1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_compat.h" 41 #include "opt_kdtrace.h" 42 #include "opt_ktrace.h" 43 #include "opt_core.h" 44 #include "opt_procdesc.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/signalvar.h> 49 #include <sys/vnode.h> 50 #include <sys/acct.h> 51 #include <sys/capability.h> 52 #include <sys/condvar.h> 53 #include <sys/event.h> 54 #include <sys/fcntl.h> 55 #include <sys/imgact.h> 56 #include <sys/kernel.h> 57 #include <sys/ktr.h> 58 #include <sys/ktrace.h> 59 #include <sys/lock.h> 60 #include <sys/malloc.h> 61 #include <sys/mutex.h> 62 #include <sys/namei.h> 63 #include <sys/proc.h> 64 #include <sys/procdesc.h> 65 #include <sys/posix4.h> 66 #include <sys/pioctl.h> 67 #include <sys/racct.h> 68 #include <sys/resourcevar.h> 69 #include <sys/sdt.h> 70 #include <sys/sbuf.h> 71 #include <sys/sleepqueue.h> 72 #include <sys/smp.h> 73 #include <sys/stat.h> 74 #include <sys/sx.h> 75 #include <sys/syscallsubr.h> 76 #include <sys/sysctl.h> 77 #include <sys/sysent.h> 78 #include <sys/syslog.h> 79 #include <sys/sysproto.h> 80 #include <sys/timers.h> 81 #include <sys/unistd.h> 82 #include <sys/wait.h> 83 #include <vm/vm.h> 84 #include <vm/vm_extern.h> 85 #include <vm/uma.h> 86 87 #include <sys/jail.h> 88 89 #include <machine/cpu.h> 90 91 #include <security/audit/audit.h> 92 93 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */ 94 95 SDT_PROVIDER_DECLARE(proc); 96 SDT_PROBE_DEFINE3(proc, kernel, , signal_send, signal-send, "struct thread *", 97 "struct proc *", "int"); 98 SDT_PROBE_DEFINE2(proc, kernel, , signal_clear, signal-clear, "int", 99 "ksiginfo_t *"); 100 SDT_PROBE_DEFINE3(proc, kernel, , signal_discard, signal-discard, 101 "struct thread *", "struct proc *", "int"); 102 103 static int coredump(struct thread *); 104 static int killpg1(struct thread *td, int sig, int pgid, int all, 105 ksiginfo_t *ksi); 106 static int issignal(struct thread *td); 107 static int sigprop(int sig); 108 static void tdsigwakeup(struct thread *, int, sig_t, int); 109 static void sig_suspend_threads(struct thread *, struct proc *, int); 110 static int filt_sigattach(struct knote *kn); 111 static void filt_sigdetach(struct knote *kn); 112 static int filt_signal(struct knote *kn, long hint); 113 static struct thread *sigtd(struct proc *p, int sig, int prop); 114 static void sigqueue_start(void); 115 116 static uma_zone_t ksiginfo_zone = NULL; 117 struct filterops sig_filtops = { 118 .f_isfd = 0, 119 .f_attach = filt_sigattach, 120 .f_detach = filt_sigdetach, 121 .f_event = filt_signal, 122 }; 123 124 static int kern_logsigexit = 1; 125 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW, 126 &kern_logsigexit, 0, 127 "Log processes quitting on abnormal signals to syslog(3)"); 128 129 static int kern_forcesigexit = 1; 130 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW, 131 &kern_forcesigexit, 0, "Force trap signal to be handled"); 132 133 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0, 134 "POSIX real time signal"); 135 136 static int max_pending_per_proc = 128; 137 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW, 138 &max_pending_per_proc, 0, "Max pending signals per proc"); 139 140 static int preallocate_siginfo = 1024; 141 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo); 142 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD, 143 &preallocate_siginfo, 0, "Preallocated signal memory size"); 144 145 static int signal_overflow = 0; 146 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD, 147 &signal_overflow, 0, "Number of signals overflew"); 148 149 static int signal_alloc_fail = 0; 150 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD, 151 &signal_alloc_fail, 0, "signals failed to be allocated"); 152 153 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL); 154 155 /* 156 * Policy -- Can ucred cr1 send SIGIO to process cr2? 157 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG 158 * in the right situations. 159 */ 160 #define CANSIGIO(cr1, cr2) \ 161 ((cr1)->cr_uid == 0 || \ 162 (cr1)->cr_ruid == (cr2)->cr_ruid || \ 163 (cr1)->cr_uid == (cr2)->cr_ruid || \ 164 (cr1)->cr_ruid == (cr2)->cr_uid || \ 165 (cr1)->cr_uid == (cr2)->cr_uid) 166 167 static int sugid_coredump; 168 TUNABLE_INT("kern.sugid_coredump", &sugid_coredump); 169 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW, 170 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core"); 171 172 static int capmode_coredump; 173 TUNABLE_INT("kern.capmode_coredump", &capmode_coredump); 174 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RW, 175 &capmode_coredump, 0, "Allow processes in capability mode to dump core"); 176 177 static int do_coredump = 1; 178 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW, 179 &do_coredump, 0, "Enable/Disable coredumps"); 180 181 static int set_core_nodump_flag = 0; 182 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag, 183 0, "Enable setting the NODUMP flag on coredump files"); 184 185 /* 186 * Signal properties and actions. 187 * The array below categorizes the signals and their default actions 188 * according to the following properties: 189 */ 190 #define SA_KILL 0x01 /* terminates process by default */ 191 #define SA_CORE 0x02 /* ditto and coredumps */ 192 #define SA_STOP 0x04 /* suspend process */ 193 #define SA_TTYSTOP 0x08 /* ditto, from tty */ 194 #define SA_IGNORE 0x10 /* ignore by default */ 195 #define SA_CONT 0x20 /* continue if suspended */ 196 #define SA_CANTMASK 0x40 /* non-maskable, catchable */ 197 198 static int sigproptbl[NSIG] = { 199 SA_KILL, /* SIGHUP */ 200 SA_KILL, /* SIGINT */ 201 SA_KILL|SA_CORE, /* SIGQUIT */ 202 SA_KILL|SA_CORE, /* SIGILL */ 203 SA_KILL|SA_CORE, /* SIGTRAP */ 204 SA_KILL|SA_CORE, /* SIGABRT */ 205 SA_KILL|SA_CORE, /* SIGEMT */ 206 SA_KILL|SA_CORE, /* SIGFPE */ 207 SA_KILL, /* SIGKILL */ 208 SA_KILL|SA_CORE, /* SIGBUS */ 209 SA_KILL|SA_CORE, /* SIGSEGV */ 210 SA_KILL|SA_CORE, /* SIGSYS */ 211 SA_KILL, /* SIGPIPE */ 212 SA_KILL, /* SIGALRM */ 213 SA_KILL, /* SIGTERM */ 214 SA_IGNORE, /* SIGURG */ 215 SA_STOP, /* SIGSTOP */ 216 SA_STOP|SA_TTYSTOP, /* SIGTSTP */ 217 SA_IGNORE|SA_CONT, /* SIGCONT */ 218 SA_IGNORE, /* SIGCHLD */ 219 SA_STOP|SA_TTYSTOP, /* SIGTTIN */ 220 SA_STOP|SA_TTYSTOP, /* SIGTTOU */ 221 SA_IGNORE, /* SIGIO */ 222 SA_KILL, /* SIGXCPU */ 223 SA_KILL, /* SIGXFSZ */ 224 SA_KILL, /* SIGVTALRM */ 225 SA_KILL, /* SIGPROF */ 226 SA_IGNORE, /* SIGWINCH */ 227 SA_IGNORE, /* SIGINFO */ 228 SA_KILL, /* SIGUSR1 */ 229 SA_KILL, /* SIGUSR2 */ 230 }; 231 232 static void reschedule_signals(struct proc *p, sigset_t block, int flags); 233 234 static void 235 sigqueue_start(void) 236 { 237 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t), 238 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 239 uma_prealloc(ksiginfo_zone, preallocate_siginfo); 240 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS); 241 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1); 242 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc); 243 } 244 245 ksiginfo_t * 246 ksiginfo_alloc(int wait) 247 { 248 int flags; 249 250 flags = M_ZERO; 251 if (! wait) 252 flags |= M_NOWAIT; 253 if (ksiginfo_zone != NULL) 254 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags)); 255 return (NULL); 256 } 257 258 void 259 ksiginfo_free(ksiginfo_t *ksi) 260 { 261 uma_zfree(ksiginfo_zone, ksi); 262 } 263 264 static __inline int 265 ksiginfo_tryfree(ksiginfo_t *ksi) 266 { 267 if (!(ksi->ksi_flags & KSI_EXT)) { 268 uma_zfree(ksiginfo_zone, ksi); 269 return (1); 270 } 271 return (0); 272 } 273 274 void 275 sigqueue_init(sigqueue_t *list, struct proc *p) 276 { 277 SIGEMPTYSET(list->sq_signals); 278 SIGEMPTYSET(list->sq_kill); 279 TAILQ_INIT(&list->sq_list); 280 list->sq_proc = p; 281 list->sq_flags = SQ_INIT; 282 } 283 284 /* 285 * Get a signal's ksiginfo. 286 * Return: 287 * 0 - signal not found 288 * others - signal number 289 */ 290 static int 291 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si) 292 { 293 struct proc *p = sq->sq_proc; 294 struct ksiginfo *ksi, *next; 295 int count = 0; 296 297 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited")); 298 299 if (!SIGISMEMBER(sq->sq_signals, signo)) 300 return (0); 301 302 if (SIGISMEMBER(sq->sq_kill, signo)) { 303 count++; 304 SIGDELSET(sq->sq_kill, signo); 305 } 306 307 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) { 308 if (ksi->ksi_signo == signo) { 309 if (count == 0) { 310 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); 311 ksi->ksi_sigq = NULL; 312 ksiginfo_copy(ksi, si); 313 if (ksiginfo_tryfree(ksi) && p != NULL) 314 p->p_pendingcnt--; 315 } 316 if (++count > 1) 317 break; 318 } 319 } 320 321 if (count <= 1) 322 SIGDELSET(sq->sq_signals, signo); 323 si->ksi_signo = signo; 324 return (signo); 325 } 326 327 void 328 sigqueue_take(ksiginfo_t *ksi) 329 { 330 struct ksiginfo *kp; 331 struct proc *p; 332 sigqueue_t *sq; 333 334 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL) 335 return; 336 337 p = sq->sq_proc; 338 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); 339 ksi->ksi_sigq = NULL; 340 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL) 341 p->p_pendingcnt--; 342 343 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL; 344 kp = TAILQ_NEXT(kp, ksi_link)) { 345 if (kp->ksi_signo == ksi->ksi_signo) 346 break; 347 } 348 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo)) 349 SIGDELSET(sq->sq_signals, ksi->ksi_signo); 350 } 351 352 static int 353 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si) 354 { 355 struct proc *p = sq->sq_proc; 356 struct ksiginfo *ksi; 357 int ret = 0; 358 359 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited")); 360 361 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) { 362 SIGADDSET(sq->sq_kill, signo); 363 goto out_set_bit; 364 } 365 366 /* directly insert the ksi, don't copy it */ 367 if (si->ksi_flags & KSI_INS) { 368 if (si->ksi_flags & KSI_HEAD) 369 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link); 370 else 371 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link); 372 si->ksi_sigq = sq; 373 goto out_set_bit; 374 } 375 376 if (__predict_false(ksiginfo_zone == NULL)) { 377 SIGADDSET(sq->sq_kill, signo); 378 goto out_set_bit; 379 } 380 381 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) { 382 signal_overflow++; 383 ret = EAGAIN; 384 } else if ((ksi = ksiginfo_alloc(0)) == NULL) { 385 signal_alloc_fail++; 386 ret = EAGAIN; 387 } else { 388 if (p != NULL) 389 p->p_pendingcnt++; 390 ksiginfo_copy(si, ksi); 391 ksi->ksi_signo = signo; 392 if (si->ksi_flags & KSI_HEAD) 393 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link); 394 else 395 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link); 396 ksi->ksi_sigq = sq; 397 } 398 399 if ((si->ksi_flags & KSI_TRAP) != 0 || 400 (si->ksi_flags & KSI_SIGQ) == 0) { 401 if (ret != 0) 402 SIGADDSET(sq->sq_kill, signo); 403 ret = 0; 404 goto out_set_bit; 405 } 406 407 if (ret != 0) 408 return (ret); 409 410 out_set_bit: 411 SIGADDSET(sq->sq_signals, signo); 412 return (ret); 413 } 414 415 void 416 sigqueue_flush(sigqueue_t *sq) 417 { 418 struct proc *p = sq->sq_proc; 419 ksiginfo_t *ksi; 420 421 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited")); 422 423 if (p != NULL) 424 PROC_LOCK_ASSERT(p, MA_OWNED); 425 426 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) { 427 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); 428 ksi->ksi_sigq = NULL; 429 if (ksiginfo_tryfree(ksi) && p != NULL) 430 p->p_pendingcnt--; 431 } 432 433 SIGEMPTYSET(sq->sq_signals); 434 SIGEMPTYSET(sq->sq_kill); 