sysv_shm.c revision 284665
1/*	$NetBSD: sysv_shm.c,v 1.23 1994/07/04 23:25:12 glass Exp $	*/
2/*-
3 * Copyright (c) 1994 Adam Glass and Charles Hannum.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by Adam Glass and Charles
16 *	Hannum.
17 * 4. The names of the authors may not be used to endorse or promote products
18 *    derived from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31/*-
32 * Copyright (c) 2003-2005 McAfee, Inc.
33 * All rights reserved.
34 *
35 * This software was developed for the FreeBSD Project in part by McAfee
36 * Research, the Security Research Division of McAfee, Inc under DARPA/SPAWAR
37 * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS research
38 * program.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 *    notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 *    notice, this list of conditions and the following disclaimer in the
47 *    documentation and/or other materials provided with the distribution.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 */
61
62#include <sys/cdefs.h>
63__FBSDID("$FreeBSD: stable/10/sys/kern/sysv_shm.c 284665 2015-06-21 06:28:26Z trasz $");
64
65#include "opt_compat.h"
66#include "opt_sysvipc.h"
67
68#include <sys/param.h>
69#include <sys/systm.h>
70#include <sys/kernel.h>
71#include <sys/limits.h>
72#include <sys/lock.h>
73#include <sys/sysctl.h>
74#include <sys/shm.h>
75#include <sys/proc.h>
76#include <sys/malloc.h>
77#include <sys/mman.h>
78#include <sys/module.h>
79#include <sys/mutex.h>
80#include <sys/racct.h>
81#include <sys/resourcevar.h>
82#include <sys/rwlock.h>
83#include <sys/stat.h>
84#include <sys/syscall.h>
85#include <sys/syscallsubr.h>
86#include <sys/sysent.h>
87#include <sys/sysproto.h>
88#include <sys/jail.h>
89
90#include <security/mac/mac_framework.h>
91
92#include <vm/vm.h>
93#include <vm/vm_param.h>
94#include <vm/pmap.h>
95#include <vm/vm_object.h>
96#include <vm/vm_map.h>
97#include <vm/vm_page.h>
98#include <vm/vm_pager.h>
99
100FEATURE(sysv_shm, "System V shared memory segments support");
101
102static MALLOC_DEFINE(M_SHM, "shm", "SVID compatible shared memory segments");
103
104static int shmget_allocate_segment(struct thread *td,
105    struct shmget_args *uap, int mode);
106static int shmget_existing(struct thread *td, struct shmget_args *uap,
107    int mode, int segnum);
108
109#define	SHMSEG_FREE     	0x0200
110#define	SHMSEG_REMOVED  	0x0400
111#define	SHMSEG_ALLOCATED	0x0800
112
113static int shm_last_free, shm_nused, shmalloced;
114vm_size_t shm_committed;
115static struct shmid_kernel	*shmsegs;
116
117struct shmmap_state {
118	vm_offset_t va;
119	int shmid;
120};
121
122static void shm_deallocate_segment(struct shmid_kernel *);
123static int shm_find_segment_by_key(key_t);
124static struct shmid_kernel *shm_find_segment(int, bool);
125static int shm_delete_mapping(struct vmspace *vm, struct shmmap_state *);
126static void shmrealloc(void);
127static int shminit(void);
128static int sysvshm_modload(struct module *, int, void *);
129static int shmunload(void);
130static void shmexit_myhook(struct vmspace *vm);
131static void shmfork_myhook(struct proc *p1, struct proc *p2);
132static int sysctl_shmsegs(SYSCTL_HANDLER_ARGS);
133
134/*
135 * Tuneable values.
136 */
137#ifndef SHMMAXPGS
138#define	SHMMAXPGS	131072	/* Note: sysv shared memory is swap backed. */
139#endif
140#ifndef SHMMAX
141#define	SHMMAX	(SHMMAXPGS*PAGE_SIZE)
142#endif
143#ifndef SHMMIN
144#define	SHMMIN	1
145#endif
146#ifndef SHMMNI
147#define	SHMMNI	192
148#endif
149#ifndef SHMSEG
150#define	SHMSEG	128
151#endif
152#ifndef SHMALL
153#define	SHMALL	(SHMMAXPGS)
154#endif
155
156struct	shminfo shminfo = {
157	SHMMAX,
158	SHMMIN,
159	SHMMNI,
160	SHMSEG,
161	SHMALL
162};
163
164static int shm_use_phys;
165static int shm_allow_removed;
166
167SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmax, CTLFLAG_RW, &shminfo.shmmax, 0,
168    "Maximum shared memory segment size");
169SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmin, CTLFLAG_RW, &shminfo.shmmin, 0,
170    "Minimum shared memory segment size");
171SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmni, CTLFLAG_RDTUN, &shminfo.shmmni, 0,
172    "Number of shared memory identifiers");
173SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmseg, CTLFLAG_RDTUN, &shminfo.shmseg, 0,
174    "Number of segments per process");
175SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmall, CTLFLAG_RW, &shminfo.shmall, 0,
176    "Maximum number of pages available for shared memory");
177SYSCTL_INT(_kern_ipc, OID_AUTO, shm_use_phys, CTLFLAG_RW,
178    &shm_use_phys, 0, "Enable/Disable locking of shared memory pages in core");
179SYSCTL_INT(_kern_ipc, OID_AUTO, shm_allow_removed, CTLFLAG_RW,
180    &shm_allow_removed, 0,
181    "Enable/Disable attachment to attached segments marked for removal");
182SYSCTL_PROC(_kern_ipc, OID_AUTO, shmsegs, CTLTYPE_OPAQUE | CTLFLAG_RD |
183    CTLFLAG_MPSAFE, NULL, 0, sysctl_shmsegs, "",
184    "Current number of shared memory segments allocated");
185
186static struct sx sysvshmsx;
187#define	SYSVSHM_LOCK()		sx_xlock(&sysvshmsx)
188#define	SYSVSHM_UNLOCK()	sx_xunlock(&sysvshmsx)
189#define	SYSVSHM_ASSERT_LOCKED()	sx_assert(&sysvshmsx, SA_XLOCKED)
190
191static int
192shm_find_segment_by_key(key_t key)
193{
194	int i;
195
196	for (i = 0; i < shmalloced; i++)
197		if ((shmsegs[i].u.shm_perm.mode & SHMSEG_ALLOCATED) &&
198		    shmsegs[i].u.shm_perm.key == key)
199			return (i);
200	return (-1);
201}
202
203/*
204 * Finds segment either by shmid if is_shmid is true, or by segnum if
205 * is_shmid is false.
