1 /*-
2 * Implementation of SVID semaphores
3 *
4 * Author: Daniel Boulet
5 *
6 * This software is provided ``AS IS'' without any warranties of any kind.
7 */
8 /*-
9 * SPDX-License-Identifier: BSD-2-Clause
10 *
11 * Copyright (c) 2003-2005 McAfee, Inc.
12 * Copyright (c) 2016-2017 Robert N. M. Watson
13 * All rights reserved.
14 *
15 * This software was developed for the FreeBSD Project in part by McAfee
16 * Research, the Security Research Division of McAfee, Inc under DARPA/SPAWAR
17 * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS research
18 * program.
19 *
20 * Portions of this software were developed by BAE Systems, the University of
21 * Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL
22 * contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent
23 * Computing (TC) research program.
24 *
25 * Redistribution and use in source and binary forms, with or without
26 * modification, are permitted provided that the following conditions
27 * are met:
28 * 1. Redistributions of source code must retain the above copyright
29 * notice, this list of conditions and the following disclaimer.
30 * 2. Redistributions in binary form must reproduce the above copyright
31 * notice, this list of conditions and the following disclaimer in the
32 * documentation and/or other materials provided with the distribution.
33 *
34 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
35 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
36 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
37 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
38 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
39 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
40 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
41 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
42 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
43 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
44 * SUCH DAMAGE.
45 */
46
47 #include "opt_sysvipc.h"
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/sysproto.h>
52 #include <sys/abi_compat.h>
53 #include <sys/eventhandler.h>
54 #include <sys/kernel.h>
55 #include <sys/proc.h>
56 #include <sys/lock.h>
57 #include <sys/module.h>
58 #include <sys/mutex.h>
59 #include <sys/racct.h>
60 #include <sys/sem.h>
61 #include <sys/sx.h>
62 #include <sys/syscall.h>
63 #include <sys/syscallsubr.h>
64 #include <sys/sysent.h>
65 #include <sys/sysctl.h>
66 #include <sys/uio.h>
67 #include <sys/malloc.h>
68 #include <sys/jail.h>
69
70 #include <security/audit/audit.h>
71 #include <security/mac/mac_framework.h>
72
73 FEATURE(sysv_sem, "System V semaphores support");
74
75 static MALLOC_DEFINE(M_SEM, "sem", "SVID compatible semaphores");
76
77 #ifdef SEM_DEBUG
78 #define DPRINTF(a) printf a
79 #else
80 #define DPRINTF(a)
81 #endif
82
83 static int seminit(void);
84 static int sysvsem_modload(struct module *, int, void *);
85 static int semunload(void);
86 static void semexit_myhook(void *arg, struct proc *p);
87 static int sysctl_sema(SYSCTL_HANDLER_ARGS);
88 static int semvalid(int semid, struct prison *rpr,
89 struct semid_kernel *semakptr);
90 static void sem_remove(int semidx, struct ucred *cred);
91 static struct prison *sem_find_prison(struct ucred *);
92 static int sem_prison_cansee(struct prison *, struct semid_kernel *);
93 static int sem_prison_check(void *, void *);
94 static int sem_prison_set(void *, void *);
95 static int sem_prison_get(void *, void *);
96 static int sem_prison_remove(void *, void *);
97 static void sem_prison_cleanup(struct prison *);
98
99 #ifndef _SYS_SYSPROTO_H_
100 struct __semctl_args;
101 int __semctl(struct thread *td, struct __semctl_args *uap);
102 struct semget_args;
103 int semget(struct thread *td, struct semget_args *uap);
104 struct semop_args;
105 int semop(struct thread *td, struct semop_args *uap);
106 #endif
107
108 static struct sem_undo *semu_alloc(struct thread *td);
109 static int semundo_adjust(struct thread *td, struct sem_undo **supptr,
110 int semid, int semseq, int semnum, int adjval);
111 static void semundo_clear(int semid, int semnum);
112
113 static struct mtx sem_mtx; /* semaphore global lock */
114 static struct mtx sem_undo_mtx;
115 static int semtot = 0;
116 static struct semid_kernel *sema; /* semaphore id pool */
117 static struct mtx *sema_mtx; /* semaphore id pool mutexes*/
118 static struct sem *sem; /* semaphore pool */
119 LIST_HEAD(, sem_undo) semu_list; /* list of active undo structures */
120 LIST_HEAD(, sem_undo) semu_free_list; /* list of free undo structures */
121 static int *semu; /* undo structure pool */
122 static eventhandler_tag semexit_tag;
123 static unsigned sem_prison_slot; /* prison OSD slot */
124
125 #define SEMUNDO_MTX sem_undo_mtx
126 #define SEMUNDO_LOCK() mtx_lock(&SEMUNDO_MTX);
127 #define SEMUNDO_UNLOCK() mtx_unlock(&SEMUNDO_MTX);
128 #define SEMUNDO_LOCKASSERT(how) mtx_assert(&SEMUNDO_MTX, (how));
129
130 struct sem {
131 u_short semval; /* semaphore value */
132 pid_t sempid; /* pid of last operation */
133 u_short semncnt; /* # awaiting semval > cval */
134 u_short semzcnt; /* # awaiting semval = 0 */
135 };
136
137 /*
138 * Undo structure (one per process)
139 */
140 struct sem_undo {
141 LIST_ENTRY(sem_undo) un_next; /* ptr to next active undo structure */
142 struct proc *un_proc; /* owner of this structure */
143 short un_cnt; /* # of active entries */
144 struct undo {
145 short un_adjval; /* adjust on exit values */
146 short un_num; /* semaphore # */
147 int un_id; /* semid */
148 unsigned short un_seq;
149 } un_ent[1]; /* undo entries */
150 };
151
152 /*
153 * Configuration parameters
154 */
155 #ifndef SEMMNI
156 #define SEMMNI 50 /* # of semaphore identifiers */
157 #endif
158 #ifndef SEMMNS
159 #define SEMMNS 340 /* # of semaphores in system */
160 #endif
161 #ifndef SEMUME
162 #define SEMUME 50 /* max # of undo entries per process */
163 #endif
164 #ifndef SEMMNU
165 #define SEMMNU 150 /* # of undo structures in system */
166 #endif
167
168 /* shouldn't need tuning */
169 #ifndef SEMMSL
170 #define SEMMSL SEMMNS /* max # of semaphores per id */
171 #endif
172 #ifndef SEMOPM
173 #define SEMOPM 100 /* max # of operations per semop call */
174 #endif
175
176 #define SEMVMX 32767 /* semaphore maximum value */
177 #define SEMAEM 16384 /* adjust on exit max value */
178
179 /*
180 * Due to the way semaphore memory is allocated, we have to ensure that
181 * SEMUSZ is properly aligned.
182 */
183
184 #define SEM_ALIGN(bytes) roundup2(bytes, sizeof(long))
185
186 /* actual size of an undo structure */
187 #define SEMUSZ(x) SEM_ALIGN(offsetof(struct sem_undo, un_ent[(x)]))
188
189 /*
190 * Macro to find a particular sem_undo vector
191 */
192 #define SEMU(ix) \
193 ((struct sem_undo *)(((intptr_t)semu) + (ix) * seminfo.semusz))
194
195 /*
196 * semaphore info struct
197 */
198 struct seminfo seminfo = {
199 .semmni = SEMMNI, /* # of semaphore identifiers */
200 .semmns = SEMMNS, /* # of semaphores in system */
201 .semmnu = SEMMNU, /* # of undo structures in system */
202 .semmsl = SEMMSL, /* max # of semaphores per id */
203 .semopm = SEMOPM, /* max # of operations per semop call */
204 .semume = SEMUME, /* max # of undo entries per process */
205 .semusz = SEMUSZ(SEMUME), /* size in bytes of undo structure */
206 .semvmx = SEMVMX, /* semaphore maximum value */
207 .semaem = SEMAEM, /* adjust on exit max value */
208 };
209
210 SYSCTL_INT(_kern_ipc, OID_AUTO, semmni, CTLFLAG_RDTUN, &seminfo.semmni, 0,
211 "Number of semaphore identifiers");
212 SYSCTL_INT(_kern_ipc, OID_AUTO, semmns, CTLFLAG_RDTUN, &seminfo.semmns, 0,
213 "Maximum number of semaphores in the system");
214 SYSCTL_INT(_kern_ipc, OID_AUTO, semmnu, CTLFLAG_RDTUN, &seminfo.semmnu, 0,
