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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_compat.h" 45 #include "opt_ktrace.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/signalvar.h> 50 #include <sys/vnode.h> 51 #include <sys/acct.h> 52 #include <sys/condvar.h> 53 #include <sys/event.h> 54 #include <sys/fcntl.h> 55 #include <sys/kernel.h> 56 #include <sys/kse.h> 57 #include <sys/ktr.h> 58 #include <sys/ktrace.h> 59 #include <sys/lock.h> 60 #include <sys/malloc.h> 61 #include <sys/mutex.h> 62 #include <sys/namei.h> 63 #include <sys/proc.h> 64 #include <sys/pioctl.h> 65 #include <sys/resourcevar.h> 66 #include <sys/smp.h> 67 #include <sys/stat.h> 68 #include <sys/sx.h> 69 #include <sys/syscallsubr.h> 70 #include <sys/sysctl.h> 71 #include <sys/sysent.h> 72 #include <sys/syslog.h> 73 #include <sys/sysproto.h> 74 #include <sys/unistd.h> 75 #include <sys/wait.h> 76 77 #include <machine/cpu.h> 78 79 #if defined (__alpha__) && !defined(COMPAT_43) 80 #error "You *really* need COMPAT_43 on the alpha for longjmp(3)" 81 #endif 82 83 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */ 84 85 static int coredump(struct thread *); 86 static char *expand_name(const char *, uid_t, pid_t); 87 static int killpg1(struct thread *td, int sig, int pgid, int all); 88 static int issignal(struct thread *p); 89 static int sigprop(int sig); 90 static void stop(struct proc *); 91 static void tdsigwakeup(struct thread *td, int sig, sig_t action); 92 static int filt_sigattach(struct knote *kn); 93 static void filt_sigdetach(struct knote *kn); 94 static int filt_signal(struct knote *kn, long hint); 95 static struct thread *sigtd(struct proc *p, int sig, int prop); 96 static int kern_sigtimedwait(struct thread *td, sigset_t set, 97 siginfo_t *info, struct timespec *timeout); 98 static void do_tdsignal(struct thread *td, int sig, sigtarget_t target); 99 100 struct filterops sig_filtops = 101 { 0, filt_sigattach, filt_sigdetach, filt_signal }; 102 103 static int kern_logsigexit = 1; 104 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW, 105 &kern_logsigexit, 0, 106 "Log processes quitting on abnormal signals to syslog(3)"); 107 108 /* 109 * Policy -- Can ucred cr1 send SIGIO to process cr2? 110 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG 111 * in the right situations. 112 */ 113 #define CANSIGIO(cr1, cr2) \ 114 ((cr1)->cr_uid == 0 || \ 115 (cr1)->cr_ruid == (cr2)->cr_ruid || \ 116 (cr1)->cr_uid == (cr2)->cr_ruid || \ 117 (cr1)->cr_ruid == (cr2)->cr_uid || \ 118 (cr1)->cr_uid == (cr2)->cr_uid) 119 120 int sugid_coredump; 121 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW, 122 &sugid_coredump, 0, "Enable coredumping set user/group ID processes"); 123 124 static int do_coredump = 1; 125 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW, 126 &do_coredump, 0, "Enable/Disable coredumps"); 127 128 /* 129 * Signal properties and actions. 130 * The array below categorizes the signals and their default actions 131 * according to the following properties: 132 */ 133 #define SA_KILL 0x01 /* terminates process by default */ 134 #define SA_CORE 0x02 /* ditto and coredumps */ 135 #define SA_STOP 0x04 /* suspend process */ 136 #define SA_TTYSTOP 0x08 /* ditto, from tty */ 137 #define SA_IGNORE 0x10 /* ignore by default */ 138 #define SA_CONT 0x20 /* continue if suspended */ 139 #define SA_CANTMASK 0x40 /* non-maskable, catchable */ 140 #define SA_PROC 0x80 /* deliverable to any thread */ 141 142 static int sigproptbl[NSIG] = { 143 SA_KILL|SA_PROC, /* SIGHUP */ 144 SA_KILL|SA_PROC, /* SIGINT */ 145 SA_KILL|SA_CORE|SA_PROC, /* SIGQUIT */ 146 SA_KILL|SA_CORE, /* SIGILL */ 147 SA_KILL|SA_CORE, /* SIGTRAP */ 148 SA_KILL|SA_CORE, /* SIGABRT */ 149 SA_KILL|SA_CORE|SA_PROC, /* SIGEMT */ 150 SA_KILL|SA_CORE, /* SIGFPE */ 151 SA_KILL|SA_PROC, /* SIGKILL */ 152 SA_KILL|SA_CORE, /* SIGBUS */ 153 SA_KILL|SA_CORE, /* SIGSEGV */ 154 SA_KILL|SA_CORE, /* SIGSYS */ 155 SA_KILL|SA_PROC, /* SIGPIPE */ 156 SA_KILL|SA_PROC, /* SIGALRM */ 157 SA_KILL|SA_PROC, /* SIGTERM */ 158 SA_IGNORE|SA_PROC, /* SIGURG */ 159 SA_STOP|SA_PROC, /* SIGSTOP */ 160 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTSTP */ 161 SA_IGNORE|SA_CONT|SA_PROC, /* SIGCONT */ 162 SA_IGNORE|SA_PROC, /* SIGCHLD */ 163 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTIN */ 164 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTOU */ 165 SA_IGNORE|SA_PROC, /* SIGIO */ 166 SA_KILL, /* SIGXCPU */ 167 SA_KILL, /* SIGXFSZ */ 168 SA_KILL|SA_PROC, /* SIGVTALRM */ 169 SA_KILL|SA_PROC, /* SIGPROF */ 170 SA_IGNORE|SA_PROC, /* SIGWINCH */ 171 SA_IGNORE|SA_PROC, /* SIGINFO */ 172 SA_KILL|SA_PROC, /* SIGUSR1 */ 173 SA_KILL|SA_PROC, /* SIGUSR2 */ 174 }; 175 176 /* 177 * Determine signal that should be delivered to process p, the current 178 * process, 0 if none. If there is a pending stop signal with default 179 * action, the process stops in issignal(). 180 * XXXKSE the check for a pending stop is not done under KSE 181 * 182 * MP SAFE. 183 */ 184 int 185 cursig(struct thread *td) 186 { 187 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED); 188 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED); 189 mtx_assert(&sched_lock, MA_NOTOWNED); 190 return (SIGPENDING(td) ? issignal(td) : 0); 191 } 192 193 /* 194 * Arrange for ast() to handle unmasked pending signals on return to user 195 * mode. This must be called whenever a signal is added to td_siglist or 196 * unmasked in td_sigmask. 197 */ 198 void 199 signotify(struct thread *td) 200 { 201 struct proc *p; 202 sigset_t set, saved; 203 204 p = td->td_proc; 205 206 PROC_LOCK_ASSERT(p, MA_OWNED); 207 208 /* 209 * If our mask changed we may have to move signal that were 210 * previously masked by all threads to our siglist. 211 */ 212 set = p->p_siglist; 213 if (p->p_flag & P_SA) 214 saved = p->p_siglist; 215 SIGSETNAND(set, td->td_sigmask); 216 SIGSETNAND(p->p_siglist, set); 217 SIGSETOR(td->td_siglist, set); 218 219 if (SIGPENDING(td)) { 220 mtx_lock_spin(&sched_lock); 221 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING; 222 mtx_unlock_spin(&sched_lock); 223 } 224 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) { 225 if (SIGSETEQ(saved, p->p_siglist)) 226 return; 227 else { 228 /* pending set changed */ 229 p->p_flag |= P_SIGEVENT; 230 wakeup(&p->p_siglist); 231 } 232 } 233 } 234 235 int 236 sigonstack(size_t sp) 237 { 238 struct proc *p = curthread->td_proc; 239 240 PROC_LOCK_ASSERT(p, MA_OWNED); 241 return ((p->p_flag & P_ALTSTACK) ? 242 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 243 ((p->p_sigstk.ss_size == 0) ? (p->p_sigstk.ss_flags & SS_ONSTACK) : 244 ((sp - (size_t)p->p_sigstk.ss_sp) < p->p_sigstk.ss_size)) 245 #else 246 ((sp - (size_t)p->p_sigstk.ss_sp) < p->p_sigstk.ss_size) 247 #endif 248 : 0); 249 } 250 251 static __inline int 252 sigprop(int sig) 253 { 254 255 if (sig > 0 && sig < NSIG) 256 return (sigproptbl[_SIG_IDX(sig)]); 257 return (0); 258 } 259 260 int 261 sig_ffs(sigset_t *set) 262 { 263 int i; 264 265 for (i = 0; i < _SIG_WORDS; i++) 266 if (set->__bits[i]) 267 return (ffs(set->__bits[i]) + (i * 32)); 268 return (0); 269 } 270 271 /* 272 * kern_sigaction 273 * sigaction 274 * freebsd4_sigaction 275 * osigaction 276 * 277 * MPSAFE 278 */ 279 int 280 kern_sigaction(td, sig, act, oact, flags) 281 struct thread *td; 282 register int sig; 283 struct sigaction *act, *oact; 284 int flags; 285 { 286 struct sigacts *ps; 287 struct thread *td0; 288 struct proc *p = td->td_proc; 289 290 if (!_SIG_VALID(sig)) 291 return (EINVAL); 292 293 PROC_LOCK(p); 294 ps = p->p_sigacts; 295 mtx_lock(&ps->ps_mtx); 296 if (oact) { 297 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)]; 298 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)]; 299 oact->sa_flags = 0; 300 if (SIGISMEMBER(ps->ps_sigonstack, sig)) 301 oact->sa_flags |= SA_ONSTACK; 302 if (!SIGISMEMBER(ps->ps_sigintr, sig)) 303 oact->sa_flags |= SA_RESTART; 304 if (SIGISMEMBER(ps->ps_sigreset, sig)) 305 oact->sa_flags |= SA_RESETHAND; 306 if (SIGISMEMBER(ps->ps_signodefer, sig)) 307 oact->sa_flags |= SA_NODEFER; 308 if (SIGISMEMBER(ps->ps_siginfo, sig)) 309 oact->sa_flags |= SA_SIGINFO; 310 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP) 311 oact->sa_flags |= SA_NOCLDSTOP; 312 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT) 313 oact->sa_flags |= SA_NOCLDWAIT; 314 } 315 if (act) { 316 if ((sig == SIGKILL || sig == SIGSTOP) && 317 act->sa_handler != SIG_DFL) { 318 mtx_unlock(&ps->ps_mtx); 319 PROC_UNLOCK(p); 320 return (EINVAL); 321 } 322 323 /* 324 * Change setting atomically. 