xref: /linux/ipc/msg.c (revision 889b3317)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/ipc/msg.c
4  * Copyright (C) 1992 Krishna Balasubramanian
5  *
6  * Removed all the remaining kerneld mess
7  * Catch the -EFAULT stuff properly
8  * Use GFP_KERNEL for messages as in 1.2
9  * Fixed up the unchecked user space derefs
10  * Copyright (C) 1998 Alan Cox & Andi Kleen
11  *
12  * /proc/sysvipc/msg support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
13  *
14  * mostly rewritten, threaded and wake-one semantics added
15  * MSGMAX limit removed, sysctl's added
16  * (c) 1999 Manfred Spraul <manfred@colorfullife.com>
17  *
18  * support for audit of ipc object properties and permission changes
19  * Dustin Kirkland <dustin.kirkland@us.ibm.com>
20  *
21  * namespaces support
22  * OpenVZ, SWsoft Inc.
23  * Pavel Emelianov <xemul@openvz.org>
24  */
25 
26 #include <linux/capability.h>
27 #include <linux/msg.h>
28 #include <linux/spinlock.h>
29 #include <linux/init.h>
30 #include <linux/mm.h>
31 #include <linux/proc_fs.h>
32 #include <linux/list.h>
33 #include <linux/security.h>
34 #include <linux/sched/wake_q.h>
35 #include <linux/syscalls.h>
36 #include <linux/audit.h>
37 #include <linux/seq_file.h>
38 #include <linux/rwsem.h>
39 #include <linux/nsproxy.h>
40 #include <linux/ipc_namespace.h>
41 #include <linux/rhashtable.h>
42 
43 #include <asm/current.h>
44 #include <linux/uaccess.h>
45 #include "util.h"
46 
47 /* one msq_queue structure for each present queue on the system */
48 struct msg_queue {
49 	struct kern_ipc_perm q_perm;
50 	time64_t q_stime;		/* last msgsnd time */
51 	time64_t q_rtime;		/* last msgrcv time */
52 	time64_t q_ctime;		/* last change time */
53 	unsigned long q_cbytes;		/* current number of bytes on queue */
54 	unsigned long q_qnum;		/* number of messages in queue */
55 	unsigned long q_qbytes;		/* max number of bytes on queue */
56 	struct pid *q_lspid;		/* pid of last msgsnd */
57 	struct pid *q_lrpid;		/* last receive pid */
58 
59 	struct list_head q_messages;
60 	struct list_head q_receivers;
61 	struct list_head q_senders;
62 } __randomize_layout;
63 
64 /*
65  * MSG_BARRIER Locking:
66  *
67  * Similar to the optimization used in ipc/mqueue.c, one syscall return path
68  * does not acquire any locks when it sees that a message exists in
69  * msg_receiver.r_msg. Therefore r_msg is set using smp_store_release()
70  * and accessed using READ_ONCE()+smp_acquire__after_ctrl_dep(). In addition,
71  * wake_q_add_safe() is used. See ipc/mqueue.c for more details
72  */
73 
74 /* one msg_receiver structure for each sleeping receiver */
75 struct msg_receiver {
76 	struct list_head	r_list;
77 	struct task_struct	*r_tsk;
78 
79 	int			r_mode;
80 	long			r_msgtype;
81 	long			r_maxsize;
82 
83 	struct msg_msg		*r_msg;
84 };
85 
86 /* one msg_sender for each sleeping sender */
87 struct msg_sender {
88 	struct list_head	list;
89 	struct task_struct	*tsk;
90 	size_t                  msgsz;
91 };
92 
93 #define SEARCH_ANY		1
94 #define SEARCH_EQUAL		2
95 #define SEARCH_NOTEQUAL		3
96 #define SEARCH_LESSEQUAL	4
97 #define SEARCH_NUMBER		5
98 
99 #define msg_ids(ns)	((ns)->ids[IPC_MSG_IDS])
100 
101 static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, int id)
102 {
103 	struct kern_ipc_perm *ipcp = ipc_obtain_object_idr(&msg_ids(ns), id);
104 
105 	if (IS_ERR(ipcp))
106 		return ERR_CAST(ipcp);
107 
108 	return container_of(ipcp, struct msg_queue, q_perm);
109 }
110 
111 static inline struct msg_queue *msq_obtain_object_check(struct ipc_namespace *ns,
112 							int id)
113 {
114 	struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&msg_ids(ns), id);
115 
116 	if (IS_ERR(ipcp))
117 		return ERR_CAST(ipcp);
118 
119 	return container_of(ipcp, struct msg_queue, q_perm);
120 }
121 
122 static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
123 {
124 	ipc_rmid(&msg_ids(ns), &s->q_perm);
125 }
126 
127 static void msg_rcu_free(struct rcu_head *head)
128 {
129 	struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
130 	struct msg_queue *msq = container_of(p, struct msg_queue, q_perm);
131 
132 	security_msg_queue_free(&msq->q_perm);
133 	kvfree(msq);
134 }
135 
136 /**
137  * newque - Create a new msg queue
138  * @ns: namespace
139  * @params: ptr to the structure that contains the key and msgflg
140  *
141  * Called with msg_ids.rwsem held (writer)
142  */
143 static int newque(struct ipc_namespace *ns, struct ipc_params *params)
144 {
145 	struct msg_queue *msq;
146 	int retval;
147 	key_t key = params->key;
148 	int msgflg = params->flg;
149 
150 	msq = kvmalloc(sizeof(*msq), GFP_KERNEL);
151 	if (unlikely(!msq))
152 		return -ENOMEM;
153 
154 	msq->q_perm.mode = msgflg & S_IRWXUGO;
155 	msq->q_perm.key = key;
156 
157 	msq->q_perm.security = NULL;
158 	retval = security_msg_queue_alloc(&msq->q_perm);
159 	if (retval) {
160 		kvfree(msq);
161 		return retval;
162 	}
163 
164 	msq->q_stime = msq->q_rtime = 0;
165 	msq->q_ctime = ktime_get_real_seconds();
166 	msq->q_cbytes = msq->q_qnum = 0;
167 	msq->q_qbytes = ns->msg_ctlmnb;
168 	msq->q_lspid = msq->q_lrpid = NULL;
169 	INIT_LIST_HEAD(&msq->q_messages);
170 	INIT_LIST_HEAD(&msq->q_receivers);
171 	INIT_LIST_HEAD(&msq->q_senders);
172 
173 	/* ipc_addid() locks msq upon success. */
174 	retval = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
175 	if (retval < 0) {
176 		ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
177 		return retval;
178 	}
179 
180 	ipc_unlock_object(&msq->q_perm);
181 	rcu_read_unlock();
182 
183 	return msq->q_perm.id;
184 }
185 
186 static inline bool msg_fits_inqueue(struct msg_queue *msq, size_t msgsz)
187 {
188 	return msgsz + msq->q_cbytes <= msq->q_qbytes &&
189 		1 + msq->q_qnum <= msq->q_qbytes;
190 }
191 
192 static inline void ss_add(struct msg_queue *msq,
193 			  struct msg_sender *mss, size_t msgsz)
194 {
195 	mss->tsk = current;
196 	mss->msgsz = msgsz;
197 	/*
198 	 * No memory barrier required: we did ipc_lock_object(),
199 	 * and the waker obtains that lock before calling wake_q_add().
