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 * $FreeBSD$ 40 */ 41 42 #include "opt_compat.h" 43 #include "opt_ktrace.h" 44 45 #include <sys/param.h> 46 #include <sys/kernel.h> 47 #include <sys/sysproto.h> 48 #include <sys/systm.h> 49 #include <sys/signalvar.h> 50 #include <sys/namei.h> 51 #include <sys/vnode.h> 52 #include <sys/event.h> 53 #include <sys/proc.h> 54 #include <sys/pioctl.h> 55 #include <sys/acct.h> 56 #include <sys/fcntl.h> 57 #include <sys/condvar.h> 58 #include <sys/lock.h> 59 #include <sys/mutex.h> 60 #include <sys/wait.h> 61 #include <sys/ktr.h> 62 #include <sys/ktrace.h> 63 #include <sys/resourcevar.h> 64 #include <sys/smp.h> 65 #include <sys/stat.h> 66 #include <sys/sx.h> 67 #include <sys/syslog.h> 68 #include <sys/sysent.h> 69 #include <sys/sysctl.h> 70 #include <sys/malloc.h> 71 #include <sys/unistd.h> 72 73 #include <machine/cpu.h> 74 75 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */ 76 77 static int coredump __P((struct thread *)); 78 static int do_sigaction __P((struct proc *p, int sig, struct sigaction *act, 79 struct sigaction *oact, int old)); 80 static int do_sigprocmask __P((struct proc *p, int how, sigset_t *set, 81 sigset_t *oset, int old)); 82 static char *expand_name __P((const char *, uid_t, pid_t)); 83 static int killpg1 __P((struct proc *cp, int sig, int pgid, int all)); 84 static int sig_ffs __P((sigset_t *set)); 85 static int sigprop __P((int sig)); 86 static void stop __P((struct proc *)); 87 88 static int filt_sigattach(struct knote *kn); 89 static void filt_sigdetach(struct knote *kn); 90 static int filt_signal(struct knote *kn, long hint); 91 92 struct filterops sig_filtops = 93 { 0, filt_sigattach, filt_sigdetach, filt_signal }; 94 95 static int kern_logsigexit = 1; 96 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW, 97 &kern_logsigexit, 0, 98 "Log processes quitting on abnormal signals to syslog(3)"); 99 100 /* 101 * Policy -- Can ucred cr1 send SIGIO to process cr2? 102 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG 103 * in the right situations. 104 */ 105 #define CANSIGIO(cr1, cr2) \ 106 ((cr1)->cr_uid == 0 || \ 107 (cr1)->cr_ruid == (cr2)->cr_ruid || \ 108 (cr1)->cr_uid == (cr2)->cr_ruid || \ 109 (cr1)->cr_ruid == (cr2)->cr_uid || \ 110 (cr1)->cr_uid == (cr2)->cr_uid) 111 112 int sugid_coredump; 113 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW, 114 &sugid_coredump, 0, "Enable coredumping set user/group ID processes"); 115 116 static int do_coredump = 1; 117 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW, 118 &do_coredump, 0, "Enable/Disable coredumps"); 119 120 /* 121 * Signal properties and actions. 