215 "Maximum number of undo structures in the system");
216 SYSCTL_INT(_kern_ipc, OID_AUTO, semmsl, CTLFLAG_RWTUN, &seminfo.semmsl, 0,
217 "Max semaphores per id");
218 SYSCTL_INT(_kern_ipc, OID_AUTO, semopm, CTLFLAG_RDTUN, &seminfo.semopm, 0,
219 "Max operations per semop call");
220 SYSCTL_INT(_kern_ipc, OID_AUTO, semume, CTLFLAG_RDTUN, &seminfo.semume, 0,
221 "Max undo entries per process");
222 SYSCTL_INT(_kern_ipc, OID_AUTO, semusz, CTLFLAG_RD, &seminfo.semusz, 0,
223 "Size in bytes of undo structure");
224 SYSCTL_INT(_kern_ipc, OID_AUTO, semvmx, CTLFLAG_RWTUN, &seminfo.semvmx, 0,
225 "Semaphore maximum value");
226 SYSCTL_INT(_kern_ipc, OID_AUTO, semaem, CTLFLAG_RWTUN, &seminfo.semaem, 0,
227 "Adjust on exit max value");
228 SYSCTL_PROC(_kern_ipc, OID_AUTO, sema,
229 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE,
230 NULL, 0, sysctl_sema, "",
231 "Array of struct semid_kernel for each potential semaphore");
232
233 static struct syscall_helper_data sem_syscalls[] = {
234 SYSCALL_INIT_HELPER(__semctl),
235 SYSCALL_INIT_HELPER(semget),
236 SYSCALL_INIT_HELPER(semop),
237 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
238 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
239 SYSCALL_INIT_HELPER(semsys),
240 SYSCALL_INIT_HELPER_COMPAT(freebsd7___semctl),
241 #endif
242 SYSCALL_INIT_LAST
243 };
244
245 #ifdef COMPAT_FREEBSD32
246 #include <compat/freebsd32/freebsd32.h>
247 #include <compat/freebsd32/freebsd32_ipc.h>
248 #include <compat/freebsd32/freebsd32_proto.h>
249 #include <compat/freebsd32/freebsd32_signal.h>
250 #include <compat/freebsd32/freebsd32_syscall.h>
251 #include <compat/freebsd32/freebsd32_util.h>
252
253 static struct syscall_helper_data sem32_syscalls[] = {
254 SYSCALL32_INIT_HELPER(freebsd32___semctl),
255 SYSCALL32_INIT_HELPER_COMPAT(semget),
256 SYSCALL32_INIT_HELPER_COMPAT(semop),
257 SYSCALL32_INIT_HELPER(freebsd32_semsys),
258 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
259 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
260 SYSCALL32_INIT_HELPER(freebsd7_freebsd32___semctl),
261 #endif
262 SYSCALL_INIT_LAST
263 };
264 #endif
265
266 static int
seminit(void)267 seminit(void)
268 {
269 struct prison *pr;
270 void **rsv;
271 int i, error;
272 osd_method_t methods[PR_MAXMETHOD] = {
273 [PR_METHOD_CHECK] = sem_prison_check,
274 [PR_METHOD_SET] = sem_prison_set,
275 [PR_METHOD_GET] = sem_prison_get,
276 [PR_METHOD_REMOVE] = sem_prison_remove,
277 };
278
279 sem = malloc(sizeof(struct sem) * seminfo.semmns, M_SEM, M_WAITOK);
280 sema = malloc(sizeof(struct semid_kernel) * seminfo.semmni, M_SEM,
281 M_WAITOK | M_ZERO);
282 sema_mtx = malloc(sizeof(struct mtx) * seminfo.semmni, M_SEM,
283 M_WAITOK | M_ZERO);
284 seminfo.semusz = SEMUSZ(seminfo.semume);
285 semu = malloc(seminfo.semmnu * seminfo.semusz, M_SEM, M_WAITOK);
286
287 for (i = 0; i < seminfo.semmni; i++) {
288 sema[i].u.__sem_base = 0;
289 sema[i].u.sem_perm.mode = 0;
290 sema[i].u.sem_perm.seq = 0;
291 #ifdef MAC
292 mac_sysvsem_init(&sema[i]);
293 #endif
294 }
295 for (i = 0; i < seminfo.semmni; i++)
296 mtx_init(&sema_mtx[i], "semid", NULL, MTX_DEF);
297 LIST_INIT(&semu_free_list);
298 for (i = 0; i < seminfo.semmnu; i++) {
299 struct sem_undo *suptr = SEMU(i);
300 suptr->un_proc = NULL;
301 LIST_INSERT_HEAD(&semu_free_list, suptr, un_next);
302 }
303 LIST_INIT(&semu_list);
304 mtx_init(&sem_mtx, "sem", NULL, MTX_DEF);
305 mtx_init(&sem_undo_mtx, "semu", NULL, MTX_DEF);
306 semexit_tag = EVENTHANDLER_REGISTER(process_exit, semexit_myhook, NULL,
307 EVENTHANDLER_PRI_ANY);
308
309 /* Set current prisons according to their allow.sysvipc. */
310 sem_prison_slot = osd_jail_register(NULL, methods);
311 rsv = osd_reserve(sem_prison_slot);
312 prison_lock(&prison0);
313 (void)osd_jail_set_reserved(&prison0, sem_prison_slot, rsv, &prison0);
314 prison_unlock(&prison0);
315 rsv = NULL;
316 sx_slock(&allprison_lock);
317 TAILQ_FOREACH(pr, &allprison, pr_list) {
318 if (rsv == NULL)
319 rsv = osd_reserve(sem_prison_slot);
320 prison_lock(pr);
321 if (pr->pr_allow & PR_ALLOW_SYSVIPC) {
322 (void)osd_jail_set_reserved(pr, sem_prison_slot, rsv,
323 &prison0);
324 rsv = NULL;
325 }
326 prison_unlock(pr);
327 }
328 if (rsv != NULL)
329 osd_free_reserved(rsv);
330 sx_sunlock(&allprison_lock);
331
332 error = syscall_helper_register(sem_syscalls, SY_THR_STATIC_KLD);
333 if (error != 0)
334 return (error);
335 #ifdef COMPAT_FREEBSD32
336 error = syscall32_helper_register(sem32_syscalls, SY_THR_STATIC_KLD);
337 if (error != 0)
338 return (error);
339 #endif
340 return (0);
341 }
342
343 static int
semunload(void)344 semunload(void)
345 {
346 int i;
347
348 /* XXXKIB */
349 if (semtot != 0)
350 return (EBUSY);
351
352 #ifdef COMPAT_FREEBSD32
353 syscall32_helper_unregister(sem32_syscalls);
354 #endif
355 syscall_helper_unregister(sem_syscalls);
356 EVENTHANDLER_DEREGISTER(process_exit, semexit_tag);
357 if (sem_prison_slot != 0)
358 osd_jail_deregister(sem_prison_slot);
359 #ifdef MAC
360 for (i = 0; i < seminfo.semmni; i++)
361 mac_sysvsem_destroy(&sema[i]);
362 #endif
363 free(sem, M_SEM);
364 free(sema, M_SEM);
365 free(semu, M_SEM);
366 for (i = 0; i < seminfo.semmni; i++)
367 mtx_destroy(&sema_mtx[i]);
368 free(sema_mtx, M_SEM);
369 mtx_destroy(&sem_mtx);
370 mtx_destroy(&sem_undo_mtx);
371 return (0);
372 }
373
374 static int
sysvsem_modload(struct module * module,int cmd,void * arg)375 sysvsem_modload(struct module *module, int cmd, void *arg)
376 {
377 int error = 0;
378
379 switch (cmd) {
380 case MOD_LOAD:
381 error = seminit();
382 break;
383 case MOD_UNLOAD:
384 error = semunload();
385 break;
386 case MOD_SHUTDOWN:
387 break;
388 default:
389 error = EINVAL;
390 break;
391 }
392 return (error);
393 }
394
395 static moduledata_t sysvsem_mod = {
396 "sysvsem",
397 &sysvsem_modload,
398 NULL
399 };
400
401 DECLARE_MODULE(sysvsem, sysvsem_mod, SI_SUB_SYSV_SEM, SI_ORDER_FIRST);
402 MODULE_VERSION(sysvsem, 1);
403
404 /*
405 * Allocate a new sem_undo structure for a process
406 * (returns ptr to structure or NULL if no more room)
407 */
408
409 static struct sem_undo *
semu_alloc(struct thread * td)410 semu_alloc(struct thread *td)
411 {
412 struct sem_undo *suptr;
413
414 SEMUNDO_LOCKASSERT(MA_OWNED);
415 if ((suptr = LIST_FIRST(&semu_free_list)) == NULL)
416 return (NULL);
417 LIST_REMOVE(suptr, un_next);
418 LIST_INSERT_HEAD(&semu_list, suptr, un_next);
419 suptr->un_cnt = 0;
420 suptr->un_proc = td->td_proc;
421 return (suptr);
422 }
423
424 static int
semu_try_free(struct sem_undo * suptr)425 semu_try_free(struct sem_undo *suptr)
426 {
427
428 SEMUNDO_LOCKASSERT(MA_OWNED);
429
430 if (suptr->un_cnt != 0)
431 return (0);
432 LIST_REMOVE(suptr, un_next);
433 LIST_INSERT_HEAD(&semu_free_list, suptr, un_next);
434 return (1);
435 }
436
437 /*
438 * Adjust a particular entry for a particular proc
439 */
440
441 static int
semundo_adjust(struct thread * td,struct sem_undo ** supptr,int semid,int semseq,int semnum,int adjval)442 semundo_adjust(struct thread *td, struct sem_undo **supptr, int semid,
443 int semseq, int semnum, int adjval)
444 {
445 struct proc *p = td->td_proc;
446 struct sem_undo *suptr;
447 struct undo *sunptr;
448 int i;
449
450 SEMUNDO_LOCKASSERT(MA_OWNED);
451 /* Look for and remember the sem_undo if the caller doesn't provide
452 it */
453
454 suptr = *supptr;
455 if (suptr == NULL) {
456 LIST_FOREACH(suptr, &semu_list, un_next) {
457 if (suptr->un_proc == p) {
458 *supptr = suptr;
459 break;
460 }
461 }
462 if (suptr == NULL) {
463 if (adjval == 0)
464 return(0);
465 suptr = semu_alloc(td);
466 if (suptr == NULL)
467 return (ENOSPC);
468 *supptr = suptr;
469 }
470 }
471
472 /*
473 * Look for the requested entry and adjust it (delete if adjval becomes
474 * 0).