200 	 */
201 	__set_current_state(TASK_INTERRUPTIBLE);
202 	list_add_tail(&mss->list, &msq->q_senders);
203 }
204 
205 static inline void ss_del(struct msg_sender *mss)
206 {
207 	if (mss->list.next)
208 		list_del(&mss->list);
209 }
210 
211 static void ss_wakeup(struct msg_queue *msq,
212 		      struct wake_q_head *wake_q, bool kill)
213 {
214 	struct msg_sender *mss, *t;
215 	struct task_struct *stop_tsk = NULL;
216 	struct list_head *h = &msq->q_senders;
217 
218 	list_for_each_entry_safe(mss, t, h, list) {
219 		if (kill)
220 			mss->list.next = NULL;
221 
222 		/*
223 		 * Stop at the first task we don't wakeup,
224 		 * we've already iterated the original
225 		 * sender queue.
226 		 */
227 		else if (stop_tsk == mss->tsk)
228 			break;
229 		/*
230 		 * We are not in an EIDRM scenario here, therefore
231 		 * verify that we really need to wakeup the task.
232 		 * To maintain current semantics and wakeup order,
233 		 * move the sender to the tail on behalf of the
234 		 * blocked task.
235 		 */
236 		else if (!msg_fits_inqueue(msq, mss->msgsz)) {
237 			if (!stop_tsk)
238 				stop_tsk = mss->tsk;
239 
240 			list_move_tail(&mss->list, &msq->q_senders);
241 			continue;
242 		}
243 
244 		wake_q_add(wake_q, mss->tsk);
245 	}
246 }
247 
248 static void expunge_all(struct msg_queue *msq, int res,
249 			struct wake_q_head *wake_q)
250 {
251 	struct msg_receiver *msr, *t;
252 
253 	list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
254 		get_task_struct(msr->r_tsk);
255 
256 		/* see MSG_BARRIER for purpose/pairing */
257 		smp_store_release(&msr->r_msg, ERR_PTR(res));
258 		wake_q_add_safe(wake_q, msr->r_tsk);
259 	}
260 }
261 
262 /*
263  * freeque() wakes up waiters on the sender and receiver waiting queue,
264  * removes the message queue from message queue ID IDR, and cleans up all the
265  * messages associated with this queue.
266  *
267  * msg_ids.rwsem (writer) and the spinlock for this message queue are held
268  * before freeque() is called. msg_ids.rwsem remains locked on exit.
269  */
270 static void freeque(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
271 {
272 	struct msg_msg *msg, *t;
273 	struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
274 	DEFINE_WAKE_Q(wake_q);
275 
276 	expunge_all(msq, -EIDRM, &wake_q);
277 	ss_wakeup(msq, &wake_q, true);
278 	msg_rmid(ns, msq);
279 	ipc_unlock_object(&msq->q_perm);
280 	wake_up_q(&wake_q);
281 	rcu_read_unlock();
282 
283 	list_for_each_entry_safe(msg, t, &msq->q_messages, m_list) {
284 		atomic_dec(&ns->msg_hdrs);
285 		free_msg(msg);
286 	}
287 	atomic_sub(msq->q_cbytes, &ns->msg_bytes);
288 	ipc_update_pid(&msq->q_lspid, NULL);
289 	ipc_update_pid(&msq->q_lrpid, NULL);
290 	ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
291 }
292 
293 long ksys_msgget(key_t key, int msgflg)
294 {
295 	struct ipc_namespace *ns;
296 	static const struct ipc_ops msg_ops = {
297 		.getnew = newque,
298 		.associate = security_msg_queue_associate,
299 	};
300 	struct ipc_params msg_params;
301 
302 	ns = current->nsproxy->ipc_ns;
303 
304 	msg_params.key = key;
305 	msg_params.flg = msgflg;
306 
307 	return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params);
308 }
309 
310 SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg)
311 {
312 	return ksys_msgget(key, msgflg);
313 }
314 
315 static inline unsigned long
316 copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version)
317 {
318 	switch (version) {
319 	case IPC_64:
320 		return copy_to_user(buf, in, sizeof(*in));
321 	case IPC_OLD:
322 	{
323 		struct msqid_ds out;
324 
325 		memset(&out, 0, sizeof(out));
326 
327 		ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm);
328 
329 		out.msg_stime		= in->msg_stime;
330 		out.msg_rtime		= in->msg_rtime;
331 		out.msg_ctime		= in->msg_ctime;
332 
333 		if (in->msg_cbytes > USHRT_MAX)
334 			out.msg_cbytes	= USHRT_MAX;
335 		else
336 			out.msg_cbytes	= in->msg_cbytes;
337 		out.msg_lcbytes		= in->msg_cbytes;
338 
339 		if (in->msg_qnum > USHRT_MAX)
340 			out.msg_qnum	= USHRT_MAX;
341 		else
342 			out.msg_qnum	= in->msg_qnum;
343 
344 		if (in->msg_qbytes > USHRT_MAX)
345 			out.msg_qbytes	= USHRT_MAX;
346 		else
347 			out.msg_qbytes	= in->msg_qbytes;
348 		out.msg_lqbytes		= in->msg_qbytes;
349 
350 		out.msg_lspid		= in->msg_lspid;
351 		out.msg_lrpid		= in->msg_lrpid;
352 
353 		return copy_to_user(buf, &out, sizeof(out));
354 	}
355 	default:
356 		return -EINVAL;
357 	}
358 }
359 
360 static inline unsigned long
361 copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version)
362 {
363 	switch (version) {
364 	case IPC_64:
365 		if (copy_from_user(out, buf, sizeof(*out)))
366 			return -EFAULT;
367 		return 0;
368 	case IPC_OLD:
369 	{
370 		struct msqid_ds tbuf_old;
371 
372 		if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
373 			return -EFAULT;
374 
375 		out->msg_perm.uid	= tbuf_old.msg_perm.uid;
376 		out->msg_perm.gid	= tbuf_old.msg_perm.gid;
377 		out->msg_perm.mode	= tbuf_old.msg_perm.mode;
378 
379 		if (tbuf_old.msg_qbytes == 0)
380 			out->msg_qbytes	= tbuf_old.msg_lqbytes;
381 		else
382 			out->msg_qbytes	= tbuf_old.msg_qbytes;
383 
384 		return 0;
385 	}
386 	default:
387 		return -EINVAL;
388 	}
389 }
390 
391 /*
392  * This function handles some msgctl commands which require the rwsem
393  * to be held in write mode.
