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-FreeBSD 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 <sys/cdefs.h> 48 __FBSDID("$FreeBSD$"); 49 50 #include "opt_sysvipc.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/sysproto.h> 55 #include <sys/abi_compat.h> 56 #include <sys/eventhandler.h> 57 #include <sys/kernel.h> 58 #include <sys/proc.h> 59 #include <sys/lock.h> 60 #include <sys/module.h> 61 #include <sys/mutex.h> 62 #include <sys/racct.h> 63 #include <sys/sem.h> 64 #include <sys/sx.h> 65 #include <sys/syscall.h> 66 #include <sys/syscallsubr.h> 67 #include <sys/sysent.h> 68 #include <sys/sysctl.h> 69 #include <sys/uio.h> 70 #include <sys/malloc.h> 71 #include <sys/jail.h> 72 73 #include <security/audit/audit.h> 74 #include <security/mac/mac_framework.h> 75 76 FEATURE(sysv_sem, "System V semaphores support"); 77 78 static MALLOC_DEFINE(M_SEM, "sem", "SVID compatible semaphores"); 79 80 #ifdef SEM_DEBUG 81 #define DPRINTF(a) printf a 82 #else 83 #define DPRINTF(a) 84 #endif 85 86 static int seminit(void); 87 static int sysvsem_modload(struct module *, int, void *); 88 static int semunload(void); 89 static void semexit_myhook(void *arg, struct proc *p); 90 static int sysctl_sema(SYSCTL_HANDLER_ARGS); 91 static int semvalid(int semid, struct prison *rpr, 92 struct semid_kernel *semakptr); 93 static void sem_remove(int semidx, struct ucred *cred); 94 static struct prison *sem_find_prison(struct ucred *); 95 static int sem_prison_cansee(struct prison *, struct semid_kernel *); 96 static int sem_prison_check(void *, void *); 97 static int sem_prison_set(void *, void *); 98 static int sem_prison_get(void *, void *); 99 static int sem_prison_remove(void *, void *); 100 static void sem_prison_cleanup(struct prison *); 101 102 #ifndef _SYS_SYSPROTO_H_ 103 struct __semctl_args; 104 int __semctl(struct thread *td, struct __semctl_args *uap); 105 struct semget_args; 106 int semget(struct thread *td, struct semget_args *uap); 107 struct semop_args; 108 int semop(struct thread *td, struct semop_args *uap); 109 #endif 110 111 static struct sem_undo *semu_alloc(struct thread *td); 112 static int semundo_adjust(struct thread *td, struct sem_undo **supptr, 113 int semid, int semseq, int semnum, int adjval); 114 static void semundo_clear(int semid, int semnum); 115 116 static struct mtx sem_mtx; /* semaphore global lock */ 117 static struct mtx sem_undo_mtx; 118 static int semtot = 0; 119 static struct semid_kernel *sema; /* semaphore id pool */ 120 static struct mtx *sema_mtx; /* semaphore id pool mutexes*/ 121 static struct sem *sem; /* semaphore pool */ 122 LIST_HEAD(, sem_undo) semu_list; /* list of active undo structures */ 123 LIST_HEAD(, sem_undo) semu_free_list; /* list of free undo structures */ 124 static int *semu; /* undo structure pool */ 125 static eventhandler_tag semexit_tag; 126 static unsigned sem_prison_slot; /* prison OSD slot */ 127 128 #define SEMUNDO_MTX sem_undo_mtx 129 #define SEMUNDO_LOCK() mtx_lock(&SEMUNDO_MTX); 130 #define SEMUNDO_UNLOCK() mtx_unlock(&SEMUNDO_MTX); 131 #define SEMUNDO_LOCKASSERT(how) mtx_assert(&SEMUNDO_MTX, (how)); 132 133 struct sem { 134 u_short semval; /* semaphore value */ 135 pid_t sempid; /* pid of last operation */ 136 u_short semncnt; /* # awaiting semval > cval */ 137 u_short semzcnt; /* # awaiting semval = 0 */ 138 }; 139 140 /* 141 * Undo structure (one per process) 142 */ 143 struct sem_undo { 144 LIST_ENTRY(sem_undo) un_next; /* ptr to next active undo structure */ 145 struct proc *un_proc; /* owner of this structure */ 146 short un_cnt; /* # of active entries */ 147 struct undo { 148 short un_adjval; /* adjust on exit values */ 149 short un_num; /* semaphore # */ 150 int un_id; /* semid */ 151 unsigned short un_seq; 152 } un_ent[1]; /* undo entries */ 153 }; 154 155 /* 156 * Configuration parameters 157 */ 158 #ifndef SEMMNI 159 #define SEMMNI 50 /* # of semaphore identifiers */ 160 #endif 161 #ifndef SEMMNS 162 #define SEMMNS 340 /* # of semaphores in system */ 163 #endif 164 #ifndef SEMUME 165 #define SEMUME 50 /* max # of undo entries per process */ 166 #endif 167 #ifndef SEMMNU 168 #define SEMMNU 150 /* # of undo structures in system */ 169 #endif 170 171 /* shouldn't need tuning */ 172 #ifndef SEMMSL 173 #define SEMMSL SEMMNS /* max # of semaphores per id */ 174 #endif 175 #ifndef SEMOPM 176 #define SEMOPM 100 /* max # of operations per semop call */ 177 #endif 178 179 #define SEMVMX 32767 /* semaphore maximum value */ 180 #define SEMAEM 16384 /* adjust on exit max value */ 181 182 /* 183 * Due to the way semaphore memory is allocated, we have to ensure that 184 * SEMUSZ is properly aligned. 185 */ 186 187 #define SEM_ALIGN(bytes) roundup2(bytes, sizeof(long)) 188 189 /* actual size of an undo structure */ 190 #define SEMUSZ(x) SEM_ALIGN(offsetof(struct sem_undo, un_ent[(x)])) 191 192 /* 193 * Macro to find a particular sem_undo vector 194 */ 195 #define SEMU(ix) \ 196 ((struct sem_undo *)(((intptr_t)semu) + (ix) * seminfo.semusz)) 197 198 /* 199 * semaphore info struct 200 */ 201 struct seminfo seminfo = { 202 .semmni = SEMMNI, /* # of semaphore identifiers */ 203 .semmns = SEMMNS, /* # of semaphores in system */ 204 .semmnu = SEMMNU, /* # of undo structures in system */ 205 .semmsl = SEMMSL, /* max # of semaphores per id */ 206 .semopm = SEMOPM, /* max # of operations per semop call */ 207 .semume = SEMUME, /* max # of undo entries per process */ 208 .semusz = SEMUSZ(SEMUME), /* size in bytes of undo structure */ 209 .semvmx = SEMVMX, /* semaphore maximum value */ 210 .semaem = SEMAEM, /* adjust on exit max value */ 211 }; 212 213 SYSCTL_INT(_kern_ipc, OID_AUTO, semmni, CTLFLAG_RDTUN, &seminfo.semmni, 0, 214 "Number of semaphore identifiers"); 215 SYSCTL_INT(_kern_ipc, OID_AUTO, semmns, CTLFLAG_RDTUN, &seminfo.semmns, 0, 216 "Maximum number of semaphores in the system"); 217 SYSCTL_INT(_kern_ipc, OID_AUTO, semmnu, CTLFLAG_RDTUN, &seminfo.semmnu, 0, 218 "Maximum number of undo structures in the system"); 219 SYSCTL_INT(_kern_ipc, OID_AUTO, semmsl, CTLFLAG_RWTUN, &seminfo.semmsl, 0, 220 "Max semaphores per id"); 221 SYSCTL_INT(_kern_ipc, OID_AUTO, semopm, CTLFLAG_RDTUN, &seminfo.semopm, 0, 222 "Max operations per semop call"); 223 SYSCTL_INT(_kern_ipc, OID_AUTO, semume, CTLFLAG_RDTUN, &seminfo.semume, 0, 224 "Max undo entries per process"); 225 SYSCTL_INT(_kern_ipc, OID_AUTO, semusz, CTLFLAG_RD, &seminfo.semusz, 0, 226 "Size in bytes of undo structure"); 227 SYSCTL_INT(_kern_ipc, OID_AUTO, semvmx, CTLFLAG_RWTUN, &seminfo.semvmx, 0, 228 "Semaphore maximum value"); 229 SYSCTL_INT(_kern_ipc, OID_AUTO, semaem, CTLFLAG_RWTUN, &seminfo.semaem, 0, 230 "Adjust on exit max value"); 231 SYSCTL_PROC(_kern_ipc, OID_AUTO, sema, 232 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, 233 NULL, 0, sysctl_sema, "", 