325 */ 326 327 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask; 328 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]); 329 if (act->sa_flags & SA_SIGINFO) { 330 ps->ps_sigact[_SIG_IDX(sig)] = 331 (__sighandler_t *)act->sa_sigaction; 332 SIGADDSET(ps->ps_siginfo, sig); 333 } else { 334 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler; 335 SIGDELSET(ps->ps_siginfo, sig); 336 } 337 if (!(act->sa_flags & SA_RESTART)) 338 SIGADDSET(ps->ps_sigintr, sig); 339 else 340 SIGDELSET(ps->ps_sigintr, sig); 341 if (act->sa_flags & SA_ONSTACK) 342 SIGADDSET(ps->ps_sigonstack, sig); 343 else 344 SIGDELSET(ps->ps_sigonstack, sig); 345 if (act->sa_flags & SA_RESETHAND) 346 SIGADDSET(ps->ps_sigreset, sig); 347 else 348 SIGDELSET(ps->ps_sigreset, sig); 349 if (act->sa_flags & SA_NODEFER) 350 SIGADDSET(ps->ps_signodefer, sig); 351 else 352 SIGDELSET(ps->ps_signodefer, sig); 353 #ifdef COMPAT_SUNOS 354 if (act->sa_flags & SA_USERTRAMP) 355 SIGADDSET(ps->ps_usertramp, sig); 356 else 357 SIGDELSET(ps->ps_usertramp, sig); 358 #endif 359 if (sig == SIGCHLD) { 360 if (act->sa_flags & SA_NOCLDSTOP) 361 ps->ps_flag |= PS_NOCLDSTOP; 362 else 363 ps->ps_flag &= ~PS_NOCLDSTOP; 364 if (act->sa_flags & SA_NOCLDWAIT) { 365 /* 366 * Paranoia: since SA_NOCLDWAIT is implemented 367 * by reparenting the dying child to PID 1 (and 368 * trust it to reap the zombie), PID 1 itself 369 * is forbidden to set SA_NOCLDWAIT. 370 */ 371 if (p->p_pid == 1) 372 ps->ps_flag &= ~PS_NOCLDWAIT; 373 else 374 ps->ps_flag |= PS_NOCLDWAIT; 375 } else 376 ps->ps_flag &= ~PS_NOCLDWAIT; 377 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 378 ps->ps_flag |= PS_CLDSIGIGN; 379 else 380 ps->ps_flag &= ~PS_CLDSIGIGN; 381 } 382 /* 383 * Set bit in ps_sigignore for signals that are set to SIG_IGN, 384 * and for signals set to SIG_DFL where the default is to 385 * ignore. However, don't put SIGCONT in ps_sigignore, as we 386 * have to restart the process. 387 */ 388 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 389 (sigprop(sig) & SA_IGNORE && 390 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) { 391 if ((p->p_flag & P_SA) && 392 SIGISMEMBER(p->p_siglist, sig)) { 393 p->p_flag |= P_SIGEVENT; 394 wakeup(&p->p_siglist); 395 } 396 /* never to be seen again */ 397 SIGDELSET(p->p_siglist, sig); 398 FOREACH_THREAD_IN_PROC(p, td0) 399 SIGDELSET(td0->td_siglist, sig); 400 if (sig != SIGCONT) 401 /* easier in psignal */ 402 SIGADDSET(ps->ps_sigignore, sig); 403 SIGDELSET(ps->ps_sigcatch, sig); 404 } else { 405 SIGDELSET(ps->ps_sigignore, sig); 406 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL) 407 SIGDELSET(ps->ps_sigcatch, sig); 408 else 409 SIGADDSET(ps->ps_sigcatch, sig); 410 } 411 #ifdef COMPAT_FREEBSD4 412 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 413 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 414 (flags & KSA_FREEBSD4) == 0) 415 SIGDELSET(ps->ps_freebsd4, sig); 416 else 417 SIGADDSET(ps->ps_freebsd4, sig); 418 #endif 419 #ifdef COMPAT_43 420 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 421 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || 422 (flags & KSA_OSIGSET) == 0) 423 SIGDELSET(ps->ps_osigset, sig); 424 else 425 SIGADDSET(ps->ps_osigset, sig); 426 #endif 427 } 428 mtx_unlock(&ps->ps_mtx); 429 PROC_UNLOCK(p); 430 return (0); 431 } 432 433 #ifndef _SYS_SYSPROTO_H_ 434 struct sigaction_args { 435 int sig; 436 struct sigaction *act; 437 struct sigaction *oact; 438 }; 439 #endif 440 /* 441 * MPSAFE 442 */ 443 int 444 sigaction(td, uap) 445 struct thread *td; 446 register struct sigaction_args *uap; 447 { 448 struct sigaction act, oact; 449 register struct sigaction *actp, *oactp; 450 int error; 451 452 actp = (uap->act != NULL) ? &act : NULL; 453 oactp = (uap->oact != NULL) ? &oact : NULL; 454 if (actp) { 455 error = copyin(uap->act, actp, sizeof(act)); 456 if (error) 457 return (error); 458 } 459 error = kern_sigaction(td, uap->sig, actp, oactp, 0); 460 if (oactp && !error) 461 error = copyout(oactp, uap->oact, sizeof(oact)); 462 return (error); 463 } 464 465 #ifdef COMPAT_FREEBSD4 466 #ifndef _SYS_SYSPROTO_H_ 467 struct freebsd4_sigaction_args { 468 int sig; 469 struct sigaction *act; 470 struct sigaction *oact; 471 }; 472 #endif 473 /* 474 * MPSAFE 475 */ 476 int 477 freebsd4_sigaction(td, uap) 478 struct thread *td; 479 register struct freebsd4_sigaction_args *uap; 480 { 481 struct sigaction act, oact; 482 register struct sigaction *actp, *oactp; 483 int error; 484 485 486 actp = (uap->act != NULL) ? &act : NULL; 487 oactp = (uap->oact != NULL) ? &oact : NULL; 488 if (actp) { 489 error = copyin(uap->act, actp, sizeof(act)); 490 if (error) 491 return (error); 492 } 493 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4); 494 if (oactp && !error) 495 error = copyout(oactp, uap->oact, sizeof(oact)); 496 return (error); 497 } 498 #endif /* COMAPT_FREEBSD4 */ 499 500 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 501 #ifndef _SYS_SYSPROTO_H_ 502 struct osigaction_args { 503 int signum; 504 struct osigaction *nsa; 505 struct osigaction *osa; 506 }; 507 #endif 508 /* 509 * MPSAFE 510 */ 511 int 512 osigaction(td, uap) 513 struct thread *td; 514 register struct osigaction_args *uap; 515 { 516 struct osigaction sa; 517 struct sigaction nsa, osa; 518 register struct sigaction *nsap, *osap; 519 int error; 520 521 if (uap->signum <= 0 || uap->signum >= ONSIG) 522 return (EINVAL); 523 524 nsap = (uap->nsa != NULL) ? &nsa : NULL; 525 osap = (uap->osa != NULL) ? &osa : NULL; 526 527 if (nsap) { 528 error = copyin(uap->nsa, &sa, sizeof(sa)); 529 if (error) 530 return (error); 531 nsap->sa_handler = sa.sa_handler; 532 nsap->sa_flags = sa.sa_flags; 533 OSIG2SIG(sa.sa_mask, nsap->sa_mask); 534 } 535 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 536 if (osap && !error) { 537 sa.sa_handler = osap->sa_handler; 538 sa.sa_flags = osap->sa_flags; 539 SIG2OSIG(osap->sa_mask, sa.sa_mask); 540 error = copyout(&sa, uap->osa, sizeof(sa)); 541 } 542 return (error); 543 } 544 545 #if !defined(__i386__) && !defined(__alpha__) 546 /* Avoid replicating the same stub everywhere */ 547 int 548 osigreturn(td, uap) 549 struct thread *td; 550 struct osigreturn_args *uap; 551 { 552 553 return (nosys(td, (struct nosys_args *)uap)); 554 } 555 #endif 556 #endif /* COMPAT_43 */ 557 558 /* 559 * Initialize signal state for process 0; 560 * set to ignore signals that are ignored by default. 561 */ 562 void 563 siginit(p) 564 struct proc *p; 565 { 566 register int i; 567 struct sigacts *ps; 568 569 PROC_LOCK(p); 570 ps = p->p_sigacts; 571 mtx_lock(&ps->ps_mtx); 572 for (i = 1; i <= NSIG; i++) 573 if (sigprop(i) & SA_IGNORE && i != SIGCONT) 574 SIGADDSET(ps->ps_sigignore, i); 575 mtx_unlock(&ps->ps_mtx); 576 PROC_UNLOCK(p); 577 } 578 579 /* 580 * Reset signals for an exec of the specified process. 581 */ 582 void 583 execsigs(p) 584 register struct proc *p; 585 { 586 register struct sigacts *ps; 587 register int sig; 588 589 /* 590 * Reset caught signals. Held signals remain held 591 * through td_sigmask (unless they were caught, 592 * and are now ignored by default). 593 */ 594 PROC_LOCK_ASSERT(p, MA_OWNED); 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(FIRST_THREAD_IN_PROC(p)->td_siglist, sig); 608 } 609 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 610 } 611 /* 612 * Clear out the td's sigmask. Normal processes use the proc sigmask. 613 */ 614 SIGEMPTYSET(FIRST_THREAD_IN_PROC(p)->td_sigmask); 615 /* 616 * Reset stack state to the user stack. 617 * Clear set of signals caught on the signal stack. 618 */ 619 p->p_sigstk.ss_flags = SS_DISABLE; 620 p->p_sigstk.ss_size = 0; 621 p->p_sigstk.ss_sp = 0; 622 p->p_flag &= ~P_ALTSTACK; 623 /* 624 * Reset no zombies if child dies flag as Solaris does. 625 */ 626 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN); 627 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 628 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL; 629 mtx_unlock(&ps->ps_mtx); 630 } 631 632 /* 633 * kern_sigprocmask() 634 * 635 * Manipulate signal mask. 636 */ 637 int 638 kern_sigprocmask(td, how, set, oset, old) 639 struct thread *td; 640 int how; 641 sigset_t *set, *oset; 642 int old; 643 { 644 int error; 645 646 PROC_LOCK(td->td_proc); 647 if (oset != NULL) 648 *oset = td->td_sigmask; 649 650 error = 0; 651 if (set != NULL) { 652 switch (how) { 653 case SIG_BLOCK: 654 SIG_CANTMASK(*set); 655 SIGSETOR(td->td_sigmask, *set); 656 break; 657 case SIG_UNBLOCK: 658 SIGSETNAND(td->td_sigmask, *set); 659 signotify(td); 660 break; 661 case SIG_SETMASK: 662 SIG_CANTMASK(*set); 663 if (old) 664 SIGSETLO(td->td_sigmask, *set); 665 else 666 td->td_sigmask = *set; 667 signotify(td); 668 break; 669 default: 670 error = EINVAL; 671 break; 672 } 673 } 674 PROC_UNLOCK(td->td_proc); 675 return (error); 676 } 677 678 /* 679 * sigprocmask() - MP SAFE 680 */ 681 682 #ifndef _SYS_SYSPROTO_H_ 683 struct sigprocmask_args { 684 int how; 685 const