1 /*
2 * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /*
29 * Copyright (c) 1990, 1996-1998 Apple Computer, Inc.
30 * All Rights Reserved.
31 */
32 /*
33 * posix_sem.c : Support for POSIX semaphore APIs
34 *
35 * File: posix_sem.c
36 * Author: Ananthakrishna Ramesh
37 *
38 * HISTORY
39 * 2-Sep-1999 A.Ramesh
40 * Created for MacOSX
41 *
42 */
43 /*
44 * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
45 * support for mandatory and extensible security protections. This notice
46 * is included in support of clause 2.2 (b) of the Apple Public License,
47 * Version 2.0.
48 */
49
50 #include <sys/cdefs.h>
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/kernel.h>
54 #include <sys/file_internal.h>
55 #include <sys/filedesc.h>
56 #include <sys/stat.h>
57 #include <sys/proc_internal.h>
58 #include <sys/kauth.h>
59 #include <sys/mount.h>
60 #include <sys/namei.h>
61 #include <sys/vnode.h>
62 #include <sys/ioctl.h>
63 #include <sys/tty.h>
64 #include <sys/malloc.h>
65 #include <sys/semaphore.h>
66 #include <sys/sysproto.h>
67 #include <sys/proc_info.h>
68 #include <sys/random.h>
69 #include <net/siphash.h>
70
71 #if CONFIG_MACF
72 #include <sys/vnode_internal.h>
73 #include <security/mac_framework.h>
74 #endif
75
76 #include <security/audit/audit.h>
77
78 #include <mach/mach_types.h>
79 #include <mach/vm_prot.h>
80 #include <mach/semaphore.h>
81 #include <mach/sync_policy.h>
82 #include <mach/task.h>
83 #include <kern/kern_types.h>
84 #include <kern/task.h>
85 #include <kern/clock.h>
86 #include <mach/kern_return.h>
87
88 #define f_flag fp_glob->fg_flag
89 #define f_ops fp_glob->fg_ops
90
91 #define PSEMNAMLEN 31 /* maximum name segment length we bother with */
92 #define PSEMTEAMIDLEN 31 /* maximum length of team ID we consider */
93
94 struct pseminfo {
95 unsigned int psem_flags;
96 unsigned int psem_usecount;
97 mode_t psem_mode;
98 uid_t psem_uid;
99 gid_t psem_gid;
100 char psem_name[PSEMNAMLEN + 1]; /* segment name */
101 semaphore_t psem_semobject;
102 struct label * psem_label;
103 pid_t psem_creator_pid;
104 uint64_t psem_creator_uniqueid;
105 };
106 #define PSEMINFO_NULL (struct pseminfo *)0
107
108 #define PSEM_NONE 1
109 #define PSEM_DEFINED 2
110 #define PSEM_ALLOCATED 4
111 #define PSEM_MAPPED 8
112 #define PSEM_INUSE 0x10
113 #define PSEM_REMOVED 0x20
114 #define PSEM_INCREATE 0x40
115 #define PSEM_INDELETE 0x80
116
117 struct psemcache {
118 LIST_ENTRY(psemcache) psem_hash; /* hash chain */
119 struct pseminfo *pseminfo; /* vnode the name refers to */
120 size_t psem_nlen; /* length of name */
121 size_t psem_teamidlen; /* length of team ID */
122 char psem_name[PSEMNAMLEN + 1]; /* segment name */
123 char psem_teamid[PSEMTEAMIDLEN + 1]; /* team ID of users, if any */
124 };
125 #define PSEMCACHE_NULL (struct psemcache *)0
126
127 #define PSEMCACHE_NOTFOUND (0)
128 #define PSEMCACHE_FOUND (-1)
129 #define PSEMCACHE_NEGATIVE (ENOENT)
130
131 struct psemstats {
132 long pstats_hits;
133 long pstats_miss;
134 long pstats_local_hits;
135 long pstats_global_hits;
136 long pstats_local_miss;
137 long pstats_global_miss;
138 long pstats_local_collisions;
139 long pstats_global_collisions;
140 long pstats_fallback_hits; /* hits that missed local but hit global */
141 long pstats_fallback_miss; /* hits that missed both local and global */
142 long pstats_neghits; /* hits to 'negative entries' (return ENOENT) */
143 long pstats_longnames; /* semaphore or team ID ENAMETOOLONG */
144 };
145
146 struct psemname {
147 char *psem_nameptr; /* pointer to looked up name */
148 size_t psem_namelen; /* length of looked up component */
149 uint64_t psem_hash_local; /* hash value of looked up name and team */
150 uint64_t psem_hash_global; /* hash value of looked up name, without team */
151 const char *psem_teamidptr;
152 size_t psem_teamidlen;
153 };
154
155 struct psemnode {
156 struct pseminfo *pinfo;
157 #if DIAGNOSTIC
158 unsigned int readcnt;
159 unsigned int writecnt;
160 #endif
161 };
162 #define PSEMNODE_NULL (struct psemnode *)0
163
164 LIST_HEAD(psemhashhead, psemcache);
165
166 struct psemhashtable {
167 struct psemhashhead *psem_table;
168
169 /* Hash table mask, i.e size - 1 */
170 u_long psem_table_mask;
171
172 /* SipHash key, randomly assigned at boot */
173 uint8_t psem_siphash_key[SIPHASH_KEY_LENGTH];
174 };
175 #define PSEMHASH(table, hash) (&(table).psem_table[(hash) & (table).psem_table_mask])
176
177 struct psemhashtable psem_global, psem_local;
178
179 long posix_sem_num; /* number of POSIX semaphores on the system */
180 long posix_sem_max = 10000; /* max number of POSIX semaphores on the system */
181
182 SYSCTL_NODE(_kern, KERN_POSIX, posix, CTLFLAG_RW | CTLFLAG_LOCKED, 0, "Posix");
183 SYSCTL_NODE(_kern_posix, OID_AUTO, sem, CTLFLAG_RW | CTLFLAG_LOCKED, 0, "Semaphores");
184 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, max, CTLFLAG_RW | CTLFLAG_LOCKED, &posix_sem_max, "max");
185
186 struct psemstats psemstats; /* cache effectiveness statistics */
187
188 #if DEBUG || DEVELOPMENT