475 */
476 sunptr = &suptr->un_ent[0];
477 for (i = 0; i < suptr->un_cnt; i++, sunptr++) {
478 if (sunptr->un_id != semid || sunptr->un_num != semnum)
479 continue;
480 if (adjval != 0) {
481 adjval += sunptr->un_adjval;
482 if (adjval > seminfo.semaem || adjval < -seminfo.semaem)
483 return (ERANGE);
484 }
485 sunptr->un_adjval = adjval;
486 if (sunptr->un_adjval == 0) {
487 suptr->un_cnt--;
488 if (i < suptr->un_cnt)
489 suptr->un_ent[i] =
490 suptr->un_ent[suptr->un_cnt];
491 if (suptr->un_cnt == 0)
492 semu_try_free(suptr);
493 }
494 return (0);
495 }
496
497 /* Didn't find the right entry - create it */
498 if (adjval == 0)
499 return (0);
500 if (adjval > seminfo.semaem || adjval < -seminfo.semaem)
501 return (ERANGE);
502 if (suptr->un_cnt != seminfo.semume) {
503 sunptr = &suptr->un_ent[suptr->un_cnt];
504 suptr->un_cnt++;
505 sunptr->un_adjval = adjval;
506 sunptr->un_id = semid;
507 sunptr->un_num = semnum;
508 sunptr->un_seq = semseq;
509 } else
510 return (EINVAL);
511 return (0);
512 }
513
514 static void
semundo_clear(int semid,int semnum)515 semundo_clear(int semid, int semnum)
516 {
517 struct sem_undo *suptr, *suptr1;
518 struct undo *sunptr;
519 int i;
520
521 SEMUNDO_LOCKASSERT(MA_OWNED);
522 LIST_FOREACH_SAFE(suptr, &semu_list, un_next, suptr1) {
523 sunptr = &suptr->un_ent[0];
524 for (i = 0; i < suptr->un_cnt; i++, sunptr++) {
525 if (sunptr->un_id != semid)
526 continue;
527 if (semnum == -1 || sunptr->un_num == semnum) {
528 suptr->un_cnt--;
529 if (i < suptr->un_cnt) {
530 suptr->un_ent[i] =
531 suptr->un_ent[suptr->un_cnt];
532 continue;
533 }
534 semu_try_free(suptr);
535 }
536 if (semnum != -1)
537 break;
538 }
539 }
540 }
541
542 static int
semvalid(int semid,struct prison * rpr,struct semid_kernel * semakptr)543 semvalid(int semid, struct prison *rpr, struct semid_kernel *semakptr)
544 {
545
546 return ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 ||
547 semakptr->u.sem_perm.seq != IPCID_TO_SEQ(semid) ||
548 sem_prison_cansee(rpr, semakptr) ? EINVAL : 0);
549 }
550
551 static void
sem_remove(int semidx,struct ucred * cred)552 sem_remove(int semidx, struct ucred *cred)
553 {
554 struct semid_kernel *semakptr;
555 int i;
556
557 KASSERT(semidx >= 0 && semidx < seminfo.semmni,
558 ("semidx out of bounds"));
559 mtx_assert(&sem_mtx, MA_OWNED);
560 semakptr = &sema[semidx];
561 KASSERT(semakptr->u.__sem_base - sem + semakptr->u.sem_nsems <= semtot,
562 ("sem_remove: sema %d corrupted sem pointer %p %p %d %d",
563 semidx, semakptr->u.__sem_base, sem, semakptr->u.sem_nsems,
564 semtot));
565
566 semakptr->u.sem_perm.cuid = cred ? cred->cr_uid : 0;
567 semakptr->u.sem_perm.uid = cred ? cred->cr_uid : 0;
568 semakptr->u.sem_perm.mode = 0;
569 racct_sub_cred(semakptr->cred, RACCT_NSEM, semakptr->u.sem_nsems);
570 crfree(semakptr->cred);
571 semakptr->cred = NULL;
572 SEMUNDO_LOCK();
573 semundo_clear(semidx, -1);
574 SEMUNDO_UNLOCK();
575 #ifdef MAC
576 mac_sysvsem_cleanup(semakptr);
577 #endif
578 wakeup(semakptr);
579 for (i = 0; i < seminfo.semmni; i++) {
580 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) &&
581 sema[i].u.__sem_base > semakptr->u.__sem_base)
582 mtx_lock_flags(&sema_mtx[i], LOP_DUPOK);
583 }
584 for (i = semakptr->u.__sem_base - sem + semakptr->u.sem_nsems;
585 i < semtot; i++)
586 sem[i - semakptr->u.sem_nsems] = sem[i];
587 for (i = 0; i < seminfo.semmni; i++) {
588 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) &&
589 sema[i].u.__sem_base > semakptr->u.__sem_base) {
590 sema[i].u.__sem_base -= semakptr->u.sem_nsems;
591 mtx_unlock(&sema_mtx[i]);
592 }
593 }
594 semtot -= semakptr->u.sem_nsems;
595 }
596
597 static struct prison *
sem_find_prison(struct ucred * cred)598 sem_find_prison(struct ucred *cred)
599 {
600 struct prison *pr, *rpr;
601
602 pr = cred->cr_prison;
603 prison_lock(pr);
604 rpr = osd_jail_get(pr, sem_prison_slot);
605 prison_unlock(pr);
606 return (rpr);
607 }
608
609 static int
sem_prison_cansee(struct prison * rpr,struct semid_kernel * semakptr)610 sem_prison_cansee(struct prison *rpr, struct semid_kernel *semakptr)
611 {
612
613 if (semakptr->cred == NULL ||
614 !(rpr == semakptr->cred->cr_prison ||
615 prison_ischild(rpr, semakptr->cred->cr_prison)))
616 return (EINVAL);
617 return (0);
618 }
619
620 /*
621 * Note that the user-mode half of this passes a union, not a pointer.
622 */
623 #ifndef _SYS_SYSPROTO_H_
624 struct __semctl_args {
625 int semid;
626 int semnum;
627 int cmd;
628 union semun *arg;
629 };
630 #endif
631 int
sys___semctl(struct thread * td,struct __semctl_args * uap)632 sys___semctl(struct thread *td, struct __semctl_args *uap)
633 {
634 struct semid_ds dsbuf;
635 union semun arg, semun;
636 register_t rval;
637 int error;
638
639 switch (uap->cmd) {
640 case SEM_STAT:
641 case IPC_SET:
642 case IPC_STAT:
643 case GETALL:
644 case SETVAL:
645 case SETALL:
646 error = copyin(uap->arg, &arg, sizeof(arg));
647 if (error)
648 return (error);
649 break;
650 }
651
652 switch (uap->cmd) {
653 case SEM_STAT:
654 case IPC_STAT:
655 semun.buf = &dsbuf;
656 break;
657 case IPC_SET:
658 error = copyin(arg.buf, &dsbuf, sizeof(dsbuf));
659 if (error)
660 return (error);
661 semun.buf = &dsbuf;
662 break;
663 case GETALL:
664 case SETALL:
665 semun.array = arg.array;
666 break;
667 case SETVAL:
668 semun.val = arg.val;
669 break;
670 }
671
672 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun,
673 &rval);
674 if (error)
675 return (error);
676
677 switch (uap->cmd) {
678 case SEM_STAT:
679 case IPC_STAT:
680 error = copyout(&dsbuf, arg.buf, sizeof(dsbuf));
681 break;
682 }
683
684 if (error == 0)
685 td->td_retval[0] = rval;
686 return (error);
687 }
688
689 int
kern_semctl(struct thread * td,int semid,int semnum,int cmd,union semun * arg,register_t * rval)690 kern_semctl(struct thread *td, int semid, int semnum, int cmd,
691 union semun *arg, register_t *rval)
692 {
693 u_short *array;
694 struct ucred *cred = td->td_ucred;
695 int i, error;
696 struct prison *rpr;
697 struct semid_ds *sbuf;
698 struct semid_kernel *semakptr;
699 struct mtx *sema_mtxp;
700 u_short usval, count;
701 int semidx;
702
703 DPRINTF(("call to semctl(%d, %d, %d, 0x%p)\n",
704 semid, semnum, cmd, arg));
705
706 AUDIT_ARG_SVIPC_CMD(cmd);
707 AUDIT_ARG_SVIPC_ID(semid);
708
709 rpr = sem_find_prison(td->td_ucred);
710 if (rpr == NULL)
711 return (ENOSYS);
712
713 array = NULL;
714
715 switch(cmd) {
716 case SEM_STAT:
717 /*
718 * For this command we assume semid is an array index
719 * rather than an IPC id.
