shfl_string *path,
 		struct shfl_fsobjinfo *info);
 int vboxsf_stat_dentry(struct dentry *dentry, struct shfl_fsobjinfo *info);
 int vboxsf_inode_revalidate(struct dentry *dentry);
-int vboxsf_getattr(const struct path *path, struct kstat *kstat,
-		   u32 request_mask, unsigned int query_flags);
-int vboxsf_setattr(struct dentry *dentry, struct iattr *iattr);
+int vboxsf_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		   struct kstat *kstat, u32 request_mask,
+		   unsigned int query_flags);
+int vboxsf_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		   struct iattr *iattr);
 struct shfl_string *vboxsf_path_from_dentry(struct vboxsf_sbi *sbi,
 					    struct dentry *dentry);
 int vboxsf_nlscpy(struct vboxsf_sbi *sbi, char *name, size_t name_bound_len,
diff --git a/fs/verity/enable.c b/fs/verity/enable.c
index f7e997a01ad0..77e159a0346b 100644
--- a/fs/verity/enable.c
+++ b/fs/verity/enable.c
@@ -369,7 +369,7 @@ int fsverity_ioctl_enable(struct file *filp, const void __user *uarg)
 	 * has verity enabled, and to stabilize the data being hashed.
 	 */
 
-	err = inode_permission(inode, MAY_WRITE);
+	err = file_permission(filp, MAY_WRITE);
 	if (err)
 		return err;
 
diff --git a/fs/xattr.c b/fs/xattr.c
index fd57153b1f61..b3444e06cded 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -83,7 +83,8 @@ xattr_resolve_name(struct inode *inode, const char **name)
  * because different namespaces have very different rules.
  */
 static int
-xattr_permission(struct inode *inode, const char *name, int mask)
+xattr_permission(struct user_namespace *mnt_userns, struct inode *inode,
+		 const char *name, int mask)
 {
 	/*
 	 * We can never set or remove an extended attribute on a read-only
@@ -97,7 +98,7 @@ xattr_permission(struct inode *inode, const char *name, int mask)
 		 * to be writen back improperly if their true value is
 		 * unknown to the vfs.
 		 */
-		if (HAS_UNMAPPED_ID(inode))
+		if (HAS_UNMAPPED_ID(mnt_userns, inode))
 			return -EPERM;
 	}
 
@@ -127,11 +128,12 @@ xattr_permission(struct inode *inode, const char *name, int mask)
 		if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
 			return (mask & MAY_WRITE) ? -EPERM : -ENODATA;
 		if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) &&
-		    (mask & MAY_WRITE) && !inode_owner_or_capable(inode))
+		    (mask & MAY_WRITE) &&
+		    !inode_owner_or_capable(mnt_userns, inode))
 			return -EPERM;
 	}
 
-	return inode_permission(inode, mask);
+	return inode_permission(mnt_userns, inode, mask);
 }
 
 /*
@@ -162,8 +164,9 @@ xattr_supported_namespace(struct inode *inode, const char *prefix)
 EXPORT_SYMBOL(xattr_supported_namespace);
 
 int
-__vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
-	       const void *value, size_t size, int flags)
+__vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+	       struct inode *inode, const char *name, const void *value,
+	       size_t size, int flags)
 {
 	const struct xattr_handler *handler;
 
@@ -174,7 +177,8 @@ __vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
 		return -EOPNOTSUPP;
 	if (size == 0)
 		value = "";  /* empty EA, do not remove */
-	return handler->set(handler, dentry, inode, name, value, size, flags);
+	return handler->set(handler, mnt_userns, dentry, inode, name, value,
+			    size, flags);
 }
 EXPORT_SYMBOL(__vfs_setxattr);
 
@@ -182,6 +186,7 @@ EXPORT_SYMBOL(__vfs_setxattr);
  *  __vfs_setxattr_noperm - perform setxattr operation without performing
  *  permission checks.
  *
+ *  @mnt_userns - user namespace of the mount the inode was found from
  *  @dentry - object to perform setxattr on
  *  @name - xattr name to set
  *  @value - value to set @name to
@@ -194,8 +199,9 @@ EXPORT_SYMBOL(__vfs_setxattr);
  *  is executed. It also assumes that the caller will make the appropriate
  *  permission checks.
  */
-int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
-		const void *value, size_t size, int flags)
+int __vfs_setxattr_noperm(struct user_namespace *mnt_userns,
+			  struct dentry *dentry, const char *name,
+			  const void *value, size_t size, int flags)
 {
 	struct inode *inode = dentry->d_inode;
 	int error = -EAGAIN;
@@ -205,7 +211,8 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
 	if (issec)
 		inode->i_flags &= ~S_NOSEC;
 	if (inode->i_opflags & IOP_XATTR) {
-		error = __vfs_setxattr(dentry, inode, name, value, size, flags);
+		error = __vfs_setxattr(mnt_userns, dentry, inode, name, value,
+				       size, flags);
 		if (!error) {
 			fsnotify_xattr(dentry);
 			security_inode_post_setxattr(dentry, name, value,
@@ -244,18 +251,19 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
  *  a delegation was broken on, NULL if none.
  */
 int
-__vfs_setxattr_locked(struct dentry *dentry, const char *name,
-		const void *value, size_t size, int flags,
-		struct inode **delegated_inode)
+__vfs_setxattr_locked(struct user_namespace *mnt_userns, struct dentry *dentry,
+		      const char *name, const void *value, size_t size,
+		      int flags, struct inode **delegated_inode)
 {
 	struct inode *inode = dentry->d_inode;
 	int error;
 
-	error = xattr_permission(inode, name, MAY_WRITE);
+	error = xattr_permission(mnt_userns, inode, name, MAY_WRITE);
 	if (error)
 		return error;
 
-	error = security_inode_setxattr(dentry, name, value, size, flags);
+	error = security_inode_setxattr(mnt_userns, dentry, name, value, size,
+					flags);
 	if (error)
 		goto out;
 
@@ -263,7 +271,8 @@ __vfs_setxattr_locked(struct dentry *dentry, const char *name,
 	if (error)
 		goto out;
 
-	error = __vfs_setxattr_noperm(dentry, name, value, size, flags);
+	error = __vfs_setxattr_noperm(mnt_userns, dentry, name, value,
+				      size, flags);
 
 out:
 	return error;
@@ -271,8 +280,8 @@ out:
 EXPORT_SYMBOL_GPL(__vfs_setxattr_locked);
 
 int
-vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
-		size_t size, int flags)
+vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+	     const char *name, const void *value, size_t size, int flags)
 {
 	struct inode *inode = dentry->d_inode;
 	struct inode *delegated_inode = NULL;
@@ -280,7 +289,7 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 	int error;
 
 	if (size && strcmp(name, XATTR_NAME_CAPS) == 0) {
-		error = cap_convert_nscap(dentry, &value, size);
+		error = cap_convert_nscap(mnt_userns, dentry, &value, size);
 		if (error < 0)
 			return error;
 		size = error;
@@ -288,8 +297,8 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 
 retry_deleg:
 	inode_lock(inode);
-	error = __vfs_setxattr_locked(dentry, name, value, size, flags,
-	    &delegated_inode);
+	error = __vfs_setxattr_locked(mnt_userns, dentry, name, value, size,
+				      flags, &delegated_inode);
 	inode_unlock(inode);
 
 	if (delegated_inode) {
@@ -305,18 +314,20 @@ retry_deleg:
 EXPORT_SYMBOL_GPL(vfs_setxattr);
 
 static ssize_t
-xattr_getsecurity(struct inode *inode, const char *name, void *value,
-			size_t size)
+xattr_getsecurity(struct user_namespace *mnt_userns, struct inode *inode,
+		  const char *name, void *value, size_t size)
 {
 	void *buffer = NULL;
 	ssize_t len;
 
 	if (!value || !size) {
-		len = security_inode_getsecurity(inode, name, &buffer, false);
+		len = security_inode_getsecurity(mnt_userns, inode, name,
+						 &buffer, false);
 		goto out_noalloc;
 	}
 
-	len = security_inode_getsecurity(inode, name, &buffer, true);
+	len = security_inode_getsecurity(mnt_userns, inode, name, &buffer,
+					 true);
 	if (len < 0)
 		return len;
 	if (size < len) {
@@ -339,15 +350,16 @@ out_noalloc:
  * Returns the result of alloc, if failed, or the getxattr operation.
  */
 ssize_t
-vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value,
-		   size_t xattr_size, gfp_t flags)
+vfs_getxattr_alloc(struct user_namespace *mnt_userns, struct dentry *dentry,
+		   const char *name, char **xattr_value, size_t xattr_size,
+		   gfp_t flags)
 {
 	const struct xattr_handler *handler;
 	struct inode *inode = dentry->d_inode;
 	char *value = *xattr_value;
 	int error;
 
-	error = xattr_permission(inode, name, MAY_READ);
+	error = xattr_permission(mnt_userns, inode, name, MAY_READ);
 	if (error)
 		return error;
 
@@ -388,12 +400,13 @@ __vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name,
 EXPORT_SYMBOL(__vfs_getxattr);
 
 ssize_t
-vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size)
+vfs_getxattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+	     const char *name, void *value, size_t size)
 {
 	struct inode *inode = dentry->d_inode;
 	int error;
 
-	error = xattr_permission(inode, name, MAY_READ);
+	error = xattr_permission(mnt_userns, inode, name, MAY_READ);
 	if (error)
 		return error;
 
@@ -404,7 +417,8 @@ vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size)
 	if (!strncmp(name, XATTR_SECURITY_PREFIX,
 				XATTR_SECURITY_PREFIX_LEN)) {
 		const char *suffix = name + XATTR_SECURITY_PREFIX_LEN;
-		int ret = xattr_getsecurity(inode, suffix, value, size);
+		int ret = xattr_getsecurity(mnt_userns, inode, suffix, value,
+					    size);
 		/*
 		 * Only overwrite the return value if a security module
 		 * is actually active.
@@ -439,7 +453,8 @@ vfs_listxattr(struct dentry *dentry, char *list, size_t size)
 EXPORT_SYMBOL_GPL(vfs_listxattr);
 
 int
-__vfs_removexattr(struct dentry *dentry, const char *name)
+__vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		  const char *name)
 {
 	struct inode *inode = d_inode(dentry);
 	const struct xattr_handler *handler;
@@ -449,7 +464,8 @@ __vfs_removexattr(struct dentry *dentry, const char *name)
 		return PTR_ERR(handler);
 	if (!handler->set)
 		return -EOPNOTSUPP;
-	return handler->set(handler, dentry, inode, name, NULL, 0, XATTR_REPLACE);
+	return handler->set(handler, mnt_userns, dentry, inode, name, NULL, 0,
+			    XATTR_REPLACE);
 }
 EXPORT_SYMBOL(__vfs_removexattr);
 
@@ -463,17 +479,18 @@ EXPORT_SYMBOL(__vfs_removexattr);
  *  a delegation was broken on, NULL if none.
  */
 int
-__vfs_removexattr_locked(struct dentry *dentry, const char *name,
-		struct inode **delegated_inode)
+__vfs_removexattr_locked(struct user_namespace *mnt_userns,
+			 struct dentry *dentry, const char *name,
+			 struct inode **delegated_inode)
 {
 	struct inode *inode = dentry->d_inode;
 	int error;
 
-	error = xattr_permission(inode, name, MAY_WRITE);
+	error = xattr_permission(mnt_userns, inode, name, MAY_WRITE);
 	if (error)
 		return error;
 
-	error = security_inode_removexattr(dentry, name);
+	error = security_inode_removexattr(mnt_userns, dentry, name);
 	if (error)
 		goto out;
 
@@ -481,7 +498,7 @@ __vfs_removexattr_locked(struct dentry *dentry, const char *name,
 	if (error)
 		goto out;
 
-	error = __vfs_removexattr(dentry, name);
+	error = __vfs_removexattr(mnt_userns, dentry, name);
 
 	if (!error) {
 		fsnotify_xattr(dentry);
@@ -494,7 +511,8 @@ out:
 EXPORT_SYMBOL_GPL(__vfs_removexattr_locked);
 
 int
-vfs_removexattr(struct dentry *dentry, const char *name)
+vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		const char *name)
 {
 	struct inode *inode = dentry->d_inode;
 	struct inode *delegated_inode = NULL;
@@ -502,7 +520,8 @@ vfs_removexattr(struct dentry *dentry, const char *name)
 
 retry_deleg:
 	inode_lock(inode);
-	error = __vfs_removexattr_locked(dentry, name, &delegated_inode);
+	error = __vfs_removexattr_locked(mnt_userns, dentry,
+					 name, &delegated_inode);
 	inode_unlock(inode);
 
 	if (delegated_inode) {
@@ -519,8 +538,9 @@ EXPORT_SYMBOL_GPL(vfs_removexattr);
  * Extended attribute SET operations
  */
 static long
-setxattr(struct dentry *d, const char __user *name, const void __user *value,
-	 size_t size, int flags)
+setxattr(struct user_namespace *mnt_userns, struct dentry *d,
+	 const char __user *name, const void __user *value, size_t size,
+	 int flags)
 {
 	int error;
 	void *kvalue = NULL;
@@ -547,10 +567,10 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
 		}
 		if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
 		    (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
-			posix_acl_fix_xattr_from_user(kvalue, size);
+			posix_acl_fix_xattr_from_user(mnt_userns, kvalue, size);
 	}
 
-	error = vfs_setxattr(d, kname, kvalue, size, flags);
+	error = vfs_setxattr(mnt_userns, d, kname, kvalue, size, flags);
 out:
 	kvfree(kvalue);
 
@@ -563,13 +583,15 @@ static int path_setxattr(const char __user *pathname,
 {
 	struct path path;
 	int error;
+
 retry:
 	error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
 	if (error)
 		return error;
 	error = mnt_want_write(path.mnt);
 	if (!error) {
-		error = setxattr(path.dentry, name, value, size, flags);
+		error = setxattr(mnt_user_ns(path.mnt), path.dentry, name,
+				 value, size, flags);
 		mnt_drop_write(path.mnt);
 	}
 	path_put(&path);
@@ -605,7 +627,9 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name,
 	audit_file(f.file);
 	error = mnt_want_write_file(f.file);
 	if (!error) {
-		error = setxattr(f.file->f_path.dentry, name, value, size, flags);
+		error = setxattr(file_mnt_user_ns(f.file),
+				 f.file->f_path.dentry, name,
+				 value, size, flags);
 		mnt_drop_write_file(f.file);
 	}
 	fdput(f);
@@ -616,8 +640,8 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name,
  * Extended attribute GET operations
  */
 static ssize_t
-getxattr(struct dentry *d, const char __user *name, void __user *value,
-	 size_t size)
+getxattr(struct user_namespace *mnt_userns, struct dentry *d,
+	 const char __user *name, void __user *value, size_t size)
 {
 	ssize_t error;
 	void *kvalue = NULL;
@@ -637,11 +661,11 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 			return -ENOMEM;
 	}
 
-	error = vfs_getxattr(d, kname, kvalue, size);
+	error = vfs_getxattr(mnt_userns, d, kname, kvalue, size);
 	if (error > 0) {
 		if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
 		    (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
-			posix_acl_fix_xattr_to_user(kvalue, error);
+			posix_acl_fix_xattr_to_user(mnt_userns, kvalue, error);
 		if (size && copy_to_user(value, kvalue, error))
 			error = -EFAULT;
 	} else if (error == -ERANGE && size >= XATTR_SIZE_MAX) {
@@ -665,7 +689,7 @@ retry:
 	error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
 	if (error)
 		return error;
-	error = getxattr(path.dentry, name, value, size);
+	error = getxattr(mnt_user_ns(path.mnt), path.dentry, name, value, size);
 	path_put(&path);
 	if (retry_estale(error, lookup_flags)) {
 		lookup_flags |= LOOKUP_REVAL;
@@ -695,7 +719,8 @@ SYSCALL_DEFINE4(fgetxattr, int, fd, const char __user *, name,
 	if (!f.file)
 		return error;
 	audit_file(f.file);
-	error = getxattr(f.file->f_path.dentry, name, value, size);
+	error = getxattr(file_mnt_user_ns(f.file), f.file->f_path.dentry,
+			 name, value, size);
 	fdput(f);
 	return error;
 }
@@ -779,7 +804,8 @@ SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size)
  * Extended attribute REMOVE operations
  */
 static long
-removexattr(struct dentry *d, const char __user *name)
+removexattr(struct user_namespace *mnt_userns, struct dentry *d,
+	    const char __user *name)
 {
 	int error;
 	char kname[XATTR_NAME_MAX + 1];
@@ -790,7 +816,7 @@ removexattr(struct dentry *d, const char __user *name)
 	if (error < 0)
 		return error;
 
-	return vfs_removexattr(d, kname);
+	return vfs_removexattr(mnt_userns, d, kname);
 }
 
 static int path_removexattr(const char __user *pathname,
@@ -804,7 +830,7 @@ retry:
 		return error;
 	error = mnt_want_write(path.mnt);
 	if (!error) {
-		error = removexattr(path.dentry, name);
+		error = removexattr(mnt_user_ns(path.mnt), path.dentry, name);
 		mnt_drop_write(path.mnt);
 	}
 	path_put(&path);
@@ -837,7 +863,8 @@ SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name)
 	audit_file(f.file);
 	error = mnt_want_write_file(f.file);
 	if (!error) {
-		error = removexattr(f.file->f_path.dentry, name);
+		error = removexattr(file_mnt_user_ns(f.file),
+				    f.file->f_path.dentry, name);
 		mnt_drop_write_file(f.file);
 	}
 	fdput(f);
diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
index 779cb73b3d00..d02bef24b32b 100644
--- a/fs/xfs/xfs_acl.c
+++ b/fs/xfs/xfs_acl.c
@@ -238,7 +238,8 @@ xfs_acl_set_mode(
 }
 
 int
-xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+xfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+	    struct posix_acl *acl, int type)
 {
 	umode_t mode;
 	bool set_mode = false;
@@ -252,7 +253,7 @@ xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 		return error;
 
 	if (type == ACL_TYPE_ACCESS) {
-		error = posix_acl_update_mode(inode, &mode, &acl);
+		error = posix_acl_update_mode(mnt_userns, inode, &mode, &acl);
 		if (error)
 			return error;
 		set_mode = true;
diff --git a/fs/xfs/xfs_acl.h b/fs/xfs/xfs_acl.h
index c042c0868016..7bdb3a4ed798 100644
--- a/fs/xfs/xfs_acl.h
+++ b/fs/xfs/xfs_acl.h
@@ -11,7 +11,8 @@ struct posix_acl;
 
 #ifdef CONFIG_XFS_POSIX_ACL
 extern struct posix_acl *xfs_get_acl(struct inode *inode, int type);
-extern int xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
+extern int xfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		       struct posix_acl *acl, int type);
 extern int __xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
 void xfs_forget_acl(struct inode *inode, const char *name);
 #else
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 68ca1b40d8c7..a007ca0711d9 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -29,6 +29,7 @@
 #include <linux/backing-dev.h>
 #include <linux/mman.h>
 #include <linux/fadvise.h>
+#include <linux/mount.h>
 
 static const struct vm_operations_struct xfs_file_vm_ops;
 
@@ -1051,7 +1052,8 @@ xfs_file_fallocate(
 
 		iattr.ia_valid = ATTR_SIZE;
 		iattr.ia_size = new_size;
-		error = xfs_vn_setattr_size(file_dentry(file), &iattr);
+		error = xfs_vn_setattr_size(file_mnt_user_ns(file),
+					    file_dentry(file), &iattr);
 		if (error)
 			goto out_unlock;
 	}
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 636ac13b1df2..46a861d55e48 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -766,6 +766,7 @@ xfs_inode_inherit_flags2(
  */
 static int
 xfs_init_new_inode(
+	struct user_namespace	*mnt_userns,
 	struct xfs_trans	*tp,
 	struct xfs_inode	*pip,
 	xfs_ino_t		ino,
@@ -811,11 +812,11 @@ xfs_init_new_inode(
 
 	if (dir && !(dir->i_mode & S_ISGID) &&
 	    (mp->m_flags & XFS_MOUNT_GRPID)) {
-		inode->i_uid = current_fsuid();
+		inode->i_uid = fsuid_into_mnt(mnt_userns);
 		inode->i_gid = dir->i_gid;
 		inode->i_mode = mode;
 	} else {
-		inode_init_owner(inode, dir, mode);
+		inode_init_owner(mnt_userns, inode, dir, mode);
 	}
 
 	/*
@@ -824,7 +825,8 @@ xfs_init_new_inode(
 	 * (and only if the irix_sgid_inherit compatibility variable is set).
 	 */
 	if (irix_sgid_inherit &&
-	    (inode->i_mode & S_ISGID) && !in_group_p(inode->i_gid))
+	    (inode->i_mode & S_ISGID) &&
+	    !in_group_p(i_gid_into_mnt(mnt_userns, inode)))
 		inode->i_mode &= ~S_ISGID;
 
 	ip->i_d.di_size = 0;
@@ -901,6 +903,7 @@ xfs_init_new_inode(
  */
 int
 xfs_dir_ialloc(
+	struct user_namespace	*mnt_userns,
 	struct xfs_trans	**tpp,
 	struct xfs_inode	*dp,
 	umode_t			mode,
@@ -933,7 +936,8 @@ xfs_dir_ialloc(
 		return error;
 	ASSERT(ino != NULLFSINO);
 
-	return xfs_init_new_inode(*tpp, dp, ino, mode, nlink, rdev, prid, ipp);
+	return xfs_init_new_inode(mnt_userns, *tpp, dp, ino, mode, nlink, rdev,
+				  prid, ipp);
 }
 
 /*
@@ -973,6 +977,7 @@ xfs_bumplink(
 
 int
 xfs_create(
+	struct user_namespace	*mnt_userns,
 	xfs_inode_t		*dp,
 	struct xfs_name		*name,
 	umode_t			mode,
@@ -1046,7 +1051,8 @@ xfs_create(
 	 * entry pointing to them, but a directory also the "." entry
 	 * pointing to itself.
 	 */
-	error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, &ip);
+	error = xfs_dir_ialloc(mnt_userns, &tp, dp, mode, is_dir ? 2 : 1, rdev,
+			       prid, &ip);
 	if (error)
 		goto out_trans_cancel;
 
@@ -1127,6 +1133,7 @@ xfs_create(
 
 int
 xfs_create_tmpfile(
+	struct user_namespace	*mnt_userns,
 	struct xfs_inode	*dp,
 	umode_t			mode,
 	struct xfs_inode	**ipp)
@@ -1164,7 +1171,7 @@ xfs_create_tmpfile(
 	if (error)
 		goto out_release_dquots;
 
-	error = xfs_dir_ialloc(&tp, dp, mode, 0, 0, prid, &ip);
+	error = xfs_dir_ialloc(mnt_userns, &tp, dp, mode, 0, 0, prid, &ip);
 	if (error)
 		goto out_trans_cancel;
 
