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_ktrace.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/signalvar.h> 46 #include <sys/vnode.h> 47 #include <sys/acct.h> 48 #include <sys/condvar.h> 49 #include <sys/event.h> 50 #include <sys/fcntl.h> 51 #include <sys/kernel.h> 52 #include <sys/kse.h> 53 #include <sys/ktr.h> 54 #include <sys/ktrace.h> 55 #include <sys/lock.h> 56 #include <sys/malloc.h> 57 #include <sys/mutex.h> 58 #include <sys/namei.h> 59 #include <sys/proc.h> 60 #include <sys/pioctl.h> 61 #include <sys/resourcevar.h> 62 #include <sys/sleepqueue.h> 63 #include <sys/smp.h> 64 #include <sys/stat.h> 65 #include <sys/sx.h> 66 #include <sys/syscallsubr.h> 67 #include <sys/sysctl.h> 68 #include <sys/sysent.h> 69 #include <sys/syslog.h> 70 #include <sys/sysproto.h> 71 #include <sys/unistd.h> 72 #include <sys/wait.h> 73 74 #include <machine/cpu.h> 75 76 #if defined (__alpha__) && !defined(COMPAT_43) 77 #error "You *really* need COMPAT_43 on the alpha for longjmp(3)" 78 #endif 79 80 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */ 81 82 static int coredump(struct thread *); 83 static char *expand_name(const char *, uid_t, pid_t); 84 static int killpg1(struct thread *td, int sig, int pgid, int all); 85 static int issignal(struct thread *p); 86 static int sigprop(int sig); 87 static void stop(struct proc *); 88 static void tdsigwakeup(struct thread *td, int sig, sig_t action); 89 static int filt_sigattach(struct knote *kn); 90 static void filt_sigdetach(struct knote *kn); 91 static int filt_signal(struct knote *kn, long hint); 92 static struct thread *sigtd(struct proc *p, int sig, int prop); 93 static int kern_sigtimedwait(struct thread *td, sigset_t set, 94 siginfo_t *info, struct timespec *timeout); 95 static void do_tdsignal(struct thread *td, int sig, sigtarget_t target); 96 97 struct filterops sig_filtops = 98 { 0, filt_sigattach, filt_sigdetach, filt_signal }; 99 100 static int kern_logsigexit = 1; 101 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW, 102 &kern_logsigexit, 0, 103 "Log processes quitting on abnormal signals to syslog(3)"); 104 105 /* 106 * Policy -- Can ucred cr1 send SIGIO to process cr2? 107 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG 108 * in the right situations. 109 */ 110 #define CANSIGIO(cr1, cr2) \ 111 ((cr1)->cr_uid == 0 || \ 112 (cr1)->cr_ruid == (cr2)->cr_ruid || \ 113 (cr1)->cr_uid == (cr2)->cr_ruid || \ 114 (cr1)->cr_ruid == (cr2)->cr_uid || \ 115 (cr1)->cr_uid == (cr2)->cr_uid) 116 117 int sugid_coredump; 118 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW, 119 &sugid_coredump, 0, "Enable coredumping set user/group ID processes"); 120 121 static int do_coredump = 1; 122 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW, 123 &do_coredump, 0, "Enable/Disable coredumps"); 124 125 /* 126 * Signal properties and actions. 127 * The array below categorizes the signals and their default actions 128 * according to the following properties: 129 */ 130 #define SA_KILL 0x01 /* terminates process by default */ 131 #define SA_CORE 0x02 /* ditto and coredumps */ 132 #define SA_STOP 0x04 /* suspend process */ 133 #define SA_TTYSTOP 0x08 /* ditto, from tty */ 134 #define SA_IGNORE 0x10 /* ignore by default */ 135 #define SA_CONT 0x20 /* continue if suspended */ 136 #define SA_CANTMASK 0x40 /* non-maskable, catchable */ 137 #define SA_PROC 0x80 /* deliverable to any thread */ 138 139 static int sigproptbl[NSIG] = { 140 SA_KILL|SA_PROC, /* SIGHUP */ 141 SA_KILL|SA_PROC, /* SIGINT */ 142 SA_KILL|SA_CORE|SA_PROC, /* SIGQUIT */ 143 SA_KILL|SA_CORE, /* SIGILL */ 144 SA_KILL|SA_CORE, /* SIGTRAP */ 145 SA_KILL|SA_CORE, /* SIGABRT */ 146 SA_KILL|SA_CORE|SA_PROC, /* SIGEMT */ 147 SA_KILL|SA_CORE, /* SIGFPE */ 148 SA_KILL|SA_PROC, /* SIGKILL */ 149 SA_KILL|SA_CORE, /* SIGBUS */ 150 SA_KILL|SA_CORE, /* SIGSEGV */ 151 SA_KILL|SA_CORE, /* SIGSYS */ 152 SA_KILL|SA_PROC, /* SIGPIPE */ 153 SA_KILL|SA_PROC, /* SIGALRM */ 154 SA_KILL|SA_PROC, /* SIGTERM */ 155 SA_IGNORE|SA_PROC, /* SIGURG */ 156 SA_STOP|SA_PROC, /* SIGSTOP */ 157 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTSTP */ 158 SA_IGNORE|SA_CONT|SA_PROC, /* SIGCONT */ 159 SA_IGNORE|SA_PROC, /* SIGCHLD */ 160 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTIN */ 161 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTOU */ 162 SA_IGNORE|SA_PROC, /* SIGIO */ 163 SA_KILL, /* SIGXCPU */ 164 SA_KILL, /* SIGXFSZ */ 165 SA_KILL|SA_PROC, /* SIGVTALRM */ 166 SA_KILL|SA_PROC, /* SIGPROF */ 167 SA_IGNORE|SA_PROC, /* SIGWINCH */ 168 SA_IGNORE|SA_PROC, /* SIGINFO */ 169 SA_KILL|SA_PROC, /* SIGUSR1 */ 170 SA_KILL|SA_PROC, /* SIGUSR2 */ 171 }; 172 173 /* 174 * Determine signal that should be delivered to process p, the current 175 * process, 0 if none. If there is a pending stop signal with default 176 * action, the process stops in issignal(). 177 * XXXKSE the check for a pending stop is not done under KSE 178 * 179 * MP SAFE. 180 */ 181 int 182 cursig(struct thread *td) 183 { 184 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 185 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED); 186 mtx_assert(&sched_lock, MA_NOTOWNED); 187 return (SIGPENDING(td) ? issignal(td) : 0); 188 } 189 190 /* 191 * Arrange for ast() to handle unmasked pending signals on return to user 192 * mode. This must be called whenever a signal is added to td_siglist or 193 * unmasked in td_sigmask. 194 */ 195 void 196 signotify(struct thread *td) 197 { 198 struct proc *p; 199 sigset_t set, saved; 200 201 p = td->td_proc; 202 203 PROC_LOCK_ASSERT(p, MA_OWNED); 204 205 /* 206 * If our mask changed we may have to move signal that were 207 * previously masked by all threads to our siglist. 208 */ 209 set = p->p_siglist; 210 if (p->p_flag & P_SA) 211 saved = p->p_siglist; 212 SIGSETNAND(set, td->td_sigmask); 213 SIGSETNAND(p->p_siglist, set); 214 SIGSETOR(td->td_siglist, set); 215 216 if (SIGPENDING(td)) { 217 mtx_lock_spin(&sched_lock); 218 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING; 219 mtx_unlock_spin(&sched_lock); 220 } 221 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) { 222 if (SIGSETEQ(saved, p->p_siglist)) 223 return; 224 else { 225 /* pending set changed */ 226 p->p_flag |= P_SIGEVENT; 227 wakeup(&p->p_siglist); 228 } 229 } 230 } 231 232 int 233 sigonstack(size_t sp) 234 { 235 struct thread *td = curthread; 236 237 return ((td->td_pflags & TDP_ALTSTACK) ? 238 #if defined(COMPAT_43) 239 ((td->td_sigstk.ss_size == 0) ? 240 (td->td_sigstk.ss_flags & SS_ONSTACK) : 241 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)) 242 #else 243 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size) 244 #endif 245 : 0); 246 } 247 248 static __inline int 249 sigprop(int sig) 250 { 251 252 if (sig > 0 && sig < NSIG) 253 return (sigproptbl[_SIG_IDX(sig)]); 254 return (0); 255 } 256 257 int 258 sig_ffs(sigset_t *set) 259 { 260 int i; 261 262 for (i = 0; i < _SIG_WORDS; i++) 263 if (set->__bits[i]) 264 return (ffs(set->__bits[i]) + (i * 32)); 265 return (0); 266 } 267 268 /* 269 * kern_sigaction 270 * sigaction 271 * freebsd4_sigaction 272 * osigaction 273 * 274 * MPSAFE 275 */ 276 int 277 kern_sigaction(td, sig, act, oact, flags) 278 struct thread *td; 279 register int sig; 280 struct sigaction *act, *oact; 281 int flags; 282 { 283 struct sigacts *ps; 284 struct thread *td0; 285 struct proc *p = td->td_proc; 286 287 if (!_SIG_VALID(sig)) 288 return (EINVAL); 289 290 PROC_LOCK(p); 291 ps = p->p_sigacts; 292 mtx_lock(&ps->ps_mtx); 293 if (oact) { 294 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)]; 295 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)]; 296 oact->sa_flags = 0; 297 if (SIGISMEMBER(ps->ps_sigonstack, sig)) 298 oact->sa_flags |= SA_ONSTACK; 299 if (!SIGISMEMBER(ps->ps_sigintr, sig)) 300 oact->sa_flags |= SA_RESTART; 301 if (SIGISMEMBER(ps->ps_sigreset, sig)) 302 oact->sa_flags |= SA_RESETHAND; 303 if (SIGISMEMBER(ps->ps_signodefer, sig)) 304 oact->sa_flags |= SA_NODEFER; 305 if (SIGISMEMBER(ps->ps_siginfo, sig)) 306 oact->sa_flags |= SA_SIGINFO; 307 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP) 308 oact->sa_flags |= SA_NOCLDSTOP; 309 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT) 310 oact->sa_flags |= SA_NOCLDWAIT; 311 } 312 if (act) { 313 if ((sig == SIGKILL || sig == SIGSTOP) && 314 act->sa_handler != SIG_DFL) { 315 mtx_unlock(&ps->ps_mtx); 316 PROC_UNLOCK(p); 317 return (EINVAL); 318 } 319 320 /* 321 * Change setting atomically. 322 */ 323 324 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask; 325 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]); 326 if (act->sa_flags & SA_SIGINFO) { 327 ps->ps_sigact[_SIG_IDX(sig)] = 328 (__sighandler_t *)act->sa_sigaction; 329 SIGADDSET(ps->ps_siginfo, sig); 330 } else { 331 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler; 332 SIGDELSET(ps->ps_siginfo, sig); 333 } 334 if (!