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) || defined(COMPAT_SUNOS) 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 #ifdef COMPAT_SUNOS 351 if (act->sa_flags & SA_USERTRAMP) 352 SIGADDSET(ps->ps_usertramp, sig); 353 else 354 SIGDELSET(ps->ps_usertramp, sig); 355 #endif 356 if (sig == SIGCHLD) { 357 if (act->sa_flags & SA_NOCLDSTOP) 358 ps->ps_flag |= PS_NOCLDSTOP; 359 else 360 ps->ps_flag &= ~PS_NOCLDSTOP; 361 if (act->sa_flags & SA_NOCLDWAIT) { 362 /* 363 * Paranoia: since SA_NOCLDWAIT is implemented 364 * by reparenting the dying child to PID 1 (and 365 * trust it to reap the zombie), PID 1 itself 366 * is forbidden to set SA_NOCLDWAIT. 367 */ 368 if (p->p_pid == 1) 369 ps->ps_flag &= ~PS_NOCLDWAIT; 370 else 371 ps->ps_flag |= PS_NOCLDWAIT; 372 } else 373 ps->ps_flag &= ~PS_NOCLDWAIT; 374 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 375 ps->ps_flag |= PS_CLDSIGIGN; 376 else 377 ps->ps_flag &= ~PS_CLDSIGIGN; 378 } 379 /* 380 * Set bit in ps_sigignore for signals that are set to SIG_IGN, 381 * and for signals set to SIG_DFL where the default is to 382 * ignore. However, don't put SIGCONT in ps_sigignore, as we 383 * have to restart the process. 384 */ 385 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 386 (sigprop(sig) & SA_IGNORE && 387 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) { 388 if ((p->p_flag & P_SA) && 389 SIGISMEMBER(p->p_siglist, sig)) { 390 p->p_flag |= P_SIGEVENT; 391 wakeup(&p->p_siglist); 392 } 393 /* never to be seen again */ 394 SIGDELSET(p->p_siglist, sig); 395 mtx_lock_spin(&sched_lock); 396 FOREACH_THREAD_IN_PROC(p, td0) 397 SIGDELSET(td0->td_siglist, sig); 398 mtx_unlock_spin(&sched_lock); 399 if (sig != SIGCONT) 400 /* easier in psignal */ 401 SIGADDSET(ps->ps_sigignore, sig); 402 SIGDELSET(ps->ps_sigcatch, sig); 403 } else { 404 SIGDELSET(ps->ps_sigignore, sig); 405 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL) 406 SIGDELSET(ps->ps_sigcatch, sig); 407 else 408 SIGADDSET(ps->ps_sigcatch, sig); 409 } 410 #ifdef COMPAT_FREEBSD4 411 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 412 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 413 (flags & KSA_FREEBSD4) == 0) 414 SIGDELSET(ps->ps_freebsd4, sig); 415 else 416 SIGADDSET(ps->ps_freebsd4, sig); 417 #endif 418 #ifdef COMPAT_43 419 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 420 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 421 (flags & KSA_OSIGSET) == 0) 422 SIGDELSET(ps->ps_osigset, sig); 423 else 424 SIGADDSET(ps->ps_osigset, sig); 425 #endif 426 } 427 mtx_unlock(&ps->ps_mtx); 428 PROC_UNLOCK(p); 429 return (0); 430 } 431 432 #ifndef _SYS_SYSPROTO_H_ 433 struct sigaction_args { 434 int sig; 435 struct sigaction *act; 436 struct sigaction *oact; 437 }; 438 #endif 439 /* 440 * MPSAFE 441 */ 442 int 443 sigaction(td, uap) 444 struct thread *td; 445 register struct sigaction_args *uap; 446 { 447 struct sigaction act, oact; 448 register struct sigaction *actp, *oactp; 449 int error; 450 451 actp = (uap->act != NULL) ? &act : NULL; 452 oactp = (uap->oact != NULL) ? &oact : NULL; 453 if (actp) { 454 error = copyin(uap->act, actp, sizeof(act)); 455 if (error) 456 return (error); 457 } 458 error = kern_sigaction(td, uap->sig, actp, oactp, 0); 459 if (oactp && !error) 460 error = copyout(oactp, uap->oact, sizeof(oact)); 461 return (error); 462 } 463 464 #ifdef COMPAT_FREEBSD4 465 #ifndef _SYS_SYSPROTO_H_ 466 struct freebsd4_sigaction_args { 467 int sig; 468 struct sigaction *act; 469 struct sigaction *oact; 470 }; 471 #endif 472 /* 473 * MPSAFE 474 */ 475 int 476 freebsd4_sigaction(td, uap) 477 struct thread *td; 478 register struct freebsd4_sigaction_args *uap; 479 { 480 struct sigaction act, oact; 481 register struct sigaction *actp, *oactp; 482 int error; 483 484 485 actp = (uap->act != NULL) ? &act : NULL; 486 oactp = (uap->oact != NULL) ? &oact : NULL; 487 if (actp) { 488 error = copyin(uap->act, actp, sizeof(act)); 489 if (error) 490 return (error); 491 } 492 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4); 493 if (oactp && !error) 494 error = copyout(oactp, uap->oact, sizeof(oact)); 495 return (error); 496 } 497 #endif /* COMAPT_FREEBSD4 */ 498 499 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 500 #ifndef _SYS_SYSPROTO_H_ 501 struct osigaction_args { 502 int signum; 503 struct osigaction *nsa; 504 struct osigaction *osa; 505 }; 506 #endif 507 /* 508 * MPSAFE 509 */ 510 int 511 osigaction(td, uap) 512 struct thread *td; 513 register struct osigaction_args *uap; 514 { 515 struct osigaction sa; 516 struct sigaction nsa, osa; 517 register struct sigaction *nsap, *osap; 518 int error; 519 520 if (uap->signum <= 0 || uap->signum >= ONSIG) 521 return (EINVAL); 522 523 nsap = (uap->nsa != NULL) ? &nsa : NULL; 524 osap = (uap->osa != NULL) ? &osa : NULL; 525 526 if (nsap) { 527 error = copyin(uap->nsa, &sa, sizeof(sa)); 528 if (error) 529 return (error); 530 nsap->sa_handler = sa.sa_handler; 531 nsap->sa_flags = sa.sa_flags; 532 OSIG2SIG(sa.sa_mask, nsap->sa_mask); 533 } 534 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 535 if (osap && !error) { 536 sa.sa_handler = osap->sa_handler; 537 sa.sa_flags = osap->sa_flags; 538 SIG2OSIG(osap->sa_mask, sa.sa_mask); 539 error = copyout(&sa, uap->osa, sizeof(sa)); 540 } 541 return (error); 542 } 543 544 #if !defined(__i386__) && !defined(__alpha__) 545 /* Avoid replicating the same stub everywhere */ 546 int 547 osigreturn(td, uap) 548 struct thread *td; 549 struct osigreturn_args *uap; 550 { 551 552 return (nosys(td, (struct nosys_args *)uap)); 553 } 554 #endif 555 #endif /* COMPAT_43 */ 556 557 /* 558 * Initialize signal state for process 0; 559 * set to ignore signals that are ignored by default. 560 */ 561 void 562 siginit(p) 563 struct proc *p; 564 { 565 register int i; 566 struct sigacts *ps; 567 568 PROC_LOCK(p); 569 ps = p->p_sigacts; 570 mtx_lock(&ps->ps_mtx); 571 for (i = 1; i <= NSIG; i++) 572 if (sigprop(i) & SA_IGNORE && i != SIGCONT) 573 SIGADDSET(ps->ps_sigignore, i); 574 mtx_unlock(&ps->ps_mtx); 575 PROC_UNLOCK(p); 576 } 577 578 /* 579 * Reset signals for an exec of the specified process. 580 */ 581 void 582 execsigs(struct proc *p) 583 { 584 struct sigacts *ps; 585 int sig; 586 struct thread *td; 587 588 /* 589 * Reset caught signals. Held signals remain held 590 * through td_sigmask (unless they were caught, 591 * and are now ignored by default). 592 */ 593 PROC_LOCK_ASSERT(p, MA_OWNED); 594 td = FIRST_THREAD_IN_PROC(p); 595 ps = p->p_sigacts; 596 mtx_lock(&ps->ps_mtx); 597 while (SIGNOTEMPTY(ps->ps_sigcatch)) { 598 sig = sig_ffs(&ps->ps_sigcatch); 599 SIGDELSET(ps->ps_sigcatch, sig); 600 if (sigprop(sig) & SA_IGNORE) { 601 if (sig != SIGCONT) 602 SIGADDSET(ps->ps_sigignore, sig); 603 SIGDELSET(p->p_siglist, sig); 604 /* 605 * There is only one thread at this point. 606 */ 607 SIGDELSET(td->td_siglist, sig); 608 } 609 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 610 } 611 /* 612 * Reset stack state to the user stack. 613 * Clear set of signals caught on the signal stack. 