122 * The array below categorizes the signals and their default actions 123 * according to the following properties: 124 */ 125 #define SA_KILL 0x01 /* terminates process by default */ 126 #define SA_CORE 0x02 /* ditto and coredumps */ 127 #define SA_STOP 0x04 /* suspend process */ 128 #define SA_TTYSTOP 0x08 /* ditto, from tty */ 129 #define SA_IGNORE 0x10 /* ignore by default */ 130 #define SA_CONT 0x20 /* continue if suspended */ 131 #define SA_CANTMASK 0x40 /* non-maskable, catchable */ 132 133 static int sigproptbl[NSIG] = { 134 SA_KILL, /* SIGHUP */ 135 SA_KILL, /* SIGINT */ 136 SA_KILL|SA_CORE, /* SIGQUIT */ 137 SA_KILL|SA_CORE, /* SIGILL */ 138 SA_KILL|SA_CORE, /* SIGTRAP */ 139 SA_KILL|SA_CORE, /* SIGABRT */ 140 SA_KILL|SA_CORE, /* SIGEMT */ 141 SA_KILL|SA_CORE, /* SIGFPE */ 142 SA_KILL, /* SIGKILL */ 143 SA_KILL|SA_CORE, /* SIGBUS */ 144 SA_KILL|SA_CORE, /* SIGSEGV */ 145 SA_KILL|SA_CORE, /* SIGSYS */ 146 SA_KILL, /* SIGPIPE */ 147 SA_KILL, /* SIGALRM */ 148 SA_KILL, /* SIGTERM */ 149 SA_IGNORE, /* SIGURG */ 150 SA_STOP, /* SIGSTOP */ 151 SA_STOP|SA_TTYSTOP, /* SIGTSTP */ 152 SA_IGNORE|SA_CONT, /* SIGCONT */ 153 SA_IGNORE, /* SIGCHLD */ 154 SA_STOP|SA_TTYSTOP, /* SIGTTIN */ 155 SA_STOP|SA_TTYSTOP, /* SIGTTOU */ 156 SA_IGNORE, /* SIGIO */ 157 SA_KILL, /* SIGXCPU */ 158 SA_KILL, /* SIGXFSZ */ 159 SA_KILL, /* SIGVTALRM */ 160 SA_KILL, /* SIGPROF */ 161 SA_IGNORE, /* SIGWINCH */ 162 SA_IGNORE, /* SIGINFO */ 163 SA_KILL, /* SIGUSR1 */ 164 SA_KILL, /* SIGUSR2 */ 165 }; 166 167 /* 168 * Determine signal that should be delivered to process p, the current 169 * process, 0 if none. If there is a pending stop signal with default 170 * action, the process stops in issignal(). 171 * 172 * MP SAFE. 173 */ 174 int 175 CURSIG(struct proc *p) 176 { 177 sigset_t tmpset; 178 179 PROC_LOCK_ASSERT(p, MA_OWNED); 180 if (SIGISEMPTY(p->p_siglist)) 181 return (0); 182 tmpset = p->p_siglist; 183 SIGSETNAND(tmpset, p->p_sigmask); 184 if (SIGISEMPTY(tmpset) && (p->p_flag & P_TRACED) == 0) 185 return (0); 186 return (issignal(p)); 187 } 188 189 static __inline int 190 sigprop(int sig) 191 { 192 193 if (sig > 0 && sig < NSIG) 194 return (sigproptbl[_SIG_IDX(sig)]); 195 return (0); 196 } 197 198 static __inline int 199 sig_ffs(sigset_t *set) 200 { 201 int i; 202 203 for (i = 0; i < _SIG_WORDS; i++) 204 if (set->__bits[i]) 205 return (ffs(set->__bits[i]) + (i * 32)); 206 return (0); 207 } 208 209 /* 210 * do_sigaction 211 * sigaction 212 * osigaction 213 */ 214 static int 215 do_sigaction(p, sig, act, oact, old) 216 struct proc *p; 217 register int sig; 218 struct sigaction *act, *oact; 219 int old; 220 { 221 register struct sigacts *ps; 222 223 if (!_SIG_VALID(sig)) 224 return (EINVAL); 225 226 PROC_LOCK(p); 227 ps = p->p_sigacts; 228 if (oact) { 229 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)]; 230 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)]; 231 oact->sa_flags = 0; 232 if (SIGISMEMBER(ps->ps_sigonstack, sig)) 233 oact->sa_flags |= SA_ONSTACK; 234 if (!SIGISMEMBER(ps->ps_sigintr, sig)) 235 oact->sa_flags |= SA_RESTART; 236 if (SIGISMEMBER(ps->ps_sigreset, sig)) 237 oact->sa_flags |= SA_RESETHAND; 238 if (SIGISMEMBER(ps->ps_signodefer, sig)) 239 oact->sa_flags |= SA_NODEFER; 240 if (SIGISMEMBER(ps->ps_siginfo, sig)) 241 oact->sa_flags |= SA_SIGINFO; 242 if (sig == SIGCHLD && p->p_procsig->ps_flag & PS_NOCLDSTOP) 243 oact->sa_flags |= SA_NOCLDSTOP; 244 if (sig == SIGCHLD && p->p_procsig->ps_flag & PS_NOCLDWAIT) 245 oact->sa_flags |= SA_NOCLDWAIT; 246 } 247 if (act) { 248 if ((sig == SIGKILL || sig == SIGSTOP) && 249 act->sa_handler != SIG_DFL) { 250 PROC_UNLOCK(p); 251 return (EINVAL); 252 } 253 254 /* 255 * Change setting atomically. 