234 "Array of struct semid_kernel for each potential semaphore"); 235 236 static struct syscall_helper_data sem_syscalls[] = { 237 SYSCALL_INIT_HELPER(__semctl), 238 SYSCALL_INIT_HELPER(semget), 239 SYSCALL_INIT_HELPER(semop), 240 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \ 241 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7) 242 SYSCALL_INIT_HELPER(semsys), 243 SYSCALL_INIT_HELPER_COMPAT(freebsd7___semctl), 244 #endif 245 SYSCALL_INIT_LAST 246 }; 247 248 #ifdef COMPAT_FREEBSD32 249 #include <compat/freebsd32/freebsd32.h> 250 #include <compat/freebsd32/freebsd32_ipc.h> 251 #include <compat/freebsd32/freebsd32_proto.h> 252 #include <compat/freebsd32/freebsd32_signal.h> 253 #include <compat/freebsd32/freebsd32_syscall.h> 254 #include <compat/freebsd32/freebsd32_util.h> 255 256 static struct syscall_helper_data sem32_syscalls[] = { 257 SYSCALL32_INIT_HELPER(freebsd32___semctl), 258 SYSCALL32_INIT_HELPER_COMPAT(semget), 259 SYSCALL32_INIT_HELPER_COMPAT(semop), 260 SYSCALL32_INIT_HELPER(freebsd32_semsys), 261 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \ 262 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7) 263 SYSCALL32_INIT_HELPER(freebsd7_freebsd32___semctl), 264 #endif 265 SYSCALL_INIT_LAST 266 }; 267 #endif 268 269 static int 270 seminit(void) 271 { 272 struct prison *pr; 273 void **rsv; 274 int i, error; 275 osd_method_t methods[PR_MAXMETHOD] = { 276 [PR_METHOD_CHECK] = sem_prison_check, 277 [PR_METHOD_SET] = sem_prison_set, 278 [PR_METHOD_GET] = sem_prison_get, 279 [PR_METHOD_REMOVE] = sem_prison_remove, 280 }; 281 282 sem = malloc(sizeof(struct sem) * seminfo.semmns, M_SEM, M_WAITOK); 283 sema = malloc(sizeof(struct semid_kernel) * seminfo.semmni, M_SEM, 284 M_WAITOK | M_ZERO); 285 sema_mtx = malloc(sizeof(struct mtx) * seminfo.semmni, M_SEM, 286 M_WAITOK | M_ZERO); 287 seminfo.semusz = SEMUSZ(seminfo.semume); 288 semu = malloc(seminfo.semmnu * seminfo.semusz, M_SEM, M_WAITOK); 289 290 for (i = 0; i < seminfo.semmni; i++) { 291 sema[i].u.__sem_base = 0; 292 sema[i].u.sem_perm.mode = 0; 293 sema[i].u.sem_perm.seq = 0; 294 #ifdef MAC 295 mac_sysvsem_init(&sema[i]); 296 #endif 297 } 298 for (i = 0; i < seminfo.semmni; i++) 299 mtx_init(&sema_mtx[i], "semid", NULL, MTX_DEF); 300 LIST_INIT(&semu_free_list); 301 for (i = 0; i < seminfo.semmnu; i++) { 302 struct sem_undo *suptr = SEMU(i); 303 suptr->un_proc = NULL; 304 LIST_INSERT_HEAD(&semu_free_list, suptr, un_next); 305 } 306 LIST_INIT(&semu_list); 307 mtx_init(&sem_mtx, "sem", NULL, MTX_DEF); 308 mtx_init(&sem_undo_mtx, "semu", NULL, MTX_DEF); 309 semexit_tag = EVENTHANDLER_REGISTER(process_exit, semexit_myhook, NULL, 310 EVENTHANDLER_PRI_ANY); 311 312 /* Set current prisons according to their allow.sysvipc. */ 313 sem_prison_slot = osd_jail_register(NULL, methods); 314 rsv = osd_reserve(sem_prison_slot); 315 prison_lock(&prison0); 316 (void)osd_jail_set_reserved(&prison0, sem_prison_slot, rsv, &prison0); 317 prison_unlock(&prison0); 318 rsv = NULL; 319 sx_slock(&allprison_lock); 320 TAILQ_FOREACH(pr, &allprison, pr_list) { 321 if (rsv == NULL) 322 rsv = osd_reserve(sem_prison_slot); 323 prison_lock(pr); 324 if (pr->pr_allow & PR_ALLOW_SYSVIPC) { 325 (void)osd_jail_set_reserved(pr, sem_prison_slot, rsv, 326 &prison0); 327 rsv = NULL; 328 } 329 prison_unlock(pr); 330 } 331 if (rsv != NULL) 332 osd_free_reserved(rsv); 333 sx_sunlock(&allprison_lock); 334 335 error = syscall_helper_register(sem_syscalls, SY_THR_STATIC_KLD); 336 if (error != 0) 337 return (error); 338 #ifdef COMPAT_FREEBSD32 339 error = syscall32_helper_register(sem32_syscalls, SY_THR_STATIC_KLD); 340 if (error != 0) 341 return (error); 342 #endif 343 return (0); 344 } 345 346 static int 347 semunload(void) 348 { 349 int i; 350 351 /* XXXKIB */ 352 if (semtot != 0) 353 return (EBUSY); 354 355 #ifdef COMPAT_FREEBSD32 356 syscall32_helper_unregister(sem32_syscalls); 357 #endif 358 syscall_helper_unregister(sem_syscalls); 359 EVENTHANDLER_DEREGISTER(process_exit, semexit_tag); 360 if (sem_prison_slot != 0) 361 osd_jail_deregister(sem_prison_slot); 362 #ifdef MAC 363 for (i = 0; i < seminfo.semmni; i++) 364 mac_sysvsem_destroy(&sema[i]); 365 #endif 366 free(sem, M_SEM); 367 free(sema, M_SEM); 368 free(semu, M_SEM); 369 for (i = 0; i < seminfo.semmni; i++) 370 mtx_destroy(&sema_mtx[i]); 371 free(sema_mtx, M_SEM); 372 mtx_destroy(&sem_mtx); 373 mtx_destroy(&sem_undo_mtx); 374 return (0); 375 } 376 377 static int 378 sysvsem_modload(struct module *module, int cmd, void *arg) 379 { 380 int error = 0; 381 382 switch (cmd) { 383 case MOD_LOAD: 384 error = seminit(); 385 break; 386 case MOD_UNLOAD: 387 error = semunload(); 388 break; 389 case MOD_SHUTDOWN: 390 break; 391 default: 392 error = EINVAL; 393 break; 394 } 395 return (error); 396 } 397 398 static moduledata_t sysvsem_mod = { 399 "sysvsem", 400 &sysvsem_modload, 401 NULL 402 }; 403 404 DECLARE_MODULE(sysvsem, sysvsem_mod, SI_SUB_SYSV_SEM, SI_ORDER_FIRST); 405 MODULE_VERSION(sysvsem, 1); 406 407 /* 408 * Allocate a new sem_undo structure for a process 409 * (returns ptr to structure or NULL if no more room) 410 */ 411 412 static struct sem_undo * 413 semu_alloc(struct thread *td) 414 { 415 struct sem_undo *suptr; 416 417 SEMUNDO_LOCKASSERT(MA_OWNED); 418 if ((suptr = LIST_FIRST(&semu_free_list)) == NULL) 419 return (NULL); 420 LIST_REMOVE(suptr, un_next); 421 LIST_INSERT_HEAD(&semu_list, suptr, un_next); 422 suptr->un_cnt = 0; 423 suptr->un_proc = td->td_proc; 424 return (suptr); 425 } 426 427 static int 428 semu_try_free(struct sem_undo *suptr) 429 { 430 431 SEMUNDO_LOCKASSERT(MA_OWNED); 432 433 if (suptr->un_cnt != 0) 434 return (0); 435 LIST_REMOVE(suptr, un_next); 436 LIST_INSERT_HEAD(&semu_free_list, suptr, un_next); 437 return (1); 438 } 439 440 /* 441 * Adjust a particular entry for a particular proc 442 */ 443 444 static int 445 semundo_adjust(struct thread *td, struct sem_undo **supptr, int semid, 446 int semseq, int semnum, int adjval) 447 { 448 struct proc *p = td->td_proc; 449 struct sem_undo *suptr; 450 struct undo *sunptr; 451 int i; 452 453 SEMUNDO_LOCKASSERT(MA_OWNED); 454 /* Look for and remember the sem_undo if the caller doesn't provide 455 it */ 456 457 suptr = *supptr; 458 if (suptr == NULL) { 459 LIST_FOREACH(suptr, &semu_list, un_next) { 460 if (suptr->un_proc == p) { 461 *supptr = suptr; 462 break; 463 } 464 } 465 if (suptr == NULL) { 466 if (adjval == 0) 467 return(0); 468 suptr = semu_alloc(td); 469 if (suptr == NULL) 470 return (ENOSPC); 471 *supptr = suptr; 472 } 473 } 474 475 /* 476 * Look for the requested entry and adjust it (delete if adjval becomes 477 * 0). 