614 */ 615 td->td_sigstk.ss_flags = SS_DISABLE; 616 td->td_sigstk.ss_size = 0; 617 td->td_sigstk.ss_sp = 0; 618 td->td_pflags &= ~TDP_ALTSTACK; 619 /* 620 * Reset no zombies if child dies flag as Solaris does. 621 */ 622 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN); 623 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 624 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL; 625 mtx_unlock(&ps->ps_mtx); 626 } 627 628 /* 629 * kern_sigprocmask() 630 * 631 * Manipulate signal mask. 632 */ 633 int 634 kern_sigprocmask(td, how, set, oset, old) 635 struct thread *td; 636 int how; 637 sigset_t *set, *oset; 638 int old; 639 { 640 int error; 641 642 PROC_LOCK(td->td_proc); 643 if (oset != NULL) 644 *oset = td->td_sigmask; 645 646 error = 0; 647 if (set != NULL) { 648 switch (how) { 649 case SIG_BLOCK: 650 SIG_CANTMASK(*set); 651 SIGSETOR(td->td_sigmask, *set); 652 break; 653 case SIG_UNBLOCK: 654 SIGSETNAND(td->td_sigmask, *set); 655 signotify(td); 656 break; 657 case SIG_SETMASK: 658 SIG_CANTMASK(*set); 659 if (old) 660 SIGSETLO(td->td_sigmask, *set); 661 else 662 td->td_sigmask = *set; 663 signotify(td); 664 break; 665 default: 666 error = EINVAL; 667 break; 668 } 669 } 670 PROC_UNLOCK(td->td_proc); 671 return (error); 672 } 673 674 /* 675 * sigprocmask() - MP SAFE 676 */ 677 678 #ifndef _SYS_SYSPROTO_H_ 679 struct sigprocmask_args { 680 int how; 681 const sigset_t *set; 682 sigset_t *oset; 683 }; 684 #endif 685 int 686 sigprocmask(td, uap) 687 register struct thread *td; 688 struct sigprocmask_args *uap; 689 { 690 sigset_t set, oset; 691 sigset_t *setp, *osetp; 692 int error; 693 694 setp = (uap->set != NULL) ? &set : NULL; 695 osetp = (uap->oset != NULL) ? &oset : NULL; 696 if (setp) { 697 error = copyin(uap->set, setp, sizeof(set)); 698 if (error) 699 return (error); 700 } 701 error = kern_sigprocmask(td, uap->how, setp, osetp, 0); 702 if (osetp && !error) { 703 error = copyout(osetp, uap->oset, sizeof(oset)); 704 } 705 return (error); 706 } 707 708 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 709 /* 710 * osigprocmask() - MP SAFE 711 */ 712 #ifndef _SYS_SYSPROTO_H_ 713 struct osigprocmask_args { 714 int how; 715 osigset_t mask; 716 }; 717 #endif 718 int 719 osigprocmask(td, uap) 720 register struct thread *td; 721 struct osigprocmask_args *uap; 722 { 723 sigset_t set, oset; 724 int error; 725 726 OSIG2SIG(uap->mask, set); 727 error = kern_sigprocmask(td, uap->how, &set, &oset, 1); 728 SIG2OSIG(oset, td->td_retval[0]); 729 return (error); 730 } 731 #endif /* COMPAT_43 */ 732 733 #ifndef _SYS_SYSPROTO_H_ 734 struct sigpending_args { 735 sigset_t *set; 736 }; 737 #endif 738 /* 739 * MPSAFE 740 */ 741 int 742 sigwait(struct thread *td, struct sigwait_args *uap) 743 { 744 siginfo_t info; 745 sigset_t set; 746 int error; 747 748 error = copyin(uap->set, &set, sizeof(set)); 749 if (error) 750 return (error); 751 752 error = kern_sigtimedwait(td, set, &info, NULL); 753 if (error) 754 return (error); 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 return (error); 764 } 765 /* 766 * MPSAFE 767 */ 768 int 769 sigtimedwait(struct thread *td, struct sigtimedwait_args *uap) 770 { 771 struct timespec ts; 772 struct timespec *timeout; 773 sigset_t set; 774 siginfo_t info; 775 int error; 776 777 if (uap->timeout) { 778 error = copyin(uap->timeout, &ts, sizeof(ts)); 779 if (error) 780 return (error); 781 782 timeout = &ts; 783 } else 784 timeout = NULL; 785 786 error = copyin(uap->set, &set, sizeof(set)); 787 if (error) 788 return (error); 789 790 error = kern_sigtimedwait(td, set, &info, timeout); 791 if (error) 792 return (error); 793 794 if (uap->info) 795 error = copyout(&info, uap->info, sizeof(info)); 796 /* Repost if we got an error. */ 797 if (error && info.si_signo) { 798 PROC_LOCK(td->td_proc); 799 tdsignal(td, info.si_signo, SIGTARGET_TD); 800 PROC_UNLOCK(td->td_proc); 801 } else { 802 td->td_retval[0] = info.si_signo; 803 } 804 return (error); 805 } 806 807 /* 808 * MPSAFE 809 */ 810 int 811 sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap) 812 { 813 siginfo_t info; 814 sigset_t set; 815 int error; 816 817 error = copyin(uap->set, &set, sizeof(set)); 818 if (error) 819 return (error); 820 821 error = kern_sigtimedwait(td, set, &info, NULL); 822 if (error) 823 return (error); 824 825 if (uap->info) 826 error = copyout(&info, uap->info, sizeof(info)); 827 /* Repost if we got an error. */ 828 if (error && info.si_signo) { 829 PROC_LOCK(td->td_proc); 830 tdsignal(td, info.si_signo, SIGTARGET_TD); 831 PROC_UNLOCK(td->td_proc); 832 } else { 833 td->td_retval[0] = info.si_signo; 834 } 835 return (error); 836 } 837 838 static int 839 kern_sigtimedwait(struct thread *td, sigset_t waitset, siginfo_t *info, 840 struct timespec *timeout) 841 { 842 struct sigacts *ps; 843 sigset_t savedmask, sigset; 844 struct proc *p; 845 int error; 846 int sig; 847 int hz; 848 int i; 849 850 p = td->td_proc; 851 error = 0; 852 sig = 0; 853 SIG_CANTMASK(waitset); 854 855 PROC_LOCK(p); 856 ps = p->p_sigacts; 857 savedmask = td->td_sigmask; 858 859 again: 860 for (i = 1; i <= _SIG_MAXSIG; ++i) { 861 if (!SIGISMEMBER(waitset, i)) 862 continue; 863 if (SIGISMEMBER(td->td_siglist, i)) { 864 SIGFILLSET(td->td_sigmask); 865 SIG_CANTMASK(td->td_sigmask); 866 SIGDELSET(td->td_sigmask, i); 867 mtx_lock(&ps->ps_mtx); 868 sig = cursig(td); 869 i = 0; 870 mtx_unlock(&ps->ps_mtx); 871 } else if (SIGISMEMBER(p->p_siglist, i)) { 872 if (p->p_flag & P_SA) { 873 p->p_flag |= P_SIGEVENT; 874 wakeup(&p->p_siglist); 875 } 876 SIGDELSET(p->p_siglist, i); 877 SIGADDSET(td->td_siglist, i); 878 SIGFILLSET(td->td_sigmask); 879 SIG_CANTMASK(td->td_sigmask); 880 SIGDELSET(td->td_sigmask, i); 881 mtx_lock(&ps->ps_mtx); 882 sig = cursig(td); 883 i = 0; 884 mtx_unlock(&ps->ps_mtx); 885 } 886 if (sig) { 887 td->td_sigmask = savedmask; 888 signotify(td); 889 goto out; 890 } 891 } 892 if (error) 893 goto out; 894 895 td->td_sigmask = savedmask; 896 signotify(td); 897 sigset = td->td_siglist; 898 SIGSETOR(sigset, p->p_siglist); 899 SIGSETAND(sigset, waitset); 900 if (!SIGISEMPTY(sigset)) 901 goto again; 902 903 /* 904 * POSIX says this must be checked after looking for pending 905 * signals. 906 */ 907 if (timeout) { 908 struct timeval tv; 909 910 if (timeout->tv_nsec < 0 || timeout->tv_nsec > 1000000000) { 911 error = EINVAL; 912 goto out; 913 } 914 if (timeout->tv_sec == 0 && timeout->tv_nsec == 0) { 915 error = EAGAIN; 916 goto out; 917 } 918 TIMESPEC_TO_TIMEVAL(&tv, timeout); 919 hz = tvtohz(&tv); 920 } else 921 hz = 0; 922 923 td->td_waitset = &waitset; 924 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz); 925 td->td_waitset = NULL; 926 if (error == 0) /* surplus wakeup ? */ 927 error = EINTR; 928 goto again; 929 930 out: 931 if (sig) { 932 sig_t action; 933 934 error = 0; 935 mtx_lock(&ps->ps_mtx); 936 action = ps->ps_sigact[_SIG_IDX(sig)]; 937 mtx_unlock(&ps->ps_mtx); 938 #ifdef KTRACE 939 if (KTRPOINT(td, KTR_PSIG)) 940 ktrpsig(sig, action, &td->td_sigmask, 0); 941 #endif 942 _STOPEVENT(p, S_SIG, sig); 943 944 SIGDELSET(td->td_siglist, sig); 945 info->si_signo = sig; 946 info->si_code = 0; 947 } 948 PROC_UNLOCK(p); 949 return (error); 950 } 951 952 /* 953 * MPSAFE 954 */ 955 int 956 sigpending(td, uap) 957 struct thread *td; 958 struct sigpending_args *uap; 959 { 960 struct proc *p = td->td_proc; 961 sigset_t siglist; 962 963 PROC_LOCK(p); 964 siglist = p->p_siglist; 965 SIGSETOR(siglist, td->td_siglist); 966 PROC_UNLOCK(p); 967 return (copyout(&siglist, uap->set, sizeof(sigset_t))); 968 } 969 970 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 971 #ifndef _SYS_SYSPROTO_H_ 972 struct osigpending_args { 973 int dummy; 974 }; 975 #endif 976 /* 977 * MPSAFE 978 */ 979 int 980 osigpending(td, uap) 981 struct thread *td; 982 struct osigpending_args *uap; 983 { 984 struct proc *p = td->td_proc; 985 sigset_t siglist; 986 987 PROC_LOCK(p); 988 siglist = p->p_siglist; 989 SIGSETOR(siglist, td->td_siglist); 990 PROC_UNLOCK(p); 991 SIG2OSIG(siglist, td->td_retval[0]); 992 return (0); 993 } 994 #endif /* COMPAT_43 */ 995 996 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 997 /* 998 * Generalized interface signal handler, 4.3-compatible. 