Currently the IPC namespace management code is spread over the ipc/*.c files. I moved this code into ipc/namespace.c file which is compiled out when needed. The linux/ipc_namespace.h file is used to store the prototypes of the functions in namespace.c and the stubs for NAMESPACES=n case. This is done so, because the stub for copy_ipc_namespace requires the knowledge of the CLONE_NEWIPC flag, which is in sched.h. But the linux/ipc.h file itself in included into many many .c files via the sys.h->sem.h sequence so adding the sched.h into it will make all these .c depend on sched.h which is not that good. On the other hand the knowledge about the namespaces stuff is required in 4 .c files only. Besides, this patch compiles out some auxiliary functions from ipc/sem.c, msg.c and shm.c files. It turned out that moving these functions into namespaces.c is not that easy because they use many other calls and macros from the original file. Moving them would make this patch complicated. On the other hand all these functions can be consolidated, so I will send a separate patch doing this a bit later. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1197 lines
28 KiB
C
1197 lines
28 KiB
C
/*
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* linux/ipc/shm.c
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* Copyright (C) 1992, 1993 Krishna Balasubramanian
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* Many improvements/fixes by Bruno Haible.
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* Replaced `struct shm_desc' by `struct vm_area_struct', July 1994.
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* Fixed the shm swap deallocation (shm_unuse()), August 1998 Andrea Arcangeli.
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*
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* /proc/sysvipc/shm support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
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* BIGMEM support, Andrea Arcangeli <andrea@suse.de>
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* SMP thread shm, Jean-Luc Boyard <jean-luc.boyard@siemens.fr>
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* HIGHMEM support, Ingo Molnar <mingo@redhat.com>
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* Make shmmax, shmall, shmmni sysctl'able, Christoph Rohland <cr@sap.com>
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* Shared /dev/zero support, Kanoj Sarcar <kanoj@sgi.com>
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* Move the mm functionality over to mm/shmem.c, Christoph Rohland <cr@sap.com>
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*
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* support for audit of ipc object properties and permission changes
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* Dustin Kirkland <dustin.kirkland@us.ibm.com>
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*
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* namespaces support
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* OpenVZ, SWsoft Inc.
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* Pavel Emelianov <xemul@openvz.org>
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*/
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#include <linux/slab.h>
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#include <linux/mm.h>
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#include <linux/hugetlb.h>
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#include <linux/shm.h>
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#include <linux/init.h>
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#include <linux/file.h>
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#include <linux/mman.h>
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#include <linux/shmem_fs.h>
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#include <linux/security.h>
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#include <linux/syscalls.h>
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#include <linux/audit.h>
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#include <linux/capability.h>
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#include <linux/ptrace.h>
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#include <linux/seq_file.h>
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#include <linux/rwsem.h>
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#include <linux/nsproxy.h>
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#include <linux/mount.h>
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#include <linux/ipc_namespace.h>
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#include <asm/uaccess.h>
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#include "util.h"
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struct shm_file_data {
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int id;
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struct ipc_namespace *ns;
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struct file *file;
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const struct vm_operations_struct *vm_ops;
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};
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#define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data))
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static const struct file_operations shm_file_operations;
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static struct vm_operations_struct shm_vm_ops;
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static struct ipc_ids init_shm_ids;
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#define shm_ids(ns) (*((ns)->ids[IPC_SHM_IDS]))
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#define shm_unlock(shp) \
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ipc_unlock(&(shp)->shm_perm)
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#define shm_buildid(id, seq) ipc_buildid(id, seq)
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static int newseg(struct ipc_namespace *, struct ipc_params *);
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static void shm_open(struct vm_area_struct *vma);
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static void shm_close(struct vm_area_struct *vma);
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static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
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#ifdef CONFIG_PROC_FS
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static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
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#endif
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static void __shm_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
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{
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ns->ids[IPC_SHM_IDS] = ids;
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ns->shm_ctlmax = SHMMAX;
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ns->shm_ctlall = SHMALL;
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ns->shm_ctlmni = SHMMNI;
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ns->shm_tot = 0;
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ipc_init_ids(ids);
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}
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/*
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* Called with shm_ids.rw_mutex (writer) and the shp structure locked.
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* Only shm_ids.rw_mutex remains locked on exit.