720 */
721 if (semid < 0 || semid >= seminfo.semmni)
722 return (EINVAL);
723 semakptr = &sema[semid];
724 sema_mtxp = &sema_mtx[semid];
725 mtx_lock(sema_mtxp);
726 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0) {
727 error = EINVAL;
728 goto done2;
729 }
730 if ((error = sem_prison_cansee(rpr, semakptr)))
731 goto done2;
732 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R)))
733 goto done2;
734 #ifdef MAC
735 error = mac_sysvsem_check_semctl(cred, semakptr, cmd);
736 if (error != 0)
737 goto done2;
738 #endif
739 bcopy(&semakptr->u, arg->buf, sizeof(struct semid_ds));
740 if (cred->cr_prison != semakptr->cred->cr_prison)
741 arg->buf->sem_perm.key = IPC_PRIVATE;
742 *rval = IXSEQ_TO_IPCID(semid, semakptr->u.sem_perm);
743 mtx_unlock(sema_mtxp);
744 return (0);
745 }
746
747 semidx = IPCID_TO_IX(semid);
748 if (semidx < 0 || semidx >= seminfo.semmni)
749 return (EINVAL);
750
751 semakptr = &sema[semidx];
752 sema_mtxp = &sema_mtx[semidx];
753 if (cmd == IPC_RMID)
754 mtx_lock(&sem_mtx);
755 mtx_lock(sema_mtxp);
756
757 #ifdef MAC
758 error = mac_sysvsem_check_semctl(cred, semakptr, cmd);
759 if (error != 0)
760 goto done2;
761 #endif
762
763 error = 0;
764 *rval = 0;
765
766 switch (cmd) {
767 case IPC_RMID:
768 if ((error = semvalid(semid, rpr, semakptr)) != 0)
769 goto done2;
770 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_M)))
771 goto done2;
772 sem_remove(semidx, cred);
773 break;
774
775 case IPC_SET:
776 AUDIT_ARG_SVIPC_PERM(&arg->buf->sem_perm);
777 if ((error = semvalid(semid, rpr, semakptr)) != 0)
778 goto done2;
779 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_M)))
780 goto done2;
781 sbuf = arg->buf;
782 semakptr->u.sem_perm.uid = sbuf->sem_perm.uid;
783 semakptr->u.sem_perm.gid = sbuf->sem_perm.gid;
784 semakptr->u.sem_perm.mode = (semakptr->u.sem_perm.mode &
785 ~0777) | (sbuf->sem_perm.mode & 0777);
786 semakptr->u.sem_ctime = time_second;
787 break;
788
789 case IPC_STAT:
790 if ((error = semvalid(semid, rpr, semakptr)) != 0)
791 goto done2;
792 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R)))
793 goto done2;
794 bcopy(&semakptr->u, arg->buf, sizeof(struct semid_ds));
795 if (cred->cr_prison != semakptr->cred->cr_prison)
796 arg->buf->sem_perm.key = IPC_PRIVATE;
797
798 /*
799 * Try to hide the fact that the structure layout is shared by
800 * both the kernel and userland. This pointer is not useful to
801 * userspace.
802 */
803 arg->buf->__sem_base = NULL;
804 break;
805
806 case GETNCNT:
807 if ((error = semvalid(semid, rpr, semakptr)) != 0)
808 goto done2;
809 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R)))
810 goto done2;
811 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
812 error = EINVAL;
813 goto done2;
814 }
815 *rval = semakptr->u.__sem_base[semnum].semncnt;
816 break;
817
818 case GETPID:
819 if ((error = semvalid(semid, rpr, semakptr)) != 0)
820 goto done2;
821 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R)))
822 goto done2;
823 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
824 error = EINVAL;
825 goto done2;
826 }
827 *rval = semakptr->u.__sem_base[semnum].sempid;
828 break;
829
830 case GETVAL:
831 if ((error = semvalid(semid, rpr, semakptr)) != 0)
832 goto done2;
833 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R)))
834 goto done2;
835 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
836 error = EINVAL;
837 goto done2;
838 }
839 *rval = semakptr->u.__sem_base[semnum].semval;
840 break;
841
842 case GETALL:
843 /*
844 * Unfortunately, callers of this function don't know
845 * in advance how many semaphores are in this set.
846 * While we could just allocate the maximum size array
847 * and pass the actual size back to the caller, that
848 * won't work for SETALL since we can't copyin() more
849 * data than the user specified as we may return a
850 * spurious EFAULT.
851 */
852 if ((error = semvalid(semid, rpr, semakptr)) != 0)
853 goto done2;
854 count = semakptr->u.sem_nsems;
855 mtx_unlock(sema_mtxp);
856 array = malloc(sizeof(*array) * count, M_TEMP, M_WAITOK);
857 mtx_lock(sema_mtxp);
858 if ((error = semvalid(semid, rpr, semakptr)) != 0)
859 goto done2;
860 if (count != semakptr->u.sem_nsems) {
861 /* Unlikely, but possible. */
862 error = EAGAIN;
863 goto done2;
864 }
865 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R)))
866 goto done2;
867 for (i = 0; i < semakptr->u.sem_nsems; i++)
868 array[i] = semakptr->u.__sem_base[i].semval;
869 mtx_unlock(sema_mtxp);
870 error = copyout(array, arg->array, count * sizeof(*array));
871 mtx_lock(sema_mtxp);
872 break;
873
874 case GETZCNT:
875 if ((error = semvalid(semid, rpr, semakptr)) != 0)
876 goto done2;
877 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R)))
878 goto done2;
879 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
880 error = EINVAL;
881 goto done2;
882 }
883 *rval = semakptr->u.__sem_base[semnum].semzcnt;
884 break;
885
886 case SETVAL:
887 if ((error = semvalid(semid, rpr, semakptr)) != 0)
888 goto done2;
889 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_W)))
890 goto done2;
891 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) {
892 error = EINVAL;
893 goto done2;
894 }
895 if (arg->val < 0 || arg->val > seminfo.semvmx) {
896 error = ERANGE;
897 goto done2;
898 }
899 semakptr->u.__sem_base[semnum].semval = arg->val;
900 SEMUNDO_LOCK();
901 semundo_clear(semidx, semnum);
902 SEMUNDO_UNLOCK();
903 wakeup(semakptr);
904 break;
905
906 case SETALL:
907 if ((error = semvalid(semid, rpr, semakptr)) != 0)
908 goto done2;
909 count = semakptr->u.sem_nsems;
910 mtx_unlock(sema_mtxp);
911 array = malloc(sizeof(*array) * count, M_TEMP, M_WAITOK);
912 error = copyin(arg->array, array, count * sizeof(*array));
913 mtx_lock(sema_mtxp);
914 if (error)
915 break;
916 if ((error = semvalid(semid, rpr, semakptr)) != 0)
917 goto done2;
918 if (count != semakptr->u.sem_nsems) {
919 /* Unlikely, but possible. */
920 error = EAGAIN;
921 goto done2;
922 }
923 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_W)))
924 goto done2;
925 for (i = 0; i < semakptr->u.sem_nsems; i++) {
926 usval = array[i];
927 if (usval > seminfo.semvmx) {
928 error = ERANGE;
929 break;
930 }
931 semakptr->u.__sem_base[i].semval = usval;
932 }
933 SEMUNDO_LOCK();
934 semundo_clear(semidx, -1);
935 SEMUNDO_UNLOCK();
936 wakeup(semakptr);
937 break;
938
939 default:
940 error = EINVAL;
941 break;
942 }
943
944 done2:
945 mtx_unlock(sema_mtxp);
946 if (cmd == IPC_RMID)
947 mtx_unlock(&sem_mtx);
948 if (array != NULL)
949 free(array, M_TEMP);
950 return(error);
951 }
952
953 #ifndef _SYS_SYSPROTO_H_
954 struct semget_args {
955 key_t key;
956 int nsems;
957 int semflg;
958 };
959 #endif
960 int
sys_semget(struct thread * td,struct semget_args * uap)961 sys_semget(struct thread *td, struct semget_args *uap)
962 {
963 int semid, error = 0;
964 int key = uap->key;
965 int nsems = uap->nsems;
966 int semflg = uap->semflg;
967 struct ucred *cred = td->td_ucred;
968
969 DPRINTF(("semget(0x%x, %d, 0%o)\n", key, nsems, semflg));
970
971 AUDIT_ARG_VALUE(semflg);
972
973 if (sem_find_prison(cred) == NULL)
974 return (ENOSYS);
975
976 mtx_lock(&sem_mtx);
977 if (key != IPC_PRIVATE) {
978 for (semid = 0; semid < seminfo.semmni; semid++) {
979 if ((sema[semid].u.sem_perm.mode & SEM_ALLOC) &&
980 sema[semid].cred != NULL &&
981 sema[semid].cred->cr_prison == cred->cr_prison &&
982 sema[semid].u.sem_perm.key == key)
983 break;
984 }
985 if (semid < seminfo.semmni) {
986 AUDIT_ARG_SVIPC_ID(semid);
987 DPRINTF(("found public key\n"));
988 if ((semflg & IPC_CREAT) && (semflg & IPC_EXCL)) {
989 DPRINTF(("not exclusive\n"));
990 error = EEXIST;
991 goto done2;
992 }
993 if ((error = ipcperm(td, &sema[semid].u.sem_perm,
994 semflg & 0700))) {
995 goto done2;
996 }
997 if (nsems > 0 && sema[semid].u.sem_nsems < nsems) {
998 DPRINTF(("too small\n"));
999 error = EINVAL;
1000 goto done2;
1001 }
1002 #ifdef MAC
1003 error = mac_sysvsem_check_semget(cred, &sema[semid]);