256 */ 257 258 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask; 259 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]); 260 if (act->sa_flags & SA_SIGINFO) { 261 ps->ps_sigact[_SIG_IDX(sig)] = 262 (__sighandler_t *)act->sa_sigaction; 263 SIGADDSET(ps->ps_siginfo, sig); 264 } else { 265 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler; 266 SIGDELSET(ps->ps_siginfo, sig); 267 } 268 if (!(act->sa_flags & SA_RESTART)) 269 SIGADDSET(ps->ps_sigintr, sig); 270 else 271 SIGDELSET(ps->ps_sigintr, sig); 272 if (act->sa_flags & SA_ONSTACK) 273 SIGADDSET(ps->ps_sigonstack, sig); 274 else 275 SIGDELSET(ps->ps_sigonstack, sig); 276 if (act->sa_flags & SA_RESETHAND) 277 SIGADDSET(ps->ps_sigreset, sig); 278 else 279 SIGDELSET(ps->ps_sigreset, sig); 280 if (act->sa_flags & SA_NODEFER) 281 SIGADDSET(ps->ps_signodefer, sig); 282 else 283 SIGDELSET(ps->ps_signodefer, sig); 284 #ifdef COMPAT_SUNOS 285 if (act->sa_flags & SA_USERTRAMP) 286 SIGADDSET(ps->ps_usertramp, sig); 287 else 288 SIGDELSET(ps->ps_usertramp, sig); 289 #endif 290 if (sig == SIGCHLD) { 291 if (act->sa_flags & SA_NOCLDSTOP) 292 p->p_procsig->ps_flag |= PS_NOCLDSTOP; 293 else 294 p->p_procsig->ps_flag &= ~PS_NOCLDSTOP; 295 if ((act->sa_flags & SA_NOCLDWAIT) || 296 ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) { 297 /* 298 * Paranoia: since SA_NOCLDWAIT is implemented 299 * by reparenting the dying child to PID 1 (and 300 * trust it to reap the zombie), PID 1 itself 301 * is forbidden to set SA_NOCLDWAIT. 302 */ 303 if (p->p_pid == 1) 304 p->p_procsig->ps_flag &= ~PS_NOCLDWAIT; 305 else 306 p->p_procsig->ps_flag |= PS_NOCLDWAIT; 307 } else 308 p->p_procsig->ps_flag &= ~PS_NOCLDWAIT; 309 } 310 /* 311 * Set bit in p_sigignore for signals that are set to SIG_IGN, 312 * and for signals set to SIG_DFL where the default is to 313 * ignore. However, don't put SIGCONT in p_sigignore, as we 314 * have to restart the process. 315 */ 316 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 317 (sigprop(sig) & SA_IGNORE && 318 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) { 319 /* never to be seen again */ 320 SIGDELSET(p->p_siglist, sig); 321 if (sig != SIGCONT) 322 /* easier in psignal */ 323 SIGADDSET(p->p_sigignore, sig); 324 SIGDELSET(p->p_sigcatch, sig); 325 } else { 326 SIGDELSET(p->p_sigignore, sig); 327 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL) 328 SIGDELSET(p->p_sigcatch, sig); 329 else 330 SIGADDSET(p->p_sigcatch, sig); 331 } 332 #ifdef COMPAT_43 333 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN || 334 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || !old) 335 SIGDELSET(ps->ps_osigset, sig); 336 else 337 SIGADDSET(ps->ps_osigset, sig); 338 #endif 339 } 340 PROC_UNLOCK(p); 341 return (0); 342 } 343 344 #ifndef _SYS_SYSPROTO_H_ 345 struct sigaction_args { 346 int