999 */ 1000 #ifndef _SYS_SYSPROTO_H_ 1001 struct osigvec_args { 1002 int signum; 1003 struct sigvec *nsv; 1004 struct sigvec *osv; 1005 }; 1006 #endif 1007 /* 1008 * MPSAFE 1009 */ 1010 /* ARGSUSED */ 1011 int 1012 osigvec(td, uap) 1013 struct thread *td; 1014 register struct osigvec_args *uap; 1015 { 1016 struct sigvec vec; 1017 struct sigaction nsa, osa; 1018 register struct sigaction *nsap, *osap; 1019 int error; 1020 1021 if (uap->signum <= 0 || uap->signum >= ONSIG) 1022 return (EINVAL); 1023 nsap = (uap->nsv != NULL) ? &nsa : NULL; 1024 osap = (uap->osv != NULL) ? &osa : NULL; 1025 if (nsap) { 1026 error = copyin(uap->nsv, &vec, sizeof(vec)); 1027 if (error) 1028 return (error); 1029 nsap->sa_handler = vec.sv_handler; 1030 OSIG2SIG(vec.sv_mask, nsap->sa_mask); 1031 nsap->sa_flags = vec.sv_flags; 1032 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */ 1033 #ifdef COMPAT_SUNOS 1034 nsap->sa_flags |= SA_USERTRAMP; 1035 #endif 1036 } 1037 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 1038 if (osap && !error) { 1039 vec.sv_handler = osap->sa_handler; 1040 SIG2OSIG(osap->sa_mask, vec.sv_mask); 1041 vec.sv_flags = osap->sa_flags; 1042 vec.sv_flags &= ~SA_NOCLDWAIT; 1043 vec.sv_flags ^= SA_RESTART; 1044 #ifdef COMPAT_SUNOS 1045 vec.sv_flags &= ~SA_NOCLDSTOP; 1046 #endif 1047 error = copyout(&vec, uap->osv, sizeof(vec)); 1048 } 1049 return (error); 1050 } 1051 1052 #ifndef _SYS_SYSPROTO_H_ 1053 struct osigblock_args { 1054 int mask; 1055 }; 1056 #endif 1057 /* 1058 * MPSAFE 1059 */ 1060 int 1061 osigblock(td, uap) 1062 register struct thread *td; 1063 struct osigblock_args *uap; 1064 { 1065 struct proc *p = td->td_proc; 1066 sigset_t set; 1067 1068 OSIG2SIG(uap->mask, set); 1069 SIG_CANTMASK(set); 1070 PROC_LOCK(p); 1071 SIG2OSIG(td->td_sigmask, td->td_retval[0]); 1072 SIGSETOR(td->td_sigmask, set); 1073 PROC_UNLOCK(p); 1074 return (0); 1075 } 1076 1077 #ifndef _SYS_SYSPROTO_H_ 1078 struct osigsetmask_args { 1079 int mask; 1080 }; 1081 #endif 1082 /* 1083 * MPSAFE 1084 */ 1085 int 1086 osigsetmask(td, uap) 1087 struct thread *td; 1088 struct osigsetmask_args *uap; 1089 { 1090 struct proc *p = td->td_proc; 1091 sigset_t set; 1092 1093 OSIG2SIG(uap->mask, set); 1094 SIG_CANTMASK(set); 1095 PROC_LOCK(p); 1096 SIG2OSIG(td->td_sigmask, td->td_retval[0]); 1097 SIGSETLO(td->td_sigmask, set); 1098 signotify(td); 1099 PROC_UNLOCK(p); 1100 return (0); 1101 } 1102 #endif /* COMPAT_43 || COMPAT_SUNOS */ 1103 1104 /* 1105 * Suspend process until signal, providing mask to be set 1106 * in the meantime. 1107 ***** XXXKSE this doesn't make sense under KSE. 1108 ***** Do we suspend the thread or all threads in the process? 1109 ***** How do we suspend threads running NOW on another processor? 1110 */ 1111 #ifndef _SYS_SYSPROTO_H_ 1112 struct sigsuspend_args { 1113 const sigset_t *sigmask; 1114 }; 1115 #endif 1116 /* 1117 * MPSAFE 1118 */ 1119 /* ARGSUSED */ 1120 int 1121 sigsuspend(td, uap) 1122 struct thread *td; 1123 struct sigsuspend_args *uap; 1124 { 1125 sigset_t mask; 1126 int error; 1127 1128 error = copyin(uap->sigmask, &mask, sizeof(mask)); 1129 if (error) 1130 return (error); 1131 return (kern_sigsuspend(td, mask)); 1132 } 1133 1134 int 1135 kern_sigsuspend(struct thread *td, sigset_t mask) 1136 { 1137 struct proc *p = td->td_proc; 1138 1139 /* 1140 * When returning from sigsuspend, we want 1141 * the old mask to be restored after the 1142 * signal handler has finished. Thus, we 1143 * save it here and mark the sigacts structure 1144 * to indicate this. 1145 */ 1146 PROC_LOCK(p); 1147 td->td_oldsigmask = td->td_sigmask; 1148 td->td_pflags |= TDP_OLDMASK; 1149 SIG_CANTMASK(mask); 1150 td->td_sigmask = mask; 1151 signotify(td); 1152 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0) 1153 /* void */; 1154 PROC_UNLOCK(p); 1155 /* always return EINTR rather than ERESTART... */ 1156 return (EINTR); 1157 } 1158 1159 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 1160 /* 1161 * Compatibility sigsuspend call for old binaries. Note nonstandard calling 1162 * convention: libc stub passes mask, not pointer, to save a copyin. 1163 */ 1164 #ifndef _SYS_SYSPROTO_H_ 1165 struct osigsuspend_args { 1166 osigset_t mask; 1167 }; 1168 #endif 1169 /* 1170 * MPSAFE 1171 */ 1172 /* ARGSUSED */ 1173 int 1174 osigsuspend(td, uap) 1175 struct thread *td; 1176 struct osigsuspend_args *uap; 1177 { 1178 struct proc *p = td->td_proc; 1179 sigset_t mask; 1180 1181 PROC_LOCK(p); 1182 td->td_oldsigmask = td->td_sigmask; 1183 td->td_pflags |= TDP_OLDMASK; 1184 OSIG2SIG(uap->mask, mask); 1185 SIG_CANTMASK(mask); 1186 SIGSETLO(td->td_sigmask, mask); 1187 signotify(td); 1188 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0) 1189 /* void */; 1190 PROC_UNLOCK(p); 1191 /* always return EINTR rather than ERESTART... */ 1192 return (EINTR); 1193 } 1194 #endif /* COMPAT_43 */ 1195 1196 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 1197 #ifndef _SYS_SYSPROTO_H_ 1198 struct osigstack_args { 1199 struct sigstack *nss; 1200 struct sigstack *oss; 1201 }; 1202 #endif 1203 /* 1204 * MPSAFE 1205 */ 1206 /* ARGSUSED */ 1207 int 1208 osigstack(td, uap) 1209 struct thread *td; 1210 register struct osigstack_args *uap; 1211 { 1212 struct sigstack nss, oss; 1213 int error = 0; 1214 1215 if (uap->nss != NULL) { 1216 error = copyin(uap->nss, &nss, sizeof(nss)); 1217 if (error) 1218 return (error); 1219 } 1220 oss.ss_sp = td->td_sigstk.ss_sp; 1221 oss.ss_onstack = sigonstack(cpu_getstack(td)); 1222 if (uap->nss != NULL) { 1223 td->td_sigstk.ss_sp = nss.ss_sp; 1224 td->td_sigstk.ss_size = 0; 1225 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK; 1226 td->td_pflags |= TDP_ALTSTACK; 1227 } 1228 if (uap->oss != NULL) 1229 error = copyout(&oss, uap->oss, sizeof(oss)); 1230 1231 return (error); 1232 } 1233 #endif /* COMPAT_43 || COMPAT_SUNOS */ 1234 1235 #ifndef _SYS_SYSPROTO_H_ 1236 struct sigaltstack_args { 1237 stack_t *ss; 1238 stack_t *oss; 1239 }; 1240 #endif 1241 /* 1242 * MPSAFE 1243 */ 1244 /* ARGSUSED */ 1245 int 1246 sigaltstack(td, uap) 1247 struct thread *td; 1248 register struct sigaltstack_args *uap; 1249 { 1250 stack_t ss, oss; 1251 int error; 1252 1253 if (uap->ss != NULL) { 1254 error = copyin(uap->ss, &ss, sizeof(ss)); 1255 if (error) 1256 return (error); 1257 } 1258 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL, 1259 (uap->oss != NULL) ? &oss : NULL); 1260 if (error) 1261 return (error); 1262 if (uap->oss != NULL) 1263 error = copyout(&oss, uap->oss, sizeof(stack_t)); 1264 return (error); 1265 } 1266 1267 int 1268 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss) 1269 { 1270 struct proc *p = td->td_proc; 1271 int oonstack; 1272 1273 oonstack = sigonstack(cpu_getstack(td)); 1274 1275 if (oss != NULL) { 1276 *oss = td->td_sigstk; 1277 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK) 1278 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; 1279 } 1280 1281 if (ss != NULL) { 1282 if (oonstack) 1283 return (EPERM); 1284 if ((ss->ss_flags & ~SS_DISABLE) != 0) 1285 return (EINVAL); 1286 if (!(ss->ss_flags & SS_DISABLE)) { 1287 if (ss->ss_size < p->p_sysent->sv_minsigstksz) { 1288 return (ENOMEM); 1289 } 1290 td->td_sigstk = *ss; 1291 td->td_pflags |= TDP_ALTSTACK; 1292 } else { 1293 td->td_pflags &= ~TDP_ALTSTACK; 1294 } 1295 } 1296 return (0); 1297 } 1298 1299 /* 1300 * Common code for kill process group/broadcast kill. 1301 * cp is calling process. 1302 */ 1303 static int 1304 killpg1(td, sig, pgid, all) 1305 register struct thread *td; 1306 int sig, pgid, all; 1307 { 1308 register struct proc *p; 1309 struct pgrp *pgrp; 1310 int nfound = 0; 1311 1312 if (all) { 1313 /* 1314 * broadcast 1315 */ 1316 sx_slock(&allproc_lock); 1317 LIST_FOREACH(p, &allproc, p_list) { 1318 PROC_LOCK(p); 1319 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || 1320 p == td->td_proc) { 1321 PROC_UNLOCK(p); 1322 continue; 1323 } 1324 if (p_cansignal(td, p, sig) == 0) { 1325 nfound++; 1326 if (sig) 1327 psignal(p, sig); 1328 } 1329 PROC_UNLOCK(p); 1330 } 1331 sx_sunlock(&allproc_lock); 1332 } else { 1333 sx_slock(&proctree_lock); 1334 if (pgid == 0) { 1335 /* 1336 * zero pgid means send to my process group. 