1004 if (error != 0)
1005 goto done2;
1006 #endif
1007 goto found;
1008 }
1009 }
1010
1011 DPRINTF(("need to allocate the semid_kernel\n"));
1012 if (key == IPC_PRIVATE || (semflg & IPC_CREAT)) {
1013 if (nsems <= 0 || nsems > seminfo.semmsl) {
1014 DPRINTF(("nsems out of range (0<%d<=%d)\n", nsems,
1015 seminfo.semmsl));
1016 error = EINVAL;
1017 goto done2;
1018 }
1019 if (nsems > seminfo.semmns - semtot) {
1020 DPRINTF((
1021 "not enough semaphores left (need %d, got %d)\n",
1022 nsems, seminfo.semmns - semtot));
1023 error = ENOSPC;
1024 goto done2;
1025 }
1026 for (semid = 0; semid < seminfo.semmni; semid++) {
1027 if ((sema[semid].u.sem_perm.mode & SEM_ALLOC) == 0)
1028 break;
1029 }
1030 if (semid == seminfo.semmni) {
1031 DPRINTF(("no more semid_kernel's available\n"));
1032 error = ENOSPC;
1033 goto done2;
1034 }
1035 #ifdef RACCT
1036 if (racct_enable) {
1037 PROC_LOCK(td->td_proc);
1038 error = racct_add(td->td_proc, RACCT_NSEM, nsems);
1039 PROC_UNLOCK(td->td_proc);
1040 if (error != 0) {
1041 error = ENOSPC;
1042 goto done2;
1043 }
1044 }
1045 #endif
1046 DPRINTF(("semid %d is available\n", semid));
1047 mtx_lock(&sema_mtx[semid]);
1048 KASSERT((sema[semid].u.sem_perm.mode & SEM_ALLOC) == 0,
1049 ("Lost semaphore %d", semid));
1050 sema[semid].u.sem_perm.key = key;
1051 sema[semid].u.sem_perm.cuid = cred->cr_uid;
1052 sema[semid].u.sem_perm.uid = cred->cr_uid;
1053 sema[semid].u.sem_perm.cgid = cred->cr_gid;
1054 sema[semid].u.sem_perm.gid = cred->cr_gid;
1055 sema[semid].u.sem_perm.mode = (semflg & 0777) | SEM_ALLOC;
1056 sema[semid].cred = crhold(cred);
1057 sema[semid].u.sem_perm.seq =
1058 (sema[semid].u.sem_perm.seq + 1) & 0x7fff;
1059 sema[semid].u.sem_nsems = nsems;
1060 sema[semid].u.sem_otime = 0;
1061 sema[semid].u.sem_ctime = time_second;
1062 sema[semid].u.__sem_base = &sem[semtot];
1063 semtot += nsems;
1064 bzero(sema[semid].u.__sem_base,
1065 sizeof(sema[semid].u.__sem_base[0])*nsems);
1066 #ifdef MAC
1067 mac_sysvsem_create(cred, &sema[semid]);
1068 #endif
1069 mtx_unlock(&sema_mtx[semid]);
1070 DPRINTF(("sembase = %p, next = %p\n",
1071 sema[semid].u.__sem_base, &sem[semtot]));
1072 } else {
1073 DPRINTF(("didn't find it and wasn't asked to create it\n"));
1074 error = ENOENT;
1075 goto done2;
1076 }
1077
1078 found:
1079 td->td_retval[0] = IXSEQ_TO_IPCID(semid, sema[semid].u.sem_perm);
1080 done2:
1081 mtx_unlock(&sem_mtx);
1082 return (error);
1083 }
1084
1085 #ifndef _SYS_SYSPROTO_H_
1086 struct semop_args {
1087 int semid;
1088 struct sembuf *sops;
1089 size_t nsops;
1090 };
1091 #endif
1092 int
sys_semop(struct thread * td,struct semop_args * uap)1093 sys_semop(struct thread *td, struct semop_args *uap)
1094 {
1095
1096 return (kern_semop(td, uap->semid, uap->sops, uap->nsops, NULL));
1097 }
1098
1099 int
kern_semop(struct thread * td,int usemid,struct sembuf * usops,size_t nsops,struct timespec * timeout)1100 kern_semop(struct thread *td, int usemid, struct sembuf *usops,
1101 size_t nsops, struct timespec *timeout)
1102 {
1103 #define SMALL_SOPS 8
1104 struct sembuf small_sops[SMALL_SOPS];
1105 int semid;
1106 struct prison *rpr;
1107 struct sembuf *sops;
1108 struct semid_kernel *semakptr;
1109 struct sembuf *sopptr = NULL;
1110 struct sem *semptr = NULL;
1111 struct sem_undo *suptr;
1112 struct mtx *sema_mtxp;
1113 sbintime_t sbt, precision;
1114 size_t i, j, k;
1115 int error;
1116 int do_wakeup, do_undos;
1117 unsigned short seq;
1118
1119 #ifdef SEM_DEBUG
1120 sops = NULL;
1121 #endif
1122 DPRINTF(("call to semop(%d, %p, %u)\n", usemid, usops, nsops));
1123
1124 AUDIT_ARG_SVIPC_ID(usemid);
1125
1126 rpr = sem_find_prison(td->td_ucred);
1127 if (rpr == NULL)
1128 return (ENOSYS);
1129
1130 semid = IPCID_TO_IX(usemid); /* Convert back to zero origin */
1131
1132 if (semid < 0 || semid >= seminfo.semmni)
1133 return (EINVAL);
1134 if (timeout != NULL) {
1135 if (!timespecvalid_interval(timeout))
1136 return (EINVAL);
1137 precision = 0;
1138 if (timespecisset(timeout)) {
1139 if (timeout->tv_sec < INT32_MAX / 2) {
1140 precision = tstosbt(*timeout);
1141 if (TIMESEL(&sbt, precision))
1142 sbt += tc_tick_sbt;
1143 sbt += precision;
1144 precision >>= tc_precexp;
1145 } else
1146 sbt = 0;
1147 } else
1148 sbt = -1;
1149 } else
1150 precision = sbt = 0;
1151
1152 /* Allocate memory for sem_ops */
1153 if (nsops <= SMALL_SOPS)
1154 sops = small_sops;
1155 else if (nsops > seminfo.semopm) {
1156 DPRINTF(("too many sops (max=%d, nsops=%d)\n", seminfo.semopm,
1157 nsops));
1158 return (E2BIG);
1159 } else {
1160 #ifdef RACCT
1161 if (racct_enable) {
1162 PROC_LOCK(td->td_proc);
1163 if (nsops >
1164 racct_get_available(td->td_proc, RACCT_NSEMOP)) {
1165 PROC_UNLOCK(td->td_proc);
1166 return (E2BIG);
1167 }
1168 PROC_UNLOCK(td->td_proc);
1169 }
1170 #endif
1171
1172 sops = malloc(nsops * sizeof(*sops), M_TEMP, M_WAITOK);
1173 }
1174 if ((error = copyin(usops, sops, nsops * sizeof(sops[0]))) != 0) {
1175 DPRINTF(("error = %d from copyin(%p, %p, %d)\n", error,
1176 usops, sops, nsops * sizeof(sops[0])));
1177 if (sops != small_sops)
1178 free(sops, M_TEMP);
1179 return (error);
1180 }
1181
1182 semakptr = &sema[semid];
1183 sema_mtxp = &sema_mtx[semid];
1184 mtx_lock(sema_mtxp);
1185 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0) {
1186 error = EINVAL;
1187 goto done2;
1188 }
1189 seq = semakptr->u.sem_perm.seq;
1190 if (seq != IPCID_TO_SEQ(usemid)) {
1191 error = EINVAL;
1192 goto done2;
1193 }
1194 if ((error = sem_prison_cansee(rpr, semakptr)) != 0)
1195 goto done2;
1196 /*
1197 * Initial pass through sops to see what permissions are needed.
1198 * Also perform any checks that don't need repeating on each
1199 * attempt to satisfy the request vector.
1200 */
1201 j = 0; /* permission needed */
1202 do_undos = 0;
1203 for (i = 0; i < nsops; i++) {
1204 sopptr = &sops[i];
1205 if (sopptr->sem_num >= semakptr->u.sem_nsems) {
1206 error = EFBIG;
1207 goto done2;
1208 }
1209 if (sopptr->sem_flg & SEM_UNDO && sopptr->sem_op != 0)
1210 do_undos = 1;
1211 j |= (sopptr->sem_op == 0) ? SEM_R : SEM_A;
1212 }
1213
1214 if ((error = ipcperm(td, &semakptr->u.sem_perm, j))) {
1215 DPRINTF(("error = %d from ipaccess\n", error));
1216 goto done2;
1217 }
1218 #ifdef MAC
1219 error = mac_sysvsem_check_semop(td->td_ucred, semakptr, j);
1220 if (error != 0)
1221 goto done2;
1222 #endif
1223
1224 /*
1225 * Loop trying to satisfy the vector of requests.
1226 * If we reach a point where we must wait, any requests already
1227 * performed are rolled back and we go to sleep until some other
1228 * process wakes us up. At this point, we start all over again.
1229 *
1230 * This ensures that from the perspective of other tasks, a set
1231 * of requests is atomic (never partially satisfied).
1232 */
1233 for (;;) {
1234 do_wakeup = 0;
1235 error = 0; /* error return if necessary */
1236
1237 for (i = 0; i < nsops; i++) {
1238 sopptr = &sops[i];
1239 semptr = &semakptr->u.__sem_base[sopptr->sem_num];
1240
1241 DPRINTF((
1242 "semop: semakptr=%p, __sem_base=%p, "
1243 "semptr=%p, sem[%d]=%d : op=%d, flag=%s\n",
1244 semakptr, semakptr->u.__sem_base, semptr,
1245 sopptr->sem_num, semptr->semval, sopptr->sem_op,
1246 (sopptr->sem_flg & IPC_NOWAIT) ?
1247 "nowait" : "wait"));
1248
1249 if (sopptr->sem_op < 0) {
1250 if (semptr->semval + sopptr->sem_op < 0) {
1251 DPRINTF(("semop: can't do it now\n"));
1252 break;
1253 } else {
1254 semptr->semval += sopptr->sem_op;
1255 if (semptr->semval == 0 &&
1256 semptr->semzcnt > 0)
1257 do_wakeup = 1;
1258 }
1259 } else if (sopptr->sem_op == 0) {
1260 if (semptr->semval != 0) {
1261 DPRINTF(("semop: not zero now\n"));
1262 break;
1263 }
1264 } else if (semptr->semval + sopptr->sem_op >
1265 seminfo.semvmx) {
1266 error = ERANGE;
1267 break;
1268 } else {
1269 if (semptr->semncnt > 0)
1270 do_wakeup = 1;
1271 semptr->semval += sopptr->sem_op;
1272 }
1273 }
1274
1275 /*
1276 * Did we get through the entire vector?