478 */ 479 sunptr = &suptr->un_ent[0]; 480 for (i = 0; i < suptr->un_cnt; i++, sunptr++) { 481 if (sunptr->un_id != semid || sunptr->un_num != semnum) 482 continue; 483 if (adjval != 0) { 484 adjval += sunptr->un_adjval; 485 if (adjval > seminfo.semaem || adjval < -seminfo.semaem) 486 return (ERANGE); 487 } 488 sunptr->un_adjval = adjval; 489 if (sunptr->un_adjval == 0) { 490 suptr->un_cnt--; 491 if (i < suptr->un_cnt) 492 suptr->un_ent[i] = 493 suptr->un_ent[suptr->un_cnt]; 494 if (suptr->un_cnt == 0) 495 semu_try_free(suptr); 496 } 497 return (0); 498 } 499 500 /* Didn't find the right entry - create it */ 501 if (adjval == 0) 502 return (0); 503 if (adjval > seminfo.semaem || adjval < -seminfo.semaem) 504 return (ERANGE); 505 if (suptr->un_cnt != seminfo.semume) { 506 sunptr = &suptr->un_ent[suptr->un_cnt]; 507 suptr->un_cnt++; 508 sunptr->un_adjval = adjval; 509 sunptr->un_id = semid; 510 sunptr->un_num = semnum; 511 sunptr->un_seq = semseq; 512 } else 513 return (EINVAL); 514 return (0); 515 } 516 517 static void 518 semundo_clear(int semid, int semnum) 519 { 520 struct sem_undo *suptr, *suptr1; 521 struct undo *sunptr; 522 int i; 523 524 SEMUNDO_LOCKASSERT(MA_OWNED); 525 LIST_FOREACH_SAFE(suptr, &semu_list, un_next, suptr1) { 526 sunptr = &suptr->un_ent[0]; 527 for (i = 0; i < suptr->un_cnt; i++, sunptr++) { 528 if (sunptr->un_id != semid) 529 continue; 530 if (semnum == -1 || sunptr->un_num == semnum) { 531 suptr->un_cnt--; 532 if (i < suptr->un_cnt) { 533 suptr->un_ent[i] = 534 suptr->un_ent[suptr->un_cnt]; 535 continue; 536 } 537 semu_try_free(suptr); 538 } 539 if (semnum != -1) 540 break; 541 } 542 } 543 } 544 545 static int 546 semvalid(int semid, struct prison *rpr, struct semid_kernel *semakptr) 547 { 548 549 return ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 || 550 semakptr->u.sem_perm.seq != IPCID_TO_SEQ(semid) || 551 sem_prison_cansee(rpr, semakptr) ? EINVAL : 0); 552 } 553 554 static void 555 sem_remove(int semidx, struct ucred *cred) 556 { 557 struct semid_kernel *semakptr; 558 int i; 559 560 KASSERT(semidx >= 0 && semidx < seminfo.semmni, 561 ("semidx out of bounds")); 562 mtx_assert(&sem_mtx, MA_OWNED); 563 semakptr = &sema[semidx]; 564 KASSERT(semakptr->u.__sem_base - sem + semakptr->u.sem_nsems <= semtot, 565 ("sem_remove: sema %d corrupted sem pointer %p %p %d %d", 566 semidx, semakptr->u.__sem_base, sem, semakptr->u.sem_nsems, 567 semtot)); 568 569 semakptr->u.sem_perm.cuid = cred ? cred->cr_uid : 0; 570 semakptr->u.sem_perm.uid = cred ? cred->cr_uid : 0; 571 semakptr->u.sem_perm.mode = 0; 572 racct_sub_cred(semakptr->cred, RACCT_NSEM, semakptr->u.sem_nsems); 573 crfree(semakptr->cred); 574 semakptr->cred = NULL; 575 SEMUNDO_LOCK(); 576 semundo_clear(semidx, -1); 577 SEMUNDO_UNLOCK(); 578 #ifdef MAC 579 mac_sysvsem_cleanup(semakptr); 580 #endif 581 wakeup(semakptr); 582 for (i = 0; i < seminfo.semmni; i++) { 583 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) && 584 sema[i].u.__sem_base > semakptr->u.__sem_base) 585 mtx_lock_flags(&sema_mtx[i], LOP_DUPOK); 586 } 587 for (i = semakptr->u.__sem_base - sem + semakptr->u.sem_nsems; 588 i < semtot; i++) 589 sem[i - semakptr->u.sem_nsems] = sem[i]; 590 for (i = 0; i < seminfo.semmni; i++) { 591 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) && 592 sema[i].u.__sem_base > semakptr->u.__sem_base) { 593 sema[i].u.__sem_base -= semakptr->u.sem_nsems; 594 mtx_unlock(&sema_mtx[i]); 595 } 596 } 597 semtot -= semakptr->u.sem_nsems; 598 } 599 600 static struct prison * 601 sem_find_prison(struct ucred *cred) 602 { 603 struct prison *pr, *rpr; 604 605 pr = cred->cr_prison; 606 prison_lock(pr); 607 rpr = osd_jail_get(pr, sem_prison_slot); 608 prison_unlock(pr); 609 return rpr; 610 } 611 612 static int 613 sem_prison_cansee(struct prison *rpr, struct semid_kernel *semakptr) 614 { 615 616 if (semakptr->cred == NULL || 617 !(rpr == semakptr->cred->cr_prison || 618 prison_ischild(rpr, semakptr->cred->cr_prison))) 619 return (EINVAL); 620 return (0); 621 } 622 623 /* 624 * Note that the user-mode half of this passes a union, not a pointer. 625 */ 626 #ifndef _SYS_SYSPROTO_H_ 627 struct __semctl_args { 628 int semid; 629 int semnum; 630 int cmd; 631 union semun *arg; 632 }; 633 #endif 634 int 635 sys___semctl(struct thread *td, struct __semctl_args *uap) 636 { 637 struct semid_ds dsbuf; 638 union semun arg, semun; 639 register_t rval; 640 int error; 641 642 switch (uap->cmd) { 643 case SEM_STAT: 644 case IPC_SET: 645 case IPC_STAT: 646 case GETALL: 647 case SETVAL: 648 case SETALL: 649 error = copyin(uap->arg, &arg, sizeof(arg)); 650 if (error) 651 return (error); 652 break; 653 } 654 655 switch (uap->cmd) { 656 case SEM_STAT: 657 case IPC_STAT: 658 semun.buf = &dsbuf; 659 break; 660 case IPC_SET: 661 error = copyin(arg.buf, &dsbuf, sizeof(dsbuf)); 662 if (error) 663 return (error); 664 semun.buf = &dsbuf; 665 break; 666 case GETALL: 667 case SETALL: 668 semun.array = arg.array; 669 break; 670 case SETVAL: 671 semun.val = arg.val; 672 break; 673 } 674 675 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun, 676 &rval); 677 if (error) 678 return (error); 679 680 switch (uap->cmd) { 681 case SEM_STAT: 682 case IPC_STAT: 683 error = copyout(&dsbuf, arg.buf, sizeof(dsbuf)); 684 break; 685 } 686 687 if (error == 0) 688 td->td_retval[0] = rval; 689 return (error); 690 } 691 692 int 693 kern_semctl(struct thread *td, int semid, int semnum, int cmd, 694 union semun *arg, register_t *rval) 695 { 696 u_short *array; 697 struct ucred *cred = td->td_ucred; 698 int i, error; 699 struct prison *rpr; 700 struct semid_ds *sbuf; 701 struct semid_kernel *semakptr; 702 struct mtx *sema_mtxp; 703 u_short usval, count; 704 int semidx; 705 706 DPRINTF(("call to semctl(%d, %d, %d, 0x%p)\n", 707 semid, semnum, cmd, arg)); 708 709 AUDIT_ARG_SVIPC_CMD(cmd); 710 AUDIT_ARG_SVIPC_ID(semid); 711 712 rpr = sem_find_prison(td->td_ucred); 713 if (sem == NULL) 714 return (ENOSYS); 715 716 array = NULL; 717 718 switch(cmd) { 719 case SEM_STAT: 720 /* 721 * For this command we assume semid is an array index 722 * rather than an IPC id. 723 */ 724 if (semid < 0 || semid >= seminfo.semmni) 725 return (EINVAL); 726 semakptr = &sema[semid]; 727 sema_mtxp = &sema_mtx[semid]; 728 mtx_lock(sema_mtxp); 729 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0) { 730 error = EINVAL; 731 goto done2; 732 } 733 if ((error = sem_prison_cansee(rpr, semakptr))) 734 goto done2; 735 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R))) 736 goto done2; 737 #ifdef MAC 738 error = mac_sysvsem_check_semctl(cred, semakptr, cmd); 739 if (error != 0) 740 goto done2; 741 #endif 742 bcopy(&semakptr->u, arg->buf, sizeof(struct semid_ds)); 743 if (cred->cr_prison != semakptr->cred->cr_prison) 744 arg->buf->sem_perm.key = IPC_PRIVATE; 745 *rval = IXSEQ_TO_IPCID(semid, semakptr->u.sem_perm); 746 mtx_unlock(sema_mtxp); 747 return (0); 748 } 749 750 semidx = IPCID_TO_IX(semid); 751 if (semidx < 0 || semidx >= seminfo.semmni) 752 