435 } 436 437 static void 438 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set) 439 { 440 sigset_t tmp; 441 struct proc *p1, *p2; 442 ksiginfo_t *ksi, *next; 443 444 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited")); 445 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited")); 446 p1 = src->sq_proc; 447 p2 = dst->sq_proc; 448 /* Move siginfo to target list */ 449 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) { 450 if (SIGISMEMBER(*set, ksi->ksi_signo)) { 451 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link); 452 if (p1 != NULL) 453 p1->p_pendingcnt--; 454 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link); 455 ksi->ksi_sigq = dst; 456 if (p2 != NULL) 457 p2->p_pendingcnt++; 458 } 459 } 460 461 /* Move pending bits to target list */ 462 tmp = src->sq_kill; 463 SIGSETAND(tmp, *set); 464 SIGSETOR(dst->sq_kill, tmp); 465 SIGSETNAND(src->sq_kill, tmp); 466 467 tmp = src->sq_signals; 468 SIGSETAND(tmp, *set); 469 SIGSETOR(dst->sq_signals, tmp); 470 SIGSETNAND(src->sq_signals, tmp); 471 } 472 473 #if 0 474 static void 475 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo) 476 { 477 sigset_t set; 478 479 SIGEMPTYSET(set); 480 SIGADDSET(set, signo); 481 sigqueue_move_set(src, dst, &set); 482 } 483 #endif 484 485 static void 486 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set) 487 { 488 struct proc *p = sq->sq_proc; 489 ksiginfo_t *ksi, *next; 490 491 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited")); 492 493 /* Remove siginfo queue */ 494 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) { 495 if (SIGISMEMBER(*set, ksi->ksi_signo)) { 496 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link); 497 ksi->ksi_sigq = NULL; 498 if (ksiginfo_tryfree(ksi) && p != NULL) 499 p->p_pendingcnt--; 500 } 501 } 502 SIGSETNAND(sq->sq_kill, *set); 503 SIGSETNAND(sq->sq_signals, *set); 504 } 505 506 void 507 sigqueue_delete(sigqueue_t *sq, int signo) 508 { 509 sigset_t set; 510 511 SIGEMPTYSET(set); 512 SIGADDSET(set, signo); 513 sigqueue_delete_set(sq, &set); 514 } 515 516 /* Remove a set of signals for a process */ 517 static void 518 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set) 519 { 520 sigqueue_t worklist; 521 struct thread *td0; 522 523 PROC_LOCK_ASSERT(p, MA_OWNED); 524 525 sigqueue_init(&worklist, NULL); 526 sigqueue_move_set(&p->p_sigqueue, &worklist, set); 527 528 FOREACH_THREAD_IN_PROC(p, td0) 529 sigqueue_move_set(&td0->td_sigqueue, &worklist, set); 530 531 sigqueue_flush(&worklist); 532 } 533 534 void 535 sigqueue_delete_proc(struct proc *p, int signo) 536 { 537 sigset_t set; 538 539 SIGEMPTYSET(set); 540 SIGADDSET(set, signo); 541 sigqueue_delete_set_proc(p, &set); 542 } 543 544 static void 545 sigqueue_delete_stopmask_proc(struct proc *p) 546 { 547 sigset_t set; 548 549 SIGEMPTYSET(set); 550 SIGADDSET(set, SIGSTOP); 551 SIGADDSET(set, SIGTSTP); 552 SIGADDSET(set, SIGTTIN); 553 SIGADDSET(set, SIGTTOU); 554 sigqueue_delete_set_proc(p, &set); 555 } 556 557 /* 558 * Determine signal that should be delivered to thread td, the current 559 * thread, 0 if none. If there is a pending stop signal with default 560 * action, the process stops in issignal(). 561 */ 562 int 563 cursig(struct thread *td) 564 { 565 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 566 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED); 567 THREAD_LOCK_ASSERT(td, MA_NOTOWNED); 568 return (SIGPENDING(td) ? issignal(td) : 0); 569 } 570 571 /* 572 * Arrange for ast() to handle unmasked pending signals on return to user 573 * mode. This must be called whenever a signal is added to td_sigqueue or 574 * unmasked in td_sigmask. 575 */ 576 void 577 signotify(struct thread *td) 578 { 579 struct proc *p; 580 581 p = td->td_proc; 582 583 PROC_LOCK_ASSERT(p, MA_OWNED); 584 585 if (SIGPENDING(td)) { 586 thread_lock(td); 587 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING; 588 thread_unlock(td); 589 } 590 } 591 592 int 593 sigonstack(size_t sp) 594 { 595 struct thread *td = curthread; 596 597 return ((td->td_pflags & TDP_ALTSTACK) ? 598 #if defined(COMPAT_43) 599 ((td->td_sigstk.ss_size == 0) ? 600 (td->td_sigstk.ss_flags & SS_ONSTACK) : 601 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)) 602 #else 603 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size) 604 #endif 605 : 0); 606 } 607 608 static __inline int 609 sigprop(int sig) 610 { 611 612 if (sig > 0 && sig < NSIG) 613 return (sigproptbl[_SIG_IDX(sig)]); 614 return (0); 615 } 616 617 int 618 sig_ffs(sigset_t *set) 619 { 620 int i; 621 622 for (i = 0; i < _SIG_WORDS; i++) 623 if (set->__bits[i]) 624 return (ffs(set->__bits[i]) + (i * 32)); 625 return (0); 626 } 627 628 /* 629 * kern_sigaction 630 * sigaction 631 * freebsd4_sigaction 632 * osigaction 633 */ 634 int 635 kern_sigaction(td, sig, act, oact, flags) 636 struct thread *td; 637 register int sig; 638 struct sigaction *act, *oact; 639 int flags; 640 { 641 struct sigacts *ps; 642 struct proc *p = td->td_proc; 643 644 if (!_SIG_VALID(sig)) 645 return (EINVAL); 646 647 PROC_LOCK(p); 648 ps = p->p_sigacts; 649 mtx_lock(&ps->ps_mtx); 650 if (oact) { 651 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)]; 652 oact->sa_flags = 0; 653 if (SIGISMEMBER(ps->ps_sigonstack, sig)) 654 oact->sa_flags |= SA_ONSTACK; 655 if (!SIGISMEMBER(ps->ps_sigintr, sig)) 656 oact->sa_flags |= SA_RESTART; 657 if (SIGISMEMBER(ps->ps_sigreset, sig)) 658 oact->sa_flags |= SA_RESETHAND; 659 if (SIGISMEMBER(ps->ps_signodefer, sig)) 660 oact->sa_flags |= SA_NODEFER; 661 if (SIGISMEMBER(ps->ps_siginfo, sig)) { 662 oact->sa_flags |= SA_SIGINFO; 663 oact->sa_sigaction = 664 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)]; 665 } else 666 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)]; 667 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP) 668 oact->sa_flags |= SA_NOCLDSTOP; 669 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT) 670 oact->sa_flags |= SA_NOCLDWAIT; 671 } 672 if (act) { 673 if ((sig == SIGKILL || sig == SIGSTOP) && 674 act->sa_handler != SIG_DFL) { 675 mtx_unlock(&ps->ps_mtx); 676 PROC_UNLOCK(p); 677 return (EINVAL); 678 } 679 680 /* 681 * Change setting atomically. 682 */ 683 684 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask; 685 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]); 686 if (act->sa_flags & SA_SIGINFO) { 687 ps->ps_sigact[_SIG_IDX(sig)] = 688 (__sighandler_t *)act->sa_sigaction; 689 SIGADDSET(ps->ps_siginfo, sig); 690 } else { 691 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler; 692 SIGDELSET(ps->ps_siginfo, sig); 693 } 694 if (!(act->sa_flags & SA_RESTART)) 695 SIGADDSET(ps->ps_sigintr, sig); 696 else 697 SIGDELSET(ps->ps_sigintr, sig); 698 if (act->sa_flags & SA_ONSTACK) 699 SIGADDSET(ps->ps_sigonstack, sig); 700 else 701 SIGDELSET(ps->ps_sigonstack, sig); 702 if (act->sa_flags & SA_RESETHAND) 703 SIGADDSET(ps->ps_sigreset, sig); 704 else 705 SIGDELSET(ps->ps_sigreset, sig); 706 if (act->sa_flags & SA_NODEFER) 707 SIGADDSET(ps->ps_signodefer, sig); 708 else 709 SIGDELSET(ps->ps_signodefer, sig); 710 if (sig == SIGCHLD) { 711 if (act->sa_flags & SA_NOCLDSTOP) 712 ps->ps_flag |= PS_NOCLDSTOP; 713 else 714 ps->ps_flag &= ~PS_NOCLDSTOP; 715 if (act->sa_flags & SA_NOCLDWAIT) { 716 /* 717 * Paranoia: since SA_NOCLDWAIT is implemented 718 * by reparenting the dying child to PID 1 (and 719 * trust it to reap the zombie), PID 1 itself 720 * is forbidden to set SA_NOCLDWAIT. 721 */ 722 if (p->p_pid == 1) 723 ps->ps_flag &= ~PS_NOCLDWAIT; 724 else 725 ps->ps_flag |= PS_NOCLDWAIT; 726 } else 727 ps->ps_flag &= ~PS_NOCLDWAIT; 728 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 729 ps->ps_flag |= PS_CLDSIGIGN; 730 else 731 ps->ps_flag &= ~PS_CLDSIGIGN; 732 } 733 /* 734 * Set bit in ps_sigignore for signals that are set to SIG_IGN, 735 * and for signals set to SIG_DFL where the default is to 736 * ignore. However, don't put SIGCONT in ps_sigignore, as we 737 * have to restart the process. 738 */ 739 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 740 (sigprop(sig) & SA_IGNORE && 741 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) { 742 /* never to be seen again */ 743 sigqueue_delete_proc(p, sig); 744 if (sig != SIGCONT) 745 /* easier in psignal */ 746 SIGADDSET(ps->ps_sigignore, sig); 747 SIGDELSET(ps->ps_sigcatch, sig); 748 } else { 749 SIGDELSET(ps->ps_sigignore, sig); 750 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL) 751 SIGDELSET(ps->ps_sigcatch, sig); 752 else 753 SIGADDSET(ps->ps_sigcatch, sig); 754 } 755 #ifdef COMPAT_FREEBSD4 756 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 757 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 758 (flags & KSA_FREEBSD4) == 0) 759 SIGDELSET(ps->ps_freebsd4, sig); 760 else 761 SIGADDSET(ps->ps_freebsd4, sig); 762 #endif 763 #ifdef COMPAT_43 764 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 765 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 766 (flags & KSA_OSIGSET) == 0) 767 SIGDELSET(ps->ps_osigset, sig); 768 else 769 SIGADDSET(ps->ps_osigset, sig); 770 #endif 771 } 772 mtx_unlock(&ps->ps_mtx); 773 PROC_UNLOCK(p); 774 return (0); 775 } 776 777 #ifndef _SYS_SYSPROTO_H_ 778 struct sigaction_args { 779 int sig; 780 struct sigaction *act; 781 struct sigaction *oact; 782 }; 783 #endif 784 int 785 sys_sigaction(td, uap) 786 struct thread *td; 787 register struct sigaction_args *uap; 788 { 789 struct sigaction act, oact; 790 register struct sigaction *actp, *oactp; 791 int error; 792 793 actp = (uap->act != NULL) ? &act : NULL; 794 oactp = (uap->oact != NULL) ? &oact : NULL; 795 if (actp) { 796 error = copyin(uap->act, actp, sizeof(act)); 797 if (error) 798 return (error); 799 } 800 error = kern_sigaction(td, uap->sig, actp, oactp, 0); 801 if (oactp && !error) 802 error = copyout(oactp, uap->oact, sizeof(oact)); 803 return (error); 804 } 805 806 #ifdef COMPAT_FREEBSD4 807 #ifndef _SYS_SYSPROTO_H_ 808 struct freebsd4_sigaction_args { 809 int sig; 810 struct sigaction *act; 811 struct sigaction *oact; 812 }; 813 #endif 814 int 815 freebsd4_sigaction(td, uap) 816 struct thread *td; 817 register struct freebsd4_sigaction_args *uap; 818 { 819 struct sigaction act, oact; 820 register struct sigaction *actp, *oactp; 821 int error; 822 823 824 actp = (uap->act != NULL) ? &act : NULL; 825 oactp = (uap->oact != NULL) ? &oact : NULL; 826 if (actp) { 827 error = copyin(uap->act, actp, sizeof(act)); 828 if (error) 829 return (error); 830 } 831 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4); 832 if (oactp && !error) 833 error = copyout(oactp, uap->oact, sizeof(oact)); 834 return (error); 835 } 836 #endif /* COMAPT_FREEBSD4 */ 837 838 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 839 #ifndef _SYS_SYSPROTO_H_ 840 struct osigaction_args { 841 int signum; 842 struct osigaction *nsa; 843 struct osigaction *osa; 844 }; 845 #endif 846 int 847 osigaction(td, uap) 848 struct thread *td; 849 register struct osigaction_args *uap; 850 { 851 struct osigaction sa; 852 struct sigaction nsa, osa; 853 register struct sigaction *nsap, *osap; 854 int error; 855 856 if (uap->signum <= 0 || uap->signum >= ONSIG) 857 return (EINVAL); 858 859 nsap = (uap->nsa != NULL) ? &nsa : NULL; 860 osap = (uap->osa != NULL) ? &osa : NULL; 861 862 if (nsap) { 863 error = copyin(uap->nsa, &sa, sizeof(sa)); 864 if (error) 865 return (error); 866 nsap->sa_handler = sa.sa_handler; 867 nsap->sa_flags = sa.sa_flags; 868 OSIG2SIG(sa.sa_mask, nsap->sa_mask); 869 } 870 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 871 if (osap && !error) { 872 sa.sa_handler = osap->sa_handler; 873 sa.sa_flags = osap->sa_flags; 874 SIG2OSIG(osap->sa_mask, sa.sa_mask); 875 error = copyout(&sa, uap->osa, sizeof(sa)); 876 } 877 return (error); 878 } 879 880 #if !defined(__i386__) 881 /* Avoid replicating the same stub everywhere */ 882 int 883 osigreturn(td, uap) 884 struct thread *td; 885 struct osigreturn_args *uap; 886 { 887 888 return (nosys(td, (struct nosys_args *)uap)); 889 } 890 #endif 891 #endif /* COMPAT_43 */ 892 893 /* 894 * Initialize signal state for process 0; 895 * set to ignore signals that are ignored by default. 