@@ -2977,13 +2984,15 @@ out_trans_abort:
  */
 static int
 xfs_rename_alloc_whiteout(
+	struct user_namespace	*mnt_userns,
 	struct xfs_inode	*dp,
 	struct xfs_inode	**wip)
 {
 	struct xfs_inode	*tmpfile;
 	int			error;
 
-	error = xfs_create_tmpfile(dp, S_IFCHR | WHITEOUT_MODE, &tmpfile);
+	error = xfs_create_tmpfile(mnt_userns, dp, S_IFCHR | WHITEOUT_MODE,
+				   &tmpfile);
 	if (error)
 		return error;
 
@@ -3005,6 +3014,7 @@ xfs_rename_alloc_whiteout(
  */
 int
 xfs_rename(
+	struct user_namespace	*mnt_userns,
 	struct xfs_inode	*src_dp,
 	struct xfs_name		*src_name,
 	struct xfs_inode	*src_ip,
@@ -3036,7 +3046,7 @@ xfs_rename(
 	 */
 	if (flags & RENAME_WHITEOUT) {
 		ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
-		error = xfs_rename_alloc_whiteout(target_dp, &wip);
+		error = xfs_rename_alloc_whiteout(mnt_userns, target_dp, &wip);
 		if (error)
 			return error;
 
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index eca333f5f715..88ee4c3930ae 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -369,15 +369,18 @@ int		xfs_release(struct xfs_inode *ip);
 void		xfs_inactive(struct xfs_inode *ip);
 int		xfs_lookup(struct xfs_inode *dp, struct xfs_name *name,
 			   struct xfs_inode **ipp, struct xfs_name *ci_name);
-int		xfs_create(struct xfs_inode *dp, struct xfs_name *name,
+int		xfs_create(struct user_namespace *mnt_userns,
+			   struct xfs_inode *dp, struct xfs_name *name,
 			   umode_t mode, dev_t rdev, struct xfs_inode **ipp);
-int		xfs_create_tmpfile(struct xfs_inode *dp, umode_t mode,
+int		xfs_create_tmpfile(struct user_namespace *mnt_userns,
+			   struct xfs_inode *dp, umode_t mode,
 			   struct xfs_inode **ipp);
 int		xfs_remove(struct xfs_inode *dp, struct xfs_name *name,
 			   struct xfs_inode *ip);
 int		xfs_link(struct xfs_inode *tdp, struct xfs_inode *sip,
 			 struct xfs_name *target_name);
-int		xfs_rename(struct xfs_inode *src_dp, struct xfs_name *src_name,
+int		xfs_rename(struct user_namespace *mnt_userns,
+			   struct xfs_inode *src_dp, struct xfs_name *src_name,
 			   struct xfs_inode *src_ip, struct xfs_inode *target_dp,
 			   struct xfs_name *target_name,
 			   struct xfs_inode *target_ip, unsigned int flags);
@@ -407,9 +410,10 @@ void		xfs_lock_two_inodes(struct xfs_inode *ip0, uint ip0_mode,
 xfs_extlen_t	xfs_get_extsz_hint(struct xfs_inode *ip);
 xfs_extlen_t	xfs_get_cowextsz_hint(struct xfs_inode *ip);
 
-int xfs_dir_ialloc(struct xfs_trans **tpp, struct xfs_inode *dp, umode_t mode,
-		   xfs_nlink_t nlink, dev_t dev, prid_t prid,
-		   struct xfs_inode **ipp);
+int		xfs_dir_ialloc(struct user_namespace *mnt_userns,
+			       struct xfs_trans **tpp, struct xfs_inode *dp,
+			       umode_t mode, xfs_nlink_t nlink, dev_t dev,
+			       prid_t prid, struct xfs_inode **ipp);
 
 static inline int
 xfs_itruncate_extents(
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 248083ea0276..99dfe89a8d08 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -693,7 +693,8 @@ xfs_ioc_space(
 
 	iattr.ia_valid = ATTR_SIZE;
 	iattr.ia_size = bf->l_start;
-	error = xfs_vn_setattr_size(file_dentry(filp), &iattr);
+	error = xfs_vn_setattr_size(file_mnt_user_ns(filp), file_dentry(filp),
+				    &iattr);
 	if (error)
 		goto out_unlock;
 
@@ -734,13 +735,15 @@ xfs_fsinumbers_fmt(
 
 STATIC int
 xfs_ioc_fsbulkstat(
-	xfs_mount_t		*mp,
+	struct file		*file,
 	unsigned int		cmd,
 	void			__user *arg)
 {
+	struct xfs_mount	*mp = XFS_I(file_inode(file))->i_mount;
 	struct xfs_fsop_bulkreq	bulkreq;
 	struct xfs_ibulk	breq = {
 		.mp		= mp,
+		.mnt_userns	= file_mnt_user_ns(file),
 		.ocount		= 0,
 	};
 	xfs_ino_t		lastino;
@@ -908,13 +911,15 @@ xfs_bulk_ireq_teardown(
 /* Handle the v5 bulkstat ioctl. */
 STATIC int
 xfs_ioc_bulkstat(
-	struct xfs_mount		*mp,
+	struct file			*file,
 	unsigned int			cmd,
 	struct xfs_bulkstat_req __user	*arg)
 {
+	struct xfs_mount		*mp = XFS_I(file_inode(file))->i_mount;
 	struct xfs_bulk_ireq		hdr;
 	struct xfs_ibulk		breq = {
 		.mp			= mp,
+		.mnt_userns		= file_mnt_user_ns(file),
 	};
 	int				error;
 
@@ -1275,9 +1280,10 @@ xfs_ioctl_setattr_prepare_dax(
  */
 static struct xfs_trans *
 xfs_ioctl_setattr_get_trans(
-	struct xfs_inode	*ip,
+	struct file		*file,
 	struct xfs_dquot	*pdqp)
 {
+	struct xfs_inode	*ip = XFS_I(file_inode(file));
 	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_trans	*tp;
 	int			error = -EROFS;
@@ -1299,7 +1305,7 @@ xfs_ioctl_setattr_get_trans(
 	 * The user ID of the calling process must be equal to the file owner
 	 * ID, except in cases where the CAP_FSETID capability is applicable.
 	 */
-	if (!inode_owner_or_capable(VFS_I(ip))) {
+	if (!inode_owner_or_capable(file_mnt_user_ns(file), VFS_I(ip))) {
 		error = -EPERM;
 		goto out_cancel;
 	}
@@ -1427,9 +1433,11 @@ xfs_ioctl_setattr_check_projid(
 
 STATIC int
 xfs_ioctl_setattr(
-	xfs_inode_t		*ip,
+	struct file		*file,
 	struct fsxattr		*fa)
 {
+	struct user_namespace	*mnt_userns = file_mnt_user_ns(file);
+	struct xfs_inode	*ip = XFS_I(file_inode(file));
 	struct fsxattr		old_fa;
 	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_trans	*tp;
@@ -1461,7 +1469,7 @@ xfs_ioctl_setattr(
 
 	xfs_ioctl_setattr_prepare_dax(ip, fa);
 
-	tp = xfs_ioctl_setattr_get_trans(ip, pdqp);
+	tp = xfs_ioctl_setattr_get_trans(file, pdqp);
 	if (IS_ERR(tp)) {
 		error = PTR_ERR(tp);
 		goto error_free_dquots;
@@ -1493,7 +1501,7 @@ xfs_ioctl_setattr(
 	 */
 
 	if ((VFS_I(ip)->i_mode & (S_ISUID|S_ISGID)) &&
-	    !capable_wrt_inode_uidgid(VFS_I(ip), CAP_FSETID))
+	    !capable_wrt_inode_uidgid(mnt_userns, VFS_I(ip), CAP_FSETID))
 		VFS_I(ip)->i_mode &= ~(S_ISUID|S_ISGID);
 
 	/* Change the ownerships and register project quota modifications */
@@ -1540,7 +1548,6 @@ error_free_dquots:
 
 STATIC int
 xfs_ioc_fssetxattr(
-	xfs_inode_t		*ip,
 	struct file		*filp,
 	void			__user *arg)
 {
@@ -1553,7 +1560,7 @@ xfs_ioc_fssetxattr(
 	error = mnt_want_write_file(filp);
 	if (error)
 		return error;
-	error = xfs_ioctl_setattr(ip, &fa);
+	error = xfs_ioctl_setattr(filp, &fa);
 	mnt_drop_write_file(filp);
 	return error;
 }
@@ -1599,7 +1606,7 @@ xfs_ioc_setxflags(
 
 	xfs_ioctl_setattr_prepare_dax(ip, &fa);
 
-	tp = xfs_ioctl_setattr_get_trans(ip, NULL);
+	tp = xfs_ioctl_setattr_get_trans(filp, NULL);
 	if (IS_ERR(tp)) {
 		error = PTR_ERR(tp);
 		goto out_drop_write;
@@ -2110,10 +2117,10 @@ xfs_file_ioctl(
 	case XFS_IOC_FSBULKSTAT_SINGLE:
 	case XFS_IOC_FSBULKSTAT:
 	case XFS_IOC_FSINUMBERS:
-		return xfs_ioc_fsbulkstat(mp, cmd, arg);
+		return xfs_ioc_fsbulkstat(filp, cmd, arg);
 
 	case XFS_IOC_BULKSTAT:
-		return xfs_ioc_bulkstat(mp, cmd, arg);
+		return xfs_ioc_bulkstat(filp, cmd, arg);
 	case XFS_IOC_INUMBERS:
 		return xfs_ioc_inumbers(mp, cmd, arg);
 
@@ -2135,7 +2142,7 @@ xfs_file_ioctl(
 	case XFS_IOC_FSGETXATTRA:
 		return xfs_ioc_fsgetxattr(ip, 1, arg);
 	case XFS_IOC_FSSETXATTR:
-		return xfs_ioc_fssetxattr(ip, filp, arg);
+		return xfs_ioc_fssetxattr(filp, arg);
 	case XFS_IOC_GETXFLAGS:
 		return xfs_ioc_getxflags(ip, arg);
 	case XFS_IOC_SETXFLAGS:
diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
index c1771e728117..33c09ec8e6c0 100644
--- a/fs/xfs/xfs_ioctl32.c
+++ b/fs/xfs/xfs_ioctl32.c
@@ -209,14 +209,16 @@ xfs_fsbulkstat_one_fmt_compat(
 /* copied from xfs_ioctl.c */
 STATIC int
 xfs_compat_ioc_fsbulkstat(
-	xfs_mount_t		  *mp,
+	struct file		*file,
 	unsigned int		  cmd,
 	struct compat_xfs_fsop_bulkreq __user *p32)
 {
+	struct xfs_mount	*mp = XFS_I(file_inode(file))->i_mount;
 	u32			addr;
 	struct xfs_fsop_bulkreq	bulkreq;
 	struct xfs_ibulk	breq = {
 		.mp		= mp,
+		.mnt_userns	= file_mnt_user_ns(file),
 		.ocount		= 0,
 	};
 	xfs_ino_t		lastino;
@@ -436,7 +438,6 @@ xfs_file_compat_ioctl(
 {
 	struct inode		*inode = file_inode(filp);
 	struct xfs_inode	*ip = XFS_I(inode);
-	struct xfs_mount	*mp = ip->i_mount;
 	void			__user *arg = compat_ptr(p);
 	int			error;
 
@@ -456,7 +457,7 @@ xfs_file_compat_ioctl(
 		return xfs_ioc_space(filp, &bf);
 	}
 	case XFS_IOC_FSGEOMETRY_V1_32:
-		return xfs_compat_ioc_fsgeometry_v1(mp, arg);
+		return xfs_compat_ioc_fsgeometry_v1(ip->i_mount, arg);
 	case XFS_IOC_FSGROWFSDATA_32: {
 		struct xfs_growfs_data	in;
 
@@ -465,7 +466,7 @@ xfs_file_compat_ioctl(
 		error = mnt_want_write_file(filp);
 		if (error)
 			return error;
-		error = xfs_growfs_data(mp, &in);
+		error = xfs_growfs_data(ip->i_mount, &in);
 		mnt_drop_write_file(filp);
 		return error;
 	}
@@ -477,7 +478,7 @@ xfs_file_compat_ioctl(
 		error = mnt_want_write_file(filp);
 		if (error)
 			return error;
-		error = xfs_growfs_rt(mp, &in);
+		error = xfs_growfs_rt(ip->i_mount, &in);
 		mnt_drop_write_file(filp);
 		return error;
 	}
@@ -507,7 +508,7 @@ xfs_file_compat_ioctl(
 	case XFS_IOC_FSBULKSTAT_32:
 	case XFS_IOC_FSBULKSTAT_SINGLE_32:
 	case XFS_IOC_FSINUMBERS_32:
-		return xfs_compat_ioc_fsbulkstat(mp, cmd, arg);
+		return xfs_compat_ioc_fsbulkstat(filp, cmd, arg);
 	case XFS_IOC_FD_TO_HANDLE_32:
 	case XFS_IOC_PATH_TO_HANDLE_32:
 	case XFS_IOC_PATH_TO_FSHANDLE_32: {
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 00369502fe25..66ebccb5a6ff 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -128,6 +128,7 @@ xfs_cleanup_inode(
 
 STATIC int
 xfs_generic_create(
+	struct user_namespace	*mnt_userns,
 	struct inode	*dir,
 	struct dentry	*dentry,
 	umode_t		mode,
@@ -161,9 +162,10 @@ xfs_generic_create(
 		goto out_free_acl;
 
 	if (!tmpfile) {
-		error = xfs_create(XFS_I(dir), &name, mode, rdev, &ip);
+		error = xfs_create(mnt_userns, XFS_I(dir), &name, mode, rdev,
+				   &ip);
 	} else {
-		error = xfs_create_tmpfile(XFS_I(dir), mode, &ip);
+		error = xfs_create_tmpfile(mnt_userns, XFS_I(dir), mode, &ip);
 	}
 	if (unlikely(error))
 		goto out_free_acl;
@@ -220,31 +222,35 @@ xfs_generic_create(
 
 STATIC int
 xfs_vn_mknod(
-	struct inode	*dir,
-	struct dentry	*dentry,
-	umode_t		mode,
-	dev_t		rdev)
+	struct user_namespace	*mnt_userns,
+	struct inode		*dir,
+	struct dentry		*dentry,
+	umode_t			mode,
+	dev_t			rdev)
 {
-	return xfs_generic_create(dir, dentry, mode, rdev, false);
+	return xfs_generic_create(mnt_userns, dir, dentry, mode, rdev, false);
 }
 
 STATIC int
 xfs_vn_create(
-	struct inode	*dir,
-	struct dentry	*dentry,
-	umode_t		mode,
-	bool		flags)
+	struct user_namespace	*mnt_userns,
+	struct inode		*dir,
+	struct dentry		*dentry,
+	umode_t			mode,
+	bool			flags)
 {
-	return xfs_generic_create(dir, dentry, mode, 0, false);
+	return xfs_generic_create(mnt_userns, dir, dentry, mode, 0, false);
 }
 
 STATIC int
 xfs_vn_mkdir(
-	struct inode	*dir,
-	struct dentry	*dentry,
-	umode_t		mode)
+	struct user_namespace	*mnt_userns,
+	struct inode		*dir,
+	struct dentry		*dentry,
+	umode_t			mode)
 {
-	return xfs_generic_create(dir, dentry, mode | S_IFDIR, 0, false);
+	return xfs_generic_create(mnt_userns, dir, dentry, mode | S_IFDIR, 0,
+				  false);
 }
 
 STATIC struct dentry *
@@ -361,9 +367,10 @@ xfs_vn_unlink(
 
 STATIC int
 xfs_vn_symlink(
-	struct inode	*dir,
-	struct dentry	*dentry,
-	const char	*symname)
+	struct user_namespace	*mnt_userns,
+	struct inode		*dir,
+	struct dentry		*dentry,
+	const char		*symname)
 {
 	struct inode	*inode;
 	struct xfs_inode *cip = NULL;
@@ -377,7 +384,7 @@ xfs_vn_symlink(
 	if (unlikely(error))
 		goto out;
 
-	error = xfs_symlink(XFS_I(dir), &name, symname, mode, &cip);
+	error = xfs_symlink(mnt_userns, XFS_I(dir), &name, symname, mode, &cip);
 	if (unlikely(error))
 		goto out;
 
@@ -403,11 +410,12 @@ xfs_vn_symlink(
 
 STATIC int
 xfs_vn_rename(
-	struct inode	*odir,
-	struct dentry	*odentry,
-	struct inode	*ndir,
-	struct dentry	*ndentry,
-	unsigned int	flags)
+	struct user_namespace	*mnt_userns,
+	struct inode		*odir,
+	struct dentry		*odentry,
+	struct inode		*ndir,
+	struct dentry		*ndentry,
+	unsigned int		flags)
 {
 	struct inode	*new_inode = d_inode(ndentry);
 	int		omode = 0;
@@ -431,8 +439,8 @@ xfs_vn_rename(
 	if (unlikely(error))
 		return error;
 
-	return xfs_rename(XFS_I(odir), &oname, XFS_I(d_inode(odentry)),
-			  XFS_I(ndir), &nname,
+	return xfs_rename(mnt_userns, XFS_I(odir), &oname,
+			  XFS_I(d_inode(odentry)), XFS_I(ndir), &nname,
 			  new_inode ? XFS_I(new_inode) : NULL, flags);
 }
 
@@ -529,6 +537,7 @@ xfs_stat_blksize(
 
 STATIC int
 xfs_vn_getattr(
+	struct user_namespace	*mnt_userns,
 	const struct path	*path,
 	struct kstat		*stat,
 	u32			request_mask,
@@ -547,8 +556,8 @@ xfs_vn_getattr(
 	stat->dev = inode->i_sb->s_dev;
 	stat->mode = inode->i_mode;
 	stat->nlink = inode->i_nlink;
-	stat->uid = inode->i_uid;
-	stat->gid = inode->i_gid;
+	stat->uid = i_uid_into_mnt(mnt_userns, inode);
+	stat->gid = i_gid_into_mnt(mnt_userns, inode);
 	stat->ino = ip->i_ino;
 	stat->atime = inode->i_atime;
 	stat->mtime = inode->i_mtime;
@@ -626,8 +635,9 @@ xfs_setattr_time(
 
 static int
 xfs_vn_change_ok(
-	struct dentry	*dentry,
-	struct iattr	*iattr)
+	struct user_namespace	*mnt_userns,
+	struct dentry		*dentry,
+	struct iattr		*iattr)
 {
 	struct xfs_mount	*mp = XFS_I(d_inode(dentry))->i_mount;
 
@@ -637,7 +647,7 @@ xfs_vn_change_ok(
 	if (XFS_FORCED_SHUTDOWN(mp))
 		return -EIO;
 
-	return setattr_prepare(dentry, iattr);
+	return setattr_prepare(mnt_userns, dentry, iattr);
 }
 
 /*
@@ -648,6 +658,7 @@ xfs_vn_change_ok(
  */
 static int
 xfs_setattr_nonsize(
+	struct user_namespace	*mnt_userns,
 	struct xfs_inode	*ip,
 	struct iattr		*iattr)
 {
@@ -788,7 +799,7 @@ xfs_setattr_nonsize(
 	 * 	     Posix ACL code seems to care about this issue either.
 	 */
 	if (mask & ATTR_MODE) {
-		error = posix_acl_chmod(inode, inode->i_mode);
+		error = posix_acl_chmod(mnt_userns, inode, inode->i_mode);
 		if (error)
 			return error;
 	}
@@ -809,6 +820,7 @@ out_dqrele:
  */
 STATIC int
 xfs_setattr_size(
+	struct user_namespace	*mnt_userns,
 	struct xfs_inode	*ip,
 	struct iattr		*iattr)
 {
@@ -840,7 +852,7 @@ xfs_setattr_size(
 		 * Use the regular setattr path to update the timestamps.
 		 */
 		iattr->ia_valid &= ~ATTR_SIZE;
-		return xfs_setattr_nonsize(ip, iattr);
+		return xfs_setattr_nonsize(mnt_userns, ip, iattr);
 	}
 
 	/*
@@ -1009,6 +1021,7 @@ out_trans_cancel:
 
 int
 xfs_vn_setattr_size(
+	struct user_namespace	*mnt_userns,
 	struct dentry		*dentry,
 	struct iattr		*iattr)
 {
@@ -1017,14 +1030,15 @@ xfs_vn_setattr_size(
 
 	trace_xfs_setattr(ip);
 
-	error = xfs_vn_change_ok(dentry, iattr);
+	error = xfs_vn_change_ok(mnt_userns, dentry, iattr);
 	if (error)
 		return error;
-	return xfs_setattr_size(ip, iattr);
+	return xfs_setattr_size(mnt_userns, ip, iattr);
 }
 
 STATIC int
 xfs_vn_setattr(
+	struct user_namespace	*mnt_userns,
 	struct dentry		*dentry,
 	struct iattr		*iattr)
 {
@@ -1044,14 +1058,14 @@ xfs_vn_setattr(
 			return error;
 		}
 
-		error = xfs_vn_setattr_size(dentry, iattr);
+		error = xfs_vn_setattr_size(mnt_userns, dentry, iattr);
 		xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
 	} else {
 		trace_xfs_setattr(ip);
 
-		error = xfs_vn_change_ok(dentry, iattr);
+		error = xfs_vn_change_ok(mnt_userns, dentry, iattr);
 		if (!error)
-			error = xfs_setattr_nonsize(ip, iattr);
+			error = xfs_setattr_nonsize(mnt_userns, ip, iattr);
 	}
 
 	return error;
@@ -1122,11 +1136,12 @@ xfs_vn_fiemap(
 
 STATIC int
 xfs_vn_tmpfile(
-	struct inode	*dir,
-	struct dentry	*dentry,
-	umode_t		mode)
+	struct user_namespace	*mnt_userns,
+	struct inode		*dir,
+	struct dentry		*dentry,
+	umode_t			mode)
 {
-	return xfs_generic_create(dir, dentry, mode, 0, true);
+	return xfs_generic_create(mnt_userns, dir, dentry, mode, 0, true);
 }
 
 static const struct inode_operations xfs_inode_operations = {
diff --git a/fs/xfs/xfs_iops.h b/fs/xfs/xfs_iops.h
index 99ca745c1071..278949056048 100644
--- a/fs/xfs/xfs_iops.h
+++ b/fs/xfs/xfs_iops.h
@@ -14,6 +14,7 @@ extern const struct file_operations xfs_dir_file_operations;
 extern ssize_t xfs_vn_listxattr(struct dentry *, char *data, size_t size);
 
 extern void xfs_setattr_time(struct xfs_inode *ip, struct iattr *iattr);
-extern int xfs_vn_setattr_size(struct dentry *dentry, struct iattr *vap);
+int xfs_vn_setattr_size(struct user_namespace *mnt_userns,
+		struct dentry *dentry, struct iattr *vap);
 