(act->sa_flags & SA_RESTART)) 335 SIGADDSET(ps->ps_sigintr, sig); 336 else 337 SIGDELSET(ps->ps_sigintr, sig); 338 if (act->sa_flags & SA_ONSTACK) 339 SIGADDSET(ps->ps_sigonstack, sig); 340 else 341 SIGDELSET(ps->ps_sigonstack, sig); 342 if (act->sa_flags & SA_RESETHAND) 343 SIGADDSET(ps->ps_sigreset, sig); 344 else 345 SIGDELSET(ps->ps_sigreset, sig); 346 if (act->sa_flags & SA_NODEFER) 347 SIGADDSET(ps->ps_signodefer, sig); 348 else 349 SIGDELSET(ps->ps_signodefer, sig); 350 if (sig == SIGCHLD) { 351 if (act->sa_flags & SA_NOCLDSTOP) 352 ps->ps_flag |= PS_NOCLDSTOP; 353 else 354 ps->ps_flag &= ~PS_NOCLDSTOP; 355 if (act->sa_flags & SA_NOCLDWAIT) { 356 /* 357 * Paranoia: since SA_NOCLDWAIT is implemented 358 * by reparenting the dying child to PID 1 (and 359 * trust it to reap the zombie), PID 1 itself 360 * is forbidden to set SA_NOCLDWAIT. 361 */ 362 if (p->p_pid == 1) 363 ps->ps_flag &= ~PS_NOCLDWAIT; 364 else 365 ps->ps_flag |= PS_NOCLDWAIT; 366 } else 367 ps->ps_flag &= ~PS_NOCLDWAIT; 368 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 369 ps->ps_flag |= PS_CLDSIGIGN; 370 else 371 ps->ps_flag &= ~PS_CLDSIGIGN; 372 } 373 /* 374 * Set bit in ps_sigignore for signals that are set to SIG_IGN, 375 * and for signals set to SIG_DFL where the default is to 376 * ignore. However, don't put SIGCONT in ps_sigignore, as we 377 * have to restart the process. 378 */ 379 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 380 (sigprop(sig) & SA_IGNORE && 381 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) { 382 if ((p->p_flag & P_SA) && 383 SIGISMEMBER(p->p_siglist, sig)) { 384 p->p_flag |= P_SIGEVENT; 385 wakeup(&p->p_siglist); 386 } 387 /* never to be seen again */ 388 SIGDELSET(p->p_siglist, sig); 389 mtx_lock_spin(&sched_lock); 390 FOREACH_THREAD_IN_PROC(p, td0) 391 SIGDELSET(td0->td_siglist, sig); 392 mtx_unlock_spin(&sched_lock); 393 if (sig != SIGCONT) 394 /* easier in psignal */ 395 SIGADDSET(ps->ps_sigignore, sig); 396 SIGDELSET(ps->ps_sigcatch, sig); 397 } else { 398 SIGDELSET(ps->ps_sigignore, sig); 399 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL) 400 SIGDELSET(ps->ps_sigcatch, sig); 401 else 402 SIGADDSET(ps->ps_sigcatch, sig); 403 } 404 #ifdef COMPAT_FREEBSD4 405 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 406 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 407 (flags & KSA_FREEBSD4) == 0) 408 SIGDELSET(ps->ps_freebsd4, sig); 409 else 410 SIGADDSET(ps->ps_freebsd4, sig); 411 #endif 412 #ifdef COMPAT_43 413 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 414 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 415 (flags & KSA_OSIGSET) == 0) 416 SIGDELSET(ps->ps_osigset, sig); 417 else 418 SIGADDSET(ps->ps_osigset, sig); 419 #endif 420 } 421 mtx_unlock(&ps->ps_mtx); 422 PROC_UNLOCK(p); 423 return (0); 424 } 425 426 #ifndef _SYS_SYSPROTO_H_ 427 struct sigaction_args { 428 int sig; 429 struct sigaction *act; 430 struct sigaction *oact; 431 }; 432 #endif 433 /* 434 * MPSAFE 435 */ 436 int 437 sigaction(td, uap) 438 struct thread *td; 439 register struct sigaction_args *uap; 440 { 441 struct sigaction act, oact; 442 register struct sigaction *actp, *oactp; 443 int error; 444 445 actp = (uap->act != NULL) ? &act : NULL; 446 oactp = (uap->oact != NULL) ? &oact : NULL; 447 if (actp) { 448 error = copyin(uap->act, actp, sizeof(act)); 449 if (error) 450 return (error); 451 } 452 error = kern_sigaction(td, uap->sig, actp, oactp, 0); 453 if (oactp && !error) 454 error = copyout(oactp, uap->oact, sizeof(oact)); 455 return (error); 456 } 457 458 #ifdef COMPAT_FREEBSD4 459 #ifndef _SYS_SYSPROTO_H_ 460 struct freebsd4_sigaction_args { 461 int sig; 462 struct sigaction *act; 463 struct sigaction *oact; 464 }; 465 #endif 466 /* 467 * MPSAFE 468 */ 469 int 470 freebsd4_sigaction(td, uap) 471 struct thread *td; 472 register struct freebsd4_sigaction_args *uap; 473 { 474 struct sigaction act, oact; 475 register struct sigaction *actp, *oactp; 476 int error; 477 478 479 actp = (uap->act != NULL) ? &act : NULL; 480 oactp = (uap->oact != NULL) ? &oact : NULL; 481 if (actp) { 482 error = copyin(uap->act, actp, sizeof(act)); 483 if (error) 484 return (error); 485 } 486 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4); 487 if (oactp && !error) 488 error = copyout(oactp, uap->oact, sizeof(oact)); 489 return (error); 490 } 491 #endif /* COMAPT_FREEBSD4 */ 492 493 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 494 #ifndef _SYS_SYSPROTO_H_ 495 struct osigaction_args { 496 int signum; 497 struct osigaction *nsa; 498 struct osigaction *osa; 499 }; 500 #endif 501 /* 502 * MPSAFE 503 */ 504 int 505 osigaction(td, uap) 506 struct thread *td; 507 register struct osigaction_args *uap; 508 { 509 struct osigaction sa; 510 struct sigaction nsa, osa; 511 register struct sigaction *nsap, *osap; 512 int error; 513 514 if (uap->signum <= 0 || uap->signum >= ONSIG) 515 return (EINVAL); 516 517 nsap = (uap->nsa != NULL) ? &nsa : NULL; 518 osap = (uap->osa != NULL) ? &osa : NULL; 519 520 if (nsap) { 521 error = copyin(uap->nsa, &sa, sizeof(sa)); 522 if (error) 523 return (error); 524 nsap->sa_handler = sa.sa_handler; 525 nsap->sa_flags = sa.sa_flags; 526 OSIG2SIG(sa.sa_mask, nsap->sa_mask); 527 } 528 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 529 if (osap && !error) { 530 sa.sa_handler = osap->sa_handler; 531 sa.sa_flags = osap->sa_flags; 532 SIG2OSIG(osap->sa_mask, sa.sa_mask); 533 error = copyout(&sa, uap->osa, sizeof(sa)); 534 } 535 return (error); 536 } 537 538 #if !defined(__i386__) && !defined(__alpha__) 539 /* Avoid replicating the same stub everywhere */ 540 int 541 osigreturn(td, uap) 542 struct thread *td; 543 struct osigreturn_args *uap; 544 { 545 546 return (nosys(td, (struct nosys_args *)uap)); 547 } 548 #endif 549 #endif /* COMPAT_43 */ 550 551 /* 552 * Initialize signal state for process 0; 553 * set to ignore signals that are ignored by default. 554 */ 555 void 556 siginit(p) 557 struct proc *p; 558 { 559 register int i; 560 struct sigacts *ps; 561 562 PROC_LOCK(p); 563 ps = p->p_sigacts; 564 mtx_lock(&ps->ps_mtx); 565 for (i = 1; i <= NSIG; i++) 566 if (sigprop(i) & SA_IGNORE && i != SIGCONT) 567 SIGADDSET(ps->ps_sigignore, i); 568 mtx_unlock(&ps->ps_mtx); 569 PROC_UNLOCK(p); 570 } 571 572 /* 573 * Reset signals for an exec of the specified process. 574 */ 575 void 576 execsigs(struct proc *p) 577 { 578 struct sigacts *ps; 579 int sig; 580 struct thread *td; 581 582 /* 583 * Reset caught signals. Held signals remain held 584 * through td_sigmask (unless they were caught, 585 * and are now ignored by default). 586 */ 587 PROC_LOCK_ASSERT(p, MA_OWNED); 588 td = FIRST_THREAD_IN_PROC(p); 589 ps = p->p_sigacts; 590 mtx_lock(&ps->ps_mtx); 591 while (SIGNOTEMPTY(ps->ps_sigcatch)) { 592 sig = sig_ffs(&ps->ps_sigcatch); 593 SIGDELSET(ps->ps_sigcatch, sig); 594 if (sigprop(sig) & SA_IGNORE) { 595 if (sig != SIGCONT) 596 SIGADDSET(ps->ps_sigignore, sig); 597 SIGDELSET(p->p_siglist, sig); 598 /* 599 * There is only one thread at this point. 600 */ 601 SIGDELSET(td->td_siglist, sig); 602 } 603 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 604 } 605 /* 606 * Reset stack state to the user stack. 607 * Clear set of signals caught on the signal stack. 608 */ 609 td->td_sigstk.ss_flags = SS_DISABLE; 610 td->td_sigstk.ss_size = 0; 611 td->td_sigstk.ss_sp = 0; 612 td->td_pflags &= ~TDP_ALTSTACK; 613 /* 614 * Reset no zombies if child dies flag as Solaris does. 615 */ 616 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN); 617 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 618 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL; 619 mtx_unlock(&ps->ps_mtx); 620 } 621 622 /* 623 * kern_sigprocmask() 624 * 625 * Manipulate signal mask. 626 */ 627 int 628 kern_sigprocmask(td, how, set, oset, old) 629 struct thread *td; 630 int how; 631 sigset_t *set, *oset; 632 int old; 633 { 634 int error; 635 636 PROC_LOCK(td->td_proc); 637 if (oset != NULL) 638 *oset = td->td_sigmask; 639 640 error = 0; 641 if (set != NULL) { 642 switch (how) { 643 case SIG_BLOCK: 644 SIG_CANTMASK(*set); 645 SIGSETOR(td->td_sigmask, *set); 646 break; 647 case SIG_UNBLOCK: 648 SIGSETNAND(td->td_sigmask, *set); 649 signotify(td); 650 break; 651 case SIG_SETMASK: 652 SIG_CANTMASK(*set); 653 if (old) 654 SIGSETLO(td->td_sigmask, *set); 655 else 656 td->td_sigmask = *set; 657 signotify(td); 658 break; 659 default: 660 error = EINVAL; 661 break; 662 } 663 } 664 PROC_UNLOCK(td->td_proc); 665 return (error); 666 } 667 668 /* 669 * sigprocmask() - MP SAFE 670 */ 671 672 #ifndef _SYS_SYSPROTO_H_ 673 struct sigprocmask_args { 674 int how; 675 const sigset_t *set; 676 sigset_t *oset; 677 }; 678 #endif 679 int 680 sigprocmask(td, uap) 681 register struct thread *td; 682 struct sigprocmask_args *uap; 683 { 684 sigset_t set, oset; 685 sigset_t *setp, *osetp; 686 int error; 687 688 setp = (uap->set != NULL) ? &set : NULL; 689 osetp = (uap->oset != NULL) ? &oset : NULL; 690 if (setp) { 691 error = copyin(uap->set, setp, sizeof(set)); 692 if (error) 693 return (error); 694 } 695 error = kern_sigprocmask(td, uap->how, setp, osetp, 