896 */ 897 void 898 siginit(p) 899 struct proc *p; 900 { 901 register int i; 902 struct sigacts *ps; 903 904 PROC_LOCK(p); 905 ps = p->p_sigacts; 906 mtx_lock(&ps->ps_mtx); 907 for (i = 1; i <= NSIG; i++) 908 if (sigprop(i) & SA_IGNORE && i != SIGCONT) 909 SIGADDSET(ps->ps_sigignore, i); 910 mtx_unlock(&ps->ps_mtx); 911 PROC_UNLOCK(p); 912 } 913 914 /* 915 * Reset signals for an exec of the specified process. 916 */ 917 void 918 execsigs(struct proc *p) 919 { 920 struct sigacts *ps; 921 int sig; 922 struct thread *td; 923 924 /* 925 * Reset caught signals. Held signals remain held 926 * through td_sigmask (unless they were caught, 927 * and are now ignored by default). 928 */ 929 PROC_LOCK_ASSERT(p, MA_OWNED); 930 td = FIRST_THREAD_IN_PROC(p); 931 ps = p->p_sigacts; 932 mtx_lock(&ps->ps_mtx); 933 while (SIGNOTEMPTY(ps->ps_sigcatch)) { 934 sig = sig_ffs(&ps->ps_sigcatch); 935 SIGDELSET(ps->ps_sigcatch, sig); 936 if (sigprop(sig) & SA_IGNORE) { 937 if (sig != SIGCONT) 938 SIGADDSET(ps->ps_sigignore, sig); 939 sigqueue_delete_proc(p, sig); 940 } 941 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 942 } 943 /* 944 * Reset stack state to the user stack. 945 * Clear set of signals caught on the signal stack. 946 */ 947 td->td_sigstk.ss_flags = SS_DISABLE; 948 td->td_sigstk.ss_size = 0; 949 td->td_sigstk.ss_sp = 0; 950 td->td_pflags &= ~TDP_ALTSTACK; 951 /* 952 * Reset no zombies if child dies flag as Solaris does. 953 */ 954 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN); 955 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 956 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL; 957 mtx_unlock(&ps->ps_mtx); 958 } 959 960 /* 961 * kern_sigprocmask() 962 * 963 * Manipulate signal mask. 964 */ 965 int 966 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset, 967 int flags) 968 { 969 sigset_t new_block, oset1; 970 struct proc *p; 971 int error; 972 973 p = td->td_proc; 974 if (!(flags & SIGPROCMASK_PROC_LOCKED)) 975 PROC_LOCK(p); 976 if (oset != NULL) 977 *oset = td->td_sigmask; 978 979 error = 0; 980 if (set != NULL) { 981 switch (how) { 982 case SIG_BLOCK: 983 SIG_CANTMASK(*set); 984 oset1 = td->td_sigmask; 985 SIGSETOR(td->td_sigmask, *set); 986 new_block = td->td_sigmask; 987 SIGSETNAND(new_block, oset1); 988 break; 989 case SIG_UNBLOCK: 990 SIGSETNAND(td->td_sigmask, *set); 991 signotify(td); 992 goto out; 993 case SIG_SETMASK: 994 SIG_CANTMASK(*set); 995 oset1 = td->td_sigmask; 996 if (flags & SIGPROCMASK_OLD) 997 SIGSETLO(td->td_sigmask, *set); 998 else 999 td->td_sigmask = *set; 1000 new_block = td->td_sigmask; 1001 SIGSETNAND(new_block, oset1); 1002 signotify(td); 1003 break; 1004 default: 1005 error = EINVAL; 1006 goto out; 1007 } 1008 1009 /* 1010 * The new_block set contains signals that were not previously 1011 * blocked, but are blocked now. 1012 * 1013 * In case we block any signal that was not previously blocked 1014 * for td, and process has the signal pending, try to schedule 1015 * signal delivery to some thread that does not block the 1016 * signal, possibly waking it up. 1017 */ 1018 if (p->p_numthreads != 1) 1019 reschedule_signals(p, new_block, flags); 1020 } 1021 1022 out: 1023 if (!(flags & SIGPROCMASK_PROC_LOCKED)) 1024 PROC_UNLOCK(p); 1025 return (error); 1026 } 1027 1028 #ifndef _SYS_SYSPROTO_H_ 1029 struct sigprocmask_args { 1030 int how; 1031 const sigset_t *set; 1032 sigset_t *oset; 1033 }; 1034 #endif 1035 int 1036 sys_sigprocmask(td, uap) 1037 register struct thread *td; 1038 struct sigprocmask_args *uap; 1039 { 1040 sigset_t set, oset; 1041 sigset_t *setp, *osetp; 1042 int error; 1043 1044 setp = (uap->set != NULL) ? &set : NULL; 1045 osetp = (uap->oset != NULL) ? &oset : NULL; 1046 if (setp) { 1047 error = copyin(uap->set, setp, sizeof(set)); 1048 if (error) 1049 return (error); 1050 } 1051 error = kern_sigprocmask(td, uap->how, setp, osetp, 0); 1052 if (osetp && !error) { 1053 error = copyout(osetp, uap->oset, sizeof(oset)); 1054 } 1055 return (error); 1056 } 1057 1058 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 1059 #ifndef _SYS_SYSPROTO_H_ 1060 struct osigprocmask_args { 1061 int how; 1062 osigset_t mask; 1063 }; 1064 #endif 1065 int 1066 osigprocmask(td, uap) 1067 register struct thread *td; 1068 struct osigprocmask_args *uap; 1069 { 1070 sigset_t set, oset; 1071 int error; 1072 1073 OSIG2SIG(uap->mask, set); 1074 error = kern_sigprocmask(td, uap->how, &set, &oset, 1); 1075 SIG2OSIG(oset, td->td_retval[0]); 1076 return (error); 1077 } 1078 #endif /* COMPAT_43 */ 1079 1080 int 1081 sys_sigwait(struct thread *td, struct sigwait_args *uap) 1082 { 1083 ksiginfo_t ksi; 1084 sigset_t set; 1085 int error; 1086 1087 error = copyin(uap->set, &set, sizeof(set)); 1088 if (error) { 1089 td->td_retval[0] = error; 1090 return (0); 1091 } 1092 1093 error = kern_sigtimedwait(td, set, &ksi, NULL); 1094 if (error) { 1095 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT) 1096 error = ERESTART; 1097 if (error == ERESTART) 1098 return (error); 1099 td->td_retval[0] = error; 1100 return (0); 1101 } 1102 1103 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo)); 1104 td->td_retval[0] = error; 1105 return (0); 1106 } 1107 1108 int 1109 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap) 1110 { 1111 struct timespec ts; 1112 struct timespec *timeout; 1113 sigset_t set; 1114 ksiginfo_t ksi; 1115 int error; 1116 1117 if (uap->timeout) { 1118 error = copyin(uap->timeout, &ts, sizeof(ts)); 1119 if (error) 1120 return (error); 1121 1122 timeout = &ts; 1123 } else 1124 timeout = NULL; 1125 1126 error = copyin(uap->set, &set, sizeof(set)); 1127 if (error) 1128 return (error); 1129 1130 error = kern_sigtimedwait(td, set, &ksi, timeout); 1131 if (error) 1132 return (error); 1133 1134 if (uap->info) 1135 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t)); 1136 1137 if (error == 0) 1138 td->td_retval[0] = ksi.ksi_signo; 1139 return (error); 1140 } 1141 1142 int 1143 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap) 1144 { 1145 ksiginfo_t ksi; 1146 sigset_t set; 1147 int error; 1148 1149 error = copyin(uap->set, &set, sizeof(set)); 1150 if (error) 1151 return (error); 1152 1153 error = kern_sigtimedwait(td, set, &ksi, NULL); 1154 if (error) 1155 return (error); 1156 1157 if (uap->info) 1158 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t)); 1159 1160 if (error == 0) 1161 td->td_retval[0] = ksi.ksi_signo; 1162 return (error); 1163 } 1164 1165 int 1166 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi, 1167 struct timespec *timeout) 1168 { 1169 struct sigacts *ps; 1170 sigset_t saved_mask, new_block; 1171 struct proc *p; 1172 int error, sig, timo, timevalid = 0; 1173 struct timespec rts, ets, ts; 1174 struct timeval tv; 1175 1176 p = td->td_proc; 1177 error = 0; 1178 ets.tv_sec = 0; 1179 ets.tv_nsec = 0; 1180 1181 if (timeout != NULL) { 1182 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) { 1183 timevalid = 1; 1184 getnanouptime(&rts); 1185 ets = rts; 1186 timespecadd(&ets, timeout); 1187 } 1188 } 1189 ksiginfo_init(ksi); 1190 /* Some signals can not be waited for. */ 1191 SIG_CANTMASK(waitset); 1192 ps = p->p_sigacts; 1193 PROC_LOCK(p); 1194 saved_mask = td->td_sigmask; 1195 SIGSETNAND(td->td_sigmask, waitset); 1196 for (;;) { 1197 mtx_lock(&ps->ps_mtx); 1198 sig = cursig(td); 1199 mtx_unlock(&ps->ps_mtx); 1200 if (sig != 0 && SIGISMEMBER(waitset, sig)) { 1201 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 || 1202 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) { 1203 error = 0; 1204 break; 1205 } 1206 } 1207 1208 if (error != 0) 1209 break; 1210 1211 /* 1212 * POSIX says this must be checked after looking for pending 1213 * signals. 1214 */ 1215 if (timeout != NULL) { 1216 if (!timevalid) { 1217 error = EINVAL; 1218 break; 1219 } 1220 getnanouptime(&rts); 1221 if (timespeccmp(&rts, &ets, >=)) { 1222 error = EAGAIN; 1223 break; 1224 } 1225 ts = ets; 1226 timespecsub(&ts, &rts); 1227 TIMESPEC_TO_TIMEVAL(&tv, &ts); 1228 timo = tvtohz(&tv); 1229 } else { 1230 timo = 0; 1231 } 1232 1233 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo); 1234 1235 if (timeout != NULL) { 1236 if (error == ERESTART) { 1237 /* Timeout can not be restarted. */ 1238 error = EINTR; 1239 } else if (error == EAGAIN) { 1240 /* We will calculate timeout by ourself. */ 1241 error = 0; 1242 } 1243 } 1244 } 1245 1246 new_block = saved_mask; 1247 SIGSETNAND(new_block, td->td_sigmask); 1248 td->td_sigmask = saved_mask; 1249 /* 1250 * Fewer signals can be delivered to us, reschedule signal 1251 * notification. 1252 */ 1253 if (p->p_numthreads != 1) 1254 reschedule_signals(p, new_block, 0); 1255 1256 if (error == 0) { 1257 SDT_PROBE(proc, kernel, , signal_clear, sig, ksi, 0, 0, 0); 1258 1259 if (ksi->ksi_code == SI_TIMER) 1260 itimer_accept(p, ksi->ksi_timerid, ksi); 1261 1262 #ifdef KTRACE 1263 if (KTRPOINT(td, KTR_PSIG)) { 1264 sig_t action; 1265 1266 mtx_lock(&ps->ps_mtx); 1267 action = ps->ps_sigact[_SIG_IDX(sig)]; 1268 mtx_unlock(&ps->ps_mtx); 1269 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code); 1270 } 1271 #endif 1272 if (sig == SIGKILL) 1273 sigexit(td, sig); 1274 } 1275 PROC_UNLOCK(p); 1276 return (error); 1277 } 1278 1279 #ifndef _SYS_SYSPROTO_H_ 1280 struct sigpending_args { 1281 sigset_t *set; 1282 }; 1283 #endif 1284 int 1285 sys_sigpending(td, uap) 1286 struct thread *td; 1287 struct sigpending_args *uap; 1288 { 1289 struct proc *p = td->td_proc; 1290 sigset_t pending; 1291 1292 PROC_LOCK(p); 1293 pending = p->p_sigqueue.sq_signals; 1294 SIGSETOR(pending, td->td_sigqueue.sq_signals); 1295 PROC_UNLOCK(p); 1296 return (copyout(&pending, uap->set, sizeof(sigset_t))); 1297 } 1298 1299 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 1300 #ifndef _SYS_SYSPROTO_H_ 1301 struct osigpending_args { 1302 int dummy; 1303 }; 1304 #endif 1305 int 1306 osigpending(td, uap) 1307 struct thread *td; 1308 struct osigpending_args *uap; 1309 { 1310 struct proc *p = td->td_proc; 1311 sigset_t pending; 1312 1313 PROC_LOCK(p); 1314 pending = p->p_sigqueue.sq_signals; 1315 SIGSETOR(pending, td->td_sigqueue.sq_signals); 1316 PROC_UNLOCK(p); 1317 SIG2OSIG(pending, td->td_retval[0]); 1318 return (0); 1319 } 1320 #endif /* COMPAT_43 */ 1321 1322 #if defined(COMPAT_43) 1323 /* 1324 * Generalized interface signal handler, 4.3-compatible. 