return (EINVAL); 753 754 semakptr = &sema[semidx]; 755 sema_mtxp = &sema_mtx[semidx]; 756 if (cmd == IPC_RMID) 757 mtx_lock(&sem_mtx); 758 mtx_lock(sema_mtxp); 759 760 #ifdef MAC 761 error = mac_sysvsem_check_semctl(cred, semakptr, cmd); 762 if (error != 0) 763 goto done2; 764 #endif 765 766 error = 0; 767 *rval = 0; 768 769 switch (cmd) { 770 case IPC_RMID: 771 if ((error = semvalid(semid, rpr, semakptr)) != 0) 772 goto done2; 773 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_M))) 774 goto done2; 775 sem_remove(semidx, cred); 776 break; 777 778 case IPC_SET: 779 AUDIT_ARG_SVIPC_PERM(&arg->buf->sem_perm); 780 if ((error = semvalid(semid, rpr, semakptr)) != 0) 781 goto done2; 782 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_M))) 783 goto done2; 784 sbuf = arg->buf; 785 semakptr->u.sem_perm.uid = sbuf->sem_perm.uid; 786 semakptr->u.sem_perm.gid = sbuf->sem_perm.gid; 787 semakptr->u.sem_perm.mode = (semakptr->u.sem_perm.mode & 788 ~0777) | (sbuf->sem_perm.mode & 0777); 789 semakptr->u.sem_ctime = time_second; 790 break; 791 792 case IPC_STAT: 793 if ((error = semvalid(semid, rpr, semakptr)) != 0) 794 goto done2; 795 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R))) 796 goto done2; 797 bcopy(&semakptr->u, arg->buf, sizeof(struct semid_ds)); 798 if (cred->cr_prison != semakptr->cred->cr_prison) 799 arg->buf->sem_perm.key = IPC_PRIVATE; 800 801 /* 802 * Try to hide the fact that the structure layout is shared by 803 * both the kernel and userland. This pointer is not useful to 804 * userspace. 805 */ 806 arg->buf->__sem_base = NULL; 807 break; 808 809 case GETNCNT: 810 if ((error = semvalid(semid, rpr, semakptr)) != 0) 811 goto done2; 812 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R))) 813 goto done2; 814 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) { 815 error = EINVAL; 816 goto done2; 817 } 818 *rval = semakptr->u.__sem_base[semnum].semncnt; 819 break; 820 821 case GETPID: 822 if ((error = semvalid(semid, rpr, semakptr)) != 0) 823 goto done2; 824 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R))) 825 goto done2; 826 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) { 827 error = EINVAL; 828 goto done2; 829 } 830 *rval = semakptr->u.__sem_base[semnum].sempid; 831 break; 832 833 case GETVAL: 834 if ((error = semvalid(semid, rpr, semakptr)) != 0) 835 goto done2; 836 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R))) 837 goto done2; 838 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) { 839 error = EINVAL; 840 goto done2; 841 } 842 *rval = semakptr->u.__sem_base[semnum].semval; 843 break; 844 845 case GETALL: 846 /* 847 * Unfortunately, callers of this function don't know 848 * in advance how many semaphores are in this set. 849 * While we could just allocate the maximum size array 850 * and pass the actual size back to the caller, that 851 * won't work for SETALL since we can't copyin() more 852 * data than the user specified as we may return a 853 * spurious EFAULT. 854 * 855 * Note that the number of semaphores in a set is 856 * fixed for the life of that set. The only way that 857 * the 'count' could change while are blocked in 858 * malloc() is if this semaphore set were destroyed 859 * and a new one created with the same index. 860 * However, semvalid() will catch that due to the 861 * sequence number unless exactly 0x8000 (or a 862 * multiple thereof) semaphore sets for the same index 863 * are created and destroyed while we are in malloc! 864 * 865 */ 866 count = semakptr->u.sem_nsems; 867 mtx_unlock(sema_mtxp); 868 array = malloc(sizeof(*array) * count, M_TEMP, M_WAITOK); 869 mtx_lock(sema_mtxp); 870 if ((error = semvalid(semid, rpr, semakptr)) != 0) 871 goto done2; 872 KASSERT(count == semakptr->u.sem_nsems, ("nsems changed")); 873 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R))) 874 goto done2; 875 for (i = 0; i < semakptr->u.sem_nsems; i++) 876 array[i] = semakptr->u.__sem_base[i].semval; 877 mtx_unlock(sema_mtxp); 878 error = copyout(array, arg->array, count * sizeof(*array)); 879 mtx_lock(sema_mtxp); 880 break; 881 882 case GETZCNT: 883 if ((error = semvalid(semid, rpr, semakptr)) != 0) 884 goto done2; 885 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_R))) 886 goto done2; 887 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) { 888 error = EINVAL; 889 goto done2; 890 } 891 *rval = semakptr->u.__sem_base[semnum].semzcnt; 892 break; 893 894 case SETVAL: 895 if ((error = semvalid(semid, rpr, semakptr)) != 0) 896 goto done2; 897 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_W))) 898 goto done2; 899 if (semnum < 0 || semnum >= semakptr->u.sem_nsems) { 900 error = EINVAL; 901 goto done2; 902 } 903 if (arg->val < 0 || arg->val > seminfo.semvmx) { 904 error = ERANGE; 905 goto done2; 906 } 907 semakptr->u.__sem_base[semnum].semval = arg->val; 908 SEMUNDO_LOCK(); 909 semundo_clear(semidx, semnum); 910 SEMUNDO_UNLOCK(); 911 wakeup(semakptr); 912 break; 913 914 case SETALL: 915 /* 916 * See comment on GETALL for why 'count' shouldn't change 917 * and why we require a userland buffer. 918 */ 919 count = semakptr->u.sem_nsems; 920 mtx_unlock(sema_mtxp); 921 array = malloc(sizeof(*array) * count, M_TEMP, M_WAITOK); 922 error = copyin(arg->array, array, count * sizeof(*array)); 923 mtx_lock(sema_mtxp); 924 if (error) 925 break; 926 if ((error = semvalid(semid, rpr, semakptr)) != 0) 927 goto done2; 928 KASSERT(count == semakptr->u.sem_nsems, ("nsems changed")); 929 if ((error = ipcperm(td, &semakptr->u.sem_perm, IPC_W))) 930 goto done2; 931 for (i = 0; i < semakptr->u.sem_nsems; i++) { 932 usval = array[i]; 933 if (usval > seminfo.semvmx) { 934 error = ERANGE; 935 break; 936 } 937 semakptr->u.__sem_base[i].semval = usval; 938 } 939 SEMUNDO_LOCK(); 940 semundo_clear(semidx, -1); 941 SEMUNDO_UNLOCK(); 942 wakeup(semakptr); 943 break; 944 945 default: 946 error = EINVAL; 947 break; 948 } 949 950 done2: 951 mtx_unlock(sema_mtxp); 952 if (cmd == IPC_RMID) 953 mtx_unlock(&sem_mtx); 954 if (array != NULL) 955 free(array, M_TEMP); 956 return(error); 957 } 958 959 #ifndef _SYS_SYSPROTO_H_ 960 struct semget_args { 961 key_t key; 962 int nsems; 963 int semflg; 964 }; 965 #endif 966 int 967 sys_semget(struct thread *td, struct semget_args *uap) 968 { 969 int semid, error = 0; 970 int key = uap->key; 971 int nsems = uap->nsems; 972 int semflg = uap->semflg; 973 struct ucred *cred = td->td_ucred; 974 975 DPRINTF(("semget(0x%x, %d, 0%o)\n", key, nsems, semflg)); 976 977 AUDIT_ARG_VALUE(semflg); 978 979 if (sem_find_prison(cred) == NULL) 980 return (ENOSYS); 981 982 mtx_lock(&sem_mtx); 983 if (key != IPC_PRIVATE) { 984 for (semid = 0; semid < seminfo.semmni; semid++) { 985 if ((sema[semid].u.sem_perm.mode & SEM_ALLOC) && 986 sema[semid].cred != NULL && 987 sema[semid].cred->cr_prison == cred->cr_prison && 988 sema[semid].u.sem_perm.key == key) 989 break; 990 } 991 if (semid < seminfo.semmni) { 992 AUDIT_ARG_SVIPC_ID(semid); 993 DPRINTF(("found public key\n")); 994 if ((semflg & IPC_CREAT) && (semflg & IPC_EXCL)) { 995 DPRINTF(("not exclusive\n")); 996 error = EEXIST; 997 goto done2; 998 } 999 if ((error = ipcperm(td, &sema[semid].u.sem_perm, 1000 semflg & 0700))) { 1001 goto done2; 1002 } 1003 if (nsems > 0 && sema[semid].u.sem_nsems < nsems) { 1004 DPRINTF(("too small\n")); 1005 error = EINVAL; 1006 goto done2; 1007 } 1008 #ifdef MAC 1009 error = mac_sysvsem_check_semget(cred, &sema[semid]); 1010 if (error != 0) 1011 goto done2; 1012 #endif 1013 goto found; 1014 } 1015 } 1016 1017 DPRINTF(("need to allocate the semid_kernel\n")); 1018 if (key == IPC_PRIVATE || (semflg & IPC_CREAT)) { 1019 if (nsems <= 0 || nsems > seminfo.semmsl) { 1020 DPRINTF(("nsems out of range (0<%d<=%d)\n", nsems, 1021 seminfo.semmsl)); 1022 error = EINVAL; 1023 goto done2; 1024 } 1025 if (nsems > seminfo.semmns - semtot) { 1026 DPRINTF(( 1027 "not enough semaphores left (need %d, got %d)\n", 1028 nsems, seminfo.semmns - semtot)); 1029 error = ENOSPC; 1030 goto done2; 1031 } 1032 for (semid = 0; semid < seminfo.semmni; semid++) { 1033 if ((sema[semid].u.sem_perm.mode & SEM_ALLOC) == 0) 1034 break; 1035 } 1036 if (semid == seminfo.semmni) { 1037 DPRINTF(("no more semid_kernel's available\n")); 1038 error = ENOSPC; 1039 goto done2; 1040 } 1041 #ifdef RACCT 1042 if (racct_enable) { 1043 PROC_LOCK(td->td_proc); 1044 error = racct_add(td->td_proc, RACCT_NSEM, nsems); 1045 PROC_UNLOCK(td->td_proc); 1046 if (error != 0) { 1047 error = ENOSPC; 1048 goto done2; 1049 } 1050 } 1051 #endif 1052 DPRINTF(("semid %d is available\n", semid)); 1053 mtx_lock(&sema_mtx[semid]); 1054 KASSERT((sema[semid].u.sem_perm.mode & SEM_ALLOC) == 0, 1055 ("Lost semaphore %d", semid)); 1056 sema[semid].u.sem_perm.key = key; 1057 sema[semid].u.sem_perm.cuid = cred->cr_uid; 1058 sema[semid].u.sem_perm.uid = cred->cr_uid; 1059 sema[semid].u.sem_perm.cgid = cred->cr_gid; 1060 sema[semid].u.sem_perm.gid = cred->cr_gid; 1061 sema[semid].u.sem_perm.mode = (semflg & 0777) | SEM_ALLOC; 1062 sema[semid].cred = crhold(cred); 1063 sema[semid].u.sem_perm.seq = 1064 (sema[semid].u.sem_perm.seq + 1) & 0x7fff; 1065 sema[semid].u.sem_nsems = nsems; 1066 sema[semid].u.sem_otime = 0; 1067 sema[semid].u.sem_ctime = time_second; 1068 sema[semid].u.__sem_base = &sem[semtot]; 1069 semtot += nsems; 1070 bzero(sema[semid].u.__sem_base, 1071 sizeof(sema[semid].u.__sem_base[0])*nsems); 1072 #ifdef MAC 1073 mac_sysvsem_create(cred, &sema[semid]); 1074 #endif 1075 mtx_unlock(&sema_mtx[semid]); 1076 DPRINTF(("sembase = %p, next = %p\n", 1077 sema[semid].u.__sem_base, &sem[semtot])); 1078 } else { 1079 DPRINTF(("didn't find it and wasn't asked to create it\n")); 1080 error = ENOENT; 1081 goto done2; 1082 } 1083 1084 found: 1085 td->td_retval[0] = IXSEQ_TO_IPCID(semid, sema[semid].u.sem_perm); 1086 done2: 1087 mtx_unlock(&sem_mtx); 1088 return (error); 1089 } 1090 1091 #ifndef _SYS_SYSPROTO_H_ 1092 struct semop_args { 1093 int semid; 1094 struct sembuf *sops; 1095 size_t nsops; 1096 }; 1097 #endif 1098 int 1099 sys_semop(struct thread *td, struct semop_args *uap) 1100 { 1101 #define SMALL_SOPS 8 1102 struct sembuf small_sops[SMALL_SOPS]; 1103 int semid = uap->semid; 1104 size_t nsops = uap->nsops; 1105 struct prison *rpr; 1106 struct sembuf *sops; 1107 struct semid_kernel *semakptr; 1108 struct sembuf *sopptr = NULL; 1109 struct sem *semptr = NULL; 1110 struct sem_undo *suptr; 1111 struct mtx *sema_mtxp; 1112 size_t i, j, k; 1113 int error; 1114 int do_wakeup, do_undos; 1115 unsigned short seq; 1116 1117 #ifdef SEM_DEBUG 1118 sops = NULL; 1119 #endif 1120 DPRINTF(("call to semop(%d, %p, %u)\n", semid, sops, nsops)); 1121 1122 AUDIT_ARG_SVIPC_ID(semid); 1123 1124 rpr = sem_find_prison(td->td_ucred); 1125 if (sem == NULL) 1126 return (ENOSYS); 1127 1128 semid = IPCID_TO_IX(semid); /* Convert back to zero origin */ 1129 1130 if (semid < 0 || semid >= seminfo.semmni) 1131 return (EINVAL); 1132 1133 /* Allocate memory for sem_ops */ 1134 if (nsops <= SMALL_SOPS) 1135 sops = small_sops; 1136 else if (nsops > seminfo.semopm) { 1137 DPRINTF(("too many sops (max=%d, nsops=%d)\n", seminfo.semopm, 1138 nsops)); 1139 return (E2BIG); 1140 } else { 1141 #ifdef RACCT 1142 if (racct_enable) { 1143 PROC_LOCK(td->td_proc); 1144 if (nsops > 1145 racct_get_available(td->td_proc, RACCT_NSEMOP)) { 1146 PROC_UNLOCK(td->td_proc); 1147 return (E2BIG); 1148 } 1149 PROC_UNLOCK(td->td_proc); 1150 } 1151 #endif 1152 1153 sops = malloc(nsops * sizeof(*sops), M_TEMP, M_WAITOK); 1154 } 1155 if ((error = copyin(uap->sops, sops, nsops * sizeof(sops[0]))) != 0) { 1156 DPRINTF(("error = %d from copyin(%p, %p, %d)\n", error, 1157 uap->sops, sops, nsops * sizeof(sops[0]))); 1158 if (sops != small_sops) 1159 free(sops, M_TEMP); 1160 return (error); 1161 } 1162 1163 semakptr = &sema[semid]; 1164 sema_mtxp = &sema_mtx[semid]; 1165 mtx_lock(sema_mtxp); 1166 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0) { 1167 error = EINVAL; 1168 goto done2; 1169 } 1170 seq = semakptr->u.sem_perm.seq; 1171 if (seq != IPCID_TO_SEQ(uap->semid)) { 1172 error = EINVAL; 1173 goto done2; 1174 } 1175 if ((error = sem_prison_cansee(rpr, semakptr)) != 0) 1176 goto done2; 1177 /* 1178 * Initial pass through sops to see what permissions are needed. 1179 * Also perform any checks that don't need repeating on each 1180 * attempt to satisfy the request vector. 1181 */ 1182 j = 0; /* permission needed */ 1183 do_undos = 0; 1184 for (i = 0; i < nsops; i++) { 1185 sopptr = &sops[i]; 1186 if (sopptr->sem_num >= semakptr->u.sem_nsems) { 1187 error = EFBIG; 1188 goto done2; 1189 } 1190 if (sopptr->sem_flg & SEM_UNDO && sopptr->sem_op != 0) 1191 do_undos = 1; 1192 j |= (sopptr->sem_op == 0) ? SEM_R : SEM_A; 1193 } 1194 1195 if ((error = ipcperm(td, &semakptr->u.sem_perm, j))) { 1196 DPRINTF(("error = %d from ipaccess\n", error)); 1197 goto done2; 1198 } 1199 #ifdef MAC 1200 error = mac_sysvsem_check_semop(td->td_ucred, semakptr, j); 1201 if (error != 0) 1202 goto done2; 1203 #endif 1204 1205 /* 1206 * Loop trying to satisfy the vector of requests. 1207 * If we reach a point where we must wait, any requests already 1208 * performed are rolled back and we go to sleep until some other 1209 * process wakes us up. At this point, we start all over again. 1210 * 1211 * This ensures that from the perspective of other tasks, a set 1212 * of requests is atomic (never partially satisfied). 1213 */ 1214 for (;;) { 1215 do_wakeup = 0; 1216 error = 0; /* error return if necessary */ 1217 1218 for (i = 0; i < nsops; i++) { 1219 sopptr = &sops[i]; 1220 semptr = &semakptr->u.