189 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, hits, CTLFLAG_RD, &psemstats.pstats_hits, "");
190 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, miss, CTLFLAG_RD, &psemstats.pstats_miss, "");
191 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, local_hits, CTLFLAG_RD, &psemstats.pstats_local_hits, "");
192 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, local_miss, CTLFLAG_RD, &psemstats.pstats_local_miss, "");
193 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, global_hits, CTLFLAG_RD, &psemstats.pstats_global_hits, "");
194 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, global_miss, CTLFLAG_RD, &psemstats.pstats_global_miss, "");
195 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, fallback_hits, CTLFLAG_RD, &psemstats.pstats_fallback_hits, "");
196 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, fallback_miss, CTLFLAG_RD, &psemstats.pstats_fallback_miss, "");
197 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, local_collisions, CTLFLAG_RD, &psemstats.pstats_local_collisions, "");
198 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, global_collisions, CTLFLAG_RD, &psemstats.pstats_global_collisions, "");
199 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, neghits, CTLFLAG_RD, &psemstats.pstats_neghits, "");
200 SYSCTL_LONG(_kern_posix_sem, OID_AUTO, longnames, CTLFLAG_RD, &psemstats.pstats_longnames, "");
201 #endif
202
203 static int psem_access(struct pseminfo *pinfo, mode_t mode, kauth_cred_t cred);
204 static int psem_cache_search(struct pseminfo **,
205 struct psemname *, struct psemcache **);
206 static int psem_delete(struct pseminfo * pinfo);
207
208 static int psem_closefile(struct fileglob *fp, vfs_context_t ctx);
209 static int psem_unlink_internal(struct pseminfo *pinfo, struct psemcache *pcache);
210
211 static const char *psem_get_teamid(proc_t p);
212
213 static const struct fileops psemops = {
214 .fo_type = DTYPE_PSXSEM,
215 .fo_read = fo_no_read,
216 .fo_write = fo_no_write,
217 .fo_ioctl = fo_no_ioctl,
218 .fo_select = fo_no_select,
219 .fo_close = psem_closefile,
220 .fo_drain = fo_no_drain,
221 .fo_kqfilter = fo_no_kqfilter,
222 };
223
224 static LCK_GRP_DECLARE(psx_sem_subsys_lck_grp, "posix semaphores");
225 static LCK_MTX_DECLARE(psx_sem_subsys_mutex, &psx_sem_subsys_lck_grp);
226
227 #define PSEM_SUBSYS_LOCK() lck_mtx_lock(&psx_sem_subsys_mutex)
228 #define PSEM_SUBSYS_UNLOCK() lck_mtx_unlock(&psx_sem_subsys_mutex)
229 #define PSEM_SUBSYS_ASSERT_HELD() LCK_MTX_ASSERT(&psx_sem_subsys_mutex, LCK_MTX_ASSERT_OWNED)
230
231
232 static int psem_cache_add(struct pseminfo *psemp, struct psemname *pnp, struct psemcache *pcp);
233 static void psem_cache_delete(struct psemcache *pcp);
234 int psem_cache_purge_all(void);
235
236 static struct psemname
psem_cache_hash(char * name,size_t len,const char * teamid,size_t teamidlen)237 psem_cache_hash(char *name, size_t len, const char *teamid, size_t teamidlen)
238 {
239 SIPHASH_CTX ctx;
240 struct psemname nd;
241
242 nd.psem_nameptr = name;
243 nd.psem_namelen = len;
244 nd.psem_teamidptr = teamid;
245 nd.psem_teamidlen = teamidlen;
246 nd.psem_hash_local = 0;
247 nd.psem_hash_global = 0;
248
249 _Static_assert(sizeof(nd.psem_hash_local) == SIPHASH_DIGEST_LENGTH, "hash field is wrong size for SipHash");
250 _Static_assert(sizeof(nd.psem_hash_global) == SIPHASH_DIGEST_LENGTH, "hash field is wrong size for SipHash");
251
252 /*
253 * This routine is called before taking the subsystem lock, so we'll prepare hashes
254 * for both global and local tables up front.
255 */
256 SipHash24_Init(&ctx);
257 SipHash_SetKey(&ctx, psem_global.psem_siphash_key);
258 SipHash_Update(&ctx, name, len);
259 SipHash_Final((u_int8_t *)&nd.psem_hash_global, &ctx);
260
261 if (teamidlen > 0) {
262 SipHash24_Init(&ctx);
263 SipHash_SetKey(&ctx, psem_local.psem_siphash_key);
264 SipHash_Update(&ctx, name, len);
265 SipHash_Update(&ctx, teamid, teamidlen);
266 SipHash_Final((u_int8_t *)&nd.psem_hash_local, &ctx);
267 }
268
269 return nd;
270 }
271
272 /*
273 * Returns 1 if the semaphore name matches what we're looking for, otherwise 0.
274 * When searching the local table, the team ID must match too.
275 */
276 static int
psem_cache_is_match(struct psemcache * sem,struct psemname * target,bool local)277 psem_cache_is_match(struct psemcache *sem, struct psemname *target, bool local)
278 {
279 bool name_matches = target->psem_namelen == sem->psem_nlen &&
280 !bcmp(target->psem_nameptr, sem->psem_name, target->psem_namelen);
281
282 if (local) {
283 bool teamid_matches = target->psem_teamidlen == sem->psem_teamidlen &&
284 !bcmp(target->psem_teamidptr, sem->psem_teamid, target->psem_teamidlen);
285 return name_matches && teamid_matches;
286 }
287
288 return name_matches;
289 }
290
291 /*
292 * Lookup an entry in the cache
293 *
294 *
295 * status of -1 is returned if matches
296 * If the lookup determines that the name does not exist
297 * (negative cacheing), a status of ENOENT is returned. If the lookup
298 * fails, a status of zero is returned.