sigset_t *set; 686 sigset_t *oset; 687 }; 688 #endif 689 int 690 sigprocmask(td, uap) 691 register struct thread *td; 692 struct sigprocmask_args *uap; 693 { 694 sigset_t set, oset; 695 sigset_t *setp, *osetp; 696 int error; 697 698 setp = (uap->set != NULL) ? &set : NULL; 699 osetp = (uap->oset != NULL) ? &oset : NULL; 700 if (setp) { 701 error = copyin(uap->set, setp, sizeof(set)); 702 if (error) 703 return (error); 704 } 705 error = kern_sigprocmask(td, uap->how, setp, osetp, 0); 706 if (osetp && !error) { 707 error = copyout(osetp, uap->oset, sizeof(oset)); 708 } 709 return (error); 710 } 711 712 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 713 /* 714 * osigprocmask() - MP SAFE 715 */ 716 #ifndef _SYS_SYSPROTO_H_ 717 struct osigprocmask_args { 718 int how; 719 osigset_t mask; 720 }; 721 #endif 722 int 723 osigprocmask(td, uap) 724 register struct thread *td; 725 struct osigprocmask_args *uap; 726 { 727 sigset_t set, oset; 728 int error; 729 730 OSIG2SIG(uap->mask, set); 731 error = kern_sigprocmask(td, uap->how, &set, &oset, 1); 732 SIG2OSIG(oset, td->td_retval[0]); 733 return (error); 734 } 735 #endif /* COMPAT_43 */ 736 737 #ifndef _SYS_SYSPROTO_H_ 738 struct sigpending_args { 739 sigset_t *set; 740 }; 741 #endif 742 /* 743 * MPSAFE 744 */ 745 int 746 sigwait(struct thread *td, struct sigwait_args *uap) 747 { 748 siginfo_t info; 749 sigset_t set; 750 int error; 751 752 error = copyin(uap->set, &set, sizeof(set)); 753 if (error) 754 return (error); 755 756 error = kern_sigtimedwait(td, set, &info, NULL); 757 if (error) 758 return (error); 759 760 error = copyout(&info.si_signo, uap->sig, sizeof(info.si_signo)); 761 /* Repost if we got an error. */ 762 if (error && info.si_signo) { 763 PROC_LOCK(td->td_proc); 764 tdsignal(td, info.si_signo, SIGTARGET_TD); 765 PROC_UNLOCK(td->td_proc); 766 } 767 return (error); 768 } 769 /* 770 * MPSAFE 771 */ 772 int 773 sigtimedwait(struct thread *td, struct sigtimedwait_args *uap) 774 { 775 struct timespec ts; 776 struct timespec *timeout; 777 sigset_t set; 778 siginfo_t info; 779 int error; 780 781 if (uap->timeout) { 782 error = copyin(uap->timeout, &ts, sizeof(ts)); 783 if (error) 784 return (error); 785 786 timeout = &ts; 787 } else 788 timeout = NULL; 789 790 error = copyin(uap->set, &set, sizeof(set)); 791 if (error) 792 return (error); 793 794 error = kern_sigtimedwait(td, set, &info, timeout); 795 if (error) 796 return (error); 797 798 if (uap->info) 799 error = copyout(&info, uap->info, sizeof(info)); 800 /* Repost if we got an error. */ 801 if (error && info.si_signo) { 802 PROC_LOCK(td->td_proc); 803 tdsignal(td, info.si_signo, SIGTARGET_TD); 804 PROC_UNLOCK(td->td_proc); 805 } else { 806 td->td_retval[0] = info.si_signo; 807 } 808 return (error); 809 } 810 811 /* 812 * MPSAFE 813 */ 814 int 815 sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap) 816 { 817 siginfo_t info; 818 sigset_t set; 819 int error; 820 821 error = copyin(uap->set, &set, sizeof(set)); 822 if (error) 823 return (error); 824 825 error = kern_sigtimedwait(td, set, &info, NULL); 826 if (error) 827 return (error); 828 829 if (uap->info) 830 error = copyout(&info, uap->info, sizeof(info)); 831 /* Repost if we got an error. */ 832 if (error && info.si_signo) { 833 PROC_LOCK(td->td_proc); 834 tdsignal(td, info.si_signo, SIGTARGET_TD); 835 PROC_UNLOCK(td->td_proc); 836 } else { 837 td->td_retval[0] = info.si_signo; 838 } 839 return (error); 840 } 841 842 static int 843 kern_sigtimedwait(struct thread *td, sigset_t set, siginfo_t *info, 844 struct timespec *timeout) 845 { 846 register struct sigacts *ps; 847 sigset_t oldmask; 848 struct proc *p; 849 int error; 850 int sig; 851 int hz; 852 853 p = td->td_proc; 854 error = 0; 855 sig = 0; 856 SIG_CANTMASK(set); 857 858 PROC_LOCK(p); 859 ps = p->p_sigacts; 860 oldmask = td->td_sigmask; 861 SIGFILLSET(td->td_sigmask); 862 SIG_CANTMASK(td->td_sigmask); 863 SIGSETNAND(td->td_sigmask, set); 864 signotify(td); 865 866 mtx_lock(&ps->ps_mtx); 867 sig = cursig(td); 868 if (sig) 869 goto out; 870 871 /* 872 * POSIX says this must be checked after looking for pending 873 * signals. 874 */ 875 if (timeout) { 876 struct timeval tv; 877 878 if (timeout->tv_nsec > 1000000000) { 879 error = EINVAL; 880 goto out; 881 } 882 if (timeout->tv_sec == 0 && timeout->tv_nsec == 0) 883 goto nosleep; 884 TIMESPEC_TO_TIMEVAL(&tv, timeout); 885 hz = tvtohz(&tv); 886 } else 887 hz = 0; 888 889 mtx_unlock(&ps->ps_mtx); 890 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "pause", hz); 891 mtx_lock(&ps->ps_mtx); 892 if (error == EINTR) 893 error = 0; 894 else if (error) 895 goto out; 896 nosleep: 897 sig = cursig(td); 898 899 out: 900 td->td_sigmask = oldmask; 901 if (sig) { 902 sig_t action; 903 904 action = ps->ps_sigact[_SIG_IDX(sig)]; 905 mtx_unlock(&ps->ps_mtx); 906 #ifdef KTRACE 907 if (KTRPOINT(td, KTR_PSIG)) 908 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ? 909 &td->td_oldsigmask : &td->td_sigmask, 0); 910 #endif 911 _STOPEVENT(p, S_SIG, sig); 912 913 if (action == SIG_DFL) 914 sigexit(td, sig); 915 /* NOTREACHED */ 916 917 SIGDELSET(td->td_siglist, sig); 918 info->si_signo = sig; 919 info->si_code = 0; 920 } else 921 mtx_unlock(&ps->ps_mtx); 922 PROC_UNLOCK(p); 923 return (error); 924 } 925 926 /* 927 * MPSAFE 928 */ 929 int 930 sigpending(td, uap) 931 struct thread *td; 932 struct sigpending_args *uap; 933 { 934 struct proc *p = td->td_proc; 935 sigset_t siglist; 936 937 PROC_LOCK(p); 938 siglist = p->p_siglist; 939 SIGSETOR(siglist, td->td_siglist); 940 PROC_UNLOCK(p); 941 return (copyout(&siglist, uap->set, sizeof(sigset_t))); 942 } 943 944 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 945 #ifndef _SYS_SYSPROTO_H_ 946 struct osigpending_args { 947 int dummy; 948 }; 949 #endif 950 /* 951 * MPSAFE 952 */ 953 int 954 osigpending(td, uap) 955 struct thread *td; 956 struct osigpending_args *uap; 957 { 958 struct proc *p = td->td_proc; 959 sigset_t siglist; 960 961 PROC_LOCK(p); 962 siglist = p->p_siglist; 963 SIGSETOR(siglist, td->td_siglist); 964 PROC_UNLOCK(p); 965 SIG2OSIG(siglist, td->td_retval[0]); 966 return (0); 967 } 968 #endif /* COMPAT_43 */ 969 970 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 971 /* 972 * Generalized interface signal handler, 4.3-compatible. 973 */ 974 #ifndef _SYS_SYSPROTO_H_ 975 struct osigvec_args { 976 int signum; 977 struct sigvec *nsv; 978 struct sigvec *osv; 979 }; 980 #endif 981 /* 982 * MPSAFE 983 */ 984 /* ARGSUSED */ 985 int 986 osigvec(td, uap) 987 struct thread *td; 988 register struct osigvec_args *uap; 989 { 990 struct sigvec vec; 991 struct sigaction nsa, osa; 992 register struct sigaction *nsap, *osap; 993 int error; 994 995 if (uap->signum <= 0 || uap->signum >= ONSIG) 996 return (EINVAL); 997 nsap = (uap->nsv != NULL) ? &nsa : NULL; 998 osap = (uap->osv != NULL) ? &osa : NULL; 999 if (nsap) { 1000 error = copyin(uap->nsv, &vec, sizeof(vec)); 1001 if (error) 1002 return (error); 1003 nsap->sa_handler = vec.sv_handler; 1004 OSIG2SIG(vec.sv_mask, nsap->sa_mask); 1005 nsap->sa_flags = vec.sv_flags; 1006 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */ 1007 #ifdef COMPAT_SUNOS 1008 nsap->sa_flags |= SA_USERTRAMP; 1009 #endif 1010 } 1011 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET); 1012 if (osap && !error) { 1013 vec.sv_handler = osap->sa_handler; 1014 SIG2OSIG(osap->sa_mask, vec.sv_mask); 1015 vec.sv_flags = osap->sa_flags; 1016 vec.sv_flags &= ~SA_NOCLDWAIT; 1017 vec.sv_flags ^= SA_RESTART; 1018 #ifdef COMPAT_SUNOS 1019 vec.sv_flags &= ~SA_NOCLDSTOP; 1020 #endif 1021 error = copyout(&vec, uap->osv, sizeof(vec)); 1022 } 1023 return (error); 1024 } 1025 1026 #ifndef _SYS_SYSPROTO_H_ 1027 struct osigblock_args { 1028 int mask; 1029 }; 1030 #endif 1031 /* 1032 * MPSAFE 1033 */ 1034 int 1035 osigblock(td, uap) 1036 register struct thread *td; 1037 struct osigblock_args *uap; 1038 { 1039 struct proc *p = td->td_proc; 1040 sigset_t set; 1041 1042 OSIG2SIG(uap->mask, set); 1043 SIG_CANTMASK(set); 1044 PROC_LOCK(p); 1045 SIG2OSIG(td->td_sigmask, td->td_retval[0]); 1046 SIGSETOR(td->td_sigmask, set); 1047 PROC_UNLOCK(p); 1048 return (0); 1049 } 1050 1051 #ifndef _SYS_SYSPROTO_H_ 1052 struct osigsetmask_args { 1053 int mask; 1054 }; 1055 #endif 1056 /* 1057 * MPSAFE 1058 */ 1059 int 1060 osigsetmask(td, uap) 1061 struct thread *td; 1062 struct osigsetmask_args *uap; 1063 { 1064 struct proc *p = td->td_proc; 1065 sigset_t set; 1066 1067 OSIG2SIG(uap->mask, set); 1068 SIG_CANTMASK(set); 1069 PROC_LOCK(p); 1070 SIG2OSIG(td->td_sigmask, td->td_retval[0]); 1071 SIGSETLO(td->td_sigmask, set); 1072 signotify(td); 1073 PROC_UNLOCK(p); 1074 return (0); 1075 } 1076 #endif /* COMPAT_43 || COMPAT_SUNOS */ 1077 1078 /* 1079 * Suspend process until signal, providing mask to be set 1080 * in the meantime. Note nonstandard calling convention: 1081 * libc stub passes mask, not pointer, to save a copyin. 