206 */
207static struct shmid_kernel *
208shm_find_segment(int arg, bool is_shmid)
209{
210	struct shmid_kernel *shmseg;
211	int segnum;
212
213	segnum = is_shmid ? IPCID_TO_IX(arg) : arg;
214	if (segnum < 0 || segnum >= shmalloced)
215		return (NULL);
216	shmseg = &shmsegs[segnum];
217	if ((shmseg->u.shm_perm.mode & SHMSEG_ALLOCATED) == 0 ||
218	    (!shm_allow_removed &&
219	     (shmseg->u.shm_perm.mode & SHMSEG_REMOVED) != 0) ||
220	    (is_shmid && shmseg->u.shm_perm.seq != IPCID_TO_SEQ(arg)))
221		return (NULL);
222	return (shmseg);
223}
224
225static void
226shm_deallocate_segment(struct shmid_kernel *shmseg)
227{
228	vm_size_t size;
229
230	SYSVSHM_ASSERT_LOCKED();
231
232	vm_object_deallocate(shmseg->object);
233	shmseg->object = NULL;
234	size = round_page(shmseg->u.shm_segsz);
235	shm_committed -= btoc(size);
236	shm_nused--;
237	shmseg->u.shm_perm.mode = SHMSEG_FREE;
238#ifdef MAC
239	mac_sysvshm_cleanup(shmseg);
240#endif
241	racct_sub_cred(shmseg->cred, RACCT_NSHM, 1);
242	racct_sub_cred(shmseg->cred, RACCT_SHMSIZE, size);
243	crfree(shmseg->cred);
244	shmseg->cred = NULL;
245}
246
247static int
248shm_delete_mapping(struct vmspace *vm, struct shmmap_state *shmmap_s)
249{
250	struct shmid_kernel *shmseg;
251	int segnum, result;
252	vm_size_t size;
253
254	SYSVSHM_ASSERT_LOCKED();
255	segnum = IPCID_TO_IX(shmmap_s->shmid);
256	KASSERT(segnum >= 0 && segnum < shmalloced,
257	    ("segnum %d shmalloced %d", segnum, shmalloced));
258
259	shmseg = &shmsegs[segnum];
260	size = round_page(shmseg->u.shm_segsz);
261	result = vm_map_remove(&vm->vm_map, shmmap_s->va, shmmap_s->va + size);
262	if (result != KERN_SUCCESS)
263		return (EINVAL);
264	shmmap_s->shmid = -1;
265	shmseg->u.shm_dtime = time_second;
266	if ((--shmseg->u.shm_nattch <= 0) &&
267	    (shmseg->u.shm_perm.mode & SHMSEG_REMOVED)) {
268		shm_deallocate_segment(shmseg);
269		shm_last_free = segnum;
270	}
271	return (0);
272}
273
274static int
275kern_shmdt_locked(struct thread *td, const void *shmaddr)
276{
277	struct proc *p = td->td_proc;
278	struct shmmap_state *shmmap_s;
279#ifdef MAC
280	struct shmid_kernel *shmsegptr;
281#endif
282	int error, i;
283
284	SYSVSHM_ASSERT_LOCKED();
285	if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
286		return (ENOSYS);
287	shmmap_s = p->p_vmspace->vm_shm;
288 	if (shmmap_s == NULL)
289		return (EINVAL);
290	for (i = 0; i < shminfo.shmseg; i++, shmmap_s++) {
291		if (shmmap_s->shmid != -1 &&
292		    shmmap_s->va == (vm_offset_t)shmaddr) {
293			break;
294		}
295	}
296	if (i == shminfo.shmseg)
297		return (EINVAL);
298#ifdef MAC
299	shmsegptr = &shmsegs[IPCID_TO_IX(shmmap_s->shmid)];
300	error = mac_sysvshm_check_shmdt(td->td_ucred, shmsegptr);
301	if (error != 0)
302		return (error);
303#endif
304	error = shm_delete_mapping(p->p_vmspace, shmmap_s);
305	return (error);
306}
307
308#ifndef _SYS_SYSPROTO_H_
309struct shmdt_args {
310	const void *shmaddr;
311};
312#endif
313int
314sys_shmdt(struct thread *td, struct shmdt_args *uap)
315{
316	int error;
317
318	SYSVSHM_LOCK();
319	error = kern_shmdt_locked(td, uap->shmaddr);
320	SYSVSHM_UNLOCK();
321	return (error);
322}
323
324static int
325kern_shmat_locked(struct thread *td, int shmid, const void *shmaddr,
326    int shmflg)
327{
328	struct proc *p = td->td_proc;
329	struct shmid_kernel *shmseg;
330	struct shmmap_state *shmmap_s;
331	vm_offset_t attach_va;
332	vm_prot_t prot;
333	vm_size_t size;
334	int error, i, rv;
335
336	SYSVSHM_ASSERT_LOCKED();
337	if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
338		return (ENOSYS);
339	shmmap_s = p->p_vmspace->vm_shm;
340	if (shmmap_s == NULL) {
341		shmmap_s = malloc(shminfo.shmseg * sizeof(struct shmmap_state),
342		    M_SHM, M_WAITOK);
343		for (i = 0; i < shminfo.shmseg; i++)
344			shmmap_s[i].shmid = -1;
345		KASSERT(p->p_vmspace->vm_shm == NULL, ("raced"));
346		p->p_vmspace->vm_shm = shmmap_s;
347	}
348	shmseg = shm_find_segment(shmid, true);
349	if (shmseg == NULL)
350		return (EINVAL);
351	error = ipcperm(td, &shmseg->u.shm_perm,
352	    (shmflg & SHM_RDONLY) ? IPC_R : IPC_R|IPC_W);
353	if (error != 0)
354		return (error);
355#ifdef MAC
356	error = mac_sysvshm_check_shmat(td->td_ucred, shmseg, shmflg);
357	if (error != 0)
358		return (error);
359#endif
360	for (i = 0; i < shminfo.shmseg; i++) {
361		if (shmmap_s->shmid == -1)
362			break;
363		shmmap_s++;
364	}
365	if (i >= shminfo.shmseg)
366		return (EMFILE);
367	size = round_page(shmseg->u.shm_segsz);
368	prot = VM_PROT_READ;
369	if ((shmflg & SHM_RDONLY) == 0)
370		prot |= VM_PROT_WRITE;
371	if (shmaddr != NULL) {
372		if ((shmflg & SHM_RND) != 0)
373			attach_va = (vm_offset_t)shmaddr & ~(SHMLBA-1);
374		else if (((vm_offset_t)shmaddr & (SHMLBA-1)) == 0)
375			attach_va = (vm_offset_t)shmaddr;
376		else
377			return (EINVAL);
378	} else {
379		/*
380		 * This is just a hint to vm_map_find() about where to
381		 * put it.