sig; 347 struct sigaction *act; 348 struct sigaction *oact; 349 }; 350 #endif 351 /* 352 * MPSAFE 353 */ 354 /* ARGSUSED */ 355 int 356 sigaction(td, uap) 357 struct thread *td; 358 register struct sigaction_args *uap; 359 { 360 struct proc *p = td->td_proc; 361 struct sigaction act, oact; 362 register struct sigaction *actp, *oactp; 363 int error; 364 365 mtx_lock(&Giant); 366 367 actp = (uap->act != NULL) ? &act : NULL; 368 oactp = (uap->oact != NULL) ? &oact : NULL; 369 if (actp) { 370 error = copyin(uap->act, actp, sizeof(act)); 371 if (error) 372 goto done2; 373 } 374 error = do_sigaction(p, uap->sig, actp, oactp, 0); 375 if (oactp && !error) { 376 error = copyout(oactp, uap->oact, sizeof(oact)); 377 } 378 done2: 379 mtx_unlock(&Giant); 380 return (error); 381 } 382 383 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 384 #ifndef _SYS_SYSPROTO_H_ 385 struct osigaction_args { 386 int signum; 387 struct osigaction *nsa; 388 struct osigaction *osa; 389 }; 390 #endif 391 /* 392 * MPSAFE 393 */ 394 /* ARGSUSED */ 395 int 396 osigaction(td, uap) 397 struct thread *td; 398 register struct osigaction_args *uap; 399 { 400 struct proc *p = td->td_proc; 401 struct osigaction sa; 402 struct sigaction nsa, osa; 403 register struct sigaction *nsap, *osap; 404 int error; 405 406 if (uap->signum <= 0 || uap->signum >= ONSIG) 407 return (EINVAL); 408 409 nsap = (uap->nsa != NULL) ? &nsa : NULL; 410 osap = (uap->osa != NULL) ? &osa : NULL; 411 412 mtx_lock(&Giant); 413 414 if (nsap) { 415 error = copyin(uap->nsa, &sa, sizeof(sa)); 416 if (error) 417 goto done2; 418 nsap->sa_handler = sa.sa_handler; 419 nsap->sa_flags = sa.sa_flags; 420 OSIG2SIG(sa.sa_mask, nsap->sa_mask); 421 } 422 error = do_sigaction(p, uap->signum, nsap, osap, 1); 423 if (osap && !error) { 424 sa.sa_handler = osap->sa_handler; 425 sa.sa_flags = osap->sa_flags; 426 SIG2OSIG(osap->sa_mask, sa.sa_mask); 427 error = copyout(&sa, uap->osa, sizeof(sa)); 428 } 429 done2: 430 mtx_unlock(&Giant); 431 return (error); 432 } 433 #endif /* COMPAT_43 */ 434 435 /* 436 * Initialize signal state for process 0; 437 * set to ignore signals that are ignored by default. 438 */ 439 void 440 siginit(p) 441 struct proc *p; 442 { 443 register int i; 444 445 PROC_LOCK(p); 446 for (i = 1; i <= NSIG; i++) 447 if (sigprop(i) & SA_IGNORE && i != SIGCONT) 448 SIGADDSET(p->p_sigignore, i); 449 PROC_UNLOCK(p); 450 } 451 452 /* 453 * Reset signals for an exec of the specified process. 454 */ 455 void 456 execsigs(p) 457 register struct proc *p; 458 { 459 register struct sigacts *ps; 460 register int sig; 461 462 /* 463 * Reset caught signals. Held signals remain held 464 * through p_sigmask (unless they were caught, 465 * and are now ignored by default). 466 */ 467 PROC_LOCK(p); 468 ps = p->p_sigacts; 469 while (SIGNOTEMPTY(p->p_sigcatch)) { 470 sig = sig_ffs(&p->p_sigcatch); 471 SIGDELSET(p->p_sigcatch, sig); 472 if (sigprop(sig) & SA_IGNORE) { 473 if (sig != SIGCONT) 474 SIGADDSET(p->p_sigignore, sig); 475 SIGDELSET(p->p_siglist, sig); 476 } 477 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 478 } 479 /* 480 * Reset stack state to the user stack. 