1082 ***** XXXKSE this doesn't make sense under KSE. 1083 ***** Do we suspend the thread or all threads in the process? 1084 ***** How do we suspend threads running NOW on another processor? 1085 */ 1086 #ifndef _SYS_SYSPROTO_H_ 1087 struct sigsuspend_args { 1088 const sigset_t *sigmask; 1089 }; 1090 #endif 1091 /* 1092 * MPSAFE 1093 */ 1094 /* ARGSUSED */ 1095 int 1096 sigsuspend(td, uap) 1097 struct thread *td; 1098 struct sigsuspend_args *uap; 1099 { 1100 sigset_t mask; 1101 int error; 1102 1103 error = copyin(uap->sigmask, &mask, sizeof(mask)); 1104 if (error) 1105 return (error); 1106 return (kern_sigsuspend(td, mask)); 1107 } 1108 1109 int 1110 kern_sigsuspend(struct thread *td, sigset_t mask) 1111 { 1112 struct proc *p = td->td_proc; 1113 1114 /* 1115 * When returning from sigsuspend, we want 1116 * the old mask to be restored after the 1117 * signal handler has finished. Thus, we 1118 * save it here and mark the sigacts structure 1119 * to indicate this. 1120 */ 1121 PROC_LOCK(p); 1122 td->td_oldsigmask = td->td_sigmask; 1123 td->td_pflags |= TDP_OLDMASK; 1124 SIG_CANTMASK(mask); 1125 td->td_sigmask = mask; 1126 signotify(td); 1127 while (msleep(p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0) 1128 /* void */; 1129 PROC_UNLOCK(p); 1130 /* always return EINTR rather than ERESTART... */ 1131 return (EINTR); 1132 } 1133 1134 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 1135 #ifndef _SYS_SYSPROTO_H_ 1136 struct osigsuspend_args { 1137 osigset_t mask; 1138 }; 1139 #endif 1140 /* 1141 * MPSAFE 1142 */ 1143 /* ARGSUSED */ 1144 int 1145 osigsuspend(td, uap) 1146 struct thread *td; 1147 struct osigsuspend_args *uap; 1148 { 1149 struct proc *p = td->td_proc; 1150 sigset_t mask; 1151 1152 PROC_LOCK(p); 1153 td->td_oldsigmask = td->td_sigmask; 1154 td->td_pflags |= TDP_OLDMASK; 1155 OSIG2SIG(uap->mask, mask); 1156 SIG_CANTMASK(mask); 1157 SIGSETLO(td->td_sigmask, mask); 1158 signotify(td); 1159 while (msleep(p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0) 1160 /* void */; 1161 PROC_UNLOCK(p); 1162 /* always return EINTR rather than ERESTART... */ 1163 return (EINTR); 1164 } 1165 #endif /* COMPAT_43 */ 1166 1167 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 1168 #ifndef _SYS_SYSPROTO_H_ 1169 struct osigstack_args { 1170 struct sigstack *nss; 1171 struct sigstack *oss; 1172 }; 1173 #endif 1174 /* 1175 * MPSAFE 1176 */ 1177 /* ARGSUSED */ 1178 int 1179 osigstack(td, uap) 1180 struct thread *td; 1181 register struct osigstack_args *uap; 1182 { 1183 struct proc *p = td->td_proc; 1184 struct sigstack nss, oss; 1185 int error = 0; 1186 1187 if (uap->nss != NULL) { 1188 error = copyin(uap->nss, &nss, sizeof(nss)); 1189 if (error) 1190 return (error); 1191 } 1192 PROC_LOCK(p); 1193 oss.ss_sp = p->p_sigstk.ss_sp; 1194 oss.ss_onstack = sigonstack(cpu_getstack(td)); 1195 if (uap->nss != NULL) { 1196 p->p_sigstk.ss_sp = nss.ss_sp; 1197 p->p_sigstk.ss_size = 0; 1198 p->p_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK; 1199 p->p_flag |= P_ALTSTACK; 1200 } 1201 PROC_UNLOCK(p); 1202 if (uap->oss != NULL) 1203 error = copyout(&oss, uap->oss, sizeof(oss)); 1204 1205 return (error); 1206 } 1207 #endif /* COMPAT_43 || COMPAT_SUNOS */ 1208 1209 #ifndef _SYS_SYSPROTO_H_ 1210 struct sigaltstack_args { 1211 stack_t *ss; 1212 stack_t *oss; 1213 }; 1214 #endif 1215 /* 1216 * MPSAFE 1217 */ 1218 /* ARGSUSED */ 1219 int 1220 sigaltstack(td, uap) 1221 struct thread *td; 1222 register struct sigaltstack_args *uap; 1223 { 1224 stack_t ss, oss; 1225 int error; 1226 1227 if (uap->ss != NULL) { 1228 error = copyin(uap->ss, &ss, sizeof(ss)); 1229 if (error) 1230 return (error); 1231 } 1232 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL, 1233 (uap->oss != NULL) ? &oss : NULL); 1234 if (error) 1235 return (error); 1236 if (uap->oss != NULL) 1237 error = copyout(&oss, uap->oss, sizeof(stack_t)); 1238 return (error); 1239 } 1240 1241 int 1242 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss) 1243 { 1244 struct proc *p = td->td_proc; 1245 int oonstack; 1246 1247 PROC_LOCK(p); 1248 oonstack = sigonstack(cpu_getstack(td)); 1249 1250 if (oss != NULL) { 1251 *oss = p->p_sigstk; 1252 oss->ss_flags = (p->p_flag & P_ALTSTACK) 1253 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; 1254 } 1255 1256 if (ss != NULL) { 1257 if (oonstack) { 1258 PROC_UNLOCK(p); 1259 return (EPERM); 1260 } 1261 if ((ss->ss_flags & ~SS_DISABLE) != 0) { 1262 PROC_UNLOCK(p); 1263 return (EINVAL); 1264 } 1265 if (!(ss->ss_flags & SS_DISABLE)) { 1266 if (ss->ss_size < p->p_sysent->sv_minsigstksz) { 1267 PROC_UNLOCK(p); 1268 return (ENOMEM); 1269 } 1270 p->p_sigstk = *ss; 1271 p->p_flag |= P_ALTSTACK; 1272 } else { 1273 p->p_flag &= ~P_ALTSTACK; 1274 } 1275 } 1276 PROC_UNLOCK(p); 1277 return (0); 1278 } 1279 1280 /* 1281 * Common code for kill process group/broadcast kill. 1282 * cp is calling process. 1283 */ 1284 static int 1285 killpg1(td, sig, pgid, all) 1286 register struct thread *td; 1287 int sig, pgid, all; 1288 { 1289 register struct proc *p; 1290 struct pgrp *pgrp; 1291 int nfound = 0; 1292 1293 if (all) { 1294 /* 1295 * broadcast 1296 */ 1297 sx_slock(&allproc_lock); 1298 LIST_FOREACH(p, &allproc, p_list) { 1299 PROC_LOCK(p); 1300 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || 1301 p == td->td_proc) { 1302 PROC_UNLOCK(p); 1303 continue; 1304 } 1305 if (p_cansignal(td, p, sig) == 0) { 1306 nfound++; 1307 if (sig) 1308 psignal(p, sig); 1309 } 1310 PROC_UNLOCK(p); 1311 } 1312 sx_sunlock(&allproc_lock); 1313 } else { 1314 sx_slock(&proctree_lock); 1315 if (pgid == 0) { 1316 /* 1317 * zero pgid means send to my process group. 1318 */ 1319 pgrp = td->td_proc->p_pgrp; 1320 PGRP_LOCK(pgrp); 1321 } else { 1322 pgrp = pgfind(pgid); 1323 if (pgrp == NULL) { 1324 sx_sunlock(&proctree_lock); 1325 return (ESRCH); 1326 } 1327 } 1328 sx_sunlock(&proctree_lock); 1329 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1330 PROC_LOCK(p); 1331 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM) { 1332 PROC_UNLOCK(p); 1333 continue; 1334 } 1335 if (p->p_state == PRS_ZOMBIE) { 1336 PROC_UNLOCK(p); 1337 continue; 1338 } 1339 if (p_cansignal(td, p, sig) == 0) { 1340 nfound++; 1341 if (sig) 1342 psignal(p, sig); 1343 } 1344 PROC_UNLOCK(p); 1345 } 1346 PGRP_UNLOCK(pgrp); 1347 } 1348 return (nfound ? 0 : ESRCH); 1349 } 1350 1351 #ifndef _SYS_SYSPROTO_H_ 1352 struct kill_args { 1353 int pid; 1354 int signum; 1355 }; 1356 #endif 1357 /* 1358 * MPSAFE 1359 */ 1360 /* ARGSUSED */ 1361 int 1362 kill(td, uap) 1363 register struct thread *td; 1364 register struct kill_args *uap; 1365 { 1366 register struct proc *p; 1367 int error; 1368 1369 if ((u_int)uap->signum > _SIG_MAXSIG) 1370 return (EINVAL); 1371 1372 if (uap->pid > 0) { 1373 /* kill single process */ 1374 if ((p = pfind(uap->pid)) == NULL) 1375 return (ESRCH); 1376 error = p_cansignal(td, p, uap->signum); 1377 if (error == 0 && uap->signum) 1378 psignal(p, uap->signum); 1379 PROC_UNLOCK(p); 1380 return (error); 1381 } 1382 switch (uap->pid) { 1383 case -1: /* broadcast signal */ 1384 return (killpg1(td, uap->signum, 0, 1)); 1385 case 0: /* signal own process group */ 1386 return (killpg1(td, uap->signum, 0, 0)); 1387 default: /* negative explicit process group */ 1388 return (killpg1(td, uap->signum, -uap->pid, 0)); 1389 } 1390 /* NOTREACHED */ 1391 } 1392 1393 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 1394 #ifndef _SYS_SYSPROTO_H_ 1395 struct okillpg_args { 1396 int pgid; 1397 int signum; 1398 }; 1399 #endif 1400 /* 1401 * MPSAFE 1402 */ 1403 /* ARGSUSED */ 1404 int 1405 okillpg(td, uap) 1406 struct thread *td; 1407 register struct okillpg_args *uap; 1408 { 1409 1410 if ((u_int)uap->signum > _SIG_MAXSIG) 1411 return (EINVAL); 1412 return (killpg1(td, uap->signum, uap->pgid, 0)); 1413 } 1414 #endif /* COMPAT_43 || COMPAT_SUNOS */ 1415 1416 /* 1417 * Send a signal to a process group. 1418 */ 1419 void 1420 gsignal(pgid, sig) 1421 int pgid, sig; 1422 { 1423 struct pgrp *pgrp; 1424 1425 if (pgid != 0) { 1426 sx_slock(&proctree_lock); 1427 pgrp = pgfind(pgid); 1428 sx_sunlock(&proctree_lock); 1429 if (pgrp != NULL) { 1430 pgsignal(pgrp, sig, 0); 1431 PGRP_UNLOCK(pgrp); 1432 } 1433 } 1434 } 1435 1436 /* 1437 * Send a signal to a process group. If checktty is 1, 1438 * limit to members which have a controlling terminal. 1439 */ 1440 void 1441 pgsignal(pgrp, sig, checkctty) 1442 struct pgrp *pgrp; 1443 int sig, checkctty; 1444 { 1445 register struct proc *p; 1446 1447 if (pgrp) { 1448 PGRP_LOCK_ASSERT(pgrp, MA_OWNED); 1449 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1450 PROC_LOCK(p); 1451 if (checkctty == 0 || p->p_flag & P_CONTROLT) 1452 psignal(p, sig); 1453 PROC_UNLOCK(p); 1454 } 1455 } 1456 } 1457 1458 /* 1459 * Send a signal caused by a trap to the current thread. 