394  * NOTE: no locks must be held, the rwsem is taken inside this function.
395  */
396 static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
397 			struct ipc64_perm *perm, int msg_qbytes)
398 {
399 	struct kern_ipc_perm *ipcp;
400 	struct msg_queue *msq;
401 	int err;
402 
403 	down_write(&msg_ids(ns).rwsem);
404 	rcu_read_lock();
405 
406 	ipcp = ipcctl_obtain_check(ns, &msg_ids(ns), msqid, cmd,
407 				      perm, msg_qbytes);
408 	if (IS_ERR(ipcp)) {
409 		err = PTR_ERR(ipcp);
410 		goto out_unlock1;
411 	}
412 
413 	msq = container_of(ipcp, struct msg_queue, q_perm);
414 
415 	err = security_msg_queue_msgctl(&msq->q_perm, cmd);
416 	if (err)
417 		goto out_unlock1;
418 
419 	switch (cmd) {
420 	case IPC_RMID:
421 		ipc_lock_object(&msq->q_perm);
422 		/* freeque unlocks the ipc object and rcu */
423 		freeque(ns, ipcp);
424 		goto out_up;
425 	case IPC_SET:
426 	{
427 		DEFINE_WAKE_Q(wake_q);
428 
429 		if (msg_qbytes > ns->msg_ctlmnb &&
430 		    !capable(CAP_SYS_RESOURCE)) {
431 			err = -EPERM;
432 			goto out_unlock1;
433 		}
434 
435 		ipc_lock_object(&msq->q_perm);
436 		err = ipc_update_perm(perm, ipcp);
437 		if (err)
438 			goto out_unlock0;
439 
440 		msq->q_qbytes = msg_qbytes;
441 
442 		msq->q_ctime = ktime_get_real_seconds();
443 		/*
444 		 * Sleeping receivers might be excluded by
445 		 * stricter permissions.
446 		 */
447 		expunge_all(msq, -EAGAIN, &wake_q);
448 		/*
449 		 * Sleeping senders might be able to send
450 		 * due to a larger queue size.
451 		 */
452 		ss_wakeup(msq, &wake_q, false);
453 		ipc_unlock_object(&msq->q_perm);
454 		wake_up_q(&wake_q);
455 
456 		goto out_unlock1;
457 	}
458 	default:
459 		err = -EINVAL;
460 		goto out_unlock1;
461 	}
462 
463 out_unlock0:
464 	ipc_unlock_object(&msq->q_perm);
465 out_unlock1:
466 	rcu_read_unlock();
467 out_up:
468 	up_write(&msg_ids(ns).rwsem);
469 	return err;
470 }
471 
472 static int msgctl_info(struct ipc_namespace *ns, int msqid,
473 			 int cmd, struct msginfo *msginfo)
474 {
475 	int err;
476 	int max_idx;
477 
478 	/*
479 	 * We must not return kernel stack data.
480 	 * due to padding, it's not enough
481 	 * to set all member fields.