481 * Clear set of signals caught on the signal stack. 482 */ 483 p->p_sigstk.ss_flags = SS_DISABLE; 484 p->p_sigstk.ss_size = 0; 485 p->p_sigstk.ss_sp = 0; 486 p->p_flag &= ~P_ALTSTACK; 487 /* 488 * Reset no zombies if child dies flag as Solaris does. 489 */ 490 p->p_procsig->ps_flag &= ~PS_NOCLDWAIT; 491 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN) 492 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL; 493 PROC_UNLOCK(p); 494 } 495 496 /* 497 * do_sigprocmask() 498 * 499 * Manipulate signal mask. 500 */ 501 static int 502 do_sigprocmask(p, how, set, oset, old) 503 struct proc *p; 504 int how; 505 sigset_t *set, *oset; 506 int old; 507 { 508 int error; 509 510 PROC_LOCK(p); 511 if (oset != NULL) 512 *oset = p->p_sigmask; 513 514 error = 0; 515 if (set != NULL) { 516 switch (how) { 517 case SIG_BLOCK: 518 SIG_CANTMASK(*set); 519 SIGSETOR(p->p_sigmask, *set); 520 break; 521 case SIG_UNBLOCK: 522 SIGSETNAND(p->p_sigmask, *set); 523 break; 524 case SIG_SETMASK: 525 SIG_CANTMASK(*set); 526 if (old) 527 SIGSETLO(p->p_sigmask, *set); 528 else 529 p->p_sigmask = *set; 530 break; 531 default: 532 error = EINVAL; 533 break; 534 } 535 } 536 PROC_UNLOCK(p); 537 return (error); 538 } 539 540 /* 541 * sigprocmask() - MP SAFE (XXXKSE not under KSE it isn't) 542 */ 543 544 #ifndef _SYS_SYSPROTO_H_ 545 struct sigprocmask_args { 546 int how; 547 const sigset_t *set; 548 sigset_t *oset; 549 }; 550 #endif 551 int 552 sigprocmask(td, uap) 553 register struct thread *td; 554 struct sigprocmask_args *uap; 555 { 556 struct proc *p = td->td_proc; 557 sigset_t set, oset; 558 sigset_t *setp, *osetp; 559 int error; 560 561 setp = (uap->set != NULL) ? &set : NULL; 562 osetp = (uap->oset != NULL) ? &oset : NULL; 563 if (setp) { 564 error = copyin(uap->set, setp, sizeof(set)); 565 if (error) 566 return (error); 567 } 568 error = do_sigprocmask(p, uap->how, setp, osetp, 0); 569 if (osetp && !error) { 570 error = copyout(osetp, uap->oset, sizeof(oset)); 571 } 572 return (error); 573 } 574 575 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 576 /* 577 * osigprocmask() - MP SAFE 578 */ 579 #ifndef _SYS_SYSPROTO_H_ 580 struct osigprocmask_args { 581 int how; 582 osigset_t mask; 583 }; 584 #endif 585 int 586 osigprocmask(td, uap) 587 register struct thread *td; 588 struct osigprocmask_args *uap; 589 { 590 struct proc *p = td->td_proc; 591 sigset_t set, oset; 592 int error; 593 594 OSIG2SIG(uap->mask, set); 595 error = do_sigprocmask(p, uap->how, &set, &oset, 1); 596 SIG2OSIG(oset, td->td_retval[0]); 597 return (error); 598 } 599 #endif /* COMPAT_43 */ 600 601 #ifndef _SYS_SYSPROTO_H_ 602 struct sigpending_args { 603 sigset_t *set; 604 }; 605 #endif 606 /* 607 * MPSAFE 608 */ 609 /* ARGSUSED */ 610 int 611 sigpending(td, uap) 612 struct thread *td; 613 struct sigpending_args *uap; 614 { 615 struct proc *p = td->td_proc; 616 sigset_t siglist; 617 int error; 618 619 mtx_lock(&Giant); 620 PROC_LOCK(p); 621 siglist = p->p_siglist; 622 