__sem_base[sopptr->sem_num]; 1221 1222 DPRINTF(( 1223 "semop: semakptr=%p, __sem_base=%p, " 1224 "semptr=%p, sem[%d]=%d : op=%d, flag=%s\n", 1225 semakptr, semakptr->u.__sem_base, semptr, 1226 sopptr->sem_num, semptr->semval, sopptr->sem_op, 1227 (sopptr->sem_flg & IPC_NOWAIT) ? 1228 "nowait" : "wait")); 1229 1230 if (sopptr->sem_op < 0) { 1231 if (semptr->semval + sopptr->sem_op < 0) { 1232 DPRINTF(("semop: can't do it now\n")); 1233 break; 1234 } else { 1235 semptr->semval += sopptr->sem_op; 1236 if (semptr->semval == 0 && 1237 semptr->semzcnt > 0) 1238 do_wakeup = 1; 1239 } 1240 } else if (sopptr->sem_op == 0) { 1241 if (semptr->semval != 0) { 1242 DPRINTF(("semop: not zero now\n")); 1243 break; 1244 } 1245 } else if (semptr->semval + sopptr->sem_op > 1246 seminfo.semvmx) { 1247 error = ERANGE; 1248 break; 1249 } else { 1250 if (semptr->semncnt > 0) 1251 do_wakeup = 1; 1252 semptr->semval += sopptr->sem_op; 1253 } 1254 } 1255 1256 /* 1257 * Did we get through the entire vector? 1258 */ 1259 if (i >= nsops) 1260 goto done; 1261 1262 /* 1263 * No ... rollback anything that we've already done 1264 */ 1265 DPRINTF(("semop: rollback 0 through %d\n", i-1)); 1266 for (j = 0; j < i; j++) 1267 semakptr->u.__sem_base[sops[j].sem_num].semval -= 1268 sops[j].sem_op; 1269 1270 /* If we detected an error, return it */ 1271 if (error != 0) 1272 goto done2; 1273 1274 /* 1275 * If the request that we couldn't satisfy has the 1276 * NOWAIT flag set then return with EAGAIN. 1277 */ 1278 if (sopptr->sem_flg & IPC_NOWAIT) { 1279 error = EAGAIN; 1280 goto done2; 1281 } 1282 1283 if (sopptr->sem_op == 0) 1284 semptr->semzcnt++; 1285 else 1286 semptr->semncnt++; 1287 1288 DPRINTF(("semop: good night!\n")); 1289 error = msleep(semakptr, sema_mtxp, (PZERO - 4) | PCATCH, 1290 "semwait", 0); 1291 DPRINTF(("semop: good morning (error=%d)!\n", error)); 1292 /* return code is checked below, after sem[nz]cnt-- */ 1293 1294 /* 1295 * Make sure that the semaphore still exists 1296 */ 1297 seq = semakptr->u.sem_perm.seq; 1298 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 || 1299 seq != IPCID_TO_SEQ(uap->semid)) { 1300 error = EIDRM; 1301 goto done2; 1302 } 1303 1304 /* 1305 * Renew the semaphore's pointer after wakeup since 1306 * during msleep __sem_base may have been modified and semptr 1307 * is not valid any more 1308 */ 1309 semptr = &semakptr->u.__sem_base[sopptr->sem_num]; 1310 1311 /* 1312 * The semaphore is still alive. Readjust the count of 1313 * waiting processes. 1314 */ 1315 if (sopptr->sem_op == 0) 1316 semptr->semzcnt--; 1317 else 1318 semptr->semncnt--; 1319 1320 /* 1321 * Is it really morning, or was our sleep interrupted? 1322 * (Delayed check of msleep() return code because we 1323 * need to decrement sem[nz]cnt either way.) 1324 */ 1325 if (error != 0) { 1326 error = EINTR; 1327 goto done2; 1328 } 1329 DPRINTF(("semop: good morning!\n")); 1330 } 1331 1332 done: 1333 /* 1334 * Process any SEM_UNDO requests. 1335 */ 1336 if (do_undos) { 1337 SEMUNDO_LOCK(); 1338 suptr = NULL; 1339 for (i = 0; i < nsops; i++) { 1340 /* 1341 * We only need to deal with SEM_UNDO's for non-zero 1342 * op's. 1343 */ 1344 int adjval; 1345 1346 if ((sops[i].sem_flg & SEM_UNDO) == 0) 1347 continue; 1348 adjval = sops[i].sem_op; 1349 if (adjval == 0) 1350 continue; 1351 error = semundo_adjust(td, &suptr, semid, seq, 1352 sops[i].sem_num, -adjval); 1353 if (error == 0) 1354 continue; 1355 1356 /* 1357 * Oh-Oh! We ran out of either sem_undo's or undo's. 1358 * Rollback the adjustments to this point and then 1359 * rollback the semaphore ups and down so we can return 1360 * with an error with all structures restored. We 1361 * rollback the undo's in the exact reverse order that 1362 * we applied them. This guarantees that we won't run 1363 * out of space as we roll things back out. 1364 */ 1365 for (j = 0; j < i; j++) { 1366 k = i - j - 1; 1367 if ((sops[k].sem_flg & SEM_UNDO) == 0) 1368 continue; 1369 adjval = sops[k].sem_op; 1370 if (adjval == 0) 1371 continue; 1372 if (semundo_adjust(td, &suptr, semid, seq, 1373 sops[k].sem_num, adjval) != 0) 1374 panic("semop - can't undo undos"); 1375 } 1376 1377 for (j = 0; j < nsops; j++) 1378 semakptr->u.__sem_base[sops[j].sem_num].semval -= 1379 sops[j].sem_op; 1380 1381 DPRINTF(("error = %d from semundo_adjust\n", error)); 1382 SEMUNDO_UNLOCK(); 1383 goto done2; 1384 } /* loop through the sops */ 1385 SEMUNDO_UNLOCK(); 1386 } /* if (do_undos) */ 1387 1388 /* We're definitely done - set the sempid's and time */ 1389 for (i = 0; i < nsops; i++) { 1390 sopptr = &sops[i]; 1391 semptr = &semakptr->u.__sem_base[sopptr->sem_num]; 1392 semptr->sempid = td->td_proc->p_pid; 1393 } 1394 semakptr->u.sem_otime = time_second; 1395 1396 /* 1397 * Do a wakeup if any semaphore was up'd whilst something was 1398 * sleeping on it. 1399 */ 1400 if (do_wakeup) { 1401 DPRINTF(("semop: doing wakeup\n")); 1402 wakeup(semakptr); 1403 DPRINTF(("semop: back from wakeup\n")); 1404 } 1405 DPRINTF(("semop: done\n")); 1406 td->td_retval[0] = 0; 1407 done2: 1408 mtx_unlock(sema_mtxp); 1409 if (sops != small_sops) 1410 free(sops, M_TEMP); 1411 return (error); 1412 } 1413 1414 /* 1415 * Go through the undo structures for this process and apply the adjustments to 1416 * semaphores. 1417 */ 1418 static void 1419 semexit_myhook(void *arg, struct proc *p) 1420 { 1421 struct sem_undo *suptr; 1422 struct semid_kernel *semakptr; 1423 struct mtx *sema_mtxp; 1424 int semid, semnum, adjval, ix; 1425 unsigned short seq; 1426 1427 /* 1428 * Go through the chain of undo vectors looking for one 1429 * associated with this process. 1430 */ 1431 if (LIST_EMPTY(&semu_list)) 1432 return; 1433 SEMUNDO_LOCK(); 1434 LIST_FOREACH(suptr, &semu_list, un_next) { 1435 if (suptr->un_proc == p) 1436 break; 1437 } 1438 if (suptr == NULL) { 1439 SEMUNDO_UNLOCK(); 1440 return; 1441 } 1442 LIST_REMOVE(suptr, un_next); 1443 1444 DPRINTF(("proc @%p has undo structure with %d entries\n", p, 1445 suptr->un_cnt)); 1446 1447 /* 1448 * If there are any active undo elements then process them. 1449 */ 1450 if (suptr->un_cnt > 0) { 1451 SEMUNDO_UNLOCK(); 1452 for (ix = 0; ix < suptr->un_cnt; ix++) { 1453 semid = suptr->un_ent[ix].un_id; 1454 semnum = suptr->un_ent[ix].un_num; 1455 adjval = suptr->un_ent[ix].un_adjval; 1456 seq = suptr->un_ent[ix].un_seq; 1457 semakptr = &sema[semid]; 1458 sema_mtxp = &sema_mtx[semid]; 1459 1460 mtx_lock(sema_mtxp); 1461 if ((semakptr->u.sem_perm.mode & SEM_ALLOC) == 0 || 1462 (semakptr->u.sem_perm.seq != seq)) { 1463 mtx_unlock(sema_mtxp); 1464 continue; 1465 } 1466 if (semnum >= semakptr->u.sem_nsems) 1467 panic("semexit - semnum out of range"); 1468 1469 DPRINTF(( 1470 "semexit: %p id=%d num=%d(adj=%d) ; sem=%d\n", 1471 suptr->un_proc, suptr->un_ent[ix].un_id, 1472 suptr->un_ent[ix].un_num, 1473 suptr->un_ent[ix].un_adjval, 1474 semakptr->u.