382		 */
383		PROC_LOCK(p);
384		attach_va = round_page((vm_offset_t)p->p_vmspace->vm_daddr +
385		    lim_max(p, RLIMIT_DATA));
386		PROC_UNLOCK(p);
387	}
388
389	vm_object_reference(shmseg->object);
390	rv = vm_map_find(&p->p_vmspace->vm_map, shmseg->object,
391	    0, &attach_va, size, 0, shmaddr != NULL ? VMFS_NO_SPACE :
392	    VMFS_OPTIMAL_SPACE, prot, prot, MAP_INHERIT_SHARE);
393	if (rv != KERN_SUCCESS) {
394		vm_object_deallocate(shmseg->object);
395		return (ENOMEM);
396	}
397
398	shmmap_s->va = attach_va;
399	shmmap_s->shmid = shmid;
400	shmseg->u.shm_lpid = p->p_pid;
401	shmseg->u.shm_atime = time_second;
402	shmseg->u.shm_nattch++;
403	td->td_retval[0] = attach_va;
404	return (error);
405}
406
407int
408kern_shmat(struct thread *td, int shmid, const void *shmaddr, int shmflg)
409{
410	int error;
411
412	SYSVSHM_LOCK();
413	error = kern_shmat_locked(td, shmid, shmaddr, shmflg);
414	SYSVSHM_UNLOCK();
415	return (error);
416}
417
418#ifndef _SYS_SYSPROTO_H_
419struct shmat_args {
420	int shmid;
421	const void *shmaddr;
422	int shmflg;
423};
424#endif
425int
426sys_shmat(struct thread *td, struct shmat_args *uap)
427{
428
429	return (kern_shmat(td, uap->shmid, uap->shmaddr, uap->shmflg));
430}
431
432static int
433kern_shmctl_locked(struct thread *td, int shmid, int cmd, void *buf,
434    size_t *bufsz)
435{
436	struct shmid_kernel *shmseg;
437	struct shmid_ds *shmidp;
438	struct shm_info shm_info;
439	int error;
440
441	SYSVSHM_ASSERT_LOCKED();
442
443	if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
444		return (ENOSYS);
445
446	error = 0;
447	switch (cmd) {
448	/*
449	 * It is possible that kern_shmctl is being called from the Linux ABI
450	 * layer, in which case, we will need to implement IPC_INFO.  It should
451	 * be noted that other shmctl calls will be funneled through here for
452	 * Linix binaries as well.
453	 *
454	 * NB: The Linux ABI layer will convert this data to structure(s) more
455	 * consistent with the Linux ABI.
456	 */
457	case IPC_INFO:
458		memcpy(buf, &shminfo, sizeof(shminfo));
459		if (bufsz)
460			*bufsz = sizeof(shminfo);
461		td->td_retval[0] = shmalloced;
462		return (0);
463	case SHM_INFO: {
464		shm_info.used_ids = shm_nused;
465		shm_info.shm_rss = 0;	/*XXX where to get from ? */
466		shm_info.shm_tot = 0;	/*XXX where to get from ? */
467		shm_info.shm_swp = 0;	/*XXX where to get from ? */
468		shm_info.swap_attempts = 0;	/*XXX where to get from ? */
469		shm_info.swap_successes = 0;	/*XXX where to get from ? */
470		memcpy(buf, &shm_info, sizeof(shm_info));
471		if (bufsz != NULL)
472			*bufsz = sizeof(shm_info);
473		td->td_retval[0] = shmalloced;
474		return (0);
475	}
476	}
477	shmseg = shm_find_segment(shmid, cmd != SHM_STAT);
478	if (shmseg == NULL)
479		return (EINVAL);
480#ifdef MAC
481	error = mac_sysvshm_check_shmctl(td->td_ucred, shmseg, cmd);
482	if (error != 0)
483		return (error);
484#endif
485	switch (cmd) {
486	case SHM_STAT:
487	case IPC_STAT:
488		error = ipcperm(td, &shmseg->u.shm_perm, IPC_R);
489		if (error != 0)
490			return (error);
491		memcpy(buf, &shmseg->u, sizeof(struct shmid_ds));
492		if (bufsz != NULL)
493			*bufsz = sizeof(struct shmid_ds);
494		if (cmd == SHM_STAT) {
495			td->td_retval[0] = IXSEQ_TO_IPCID(shmid,
496			    shmseg->u.shm_perm);
497		}
498		break;
499	case IPC_SET:
500		shmidp = (struct shmid_ds *)buf;
501		error = ipcperm(td, &shmseg->u.shm_perm, IPC_M);
502		if (error != 0)
503			return (error);
504		shmseg->u.shm_perm.uid = shmidp->shm_perm.uid;
505		shmseg->u.shm_perm.gid = shmidp->shm_perm.gid;
506		shmseg->u.shm_perm.mode =
507		    (shmseg->u.shm_perm.mode & ~ACCESSPERMS) |
508		    (shmidp->shm_perm.mode & ACCESSPERMS);
509		shmseg->u.shm_ctime = time_second;
510		break;
511	case IPC_RMID:
512		error = ipcperm(td, &shmseg->u.shm_perm, IPC_M);
513		if (error != 0)
514			return (error);
515		shmseg->u.shm_perm.key = IPC_PRIVATE;
516		shmseg->u.shm_perm.mode |= SHMSEG_REMOVED;
517		if (shmseg->u.shm_nattch <= 0) {
518			shm_deallocate_segment(shmseg);
519			shm_last_free = IPCID_TO_IX(shmid);
520		}
521		break;
522#if 0
523	case SHM_LOCK:
524	case SHM_UNLOCK:
525#endif
526	default:
527		error = EINVAL;
528		break;
529	}
530	return (error);
531}
532
533int
534kern_shmctl(struct thread *td, int shmid, int cmd, void *buf, size_t *bufsz)
535{
536	int error;
537
538	SYSVSHM_LOCK();
539	error = kern_shmctl_locked(td, shmid, cmd, buf, bufsz);
540	SYSVSHM_UNLOCK();
541	return (error);
542}
543
544
545#ifndef _SYS_SYSPROTO_H_
546struct shmctl_args {
547	int shmid;
548	int cmd;
549	struct shmid_ds *buf;
550};
551#endif
552int
553sys_shmctl(struct thread *td, struct shmctl_args *uap)
554{
555	int error = 0;
556	struct shmid_ds buf;
557	size_t bufsz;
558
559	/*
560	 * The only reason IPC_INFO, SHM_INFO, SHM_STAT exists is to support
561	 * Linux binaries.  If we see the call come through the FreeBSD ABI,
562	 * return an error back to the user since we do not to support this.