299 */
300
301 static int
psem_cache_search(struct pseminfo ** psemp,struct psemname * pnp,struct psemcache ** pcache)302 psem_cache_search(struct pseminfo **psemp, struct psemname *pnp,
303 struct psemcache **pcache)
304 {
305 struct psemcache *pcp = NULL, *nnp;
306 struct psemhashhead *pcpp;
307
308 if (pnp->psem_namelen > PSEMNAMLEN || pnp->psem_teamidlen > PSEMTEAMIDLEN) {
309 os_atomic_inc(&psemstats.pstats_longnames, relaxed);
310 return PSEMCACHE_NOTFOUND;
311 }
312
313 /* If Team ID is present, try to look up in the local table first. */
314 if (pnp->psem_teamidlen > 0) {
315 pcpp = PSEMHASH(psem_local, pnp->psem_hash_local);
316
317 for (pcp = pcpp->lh_first; pcp != 0; pcp = nnp) {
318 nnp = pcp->psem_hash.le_next;
319 if (psem_cache_is_match(pcp, pnp, true)) {
320 break;
321 }
322 os_atomic_inc(&psemstats.pstats_local_collisions, relaxed);
323 }
324
325 if (pcp == 0) {
326 os_atomic_inc(&psemstats.pstats_local_miss, relaxed);
327 } else {
328 os_atomic_inc(&psemstats.pstats_local_hits, relaxed);
329 }
330 }
331
332 /* Otherwise, or if the local lookup failed, search the global table. */
333 if (pcp == 0) {
334 pcpp = PSEMHASH(psem_global, pnp->psem_hash_global);
335
336 for (pcp = pcpp->lh_first; pcp != 0; pcp = nnp) {
337 nnp = pcp->psem_hash.le_next;
338 if (psem_cache_is_match(pcp, pnp, false)) {
339 break;
340 }
341 os_atomic_inc(&psemstats.pstats_global_collisions, relaxed);
342 }
343
344 if (pcp == 0) {
345 os_atomic_inc(&psemstats.pstats_global_miss, relaxed);
346 if (pnp->psem_teamidlen > 0) {
347 os_atomic_inc(&psemstats.pstats_fallback_miss, relaxed);
348 }
349 } else {
350 os_atomic_inc(&psemstats.pstats_global_hits, relaxed);
351 if (pnp->psem_teamidlen > 0) {
352 os_atomic_inc(&psemstats.pstats_fallback_hits, relaxed);
353 }
354 }
355 }
356
357 if (pcp == 0) {
358 os_atomic_inc(&psemstats.pstats_miss, relaxed);
359 return PSEMCACHE_NOTFOUND;
360 }
361
362 /* We found a "positive" match, return the vnode */
363 if (pcp->pseminfo) {
364 os_atomic_inc(&psemstats.pstats_hits, relaxed);
365 /* TOUCH(ncp); */
366 *psemp = pcp->pseminfo;
367 *pcache = pcp;
368 return PSEMCACHE_FOUND;
369 }
370
371 /*
372 * We found a "negative" match, ENOENT notifies client of this match.
373 * The nc_vpid field records whether this is a whiteout.
374 */
375 os_atomic_inc(&psemstats.pstats_neghits, relaxed);
376 return PSEMCACHE_NEGATIVE;
377 }
378
379 /*
380 * Add an entry to the cache.
381 */
382 static int
psem_cache_add(struct pseminfo * psemp,struct psemname * pnp,struct psemcache * pcp)383 psem_cache_add(struct pseminfo *psemp, struct psemname *pnp, struct psemcache *pcp)
384 {
385 struct psemhashhead *pcpp;
386
387 #if DIAGNOSTIC
388 if (pnp->psem_namelen > PSEMNAMLEN) {
389 panic("cache_enter: name too long");
390 }
391 if (pnp->psem_teamidlen > PSEMTEAMIDLEN) {
392 panic("cache_enter: teamid too long");
393 }
394 #endif
395
396 if (posix_sem_num >= posix_sem_max) {
397 return ENOSPC;
398 }
399 posix_sem_num++;
400 /*
401 * Fill in cache info, if vp is NULL this is a "negative" cache entry.
402 * For negative entries, we have to record whether it is a whiteout.
403 * the whiteout flag is stored in the nc_vpid field which is
404 * otherwise unused.
405 */
406 pcp->pseminfo = psemp;
407 pcp->psem_nlen = pnp->psem_namelen;
408 bcopy(pnp->psem_nameptr, pcp->psem_name, pcp->psem_nlen);
409 pcp->psem_teamidlen = pnp->psem_teamidlen;
410 bcopy(pnp->psem_teamidptr, pcp->psem_teamid, pcp->psem_teamidlen);
411
412 /* Insert into the right table based on Team ID. */
413 if (pcp->psem_teamidlen > 0) {
414 pcpp = PSEMHASH(psem_local, pnp->psem_hash_local);
415 } else {
416 pcpp = PSEMHASH(psem_global, pnp->psem_hash_global);
417 }
418
419 #if DIAGNOSTIC
420 {
421 struct psemcache *p;
422
423 for (p = pcpp->lh_first; p != 0; p = p->psem_hash.le_next) {
424 if (p == pcp) {
425 panic("psem:cache_enter duplicate");
426 }
427 }
428 }
429 #endif
430 LIST_INSERT_HEAD(pcpp, pcp, psem_hash);
431 return 0;
432 }
433
434 /*
435 * Name cache initialization, from vfs_init() when we are booting
436 */
437 void
psem_cache_init(void)438 psem_cache_init(void)
439 {
440 /*
441 * The global table stores semaphores created by processes without a Team
442 * ID (such as platform binaries). The local table stores all other semaphores.
