3 * Copyright (C) 1992 Krishna Balasubramanian
5 * Sep 1997 - Call suser() last after "normal" permission checks so we
6 * get BSD style process accounting right.
7 * Occurs in several places in the IPC code.
8 * Chris Evans, <chris@ferret.lmh.ox.ac.uk>
9 * Nov 1999 - ipc helper functions, unified SMP locking
10 * Manfred Spraul <manfred@colorfullife.com>
11 * Oct 2002 - One lock per IPC id. RCU ipc_free for lock-free grow_ary().
12 * Mingming Cao <cmm@us.ibm.com>
13 * Mar 2006 - support for audit of ipc object properties
14 * Dustin Kirkland <dustin.kirkland@us.ibm.com>
15 * Jun 2006 - namespaces ssupport
17 * Pavel Emelianov <xemul@openvz.org>
21 #include <linux/shm.h>
22 #include <linux/init.h>
23 #include <linux/msg.h>
24 #include <linux/vmalloc.h>
25 #include <linux/slab.h>
26 #include <linux/notifier.h>
27 #include <linux/capability.h>
28 #include <linux/highuid.h>
29 #include <linux/security.h>
30 #include <linux/rcupdate.h>
31 #include <linux/workqueue.h>
32 #include <linux/seq_file.h>
33 #include <linux/proc_fs.h>
34 #include <linux/audit.h>
35 #include <linux/nsproxy.h>
36 #include <linux/rwsem.h>
37 #include <linux/memory.h>
38 #include <linux/ipc_namespace.h>
40 #include <asm/unistd.h>
44 struct ipc_proc_iface {
48 int (*show)(struct seq_file *, void *);
51 static void ipc_memory_notifier(struct work_struct *work)
53 ipcns_notify(IPCNS_MEMCHANGED);
56 static int ipc_memory_callback(struct notifier_block *self,
57 unsigned long action, void *arg)
59 static DECLARE_WORK(ipc_memory_wq, ipc_memory_notifier);
62 case MEM_ONLINE: /* memory successfully brought online */
63 case MEM_OFFLINE: /* or offline: it's time to recompute msgmni */
65 * This is done by invoking the ipcns notifier chain with the
66 * IPC_MEMCHANGED event.
67 * In order not to keep the lock on the hotplug memory chain
68 * for too long, queue a work item that will, when waken up,
69 * activate the ipcns notification chain.
70 * No need to keep several ipc work items on the queue.
72 if (!work_pending(&ipc_memory_wq))
73 schedule_work(&ipc_memory_wq);
75 case MEM_GOING_ONLINE:
76 case MEM_GOING_OFFLINE:
77 case MEM_CANCEL_ONLINE:
78 case MEM_CANCEL_OFFLINE:
86 static struct notifier_block ipc_memory_nb = {
87 .notifier_call = ipc_memory_callback,
88 .priority = IPC_CALLBACK_PRI,
92 * ipc_init - initialise IPC subsystem
94 * The various system5 IPC resources (semaphores, messages and shared
95 * memory) are initialised
96 * A callback routine is registered into the memory hotplug notifier
97 * chain: since msgmni scales to lowmem this callback routine will be
98 * called upon successful memory add / remove to recompute msmgni.
101 static int __init ipc_init(void)
106 register_hotmemory_notifier(&ipc_memory_nb);
107 register_ipcns_notifier(&init_ipc_ns);
110 __initcall(ipc_init);
113 * ipc_init_ids - initialise IPC identifiers
114 * @ids: Identifier set
116 * Set up the sequence range to use for the ipc identifier range (limited
117 * below IPCMNI) then initialise the ids idr.
120 void ipc_init_ids(struct ipc_ids *ids)
122 init_rwsem(&ids->rw_mutex);
128 int seq_limit = INT_MAX/SEQ_MULTIPLIER;
129 if (seq_limit > USHRT_MAX)
130 ids->seq_max = USHRT_MAX;
132 ids->seq_max = seq_limit;
135 idr_init(&ids->ipcs_idr);
138 #ifdef CONFIG_PROC_FS
139 static const struct file_operations sysvipc_proc_fops;
141 * ipc_init_proc_interface - Create a proc interface for sysipc types using a seq_file interface.