563	 */
564	if (uap->cmd == IPC_INFO || uap->cmd == SHM_INFO ||
565	    uap->cmd == SHM_STAT)
566		return (EINVAL);
567
568	/* IPC_SET needs to copyin the buffer before calling kern_shmctl */
569	if (uap->cmd == IPC_SET) {
570		if ((error = copyin(uap->buf, &buf, sizeof(struct shmid_ds))))
571			goto done;
572	}
573
574	error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&buf, &bufsz);
575	if (error)
576		goto done;
577
578	/* Cases in which we need to copyout */
579	switch (uap->cmd) {
580	case IPC_STAT:
581		error = copyout(&buf, uap->buf, bufsz);
582		break;
583	}
584
585done:
586	if (error) {
587		/* Invalidate the return value */
588		td->td_retval[0] = -1;
589	}
590	return (error);
591}
592
593
594static int
595shmget_existing(struct thread *td, struct shmget_args *uap, int mode,
596    int segnum)
597{
598	struct shmid_kernel *shmseg;
599#ifdef MAC
600	int error;
601#endif
602
603	SYSVSHM_ASSERT_LOCKED();
604	KASSERT(segnum >= 0 && segnum < shmalloced,
605	    ("segnum %d shmalloced %d", segnum, shmalloced));
606	shmseg = &shmsegs[segnum];
607	if ((uap->shmflg & (IPC_CREAT | IPC_EXCL)) == (IPC_CREAT | IPC_EXCL))
608		return (EEXIST);
609#ifdef MAC
610	error = mac_sysvshm_check_shmget(td->td_ucred, shmseg, uap->shmflg);
611	if (error != 0)
612		return (error);
613#endif
614	if (uap->size != 0 && uap->size > shmseg->u.shm_segsz)
615		return (EINVAL);
616	td->td_retval[0] = IXSEQ_TO_IPCID(segnum, shmseg->u.shm_perm);
617	return (0);
618}
619
620static int
621shmget_allocate_segment(struct thread *td, struct shmget_args *uap, int mode)
622{
623	struct ucred *cred = td->td_ucred;
624	struct shmid_kernel *shmseg;
625	vm_object_t shm_object;
626	int i, segnum;
627	size_t size;
628
629	SYSVSHM_ASSERT_LOCKED();
630
631	if (uap->size < shminfo.shmmin || uap->size > shminfo.shmmax)
632		return (EINVAL);
633	if (shm_nused >= shminfo.shmmni) /* Any shmids left? */
634		return (ENOSPC);
635	size = round_page(uap->size);
636	if (shm_committed + btoc(size) > shminfo.shmall)
637		return (ENOMEM);
638	if (shm_last_free < 0) {
639		shmrealloc();	/* Maybe expand the shmsegs[] array. */
640		for (i = 0; i < shmalloced; i++)
641			if (shmsegs[i].u.shm_perm.mode & SHMSEG_FREE)
642				break;
643		if (i == shmalloced)
644			return (ENOSPC);
645		segnum = i;
646	} else  {
647		segnum = shm_last_free;
648		shm_last_free = -1;
649	}
650	KASSERT(segnum >= 0 && segnum < shmalloced,
651	    ("segnum %d shmalloced %d", segnum, shmalloced));
652	shmseg = &shmsegs[segnum];
653#ifdef RACCT
654	if (racct_enable) {
655		PROC_LOCK(td->td_proc);
656		if (racct_add(td->td_proc, RACCT_NSHM, 1)) {
657			PROC_UNLOCK(td->td_proc);
658			return (ENOSPC);
659		}
660		if (racct_add(td->td_proc, RACCT_SHMSIZE, size)) {
661			racct_sub(td->td_proc, RACCT_NSHM, 1);
662			PROC_UNLOCK(td->td_proc);
663			return (ENOMEM);
664		}
665		PROC_UNLOCK(td->td_proc);
666	}
667#endif
668
669	/*
670	 * We make sure that we have allocated a pager before we need
671	 * to.
672	 */
673	shm_object = vm_pager_allocate(shm_use_phys ? OBJT_PHYS : OBJT_SWAP,
674	    0, size, VM_PROT_DEFAULT, 0, cred);
675	if (shm_object == NULL) {
676#ifdef RACCT
677		if (racct_enable) {
678			PROC_LOCK(td->td_proc);
679			racct_sub(td->td_proc, RACCT_NSHM, 1);
680			racct_sub(td->td_proc, RACCT_SHMSIZE, size);
681			PROC_UNLOCK(td->td_proc);
682		}
683#endif
684		return (ENOMEM);
685	}
686	shm_object->pg_color = 0;
687	VM_OBJECT_WLOCK(shm_object);
688	vm_object_clear_flag(shm_object, OBJ_ONEMAPPING);
689	vm_object_set_flag(shm_object, OBJ_COLORED | OBJ_NOSPLIT);
690	VM_OBJECT_WUNLOCK(shm_object);
691
692	shmseg->object = shm_object;
693	shmseg->u.shm_perm.cuid = shmseg->u.shm_perm.uid = cred->cr_uid;
694	shmseg->u.shm_perm.cgid = shmseg->u.shm_perm.gid = cred->cr_gid;
695	shmseg->u.shm_perm.mode = (mode & ACCESSPERMS) | SHMSEG_ALLOCATED;
696	shmseg->u.shm_perm.key = uap->key;
697	shmseg->u.shm_perm.seq = (shmseg->u.shm_perm.seq + 1) & 0x7fff;
698	shmseg->cred = crhold(cred);
699	shmseg->u.shm_segsz = uap->size;
700	shmseg->u.shm_cpid = td->td_proc->p_pid;
701	shmseg->u.shm_lpid = shmseg->u.shm_nattch = 0;
702	shmseg->u.shm_atime = shmseg->u.shm_dtime = 0;
703#ifdef MAC
704	mac_sysvshm_create(cred, shmseg);
705#endif
706	shmseg->u.shm_ctime = time_second;
707	shm_committed += btoc(size);
708	shm_nused++;
709	td->td_retval[0] = IXSEQ_TO_IPCID(segnum, shmseg->u.shm_perm);
710
711	return (0);
712}
713
714#ifndef _SYS_SYSPROTO_H_
715struct shmget_args {
716	key_t key;
717	size_t size;
718	int shmflg;
719};
720#endif
721int
722sys_shmget(struct thread *td, struct shmget_args *uap)
723{
724	int segnum, mode;
725	int error;
726
727	if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
728		return (ENOSYS);
729	mode = uap->shmflg & ACCESSPERMS;
730	SYSVSHM_LOCK();
731	if (uap->key == IPC_PRIVATE) {
732		error = shmget_allocate_segment(td, uap, mode);
733	} else {
734		segnum = shm_find_segment_by_key(uap->key);
735		if (segnum >= 0)
736			error = shmget_existing(td, uap, mode, segnum);
737		else if ((uap->shmflg & IPC_CREAT) == 0)
738			error = ENOENT;
739		else
740			error = shmget_allocate_segment(td, uap, mode);
741	}
742	SYSVSHM_UNLOCK();