1325 */ 1326 #ifndef _SYS_SYSPROTO_H_ 1327 struct osigvec_args { 1328 int signum; 1329 struct sigvec *nsv; 1330 struct sigvec *osv; 1331 }; 1332 #endif 1333 /* ARGSUSED */ 1334 int 1335 osigvec(td, uap) 1336 struct thread *td; 1337 register struct osigvec_args *uap; 1338 { 1339 struct sigvec vec; 1340 struct sigaction nsa, osa; 1341 register struct sigaction *nsap, *osap; 1342 int error; 1343 1344 if (uap->signum <= 0 || uap->signum >= ONSIG) 1345 return (EINVAL); 1346 nsap = (uap->nsv != NULL) ? &nsa : NULL; 1347 osap = (uap->osv != NULL) ? &osa : NULL; 1348 if (nsap) { 1349 error = copyin(uap->nsv, &vec, sizeof(vec)); 1350 if (error) 1351 return (error); 1352 nsap->sa_handler = vec.sv_handler; 1353 OSIG2SIG(vec.sv_mask, nsap->sa_mask); 1354 nsap->sa_flags = vec.sv_flags; 1355 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */ 1356 } 1357 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 1358 if (osap && !error) { 1359 vec.sv_handler = osap->sa_handler; 1360 SIG2OSIG(osap->sa_mask, vec.sv_mask); 1361 vec.sv_flags = osap->sa_flags; 1362 vec.sv_flags &= ~SA_NOCLDWAIT; 1363 vec.sv_flags ^= SA_RESTART; 1364 error = copyout(&vec, uap->osv, sizeof(vec)); 1365 } 1366 return (error); 1367 } 1368 1369 #ifndef _SYS_SYSPROTO_H_ 1370 struct osigblock_args { 1371 int mask; 1372 }; 1373 #endif 1374 int 1375 osigblock(td, uap) 1376 register struct thread *td; 1377 struct osigblock_args *uap; 1378 { 1379 sigset_t set, oset; 1380 1381 OSIG2SIG(uap->mask, set); 1382 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0); 1383 SIG2OSIG(oset, td->td_retval[0]); 1384 return (0); 1385 } 1386 1387 #ifndef _SYS_SYSPROTO_H_ 1388 struct osigsetmask_args { 1389 int mask; 1390 }; 1391 #endif 1392 int 1393 osigsetmask(td, uap) 1394 struct thread *td; 1395 struct osigsetmask_args *uap; 1396 { 1397 sigset_t set, oset; 1398 1399 OSIG2SIG(uap->mask, set); 1400 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0); 1401 SIG2OSIG(oset, td->td_retval[0]); 1402 return (0); 1403 } 1404 #endif /* COMPAT_43 */ 1405 1406 /* 1407 * Suspend calling thread until signal, providing mask to be set in the 1408 * meantime. 1409 */ 1410 #ifndef _SYS_SYSPROTO_H_ 1411 struct sigsuspend_args { 1412 const sigset_t *sigmask; 1413 }; 1414 #endif 1415 /* ARGSUSED */ 1416 int 1417 sys_sigsuspend(td, uap) 1418 struct thread *td; 1419 struct sigsuspend_args *uap; 1420 { 1421 sigset_t mask; 1422 int error; 1423 1424 error = copyin(uap->sigmask, &mask, sizeof(mask)); 1425 if (error) 1426 return (error); 1427 return (kern_sigsuspend(td, mask)); 1428 } 1429 1430 int 1431 kern_sigsuspend(struct thread *td, sigset_t mask) 1432 { 1433 struct proc *p = td->td_proc; 1434 int has_sig, sig; 1435 1436 /* 1437 * When returning from sigsuspend, we want 1438 * the old mask to be restored after the 1439 * signal handler has finished. Thus, we 1440 * save it here and mark the sigacts structure 1441 * to indicate this. 1442 */ 1443 PROC_LOCK(p); 1444 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask, 1445 SIGPROCMASK_PROC_LOCKED); 1446 td->td_pflags |= TDP_OLDMASK; 1447 1448 /* 1449 * Process signals now. Otherwise, we can get spurious wakeup 1450 * due to signal entered process queue, but delivered to other 1451 * thread. But sigsuspend should return only on signal 1452 * delivery. 1453 */ 1454 (p->p_sysent->sv_set_syscall_retval)(td, EINTR); 1455 for (has_sig = 0; !has_sig;) { 1456 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 1457 0) == 0) 1458 /* void */; 1459 thread_suspend_check(0); 1460 mtx_lock(&p->p_sigacts->ps_mtx); 1461 while ((sig = cursig(td)) != 0) 1462 has_sig += postsig(sig); 1463 mtx_unlock(&p->p_sigacts->ps_mtx); 1464 } 1465 PROC_UNLOCK(p); 1466 td->td_errno = EINTR; 1467 td->td_pflags |= TDP_NERRNO; 1468 return (EJUSTRETURN); 1469 } 1470 1471 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 1472 /* 1473 * Compatibility sigsuspend call for old binaries. Note nonstandard calling 1474 * convention: libc stub passes mask, not pointer, to save a copyin. 1475 */ 1476 #ifndef _SYS_SYSPROTO_H_ 1477 struct osigsuspend_args { 1478 osigset_t mask; 1479 }; 1480 #endif 1481 /* ARGSUSED */ 1482 int 1483 osigsuspend(td, uap) 1484 struct thread *td; 1485 struct osigsuspend_args *uap; 1486 { 1487 sigset_t mask; 1488 1489 OSIG2SIG(uap->mask, mask); 1490 return (kern_sigsuspend(td, mask)); 1491 } 1492 #endif /* COMPAT_43 */ 1493 1494 #if defined(COMPAT_43) 1495 #ifndef _SYS_SYSPROTO_H_ 1496 struct osigstack_args { 1497 struct sigstack *nss; 1498 struct sigstack *oss; 1499 }; 1500 #endif 1501 /* ARGSUSED */ 1502 int 1503 osigstack(td, uap) 1504 struct thread *td; 1505 register struct osigstack_args *uap; 1506 { 1507 struct sigstack nss, oss; 1508 int error = 0; 1509 1510 if (uap->nss != NULL) { 1511 error = copyin(uap->nss, &nss, sizeof(nss)); 1512 if (error) 1513 return (error); 1514 } 1515 oss.ss_sp = td->td_sigstk.ss_sp; 1516 oss.ss_onstack = sigonstack(cpu_getstack(td)); 1517 if (uap->nss != NULL) { 1518 td->td_sigstk.ss_sp = nss.ss_sp; 1519 td->td_sigstk.ss_size = 0; 1520 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK; 1521 td->td_pflags |= TDP_ALTSTACK; 1522 } 1523 if (uap->oss != NULL) 1524 error = copyout(&oss, uap->oss, sizeof(oss)); 1525 1526 return (error); 1527 } 1528 #endif /* COMPAT_43 */ 1529 1530 #ifndef _SYS_SYSPROTO_H_ 1531 struct sigaltstack_args { 1532 stack_t *ss; 1533 stack_t *oss; 1534 }; 1535 #endif 1536 /* ARGSUSED */ 1537 int 1538 sys_sigaltstack(td, uap) 1539 struct thread *td; 1540 register struct sigaltstack_args *uap; 1541 { 1542 stack_t ss, oss; 1543 int error; 1544 1545 if (uap->ss != NULL) { 1546 error = copyin(uap->ss, &ss, sizeof(ss)); 1547 if (error) 1548 return (error); 1549 } 1550 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL, 1551 (uap->oss != NULL) ? &oss : NULL); 1552 if (error) 1553 return (error); 1554 if (uap->oss != NULL) 1555 error = copyout(&oss, uap->oss, sizeof(stack_t)); 1556 return (error); 1557 } 1558 1559 int 1560 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss) 1561 { 1562 struct proc *p = td->td_proc; 1563 int oonstack; 1564 1565 oonstack = sigonstack(cpu_getstack(td)); 1566 1567 if (oss != NULL) { 1568 *oss = td->td_sigstk; 1569 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK) 1570 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; 1571 } 1572 1573 if (ss != NULL) { 1574 if (oonstack) 1575 return (EPERM); 1576 if ((ss->ss_flags & ~SS_DISABLE) != 0) 1577 return (EINVAL); 1578 if (!(ss->ss_flags & SS_DISABLE)) { 1579 if (ss->ss_size < p->p_sysent->sv_minsigstksz) 1580 return (ENOMEM); 1581 1582 td->td_sigstk = *ss; 1583 td->td_pflags |= TDP_ALTSTACK; 1584 } else { 1585 td->td_pflags &= ~TDP_ALTSTACK; 1586 } 1587 } 1588 return (0); 1589 } 1590 1591 /* 1592 * Common code for kill process group/broadcast kill. 1593 * cp is calling process. 1594 */ 1595 static int 1596 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi) 1597 { 1598 struct proc *p; 1599 struct pgrp *pgrp; 1600 int err; 1601 int ret; 1602 1603 ret = ESRCH; 1604 if (all) { 1605 /* 1606 * broadcast 1607 */ 1608 sx_slock(&allproc_lock); 1609 FOREACH_PROC_IN_SYSTEM(p) { 1610 PROC_LOCK(p); 1611 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || 1612 p == td->td_proc || p->p_state == PRS_NEW) { 1613 PROC_UNLOCK(p); 1614 continue; 1615 } 1616 err = p_cansignal(td, p, sig); 1617 if (err == 0) { 1618 if (sig) 1619 pksignal(p, sig, ksi); 1620 ret = err; 1621 } 1622 else if (ret == ESRCH) 1623 ret = err; 1624 PROC_UNLOCK(p); 1625 } 1626 sx_sunlock(&allproc_lock); 1627 } else { 1628 sx_slock(&proctree_lock); 1629 if (pgid == 0) { 1630 /* 1631 * zero pgid means send to my process group. 1632 */ 1633 pgrp = td->td_proc->p_pgrp; 1634 PGRP_LOCK(pgrp); 1635 } else { 1636 pgrp = pgfind(pgid); 1637 if (pgrp == NULL) { 1638 sx_sunlock(&proctree_lock); 1639 return (ESRCH); 1640 } 1641 } 1642 sx_sunlock(&proctree_lock); 1643 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1644 PROC_LOCK(p); 1645 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || 1646 p->p_state == PRS_NEW) { 1647 PROC_UNLOCK(p); 1648 continue; 1649 } 1650 err = p_cansignal(td, p, sig); 1651 if (err == 0) { 1652 if (sig) 1653 pksignal(p, sig, ksi); 1654 ret = err; 1655 } 1656 else if (ret == ESRCH) 1657 ret = err; 1658 PROC_UNLOCK(p); 1659 } 1660 PGRP_UNLOCK(pgrp); 1661 } 1662 return (ret); 1663 } 1664 1665 #ifndef _SYS_SYSPROTO_H_ 1666 struct kill_args { 1667 int pid; 1668 int signum; 1669 }; 1670 #endif 1671 /* ARGSUSED */ 1672 int 1673 sys_kill(struct thread *td, struct kill_args *uap) 1674 { 1675 ksiginfo_t ksi; 1676 struct proc *p; 1677 int error; 1678 1679 /* 1680 * A process in capability mode can send signals only to himself. 1681 * The main rationale behind this is that abort(3) is implemented as 1682 * kill(getpid(), SIGABRT). 1683 */ 1684 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid) 1685 return (ECAPMODE); 1686 1687 AUDIT_ARG_SIGNUM(uap->signum); 1688 AUDIT_ARG_PID(uap->pid); 1689 if ((u_int)uap->signum > _SIG_MAXSIG) 1690 return (EINVAL); 1691 1692 ksiginfo_init(&ksi); 1693 ksi.ksi_signo = uap->signum; 1694 ksi.ksi_code = SI_USER; 1695 ksi.ksi_pid = td->td_proc->p_pid; 1696 ksi.ksi_uid = td->td_ucred->cr_ruid; 1697 1698 if (uap->pid > 0) { 1699 /* kill single process */ 1700 if ((p = pfind(uap->pid)) == NULL) { 1701 if ((p = zpfind(uap->pid)) == NULL) 1702 return (ESRCH); 1703 } 1704 AUDIT_ARG_PROCESS(p); 1705 error = p_cansignal(td, p, uap->signum); 1706 if (error == 0 && uap->signum) 1707 pksignal(p, uap->signum, &ksi); 1708 PROC_UNLOCK(p); 1709 return (error); 1710 } 1711 switch (uap->pid) { 1712 case -1: /* broadcast signal */ 1713 return (killpg1(td, uap->signum, 0, 1, &ksi)); 1714 case 0: /* signal own process group */ 1715 return (killpg1(td, uap->signum, 0, 0, &ksi)); 1716 default: /* negative explicit process group */ 1717 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi)); 1718 } 1719 /* NOTREACHED */ 1720 } 1721 1722 int 1723 sys_pdkill(td, uap) 1724 struct thread *td; 1725 struct pdkill_args *uap; 1726 { 1727 #ifdef PROCDESC 1728 struct proc *p; 1729 int error; 1730 1731 AUDIT_ARG_SIGNUM(uap->signum); 1732 AUDIT_ARG_FD(uap->fd); 1733 if ((u_int)uap->signum > _SIG_MAXSIG) 1734 return (EINVAL); 1735 1736 error = procdesc_find(td, uap->fd, CAP_PDKILL, &p); 1737 if (error) 1738 return (error); 1739 AUDIT_ARG_PROCESS(p); 1740 error = p_cansignal(td, p, uap->signum); 1741 if (error == 0 && uap->signum) 1742 kern_psignal(p, uap->signum); 1743 PROC_UNLOCK(p); 1744 return (error); 1745 #else 1746 return (ENOSYS); 1747 #endif 1748 } 1749 1750 #if defined(COMPAT_43) 1751 #ifndef _SYS_SYSPROTO_H_ 1752 struct okillpg_args { 1753 int pgid; 1754 int signum; 1755 }; 1756 #endif 1757 /* ARGSUSED */ 1758 int 1759 okillpg(struct thread *td, struct okillpg_args *uap) 1760 { 1761 ksiginfo_t ksi; 1762 1763 AUDIT_ARG_SIGNUM(uap->signum); 1764 AUDIT_ARG_PID(uap->pgid); 1765 if ((u_int)uap->signum > _SIG_MAXSIG) 1766 return (EINVAL); 1767 1768 ksiginfo_init(&ksi); 1769 ksi.ksi_signo = uap->signum; 1770 ksi.ksi_code = SI_USER; 1771 ksi.ksi_pid = td->td_proc->p_pid; 1772 ksi.ksi_uid = td->td_ucred->cr_ruid; 1773 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi)); 1774 } 1775 #endif /* COMPAT_43 */ 1776 1777 #ifndef _SYS_SYSPROTO_H_ 1778 struct sigqueue_args { 1779 pid_t pid; 1780 int signum; 1781 /* union sigval */ void *value; 1782 }; 1783 #endif 1784 int 1785 sys_sigqueue(struct thread *td, struct sigqueue_args *uap) 1786 { 1787 ksiginfo_t ksi; 1788 struct proc *p; 1789 int error; 1790 1791 if ((u_int)uap->signum > _SIG_MAXSIG) 1792 return (EINVAL); 1793 1794 /* 1795 * Specification says sigqueue can only send signal to 1796 * single process. 1797 */ 1798 if (uap->pid <= 0) 1799 return (EINVAL); 1800 1801 if ((p = pfind(uap->pid)) == NULL) { 1802 if ((p = zpfind(uap->pid)) == NULL) 1803 return (ESRCH); 1804 } 1805 error = p_cansignal(td, p, uap->signum); 1806 if (error == 0 && uap->signum != 0) { 1807 ksiginfo_init(&ksi); 1808 ksi.ksi_flags = KSI_SIGQ; 1809 ksi.ksi_signo = uap->signum; 1810 ksi.ksi_code = SI_QUEUE; 1811 ksi.ksi_pid = td->td_proc->p_pid; 1812 ksi.ksi_uid = td->td_ucred->cr_ruid; 1813 ksi.ksi_value.sival_ptr = uap->value; 1814 error = pksignal(p, ksi.ksi_signo, &ksi); 1815 } 1816 PROC_UNLOCK(p); 1817 return (error); 1818 } 1819 1820 /* 1821 * Send a signal to a process group. 