1277 */
1278 if (i >= nsops)
1279 goto done;
1280
1281 /*
1282 * No ... rollback anything that we've already done
1283 */
1284 DPRINTF(("semop: rollback 0 through %d\n", i-1));
1285 for (j = 0; j < i; j++)
1286 semakptr->u.__sem_base[sops[j].sem_num].semval -=
1287 sops[j].sem_op;
1288
1289 /* If we detected an error, return it */
1290 if (error != 0)
1291 goto done2;
1292
1293 /*
1294 * If the request that we couldn't satisfy has the
1295 * NOWAIT flag set then return with EAGAIN.
1296 */
1297 if (sopptr->sem_flg & IPC_NOWAIT) {
1298 error = EAGAIN;
1299 goto done2;
1300 }
1301
1302 if (sopptr->sem_op == 0)
1303 semptr->semzcnt++;
1304 else
1305 semptr->semncnt++;
1306
1307 DPRINTF(("semop: good night!\n"));
1308 error = msleep_sbt(semakptr, sema_mtxp, PVFS | PCATCH,
1309 "semwait", sbt, precision, C_ABSOLUTE);
1310 DPRINTF(("semop: good morning (error=%d)!\n", error));
1311 /* return code is checked below, after sem[nz]cnt-- */
1312
1313 /*
1314 * Make sure that the semaphore still exists
1315 */
1316 seq = semakptr->u.sem_perm.seq;
1317 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 ||
1318 seq != IPCID_TO_SEQ(usemid)) {
1319 error = EIDRM;
1320 goto done2;
1321 }
1322
1323 /*
1324 * Renew the semaphore's pointer after wakeup since
1325 * during msleep __sem_base may have been modified and semptr
1326 * is not valid any more
1327 */
1328 semptr = &semakptr->u.__sem_base[sopptr->sem_num];
1329
1330 /*
1331 * The semaphore is still alive. Readjust the count of
1332 * waiting processes.
1333 */
1334 if (sopptr->sem_op == 0)
1335 semptr->semzcnt--;
1336 else
1337 semptr->semncnt--;
1338
1339 /*
1340 * Is it really morning, or was our sleep interrupted?
1341 * (Delayed check of msleep() return code because we
1342 * need to decrement sem[nz]cnt either way.)
1343 */
1344 if (error != 0) {
1345 if (error == ERESTART)
1346 error = EINTR;
1347 goto done2;
1348 }
1349 DPRINTF(("semop: good morning!\n"));
1350 }
1351
1352 done:
1353 /*
1354 * Process any SEM_UNDO requests.
1355 */
1356 if (do_undos) {
1357 SEMUNDO_LOCK();
1358 suptr = NULL;
1359 for (i = 0; i < nsops; i++) {
1360 /*
1361 * We only need to deal with SEM_UNDO's for non-zero
1362 * op's.
1363 */
1364 int adjval;
1365
1366 if ((sops[i].sem_flg & SEM_UNDO) == 0)
1367 continue;
1368 adjval = sops[i].sem_op;
1369 if (adjval == 0)
1370 continue;
1371 error = semundo_adjust(td, &suptr, semid, seq,
1372 sops[i].sem_num, -adjval);
1373 if (error == 0)
1374 continue;
1375
1376 /*
1377 * Oh-Oh! We ran out of either sem_undo's or undo's.
1378 * Rollback the adjustments to this point and then
1379 * rollback the semaphore ups and down so we can return
1380 * with an error with all structures restored. We
1381 * rollback the undo's in the exact reverse order that
1382 * we applied them. This guarantees that we won't run
1383 * out of space as we roll things back out.
1384 */
1385 for (j = 0; j < i; j++) {
1386 k = i - j - 1;
1387 if ((sops[k].sem_flg & SEM_UNDO) == 0)
1388 continue;
1389 adjval = sops[k].sem_op;
1390 if (adjval == 0)
1391 continue;
1392 if (semundo_adjust(td, &suptr, semid, seq,
1393 sops[k].sem_num, adjval) != 0)
1394 panic("semop - can't undo undos");
1395 }
1396
1397 for (j = 0; j < nsops; j++)
1398 semakptr->u.__sem_base[sops[j].sem_num].semval -=
1399 sops[j].sem_op;
1400
1401 DPRINTF(("error = %d from semundo_adjust\n", error));
1402 SEMUNDO_UNLOCK();
1403 goto done2;
1404 } /* loop through the sops */
1405 SEMUNDO_UNLOCK();
1406 } /* if (do_undos) */
1407
1408 /* We're definitely done - set the sempid's and time */
1409 for (i = 0; i < nsops; i++) {
1410 sopptr = &sops[i];
1411 semptr = &semakptr->u.__sem_base[sopptr->sem_num];
1412 semptr->sempid = td->td_proc->p_pid;
1413 }
1414 semakptr->u.sem_otime = time_second;
1415
1416 /*
1417 * Do a wakeup if any semaphore was up'd whilst something was
1418 * sleeping on it.
1419 */
1420 if (do_wakeup) {
1421 DPRINTF(("semop: doing wakeup\n"));
1422 wakeup(semakptr);
1423 DPRINTF(("semop: back from wakeup\n"));
1424 }
1425 DPRINTF(("semop: done\n"));
1426 td->td_retval[0] = 0;
1427 done2:
1428 mtx_unlock(sema_mtxp);
1429 if (sops != small_sops)
1430 free(sops, M_TEMP);
1431 return (error);
1432 }
1433
1434 /*
1435 * Go through the undo structures for this process and apply the adjustments to
1436 * semaphores.
1437 */
1438 static void
semexit_myhook(void * arg,struct proc * p)1439 semexit_myhook(void *arg, struct proc *p)
1440 {
1441 struct sem_undo *suptr;
1442 struct semid_kernel *semakptr;
1443 struct mtx *sema_mtxp;
1444 int semid, semnum, adjval, ix;
1445 unsigned short seq;
1446
1447 /*
1448 * Go through the chain of undo vectors looking for one
1449 * associated with this process.
1450 */
1451 if (LIST_EMPTY(&semu_list))
1452 return;
1453 SEMUNDO_LOCK();
1454 LIST_FOREACH(suptr, &semu_list, un_next) {
1455 if (suptr->un_proc == p)
1456 break;
1457 }
1458 if (suptr == NULL) {
1459 SEMUNDO_UNLOCK();
1460 return;
1461 }
1462 LIST_REMOVE(suptr, un_next);
1463
1464 DPRINTF(("proc @%p has undo structure with %d entries\n", p,
1465 suptr->un_cnt));
1466
1467 /*
1468 * If there are any active undo elements then process them.
1469 */
1470 if (suptr->un_cnt > 0) {
1471 SEMUNDO_UNLOCK();
1472 for (ix = 0; ix < suptr->un_cnt; ix++) {
1473 semid = suptr->un_ent[ix].un_id;
1474 semnum = suptr->un_ent[ix].un_num;
1475 adjval = suptr->un_ent[ix].un_adjval;
1476 seq = suptr->un_ent[ix].un_seq;
1477 semakptr = &sema[semid];
1478 sema_mtxp = &sema_mtx[semid];
1479
1480 mtx_lock(sema_mtxp);
1481 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 ||
1482 semakptr->u.sem_perm.seq != seq ||
1483 semakptr->u.sem_nsems <= semnum) {
1484 mtx_unlock(sema_mtxp);
1485 continue;
1486 }
1487
1488 DPRINTF((
1489 "semexit: %p id=%d num=%d(adj=%d) ; sem=%d\n",
1490 suptr->un_proc, suptr->un_ent[ix].un_id,
1491 suptr->un_ent[ix].un_num,
1492 suptr->un_ent[ix].un_adjval,
1493 semakptr->u.__sem_base[semnum].semval));
1494
1495 if (adjval < 0 && semakptr->u.__sem_base[semnum].semval <
1496 -adjval)
1497 semakptr->u.__sem_base[semnum].semval = 0;
1498 else
1499 semakptr->u.__sem_base[semnum].semval += adjval;
1500
1501 wakeup(semakptr);
1502 DPRINTF(("semexit: back from wakeup\n"));
1503 mtx_unlock(sema_mtxp);
1504 }
1505 SEMUNDO_LOCK();
1506 }
1507
1508 /*
1509 * Deallocate the undo vector.