743	return (error);
744}
745
746static void
747shmfork_myhook(struct proc *p1, struct proc *p2)
748{
749	struct shmmap_state *shmmap_s;
750	size_t size;
751	int i;
752
753	SYSVSHM_LOCK();
754	size = shminfo.shmseg * sizeof(struct shmmap_state);
755	shmmap_s = malloc(size, M_SHM, M_WAITOK);
756	bcopy(p1->p_vmspace->vm_shm, shmmap_s, size);
757	p2->p_vmspace->vm_shm = shmmap_s;
758	for (i = 0; i < shminfo.shmseg; i++, shmmap_s++) {
759		if (shmmap_s->shmid != -1) {
760			KASSERT(IPCID_TO_IX(shmmap_s->shmid) >= 0 &&
761			    IPCID_TO_IX(shmmap_s->shmid) < shmalloced,
762			    ("segnum %d shmalloced %d",
763			    IPCID_TO_IX(shmmap_s->shmid), shmalloced));
764			shmsegs[IPCID_TO_IX(shmmap_s->shmid)].u.shm_nattch++;
765		}
766	}
767	SYSVSHM_UNLOCK();
768}
769
770static void
771shmexit_myhook(struct vmspace *vm)
772{
773	struct shmmap_state *base, *shm;
774	int i;
775
776	base = vm->vm_shm;
777	if (base != NULL) {
778		vm->vm_shm = NULL;
779		SYSVSHM_LOCK();
780		for (i = 0, shm = base; i < shminfo.shmseg; i++, shm++) {
781			if (shm->shmid != -1)
782				shm_delete_mapping(vm, shm);
783		}
784		SYSVSHM_UNLOCK();
785		free(base, M_SHM);
786	}
787}
788
789static void
790shmrealloc(void)
791{
792	struct shmid_kernel *newsegs;
793	int i;
794
795	SYSVSHM_ASSERT_LOCKED();
796
797	if (shmalloced >= shminfo.shmmni)
798		return;
799
800	newsegs = malloc(shminfo.shmmni * sizeof(*newsegs), M_SHM, M_WAITOK);
801	for (i = 0; i < shmalloced; i++)
802		bcopy(&shmsegs[i], &newsegs[i], sizeof(newsegs[0]));
803	for (; i < shminfo.shmmni; i++) {
804		shmsegs[i].u.shm_perm.mode = SHMSEG_FREE;
805		shmsegs[i].u.shm_perm.seq = 0;
806#ifdef MAC
807		mac_sysvshm_init(&shmsegs[i]);
808#endif
809	}
810	free(shmsegs, M_SHM);
811	shmsegs = newsegs;
812	shmalloced = shminfo.shmmni;
813}
814
815static struct syscall_helper_data shm_syscalls[] = {
816	SYSCALL_INIT_HELPER(shmat),
817	SYSCALL_INIT_HELPER(shmctl),
818	SYSCALL_INIT_HELPER(shmdt),
819	SYSCALL_INIT_HELPER(shmget),
820#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
821    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
822	SYSCALL_INIT_HELPER_COMPAT(freebsd7_shmctl),
823#endif
824#if defined(__i386__) && (defined(COMPAT_FREEBSD4) || defined(COMPAT_43))
825	SYSCALL_INIT_HELPER(shmsys),
826#endif
827	SYSCALL_INIT_LAST
828};
829
830#ifdef COMPAT_FREEBSD32
831#include <compat/freebsd32/freebsd32.h>
832#include <compat/freebsd32/freebsd32_ipc.h>
833#include <compat/freebsd32/freebsd32_proto.h>
834#include <compat/freebsd32/freebsd32_signal.h>
835#include <compat/freebsd32/freebsd32_syscall.h>
836#include <compat/freebsd32/freebsd32_util.h>
837
838static struct syscall_helper_data shm32_syscalls[] = {
839	SYSCALL32_INIT_HELPER_COMPAT(shmat),
840	SYSCALL32_INIT_HELPER_COMPAT(shmdt),
841	SYSCALL32_INIT_HELPER_COMPAT(shmget),
842	SYSCALL32_INIT_HELPER(freebsd32_shmsys),
843	SYSCALL32_INIT_HELPER(freebsd32_shmctl),
844#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
845    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
846	SYSCALL32_INIT_HELPER(freebsd7_freebsd32_shmctl),
847#endif
848	SYSCALL_INIT_LAST
849};
850#endif
851
852static int
853shminit(void)
854{
855	int i, error;
856
857#ifndef BURN_BRIDGES
858	if (TUNABLE_ULONG_FETCH("kern.ipc.shmmaxpgs", &shminfo.shmall) != 0)
859		printf("kern.ipc.shmmaxpgs is now called kern.ipc.shmall!\n");
860#endif
861	TUNABLE_ULONG_FETCH("kern.ipc.shmall", &shminfo.shmall);
862	if (!TUNABLE_ULONG_FETCH("kern.ipc.shmmax", &shminfo.shmmax)) {
863		/* Initialize shmmax dealing with possible overflow. */
864		for (i = PAGE_SIZE; i > 0; i--) {
865			shminfo.shmmax = shminfo.shmall * i;
866			if (shminfo.shmmax >= shminfo.shmall)
867				break;
868		}
869	}
870	TUNABLE_ULONG_FETCH("kern.ipc.shmmin", &shminfo.shmmin);
871	TUNABLE_ULONG_FETCH("kern.ipc.shmmni", &shminfo.shmmni);
872	TUNABLE_ULONG_FETCH("kern.ipc.shmseg", &shminfo.shmseg);
873	TUNABLE_INT_FETCH("kern.ipc.shm_use_phys", &shm_use_phys);
874
875	shmalloced = shminfo.shmmni;
876	shmsegs = malloc(shmalloced * sizeof(shmsegs[0]), M_SHM, M_WAITOK);
877	for (i = 0; i < shmalloced; i++) {
878		shmsegs[i].u.shm_perm.mode = SHMSEG_FREE;
879		shmsegs[i].u.shm_perm.seq = 0;
880#ifdef MAC
881		mac_sysvshm_init(&shmsegs[i]);
882#endif
883	}
884	shm_last_free = 0;
885	shm_nused = 0;
886	shm_committed = 0;
887	sx_init(&sysvshmsx, "sysvshmsx");
888	shmexit_hook = &shmexit_myhook;
889	shmfork_hook = &shmfork_myhook;
890
891	error = syscall_helper_register(shm_syscalls);
892	if (error != 0)
893		return (error);
894#ifdef COMPAT_FREEBSD32
895	error = syscall32_helper_register(shm32_syscalls);
896	if (error != 0)
897		return (error);
898#endif
899	return (0);
900}
901
902static int
903shmunload(void)
904{
905	int i;
906
907	if (shm_nused > 0)
908		return (EBUSY);
909
910#ifdef COMPAT_FREEBSD32
911	syscall32_helper_unregister(shm32_syscalls);
912#endif
913	syscall_helper_unregister(shm_syscalls);
914
915	for (i = 0; i < shmalloced; i++) {
916#ifdef MAC
917		mac_sysvshm_destroy(&shmsegs[i]);
918#endif
919		/*
920		 * Objects might be still mapped into the processes
921		 * address spaces.  Actual free would happen on the
922		 * last mapping destruction.