1460 * If it will be caught immediately, deliver it with correct code. 1461 * Otherwise, post it normally. 1462 * 1463 * MPSAFE 1464 */ 1465 void 1466 trapsignal(struct thread *td, int sig, u_long code) 1467 { 1468 struct sigacts *ps; 1469 struct proc *p; 1470 siginfo_t siginfo; 1471 int error; 1472 1473 p = td->td_proc; 1474 if (td->td_flags & TDF_SA) { 1475 thread_user_enter(p, td); 1476 PROC_LOCK(p); 1477 if (td->td_mailbox) { 1478 SIGDELSET(td->td_sigmask, sig); 1479 mtx_lock_spin(&sched_lock); 1480 /* 1481 * don't psignal to the thread, it only can accept 1482 * its own sync signal. 1483 */ 1484 td->td_flags |= TDF_NOSIGPOST; 1485 /* 1486 * Force scheduling an upcall, so UTS has chance to 1487 * process the signal before thread runs again in 1488 * userland. 1489 */ 1490 if (td->td_upcall) 1491 td->td_upcall->ku_flags |= KUF_DOUPCALL; 1492 mtx_unlock_spin(&sched_lock); 1493 } 1494 } else { 1495 PROC_LOCK(p); 1496 } 1497 ps = p->p_sigacts; 1498 mtx_lock(&ps->ps_mtx); 1499 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) && 1500 !SIGISMEMBER(td->td_sigmask, sig)) { 1501 p->p_stats->p_ru.ru_nsignals++; 1502 #ifdef KTRACE 1503 if (KTRPOINT(curthread, KTR_PSIG)) 1504 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)], 1505 &td->td_sigmask, code); 1506 #endif 1507 if (!(td->td_flags & TDF_SA)) 1508 (*p->p_sysent->sv_sendsig)( 1509 ps->ps_sigact[_SIG_IDX(sig)], sig, 1510 &td->td_sigmask, code); 1511 else { 1512 thread_siginfo(sig, code, &siginfo); 1513 mtx_unlock(&ps->ps_mtx); 1514 PROC_UNLOCK(p); 1515 error = copyout(&siginfo, &td->td_mailbox->tm_syncsig, 1516 sizeof(siginfo)); 1517 PROC_LOCK(p); 1518 if (error) 1519 sigexit(td, SIGILL); 1520 SIGADDSET(td->td_sigmask, sig); 1521 mtx_lock(&ps->ps_mtx); 1522 } 1523 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 1524 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 1525 SIGADDSET(td->td_sigmask, sig); 1526 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 1527 /* 1528 * See kern_sigaction() for origin of this code. 1529 */ 1530 SIGDELSET(ps->ps_sigcatch, sig); 1531 if (sig != SIGCONT && 1532 sigprop(sig) & SA_IGNORE) 1533 SIGADDSET(ps->ps_sigignore, sig); 1534 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 1535 } 1536 mtx_unlock(&ps->ps_mtx); 1537 } else { 1538 mtx_unlock(&ps->ps_mtx); 1539 p->p_code = code; /* XXX for core dump/debugger */ 1540 p->p_sig = sig; /* XXX to verify code */ 1541 tdsignal(td, sig, SIGTARGET_TD); 1542 } 1543 PROC_UNLOCK(p); 1544 } 1545 1546 static struct thread * 1547 sigtd(struct proc *p, int sig, int prop) 1548 { 1549 struct thread *td; 1550 1551 PROC_LOCK_ASSERT(p, MA_OWNED); 1552 1553 /* 1554 * If we know the signal is bound for a specific thread then we 1555 * assume that we are in that threads context. This is the case 1556 * for SIGXCPU, SIGILL, etc. Otherwise someone did a kill() from 1557 * userland and the real thread doesn't actually matter. 1558 */ 1559 if ((prop & SA_PROC) != 0 && curthread->td_proc == p) 1560 return (curthread); 1561 1562 /* 1563 * We should search for the first thread that is blocked in 1564 * sigsuspend with this signal unmasked. 1565 */ 1566 1567 /* XXX */ 1568 1569 /* 1570 * Find the first thread in the proc that doesn't have this signal 1571 * masked. 1572 */ 1573 FOREACH_THREAD_IN_PROC(p, td) 1574 if (!SIGISMEMBER(td->td_sigmask, sig) && 1575 !(td->td_flags & TDF_NOSIGPOST)) 1576 return (td); 1577 1578 return (FIRST_THREAD_IN_PROC(p)); 1579 } 1580 1581 /* 1582 * Send the signal to the process. If the signal has an action, the action 1583 * is usually performed by the target process rather than the caller; we add 1584 * the signal to the set of pending signals for the process. 1585 * 1586 * Exceptions: 1587 * o When a stop signal is sent to a sleeping process that takes the 1588 * default action, the process is stopped without awakening it. 1589 * o SIGCONT restarts stopped processes (or puts them back to sleep) 1590 * regardless of the signal action (eg, blocked or ignored). 1591 * 1592 * Other ignored signals are discarded immediately. 1593 * 1594 * MPSAFE 1595 */ 1596 void 1597 psignal(struct proc *p, int sig) 1598 { 1599 struct thread *td; 1600 int prop; 1601 1602 PROC_LOCK_ASSERT(p, MA_OWNED); 1603 prop = sigprop(sig); 1604 1605 /* 1606 * Find a thread to deliver the signal to. 1607 */ 1608 td = sigtd(p, sig, prop); 1609 1610 tdsignal(td, sig, SIGTARGET_P); 1611 } 1612 1613 /* 1614 * MPSAFE 1615 */ 1616 void 1617 tdsignal(struct thread *td, int sig, sigtarget_t target) 1618 { 1619 sigset_t saved; 1620 struct proc *p = td->td_proc; 1621 1622 if (p->p_flag & P_SA) 1623 saved = p->p_siglist; 1624 do_tdsignal(td, sig, target); 1625 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) { 1626 if (SIGSETEQ(saved, p->p_siglist)) 1627 return; 1628 else { 1629 /* pending set changed */ 1630 p->p_flag |= P_SIGEVENT; 1631 wakeup(&p->p_siglist); 1632 } 1633 } 1634 } 1635 1636 static void 1637 do_tdsignal(struct thread *td, int sig, sigtarget_t target) 1638 { 1639 struct proc *p; 1640 register sig_t action; 1641 sigset_t *siglist; 1642 struct thread *td0; 1643 register int prop; 1644 struct sigacts *ps; 1645 1646 KASSERT(_SIG_VALID(sig), 1647 ("tdsignal(): invalid signal %d\n", sig)); 1648 1649 p = td->td_proc; 1650 ps = p->p_sigacts; 1651 1652 PROC_LOCK_ASSERT(p, MA_OWNED); 1653 KNOTE(&p->p_klist, NOTE_SIGNAL | sig); 1654 1655 prop = sigprop(sig); 1656 1657 /* 1658 * If the signal is blocked and not destined for this thread, then 1659 * assign it to the process so that we can find it later in the first 1660 * thread that unblocks it. Otherwise, assign it to this thread now. 1661 */ 1662 siglist = (target != SIGTARGET_TD && SIGISMEMBER(td->td_sigmask, sig)) ? 1663 &p->p_siglist : &td->td_siglist; 1664 1665 /* 1666 * If proc is traced, always give parent a chance; 1667 * if signal event is tracked by procfs, give *that* 1668 * a chance, as well. 1669 */ 1670 if ((p->p_flag & P_TRACED) || (p->p_stops & S_SIG)) { 1671 action = SIG_DFL; 1672 } else { 1673 /* 1674 * If the signal is being ignored, 1675 * then we forget about it immediately. 1676 * (Note: we don't set SIGCONT in ps_sigignore, 1677 * and if it is set to SIG_IGN, 1678 * action will be SIG_DFL here.) 1679 */ 1680 mtx_lock(&ps->ps_mtx); 1681 if (SIGISMEMBER(ps->ps_sigignore, sig) || 1682 (p->p_flag & P_WEXIT)) { 1683 mtx_unlock(&ps->ps_mtx); 1684 return; 1685 } 1686 if (SIGISMEMBER(td->td_sigmask, sig)) 1687 action = SIG_HOLD; 1688 else if (SIGISMEMBER(ps->ps_sigcatch, sig)) 1689 action = SIG_CATCH; 1690 else 1691 action = SIG_DFL; 1692 mtx_unlock(&ps->ps_mtx); 1693 } 1694 1695 if (prop & SA_CONT) { 1696 SIG_STOPSIGMASK(p->p_siglist); 1697 /* 1698 * XXX Should investigate leaving STOP and CONT sigs only in 1699 * the proc's siglist. 1700 */ 1701 FOREACH_THREAD_IN_PROC(p, td0) 1702 SIG_STOPSIGMASK(td0->td_siglist); 1703 } 1704 1705 if (prop & SA_STOP) { 1706 /* 1707 * If sending a tty stop signal to a member of an orphaned 1708 * process group, discard the signal here if the action 1709 * is default; don't stop the process below if sleeping, 1710 * and don't clear any pending SIGCONT. 1711 */ 1712 if ((prop & SA_TTYSTOP) && 1713 (p->p_pgrp->pg_jobc == 0) && 1714 (action == SIG_DFL)) 1715 return; 1716 SIG_CONTSIGMASK(p->p_siglist); 1717 FOREACH_THREAD_IN_PROC(p, td0) 1718 SIG_CONTSIGMASK(td0->td_siglist); 1719 p->p_flag &= ~P_CONTINUED; 1720 } 1721 SIGADDSET(*siglist, sig); 1722 signotify(td); /* uses schedlock */ 1723 /* 1724 * Defer further processing for signals which are held, 1725 * except that stopped processes must be continued by SIGCONT. 1726 */ 1727 if (action == SIG_HOLD && 1728 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG))) 1729 return; 1730 /* 1731 * Some signals have a process-wide effect and a per-thread 1732 * component. Most processing occurs when the process next 1733 * tries to cross the user boundary, however there are some 1734 * times when processing needs to be done immediatly, such as 1735 * waking up threads so that they can cross the user boundary. 1736 * We try do the per-process part here. 1737 */ 1738 if (P_SHOULDSTOP(p)) { 1739 /* 1740 * The process is in stopped mode. All the threads should be 1741 * either winding down or already on the suspended queue. 1742 */ 1743 if (p->p_flag & P_TRACED) { 1744 /* 1745 * The traced process is already stopped, 1746 * so no further action is necessary. 1747 * No signal can restart us. 1748 */ 1749 goto out; 1750 } 1751 1752 if (sig == SIGKILL) { 1753 /* 1754 * SIGKILL sets process running. 1755 * It will die elsewhere. 