1822 */ 1823 void 1824 gsignal(int pgid, int sig, ksiginfo_t *ksi) 1825 { 1826 struct pgrp *pgrp; 1827 1828 if (pgid != 0) { 1829 sx_slock(&proctree_lock); 1830 pgrp = pgfind(pgid); 1831 sx_sunlock(&proctree_lock); 1832 if (pgrp != NULL) { 1833 pgsignal(pgrp, sig, 0, ksi); 1834 PGRP_UNLOCK(pgrp); 1835 } 1836 } 1837 } 1838 1839 /* 1840 * Send a signal to a process group. If checktty is 1, 1841 * limit to members which have a controlling terminal. 1842 */ 1843 void 1844 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi) 1845 { 1846 struct proc *p; 1847 1848 if (pgrp) { 1849 PGRP_LOCK_ASSERT(pgrp, MA_OWNED); 1850 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1851 PROC_LOCK(p); 1852 if (p->p_state == PRS_NORMAL && 1853 (checkctty == 0 || p->p_flag & P_CONTROLT)) 1854 pksignal(p, sig, ksi); 1855 PROC_UNLOCK(p); 1856 } 1857 } 1858 } 1859 1860 /* 1861 * Send a signal caused by a trap to the current thread. If it will be 1862 * caught immediately, deliver it with correct code. Otherwise, post it 1863 * normally. 1864 */ 1865 void 1866 trapsignal(struct thread *td, ksiginfo_t *ksi) 1867 { 1868 struct sigacts *ps; 1869 sigset_t mask; 1870 struct proc *p; 1871 int sig; 1872 int code; 1873 1874 p = td->td_proc; 1875 sig = ksi->ksi_signo; 1876 code = ksi->ksi_code; 1877 KASSERT(_SIG_VALID(sig), ("invalid signal")); 1878 1879 PROC_LOCK(p); 1880 ps = p->p_sigacts; 1881 mtx_lock(&ps->ps_mtx); 1882 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) && 1883 !SIGISMEMBER(td->td_sigmask, sig)) { 1884 td->td_ru.ru_nsignals++; 1885 #ifdef KTRACE 1886 if (KTRPOINT(curthread, KTR_PSIG)) 1887 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)], 1888 &td->td_sigmask, code); 1889 #endif 1890 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)], 1891 ksi, &td->td_sigmask); 1892 mask = ps->ps_catchmask[_SIG_IDX(sig)]; 1893 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 1894 SIGADDSET(mask, sig); 1895 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL, 1896 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED); 1897 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 1898 /* 1899 * See kern_sigaction() for origin of this code. 1900 */ 1901 SIGDELSET(ps->ps_sigcatch, sig); 1902 if (sig != SIGCONT && 1903 sigprop(sig) & SA_IGNORE) 1904 SIGADDSET(ps->ps_sigignore, sig); 1905 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 1906 } 1907 mtx_unlock(&ps->ps_mtx); 1908 } else { 1909 /* 1910 * Avoid a possible infinite loop if the thread 1911 * masking the signal or process is ignoring the 1912 * signal. 1913 */ 1914 if (kern_forcesigexit && 1915 (SIGISMEMBER(td->td_sigmask, sig) || 1916 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) { 1917 SIGDELSET(td->td_sigmask, sig); 1918 SIGDELSET(ps->ps_sigcatch, sig); 1919 SIGDELSET(ps->ps_sigignore, sig); 1920 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 1921 } 1922 mtx_unlock(&ps->ps_mtx); 1923 p->p_code = code; /* XXX for core dump/debugger */ 1924 p->p_sig = sig; /* XXX to verify code */ 1925 tdsendsignal(p, td, sig, ksi); 1926 } 1927 PROC_UNLOCK(p); 1928 } 1929 1930 static struct thread * 1931 sigtd(struct proc *p, int sig, int prop) 1932 { 1933 struct thread *td, *signal_td; 1934 1935 PROC_LOCK_ASSERT(p, MA_OWNED); 1936 1937 /* 1938 * Check if current thread can handle the signal without 1939 * switching context to another thread. 1940 */ 1941 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig)) 1942 return (curthread); 1943 signal_td = NULL; 1944 FOREACH_THREAD_IN_PROC(p, td) { 1945 if (!SIGISMEMBER(td->td_sigmask, sig)) { 1946 signal_td = td; 1947 break; 1948 } 1949 } 1950 if (signal_td == NULL) 1951 signal_td = FIRST_THREAD_IN_PROC(p); 1952 return (signal_td); 1953 } 1954 1955 /* 1956 * Send the signal to the process. If the signal has an action, the action 1957 * is usually performed by the target process rather than the caller; we add 1958 * the signal to the set of pending signals for the process. 1959 * 1960 * Exceptions: 1961 * o When a stop signal is sent to a sleeping process that takes the 1962 * default action, the process is stopped without awakening it. 1963 * o SIGCONT restarts stopped processes (or puts them back to sleep) 1964 * regardless of the signal action (eg, blocked or ignored). 1965 * 1966 * Other ignored signals are discarded immediately. 1967 * 1968 * NB: This function may be entered from the debugger via the "kill" DDB 1969 * command. There is little that can be done to mitigate the possibly messy 1970 * side effects of this unwise possibility. 1971 */ 1972 void 1973 kern_psignal(struct proc *p, int sig) 1974 { 1975 ksiginfo_t ksi; 1976 1977 ksiginfo_init(&ksi); 1978 ksi.ksi_signo = sig; 1979 ksi.ksi_code = SI_KERNEL; 1980 (void) tdsendsignal(p, NULL, sig, &ksi); 1981 } 1982 1983 int 1984 pksignal(struct proc *p, int sig, ksiginfo_t *ksi) 1985 { 1986 1987 return (tdsendsignal(p, NULL, sig, ksi)); 1988 } 1989 1990 /* Utility function for finding a thread to send signal event to. */ 1991 int 1992 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd) 1993 { 1994 struct thread *td; 1995 1996 if (sigev->sigev_notify == SIGEV_THREAD_ID) { 1997 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid); 1998 if (td == NULL) 1999 return (ESRCH); 2000 *ttd = td; 2001 } else { 2002 *ttd = NULL; 2003 PROC_LOCK(p); 2004 } 2005 return (0); 2006 } 2007 2008 void 2009 tdsignal(struct thread *td, int sig) 2010 { 2011 ksiginfo_t ksi; 2012 2013 ksiginfo_init(&ksi); 2014 ksi.ksi_signo = sig; 2015 ksi.ksi_code = SI_KERNEL; 2016 (void) tdsendsignal(td->td_proc, td, sig, &ksi); 2017 } 2018 2019 void 2020 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi) 2021 { 2022 2023 (void) tdsendsignal(td->td_proc, td, sig, ksi); 2024 } 2025 2026 int 2027 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi) 2028 { 2029 sig_t action; 2030 sigqueue_t *sigqueue; 2031 int prop; 2032 struct sigacts *ps; 2033 int intrval; 2034 int ret = 0; 2035 int wakeup_swapper; 2036 2037 MPASS(td == NULL || p == td->td_proc); 2038 PROC_LOCK_ASSERT(p, MA_OWNED); 2039 2040 if (!_SIG_VALID(sig)) 2041 panic("%s(): invalid signal %d", __func__, sig); 2042 2043 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__)); 2044 2045 /* 2046 * IEEE Std 1003.1-2001: return success when killing a zombie. 2047 */ 2048 if (p->p_state == PRS_ZOMBIE) { 2049 if (ksi && (ksi->ksi_flags & KSI_INS)) 2050 ksiginfo_tryfree(ksi); 2051 return (ret); 2052 } 2053 2054 ps = p->p_sigacts; 2055 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig); 2056 prop = sigprop(sig); 2057 2058 if (td == NULL) { 2059 td = sigtd(p, sig, prop); 2060 sigqueue = &p->p_sigqueue; 2061 } else 2062 sigqueue = &td->td_sigqueue; 2063 2064 SDT_PROBE(proc, kernel, , signal_send, td, p, sig, 0, 0 ); 2065 2066 /* 2067 * If the signal is being ignored, 2068 * then we forget about it immediately. 2069 * (Note: we don't set SIGCONT in ps_sigignore, 2070 * and if it is set to SIG_IGN, 2071 * action will be SIG_DFL here.) 2072 */ 2073 mtx_lock(&ps->ps_mtx); 2074 if (SIGISMEMBER(ps->ps_sigignore, sig)) { 2075 SDT_PROBE(proc, kernel, , signal_discard, td, p, sig, 0, 0 ); 2076 2077 mtx_unlock(&ps->ps_mtx); 2078 if (ksi && (ksi->ksi_flags & KSI_INS)) 2079 ksiginfo_tryfree(ksi); 2080 return (ret); 2081 } 2082 if (SIGISMEMBER(td->td_sigmask, sig)) 2083 action = SIG_HOLD; 2084 else if (SIGISMEMBER(ps->ps_sigcatch, sig)) 2085 action = SIG_CATCH; 2086 else 2087 action = SIG_DFL; 2088 if (SIGISMEMBER(ps->ps_sigintr, sig)) 2089 intrval = EINTR; 2090 else 2091 intrval = ERESTART; 2092 mtx_unlock(&ps->ps_mtx); 2093 2094 if (prop & SA_CONT) 2095 sigqueue_delete_stopmask_proc(p); 2096 else if (prop & SA_STOP) { 2097 /* 2098 * If sending a tty stop signal to a member of an orphaned 2099 * process group, discard the signal here if the action 2100 * is default; don't stop the process below if sleeping, 2101 * and don't clear any pending SIGCONT. 2102 */ 2103 if ((prop & SA_TTYSTOP) && 2104 (p->p_pgrp->pg_jobc == 0) && 2105 (action == SIG_DFL)) { 2106 if (ksi && (ksi->ksi_flags & KSI_INS)) 2107 ksiginfo_tryfree(ksi); 2108 return (ret); 2109 } 2110 sigqueue_delete_proc(p, SIGCONT); 2111 if (p->p_flag & P_CONTINUED) { 2112 p->p_flag &= ~P_CONTINUED; 2113 PROC_LOCK(p->p_pptr); 2114 sigqueue_take(p->p_ksi); 2115 PROC_UNLOCK(p->p_pptr); 2116 } 2117 } 2118 2119 ret = sigqueue_add(sigqueue, sig, ksi); 2120 if (ret != 0) 2121 return (ret); 2122 signotify(td); 2123 /* 2124 * Defer further processing for signals which are held, 2125 * except that stopped processes must be continued by SIGCONT. 2126 */ 2127 if (action == SIG_HOLD && 2128 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG))) 2129 return (ret); 2130 /* 2131 * SIGKILL: Remove procfs STOPEVENTs. 2132 */ 2133 if (sig == SIGKILL) { 2134 /* from procfs_ioctl.c: PIOCBIC */ 2135 p->p_stops = 0; 2136 /* from procfs_ioctl.c: PIOCCONT */ 2137 p->p_step = 0; 2138 wakeup(&p->p_step); 2139 } 2140 /* 2141 * Some signals have a process-wide effect and a per-thread 2142 * component. Most processing occurs when the process next 2143 * tries to cross the user boundary, however there are some 2144 * times when processing needs to be done immediately, such as 2145 * waking up threads so that they can cross the user boundary. 2146 * We try to do the per-process part here. 2147 */ 2148 if (P_SHOULDSTOP(p)) { 2149 KASSERT(!(p->p_flag & P_WEXIT), 2150 ("signal to stopped but exiting process")); 2151 if (sig == SIGKILL) { 2152 /* 2153 * If traced process is already stopped, 2154 * then no further action is necessary. 2155 */ 2156 if (p->p_flag & P_TRACED) 2157 goto out; 2158 /* 2159 * SIGKILL sets process running. 2160 * It will die elsewhere. 2161 * All threads must be restarted. 2162 */ 2163 p->p_flag &= ~P_STOPPED_SIG; 2164 goto runfast; 2165 } 2166 2167 if (prop & SA_CONT) { 2168 /* 2169 * If traced process is already stopped, 2170 * then no further action is necessary. 2171 */ 2172 if (p->p_flag & P_TRACED) 2173 goto out; 2174 /* 2175 * If SIGCONT is default (or ignored), we continue the 2176 * process but don't leave the signal in sigqueue as 2177 * it has no further action. If SIGCONT is held, we 2178 * continue the process and leave the signal in 2179 * sigqueue. If the process catches SIGCONT, let it 2180 * handle the signal itself. If it isn't waiting on 2181 * an event, it goes back to run state. 2182 * Otherwise, process goes back to sleep state. 2183 */ 2184 p->p_flag &= ~P_STOPPED_SIG; 2185 PROC_SLOCK(p); 2186 if (p->p_numthreads == p->p_suspcount) { 2187 PROC_SUNLOCK(p); 2188 p->p_flag |= P_CONTINUED; 2189 p->p_xstat = SIGCONT; 2190 PROC_LOCK(p->p_pptr); 2191 childproc_continued(p); 2192 PROC_UNLOCK(p->p_pptr); 2193 PROC_SLOCK(p); 2194 } 2195 if (action == SIG_DFL) { 2196 thread_unsuspend(p); 2197 PROC_SUNLOCK(p); 2198 sigqueue_delete(sigqueue, sig); 2199 goto out; 2200 } 2201 if (action == SIG_CATCH) { 2202 /* 2203 * The process wants to catch it so it needs 2204 * to run at least one thread, but which one? 2205 */ 2206 PROC_SUNLOCK(p); 2207 goto runfast; 2208 } 2209 /* 2210 * The signal is not ignored or caught. 2211 */ 2212 thread_unsuspend(p); 2213 PROC_SUNLOCK(p); 2214 goto out; 2215 } 2216 2217 if (prop & SA_STOP) { 2218 /* 2219 * If traced process is already stopped, 2220 * then no further action is necessary. 2221 */ 2222 if (p->p_flag & P_TRACED) 2223 goto out; 2224 /* 2225 * Already stopped, don't need to stop again 2226 * (If we did the shell could get confused). 