 #endif /* __XFS_IOPS_H__ */
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index 16ca97a7ff00..ca310a125d1e 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -54,10 +54,12 @@ struct xfs_bstat_chunk {
 STATIC int
 xfs_bulkstat_one_int(
 	struct xfs_mount	*mp,
+	struct user_namespace	*mnt_userns,
 	struct xfs_trans	*tp,
 	xfs_ino_t		ino,
 	struct xfs_bstat_chunk	*bc)
 {
+	struct user_namespace	*sb_userns = mp->m_super->s_user_ns;
 	struct xfs_icdinode	*dic;		/* dinode core info pointer */
 	struct xfs_inode	*ip;		/* incore inode pointer */
 	struct inode		*inode;
@@ -86,8 +88,8 @@ xfs_bulkstat_one_int(
 	 */
 	buf->bs_projectid = ip->i_d.di_projid;
 	buf->bs_ino = ino;
-	buf->bs_uid = i_uid_read(inode);
-	buf->bs_gid = i_gid_read(inode);
+	buf->bs_uid = from_kuid(sb_userns, i_uid_into_mnt(mnt_userns, inode));
+	buf->bs_gid = from_kgid(sb_userns, i_gid_into_mnt(mnt_userns, inode));
 	buf->bs_size = dic->di_size;
 
 	buf->bs_nlink = inode->i_nlink;
@@ -173,7 +175,8 @@ xfs_bulkstat_one(
 	if (!bc.buf)
 		return -ENOMEM;
 
-	error = xfs_bulkstat_one_int(breq->mp, NULL, breq->startino, &bc);
+	error = xfs_bulkstat_one_int(breq->mp, breq->mnt_userns, NULL,
+				     breq->startino, &bc);
 
 	kmem_free(bc.buf);
 
@@ -194,9 +197,10 @@ xfs_bulkstat_iwalk(
 	xfs_ino_t		ino,
 	void			*data)
 {
+	struct xfs_bstat_chunk	*bc = data;
 	int			error;
 
-	error = xfs_bulkstat_one_int(mp, tp, ino, data);
+	error = xfs_bulkstat_one_int(mp, bc->breq->mnt_userns, tp, ino, data);
 	/* bulkstat just skips over missing inodes */
 	if (error == -ENOENT || error == -EINVAL)
 		return 0;
@@ -239,6 +243,11 @@ xfs_bulkstat(
 	};
 	int			error;
 
+	if (breq->mnt_userns != &init_user_ns) {
+		xfs_warn_ratelimited(breq->mp,
+			"bulkstat not supported inside of idmapped mounts.");
+		return -EINVAL;
+	}
 	if (xfs_bulkstat_already_done(breq->mp, breq->startino))
 		return 0;
 
diff --git a/fs/xfs/xfs_itable.h b/fs/xfs/xfs_itable.h
index 96a1e2a9be3f..7078d10c9b12 100644
--- a/fs/xfs/xfs_itable.h
+++ b/fs/xfs/xfs_itable.h
@@ -8,6 +8,7 @@
 /* In-memory representation of a userspace request for batch inode data. */
 struct xfs_ibulk {
 	struct xfs_mount	*mp;
+	struct user_namespace   *mnt_userns;
 	void __user		*ubuffer; /* user output buffer */
 	xfs_ino_t		startino; /* start with this inode */
 	unsigned int		icount;   /* number of elements in ubuffer */
diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index 742d1413e2d0..bfa4164990b1 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -787,7 +787,8 @@ xfs_qm_qino_alloc(
 		return error;
 
 	if (need_alloc) {
-		error = xfs_dir_ialloc(&tp, NULL, S_IFREG, 1, 0, 0, ipp);
+		error = xfs_dir_ialloc(&init_user_ns, &tp, NULL, S_IFREG, 1, 0,
+				       0, ipp);
 		if (error) {
 			xfs_trans_cancel(tp);
 			return error;
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 586d42342a79..e5e0713bebcd 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1881,7 +1881,7 @@ static struct file_system_type xfs_fs_type = {
 	.init_fs_context	= xfs_init_fs_context,
 	.parameters		= xfs_fs_parameters,
 	.kill_sb		= kill_block_super,
-	.fs_flags		= FS_REQUIRES_DEV,
+	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
 };
 MODULE_ALIAS_FS("xfs");
 
diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c
index 8565663b16cd..1379013d74b8 100644
--- a/fs/xfs/xfs_symlink.c
+++ b/fs/xfs/xfs_symlink.c
@@ -134,6 +134,7 @@ xfs_readlink(
 
 int
 xfs_symlink(
+	struct user_namespace	*mnt_userns,
 	struct xfs_inode	*dp,
 	struct xfs_name		*link_name,
 	const char		*target_path,
@@ -221,8 +222,8 @@ xfs_symlink(
 	/*
 	 * Allocate an inode for the symlink.
 	 */
-	error = xfs_dir_ialloc(&tp, dp, S_IFLNK | (mode & ~S_IFMT), 1, 0,
-			       prid, &ip);
+	error = xfs_dir_ialloc(mnt_userns, &tp, dp, S_IFLNK | (mode & ~S_IFMT),
+			       1, 0, prid, &ip);
 	if (error)
 		goto out_trans_cancel;
 
diff --git a/fs/xfs/xfs_symlink.h b/fs/xfs/xfs_symlink.h
index b1fa091427e6..2586b7e393f3 100644
--- a/fs/xfs/xfs_symlink.h
+++ b/fs/xfs/xfs_symlink.h
@@ -7,8 +7,9 @@
 
 /* Kernel only symlink definitions */
 
-int xfs_symlink(struct xfs_inode *dp, struct xfs_name *link_name,
-		const char *target_path, umode_t mode, struct xfs_inode **ipp);
+int xfs_symlink(struct user_namespace *mnt_userns, struct xfs_inode *dp,
+		struct xfs_name *link_name, const char *target_path,
+		umode_t mode, struct xfs_inode **ipp);
 int xfs_readlink_bmap_ilocked(struct xfs_inode *ip, char *link);
 int xfs_readlink(struct xfs_inode *ip, char *link);
 int xfs_inactive_symlink(struct xfs_inode *ip);
diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
index bca48b308c02..12be32f66dc1 100644
--- a/fs/xfs/xfs_xattr.c
+++ b/fs/xfs/xfs_xattr.c
@@ -38,9 +38,10 @@ xfs_xattr_get(const struct xattr_handler *handler, struct dentry *unused,
 }
 
 static int
-xfs_xattr_set(const struct xattr_handler *handler, struct dentry *unused,
-		struct inode *inode, const char *name, const void *value,
-		size_t size, int flags)
+xfs_xattr_set(const struct xattr_handler *handler,
+	      struct user_namespace *mnt_userns, struct dentry *unused,
+	      struct inode *inode, const char *name, const void *value,
+	      size_t size, int flags)
 {
 	struct xfs_da_args	args = {
 		.dp		= XFS_I(inode),
diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c
index f3115432b43a..b6ff4a21abac 100644
--- a/fs/zonefs/super.c
+++ b/fs/zonefs/super.c
@@ -489,7 +489,8 @@ unlock:
 	return ret;
 }
 
-static int zonefs_inode_setattr(struct dentry *dentry, struct iattr *iattr)
+static int zonefs_inode_setattr(struct user_namespace *mnt_userns,
+				struct dentry *dentry, struct iattr *iattr)
 {
 	struct inode *inode = d_inode(dentry);
 	int ret;
@@ -497,7 +498,7 @@ static int zonefs_inode_setattr(struct dentry *dentry, struct iattr *iattr)
 	if (unlikely(IS_IMMUTABLE(inode)))
 		return -EPERM;
 
-	ret = setattr_prepare(dentry, iattr);
+	ret = setattr_prepare(&init_user_ns, dentry, iattr);
 	if (ret)
 		return ret;
 
@@ -525,7 +526,7 @@ static int zonefs_inode_setattr(struct dentry *dentry, struct iattr *iattr)
 			return ret;
 	}
 
-	setattr_copy(inode, iattr);
+	setattr_copy(&init_user_ns, inode, iattr);
 
 	return 0;
 }
@@ -1233,7 +1234,7 @@ static void zonefs_init_dir_inode(struct inode *parent, struct inode *inode,
 	struct super_block *sb = parent->i_sb;
 
 	inode->i_ino = blkdev_nr_zones(sb->s_bdev->bd_disk) + type + 1;
-	inode_init_owner(inode, parent, S_IFDIR | 0555);
+	inode_init_owner(&init_user_ns, inode, parent, S_IFDIR | 0555);
 	inode->i_op = &zonefs_dir_inode_operations;
 	inode->i_fop = &simple_dir_operations;
 	set_nlink(inode, 2);
diff --git a/include/linux/capability.h b/include/linux/capability.h
index b2f698915c0f..65efb74c3585 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -247,8 +247,11 @@ static inline bool ns_capable_setid(struct user_namespace *ns, int cap)
 	return true;
 }
 #endif /* CONFIG_MULTIUSER */
-extern bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode);
-extern bool capable_wrt_inode_uidgid(const struct inode *inode, int cap);
+bool privileged_wrt_inode_uidgid(struct user_namespace *ns,
+				 struct user_namespace *mnt_userns,
+				 const struct inode *inode);
+bool capable_wrt_inode_uidgid(struct user_namespace *mnt_userns,
+			      const struct inode *inode, int cap);
 extern bool file_ns_capable(const struct file *file, struct user_namespace *ns, int cap);
 extern bool ptracer_capable(struct task_struct *tsk, struct user_namespace *ns);
 static inline bool perfmon_capable(void)
@@ -268,8 +271,11 @@ static inline bool checkpoint_restore_ns_capable(struct user_namespace *ns)
 }
 
 /* audit system wants to get cap info from files as well */
-extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps);
+int get_vfs_caps_from_disk(struct user_namespace *mnt_userns,
+			   const struct dentry *dentry,
+			   struct cpu_vfs_cap_data *cpu_caps);
 
-extern int cap_convert_nscap(struct dentry *dentry, const void **ivalue, size_t size);
+int cap_convert_nscap(struct user_namespace *mnt_userns, struct dentry *dentry,
+		      const void **ivalue, size_t size);
 
 #endif /* !_LINUX_CAPABILITY_H */
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 43ba79ddbd68..418b772d6eca 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -39,6 +39,8 @@
 #include <linux/fs_types.h>
 #include <linux/build_bug.h>
 #include <linux/stddef.h>
+#include <linux/mount.h>
+#include <linux/cred.h>
 
 #include <asm/byteorder.h>
 #include <uapi/linux/fs.h>
@@ -1572,6 +1574,52 @@ static inline void i_gid_write(struct inode *inode, gid_t gid)
 	inode->i_gid = make_kgid(inode->i_sb->s_user_ns, gid);
 }
 
+static inline kuid_t kuid_into_mnt(struct user_namespace *mnt_userns,
+				   kuid_t kuid)
+{
+	return make_kuid(mnt_userns, __kuid_val(kuid));
+}
+
+static inline kgid_t kgid_into_mnt(struct user_namespace *mnt_userns,
+				   kgid_t kgid)
+{
+	return make_kgid(mnt_userns, __kgid_val(kgid));
+}
+
+static inline kuid_t i_uid_into_mnt(struct user_namespace *mnt_userns,
+				    const struct inode *inode)
+{
+	return kuid_into_mnt(mnt_userns, inode->i_uid);
+}
+
+static inline kgid_t i_gid_into_mnt(struct user_namespace *mnt_userns,
+				    const struct inode *inode)
+{
+	return kgid_into_mnt(mnt_userns, inode->i_gid);
+}
+
+static inline kuid_t kuid_from_mnt(struct user_namespace *mnt_userns,
+				   kuid_t kuid)
+{
+	return KUIDT_INIT(from_kuid(mnt_userns, kuid));
+}
+
+static inline kgid_t kgid_from_mnt(struct user_namespace *mnt_userns,
+				   kgid_t kgid)
+{
+	return KGIDT_INIT(from_kgid(mnt_userns, kgid));
+}
+
+static inline kuid_t fsuid_into_mnt(struct user_namespace *mnt_userns)
+{
+	return kuid_from_mnt(mnt_userns, current_fsuid());
+}
+
+static inline kgid_t fsgid_into_mnt(struct user_namespace *mnt_userns)
+{
+	return kgid_from_mnt(mnt_userns, current_fsgid());
+}
+
 extern struct timespec64 current_time(struct inode *inode);
 
 /*
@@ -1714,28 +1762,48 @@ static inline bool sb_start_intwrite_trylock(struct super_block *sb)
 	return __sb_start_write_trylock(sb, SB_FREEZE_FS);
 }
 
-
-extern bool inode_owner_or_capable(const struct inode *inode);
+bool inode_owner_or_capable(struct user_namespace *mnt_userns,
+			    const struct inode *inode);
 
 /*
  * VFS helper functions..
  */
-extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
-extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
-extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
-extern int vfs_symlink(struct inode *, struct dentry *, const char *);
-extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
-extern int vfs_rmdir(struct inode *, struct dentry *);
-extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
-extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
+int vfs_create(struct user_namespace *, struct inode *,
+	       struct dentry *, umode_t, bool);
+int vfs_mkdir(struct user_namespace *, struct inode *,
+	      struct dentry *, umode_t);
+int vfs_mknod(struct user_namespace *, struct inode *, struct dentry *,
+              umode_t, dev_t);
+int vfs_symlink(struct user_namespace *, struct inode *,
+		struct dentry *, const char *);
+int vfs_link(struct dentry *, struct user_namespace *, struct inode *,
+	     struct dentry *, struct inode **);
+int vfs_rmdir(struct user_namespace *, struct inode *, struct dentry *);
+int vfs_unlink(struct user_namespace *, struct inode *, struct dentry *,
+	       struct inode **);
 
-static inline int vfs_whiteout(struct inode *dir, struct dentry *dentry)
+struct renamedata {
+	struct user_namespace *old_mnt_userns;
+	struct inode *old_dir;
+	struct dentry *old_dentry;
+	struct user_namespace *new_mnt_userns;
+	struct inode *new_dir;
+	struct dentry *new_dentry;
+	struct inode **delegated_inode;
+	unsigned int flags;
+} __randomize_layout;
+
+int vfs_rename(struct renamedata *);
+
+static inline int vfs_whiteout(struct user_namespace *mnt_userns,
+			       struct inode *dir, struct dentry *dentry)
 {
-	return vfs_mknod(dir, dentry, S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
+	return vfs_mknod(mnt_userns, dir, dentry, S_IFCHR | WHITEOUT_MODE,
+			 WHITEOUT_DEV);
 }
 
-extern struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode,
-				  int open_flag);
+struct dentry *vfs_tmpfile(struct user_namespace *mnt_userns,
+			   struct dentry *dentry, umode_t mode, int open_flag);
 
 int vfs_mkobj(struct dentry *, umode_t,
 		int (*f)(struct dentry *, umode_t, void *),
@@ -1757,8 +1825,8 @@ extern long compat_ptr_ioctl(struct file *file, unsigned int cmd,
 /*
  * VFS file helper functions.
  */
-extern void inode_init_owner(struct inode *inode, const struct inode *dir,
-			umode_t mode);
+void inode_init_owner(struct user_namespace *mnt_userns, struct inode *inode,
+		      const struct inode *dir, umode_t mode);
 extern bool may_open_dev(const struct path *path);
 
 /*
@@ -1862,22 +1930,28 @@ struct file_operations {
 struct inode_operations {
 	struct dentry * (*lookup) (struct inode *,struct dentry *, unsigned int);
 	const char * (*get_link) (struct dentry *, struct inode *, struct delayed_call *);
-	int (*permission) (struct inode *, int);
+	int (*permission) (struct user_namespace *, struct inode *, int);
 	struct posix_acl * (*get_acl)(struct inode *, int);
 
 	int (*readlink) (struct dentry *, char __user *,int);
 
-	int (*create) (struct inode *,struct dentry *, umode_t, bool);
+	int (*create) (struct user_namespace *, struct inode *,struct dentry *,
+		       umode_t, bool);
 	int (*link) (struct dentry *,struct inode *,struct dentry *);
 	int (*unlink) (struct inode *,struct dentry *);
-	int (*symlink) (struct inode *,struct dentry *,const char *);
-	int (*mkdir) (struct inode *,struct dentry *,umode_t);
+	int (*symlink) (struct user_namespace *, struct inode *,struct dentry *,
+			const char *);
+	int (*mkdir) (struct user_namespace *, struct inode *,struct dentry *,
+		      umode_t);
 	int (*rmdir) (struct inode *,struct dentry *);
-	int (*mknod) (struct inode *,struct dentry *,umode_t,dev_t);
-	int (*rename) (struct inode *, struct dentry *,
+	int (*mknod) (struct user_namespace *, struct inode *,struct dentry *,
+		      umode_t,dev_t);
+	int (*rename) (struct user_namespace *, struct inode *, struct dentry *,
 			struct inode *, struct dentry *, unsigned int);
-	int (*setattr) (struct dentry *, struct iattr *);
-	int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);
+	int (*setattr) (struct user_namespace *, struct dentry *,
+			struct iattr *);
+	int (*getattr) (struct user_namespace *, const struct path *,
+			struct kstat *, u32, unsigned int);
 	ssize_t (*listxattr) (struct dentry *, char *, size_t);
 	int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start,
 		      u64 len);
@@ -1885,8 +1959,10 @@ struct inode_operations {
 	int (*atomic_open)(struct inode *, struct dentry *,
 			   struct file *, unsigned open_flag,
 			   umode_t create_mode);
-	int (*tmpfile) (struct inode *, struct dentry *, umode_t);
-	int (*set_acl)(struct inode *, struct posix_acl *, int);
+	int (*tmpfile) (struct user_namespace *, struct inode *,
+			struct dentry *, umode_t);
+	int (*set_acl)(struct user_namespace *, struct inode *,
+		       struct posix_acl *, int);
 } ____cacheline_aligned;
 
 static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,
@@ -2035,9 +2111,11 @@ static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags
 #define IS_WHITEOUT(inode)	(S_ISCHR(inode->i_mode) && \
 				 (inode)->i_rdev == WHITEOUT_DEV)
 
-static inline bool HAS_UNMAPPED_ID(struct inode *inode)
+static inline bool HAS_UNMAPPED_ID(struct user_namespace *mnt_userns,
+				   struct inode *inode)
 {
-	return !uid_valid(inode->i_uid) || !gid_valid(inode->i_gid);
+	return !uid_valid(i_uid_into_mnt(mnt_userns, inode)) ||
+	       !gid_valid(i_gid_into_mnt(mnt_userns, inode));
 }
 
 static inline enum rw_hint file_write_hint(struct file *file)
@@ -2254,6 +2332,7 @@ struct file_system_type {
 #define FS_HAS_SUBTYPE		4
 #define FS_USERNS_MOUNT		8	/* Can be mounted by userns root */
 #define FS_DISALLOW_NOTIFY_PERM	16	/* Disable fanotify permission events */
+#define FS_ALLOW_IDMAP         32      /* FS has been updated to handle vfs idmappings. */
 #define FS_THP_SUPPORT		8192	/* Remove once all fs converted */
 #define FS_RENAME_DOES_D_MOVE	32768	/* FS will handle d_move() during rename() internally. */
 	int (*init_fs_context)(struct fs_context *);
@@ -2540,9 +2619,13 @@ struct filename {
 };
 static_assert(offsetof(struct filename, iname) % sizeof(long) == 0);
 
+static inline struct user_namespace *file_mnt_user_ns(struct file *file)
+{
+	return mnt_user_ns(file->f_path.mnt);
+}
 extern long vfs_truncate(const struct path *, loff_t);
-extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
-		       struct file *filp);
+int do_truncate(struct user_namespace *, struct dentry *, loff_t start,
+		unsigned int time_attrs, struct file *filp);
 extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
 			loff_t len);
 extern long do_sys_open(int dfd, const char __user *filename, int flags,
@@ -2779,10 +2862,22 @@ static inline int bmap(struct inode *inode,  sector_t *block)
 }
 #endif
 
-extern int notify_change(struct dentry *, struct iattr *, struct inode **);
-extern int inode_permission(struct inode *, int);
-extern int generic_permission(struct inode *, int);
-extern int __check_sticky(struct inode *dir, struct inode *inode);
+int notify_change(struct user_namespace *, struct dentry *,
+		  struct iattr *, struct inode **);
+int inode_permission(struct user_namespace *, struct inode *, int);
+int generic_permission(struct user_namespace *, struct inode *, int);
+static inline int file_permission(struct file *file, int mask)
+{
+	return inode_permission(file_mnt_user_ns(file),
+				file_inode(file), mask);
+}
+static inline int path_permission(const struct path *path, int mask)
+{
+	return inode_permission(mnt_user_ns(path->mnt),
+				d_inode(path->dentry), mask);
+}
+int __check_sticky(struct user_namespace *mnt_userns, struct inode *dir,
+		   struct inode *inode);
 
 static inline bool execute_ok(struct inode *inode)
 {
@@ -3113,7 +3208,7 @@ extern int __page_symlink(struct inode *inode, const char *symname, int len,
 extern int page_symlink(struct inode *inode, const char *symname, int len);
 extern const struct inode_operations page_symlink_inode_operations;
 extern void kfree_link(void *);
-extern void generic_fillattr(struct inode *, struct kstat *);
+void generic_fillattr(struct user_namespace *, struct inode *, struct kstat *);
 extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
 extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
 void __inode_add_bytes(struct inode *inode, loff_t bytes);
@@ -3163,15 +3258,18 @@ extern int dcache_dir_open(struct inode *, struct file *);
 extern int dcache_dir_close(struct inode *, struct file *);
 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
 extern int dcache_readdir(struct file *, struct dir_context *);
-extern int simple_setattr(struct dentry *, struct iattr *);
-extern int simple_getattr(const struct path *, struct kstat *, u32, unsigned int);
+extern int simple_setattr(struct user_namespace *, struct dentry *,
+			  struct iattr *);
+extern int simple_getattr(struct user_namespace *, const struct path *,
+			  struct kstat *, u32, unsigned int);
 extern int simple_statfs(struct dentry *, struct kstatfs *);
 extern int simple_open(struct inode *inode, struct file *file);
 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
 extern int simple_unlink(struct inode *, struct dentry *);
 extern int simple_rmdir(struct inode *, struct dentry *);
-extern int simple_rename(struct inode *, struct dentry *,
-			 struct inode *, struct dentry *, unsigned int);
+extern int simple_rename(struct user_namespace *, struct inode *,
+			 struct dentry *, struct inode *, struct dentry *,
+			 unsigned int);
 extern void simple_recursive_removal(struct dentry *,
                               void (*callback)(struct dentry *));
 extern int noop_fsync(struct file *, loff_t, loff_t, int);
@@ -3229,9 +3327,10 @@ extern int buffer_migrate_page_norefs(struct address_space *,
 #define buffer_migrate_page_norefs NULL
 #endif
 