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*/
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static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
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{
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if (shp->shm_nattch){
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shp->shm_perm.mode |= SHM_DEST;
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/* Do not find it any more */
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shp->shm_perm.key = IPC_PRIVATE;
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shm_unlock(shp);
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} else
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shm_destroy(ns, shp);
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}
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#ifdef CONFIG_IPC_NS
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int shm_init_ns(struct ipc_namespace *ns)
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{
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struct ipc_ids *ids;
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ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
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if (ids == NULL)
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return -ENOMEM;
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__shm_init_ns(ns, ids);
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return 0;
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}
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void shm_exit_ns(struct ipc_namespace *ns)
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{
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struct shmid_kernel *shp;
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struct kern_ipc_perm *perm;
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int next_id;
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int total, in_use;
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down_write(&shm_ids(ns).rw_mutex);
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in_use = shm_ids(ns).in_use;
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for (total = 0, next_id = 0; total < in_use; next_id++) {
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perm = idr_find(&shm_ids(ns).ipcs_idr, next_id);
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if (perm == NULL)
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continue;
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ipc_lock_by_ptr(perm);
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shp = container_of(perm, struct shmid_kernel, shm_perm);
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do_shm_rmid(ns, shp);
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total++;
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}
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up_write(&shm_ids(ns).rw_mutex);
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kfree(ns->ids[IPC_SHM_IDS]);
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ns->ids[IPC_SHM_IDS] = NULL;
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}
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#endif
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void __init shm_init (void)
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{
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__shm_init_ns(&init_ipc_ns, &init_shm_ids);
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ipc_init_proc_interface("sysvipc/shm",
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" key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime\n",
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IPC_SHM_IDS, sysvipc_shm_proc_show);
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}
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/*
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* shm_lock_(check_)down routines are called in the paths where the rw_mutex
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* is held to protect access to the idr tree.
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*/
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static inline struct shmid_kernel *shm_lock_down(struct ipc_namespace *ns,
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int id)
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{
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struct kern_ipc_perm *ipcp = ipc_lock_down(&shm_ids(ns), id);
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if (IS_ERR(ipcp))
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return (struct shmid_kernel *)ipcp;
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return container_of(ipcp, struct shmid_kernel, shm_perm);
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}
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static inline struct shmid_kernel *shm_lock_check_down(
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struct ipc_namespace *ns,
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int id)
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{
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struct kern_ipc_perm *ipcp = ipc_lock_check_down(&shm_ids(ns), id);
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if (IS_ERR(ipcp))
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return (struct shmid_kernel *)ipcp;
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return container_of(ipcp, struct shmid_kernel, shm_perm);
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}
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/*
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* shm_lock_(check_) routines are called in the paths where the rw_mutex
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* is not held.
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*/
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static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
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{
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struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
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if (IS_ERR(ipcp))
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return (struct shmid_kernel *)ipcp;
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return container_of(ipcp, struct shmid_kernel, shm_perm);
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}
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static inline struct shmid_kernel *shm_lock_check(struct ipc_namespace *ns,
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int id)
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{
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struct kern_ipc_perm *ipcp = ipc_lock_check(&shm_ids(ns), id);
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if (IS_ERR(ipcp))
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return (struct shmid_kernel *)ipcp;
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return container_of(ipcp, struct shmid_kernel, shm_perm);
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}
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static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
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{
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ipc_rmid(&shm_ids(ns), &s->shm_perm);
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}
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static inline int shm_addid(struct ipc_namespace *ns, struct shmid_kernel *shp)
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{
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return ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni);
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}
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/* This is called by fork, once for every shm attach. */
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static void shm_open(struct vm_area_struct *vma)
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{
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struct file *file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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struct shmid_kernel *shp;
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shp = shm_lock(sfd->ns, sfd->id);
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BUG_ON(IS_ERR(shp));
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shp->shm_atim = get_seconds();
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shp->shm_lprid = task_tgid_vnr(current);
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shp->shm_nattch++;
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shm_unlock(shp);
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}
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/*
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* shm_destroy - free the struct shmid_kernel
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*
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* @ns: namespace
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* @shp: struct to free
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*
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* It has to be called with shp and shm_ids.rw_mutex (writer) locked,
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* but returns with shp unlocked and freed.
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*/
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static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
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{
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ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
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shm_rmid(ns, shp);
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shm_unlock(shp);
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if (!is_file_hugepages(shp->shm_file))
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shmem_lock(shp->shm_file, 0, shp->mlock_user);
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else
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user_shm_unlock(shp->shm_file->f_path.dentry->d_inode->i_size,
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shp->mlock_user);
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fput (shp->shm_file);
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security_shm_free(shp);
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ipc_rcu_putref(shp);
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}
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/*
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* remove the attach descriptor vma.
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* free memory for segment if it is marked destroyed.
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* The descriptor has already been removed from the current->mm->mmap list
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* and will later be kfree()d.