2227 * Just make sure the signal STOP bit set. 2228 */ 2229 p->p_flag |= P_STOPPED_SIG; 2230 sigqueue_delete(sigqueue, sig); 2231 goto out; 2232 } 2233 2234 /* 2235 * All other kinds of signals: 2236 * If a thread is sleeping interruptibly, simulate a 2237 * wakeup so that when it is continued it will be made 2238 * runnable and can look at the signal. However, don't make 2239 * the PROCESS runnable, leave it stopped. 2240 * It may run a bit until it hits a thread_suspend_check(). 2241 */ 2242 wakeup_swapper = 0; 2243 PROC_SLOCK(p); 2244 thread_lock(td); 2245 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR)) 2246 wakeup_swapper = sleepq_abort(td, intrval); 2247 thread_unlock(td); 2248 PROC_SUNLOCK(p); 2249 if (wakeup_swapper) 2250 kick_proc0(); 2251 goto out; 2252 /* 2253 * Mutexes are short lived. Threads waiting on them will 2254 * hit thread_suspend_check() soon. 2255 */ 2256 } else if (p->p_state == PRS_NORMAL) { 2257 if (p->p_flag & P_TRACED || action == SIG_CATCH) { 2258 tdsigwakeup(td, sig, action, intrval); 2259 goto out; 2260 } 2261 2262 MPASS(action == SIG_DFL); 2263 2264 if (prop & SA_STOP) { 2265 if (p->p_flag & (P_PPWAIT|P_WEXIT)) 2266 goto out; 2267 p->p_flag |= P_STOPPED_SIG; 2268 p->p_xstat = sig; 2269 PROC_SLOCK(p); 2270 sig_suspend_threads(td, p, 1); 2271 if (p->p_numthreads == p->p_suspcount) { 2272 /* 2273 * only thread sending signal to another 2274 * process can reach here, if thread is sending 2275 * signal to its process, because thread does 2276 * not suspend itself here, p_numthreads 2277 * should never be equal to p_suspcount. 2278 */ 2279 thread_stopped(p); 2280 PROC_SUNLOCK(p); 2281 sigqueue_delete_proc(p, p->p_xstat); 2282 } else 2283 PROC_SUNLOCK(p); 2284 goto out; 2285 } 2286 } else { 2287 /* Not in "NORMAL" state. discard the signal. */ 2288 sigqueue_delete(sigqueue, sig); 2289 goto out; 2290 } 2291 2292 /* 2293 * The process is not stopped so we need to apply the signal to all the 2294 * running threads. 2295 */ 2296 runfast: 2297 tdsigwakeup(td, sig, action, intrval); 2298 PROC_SLOCK(p); 2299 thread_unsuspend(p); 2300 PROC_SUNLOCK(p); 2301 out: 2302 /* If we jump here, proc slock should not be owned. */ 2303 PROC_SLOCK_ASSERT(p, MA_NOTOWNED); 2304 return (ret); 2305 } 2306 2307 /* 2308 * The force of a signal has been directed against a single 2309 * thread. We need to see what we can do about knocking it 2310 * out of any sleep it may be in etc. 2311 */ 2312 static void 2313 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval) 2314 { 2315 struct proc *p = td->td_proc; 2316 register int prop; 2317 int wakeup_swapper; 2318 2319 wakeup_swapper = 0; 2320 PROC_LOCK_ASSERT(p, MA_OWNED); 2321 prop = sigprop(sig); 2322 2323 PROC_SLOCK(p); 2324 thread_lock(td); 2325 /* 2326 * Bring the priority of a thread up if we want it to get 2327 * killed in this lifetime. 2328 */ 2329 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER) 2330 sched_prio(td, PUSER); 2331 if (TD_ON_SLEEPQ(td)) { 2332 /* 2333 * If thread is sleeping uninterruptibly 2334 * we can't interrupt the sleep... the signal will 2335 * be noticed when the process returns through 2336 * trap() or syscall(). 2337 */ 2338 if ((td->td_flags & TDF_SINTR) == 0) 2339 goto out; 2340 /* 2341 * If SIGCONT is default (or ignored) and process is 2342 * asleep, we are finished; the process should not 2343 * be awakened. 2344 */ 2345 if ((prop & SA_CONT) && action == SIG_DFL) { 2346 thread_unlock(td); 2347 PROC_SUNLOCK(p); 2348 sigqueue_delete(&p->p_sigqueue, sig); 2349 /* 2350 * It may be on either list in this state. 2351 * Remove from both for now. 2352 */ 2353 sigqueue_delete(&td->td_sigqueue, sig); 2354 return; 2355 } 2356 2357 /* 2358 * Don't awaken a sleeping thread for SIGSTOP if the 2359 * STOP signal is deferred. 2360 */ 2361 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY)) 2362 goto out; 2363 2364 /* 2365 * Give low priority threads a better chance to run. 2366 */ 2367 if (td->td_priority > PUSER) 2368 sched_prio(td, PUSER); 2369 2370 wakeup_swapper = sleepq_abort(td, intrval); 2371 } else { 2372 /* 2373 * Other states do nothing with the signal immediately, 2374 * other than kicking ourselves if we are running. 2375 * It will either never be noticed, or noticed very soon. 2376 */ 2377 #ifdef SMP 2378 if (TD_IS_RUNNING(td) && td != curthread) 2379 forward_signal(td); 2380 #endif 2381 } 2382 out: 2383 PROC_SUNLOCK(p); 2384 thread_unlock(td); 2385 if (wakeup_swapper) 2386 kick_proc0(); 2387 } 2388 2389 static void 2390 sig_suspend_threads(struct thread *td, struct proc *p, int sending) 2391 { 2392 struct thread *td2; 2393 2394 PROC_LOCK_ASSERT(p, MA_OWNED); 2395 PROC_SLOCK_ASSERT(p, MA_OWNED); 2396 2397 FOREACH_THREAD_IN_PROC(p, td2) { 2398 thread_lock(td2); 2399 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK; 2400 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) && 2401 (td2->td_flags & TDF_SINTR)) { 2402 if (td2->td_flags & TDF_SBDRY) { 2403 /* 2404 * Once a thread is asleep with 2405 * TDF_SBDRY set, it should never 2406 * become suspended due to this check. 2407 */ 2408 KASSERT(!TD_IS_SUSPENDED(td2), 2409 ("thread with deferred stops suspended")); 2410 } else if (!TD_IS_SUSPENDED(td2)) { 2411 thread_suspend_one(td2); 2412 } 2413 } else if (!TD_IS_SUSPENDED(td2)) { 2414 if (sending || td != td2) 2415 td2->td_flags |= TDF_ASTPENDING; 2416 #ifdef SMP 2417 if (TD_IS_RUNNING(td2) && td2 != td) 2418 forward_signal(td2); 2419 #endif 2420 } 2421 thread_unlock(td2); 2422 } 2423 } 2424 2425 int 2426 ptracestop(struct thread *td, int sig) 2427 { 2428 struct proc *p = td->td_proc; 2429 2430 PROC_LOCK_ASSERT(p, MA_OWNED); 2431 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process")); 2432 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2433 &p->p_mtx.lock_object, "Stopping for traced signal"); 2434 2435 td->td_dbgflags |= TDB_XSIG; 2436 td->td_xsig = sig; 2437 PROC_SLOCK(p); 2438 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) { 2439 if (p->p_flag & P_SINGLE_EXIT) { 2440 td->td_dbgflags &= ~TDB_XSIG; 2441 PROC_SUNLOCK(p); 2442 return (sig); 2443 } 2444 /* 2445 * Just make wait() to work, the last stopped thread 2446 * will win. 2447 */ 2448 p->p_xstat = sig; 2449 p->p_xthread = td; 2450 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE); 2451 sig_suspend_threads(td, p, 0); 2452 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) { 2453 td->td_dbgflags &= ~TDB_STOPATFORK; 2454 cv_broadcast(&p->p_dbgwait); 2455 } 2456 stopme: 2457 thread_suspend_switch(td); 2458 if (p->p_xthread == td) 2459 p->p_xthread = NULL; 2460 if (!(p->p_flag & P_TRACED)) 2461 break; 2462 if (td->td_dbgflags & TDB_SUSPEND) { 2463 if (p->p_flag & P_SINGLE_EXIT) 2464 break; 2465 goto stopme; 2466 } 2467 } 2468 PROC_SUNLOCK(p); 2469 return (td->td_xsig); 2470 } 2471 2472 static void 2473 reschedule_signals(struct proc *p, sigset_t block, int flags) 2474 { 2475 struct sigacts *ps; 2476 struct thread *td; 2477 int sig; 2478 2479 PROC_LOCK_ASSERT(p, MA_OWNED); 2480 if (SIGISEMPTY(p->p_siglist)) 2481 return; 2482 ps = p->p_sigacts; 2483 SIGSETAND(block, p->p_siglist); 2484 while ((sig = sig_ffs(&block)) != 0) { 2485 SIGDELSET(block, sig); 2486 td = sigtd(p, sig, 0); 2487 signotify(td); 2488 if (!(flags & SIGPROCMASK_PS_LOCKED)) 2489 mtx_lock(&ps->ps_mtx); 2490 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig)) 2491 tdsigwakeup(td, sig, SIG_CATCH, 2492 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR : 2493 ERESTART)); 2494 if (!(flags & SIGPROCMASK_PS_LOCKED)) 2495 mtx_unlock(&ps->ps_mtx); 2496 } 2497 } 2498 2499 void 2500 tdsigcleanup(struct thread *td) 2501 { 2502 struct proc *p; 2503 sigset_t unblocked; 2504 2505 p = td->td_proc; 2506 PROC_LOCK_ASSERT(p, MA_OWNED); 2507 2508 sigqueue_flush(&td->td_sigqueue); 2509 if (p->p_numthreads == 1) 2510 return; 2511 2512 /* 2513 * Since we cannot handle signals, notify signal post code 2514 * about this by filling the sigmask. 2515 * 2516 * Also, if needed, wake up thread(s) that do not block the 2517 * same signals as the exiting thread, since the thread might 2518 * have been selected for delivery and woken up. 2519 */ 2520 SIGFILLSET(unblocked); 2521 SIGSETNAND(unblocked, td->td_sigmask); 2522 SIGFILLSET(td->td_sigmask); 2523 reschedule_signals(p, unblocked, 0); 2524 2525 } 2526 2527 /* 2528 * Defer the delivery of SIGSTOP for the current thread. Returns true 2529 * if stops were deferred and false if they were already deferred. 2530 */ 2531 int 2532 sigdeferstop(void) 2533 { 2534 struct thread *td; 2535 2536 td = curthread; 2537 if (td->td_flags & TDF_SBDRY) 2538 return (0); 2539 thread_lock(td); 2540 td->td_flags |= TDF_SBDRY; 2541 thread_unlock(td); 2542 return (1); 2543 } 2544 2545 /* 2546 * Permit the delivery of SIGSTOP for the current thread. This does 2547 * not immediately suspend if a stop was posted. Instead, the thread 2548 * will suspend either via ast() or a subsequent interruptible sleep. 2549 */ 2550 void 2551 sigallowstop() 2552 { 2553 struct thread *td; 2554 2555 td = curthread; 2556 thread_lock(td); 2557 td->td_flags &= ~TDF_SBDRY; 2558 thread_unlock(td); 2559 } 2560 2561 /* 2562 * If the current process has received a signal (should be caught or cause 2563 * termination, should interrupt current syscall), return the signal number. 2564 * Stop signals with default action are processed immediately, then cleared; 2565 * they aren't returned. This is checked after each entry to the system for 2566 * a syscall or trap (though this can usually be done without calling issignal 2567 * by checking the pending signal masks in cursig.) The normal call 2568 * sequence is 2569 * 2570 * while (sig = cursig(curthread)) 2571 * postsig(sig); 2572 */ 2573 static int 2574 issignal(struct thread *td) 2575 { 2576 struct proc *p; 2577 struct sigacts *ps; 2578 struct sigqueue *queue; 2579 sigset_t sigpending; 2580 int sig, prop, newsig; 2581 2582 p = td->td_proc; 2583 ps = p->p_sigacts; 2584 mtx_assert(&ps->ps_mtx, MA_OWNED); 2585 PROC_LOCK_ASSERT(p, MA_OWNED); 2586 for (;;) { 2587 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG); 2588 2589 sigpending = td->td_sigqueue.sq_signals; 2590 SIGSETOR(sigpending, p->p_sigqueue.sq_signals); 2591 SIGSETNAND(sigpending, td->td_sigmask); 2592 2593 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY) 2594 SIG_STOPSIGMASK(sigpending); 2595 if (SIGISEMPTY(sigpending)) /* no signal to send */ 2596 return (0); 2597 sig = sig_ffs(&sigpending); 2598 2599 if (p->p_stops & S_SIG) { 2600 mtx_unlock(&ps->ps_mtx); 2601 stopevent(p, S_SIG, sig); 2602 mtx_lock(&ps->ps_mtx); 2603 } 2604 2605 /* 2606 * We should see pending but ignored signals 2607 * only if P_TRACED was on when they were posted. 2608 */ 2609 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) { 2610 sigqueue_delete(&td->td_sigqueue, sig); 2611 sigqueue_delete(&p->p_sigqueue, sig); 2612 continue; 2613 } 2614 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) { 2615 /* 2616 * If traced, always stop. 2617 * Remove old signal from queue before the stop. 2618 * XXX shrug off debugger, it causes siginfo to 2619 * be thrown away. 2620 */ 2621 queue = &td->td_sigqueue; 2622 td->td_dbgksi.ksi_signo = 0; 2623 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) { 2624 queue = &p->p_sigqueue; 2625 sigqueue_get(queue, sig, &td->td_dbgksi); 2626 } 2627 2628 mtx_unlock(&ps->ps_mtx); 2629 newsig = ptracestop(td, sig); 2630 mtx_lock(&ps->ps_mtx); 2631 2632 if (sig != newsig) { 2633 2634 /* 2635 * If parent wants us to take the signal, 2636 * then it will leave it in p->p_xstat; 2637 * otherwise we just look for signals again. 