-extern int setattr_prepare(struct dentry *, struct iattr *);
+int setattr_prepare(struct user_namespace *, struct dentry *, struct iattr *);
 extern int inode_newsize_ok(const struct inode *, loff_t offset);
-extern void setattr_copy(struct inode *inode, const struct iattr *attr);
+void setattr_copy(struct user_namespace *, struct inode *inode,
+		  const struct iattr *attr);
 
 extern int file_update_time(struct file *file);
 
@@ -3395,12 +3494,13 @@ static inline bool is_sxid(umode_t mode)
 	return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
 }
 
-static inline int check_sticky(struct inode *dir, struct inode *inode)
+static inline int check_sticky(struct user_namespace *mnt_userns,
+			       struct inode *dir, struct inode *inode)
 {
 	if (!(dir->i_mode & S_ISVTX))
 		return 0;
 
-	return __check_sticky(dir, inode);
+	return __check_sticky(mnt_userns, dir, inode);
 }
 
 static inline void inode_has_no_xattr(struct inode *inode)
diff --git a/include/linux/ima.h b/include/linux/ima.h
index 2ac834badbbe..61d5723ec303 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -16,7 +16,8 @@ struct linux_binprm;
 #ifdef CONFIG_IMA
 extern int ima_bprm_check(struct linux_binprm *bprm);
 extern int ima_file_check(struct file *file, int mask);
-extern void ima_post_create_tmpfile(struct inode *inode);
+extern void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
+				    struct inode *inode);
 extern void ima_file_free(struct file *file);
 extern int ima_file_mmap(struct file *file, unsigned long prot);
 extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot);
@@ -27,7 +28,8 @@ extern int ima_read_file(struct file *file, enum kernel_read_file_id id,
 			 bool contents);
 extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
 			      enum kernel_read_file_id id);
-extern void ima_post_path_mknod(struct dentry *dentry);
+extern void ima_post_path_mknod(struct user_namespace *mnt_userns,
+				struct dentry *dentry);
 extern int ima_file_hash(struct file *file, char *buf, size_t buf_size);
 extern int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size);
 extern void ima_kexec_cmdline(int kernel_fd, const void *buf, int size);
@@ -72,7 +74,8 @@ static inline int ima_file_check(struct file *file, int mask)
 	return 0;
 }
 
-static inline void ima_post_create_tmpfile(struct inode *inode)
+static inline void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
+					   struct inode *inode)
 {
 }
 
@@ -116,7 +119,8 @@ static inline int ima_post_read_file(struct file *file, void *buf, loff_t size,
 	return 0;
 }
 
-static inline void ima_post_path_mknod(struct dentry *dentry)
+static inline void ima_post_path_mknod(struct user_namespace *mnt_userns,
+				       struct dentry *dentry)
 {
 	return;
 }
@@ -163,7 +167,8 @@ static inline void ima_post_key_create_or_update(struct key *keyring,
 
 #ifdef CONFIG_IMA_APPRAISE
 extern bool is_ima_appraise_enabled(void);
-extern void ima_inode_post_setattr(struct dentry *dentry);
+extern void ima_inode_post_setattr(struct user_namespace *mnt_userns,
+				   struct dentry *dentry);
 extern int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
 		       const void *xattr_value, size_t xattr_value_len);
 extern int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name);
@@ -173,7 +178,8 @@ static inline bool is_ima_appraise_enabled(void)
 	return 0;
 }
 
-static inline void ima_inode_post_setattr(struct dentry *dentry)
+static inline void ima_inode_post_setattr(struct user_namespace *mnt_userns,
+					  struct dentry *dentry)
 {
 	return;
 }
diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index dfd261dcbcb0..477a597db013 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h
@@ -135,17 +135,20 @@ LSM_HOOK(int, 0, inode_follow_link, struct dentry *dentry, struct inode *inode,
 LSM_HOOK(int, 0, inode_permission, struct inode *inode, int mask)
 LSM_HOOK(int, 0, inode_setattr, struct dentry *dentry, struct iattr *attr)
 LSM_HOOK(int, 0, inode_getattr, const struct path *path)
-LSM_HOOK(int, 0, inode_setxattr, struct dentry *dentry, const char *name,
-	 const void *value, size_t size, int flags)
+LSM_HOOK(int, 0, inode_setxattr, struct user_namespace *mnt_userns,
+	 struct dentry *dentry, const char *name, const void *value,
+	 size_t size, int flags)
 LSM_HOOK(void, LSM_RET_VOID, inode_post_setxattr, struct dentry *dentry,
 	 const char *name, const void *value, size_t size, int flags)
 LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name)
 LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry)
-LSM_HOOK(int, 0, inode_removexattr, struct dentry *dentry, const char *name)
+LSM_HOOK(int, 0, inode_removexattr, struct user_namespace *mnt_userns,
+	 struct dentry *dentry, const char *name)
 LSM_HOOK(int, 0, inode_need_killpriv, struct dentry *dentry)
-LSM_HOOK(int, 0, inode_killpriv, struct dentry *dentry)
-LSM_HOOK(int, -EOPNOTSUPP, inode_getsecurity, struct inode *inode,
-	 const char *name, void **buffer, bool alloc)
+LSM_HOOK(int, 0, inode_killpriv, struct user_namespace *mnt_userns,
+	 struct dentry *dentry)
+LSM_HOOK(int, -EOPNOTSUPP, inode_getsecurity, struct user_namespace *mnt_userns,
+	 struct inode *inode, const char *name, void **buffer, bool alloc)
 LSM_HOOK(int, -EOPNOTSUPP, inode_setsecurity, struct inode *inode,
 	 const char *name, const void *value, size_t size, int flags)
 LSM_HOOK(int, 0, inode_listsecurity, struct inode *inode, char *buffer,
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index bdfc8a76a4f7..fb7f3193753d 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -453,6 +453,7 @@
  * @inode_killpriv:
  *	The setuid bit is being removed.  Remove similar security labels.
  *	Called with the dentry->d_inode->i_mutex held.
+ *	@mnt_userns: user namespace of the mount
  *	@dentry is the dentry being changed.
  *	Return 0 on success.  If error is returned, then the operation
  *	causing setuid bit removal is failed.
diff --git a/include/linux/mount.h b/include/linux/mount.h
index aaf343b38671..161f4419db6c 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -72,8 +72,15 @@ struct vfsmount {
 	struct dentry *mnt_root;	/* root of the mounted tree */
 	struct super_block *mnt_sb;	/* pointer to superblock */
 	int mnt_flags;
+	struct user_namespace *mnt_userns;
 } __randomize_layout;
 
+static inline struct user_namespace *mnt_user_ns(const struct vfsmount *mnt)
+{
+	/* Pairs with smp_store_release() in do_idmap_mount(). */
+	return smp_load_acquire(&mnt->mnt_userns);
+}
+
 struct file; /* forward dec */
 struct path;
 
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 681ed98e4ba8..8c6c4e32fc2f 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -379,10 +379,11 @@ extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
 extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
 extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
 extern int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr);
-extern int nfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
+extern int nfs_getattr(struct user_namespace *, const struct path *,
+		       struct kstat *, u32, unsigned int);
 extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
 extern void nfs_access_set_mask(struct nfs_access_entry *, u32);
-extern int nfs_permission(struct inode *, int);
+extern int nfs_permission(struct user_namespace *, struct inode *, int);
 extern int nfs_open(struct inode *, struct file *);
 extern int nfs_attribute_cache_expired(struct inode *inode);
 extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
@@ -390,7 +391,7 @@ extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
 extern bool nfs_mapping_need_revalidate_inode(struct inode *inode);
 extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
 extern int nfs_revalidate_mapping_rcu(struct inode *inode);
-extern int nfs_setattr(struct dentry *, struct iattr *);
+extern int nfs_setattr(struct user_namespace *, struct dentry *, struct iattr *);
 extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr, struct nfs_fattr *);
 extern void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
 				struct nfs4_label *label);
diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index 90797f1b421d..307094ebb88c 100644
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -15,6 +15,8 @@
 #include <linux/refcount.h>
 #include <uapi/linux/posix_acl.h>
 
+struct user_namespace;
+
 struct posix_acl_entry {
 	short			e_tag;
 	unsigned short		e_perm;
@@ -61,23 +63,24 @@ posix_acl_release(struct posix_acl *acl)
 
 extern void posix_acl_init(struct posix_acl *, int);
 extern struct posix_acl *posix_acl_alloc(int, gfp_t);
-extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *);
-extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
 extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
 extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
 extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
 extern int __posix_acl_chmod(struct posix_acl **, gfp_t, umode_t);
 
 extern struct posix_acl *get_posix_acl(struct inode *, int);
-extern int set_posix_acl(struct inode *, int, struct posix_acl *);
+extern int set_posix_acl(struct user_namespace *, struct inode *, int,
+			 struct posix_acl *);
 
 #ifdef CONFIG_FS_POSIX_ACL
-extern int posix_acl_chmod(struct inode *, umode_t);
+int posix_acl_chmod(struct user_namespace *, struct inode *, umode_t);
 extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **,
 		struct posix_acl **);
-extern int posix_acl_update_mode(struct inode *, umode_t *, struct posix_acl **);
+int posix_acl_update_mode(struct user_namespace *, struct inode *, umode_t *,
+			  struct posix_acl **);
 
-extern int simple_set_acl(struct inode *, struct posix_acl *, int);
+extern int simple_set_acl(struct user_namespace *, struct inode *,
+			  struct posix_acl *, int);
 extern int simple_acl_create(struct inode *, struct inode *);
 
 struct posix_acl *get_cached_acl(struct inode *inode, int type);
@@ -85,6 +88,9 @@ struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type);
 void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl);
 void forget_cached_acl(struct inode *inode, int type);
 void forget_all_cached_acls(struct inode *inode);
+int posix_acl_valid(struct user_namespace *, const struct posix_acl *);
+int posix_acl_permission(struct user_namespace *, struct inode *,
+			 const struct posix_acl *, int);
 
 static inline void cache_no_acl(struct inode *inode)
 {
@@ -92,7 +98,8 @@ static inline void cache_no_acl(struct inode *inode)
 	inode->i_default_acl = NULL;
 }
 #else
-static inline int posix_acl_chmod(struct inode *inode, umode_t mode)
+static inline int posix_acl_chmod(struct user_namespace *mnt_userns,
+				  struct inode *inode, umode_t mode)
 {
 	return 0;
 }
diff --git a/include/linux/posix_acl_xattr.h b/include/linux/posix_acl_xattr.h
index 2387709991b5..060e8d203181 100644
--- a/include/linux/posix_acl_xattr.h
+++ b/include/linux/posix_acl_xattr.h
@@ -33,13 +33,17 @@ posix_acl_xattr_count(size_t size)
 }
 
 #ifdef CONFIG_FS_POSIX_ACL
-void posix_acl_fix_xattr_from_user(void *value, size_t size);
-void posix_acl_fix_xattr_to_user(void *value, size_t size);
+void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
+				   void *value, size_t size);
+void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
+				 void *value, size_t size);
 #else
-static inline void posix_acl_fix_xattr_from_user(void *value, size_t size)
+static inline void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
+						 void *value, size_t size)
 {
 }
-static inline void posix_acl_fix_xattr_to_user(void *value, size_t size)
+static inline void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
+					       void *value, size_t size)
 {
 }
 #endif
diff --git a/include/linux/security.h b/include/linux/security.h
index b0d14f04b16d..8aeebd6646dc 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -145,13 +145,16 @@ extern int cap_capset(struct cred *new, const struct cred *old,
 		      const kernel_cap_t *inheritable,
 		      const kernel_cap_t *permitted);
 extern int cap_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file);
-extern int cap_inode_setxattr(struct dentry *dentry, const char *name,
-			      const void *value, size_t size, int flags);
-extern int cap_inode_removexattr(struct dentry *dentry, const char *name);
-extern int cap_inode_need_killpriv(struct dentry *dentry);
-extern int cap_inode_killpriv(struct dentry *dentry);
-extern int cap_inode_getsecurity(struct inode *inode, const char *name,
-				 void **buffer, bool alloc);
+int cap_inode_setxattr(struct dentry *dentry, const char *name,
+		       const void *value, size_t size, int flags);
+int cap_inode_removexattr(struct user_namespace *mnt_userns,
+			  struct dentry *dentry, const char *name);
+int cap_inode_need_killpriv(struct dentry *dentry);
+int cap_inode_killpriv(struct user_namespace *mnt_userns,
+		       struct dentry *dentry);
+int cap_inode_getsecurity(struct user_namespace *mnt_userns,
+			  struct inode *inode, const char *name, void **buffer,
+			  bool alloc);
 extern int cap_mmap_addr(unsigned long addr);
 extern int cap_mmap_file(struct file *file, unsigned long reqprot,
 			 unsigned long prot, unsigned long flags);
@@ -348,16 +351,21 @@ int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
 int security_inode_permission(struct inode *inode, int mask);
 int security_inode_setattr(struct dentry *dentry, struct iattr *attr);
 int security_inode_getattr(const struct path *path);
-int security_inode_setxattr(struct dentry *dentry, const char *name,
+int security_inode_setxattr(struct user_namespace *mnt_userns,
+			    struct dentry *dentry, const char *name,
 			    const void *value, size_t size, int flags);
 void security_inode_post_setxattr(struct dentry *dentry, const char *name,
 				  const void *value, size_t size, int flags);
 int security_inode_getxattr(struct dentry *dentry, const char *name);
 int security_inode_listxattr(struct dentry *dentry);
-int security_inode_removexattr(struct dentry *dentry, const char *name);
+int security_inode_removexattr(struct user_namespace *mnt_userns,
+			       struct dentry *dentry, const char *name);
 int security_inode_need_killpriv(struct dentry *dentry);
-int security_inode_killpriv(struct dentry *dentry);
-int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc);
+int security_inode_killpriv(struct user_namespace *mnt_userns,
+			    struct dentry *dentry);
+int security_inode_getsecurity(struct user_namespace *mnt_userns,
+			       struct inode *inode, const char *name,
+			       void **buffer, bool alloc);
 int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags);
 int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size);
 void security_inode_getsecid(struct inode *inode, u32 *secid);
@@ -841,8 +849,9 @@ static inline int security_inode_getattr(const struct path *path)
 	return 0;
 }
 
-static inline int security_inode_setxattr(struct dentry *dentry,
-		const char *name, const void *value, size_t size, int flags)
+static inline int security_inode_setxattr(struct user_namespace *mnt_userns,
+		struct dentry *dentry, const char *name, const void *value,
+		size_t size, int flags)
 {
 	return cap_inode_setxattr(dentry, name, value, size, flags);
 }
@@ -862,10 +871,11 @@ static inline int security_inode_listxattr(struct dentry *dentry)
 	return 0;
 }
 
-static inline int security_inode_removexattr(struct dentry *dentry,
-			const char *name)
+static inline int security_inode_removexattr(struct user_namespace *mnt_userns,
+					     struct dentry *dentry,
+					     const char *name)
 {
-	return cap_inode_removexattr(dentry, name);
+	return cap_inode_removexattr(mnt_userns, dentry, name);
 }
 
 static inline int security_inode_need_killpriv(struct dentry *dentry)
@@ -873,14 +883,18 @@ static inline int security_inode_need_killpriv(struct dentry *dentry)
 	return cap_inode_need_killpriv(dentry);
 }
 
-static inline int security_inode_killpriv(struct dentry *dentry)
+static inline int security_inode_killpriv(struct user_namespace *mnt_userns,
+					  struct dentry *dentry)
 {
-	return cap_inode_killpriv(dentry);
+	return cap_inode_killpriv(mnt_userns, dentry);
 }
 
-static inline int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
+static inline int security_inode_getsecurity(struct user_namespace *mnt_userns,
+					     struct inode *inode,
+					     const char *name, void **buffer,
+					     bool alloc)
 {
-	return cap_inode_getsecurity(inode, name, buffer, alloc);
+	return cap_inode_getsecurity(mnt_userns, inode, name, buffer, alloc);
 }
 
 static inline int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags)
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index f93f9276d848..2839dc9a7c01 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -68,6 +68,7 @@ union bpf_attr;
 struct io_uring_params;
 struct clone_args;
 struct open_how;
+struct mount_attr;
 
 #include <linux/types.h>
 #include <linux/aio_abi.h>
@@ -1028,6 +1029,9 @@ asmlinkage long sys_open_tree(int dfd, const char __user *path, unsigned flags);
 asmlinkage long sys_move_mount(int from_dfd, const char __user *from_path,
 			       int to_dfd, const char __user *to_path,
 			       unsigned int ms_flags);
+asmlinkage long sys_mount_setattr(int dfd, const char __user *path,
+				  unsigned int flags,
+				  struct mount_attr __user *uattr, size_t usize);
 asmlinkage long sys_fsopen(const char __user *fs_name, unsigned int flags);
 asmlinkage long sys_fsconfig(int fs_fd, unsigned int cmd, const char __user *key,
 			     const void __user *value, int aux);
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index 10b4dc2709f0..4c379d23ec6e 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -16,6 +16,7 @@
 #include <linux/types.h>
 #include <linux/spinlock.h>
 #include <linux/mm.h>
+#include <linux/user_namespace.h>
 #include <uapi/linux/xattr.h>
 
 struct inode;
@@ -34,7 +35,8 @@ struct xattr_handler {
 	int (*get)(const struct xattr_handler *, struct dentry *dentry,
 		   struct inode *inode, const char *name, void *buffer,
 		   size_t size);
-	int (*set)(const struct xattr_handler *, struct dentry *dentry,
+	int (*set)(const struct xattr_handler *,
+		   struct user_namespace *mnt_userns, struct dentry *dentry,
 		   struct inode *inode, const char *name, const void *buffer,
 		   size_t size, int flags);
 };
@@ -48,18 +50,26 @@ struct xattr {
 };
 
 ssize_t __vfs_getxattr(struct dentry *, struct inode *, const char *, void *, size_t);
-ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
+ssize_t vfs_getxattr(struct user_namespace *, struct dentry *, const char *,
+		     void *, size_t);
 ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
-int __vfs_setxattr(struct dentry *, struct inode *, const char *, const void *, size_t, int);
-int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);
-int __vfs_setxattr_locked(struct dentry *, const char *, const void *, size_t, int, struct inode **);
-int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);
-int __vfs_removexattr(struct dentry *, const char *);
-int __vfs_removexattr_locked(struct dentry *, const char *, struct inode **);
-int vfs_removexattr(struct dentry *, const char *);
+int __vfs_setxattr(struct user_namespace *, struct dentry *, struct inode *,
+		   const char *, const void *, size_t, int);
+int __vfs_setxattr_noperm(struct user_namespace *, struct dentry *,
+			  const char *, const void *, size_t, int);
+int __vfs_setxattr_locked(struct user_namespace *, struct dentry *,
+			  const char *, const void *, size_t, int,
+			  struct inode **);
+int vfs_setxattr(struct user_namespace *, struct dentry *, const char *,
+		 const void *, size_t, int);
+int __vfs_removexattr(struct user_namespace *, struct dentry *, const char *);
+int __vfs_removexattr_locked(struct user_namespace *, struct dentry *,
+			     const char *, struct inode **);
+int vfs_removexattr(struct user_namespace *, struct dentry *, const char *);
 
 ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);
-ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name,
+ssize_t vfs_getxattr_alloc(struct user_namespace *mnt_userns,
+			   struct dentry *dentry, const char *name,
 			   char **xattr_value, size_t size, gfp_t flags);
 
 int xattr_supported_namespace(struct inode *inode, const char *prefix);
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 728752917785..ce58cff99b66 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -861,9 +861,11 @@ __SYSCALL(__NR_faccessat2, sys_faccessat2)
 __SYSCALL(__NR_process_madvise, sys_process_madvise)
 #define __NR_epoll_pwait2 441
 __SC_COMP(__NR_epoll_pwait2, sys_epoll_pwait2, compat_sys_epoll_pwait2)
+#define __NR_mount_setattr 442
+__SYSCALL(__NR_mount_setattr, sys_mount_setattr)
 
 #undef __NR_syscalls
-#define __NR_syscalls 442
+#define __NR_syscalls 443
 
 /*
  * 32 bit systems traditionally used different
diff --git a/include/uapi/linux/mount.h b/include/uapi/linux/mount.h
index dd8306ea336c..e6524ead2b7b 100644
--- a/include/uapi/linux/mount.h
+++ b/include/uapi/linux/mount.h
@@ -1,6 +1,8 @@
 #ifndef _UAPI_LINUX_MOUNT_H
 #define _UAPI_LINUX_MOUNT_H
 
+#include <linux/types.h>
+
 /*
  * These are the fs-independent mount-flags: up to 32 flags are supported
  *
@@ -117,5 +119,19 @@ enum fsconfig_command {
 #define MOUNT_ATTR_NOATIME	0x00000010 /* - Do not update access times. */
 #define MOUNT_ATTR_STRICTATIME	0x00000020 /* - Always perform atime updates */
 #define MOUNT_ATTR_NODIRATIME	0x00000080 /* Do not update directory access times */
+#define MOUNT_ATTR_IDMAP	0x00100000 /* Idmap mount to @userns_fd in struct mount_attr. */
+
+/*
+ * mount_setattr()
+ */
+struct mount_attr {
+	__u64 attr_set;
+	__u64 attr_clr;
+	__u64 propagation;
+	__u64 userns_fd;
+};
+
+/* List of all mount_attr versions. */
+#define MOUNT_ATTR_SIZE_VER0	32 /* sizeof first published struct */
 
 #endif /* _UAPI_LINUX_MOUNT_H */
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index beff0cfcd1e8..8031464ed4ae 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -594,8 +594,8 @@ out_unlock:
 	return error;
 }
 
-static int mqueue_create(struct inode *dir, struct dentry *dentry,
-				umode_t mode, bool excl)
+static int mqueue_create(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, umode_t mode, bool excl)
 {
 	return mqueue_create_attr(dentry, mode, NULL);
 }
@@ -873,7 +873,7 @@ static int prepare_open(struct dentry *dentry, int oflag, int ro,
 	if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY))
 		return -EINVAL;
 	acc = oflag2acc[oflag & O_ACCMODE];
-	return inode_permission(d_inode(dentry), acc);
+	return inode_permission(&init_user_ns, d_inode(dentry), acc);
 }
 
 static int do_mq_open(const char __user *u_name, int oflag, umode_t mode,
@@ -965,7 +965,8 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
 		err = -ENOENT;
 	} else {
 		ihold(inode);
-		err = vfs_unlink(d_inode(dentry->d_parent), dentry, NULL);
+		err = vfs_unlink(&init_user_ns, d_inode(dentry->d_parent),
+				 dentry, NULL);
 	}
 	dput(dentry);
 