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*/
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static void shm_close(struct vm_area_struct *vma)
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{
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struct file * file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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struct shmid_kernel *shp;
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struct ipc_namespace *ns = sfd->ns;
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down_write(&shm_ids(ns).rw_mutex);
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/* remove from the list of attaches of the shm segment */
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shp = shm_lock_down(ns, sfd->id);
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BUG_ON(IS_ERR(shp));
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shp->shm_lprid = task_tgid_vnr(current);
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shp->shm_dtim = get_seconds();
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shp->shm_nattch--;
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if(shp->shm_nattch == 0 &&
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shp->shm_perm.mode & SHM_DEST)
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shm_destroy(ns, shp);
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else
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shm_unlock(shp);
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up_write(&shm_ids(ns).rw_mutex);
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}
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static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
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{
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struct file *file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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return sfd->vm_ops->fault(vma, vmf);
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}
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#ifdef CONFIG_NUMA
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static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
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{
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struct file *file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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int err = 0;
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if (sfd->vm_ops->set_policy)
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err = sfd->vm_ops->set_policy(vma, new);
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return err;
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}
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|
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static struct mempolicy *shm_get_policy(struct vm_area_struct *vma,
|
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unsigned long addr)
|
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{
|
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struct file *file = vma->vm_file;
|
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struct shm_file_data *sfd = shm_file_data(file);
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struct mempolicy *pol = NULL;
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if (sfd->vm_ops->get_policy)
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pol = sfd->vm_ops->get_policy(vma, addr);
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else if (vma->vm_policy)
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pol = vma->vm_policy;
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else
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pol = current->mempolicy;
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return pol;
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}
|
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#endif
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|
|
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static int shm_mmap(struct file * file, struct vm_area_struct * vma)
|
|
{
|
|
struct shm_file_data *sfd = shm_file_data(file);
|
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int ret;
|
|
|
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ret = sfd->file->f_op->mmap(sfd->file, vma);
|
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if (ret != 0)
|
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return ret;
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sfd->vm_ops = vma->vm_ops;
|
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#ifdef CONFIG_MMU
|
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BUG_ON(!sfd->vm_ops->fault);
|
|
#endif
|
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vma->vm_ops = &shm_vm_ops;
|
|
shm_open(vma);
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|
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return ret;
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}
|
|
|
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static int shm_release(struct inode *ino, struct file *file)
|
|
{
|
|
struct shm_file_data *sfd = shm_file_data(file);
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|
|
|
put_ipc_ns(sfd->ns);
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shm_file_data(file) = NULL;
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kfree(sfd);
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return 0;
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}
|
|
|
|
static int shm_fsync(struct file *file, struct dentry *dentry, int datasync)
|
|
{
|
|
int (*fsync) (struct file *, struct dentry *, int datasync);
|
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struct shm_file_data *sfd = shm_file_data(file);
|
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int ret = -EINVAL;
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|
|
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fsync = sfd->file->f_op->fsync;
|
|
if (fsync)
|
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ret = fsync(sfd->file, sfd->file->f_path.dentry, datasync);
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return ret;
|
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}
|
|
|
|
static unsigned long shm_get_unmapped_area(struct file *file,
|
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unsigned long addr, unsigned long len, unsigned long pgoff,
|
|
unsigned long flags)
|
|
{
|
|
struct shm_file_data *sfd = shm_file_data(file);
|
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return get_unmapped_area(sfd->file, addr, len, pgoff, flags);
|
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}
|
|
|
|
int is_file_shm_hugepages(struct file *file)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (file->f_op == &shm_file_operations) {
|
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struct shm_file_data *sfd;
|
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sfd = shm_file_data(file);
|
|
ret = is_file_hugepages(sfd->file);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations shm_file_operations = {
|
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.mmap = shm_mmap,
|
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.fsync = shm_fsync,
|
|
.release = shm_release,
|
|
.get_unmapped_area = shm_get_unmapped_area,
|
|
};
|
|
|
|
static struct vm_operations_struct shm_vm_ops = {
|
|
.open = shm_open, /* callback for a new vm-area open */
|
|
.close = shm_close, /* callback for when the vm-area is released */
|
|
.fault = shm_fault,
|
|
#if defined(CONFIG_NUMA)
|
|
.set_policy = shm_set_policy,
|
|
.get_policy = shm_get_policy,
|
|
#endif
|
|
};
|
|
|
|
/**
|
|
* newseg - Create a new shared memory segment
|
|
* @ns: namespace
|
|
* @params: ptr to the structure that contains key, size and shmflg
|
|
*
|
|
* Called with shm_ids.rw_mutex held as a writer.
|
|
*/
|
|
|
|
static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
|
|
{
|
|
key_t key = params->key;
|
|
int shmflg = params->flg;
|
|
size_t size = params->u.size;
|
|
int error;
|
|
struct shmid_kernel *shp;
|
|
int numpages = (size + PAGE_SIZE -1) >> PAGE_SHIFT;
|
|
struct file * file;
|
|
char name[13];
|
|
int id;
|
|
|
|
if (size < SHMMIN || size > ns->shm_ctlmax)
|
|
return -EINVAL;
|
|
|
|
if (ns->shm_tot + numpages > ns->shm_ctlall)
|
|
return -ENOSPC;
|
|
|
|
shp = ipc_rcu_alloc(sizeof(*shp));
|
|
if (!shp)
|
|
return -ENOMEM;
|
|
|
|
shp->shm_perm.key = key;
|
|
shp->shm_perm.mode = (shmflg & S_IRWXUGO);
|
|
shp->mlock_user = NULL;
|
|
|
|
shp->shm_perm.security = NULL;
|
|
error = security_shm_alloc(shp);
|
|
if (error) {
|
|
ipc_rcu_putref(shp);
|
|
return error;
|
|
}
|
|
|
|
sprintf (name, "SYSV%08x", key);
|
|
if (shmflg & SHM_HUGETLB) {
|
|
/* hugetlb_file_setup takes care of mlock user accounting */
|
|
file = hugetlb_file_setup(name, size);
|
|
shp->mlock_user = current->user;
|
|
} else {
|
|
int acctflag = VM_ACCOUNT;
|
|
/*
|
|
* Do not allow no accounting for OVERCOMMIT_NEVER, even
|
|
* if it's asked for.