1510 */
1511 DPRINTF(("removing vector\n"));
1512 suptr->un_proc = NULL;
1513 suptr->un_cnt = 0;
1514 LIST_INSERT_HEAD(&semu_free_list, suptr, un_next);
1515 SEMUNDO_UNLOCK();
1516 }
1517
1518 static int
sysctl_sema(SYSCTL_HANDLER_ARGS)1519 sysctl_sema(SYSCTL_HANDLER_ARGS)
1520 {
1521 struct prison *pr, *rpr;
1522 struct semid_kernel tsemak;
1523 #ifdef COMPAT_FREEBSD32
1524 struct semid_kernel32 tsemak32;
1525 #endif
1526 void *outaddr;
1527 size_t outsize;
1528 int error, i;
1529
1530 pr = req->td->td_ucred->cr_prison;
1531 rpr = sem_find_prison(req->td->td_ucred);
1532 error = 0;
1533 for (i = 0; i < seminfo.semmni; i++) {
1534 mtx_lock(&sema_mtx[i]);
1535 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) == 0 ||
1536 rpr == NULL || sem_prison_cansee(rpr, &sema[i]) != 0)
1537 bzero(&tsemak, sizeof(tsemak));
1538 else {
1539 tsemak = sema[i];
1540 if (tsemak.cred->cr_prison != pr)
1541 tsemak.u.sem_perm.key = IPC_PRIVATE;
1542 }
1543 mtx_unlock(&sema_mtx[i]);
1544 #ifdef COMPAT_FREEBSD32
1545 if (SV_CURPROC_FLAG(SV_ILP32)) {
1546 bzero(&tsemak32, sizeof(tsemak32));
1547 freebsd32_ipcperm_out(&tsemak.u.sem_perm,
1548 &tsemak32.u.sem_perm);
1549 /* Don't copy u.__sem_base */
1550 CP(tsemak, tsemak32, u.sem_nsems);
1551 CP(tsemak, tsemak32, u.sem_otime);
1552 CP(tsemak, tsemak32, u.sem_ctime);
1553 /* Don't copy label or cred */
1554 outaddr = &tsemak32;
1555 outsize = sizeof(tsemak32);
1556 } else
1557 #endif
1558 {
1559 tsemak.u.__sem_base = NULL;
1560 tsemak.label = NULL;
1561 tsemak.cred = NULL;
1562 outaddr = &tsemak;
1563 outsize = sizeof(tsemak);
1564 }
1565 error = SYSCTL_OUT(req, outaddr, outsize);
1566 if (error != 0)
1567 break;
1568 }
1569 return (error);
1570 }
1571
1572 int
kern_get_sema(struct thread * td,struct semid_kernel ** res,size_t * sz)1573 kern_get_sema(struct thread *td, struct semid_kernel **res, size_t *sz)
1574 {
1575 struct prison *pr, *rpr;
1576 struct semid_kernel *psemak;
1577 int i, mi;
1578
1579 *sz = mi = seminfo.semmni;
1580 if (res == NULL)
1581 return (0);
1582
1583 pr = td->td_ucred->cr_prison;
1584 rpr = sem_find_prison(td->td_ucred);
1585 *res = malloc(sizeof(struct semid_kernel) * mi, M_TEMP, M_WAITOK);
1586 for (i = 0; i < mi; i++) {
1587 psemak = &(*res)[i];
1588 mtx_lock(&sema_mtx[i]);
1589 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) == 0 ||
1590 rpr == NULL || sem_prison_cansee(rpr, &sema[i]) != 0)
1591 bzero(psemak, sizeof(*psemak));
1592 else {
1593 *psemak = sema[i];
1594 if (psemak->cred->cr_prison != pr)
1595 psemak->u.sem_perm.key = IPC_PRIVATE;
1596 }
1597 mtx_unlock(&sema_mtx[i]);
1598 psemak->u.__sem_base = NULL;
1599 psemak->label = NULL;
1600 psemak->cred = NULL;
1601 }
1602 return (0);
1603 }
1604
1605 static int
sem_prison_check(void * obj,void * data)1606 sem_prison_check(void *obj, void *data)
1607 {
1608 struct prison *pr = obj;
1609 struct prison *prpr;
1610 struct vfsoptlist *opts = data;
1611 int error, jsys;
1612
1613 /*
1614 * sysvsem is a jailsys integer.
1615 * It must be "disable" if the parent jail is disabled.
1616 */
1617 error = vfs_copyopt(opts, "sysvsem", &jsys, sizeof(jsys));
1618 if (error != ENOENT) {
1619 if (error != 0)
1620 return (error);
1621 switch (jsys) {
1622 case JAIL_SYS_DISABLE:
1623 break;
1624 case JAIL_SYS_NEW:
1625 case JAIL_SYS_INHERIT:
1626 prison_lock(pr->pr_parent);
1627 prpr = osd_jail_get(pr->pr_parent, sem_prison_slot);
1628 prison_unlock(pr->pr_parent);
1629 if (prpr == NULL)
1630 return (EPERM);
1631 break;
1632 default:
1633 return (EINVAL);
1634 }
1635 }
1636
1637 return (0);
1638 }
1639
1640 static int
sem_prison_set(void * obj,void * data)1641 sem_prison_set(void *obj, void *data)
1642 {
1643 struct prison *pr = obj;
1644 struct prison *tpr, *orpr, *nrpr, *trpr;
1645 struct vfsoptlist *opts = data;
1646 void *rsv;
1647 int jsys, descend;
1648
1649 /*
1650 * sysvsem controls which jail is the root of the associated sems (this
1651 * jail or same as the parent), or if the feature is available at all.
1652 */
1653 if (vfs_copyopt(opts, "sysvsem", &jsys, sizeof(jsys)) == ENOENT)
1654 jsys = vfs_flagopt(opts, "allow.sysvipc", NULL, 0)
1655 ? JAIL_SYS_INHERIT
1656 : vfs_flagopt(opts, "allow.nosysvipc", NULL, 0)
1657 ? JAIL_SYS_DISABLE
1658 : -1;
1659 if (jsys == JAIL_SYS_DISABLE) {
1660 prison_lock(pr);
1661 orpr = osd_jail_get(pr, sem_prison_slot);
1662 if (orpr != NULL)
1663 osd_jail_del(pr, sem_prison_slot);
1664 prison_unlock(pr);
1665 if (orpr != NULL) {
1666 if (orpr == pr)
1667 sem_prison_cleanup(pr);
1668 /* Disable all child jails as well. */
1669 FOREACH_PRISON_DESCENDANT(pr, tpr, descend) {
1670 prison_lock(tpr);
1671 trpr = osd_jail_get(tpr, sem_prison_slot);
1672 if (trpr != NULL) {
1673 osd_jail_del(tpr, sem_prison_slot);
1674 prison_unlock(tpr);
1675 if (trpr == tpr)
1676 sem_prison_cleanup(tpr);
1677 } else {
1678 prison_unlock(tpr);
1679 descend = 0;
1680 }
1681 }
1682 }
1683 } else if (jsys != -1) {
1684 if (jsys == JAIL_SYS_NEW)
1685 nrpr = pr;
1686 else {
1687 prison_lock(pr->pr_parent);
1688 nrpr = osd_jail_get(pr->pr_parent, sem_prison_slot);
1689 prison_unlock(pr->pr_parent);
1690 }
1691 rsv = osd_reserve(sem_prison_slot);
1692 prison_lock(pr);
1693 orpr = osd_jail_get(pr, sem_prison_slot);
1694 if (orpr != nrpr)
1695 (void)osd_jail_set_reserved(pr, sem_prison_slot, rsv,
1696 nrpr);
1697 else
1698 osd_free_reserved(rsv);
1699 prison_unlock(pr);
1700 if (orpr != nrpr) {
1701 if (orpr == pr)
1702 sem_prison_cleanup(pr);
1703 if (orpr != NULL) {
1704 /* Change child jails matching the old root, */
1705 FOREACH_PRISON_DESCENDANT(pr, tpr, descend) {
1706 prison_lock(tpr);
1707 trpr = osd_jail_get(tpr,
1708 sem_prison_slot);
1709 if (trpr == orpr) {
1710 (void)osd_jail_set(tpr,
1711 sem_prison_slot, nrpr);
1712 prison_unlock(tpr);
1713 if (trpr == tpr)
1714 sem_prison_cleanup(tpr);
1715 } else {
1716 prison_unlock(tpr);
1717 descend = 0;
1718 }
1719 }
1720 }
1721 }
1722 }
1723
1724 return (0);
1725 }
1726
1727 static int
sem_prison_get(void * obj,void * data)1728 sem_prison_get(void *obj, void *data)
1729 {
1730 struct prison *pr = obj;
1731 struct prison *rpr;
1732 struct vfsoptlist *opts = data;
1733 int error, jsys;
1734
1735 /* Set sysvsem based on the jail's root prison. */
1736 prison_lock(pr);
1737 rpr = osd_jail_get(pr, sem_prison_slot);
1738 prison_unlock(pr);
1739 jsys = rpr == NULL ? JAIL_SYS_DISABLE
1740 : rpr == pr ? JAIL_SYS_NEW : JAIL_SYS_INHERIT;
1741 error = vfs_setopt(opts, "sysvsem", &jsys, sizeof(jsys));
1742 if (error == ENOENT)
1743 error = 0;
1744 return (error);
1745 }
1746
1747 static int
sem_prison_remove(void * obj,void * data __unused)1748 sem_prison_remove(void *obj, void *data __unused)
1749 {
1750 struct prison *pr = obj;
1751 struct prison *rpr;
1752
1753 prison_lock(pr);
1754 rpr = osd_jail_get(pr, sem_prison_slot);
1755 prison_unlock(pr);
1756 if (rpr == pr)
1757 sem_prison_cleanup(pr);
1758 return (0);
1759 }
1760
1761 static void
sem_prison_cleanup(struct prison * pr)1762 sem_prison_cleanup(struct prison *pr)
1763 {
1764 int i;
1765
1766 /* Remove any sems that belong to this jail. */
1767 mtx_lock(&sem_mtx);
1768 for (i = 0; i < seminfo.semmni; i++) {
1769 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) &&
1770 sema[i].cred != NULL && sema[i].cred->cr_prison == pr) {
1771 mtx_lock(&sema_mtx[i]);
1772 sem_remove(i, NULL);
1773 mtx_unlock(&sema_mtx[i]);
1774 }
1775 }
1776 mtx_unlock(&sem_mtx);
1777 }
1778
1779 SYSCTL_JAIL_PARAM_SYS_NODE(sysvsem, CTLFLAG_RW, "SYSV semaphores");
1780
1781 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1782 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1783
1784 /* XXX casting to (sy_call_t *) is bogus, as usual. */
1785 static sy_call_t *semcalls[] = {
1786 (sy_call_t *)freebsd7___semctl, (sy_call_t *)sys_semget,
1787 (sy_call_t *)sys_semop
1788 };
1789
1790 /*
1791 * Entry point for all SEM calls.