1756 * All threads must be restarted. 1757 */ 1758 p->p_flag &= ~P_STOPPED; 1759 goto runfast; 1760 } 1761 1762 if (prop & SA_CONT) { 1763 /* 1764 * If SIGCONT is default (or ignored), we continue the 1765 * process but don't leave the signal in siglist as 1766 * it has no further action. If SIGCONT is held, we 1767 * continue the process and leave the signal in 1768 * siglist. If the process catches SIGCONT, let it 1769 * handle the signal itself. If it isn't waiting on 1770 * an event, it goes back to run state. 1771 * Otherwise, process goes back to sleep state. 1772 */ 1773 p->p_flag &= ~P_STOPPED_SIG; 1774 p->p_flag |= P_CONTINUED; 1775 if (action == SIG_DFL) { 1776 SIGDELSET(*siglist, sig); 1777 } else if (action == SIG_CATCH) { 1778 /* 1779 * The process wants to catch it so it needs 1780 * to run at least one thread, but which one? 1781 * It would seem that the answer would be to 1782 * run an upcall in the next KSE to run, and 1783 * deliver the signal that way. In a NON KSE 1784 * process, we need to make sure that the 1785 * single thread is runnable asap. 1786 * XXXKSE for now however, make them all run. 1787 */ 1788 goto runfast; 1789 } 1790 /* 1791 * The signal is not ignored or caught. 1792 */ 1793 mtx_lock_spin(&sched_lock); 1794 thread_unsuspend(p); 1795 mtx_unlock_spin(&sched_lock); 1796 goto out; 1797 } 1798 1799 if (prop & SA_STOP) { 1800 /* 1801 * Already stopped, don't need to stop again 1802 * (If we did the shell could get confused). 1803 * Just make sure the signal STOP bit set. 1804 */ 1805 p->p_flag |= P_STOPPED_SIG; 1806 SIGDELSET(*siglist, sig); 1807 goto out; 1808 } 1809 1810 /* 1811 * All other kinds of signals: 1812 * If a thread is sleeping interruptibly, simulate a 1813 * wakeup so that when it is continued it will be made 1814 * runnable and can look at the signal. However, don't make 1815 * the PROCESS runnable, leave it stopped. 1816 * It may run a bit until it hits a thread_suspend_check(). 1817 */ 1818 mtx_lock_spin(&sched_lock); 1819 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR)) { 1820 if (td->td_flags & TDF_CVWAITQ) 1821 cv_abort(td); 1822 else 1823 abortsleep(td); 1824 } 1825 mtx_unlock_spin(&sched_lock); 1826 goto out; 1827 /* 1828 * XXXKSE What about threads that are waiting on mutexes? 1829 * Shouldn't they abort too? 1830 * No, hopefully mutexes are short lived.. They'll 1831 * eventually hit thread_suspend_check(). 1832 */ 1833 } else if (p->p_state == PRS_NORMAL) { 1834 if ((p->p_flag & P_TRACED) || (action != SIG_DFL) || 1835 !(prop & SA_STOP)) { 1836 mtx_lock_spin(&sched_lock); 1837 tdsigwakeup(td, sig, action); 1838 mtx_unlock_spin(&sched_lock); 1839 goto out; 1840 } 1841 if (prop & SA_STOP) { 1842 if (p->p_flag & P_PPWAIT) 1843 goto out; 1844 p->p_flag |= P_STOPPED_SIG; 1845 p->p_xstat = sig; 1846 mtx_lock_spin(&sched_lock); 1847 FOREACH_THREAD_IN_PROC(p, td0) { 1848 if (TD_IS_SLEEPING(td0) && 1849 (td0->td_flags & TDF_SINTR) && 1850 !TD_IS_SUSPENDED(td0)) { 1851 thread_suspend_one(td0); 1852 } else if (td != td0) { 1853 td0->td_flags |= TDF_ASTPENDING; 1854 } 1855 } 1856 thread_stopped(p); 1857 if (p->p_numthreads == p->p_suspcount) { 1858 SIGDELSET(p->p_siglist, p->p_xstat); 1859 FOREACH_THREAD_IN_PROC(p, td0) 1860 SIGDELSET(td0->td_siglist, p->p_xstat); 1861 } 1862 mtx_unlock_spin(&sched_lock); 1863 goto out; 1864 } 1865 else 1866 goto runfast; 1867 /* NOTREACHED */ 1868 } else { 1869 /* Not in "NORMAL" state. discard the signal. */ 1870 SIGDELSET(*siglist, sig); 1871 goto out; 1872 } 1873 1874 /* 1875 * The process is not stopped so we need to apply the signal to all the 1876 * running threads. 1877 */ 1878 1879 runfast: 1880 mtx_lock_spin(&sched_lock); 1881 tdsigwakeup(td, sig, action); 1882 thread_unsuspend(p); 1883 mtx_unlock_spin(&sched_lock); 1884 out: 1885 /* If we jump here, sched_lock should not be owned. */ 1886 mtx_assert(&sched_lock, MA_NOTOWNED); 1887 } 1888 1889 /* 1890 * The force of a signal has been directed against a single 1891 * thread. We need to see what we can do about knocking it 1892 * out of any sleep it may be in etc. 1893 */ 1894 static void 1895 tdsigwakeup(struct thread *td, int sig, sig_t action) 1896 { 1897 struct proc *p = td->td_proc; 1898 register int prop; 1899 1900 PROC_LOCK_ASSERT(p, MA_OWNED); 1901 mtx_assert(&sched_lock, MA_OWNED); 1902 prop = sigprop(sig); 1903 /* 1904 * Bring the priority of a thread up if we want it to get 1905 * killed in this lifetime. 1906 */ 1907 if ((action == SIG_DFL) && (prop & SA_KILL)) { 1908 if (td->td_priority > PUSER) { 1909 td->td_priority = PUSER; 1910 } 1911 } 1912 if (TD_IS_SLEEPING(td)) { 1913 /* 1914 * If thread is sleeping uninterruptibly 1915 * we can't interrupt the sleep... the signal will 1916 * be noticed when the process returns through 1917 * trap() or syscall(). 1918 */ 1919 if ((td->td_flags & TDF_SINTR) == 0) { 1920 return; 1921 } 1922 /* 1923 * Process is sleeping and traced. Make it runnable 1924 * so it can discover the signal in issignal() and stop 1925 * for its parent. 1926 */ 1927 if (p->p_flag & P_TRACED) { 1928 p->p_flag &= ~P_STOPPED_TRACE; 1929 } else { 1930 1931 /* 1932 * If SIGCONT is default (or ignored) and process is 1933 * asleep, we are finished; the process should not 1934 * be awakened. 1935 */ 1936 if ((prop & SA_CONT) && action == SIG_DFL) { 1937 SIGDELSET(p->p_siglist, sig); 1938 /* 1939 * It may be on either list in this state. 1940 * Remove from both for now. 1941 */ 1942 SIGDELSET(td->td_siglist, sig); 1943 return; 1944 } 1945 1946 /* 1947 * Raise priority to at least PUSER. 1948 */ 1949 if (td->td_priority > PUSER) { 1950 td->td_priority = PUSER; 1951 } 1952 } 1953 if (td->td_flags & TDF_CVWAITQ) 1954 cv_abort(td); 1955 else 1956 abortsleep(td); 1957 } 1958 #ifdef SMP 1959 else { 1960 /* 1961 * Other states do nothing with the signal immediatly, 1962 * other than kicking ourselves if we are running. 1963 * It will either never be noticed, or noticed very soon. 1964 */ 1965 if (TD_IS_RUNNING(td) && td != curthread) { 1966 forward_signal(td); 1967 } 1968 } 1969 #endif 1970 } 1971 1972 /* 1973 * If the current process has received a signal (should be caught or cause 1974 * termination, should interrupt current syscall), return the signal number. 1975 * Stop signals with default action are processed immediately, then cleared; 1976 * they aren't returned. This is checked after each entry to the system for 1977 * a syscall or trap (though this can usually be done without calling issignal 1978 * by checking the pending signal masks in cursig.) The normal call 1979 * sequence is 1980 * 1981 * while (sig = cursig(curthread)) 1982 * postsig(sig); 1983 */ 1984 static int 1985 issignal(td) 1986 struct thread *td; 1987 { 1988 struct proc *p; 1989 struct sigacts *ps; 1990 sigset_t sigpending; 1991 int sig, prop; 1992 struct thread *td0; 1993 1994 p = td->td_proc; 1995 ps = p->p_sigacts; 1996 mtx_assert(&ps->ps_mtx, MA_OWNED); 1997 PROC_LOCK_ASSERT(p, MA_OWNED); 1998 for (;;) { 1999 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG); 2000 2001 sigpending = td->td_siglist; 2002 SIGSETNAND(sigpending, td->td_sigmask); 2003 2004 if (p->p_flag & P_PPWAIT) 2005 SIG_STOPSIGMASK(sigpending); 2006 if (SIGISEMPTY(sigpending)) /* no signal to send */ 2007 return (0); 2008 sig = sig_ffs(&sigpending); 2009 2010 _STOPEVENT(p, S_SIG, sig); 2011 2012 /* 2013 * We should see pending but ignored signals 2014 * only if P_TRACED was on when they were posted. 2015 */ 2016 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) { 2017 SIGDELSET(td->td_siglist, sig); 2018 continue; 2019 } 2020 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) { 2021 /* 2022 * If traced, always stop. 2023 */ 2024 mtx_unlock(&ps->ps_mtx); 2025 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2026 &p->p_mtx.mtx_object, "Stopping for traced signal"); 2027 p->p_xstat = sig; 2028 PROC_LOCK(p->p_pptr); 2029 psignal(p->p_pptr, SIGCHLD); 2030 PROC_UNLOCK(p->p_pptr); 2031 mtx_lock_spin(&sched_lock); 2032 stop(p); /* uses schedlock too eventually */ 2033 thread_suspend_one(td); 2034 PROC_UNLOCK(p); 2035 DROP_GIANT(); 2036 p->p_stats->p_ru.ru_nivcsw++; 2037 mi_switch(); 2038 mtx_unlock_spin(&sched_lock); 2039 PICKUP_GIANT(); 2040 PROC_LOCK(p); 2041 mtx_lock(&ps->ps_mtx); 2042 2043 /* 2044 * If parent wants us to take the signal, 2045 * then it will leave it in p->p_xstat; 2046 * otherwise we just look for signals again. 2047 */ 2048 SIGDELSET(td->td_siglist, sig); /* clear old signal */ 2049 sig = p->p_xstat; 2050 if (sig == 0) 2051 continue; 2052 2053 /* 2054 * If the traced bit got turned off, go back up 2055 * to the top to rescan signals. This ensures 2056 * that p_sig* and p_sigact are consistent. 