1337 */ 1338 pgrp = td->td_proc->p_pgrp; 1339 PGRP_LOCK(pgrp); 1340 } else { 1341 pgrp = pgfind(pgid); 1342 if (pgrp == NULL) { 1343 sx_sunlock(&proctree_lock); 1344 return (ESRCH); 1345 } 1346 } 1347 sx_sunlock(&proctree_lock); 1348 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1349 PROC_LOCK(p); 1350 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM) { 1351 PROC_UNLOCK(p); 1352 continue; 1353 } 1354 if (p->p_state == PRS_ZOMBIE) { 1355 PROC_UNLOCK(p); 1356 continue; 1357 } 1358 if (p_cansignal(td, p, sig) == 0) { 1359 nfound++; 1360 if (sig) 1361 psignal(p, sig); 1362 } 1363 PROC_UNLOCK(p); 1364 } 1365 PGRP_UNLOCK(pgrp); 1366 } 1367 return (nfound ? 0 : ESRCH); 1368 } 1369 1370 #ifndef _SYS_SYSPROTO_H_ 1371 struct kill_args { 1372 int pid; 1373 int signum; 1374 }; 1375 #endif 1376 /* 1377 * MPSAFE 1378 */ 1379 /* ARGSUSED */ 1380 int 1381 kill(td, uap) 1382 register struct thread *td; 1383 register struct kill_args *uap; 1384 { 1385 register struct proc *p; 1386 int error; 1387 1388 if ((u_int)uap->signum > _SIG_MAXSIG) 1389 return (EINVAL); 1390 1391 if (uap->pid > 0) { 1392 /* kill single process */ 1393 if ((p = pfind(uap->pid)) == NULL) 1394 return (ESRCH); 1395 error = p_cansignal(td, p, uap->signum); 1396 if (error == 0 && uap->signum) 1397 psignal(p, uap->signum); 1398 PROC_UNLOCK(p); 1399 return (error); 1400 } 1401 switch (uap->pid) { 1402 case -1: /* broadcast signal */ 1403 return (killpg1(td, uap->signum, 0, 1)); 1404 case 0: /* signal own process group */ 1405 return (killpg1(td, uap->signum, 0, 0)); 1406 default: /* negative explicit process group */ 1407 return (killpg1(td, uap->signum, -uap->pid, 0)); 1408 } 1409 /* NOTREACHED */ 1410 } 1411 1412 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 1413 #ifndef _SYS_SYSPROTO_H_ 1414 struct okillpg_args { 1415 int pgid; 1416 int signum; 1417 }; 1418 #endif 1419 /* 1420 * MPSAFE 1421 */ 1422 /* ARGSUSED */ 1423 int 1424 okillpg(td, uap) 1425 struct thread *td; 1426 register struct okillpg_args *uap; 1427 { 1428 1429 if ((u_int)uap->signum > _SIG_MAXSIG) 1430 return (EINVAL); 1431 return (killpg1(td, uap->signum, uap->pgid, 0)); 1432 } 1433 #endif /* COMPAT_43 || COMPAT_SUNOS */ 1434 1435 /* 1436 * Send a signal to a process group. 1437 */ 1438 void 1439 gsignal(pgid, sig) 1440 int pgid, sig; 1441 { 1442 struct pgrp *pgrp; 1443 1444 if (pgid != 0) { 1445 sx_slock(&proctree_lock); 1446 pgrp = pgfind(pgid); 1447 sx_sunlock(&proctree_lock); 1448 if (pgrp != NULL) { 1449 pgsignal(pgrp, sig, 0); 1450 PGRP_UNLOCK(pgrp); 1451 } 1452 } 1453 } 1454 1455 /* 1456 * Send a signal to a process group. If checktty is 1, 1457 * limit to members which have a controlling terminal. 1458 */ 1459 void 1460 pgsignal(pgrp, sig, checkctty) 1461 struct pgrp *pgrp; 1462 int sig, checkctty; 1463 { 1464 register struct proc *p; 1465 1466 if (pgrp) { 1467 PGRP_LOCK_ASSERT(pgrp, MA_OWNED); 1468 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1469 PROC_LOCK(p); 1470 if (checkctty == 0 || p->p_flag & P_CONTROLT) 1471 psignal(p, sig); 1472 PROC_UNLOCK(p); 1473 } 1474 } 1475 } 1476 1477 /* 1478 * Send a signal caused by a trap to the current thread. 1479 * If it will be caught immediately, deliver it with correct code. 1480 * Otherwise, post it normally. 1481 * 1482 * MPSAFE 1483 */ 1484 void 1485 trapsignal(struct thread *td, int sig, u_long code) 1486 { 1487 struct sigacts *ps; 1488 struct proc *p; 1489 siginfo_t siginfo; 1490 int error; 1491 1492 p = td->td_proc; 1493 if (td->td_flags & TDF_SA) { 1494 if (td->td_mailbox == NULL) 1495 thread_user_enter(p, td); 1496 PROC_LOCK(p); 1497 if (td->td_mailbox) { 1498 SIGDELSET(td->td_sigmask, sig); 1499 mtx_lock_spin(&sched_lock); 1500 /* 1501 * Force scheduling an upcall, so UTS has chance to 1502 * process the signal before thread runs again in 1503 * userland. 1504 */ 1505 if (td->td_upcall) 1506 td->td_upcall->ku_flags |= KUF_DOUPCALL; 1507 mtx_unlock_spin(&sched_lock); 1508 } else { 1509 /* UTS caused a sync signal */ 1510 p->p_code = code; /* XXX for core dump/debugger */ 1511 p->p_sig = sig; /* XXX to verify code */ 1512 sigexit(td, sig); 1513 } 1514 } else { 1515 PROC_LOCK(p); 1516 } 1517 ps = p->p_sigacts; 1518 mtx_lock(&ps->ps_mtx); 1519 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) && 1520 !SIGISMEMBER(td->td_sigmask, sig)) { 1521 p->p_stats->p_ru.ru_nsignals++; 1522 #ifdef KTRACE 1523 if (KTRPOINT(curthread, KTR_PSIG)) 1524 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)], 1525 &td->td_sigmask, code); 1526 #endif 1527 if (!(td->td_flags & TDF_SA)) 1528 (*p->p_sysent->sv_sendsig)( 1529 ps->ps_sigact[_SIG_IDX(sig)], sig, 1530 &td->td_sigmask, code); 1531 else { 1532 cpu_thread_siginfo(sig, code, &siginfo); 1533 mtx_unlock(&ps->ps_mtx); 1534 PROC_UNLOCK(p); 1535 error = copyout(&siginfo, &td->td_mailbox->tm_syncsig, 1536 sizeof(siginfo)); 1537 PROC_LOCK(p); 1538 /* UTS memory corrupted */ 1539 if (error) 1540 sigexit(td, SIGILL); 1541 SIGADDSET(td->td_sigmask, sig); 1542 mtx_lock(&ps->ps_mtx); 1543 } 1544 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 1545 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 1546 SIGADDSET(td->td_sigmask, sig); 1547 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 1548 /* 1549 * See kern_sigaction() for origin of this code. 1550 */ 1551 SIGDELSET(ps->ps_sigcatch, sig); 1552 if (sig != SIGCONT && 1553 sigprop(sig) & SA_IGNORE) 1554 SIGADDSET(ps->ps_sigignore, sig); 1555 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 1556 } 1557 mtx_unlock(&ps->ps_mtx); 1558 } else { 1559 mtx_unlock(&ps->ps_mtx); 1560 p->p_code = code; /* XXX for core dump/debugger */ 1561 p->p_sig = sig; /* XXX to verify code */ 1562 tdsignal(td, sig, SIGTARGET_TD); 1563 } 1564 PROC_UNLOCK(p); 1565 } 1566 1567 static struct thread * 1568 sigtd(struct proc *p, int sig, int prop) 1569 { 1570 struct thread *td, *signal_td; 1571 1572 PROC_LOCK_ASSERT(p, MA_OWNED); 1573 1574 /* 1575 * First find a thread in sigwait state and signal belongs to 1576 * its wait set. POSIX's arguments is that speed of delivering signal 1577 * to sigwait thread is faster than delivering signal to user stack. 1578 * If we can not find sigwait thread, then find the first thread in 1579 * the proc that doesn't have this signal masked, an exception is 1580 * if current thread is sending signal to its process, and it does not 1581 * mask the signal, it should get the signal, this is another fast 1582 * way to deliver signal. 1583 */ 1584 signal_td = NULL; 1585 mtx_lock_spin(&sched_lock); 1586 FOREACH_THREAD_IN_PROC(p, td) { 1587 if (td->td_waitset != NULL && 1588 SIGISMEMBER(*(td->td_waitset), sig)) { 1589 mtx_unlock_spin(&sched_lock); 1590 return (td); 1591 } 1592 if (!SIGISMEMBER(td->td_sigmask, sig)) { 1593 if (td == curthread) 1594 signal_td = curthread; 1595 else if (signal_td == NULL) 1596 signal_td = td; 1597 } 1598 } 1599 if (signal_td == NULL) 1600 signal_td = FIRST_THREAD_IN_PROC(p); 1601 mtx_unlock_spin(&sched_lock); 1602 return (signal_td); 1603 } 1604 1605 /* 1606 * Send the signal to the process. If the signal has an action, the action 1607 * is usually performed by the target process rather than the caller; we add 1608 * the signal to the set of pending signals for the process. 1609 * 1610 * Exceptions: 1611 * o When a stop signal is sent to a sleeping process that takes the 1612 * default action, the process is stopped without awakening it. 1613 * o SIGCONT restarts stopped processes (or puts them back to sleep) 1614 * regardless of the signal action (eg, blocked or ignored). 1615 * 1616 * Other ignored signals are discarded immediately. 1617 * 1618 * MPSAFE 1619 */ 1620 void 1621 psignal(struct proc *p, int sig) 1622 { 1623 struct thread *td; 1624 int prop; 1625 1626 if (!