482 	 */
483 	err = security_msg_queue_msgctl(NULL, cmd);
484 	if (err)
485 		return err;
486 
487 	memset(msginfo, 0, sizeof(*msginfo));
488 	msginfo->msgmni = ns->msg_ctlmni;
489 	msginfo->msgmax = ns->msg_ctlmax;
490 	msginfo->msgmnb = ns->msg_ctlmnb;
491 	msginfo->msgssz = MSGSSZ;
492 	msginfo->msgseg = MSGSEG;
493 	down_read(&msg_ids(ns).rwsem);
494 	if (cmd == MSG_INFO) {
495 		msginfo->msgpool = msg_ids(ns).in_use;
496 		msginfo->msgmap = atomic_read(&ns->msg_hdrs);
497 		msginfo->msgtql = atomic_read(&ns->msg_bytes);
498 	} else {
499 		msginfo->msgmap = MSGMAP;
500 		msginfo->msgpool = MSGPOOL;
501 		msginfo->msgtql = MSGTQL;
502 	}
503 	max_idx = ipc_get_maxidx(&msg_ids(ns));
504 	up_read(&msg_ids(ns).rwsem);
505 	return (max_idx < 0) ? 0 : max_idx;
506 }
507 
508 static int msgctl_stat(struct ipc_namespace *ns, int msqid,
509 			 int cmd, struct msqid64_ds *p)
510 {
511 	struct msg_queue *msq;
512 	int err;
513 
514 	memset(p, 0, sizeof(*p));
515 
516 	rcu_read_lock();
517 	if (cmd == MSG_STAT || cmd == MSG_STAT_ANY) {
518 		msq = msq_obtain_object(ns, msqid);
519 		if (IS_ERR(msq)) {
520 			err = PTR_ERR(msq);
521 			goto out_unlock;
522 		}
523 	} else { /* IPC_STAT */
524 		msq = msq_obtain_object_check(ns, msqid);
525 		if (IS_ERR(msq)) {
526 			err = PTR_ERR(msq);
527 			goto out_unlock;
528 		}
529 	}
530 
531 	/* see comment for SHM_STAT_ANY */
532 	if (cmd == MSG_STAT_ANY)
533 		audit_ipc_obj(&msq->q_perm);
534 	else {
535 		err = -EACCES;
536 		if (ipcperms(ns, &msq->q_perm, S_IRUGO))
537 			goto out_unlock;
538 	}
539 
540 	err = security_msg_queue_msgctl(&msq->q_perm, cmd);
541 	if (err)
542 		goto out_unlock;
543 
544 	ipc_lock_object(&msq->q_perm);
545 
546 	if (!ipc_valid_object(&msq->q_perm)) {
547 		ipc_unlock_object(&msq->q_perm);
548 		err = -EIDRM;
549 		goto out_unlock;
550 	}
551 
552 	kernel_to_ipc64_perm(&msq->q_perm, &p->msg_perm);
553 	p->msg_stime  = msq->q_stime;
554 	p->msg_rtime  = msq->q_rtime;
555 	p->msg_ctime  = msq->q_ctime;
556 #ifndef CONFIG_64BIT
557 	p->msg_stime_high = msq->q_stime >> 32;
558 	p->msg_rtime_high = msq->q_rtime >> 32;
559 	p->msg_ctime_high = msq->q_ctime >> 32;
560 #endif
561 	p->msg_cbytes = msq->q_cbytes;
562 	p->msg_qnum   = msq->q_qnum;
563 	p->msg_qbytes = msq->q_qbytes;
564 	p->msg_lspid  = pid_vnr(msq->q_lspid);
565 	p->msg_lrpid  = pid_vnr(msq->q_lrpid);
566 
567 	if (cmd == IPC_STAT) {
568 		/*
569 		 * As defined in SUS:
570 		 * Return 0 on success
571 		 */
572 		err = 0;
573 	} else {
574 		/*
575 		 * MSG_STAT and MSG_STAT_ANY (both Linux specific)
576 		 * Return the full id, including the sequence number
577 		 */
578 		err = msq->q_perm.id;
579 	}
580 
581 	ipc_unlock_object(&msq->q_perm);
582 out_unlock:
583 	rcu_read_unlock();
584 	return err;
585 }
586 
587 static long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf, int version)
588 {
589 	struct ipc_namespace *ns;
590 	struct msqid64_ds msqid64;
591 	int err;
592 
593 	if (msqid < 0 || cmd < 0)
594 		return -EINVAL;
595 
596 	ns = current->nsproxy->ipc_ns;
597 
598 	switch (cmd) {
599 	case IPC_INFO:
600 	case MSG_INFO: {
601 		struct msginfo msginfo;
602 		err = msgctl_info(ns, msqid, cmd, &msginfo);
603 		if (err < 0)
604 			return err;
605 		if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
606 			err = -EFAULT;
607 		return err;
608 	}
609 	case MSG_STAT:	/* msqid is an index rather than a msg queue id */
610 	case MSG_STAT_ANY:
611 	case IPC_STAT:
612 		err = msgctl_stat(ns, msqid, cmd, &msqid64);
613 		if (err < 0)
614 			return err;
615 		if (copy_msqid_to_user(buf, &msqid64, version))
616 			err = -EFAULT;
617 		return err;
618 	case IPC_SET:
619 		if (copy_msqid_from_user(&msqid64, buf, version))
620 			return -EFAULT;
621 		return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm,
622 				   msqid64.msg_qbytes);
623 	case IPC_RMID:
624 		return msgctl_down(ns, msqid, cmd, NULL, 0);
625 	default:
626 		return  -EINVAL;
627 	}
628 }
629 
630 SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
631 {
632 	return ksys_msgctl(msqid, cmd, buf, IPC_64);
633 }
634 
635 #ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
636 long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
637 {
638 	int version = ipc_parse_version(&cmd);
639 
640 	return ksys_msgctl(msqid, cmd, buf, version);
641 }
642 
643 SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
644 {
645 	return ksys_old_msgctl(msqid, cmd, buf);
646 }
647 #endif
648 
649 #ifdef CONFIG_COMPAT
650 
651 struct compat_msqid_ds {
652 	struct compat_ipc_perm msg_perm;
653 	compat_uptr_t msg_first;
654 	compat_uptr_t msg_last;
655 	old_time32_t msg_stime;
656 	old_time32_t msg_rtime;
657 	old_time32_t msg_ctime;
658 	compat_ulong_t msg_lcbytes;
659 	compat_ulong_t msg_lqbytes;
660 	unsigned short msg_cbytes;
661 	unsigned short msg_qnum;
662 	unsigned short msg_qbytes;
663 	compat_ipc_pid_t msg_lspid;
664 	compat_ipc_pid_t msg_lrpid;
665 };
666 