2057 */ 2058 if ((p->p_flag & P_TRACED) == 0) 2059 continue; 2060 2061 /* 2062 * Put the new signal into td_siglist. If the 2063 * signal is being masked, look for other signals. 2064 */ 2065 SIGADDSET(td->td_siglist, sig); 2066 if (SIGISMEMBER(td->td_sigmask, sig)) 2067 continue; 2068 signotify(td); 2069 } 2070 2071 prop = sigprop(sig); 2072 2073 /* 2074 * Decide whether the signal should be returned. 2075 * Return the signal's number, or fall through 2076 * to clear it from the pending mask. 2077 */ 2078 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) { 2079 2080 case (intptr_t)SIG_DFL: 2081 /* 2082 * Don't take default actions on system processes. 2083 */ 2084 if (p->p_pid <= 1) { 2085 #ifdef DIAGNOSTIC 2086 /* 2087 * Are you sure you want to ignore SIGSEGV 2088 * in init? XXX 2089 */ 2090 printf("Process (pid %lu) got signal %d\n", 2091 (u_long)p->p_pid, sig); 2092 #endif 2093 break; /* == ignore */ 2094 } 2095 /* 2096 * If there is a pending stop signal to process 2097 * with default action, stop here, 2098 * then clear the signal. However, 2099 * if process is member of an orphaned 2100 * process group, ignore tty stop signals. 2101 */ 2102 if (prop & SA_STOP) { 2103 if (p->p_flag & P_TRACED || 2104 (p->p_pgrp->pg_jobc == 0 && 2105 prop & SA_TTYSTOP)) 2106 break; /* == ignore */ 2107 mtx_unlock(&ps->ps_mtx); 2108 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, 2109 &p->p_mtx.mtx_object, "Catching SIGSTOP"); 2110 p->p_flag |= P_STOPPED_SIG; 2111 p->p_xstat = sig; 2112 mtx_lock_spin(&sched_lock); 2113 FOREACH_THREAD_IN_PROC(p, td0) { 2114 if (TD_IS_SLEEPING(td0) && 2115 (td0->td_flags & TDF_SINTR) && 2116 !TD_IS_SUSPENDED(td0)) { 2117 thread_suspend_one(td0); 2118 } else if (td != td0) { 2119 td0->td_flags |= TDF_ASTPENDING; 2120 } 2121 } 2122 thread_stopped(p); 2123 thread_suspend_one(td); 2124 PROC_UNLOCK(p); 2125 DROP_GIANT(); 2126 p->p_stats->p_ru.ru_nivcsw++; 2127 mi_switch(); 2128 mtx_unlock_spin(&sched_lock); 2129 PICKUP_GIANT(); 2130 PROC_LOCK(p); 2131 mtx_lock(&ps->ps_mtx); 2132 break; 2133 } else if (prop & SA_IGNORE) { 2134 /* 2135 * Except for SIGCONT, shouldn't get here. 2136 * Default action is to ignore; drop it. 2137 */ 2138 break; /* == ignore */ 2139 } else 2140 return (sig); 2141 /*NOTREACHED*/ 2142 2143 case (intptr_t)SIG_IGN: 2144 /* 2145 * Masking above should prevent us ever trying 2146 * to take action on an ignored signal other 2147 * than SIGCONT, unless process is traced. 2148 */ 2149 if ((prop & SA_CONT) == 0 && 2150 (p->p_flag & P_TRACED) == 0) 2151 printf("issignal\n"); 2152 break; /* == ignore */ 2153 2154 default: 2155 /* 2156 * This signal has an action, let 2157 * postsig() process it. 2158 */ 2159 return (sig); 2160 } 2161 SIGDELSET(td->td_siglist, sig); /* take the signal! */ 2162 } 2163 /* NOTREACHED */ 2164 } 2165 2166 /* 2167 * Put the argument process into the stopped state and notify the parent 2168 * via wakeup. Signals are handled elsewhere. The process must not be 2169 * on the run queue. Must be called with the proc p locked and the scheduler 2170 * lock held. 2171 */ 2172 static void 2173 stop(struct proc *p) 2174 { 2175 2176 PROC_LOCK_ASSERT(p, MA_OWNED); 2177 p->p_flag |= P_STOPPED_SIG; 2178 p->p_flag &= ~P_WAITED; 2179 wakeup(p->p_pptr); 2180 } 2181 2182 /* 2183 * MPSAFE 2184 */ 2185 void 2186 thread_stopped(struct proc *p) 2187 { 2188 struct proc *p1 = curthread->td_proc; 2189 struct sigacts *ps; 2190 int n; 2191 2192 PROC_LOCK_ASSERT(p, MA_OWNED); 2193 mtx_assert(&sched_lock, MA_OWNED); 2194 n = p->p_suspcount; 2195 if (p == p1) 2196 n++; 2197 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) { 2198 mtx_unlock_spin(&sched_lock); 2199 stop(p); 2200 PROC_LOCK(p->p_pptr); 2201 ps = p->p_pptr->p_sigacts; 2202 mtx_lock(&ps->ps_mtx); 2203 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) { 2204 mtx_unlock(&ps->ps_mtx); 2205 psignal(p->p_pptr, SIGCHLD); 2206 } else 2207 mtx_unlock(&ps->ps_mtx); 2208 PROC_UNLOCK(p->p_pptr); 2209 mtx_lock_spin(&sched_lock); 2210 } 2211 } 2212 2213 /* 2214 * Take the action for the specified signal 2215 * from the current set of pending signals. 2216 */ 2217 void 2218 postsig(sig) 2219 register int sig; 2220 { 2221 struct thread *td = curthread; 2222 register struct proc *p = td->td_proc; 2223 struct sigacts *ps; 2224 sig_t action; 2225 sigset_t returnmask; 2226 int code; 2227 2228 KASSERT(sig != 0, ("postsig")); 2229 2230 PROC_LOCK_ASSERT(p, MA_OWNED); 2231 ps = p->p_sigacts; 2232 mtx_assert(&ps->ps_mtx, MA_OWNED); 2233 SIGDELSET(td->td_siglist, sig); 2234 action = ps->ps_sigact[_SIG_IDX(sig)]; 2235 #ifdef KTRACE 2236 if (KTRPOINT(td, KTR_PSIG)) 2237 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ? 2238 &td->td_oldsigmask : &td->td_sigmask, 0); 2239 #endif 2240 _STOPEVENT(p, S_SIG, sig); 2241 2242 if (action == SIG_DFL) { 2243 /* 2244 * Default action, where the default is to kill 2245 * the process. (Other cases were ignored above.) 2246 */ 2247 mtx_unlock(&ps->ps_mtx); 2248 sigexit(td, sig); 2249 /* NOTREACHED */ 2250 } else { 2251 /* 2252 * If we get here, the signal must be caught. 2253 */ 2254 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig), 2255 ("postsig action")); 2256 /* 2257 * Set the new mask value and also defer further 2258 * occurrences of this signal. 2259 * 2260 * Special case: user has done a sigsuspend. Here the 2261 * current mask is not of interest, but rather the 2262 * mask from before the sigsuspend is what we want 2263 * restored after the signal processing is completed. 2264 */ 2265 if (td->td_pflags & TDP_OLDMASK) { 2266 returnmask = td->td_oldsigmask; 2267 td->td_pflags &= ~TDP_OLDMASK; 2268 } else 2269 returnmask = td->td_sigmask; 2270 2271 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 2272 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 2273 SIGADDSET(td->td_sigmask, sig); 2274 2275 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 2276 /* 2277 * See kern_sigaction() for origin of this code. 2278 */ 2279 SIGDELSET(ps->ps_sigcatch, sig); 2280 if (sig != SIGCONT && 2281 sigprop(sig) & SA_IGNORE) 2282 SIGADDSET(ps->ps_sigignore, sig); 2283 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 2284 } 2285 p->p_stats->p_ru.ru_nsignals++; 2286 if (p->p_sig != sig) { 2287 code = 0; 2288 } else { 2289 code = p->p_code; 2290 p->p_code = 0; 2291 p->p_sig = 0; 2292 } 2293 if (td->td_flags & TDF_SA) 2294 thread_signal_add(curthread, sig); 2295 else 2296 (*p->p_sysent->sv_sendsig)(action, sig, 2297 &returnmask, code); 2298 } 2299 } 2300 2301 /* 2302 * Kill the current process for stated reason. 2303 */ 2304 void 2305 killproc(p, why) 2306 struct proc *p; 2307 char *why; 2308 { 2309 2310 PROC_LOCK_ASSERT(p, MA_OWNED); 2311 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", 2312 p, p->p_pid, p->p_comm); 2313 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm, 2314 p->p_ucred ? p->p_ucred->cr_uid : -1, why); 2315 psignal(p, SIGKILL); 2316 } 2317 2318 /* 2319 * Force the current process to exit with the specified signal, dumping core 2320 * if appropriate. We bypass the normal tests for masked and caught signals, 2321 * allowing unrecoverable failures to terminate the process without changing 2322 * signal state. Mark the accounting record with the signal termination. 2323 * If dumping core, save the signal number for the debugger. Calls exit and 2324 * does not return. 2325 * 2326 * MPSAFE 2327 */ 2328 void 2329 sigexit(td, sig) 2330 struct thread *td; 2331 int sig; 2332 { 2333 struct proc *p = td->td_proc; 2334 2335 PROC_LOCK_ASSERT(p, MA_OWNED); 2336 p->p_acflag |= AXSIG; 2337 if (sigprop(sig) & SA_CORE) { 2338 p->p_sig = sig; 2339 /* 2340 * Log signals which would cause core dumps 2341 * (Log as LOG_INFO to appease those who don't want 2342 * these messages.) 2343 * XXX : Todo, as well as euid, write out ruid too 2344 */ 2345 PROC_UNLOCK(p); 2346 if (!mtx_owned(&Giant)) 2347 mtx_lock(&Giant); 2348 if (coredump(td) == 0) 2349 sig |= WCOREFLAG; 2350 if (kern_logsigexit) 2351 log(LOG_INFO, 2352 "pid %d (%s), uid %d: exited on signal %d%s\n", 2353 p->p_pid, p->p_comm, 2354 td->td_ucred ? td->td_ucred->cr_uid : -1, 2355 sig &~ WCOREFLAG, 2356 sig & WCOREFLAG ? " (core dumped)" : ""); 2357 } else { 2358 PROC_UNLOCK(p); 2359 if (!mtx_owned(&Giant)) 2360 mtx_lock(&Giant); 2361 } 2362 exit1(td, W_EXITCODE(0, sig)); 2363 /* NOTREACHED */ 2364 } 2365 2366 static char corefilename[MAXPATHLEN+1] = {"%N.core"}; 2367 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename, 2368 sizeof(corefilename), "process corefile name format string"); 2369 2370 /* 2371 * expand_name(name, uid, pid) 2372 * Expand the name described in corefilename, using name, uid, and pid. 2373 * corefilename is a printf-like string, with three format specifiers: 2374 * %N name of process ("name") 2375 * %P process id (pid) 2376 * %U user id (uid) 2377 * For example, "%N.core" is the default; they can be disabled completely 2378 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P". 