142 * @path: Path in procfs
143 * @header: Banner to be printed at the beginning of the file.
144 * @ids: ipc id table to iterate.
145 * @show: show routine.
147 void __init ipc_init_proc_interface(const char *path, const char *header,
148 int ids, int (*show)(struct seq_file *, void *))
150 struct proc_dir_entry *pde;
151 struct ipc_proc_iface *iface;
153 iface = kmalloc(sizeof(*iface), GFP_KERNEL);
157 iface->header = header;
161 pde = proc_create_data(path,
162 S_IRUGO, /* world readable */
163 NULL, /* parent dir */
173 * ipc_findkey - find a key in an ipc identifier set
174 * @ids: Identifier set
175 * @key: The key to find
177 * Requires ipc_ids.rw_mutex locked.
178 * Returns the LOCKED pointer to the ipc structure if found or NULL
180 * If key is found ipc points to the owning ipc structure
183 static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key)
185 struct kern_ipc_perm *ipc;
189 for (total = 0, next_id = 0; total < ids->in_use; next_id++) {
190 ipc = idr_find(&ids->ipcs_idr, next_id);
195 if (ipc->key != key) {
200 ipc_lock_by_ptr(ipc);
208 * ipc_get_maxid - get the last assigned id
209 * @ids: IPC identifier set
211 * Called with ipc_ids.rw_mutex held.
214 int ipc_get_maxid(struct ipc_ids *ids)
216 struct kern_ipc_perm *ipc;
220 if (ids->in_use == 0)
223 if (ids->in_use == IPCMNI)
226 /* Look for the last assigned id */
228 for (id = 0; id < IPCMNI && total < ids->in_use; id++) {
229 ipc = idr_find(&ids->ipcs_idr, id);
239 * ipc_addid - add an IPC identifier
240 * @ids: IPC identifier set
241 * @new: new IPC permission set
242 * @size: limit for the number of used ids
244 * Add an entry 'new' to the IPC ids idr. The permissions object is
245 * initialised and the first free entry is set up and the id assigned
246 * is returned. The 'new' entry is returned in a locked state on success.
247 * On failure the entry is not locked and a negative err-code is returned.
249 * Called with ipc_ids.rw_mutex held as a writer.
252 int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
257 int next_id = ids->next_id;
262 if (ids->in_use >= size)
265 idr_preload(GFP_KERNEL);
267 spin_lock_init(&new->lock);
270 spin_lock(&new->lock);
272 id = idr_alloc(&ids->ipcs_idr, new,
273 (next_id < 0) ? 0 : ipcid_to_idx(next_id), 0,
277 spin_unlock(&new->lock);
284 current_euid_egid(&euid, &egid);
285 new->cuid = new->uid = euid;
286 new->gid = new->cgid = egid;
289 new->seq = ids->seq++;
290 if (ids->seq > ids->seq_max)
293 new->seq = ipcid_to_seqx(next_id);
297 new->id = ipc_buildid(id, new->seq);
302 * ipcget_new - create a new ipc object
304 * @ids: IPC identifer set
305 * @ops: the actual creation routine to call
306 * @params: its parameters
308 * This routine is called by sys_msgget, sys_semget() and sys_shmget()
309 * when the key is IPC_PRIVATE.
311 static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
312 struct ipc_ops *ops, struct ipc_params *params)
316 down_write(&ids->rw_mutex);
317 err = ops->getnew(ns, params);
318 up_write(&ids->rw_mutex);
323 * ipc_check_perms - check security and permissions for an IPC
325 * @ipcp: ipc permission set
326 * @ops: the actual security routine to call
327 * @params: its parameters
329 * This routine is called by sys_msgget(), sys_semget() and sys_shmget()
330 * when the key is not IPC_PRIVATE and that key already exists in the
333 * On success, the IPC id is returned.
335 * It is called with ipc_ids.rw_mutex and ipcp->lock held.