0); 696 if (osetp && !error) { 697 error = copyout(osetp, uap->oset, sizeof(oset)); 698 } 699 return (error); 700 } 701 702 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 703 /* 704 * osigprocmask() - MP SAFE 705 */ 706 #ifndef _SYS_SYSPROTO_H_ 707 struct osigprocmask_args { 708 int how; 709 osigset_t mask; 710 }; 711 #endif 712 int 713 osigprocmask(td, uap) 714 register struct thread *td; 715 struct osigprocmask_args *uap; 716 { 717 sigset_t set, oset; 718 int error; 719 720 OSIG2SIG(uap->mask, set); 721 error = kern_sigprocmask(td, uap->how, &set, &oset, 1); 722 SIG2OSIG(oset, td->td_retval[0]); 723 return (error); 724 } 725 #endif /* COMPAT_43 */ 726 727 #ifndef _SYS_SYSPROTO_H_ 728 struct sigpending_args { 729 sigset_t *set; 730 }; 731 #endif 732 /* 733 * MPSAFE 734 */ 735 int 736 sigwait(struct thread *td, struct sigwait_args *uap) 737 { 738 siginfo_t info; 739 sigset_t set; 740 int error; 741 742 error = copyin(uap->set, &set, sizeof(set)); 743 if (error) { 744 td->td_retval[0] = error; 745 return (0); 746 } 747 748 error = kern_sigtimedwait(td, set, &info, NULL); 749 if (error) { 750 if (error == ERESTART) 751 return (error); 752 td->td_retval[0] = error; 753 return (0); 754 } 755 756 error = copyout(&info.si_signo, uap->sig, sizeof(info.si_signo)); 757 /* Repost if we got an error. */ 758 if (error && info.si_signo) { 759 PROC_LOCK(td->td_proc); 760 tdsignal(td, info.si_signo, SIGTARGET_TD); 761 PROC_UNLOCK(td->td_proc); 762 } 763 td->td_retval[0] = error; 764 return (0); 765 } 766 /* 767 * MPSAFE 768 */ 769 int 770 sigtimedwait(struct thread *td, struct sigtimedwait_args *uap) 771 { 772 struct timespec ts; 773 struct timespec *timeout; 774 sigset_t set; 775 siginfo_t info; 776 int error; 777 778 if (uap->timeout) { 779 error = copyin(uap->timeout, &ts, sizeof(ts)); 780 if (error) 781 return (error); 782 783 timeout = &ts; 784 } else 785 timeout = NULL; 786 787 error = copyin(uap->set, &set, sizeof(set)); 788 if (error) 789 return (error); 790 791 error = kern_sigtimedwait(td, set, &info, timeout); 792 if (error) 793 return (error); 794 795 if (uap->info) 796 error = copyout(&info, uap->info, sizeof(info)); 797 /* Repost if we got an error. */ 798 if (error && info.si_signo) { 799 PROC_LOCK(td->td_proc); 800 tdsignal(td, info.si_signo, SIGTARGET_TD); 801 PROC_UNLOCK(td->td_proc); 802 } else { 803 td->td_retval[0] = info.si_signo; 804 } 805 return (error); 806 } 807 808 /* 809 * MPSAFE 810 */ 811 int 812 sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap) 813 { 814 siginfo_t info; 815 sigset_t set; 816 int error; 817 818 error = copyin(uap->set, &set, sizeof(set)); 819 if (error) 820 return (error); 821 822 error = kern_sigtimedwait(td, set, &info, NULL); 823 if (error) 824 return (error); 825 826 if (uap->info) 827 error = copyout(&info, uap->info, sizeof(info)); 828 /* Repost if we got an error. */ 829 if (error && info.si_signo) { 830 PROC_LOCK(td->td_proc); 831 tdsignal(td, info.si_signo, SIGTARGET_TD); 832 PROC_UNLOCK(td->td_proc); 833 } else { 834 td->td_retval[0] = info.si_signo; 835 } 836 return (error); 837 } 838 839 static int 840 kern_sigtimedwait(struct thread *td, sigset_t waitset, siginfo_t *info, 841 struct timespec *timeout) 842 { 843 struct sigacts *ps; 844 sigset_t savedmask, sigset; 845 struct proc *p; 846 int error; 847 int sig; 848 int hz; 849 int i; 850 851 p = td->td_proc; 852 error = 0; 853 sig = 0; 854 SIG_CANTMASK(waitset); 855 856 PROC_LOCK(p); 857 ps = p->p_sigacts; 858 savedmask = td->td_sigmask; 859 860 again: 861 for (i = 1; i <= _SIG_MAXSIG; ++i) { 862 if (!SIGISMEMBER(waitset, i)) 863 continue; 864 if (SIGISMEMBER(td->td_siglist, i)) { 865 SIGFILLSET(td->td_sigmask); 866 SIG_CANTMASK(td->td_sigmask); 867 SIGDELSET(td->td_sigmask, i); 868 mtx_lock(&ps->ps_mtx); 869 sig = cursig(td); 870 i = 0; 871 mtx_unlock(&ps->ps_mtx); 872 } else if (SIGISMEMBER(p->p_siglist, i)) { 873 if (p->p_flag & P_SA) { 874 p->p_flag |= P_SIGEVENT; 875 wakeup(&p->p_siglist); 876 } 877 SIGDELSET(p->p_siglist, i); 878 SIGADDSET(td->td_siglist, i); 879 SIGFILLSET(td->td_sigmask); 880 SIG_CANTMASK(td->td_sigmask); 881 SIGDELSET(td->td_sigmask, i); 882 mtx_lock(&ps->ps_mtx); 883 sig = cursig(td); 884 i = 0; 885 mtx_unlock(&ps->ps_mtx); 886 } 887 if (sig) { 888 td->td_sigmask = savedmask; 889 signotify(td); 890 goto out; 891 } 892 } 893 if (error) 894 goto out; 895 896 td->td_sigmask = savedmask; 897 signotify(td); 898 sigset = td->td_siglist; 899 SIGSETOR(sigset, p->p_siglist); 900 SIGSETAND(sigset, waitset); 901 if (!SIGISEMPTY(sigset)) 902 goto again; 903 904 /* 905 * POSIX says this must be checked after looking for pending 906 * signals. 907 */ 908 if (timeout) { 909 struct timeval tv; 910 911 if (timeout->tv_nsec < 0 || timeout->tv_nsec > 1000000000) { 912 error = EINVAL; 913 goto out; 914 } 915 if (timeout->tv_sec == 0 && timeout->tv_nsec == 0) { 916 error = EAGAIN; 917 goto out; 918 } 919 TIMESPEC_TO_TIMEVAL(&tv, timeout); 920 hz = tvtohz(&tv); 921 } else 922 hz = 0; 923 924 td->td_waitset = &waitset; 925 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz); 926 td->td_waitset = NULL; 927 if (error == 0) /* surplus wakeup ? */ 928 error = EINTR; 929 goto again; 930 931 out: 932 if (sig) { 933 sig_t action; 934 935 error = 0; 936 mtx_lock(&ps->ps_mtx); 937 action = ps->ps_sigact[_SIG_IDX(sig)]; 938 mtx_unlock(&ps->ps_mtx); 939 #ifdef KTRACE 940 if (KTRPOINT(td, KTR_PSIG)) 941 ktrpsig(sig, action, &td->td_sigmask, 0); 942 #endif 943 _STOPEVENT(p, S_SIG, sig); 944 945 SIGDELSET(td->td_siglist, sig); 946 info->si_signo = sig; 947 info->si_code = 0; 948 } 949 PROC_UNLOCK(p); 950 return (error); 951 } 952 953 /* 954 * MPSAFE 955 */ 956 int 957 sigpending(td, uap) 958 struct thread *td; 959 struct sigpending_args *uap; 960 { 961 struct proc *p = td->td_proc; 962 sigset_t siglist; 963 964 PROC_LOCK(p); 965 siglist = p->p_siglist; 966 SIGSETOR(siglist, td->td_siglist); 967 PROC_UNLOCK(p); 968 return (copyout(&siglist, uap->set, sizeof(sigset_t))); 969 } 970 971 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 972 #ifndef _SYS_SYSPROTO_H_ 973 struct osigpending_args { 974 int dummy; 975 }; 976 #endif 977 /* 978 * MPSAFE 979 */ 980 int 981 osigpending(td, uap) 982 struct thread *td; 983 struct osigpending_args *uap; 984 { 985 struct proc *p = td->td_proc; 986 sigset_t siglist; 987 988 PROC_LOCK(p); 989 siglist = p->p_siglist; 990 SIGSETOR(siglist, td->td_siglist); 991 PROC_UNLOCK(p); 992 SIG2OSIG(siglist, td->td_retval[0]); 993 return (0); 994 } 995 #endif /* COMPAT_43 */ 996 997 #if defined(COMPAT_43) 998 /* 999 * Generalized interface signal handler, 4.3-compatible. 1000 */ 1001 #ifndef _SYS_SYSPROTO_H_ 1002 struct osigvec_args { 1003 int signum; 1004 struct sigvec *nsv; 1005 struct sigvec *osv; 1006 }; 1007 #endif 1008 /* 1009 * MPSAFE 1010 */ 1011 /* ARGSUSED */ 1012 int 1013 osigvec(td, uap) 1014 struct thread *td; 1015 register struct osigvec_args *uap; 1016 { 1017 struct sigvec vec; 1018 struct sigaction nsa, osa; 1019 register struct sigaction *nsap, *osap; 1020 int error; 1021 1022 if (uap->signum <= 0 || uap->signum >= ONSIG) 1023 return (EINVAL); 1024 nsap = (uap->nsv != NULL) ? &nsa : NULL; 1025 osap = (uap->osv != NULL) ? &osa : NULL; 1026 if (nsap) { 1027 error = copyin(uap->nsv, &vec, sizeof(vec)); 1028 if (error) 1029 return (error); 1030 nsap->sa_handler = vec.sv_handler; 1031 OSIG2SIG(vec.sv_mask, nsap->sa_mask); 1032 nsap->sa_flags = vec.sv_flags; 1033 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */ 1034 } 1035 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 1036 if (osap && !error) { 1037 vec.sv_handler = osap->sa_handler; 1038 SIG2OSIG(osap->sa_mask, vec.sv_mask); 1039 vec.sv_flags = osap->sa_flags; 1040 vec.sv_flags &= ~SA_NOCLDWAIT; 1041 vec.sv_flags ^= SA_RESTART; 1042 error = copyout(&vec, uap->osv, sizeof(vec)); 1043 } 1044 return (error); 1045 } 1046 1047 #ifndef _SYS_SYSPROTO_H_ 1048 struct osigblock_args { 1049 int mask; 1050 }; 1051 #endif 1052 /* 1053 * MPSAFE 1054 */ 1055 int 1056 osigblock(td, uap) 1057 register struct thread *td; 1058 struct osigblock_args *uap; 1059 { 1060 struct proc *p = td->td_proc; 1061 sigset_t set; 1062 1063 OSIG2SIG(uap->mask, set); 1064 SIG_CANTMASK(set); 1065 PROC_LOCK(p); 1066 SIG2OSIG(td->td_sigmask, td->td_retval[0]); 1067 SIGSETOR(td->td_sigmask, set); 1068 PROC_UNLOCK(p); 1069 return (0); 1070 } 1071 1072 #ifndef _SYS_SYSPROTO_H_ 1073 struct osigsetmask_args { 1074 int mask; 1075 }; 1076 #endif 1077 /* 1078 * MPSAFE 1079 */ 1080 int 1081 osigsetmask(td, uap) 1082 struct thread *td; 1083 struct osigsetmask_args *uap; 1084 { 1085 struct proc *p = td->td_proc; 1086 sigset_t set; 1087 1088 OSIG2SIG(uap->mask, set); 1089 SIG_CANTMASK(set); 1090 PROC_LOCK(p); 1091 SIG2OSIG(td->td_sigmask, td->td_retval[0]); 1092 SIGSETLO(td->td_sigmask, set); 1093 signotify(td); 1094 PROC_UNLOCK(p); 1095 return (0); 1096 } 1097 #endif /* COMPAT_43 */ 1098 1099 /* 1100 * Suspend process until signal, providing mask to be set 1101 * in the meantime. 