|
|
*/
|
|
if ((shmflg & SHM_NORESERVE) &&
|
|
sysctl_overcommit_memory != OVERCOMMIT_NEVER)
|
|
acctflag = 0;
|
|
file = shmem_file_setup(name, size, acctflag);
|
|
}
|
|
error = PTR_ERR(file);
|
|
if (IS_ERR(file))
|
|
goto no_file;
|
|
|
|
id = shm_addid(ns, shp);
|
|
if (id < 0) {
|
|
error = id;
|
|
goto no_id;
|
|
}
|
|
|
|
shp->shm_cprid = task_tgid_vnr(current);
|
|
shp->shm_lprid = 0;
|
|
shp->shm_atim = shp->shm_dtim = 0;
|
|
shp->shm_ctim = get_seconds();
|
|
shp->shm_segsz = size;
|
|
shp->shm_nattch = 0;
|
|
shp->shm_perm.id = shm_buildid(id, shp->shm_perm.seq);
|
|
shp->shm_file = file;
|
|
/*
|
|
* shmid gets reported as "inode#" in /proc/pid/maps.
|
|
* proc-ps tools use this. Changing this will break them.
|
|
*/
|
|
file->f_dentry->d_inode->i_ino = shp->shm_perm.id;
|
|
|
|
ns->shm_tot += numpages;
|
|
error = shp->shm_perm.id;
|
|
shm_unlock(shp);
|
|
return error;
|
|
|
|
no_id:
|
|
fput(file);
|
|
no_file:
|
|
security_shm_free(shp);
|
|
ipc_rcu_putref(shp);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Called with shm_ids.rw_mutex and ipcp locked.
|
|
*/
|
|
static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
|
|
{
|
|
struct shmid_kernel *shp;
|
|
|
|
shp = container_of(ipcp, struct shmid_kernel, shm_perm);
|
|
return security_shm_associate(shp, shmflg);
|
|
}
|
|
|
|
/*
|
|
* Called with shm_ids.rw_mutex and ipcp locked.
|
|
*/
|
|
static inline int shm_more_checks(struct kern_ipc_perm *ipcp,
|
|
struct ipc_params *params)
|
|
{
|
|
struct shmid_kernel *shp;
|
|
|
|
shp = container_of(ipcp, struct shmid_kernel, shm_perm);
|
|
if (shp->shm_segsz < params->u.size)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
asmlinkage long sys_shmget (key_t key, size_t size, int shmflg)
|
|
{
|
|
struct ipc_namespace *ns;
|
|
struct ipc_ops shm_ops;
|
|
struct ipc_params shm_params;
|
|
|
|
ns = current->nsproxy->ipc_ns;
|
|
|
|
shm_ops.getnew = newseg;
|
|
shm_ops.associate = shm_security;
|
|
shm_ops.more_checks = shm_more_checks;
|
|
|
|
shm_params.key = key;
|
|
shm_params.flg = shmflg;
|
|
shm_params.u.size = size;
|
|
|
|
return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params);
|
|
}
|
|
|
|
static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version)
|
|
{
|
|
switch(version) {
|
|
case IPC_64:
|
|
return copy_to_user(buf, in, sizeof(*in));
|
|
case IPC_OLD:
|
|
{
|
|
struct shmid_ds out;
|
|
|
|
ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm);
|
|
out.shm_segsz = in->shm_segsz;
|
|
out.shm_atime = in->shm_atime;
|
|
out.shm_dtime = in->shm_dtime;
|
|
out.shm_ctime = in->shm_ctime;
|
|
out.shm_cpid = in->shm_cpid;
|
|
out.shm_lpid = in->shm_lpid;
|
|
out.shm_nattch = in->shm_nattch;
|
|
|
|
return copy_to_user(buf, &out, sizeof(out));
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
struct shm_setbuf {
|
|
uid_t uid;
|
|
gid_t gid;
|
|
mode_t mode;
|
|
};
|
|
|
|
static inline unsigned long copy_shmid_from_user(struct shm_setbuf *out, void __user *buf, int version)
|
|
{
|
|
switch(version) {
|
|
case IPC_64:
|
|
{
|
|
struct shmid64_ds tbuf;
|
|
|
|
if (copy_from_user(&tbuf, buf, sizeof(tbuf)))
|
|
return -EFAULT;
|
|
|
|
out->uid = tbuf.shm_perm.uid;
|
|
out->gid = tbuf.shm_perm.gid;
|
|
out->mode = tbuf.shm_perm.mode;
|
|
|
|
return 0;
|
|
}
|
|
case IPC_OLD:
|
|
{
|
|
struct shmid_ds tbuf_old;
|
|
|
|
if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
|
|
return -EFAULT;
|
|
|
|
out->uid = tbuf_old.shm_perm.uid;
|
|
out->gid = tbuf_old.shm_perm.gid;
|
|
out->mode = tbuf_old.shm_perm.mode;
|
|
|
|
return 0;
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version)
|
|
{
|
|
switch(version) {
|
|
case IPC_64:
|
|