_SIG_VALID(sig)) 1627 panic("psignal(): invalid signal"); 1628 1629 PROC_LOCK_ASSERT(p, MA_OWNED); 1630 prop = sigprop(sig); 1631 1632 /* 1633 * Find a thread to deliver the signal to. 1634 */ 1635 td = sigtd(p, sig, prop); 1636 1637 tdsignal(td, sig, SIGTARGET_P); 1638 } 1639 1640 /* 1641 * MPSAFE 1642 */ 1643 void 1644 tdsignal(struct thread *td, int sig, sigtarget_t target) 1645 { 1646 sigset_t saved; 1647 struct proc *p = td->td_proc; 1648 1649 if (p->p_flag & P_SA) 1650 saved = p->p_siglist; 1651 do_tdsignal(td, sig, target); 1652 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) { 1653 if (SIGSETEQ(saved, p->p_siglist)) 1654 return; 1655 else { 1656 /* pending set changed */ 1657 p->p_flag |= P_SIGEVENT; 1658 wakeup(&p->p_siglist); 1659 } 1660 } 1661 } 1662 1663 static void 1664 do_tdsignal(struct thread *td, int sig, sigtarget_t target) 1665 { 1666 struct proc *p; 1667 register sig_t action; 1668 sigset_t *siglist; 1669 struct thread *td0; 1670 register int prop; 1671 struct sigacts *ps; 1672 1673 if (!_SIG_VALID(sig)) 1674 panic("do_tdsignal(): invalid signal"); 1675 1676 p = td->td_proc; 1677 ps = p->p_sigacts; 1678 1679 PROC_LOCK_ASSERT(p, MA_OWNED); 1680 KNOTE(&p->p_klist, NOTE_SIGNAL | sig); 1681 1682 prop = sigprop(sig); 1683 1684 /* 1685 * If the signal is blocked and not destined for this thread, then 1686 * assign it to the process so that we can find it later in the first 1687 * thread that unblocks it. Otherwise, assign it to this thread now. 1688 */ 1689 if (target == SIGTARGET_TD) { 1690 siglist = &td->td_siglist; 1691 } else { 1692 if (!SIGISMEMBER(td->td_sigmask, sig)) 1693 siglist = &td->td_siglist; 1694 else if (td->td_waitset != NULL && 1695 SIGISMEMBER(*(td->td_waitset), sig)) 1696 siglist = &td->td_siglist; 1697 else 1698 siglist = &p->p_siglist; 1699 } 1700 1701 /* 1702 * If proc is traced, always give parent a chance; 1703 * if signal event is tracked by procfs, give *that* 1704 * a chance, as well. 1705 */ 1706 if ((p->p_flag & P_TRACED) || (p->p_stops & S_SIG)) { 1707 action = SIG_DFL; 1708 } else { 1709 /* 1710 * If the signal is being ignored, 1711 * then we forget about it immediately. 1712 * (Note: we don't set SIGCONT in ps_sigignore, 1713 * and if it is set to SIG_IGN, 1714 * action will be SIG_DFL here.) 1715 */ 1716 mtx_lock(&ps->ps_mtx); 1717 if (SIGISMEMBER(ps->ps_sigignore, sig) || 1718 (p->p_flag & P_WEXIT)) { 1719 mtx_unlock(&ps->ps_mtx); 1720 return; 1721 } 1722 if (((td->td_waitset == NULL) && 1723 SIGISMEMBER(td->td_sigmask, sig)) || 1724 ((td->td_waitset != NULL) && 1725 SIGISMEMBER(td->td_sigmask, sig) && 1726 !SIGISMEMBER(*(td->td_waitset), sig))) 1727 action = SIG_HOLD; 1728 else if (SIGISMEMBER(ps->ps_sigcatch, sig)) 1729 action = SIG_CATCH; 1730 else 1731 action = SIG_DFL; 1732 mtx_unlock(&ps->ps_mtx); 1733 } 1734 1735 if (prop & SA_CONT) { 1736 SIG_STOPSIGMASK(p->p_siglist); 1737 /* 1738 * XXX Should investigate leaving STOP and CONT sigs only in 1739 * the proc's siglist. 1740 */ 1741 mtx_lock_spin(&sched_lock); 1742 FOREACH_THREAD_IN_PROC(p, td0) 1743 SIG_STOPSIGMASK(td0->td_siglist); 1744 mtx_unlock_spin(&sched_lock); 1745 } 1746 1747 if (prop & SA_STOP) { 1748 /* 1749 * If sending a tty stop signal to a member of an orphaned 1750 * process group, discard the signal here if the action 1751 * is default; don't stop the process below if sleeping, 1752 * and don't clear any pending SIGCONT. 1753 */ 1754 if ((prop & SA_TTYSTOP) && 1755 (p->p_pgrp->pg_jobc == 0) && 1756 (action == SIG_DFL)) 1757 return; 1758 SIG_CONTSIGMASK(p->p_siglist); 1759 mtx_lock_spin(&sched_lock); 1760 FOREACH_THREAD_IN_PROC(p, td0) 1761 SIG_CONTSIGMASK(td0->td_siglist); 1762 mtx_unlock_spin(&sched_lock); 1763 p->p_flag &= ~P_CONTINUED; 1764 } 1765 1766 SIGADDSET(*siglist, sig); 1767 signotify(td); /* uses schedlock */ 1768 if (siglist == &td->td_siglist && (td->td_waitset != NULL) && 1769 action != SIG_HOLD) { 1770 td->td_waitset = NULL; 1771 } 1772 1773 /* 1774 * Defer further processing for signals which are held, 1775 * except that stopped processes must be continued by SIGCONT. 1776 */ 1777 if (action == SIG_HOLD && 1778 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG))) 1779 return; 1780 /* 1781 * Some signals have a process-wide effect and a per-thread 1782 * component. Most processing occurs when the process next 1783 * tries to cross the user boundary, however there are some 1784 * times when processing needs to be done immediatly, such as 1785 * waking up threads so that they can cross the user boundary. 1786 * We try do the per-process part here. 1787 */ 1788 if (P_SHOULDSTOP(p)) { 1789 /* 1790 * The process is in stopped mode. All the threads should be 1791 * either winding down or already on the suspended queue. 1792 */ 1793 if (p->p_flag & P_TRACED) { 1794 /* 1795 * The traced process is already stopped, 1796 * so no further action is necessary. 1797 * No signal can restart us. 1798 */ 1799 goto out; 1800 } 1801 1802 if (sig == SIGKILL) { 1803 /* 1804 * SIGKILL sets process running. 1805 * It will die elsewhere. 1806 * All threads must be restarted. 1807 */ 1808 p->p_flag &= ~P_STOPPED; 1809 goto runfast; 1810 } 1811 1812 if (prop & SA_CONT) { 1813 /* 1814 * If SIGCONT is default (or ignored), we continue the 1815 * process but don't leave the signal in siglist as 1816 * it has no further action. If SIGCONT is held, we 1817 * continue the process and leave the signal in 1818 * siglist. If the process catches SIGCONT, let it 1819 * handle the signal itself. If it isn't waiting on 1820 * an event, it goes back to run state. 1821 * Otherwise, process goes back to sleep state. 1822 */ 1823 p->p_flag &= ~P_STOPPED_SIG; 1824 p->p_flag |= P_CONTINUED; 1825 if (action == SIG_DFL) { 1826 SIGDELSET(*siglist, sig); 1827 } else if (action == SIG_CATCH) { 1828 /* 1829 * The process wants to catch it so it needs 1830 * to run at least one thread, but which one? 1831 * It would seem that the answer would be to 1832 * run an upcall in the next KSE to run, and 1833 * deliver the signal that way. In a NON KSE 1834 * process, we need to make sure that the 1835 * single thread is runnable asap. 1836 * XXXKSE for now however, make them all run. 1837 */ 1838 goto runfast; 1839 } 1840 /* 1841 * The signal is not ignored or caught. 1842 */ 1843 mtx_lock_spin(&sched_lock); 1844 thread_unsuspend(p); 1845 mtx_unlock_spin(&sched_lock); 1846 goto out; 1847 } 1848 1849 if (prop & SA_STOP) { 1850 /* 1851 * Already stopped, don't need to stop again 1852 * (If we did the shell could get confused). 1853 * Just make sure the signal STOP bit set. 1854 */ 1855 p->p_flag |= P_STOPPED_SIG; 1856 SIGDELSET(*siglist, sig); 1857 goto out; 1858 } 1859 1860 /* 1861 * All other kinds of signals: 1862 * If a thread is sleeping interruptibly, simulate a 1863 * wakeup so that when it is continued it will be made 1864 * runnable and can look at the signal. However, don't make 1865 * the PROCESS runnable, leave it stopped. 1866 * It may run a bit until it hits a thread_suspend_check(). 1867 */ 1868 mtx_lock_spin(&sched_lock); 1869 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR)) 1870 sleepq_abort(td); 1871 mtx_unlock_spin(&sched_lock); 1872 goto out; 1873 /* 1874 * Mutexes are short lived. Threads waiting on them will 1875 * hit thread_suspend_check() soon. 1876 */ 1877 } else if (p->p_state == PRS_NORMAL) { 1878 if ((p->p_flag & P_TRACED) || (action != SIG_DFL) || 1879 !(prop & SA_STOP)) { 1880 mtx_lock_spin(&sched_lock); 1881 tdsigwakeup(td, sig, action); 1882 mtx_unlock_spin(&sched_lock); 1883 goto out; 1884 } 1885 if (prop & SA_STOP) { 1886 if (p->p_flag & P_PPWAIT) 1887 goto out; 1888 p->p_flag |= P_STOPPED_SIG; 1889 p->p_xstat = sig; 1890 mtx_lock_spin(&sched_lock); 1891 FOREACH_THREAD_IN_PROC(p, td0) { 1892 if (TD_IS_SLEEPING(td0) && 1893 (td0->td_flags & TDF_SINTR) && 1894 !TD_IS_SUSPENDED(td0)) { 1895 thread_suspend_one(td0); 1896 } else if (td != td0) { 1897 td0->td_flags |= TDF_ASTPENDING; 1898 } 1899 } 1900 thread_stopped(p); 1901 if (p->p_numthreads == p->p_suspcount) { 1902 SIGDELSET(p->p_siglist, p->p_xstat); 1903 FOREACH_THREAD_IN_PROC(p, td0) 1904 SIGDELSET(td0->td_siglist, p->p_xstat); 1905 } 1906 mtx_unlock_spin(&sched_lock); 1907 goto out; 1908 } 1909 else 1910 goto runfast; 1911 /* NOTREACHED */ 1912 } else { 1913 /* Not in "NORMAL" state. discard the signal. */ 1914 SIGDELSET(*siglist, sig); 1915 goto out; 1916 } 1917 1918 /* 1919 * The process is not stopped so we need to apply the signal to all the 1920 * running threads. 