1102 ***** XXXKSE this doesn't make sense under KSE. 1103 ***** Do we suspend the thread or all threads in the process? 1104 ***** How do we suspend threads running NOW on another processor? 1105 */ 1106 #ifndef _SYS_SYSPROTO_H_ 1107 struct sigsuspend_args { 1108 const sigset_t *sigmask; 1109 }; 1110 #endif 1111 /* 1112 * MPSAFE 1113 */ 1114 /* ARGSUSED */ 1115 int 1116 sigsuspend(td, uap) 1117 struct thread *td; 1118 struct sigsuspend_args *uap; 1119 { 1120 sigset_t mask; 1121 int error; 1122 1123 error = copyin(uap->sigmask, &mask, sizeof(mask)); 1124 if (error) 1125 return (error); 1126 return (kern_sigsuspend(td, mask)); 1127 } 1128 1129 int 1130 kern_sigsuspend(struct thread *td, sigset_t mask) 1131 { 1132 struct proc *p = td->td_proc; 1133 1134 /* 1135 * When returning from sigsuspend, we want 1136 * the old mask to be restored after the 1137 * signal handler has finished. Thus, we 1138 * save it here and mark the sigacts structure 1139 * to indicate this. 1140 */ 1141 PROC_LOCK(p); 1142 td->td_oldsigmask = td->td_sigmask; 1143 td->td_pflags |= TDP_OLDMASK; 1144 SIG_CANTMASK(mask); 1145 td->td_sigmask = mask; 1146 signotify(td); 1147 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0) 1148 /* void */; 1149 PROC_UNLOCK(p); 1150 /* always return EINTR rather than ERESTART... */ 1151 return (EINTR); 1152 } 1153 1154 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 1155 /* 1156 * Compatibility sigsuspend call for old binaries. Note nonstandard calling 1157 * convention: libc stub passes mask, not pointer, to save a copyin. 1158 */ 1159 #ifndef _SYS_SYSPROTO_H_ 1160 struct osigsuspend_args { 1161 osigset_t mask; 1162 }; 1163 #endif 1164 /* 1165 * MPSAFE 1166 */ 1167 /* ARGSUSED */ 1168 int 1169 osigsuspend(td, uap) 1170 struct thread *td; 1171 struct osigsuspend_args *uap; 1172 { 1173 struct proc *p = td->td_proc; 1174 sigset_t mask; 1175 1176 PROC_LOCK(p); 1177 td->td_oldsigmask = td->td_sigmask; 1178 td->td_pflags |= TDP_OLDMASK; 1179 OSIG2SIG(uap->mask, mask); 1180 SIG_CANTMASK(mask); 1181 SIGSETLO(td->td_sigmask, mask); 1182 signotify(td); 1183 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0) 1184 /* void */; 1185 PROC_UNLOCK(p); 1186 /* always return EINTR rather than ERESTART... */ 1187 return (EINTR); 1188 } 1189 #endif /* COMPAT_43 */ 1190 1191 #if defined(COMPAT_43) 1192 #ifndef _SYS_SYSPROTO_H_ 1193 struct osigstack_args { 1194 struct sigstack *nss; 1195 struct sigstack *oss; 1196 }; 1197 #endif 1198 /* 1199 * MPSAFE 1200 */ 1201 /* ARGSUSED */ 1202 int 1203 osigstack(td, uap) 1204 struct thread *td; 1205 register struct osigstack_args *uap; 1206 { 1207 struct sigstack nss, oss; 1208 int error = 0; 1209 1210 if (uap->nss != NULL) { 1211 error = copyin(uap->nss, &nss, sizeof(nss)); 1212 if (error) 1213 return (error); 1214 } 1215 oss.ss_sp = td->td_sigstk.ss_sp; 1216 oss.ss_onstack = sigonstack(cpu_getstack(td)); 1217 if (uap->nss != NULL) { 1218 td->td_sigstk.ss_sp = nss.ss_sp; 1219 td->td_sigstk.ss_size = 0; 1220 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK; 1221 td->td_pflags |= TDP_ALTSTACK; 1222 } 1223 if (uap->oss != NULL) 1224 error = copyout(&oss, uap->oss, sizeof(oss)); 1225 1226 return (error); 1227 } 1228 #endif /* COMPAT_43 */ 1229 1230 #ifndef _SYS_SYSPROTO_H_ 1231 struct sigaltstack_args { 1232 stack_t *ss; 1233 stack_t *oss; 1234 }; 1235 #endif 1236 /* 1237 * MPSAFE 1238 */ 1239 /* ARGSUSED */ 1240 int 1241 sigaltstack(td, uap) 1242 struct thread *td; 1243 register struct sigaltstack_args *uap; 1244 { 1245 stack_t ss, oss; 1246 int error; 1247 1248 if (uap->ss != NULL) { 1249 error = copyin(uap->ss, &ss, sizeof(ss)); 1250 if (error) 1251 return (error); 1252 } 1253 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL, 1254 (uap->oss != NULL) ? &oss : NULL); 1255 if (error) 1256 return (error); 1257 if (uap->oss != NULL) 1258 error = copyout(&oss, uap->oss, sizeof(stack_t)); 1259 return (error); 1260 } 1261 1262 int 1263 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss) 1264 { 1265 struct proc *p = td->td_proc; 1266 int oonstack; 1267 1268 oonstack = sigonstack(cpu_getstack(td)); 1269 1270 if (oss != NULL) { 1271 *oss = td->td_sigstk; 1272 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK) 1273 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; 1274 } 1275 1276 if (ss != NULL) { 1277 if (oonstack) 1278 return (EPERM); 1279 if ((ss->ss_flags & ~SS_DISABLE) != 0) 1280 return (EINVAL); 1281 if (!(ss->ss_flags & SS_DISABLE)) { 1282 if (ss->ss_size < p->p_sysent->sv_minsigstksz) { 1283 return (ENOMEM); 1284 } 1285 td->td_sigstk = *ss; 1286 td->td_pflags |= TDP_ALTSTACK; 1287 } else { 1288 td->td_pflags &= ~TDP_ALTSTACK; 1289 } 1290 } 1291 return (0); 1292 } 1293 1294 /* 1295 * Common code for kill process group/broadcast kill. 1296 * cp is calling process. 1297 */ 1298 static int 1299 killpg1(td, sig, pgid, all) 1300 register struct thread *td; 1301 int sig, pgid, all; 1302 { 1303 register struct proc *p; 1304 struct pgrp *pgrp; 1305 int nfound = 0; 1306 1307 if (all) { 1308 /* 1309 * broadcast 1310 */ 1311 sx_slock(&allproc_lock); 1312 LIST_FOREACH(p, &allproc, p_list) { 1313 PROC_LOCK(p); 1314 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || 1315 p == td->td_proc) { 1316 PROC_UNLOCK(p); 1317 continue; 1318 } 1319 if (p_cansignal(td, p, sig) == 0) { 1320 nfound++; 1321 if (sig) 1322 psignal(p, sig); 1323 } 1324 PROC_UNLOCK(p); 1325 } 1326 sx_sunlock(&allproc_lock); 1327 } else { 1328 sx_slock(&proctree_lock); 1329 if (pgid == 0) { 1330 /* 1331 * zero pgid means send to my process group. 1332 */ 1333 pgrp = td->td_proc->p_pgrp; 1334 PGRP_LOCK(pgrp); 1335 } else { 1336 pgrp = pgfind(pgid); 1337 if (pgrp == NULL) { 1338 sx_sunlock(&proctree_lock); 1339 return (ESRCH); 1340 } 1341 } 1342 sx_sunlock(&proctree_lock); 1343 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1344 PROC_LOCK(p); 1345 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM) { 1346 PROC_UNLOCK(p); 1347 continue; 1348 } 1349 if (p->p_state == PRS_ZOMBIE) { 1350 PROC_UNLOCK(p); 1351 continue; 1352 } 1353 if (p_cansignal(td, p, sig) == 0) { 1354 nfound++; 1355 if (sig) 1356 psignal(p, sig); 1357 } 1358 PROC_UNLOCK(p); 1359 } 1360 PGRP_UNLOCK(pgrp); 1361 } 1362 return (nfound ? 0 : ESRCH); 1363 } 1364 1365 #ifndef _SYS_SYSPROTO_H_ 1366 struct kill_args { 1367 int pid; 1368 int signum; 1369 }; 1370 #endif 1371 /* 1372 * MPSAFE 1373 */ 1374 /* ARGSUSED */ 1375 int 1376 kill(td, uap) 1377 register struct thread *td; 1378 register struct kill_args *uap; 1379 { 1380 register struct proc *p; 1381 int error; 1382 1383 if ((u_int)uap->signum > _SIG_MAXSIG) 1384 return (EINVAL); 1385 1386 if (uap->pid > 0) { 1387 /* kill single process */ 1388 if ((p = pfind(uap->pid)) == NULL) 1389 return (ESRCH); 1390 error = p_cansignal(td, p, uap->signum); 1391 if (error == 0 && uap->signum) 1392 psignal(p, uap->signum); 1393 PROC_UNLOCK(p); 1394 return (error); 1395 } 1396 switch (uap->pid) { 1397 case -1: /* broadcast signal */ 1398 return (killpg1(td, uap->signum, 0, 1)); 1399 case 0: /* signal own process group */ 1400 return (killpg1(td, uap->signum, 0, 0)); 1401 default: /* negative explicit process group */ 1402 return (killpg1(td, uap->signum, -uap->pid, 0)); 1403 } 1404 /* NOTREACHED */ 1405 } 1406 1407 #if defined(COMPAT_43) 1408 #ifndef _SYS_SYSPROTO_H_ 1409 struct okillpg_args { 1410 int pgid; 1411 int signum; 1412 }; 1413 #endif 1414 /* 1415 * MPSAFE 1416 */ 1417 /* ARGSUSED */ 1418 int 1419 okillpg(td, uap) 1420 struct thread *td; 1421 register struct okillpg_args *uap; 1422 { 1423 1424 if ((u_int)uap->signum > _SIG_MAXSIG) 1425 return (EINVAL); 1426 return (killpg1(td, uap->signum, uap->pgid, 0)); 1427 } 1428 #endif /* COMPAT_43 */ 1429 1430 /* 1431 * Send a signal to a process group. 1432 */ 1433 void 1434 gsignal(pgid, sig) 1435 int pgid, sig; 1436 { 1437 struct pgrp *pgrp; 1438 1439 if (pgid != 0) { 1440 sx_slock(&proctree_lock); 1441 pgrp = pgfind(pgid); 1442 sx_sunlock(&proctree_lock); 1443 if (pgrp != NULL) { 1444 pgsignal(pgrp, sig, 0); 1445 PGRP_UNLOCK(pgrp); 1446 } 1447 } 1448 } 1449 1450 /* 1451 * Send a signal to a process group. If checktty is 1, 1452 * limit to members which have a controlling terminal. 1453 */ 1454 void 1455 pgsignal(pgrp, sig, checkctty) 1456 struct pgrp *pgrp; 1457 int sig, checkctty; 1458 { 1459 register struct proc *p; 1460 1461 if (pgrp) { 1462 PGRP_LOCK_ASSERT(pgrp, MA_OWNED); 1463 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1464 PROC_LOCK(p); 1465 if (checkctty == 0 || p->p_flag & P_CONTROLT) 1466 psignal(p, sig); 1467 PROC_UNLOCK(p); 1468 } 1469 } 1470 } 1471 1472 /* 1473 * Send a signal caused by a trap to the current thread. 1474 * If it will be caught immediately, deliver it with correct code. 1475 * Otherwise, post it normally. 