PROC_UNLOCK(p); 623 mtx_unlock(&Giant); 624 error = copyout(&siglist, uap->set, sizeof(sigset_t)); 625 return(error); 626 } 627 628 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 629 #ifndef _SYS_SYSPROTO_H_ 630 struct osigpending_args { 631 int dummy; 632 }; 633 #endif 634 /* 635 * MPSAFE 636 */ 637 /* ARGSUSED */ 638 int 639 osigpending(td, uap) 640 struct thread *td; 641 struct osigpending_args *uap; 642 { 643 struct proc *p = td->td_proc; 644 645 mtx_lock(&Giant); 646 PROC_LOCK(p); 647 SIG2OSIG(p->p_siglist, td->td_retval[0]); 648 PROC_UNLOCK(p); 649 mtx_unlock(&Giant); 650 return (0); 651 } 652 #endif /* COMPAT_43 */ 653 654 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 655 /* 656 * Generalized interface signal handler, 4.3-compatible. 657 */ 658 #ifndef _SYS_SYSPROTO_H_ 659 struct osigvec_args { 660 int signum; 661 struct sigvec *nsv; 662 struct sigvec *osv; 663 }; 664 #endif 665 /* 666 * MPSAFE 667 */ 668 /* ARGSUSED */ 669 int 670 osigvec(td, uap) 671 struct thread *td; 672 register struct osigvec_args *uap; 673 { 674 struct proc *p = td->td_proc; 675 struct sigvec vec; 676 struct sigaction nsa, osa; 677 register struct sigaction *nsap, *osap; 678 int error; 679 680 if (uap->signum <= 0 || uap->signum >= ONSIG) 681 return (EINVAL); 682 nsap = (uap->nsv != NULL) ? &nsa : NULL; 683 osap = (uap->osv != NULL) ? &osa : NULL; 684 if (nsap) { 685 error = copyin(uap->nsv, &vec, sizeof(vec)); 686 if (error) 687 return (error); 688 nsap->sa_handler = vec.sv_handler; 689 OSIG2SIG(vec.sv_mask, nsap->sa_mask); 690 nsap->sa_flags = vec.sv_flags; 691 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */ 692 #ifdef COMPAT_SUNOS 693 nsap->sa_flags |= SA_USERTRAMP; 694 #endif 695 } 696 mtx_lock(&Giant); 697 error = do_sigaction(p, uap->signum, nsap, osap, 1); 698 mtx_unlock(&Giant); 699 if (osap && !error) { 700 vec.sv_handler = osap->sa_handler; 701 SIG2OSIG(osap->sa_mask, vec.sv_mask); 702 vec.sv_flags = osap->sa_flags; 703 vec.sv_flags &= ~SA_NOCLDWAIT; 704 vec.sv_flags ^= SA_RESTART; 705 #ifdef COMPAT_SUNOS 706 vec.sv_flags &= ~SA_NOCLDSTOP; 707 #endif 708 error = copyout(&vec, uap->osv, sizeof(vec)); 709 } 710 return (error); 711 } 712 713 #ifndef _SYS_SYSPROTO_H_ 714 struct osigblock_args { 715 int mask; 716 }; 717 #endif 718 /* 719 * MPSAFE 720 */ 721 int 722 osigblock(td, uap) 723 register struct thread *td; 724 struct osigblock_args *uap; 725 { 726 struct proc *p = td->td_proc; 727 sigset_t set; 728 729 OSIG2SIG(uap->mask, set); 730 SIG_CANTMASK(set); 731 mtx_lock(&Giant); 732 PROC_LOCK(p); 733 SIG2OSIG(p->p_sigmask, td->td_retval[0]); 734 SIGSETOR(p->p_sigmask, set); 735 PROC_UNLOCK(p); 736 mtx_unlock(&Giant); 737 return (0); 738 } 739 740 #ifndef _SYS_SYSPROTO_H_ 741 struct osigsetmask_args { 742 int mask; 743 }; 744 #endif 745 /* 746 * MPSAFE 747 */ 748 int 749 osigsetmask(td, uap) 750 struct thread *td; 751 struct osigsetmask_args *uap; 752 { 753 struct proc *p = td->td_proc; 754 sigset_t set; 755 756 OSIG2SIG(uap->mask, set); 757 SIG_CANTMASK(set); 758 mtx_lock(&Giant); 759 PROC_LOCK(p); 760 SIG2OSIG(p->p_sigmask, td->td_retval[0]); 761 SIGSETLO(p->p_sigmask, set); 762 PROC_UNLOCK(p); 763 mtx_unlock(&Giant); 764 return (0); 765 } 766 #endif /* COMPAT_43 || COMPAT_SUNOS */ 767 768 /* 769 * Suspend process until signal, providing mask to be set 770 * in the meantime. Note nonstandard calling convention: 771 * libc stub passes mask, not pointer, to save a copyin. 