667 static int copy_compat_msqid_from_user(struct msqid64_ds *out, void __user *buf,
668 					int version)
669 {
670 	memset(out, 0, sizeof(*out));
671 	if (version == IPC_64) {
672 		struct compat_msqid64_ds __user *p = buf;
673 		if (get_compat_ipc64_perm(&out->msg_perm, &p->msg_perm))
674 			return -EFAULT;
675 		if (get_user(out->msg_qbytes, &p->msg_qbytes))
676 			return -EFAULT;
677 	} else {
678 		struct compat_msqid_ds __user *p = buf;
679 		if (get_compat_ipc_perm(&out->msg_perm, &p->msg_perm))
680 			return -EFAULT;
681 		if (get_user(out->msg_qbytes, &p->msg_qbytes))
682 			return -EFAULT;
683 	}
684 	return 0;
685 }
686 
687 static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in,
688 					int version)
689 {
690 	if (version == IPC_64) {
691 		struct compat_msqid64_ds v;
692 		memset(&v, 0, sizeof(v));
693 		to_compat_ipc64_perm(&v.msg_perm, &in->msg_perm);
694 		v.msg_stime	 = lower_32_bits(in->msg_stime);
695 		v.msg_stime_high = upper_32_bits(in->msg_stime);
696 		v.msg_rtime	 = lower_32_bits(in->msg_rtime);
697 		v.msg_rtime_high = upper_32_bits(in->msg_rtime);
698 		v.msg_ctime	 = lower_32_bits(in->msg_ctime);
699 		v.msg_ctime_high = upper_32_bits(in->msg_ctime);
700 		v.msg_cbytes = in->msg_cbytes;
701 		v.msg_qnum = in->msg_qnum;
702 		v.msg_qbytes = in->msg_qbytes;
703 		v.msg_lspid = in->msg_lspid;
704 		v.msg_lrpid = in->msg_lrpid;
705 		return copy_to_user(buf, &v, sizeof(v));
706 	} else {
707 		struct compat_msqid_ds v;
708 		memset(&v, 0, sizeof(v));
709 		to_compat_ipc_perm(&v.msg_perm, &in->msg_perm);
710 		v.msg_stime = in->msg_stime;
711 		v.msg_rtime = in->msg_rtime;
712 		v.msg_ctime = in->msg_ctime;
713 		v.msg_cbytes = in->msg_cbytes;
714 		v.msg_qnum = in->msg_qnum;
715 		v.msg_qbytes = in->msg_qbytes;
716 		v.msg_lspid = in->msg_lspid;
717 		v.msg_lrpid = in->msg_lrpid;
718 		return copy_to_user(buf, &v, sizeof(v));
719 	}
720 }
721 
722 static long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr, int version)
723 {
724 	struct ipc_namespace *ns;
725 	int err;
726 	struct msqid64_ds msqid64;
727 
728 	ns = current->nsproxy->ipc_ns;
729 
730 	if (msqid < 0 || cmd < 0)
731 		return -EINVAL;
732 
733 	switch (cmd & (~IPC_64)) {
734 	case IPC_INFO:
735 	case MSG_INFO: {
736 		struct msginfo msginfo;
737 		err = msgctl_info(ns, msqid, cmd, &msginfo);
738 		if (err < 0)
739 			return err;
740 		if (copy_to_user(uptr, &msginfo, sizeof(struct msginfo)))
741 			err = -EFAULT;
742 		return err;
743 	}
744 	case IPC_STAT:
745 	case MSG_STAT:
746 	case MSG_STAT_ANY:
747 		err = msgctl_stat(ns, msqid, cmd, &msqid64);
748 		if (err < 0)
749 			return err;
750 		if (copy_compat_msqid_to_user(uptr, &msqid64, version))
751 			err = -EFAULT;
752 		return err;
753 	case IPC_SET:
754 		if (copy_compat_msqid_from_user(&msqid64, uptr, version))
755 			return -EFAULT;
756 		return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm, msqid64.msg_qbytes);
757 	case IPC_RMID:
758 		return msgctl_down(ns, msqid, cmd, NULL, 0);
759 	default:
760 		return -EINVAL;
761 	}
762 }
763 
764 COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr)
765 {
766 	return compat_ksys_msgctl(msqid, cmd, uptr, IPC_64);
767 }
768 
769 #ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
770 long compat_ksys_old_msgctl(int msqid, int cmd, void __user *uptr)
771 {
772 	int version = compat_ipc_parse_version(&cmd);
773 
774 	return compat_ksys_msgctl(msqid, cmd, uptr, version);
775 }
776 
777 COMPAT_SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, void __user *, uptr)
778 {
779 	return compat_ksys_old_msgctl(msqid, cmd, uptr);
780 }
781 #endif
782 #endif
783 
784 static int testmsg(struct msg_msg *msg, long type, int mode)
785 {
786 	switch (mode) {
787 	case SEARCH_ANY:
788 	case SEARCH_NUMBER:
789 		return 1;
790 	case SEARCH_LESSEQUAL:
791 		if (msg->m_type <= type)
792 			return 1;
793 		break;
794 	case SEARCH_EQUAL:
795 		if (msg->m_type == type)
796 			return 1;
797 		break;
798 	case SEARCH_NOTEQUAL:
799 		if (msg->m_type != type)
800 			return 1;
801 		break;
802 	}
803 	return 0;
804 }
805 
806 static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg,
807 				 struct wake_q_head *wake_q)
808 {
809 	struct msg_receiver *msr, *t;
810 
811 	list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
812 		if (testmsg(msg, msr->r_msgtype, msr->r_mode) &&
813 		    !security_msg_queue_msgrcv(&msq->q_perm, msg, msr->r_tsk,
814 					       msr->r_msgtype, msr->r_mode)) {
815 
816 			list_del(&msr->r_list);
817 			if (msr->r_maxsize < msg->m_ts) {
818 				wake_q_add(wake_q, msr->r_tsk);
819 
820 				/* See expunge_all regarding memory barrier */
821 				smp_store_release(&msr->r_msg, ERR_PTR(-E2BIG));
822 			} else {
823 				ipc_update_pid(&msq->q_lrpid, task_pid(msr->r_tsk));
824 				msq->q_rtime = ktime_get_real_seconds();
825 
826 				wake_q_add(wake_q, msr->r_tsk);
827 
828 				/* See expunge_all regarding memory barrier */
829 				smp_store_release(&msr->r_msg, msg);
830 				return 1;
831 			}
832 		}