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 434337ab6b2b..47fb48f42c93 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1930,7 +1930,7 @@ static inline int audit_copy_fcaps(struct audit_names *name,
 	if (!dentry)
 		return 0;
 
-	rc = get_vfs_caps_from_disk(dentry, &caps);
+	rc = get_vfs_caps_from_disk(&init_user_ns, dentry, &caps);
 	if (rc)
 		return rc;
 
@@ -2481,7 +2481,8 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
 	ax->d.next = context->aux;
 	context->aux = (void *)ax;
 
-	get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps);
+	get_vfs_caps_from_disk(&init_user_ns,
+			       bprm->file->f_path.dentry, &vcaps);
 
 	ax->fcap.permitted = vcaps.permitted;
 	ax->fcap.inheritable = vcaps.inheritable;
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index dd4b7fd60ee7..1576ff331ee4 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -122,7 +122,7 @@ static struct inode *bpf_get_inode(struct super_block *sb,
 	inode->i_mtime = inode->i_atime;
 	inode->i_ctime = inode->i_atime;
 
-	inode_init_owner(inode, dir, mode);
+	inode_init_owner(&init_user_ns, inode, dir, mode);
 
 	return inode;
 }
@@ -152,7 +152,8 @@ static void bpf_dentry_finalize(struct dentry *dentry, struct inode *inode,
 	dir->i_ctime = dir->i_mtime;
 }
 
-static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int bpf_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		     struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode;
 
@@ -381,8 +382,8 @@ bpf_lookup(struct inode *dir, struct dentry *dentry, unsigned flags)
 	return simple_lookup(dir, dentry, flags);
 }
 
-static int bpf_symlink(struct inode *dir, struct dentry *dentry,
-		       const char *target)
+static int bpf_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, const char *target)
 {
 	char *link = kstrdup(target, GFP_USER | __GFP_NOWARN);
 	struct inode *inode;
@@ -507,7 +508,7 @@ static void *bpf_obj_do_get(const char __user *pathname,
 		return ERR_PTR(ret);
 
 	inode = d_backing_inode(path.dentry);
-	ret = inode_permission(inode, ACC_MODE(flags));
+	ret = path_permission(&path, ACC_MODE(flags));
 	if (ret)
 		goto out;
 
@@ -558,7 +559,7 @@ int bpf_obj_get_user(const char __user *pathname, int flags)
 static struct bpf_prog *__get_prog_inode(struct inode *inode, enum bpf_prog_type type)
 {
 	struct bpf_prog *prog;
-	int ret = inode_permission(inode, MAY_READ);
+	int ret = inode_permission(&init_user_ns, inode, MAY_READ);
 	if (ret)
 		return ERR_PTR(ret);
 
diff --git a/kernel/capability.c b/kernel/capability.c
index de7eac903a2a..46a361dde042 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -484,10 +484,12 @@ EXPORT_SYMBOL(file_ns_capable);
  *
  * Return true if the inode uid and gid are within the namespace.
  */
-bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode)
+bool privileged_wrt_inode_uidgid(struct user_namespace *ns,
+				 struct user_namespace *mnt_userns,
+				 const struct inode *inode)
 {
-	return kuid_has_mapping(ns, inode->i_uid) &&
-		kgid_has_mapping(ns, inode->i_gid);
+	return kuid_has_mapping(ns, i_uid_into_mnt(mnt_userns, inode)) &&
+	       kgid_has_mapping(ns, i_gid_into_mnt(mnt_userns, inode));
 }
 
 /**
@@ -499,11 +501,13 @@ bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *
  * its own user namespace and that the given inode's uid and gid are
  * mapped into the current user namespace.
  */
-bool capable_wrt_inode_uidgid(const struct inode *inode, int cap)
+bool capable_wrt_inode_uidgid(struct user_namespace *mnt_userns,
+			      const struct inode *inode, int cap)
 {
 	struct user_namespace *ns = current_user_ns();
 
-	return ns_capable(ns, cap) && privileged_wrt_inode_uidgid(ns, inode);
+	return ns_capable(ns, cap) &&
+	       privileged_wrt_inode_uidgid(ns, mnt_userns, inode);
 }
 EXPORT_SYMBOL(capable_wrt_inode_uidgid);
 
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index c80fe99f85ae..9153b20e5cc6 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -4672,7 +4672,7 @@ static int cgroup_may_write(const struct cgroup *cgrp, struct super_block *sb)
 	if (!inode)
 		return -ENOMEM;
 
-	ret = inode_permission(inode, MAY_WRITE);
+	ret = inode_permission(&init_user_ns, inode, MAY_WRITE);
 	iput(inode);
 	return ret;
 }
diff --git a/kernel/sys.c b/kernel/sys.c
index 6928d23c46ea..8bb46e50f02d 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1847,7 +1847,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
 	if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
 		goto exit;
 
-	err = inode_permission(inode, MAY_EXEC);
+	err = file_permission(exe.file, MAY_EXEC);
 	if (err)
 		goto exit;
 
diff --git a/mm/madvise.c b/mm/madvise.c
index 0938fd3ad228..df692d2e35d4 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -539,8 +539,9 @@ static inline bool can_do_pageout(struct vm_area_struct *vma)
 	 * otherwise we'd be including shared non-exclusive mappings, which
 	 * opens a side channel.
 	 */
-	return inode_owner_or_capable(file_inode(vma->vm_file)) ||
-		inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
+	return inode_owner_or_capable(&init_user_ns,
+				      file_inode(vma->vm_file)) ||
+	       file_permission(vma->vm_file, MAY_WRITE) == 0;
 }
 
 static long madvise_pageout(struct vm_area_struct *vma,
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 913c2b9e5c72..0b9bd354e97e 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4897,7 +4897,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
 
 	/* the process need read permission on control file */
 	/* AV: shouldn't we check that it's been opened for read instead? */
-	ret = inode_permission(file_inode(cfile.file), MAY_READ);
+	ret = file_permission(cfile.file, MAY_READ);
 	if (ret < 0)
 		goto out_put_cfile;
 
diff --git a/mm/mincore.c b/mm/mincore.c
index 02db1a834021..9122676b54d6 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -166,8 +166,9 @@ static inline bool can_do_mincore(struct vm_area_struct *vma)
 	 * for writing; otherwise we'd be including shared non-exclusive
 	 * mappings, which opens a side channel.
 	 */
-	return inode_owner_or_capable(file_inode(vma->vm_file)) ||
-		inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
+	return inode_owner_or_capable(&init_user_ns,
+				      file_inode(vma->vm_file)) ||
+	       file_permission(vma->vm_file, MAY_WRITE) == 0;
 }
 
 static const struct mm_walk_ops mincore_walk_ops = {
diff --git a/mm/shmem.c b/mm/shmem.c
index 1b254fbfdf52..7924b3bf46fb 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1060,7 +1060,8 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
 }
 EXPORT_SYMBOL_GPL(shmem_truncate_range);
 
-static int shmem_getattr(const struct path *path, struct kstat *stat,
+static int shmem_getattr(struct user_namespace *mnt_userns,
+			 const struct path *path, struct kstat *stat,
 			 u32 request_mask, unsigned int query_flags)
 {
 	struct inode *inode = path->dentry->d_inode;
@@ -1072,7 +1073,7 @@ static int shmem_getattr(const struct path *path, struct kstat *stat,
 		shmem_recalc_inode(inode);
 		spin_unlock_irq(&info->lock);
 	}
-	generic_fillattr(inode, stat);
+	generic_fillattr(&init_user_ns, inode, stat);
 
 	if (is_huge_enabled(sb_info))
 		stat->blksize = HPAGE_PMD_SIZE;
@@ -1080,14 +1081,15 @@ static int shmem_getattr(const struct path *path, struct kstat *stat,
 	return 0;
 }
 
-static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
+static int shmem_setattr(struct user_namespace *mnt_userns,
+			 struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
 	struct shmem_inode_info *info = SHMEM_I(inode);
 	struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
 	int error;
 
-	error = setattr_prepare(dentry, attr);
+	error = setattr_prepare(&init_user_ns, dentry, attr);
 	if (error)
 		return error;
 
@@ -1141,9 +1143,9 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
 		}
 	}
 
-	setattr_copy(inode, attr);
+	setattr_copy(&init_user_ns, inode, attr);
 	if (attr->ia_valid & ATTR_MODE)
-		error = posix_acl_chmod(inode, inode->i_mode);
+		error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
 	return error;
 }
 
@@ -2303,7 +2305,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
 	inode = new_inode(sb);
 	if (inode) {
 		inode->i_ino = ino;
-		inode_init_owner(inode, dir, mode);
+		inode_init_owner(&init_user_ns, inode, dir, mode);
 		inode->i_blocks = 0;
 		inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
 		inode->i_generation = prandom_u32();
@@ -2917,7 +2919,8 @@ static int shmem_statfs(struct dentry *dentry, struct kstatfs *buf)
  * File creation. Allocate an inode, and we're done..
  */
 static int
-shmem_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+shmem_mknod(struct user_namespace *mnt_userns, struct inode *dir,
+	    struct dentry *dentry, umode_t mode, dev_t dev)
 {
 	struct inode *inode;
 	int error = -ENOSPC;
@@ -2946,7 +2949,8 @@ out_iput:
 }
 
 static int
-shmem_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+shmem_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
+	      struct dentry *dentry, umode_t mode)
 {
 	struct inode *inode;
 	int error = -ENOSPC;
@@ -2969,20 +2973,22 @@ out_iput:
 	return error;
 }
 
-static int shmem_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int shmem_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	int error;
 
-	if ((error = shmem_mknod(dir, dentry, mode | S_IFDIR, 0)))
+	if ((error = shmem_mknod(&init_user_ns, dir, dentry,
+				 mode | S_IFDIR, 0)))
 		return error;
 	inc_nlink(dir);
 	return 0;
 }
 
-static int shmem_create(struct inode *dir, struct dentry *dentry, umode_t mode,
-		bool excl)
+static int shmem_create(struct user_namespace *mnt_userns, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
 {
-	return shmem_mknod(dir, dentry, mode | S_IFREG, 0);
+	return shmem_mknod(&init_user_ns, dir, dentry, mode | S_IFREG, 0);
 }
 
 /*
@@ -3062,7 +3068,8 @@ static int shmem_exchange(struct inode *old_dir, struct dentry *old_dentry, stru
 	return 0;
 }
 
-static int shmem_whiteout(struct inode *old_dir, struct dentry *old_dentry)
+static int shmem_whiteout(struct user_namespace *mnt_userns,
+			  struct inode *old_dir, struct dentry *old_dentry)
 {
 	struct dentry *whiteout;
 	int error;
@@ -3071,7 +3078,7 @@ static int shmem_whiteout(struct inode *old_dir, struct dentry *old_dentry)
 	if (!whiteout)
 		return -ENOMEM;
 
-	error = shmem_mknod(old_dir, whiteout,
+	error = shmem_mknod(&init_user_ns, old_dir, whiteout,
 			    S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
 	dput(whiteout);
 	if (error)
@@ -3094,7 +3101,10 @@ static int shmem_whiteout(struct inode *old_dir, struct dentry *old_dentry)
  * it exists so that the VFS layer correctly free's it when it
  * gets overwritten.
  */
-static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags)
+static int shmem_rename2(struct user_namespace *mnt_userns,
+			 struct inode *old_dir, struct dentry *old_dentry,
+			 struct inode *new_dir, struct dentry *new_dentry,
+			 unsigned int flags)
 {
 	struct inode *inode = d_inode(old_dentry);
 	int they_are_dirs = S_ISDIR(inode->i_mode);
@@ -3111,7 +3121,7 @@ static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struc
 	if (flags & RENAME_WHITEOUT) {
 		int error;
 
-		error = shmem_whiteout(old_dir, old_dentry);
+		error = shmem_whiteout(&init_user_ns, old_dir, old_dentry);
 		if (error)
 			return error;
 	}
@@ -3135,7 +3145,8 @@ static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struc
 	return 0;
 }
 
-static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+static int shmem_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+			 struct dentry *dentry, const char *symname)
 {
 	int error;
 	int len;
@@ -3273,6 +3284,7 @@ static int shmem_xattr_handler_get(const struct xattr_handler *handler,
 }
 
 static int shmem_xattr_handler_set(const struct xattr_handler *handler,
+				   struct user_namespace *mnt_userns,
 				   struct dentry *unused, struct inode *inode,
 				   const char *name, const void *value,
 				   size_t size, int flags)
diff --git a/net/socket.c b/net/socket.c
index 7f0617ab5437..23c7842389de 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -334,6 +334,7 @@ static const struct xattr_handler sockfs_xattr_handler = {
 };
 
 static int sockfs_security_xattr_set(const struct xattr_handler *handler,
+				     struct user_namespace *mnt_userns,
 				     struct dentry *dentry, struct inode *inode,
 				     const char *suffix, const void *value,
 				     size_t size, int flags)
@@ -537,9 +538,10 @@ static ssize_t sockfs_listxattr(struct dentry *dentry, char *buffer,
 	return used;
 }
 
-static int sockfs_setattr(struct dentry *dentry, struct iattr *iattr)
+static int sockfs_setattr(struct user_namespace *mnt_userns,
+			  struct dentry *dentry, struct iattr *iattr)
 {
-	int err = simple_setattr(dentry, iattr);
+	int err = simple_setattr(&init_user_ns, dentry, iattr);
 
 	if (!err && (iattr->ia_valid & ATTR_UID)) {
 		struct socket *sock = SOCKET_I(d_inode(dentry));
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 41c3303c3357..5a31307ceb76 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -936,7 +936,7 @@ static struct sock *unix_find_other(struct net *net,
 		if (err)
 			goto fail;
 		inode = d_backing_inode(path.dentry);
-		err = inode_permission(inode, MAY_WRITE);
+		err = path_permission(&path, MAY_WRITE);
 		if (err)
 			goto put_fail;
 
@@ -996,7 +996,8 @@ static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
 	 */
 	err = security_path_mknod(&path, dentry, mode, 0);
 	if (!err) {
-		err = vfs_mknod(d_inode(path.dentry), dentry, mode, 0);
+		err = vfs_mknod(mnt_user_ns(path.mnt), d_inode(path.dentry),
+				dentry, mode, 0);
 		if (!err) {
 			res->mnt = mntget(path.mnt);
 			res->dentry = dget(dentry);
diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index f95c6bfa8b8e..2ee3b3d29f10 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -1773,7 +1773,8 @@ fail2:
 	return error;
 }
 
-static int ns_mkdir_op(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int ns_mkdir_op(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
 {
 	struct aa_ns *ns, *parent;
 	/* TODO: improve permission check */
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index f919ebd042fd..583680f6cd81 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -10,12 +10,14 @@
 
 #include <linux/errno.h>
 #include <linux/fdtable.h>
+#include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/mount.h>
 #include <linux/syscalls.h>
 #include <linux/tracehook.h>
 #include <linux/personality.h>
 #include <linux/xattr.h>
+#include <linux/user_namespace.h>
 
 #include "include/audit.h"
 #include "include/apparmorfs.h"
@@ -324,8 +326,8 @@ static int aa_xattrs_match(const struct linux_binprm *bprm,
 	d = bprm->file->f_path.dentry;
 
 	for (i = 0; i < profile->xattr_count; i++) {
-		size = vfs_getxattr_alloc(d, profile->xattrs[i], &value,
-					  value_size, GFP_KERNEL);
+		size = vfs_getxattr_alloc(&init_user_ns, d, profile->xattrs[i],
+					  &value, value_size, GFP_KERNEL);
 		if (size >= 0) {
 			u32 perm;
 
@@ -858,8 +860,10 @@ int apparmor_bprm_creds_for_exec(struct linux_binprm *bprm)
 	const char *info = NULL;
 	int error = 0;
 	bool unsafe = false;
+	kuid_t i_uid = i_uid_into_mnt(file_mnt_user_ns(bprm->file),
+				      file_inode(bprm->file));
 	struct path_cond cond = {
-		file_inode(bprm->file)->i_uid,
+		i_uid,
 		file_inode(bprm->file)->i_mode
 	};
 
@@ -967,8 +971,7 @@ audit:
 	error = fn_for_each(label, profile,
 			aa_audit_file(profile, &nullperms, OP_EXEC, MAY_EXEC,
 				      bprm->filename, NULL, new,
-				      file_inode(bprm->file)->i_uid, info,
-				      error));
+				      i_uid, info, error));
 	aa_put_label(new);
 	goto done;
 }
diff --git a/security/apparmor/file.c b/security/apparmor/file.c
index 92acf9a49405..e1b7e93602e4 100644
--- a/security/apparmor/file.c
+++ b/security/apparmor/file.c
@@ -11,6 +11,8 @@
 #include <linux/tty.h>
 #include <linux/fdtable.h>
 #include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
 
 #include "include/apparmor.h"
 #include "include/audit.h"
@@ -509,7 +511,7 @@ static int __file_path_perm(const char *op, struct aa_label *label,
 	struct aa_profile *profile;
 	struct aa_perms perms = {};
 	struct path_cond cond = {
-		.uid = file_inode(file)->i_uid,
+		.uid = i_uid_into_mnt(file_mnt_user_ns(file), file_inode(file)),
 		.mode = file_inode(file)->i_mode
 	};
 	char *buffer;
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 1b0aba8eb723..240a53387e6b 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -224,8 +224,10 @@ static int common_perm(const char *op, const struct path *path, u32 mask,
  */
 static int common_perm_cond(const char *op, const struct path *path, u32 mask)
 {
-	struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
-				  d_backing_inode(path->dentry)->i_mode
+	struct user_namespace *mnt_userns = mnt_user_ns(path->mnt);
+	struct path_cond cond = {
+		i_uid_into_mnt(mnt_userns, d_backing_inode(path->dentry)),
+		d_backing_inode(path->dentry)->i_mode
 	};
 
 	if (!path_mediated_fs(path->dentry))
@@ -266,12 +268,13 @@ static int common_perm_rm(const char *op, const struct path *dir,
 			  struct dentry *dentry, u32 mask)
 {
 	struct inode *inode = d_backing_inode(dentry);
+	struct user_namespace *mnt_userns = mnt_user_ns(dir->mnt);
 	struct path_cond cond = { };
 
 	if (!inode || !path_mediated_fs(dentry))
 		return 0;
 
-	cond.uid = inode->i_uid;
+	cond.uid = i_uid_into_mnt(mnt_userns, inode);
 	cond.mode = inode->i_mode;
 
 	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
@@ -361,12 +364,14 @@ static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_d
 
 	label = begin_current_label_crit_section();
 	if (!unconfined(label)) {
+		struct user_namespace *mnt_userns = mnt_user_ns(old_dir->mnt);
 		struct path old_path = { .mnt = old_dir->mnt,
 					 .dentry = old_dentry };
 		struct path new_path = { .mnt = new_dir->mnt,
 					 .dentry = new_dentry };
-		struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
-					  d_backing_inode(old_dentry)->i_mode
+		struct path_cond cond = {
+			i_uid_into_mnt(mnt_userns, d_backing_inode(old_dentry)),
+			d_backing_inode(old_dentry)->i_mode
 		};
 
 		error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
@@ -420,8 +425,12 @@ static int apparmor_file_open(struct file *file)
 
 	label = aa_get_newest_cred_label(file->f_cred);
 	if (!unconfined(label)) {
+		struct user_namespace *mnt_userns = file_mnt_user_ns(file);
 		struct inode *inode = file_inode(file);
-		struct path_cond cond = { inode->i_uid, inode->i_mode };
+		struct path_cond cond = {
+			i_uid_into_mnt(mnt_userns, inode),
+			inode->i_mode
+		};
 
 		error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
 				     aa_map_file_to_perms(file), &cond);
diff --git a/security/commoncap.c b/security/commoncap.c
index 78598be45f10..28f4d25480df 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -303,17 +303,25 @@ int cap_inode_need_killpriv(struct dentry *dentry)
 
 /**
  * cap_inode_killpriv - Erase the security markings on an inode
- * @dentry: The inode/dentry to alter
+ *
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dentry:	The inode/dentry to alter
  *
  * Erase the privilege-enhancing security markings on an inode.
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ *
  * Returns 0 if successful, -ve on error.
  */
-int cap_inode_killpriv(struct dentry *dentry)
+int cap_inode_killpriv(struct user_namespace *mnt_userns, struct dentry *dentry)
 {
 	int error;
 
-	error = __vfs_removexattr(dentry, XATTR_NAME_CAPS);
+	error = __vfs_removexattr(mnt_userns, dentry, XATTR_NAME_CAPS);
 	if (error == -EOPNOTSUPP)
 		error = 0;
 	return error;
@@ -366,7 +374,8 @@ static bool is_v3header(size_t size, const struct vfs_cap_data *cap)
  * by the integrity subsystem, which really wants the unconverted values -
  * so that's good.
  */
-int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
+int cap_inode_getsecurity(struct user_namespace *mnt_userns,
+			  struct inode *inode, const char *name, void **buffer,
 			  bool alloc)
 {
 	int size, ret;
@@ -387,8 +396,8 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
 		return -EINVAL;
 
 	size = sizeof(struct vfs_ns_cap_data);
-	ret = (int) vfs_getxattr_alloc(dentry, XATTR_NAME_CAPS,
-				 &tmpbuf, size, GFP_NOFS);
+	ret = (int)vfs_getxattr_alloc(mnt_userns, dentry, XATTR_NAME_CAPS,
+				      &tmpbuf, size, GFP_NOFS);
 	dput(dentry);
 
 	if (ret < 0)
@@ -408,6 +417,9 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
 
 	kroot = make_kuid(fs_ns, root);
 
+	/* If this is an idmapped mount shift the kuid. */
+	kroot = kuid_into_mnt(mnt_userns, kroot);
+
 	/* If the root kuid maps to a valid uid in current ns, then return
 	 * this as a nscap. */
 	mappedroot = from_kuid(current_user_ns(), kroot);
@@ -469,16 +481,33 @@ out_free:
 	return size;
 }
 
+/**
+ * rootid_from_xattr - translate root uid of vfs caps
+ *
+ * @value:	vfs caps value which may be modified by this function
+ * @size:	size of @ivalue
+ * @task_ns:	user namespace of the caller
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ */
 static kuid_t rootid_from_xattr(const void *value, size_t size,
-				struct user_namespace *task_ns)
+				struct user_namespace *task_ns,
+				struct user_namespace *mnt_userns)
 {
 	const struct vfs_ns_cap_data *nscap = value;
+	kuid_t rootkid;
 	uid_t rootid = 0;
 
 	if (size == XATTR_CAPS_SZ_3)
 		rootid = le32_to_cpu(nscap->rootid);
 
-	return make_kuid(task_ns, rootid);
+	rootkid = make_kuid(task_ns, rootid);
+	return kuid_from_mnt(mnt_userns, rootkid);
 }
 
 static bool validheader(size_t size, const struct vfs_cap_data *cap)
@@ -486,13 +515,27 @@ static bool validheader(size_t size, const struct vfs_cap_data *cap)
 	return is_v2header(size, cap) || is_v3header(size, cap);
 }
 