443 */
444 psem_global.psem_table = hashinit((int)(posix_sem_max / 2), M_SHM, &psem_global.psem_table_mask);
445 psem_local.psem_table = hashinit((int)(posix_sem_max / 2), M_SHM, &psem_local.psem_table_mask);
446
447 read_frandom(psem_global.psem_siphash_key, sizeof(psem_global.psem_siphash_key));
448 read_frandom(psem_local.psem_siphash_key, sizeof(psem_local.psem_siphash_key));
449 }
450
451 static void
psem_cache_delete(struct psemcache * pcp)452 psem_cache_delete(struct psemcache *pcp)
453 {
454 #if DIAGNOSTIC
455 if (pcp->psem_hash.le_prev == 0) {
456 panic("psem namecache purge le_prev");
457 }
458 if (pcp->psem_hash.le_next == pcp) {
459 panic("namecache purge le_next");
460 }
461 #endif /* DIAGNOSTIC */
462 LIST_REMOVE(pcp, psem_hash);
463 pcp->psem_hash.le_prev = NULL;
464 posix_sem_num--;
465 }
466
467 static int
psem_cache_purge_table(struct psemhashtable * table)468 psem_cache_purge_table(struct psemhashtable *table)
469 {
470 struct psemcache *pcp, *tmppcp;
471 struct psemhashhead *pcpp;
472
473 for (pcpp = &table->psem_table[table->psem_table_mask]; pcpp >= table->psem_table; pcpp--) {
474 LIST_FOREACH_SAFE(pcp, pcpp, psem_hash, tmppcp) {
475 assert(pcp->psem_nlen);
476 /*
477 * unconditionally unlink the cache entry
478 */
479 int error = psem_unlink_internal(pcp->pseminfo, pcp);
480 if (error) {
481 return error;
482 }
483 }
484 }
485
486 return 0;
487 }
488
489 /*
490 * Remove all cached psem entries. Open semaphores (with a positive refcount)
491 * will continue to exist, but their cache entries tying them to a particular
492 * name/path will be removed making all future lookups on the name fail.
493 */
494 int
psem_cache_purge_all(void)495 psem_cache_purge_all(void)
496 {
497 int error = 0;
498
499 if (kauth_cred_issuser(kauth_cred_get()) == 0) {
500 return EPERM;
501 }
502
503 PSEM_SUBSYS_LOCK();
504 error = psem_cache_purge_table(&psem_global);
505 if (error) {
506 goto out;
507 }
508 error = psem_cache_purge_table(&psem_local);
509 if (error) {
510 goto out;
511 }
512 assert(posix_sem_num == 0);
513
514 out:
515 PSEM_SUBSYS_UNLOCK();
516
517 if (error) {
518 printf("%s: Error %d removing all semaphores: %ld remain!\n",
519 __func__, error, posix_sem_num);
520 }
521 return error;
522 }
523
524 /*
525 * In order to support unnamed POSIX semaphores, the named
526 * POSIX semaphores will have to move out of the per-process
527 * open filetable, and into a global table that is shared with
528 * unnamed POSIX semaphores, since unnamed POSIX semaphores
529 * are typically used by declaring instances in shared memory,
530 * and there's no other way to do this without changing the
531 * underlying type, which would introduce binary compatibility
532 * issues.
533 */
534 int
sem_open(proc_t p,struct sem_open_args * uap,user_addr_t * retval)535 sem_open(proc_t p, struct sem_open_args *uap, user_addr_t *retval)
536 {
537 int indx, error;
538 struct psemname nd;
539 struct pseminfo *pinfo;
540 struct fileproc *fp = NULL;
541 char *pnbuf = NULL;
542 const char *teamid = NULL;
543 struct pseminfo *new_pinfo = PSEMINFO_NULL;
544 struct psemnode *new_pnode = PSEMNODE_NULL;
545 struct psemcache *pcache = PSEMCACHE_NULL;
546 char * nameptr;
547 size_t pathlen, plen, teamidlen;
548 mode_t fmode;
549 mode_t cmode = (mode_t)uap->mode;
550 int value = uap->value;
551 int incache = 0;
552 struct psemcache *pcp = PSEMCACHE_NULL;
553 kern_return_t kret = KERN_INVALID_ADDRESS; /* default fail */
554
555 AUDIT_ARG(fflags, uap->oflag);
556 AUDIT_ARG(mode, (mode_t)uap->mode);
557 AUDIT_ARG(value32, uap->value);
558
559 pinfo = PSEMINFO_NULL;
560
561 /*
562 * Preallocate everything we might need up front to avoid taking
563 * and dropping the lock, opening us up to race conditions.
564 */
565 pnbuf = zalloc_flags(ZV_NAMEI, Z_WAITOK | Z_ZERO);
566
567 pathlen = MAXPATHLEN;
568 error = copyinstr(uap->name, pnbuf, MAXPATHLEN, &pathlen);
569 if (error) {
570 goto bad;
571 }
572 AUDIT_ARG(text, pnbuf);
573 if ((pathlen > PSEMNAMLEN)) {
574 error = ENAMETOOLONG;
575 goto bad;
576 }
577
578 #ifdef PSXSEM_NAME_RESTRICT
579 nameptr = pnbuf;
580 if (*nameptr == '/') {
581 while (*(nameptr++) == '/') {
582 plen--;
583 error = EINVAL;
584 goto bad;
585 }
586 } else {
587 error = EINVAL;
588 goto bad;
589 }
590 #endif /* PSXSEM_NAME_RESTRICT */
591
592 plen = pathlen;
593 nameptr = pnbuf;
594 teamid = psem_get_teamid(p);
595 teamidlen = teamid ? strlen(teamid) : 0;
596 if (teamidlen > PSEMTEAMIDLEN) {
597 error = ENAMETOOLONG;
598 goto bad;
599 }
600 nd = psem_cache_hash(nameptr, plen, teamid, teamidlen);
601
602 /*
603 * attempt to allocate a new fp; if unsuccessful, the fp will be
604 * left unmodified (NULL).
605 */
606 error = falloc(p, &fp, &indx);
607 if (error) {
608 goto bad;
609 }
610
611 /*
612 * We allocate a new entry if we are less than the maximum
613 * allowed and the one at the front of the LRU list is in use.
614 * Otherwise we use the one at the front of the LRU list.
615 */
616 pcp = kalloc_type(struct psemcache, Z_WAITOK | Z_ZERO | Z_NOFAIL);
617 new_pinfo = kalloc_type(struct pseminfo, Z_WAITOK | Z_ZERO | Z_NOFAIL);
618 #if CONFIG_MACF
619 mac_posixsem_label_init(new_pinfo);
620 #endif
621
622 /*
623 * Provisionally create the semaphore in the new_pinfo; we have to do
624 * this here to prevent locking later. We use the value of kret to
625 * signal success or failure, which is why we set its default value
626 * to KERN_INVALID_ADDRESS, above.