337 static int ipc_check_perms(struct ipc_namespace *ns,
338 struct kern_ipc_perm *ipcp,
340 struct ipc_params *params)
344 if (ipcperms(ns, ipcp, params->flg))
347 err = ops->associate(ipcp, params->flg);
356 * ipcget_public - get an ipc object or create a new one
358 * @ids: IPC identifer set
359 * @ops: the actual creation routine to call
360 * @params: its parameters
362 * This routine is called by sys_msgget, sys_semget() and sys_shmget()
363 * when the key is not IPC_PRIVATE.
364 * It adds a new entry if the key is not found and does some permission
365 * / security checkings if the key is found.
367 * On success, the ipc id is returned.
369 static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
370 struct ipc_ops *ops, struct ipc_params *params)
372 struct kern_ipc_perm *ipcp;
373 int flg = params->flg;
377 * Take the lock as a writer since we are potentially going to add
378 * a new entry + read locks are not "upgradable"
380 down_write(&ids->rw_mutex);
381 ipcp = ipc_findkey(ids, params->key);
384 if (!(flg & IPC_CREAT))
387 err = ops->getnew(ns, params);
389 /* ipc object has been locked by ipc_findkey() */
391 if (flg & IPC_CREAT && flg & IPC_EXCL)
395 if (ops->more_checks)
396 err = ops->more_checks(ipcp, params);
399 * ipc_check_perms returns the IPC id on
402 err = ipc_check_perms(ns, ipcp, ops, params);
406 up_write(&ids->rw_mutex);
413 * ipc_rmid - remove an IPC identifier
414 * @ids: IPC identifier set
415 * @ipcp: ipc perm structure containing the identifier to remove
417 * ipc_ids.rw_mutex (as a writer) and the spinlock for this ID are held
418 * before this function is called, and remain locked on the exit.
421 void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)
423 int lid = ipcid_to_idx(ipcp->id);
425 idr_remove(&ids->ipcs_idr, lid);
435 * ipc_alloc - allocate ipc space
436 * @size: size desired
438 * Allocate memory from the appropriate pools and return a pointer to it.
439 * NULL is returned if the allocation fails
442 void* ipc_alloc(int size)
448 out = kmalloc(size, GFP_KERNEL);
453 * ipc_free - free ipc space
454 * @ptr: pointer returned by ipc_alloc
455 * @size: size of block
457 * Free a block created with ipc_alloc(). The caller must know the size
458 * used in the allocation call.
461 void ipc_free(void* ptr, int size)
471 * There are three headers that are prepended to the actual allocation:
472 * - during use: ipc_rcu_hdr.
473 * - during the rcu grace period: ipc_rcu_grace.
474 * - [only if vmalloc]: ipc_rcu_sched.
475 * Their lifetime doesn't overlap, thus the headers share the same memory.
476 * Unlike a normal union, they are right-aligned, thus some container_of
477 * forward/backward casting is necessary:
490 /* "void *" makes sure alignment of following data is sane. */
496 struct work_struct work;
497 /* "void *" makes sure alignment of following data is sane. */
501 #define HDRLEN_KMALLOC (sizeof(struct ipc_rcu_grace) > sizeof(struct ipc_rcu_hdr) ? \
502 sizeof(struct ipc_rcu_grace) : sizeof(struct ipc_rcu_hdr))
503 #define HDRLEN_VMALLOC (sizeof(struct ipc_rcu_sched) > HDRLEN_KMALLOC ? \
504 sizeof(struct ipc_rcu_sched) : HDRLEN_KMALLOC)
506 static inline int rcu_use_vmalloc(int size)
508 /* Too big for a single page? */
509 if (HDRLEN_KMALLOC + size > PAGE_SIZE)
515 * ipc_rcu_alloc - allocate ipc and rcu space
516 * @size: size desired
518 * Allocate memory for the rcu header structure + the object.
519 * Returns the pointer to the object.
520 * NULL is returned if the allocation fails.
523 void* ipc_rcu_alloc(int size)
527 * We prepend the allocation with the rcu struct, and
528 * workqueue if necessary (for vmalloc).
