kernel-ark/fs/hfsplus/ioctl.c
Satyam Sharma 3bd858ab1c Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check
Introduce is_owner_or_cap() macro in fs.h, and convert over relevant
users to it. This is done because we want to avoid bugs in the future
where we check for only effective fsuid of the current task against a
file's owning uid, without simultaneously checking for CAP_FOWNER as
well, thus violating its semantics.
[ XFS uses special macros and structures, and in general looked ...
untouchable, so we leave it alone -- but it has been looked over. ]

The (current->fsuid != inode->i_uid) check in generic_permission() and
exec_permission_lite() is left alone, because those operations are
covered by CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH. Similarly operations
falling under the purview of CAP_CHOWN and CAP_LEASE are also left alone.

Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Cc: Al Viro <viro@ftp.linux.org.uk>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 12:00:03 -07:00

189 lines
4.7 KiB
C

/*
* linux/fs/hfsplus/ioctl.c
*
* Copyright (C) 2003
* Ethan Benson <erbenson@alaska.net>
* partially derived from linux/fs/ext2/ioctl.c
* Copyright (C) 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* hfsplus ioctls
*/
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/xattr.h>
#include <asm/uaccess.h>
#include "hfsplus_fs.h"
int hfsplus_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
unsigned long arg)
{
unsigned int flags;
switch (cmd) {
case HFSPLUS_IOC_EXT2_GETFLAGS:
flags = 0;
if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_IMMUTABLE)
flags |= FS_IMMUTABLE_FL; /* EXT2_IMMUTABLE_FL */
if (HFSPLUS_I(inode).rootflags & HFSPLUS_FLG_APPEND)
flags |= FS_APPEND_FL; /* EXT2_APPEND_FL */
if (HFSPLUS_I(inode).userflags & HFSPLUS_FLG_NODUMP)
flags |= FS_NODUMP_FL; /* EXT2_NODUMP_FL */
return put_user(flags, (int __user *)arg);
case HFSPLUS_IOC_EXT2_SETFLAGS: {
if (IS_RDONLY(inode))
return -EROFS;
if (!is_owner_or_cap(inode))
return -EACCES;
if (get_user(flags, (int __user *)arg))
return -EFAULT;
if (flags & (FS_IMMUTABLE_FL|FS_APPEND_FL) ||
HFSPLUS_I(inode).rootflags & (HFSPLUS_FLG_IMMUTABLE|HFSPLUS_FLG_APPEND)) {
if (!capable(CAP_LINUX_IMMUTABLE))
return -EPERM;
}
/* don't silently ignore unsupported ext2 flags */
if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL))
return -EOPNOTSUPP;
if (flags & FS_IMMUTABLE_FL) { /* EXT2_IMMUTABLE_FL */
inode->i_flags |= S_IMMUTABLE;
HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_IMMUTABLE;
} else {
inode->i_flags &= ~S_IMMUTABLE;
HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_IMMUTABLE;
}
if (flags & FS_APPEND_FL) { /* EXT2_APPEND_FL */
inode->i_flags |= S_APPEND;
HFSPLUS_I(inode).rootflags |= HFSPLUS_FLG_APPEND;
} else {
inode->i_flags &= ~S_APPEND;
HFSPLUS_I(inode).rootflags &= ~HFSPLUS_FLG_APPEND;
}
if (flags & FS_NODUMP_FL) /* EXT2_NODUMP_FL */
HFSPLUS_I(inode).userflags |= HFSPLUS_FLG_NODUMP;
else
HFSPLUS_I(inode).userflags &= ~HFSPLUS_FLG_NODUMP;
inode->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
return 0;
}
default:
return -ENOTTY;
}
}
int hfsplus_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
struct inode *inode = dentry->d_inode;
struct hfs_find_data fd;
hfsplus_cat_entry entry;
struct hfsplus_cat_file *file;
int res;
if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
return -EOPNOTSUPP;
res = hfs_find_init(HFSPLUS_SB(inode->i_sb).cat_tree, &fd);
if (res)
return res;
res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
if (res)
goto out;
hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
sizeof(struct hfsplus_cat_file));
file = &entry.file;
if (!strcmp(name, "hfs.type")) {
if (size == 4)
memcpy(&file->user_info.fdType, value, 4);
else
res = -ERANGE;
} else if (!strcmp(name, "hfs.creator")) {
if (size == 4)
memcpy(&file->user_info.fdCreator, value, 4);
else
res = -ERANGE;
} else
res = -EOPNOTSUPP;
if (!res)
hfs_bnode_write(fd.bnode, &entry, fd.entryoffset,
sizeof(struct hfsplus_cat_file));
out:
hfs_find_exit(&fd);
return res;
}
ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
void *value, size_t size)
{
struct inode *inode = dentry->d_inode;
struct hfs_find_data fd;
hfsplus_cat_entry entry;
struct hfsplus_cat_file *file;
ssize_t res = 0;
if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
return -EOPNOTSUPP;
if (size) {
res = hfs_find_init(HFSPLUS_SB(inode->i_sb).cat_tree, &fd);
if (res)
return res;
res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
if (res)
goto out;
hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
sizeof(struct hfsplus_cat_file));
}
file = &entry.file;
if (!strcmp(name, "hfs.type")) {
if (size >= 4) {
memcpy(value, &file->user_info.fdType, 4);
res = 4;
} else
res = size ? -ERANGE : 4;
} else if (!strcmp(name, "hfs.creator")) {
if (size >= 4) {
memcpy(value, &file->user_info.fdCreator, 4);
res = 4;
} else
res = size ? -ERANGE : 4;
} else
res = -ENODATA;
out:
if (size)
hfs_find_exit(&fd);
return res;
}
#define HFSPLUS_ATTRLIST_SIZE (sizeof("hfs.creator")+sizeof("hfs.type"))
ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
struct inode *inode = dentry->d_inode;
if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
return -EOPNOTSUPP;
if (!buffer || !size)
return HFSPLUS_ATTRLIST_SIZE;
if (size < HFSPLUS_ATTRLIST_SIZE)
return -ERANGE;
strcpy(buffer, "hfs.type");
strcpy(buffer + sizeof("hfs.type"), "hfs.creator");
return HFSPLUS_ATTRLIST_SIZE;
}