return copy_to_user(buf, in, sizeof(*in));
|
|
case IPC_OLD:
|
|
{
|
|
struct shminfo out;
|
|
|
|
if(in->shmmax > INT_MAX)
|
|
out.shmmax = INT_MAX;
|
|
else
|
|
out.shmmax = (int)in->shmmax;
|
|
|
|
out.shmmin = in->shmmin;
|
|
out.shmmni = in->shmmni;
|
|
out.shmseg = in->shmseg;
|
|
out.shmall = in->shmall;
|
|
|
|
return copy_to_user(buf, &out, sizeof(out));
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Called with shm_ids.rw_mutex held as a reader
|
|
*/
|
|
static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
|
|
unsigned long *swp)
|
|
{
|
|
int next_id;
|
|
int total, in_use;
|
|
|
|
*rss = 0;
|
|
*swp = 0;
|
|
|
|
in_use = shm_ids(ns).in_use;
|
|
|
|
for (total = 0, next_id = 0; total < in_use; next_id++) {
|
|
struct shmid_kernel *shp;
|
|
struct inode *inode;
|
|
|
|
shp = idr_find(&shm_ids(ns).ipcs_idr, next_id);
|
|
if (shp == NULL)
|
|
continue;
|
|
|
|
inode = shp->shm_file->f_path.dentry->d_inode;
|
|
|
|
if (is_file_hugepages(shp->shm_file)) {
|
|
struct address_space *mapping = inode->i_mapping;
|
|
*rss += (HPAGE_SIZE/PAGE_SIZE)*mapping->nrpages;
|
|
} else {
|
|
struct shmem_inode_info *info = SHMEM_I(inode);
|
|
spin_lock(&info->lock);
|
|
*rss += inode->i_mapping->nrpages;
|
|
*swp += info->swapped;
|
|
spin_unlock(&info->lock);
|
|
}
|
|
|
|
total++;
|
|
}
|
|
}
|
|
|
|
asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
|
|
{
|
|
struct shm_setbuf setbuf;
|
|
struct shmid_kernel *shp;
|
|
int err, version;
|
|
struct ipc_namespace *ns;
|
|
|
|
if (cmd < 0 || shmid < 0) {
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
version = ipc_parse_version(&cmd);
|
|
ns = current->nsproxy->ipc_ns;
|
|
|
|
switch (cmd) { /* replace with proc interface ? */
|
|
case IPC_INFO:
|
|
{
|
|
struct shminfo64 shminfo;
|
|
|
|
err = security_shm_shmctl(NULL, cmd);
|
|
if (err)
|
|
return err;
|
|
|
|
memset(&shminfo,0,sizeof(shminfo));
|
|
shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni;
|
|
shminfo.shmmax = ns->shm_ctlmax;
|
|
shminfo.shmall = ns->shm_ctlall;
|
|
|
|
shminfo.shmmin = SHMMIN;
|
|
if(copy_shminfo_to_user (buf, &shminfo, version))
|
|
return -EFAULT;
|
|
|
|
down_read(&shm_ids(ns).rw_mutex);
|
|
err = ipc_get_maxid(&shm_ids(ns));
|
|
up_read(&shm_ids(ns).rw_mutex);
|
|
|
|
if(err<0)
|
|
err = 0;
|
|
goto out;
|
|
}
|
|
case SHM_INFO:
|
|
{
|
|
struct shm_info shm_info;
|
|
|
|
err = security_shm_shmctl(NULL, cmd);
|
|
if (err)
|
|
return err;
|
|
|
|
memset(&shm_info,0,sizeof(shm_info));
|
|
down_read(&shm_ids(ns).rw_mutex);
|
|
shm_info.used_ids = shm_ids(ns).in_use;
|
|
shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp);
|
|
shm_info.shm_tot = ns->shm_tot;
|
|
shm_info.swap_attempts = 0;
|
|
shm_info.swap_successes = 0;
|
|
err = ipc_get_maxid(&shm_ids(ns));
|
|
up_read(&shm_ids(ns).rw_mutex);
|
|
if(copy_to_user (buf, &shm_info, sizeof(shm_info))) {
|
|
err = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
err = err < 0 ? 0 : err;
|
|
goto out;
|
|
}
|
|
case SHM_STAT:
|
|
case IPC_STAT:
|
|
{
|
|
struct shmid64_ds tbuf;
|
|
int result;
|
|
|
|
if (!buf) {
|
|
err = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
if (cmd == SHM_STAT) {
|
|
shp = shm_lock(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out;
|
|
}
|
|
result = shp->shm_perm.id;
|
|
} else {
|
|
shp = shm_lock_check(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out;
|
|
}
|
|
result = 0;
|
|
}
|
|
err=-EACCES;
|
|
if (ipcperms (&shp->shm_perm, S_IRUGO))
|
|
goto out_unlock;
|
|
err = security_shm_shmctl(shp, cmd);
|
|
if (err)
|
|
goto out_unlock;
|
|
memset(&tbuf, 0, sizeof(tbuf));
|
|
kernel_to_ipc64_perm(&shp->shm_perm, &tbuf.shm_perm);
|
|
tbuf.shm_segsz = shp->shm_segsz;