-/*
+/**
+ * cap_convert_nscap - check vfs caps
+ *
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dentry:	used to retrieve inode to check permissions on
+ * @ivalue:	vfs caps value which may be modified by this function
+ * @size:	size of @ivalue
+ *
  * User requested a write of security.capability.  If needed, update the
  * xattr to change from v2 to v3, or to fixup the v3 rootid.
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ *
  * If all is ok, we return the new size, on error return < 0.
  */
-int cap_convert_nscap(struct dentry *dentry, const void **ivalue, size_t size)
+int cap_convert_nscap(struct user_namespace *mnt_userns, struct dentry *dentry,
+		      const void **ivalue, size_t size)
 {
 	struct vfs_ns_cap_data *nscap;
 	uid_t nsrootid;
@@ -509,14 +552,14 @@ int cap_convert_nscap(struct dentry *dentry, const void **ivalue, size_t size)
 		return -EINVAL;
 	if (!validheader(size, cap))
 		return -EINVAL;
-	if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP))
+	if (!capable_wrt_inode_uidgid(mnt_userns, inode, CAP_SETFCAP))
 		return -EPERM;
-	if (size == XATTR_CAPS_SZ_2)
+	if (size == XATTR_CAPS_SZ_2 && (mnt_userns == &init_user_ns))
 		if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP))
 			/* user is privileged, just write the v2 */
 			return size;
 
-	rootid = rootid_from_xattr(*ivalue, size, task_ns);
+	rootid = rootid_from_xattr(*ivalue, size, task_ns, mnt_userns);
 	if (!uid_valid(rootid))
 		return -EINVAL;
 
@@ -593,10 +636,24 @@ static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps,
 	return *effective ? ret : 0;
 }
 
-/*
+/**
+ * get_vfs_caps_from_disk - retrieve vfs caps from disk
+ *
+ * @mnt_userns:	user namespace of the mount the inode was found from
+ * @dentry:	dentry from which @inode is retrieved
+ * @cpu_caps:	vfs capabilities
+ *
  * Extract the on-exec-apply capability sets for an executable file.
+ *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
  */
-int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps)
+int get_vfs_caps_from_disk(struct user_namespace *mnt_userns,
+			   const struct dentry *dentry,
+			   struct cpu_vfs_cap_data *cpu_caps)
 {
 	struct inode *inode = d_backing_inode(dentry);
 	__u32 magic_etc;
@@ -652,6 +709,7 @@ int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data
 	/* Limit the caps to the mounter of the filesystem
 	 * or the more limited uid specified in the xattr.
 	 */
+	rootkuid = kuid_into_mnt(mnt_userns, rootkuid);
 	if (!rootid_owns_currentns(rootkuid))
 		return -ENODATA;
 
@@ -697,7 +755,8 @@ static int get_file_caps(struct linux_binprm *bprm, struct file *file,
 	if (!current_in_userns(file->f_path.mnt->mnt_sb->s_user_ns))
 		return 0;
 
-	rc = get_vfs_caps_from_disk(file->f_path.dentry, &vcaps);
+	rc = get_vfs_caps_from_disk(file_mnt_user_ns(file),
+				    file->f_path.dentry, &vcaps);
 	if (rc < 0) {
 		if (rc == -EINVAL)
 			printk(KERN_NOTICE "Invalid argument reading file caps for %s\n",
@@ -962,16 +1021,25 @@ int cap_inode_setxattr(struct dentry *dentry, const char *name,
 
 /**
  * cap_inode_removexattr - Determine whether an xattr may be removed
- * @dentry: The inode/dentry being altered
- * @name: The name of the xattr to be changed
+ *
+ * @mnt_userns:	User namespace of the mount the inode was found from
+ * @dentry:	The inode/dentry being altered
+ * @name:	The name of the xattr to be changed
  *
  * Determine whether an xattr may be removed from an inode, returning 0 if
  * permission is granted, -ve if denied.
  *
+ * If the inode has been found through an idmapped mount the user namespace of
+ * the vfsmount must be passed through @mnt_userns. This function will then
+ * take care to map the inode according to @mnt_userns before checking
+ * permissions. On non-idmapped mounts or if permission checking is to be
+ * performed on the raw inode simply passs init_user_ns.
+ *
  * This is used to make sure security xattrs don't get removed by those who
  * aren't privileged to remove them.
  */
-int cap_inode_removexattr(struct dentry *dentry, const char *name)
+int cap_inode_removexattr(struct user_namespace *mnt_userns,
+			  struct dentry *dentry, const char *name)
 {
 	struct user_namespace *user_ns = dentry->d_sb->s_user_ns;
 
@@ -985,7 +1053,7 @@ int cap_inode_removexattr(struct dentry *dentry, const char *name)
 		struct inode *inode = d_backing_inode(dentry);
 		if (!inode)
 			return -EINVAL;
-		if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP))
+		if (!capable_wrt_inode_uidgid(mnt_userns, inode, CAP_SETFCAP))
 			return -EPERM;
 		return 0;
 	}
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index a6dd47eb086d..d76b006cbcc4 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -225,7 +225,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
 				ima_present = true;
 			continue;
 		}
-		size = vfs_getxattr_alloc(dentry, xattr->name,
+		size = vfs_getxattr_alloc(&init_user_ns, dentry, xattr->name,
 					  &xattr_value, xattr_size, GFP_NOFS);
 		if (size == -ENOMEM) {
 			error = -ENOMEM;
@@ -278,8 +278,8 @@ static int evm_is_immutable(struct dentry *dentry, struct inode *inode)
 		return 1;
 
 	/* Do this the hard way */
-	rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0,
-				GFP_NOFS);
+	rc = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_EVM,
+				(char **)&xattr_data, 0, GFP_NOFS);
 	if (rc <= 0) {
 		if (rc == -ENODATA)
 			return 0;
@@ -322,11 +322,12 @@ int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name,
 			   xattr_value_len, &data);
 	if (rc == 0) {
 		data.hdr.xattr.sha1.type = EVM_XATTR_HMAC;
-		rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_EVM,
+		rc = __vfs_setxattr_noperm(&init_user_ns, dentry,
+					   XATTR_NAME_EVM,
 					   &data.hdr.xattr.data[1],
 					   SHA1_DIGEST_SIZE + 1, 0);
 	} else if (rc == -ENODATA && (inode->i_opflags & IOP_XATTR)) {
-		rc = __vfs_removexattr(dentry, XATTR_NAME_EVM);
+		rc = __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_EVM);
 	}
 	return rc;
 }
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 76d19146d74b..0de367aaa2d3 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -146,8 +146,8 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry,
 	/* if status is not PASS, try to check again - against -ENOMEM */
 
 	/* first need to know the sig type */
-	rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0,
-				GFP_NOFS);
+	rc = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_EVM,
+				(char **)&xattr_data, 0, GFP_NOFS);
 	if (rc <= 0) {
 		evm_status = INTEGRITY_FAIL;
 		if (rc == -ENODATA) {
diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c
index cfc3075769bb..bbc85637e18b 100644
--- a/security/integrity/evm/evm_secfs.c
+++ b/security/integrity/evm/evm_secfs.c
@@ -219,7 +219,7 @@ static ssize_t evm_write_xattrs(struct file *file, const char __user *buf,
 		newattrs.ia_valid = ATTR_MODE;
 		inode = evm_xattrs->d_inode;
 		inode_lock(inode);
-		err = simple_setattr(evm_xattrs, &newattrs);
+		err = simple_setattr(&init_user_ns, evm_xattrs, &newattrs);
 		inode_unlock(inode);
 		if (!err)
 			err = count;
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index aa312472c7c5..8e8b5251550e 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -254,8 +254,9 @@ static inline void ima_process_queued_keys(void) {}
 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */
 
 /* LIM API function definitions */
-int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
-		   int mask, enum ima_hooks func, int *pcr,
+int ima_get_action(struct user_namespace *mnt_userns, struct inode *inode,
+		   const struct cred *cred, u32 secid, int mask,
+		   enum ima_hooks func, int *pcr,
 		   struct ima_template_desc **template_desc,
 		   const char *func_data);
 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
@@ -267,7 +268,8 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
 			   struct evm_ima_xattr_data *xattr_value,
 			   int xattr_len, const struct modsig *modsig, int pcr,
 			   struct ima_template_desc *template_desc);
-void process_buffer_measurement(struct inode *inode, const void *buf, int size,
+void process_buffer_measurement(struct user_namespace *mnt_userns,
+				struct inode *inode, const void *buf, int size,
 				const char *eventname, enum ima_hooks func,
 				int pcr, const char *func_data,
 				bool buf_hash);
@@ -283,8 +285,9 @@ void ima_free_template_entry(struct ima_template_entry *entry);
 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
 
 /* IMA policy related functions */
-int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
-		     enum ima_hooks func, int mask, int flags, int *pcr,
+int ima_match_policy(struct user_namespace *mnt_userns, struct inode *inode,
+		     const struct cred *cred, u32 secid, enum ima_hooks func,
+		     int mask, int flags, int *pcr,
 		     struct ima_template_desc **template_desc,
 		     const char *func_data);
 void ima_init_policy(void);
@@ -315,7 +318,8 @@ int ima_appraise_measurement(enum ima_hooks func,
 			     struct file *file, const unsigned char *filename,
 			     struct evm_ima_xattr_data *xattr_value,
 			     int xattr_len, const struct modsig *modsig);
-int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func);
+int ima_must_appraise(struct user_namespace *mnt_userns, struct inode *inode,
+		      int mask, enum ima_hooks func);
 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
 					   enum ima_hooks func);
@@ -342,7 +346,8 @@ static inline int ima_appraise_measurement(enum ima_hooks func,
 	return INTEGRITY_UNKNOWN;
 }
 
-static inline int ima_must_appraise(struct inode *inode, int mask,
+static inline int ima_must_appraise(struct user_namespace *mnt_userns,
+				    struct inode *inode, int mask,
 				    enum ima_hooks func)
 {
 	return 0;
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 1dd70dc68ffd..d8e321cc6936 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -162,6 +162,7 @@ err_out:
 
 /**
  * ima_get_action - appraise & measure decision based on policy.
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode: pointer to the inode associated with the object being validated
  * @cred: pointer to credentials structure to validate
  * @secid: secid of the task being validated
@@ -183,8 +184,9 @@ err_out:
  * Returns IMA_MEASURE, IMA_APPRAISE mask.
  *
  */
-int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
-		   int mask, enum ima_hooks func, int *pcr,
+int ima_get_action(struct user_namespace *mnt_userns, struct inode *inode,
+		   const struct cred *cred, u32 secid, int mask,
+		   enum ima_hooks func, int *pcr,
 		   struct ima_template_desc **template_desc,
 		   const char *func_data)
 {
@@ -192,8 +194,8 @@ int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
 
 	flags &= ima_policy_flag;
 
-	return ima_match_policy(inode, cred, secid, func, mask, flags, pcr,
-				template_desc, func_data);
+	return ima_match_policy(mnt_userns, inode, cred, secid, func, mask,
+				flags, pcr, template_desc, func_data);
 }
 
 /*
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 46ffa38bab12..565e33ff19d0 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -68,7 +68,8 @@ bool is_ima_appraise_enabled(void)
  *
  * Return 1 to appraise or hash
  */
-int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
+int ima_must_appraise(struct user_namespace *mnt_userns, struct inode *inode,
+		      int mask, enum ima_hooks func)
 {
 	u32 secid;
 
@@ -76,8 +77,8 @@ int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
 		return 0;
 
 	security_task_getsecid(current, &secid);
-	return ima_match_policy(inode, current_cred(), secid, func, mask,
-				IMA_APPRAISE | IMA_HASH, NULL, NULL, NULL);
+	return ima_match_policy(mnt_userns, inode, current_cred(), secid, func,
+				mask, IMA_APPRAISE | IMA_HASH, NULL, NULL, NULL);
 }
 
 static int ima_fix_xattr(struct dentry *dentry,
@@ -94,7 +95,7 @@ static int ima_fix_xattr(struct dentry *dentry,
 		iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG;
 		iint->ima_hash->xattr.ng.algo = algo;
 	}
-	rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA,
+	rc = __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_IMA,
 				   &iint->ima_hash->xattr.data[offset],
 				   (sizeof(iint->ima_hash->xattr) - offset) +
 				   iint->ima_hash->length, 0);
@@ -215,8 +216,8 @@ int ima_read_xattr(struct dentry *dentry,
 {
 	ssize_t ret;
 
-	ret = vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)xattr_value,
-				 0, GFP_NOFS);
+	ret = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_IMA,
+				 (char **)xattr_value, 0, GFP_NOFS);
 	if (ret == -EOPNOTSUPP)
 		ret = 0;
 	return ret;
@@ -350,7 +351,7 @@ int ima_check_blacklist(struct integrity_iint_cache *iint,
 
 		rc = is_binary_blacklisted(digest, digestsize);
 		if ((rc == -EPERM) && (iint->flags & IMA_MEASURE))
-			process_buffer_measurement(NULL, digest, digestsize,
+			process_buffer_measurement(&init_user_ns, NULL, digest, digestsize,
 						   "blacklisted-hash", NONE,
 						   pcr, NULL, false);
 	}
@@ -501,6 +502,7 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
 
 /**
  * ima_inode_post_setattr - reflect file metadata changes
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @dentry: pointer to the affected dentry
  *
  * Changes to a dentry's metadata might result in needing to appraise.
@@ -508,7 +510,8 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
  * This function is called from notify_change(), which expects the caller
  * to lock the inode's i_mutex.
  */
-void ima_inode_post_setattr(struct dentry *dentry)
+void ima_inode_post_setattr(struct user_namespace *mnt_userns,
+			    struct dentry *dentry)
 {
 	struct inode *inode = d_backing_inode(dentry);
 	struct integrity_iint_cache *iint;
@@ -518,9 +521,9 @@ void ima_inode_post_setattr(struct dentry *dentry)
 	    || !(inode->i_opflags & IOP_XATTR))
 		return;
 
-	action = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR);
+	action = ima_must_appraise(mnt_userns, inode, MAY_ACCESS, POST_SETATTR);
 	if (!action)
-		__vfs_removexattr(dentry, XATTR_NAME_IMA);
+		__vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_IMA);
 	iint = integrity_iint_find(inode);
 	if (iint) {
 		set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags);
diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c
index a74095793936..1fb0b0e09559 100644
--- a/security/integrity/ima/ima_asymmetric_keys.c
+++ b/security/integrity/ima/ima_asymmetric_keys.c
@@ -10,6 +10,7 @@
  */
 
 #include <keys/asymmetric-type.h>
+#include <linux/user_namespace.h>
 #include "ima.h"
 
 /**
@@ -58,7 +59,7 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key,
 	 * if the IMA policy is configured to measure a key linked
 	 * to the given keyring.
 	 */
-	process_buffer_measurement(NULL, payload, payload_len,
+	process_buffer_measurement(&init_user_ns, NULL, payload, payload_len,
 				   keyring->description, KEY_CHECK, 0,
 				   keyring->description, false);
 }
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 6a429846f90a..9ef748ea829f 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -218,8 +218,8 @@ static int process_measurement(struct file *file, const struct cred *cred,
 	 * bitmask based on the appraise/audit/measurement policy.
 	 * Included is the appraise submask.
 	 */
-	action = ima_get_action(inode, cred, secid, mask, func, &pcr,
-				&template_desc, NULL);
+	action = ima_get_action(file_mnt_user_ns(file), inode, cred, secid,
+				mask, func, &pcr, &template_desc, NULL);
 	violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
 			   (ima_policy_flag & IMA_MEASURE));
 	if (!action && !violation_check)
@@ -431,8 +431,9 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
 
 	security_task_getsecid(current, &secid);
 	inode = file_inode(vma->vm_file);
-	action = ima_get_action(inode, current_cred(), secid, MAY_EXEC,
-				MMAP_CHECK, &pcr, &template, 0);
+	action = ima_get_action(file_mnt_user_ns(vma->vm_file), inode,
+				current_cred(), secid, MAY_EXEC, MMAP_CHECK,
+				&pcr, &template, 0);
 
 	/* Is the mmap'ed file in policy? */
 	if (!(action & (IMA_MEASURE | IMA_APPRAISE_SUBMASK)))
@@ -592,18 +593,21 @@ EXPORT_SYMBOL_GPL(ima_inode_hash);
 
 /**
  * ima_post_create_tmpfile - mark newly created tmpfile as new
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @file : newly created tmpfile
  *
  * No measuring, appraising or auditing of newly created tmpfiles is needed.
  * Skip calling process_measurement(), but indicate which newly, created
  * tmpfiles are in policy.
  */
-void ima_post_create_tmpfile(struct inode *inode)
+void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
+			     struct inode *inode)
 {
 	struct integrity_iint_cache *iint;
 	int must_appraise;
 
-	must_appraise = ima_must_appraise(inode, MAY_ACCESS, FILE_CHECK);
+	must_appraise = ima_must_appraise(mnt_userns, inode, MAY_ACCESS,
+					  FILE_CHECK);
 	if (!must_appraise)
 		return;
 
@@ -619,18 +623,21 @@ void ima_post_create_tmpfile(struct inode *inode)
 
 /**
  * ima_post_path_mknod - mark as a new inode
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @dentry: newly created dentry
  *
  * Mark files created via the mknodat syscall as new, so that the
  * file data can be written later.
  */
-void ima_post_path_mknod(struct dentry *dentry)
+void ima_post_path_mknod(struct user_namespace *mnt_userns,
+			 struct dentry *dentry)
 {
 	struct integrity_iint_cache *iint;
 	struct inode *inode = dentry->d_inode;
 	int must_appraise;
 
-	must_appraise = ima_must_appraise(inode, MAY_ACCESS, FILE_CHECK);
+	must_appraise = ima_must_appraise(mnt_userns, inode, MAY_ACCESS,
+					  FILE_CHECK);
 	if (!must_appraise)
 		return;
 
@@ -810,6 +817,7 @@ int ima_post_load_data(char *buf, loff_t size,
 
 /*
  * process_buffer_measurement - Measure the buffer or the buffer data hash
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode: inode associated with the object being measured (NULL for KEY_CHECK)
  * @buf: pointer to the buffer that needs to be added to the log.
  * @size: size of buffer(in bytes).
@@ -821,7 +829,8 @@ int ima_post_load_data(char *buf, loff_t size,
  *
  * Based on policy, either the buffer data or buffer data hash is measured
  */
-void process_buffer_measurement(struct inode *inode, const void *buf, int size,
+void process_buffer_measurement(struct user_namespace *mnt_userns,
+				struct inode *inode, const void *buf, int size,
 				const char *eventname, enum ima_hooks func,
 				int pcr, const char *func_data,
 				bool buf_hash)
@@ -864,8 +873,9 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
 	 */
 	if (func) {
 		security_task_getsecid(current, &secid);
-		action = ima_get_action(inode, current_cred(), secid, 0, func,
-					&pcr, &template, func_data);
+		action = ima_get_action(mnt_userns, inode, current_cred(),
+					secid, 0, func, &pcr, &template,
+					func_data);
 		if (!(action & IMA_MEASURE))
 			return;
 	}
@@ -937,9 +947,9 @@ void ima_kexec_cmdline(int kernel_fd, const void *buf, int size)
 	if (!f.file)
 		return;
 
-	process_buffer_measurement(file_inode(f.file), buf, size,
-				   "kexec-cmdline", KEXEC_CMDLINE, 0, NULL,
-				   false);
+	process_buffer_measurement(file_mnt_user_ns(f.file), file_inode(f.file),
+				   buf, size, "kexec-cmdline", KEXEC_CMDLINE, 0,
+				   NULL, false);
 	fdput(f);
 }
 
@@ -964,7 +974,7 @@ void ima_measure_critical_data(const char *event_label,
 	if (!event_name || !event_label || !buf || !buf_len)
 		return;
 
-	process_buffer_measurement(NULL, buf, buf_len, event_name,
+	process_buffer_measurement(&init_user_ns, NULL, buf, buf_len, event_name,
 				   CRITICAL_DATA, 0, event_label,
 				   hash);
 }
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 9b45d064a87d..4f8cb155e4fd 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -513,6 +513,7 @@ static bool ima_match_rule_data(struct ima_rule_entry *rule,
 /**
  * ima_match_rules - determine whether an inode matches the policy rule.
  * @rule: a pointer to a rule
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode: a pointer to an inode
  * @cred: a pointer to a credentials structure for user validation
  * @secid: the secid of the task to be validated
@@ -522,9 +523,10 @@ static bool ima_match_rule_data(struct ima_rule_entry *rule,
  *
  * Returns true on rule match, false on failure.
  */
-static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
-			    const struct cred *cred, u32 secid,
-			    enum ima_hooks func, int mask,
+static bool ima_match_rules(struct ima_rule_entry *rule,
+			    struct user_namespace *mnt_userns,
+			    struct inode *inode, const struct cred *cred,
+			    u32 secid, enum ima_hooks func, int mask,
 			    const char *func_data)
 {
 	int i;
@@ -570,7 +572,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
 	}
 
 	if ((rule->flags & IMA_FOWNER) &&
-	    !rule->fowner_op(inode->i_uid, rule->fowner))
+	    !rule->fowner_op(i_uid_into_mnt(mnt_userns, inode), rule->fowner))
 		return false;
 	for (i = 0; i < MAX_LSM_RULES; i++) {
 		int rc = 0;
@@ -633,6 +635,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
 
 /**
  * ima_match_policy - decision based on LSM and other conditions
+ * @mnt_userns:	user namespace of the mount the inode was found from
  * @inode: pointer to an inode for which the policy decision is being made
  * @cred: pointer to a credentials structure for which the policy decision is
  *        being made
@@ -650,8 +653,9 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
  * list when walking it.  Reads are many orders of magnitude more numerous
  * than writes so ima_match_policy() is classical RCU candidate.
  */
-int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
-		     enum ima_hooks func, int mask, int flags, int *pcr,
+int ima_match_policy(struct user_namespace *mnt_userns, struct inode *inode,
+		     const struct cred *cred, u32 secid, enum ima_hooks func,
+		     int mask, int flags, int *pcr,
 		     struct ima_template_desc **template_desc,
 		     const char *func_data)
 {
@@ -667,8 +671,8 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
 		if (!(entry->action & actmask))
 			continue;
 
-		if (!ima_match_rules(entry, inode, cred, secid, func, mask,
-				     func_data))
+		if (!ima_match_rules(entry, mnt_userns, inode, cred, secid,
+				     func, mask, func_data))
 			continue;
 
 		action |= entry->flags & IMA_ACTION_FLAGS;
diff --git a/security/integrity/ima/ima_queue_keys.c b/security/integrity/ima/ima_queue_keys.c
index c2f2ad34f9b7..979ef6c71f3d 100644
--- a/security/integrity/ima/ima_queue_keys.c
+++ b/security/integrity/ima/ima_queue_keys.c
@@ -8,6 +8,7 @@
  *       Enables deferred processing of keys
  */
 