627 */
628
629 fmode = (mode_t)FFLAGS(uap->oflag);
630
631 if ((fmode & O_CREAT)) {
632 if ((value < 0) || (value > SEM_VALUE_MAX)) {
633 error = EINVAL;
634 goto bad;
635 }
636
637 kret = semaphore_create(kernel_task, &new_pinfo->psem_semobject, SYNC_POLICY_FIFO, value);
638
639 if (kret != KERN_SUCCESS) {
640 switch (kret) {
641 case KERN_RESOURCE_SHORTAGE:
642 error = ENOMEM;
643 break;
644 case KERN_PROTECTION_FAILURE:
645 error = EACCES;
646 break;
647 default:
648 error = EINVAL;
649 }
650 goto bad;
651 }
652 }
653
654 new_pnode = kalloc_type(struct psemnode, Z_WAITOK | Z_ZERO | Z_NOFAIL);
655
656 PSEM_SUBSYS_LOCK();
657 error = psem_cache_search(&pinfo, &nd, &pcache);
658
659 if (error == PSEMCACHE_NEGATIVE) {
660 error = EINVAL;
661 goto bad_locked;
662 }
663
664 if (error == PSEMCACHE_FOUND) {
665 incache = 1;
666 } else {
667 incache = 0;
668 }
669
670 cmode &= ALLPERMS;
671
672 if (((fmode & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) && incache) {
673 /* sem exists and opened O_EXCL */
674 #if notyet
675 if (pinfo->psem_flags & PSEM_INDELETE) {
676 }
677 #endif
678 AUDIT_ARG(posix_ipc_perm, pinfo->psem_uid,
679 pinfo->psem_gid, pinfo->psem_mode);
680 error = EEXIST;
681 goto bad_locked;
682 }
683 if (((fmode & (O_CREAT | O_EXCL)) == O_CREAT) && incache) {
684 /* As per POSIX, O_CREAT has no effect */
685 fmode &= ~O_CREAT;
686 }
687
688 if ((fmode & O_CREAT)) {
689 /* create a new one (commit the allocation) */
690 pinfo = new_pinfo;
691 pinfo->psem_flags = PSEM_DEFINED | PSEM_INCREATE;
692 pinfo->psem_usecount = 1;
693 pinfo->psem_mode = cmode;
694 pinfo->psem_uid = kauth_getuid();
695 pinfo->psem_gid = kauth_getgid();
696 bcopy(pnbuf, &pinfo->psem_name[0], PSEMNAMLEN);
697 pinfo->psem_name[PSEMNAMLEN] = 0;
698 pinfo->psem_flags &= ~PSEM_DEFINED;
699 pinfo->psem_flags |= PSEM_ALLOCATED;
700 pinfo->psem_creator_pid = proc_getpid(p);
701 pinfo->psem_creator_uniqueid = proc_uniqueid(p);
702
703 #if CONFIG_MACF
704 error = mac_posixsem_check_create(kauth_cred_get(), nameptr);
705 if (error) {
706 goto bad_locked;
707 }
708 mac_posixsem_label_associate(kauth_cred_get(), pinfo, nameptr);
709 #endif
710 } else {
711 /* semaphore should exist as it is without O_CREAT */
712 if (!incache) {
713 error = ENOENT;
714 goto bad_locked;
715 }
716 if (pinfo->psem_flags & PSEM_INDELETE) {
717 error = ENOENT;
718 goto bad_locked;
719 }
720 AUDIT_ARG(posix_ipc_perm, pinfo->psem_uid,
721 pinfo->psem_gid, pinfo->psem_mode);
722 #if CONFIG_MACF
723 error = mac_posixsem_check_open(kauth_cred_get(), pinfo);
724 if (error) {
725 goto bad_locked;
726 }
727 #endif
728 if ((error = psem_access(pinfo, fmode, kauth_cred_get()))) {
729 goto bad_locked;
730 }
731 }
732
733 if (!incache) {
734 /* if successful, this will consume the pcp */
735 if ((error = psem_cache_add(pinfo, &nd, pcp))) {
736 goto bad_locked;
737 }
738 }
739 pinfo->psem_flags &= ~PSEM_INCREATE;
740 pinfo->psem_usecount++;
741 new_pnode->pinfo = pinfo;
742 PSEM_SUBSYS_UNLOCK();
743
744 /*
745 * if incache, we did not use the new pcp or the new pcp or the
746 * new . and we must free them.
747 */
748 if (incache) {
749 kfree_type(struct psemcache, pcp);
750 pcp = PSEMCACHE_NULL;
751 if (new_pinfo != PSEMINFO_NULL) {
752 /* return value ignored - we can't _not_ do this */
753 (void)semaphore_destroy(kernel_task, new_pinfo->psem_semobject);
754 #if CONFIG_MACF
755 mac_posixsem_label_destroy(new_pinfo);
756 #endif
757 kfree_type(struct pseminfo, new_pinfo);
758 new_pinfo = PSEMINFO_NULL;
759 }
760 }
761
762 proc_fdlock(p);
763 fp->f_flag = fmode & FMASK;
764 fp->f_ops = &psemops;
765 fp_set_data(fp, new_pnode);
766 procfdtbl_releasefd(p, indx, NULL);
767 fp_drop(p, indx, fp, 1);
768 proc_fdunlock(p);
769
770 *retval = CAST_USER_ADDR_T(indx);
771 zfree(ZV_NAMEI, pnbuf);
772 return 0;
773
774 bad_locked:
775 PSEM_SUBSYS_UNLOCK();
776 bad:
777 kfree_type(struct psemcache, pcp);
778
779 kfree_type(struct psemnode, new_pnode);
780
781 if (fp != NULL) {
782 fp_free(p, indx, fp);
783 }
784
785 if (new_pinfo != PSEMINFO_NULL) {
786 /*
787 * kret signals whether or not we successfully created a
788 * Mach semaphore for this semaphore; if so, we need to
789 * destroy it here.