1476 * 1477 * MPSAFE 1478 */ 1479 void 1480 trapsignal(struct thread *td, int sig, u_long code) 1481 { 1482 struct sigacts *ps; 1483 struct proc *p; 1484 siginfo_t siginfo; 1485 int error; 1486 1487 p = td->td_proc; 1488 if (td->td_pflags & TDP_SA) { 1489 if (td->td_mailbox == NULL) 1490 thread_user_enter(p, td); 1491 PROC_LOCK(p); 1492 if (td->td_mailbox) { 1493 SIGDELSET(td->td_sigmask, sig); 1494 mtx_lock_spin(&sched_lock); 1495 /* 1496 * Force scheduling an upcall, so UTS has chance to 1497 * process the signal before thread runs again in 1498 * userland. 1499 */ 1500 if (td->td_upcall) 1501 td->td_upcall->ku_flags |= KUF_DOUPCALL; 1502 mtx_unlock_spin(&sched_lock); 1503 } else { 1504 /* UTS caused a sync signal */ 1505 p->p_code = code; /* XXX for core dump/debugger */ 1506 p->p_sig = sig; /* XXX to verify code */ 1507 sigexit(td, sig); 1508 } 1509 } else { 1510 PROC_LOCK(p); 1511 } 1512 ps = p->p_sigacts; 1513 mtx_lock(&ps->ps_mtx); 1514 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) && 1515 !SIGISMEMBER(td->td_sigmask, sig)) { 1516 p->p_stats->p_ru.ru_nsignals++; 1517 #ifdef KTRACE 1518 if (KTRPOINT(curthread, KTR_PSIG)) 1519 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)], 1520 &td->td_sigmask, code); 1521 #endif 1522 if (!(td->td_pflags & TDP_SA)) 1523 (*p->p_sysent->sv_sendsig)( 1524 ps->ps_sigact[_SIG_IDX(sig)], sig, 1525 &td->td_sigmask, code); 1526 else { 1527 cpu_thread_siginfo(sig, code, &siginfo); 1528 mtx_unlock(&ps->ps_mtx); 1529 PROC_UNLOCK(p); 1530 error = copyout(&siginfo, &td->td_mailbox->tm_syncsig, 1531 sizeof(siginfo)); 1532 PROC_LOCK(p); 1533 /* UTS memory corrupted */ 1534 if (error) 1535 sigexit(td, SIGILL); 1536 SIGADDSET(td->td_sigmask, sig); 1537 mtx_lock(&ps->ps_mtx); 1538 } 1539 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 1540 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 1541 SIGADDSET(td->td_sigmask, sig); 1542 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 1543 /* 1544 * See kern_sigaction() for origin of this code. 1545 */ 1546 SIGDELSET(ps->ps_sigcatch, sig); 1547 if (sig != SIGCONT && 1548 sigprop(sig) & SA_IGNORE) 1549 SIGADDSET(ps->ps_sigignore, sig); 1550 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 1551 } 1552 mtx_unlock(&ps->ps_mtx); 1553 } else { 1554 mtx_unlock(&ps->ps_mtx); 1555 p->p_code = code; /* XXX for core dump/debugger */ 1556 p->p_sig = sig; /* XXX to verify code */ 1557 tdsignal(td, sig, SIGTARGET_TD); 1558 } 1559 PROC_UNLOCK(p); 1560 } 1561 1562 static struct thread * 1563 sigtd(struct proc *p, int sig, int prop) 1564 { 1565 struct thread *td, *signal_td; 1566 1567 PROC_LOCK_ASSERT(p, MA_OWNED); 1568 1569 /* 1570 * First find a thread in sigwait state and signal belongs to 1571 * its wait set. POSIX's arguments is that speed of delivering signal 1572 * to sigwait thread is faster than delivering signal to user stack. 1573 * If we can not find sigwait thread, then find the first thread in 1574 * the proc that doesn't have this signal masked, an exception is 1575 * if current thread is sending signal to its process, and it does not 1576 * mask the signal, it should get the signal, this is another fast 1577 * way to deliver signal. 1578 */ 1579 signal_td = NULL; 1580 mtx_lock_spin(&sched_lock); 1581 FOREACH_THREAD_IN_PROC(p, td) { 1582 if (td->td_waitset != NULL && 1583 SIGISMEMBER(*(td->td_waitset), sig)) { 1584 mtx_unlock_spin(&sched_lock); 1585 return (td); 1586 } 1587 if (!SIGISMEMBER(td->td_sigmask, sig)) { 1588 if (td == curthread) 1589 signal_td = curthread; 1590 else if (signal_td == NULL) 1591 signal_td = td; 1592 } 1593 } 1594 if (signal_td == NULL) 1595 signal_td = FIRST_THREAD_IN_PROC(p); 1596 mtx_unlock_spin(&sched_lock); 1597 return (signal_td); 1598 } 1599 1600 /* 1601 * Send the signal to the process. If the signal has an action, the action 1602 * is usually performed by the target process rather than the caller; we add 1603 * the signal to the set of pending signals for the process. 1604 * 1605 * Exceptions: 1606 * o When a stop signal is sent to a sleeping process that takes the 1607 * default action, the process is stopped without awakening it. 1608 * o SIGCONT restarts stopped processes (or puts them back to sleep) 1609 * regardless of the signal action (eg, blocked or ignored). 1610 * 1611 * Other ignored signals are discarded immediately. 1612 * 1613 * MPSAFE 1614 */ 1615 void 1616 psignal(struct proc *p, int sig) 1617 { 1618 struct thread *td; 1619 int prop; 1620 1621 if (!_SIG_VALID(sig)) 1622 panic("psignal(): invalid signal"); 1623 1624 PROC_LOCK_ASSERT(p, MA_OWNED); 1625 prop = sigprop(sig); 1626 1627 /* 1628 * Find a thread to deliver the signal to. 1629 */ 1630 td = sigtd(p, sig, prop); 1631 1632 tdsignal(td, sig, SIGTARGET_P); 1633 } 1634 1635 /* 1636 * MPSAFE 1637 */ 1638 void 1639 tdsignal(struct thread *td, int sig, sigtarget_t target) 1640 { 1641 sigset_t saved; 1642 struct proc *p = td->td_proc; 1643 1644 if (p->p_flag & P_SA) 1645 saved = p->p_siglist; 1646 do_tdsignal(td, sig, target); 1647 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) { 1648 if (SIGSETEQ(saved, p->p_siglist)) 1649 return; 1650 else { 1651 /* pending set changed */ 1652 p->p_flag |= P_SIGEVENT; 1653 wakeup(&p->p_siglist); 1654 } 1655 } 1656 } 1657 1658 static void 1659 do_tdsignal(struct thread *td, int sig, sigtarget_t target) 1660 { 1661 struct proc *p; 1662 register sig_t action; 1663 sigset_t *siglist; 1664 struct thread *td0; 1665 register int prop; 1666 struct sigacts *ps; 1667 1668 if (!_SIG_VALID(sig)) 1669 panic("do_tdsignal(): invalid signal"); 1670 1671 p = td->td_proc; 1672 ps = p->p_sigacts; 1673 1674 PROC_LOCK_ASSERT(p, MA_OWNED); 1675 KNOTE(&p->p_klist, NOTE_SIGNAL | sig); 1676 1677 prop = sigprop(sig); 1678 1679 /* 1680 * If the signal is blocked and not destined for this thread, then 1681 * assign it to the process so that we can find it later in the first 1682 * thread that unblocks it. Otherwise, assign it to this thread now. 1683 */ 1684 if (target == SIGTARGET_TD) { 1685 siglist = &td->td_siglist; 1686 } else { 1687 if (!SIGISMEMBER(td->td_sigmask, sig)) 1688 siglist = &td->td_siglist; 1689 else if (td->td_waitset != NULL && 1690 SIGISMEMBER(*(td->td_waitset), sig)) 1691 siglist = &td->td_siglist; 1692 else 1693 siglist = &p->p_siglist; 1694 } 1695 1696 /* 1697 * If proc is traced, always give parent a chance; 1698 * if signal event is tracked by procfs, give *that* 1699 * a chance, as well. 1700 */ 1701 if ((p->p_flag & P_TRACED) || (p->p_stops & S_SIG)) { 1702 action = SIG_DFL; 1703 } else { 1704 /* 1705 * If the signal is being ignored, 1706 * then we forget about it immediately. 1707 * (Note: we don't set SIGCONT in ps_sigignore, 1708 * and if it is set to SIG_IGN, 1709 * action will be SIG_DFL here.) 1710 */ 1711 mtx_lock(&ps->ps_mtx); 1712 if (SIGISMEMBER(ps->ps_sigignore, sig) || 1713 (p->p_flag & P_WEXIT)) { 1714 mtx_unlock(&ps->ps_mtx); 1715 return; 1716 } 1717 if (((td->td_waitset == NULL) && 1718 SIGISMEMBER(td->td_sigmask, sig)) || 1719 ((td->td_waitset != NULL) && 1720 SIGISMEMBER(td->td_sigmask, sig) && 1721 !SIGISMEMBER(*(td->td_waitset), sig))) 1722 action = SIG_HOLD; 1723 else if (SIGISMEMBER(ps->ps_sigcatch, sig)) 1724 action = SIG_CATCH; 1725 else 1726 action = SIG_DFL; 1727 mtx_unlock(&ps->ps_mtx); 1728 } 1729 1730 if (prop & SA_CONT) { 1731 SIG_STOPSIGMASK(p->p_siglist); 1732 /* 1733 * XXX Should investigate leaving STOP and CONT sigs only in 1734 * the proc's siglist. 1735 */ 1736 mtx_lock_spin(&sched_lock); 1737 FOREACH_THREAD_IN_PROC(p, td0) 1738 SIG_STOPSIGMASK(td0->td_siglist); 1739 mtx_unlock_spin(&sched_lock); 1740 } 1741 1742 if (prop & SA_STOP) { 1743 /* 1744 * If sending a tty stop signal to a member of an orphaned 1745 * process group, discard the signal here if the action 1746 * is default; don't stop the process below if sleeping, 1747 * and don't clear any pending SIGCONT. 1748 */ 1749 if ((prop & SA_TTYSTOP) && 1750 (p->p_pgrp->pg_jobc == 0) && 1751 (action == SIG_DFL)) 1752 return; 1753 SIG_CONTSIGMASK(p->p_siglist); 1754 mtx_lock_spin(&sched_lock); 1755 FOREACH_THREAD_IN_PROC(p, td0) 1756 SIG_CONTSIGMASK(td0->td_siglist); 1757 mtx_unlock_spin(&sched_lock); 1758 p->p_flag &= ~P_CONTINUED; 1759 } 1760 1761 SIGADDSET(*siglist, sig); 1762 signotify(td); /* uses schedlock */ 1763 if (siglist == &td->td_siglist && (td->td_waitset != NULL) && 1764 action != SIG_HOLD) { 1765 td->td_waitset = NULL; 1766 } 1767 1768 /* 1769 * Defer further processing for signals which are held, 1770 * except that stopped processes must be continued by SIGCONT. 1771 */ 1772 if (action == SIG_HOLD && 1773 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG))) 1774 return; 1775 /* 1776 * Some signals have a process-wide effect and a per-thread 1777 * component. Most processing occurs when the process next 1778 * tries to cross the user boundary, however there are some 1779 * times when processing needs to be done immediatly, such as 1780 * waking up threads so that they can cross the user boundary. 