2379 * This is controlled by the sysctl variable kern.corefile (see above). 2380 */ 2381 2382 static char * 2383 expand_name(name, uid, pid) 2384 const char *name; 2385 uid_t uid; 2386 pid_t pid; 2387 { 2388 const char *format, *appendstr; 2389 char *temp; 2390 char buf[11]; /* Buffer for pid/uid -- max 4B */ 2391 size_t i, l, n; 2392 2393 format = corefilename; 2394 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO); 2395 if (temp == NULL) 2396 return (NULL); 2397 for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) { 2398 switch (format[i]) { 2399 case '%': /* Format character */ 2400 i++; 2401 switch (format[i]) { 2402 case '%': 2403 appendstr = "%"; 2404 break; 2405 case 'N': /* process name */ 2406 appendstr = name; 2407 break; 2408 case 'P': /* process id */ 2409 sprintf(buf, "%u", pid); 2410 appendstr = buf; 2411 break; 2412 case 'U': /* user id */ 2413 sprintf(buf, "%u", uid); 2414 appendstr = buf; 2415 break; 2416 default: 2417 appendstr = ""; 2418 log(LOG_ERR, 2419 "Unknown format character %c in `%s'\n", 2420 format[i], format); 2421 } 2422 l = strlen(appendstr); 2423 if ((n + l) >= MAXPATHLEN) 2424 goto toolong; 2425 memcpy(temp + n, appendstr, l); 2426 n += l; 2427 break; 2428 default: 2429 temp[n++] = format[i]; 2430 } 2431 } 2432 if (format[i] != '\0') 2433 goto toolong; 2434 return (temp); 2435 toolong: 2436 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too long\n", 2437 (long)pid, name, (u_long)uid); 2438 free(temp, M_TEMP); 2439 return (NULL); 2440 } 2441 2442 /* 2443 * Dump a process' core. The main routine does some 2444 * policy checking, and creates the name of the coredump; 2445 * then it passes on a vnode and a size limit to the process-specific 2446 * coredump routine if there is one; if there _is not_ one, it returns 2447 * ENOSYS; otherwise it returns the error from the process-specific routine. 2448 */ 2449 2450 static int 2451 coredump(struct thread *td) 2452 { 2453 struct proc *p = td->td_proc; 2454 register struct vnode *vp; 2455 register struct ucred *cred = td->td_ucred; 2456 struct flock lf; 2457 struct nameidata nd; 2458 struct vattr vattr; 2459 int error, error1, flags; 2460 struct mount *mp; 2461 char *name; /* name of corefile */ 2462 off_t limit; 2463 2464 PROC_LOCK(p); 2465 _STOPEVENT(p, S_CORE, 0); 2466 2467 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) { 2468 PROC_UNLOCK(p); 2469 return (EFAULT); 2470 } 2471 2472 /* 2473 * Note that the bulk of limit checking is done after 2474 * the corefile is created. The exception is if the limit 2475 * for corefiles is 0, in which case we don't bother 2476 * creating the corefile at all. This layout means that 2477 * a corefile is truncated instead of not being created, 2478 * if it is larger than the limit. 2479 */ 2480 limit = p->p_rlimit[RLIMIT_CORE].rlim_cur; 2481 if (limit == 0) { 2482 PROC_UNLOCK(p); 2483 return 0; 2484 } 2485 PROC_UNLOCK(p); 2486 2487 restart: 2488 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid); 2489 if (name == NULL) 2490 return (EINVAL); 2491 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); /* XXXKSE */ 2492 flags = O_CREAT | FWRITE | O_NOFOLLOW; 2493 error = vn_open(&nd, &flags, S_IRUSR | S_IWUSR); 2494 free(name, M_TEMP); 2495 if (error) 2496 return (error); 2497 NDFREE(&nd, NDF_ONLY_PNBUF); 2498 vp = nd.ni_vp; 2499 2500 /* Don't dump to non-regular files or files with links. */ 2501 if (vp->v_type != VREG || 2502 VOP_GETATTR(vp, &vattr, cred, td) || vattr.va_nlink != 1) { 2503 VOP_UNLOCK(vp, 0, td); 2504 error = EFAULT; 2505 goto out2; 2506 } 2507 2508 VOP_UNLOCK(vp, 0, td); 2509 lf.l_whence = SEEK_SET; 2510 lf.l_start = 0; 2511 lf.l_len = 0; 2512 lf.l_type = F_WRLCK; 2513 error = VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK); 2514 if (error) 2515 goto out2; 2516 2517 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 2518 lf.l_type = F_UNLCK; 2519 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2520 if ((error = vn_close(vp, FWRITE, cred, td)) != 0) 2521 return (error); 2522 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0) 2523 return (error); 2524 goto restart; 2525 } 2526 2527 VATTR_NULL(&vattr); 2528 vattr.va_size = 0; 2529 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 2530 VOP_LEASE(vp, td, cred, LEASE_WRITE); 2531 VOP_SETATTR(vp, &vattr, cred, td); 2532 VOP_UNLOCK(vp, 0, td); 2533 PROC_LOCK(p); 2534 p->p_acflag |= ACORE; 2535 PROC_UNLOCK(p); 2536 2537 error = p->p_sysent->sv_coredump ? 2538 p->p_sysent->sv_coredump(td, vp, limit) : 2539 ENOSYS; 2540 2541 lf.l_type = F_UNLCK; 2542 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2543 vn_finished_write(mp); 2544 out2: 2545 error1 = vn_close(vp, FWRITE, cred, td); 2546 if (error == 0) 2547 error = error1; 2548 return (error); 2549 } 2550 2551 /* 2552 * Nonexistent system call-- signal process (may want to handle it). 2553 * Flag error in case process won't see signal immediately (blocked or ignored). 2554 */ 2555 #ifndef _SYS_SYSPROTO_H_ 2556 struct nosys_args { 2557 int dummy; 2558 }; 2559 #endif 2560 /* 2561 * MPSAFE 2562 */ 2563 /* ARGSUSED */ 2564 int 2565 nosys(td, args) 2566 struct thread *td; 2567 struct nosys_args *args; 2568 { 2569 struct proc *p = td->td_proc; 2570 2571 PROC_LOCK(p); 2572 psignal(p, SIGSYS); 2573 PROC_UNLOCK(p); 2574 return (ENOSYS); 2575 } 2576 2577 /* 2578 * Send a SIGIO or SIGURG signal to a process or process group using 2579 * stored credentials rather than those of the current process. 2580 */ 2581 void 2582 pgsigio(sigiop, sig, checkctty) 2583 struct sigio **sigiop; 2584 int sig, checkctty; 2585 { 2586 struct sigio *sigio; 2587 2588 SIGIO_LOCK(); 2589 sigio = *sigiop; 2590 if (sigio == NULL) { 2591 SIGIO_UNLOCK(); 2592 return; 2593 } 2594 if (sigio->sio_pgid > 0) { 2595 PROC_LOCK(sigio->sio_proc); 2596 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred)) 2597 psignal(sigio->sio_proc, sig); 2598 PROC_UNLOCK(sigio->sio_proc); 2599 } else if (sigio->sio_pgid < 0) { 2600 struct proc *p; 2601 2602 PGRP_LOCK(sigio->sio_pgrp); 2603 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) { 2604 PROC_LOCK(p); 2605 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) && 2606 (checkctty == 0 || (p->p_flag & P_CONTROLT))) 2607 psignal(p, sig); 2608 PROC_UNLOCK(p); 2609 } 2610 PGRP_UNLOCK(sigio->sio_pgrp); 2611 } 2612 SIGIO_UNLOCK(); 2613 } 2614 2615 static int 2616 filt_sigattach(struct knote *kn) 2617 { 2618 struct proc *p = curproc; 2619 2620 kn->kn_ptr.p_proc = p; 2621 kn->kn_flags |= EV_CLEAR; /* automatically set */ 2622 2623 PROC_LOCK(p); 2624 SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext); 2625 PROC_UNLOCK(p); 2626 2627 return (0); 2628 } 2629 2630 static void 2631 filt_sigdetach(struct knote *kn) 2632 { 2633 struct proc *p = kn->kn_ptr.p_proc; 2634 2635 PROC_LOCK(p); 2636 SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext); 2637 PROC_UNLOCK(p); 2638 } 2639 2640 /* 2641 * signal knotes are shared with proc knotes, so we apply a mask to 2642 * the hint in order to differentiate them from process hints. This 2643 * could be avoided by using a signal-specific knote list, but probably 2644 * isn't worth the trouble. 2645 */ 2646 static int 2647 filt_signal(struct knote *kn, long hint) 2648 { 2649 2650 if (hint & NOTE_SIGNAL) { 2651 hint &= ~NOTE_SIGNAL; 2652 2653 if (kn->kn_id == hint) 2654 kn->kn_data++; 2655 } 2656 return (kn->kn_data != 0); 2657 } 2658 2659 struct sigacts * 2660 sigacts_alloc(void) 2661 { 2662 struct sigacts *ps; 2663 2664 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO); 2665 ps->ps_refcnt = 1; 2666 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF); 2667 return (ps); 2668 } 2669 2670 void 2671 sigacts_free(struct sigacts *ps) 2672 { 2673 2674 mtx_lock(&ps->ps_mtx); 2675 ps->ps_refcnt--; 2676 if (ps->ps_refcnt == 0) { 2677 mtx_destroy(&ps->ps_mtx); 2678 free(ps, M_SUBPROC); 2679 } else 2680 mtx_unlock(&ps->ps_mtx); 2681 } 2682 2683 struct sigacts * 2684 sigacts_hold(struct sigacts *ps) 2685 { 2686 mtx_lock(&ps->ps_mtx); 2687 ps->ps_refcnt++; 2688 mtx_unlock(&ps->ps_mtx); 2689 return (ps); 2690 } 2691 2692 void 2693 sigacts_copy(struct sigacts *dest, struct sigacts *src) 2694 { 2695 2696 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest")); 2697 mtx_lock(&src->ps_mtx); 2698 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt)); 2699 mtx_unlock(&src->ps_mtx); 2700 } 2701 2702 int 2703 sigacts_shared(struct sigacts *ps) 2704 { 2705 int shared; 2706 2707 mtx_lock(&ps->ps_mtx); 2708 shared = ps->ps_refcnt > 1; 2709 mtx_unlock(&ps->ps_mtx); 2710 return (shared); 2711 } 2712