|
|
tbuf.shm_atime = shp->shm_atim;
|
|
tbuf.shm_dtime = shp->shm_dtim;
|
|
tbuf.shm_ctime = shp->shm_ctim;
|
|
tbuf.shm_cpid = shp->shm_cprid;
|
|
tbuf.shm_lpid = shp->shm_lprid;
|
|
tbuf.shm_nattch = shp->shm_nattch;
|
|
shm_unlock(shp);
|
|
if(copy_shmid_to_user (buf, &tbuf, version))
|
|
err = -EFAULT;
|
|
else
|
|
err = result;
|
|
goto out;
|
|
}
|
|
case SHM_LOCK:
|
|
case SHM_UNLOCK:
|
|
{
|
|
shp = shm_lock_check(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out;
|
|
}
|
|
|
|
err = audit_ipc_obj(&(shp->shm_perm));
|
|
if (err)
|
|
goto out_unlock;
|
|
|
|
if (!capable(CAP_IPC_LOCK)) {
|
|
err = -EPERM;
|
|
if (current->euid != shp->shm_perm.uid &&
|
|
current->euid != shp->shm_perm.cuid)
|
|
goto out_unlock;
|
|
if (cmd == SHM_LOCK &&
|
|
!current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur)
|
|
goto out_unlock;
|
|
}
|
|
|
|
err = security_shm_shmctl(shp, cmd);
|
|
if (err)
|
|
goto out_unlock;
|
|
|
|
if(cmd==SHM_LOCK) {
|
|
struct user_struct * user = current->user;
|
|
if (!is_file_hugepages(shp->shm_file)) {
|
|
err = shmem_lock(shp->shm_file, 1, user);
|
|
if (!err && !(shp->shm_perm.mode & SHM_LOCKED)){
|
|
shp->shm_perm.mode |= SHM_LOCKED;
|
|
shp->mlock_user = user;
|
|
}
|
|
}
|
|
} else if (!is_file_hugepages(shp->shm_file)) {
|
|
shmem_lock(shp->shm_file, 0, shp->mlock_user);
|
|
shp->shm_perm.mode &= ~SHM_LOCKED;
|
|
shp->mlock_user = NULL;
|
|
}
|
|
shm_unlock(shp);
|
|
goto out;
|
|
}
|
|
case IPC_RMID:
|
|
{
|
|
/*
|
|
* We cannot simply remove the file. The SVID states
|
|
* that the block remains until the last person
|
|
* detaches from it, then is deleted. A shmat() on
|
|
* an RMID segment is legal in older Linux and if
|
|
* we change it apps break...
|
|
*
|
|
* Instead we set a destroyed flag, and then blow
|
|
* the name away when the usage hits zero.
|
|
*/
|
|
down_write(&shm_ids(ns).rw_mutex);
|
|
shp = shm_lock_check_down(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out_up;
|
|
}
|
|
|
|
err = audit_ipc_obj(&(shp->shm_perm));
|
|
if (err)
|
|
goto out_unlock_up;
|
|
|
|
if (current->euid != shp->shm_perm.uid &&
|
|
current->euid != shp->shm_perm.cuid &&
|
|
!capable(CAP_SYS_ADMIN)) {
|
|
err=-EPERM;
|
|
goto out_unlock_up;
|
|
}
|
|
|
|
err = security_shm_shmctl(shp, cmd);
|
|
if (err)
|
|
goto out_unlock_up;
|
|
|
|
do_shm_rmid(ns, shp);
|
|
up_write(&shm_ids(ns).rw_mutex);
|
|
goto out;
|
|
}
|
|
|
|
case IPC_SET:
|
|
{
|
|
if (!buf) {
|
|
err = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
if (copy_shmid_from_user (&setbuf, buf, version)) {
|
|
err = -EFAULT;
|
|
goto out;
|
|
}
|
|
down_write(&shm_ids(ns).rw_mutex);
|
|
shp = shm_lock_check_down(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out_up;
|
|
}
|
|
err = audit_ipc_obj(&(shp->shm_perm));
|
|
if (err)
|
|
goto out_unlock_up;
|
|
err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode);
|
|
if (err)
|
|
goto out_unlock_up;
|
|
err=-EPERM;
|
|
if (current->euid != shp->shm_perm.uid &&
|
|
current->euid != shp->shm_perm.cuid &&
|
|
!capable(CAP_SYS_ADMIN)) {
|
|
goto out_unlock_up;
|
|
}
|
|
|
|
err = security_shm_shmctl(shp, cmd);
|
|
if (err)
|
|
goto out_unlock_up;
|
|
|
|
shp->shm_perm.uid = setbuf.uid;
|
|
shp->shm_perm.gid = setbuf.gid;
|
|
shp->shm_perm.mode = (shp->shm_perm.mode & ~S_IRWXUGO)
|
|
| (setbuf.mode & S_IRWXUGO);
|
|
shp->shm_ctim = get_seconds();
|
|
break;
|
|
}
|
|
|
|
default:
|
|
err = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
err = 0;
|
|
out_unlock_up:
|
|
shm_unlock(shp);
|
|
out_up:
|
|
up_write(&shm_ids(ns).rw_mutex);
|
|
goto out;
|
|
out_unlock:
|
|
shm_unlock(shp);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists.