1921 */ 1922 1923 runfast: 1924 mtx_lock_spin(&sched_lock); 1925 tdsigwakeup(td, sig, action); 1926 thread_unsuspend(p); 1927 mtx_unlock_spin(&sched_lock); 1928 out: 1929 /* If we jump here, sched_lock should not be owned. */ 1930 mtx_assert(&sched_lock, MA_NOTOWNED); 1931 } 1932 1933 /* 1934 * The force of a signal has been directed against a single 1935 * thread. We need to see what we can do about knocking it 1936 * out of any sleep it may be in etc. 1937 */ 1938 static void 1939 tdsigwakeup(struct thread *td, int sig, sig_t action) 1940 { 1941 struct proc *p = td->td_proc; 1942 register int prop; 1943 1944 PROC_LOCK_ASSERT(p, MA_OWNED); 1945 mtx_assert(&sched_lock, MA_OWNED); 1946 prop = sigprop(sig); 1947 /* 1948 * Bring the priority of a thread up if we want it to get 1949 * killed in this lifetime. 1950 */ 1951 if ((action == SIG_DFL) && (prop & SA_KILL)) { 1952 if (td->td_priority > PUSER) { 1953 td->td_priority = PUSER; 1954 } 1955 } 1956 if (TD_IS_SLEEPING(td)) { 1957 /* 1958 * If thread is sleeping uninterruptibly 1959 * we can't interrupt the sleep... the signal will 1960 * be noticed when the process returns through 1961 * trap() or syscall(). 1962 */ 1963 if ((td->td_flags & TDF_SINTR) == 0) 1964 return; 1965 /* 1966 * Process is sleeping and traced. Make it runnable 1967 * so it can discover the signal in issignal() and stop 1968 * for its parent. 1969 */ 1970 if (p->p_flag & P_TRACED) { 1971 p->p_flag &= ~P_STOPPED_TRACE; 1972 } else { 1973 1974 /* 1975 * If SIGCONT is default (or ignored) and process is 1976 * asleep, we are finished; the process should not 1977 * be awakened. 1978 */ 1979 if ((prop & SA_CONT) && action == SIG_DFL) { 1980 SIGDELSET(p->p_siglist, sig); 1981 /* 1982 * It may be on either list in this state. 1983 * Remove from both for now. 1984 */ 1985 SIGDELSET(td->td_siglist, sig); 1986 return; 1987 } 1988 1989 /* 1990 * Raise priority to at least PUSER. 1991 */ 1992 if (td->td_priority > PUSER) 1993 td->td_priority = PUSER; 1994 } 1995 sleepq_abort(td); 1996 } 1997 #ifdef SMP 1998 else { 1999 /* 2000 * Other states do nothing with the signal immediatly, 2001 * other than kicking ourselves if we are running. 2002 * It will either never be noticed, or noticed very soon. 2003 */ 2004 if (TD_IS_RUNNING(td) && td != curthread) 2005 forward_signal(td); 2006 } 2007 #endif 2008 } 2009 2010 void 2011 ptracestop(struct thread *td, int sig) 2012 { 2013 struct proc *p = td->td_proc; 2014 2015 PROC_LOCK_ASSERT(p, MA_OWNED); 2016 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2017 &p->p_mtx.mtx_object, "Stopping for traced signal"); 2018 2019 p->p_xstat = sig; 2020 PROC_LOCK(p->p_pptr); 2021 psignal(p->p_pptr, SIGCHLD); 2022 PROC_UNLOCK(p->p_pptr); 2023 stop(p); 2024 mtx_lock_spin(&sched_lock); 2025 thread_suspend_one(td); 2026 PROC_UNLOCK(p); 2027 DROP_GIANT(); 2028 mi_switch(SW_INVOL); 2029 mtx_unlock_spin(&sched_lock); 2030 PICKUP_GIANT(); 2031 } 2032 2033 /* 2034 * If the current process has received a signal (should be caught or cause 2035 * termination, should interrupt current syscall), return the signal number. 2036 * Stop signals with default action are processed immediately, then cleared; 2037 * they aren't returned. This is checked after each entry to the system for 2038 * a syscall or trap (though this can usually be done without calling issignal 2039 * by checking the pending signal masks in cursig.) The normal call 2040 * sequence is 2041 * 2042 * while (sig = cursig(curthread)) 2043 * postsig(sig); 2044 */ 2045 static int 2046 issignal(td) 2047 struct thread *td; 2048 { 2049 struct proc *p; 2050 struct sigacts *ps; 2051 sigset_t sigpending; 2052 int sig, prop; 2053 struct thread *td0; 2054 2055 p = td->td_proc; 2056 ps = p->p_sigacts; 2057 mtx_assert(&ps->ps_mtx, MA_OWNED); 2058 PROC_LOCK_ASSERT(p, MA_OWNED); 2059 for (;;) { 2060 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG); 2061 2062 sigpending = td->td_siglist; 2063 SIGSETNAND(sigpending, td->td_sigmask); 2064 2065 if (p->p_flag & P_PPWAIT) 2066 SIG_STOPSIGMASK(sigpending); 2067 if (SIGISEMPTY(sigpending)) /* no signal to send */ 2068 return (0); 2069 sig = sig_ffs(&sigpending); 2070 2071 if (p->p_stops & S_SIG) { 2072 mtx_unlock(&ps->ps_mtx); 2073 stopevent(p, S_SIG, sig); 2074 mtx_lock(&ps->ps_mtx); 2075 } 2076 2077 /* 2078 * We should see pending but ignored signals 2079 * only if P_TRACED was on when they were posted. 2080 */ 2081 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) { 2082 SIGDELSET(td->td_siglist, sig); 2083 continue; 2084 } 2085 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) { 2086 /* 2087 * If traced, always stop. 2088 */ 2089 mtx_unlock(&ps->ps_mtx); 2090 ptracestop(td, sig); 2091 PROC_LOCK(p); 2092 mtx_lock(&ps->ps_mtx); 2093 2094 /* 2095 * If parent wants us to take the signal, 2096 * then it will leave it in p->p_xstat; 2097 * otherwise we just look for signals again. 2098 */ 2099 SIGDELSET(td->td_siglist, sig); /* clear old signal */ 2100 sig = p->p_xstat; 2101 if (sig == 0) 2102 continue; 2103 2104 /* 2105 * If the traced bit got turned off, go back up 2106 * to the top to rescan signals. This ensures 2107 * that p_sig* and p_sigact are consistent. 2108 */ 2109 if ((p->p_flag & P_TRACED) == 0) 2110 continue; 2111 2112 /* 2113 * Put the new signal into td_siglist. If the 2114 * signal is being masked, look for other signals. 2115 */ 2116 SIGADDSET(td->td_siglist, sig); 2117 if (SIGISMEMBER(td->td_sigmask, sig)) 2118 continue; 2119 signotify(td); 2120 } 2121 2122 prop = sigprop(sig); 2123 2124 /* 2125 * Decide whether the signal should be returned. 2126 * Return the signal's number, or fall through 2127 * to clear it from the pending mask. 2128 */ 2129 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) { 2130 2131 case (intptr_t)SIG_DFL: 2132 /* 2133 * Don't take default actions on system processes. 2134 */ 2135 if (p->p_pid <= 1) { 2136 #ifdef DIAGNOSTIC 2137 /* 2138 * Are you sure you want to ignore SIGSEGV 2139 * in init? XXX 2140 */ 2141 printf("Process (pid %lu) got signal %d\n", 2142 (u_long)p->p_pid, sig); 2143 #endif 2144 break; /* == ignore */ 2145 } 2146 /* 2147 * If there is a pending stop signal to process 2148 * with default action, stop here, 2149 * then clear the signal. However, 2150 * if process is member of an orphaned 2151 * process group, ignore tty stop signals. 2152 */ 2153 if (prop & SA_STOP) { 2154 if (p->p_flag & P_TRACED || 2155 (p->p_pgrp->pg_jobc == 0 && 2156 prop & SA_TTYSTOP)) 2157 break; /* == ignore */ 2158 mtx_unlock(&ps->ps_mtx); 2159 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2160 &p->p_mtx.mtx_object, "Catching SIGSTOP"); 2161 p->p_flag |= P_STOPPED_SIG; 2162 p->p_xstat = sig; 2163 mtx_lock_spin(&sched_lock); 2164 FOREACH_THREAD_IN_PROC(p, td0) { 2165 if (TD_IS_SLEEPING(td0) && 2166 (td0->td_flags & TDF_SINTR) && 2167 !TD_IS_SUSPENDED(td0)) { 2168 thread_suspend_one(td0); 2169 } else if (td != td0) { 2170 td0->td_flags |= TDF_ASTPENDING; 2171 } 2172 } 2173 thread_stopped(p); 2174 thread_suspend_one(td); 2175 PROC_UNLOCK(p); 2176 DROP_GIANT(); 2177 mi_switch(SW_INVOL); 2178 mtx_unlock_spin(&sched_lock); 2179 PICKUP_GIANT(); 2180 PROC_LOCK(p); 2181 mtx_lock(&ps->ps_mtx); 2182 break; 2183 } else if (prop & SA_IGNORE) { 2184 /* 2185 * Except for SIGCONT, shouldn't get here. 2186 * Default action is to ignore; drop it. 2187 */ 2188 break; /* == ignore */ 2189 } else 2190 return (sig); 2191 /*NOTREACHED*/ 2192 2193 case (intptr_t)SIG_IGN: 2194 /* 2195 * Masking above should prevent us ever trying 2196 * to take action on an ignored signal other 2197 * than SIGCONT, unless process is traced. 