833 	}
834 
835 	return 0;
836 }
837 
838 static long do_msgsnd(int msqid, long mtype, void __user *mtext,
839 		size_t msgsz, int msgflg)
840 {
841 	struct msg_queue *msq;
842 	struct msg_msg *msg;
843 	int err;
844 	struct ipc_namespace *ns;
845 	DEFINE_WAKE_Q(wake_q);
846 
847 	ns = current->nsproxy->ipc_ns;
848 
849 	if (msgsz > ns->msg_ctlmax || (long) msgsz < 0 || msqid < 0)
850 		return -EINVAL;
851 	if (mtype < 1)
852 		return -EINVAL;
853 
854 	msg = load_msg(mtext, msgsz);
855 	if (IS_ERR(msg))
856 		return PTR_ERR(msg);
857 
858 	msg->m_type = mtype;
859 	msg->m_ts = msgsz;
860 
861 	rcu_read_lock();
862 	msq = msq_obtain_object_check(ns, msqid);
863 	if (IS_ERR(msq)) {
864 		err = PTR_ERR(msq);
865 		goto out_unlock1;
866 	}
867 
868 	ipc_lock_object(&msq->q_perm);
869 
870 	for (;;) {
871 		struct msg_sender s;
872 
873 		err = -EACCES;
874 		if (ipcperms(ns, &msq->q_perm, S_IWUGO))
875 			goto out_unlock0;
876 
877 		/* raced with RMID? */
878 		if (!ipc_valid_object(&msq->q_perm)) {
879 			err = -EIDRM;
880 			goto out_unlock0;
881 		}
882 
883 		err = security_msg_queue_msgsnd(&msq->q_perm, msg, msgflg);
884 		if (err)
885 			goto out_unlock0;
886 
887 		if (msg_fits_inqueue(msq, msgsz))
888 			break;
889 
890 		/* queue full, wait: */
891 		if (msgflg & IPC_NOWAIT) {
892 			err = -EAGAIN;
893 			goto out_unlock0;
894 		}
895 
896 		/* enqueue the sender and prepare to block */
897 		ss_add(msq, &s, msgsz);
898 
899 		if (!ipc_rcu_getref(&msq->q_perm)) {
900 			err = -EIDRM;
901 			goto out_unlock0;
902 		}
903 
904 		ipc_unlock_object(&msq->q_perm);
905 		rcu_read_unlock();
906 		schedule();
907 
908 		rcu_read_lock();
909 		ipc_lock_object(&msq->q_perm);
910 
911 		ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
912 		/* raced with RMID? */
913 		if (!ipc_valid_object(&msq->q_perm)) {
914 			err = -EIDRM;
915 			goto out_unlock0;
916 		}
917 		ss_del(&s);
918 
919 		if (signal_pending(current)) {
920 			err = -ERESTARTNOHAND;
921 			goto out_unlock0;
922 		}
923 
924 	}
925 
926 	ipc_update_pid(&msq->q_lspid, task_tgid(current));
927 	msq->q_stime = ktime_get_real_seconds();
928 
929 	if (!pipelined_send(msq, msg, &wake_q)) {
930 		/* no one is waiting for this message, enqueue it */
931 		list_add_tail(&msg->m_list, &msq->q_messages);
932 		msq->q_cbytes += msgsz;
933 		msq->q_qnum++;
934 		atomic_add(msgsz, &ns->msg_bytes);
935 		atomic_inc(&ns->msg_hdrs);
936 	}
937 
938 	err = 0;
939 	msg = NULL;
940 
941 out_unlock0:
942 	ipc_unlock_object(&msq->q_perm);
943 	wake_up_q(&wake_q);
944 out_unlock1:
945 	rcu_read_unlock();
946 	if (msg != NULL)
947 		free_msg(msg);
948 	return err;
949 }
950 
951 long ksys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz,
952 		 int msgflg)
953 {
954 	long mtype;
955 
956 	if (get_user(mtype, &msgp->mtype))
957 		return -EFAULT;
958 	return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
959 }
960 
961 SYSCALL_DEFINE4(msgsnd, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
962 		int, msgflg)
963 {
964 	return ksys_msgsnd(msqid, msgp, msgsz, msgflg);
965 }
966 
967 #ifdef CONFIG_COMPAT
968 
969 struct compat_msgbuf {
970 	compat_long_t mtype;
971 	char mtext[1];
972 };
973 
974 long compat_ksys_msgsnd(int msqid, compat_uptr_t msgp,
975 		       compat_ssize_t msgsz, int msgflg)
976 {
977 	struct compat_msgbuf __user *up = compat_ptr(msgp);
978 	compat_long_t mtype;
979 
980 	if (get_user(mtype, &up->mtype))
981 		return -EFAULT;
982 	return do_msgsnd(msqid, mtype, up->mtext, (ssize_t)msgsz, msgflg);
983 }
984 
985 COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp,
986 		       compat_ssize_t, msgsz, int, msgflg)
987 {
988 	return compat_ksys_msgsnd(msqid, msgp, msgsz, msgflg);
989 }
990 #endif
991 
992 static inline int convert_mode(long *msgtyp, int msgflg)
993 {
994 	if (msgflg & MSG_COPY)
995 		return SEARCH_NUMBER;
996 	/*
997 	 *  find message of correct type.
998 	 *  msgtyp = 0 => get first.
999 	 *  msgtyp > 0 => get first message of matching type.
1000 	 *  msgtyp < 0 => get message with least type must be < abs(msgtype).
1001 	 */
1002 	if (*msgtyp == 0)
1003 		return SEARCH_ANY;
1004 	if (*msgtyp < 0) {
1005 		if (*msgtyp == LONG_MIN) /* -LONG_MIN is undefined */
1006 			*msgtyp = LONG_MAX;
1007 		else
1008 			*msgtyp = -*msgtyp;
1009 		return SEARCH_LESSEQUAL;
1010 	}
1011 	if (msgflg & MSG_EXCEPT)
1012 		return SEARCH_NOTEQUAL;
1013 	return SEARCH_EQUAL;
1014 }
1015 
1016 static long do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
1017 {
1018 	struct msgbuf __user *msgp = dest;
1019 	size_t msgsz;
1020 
1021 	if (put_user(msg->m_type, &msgp->mtype))
1022 		return -EFAULT;
1023 
1024 	msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz;
1025 	if (store_msg(msgp->mtext, msg, msgsz))
1026 		return -EFAULT;
1027 	return msgsz;
1028 }
1029 
1030 #ifdef CONFIG_CHECKPOINT_RESTORE
1031 /*
1032  * This function creates new kernel message structure, large enough to store
1033  * bufsz message bytes.