530 if (rcu_use_vmalloc(size)) {
531 out = vmalloc(HDRLEN_VMALLOC + size);
533 out += HDRLEN_VMALLOC;
534 container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1;
535 container_of(out, struct ipc_rcu_hdr, data)->refcount = 1;
538 out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL);
540 out += HDRLEN_KMALLOC;
541 container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0;
542 container_of(out, struct ipc_rcu_hdr, data)->refcount = 1;
549 void ipc_rcu_getref(void *ptr)
551 container_of(ptr, struct ipc_rcu_hdr, data)->refcount++;
554 static void ipc_do_vfree(struct work_struct *work)
556 vfree(container_of(work, struct ipc_rcu_sched, work));
560 * ipc_schedule_free - free ipc + rcu space
561 * @head: RCU callback structure for queued work
563 * Since RCU callback function is called in bh,
564 * we need to defer the vfree to schedule_work().
566 static void ipc_schedule_free(struct rcu_head *head)
568 struct ipc_rcu_grace *grace;
569 struct ipc_rcu_sched *sched;
571 grace = container_of(head, struct ipc_rcu_grace, rcu);
572 sched = container_of(&(grace->data[0]), struct ipc_rcu_sched,
575 INIT_WORK(&sched->work, ipc_do_vfree);
576 schedule_work(&sched->work);
579 void ipc_rcu_putref(void *ptr)
581 if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0)
584 if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
585 call_rcu(&container_of(ptr, struct ipc_rcu_grace, data)->rcu,
588 kfree_rcu(container_of(ptr, struct ipc_rcu_grace, data), rcu);
593 * ipcperms - check IPC permissions
595 * @ipcp: IPC permission set
596 * @flag: desired permission set.
598 * Check user, group, other permissions for access
599 * to ipc resources. return 0 if allowed
601 * @flag will most probably be 0 or S_...UGO from <linux/stat.h>
604 int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flag)
606 kuid_t euid = current_euid();
607 int requested_mode, granted_mode;
610 requested_mode = (flag >> 6) | (flag >> 3) | flag;
611 granted_mode = ipcp->mode;
612 if (uid_eq(euid, ipcp->cuid) ||
613 uid_eq(euid, ipcp->uid))
615 else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid))
617 /* is there some bit set in requested_mode but not in granted_mode? */
618 if ((requested_mode & ~granted_mode & 0007) &&
619 !ns_capable(ns->user_ns, CAP_IPC_OWNER))
622 return security_ipc_permission(ipcp, flag);
626 * Functions to convert between the kern_ipc_perm structure and the
627 * old/new ipc_perm structures
631 * kernel_to_ipc64_perm - convert kernel ipc permissions to user
632 * @in: kernel permissions
633 * @out: new style IPC permissions
635 * Turn the kernel object @in into a set of permissions descriptions
636 * for returning to userspace (@out).
640 void kernel_to_ipc64_perm (struct kern_ipc_perm *in, struct ipc64_perm *out)
643 out->uid = from_kuid_munged(current_user_ns(), in->uid);
644 out->gid = from_kgid_munged(current_user_ns(), in->gid);
645 out->cuid = from_kuid_munged(current_user_ns(), in->cuid);
646 out->cgid = from_kgid_munged(current_user_ns(), in->cgid);
647 out->mode = in->mode;
652 * ipc64_perm_to_ipc_perm - convert new ipc permissions to old
653 * @in: new style IPC permissions
654 * @out: old style IPC permissions
656 * Turn the new style permissions object @in into a compatibility
657 * object and store it into the @out pointer.
660 void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out)
663 SET_UID(out->uid, in->uid);
664 SET_GID(out->gid, in->gid);
665 SET_UID(out->cuid, in->cuid);
666 SET_GID(out->cgid, in->cgid);
667 out->mode = in->mode;
673 * @ids: ipc identifier set
674 * @id: ipc id to look for
676 * Look for an id in the ipc ids idr and return associated ipc object.
678 * Call inside the RCU critical section.
679 * The ipc object is *not* locked on exit.
681 struct kern_ipc_perm *ipc_obtain_object(struct ipc_ids *ids, int id)
683 struct kern_ipc_perm *out;
684 int lid = ipcid_to_idx(id);
686 out = idr_find(&ids->ipcs_idr, lid);
688 return ERR_PTR(-EINVAL);
694 * ipc_lock - Lock an ipc structure without rw_mutex held
695 * @ids: IPC identifier set
696 * @id: ipc id to look for
698 * Look for an id in the ipc ids idr and lock the associated ipc object.