+#include <linux/user_namespace.h>
 #include <linux/workqueue.h>
 #include <keys/asymmetric-type.h>
 #include "ima.h"
@@ -158,7 +159,8 @@ void ima_process_queued_keys(void)
 
 	list_for_each_entry_safe(entry, tmp, &ima_keys, list) {
 		if (!timer_expired)
-			process_buffer_measurement(NULL, entry->payload,
+			process_buffer_measurement(&init_user_ns, NULL,
+						   entry->payload,
 						   entry->payload_len,
 						   entry->keyring_name,
 						   KEY_CHECK, 0,
diff --git a/security/security.c b/security/security.c
index 401663b5b70e..5ac96b16f8fa 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1288,7 +1288,8 @@ int security_inode_getattr(const struct path *path)
 	return call_int_hook(inode_getattr, 0, path);
 }
 
-int security_inode_setxattr(struct dentry *dentry, const char *name,
+int security_inode_setxattr(struct user_namespace *mnt_userns,
+			    struct dentry *dentry, const char *name,
 			    const void *value, size_t size, int flags)
 {
 	int ret;
@@ -1299,8 +1300,8 @@ int security_inode_setxattr(struct dentry *dentry, const char *name,
 	 * SELinux and Smack integrate the cap call,
 	 * so assume that all LSMs supplying this call do so.
 	 */
-	ret = call_int_hook(inode_setxattr, 1, dentry, name, value, size,
-				flags);
+	ret = call_int_hook(inode_setxattr, 1, mnt_userns, dentry, name, value,
+			    size, flags);
 
 	if (ret == 1)
 		ret = cap_inode_setxattr(dentry, name, value, size, flags);
@@ -1335,7 +1336,8 @@ int security_inode_listxattr(struct dentry *dentry)
 	return call_int_hook(inode_listxattr, 0, dentry);
 }
 
-int security_inode_removexattr(struct dentry *dentry, const char *name)
+int security_inode_removexattr(struct user_namespace *mnt_userns,
+			       struct dentry *dentry, const char *name)
 {
 	int ret;
 
@@ -1345,9 +1347,9 @@ int security_inode_removexattr(struct dentry *dentry, const char *name)
 	 * SELinux and Smack integrate the cap call,
 	 * so assume that all LSMs supplying this call do so.
 	 */
-	ret = call_int_hook(inode_removexattr, 1, dentry, name);
+	ret = call_int_hook(inode_removexattr, 1, mnt_userns, dentry, name);
 	if (ret == 1)
-		ret = cap_inode_removexattr(dentry, name);
+		ret = cap_inode_removexattr(mnt_userns, dentry, name);
 	if (ret)
 		return ret;
 	ret = ima_inode_removexattr(dentry, name);
@@ -1361,12 +1363,15 @@ int security_inode_need_killpriv(struct dentry *dentry)
 	return call_int_hook(inode_need_killpriv, 0, dentry);
 }
 
-int security_inode_killpriv(struct dentry *dentry)
+int security_inode_killpriv(struct user_namespace *mnt_userns,
+			    struct dentry *dentry)
 {
-	return call_int_hook(inode_killpriv, 0, dentry);
+	return call_int_hook(inode_killpriv, 0, mnt_userns, dentry);
 }
 
-int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
+int security_inode_getsecurity(struct user_namespace *mnt_userns,
+			       struct inode *inode, const char *name,
+			       void **buffer, bool alloc)
 {
 	struct security_hook_list *hp;
 	int rc;
@@ -1377,7 +1382,7 @@ int security_inode_getsecurity(struct inode *inode, const char *name, void **buf
 	 * Only one module will provide an attribute with a given name.
 	 */
 	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecurity, list) {
-		rc = hp->hook.inode_getsecurity(inode, name, buffer, alloc);
+		rc = hp->hook.inode_getsecurity(mnt_userns, inode, name, buffer, alloc);
 		if (rc != LSM_RET_DEFAULT(inode_getsecurity))
 			return rc;
 	}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index af2994adf9dd..ddd097790d47 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3203,7 +3203,8 @@ static bool has_cap_mac_admin(bool audit)
 	return true;
 }
 
-static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
+static int selinux_inode_setxattr(struct user_namespace *mnt_userns,
+				  struct dentry *dentry, const char *name,
 				  const void *value, size_t size, int flags)
 {
 	struct inode *inode = d_backing_inode(dentry);
@@ -3224,13 +3225,13 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
 	}
 
 	if (!selinux_initialized(&selinux_state))
-		return (inode_owner_or_capable(inode) ? 0 : -EPERM);
+		return (inode_owner_or_capable(mnt_userns, inode) ? 0 : -EPERM);
 
 	sbsec = inode->i_sb->s_security;
 	if (!(sbsec->flags & SBLABEL_MNT))
 		return -EOPNOTSUPP;
 
-	if (!inode_owner_or_capable(inode))
+	if (!inode_owner_or_capable(mnt_userns, inode))
 		return -EPERM;
 
 	ad.type = LSM_AUDIT_DATA_DENTRY;
@@ -3351,10 +3352,11 @@ static int selinux_inode_listxattr(struct dentry *dentry)
 	return dentry_has_perm(cred, dentry, FILE__GETATTR);
 }
 
-static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
+static int selinux_inode_removexattr(struct user_namespace *mnt_userns,
+				     struct dentry *dentry, const char *name)
 {
 	if (strcmp(name, XATTR_NAME_SELINUX)) {
-		int rc = cap_inode_removexattr(dentry, name);
+		int rc = cap_inode_removexattr(mnt_userns, dentry, name);
 		if (rc)
 			return rc;
 
@@ -3420,7 +3422,9 @@ static int selinux_path_notify(const struct path *path, u64 mask,
  *
  * Permission check is handled by selinux_inode_getxattr hook.
  */
-static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
+static int selinux_inode_getsecurity(struct user_namespace *mnt_userns,
+				     struct inode *inode, const char *name,
+				     void **buffer, bool alloc)
 {
 	u32 size;
 	int error;
@@ -6614,14 +6618,15 @@ static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen
  */
 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
 {
-	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
+	return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SELINUX,
+				     ctx, ctxlen, 0);
 }
 
 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
 {
 	int len = 0;
-	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
-						ctx, true);
+	len = selinux_inode_getsecurity(&init_user_ns, inode,
+					XATTR_SELINUX_SUFFIX, ctx, true);
 	if (len < 0)
 		return len;
 	*ctxlen = len;
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index f69c3dd9a0c6..12a45e61c1a5 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1240,7 +1240,8 @@ static int smack_inode_getattr(const struct path *path)
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_setxattr(struct dentry *dentry, const char *name,
+static int smack_inode_setxattr(struct user_namespace *mnt_userns,
+				struct dentry *dentry, const char *name,
 				const void *value, size_t size, int flags)
 {
 	struct smk_audit_info ad;
@@ -1362,7 +1363,8 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name)
  *
  * Returns 0 if access is permitted, an error code otherwise
  */
-static int smack_inode_removexattr(struct dentry *dentry, const char *name)
+static int smack_inode_removexattr(struct user_namespace *mnt_userns,
+				   struct dentry *dentry, const char *name)
 {
 	struct inode_smack *isp;
 	struct smk_audit_info ad;
@@ -1377,7 +1379,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
 		if (!smack_privileged(CAP_MAC_ADMIN))
 			rc = -EPERM;
 	} else
-		rc = cap_inode_removexattr(dentry, name);
+		rc = cap_inode_removexattr(mnt_userns, dentry, name);
 
 	if (rc != 0)
 		return rc;
@@ -1420,9 +1422,9 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
  *
  * Returns the size of the attribute or an error code
  */
-static int smack_inode_getsecurity(struct inode *inode,
-				   const char *name, void **buffer,
-				   bool alloc)
+static int smack_inode_getsecurity(struct user_namespace *mnt_userns,
+				   struct inode *inode, const char *name,
+				   void **buffer, bool alloc)
 {
 	struct socket_smack *ssp;
 	struct socket *sock;
@@ -3425,7 +3427,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
 			 */
 			if (isp->smk_flags & SMK_INODE_CHANGED) {
 				isp->smk_flags &= ~SMK_INODE_CHANGED;
-				rc = __vfs_setxattr(dp, inode,
+				rc = __vfs_setxattr(&init_user_ns, dp, inode,
 					XATTR_NAME_SMACKTRANSMUTE,
 					TRANS_TRUE, TRANS_TRUE_SIZE,
 					0);
@@ -4597,12 +4599,14 @@ static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
 
 static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
 {
-	return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
+	return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx,
+				       ctxlen, 0);
 }
 
 static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
 {
-	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
+	return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SMACK,
+				     ctx, ctxlen, 0);
 }
 
 static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
diff --git a/tools/include/uapi/asm-generic/unistd.h b/tools/include/uapi/asm-generic/unistd.h
index 728752917785..ce58cff99b66 100644
--- a/tools/include/uapi/asm-generic/unistd.h
+++ b/tools/include/uapi/asm-generic/unistd.h
@@ -861,9 +861,11 @@ __SYSCALL(__NR_faccessat2, sys_faccessat2)
 __SYSCALL(__NR_process_madvise, sys_process_madvise)
 #define __NR_epoll_pwait2 441
 __SC_COMP(__NR_epoll_pwait2, sys_epoll_pwait2, compat_sys_epoll_pwait2)
+#define __NR_mount_setattr 442
+__SYSCALL(__NR_mount_setattr, sys_mount_setattr)
 