2638 */ 2639 if (newsig == 0) 2640 continue; 2641 sig = newsig; 2642 2643 /* 2644 * Put the new signal into td_sigqueue. If the 2645 * signal is being masked, look for other 2646 * signals. 2647 */ 2648 sigqueue_add(queue, sig, NULL); 2649 if (SIGISMEMBER(td->td_sigmask, sig)) 2650 continue; 2651 signotify(td); 2652 } else { 2653 if (td->td_dbgksi.ksi_signo != 0) { 2654 td->td_dbgksi.ksi_flags |= KSI_HEAD; 2655 if (sigqueue_add(&td->td_sigqueue, sig, 2656 &td->td_dbgksi) != 0) 2657 td->td_dbgksi.ksi_signo = 0; 2658 } 2659 if (td->td_dbgksi.ksi_signo == 0) 2660 sigqueue_add(&td->td_sigqueue, sig, 2661 NULL); 2662 } 2663 2664 /* 2665 * If the traced bit got turned off, go back up 2666 * to the top to rescan signals. This ensures 2667 * that p_sig* and p_sigact are consistent. 2668 */ 2669 if ((p->p_flag & P_TRACED) == 0) 2670 continue; 2671 } 2672 2673 prop = sigprop(sig); 2674 2675 /* 2676 * Decide whether the signal should be returned. 2677 * Return the signal's number, or fall through 2678 * to clear it from the pending mask. 2679 */ 2680 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) { 2681 2682 case (intptr_t)SIG_DFL: 2683 /* 2684 * Don't take default actions on system processes. 2685 */ 2686 if (p->p_pid <= 1) { 2687 #ifdef DIAGNOSTIC 2688 /* 2689 * Are you sure you want to ignore SIGSEGV 2690 * in init? XXX 2691 */ 2692 printf("Process (pid %lu) got signal %d\n", 2693 (u_long)p->p_pid, sig); 2694 #endif 2695 break; /* == ignore */ 2696 } 2697 /* 2698 * If there is a pending stop signal to process 2699 * with default action, stop here, 2700 * then clear the signal. However, 2701 * if process is member of an orphaned 2702 * process group, ignore tty stop signals. 2703 */ 2704 if (prop & SA_STOP) { 2705 if (p->p_flag & (P_TRACED|P_WEXIT) || 2706 (p->p_pgrp->pg_jobc == 0 && 2707 prop & SA_TTYSTOP)) 2708 break; /* == ignore */ 2709 mtx_unlock(&ps->ps_mtx); 2710 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2711 &p->p_mtx.lock_object, "Catching SIGSTOP"); 2712 p->p_flag |= P_STOPPED_SIG; 2713 p->p_xstat = sig; 2714 PROC_SLOCK(p); 2715 sig_suspend_threads(td, p, 0); 2716 thread_suspend_switch(td); 2717 PROC_SUNLOCK(p); 2718 mtx_lock(&ps->ps_mtx); 2719 break; 2720 } else if (prop & SA_IGNORE) { 2721 /* 2722 * Except for SIGCONT, shouldn't get here. 2723 * Default action is to ignore; drop it. 2724 */ 2725 break; /* == ignore */ 2726 } else 2727 return (sig); 2728 /*NOTREACHED*/ 2729 2730 case (intptr_t)SIG_IGN: 2731 /* 2732 * Masking above should prevent us ever trying 2733 * to take action on an ignored signal other 2734 * than SIGCONT, unless process is traced. 2735 */ 2736 if ((prop & SA_CONT) == 0 && 2737 (p->p_flag & P_TRACED) == 0) 2738 printf("issignal\n"); 2739 break; /* == ignore */ 2740 2741 default: 2742 /* 2743 * This signal has an action, let 2744 * postsig() process it. 2745 */ 2746 return (sig); 2747 } 2748 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */ 2749 sigqueue_delete(&p->p_sigqueue, sig); 2750 } 2751 /* NOTREACHED */ 2752 } 2753 2754 void 2755 thread_stopped(struct proc *p) 2756 { 2757 int n; 2758 2759 PROC_LOCK_ASSERT(p, MA_OWNED); 2760 PROC_SLOCK_ASSERT(p, MA_OWNED); 2761 n = p->p_suspcount; 2762 if (p == curproc) 2763 n++; 2764 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) { 2765 PROC_SUNLOCK(p); 2766 p->p_flag &= ~P_WAITED; 2767 PROC_LOCK(p->p_pptr); 2768 childproc_stopped(p, (p->p_flag & P_TRACED) ? 2769 CLD_TRAPPED : CLD_STOPPED); 2770 PROC_UNLOCK(p->p_pptr); 2771 PROC_SLOCK(p); 2772 } 2773 } 2774 2775 /* 2776 * Take the action for the specified signal 2777 * from the current set of pending signals. 2778 */ 2779 int 2780 postsig(sig) 2781 register int sig; 2782 { 2783 struct thread *td = curthread; 2784 register struct proc *p = td->td_proc; 2785 struct sigacts *ps; 2786 sig_t action; 2787 ksiginfo_t ksi; 2788 sigset_t returnmask, mask; 2789 2790 KASSERT(sig != 0, ("postsig")); 2791 2792 PROC_LOCK_ASSERT(p, MA_OWNED); 2793 ps = p->p_sigacts; 2794 mtx_assert(&ps->ps_mtx, MA_OWNED); 2795 ksiginfo_init(&ksi); 2796 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 && 2797 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0) 2798 return (0); 2799 ksi.ksi_signo = sig; 2800 if (ksi.ksi_code == SI_TIMER) 2801 itimer_accept(p, ksi.ksi_timerid, &ksi); 2802 action = ps->ps_sigact[_SIG_IDX(sig)]; 2803 #ifdef KTRACE 2804 if (KTRPOINT(td, KTR_PSIG)) 2805 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ? 2806 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code); 2807 #endif 2808 if (p->p_stops & S_SIG) { 2809 mtx_unlock(&ps->ps_mtx); 2810 stopevent(p, S_SIG, sig); 2811 mtx_lock(&ps->ps_mtx); 2812 } 2813 2814 if (action == SIG_DFL) { 2815 /* 2816 * Default action, where the default is to kill 2817 * the process. (Other cases were ignored above.) 2818 */ 2819 mtx_unlock(&ps->ps_mtx); 2820 sigexit(td, sig); 2821 /* NOTREACHED */ 2822 } else { 2823 /* 2824 * If we get here, the signal must be caught. 2825 */ 2826 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig), 2827 ("postsig action")); 2828 /* 2829 * Set the new mask value and also defer further 2830 * occurrences of this signal. 2831 * 2832 * Special case: user has done a sigsuspend. Here the 2833 * current mask is not of interest, but rather the 2834 * mask from before the sigsuspend is what we want 2835 * restored after the signal processing is completed. 2836 */ 2837 if (td->td_pflags & TDP_OLDMASK) { 2838 returnmask = td->td_oldsigmask; 2839 td->td_pflags &= ~TDP_OLDMASK; 2840 } else 2841 returnmask = td->td_sigmask; 2842 2843 mask = ps->ps_catchmask[_SIG_IDX(sig)]; 2844 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 2845 SIGADDSET(mask, sig); 2846 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL, 2847 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED); 2848 2849 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 2850 /* 2851 * See kern_sigaction() for origin of this code. 2852 */ 2853 SIGDELSET(ps->ps_sigcatch, sig); 2854 if (sig != SIGCONT && 2855 sigprop(sig) & SA_IGNORE) 2856 SIGADDSET(ps->ps_sigignore, sig); 2857 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 2858 } 2859 td->td_ru.ru_nsignals++; 2860 if (p->p_sig == sig) { 2861 p->p_code = 0; 2862 p->p_sig = 0; 2863 } 2864 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask); 2865 } 2866 return (1); 2867 } 2868 2869 /* 2870 * Kill the current process for stated reason. 2871 */ 2872 void 2873 killproc(p, why) 2874 struct proc *p; 2875 char *why; 2876 { 2877 2878 PROC_LOCK_ASSERT(p, MA_OWNED); 2879 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid, 2880 p->p_comm); 2881 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, 2882 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why); 2883 p->p_flag |= P_WKILLED; 2884 kern_psignal(p, SIGKILL); 2885 } 2886 2887 /* 2888 * Force the current process to exit with the specified signal, dumping core 2889 * if appropriate. We bypass the normal tests for masked and caught signals, 2890 * allowing unrecoverable failures to terminate the process without changing 2891 * signal state. Mark the accounting record with the signal termination. 2892 * If dumping core, save the signal number for the debugger. Calls exit and 2893 * does not return. 2894 */ 2895 void 2896 sigexit(td, sig) 2897 struct thread *td; 2898 int sig; 2899 { 2900 struct proc *p = td->td_proc; 2901 2902 PROC_LOCK_ASSERT(p, MA_OWNED); 2903 p->p_acflag |= AXSIG; 2904 /* 2905 * We must be single-threading to generate a core dump. This 2906 * ensures that the registers in the core file are up-to-date. 2907 * Also, the ELF dump handler assumes that the thread list doesn't 2908 * change out from under it. 2909 * 2910 * XXX If another thread attempts to single-thread before us 2911 * (e.g. via fork()), we won't get a dump at all. 2912 */ 2913 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) { 2914 p->p_sig = sig; 2915 /* 2916 * Log signals which would cause core dumps 2917 * (Log as LOG_INFO to appease those who don't want 2918 * these messages.) 2919 * XXX : Todo, as well as euid, write out ruid too 2920 * Note that coredump() drops proc lock. 2921 */ 2922 if (coredump(td) == 0) 2923 sig |= WCOREFLAG; 2924 if (kern_logsigexit) 2925 log(LOG_INFO, 2926 "pid %d (%s), uid %d: exited on signal %d%s\n", 2927 p->p_pid, p->p_comm, 2928 td->td_ucred ? td->td_ucred->cr_uid : -1, 2929 sig &~ WCOREFLAG, 2930 sig & WCOREFLAG ? " (core dumped)" : ""); 2931 } else 2932 PROC_UNLOCK(p); 2933 exit1(td, W_EXITCODE(0, sig)); 2934 /* NOTREACHED */ 2935 } 2936 2937 /* 2938 * Send queued SIGCHLD to parent when child process's state 2939 * is changed. 2940 */ 2941 static void 2942 sigparent(struct proc *p, int reason, int status) 2943 { 2944 PROC_LOCK_ASSERT(p, MA_OWNED); 2945 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED); 2946 2947 if (p->p_ksi != NULL) { 2948 p->p_ksi->ksi_signo = SIGCHLD; 2949 p->p_ksi->ksi_code = reason; 2950 p->p_ksi->ksi_status = status; 2951 p->p_ksi->ksi_pid = p->p_pid; 2952 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid; 2953 if (KSI_ONQ(p->p_ksi)) 2954 return; 2955 } 2956 pksignal(p->p_pptr, SIGCHLD, p->p_ksi); 2957 } 2958 2959 static void 2960 childproc_jobstate(struct proc *p, int reason, int status) 2961 { 2962 struct sigacts *ps; 2963 2964 PROC_LOCK_ASSERT(p, MA_OWNED); 2965 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED); 2966 2967 /* 2968 * Wake up parent sleeping in kern_wait(), also send 2969 * SIGCHLD to parent, but SIGCHLD does not guarantee 2970 * that parent will awake, because parent may masked 2971 * the signal. 2972 */ 2973 p->p_pptr->p_flag |= P_STATCHILD; 2974 wakeup(p->p_pptr); 2975 2976 ps = p->p_pptr->p_sigacts; 2977 mtx_lock(&ps->ps_mtx); 2978 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) { 2979 mtx_unlock(&ps->ps_mtx); 2980 sigparent(p, reason, status); 2981 } else 2982 mtx_unlock(&ps->ps_mtx); 2983 } 2984 2985 void 2986 childproc_stopped(struct proc *p, int reason) 2987 { 2988 childproc_jobstate(p, reason, p->p_xstat); 2989 } 2990 2991 void 2992 childproc_continued(struct proc *p) 2993 { 2994 childproc_jobstate(p, CLD_CONTINUED, SIGCONT); 2995 } 2996 2997 void 2998 childproc_exited(struct proc *p) 2999 { 3000 int reason; 3001 int status = p->p_xstat; /* convert to int */ 3002 3003 reason = CLD_EXITED; 3004 if (WCOREDUMP(status)) 3005 reason = CLD_DUMPED; 3006 else if (WIFSIGNALED(status)) 3007 reason = CLD_KILLED; 3008 /* 3009 * XXX avoid calling wakeup(p->p_pptr), the work is 3010 * done in exit1(). 