2198 */ 2199 if ((prop & SA_CONT) == 0 && 2200 (p->p_flag & P_TRACED) == 0) 2201 printf("issignal\n"); 2202 break; /* == ignore */ 2203 2204 default: 2205 /* 2206 * This signal has an action, let 2207 * postsig() process it. 2208 */ 2209 return (sig); 2210 } 2211 SIGDELSET(td->td_siglist, sig); /* take the signal! */ 2212 } 2213 /* NOTREACHED */ 2214 } 2215 2216 /* 2217 * Put the argument process into the stopped state and notify the parent 2218 * via wakeup. Signals are handled elsewhere. The process must not be 2219 * on the run queue. Must be called with the proc p locked. 2220 */ 2221 static void 2222 stop(struct proc *p) 2223 { 2224 2225 PROC_LOCK_ASSERT(p, MA_OWNED); 2226 p->p_flag |= P_STOPPED_SIG; 2227 p->p_flag &= ~P_WAITED; 2228 wakeup(p->p_pptr); 2229 } 2230 2231 /* 2232 * MPSAFE 2233 */ 2234 void 2235 thread_stopped(struct proc *p) 2236 { 2237 struct proc *p1 = curthread->td_proc; 2238 struct sigacts *ps; 2239 int n; 2240 2241 PROC_LOCK_ASSERT(p, MA_OWNED); 2242 mtx_assert(&sched_lock, MA_OWNED); 2243 n = p->p_suspcount; 2244 if (p == p1) 2245 n++; 2246 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) { 2247 mtx_unlock_spin(&sched_lock); 2248 stop(p); 2249 PROC_LOCK(p->p_pptr); 2250 ps = p->p_pptr->p_sigacts; 2251 mtx_lock(&ps->ps_mtx); 2252 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) { 2253 mtx_unlock(&ps->ps_mtx); 2254 psignal(p->p_pptr, SIGCHLD); 2255 } else 2256 mtx_unlock(&ps->ps_mtx); 2257 PROC_UNLOCK(p->p_pptr); 2258 mtx_lock_spin(&sched_lock); 2259 } 2260 } 2261 2262 /* 2263 * Take the action for the specified signal 2264 * from the current set of pending signals. 2265 */ 2266 void 2267 postsig(sig) 2268 register int sig; 2269 { 2270 struct thread *td = curthread; 2271 register struct proc *p = td->td_proc; 2272 struct sigacts *ps; 2273 sig_t action; 2274 sigset_t returnmask; 2275 int code; 2276 2277 KASSERT(sig != 0, ("postsig")); 2278 2279 PROC_LOCK_ASSERT(p, MA_OWNED); 2280 ps = p->p_sigacts; 2281 mtx_assert(&ps->ps_mtx, MA_OWNED); 2282 SIGDELSET(td->td_siglist, sig); 2283 action = ps->ps_sigact[_SIG_IDX(sig)]; 2284 #ifdef KTRACE 2285 if (KTRPOINT(td, KTR_PSIG)) 2286 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ? 2287 &td->td_oldsigmask : &td->td_sigmask, 0); 2288 #endif 2289 if (p->p_stops & S_SIG) { 2290 mtx_unlock(&ps->ps_mtx); 2291 stopevent(p, S_SIG, sig); 2292 mtx_lock(&ps->ps_mtx); 2293 } 2294 2295 if (!(td->td_flags & TDF_SA && td->td_mailbox) && 2296 action == SIG_DFL) { 2297 /* 2298 * Default action, where the default is to kill 2299 * the process. (Other cases were ignored above.) 2300 */ 2301 mtx_unlock(&ps->ps_mtx); 2302 sigexit(td, sig); 2303 /* NOTREACHED */ 2304 } else { 2305 if (td->td_flags & TDF_SA && td->td_mailbox) { 2306 if (sig == SIGKILL) { 2307 mtx_unlock(&ps->ps_mtx); 2308 sigexit(td, sig); 2309 } 2310 } 2311 2312 /* 2313 * If we get here, the signal must be caught. 2314 */ 2315 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig), 2316 ("postsig action")); 2317 /* 2318 * Set the new mask value and also defer further 2319 * occurrences of this signal. 2320 * 2321 * Special case: user has done a sigsuspend. Here the 2322 * current mask is not of interest, but rather the 2323 * mask from before the sigsuspend is what we want 2324 * restored after the signal processing is completed. 2325 */ 2326 if (td->td_pflags & TDP_OLDMASK) { 2327 returnmask = td->td_oldsigmask; 2328 td->td_pflags &= ~TDP_OLDMASK; 2329 } else 2330 returnmask = td->td_sigmask; 2331 2332 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 2333 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 2334 SIGADDSET(td->td_sigmask, sig); 2335 2336 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 2337 /* 2338 * See kern_sigaction() for origin of this code. 2339 */ 2340 SIGDELSET(ps->ps_sigcatch, sig); 2341 if (sig != SIGCONT && 2342 sigprop(sig) & SA_IGNORE) 2343 SIGADDSET(ps->ps_sigignore, sig); 2344 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 2345 } 2346 p->p_stats->p_ru.ru_nsignals++; 2347 if (p->p_sig != sig) { 2348 code = 0; 2349 } else { 2350 code = p->p_code; 2351 p->p_code = 0; 2352 p->p_sig = 0; 2353 } 2354 if (td->td_flags & TDF_SA && td->td_mailbox) 2355 thread_signal_add(curthread, sig); 2356 else 2357 (*p->p_sysent->sv_sendsig)(action, sig, 2358 &returnmask, code); 2359 } 2360 } 2361 2362 /* 2363 * Kill the current process for stated reason. 2364 */ 2365 void 2366 killproc(p, why) 2367 struct proc *p; 2368 char *why; 2369 { 2370 2371 PROC_LOCK_ASSERT(p, MA_OWNED); 2372 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", 2373 p, p->p_pid, p->p_comm); 2374 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm, 2375 p->p_ucred ? p->p_ucred->cr_uid : -1, why); 2376 psignal(p, SIGKILL); 2377 } 2378 2379 /* 2380 * Force the current process to exit with the specified signal, dumping core 2381 * if appropriate. We bypass the normal tests for masked and caught signals, 2382 * allowing unrecoverable failures to terminate the process without changing 2383 * signal state. Mark the accounting record with the signal termination. 2384 * If dumping core, save the signal number for the debugger. Calls exit and 2385 * does not return. 2386 * 2387 * MPSAFE 2388 */ 2389 void 2390 sigexit(td, sig) 2391 struct thread *td; 2392 int sig; 2393 { 2394 struct proc *p = td->td_proc; 2395 2396 PROC_LOCK_ASSERT(p, MA_OWNED); 2397 p->p_acflag |= AXSIG; 2398 if (sigprop(sig) & SA_CORE) { 2399 p->p_sig = sig; 2400 /* 2401 * Log signals which would cause core dumps 2402 * (Log as LOG_INFO to appease those who don't want 2403 * these messages.) 2404 * XXX : Todo, as well as euid, write out ruid too 2405 * Note that coredump() drops proc lock. 2406 */ 2407 if (coredump(td) == 0) 2408 sig |= WCOREFLAG; 2409 if (kern_logsigexit) 2410 log(LOG_INFO, 2411 "pid %d (%s), uid %d: exited on signal %d%s\n", 2412 p->p_pid, p->p_comm, 2413 td->td_ucred ? td->td_ucred->cr_uid : -1, 2414 sig &~ WCOREFLAG, 2415 sig & WCOREFLAG ? " (core dumped)" : ""); 2416 } else 2417 PROC_UNLOCK(p); 2418 exit1(td, W_EXITCODE(0, sig)); 2419 /* NOTREACHED */ 2420 } 2421 2422 static char corefilename[MAXPATHLEN+1] = {"%N.core"}; 2423 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename, 2424 sizeof(corefilename), "process corefile name format string"); 2425 2426 /* 2427 * expand_name(name, uid, pid) 2428 * Expand the name described in corefilename, using name, uid, and pid. 2429 * corefilename is a printf-like string, with three format specifiers: 2430 * %N name of process ("name") 2431 * %P process id (pid) 2432 * %U user id (uid) 2433 * For example, "%N.core" is the default; they can be disabled completely 2434 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P". 2435 * This is controlled by the sysctl variable kern.corefile (see above). 