923		 */
924		if (shmsegs[i].u.shm_perm.mode != SHMSEG_FREE)
925			vm_object_deallocate(shmsegs[i].object);
926	}
927	free(shmsegs, M_SHM);
928	shmexit_hook = NULL;
929	shmfork_hook = NULL;
930	sx_destroy(&sysvshmsx);
931	return (0);
932}
933
934static int
935sysctl_shmsegs(SYSCTL_HANDLER_ARGS)
936{
937	int error;
938
939	SYSVSHM_LOCK();
940	error = SYSCTL_OUT(req, shmsegs, shmalloced * sizeof(shmsegs[0]));
941	SYSVSHM_UNLOCK();
942	return (error);
943}
944
945#if defined(__i386__) && (defined(COMPAT_FREEBSD4) || defined(COMPAT_43))
946struct oshmid_ds {
947	struct	ipc_perm_old shm_perm;	/* operation perms */
948	int	shm_segsz;		/* size of segment (bytes) */
949	u_short	shm_cpid;		/* pid, creator */
950	u_short	shm_lpid;		/* pid, last operation */
951	short	shm_nattch;		/* no. of current attaches */
952	time_t	shm_atime;		/* last attach time */
953	time_t	shm_dtime;		/* last detach time */
954	time_t	shm_ctime;		/* last change time */
955	void	*shm_handle;		/* internal handle for shm segment */
956};
957
958struct oshmctl_args {
959	int shmid;
960	int cmd;
961	struct oshmid_ds *ubuf;
962};
963
964static int
965oshmctl(struct thread *td, struct oshmctl_args *uap)
966{
967#ifdef COMPAT_43
968	int error = 0;
969	struct shmid_kernel *shmseg;
970	struct oshmid_ds outbuf;
971
972	if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
973		return (ENOSYS);
974	if (uap->cmd != IPC_STAT) {
975		return (freebsd7_shmctl(td,
976		    (struct freebsd7_shmctl_args *)uap));
977	}
978	SYSVSHM_LOCK();
979	shmseg = shm_find_segment(uap->shmid, true);
980	if (shmseg == NULL) {
981		SYSVSHM_UNLOCK();
982		return (EINVAL);
983	}
984	error = ipcperm(td, &shmseg->u.shm_perm, IPC_R);
985	if (error != 0) {
986		SYSVSHM_UNLOCK();
987		return (error);
988	}
989#ifdef MAC
990	error = mac_sysvshm_check_shmctl(td->td_ucred, shmseg, uap->cmd);
991	if (error != 0) {
992		SYSVSHM_UNLOCK();
993		return (error);
994	}
995#endif
996	ipcperm_new2old(&shmseg->u.shm_perm, &outbuf.shm_perm);
997	outbuf.shm_segsz = shmseg->u.shm_segsz;
998	outbuf.shm_cpid = shmseg->u.shm_cpid;
999	outbuf.shm_lpid = shmseg->u.shm_lpid;
1000	outbuf.shm_nattch = shmseg->u.shm_nattch;
1001	outbuf.shm_atime = shmseg->u.shm_atime;
1002	outbuf.shm_dtime = shmseg->u.shm_dtime;
1003	outbuf.shm_ctime = shmseg->u.shm_ctime;
1004	outbuf.shm_handle = shmseg->object;
1005	SYSVSHM_UNLOCK();
1006	error = copyout(&outbuf, uap->ubuf, sizeof(outbuf));
1007	return (error);
1008#else
1009	return (EINVAL);
1010#endif
1011}
1012
1013/* XXX casting to (sy_call_t *) is bogus, as usual. */
1014static sy_call_t *shmcalls[] = {
1015	(sy_call_t *)sys_shmat, (sy_call_t *)oshmctl,
1016	(sy_call_t *)sys_shmdt, (sy_call_t *)sys_shmget,
1017	(sy_call_t *)freebsd7_shmctl
1018};
1019
1020#ifndef _SYS_SYSPROTO_H_
1021/* XXX actually varargs. */
1022struct shmsys_args {
1023	int	which;
1024	int	a2;
1025	int	a3;
1026	int	a4;
1027};
1028#endif
1029int
1030sys_shmsys(struct thread *td, struct shmsys_args *uap)
1031{
1032	int error;
1033
1034	if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
1035		return (ENOSYS);
1036	if (uap->which < 0 || uap->which >= nitems(shmcalls))
1037		return (EINVAL);
1038	error = (*shmcalls[uap->which])(td, &uap->a2);
1039	return (error);
1040}
1041
1042#endif	/* i386 && (COMPAT_FREEBSD4 || COMPAT_43) */
1043
1044#ifdef COMPAT_FREEBSD32
1045
1046int
1047freebsd32_shmsys(struct thread *td, struct freebsd32_shmsys_args *uap)
1048{
1049
1050#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1051    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1052	switch (uap->which) {
1053	case 0:	{	/* shmat */
1054		struct shmat_args ap;
1055
1056		ap.shmid = uap->a2;
1057		ap.shmaddr = PTRIN(uap->a3);
1058		ap.shmflg = uap->a4;
1059		return (sysent[SYS_shmat].sy_call(td, &ap));
1060	}
1061	case 2: {	/* shmdt */
1062		struct shmdt_args ap;
1063
1064		ap.shmaddr = PTRIN(uap->a2);
1065		return (sysent[SYS_shmdt].sy_call(td, &ap));
1066	}
1067	case 3: {	/* shmget */
1068		struct shmget_args ap;
1069
1070		ap.key = uap->a2;
1071		ap.size = uap->a3;
1072		ap.shmflg = uap->a4;
1073		return (sysent[SYS_shmget].sy_call(td, &ap));
1074	}
1075	case 4: {	/* shmctl */
1076		struct freebsd7_freebsd32_shmctl_args ap;
1077
1078		ap.shmid = uap->a2;
1079		ap.cmd = uap->a3;
1080		ap.buf = PTRIN(uap->a4);
1081		return (freebsd7_freebsd32_shmctl(td, &ap));
1082	}