 #undef __NR_syscalls
-#define __NR_syscalls 442
+#define __NR_syscalls 443
 
 /*
  * 32 bit systems traditionally used different
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 41f0a0adbb80..6c575cf34a71 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -33,6 +33,7 @@ TARGETS += memfd
 TARGETS += memory-hotplug
 TARGETS += mincore
 TARGETS += mount
+TARGETS += mount_setattr
 TARGETS += mqueue
 TARGETS += nci
 TARGETS += net
diff --git a/tools/testing/selftests/mount_setattr/.gitignore b/tools/testing/selftests/mount_setattr/.gitignore
new file mode 100644
index 000000000000..5f74d8488472
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/.gitignore
@@ -0,0 +1 @@
+mount_setattr_test
diff --git a/tools/testing/selftests/mount_setattr/Makefile b/tools/testing/selftests/mount_setattr/Makefile
new file mode 100644
index 000000000000..2250f7dcb81e
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for mount selftests.
+CFLAGS = -g -I../../../../usr/include/ -Wall -O2 -pthread
+
+TEST_GEN_FILES += mount_setattr_test
+
+include ../lib.mk
diff --git a/tools/testing/selftests/mount_setattr/config b/tools/testing/selftests/mount_setattr/config
new file mode 100644
index 000000000000..416bd53ce982
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/config
@@ -0,0 +1 @@
+CONFIG_USER_NS=y
diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
new file mode 100644
index 000000000000..4e94e566e040
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
@@ -0,0 +1,1424 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+#include <stdio.h>
+#include <errno.h>
+#include <pthread.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <sys/wait.h>
+#include <sys/vfs.h>
+#include <sys/statvfs.h>
+#include <sys/sysinfo.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <grp.h>
+#include <stdbool.h>
+#include <stdarg.h>
+
+#include "../kselftest_harness.h"
+
+#ifndef CLONE_NEWNS
+#define CLONE_NEWNS 0x00020000
+#endif
+
+#ifndef CLONE_NEWUSER
+#define CLONE_NEWUSER 0x10000000
+#endif
+
+#ifndef MS_REC
+#define MS_REC 16384
+#endif
+
+#ifndef MS_RELATIME
+#define MS_RELATIME (1 << 21)
+#endif
+
+#ifndef MS_STRICTATIME
+#define MS_STRICTATIME (1 << 24)
+#endif
+
+#ifndef MOUNT_ATTR_RDONLY
+#define MOUNT_ATTR_RDONLY 0x00000001
+#endif
+
+#ifndef MOUNT_ATTR_NOSUID
+#define MOUNT_ATTR_NOSUID 0x00000002
+#endif
+
+#ifndef MOUNT_ATTR_NOEXEC
+#define MOUNT_ATTR_NOEXEC 0x00000008
+#endif
+
+#ifndef MOUNT_ATTR_NODIRATIME
+#define MOUNT_ATTR_NODIRATIME 0x00000080
+#endif
+
+#ifndef MOUNT_ATTR__ATIME
+#define MOUNT_ATTR__ATIME 0x00000070
+#endif
+
+#ifndef MOUNT_ATTR_RELATIME
+#define MOUNT_ATTR_RELATIME 0x00000000
+#endif
+
+#ifndef MOUNT_ATTR_NOATIME
+#define MOUNT_ATTR_NOATIME 0x00000010
+#endif
+
+#ifndef MOUNT_ATTR_STRICTATIME
+#define MOUNT_ATTR_STRICTATIME 0x00000020
+#endif
+
+#ifndef AT_RECURSIVE
+#define AT_RECURSIVE 0x8000
+#endif
+
+#ifndef MS_SHARED
+#define MS_SHARED (1 << 20)
+#endif
+
+#define DEFAULT_THREADS 4
+#define ptr_to_int(p) ((int)((intptr_t)(p)))
+#define int_to_ptr(u) ((void *)((intptr_t)(u)))
+
+#ifndef __NR_mount_setattr
+	#if defined __alpha__
+		#define __NR_mount_setattr 552
+	#elif defined _MIPS_SIM
+		#if _MIPS_SIM == _MIPS_SIM_ABI32	/* o32 */
+			#define __NR_mount_setattr (442 + 4000)
+		#endif
+		#if _MIPS_SIM == _MIPS_SIM_NABI32	/* n32 */
+			#define __NR_mount_setattr (442 + 6000)
+		#endif
+		#if _MIPS_SIM == _MIPS_SIM_ABI64	/* n64 */
+			#define __NR_mount_setattr (442 + 5000)
+		#endif
+	#elif defined __ia64__
+		#define __NR_mount_setattr (442 + 1024)
+	#else
+		#define __NR_mount_setattr 442
+	#endif
+
+struct mount_attr {
+	__u64 attr_set;
+	__u64 attr_clr;
+	__u64 propagation;
+	__u64 userns_fd;
+};
+#endif
+
+#ifndef __NR_open_tree
+	#if defined __alpha__
+		#define __NR_open_tree 538
+	#elif defined _MIPS_SIM
+		#if _MIPS_SIM == _MIPS_SIM_ABI32	/* o32 */
+			#define __NR_open_tree 4428
+		#endif
+		#if _MIPS_SIM == _MIPS_SIM_NABI32	/* n32 */
+			#define __NR_open_tree 6428
+		#endif
+		#if _MIPS_SIM == _MIPS_SIM_ABI64	/* n64 */
+			#define __NR_open_tree 5428
+		#endif
+	#elif defined __ia64__
+		#define __NR_open_tree (428 + 1024)
+	#else
+		#define __NR_open_tree 428
+	#endif
+#endif
+
+#ifndef MOUNT_ATTR_IDMAP
+#define MOUNT_ATTR_IDMAP 0x00100000
+#endif
+
+static inline int sys_mount_setattr(int dfd, const char *path, unsigned int flags,
+				    struct mount_attr *attr, size_t size)
+{
+	return syscall(__NR_mount_setattr, dfd, path, flags, attr, size);
+}
+
+#ifndef OPEN_TREE_CLONE
+#define OPEN_TREE_CLONE 1
+#endif
+
+#ifndef OPEN_TREE_CLOEXEC
+#define OPEN_TREE_CLOEXEC O_CLOEXEC
+#endif
+
+#ifndef AT_RECURSIVE
+#define AT_RECURSIVE 0x8000 /* Apply to the entire subtree */
+#endif
+
+static inline int sys_open_tree(int dfd, const char *filename, unsigned int flags)
+{
+	return syscall(__NR_open_tree, dfd, filename, flags);
+}
+
+static ssize_t write_nointr(int fd, const void *buf, size_t count)
+{
+	ssize_t ret;
+
+	do {
+		ret = write(fd, buf, count);
+	} while (ret < 0 && errno == EINTR);
+
+	return ret;
+}
+
+static int write_file(const char *path, const void *buf, size_t count)
+{
+	int fd;
+	ssize_t ret;
+
+	fd = open(path, O_WRONLY | O_CLOEXEC | O_NOCTTY | O_NOFOLLOW);
+	if (fd < 0)
+		return -1;
+
+	ret = write_nointr(fd, buf, count);
+	close(fd);
+	if (ret < 0 || (size_t)ret != count)
+		return -1;
+
+	return 0;
+}
+
+static int create_and_enter_userns(void)
+{
+	uid_t uid;
+	gid_t gid;
+	char map[100];
+
+	uid = getuid();
+	gid = getgid();
+
+	if (unshare(CLONE_NEWUSER))
+		return -1;
+
+	if (write_file("/proc/self/setgroups", "deny", sizeof("deny") - 1) &&
+	    errno != ENOENT)
+		return -1;
+
+	snprintf(map, sizeof(map), "0 %d 1", uid);
+	if (write_file("/proc/self/uid_map", map, strlen(map)))
+		return -1;
+
+
+	snprintf(map, sizeof(map), "0 %d 1", gid);
+	if (write_file("/proc/self/gid_map", map, strlen(map)))
+		return -1;
+
+	if (setgid(0))
+		return -1;
+
+	if (setuid(0))
+		return -1;
+
+	return 0;
+}
+
+static int prepare_unpriv_mountns(void)
+{
+	if (create_and_enter_userns())
+		return -1;
+
+	if (unshare(CLONE_NEWNS))
+		return -1;
+
+	if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0))
+		return -1;
+
+	return 0;
+}
+
+static int read_mnt_flags(const char *path)
+{
+	int ret;
+	struct statvfs stat;
+	unsigned int mnt_flags;
+
+	ret = statvfs(path, &stat);
+	if (ret != 0)
+		return -EINVAL;
+
+	if (stat.f_flag &
+	    ~(ST_RDONLY | ST_NOSUID | ST_NODEV | ST_NOEXEC | ST_NOATIME |
+	      ST_NODIRATIME | ST_RELATIME | ST_SYNCHRONOUS | ST_MANDLOCK))
+		return -EINVAL;
+
+	mnt_flags = 0;
+	if (stat.f_flag & ST_RDONLY)
+		mnt_flags |= MS_RDONLY;
+	if (stat.f_flag & ST_NOSUID)
+		mnt_flags |= MS_NOSUID;
+	if (stat.f_flag & ST_NODEV)
+		mnt_flags |= MS_NODEV;
+	if (stat.f_flag & ST_NOEXEC)
+		mnt_flags |= MS_NOEXEC;
+	if (stat.f_flag & ST_NOATIME)
+		mnt_flags |= MS_NOATIME;
+	if (stat.f_flag & ST_NODIRATIME)
+		mnt_flags |= MS_NODIRATIME;
+	if (stat.f_flag & ST_RELATIME)
+		mnt_flags |= MS_RELATIME;
+	if (stat.f_flag & ST_SYNCHRONOUS)
+		mnt_flags |= MS_SYNCHRONOUS;
+	if (stat.f_flag & ST_MANDLOCK)
+		mnt_flags |= ST_MANDLOCK;
+
+	return mnt_flags;
+}
+
+static char *get_field(char *src, int nfields)
+{
+	int i;
+	char *p = src;
+
+	for (i = 0; i < nfields; i++) {
+		while (*p && *p != ' ' && *p != '\t')
+			p++;
+
+		if (!*p)
+			break;
+
+		p++;
+	}
+
+	return p;
+}
+
+static void null_endofword(char *word)
+{
+	while (*word && *word != ' ' && *word != '\t')
+		word++;
+	*word = '\0';
+}
+
+static bool is_shared_mount(const char *path)
+{
+	size_t len = 0;
+	char *line = NULL;
+	FILE *f = NULL;
+
+	f = fopen("/proc/self/mountinfo", "re");
+	if (!f)
+		return false;
+
+	while (getline(&line, &len, f) != -1) {
+		char *opts, *target;
+
+		target = get_field(line, 4);
+		if (!target)
+			continue;
+
+		opts = get_field(target, 2);
+		if (!opts)
+			continue;
+
+		null_endofword(target);
+
+		if (strcmp(target, path) != 0)
+			continue;
+
+		null_endofword(opts);
+		if (strstr(opts, "shared:"))
+			return true;
+	}
+
+	free(line);
+	fclose(f);
+
+	return false;
+}
+
+static void *mount_setattr_thread(void *data)
+{
+	struct mount_attr attr = {
+		.attr_set	= MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID,
+		.attr_clr	= 0,
+		.propagation	= MS_SHARED,
+	};
+
+	if (sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)))
+		pthread_exit(int_to_ptr(-1));
+
+	pthread_exit(int_to_ptr(0));
+}
+
+/* Attempt to de-conflict with the selftests tree. */
+#ifndef SKIP
+#define SKIP(s, ...)	XFAIL(s, ##__VA_ARGS__)
+#endif
+
+static bool mount_setattr_supported(void)
+{
+	int ret;
+
+	ret = sys_mount_setattr(-EBADF, "", AT_EMPTY_PATH, NULL, 0);
+	if (ret < 0 && errno == ENOSYS)
+		return false;
+
+	return true;
+}
+
+FIXTURE(mount_setattr) {
+};
+
+FIXTURE_SETUP(mount_setattr)
+{
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	ASSERT_EQ(prepare_unpriv_mountns(), 0);
+
+	(void)umount2("/mnt", MNT_DETACH);
+	(void)umount2("/tmp", MNT_DETACH);
+
+	ASSERT_EQ(mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/tmp/B", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/tmp/B", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/tmp/B/BB", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/tmp/B/BB", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/mnt/A", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/mnt/A", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/mnt/A/AA", 0777), 0);
+
+	ASSERT_EQ(mount("/tmp", "/mnt/A/AA", NULL, MS_BIND | MS_REC, NULL), 0);
+
+	ASSERT_EQ(mkdir("/mnt/B", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/mnt/B", "ramfs",
+			MS_NOATIME | MS_NODEV | MS_NOSUID, 0), 0);
+
+	ASSERT_EQ(mkdir("/mnt/B/BB", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/tmp/B/BB", "devpts",
+			MS_RELATIME | MS_NOEXEC | MS_RDONLY, 0), 0);
+}
+
+FIXTURE_TEARDOWN(mount_setattr)
+{
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	(void)umount2("/mnt/A", MNT_DETACH);
+	(void)umount2("/tmp", MNT_DETACH);
+}
+
+TEST_F(mount_setattr, invalid_attributes)
+{
+	struct mount_attr invalid_attr = {
+		.attr_set = (1U << 31),
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+				    sizeof(invalid_attr)), 0);
+
+	invalid_attr.attr_set	= 0;
+	invalid_attr.attr_clr	= (1U << 31);
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+				    sizeof(invalid_attr)), 0);
+
+	invalid_attr.attr_clr		= 0;
+	invalid_attr.propagation	= (1U << 31);
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+				    sizeof(invalid_attr)), 0);
+
+	invalid_attr.attr_set		= (1U << 31);
+	invalid_attr.attr_clr		= (1U << 31);
+	invalid_attr.propagation	= (1U << 31);
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+				    sizeof(invalid_attr)), 0);
+
+	ASSERT_NE(sys_mount_setattr(-1, "mnt/A", AT_RECURSIVE, &invalid_attr,
+				    sizeof(invalid_attr)), 0);
+}
+
+TEST_F(mount_setattr, extensibility)
+{
+	unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+	char *s = "dummy";
+	struct mount_attr invalid_attr = {};
+	struct mount_attr_large {
+		struct mount_attr attr1;
+		struct mount_attr attr2;
+		struct mount_attr attr3;
+	} large_attr = {};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	old_flags = read_mnt_flags("/mnt/A");
+	ASSERT_GT(old_flags, 0);
+
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, NULL,
+				    sizeof(invalid_attr)), 0);
+	ASSERT_EQ(errno, EFAULT);
+
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, (void *)s,
+				    sizeof(invalid_attr)), 0);
+	ASSERT_EQ(errno, EINVAL);
+
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, 0), 0);
+	ASSERT_EQ(errno, EINVAL);
+
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+				    sizeof(invalid_attr) / 2), 0);
+	ASSERT_EQ(errno, EINVAL);
+
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+				    sizeof(invalid_attr) / 2), 0);
+	ASSERT_EQ(errno, EINVAL);
+
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE,
+				    (void *)&large_attr, sizeof(large_attr)), 0);
+
+	large_attr.attr3.attr_set = MOUNT_ATTR_RDONLY;
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE,
+				    (void *)&large_attr, sizeof(large_attr)), 0);
+
+	large_attr.attr3.attr_set = 0;
+	large_attr.attr1.attr_set = MOUNT_ATTR_RDONLY;
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE,
+				    (void *)&large_attr, sizeof(large_attr)), 0);
+
+	expected_flags = old_flags;
+	expected_flags |= MS_RDONLY;
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+}
+
+TEST_F(mount_setattr, basic)
+{
+	unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+	struct mount_attr attr = {
+		.attr_set	= MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME,
+		.attr_clr	= MOUNT_ATTR__ATIME,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	old_flags = read_mnt_flags("/mnt/A");
+	ASSERT_GT(old_flags, 0);
+
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", 0, &attr, sizeof(attr)), 0);
+
+	expected_flags = old_flags;
+	expected_flags |= MS_RDONLY;
+	expected_flags |= MS_NOEXEC;
+	expected_flags &= ~MS_NOATIME;
+	expected_flags |= MS_RELATIME;
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, old_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, old_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, old_flags);
+}
+
+TEST_F(mount_setattr, basic_recursive)
+{
+	int fd;
+	unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+	struct mount_attr attr = {
+		.attr_set	= MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME,
+		.attr_clr	= MOUNT_ATTR__ATIME,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	old_flags = read_mnt_flags("/mnt/A");
+	ASSERT_GT(old_flags, 0);
+
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags = old_flags;
+	expected_flags |= MS_RDONLY;
+	expected_flags |= MS_NOEXEC;
+	expected_flags &= ~MS_NOATIME;
+	expected_flags |= MS_RELATIME;
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	memset(&attr, 0, sizeof(attr));
+	attr.attr_clr = MOUNT_ATTR_RDONLY;
+	attr.propagation = MS_SHARED;
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags &= ~MS_RDONLY;
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true);
+
+	fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777);
+	ASSERT_GE(fd, 0);
+
+	/*
+	 * We're holding a fd open for writing so this needs to fail somewhere
+	 * in the middle and the mount options need to be unchanged.
+	 */
+	attr.attr_set = MOUNT_ATTR_RDONLY;
+	ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true);
+
+	EXPECT_EQ(close(fd), 0);
+}
+
+TEST_F(mount_setattr, mount_has_writers)
+{
+	int fd, dfd;
+	unsigned int old_flags = 0, new_flags = 0;
+	struct mount_attr attr = {
+		.attr_set	= MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME,
+		.attr_clr	= MOUNT_ATTR__ATIME,
+		.propagation	= MS_SHARED,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	old_flags = read_mnt_flags("/mnt/A");
+	ASSERT_GT(old_flags, 0);
+
+	fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777);
+	ASSERT_GE(fd, 0);
+
+	/*
+	 * We're holding a fd open to a mount somwhere in the middle so this
+	 * needs to fail somewhere in the middle. After this the mount options
+	 * need to be unchanged.
+	 */
+	ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, old_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A"), false);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, old_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA"), false);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, old_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), false);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, old_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), false);
+
+	dfd = open("/mnt/A/AA/B", O_DIRECTORY | O_CLOEXEC);
+	ASSERT_GE(dfd, 0);
+	EXPECT_EQ(fsync(dfd), 0);
+	EXPECT_EQ(close(dfd), 0);
+
+	EXPECT_EQ(fsync(fd), 0);
+	EXPECT_EQ(close(fd), 0);
+
+	/* All writers are gone so this should succeed. */
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+}
+
+TEST_F(mount_setattr, mixed_mount_options)
+{
+	unsigned int old_flags1 = 0, old_flags2 = 0, new_flags = 0, expected_flags = 0;
+	struct mount_attr attr = {
+		.attr_clr = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME,
+		.attr_set = MOUNT_ATTR_RELATIME,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	old_flags1 = read_mnt_flags("/mnt/B");
+	ASSERT_GT(old_flags1, 0);
+
+	old_flags2 = read_mnt_flags("/mnt/B/BB");
+	ASSERT_GT(old_flags2, 0);
+
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/B", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags = old_flags2;
+	expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID);
+	expected_flags |= MS_RELATIME;
+
+	new_flags = read_mnt_flags("/mnt/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	expected_flags = old_flags2;
+	expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID);
+	expected_flags |= MS_RELATIME;
+
+	new_flags = read_mnt_flags("/mnt/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+}
+
+TEST_F(mount_setattr, time_changes)
+{
+	unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+	struct mount_attr attr = {
+		.attr_set	= MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	attr.attr_set = MOUNT_ATTR_STRICTATIME;
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME;
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME;
+	attr.attr_clr = MOUNT_ATTR__ATIME;
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	attr.attr_set = 0;
+	attr.attr_clr = MOUNT_ATTR_STRICTATIME;
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	attr.attr_clr = MOUNT_ATTR_NOATIME;
+	ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	old_flags = read_mnt_flags("/mnt/A");
+	ASSERT_GT(old_flags, 0);
+
+	attr.attr_set = MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME;
+	attr.attr_clr = MOUNT_ATTR__ATIME;
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags = old_flags;
+	expected_flags |= MS_NOATIME;
+	expected_flags |= MS_NODIRATIME;
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	memset(&attr, 0, sizeof(attr));
+	attr.attr_set &= ~MOUNT_ATTR_NOATIME;
+	attr.attr_set |= MOUNT_ATTR_RELATIME;
+	attr.attr_clr |= MOUNT_ATTR__ATIME;
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags &= ~MS_NOATIME;
+	expected_flags |= MS_RELATIME;
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	memset(&attr, 0, sizeof(attr));
+	attr.attr_set &= ~MOUNT_ATTR_RELATIME;
+	attr.attr_set |= MOUNT_ATTR_STRICTATIME;
+	attr.attr_clr |= MOUNT_ATTR__ATIME;
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags &= ~MS_RELATIME;
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	memset(&attr, 0, sizeof(attr));
+	attr.attr_set &= ~MOUNT_ATTR_STRICTATIME;
+	attr.attr_set |= MOUNT_ATTR_NOATIME;
+	attr.attr_clr |= MOUNT_ATTR__ATIME;
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags |= MS_NOATIME;
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	memset(&attr, 0, sizeof(attr));
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	memset(&attr, 0, sizeof(attr));
+	attr.attr_clr = MOUNT_ATTR_NODIRATIME;
+	ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+	expected_flags &= ~MS_NODIRATIME;
+
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+}
+
+TEST_F(mount_setattr, multi_threaded)
+{
+	int i, j, nthreads, ret = 0;
+	unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+	pthread_attr_t pattr;
+	pthread_t threads[DEFAULT_THREADS];
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	old_flags = read_mnt_flags("/mnt/A");
+	ASSERT_GT(old_flags, 0);
+
+	/* Try to change mount options from multiple threads. */
+	nthreads = get_nprocs_conf();
+	if (nthreads > DEFAULT_THREADS)
+		nthreads = DEFAULT_THREADS;
+
+	pthread_attr_init(&pattr);
+	for (i = 0; i < nthreads; i++)
+		ASSERT_EQ(pthread_create(&threads[i], &pattr, mount_setattr_thread, NULL), 0);
+
+	for (j = 0; j < i; j++) {
+		void *retptr = NULL;
+
+		EXPECT_EQ(pthread_join(threads[j], &retptr), 0);
+
+		ret += ptr_to_int(retptr);
+		EXPECT_EQ(ret, 0);
+	}
+	pthread_attr_destroy(&pattr);
+
+	ASSERT_EQ(ret, 0);
+
+	expected_flags = old_flags;
+	expected_flags |= MS_RDONLY;
+	expected_flags |= MS_NOSUID;
+	new_flags = read_mnt_flags("/mnt/A");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true);
+
+	new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+	ASSERT_EQ(new_flags, expected_flags);
+
+	ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true);
+}
+
+TEST_F(mount_setattr, wrong_user_namespace)
+{
+	int ret;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_RDONLY,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	EXPECT_EQ(create_and_enter_userns(), 0);
+	ret = sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr));
+	ASSERT_LT(ret, 0);
+	ASSERT_EQ(errno, EPERM);
+}
+
+TEST_F(mount_setattr, wrong_mount_namespace)
+{
+	int fd, ret;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_RDONLY,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	fd = open("/mnt/A", O_DIRECTORY | O_CLOEXEC);
+	ASSERT_GE(fd, 0);
+
+	ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+	ret = sys_mount_setattr(fd, "", AT_EMPTY_PATH | AT_RECURSIVE, &attr, sizeof(attr));
+	ASSERT_LT(ret, 0);
+	ASSERT_EQ(errno, EINVAL);
+}
+
+FIXTURE(mount_setattr_idmapped) {
+};
+
+FIXTURE_SETUP(mount_setattr_idmapped)
+{
+	int img_fd = -EBADF;
+
+	ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+	ASSERT_EQ(mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0), 0);
+
+	(void)umount2("/mnt", MNT_DETACH);
+	(void)umount2("/tmp", MNT_DETACH);
+
+	ASSERT_EQ(mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/tmp/B", 0777), 0);
+	ASSERT_EQ(mknodat(-EBADF, "/tmp/B/b", S_IFREG | 0644, 0), 0);
+	ASSERT_EQ(chown("/tmp/B/b", 0, 0), 0);
+
+	ASSERT_EQ(mount("testing", "/tmp/B", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/tmp/B/BB", 0777), 0);
+	ASSERT_EQ(mknodat(-EBADF, "/tmp/B/BB/b", S_IFREG | 0644, 0), 0);
+	ASSERT_EQ(chown("/tmp/B/BB/b", 0, 0), 0);
+
+	ASSERT_EQ(mount("testing", "/tmp/B/BB", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/mnt/A", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/mnt/A", "tmpfs", MS_NOATIME | MS_NODEV,
+			"size=100000,mode=700"), 0);
+
+	ASSERT_EQ(mkdir("/mnt/A/AA", 0777), 0);
+
+	ASSERT_EQ(mount("/tmp", "/mnt/A/AA", NULL, MS_BIND | MS_REC, NULL), 0);
+
+	ASSERT_EQ(mkdir("/mnt/B", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/mnt/B", "ramfs",
+			MS_NOATIME | MS_NODEV | MS_NOSUID, 0), 0);
+
+	ASSERT_EQ(mkdir("/mnt/B/BB", 0777), 0);
+
+	ASSERT_EQ(mount("testing", "/tmp/B/BB", "devpts",
+			MS_RELATIME | MS_NOEXEC | MS_RDONLY, 0), 0);
+
+	ASSERT_EQ(mkdir("/mnt/C", 0777), 0);
+	ASSERT_EQ(mkdir("/mnt/D", 0777), 0);
+	img_fd = openat(-EBADF, "/mnt/C/ext4.img", O_CREAT | O_WRONLY, 0600);
+	ASSERT_GE(img_fd, 0);
+	ASSERT_EQ(ftruncate(img_fd, 1024 * 2048), 0);
+	ASSERT_EQ(system("mkfs.ext4 -q /mnt/C/ext4.img"), 0);
+	ASSERT_EQ(system("mount -o loop -t ext4 /mnt/C/ext4.img /mnt/D/"), 0);
+	ASSERT_EQ(close(img_fd), 0);
+}
+
+FIXTURE_TEARDOWN(mount_setattr_idmapped)
+{
+	(void)umount2("/mnt/A", MNT_DETACH);
+	(void)umount2("/tmp", MNT_DETACH);
+}
+
+/**
+ * Validate that negative fd values are rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_negative)
+{
+	struct mount_attr attr = {
+		.attr_set	= MOUNT_ATTR_IDMAP,
+		.userns_fd	= -EBADF,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	ASSERT_NE(sys_mount_setattr(-1, "/", 0, &attr, sizeof(attr)), 0) {
+		TH_LOG("failure: created idmapped mount with negative fd");
+	}
+}
+
+/**
+ * Validate that excessively large fd values are rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_large)
+{
+	struct mount_attr attr = {
+		.attr_set	= MOUNT_ATTR_IDMAP,
+		.userns_fd	= INT64_MAX,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	ASSERT_NE(sys_mount_setattr(-1, "/", 0, &attr, sizeof(attr)), 0) {
+		TH_LOG("failure: created idmapped mount with too large fd value");
+	}
+}
+
+/**
+ * Validate that closed fd values are rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_closed)
+{
+	int fd;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	fd = open("/dev/null", O_RDONLY | O_CLOEXEC);
+	ASSERT_GE(fd, 0);
+	ASSERT_GE(close(fd), 0);
+
+	attr.userns_fd = fd;
+	ASSERT_NE(sys_mount_setattr(-1, "/", 0, &attr, sizeof(attr)), 0) {
+		TH_LOG("failure: created idmapped mount with closed fd");
+	}
+}
+
+/**
+ * Validate that the initial user namespace is rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_initial_userns)
+{
+	int open_tree_fd = -EBADF;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+				     AT_NO_AUTOMOUNT |
+				     AT_SYMLINK_NOFOLLOW |
+				     OPEN_TREE_CLOEXEC | OPEN_TREE_CLONE);
+	ASSERT_GE(open_tree_fd, 0);
+
+	attr.userns_fd = open("/proc/1/ns/user", O_RDONLY | O_CLOEXEC);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+	ASSERT_EQ(errno, EPERM);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+	ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+static int map_ids(pid_t pid, unsigned long nsid, unsigned long hostid,
+		   unsigned long range)
+{
+	char map[100], procfile[256];
+
+	snprintf(procfile, sizeof(procfile), "/proc/%d/uid_map", pid);
+	snprintf(map, sizeof(map), "%lu %lu %lu", nsid, hostid, range);
+	if (write_file(procfile, map, strlen(map)))
+		return -1;
+
+
+	snprintf(procfile, sizeof(procfile), "/proc/%d/gid_map", pid);
+	snprintf(map, sizeof(map), "%lu %lu %lu", nsid, hostid, range);
+	if (write_file(procfile, map, strlen(map)))
+		return -1;
+
+	return 0;
+}
+
+#define __STACK_SIZE (8 * 1024 * 1024)
+static pid_t do_clone(int (*fn)(void *), void *arg, int flags)
+{
+	void *stack;
+
+	stack = malloc(__STACK_SIZE);
+	if (!stack)
+		return -ENOMEM;
+
+#ifdef __ia64__
+	return __clone2(fn, stack, __STACK_SIZE, flags | SIGCHLD, arg, NULL);
+#else
+	return clone(fn, stack + __STACK_SIZE, flags | SIGCHLD, arg, NULL);
+#endif
+}
+
+static int get_userns_fd_cb(void *data)
+{
+	return kill(getpid(), SIGSTOP);
+}
+
+static int wait_for_pid(pid_t pid)
+{
+	int status, ret;
+
+again:
+	ret = waitpid(pid, &status, 0);
+	if (ret == -1) {
+		if (errno == EINTR)
+			goto again;
+
+		return -1;
+	}
+
+	if (!WIFEXITED(status))
+		return -1;
+
+	return WEXITSTATUS(status);
+}
+
+static int get_userns_fd(unsigned long nsid, unsigned long hostid, unsigned long range)
+{
+	int ret;
+	pid_t pid;
+	char path[256];
+
+	pid = do_clone(get_userns_fd_cb, NULL, CLONE_NEWUSER);
+	if (pid < 0)
+		return -errno;
+
+	ret = map_ids(pid, nsid, hostid, range);
+	if (ret < 0)
+		return ret;
+
+	snprintf(path, sizeof(path), "/proc/%d/ns/user", pid);
+	ret = open(path, O_RDONLY | O_CLOEXEC);
+	kill(pid, SIGKILL);
+	wait_for_pid(pid);
+	return ret;
+}
+
+/**
+ * Validate that an attached mount in our mount namespace can be idmapped.
+ * (The kernel enforces that the mount's mount namespace and the caller's mount
+ *  namespace match.)
+ */
+TEST_F(mount_setattr_idmapped, attached_mount_inside_current_mount_namespace)
+{
+	int open_tree_fd = -EBADF;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+				     AT_EMPTY_PATH |
+				     AT_NO_AUTOMOUNT |
+				     AT_SYMLINK_NOFOLLOW |
+				     OPEN_TREE_CLOEXEC);
+	ASSERT_GE(open_tree_fd, 0);
+
+	attr.userns_fd	= get_userns_fd(0, 10000, 10000);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_EQ(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+	ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that idmapping a mount is rejected if the mount's mount namespace
+ * and our mount namespace don't match.
+ * (The kernel enforces that the mount's mount namespace and the caller's mount
+ *  namespace match.)
+ */
+TEST_F(mount_setattr_idmapped, attached_mount_outside_current_mount_namespace)
+{
+	int open_tree_fd = -EBADF;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+				     AT_EMPTY_PATH |
+				     AT_NO_AUTOMOUNT |
+				     AT_SYMLINK_NOFOLLOW |
+				     OPEN_TREE_CLOEXEC);
+	ASSERT_GE(open_tree_fd, 0);
+
+	ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+	attr.userns_fd	= get_userns_fd(0, 10000, 10000);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr,
+				    sizeof(attr)), 0);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+	ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that an attached mount in our mount namespace can be idmapped.
+ */
+TEST_F(mount_setattr_idmapped, detached_mount_inside_current_mount_namespace)
+{
+	int open_tree_fd = -EBADF;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+				     AT_EMPTY_PATH |
+				     AT_NO_AUTOMOUNT |
+				     AT_SYMLINK_NOFOLLOW |
+				     OPEN_TREE_CLOEXEC |
+				     OPEN_TREE_CLONE);
+	ASSERT_GE(open_tree_fd, 0);
+
+	/* Changing mount properties on a detached mount. */
+	attr.userns_fd	= get_userns_fd(0, 10000, 10000);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_EQ(sys_mount_setattr(open_tree_fd, "",
+				    AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+	ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that a detached mount not in our mount namespace can be idmapped.
+ */
+TEST_F(mount_setattr_idmapped, detached_mount_outside_current_mount_namespace)
+{
+	int open_tree_fd = -EBADF;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+				     AT_EMPTY_PATH |
+				     AT_NO_AUTOMOUNT |
+				     AT_SYMLINK_NOFOLLOW |
+				     OPEN_TREE_CLOEXEC |
+				     OPEN_TREE_CLONE);
+	ASSERT_GE(open_tree_fd, 0);
+
+	ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+	/* Changing mount properties on a detached mount. */
+	attr.userns_fd	= get_userns_fd(0, 10000, 10000);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_EQ(sys_mount_setattr(open_tree_fd, "",
+				    AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+	ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that currently changing the idmapping of an idmapped mount fails.
+ */
+TEST_F(mount_setattr_idmapped, change_idmapping)
+{
+	int open_tree_fd = -EBADF;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+				     AT_EMPTY_PATH |
+				     AT_NO_AUTOMOUNT |
+				     AT_SYMLINK_NOFOLLOW |
+				     OPEN_TREE_CLOEXEC |
+				     OPEN_TREE_CLONE);
+	ASSERT_GE(open_tree_fd, 0);
+
+	attr.userns_fd	= get_userns_fd(0, 10000, 10000);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_EQ(sys_mount_setattr(open_tree_fd, "",
+				    AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+
+	/* Change idmapping on a detached mount that is already idmapped. */
+	attr.userns_fd	= get_userns_fd(0, 20000, 10000);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+	ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+static bool expected_uid_gid(int dfd, const char *path, int flags,
+			     uid_t expected_uid, gid_t expected_gid)
+{
+	int ret;
+	struct stat st;
+
+	ret = fstatat(dfd, path, &st, flags);
+	if (ret < 0)
+		return false;
+
+	return st.st_uid == expected_uid && st.st_gid == expected_gid;
+}
+
+TEST_F(mount_setattr_idmapped, idmap_mount_tree_invalid)
+{
+	int open_tree_fd = -EBADF;
+	struct mount_attr attr = {
+		.attr_set = MOUNT_ATTR_IDMAP,
+	};
+
+	if (!mount_setattr_supported())
+		SKIP(return, "mount_setattr syscall not supported");
+
+	ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/b", 0, 0, 0), 0);
+	ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/BB/b", 0, 0, 0), 0);
+
+	open_tree_fd = sys_open_tree(-EBADF, "/mnt/A",
+				     AT_RECURSIVE |
+				     AT_EMPTY_PATH |
+				     AT_NO_AUTOMOUNT |
+				     AT_SYMLINK_NOFOLLOW |
+				     OPEN_TREE_CLOEXEC |
+				     OPEN_TREE_CLONE);
+	ASSERT_GE(open_tree_fd, 0);
+
+	attr.userns_fd	= get_userns_fd(0, 10000, 10000);
+	ASSERT_GE(attr.userns_fd, 0);
+	ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+	ASSERT_EQ(close(attr.userns_fd), 0);
+	ASSERT_EQ(close(open_tree_fd), 0);
+
+	ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/b", 0, 0, 0), 0);
+	ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/BB/b", 0, 0, 0), 0);
+	ASSERT_EQ(expected_uid_gid(open_tree_fd, "B/b", 0, 0, 0), 0);
+	ASSERT_EQ(expected_uid_gid(open_tree_fd, "B/BB/b", 0, 0, 0), 0);
+}
+
+TEST_HARNESS_MAIN