2436 */ 2437 2438 static char * 2439 expand_name(name, uid, pid) 2440 const char *name; 2441 uid_t uid; 2442 pid_t pid; 2443 { 2444 const char *format, *appendstr; 2445 char *temp; 2446 char buf[11]; /* Buffer for pid/uid -- max 4B */ 2447 size_t i, l, n; 2448 2449 format = corefilename; 2450 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO); 2451 if (temp == NULL) 2452 return (NULL); 2453 for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) { 2454 switch (format[i]) { 2455 case '%': /* Format character */ 2456 i++; 2457 switch (format[i]) { 2458 case '%': 2459 appendstr = "%"; 2460 break; 2461 case 'N': /* process name */ 2462 appendstr = name; 2463 break; 2464 case 'P': /* process id */ 2465 sprintf(buf, "%u", pid); 2466 appendstr = buf; 2467 break; 2468 case 'U': /* user id */ 2469 sprintf(buf, "%u", uid); 2470 appendstr = buf; 2471 break; 2472 default: 2473 appendstr = ""; 2474 log(LOG_ERR, 2475 "Unknown format character %c in `%s'\n", 2476 format[i], format); 2477 } 2478 l = strlen(appendstr); 2479 if ((n + l) >= MAXPATHLEN) 2480 goto toolong; 2481 memcpy(temp + n, appendstr, l); 2482 n += l; 2483 break; 2484 default: 2485 temp[n++] = format[i]; 2486 } 2487 } 2488 if (format[i] != '\0') 2489 goto toolong; 2490 return (temp); 2491 toolong: 2492 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too long\n", 2493 (long)pid, name, (u_long)uid); 2494 free(temp, M_TEMP); 2495 return (NULL); 2496 } 2497 2498 /* 2499 * Dump a process' core. The main routine does some 2500 * policy checking, and creates the name of the coredump; 2501 * then it passes on a vnode and a size limit to the process-specific 2502 * coredump routine if there is one; if there _is not_ one, it returns 2503 * ENOSYS; otherwise it returns the error from the process-specific routine. 2504 */ 2505 2506 static int 2507 coredump(struct thread *td) 2508 { 2509 struct proc *p = td->td_proc; 2510 register struct vnode *vp; 2511 register struct ucred *cred = td->td_ucred; 2512 struct flock lf; 2513 struct nameidata nd; 2514 struct vattr vattr; 2515 int error, error1, flags, locked; 2516 struct mount *mp; 2517 char *name; /* name of corefile */ 2518 off_t limit; 2519 2520 PROC_LOCK_ASSERT(p, MA_OWNED); 2521 _STOPEVENT(p, S_CORE, 0); 2522 2523 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) { 2524 PROC_UNLOCK(p); 2525 return (EFAULT); 2526 } 2527 2528 /* 2529 * Note that the bulk of limit checking is done after 2530 * the corefile is created. The exception is if the limit 2531 * for corefiles is 0, in which case we don't bother 2532 * creating the corefile at all. This layout means that 2533 * a corefile is truncated instead of not being created, 2534 * if it is larger than the limit. 2535 */ 2536 limit = (off_t)lim_cur(p, RLIMIT_CORE); 2537 PROC_UNLOCK(p); 2538 if (limit == 0) 2539 return (EFBIG); 2540 2541 mtx_lock(&Giant); 2542 restart: 2543 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid); 2544 if (name == NULL) { 2545 mtx_unlock(&Giant); 2546 return (EINVAL); 2547 } 2548 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); /* XXXKSE */ 2549 flags = O_CREAT | FWRITE | O_NOFOLLOW; 2550 error = vn_open(&nd, &flags, S_IRUSR | S_IWUSR, -1); 2551 free(name, M_TEMP); 2552 if (error) { 2553 mtx_unlock(&Giant); 2554 return (error); 2555 } 2556 NDFREE(&nd, NDF_ONLY_PNBUF); 2557 vp = nd.ni_vp; 2558 2559 /* Don't dump to non-regular files or files with links. */ 2560 if (vp->v_type != VREG || 2561 VOP_GETATTR(vp, &vattr, cred, td) || vattr.va_nlink != 1) { 2562 VOP_UNLOCK(vp, 0, td); 2563 error = EFAULT; 2564 goto out; 2565 } 2566 2567 VOP_UNLOCK(vp, 0, td); 2568 lf.l_whence = SEEK_SET; 2569 lf.l_start = 0; 2570 lf.l_len = 0; 2571 lf.l_type = F_WRLCK; 2572 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0); 2573 2574 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 2575 lf.l_type = F_UNLCK; 2576 if (locked) 2577 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2578 if ((error = vn_close(vp, FWRITE, cred, td)) != 0) 2579 return (error); 2580 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0) 2581 return (error); 2582 goto restart; 2583 } 2584 2585 VATTR_NULL(&vattr); 2586 vattr.va_size = 0; 2587 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 2588 VOP_LEASE(vp, td, cred, LEASE_WRITE); 2589 VOP_SETATTR(vp, &vattr, cred, td); 2590 VOP_UNLOCK(vp, 0, td); 2591 PROC_LOCK(p); 2592 p->p_acflag |= ACORE; 2593 PROC_UNLOCK(p); 2594 2595 error = p->p_sysent->sv_coredump ? 2596 p->p_sysent->sv_coredump(td, vp, limit) : 2597 ENOSYS; 2598 2599 if (locked) { 2600 lf.l_type = F_UNLCK; 2601 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2602 } 2603 vn_finished_write(mp); 2604 out: 2605 error1 = vn_close(vp, FWRITE, cred, td); 2606 mtx_unlock(&Giant); 2607 if (error == 0) 2608 error = error1; 2609 return (error); 2610 } 2611 2612 /* 2613 * Nonexistent system call-- signal process (may want to handle it). 2614 * Flag error in case process won't see signal immediately (blocked or ignored). 2615 */ 2616 #ifndef _SYS_SYSPROTO_H_ 2617 struct nosys_args { 2618 int dummy; 2619 }; 2620 #endif 2621 /* 2622 * MPSAFE 2623 */ 2624 /* ARGSUSED */ 2625 int 2626 nosys(td, args) 2627 struct thread *td; 2628 struct nosys_args *args; 2629 { 2630 struct proc *p = td->td_proc; 2631 2632 PROC_LOCK(p); 2633 psignal(p, SIGSYS); 2634 PROC_UNLOCK(p); 2635 return (ENOSYS); 2636 } 2637 2638 /* 2639 * Send a SIGIO or SIGURG signal to a process or process group using 2640 * stored credentials rather than those of the current process. 2641 */ 2642 void 2643 pgsigio(sigiop, sig, checkctty) 2644 struct sigio **sigiop; 2645 int sig, checkctty; 2646 { 2647 struct sigio *sigio; 2648 2649 SIGIO_LOCK(); 2650 sigio = *sigiop; 2651 if (sigio == NULL) { 2652 SIGIO_UNLOCK(); 2653 return; 2654 } 2655 if (sigio->sio_pgid > 0) { 2656 PROC_LOCK(sigio->sio_proc); 2657 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred)) 2658 psignal(sigio->sio_proc, sig); 2659 PROC_UNLOCK(sigio->sio_proc); 2660 } else if (sigio->sio_pgid < 0) { 2661 struct proc *p; 2662 2663 PGRP_LOCK(sigio->sio_pgrp); 2664 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) { 2665 PROC_LOCK(p); 2666 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) && 2667 (checkctty == 0 || (p->p_flag & P_CONTROLT))) 2668 psignal(p, sig); 2669 PROC_UNLOCK(p); 2670 } 2671 PGRP_UNLOCK(sigio->sio_pgrp); 2672 } 2673 SIGIO_UNLOCK(); 2674 } 2675 2676 static int 2677 filt_sigattach(struct knote *kn) 2678 { 2679 struct proc *p = curproc; 2680 2681 kn->kn_ptr.p_proc = p; 2682 kn->kn_flags |= EV_CLEAR; /* automatically set */ 2683 2684 PROC_LOCK(p); 2685 SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext); 2686 PROC_UNLOCK(p); 2687 2688 return (0); 2689 } 2690 2691 static void 2692 filt_sigdetach(struct knote *kn) 2693 { 2694 struct proc *p = kn->kn_ptr.p_proc; 2695 2696 PROC_LOCK(p); 2697 SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext); 2698 PROC_UNLOCK(p); 2699 } 2700 2701 /* 2702 * signal knotes are shared with proc knotes, so we apply a mask to 2703 * the hint in order to differentiate them from process hints. This 2704 * could be avoided by using a signal-specific knote list, but probably 2705 * isn't worth the trouble. 2706 */ 2707 static int 2708 filt_signal(struct knote *kn, long hint) 2709 { 2710 2711 if (hint & NOTE_SIGNAL) { 2712 hint &= ~NOTE_SIGNAL; 2713 2714 if (kn->kn_id == hint) 2715 kn->kn_data++; 2716 } 2717 return (kn->kn_data != 0); 2718 } 2719 2720 struct sigacts * 2721 sigacts_alloc(void) 2722 { 2723 struct sigacts *ps; 2724 2725 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO); 2726 ps->ps_refcnt = 1; 2727 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF); 2728 return (ps); 2729 } 2730 2731 void 2732 sigacts_free(struct sigacts *ps) 2733 { 2734 2735 mtx_lock(&ps->ps_mtx); 2736 ps->ps_refcnt--; 2737 if (ps->ps_refcnt == 0) { 2738 mtx_destroy(&ps->ps_mtx); 2739 free(ps, M_SUBPROC); 2740 } else 2741 mtx_unlock(&ps->ps_mtx); 2742 } 2743 2744 struct sigacts * 2745 sigacts_hold(struct sigacts *ps) 2746 { 2747 mtx_lock(&ps->ps_mtx); 2748 ps->ps_refcnt++; 2749 mtx_unlock(&ps->ps_mtx); 2750 return (ps); 2751 } 2752 2753 void 2754 sigacts_copy(struct sigacts *dest, struct sigacts *src) 2755 { 2756 2757 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest")); 2758 mtx_lock(&src->ps_mtx); 2759 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt)); 2760 mtx_unlock(&src->ps_mtx); 2761 } 2762 2763 int 2764 sigacts_shared(struct sigacts *ps) 2765 { 2766 int shared; 2767 2768 mtx_lock(&ps->ps_mtx); 2769 shared = ps->ps_refcnt > 1; 2770 mtx_unlock(&ps->ps_mtx); 2771 return (shared); 2772 } 2773