790 */
791 if (kret == KERN_SUCCESS) {
792 /* return value ignored - we can't _not_ do this */
793 (void)semaphore_destroy(kernel_task, new_pinfo->psem_semobject);
794 }
795 #if CONFIG_MACF
796 mac_posixsem_label_destroy(new_pinfo);
797 #endif
798 kfree_type(struct pseminfo, new_pinfo);
799 }
800
801 if (pnbuf != NULL) {
802 zfree(ZV_NAMEI, pnbuf);
803 }
804 return error;
805 }
806
807 /*
808 * XXX This code is repeated in several places
809 */
810 static int
psem_access(struct pseminfo * pinfo,mode_t mode,kauth_cred_t cred)811 psem_access(struct pseminfo *pinfo, mode_t mode, kauth_cred_t cred)
812 {
813 mode_t mode_req = ((mode & FREAD) ? S_IRUSR : 0) |
814 ((mode & FWRITE) ? S_IWUSR : 0);
815
816 /* Otherwise, user id 0 always gets access. */
817 if (!suser(cred, NULL)) {
818 return 0;
819 }
820
821 return posix_cred_access(cred, pinfo->psem_uid, pinfo->psem_gid, pinfo->psem_mode, mode_req);
822 }
823
824 static int
psem_unlink_internal(struct pseminfo * pinfo,struct psemcache * pcache)825 psem_unlink_internal(struct pseminfo *pinfo, struct psemcache *pcache)
826 {
827 PSEM_SUBSYS_ASSERT_HELD();
828
829 if (!pinfo || !pcache) {
830 return EINVAL;
831 }
832
833 if ((pinfo->psem_flags & (PSEM_DEFINED | PSEM_ALLOCATED)) == 0) {
834 return EINVAL;
835 }
836
837 if (pinfo->psem_flags & PSEM_INDELETE) {
838 return 0;
839 }
840
841 AUDIT_ARG(posix_ipc_perm, pinfo->psem_uid, pinfo->psem_gid,
842 pinfo->psem_mode);
843
844 pinfo->psem_flags |= PSEM_INDELETE;
845 pinfo->psem_usecount--;
846
847 if (!pinfo->psem_usecount) {
848 psem_delete(pinfo);
849 kfree_type(struct pseminfo, pinfo);
850 } else {
851 pinfo->psem_flags |= PSEM_REMOVED;
852 }
853
854 psem_cache_delete(pcache);
855 kfree_type(struct psemcache, pcache);
856 return 0;
857 }
858
859 static const char *
psem_get_teamid(proc_t p)860 psem_get_teamid(proc_t p)
861 {
862 #if XNU_TARGET_OS_OSX
863 #pragma unused(p)
864 return NULL;
865 #else
866 return csproc_get_teamid(p);
867 #endif
868 }
869
870
871 int
sem_unlink(__unused proc_t p,struct sem_unlink_args * uap,__unused int32_t * retval)872 sem_unlink(__unused proc_t p, struct sem_unlink_args *uap, __unused int32_t *retval)
873 {
874 int error = 0;
875 struct psemname nd;
876 struct pseminfo *pinfo;
877 char * nameptr;
878 char * pnbuf;
879 const char *teamid;
880 size_t pathlen, teamidlen;
881 struct psemcache *pcache = PSEMCACHE_NULL;
882
883 pinfo = PSEMINFO_NULL;
884
885 pnbuf = zalloc(ZV_NAMEI);
886
887 pathlen = MAXPATHLEN;
888 error = copyinstr(uap->name, pnbuf, MAXPATHLEN, &pathlen);
889 if (error) {
890 goto bad;
891 }
892 AUDIT_ARG(text, pnbuf);
893 if (pathlen > PSEMNAMLEN) {
894 error = ENAMETOOLONG;
895 goto bad;
896 }
897
898 nameptr = pnbuf;
899
900 #ifdef PSXSEM_NAME_RESTRICT
901 if (*nameptr == '/') {
902 while (*(nameptr++) == '/') {
903 pathlen--;
904 error = EINVAL;
905 goto bad;
906 }
907 } else {
908 error = EINVAL;
909 goto bad;
910 }
911 #endif /* PSXSEM_NAME_RESTRICT */
912
913 teamid = psem_get_teamid(p);
914 teamidlen = teamid ? strlen(teamid) : 0;
915 if (teamidlen > PSEMTEAMIDLEN) {
916 error = ENAMETOOLONG;
917 goto bad;
918 }
919 nd = psem_cache_hash(nameptr, pathlen, teamid, teamidlen);
920
921 PSEM_SUBSYS_LOCK();
922 error = psem_cache_search(&pinfo, &nd, &pcache);
923
924 if (error != PSEMCACHE_FOUND) {
925 PSEM_SUBSYS_UNLOCK();
926 error = ENOENT;
927 goto bad;
928 }
929
930 #if CONFIG_MACF
931 error = mac_posixsem_check_unlink(kauth_cred_get(), pinfo, nameptr);
932 if (error) {
933 PSEM_SUBSYS_UNLOCK();
934 goto bad;
935 }
936 #endif
937 if ((error = psem_access(pinfo, pinfo->psem_mode, kauth_cred_get()))) {
938 PSEM_SUBSYS_UNLOCK();
939 goto bad;
940 }
941
942 error = psem_unlink_internal(pinfo, pcache);
943 PSEM_SUBSYS_UNLOCK();
944
945 bad:
946 zfree(ZV_NAMEI, pnbuf);
947 return error;
948 }
949
950 int
sem_close(proc_t p,struct sem_close_args * uap,__unused int32_t * retval)951 sem_close(proc_t p, struct sem_close_args *uap, __unused int32_t *retval)
952 {
953 int fd = CAST_DOWN_EXPLICIT(int, uap->sem);
954 kauth_cred_t p_cred;
955 struct fileproc *fp;
956
957 AUDIT_ARG(fd, fd); /* XXX This seems wrong; uap->sem is a pointer */
958
959 proc_fdlock(p);