1034  */
1035 static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
1036 {
1037 	struct msg_msg *copy;
1038 
1039 	/*
1040 	 * Create dummy message to copy real message to.
1041 	 */
1042 	copy = load_msg(buf, bufsz);
1043 	if (!IS_ERR(copy))
1044 		copy->m_ts = bufsz;
1045 	return copy;
1046 }
1047 
1048 static inline void free_copy(struct msg_msg *copy)
1049 {
1050 	if (copy)
1051 		free_msg(copy);
1052 }
1053 #else
1054 static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz)
1055 {
1056 	return ERR_PTR(-ENOSYS);
1057 }
1058 
1059 static inline void free_copy(struct msg_msg *copy)
1060 {
1061 }
1062 #endif
1063 
1064 static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode)
1065 {
1066 	struct msg_msg *msg, *found = NULL;
1067 	long count = 0;
1068 
1069 	list_for_each_entry(msg, &msq->q_messages, m_list) {
1070 		if (testmsg(msg, *msgtyp, mode) &&
1071 		    !security_msg_queue_msgrcv(&msq->q_perm, msg, current,
1072 					       *msgtyp, mode)) {
1073 			if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) {
1074 				*msgtyp = msg->m_type - 1;
1075 				found = msg;
1076 			} else if (mode == SEARCH_NUMBER) {
1077 				if (*msgtyp == count)
1078 					return msg;
1079 			} else
1080 				return msg;
1081 			count++;
1082 		}
1083 	}
1084 
1085 	return found ?: ERR_PTR(-EAGAIN);
1086 }
1087 
1088 static long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgflg,
1089 	       long (*msg_handler)(void __user *, struct msg_msg *, size_t))
1090 {
1091 	int mode;
1092 	struct msg_queue *msq;
1093 	struct ipc_namespace *ns;
1094 	struct msg_msg *msg, *copy = NULL;
1095 	DEFINE_WAKE_Q(wake_q);
1096 
1097 	ns = current->nsproxy->ipc_ns;
1098 
1099 	if (msqid < 0 || (long) bufsz < 0)
1100 		return -EINVAL;
1101 
1102 	if (msgflg & MSG_COPY) {
1103 		if ((msgflg & MSG_EXCEPT) || !(msgflg & IPC_NOWAIT))
1104 			return -EINVAL;
1105 		copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax));
1106 		if (IS_ERR(copy))
1107 			return PTR_ERR(copy);
1108 	}
1109 	mode = convert_mode(&msgtyp, msgflg);
1110 
1111 	rcu_read_lock();
1112 	msq = msq_obtain_object_check(ns, msqid);
1113 	if (IS_ERR(msq)) {
1114 		rcu_read_unlock();
1115 		free_copy(copy);
1116 		return PTR_ERR(msq);
1117 	}
1118 
1119 	for (;;) {
1120 		struct msg_receiver msr_d;
1121 
1122 		msg = ERR_PTR(-EACCES);
1123 		if (ipcperms(ns, &msq->q_perm, S_IRUGO))
1124 			goto out_unlock1;
1125 
1126 		ipc_lock_object(&msq->q_perm);
1127 
1128 		/* raced with RMID? */
1129 		if (!ipc_valid_object(&msq->q_perm)) {
1130 			msg = ERR_PTR(-EIDRM);
1131 			goto out_unlock0;
1132 		}
1133 
1134 		msg = find_msg(msq, &msgtyp, mode);
1135 		if (!IS_ERR(msg)) {
1136 			/*
1137 			 * Found a suitable message.
1138 			 * Unlink it from the queue.
1139 			 */
1140 			if ((bufsz < msg->m_ts) && !(msgflg & MSG_NOERROR)) {
1141 				msg = ERR_PTR(-E2BIG);
1142 				goto out_unlock0;
1143 			}
1144 			/*
1145 			 * If we are copying, then do not unlink message and do
1146 			 * not update queue parameters.
1147 			 */
1148 			if (msgflg & MSG_COPY) {
1149 				msg = copy_msg(msg, copy);
1150 				goto out_unlock0;
1151 			}
1152 
1153 			list_del(&msg->m_list);
1154 			msq->q_qnum--;
1155 			msq->q_rtime = ktime_get_real_seconds();
1156 			ipc_update_pid(&msq->q_lrpid, task_tgid(current));
1157 			msq->q_cbytes -= msg->m_ts;
1158 			atomic_sub(msg->m_ts, &ns->msg_bytes);
1159 			atomic_dec(&ns->msg_hdrs);
1160 			ss_wakeup(msq, &wake_q, false);
1161 
1162 			goto out_unlock0;
1163 		}
1164 
1165 		/* No message waiting. Wait for a message */
1166 		if (msgflg & IPC_NOWAIT) {
1167 			msg = ERR_PTR(-ENOMSG);
1168 			goto out_unlock0;
1169 		}
1170 
1171 		list_add_tail(&msr_d.r_list, &msq->q_receivers);
1172 		msr_d.r_tsk = current;
1173 		msr_d.r_msgtype = msgtyp;
1174 		msr_d.r_mode = mode;
1175 		if (msgflg & MSG_NOERROR)
1176 			msr_d.r_maxsize = INT_MAX;
1177 		else
1178 			msr_d.r_maxsize = bufsz;
1179 
1180 		/* memory barrier not require due to ipc_lock_object() */
1181 		WRITE_ONCE(msr_d.r_msg, ERR_PTR(-EAGAIN));
1182 
1183 		/* memory barrier not required, we own ipc_lock_object() */
1184 		__set_current_state(TASK_INTERRUPTIBLE);
1185 
1186 		ipc_unlock_object(&msq->q_perm);
1187 		rcu_read_unlock();
1188 		schedule();
1189 
1190 		/*
1191 		 * Lockless receive, part 1:
1192 		 * We don't hold a reference to the queue and getting a
1193 		 * reference would defeat the idea of a lockless operation,
1194 		 * thus the code relies on rcu to guarantee the existence of
1195 		 * msq:
1196 		 * Prior to destruction, expunge_all(-EIRDM) changes r_msg.