3011 */ 3012 sigparent(p, reason, status); 3013 } 3014 3015 /* 3016 * We only have 1 character for the core count in the format 3017 * string, so the range will be 0-9 3018 */ 3019 #define MAX_NUM_CORES 10 3020 static int num_cores = 5; 3021 3022 static int 3023 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS) 3024 { 3025 int error; 3026 int new_val; 3027 3028 new_val = num_cores; 3029 error = sysctl_handle_int(oidp, &new_val, 0, req); 3030 if (error != 0 || req->newptr == NULL) 3031 return (error); 3032 if (new_val > MAX_NUM_CORES) 3033 new_val = MAX_NUM_CORES; 3034 if (new_val < 0) 3035 new_val = 0; 3036 num_cores = new_val; 3037 return (0); 3038 } 3039 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW, 3040 0, sizeof(int), sysctl_debug_num_cores_check, "I", ""); 3041 3042 #if defined(COMPRESS_USER_CORES) 3043 int compress_user_cores = 1; 3044 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW, 3045 &compress_user_cores, 0, "Compression of user corefiles"); 3046 3047 int compress_user_cores_gzlevel = -1; /* default level */ 3048 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW, 3049 &compress_user_cores_gzlevel, -1, "Corefile gzip compression level"); 3050 3051 #define GZ_SUFFIX ".gz" 3052 #define GZ_SUFFIX_LEN 3 3053 #endif 3054 3055 static char corefilename[MAXPATHLEN] = {"%N.core"}; 3056 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename)); 3057 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename, 3058 sizeof(corefilename), "Process corefile name format string"); 3059 3060 /* 3061 * corefile_open(comm, uid, pid, td, compress, vpp, namep) 3062 * Expand the name described in corefilename, using name, uid, and pid 3063 * and open/create core file. 3064 * corefilename is a printf-like string, with three format specifiers: 3065 * %N name of process ("name") 3066 * %P process id (pid) 3067 * %U user id (uid) 3068 * For example, "%N.core" is the default; they can be disabled completely 3069 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P". 3070 * This is controlled by the sysctl variable kern.corefile (see above). 3071 */ 3072 static int 3073 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td, 3074 int compress, struct vnode **vpp, char **namep) 3075 { 3076 struct nameidata nd; 3077 struct sbuf sb; 3078 const char *format; 3079 char *hostname, *name; 3080 int indexpos, i, error, cmode, flags, oflags; 3081 3082 hostname = NULL; 3083 format = corefilename; 3084 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO); 3085 indexpos = -1; 3086 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN); 3087 for (i = 0; format[i] != '\0'; i++) { 3088 switch (format[i]) { 3089 case '%': /* Format character */ 3090 i++; 3091 switch (format[i]) { 3092 case '%': 3093 sbuf_putc(&sb, '%'); 3094 break; 3095 case 'H': /* hostname */ 3096 if (hostname == NULL) { 3097 hostname = malloc(MAXHOSTNAMELEN, 3098 M_TEMP, M_WAITOK); 3099 } 3100 getcredhostname(td->td_ucred, hostname, 3101 MAXHOSTNAMELEN); 3102 sbuf_printf(&sb, "%s", hostname); 3103 break; 3104 case 'I': /* autoincrementing index */ 3105 sbuf_printf(&sb, "0"); 3106 indexpos = sbuf_len(&sb) - 1; 3107 break; 3108 case 'N': /* process name */ 3109 sbuf_printf(&sb, "%s", comm); 3110 break; 3111 case 'P': /* process id */ 3112 sbuf_printf(&sb, "%u", pid); 3113 break; 3114 case 'U': /* user id */ 3115 sbuf_printf(&sb, "%u", uid); 3116 break; 3117 default: 3118 log(LOG_ERR, 3119 "Unknown format character %c in " 3120 "corename `%s'\n", format[i], format); 3121 break; 3122 } 3123 break; 3124 default: 3125 sbuf_putc(&sb, format[i]); 3126 break; 3127 } 3128 } 3129 free(hostname, M_TEMP); 3130 #ifdef COMPRESS_USER_CORES 3131 if (compress) 3132 sbuf_printf(&sb, GZ_SUFFIX); 3133 #endif 3134 if (sbuf_error(&sb) != 0) { 3135 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too " 3136 "long\n", (long)pid, comm, (u_long)uid); 3137 sbuf_delete(&sb); 3138 free(name, M_TEMP); 3139 return (ENOMEM); 3140 } 3141 sbuf_finish(&sb); 3142 sbuf_delete(&sb); 3143 3144 cmode = S_IRUSR | S_IWUSR; 3145 oflags = VN_OPEN_NOAUDIT | (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0); 3146 3147 /* 3148 * If the core format has a %I in it, then we need to check 3149 * for existing corefiles before returning a name. 3150 * To do this we iterate over 0..num_cores to find a 3151 * non-existing core file name to use. 3152 */ 3153 if (indexpos != -1) { 3154 for (i = 0; i < num_cores; i++) { 3155 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW; 3156 name[indexpos] = '0' + i; 3157 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); 3158 error = vn_open_cred(&nd, &flags, cmode, oflags, 3159 td->td_ucred, NULL); 3160 if (error) { 3161 if (error == EEXIST) 3162 continue; 3163 log(LOG_ERR, 3164 "pid %d (%s), uid (%u): Path `%s' failed " 3165 "on initial open test, error = %d\n", 3166 pid, comm, uid, name, error); 3167 } 3168 goto out; 3169 } 3170 } 3171 3172 flags = O_CREAT | FWRITE | O_NOFOLLOW; 3173 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); 3174 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL); 3175 out: 3176 if (error) { 3177 #ifdef AUDIT 3178 audit_proc_coredump(td, name, error); 3179 #endif 3180 free(name, M_TEMP); 3181 return (error); 3182 } 3183 NDFREE(&nd, NDF_ONLY_PNBUF); 3184 *vpp = nd.ni_vp; 3185 *namep = name; 3186 return (0); 3187 } 3188 3189 /* 3190 * Dump a process' core. The main routine does some 3191 * policy checking, and creates the name of the coredump; 3192 * then it passes on a vnode and a size limit to the process-specific 3193 * coredump routine if there is one; if there _is not_ one, it returns 3194 * ENOSYS; otherwise it returns the error from the process-specific routine. 3195 */ 3196 3197 static int 3198 coredump(struct thread *td) 3199 { 3200 struct proc *p = td->td_proc; 3201 struct ucred *cred = td->td_ucred; 3202 struct vnode *vp; 3203 struct flock lf; 3204 struct vattr vattr; 3205 int error, error1, locked; 3206 struct mount *mp; 3207 char *name; /* name of corefile */ 3208 off_t limit; 3209 int compress; 3210 3211 #ifdef COMPRESS_USER_CORES 3212 compress = compress_user_cores; 3213 #else 3214 compress = 0; 3215 #endif 3216 PROC_LOCK_ASSERT(p, MA_OWNED); 3217 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td); 3218 _STOPEVENT(p, S_CORE, 0); 3219 3220 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0)) { 3221 PROC_UNLOCK(p); 3222 return (EFAULT); 3223 } 3224 3225 /* 3226 * Note that the bulk of limit checking is done after 3227 * the corefile is created. The exception is if the limit 3228 * for corefiles is 0, in which case we don't bother 3229 * creating the corefile at all. This layout means that 3230 * a corefile is truncated instead of not being created, 3231 * if it is larger than the limit. 3232 */ 3233 limit = (off_t)lim_cur(p, RLIMIT_CORE); 3234 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) { 3235 PROC_UNLOCK(p); 3236 return (EFBIG); 3237 } 3238 PROC_UNLOCK(p); 3239 3240 restart: 3241 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress, 3242 &vp, &name); 3243 if (error != 0) 3244 return (error); 3245 3246 /* Don't dump to non-regular files or files with links. */ 3247 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 || 3248 vattr.va_nlink != 1) { 3249 VOP_UNLOCK(vp, 0); 3250 error = EFAULT; 3251 goto close; 3252 } 3253 3254 VOP_UNLOCK(vp, 0); 3255 lf.l_whence = SEEK_SET; 3256 lf.l_start = 0; 3257 lf.l_len = 0; 3258 lf.l_type = F_WRLCK; 3259 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0); 3260 3261 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 3262 lf.l_type = F_UNLCK; 3263 if (locked) 3264 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 3265 if ((error = vn_close(vp, FWRITE, cred, td)) != 0) 3266 goto out; 3267 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0) 3268 goto out; 3269 free(name, M_TEMP); 3270 goto restart; 3271 } 3272 3273 VATTR_NULL(&vattr); 3274 vattr.va_size = 0; 3275 if (set_core_nodump_flag) 3276 vattr.va_flags = UF_NODUMP; 3277 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3278 VOP_SETATTR(vp, &vattr, cred); 3279 VOP_UNLOCK(vp, 0); 3280 vn_finished_write(mp); 3281 PROC_LOCK(p); 3282 p->p_acflag |= ACORE; 3283 PROC_UNLOCK(p); 3284 3285 if (p->p_sysent->sv_coredump != NULL) { 3286 error = p->p_sysent->sv_coredump(td, vp, limit, 3287 compress ? IMGACT_CORE_COMPRESS : 0); 3288 } else { 3289 error = ENOSYS; 3290 } 3291 3292 if (locked) { 3293 lf.l_type = F_UNLCK; 3294 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 3295 } 3296 close: 3297 error1 = vn_close(vp, FWRITE, cred, td); 3298 if (error == 0) 3299 error = error1; 3300 out: 3301 #ifdef AUDIT 3302 audit_proc_coredump(td, name, error); 3303 #endif 3304 free(name, M_TEMP); 3305 return (error); 3306 } 3307 3308 /* 3309 * Nonexistent system call-- signal process (may want to handle it). Flag 3310 * error in case process won't see signal immediately (blocked or ignored). 3311 */ 3312 #ifndef _SYS_SYSPROTO_H_ 3313 struct nosys_args { 3314 int dummy; 3315 }; 3316 #endif 3317 /* ARGSUSED */ 3318 int 3319 nosys(td, args) 3320 struct thread *td; 3321 struct nosys_args *args; 3322 { 3323 struct proc *p = td->td_proc; 3324 3325 PROC_LOCK(p); 3326 tdsignal(td, SIGSYS); 3327 PROC_UNLOCK(p); 3328 return (ENOSYS); 3329 } 3330 3331 /* 3332 * Send a SIGIO or SIGURG signal to a process or process group using stored 3333 * credentials rather than those of the current process. 3334 */ 3335 void 3336 pgsigio(sigiop, sig, checkctty) 3337 struct sigio **sigiop; 3338 int sig, checkctty; 3339 { 3340 ksiginfo_t ksi; 3341 struct sigio *sigio; 3342 3343 ksiginfo_init(&ksi); 3344 ksi.ksi_signo = sig; 3345 ksi.ksi_code = SI_KERNEL; 3346 3347 SIGIO_LOCK(); 3348 sigio = *sigiop; 3349 if (sigio == NULL) { 3350 SIGIO_UNLOCK(); 3351 return; 3352 } 3353 if (sigio->sio_pgid > 0) { 3354 PROC_LOCK(sigio->sio_proc); 3355 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred)) 3356 kern_psignal(sigio->sio_proc, sig); 3357 PROC_UNLOCK(sigio->sio_proc); 3358 } else if (sigio->sio_pgid < 0) { 3359 struct proc *p; 3360 3361 PGRP_LOCK(sigio->sio_pgrp); 3362 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) { 3363 PROC_LOCK(p); 3364 if (p->p_state == PRS_NORMAL && 3365 CANSIGIO(sigio->sio_ucred, p->p_ucred) && 3366 (checkctty == 0 || (p->p_flag & P_CONTROLT))) 3367 kern_psignal(p, sig); 3368 PROC_UNLOCK(p); 3369 } 3370 PGRP_UNLOCK(sigio->sio_pgrp); 3371 } 3372 SIGIO_UNLOCK(); 3373 } 3374 3375 static int 3376 filt_sigattach(struct knote *kn) 3377 { 3378 struct proc *p = curproc; 3379 3380 kn->kn_ptr.p_proc = p; 3381 kn->kn_flags |= EV_CLEAR; /* automatically set */ 3382 3383 knlist_add(&p->p_klist, kn, 0); 3384 3385 return (0); 3386 } 3387 3388 static void 3389 filt_sigdetach(struct knote *kn) 3390 { 3391 struct proc *p = kn->kn_ptr.p_proc; 3392 3393 knlist_remove(&p->p_klist, kn, 0); 3394 } 3395 3396 /* 3397 * signal knotes are shared with proc knotes, so we apply a mask to 3398 * the hint in order to differentiate them from process hints. This 3399 * could be avoided by using a signal-specific knote list, but probably 3400 * isn't worth the trouble. 3401 */ 3402 static int 3403 filt_signal(struct knote *kn, long hint) 3404 { 3405 3406 if (hint & NOTE_SIGNAL) { 3407 hint &= ~NOTE_SIGNAL; 3408 3409 if (kn->kn_id == hint) 3410 kn->kn_data++; 3411 } 3412 return (kn->kn_data != 0); 3413 } 3414 3415 struct sigacts * 3416 sigacts_alloc(void) 3417 { 3418 struct sigacts *ps; 3419 3420 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO); 3421 ps->ps_refcnt = 1; 3422 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF); 3423 return (ps); 3424 } 3425 3426 void 3427 sigacts_free(struct sigacts *ps) 3428 { 3429 3430 mtx_lock(&ps->ps_mtx); 3431 ps->ps_refcnt--; 3432 if (ps->ps_refcnt == 0) { 3433 mtx_destroy(&ps->ps_mtx); 3434 free(ps, M_SUBPROC); 3435 } else 3436 mtx_unlock(&ps->ps_mtx); 3437 } 3438 3439 struct sigacts * 3440 sigacts_hold(struct sigacts *ps) 3441 { 3442 mtx_lock(&ps->ps_mtx); 3443 ps->ps_refcnt++; 3444 mtx_unlock(&ps->ps_mtx); 3445 return (ps); 3446 } 3447 3448 void 3449 sigacts_copy(struct sigacts *dest, struct sigacts *src) 3450 { 3451 3452 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest")); 3453 mtx_lock(&src->ps_mtx); 3454 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt)); 3455 mtx_unlock(&src->ps_mtx); 3456 } 3457 3458 int 3459 sigacts_shared(struct sigacts *ps) 3460 { 3461 int shared; 3462 3463 mtx_lock(&ps->ps_mtx); 3464 shared = ps->ps_refcnt > 1; 3465 mtx_unlock(&ps->ps_mtx); 3466 return (shared); 3467 } 3468