960 if ((fp = fp_get_noref_locked(p, fd)) == NULL) {
961 proc_fdunlock(p);
962 return EBADF;
963 }
964 if (FILEGLOB_DTYPE(fp->fp_glob) != DTYPE_PSXSEM) {
965 proc_fdunlock(p);
966 return EBADF;
967 }
968
969 p_cred = current_cached_proc_cred(p);
970 return fp_close_and_unlock(p, p_cred, fd, fp, 0);
971 }
972
973 int
sem_wait(proc_t p,struct sem_wait_args * uap,int32_t * retval)974 sem_wait(proc_t p, struct sem_wait_args *uap, int32_t *retval)
975 {
976 __pthread_testcancel(1);
977 return sem_wait_nocancel(p, (struct sem_wait_nocancel_args *)uap, retval);
978 }
979
980 int
sem_wait_nocancel(proc_t p,struct sem_wait_nocancel_args * uap,__unused int32_t * retval)981 sem_wait_nocancel(proc_t p, struct sem_wait_nocancel_args *uap, __unused int32_t *retval)
982 {
983 int fd = CAST_DOWN_EXPLICIT(int, uap->sem);
984 struct fileproc *fp;
985 struct pseminfo * pinfo;
986 struct psemnode * pnode;
987 kern_return_t kret;
988 int error;
989
990 error = fp_get_ftype(p, fd, DTYPE_PSXSEM, EBADF, &fp);
991 if (error) {
992 return error;
993 }
994 pnode = (struct psemnode *)fp_get_data(fp);
995
996 PSEM_SUBSYS_LOCK();
997 if ((pinfo = pnode->pinfo) == PSEMINFO_NULL) {
998 PSEM_SUBSYS_UNLOCK();
999 error = EINVAL;
1000 goto out;
1001 }
1002 if ((pinfo->psem_flags & (PSEM_DEFINED | PSEM_ALLOCATED))
1003 != PSEM_ALLOCATED) {
1004 PSEM_SUBSYS_UNLOCK();
1005 error = EINVAL;
1006 goto out;
1007 }
1008 #if CONFIG_MACF
1009 error = mac_posixsem_check_wait(kauth_cred_get(), pinfo);
1010 if (error) {
1011 PSEM_SUBSYS_UNLOCK();
1012 goto out;
1013 }
1014 #endif
1015 PSEM_SUBSYS_UNLOCK();
1016 kret = semaphore_wait(pinfo->psem_semobject);
1017 switch (kret) {
1018 case KERN_INVALID_ADDRESS:
1019 case KERN_PROTECTION_FAILURE:
1020 error = EACCES;
1021 break;
1022 case KERN_ABORTED:
1023 case KERN_OPERATION_TIMED_OUT:
1024 error = EINTR;
1025 break;
1026 case KERN_SUCCESS:
1027 error = 0;
1028 break;
1029 default:
1030 error = EINVAL;
1031 break;
1032 }
1033 out:
1034 fp_drop(p, fd, fp, 0);
1035 return error;
1036 }
1037
1038 int
sem_trywait(proc_t p,struct sem_trywait_args * uap,__unused int32_t * retval)1039 sem_trywait(proc_t p, struct sem_trywait_args *uap, __unused int32_t *retval)
1040 {
1041 int fd = CAST_DOWN_EXPLICIT(int, uap->sem);
1042 struct fileproc *fp;
1043 struct pseminfo * pinfo;
1044 struct psemnode * pnode;
1045 kern_return_t kret;
1046 mach_timespec_t wait_time;
1047 int error;
1048
1049 error = fp_get_ftype(p, fd, DTYPE_PSXSEM, EBADF, &fp);
1050 if (error) {
1051 return error;
1052 }
1053 pnode = (struct psemnode *)fp_get_data(fp);
1054
1055 PSEM_SUBSYS_LOCK();
1056 if ((pinfo = pnode->pinfo) == PSEMINFO_NULL) {
1057 PSEM_SUBSYS_UNLOCK();
1058 error = EINVAL;
1059 goto out;
1060 }
1061 if ((pinfo->psem_flags & (PSEM_DEFINED | PSEM_ALLOCATED))
1062 != PSEM_ALLOCATED) {
1063 PSEM_SUBSYS_UNLOCK();
1064 error = EINVAL;
1065 goto out;
1066 }
1067 #if CONFIG_MACF
1068 error = mac_posixsem_check_wait(kauth_cred_get(), pinfo);
1069 if (error) {
1070 PSEM_SUBSYS_UNLOCK();
1071 goto out;
1072 }
1073 #endif
1074 PSEM_SUBSYS_UNLOCK();
1075 wait_time.tv_sec = 0;
1076 wait_time.tv_nsec = 0;
1077
1078 kret = semaphore_timedwait(pinfo->psem_semobject, MACH_TIMESPEC_ZERO);
1079 switch (kret) {
1080 case KERN_INVALID_ADDRESS:
1081 case KERN_PROTECTION_FAILURE:
1082 error = EINVAL;
1083 break;
1084 case KERN_ABORTED:
1085 error = EINTR;
1086 break;
1087 case KERN_OPERATION_TIMED_OUT:
1088 error = EAGAIN;
1089 break;
1090 case KERN_SUCCESS:
1091 error = 0;
1092 break;
1093 default:
1094 error = EINVAL;
1095 break;
1096 }
1097 out:
1098 fp_drop(p, fd, fp, 0);
1099 return error;
1100 }
1101
1102 int
sem_post(proc_t p,struct sem_post_args * uap,__unused int32_t * retval)1103 sem_post(proc_t p, struct sem_post_args *uap, __unused int32_t *retval)
1104 {
1105 int fd = CAST_DOWN_EXPLICIT(int, uap->sem);
1106 struct fileproc *fp;
1107 struct pseminfo * pinfo;
1108 struct psemnode * pnode;
1109 kern_return_t kret;
1110 int error;
1111
1112 error = fp_get_ftype(p, fd, DTYPE_PSXSEM, EBADF, &fp);
1113 if (error) {
1114 return error;
1115 }
1116 pnode = (struct psemnode *)fp_get_data(fp);
1117
1118 PSEM_SUBSYS_LOCK();
1119 if ((pinfo = pnode->pinfo) == PSEMINFO_NULL) {