1083	case 1:		/* oshmctl */
1084	default:
1085		return (EINVAL);
1086	}
1087#else
1088	return (nosys(td, NULL));
1089#endif
1090}
1091
1092#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1093    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1094int
1095freebsd7_freebsd32_shmctl(struct thread *td,
1096    struct freebsd7_freebsd32_shmctl_args *uap)
1097{
1098	int error = 0;
1099	union {
1100		struct shmid_ds shmid_ds;
1101		struct shm_info shm_info;
1102		struct shminfo shminfo;
1103	} u;
1104	union {
1105		struct shmid_ds32_old shmid_ds32;
1106		struct shm_info32 shm_info32;
1107		struct shminfo32 shminfo32;
1108	} u32;
1109	size_t sz;
1110
1111	if (uap->cmd == IPC_SET) {
1112		if ((error = copyin(uap->buf, &u32.shmid_ds32,
1113		    sizeof(u32.shmid_ds32))))
1114			goto done;
1115		freebsd32_ipcperm_old_in(&u32.shmid_ds32.shm_perm,
1116		    &u.shmid_ds.shm_perm);
1117		CP(u32.shmid_ds32, u.shmid_ds, shm_segsz);
1118		CP(u32.shmid_ds32, u.shmid_ds, shm_lpid);
1119		CP(u32.shmid_ds32, u.shmid_ds, shm_cpid);
1120		CP(u32.shmid_ds32, u.shmid_ds, shm_nattch);
1121		CP(u32.shmid_ds32, u.shmid_ds, shm_atime);
1122		CP(u32.shmid_ds32, u.shmid_ds, shm_dtime);
1123		CP(u32.shmid_ds32, u.shmid_ds, shm_ctime);
1124	}
1125
1126	error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&u, &sz);
1127	if (error)
1128		goto done;
1129
1130	/* Cases in which we need to copyout */
1131	switch (uap->cmd) {
1132	case IPC_INFO:
1133		CP(u.shminfo, u32.shminfo32, shmmax);
1134		CP(u.shminfo, u32.shminfo32, shmmin);
1135		CP(u.shminfo, u32.shminfo32, shmmni);
1136		CP(u.shminfo, u32.shminfo32, shmseg);
1137		CP(u.shminfo, u32.shminfo32, shmall);
1138		error = copyout(&u32.shminfo32, uap->buf,
1139		    sizeof(u32.shminfo32));
1140		break;
1141	case SHM_INFO:
1142		CP(u.shm_info, u32.shm_info32, used_ids);
1143		CP(u.shm_info, u32.shm_info32, shm_rss);
1144		CP(u.shm_info, u32.shm_info32, shm_tot);
1145		CP(u.shm_info, u32.shm_info32, shm_swp);
1146		CP(u.shm_info, u32.shm_info32, swap_attempts);
1147		CP(u.shm_info, u32.shm_info32, swap_successes);
1148		error = copyout(&u32.shm_info32, uap->buf,
1149		    sizeof(u32.shm_info32));
1150		break;
1151	case SHM_STAT:
1152	case IPC_STAT:
1153		freebsd32_ipcperm_old_out(&u.shmid_ds.shm_perm,
1154		    &u32.shmid_ds32.shm_perm);
1155		if (u.shmid_ds.shm_segsz > INT32_MAX)
1156			u32.shmid_ds32.shm_segsz = INT32_MAX;
1157		else
1158			CP(u.shmid_ds, u32.shmid_ds32, shm_segsz);
1159		CP(u.shmid_ds, u32.shmid_ds32, shm_lpid);
1160		CP(u.shmid_ds, u32.shmid_ds32, shm_cpid);
1161		CP(u.shmid_ds, u32.shmid_ds32, shm_nattch);
1162		CP(u.shmid_ds, u32.shmid_ds32, shm_atime);
1163		CP(u.shmid_ds, u32.shmid_ds32, shm_dtime);
1164		CP(u.shmid_ds, u32.shmid_ds32, shm_ctime);
1165		u32.shmid_ds32.shm_internal = 0;
1166		error = copyout(&u32.shmid_ds32, uap->buf,
1167		    sizeof(u32.shmid_ds32));
1168		break;
1169	}
1170
1171done:
1172	if (error) {
1173		/* Invalidate the return value */
1174		td->td_retval[0] = -1;
1175	}
1176	return (error);
1177}
1178#endif
1179
1180int
1181freebsd32_shmctl(struct thread *td, struct freebsd32_shmctl_args *uap)
1182{
1183	int error = 0;
1184	union {
1185		struct shmid_ds shmid_ds;
1186		struct shm_info shm_info;
1187		struct shminfo shminfo;
1188	} u;
1189	union {
1190		struct shmid_ds32 shmid_ds32;
1191		struct shm_info32 shm_info32;
1192		struct shminfo32 shminfo32;
1193	} u32;
1194	size_t sz;
1195
1196	if (uap->cmd == IPC_SET) {
1197		if ((error = copyin(uap->buf, &u32.shmid_ds32,
1198		    sizeof(u32.shmid_ds32))))
1199			goto done;
1200		freebsd32_ipcperm_in(&u32.shmid_ds32.shm_perm,
1201		    &u.shmid_ds.shm_perm);
1202		CP(u32.shmid_ds32, u.shmid_ds, shm_segsz);
1203		CP(u32.shmid_ds32, u.shmid_ds, shm_lpid);
1204		CP(u32.shmid_ds32, u.shmid_ds, shm_cpid);
1205		CP(u32.shmid_ds32, u.shmid_ds, shm_nattch);
1206		CP(u32.shmid_ds32, u.shmid_ds, shm_atime);
1207		CP(u32.shmid_ds32, u.shmid_ds, shm_dtime);
1208		CP(u32.shmid_ds32, u.shmid_ds, shm_ctime);
1209	}
1210
1211	error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&u, &sz);
1212	if (error)
1213		goto done;
1214
1215	/* Cases in which we need to copyout */
1216	switch (uap->cmd) {
1217	case IPC_INFO:
1218		CP(u.shminfo, u32.shminfo32, shmmax);
1219		CP(u.shminfo, u32.shminfo32, shmmin);
1220		CP(u.shminfo, u32.shminfo32, shmmni);
1221		CP(u.shminfo, u32.shminfo32, shmseg);