1781 * We try do the per-process part here. 1782 */ 1783 if (P_SHOULDSTOP(p)) { 1784 /* 1785 * The process is in stopped mode. All the threads should be 1786 * either winding down or already on the suspended queue. 1787 */ 1788 if (p->p_flag & P_TRACED) { 1789 /* 1790 * The traced process is already stopped, 1791 * so no further action is necessary. 1792 * No signal can restart us. 1793 */ 1794 goto out; 1795 } 1796 1797 if (sig == SIGKILL) { 1798 /* 1799 * SIGKILL sets process running. 1800 * It will die elsewhere. 1801 * All threads must be restarted. 1802 */ 1803 p->p_flag &= ~P_STOPPED; 1804 goto runfast; 1805 } 1806 1807 if (prop & SA_CONT) { 1808 /* 1809 * If SIGCONT is default (or ignored), we continue the 1810 * process but don't leave the signal in siglist as 1811 * it has no further action. If SIGCONT is held, we 1812 * continue the process and leave the signal in 1813 * siglist. If the process catches SIGCONT, let it 1814 * handle the signal itself. If it isn't waiting on 1815 * an event, it goes back to run state. 1816 * Otherwise, process goes back to sleep state. 1817 */ 1818 p->p_flag &= ~P_STOPPED_SIG; 1819 p->p_flag |= P_CONTINUED; 1820 if (action == SIG_DFL) { 1821 SIGDELSET(*siglist, sig); 1822 } else if (action == SIG_CATCH) { 1823 /* 1824 * The process wants to catch it so it needs 1825 * to run at least one thread, but which one? 1826 * It would seem that the answer would be to 1827 * run an upcall in the next KSE to run, and 1828 * deliver the signal that way. In a NON KSE 1829 * process, we need to make sure that the 1830 * single thread is runnable asap. 1831 * XXXKSE for now however, make them all run. 1832 */ 1833 goto runfast; 1834 } 1835 /* 1836 * The signal is not ignored or caught. 1837 */ 1838 mtx_lock_spin(&sched_lock); 1839 thread_unsuspend(p); 1840 mtx_unlock_spin(&sched_lock); 1841 goto out; 1842 } 1843 1844 if (prop & SA_STOP) { 1845 /* 1846 * Already stopped, don't need to stop again 1847 * (If we did the shell could get confused). 1848 * Just make sure the signal STOP bit set. 1849 */ 1850 p->p_flag |= P_STOPPED_SIG; 1851 SIGDELSET(*siglist, sig); 1852 goto out; 1853 } 1854 1855 /* 1856 * All other kinds of signals: 1857 * If a thread is sleeping interruptibly, simulate a 1858 * wakeup so that when it is continued it will be made 1859 * runnable and can look at the signal. However, don't make 1860 * the PROCESS runnable, leave it stopped. 1861 * It may run a bit until it hits a thread_suspend_check(). 1862 */ 1863 mtx_lock_spin(&sched_lock); 1864 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR)) 1865 sleepq_abort(td); 1866 mtx_unlock_spin(&sched_lock); 1867 goto out; 1868 /* 1869 * Mutexes are short lived. Threads waiting on them will 1870 * hit thread_suspend_check() soon. 1871 */ 1872 } else if (p->p_state == PRS_NORMAL) { 1873 if ((p->p_flag & P_TRACED) || (action != SIG_DFL) || 1874 !(prop & SA_STOP)) { 1875 mtx_lock_spin(&sched_lock); 1876 tdsigwakeup(td, sig, action); 1877 mtx_unlock_spin(&sched_lock); 1878 goto out; 1879 } 1880 if (prop & SA_STOP) { 1881 if (p->p_flag & P_PPWAIT) 1882 goto out; 1883 p->p_flag |= P_STOPPED_SIG; 1884 p->p_xstat = sig; 1885 mtx_lock_spin(&sched_lock); 1886 FOREACH_THREAD_IN_PROC(p, td0) { 1887 if (TD_IS_SLEEPING(td0) && 1888 (td0->td_flags & TDF_SINTR) && 1889 !TD_IS_SUSPENDED(td0)) { 1890 thread_suspend_one(td0); 1891 } else if (td != td0) { 1892 td0->td_flags |= TDF_ASTPENDING; 1893 } 1894 } 1895 thread_stopped(p); 1896 if (p->p_numthreads == p->p_suspcount) { 1897 SIGDELSET(p->p_siglist, p->p_xstat); 1898 FOREACH_THREAD_IN_PROC(p, td0) 1899 SIGDELSET(td0->td_siglist, p->p_xstat); 1900 } 1901 mtx_unlock_spin(&sched_lock); 1902 goto out; 1903 } 1904 else 1905 goto runfast; 1906 /* NOTREACHED */ 1907 } else { 1908 /* Not in "NORMAL" state. discard the signal. */ 1909 SIGDELSET(*siglist, sig); 1910 goto out; 1911 } 1912 1913 /* 1914 * The process is not stopped so we need to apply the signal to all the 1915 * running threads. 1916 */ 1917 1918 runfast: 1919 mtx_lock_spin(&sched_lock); 1920 tdsigwakeup(td, sig, action); 1921 thread_unsuspend(p); 1922 mtx_unlock_spin(&sched_lock); 1923 out: 1924 /* If we jump here, sched_lock should not be owned. */ 1925 mtx_assert(&sched_lock, MA_NOTOWNED); 1926 } 1927 1928 /* 1929 * The force of a signal has been directed against a single 1930 * thread. We need to see what we can do about knocking it 1931 * out of any sleep it may be in etc. 1932 */ 1933 static void 1934 tdsigwakeup(struct thread *td, int sig, sig_t action) 1935 { 1936 struct proc *p = td->td_proc; 1937 register int prop; 1938 1939 PROC_LOCK_ASSERT(p, MA_OWNED); 1940 mtx_assert(&sched_lock, MA_OWNED); 1941 prop = sigprop(sig); 1942 1943 /* 1944 * Bring the priority of a thread up if we want it to get 1945 * killed in this lifetime. 1946 */ 1947 if (action == SIG_DFL && (prop & SA_KILL)) { 1948 if (td->td_priority > PUSER) 1949 td->td_priority = PUSER; 1950 } 1951 1952 if (TD_ON_SLEEPQ(td)) { 1953 /* 1954 * If thread is sleeping uninterruptibly 1955 * we can't interrupt the sleep... the signal will 1956 * be noticed when the process returns through 1957 * trap() or syscall(). 1958 */ 1959 if ((td->td_flags & TDF_SINTR) == 0) 1960 return; 1961 /* 1962 * Process is sleeping and traced. Make it runnable 1963 * so it can discover the signal in issignal() and stop 1964 * for its parent. 1965 */ 1966 if (p->p_flag & P_TRACED) { 1967 p->p_flag &= ~P_STOPPED_TRACE; 1968 } else { 1969 /* 1970 * If SIGCONT is default (or ignored) and process is 1971 * asleep, we are finished; the process should not 1972 * be awakened. 1973 */ 1974 if ((prop & SA_CONT) && action == SIG_DFL) { 1975 SIGDELSET(p->p_siglist, sig); 1976 /* 1977 * It may be on either list in this state. 1978 * Remove from both for now. 1979 */ 1980 SIGDELSET(td->td_siglist, sig); 1981 return; 1982 } 1983 1984 /* 1985 * Give low priority threads a better chance to run. 1986 */ 1987 if (td->td_priority > PUSER) 1988 td->td_priority = PUSER; 1989 } 1990 sleepq_abort(td); 1991 } else { 1992 /* 1993 * Other states do nothing with the signal immediately, 1994 * other than kicking ourselves if we are running. 1995 * It will either never be noticed, or noticed very soon. 1996 */ 1997 #ifdef SMP 1998 if (TD_IS_RUNNING(td) && td != curthread) 1999 forward_signal(td); 2000 #endif 2001 } 2002 } 2003 2004 void 2005 ptracestop(struct thread *td, int sig) 2006 { 2007 struct proc *p = td->td_proc; 2008 2009 PROC_LOCK_ASSERT(p, MA_OWNED); 2010 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2011 &p->p_mtx.mtx_object, "Stopping for traced signal"); 2012 2013 p->p_xstat = sig; 2014 PROC_LOCK(p->p_pptr); 2015 psignal(p->p_pptr, SIGCHLD); 2016 PROC_UNLOCK(p->p_pptr); 2017 stop(p); 2018 mtx_lock_spin(&sched_lock); 2019 thread_suspend_one(td); 2020 PROC_UNLOCK(p); 2021 DROP_GIANT(); 2022 mi_switch(SW_INVOL, NULL); 2023 mtx_unlock_spin(&sched_lock); 2024 PICKUP_GIANT(); 2025 } 2026 2027 /* 2028 * If the current process has received a signal (should be caught or cause 2029 * termination, should interrupt current syscall), return the signal number. 2030 * Stop signals with default action are processed immediately, then cleared; 2031 * they aren't returned. This is checked after each entry to the system for 2032 * a syscall or trap (though this can usually be done without calling issignal 2033 * by checking the pending signal masks in cursig.) The normal call 2034 * sequence is 2035 * 2036 * while (sig = cursig(curthread)) 2037 * postsig(sig); 2038 */ 2039 static int 2040 issignal(td) 2041 struct thread *td; 2042 { 2043 struct proc *p; 2044 struct sigacts *ps; 2045 sigset_t sigpending; 2046 int sig, prop; 2047 struct thread *td0; 2048 2049 p = td->td_proc; 2050 ps = p->p_sigacts; 2051 mtx_assert(&ps->ps_mtx, MA_OWNED); 2052 PROC_LOCK_ASSERT(p, MA_OWNED); 2053 for (;;) { 2054 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG); 2055 2056 sigpending = td->td_siglist; 2057 SIGSETNAND(sigpending, td->td_sigmask); 2058 2059 if (p->p_flag & P_PPWAIT) 2060 SIG_STOPSIGMASK(sigpending); 2061 if (SIGISEMPTY(sigpending)) /* no signal to send */ 2062 return (0); 2063 sig = sig_ffs(&sigpending); 2064 2065 if (p->p_stops & S_SIG) { 2066 mtx_unlock(&ps->ps_mtx); 2067 stopevent(p, S_SIG, sig); 2068 mtx_lock(&ps->ps_mtx); 2069 } 2070 2071 /* 2072 * We should see pending but ignored signals 2073 * only if P_TRACED was on when they were posted. 2074 */ 2075 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) { 2076 SIGDELSET(td->td_siglist, sig); 2077 continue; 2078 } 2079 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) { 2080 /* 2081 * If traced, always stop. 2082 */ 2083 mtx_unlock(&ps->ps_mtx); 2084 ptracestop(td, sig); 2085 PROC_LOCK(p); 2086 mtx_lock(&ps->ps_mtx); 2087 2088 /* 2089 * If parent wants us to take the signal, 2090 * then it will leave it in p->p_xstat; 2091 * otherwise we just look for signals again. 2092 */ 2093 SIGDELSET(td->td_siglist, sig); /* clear old signal */ 2094 sig = p->p_xstat; 2095 if (sig == 0) 2096 continue; 2097 2098 /* 2099 * If the traced bit got turned off, go back up 2100 * to the top to rescan signals. This ensures 2101 * that p_sig* and p_sigact are consistent. 