1120 PSEM_SUBSYS_UNLOCK();
1121 error = EINVAL;
1122 goto out;
1123 }
1124 if ((pinfo->psem_flags & (PSEM_DEFINED | PSEM_ALLOCATED))
1125 != PSEM_ALLOCATED) {
1126 PSEM_SUBSYS_UNLOCK();
1127 error = EINVAL;
1128 goto out;
1129 }
1130 #if CONFIG_MACF
1131 error = mac_posixsem_check_post(kauth_cred_get(), pinfo);
1132 if (error) {
1133 PSEM_SUBSYS_UNLOCK();
1134 goto out;
1135 }
1136 #endif
1137 PSEM_SUBSYS_UNLOCK();
1138 kret = semaphore_signal(pinfo->psem_semobject);
1139 switch (kret) {
1140 case KERN_INVALID_ADDRESS:
1141 case KERN_PROTECTION_FAILURE:
1142 error = EINVAL;
1143 break;
1144 case KERN_ABORTED:
1145 case KERN_OPERATION_TIMED_OUT:
1146 error = EINTR;
1147 break;
1148 case KERN_SUCCESS:
1149 error = 0;
1150 break;
1151 default:
1152 error = EINVAL;
1153 break;
1154 }
1155 out:
1156 fp_drop(p, fd, fp, 0);
1157 return error;
1158 }
1159
1160 static int
psem_close(struct psemnode * pnode)1161 psem_close(struct psemnode *pnode)
1162 {
1163 int error = 0;
1164 struct pseminfo *pinfo;
1165
1166 PSEM_SUBSYS_LOCK();
1167 if ((pinfo = pnode->pinfo) == PSEMINFO_NULL) {
1168 PSEM_SUBSYS_UNLOCK();
1169 return EINVAL;
1170 }
1171
1172 if ((pinfo->psem_flags & PSEM_ALLOCATED) != PSEM_ALLOCATED) {
1173 PSEM_SUBSYS_UNLOCK();
1174 return EINVAL;
1175 }
1176 #if DIAGNOSTIC
1177 if (!pinfo->psem_usecount) {
1178 kprintf("negative usecount in psem_close\n");
1179 }
1180 #endif /* DIAGNOSTIC */
1181 pinfo->psem_usecount--;
1182
1183 if ((pinfo->psem_flags & PSEM_REMOVED) && !pinfo->psem_usecount) {
1184 PSEM_SUBSYS_UNLOCK();
1185 /* lock dropped as only semaphore is destroyed here */
1186 error = psem_delete(pinfo);
1187 kfree_type(struct pseminfo, pinfo);
1188 } else {
1189 PSEM_SUBSYS_UNLOCK();
1190 }
1191 /* subsystem lock is dropped when we get here */
1192 kfree_type(struct psemnode, pnode);
1193 return error;
1194 }
1195
1196 static int
psem_closefile(struct fileglob * fg,__unused vfs_context_t ctx)1197 psem_closefile(struct fileglob *fg, __unused vfs_context_t ctx)
1198 {
1199 /*
1200 * Not locked as psem_close is called only from here and is locked
1201 * properly
1202 */
1203 return psem_close((struct psemnode *)fg_get_data(fg));
1204 }
1205
1206 static int
psem_delete(struct pseminfo * pinfo)1207 psem_delete(struct pseminfo * pinfo)
1208 {
1209 kern_return_t kret;
1210
1211 kret = semaphore_destroy(kernel_task, pinfo->psem_semobject);
1212 #if CONFIG_MACF
1213 mac_posixsem_label_destroy(pinfo);
1214 #endif
1215
1216 switch (kret) {
1217 case KERN_INVALID_ADDRESS:
1218 case KERN_PROTECTION_FAILURE:
1219 return EINVAL;
1220 case KERN_ABORTED:
1221 case KERN_OPERATION_TIMED_OUT:
1222 return EINTR;
1223 case KERN_SUCCESS:
1224 return 0;
1225 default:
1226 return EINVAL;
1227 }
1228 }
1229
1230 int
fill_pseminfo(struct psemnode * pnode,struct psem_info * info)1231 fill_pseminfo(struct psemnode *pnode, struct psem_info * info)
1232 {
1233 struct pseminfo *pinfo;
1234 struct vinfo_stat *sb;
1235
1236 PSEM_SUBSYS_LOCK();
1237 if ((pinfo = pnode->pinfo) == PSEMINFO_NULL) {
1238 PSEM_SUBSYS_UNLOCK();
1239 return EINVAL;
1240 }
1241
1242 #if 0
1243 if ((pinfo->psem_flags & PSEM_ALLOCATED) != PSEM_ALLOCATED) {
1244 PSEM_SUBSYS_UNLOCK();
1245 return EINVAL;
1246 }
1247 #endif
1248
1249 sb = &info->psem_stat;
1250 bzero(sb, sizeof(struct vinfo_stat));
1251
1252 sb->vst_mode = pinfo->psem_mode;
1253 sb->vst_uid = pinfo->psem_uid;
1254 sb->vst_gid = pinfo->psem_gid;
1255 sb->vst_size = pinfo->psem_usecount;
1256 bcopy(&pinfo->psem_name[0], &info->psem_name[0], PSEMNAMLEN + 1);
1257
1258 PSEM_SUBSYS_UNLOCK();
1259 return 0;
1260 }
1261
1262 #if CONFIG_MACF
1263 void
psem_label_associate(struct fileproc * fp,struct vnode * vp,vfs_context_t ctx)1264 psem_label_associate(struct fileproc *fp, struct vnode *vp, vfs_context_t ctx)
1265 {
1266 struct psemnode *pnode;
1267 struct pseminfo *psem;
1268
1269 PSEM_SUBSYS_LOCK();
1270 pnode = (struct psemnode *)fp_get_data(fp);
1271 if (pnode != NULL) {
1272 psem = pnode->pinfo;
1273 if (psem != NULL) {
1274 mac_posixsem_vnode_label_associate(
1275 vfs_context_ucred(ctx), psem,
1276 mac_posixsem_label(psem),
1277 vp, mac_vnode_label(vp));
1278 }
1279 }
1280 PSEM_SUBSYS_UNLOCK();
1281 }
1282 #endif
1283