__sem_base[semnum].semval)); 1475 1476 if (adjval < 0 && semakptr->u.__sem_base[semnum].semval < 1477 -adjval) 1478 semakptr->u.__sem_base[semnum].semval = 0; 1479 else 1480 semakptr->u.__sem_base[semnum].semval += adjval; 1481 1482 wakeup(semakptr); 1483 DPRINTF(("semexit: back from wakeup\n")); 1484 mtx_unlock(sema_mtxp); 1485 } 1486 SEMUNDO_LOCK(); 1487 } 1488 1489 /* 1490 * Deallocate the undo vector. 1491 */ 1492 DPRINTF(("removing vector\n")); 1493 suptr->un_proc = NULL; 1494 suptr->un_cnt = 0; 1495 LIST_INSERT_HEAD(&semu_free_list, suptr, un_next); 1496 SEMUNDO_UNLOCK(); 1497 } 1498 1499 static int 1500 sysctl_sema(SYSCTL_HANDLER_ARGS) 1501 { 1502 struct prison *pr, *rpr; 1503 struct semid_kernel tsemak; 1504 #ifdef COMPAT_FREEBSD32 1505 struct semid_kernel32 tsemak32; 1506 #endif 1507 void *outaddr; 1508 size_t outsize; 1509 int error, i; 1510 1511 pr = req->td->td_ucred->cr_prison; 1512 rpr = sem_find_prison(req->td->td_ucred); 1513 error = 0; 1514 for (i = 0; i < seminfo.semmni; i++) { 1515 mtx_lock(&sema_mtx[i]); 1516 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) == 0 || 1517 rpr == NULL || sem_prison_cansee(rpr, &sema[i]) != 0) 1518 bzero(&tsemak, sizeof(tsemak)); 1519 else { 1520 tsemak = sema[i]; 1521 if (tsemak.cred->cr_prison != pr) 1522 tsemak.u.sem_perm.key = IPC_PRIVATE; 1523 } 1524 mtx_unlock(&sema_mtx[i]); 1525 #ifdef COMPAT_FREEBSD32 1526 if (SV_CURPROC_FLAG(SV_ILP32)) { 1527 bzero(&tsemak32, sizeof(tsemak32)); 1528 freebsd32_ipcperm_out(&tsemak.u.sem_perm, 1529 &tsemak32.u.sem_perm); 1530 /* Don't copy u.__sem_base */ 1531 CP(tsemak, tsemak32, u.sem_nsems); 1532 CP(tsemak, tsemak32, u.sem_otime); 1533 CP(tsemak, tsemak32, u.sem_ctime); 1534 /* Don't copy label or cred */ 1535 outaddr = &tsemak32; 1536 outsize = sizeof(tsemak32); 1537 } else 1538 #endif 1539 { 1540 tsemak.u.__sem_base = NULL; 1541 tsemak.label = NULL; 1542 tsemak.cred = NULL; 1543 outaddr = &tsemak; 1544 outsize = sizeof(tsemak); 1545 } 1546 error = SYSCTL_OUT(req, outaddr, outsize); 1547 if (error != 0) 1548 break; 1549 } 1550 return (error); 1551 } 1552 1553 static int 1554 sem_prison_check(void *obj, void *data) 1555 { 1556 struct prison *pr = obj; 1557 struct prison *prpr; 1558 struct vfsoptlist *opts = data; 1559 int error, jsys; 1560 1561 /* 1562 * sysvsem is a jailsys integer. 1563 * It must be "disable" if the parent jail is disabled. 1564 */ 1565 error = vfs_copyopt(opts, "sysvsem", &jsys, sizeof(jsys)); 1566 if (error != ENOENT) { 1567 if (error != 0) 1568 return (error); 1569 switch (jsys) { 1570 case JAIL_SYS_DISABLE: 1571 break; 1572 case JAIL_SYS_NEW: 1573 case JAIL_SYS_INHERIT: 1574 prison_lock(pr->pr_parent); 1575 prpr = osd_jail_get(pr->pr_parent, sem_prison_slot); 1576 prison_unlock(pr->pr_parent); 1577 if (prpr == NULL) 1578 return (EPERM); 1579 break; 1580 default: 1581 return (EINVAL); 1582 } 1583 } 1584 1585 return (0); 1586 } 1587 1588 static int 1589 sem_prison_set(void *obj, void *data) 1590 { 1591 struct prison *pr = obj; 1592 struct prison *tpr, *orpr, *nrpr, *trpr; 1593 struct vfsoptlist *opts = data; 1594 void *rsv; 1595 int jsys, descend; 1596 1597 /* 1598 * sysvsem controls which jail is the root of the associated sems (this 1599 * jail or same as the parent), or if the feature is available at all. 1600 */ 1601 if (vfs_copyopt(opts, "sysvsem", &jsys, sizeof(jsys)) == ENOENT) 1602 jsys = vfs_flagopt(opts, "allow.sysvipc", NULL, 0) 1603 ? JAIL_SYS_INHERIT 1604 : vfs_flagopt(opts, "allow.nosysvipc", NULL, 0) 1605 ? JAIL_SYS_DISABLE 1606 : -1; 1607 if (jsys == JAIL_SYS_DISABLE) { 1608 prison_lock(pr); 1609 orpr = osd_jail_get(pr, sem_prison_slot); 1610 if (orpr != NULL) 1611 osd_jail_del(pr, sem_prison_slot); 1612 prison_unlock(pr); 1613 if (orpr != NULL) { 1614 if (orpr == pr) 1615 sem_prison_cleanup(pr); 1616 /* Disable all child jails as well. */ 1617 FOREACH_PRISON_DESCENDANT(pr, tpr, descend) { 1618 prison_lock(tpr); 1619 trpr = osd_jail_get(tpr, sem_prison_slot); 1620 if (trpr != NULL) { 1621 osd_jail_del(tpr, sem_prison_slot); 1622 prison_unlock(tpr); 1623 if (trpr == tpr) 1624 sem_prison_cleanup(tpr); 1625 } else { 1626 prison_unlock(tpr); 1627 descend = 0; 1628 } 1629 } 1630 } 1631 } else if (jsys != -1) { 1632 if (jsys == JAIL_SYS_NEW) 1633 nrpr = pr; 1634 else { 1635 prison_lock(pr->pr_parent); 1636 nrpr = osd_jail_get(pr->pr_parent, sem_prison_slot); 1637 prison_unlock(pr->pr_parent); 1638 } 1639 rsv = osd_reserve(sem_prison_slot); 1640 prison_lock(pr); 1641 orpr = osd_jail_get(pr, sem_prison_slot); 1642 if (orpr != nrpr) 1643 (void)osd_jail_set_reserved(pr, sem_prison_slot, rsv, 1644 nrpr); 1645 else 1646 osd_free_reserved(rsv); 1647 prison_unlock(pr); 1648 if (orpr != nrpr) { 1649 if (orpr == pr) 1650 sem_prison_cleanup(pr); 1651 if (orpr != NULL) { 1652 /* Change child jails matching the old root, */ 1653 FOREACH_PRISON_DESCENDANT(pr, tpr, descend) { 1654 prison_lock(tpr); 1655 trpr = osd_jail_get(tpr, 1656 sem_prison_slot); 1657 if (trpr == orpr) { 1658 (void)osd_jail_set(tpr, 1659 sem_prison_slot, nrpr); 1660 prison_unlock(tpr); 1661 if (trpr == tpr) 1662 sem_prison_cleanup(tpr); 1663 } else { 1664 prison_unlock(tpr); 1665 descend = 0; 1666 } 1667 } 1668 } 1669 } 1670 } 1671 1672 return (0); 1673 } 1674 1675 static int 1676 sem_prison_get(void *obj, void *data) 1677 { 1678 struct prison *pr = obj; 1679 struct prison *rpr; 1680 struct vfsoptlist *opts = data; 1681 int error, jsys; 1682 1683 /* Set sysvsem based on the jail's root prison. */ 1684 prison_lock(pr); 1685 rpr = osd_jail_get(pr, sem_prison_slot); 1686 prison_unlock(pr); 1687 jsys = rpr == NULL ? JAIL_SYS_DISABLE 1688 : rpr == pr ? JAIL_SYS_NEW : JAIL_SYS_INHERIT; 1689 error = vfs_setopt(opts, "sysvsem", &jsys, sizeof(jsys)); 1690 if (error == ENOENT) 1691 error = 0; 1692 return (error); 1693 } 1694 1695 static int 1696 sem_prison_remove(void *obj, void *data __unused) 1697 { 1698 struct prison *pr = obj; 1699 struct prison *rpr; 1700 1701 prison_lock(pr); 1702 rpr = osd_jail_get(pr, sem_prison_slot); 1703 prison_unlock(pr); 1704 if (rpr == pr) 1705 sem_prison_cleanup(pr); 1706 return (0); 1707 } 1708 1709 static void 1710 sem_prison_cleanup(struct prison *pr) 1711 { 1712 int i; 1713 1714 /* Remove any sems that belong to this jail. */ 1715 mtx_lock(&sem_mtx); 1716 for (i = 0; i < seminfo.semmni; i++) { 1717 if ((sema[i].u.sem_perm.mode & SEM_ALLOC) && 1718 sema[i].cred != NULL && sema[i].cred->cr_prison == pr) { 1719 mtx_lock(&sema_mtx[i]); 1720 sem_remove(i, NULL); 1721 mtx_unlock(&sema_mtx[i]); 1722 } 1723 } 1724 mtx_unlock(&sem_mtx); 1725 } 1726 1727 SYSCTL_JAIL_PARAM_SYS_NODE(sysvsem, CTLFLAG_RW, "SYSV semaphores"); 1728 1729 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \ 1730 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7) 1731 1732 /* XXX casting to (sy_call_t *) is bogus, as usual. */ 1733 static sy_call_t *semcalls[] = { 1734 (sy_call_t *)freebsd7___semctl, (sy_call_t *)sys_semget, 1735 (sy_call_t *)sys_semop 1736 }; 1737 1738 /* 1739 * Entry point for all SEM calls. 