700 * The ipc object is locked on successful exit.
702 struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
704 struct kern_ipc_perm *out;
707 out = ipc_obtain_object(ids, id);
711 spin_lock(&out->lock);
713 /* ipc_rmid() may have already freed the ID while ipc_lock
714 * was spinning: here verify that the structure is still valid
719 spin_unlock(&out->lock);
720 out = ERR_PTR(-EINVAL);
727 * ipc_obtain_object_check
728 * @ids: ipc identifier set
729 * @id: ipc id to look for
731 * Similar to ipc_obtain_object() but also checks
732 * the ipc object reference counter.
734 * Call inside the RCU critical section.
735 * The ipc object is *not* locked on exit.
737 struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id)
739 struct kern_ipc_perm *out = ipc_obtain_object(ids, id);
744 if (ipc_checkid(out, id))
745 return ERR_PTR(-EIDRM);
750 struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id)
752 struct kern_ipc_perm *out;
754 out = ipc_lock(ids, id);
758 if (ipc_checkid(out, id)) {
760 return ERR_PTR(-EIDRM);
767 * ipcget - Common sys_*get() code
769 * @ids : IPC identifier set
770 * @ops : operations to be called on ipc object creation, permission checks
772 * @params : the parameters needed by the previous operations.
774 * Common routine called by sys_msgget(), sys_semget() and sys_shmget().
776 int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
777 struct ipc_ops *ops, struct ipc_params *params)
779 if (params->key == IPC_PRIVATE)
780 return ipcget_new(ns, ids, ops, params);
782 return ipcget_public(ns, ids, ops, params);
786 * ipc_update_perm - update the permissions of an IPC.
787 * @in: the permission given as input.
788 * @out: the permission of the ipc to set.
790 int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
792 kuid_t uid = make_kuid(current_user_ns(), in->uid);
793 kgid_t gid = make_kgid(current_user_ns(), in->gid);
794 if (!uid_valid(uid) || !gid_valid(gid))
799 out->mode = (out->mode & ~S_IRWXUGO)
800 | (in->mode & S_IRWXUGO);
806 * ipcctl_pre_down - retrieve an ipc and check permissions for some IPC_XXX cmd
807 * @ns: the ipc namespace
808 * @ids: the table of ids where to look for the ipc
809 * @id: the id of the ipc to retrieve
810 * @cmd: the cmd to check
811 * @perm: the permission to set
812 * @extra_perm: one extra permission parameter used by msq
814 * This function does some common audit and permissions check for some IPC_XXX
815 * cmd and is called from semctl_down, shmctl_down and msgctl_down.
816 * It must be called without any lock held and
817 * - retrieves the ipc with the given id in the given table.
818 * - performs some audit and permission check, depending on the given cmd
819 * - returns the ipc with both ipc and rw_mutex locks held in case of success
820 * or an err-code without any lock held otherwise.
822 struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns,
823 struct ipc_ids *ids, int id, int cmd,
824 struct ipc64_perm *perm, int extra_perm)
826 struct kern_ipc_perm *ipcp;
828 ipcp = ipcctl_pre_down_nolock(ns, ids, id, cmd, perm, extra_perm);
832 spin_lock(&ipcp->lock);
837 struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns,
838 struct ipc_ids *ids, int id, int cmd,
839 struct ipc64_perm *perm, int extra_perm)
843 struct kern_ipc_perm *ipcp;
845 down_write(&ids->rw_mutex);
848 ipcp = ipc_obtain_object_check(ids, id);
856 audit_ipc_set_perm(extra_perm, perm->uid,
857 perm->gid, perm->mode);
859 euid = current_euid();
860 if (uid_eq(euid, ipcp->cuid) || uid_eq(euid, ipcp->uid) ||
861 ns_capable(ns->user_ns, CAP_SYS_ADMIN))
866 * Unsuccessful lookup, unlock and return
867 * the corresponding error.
870 up_write(&ids->rw_mutex);
875 #ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
879 * ipc_parse_version - IPC call version
880 * @cmd: pointer to command
882 * Return IPC_64 for new style IPC and IPC_OLD for old style IPC.