2102 */ 2103 if ((p->p_flag & P_TRACED) == 0) 2104 continue; 2105 2106 /* 2107 * Put the new signal into td_siglist. If the 2108 * signal is being masked, look for other signals. 2109 */ 2110 SIGADDSET(td->td_siglist, sig); 2111 if (SIGISMEMBER(td->td_sigmask, sig)) 2112 continue; 2113 signotify(td); 2114 } 2115 2116 prop = sigprop(sig); 2117 2118 /* 2119 * Decide whether the signal should be returned. 2120 * Return the signal's number, or fall through 2121 * to clear it from the pending mask. 2122 */ 2123 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) { 2124 2125 case (intptr_t)SIG_DFL: 2126 /* 2127 * Don't take default actions on system processes. 2128 */ 2129 if (p->p_pid <= 1) { 2130 #ifdef DIAGNOSTIC 2131 /* 2132 * Are you sure you want to ignore SIGSEGV 2133 * in init? XXX 2134 */ 2135 printf("Process (pid %lu) got signal %d\n", 2136 (u_long)p->p_pid, sig); 2137 #endif 2138 break; /* == ignore */ 2139 } 2140 /* 2141 * If there is a pending stop signal to process 2142 * with default action, stop here, 2143 * then clear the signal. However, 2144 * if process is member of an orphaned 2145 * process group, ignore tty stop signals. 2146 */ 2147 if (prop & SA_STOP) { 2148 if (p->p_flag & P_TRACED || 2149 (p->p_pgrp->pg_jobc == 0 && 2150 prop & SA_TTYSTOP)) 2151 break; /* == ignore */ 2152 mtx_unlock(&ps->ps_mtx); 2153 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2154 &p->p_mtx.mtx_object, "Catching SIGSTOP"); 2155 p->p_flag |= P_STOPPED_SIG; 2156 p->p_xstat = sig; 2157 mtx_lock_spin(&sched_lock); 2158 FOREACH_THREAD_IN_PROC(p, td0) { 2159 if (TD_IS_SLEEPING(td0) && 2160 (td0->td_flags & TDF_SINTR) && 2161 !TD_IS_SUSPENDED(td0)) { 2162 thread_suspend_one(td0); 2163 } else if (td != td0) { 2164 td0->td_flags |= TDF_ASTPENDING; 2165 } 2166 } 2167 thread_stopped(p); 2168 thread_suspend_one(td); 2169 PROC_UNLOCK(p); 2170 DROP_GIANT(); 2171 mi_switch(SW_INVOL, NULL); 2172 mtx_unlock_spin(&sched_lock); 2173 PICKUP_GIANT(); 2174 PROC_LOCK(p); 2175 mtx_lock(&ps->ps_mtx); 2176 break; 2177 } else if (prop & SA_IGNORE) { 2178 /* 2179 * Except for SIGCONT, shouldn't get here. 2180 * Default action is to ignore; drop it. 2181 */ 2182 break; /* == ignore */ 2183 } else 2184 return (sig); 2185 /*NOTREACHED*/ 2186 2187 case (intptr_t)SIG_IGN: 2188 /* 2189 * Masking above should prevent us ever trying 2190 * to take action on an ignored signal other 2191 * than SIGCONT, unless process is traced. 2192 */ 2193 if ((prop & SA_CONT) == 0 && 2194 (p->p_flag & P_TRACED) == 0) 2195 printf("issignal\n"); 2196 break; /* == ignore */ 2197 2198 default: 2199 /* 2200 * This signal has an action, let 2201 * postsig() process it. 2202 */ 2203 return (sig); 2204 } 2205 SIGDELSET(td->td_siglist, sig); /* take the signal! */ 2206 } 2207 /* NOTREACHED */ 2208 } 2209 2210 /* 2211 * Put the argument process into the stopped state and notify the parent 2212 * via wakeup. Signals are handled elsewhere. The process must not be 2213 * on the run queue. Must be called with the proc p locked. 2214 */ 2215 static void 2216 stop(struct proc *p) 2217 { 2218 2219 PROC_LOCK_ASSERT(p, MA_OWNED); 2220 p->p_flag |= P_STOPPED_SIG; 2221 p->p_flag &= ~P_WAITED; 2222 wakeup(p->p_pptr); 2223 } 2224 2225 /* 2226 * MPSAFE 2227 */ 2228 void 2229 thread_stopped(struct proc *p) 2230 { 2231 struct proc *p1 = curthread->td_proc; 2232 struct sigacts *ps; 2233 int n; 2234 2235 PROC_LOCK_ASSERT(p, MA_OWNED); 2236 mtx_assert(&sched_lock, MA_OWNED); 2237 n = p->p_suspcount; 2238 if (p == p1) 2239 n++; 2240 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) { 2241 mtx_unlock_spin(&sched_lock); 2242 stop(p); 2243 PROC_LOCK(p->p_pptr); 2244 ps = p->p_pptr->p_sigacts; 2245 mtx_lock(&ps->ps_mtx); 2246 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) { 2247 mtx_unlock(&ps->ps_mtx); 2248 psignal(p->p_pptr, SIGCHLD); 2249 } else 2250 mtx_unlock(&ps->ps_mtx); 2251 PROC_UNLOCK(p->p_pptr); 2252 mtx_lock_spin(&sched_lock); 2253 } 2254 } 2255 2256 /* 2257 * Take the action for the specified signal 2258 * from the current set of pending signals. 2259 */ 2260 void 2261 postsig(sig) 2262 register int sig; 2263 { 2264 struct thread *td = curthread; 2265 register struct proc *p = td->td_proc; 2266 struct sigacts *ps; 2267 sig_t action; 2268 sigset_t returnmask; 2269 int code; 2270 2271 KASSERT(sig != 0, ("postsig")); 2272 2273 PROC_LOCK_ASSERT(p, MA_OWNED); 2274 ps = p->p_sigacts; 2275 mtx_assert(&ps->ps_mtx, MA_OWNED); 2276 SIGDELSET(td->td_siglist, sig); 2277 action = ps->ps_sigact[_SIG_IDX(sig)]; 2278 #ifdef KTRACE 2279 if (KTRPOINT(td, KTR_PSIG)) 2280 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ? 2281 &td->td_oldsigmask : &td->td_sigmask, 0); 2282 #endif 2283 if (p->p_stops & S_SIG) { 2284 mtx_unlock(&ps->ps_mtx); 2285 stopevent(p, S_SIG, sig); 2286 mtx_lock(&ps->ps_mtx); 2287 } 2288 2289 if (!(td->td_pflags & TDP_SA && td->td_mailbox) && 2290 action == SIG_DFL) { 2291 /* 2292 * Default action, where the default is to kill 2293 * the process. (Other cases were ignored above.) 2294 */ 2295 mtx_unlock(&ps->ps_mtx); 2296 sigexit(td, sig); 2297 /* NOTREACHED */ 2298 } else { 2299 if (td->td_pflags & TDP_SA && td->td_mailbox) { 2300 if (sig == SIGKILL) { 2301 mtx_unlock(&ps->ps_mtx); 2302 sigexit(td, sig); 2303 } 2304 } 2305 2306 /* 2307 * If we get here, the signal must be caught. 2308 */ 2309 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig), 2310 ("postsig action")); 2311 /* 2312 * Set the new mask value and also defer further 2313 * occurrences of this signal. 2314 * 2315 * Special case: user has done a sigsuspend. Here the 2316 * current mask is not of interest, but rather the 2317 * mask from before the sigsuspend is what we want 2318 * restored after the signal processing is completed. 2319 */ 2320 if (td->td_pflags & TDP_OLDMASK) { 2321 returnmask = td->td_oldsigmask; 2322 td->td_pflags &= ~TDP_OLDMASK; 2323 } else 2324 returnmask = td->td_sigmask; 2325 2326 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 2327 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 2328 SIGADDSET(td->td_sigmask, sig); 2329 2330 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 2331 /* 2332 * See kern_sigaction() for origin of this code. 2333 */ 2334 SIGDELSET(ps->ps_sigcatch, sig); 2335 if (sig != SIGCONT && 2336 sigprop(sig) & SA_IGNORE) 2337 SIGADDSET(ps->ps_sigignore, sig); 2338 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 2339 } 2340 p->p_stats->p_ru.ru_nsignals++; 2341 if (p->p_sig != sig) { 2342 code = 0; 2343 } else { 2344 code = p->p_code; 2345 p->p_code = 0; 2346 p->p_sig = 0; 2347 } 2348 if (td->td_pflags & TDP_SA && td->td_mailbox) 2349 thread_signal_add(curthread, sig); 2350 else 2351 (*p->p_sysent->sv_sendsig)(action, sig, 2352 &returnmask, code); 2353 } 2354 } 2355 2356 /* 2357 * Kill the current process for stated reason. 2358 */ 2359 void 2360 killproc(p, why) 2361 struct proc *p; 2362 char *why; 2363 { 2364 2365 PROC_LOCK_ASSERT(p, MA_OWNED); 2366 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", 2367 p, p->p_pid, p->p_comm); 2368 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm, 2369 p->p_ucred ? p->p_ucred->cr_uid : -1, why); 2370 psignal(p, SIGKILL); 2371 } 2372 2373 /* 2374 * Force the current process to exit with the specified signal, dumping core 2375 * if appropriate. We bypass the normal tests for masked and caught signals, 2376 * allowing unrecoverable failures to terminate the process without changing 2377 * signal state. Mark the accounting record with the signal termination. 2378 * If dumping core, save the signal number for the debugger. Calls exit and 2379 * does not return. 2380 * 2381 * MPSAFE 2382 */ 2383 void 2384 sigexit(td, sig) 2385 struct thread *td; 2386 int sig; 2387 { 2388 struct proc *p = td->td_proc; 2389 2390 PROC_LOCK_ASSERT(p, MA_OWNED); 2391 p->p_acflag |= AXSIG; 2392 if (sigprop(sig) & SA_CORE) { 2393 p->p_sig = sig; 2394 /* 2395 * Log signals which would cause core dumps 2396 * (Log as LOG_INFO to appease those who don't want 2397 * these messages.) 2398 * XXX : Todo, as well as euid, write out ruid too 2399 * Note that coredump() drops proc lock. 2400 */ 2401 if (coredump(td) == 0) 2402 sig |= WCOREFLAG; 2403 if (kern_logsigexit) 2404 log(LOG_INFO, 2405 "pid %d (%s), uid %d: exited on signal %d%s\n", 2406 p->p_pid, p->p_comm, 2407 td->td_ucred ? td->td_ucred->cr_uid : -1, 2408 sig &~ WCOREFLAG, 2409 sig & WCOREFLAG ? " (core dumped)" : ""); 2410 } else 2411 PROC_UNLOCK(p); 2412 exit1(td, W_EXITCODE(0, sig)); 2413 /* NOTREACHED */ 2414 } 2415 2416 static char corefilename[MAXPATHLEN+1] = {"%N.core"}; 2417 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename, 2418 sizeof(corefilename), "process corefile name format string"); 2419 2420 /* 2421 * expand_name(name, uid, pid) 2422 * Expand the name described in corefilename, using name, uid, and pid. 2423 * corefilename is a printf-like string, with three format specifiers: 2424 * %N name of process ("name") 2425 * %P process id (pid) 2426 * %U user id (uid) 2427 * For example, "%N.core" is the default; they can be disabled completely 2428 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P". 