1740 */ 1741 int 1742 sys_semsys(td, uap) 1743 struct thread *td; 1744 /* XXX actually varargs. */ 1745 struct semsys_args /* { 1746 int which; 1747 int a2; 1748 int a3; 1749 int a4; 1750 int a5; 1751 } */ *uap; 1752 { 1753 int error; 1754 1755 AUDIT_ARG_SVIPC_WHICH(uap->which); 1756 if (uap->which < 0 || uap->which >= nitems(semcalls)) 1757 return (EINVAL); 1758 error = (*semcalls[uap->which])(td, &uap->a2); 1759 return (error); 1760 } 1761 1762 #ifndef _SYS_SYSPROTO_H_ 1763 struct freebsd7___semctl_args { 1764 int semid; 1765 int semnum; 1766 int cmd; 1767 union semun_old *arg; 1768 }; 1769 #endif 1770 int 1771 freebsd7___semctl(struct thread *td, struct freebsd7___semctl_args *uap) 1772 { 1773 struct semid_ds_old dsold; 1774 struct semid_ds dsbuf; 1775 union semun_old arg; 1776 union semun semun; 1777 register_t rval; 1778 int error; 1779 1780 switch (uap->cmd) { 1781 case SEM_STAT: 1782 case IPC_SET: 1783 case IPC_STAT: 1784 case GETALL: 1785 case SETVAL: 1786 case SETALL: 1787 error = copyin(uap->arg, &arg, sizeof(arg)); 1788 if (error) 1789 return (error); 1790 break; 1791 } 1792 1793 switch (uap->cmd) { 1794 case SEM_STAT: 1795 case IPC_STAT: 1796 semun.buf = &dsbuf; 1797 break; 1798 case IPC_SET: 1799 error = copyin(arg.buf, &dsold, sizeof(dsold)); 1800 if (error) 1801 return (error); 1802 ipcperm_old2new(&dsold.sem_perm, &dsbuf.sem_perm); 1803 CP(dsold, dsbuf, __sem_base); 1804 CP(dsold, dsbuf, sem_nsems); 1805 CP(dsold, dsbuf, sem_otime); 1806 CP(dsold, dsbuf, sem_ctime); 1807 semun.buf = &dsbuf; 1808 break; 1809 case GETALL: 1810 case SETALL: 1811 semun.array = arg.array; 1812 break; 1813 case SETVAL: 1814 semun.val = arg.val; 1815 break; 1816 } 1817 1818 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun, 1819 &rval); 1820 if (error) 1821 return (error); 1822 1823 switch (uap->cmd) { 1824 case SEM_STAT: 1825 case IPC_STAT: 1826 bzero(&dsold, sizeof(dsold)); 1827 ipcperm_new2old(&dsbuf.sem_perm, &dsold.sem_perm); 1828 CP(dsbuf, dsold, __sem_base); 1829 CP(dsbuf, dsold, sem_nsems); 1830 CP(dsbuf, dsold, sem_otime); 1831 CP(dsbuf, dsold, sem_ctime); 1832 error = copyout(&dsold, arg.buf, sizeof(dsold)); 1833 break; 1834 } 1835 1836 if (error == 0) 1837 td->td_retval[0] = rval; 1838 return (error); 1839 } 1840 1841 #endif /* COMPAT_FREEBSD{4,5,6,7} */ 1842 1843 #ifdef COMPAT_FREEBSD32 1844 1845 int 1846 freebsd32_semsys(struct thread *td, struct freebsd32_semsys_args *uap) 1847 { 1848 1849 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \ 1850 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7) 1851 AUDIT_ARG_SVIPC_WHICH(uap->which); 1852 switch (uap->which) { 1853 case 0: 1854 return (freebsd7_freebsd32___semctl(td, 1855 (struct freebsd7_freebsd32___semctl_args *)&uap->a2)); 1856 default: 1857 return (sys_semsys(td, (struct semsys_args *)uap)); 1858 } 1859 #else 1860 return (nosys(td, NULL)); 1861 #endif 1862 } 1863 1864 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \ 1865 defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7) 1866 int 1867 freebsd7_freebsd32___semctl(struct thread *td, 1868 struct freebsd7_freebsd32___semctl_args *uap) 1869 { 1870 struct semid_ds_old32 dsbuf32; 1871 struct semid_ds dsbuf; 1872 union semun semun; 1873 union semun_old32 arg; 1874 register_t rval; 1875 int error; 1876 1877 switch (uap->cmd) { 1878 case SEM_STAT: 1879 case IPC_SET: 1880 case IPC_STAT: 1881 case GETALL: 1882 case SETVAL: 1883 case SETALL: 1884 error = copyin(uap->arg, &arg, sizeof(arg)); 1885 if (error) 1886 return (error); 1887 break; 1888 } 1889 1890 switch (uap->cmd) { 1891 case SEM_STAT: 1892 case IPC_STAT: 1893 semun.buf = &dsbuf; 1894 break; 1895 case IPC_SET: 1896 error = copyin(PTRIN(arg.buf), &dsbuf32, sizeof(dsbuf32)); 1897 if (error) 1898 return (error); 1899 freebsd32_ipcperm_old_in(&dsbuf32.sem_perm, &dsbuf.sem_perm); 1900 PTRIN_CP(dsbuf32, dsbuf, __sem_base); 1901 CP(dsbuf32, dsbuf, sem_nsems); 1902 CP(dsbuf32, dsbuf, sem_otime); 1903 CP(dsbuf32, dsbuf, sem_ctime); 1904 semun.buf = &dsbuf; 1905 break; 1906 case GETALL: 1907 case SETALL: 1908 semun.array = PTRIN(arg.array); 1909 break; 1910 case SETVAL: 1911 semun.val = arg.val; 1912 break; 1913 } 1914 1915 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun, 1916 &rval); 1917 if (error) 1918 return (error); 1919 1920 switch (uap->cmd) { 1921 case SEM_STAT: 1922 case IPC_STAT: 1923 bzero(&dsbuf32, sizeof(dsbuf32)); 1924 freebsd32_ipcperm_old_out(&dsbuf.sem_perm, &dsbuf32.sem_perm); 1925 PTROUT_CP(dsbuf, dsbuf32, __sem_base); 1926 CP(dsbuf, dsbuf32, sem_nsems); 1927 CP(dsbuf, dsbuf32, sem_otime); 1928 CP(dsbuf, dsbuf32, sem_ctime); 1929 error = copyout(&dsbuf32, PTRIN(arg.buf), sizeof(dsbuf32)); 1930 break; 1931 } 1932 1933 if (error == 0) 1934 td->td_retval[0] = rval; 1935 return (error); 1936 } 1937 #endif 1938 1939 int 1940 freebsd32___semctl(struct thread *td, struct freebsd32___semctl_args *uap) 1941 { 1942 struct semid_ds32 dsbuf32; 1943 struct semid_ds dsbuf; 1944 union semun semun; 1945 union semun32 arg; 1946 register_t rval; 1947 int error; 1948 1949 switch (uap->cmd) { 1950 case SEM_STAT: 1951 case IPC_SET: 1952 case IPC_STAT: 1953 case GETALL: 1954 case SETVAL: 1955 case SETALL: 1956 error = copyin(uap->arg, &arg, sizeof(arg)); 1957 if (error) 1958 return (error); 1959 break; 1960 } 1961 1962 switch (uap->cmd) { 1963 case SEM_STAT: 1964 case IPC_STAT: 1965 semun.buf = &dsbuf; 1966 break; 1967 case IPC_SET: 1968 error = copyin(PTRIN(arg.buf), &dsbuf32, sizeof(dsbuf32)); 1969 if (error) 1970 return (error); 1971 freebsd32_ipcperm_in(&dsbuf32.sem_perm, &dsbuf.sem_perm); 1972 PTRIN_CP(dsbuf32, dsbuf, __sem_base); 1973 CP(dsbuf32, dsbuf, sem_nsems); 1974 CP(dsbuf32, dsbuf, sem_otime); 1975 CP(dsbuf32, dsbuf, sem_ctime); 1976 semun.buf = &dsbuf; 1977 break; 1978 case GETALL: 1979 case SETALL: 1980 semun.array = PTRIN(arg.array); 1981 break; 1982 case SETVAL: 1983 semun.val = arg.val; 1984 break; 1985 } 1986 1987 error = kern_semctl(td, uap->semid, uap->semnum, uap->cmd, &semun, 1988 &rval); 1989 if (error) 1990 return (error); 1991 1992 switch (uap->cmd) { 1993 case SEM_STAT: 1994 case IPC_STAT: 1995 bzero(&dsbuf32, sizeof(dsbuf32)); 1996 freebsd32_ipcperm_out(&dsbuf.sem_perm, &dsbuf32.sem_perm); 1997 PTROUT_CP(dsbuf, dsbuf32, __sem_base); 1998 CP(dsbuf, dsbuf32, sem_nsems); 1999 CP(dsbuf, dsbuf32, sem_otime); 2000 CP(dsbuf, dsbuf32, sem_ctime); 2001 error = copyout(&dsbuf32, PTRIN(arg.buf), sizeof(dsbuf32)); 2002 break; 2003 } 2004 2005 if (error == 0) 2006 td->td_retval[0] = rval; 2007 return (error); 2008 } 2009 2010 #endif /* COMPAT_FREEBSD32 */ 2011