883 * The @cmd value is turned from an encoding command and version into
884 * just the command code.
887 int ipc_parse_version (int *cmd)
897 #endif /* CONFIG_ARCH_WANT_IPC_PARSE_VERSION */
899 #ifdef CONFIG_PROC_FS
900 struct ipc_proc_iter {
901 struct ipc_namespace *ns;
902 struct ipc_proc_iface *iface;
906 * This routine locks the ipc structure found at least at position pos.
908 static struct kern_ipc_perm *sysvipc_find_ipc(struct ipc_ids *ids, loff_t pos,
911 struct kern_ipc_perm *ipc;
915 for (id = 0; id < pos && total < ids->in_use; id++) {
916 ipc = idr_find(&ids->ipcs_idr, id);
921 if (total >= ids->in_use)
924 for ( ; pos < IPCMNI; pos++) {
925 ipc = idr_find(&ids->ipcs_idr, pos);
928 ipc_lock_by_ptr(ipc);
933 /* Out of range - return NULL to terminate iteration */
937 static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos)
939 struct ipc_proc_iter *iter = s->private;
940 struct ipc_proc_iface *iface = iter->iface;
941 struct kern_ipc_perm *ipc = it;
943 /* If we had an ipc id locked before, unlock it */
944 if (ipc && ipc != SEQ_START_TOKEN)
947 return sysvipc_find_ipc(&iter->ns->ids[iface->ids], *pos, pos);
951 * File positions: pos 0 -> header, pos n -> ipc id = n - 1.
952 * SeqFile iterator: iterator value locked ipc pointer or SEQ_TOKEN_START.
954 static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos)
956 struct ipc_proc_iter *iter = s->private;
957 struct ipc_proc_iface *iface = iter->iface;
960 ids = &iter->ns->ids[iface->ids];
963 * Take the lock - this will be released by the corresponding
966 down_read(&ids->rw_mutex);
968 /* pos < 0 is invalid */
972 /* pos == 0 means header */
974 return SEQ_START_TOKEN;
976 /* Find the (pos-1)th ipc */
977 return sysvipc_find_ipc(ids, *pos - 1, pos);
980 static void sysvipc_proc_stop(struct seq_file *s, void *it)
982 struct kern_ipc_perm *ipc = it;
983 struct ipc_proc_iter *iter = s->private;
984 struct ipc_proc_iface *iface = iter->iface;
987 /* If we had a locked structure, release it */
988 if (ipc && ipc != SEQ_START_TOKEN)
991 ids = &iter->ns->ids[iface->ids];
992 /* Release the lock we took in start() */
993 up_read(&ids->rw_mutex);
996 static int sysvipc_proc_show(struct seq_file *s, void *it)
998 struct ipc_proc_iter *iter = s->private;
999 struct ipc_proc_iface *iface = iter->iface;
1001 if (it == SEQ_START_TOKEN)
1002 return seq_puts(s, iface->header);
1004 return iface->show(s, it);
1007 static const struct seq_operations sysvipc_proc_seqops = {
1008 .start = sysvipc_proc_start,
1009 .stop = sysvipc_proc_stop,
1010 .next = sysvipc_proc_next,
1011 .show = sysvipc_proc_show,
1014 static int sysvipc_proc_open(struct inode *inode, struct file *file)
1017 struct seq_file *seq;
1018 struct ipc_proc_iter *iter;
1021 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
1025 ret = seq_open(file, &sysvipc_proc_seqops);
1029 seq = file->private_data;
1030 seq->private = iter;
1032 iter->iface = PDE(inode)->data;
1033 iter->ns = get_ipc_ns(current->nsproxy->ipc_ns);
1041 static int sysvipc_proc_release(struct inode *inode, struct file *file)
1043 struct seq_file *seq = file->private_data;
1044 struct ipc_proc_iter *iter = seq->private;
1045 put_ipc_ns(iter->ns);
1046 return seq_release_private(inode, file);
1049 static const struct file_operations sysvipc_proc_fops = {
1050 .open = sysvipc_proc_open,
1052 .llseek = seq_lseek,
1053 .release = sysvipc_proc_release,
1055 #endif /* CONFIG_PROC_FS */