1197 		 * Thus if r_msg is -EAGAIN, then the queue not yet destroyed.
1198 		 */
1199 		rcu_read_lock();
1200 
1201 		/*
1202 		 * Lockless receive, part 2:
1203 		 * The work in pipelined_send() and expunge_all():
1204 		 * - Set pointer to message
1205 		 * - Queue the receiver task for later wakeup
1206 		 * - Wake up the process after the lock is dropped.
1207 		 *
1208 		 * Should the process wake up before this wakeup (due to a
1209 		 * signal) it will either see the message and continue ...
1210 		 */
1211 		msg = READ_ONCE(msr_d.r_msg);
1212 		if (msg != ERR_PTR(-EAGAIN)) {
1213 			/* see MSG_BARRIER for purpose/pairing */
1214 			smp_acquire__after_ctrl_dep();
1215 
1216 			goto out_unlock1;
1217 		}
1218 
1219 		 /*
1220 		  * ... or see -EAGAIN, acquire the lock to check the message
1221 		  * again.
1222 		  */
1223 		ipc_lock_object(&msq->q_perm);
1224 
1225 		msg = READ_ONCE(msr_d.r_msg);
1226 		if (msg != ERR_PTR(-EAGAIN))
1227 			goto out_unlock0;
1228 
1229 		list_del(&msr_d.r_list);
1230 		if (signal_pending(current)) {
1231 			msg = ERR_PTR(-ERESTARTNOHAND);
1232 			goto out_unlock0;
1233 		}
1234 
1235 		ipc_unlock_object(&msq->q_perm);
1236 	}
1237 
1238 out_unlock0:
1239 	ipc_unlock_object(&msq->q_perm);
1240 	wake_up_q(&wake_q);
1241 out_unlock1:
1242 	rcu_read_unlock();
1243 	if (IS_ERR(msg)) {
1244 		free_copy(copy);
1245 		return PTR_ERR(msg);
1246 	}
1247 
1248 	bufsz = msg_handler(buf, msg, bufsz);
1249 	free_msg(msg);
1250 
1251 	return bufsz;
1252 }
1253 
1254 long ksys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz,
1255 		 long msgtyp, int msgflg)
1256 {
1257 	return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill);
1258 }
1259 
1260 SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz,
1261 		long, msgtyp, int, msgflg)
1262 {
1263 	return ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
1264 }
1265 
1266 #ifdef CONFIG_COMPAT
1267 static long compat_do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
1268 {
1269 	struct compat_msgbuf __user *msgp = dest;
1270 	size_t msgsz;
1271 
1272 	if (put_user(msg->m_type, &msgp->mtype))
1273 		return -EFAULT;
1274 
1275 	msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz;
1276 	if (store_msg(msgp->mtext, msg, msgsz))
1277 		return -EFAULT;
1278 	return msgsz;
1279 }
1280 
1281 long compat_ksys_msgrcv(int msqid, compat_uptr_t msgp, compat_ssize_t msgsz,
1282 			compat_long_t msgtyp, int msgflg)
1283 {
1284 	return do_msgrcv(msqid, compat_ptr(msgp), (ssize_t)msgsz, (long)msgtyp,
1285 			 msgflg, compat_do_msg_fill);
1286 }
1287 
1288 COMPAT_SYSCALL_DEFINE5(msgrcv, int, msqid, compat_uptr_t, msgp,
1289 		       compat_ssize_t, msgsz, compat_long_t, msgtyp,
1290 		       int, msgflg)
1291 {
1292 	return compat_ksys_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
1293 }
1294 #endif
1295 
1296 void msg_init_ns(struct ipc_namespace *ns)
1297 {
1298 	ns->msg_ctlmax = MSGMAX;
1299 	ns->msg_ctlmnb = MSGMNB;
1300 	ns->msg_ctlmni = MSGMNI;
1301 
1302 	atomic_set(&ns->msg_bytes, 0);
1303 	atomic_set(&ns->msg_hdrs, 0);
1304 	ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
1305 }
1306 
1307 #ifdef CONFIG_IPC_NS
1308 void msg_exit_ns(struct ipc_namespace *ns)
1309 {
1310 	free_ipcs(ns, &msg_ids(ns), freeque);
1311 	idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
1312 	rhashtable_destroy(&ns->ids[IPC_MSG_IDS].key_ht);
1313 }
1314 #endif
1315 
1316 #ifdef CONFIG_PROC_FS
1317 static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
1318 {
1319 	struct pid_namespace *pid_ns = ipc_seq_pid_ns(s);
1320 	struct user_namespace *user_ns = seq_user_ns(s);
1321 	struct kern_ipc_perm *ipcp = it;
1322 	struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm);
1323 
1324 	seq_printf(s,
1325 		   "%10d %10d  %4o  %10lu %10lu %5u %5u %5u %5u %5u %5u %10llu %10llu %10llu\n",
1326 		   msq->q_perm.key,
1327 		   msq->q_perm.id,
1328 		   msq->q_perm.mode,
1329 		   msq->q_cbytes,
1330 		   msq->q_qnum,
1331 		   pid_nr_ns(msq->q_lspid, pid_ns),
1332 		   pid_nr_ns(msq->q_lrpid, pid_ns),
1333 		   from_kuid_munged(user_ns, msq->q_perm.uid),
1334 		   from_kgid_munged(user_ns, msq->q_perm.gid),
1335 		   from_kuid_munged(user_ns, msq->q_perm.cuid),
1336 		   from_kgid_munged(user_ns, msq->q_perm.cgid),
1337 		   msq->q_stime,
1338 		   msq->q_rtime,
1339 		   msq->q_ctime);
1340 
1341 	return 0;
1342 }
1343 #endif
1344 
1345 void __init msg_init(void)
1346 {
1347 	msg_init_ns(&init_ipc_ns);
1348 
1349 	ipc_init_proc_interface("sysvipc/msg",
1350 				"       key      msqid perms      cbytes       qnum lspid lrpid   uid   gid  cuid  cgid      stime      rtime      ctime\n",
1351 				IPC_MSG_IDS, sysvipc_msg_proc_show);
1352 }
1353