2429 * This is controlled by the sysctl variable kern.corefile (see above). 2430 */ 2431 2432 static char * 2433 expand_name(name, uid, pid) 2434 const char *name; 2435 uid_t uid; 2436 pid_t pid; 2437 { 2438 const char *format, *appendstr; 2439 char *temp; 2440 char buf[11]; /* Buffer for pid/uid -- max 4B */ 2441 size_t i, l, n; 2442 2443 format = corefilename; 2444 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO); 2445 if (temp == NULL) 2446 return (NULL); 2447 for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) { 2448 switch (format[i]) { 2449 case '%': /* Format character */ 2450 i++; 2451 switch (format[i]) { 2452 case '%': 2453 appendstr = "%"; 2454 break; 2455 case 'N': /* process name */ 2456 appendstr = name; 2457 break; 2458 case 'P': /* process id */ 2459 sprintf(buf, "%u", pid); 2460 appendstr = buf; 2461 break; 2462 case 'U': /* user id */ 2463 sprintf(buf, "%u", uid); 2464 appendstr = buf; 2465 break; 2466 default: 2467 appendstr = ""; 2468 log(LOG_ERR, 2469 "Unknown format character %c in `%s'\n", 2470 format[i], format); 2471 } 2472 l = strlen(appendstr); 2473 if ((n + l) >= MAXPATHLEN) 2474 goto toolong; 2475 memcpy(temp + n, appendstr, l); 2476 n += l; 2477 break; 2478 default: 2479 temp[n++] = format[i]; 2480 } 2481 } 2482 if (format[i] != '\0') 2483 goto toolong; 2484 return (temp); 2485 toolong: 2486 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too long\n", 2487 (long)pid, name, (u_long)uid); 2488 free(temp, M_TEMP); 2489 return (NULL); 2490 } 2491 2492 /* 2493 * Dump a process' core. The main routine does some 2494 * policy checking, and creates the name of the coredump; 2495 * then it passes on a vnode and a size limit to the process-specific 2496 * coredump routine if there is one; if there _is not_ one, it returns 2497 * ENOSYS; otherwise it returns the error from the process-specific routine. 2498 */ 2499 2500 static int 2501 coredump(struct thread *td) 2502 { 2503 struct proc *p = td->td_proc; 2504 register struct vnode *vp; 2505 register struct ucred *cred = td->td_ucred; 2506 struct flock lf; 2507 struct nameidata nd; 2508 struct vattr vattr; 2509 int error, error1, flags, locked; 2510 struct mount *mp; 2511 char *name; /* name of corefile */ 2512 off_t limit; 2513 2514 PROC_LOCK_ASSERT(p, MA_OWNED); 2515 _STOPEVENT(p, S_CORE, 0); 2516 2517 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) { 2518 PROC_UNLOCK(p); 2519 return (EFAULT); 2520 } 2521 2522 /* 2523 * Note that the bulk of limit checking is done after 2524 * the corefile is created. The exception is if the limit 2525 * for corefiles is 0, in which case we don't bother 2526 * creating the corefile at all. This layout means that 2527 * a corefile is truncated instead of not being created, 2528 * if it is larger than the limit. 2529 */ 2530 limit = (off_t)lim_cur(p, RLIMIT_CORE); 2531 PROC_UNLOCK(p); 2532 if (limit == 0) 2533 return (EFBIG); 2534 2535 mtx_lock(&Giant); 2536 restart: 2537 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid); 2538 if (name == NULL) { 2539 mtx_unlock(&Giant); 2540 return (EINVAL); 2541 } 2542 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); /* XXXKSE */ 2543 flags = O_CREAT | FWRITE | O_NOFOLLOW; 2544 error = vn_open(&nd, &flags, S_IRUSR | S_IWUSR, -1); 2545 free(name, M_TEMP); 2546 if (error) { 2547 mtx_unlock(&Giant); 2548 return (error); 2549 } 2550 NDFREE(&nd, NDF_ONLY_PNBUF); 2551 vp = nd.ni_vp; 2552 2553 /* Don't dump to non-regular files or files with links. */ 2554 if (vp->v_type != VREG || 2555 VOP_GETATTR(vp, &vattr, cred, td) || vattr.va_nlink != 1) { 2556 VOP_UNLOCK(vp, 0, td); 2557 error = EFAULT; 2558 goto out; 2559 } 2560 2561 VOP_UNLOCK(vp, 0, td); 2562 lf.l_whence = SEEK_SET; 2563 lf.l_start = 0; 2564 lf.l_len = 0; 2565 lf.l_type = F_WRLCK; 2566 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0); 2567 2568 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 2569 lf.l_type = F_UNLCK; 2570 if (locked) 2571 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2572 if ((error = vn_close(vp, FWRITE, cred, td)) != 0) 2573 return (error); 2574 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0) 2575 return (error); 2576 goto restart; 2577 } 2578 2579 VATTR_NULL(&vattr); 2580 vattr.va_size = 0; 2581 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 2582 VOP_LEASE(vp, td, cred, LEASE_WRITE); 2583 VOP_SETATTR(vp, &vattr, cred, td); 2584 VOP_UNLOCK(vp, 0, td); 2585 PROC_LOCK(p); 2586 p->p_acflag |= ACORE; 2587 PROC_UNLOCK(p); 2588 2589 error = p->p_sysent->sv_coredump ? 2590 p->p_sysent->sv_coredump(td, vp, limit) : 2591 ENOSYS; 2592 2593 if (locked) { 2594 lf.l_type = F_UNLCK; 2595 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2596 } 2597 vn_finished_write(mp); 2598 out: 2599 error1 = vn_close(vp, FWRITE, cred, td); 2600 mtx_unlock(&Giant); 2601 if (error == 0) 2602 error = error1; 2603 return (error); 2604 } 2605 2606 /* 2607 * Nonexistent system call-- signal process (may want to handle it). 2608 * Flag error in case process won't see signal immediately (blocked or ignored). 2609 */ 2610 #ifndef _SYS_SYSPROTO_H_ 2611 struct nosys_args { 2612 int dummy; 2613 }; 2614 #endif 2615 /* 2616 * MPSAFE 2617 */ 2618 /* ARGSUSED */ 2619 int 2620 nosys(td, args) 2621 struct thread *td; 2622 struct nosys_args *args; 2623 { 2624 struct proc *p = td->td_proc; 2625 2626 PROC_LOCK(p); 2627 psignal(p, SIGSYS); 2628 PROC_UNLOCK(p); 2629 return (ENOSYS); 2630 } 2631 2632 /* 2633 * Send a SIGIO or SIGURG signal to a process or process group using 2634 * stored credentials rather than those of the current process. 2635 */ 2636 void 2637 pgsigio(sigiop, sig, checkctty) 2638 struct sigio **sigiop; 2639 int sig, checkctty; 2640 { 2641 struct sigio *sigio; 2642 2643 SIGIO_LOCK(); 2644 sigio = *sigiop; 2645 if (sigio == NULL) { 2646 SIGIO_UNLOCK(); 2647 return; 2648 } 2649 if (sigio->sio_pgid > 0) { 2650 PROC_LOCK(sigio->sio_proc); 2651 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred)) 2652 psignal(sigio->sio_proc, sig); 2653 PROC_UNLOCK(sigio->sio_proc); 2654 } else if (sigio->sio_pgid < 0) { 2655 struct proc *p; 2656 2657 PGRP_LOCK(sigio->sio_pgrp); 2658 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) { 2659 PROC_LOCK(p); 2660 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) && 2661 (checkctty == 0 || (p->p_flag & P_CONTROLT))) 2662 psignal(p, sig); 2663 PROC_UNLOCK(p); 2664 } 2665 PGRP_UNLOCK(sigio->sio_pgrp); 2666 } 2667 SIGIO_UNLOCK(); 2668 } 2669 2670 static int 2671 filt_sigattach(struct knote *kn) 2672 { 2673 struct proc *p = curproc; 2674 2675 kn->kn_ptr.p_proc = p; 2676 kn->kn_flags |= EV_CLEAR; /* automatically set */ 2677 2678 PROC_LOCK(p); 2679 SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext); 2680 PROC_UNLOCK(p); 2681 2682 return (0); 2683 } 2684 2685 static void 2686 filt_sigdetach(struct knote *kn) 2687 { 2688 struct proc *p = kn->kn_ptr.p_proc; 2689 2690 PROC_LOCK(p); 2691 SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext); 2692 PROC_UNLOCK(p); 2693 } 2694 2695 /* 2696 * signal knotes are shared with proc knotes, so we apply a mask to 2697 * the hint in order to differentiate them from process hints. This 2698 * could be avoided by using a signal-specific knote list, but probably 2699 * isn't worth the trouble. 2700 */ 2701 static int 2702 filt_signal(struct knote *kn, long hint) 2703 { 2704 2705 if (hint & NOTE_SIGNAL) { 2706 hint &= ~NOTE_SIGNAL; 2707 2708 if (kn->kn_id == hint) 2709 kn->kn_data++; 2710 } 2711 return (kn->kn_data != 0); 2712 } 2713 2714 struct sigacts * 2715 sigacts_alloc(void) 2716 { 2717 struct sigacts *ps; 2718 2719 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO); 2720 ps->ps_refcnt = 1; 2721 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF); 2722 return (ps); 2723 } 2724 2725 void 2726 sigacts_free(struct sigacts *ps) 2727 { 2728 2729 mtx_lock(&ps->ps_mtx); 2730 ps->ps_refcnt--; 2731 if (ps->ps_refcnt == 0) { 2732 mtx_destroy(&ps->ps_mtx); 2733 free(ps, M_SUBPROC); 2734 } else 2735 mtx_unlock(&ps->ps_mtx); 2736 } 2737 2738 struct sigacts * 2739 sigacts_hold(struct sigacts *ps) 2740 { 2741 mtx_lock(&ps->ps_mtx); 2742 ps->ps_refcnt++; 2743 mtx_unlock(&ps->ps_mtx); 2744 return (ps); 2745 } 2746 2747 void 2748 sigacts_copy(struct sigacts *dest, struct sigacts *src) 2749 { 2750 2751 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest")); 2752 mtx_lock(&src->ps_mtx); 2753 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt)); 2754 mtx_unlock(&src->ps_mtx); 2755 } 2756 2757 int 2758 sigacts_shared(struct sigacts *ps) 2759 { 2760 int shared; 2761 2762 mtx_lock(&ps->ps_mtx); 2763 shared = ps->ps_refcnt > 1; 2764 mtx_unlock(&ps->ps_mtx); 2765 return (shared); 2766 } 2767