1222		CP(u.shminfo, u32.shminfo32, shmall);
1223		error = copyout(&u32.shminfo32, uap->buf,
1224		    sizeof(u32.shminfo32));
1225		break;
1226	case SHM_INFO:
1227		CP(u.shm_info, u32.shm_info32, used_ids);
1228		CP(u.shm_info, u32.shm_info32, shm_rss);
1229		CP(u.shm_info, u32.shm_info32, shm_tot);
1230		CP(u.shm_info, u32.shm_info32, shm_swp);
1231		CP(u.shm_info, u32.shm_info32, swap_attempts);
1232		CP(u.shm_info, u32.shm_info32, swap_successes);
1233		error = copyout(&u32.shm_info32, uap->buf,
1234		    sizeof(u32.shm_info32));
1235		break;
1236	case SHM_STAT:
1237	case IPC_STAT:
1238		freebsd32_ipcperm_out(&u.shmid_ds.shm_perm,
1239		    &u32.shmid_ds32.shm_perm);
1240		if (u.shmid_ds.shm_segsz > INT32_MAX)
1241			u32.shmid_ds32.shm_segsz = INT32_MAX;
1242		else
1243			CP(u.shmid_ds, u32.shmid_ds32, shm_segsz);
1244		CP(u.shmid_ds, u32.shmid_ds32, shm_lpid);
1245		CP(u.shmid_ds, u32.shmid_ds32, shm_cpid);
1246		CP(u.shmid_ds, u32.shmid_ds32, shm_nattch);
1247		CP(u.shmid_ds, u32.shmid_ds32, shm_atime);
1248		CP(u.shmid_ds, u32.shmid_ds32, shm_dtime);
1249		CP(u.shmid_ds, u32.shmid_ds32, shm_ctime);
1250		error = copyout(&u32.shmid_ds32, uap->buf,
1251		    sizeof(u32.shmid_ds32));
1252		break;
1253	}
1254
1255done:
1256	if (error) {
1257		/* Invalidate the return value */
1258		td->td_retval[0] = -1;
1259	}
1260	return (error);
1261}
1262#endif
1263
1264#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1265    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1266
1267#ifndef CP
1268#define CP(src, dst, fld)	do { (dst).fld = (src).fld; } while (0)
1269#endif
1270
1271#ifndef _SYS_SYSPROTO_H_
1272struct freebsd7_shmctl_args {
1273	int shmid;
1274	int cmd;
1275	struct shmid_ds_old *buf;
1276};
1277#endif
1278int
1279freebsd7_shmctl(struct thread *td, struct freebsd7_shmctl_args *uap)
1280{
1281	int error = 0;
1282	struct shmid_ds_old old;
1283	struct shmid_ds buf;
1284	size_t bufsz;
1285
1286	/*
1287	 * The only reason IPC_INFO, SHM_INFO, SHM_STAT exists is to support
1288	 * Linux binaries.  If we see the call come through the FreeBSD ABI,
1289	 * return an error back to the user since we do not to support this.
1290	 */
1291	if (uap->cmd == IPC_INFO || uap->cmd == SHM_INFO ||
1292	    uap->cmd == SHM_STAT)
1293		return (EINVAL);
1294
1295	/* IPC_SET needs to copyin the buffer before calling kern_shmctl */
1296	if (uap->cmd == IPC_SET) {
1297		if ((error = copyin(uap->buf, &old, sizeof(old))))
1298			goto done;
1299		ipcperm_old2new(&old.shm_perm, &buf.shm_perm);
1300		CP(old, buf, shm_segsz);
1301		CP(old, buf, shm_lpid);
1302		CP(old, buf, shm_cpid);
1303		CP(old, buf, shm_nattch);
1304		CP(old, buf, shm_atime);
1305		CP(old, buf, shm_dtime);
1306		CP(old, buf, shm_ctime);
1307	}
1308
1309	error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&buf, &bufsz);
1310	if (error)
1311		goto done;
1312
1313	/* Cases in which we need to copyout */
1314	switch (uap->cmd) {
1315	case IPC_STAT:
1316		ipcperm_new2old(&buf.shm_perm, &old.shm_perm);
1317		if (buf.shm_segsz > INT_MAX)
1318			old.shm_segsz = INT_MAX;
1319		else
1320			CP(buf, old, shm_segsz);
1321		CP(buf, old, shm_lpid);
1322		CP(buf, old, shm_cpid);
1323		if (buf.shm_nattch > SHRT_MAX)
1324			old.shm_nattch = SHRT_MAX;
1325		else
1326			CP(buf, old, shm_nattch);
1327		CP(buf, old, shm_atime);
1328		CP(buf, old, shm_dtime);
1329		CP(buf, old, shm_ctime);
1330		old.shm_internal = NULL;
1331		error = copyout(&old, uap->buf, sizeof(old));
1332		break;
1333	}
1334
1335done:
1336	if (error) {
1337		/* Invalidate the return value */
1338		td->td_retval[0] = -1;
1339	}
1340	return (error);
1341}
1342
1343#endif	/* COMPAT_FREEBSD4 || COMPAT_FREEBSD5 || COMPAT_FREEBSD6 ||
1344	   COMPAT_FREEBSD7 */
1345
1346static int
1347sysvshm_modload(struct module *module, int cmd, void *arg)
1348{
1349	int error = 0;
1350
1351	switch (cmd) {
1352	case MOD_LOAD:
1353		error = shminit();
1354		if (error != 0)
1355			shmunload();
1356		break;
1357	case MOD_UNLOAD:
1358		error = shmunload();
1359		break;
1360	case MOD_SHUTDOWN:
1361		break;
1362	default:
1363		error = EINVAL;
1364		break;
1365	}
1366	return (error);
1367}
1368
1369static moduledata_t sysvshm_mod = {
1370	"sysvshm",
1371	&sysvshm_modload,
1372	NULL
1373};
1374
1375DECLARE_MODULE(sysvshm, sysvshm_mod, SI_SUB_SYSV_SHM, SI_ORDER_FIRST);
1376MODULE_VERSION(sysvshm, 1);
1377