|
|
*
|
|
* NOTE! Despite the name, this is NOT a direct system call entrypoint. The
|
|
* "raddr" thing points to kernel space, and there has to be a wrapper around
|
|
* this.
|
|
*/
|
|
long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
|
|
{
|
|
struct shmid_kernel *shp;
|
|
unsigned long addr;
|
|
unsigned long size;
|
|
struct file * file;
|
|
int err;
|
|
unsigned long flags;
|
|
unsigned long prot;
|
|
int acc_mode;
|
|
unsigned long user_addr;
|
|
struct ipc_namespace *ns;
|
|
struct shm_file_data *sfd;
|
|
struct path path;
|
|
mode_t f_mode;
|
|
|
|
err = -EINVAL;
|
|
if (shmid < 0)
|
|
goto out;
|
|
else if ((addr = (ulong)shmaddr)) {
|
|
if (addr & (SHMLBA-1)) {
|
|
if (shmflg & SHM_RND)
|
|
addr &= ~(SHMLBA-1); /* round down */
|
|
else
|
|
#ifndef __ARCH_FORCE_SHMLBA
|
|
if (addr & ~PAGE_MASK)
|
|
#endif
|
|
goto out;
|
|
}
|
|
flags = MAP_SHARED | MAP_FIXED;
|
|
} else {
|
|
if ((shmflg & SHM_REMAP))
|
|
goto out;
|
|
|
|
flags = MAP_SHARED;
|
|
}
|
|
|
|
if (shmflg & SHM_RDONLY) {
|
|
prot = PROT_READ;
|
|
acc_mode = S_IRUGO;
|
|
f_mode = FMODE_READ;
|
|
} else {
|
|
prot = PROT_READ | PROT_WRITE;
|
|
acc_mode = S_IRUGO | S_IWUGO;
|
|
f_mode = FMODE_READ | FMODE_WRITE;
|
|
}
|
|
if (shmflg & SHM_EXEC) {
|
|
prot |= PROT_EXEC;
|
|
acc_mode |= S_IXUGO;
|
|
}
|
|
|
|
/*
|
|
* We cannot rely on the fs check since SYSV IPC does have an
|
|
* additional creator id...
|
|
*/
|
|
ns = current->nsproxy->ipc_ns;
|
|
shp = shm_lock_check(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out;
|
|
}
|
|
|
|
err = -EACCES;
|
|
if (ipcperms(&shp->shm_perm, acc_mode))
|
|
goto out_unlock;
|
|
|
|
err = security_shm_shmat(shp, shmaddr, shmflg);
|
|
if (err)
|
|
goto out_unlock;
|
|
|
|
path.dentry = dget(shp->shm_file->f_path.dentry);
|
|
path.mnt = shp->shm_file->f_path.mnt;
|
|
shp->shm_nattch++;
|
|
size = i_size_read(path.dentry->d_inode);
|
|
shm_unlock(shp);
|
|
|
|
err = -ENOMEM;
|
|
sfd = kzalloc(sizeof(*sfd), GFP_KERNEL);
|
|
if (!sfd)
|
|
goto out_put_dentry;
|
|
|
|
err = -ENOMEM;
|
|
|
|
file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations);
|
|
if (!file)
|
|
goto out_free;
|
|
|
|
file->private_data = sfd;
|
|
file->f_mapping = shp->shm_file->f_mapping;
|
|
sfd->id = shp->shm_perm.id;
|
|
sfd->ns = get_ipc_ns(ns);
|
|
sfd->file = shp->shm_file;
|
|
sfd->vm_ops = NULL;
|
|
|
|
down_write(¤t->mm->mmap_sem);
|
|
if (addr && !(shmflg & SHM_REMAP)) {
|
|
err = -EINVAL;
|
|
if (find_vma_intersection(current->mm, addr, addr + size))
|
|
goto invalid;
|
|
/*
|
|
* If shm segment goes below stack, make sure there is some
|
|
* space left for the stack to grow (at least 4 pages).
|
|
*/
|
|
if (addr < current->mm->start_stack &&
|
|
addr > current->mm->start_stack - size - PAGE_SIZE * 5)
|
|
goto invalid;
|
|
}
|
|
|
|
user_addr = do_mmap (file, addr, size, prot, flags, 0);
|
|
*raddr = user_addr;
|
|
err = 0;
|
|
if (IS_ERR_VALUE(user_addr))
|
|
err = (long)user_addr;
|
|
invalid:
|
|
up_write(¤t->mm->mmap_sem);
|
|
|
|
fput(file);
|
|
|
|
out_nattch:
|
|
down_write(&shm_ids(ns).rw_mutex);
|
|
shp = shm_lock_down(ns, shmid);
|
|
BUG_ON(IS_ERR(shp));
|
|
shp->shm_nattch--;
|
|
if(shp->shm_nattch == 0 &&
|
|
shp->shm_perm.mode & SHM_DEST)
|
|
shm_destroy(ns, shp);
|
|
else
|
|
shm_unlock(shp);
|
|
up_write(&shm_ids(ns).rw_mutex);
|
|
|
|
out:
|
|
return err;
|
|
|
|
out_unlock:
|
|
shm_unlock(shp);
|
|
goto out;
|
|
|
|
out_free:
|
|
kfree(sfd);
|
|
out_put_dentry:
|
|
dput(path.dentry);
|
|
goto out_nattch;
|
|
}
|
|
|
|
asmlinkage long sys_shmat(int shmid, char __user *shmaddr, int shmflg)
|
|
{
|
|
unsigned long ret;
|
|
long err;
|
|
|
|
err = do_shmat(shmid, shmaddr, shmflg, &ret);
|
|
if (err)
|
|
return err;
|
|
force_successful_syscall_return();
|
|
return (long)ret;
|
|
}
|
|
|
|
/*
|
|
* detach and kill segment if marked destroyed.