1792 */
1793 int
sys_semsys(struct thread * td,struct semsys_args * uap)1794 sys_semsys(struct thread *td, struct semsys_args *uap)
1795 {
1796 int error;
1797
1798 AUDIT_ARG_SVIPC_WHICH(uap->which);
1799 if (uap->which < 0 || uap->which >= nitems(semcalls))
1800 return (EINVAL);
1801 error = (*semcalls[uap->which])(td, &uap->a2);
1802 return (error);
1803 }
1804
1805 #ifndef _SYS_SYSPROTO_H_
1806 struct freebsd7___semctl_args {
1807 int semid;
1808 int semnum;
1809 int cmd;
1810 union semun_old *arg;
1811 };
1812 #endif
1813 int
freebsd7___semctl(struct thread * td,struct freebsd7___semctl_args * uap)1814 freebsd7___semctl(struct thread *td, struct freebsd7___semctl_args *uap)
1815 {
1816 struct semid_ds_old dsold;
1817 struct semid_ds dsbuf;
1818 union semun_old arg;
1819 union semun semun;
1820 register_t rval;
1821 int error;
1822
1823 switch (uap->cmd) {
1824 case SEM_STAT:
1825 case IPC_SET:
1826 case IPC_STAT:
1827 case GETALL:
1828 case SETVAL:
1829 case SETALL:
1830 error = copyin(uap->arg, &arg, sizeof(arg));
1831 if (error)
1832 return (error);
1833 break;
1834 }
1835
1836 switch (uap->cmd) {
1837 case SEM_STAT:
1838 case IPC_STAT:
1839 semun.buf = &dsbuf;
1840 break;
1841 case IPC_SET:
1842 error = copyin(arg.buf, &dsold, sizeof(dsold));
1843 if (error)
1844 return (error);
1845 ipcperm_old2new(&dsold.sem_perm, &dsbuf.sem_perm);
1846 CP(dsold, dsbuf, __sem_base);
1847 CP(dsold, dsbuf, sem_nsems);
1848 CP(dsold, dsbuf, sem_otime);
1849 CP(dsold, dsbuf, sem_ctime);
1850 semun.buf = &dsbuf;
1851 break;
1852 case GETALL:
1853 case SETALL:
1854 semun.array = arg.array;
1855 break;
1856 case SETVAL:
1857 semun.val = arg.val;
1858 break;
1859 }
1860
1861 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun,
1862 &rval);
1863 if (error)
1864 return (error);
1865
1866 switch (uap->cmd) {
1867 case SEM_STAT:
1868 case IPC_STAT:
1869 bzero(&dsold, sizeof(dsold));
1870 ipcperm_new2old(&dsbuf.sem_perm, &dsold.sem_perm);
1871 CP(dsbuf, dsold, __sem_base);
1872 CP(dsbuf, dsold, sem_nsems);
1873 CP(dsbuf, dsold, sem_otime);
1874 CP(dsbuf, dsold, sem_ctime);
1875 error = copyout(&dsold, arg.buf, sizeof(dsold));
1876 break;
1877 }
1878
1879 if (error == 0)
1880 td->td_retval[0] = rval;
1881 return (error);
1882 }
1883
1884 #endif /* COMPAT_FREEBSD{4,5,6,7} */
1885
1886 #ifdef COMPAT_FREEBSD32
1887
1888 int
freebsd32_semsys(struct thread * td,struct freebsd32_semsys_args * uap)1889 freebsd32_semsys(struct thread *td, struct freebsd32_semsys_args *uap)
1890 {
1891
1892 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1893 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1894 AUDIT_ARG_SVIPC_WHICH(uap->which);
1895 switch (uap->which) {
1896 case 0:
1897 return (freebsd7_freebsd32___semctl(td,
1898 (struct freebsd7_freebsd32___semctl_args *)&uap->a2));
1899 default:
1900 return (sys_semsys(td, (struct semsys_args *)uap));
1901 }
1902 #else
1903 return (kern_nosys(td, 0));
1904 #endif
1905 }
1906
1907 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1908 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1909 int
freebsd7_freebsd32___semctl(struct thread * td,struct freebsd7_freebsd32___semctl_args * uap)1910 freebsd7_freebsd32___semctl(struct thread *td,
1911 struct freebsd7_freebsd32___semctl_args *uap)
1912 {
1913 struct semid_ds_old32 dsbuf32;
1914 struct semid_ds dsbuf;
1915 union semun semun;
1916 union semun_old32 arg;
1917 register_t rval;
1918 int error;
1919
1920 switch (uap->cmd) {
1921 case SEM_STAT:
1922 case IPC_SET:
1923 case IPC_STAT:
1924 case GETALL:
1925 case SETVAL:
1926 case SETALL:
1927 error = copyin(uap->arg, &arg, sizeof(arg));
1928 if (error)
1929 return (error);
1930 break;
1931 }
1932
1933 switch (uap->cmd) {
1934 case SEM_STAT:
1935 case IPC_STAT:
1936 semun.buf = &dsbuf;
1937 break;
1938 case IPC_SET:
1939 error = copyin(PTRIN(arg.buf), &dsbuf32, sizeof(dsbuf32));
1940 if (error)
1941 return (error);
1942 freebsd32_ipcperm_old_in(&dsbuf32.sem_perm, &dsbuf.sem_perm);
1943 PTRIN_CP(dsbuf32, dsbuf, __sem_base);
1944 CP(dsbuf32, dsbuf, sem_nsems);
1945 CP(dsbuf32, dsbuf, sem_otime);
1946 CP(dsbuf32, dsbuf, sem_ctime);
1947 semun.buf = &dsbuf;
1948 break;
1949 case GETALL:
1950 case SETALL:
1951 semun.array = PTRIN(arg.array);
1952 break;
1953 case SETVAL:
1954 semun.val = arg.val;
1955 break;
1956 }
1957
1958 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun,
1959 &rval);
1960 if (error)
1961 return (error);
1962
1963 switch (uap->cmd) {
1964 case SEM_STAT:
1965 case IPC_STAT:
1966 bzero(&dsbuf32, sizeof(dsbuf32));
1967 freebsd32_ipcperm_old_out(&dsbuf.sem_perm, &dsbuf32.sem_perm);
1968 PTROUT_CP(dsbuf, dsbuf32, __sem_base);
1969 CP(dsbuf, dsbuf32, sem_nsems);
1970 CP(dsbuf, dsbuf32, sem_otime);
1971 CP(dsbuf, dsbuf32, sem_ctime);
1972 error = copyout(&dsbuf32, PTRIN(arg.buf), sizeof(dsbuf32));
1973 break;
1974 }
1975
1976 if (error == 0)
1977 td->td_retval[0] = rval;
1978 return (error);
1979 }
1980 #endif
1981
1982 int
freebsd32___semctl(struct thread * td,struct freebsd32___semctl_args * uap)1983 freebsd32___semctl(struct thread *td, struct freebsd32___semctl_args *uap)
1984 {
1985 struct semid_ds32 dsbuf32;
1986 struct semid_ds dsbuf;
1987 union semun semun;
1988 union semun32 arg;
1989 register_t rval;
1990 int error;
1991
1992 switch (uap->cmd) {
1993 case SEM_STAT:
1994 case IPC_SET:
1995 case IPC_STAT:
1996 case GETALL:
1997 case SETVAL:
1998 case SETALL:
1999 error = copyin(uap->arg, &arg, sizeof(arg));
2000 if (error)
2001 return (error);
2002 break;
2003 }
2004
2005 switch (uap->cmd) {
2006 case SEM_STAT:
2007 case IPC_STAT:
2008 semun.buf = &dsbuf;
2009 break;
2010 case IPC_SET:
2011 error = copyin(PTRIN(arg.buf), &dsbuf32, sizeof(dsbuf32));
2012 if (error)
2013 return (error);
2014 freebsd32_ipcperm_in(&dsbuf32.sem_perm, &dsbuf.sem_perm);
2015 PTRIN_CP(dsbuf32, dsbuf, __sem_base);
2016 CP(dsbuf32, dsbuf, sem_nsems);
2017 CP(dsbuf32, dsbuf, sem_otime);
2018 CP(dsbuf32, dsbuf, sem_ctime);
2019 semun.buf = &dsbuf;
2020 break;
2021 case GETALL:
2022 case SETALL:
2023 semun.array = PTRIN(arg.array);
2024 break;
2025 case SETVAL:
2026 semun.val = arg.val;
2027 break;
2028 }
2029
2030 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun,
2031 &rval);
2032 if (error)
2033 return (error);
2034
2035 switch (uap->cmd) {
2036 case SEM_STAT:
2037 case IPC_STAT:
2038 bzero(&dsbuf32, sizeof(dsbuf32));
2039 freebsd32_ipcperm_out(&dsbuf.sem_perm, &dsbuf32.sem_perm);
2040 PTROUT_CP(dsbuf, dsbuf32, __sem_base);
2041 CP(dsbuf, dsbuf32, sem_nsems);
2042 CP(dsbuf, dsbuf32, sem_otime);
2043 CP(dsbuf, dsbuf32, sem_ctime);
2044 error = copyout(&dsbuf32, PTRIN(arg.buf), sizeof(dsbuf32));
2045 break;
2046 }
2047
2048 if (error == 0)
2049 td->td_retval[0] = rval;
2050 return (error);
2051 }
2052
2053 #endif /* COMPAT_FREEBSD32 */
2054