|
|
* The work is done in shm_close.
|
|
*/
|
|
asmlinkage long sys_shmdt(char __user *shmaddr)
|
|
{
|
|
struct mm_struct *mm = current->mm;
|
|
struct vm_area_struct *vma, *next;
|
|
unsigned long addr = (unsigned long)shmaddr;
|
|
loff_t size = 0;
|
|
int retval = -EINVAL;
|
|
|
|
if (addr & ~PAGE_MASK)
|
|
return retval;
|
|
|
|
down_write(&mm->mmap_sem);
|
|
|
|
/*
|
|
* This function tries to be smart and unmap shm segments that
|
|
* were modified by partial mlock or munmap calls:
|
|
* - It first determines the size of the shm segment that should be
|
|
* unmapped: It searches for a vma that is backed by shm and that
|
|
* started at address shmaddr. It records it's size and then unmaps
|
|
* it.
|
|
* - Then it unmaps all shm vmas that started at shmaddr and that
|
|
* are within the initially determined size.
|
|
* Errors from do_munmap are ignored: the function only fails if
|
|
* it's called with invalid parameters or if it's called to unmap
|
|
* a part of a vma. Both calls in this function are for full vmas,
|
|
* the parameters are directly copied from the vma itself and always
|
|
* valid - therefore do_munmap cannot fail. (famous last words?)
|
|
*/
|
|
/*
|
|
* If it had been mremap()'d, the starting address would not
|
|
* match the usual checks anyway. So assume all vma's are
|
|
* above the starting address given.
|
|
*/
|
|
vma = find_vma(mm, addr);
|
|
|
|
while (vma) {
|
|
next = vma->vm_next;
|
|
|
|
/*
|
|
* Check if the starting address would match, i.e. it's
|
|
* a fragment created by mprotect() and/or munmap(), or it
|
|
* otherwise it starts at this address with no hassles.
|
|
*/
|
|
if ((vma->vm_ops == &shm_vm_ops) &&
|
|
(vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) {
|
|
|
|
|
|
size = vma->vm_file->f_path.dentry->d_inode->i_size;
|
|
do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
|
|
/*
|
|
* We discovered the size of the shm segment, so
|
|
* break out of here and fall through to the next
|
|
* loop that uses the size information to stop
|
|
* searching for matching vma's.
|
|
*/
|
|
retval = 0;
|
|
vma = next;
|
|
break;
|
|
}
|
|
vma = next;
|
|
}
|
|
|
|
/*
|
|
* We need look no further than the maximum address a fragment
|
|
* could possibly have landed at. Also cast things to loff_t to
|
|
* prevent overflows and make comparisions vs. equal-width types.
|
|
*/
|
|
size = PAGE_ALIGN(size);
|
|
while (vma && (loff_t)(vma->vm_end - addr) <= size) {
|
|
next = vma->vm_next;
|
|
|
|
/* finding a matching vma now does not alter retval */
|
|
if ((vma->vm_ops == &shm_vm_ops) &&
|
|
(vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff)
|
|
|
|
do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
|
|
vma = next;
|
|
}
|
|
|
|
up_write(&mm->mmap_sem);
|
|
return retval;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
|
|
{
|
|
struct shmid_kernel *shp = it;
|
|
char *format;
|
|
|
|
#define SMALL_STRING "%10d %10d %4o %10u %5u %5u %5d %5u %5u %5u %5u %10lu %10lu %10lu\n"
|
|
#define BIG_STRING "%10d %10d %4o %21u %5u %5u %5d %5u %5u %5u %5u %10lu %10lu %10lu\n"
|
|
|
|
if (sizeof(size_t) <= sizeof(int))
|
|
format = SMALL_STRING;
|
|
else
|
|
format = BIG_STRING;
|
|
return seq_printf(s, format,
|
|
shp->shm_perm.key,
|
|
shp->shm_perm.id,
|
|
shp->shm_perm.mode,
|
|
shp->shm_segsz,
|
|
shp->shm_cprid,
|
|
shp->shm_lprid,
|
|
shp->shm_nattch,
|
|
shp->shm_perm.uid,
|
|
shp->shm_perm.gid,
|
|
shp->shm_perm.cuid,
|
|
shp->shm_perm.cgid,
|
|
shp->shm_atim,
|
|
shp->shm_dtim,
|
|
shp->shm_ctim);
|
|
}
|
|
#endif
|