772 ***** XXXKSE this doesn't make sense under KSE. 773 ***** Do we suspend the thread or all threads in the process? 774 ***** How do we suspend threads running NOW on another processor? 775 */ 776 #ifndef _SYS_SYSPROTO_H_ 777 struct sigsuspend_args { 778 const sigset_t *sigmask; 779 }; 780 #endif 781 /* 782 * MPSAFE 783 */ 784 /* ARGSUSED */ 785 int 786 sigsuspend(td, uap) 787 struct thread *td; 788 struct sigsuspend_args *uap; 789 { 790 struct proc *p = td->td_proc; 791 sigset_t mask; 792 register struct sigacts *ps; 793 int error; 794 795 error = copyin(uap->sigmask, &mask, sizeof(mask)); 796 if (error) 797 return (error); 798 799 /* 800 * When returning from sigsuspend, we want 801 * the old mask to be restored after the 802 * signal handler has finished. Thus, we 803 * save it here and mark the sigacts structure 804 * to indicate this. 805 */ 806 mtx_lock(&Giant); 807 PROC_LOCK(p); 808 ps = p->p_sigacts; 809 p->p_oldsigmask = p->p_sigmask; 810 p->p_flag |= P_OLDMASK; 811 812 SIG_CANTMASK(mask); 813 p->p_sigmask = mask; 814 while (msleep((caddr_t) ps, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0) 815 /* void */; 816 PROC_UNLOCK(p); 817 mtx_unlock(&Giant); 818 /* always return EINTR rather than ERESTART... */ 819 return (EINTR); 820 } 821 822 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */ 823 #ifndef _SYS_SYSPROTO_H_ 824 struct osigsuspend_args { 825 osigset_t mask; 826 }; 827 #endif 828 /* 829 * MPSAFE 830 */ 831 /* ARGSUSED */ 832 int 833 osigsuspend(td, uap) 834 struct thread *td; 835 struct osigsuspend_args *uap; 836 { 837 struct proc *p = td->td_proc; 838 sigset_t mask; 839 register struct sigacts *ps; 840 841 mtx_lock(&Giant); 842 PROC_LOCK(p); 843 ps = p->p_sigacts; 844 p->p_oldsigmask = p->p_sigmask; 845 p->p_flag |= P_OLDMASK; 846 OSIG2SIG(uap->mask, mask); 847 SIG_CANTMASK(mask); 848 SIGSETLO(p->p_sigmask, mask); 849 while (msleep((caddr_t) ps, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0) 850 /* void */; 851 PROC_UNLOCK(p); 852 mtx_unlock(&Giant); 853 /* always return EINTR rather than ERESTART... */ 854 return (EINTR); 855 } 856 #endif /* COMPAT_43 */ 857 858 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 859 #ifndef _SYS_SYSPROTO_H_ 860 struct osigstack_args { 861 struct sigstack *nss; 862 struct sigstack *oss; 863 }; 864 #endif 865 /* 866 * MPSAFE 867 */ 868 /* ARGSUSED */ 869 int 870 osigstack(td, uap) 871 struct thread *td; 872 register struct osigstack_args *uap; 873 { 874 struct proc *p = td->td_proc; 875 struct sigstack ss; 876 int error = 0; 877 878 mtx_lock(&Giant); 879 880 if (uap->oss != NULL) { 881 PROC_LOCK(p); 882 ss.ss_sp = p->p_sigstk.ss_sp; 883 ss.ss_onstack = sigonstack(cpu_getstack(td)); 884 PROC_UNLOCK(p); 885 error = copyout(&ss, uap->oss, sizeof(struct sigstack)); 886 if (error) 887 goto done2; 888 } 889 890 if (uap->nss != NULL) { 891 if ((error = copyin(uap->nss, &ss, sizeof(ss))) != 0) 892 goto done2; 893 PROC_LOCK(p); 894 p->p_sigstk.ss_sp = ss.ss_sp; 895 p->p_sigstk.ss_size = 0; 896 p->p_sigstk.ss_flags |= ss.ss_onstack & SS_ONSTACK; 897 p->p_flag |= P_ALTSTACK; 898 PROC_UNLOCK(p); 899 } 900 done2: 901 mtx_unlock(&Giant); 902 return (error); 903 } 904 #endif /* COMPAT_43 || COMPAT_SUNOS */ 905 906 #ifndef _SYS_SYSPROTO_H_ 907 struct sigaltstack_args { 908 stack_t *ss; 909 stack_t *oss; 910 }; 911 #endif 912 /* 913 * MPSAFE 914 */ 915 /* ARGSUSED */ 916 int 917 sigaltstack(td, uap) 918 struct thread *td; 919 register struct sigaltstack_args *uap; 920 { 921 struct proc *p = td->td_proc; 922 stack_t ss; 923 int oonstack; 924 int error = 0; 925 926 mtx_lock(&Giant); 927 928 oonstack = sigonstack(cpu_getstack(td)); 929 930 if (uap->oss != NULL) { 931 PROC_LOCK(p); 932 ss = p->p_sigstk; 933 ss.ss_flags = (p->p_flag & P_ALTSTACK) 934 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE; 935 PROC_UNLOCK(p); 936 if ((error = copyout(&ss, uap->oss, sizeof(stack_t))) != 0) 937 goto done2; 938 } 939 940 if (uap->ss != NULL) { 941 if (oonstack) { 942 error = EPERM; 943 goto done2; 944 } 945 if ((error = copyin(uap->ss, &ss, sizeof(ss))) != 0) 946 goto done2; 947 if ((ss.ss_flags & ~SS_DISABLE) != 0) { 948 error = EINVAL; 949 goto done2; 950 } 951 if (!(ss.ss_flags & SS_DISABLE)) { 952 if (ss.ss_size < p->p_sysent->sv_minsigstksz) { 953 error = ENOMEM; 954 goto done2; 955 } 956 PROC_LOCK(p); 957 p->p_sigstk = ss; 958 p->p_flag |= P_ALTSTACK; 959 PROC_UNLOCK(p); 960 } else { 961 PROC_LOCK(p); 962 p->p_flag &= ~P_ALTSTACK; 963 PROC_UNLOCK(p); 964 } 965 } 966 done2: 967 mtx_unlock(&Giant); 968 return (error); 969 } 970 971 /* 972 * Common code for kill process group/broadcast kill. 973 * cp is calling process. 974 */ 975 int 976 killpg1(cp, sig, pgid, all) 977 register struct proc *cp; 978 int sig, pgid, all; 979 { 980 register struct proc *p; 981 struct pgrp *pgrp; 982 int nfound = 0; 983 984 if (all) { 985 /* 986 * broadcast 987 */ 988 sx_slock(&allproc_lock); 989 LIST_FOREACH(p, &allproc, p_list) { 990 PROC_LOCK(p); 991 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM || p == cp) { 992 PROC_UNLOCK(p); 993 continue; 994 } 995 if (p_cansignal(cp, p, sig) == 0) { 996 nfound++; 997 if (sig) 998 psignal(p, sig); 999 } 1000 PROC_UNLOCK(p); 1001 } 1002 sx_sunlock(&allproc_lock); 1003 } else { 1004 if (pgid == 0) 1005 /* 1006 * zero pgid means send to my process group. 1007 */ 1008 pgrp = cp->p_pgrp; 1009 else { 1010 pgrp = pgfind(pgid); 1011 if (pgrp == NULL) 1012 return (ESRCH); 1013 } 1014 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1015 PROC_LOCK(p); 1016 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM) { 1017 PROC_UNLOCK(p); 1018 continue; 1019 } 1020 mtx_lock_spin(&sched_lock); 1021 if (p->p_stat == SZOMB) { 1022 mtx_unlock_spin(&sched_lock); 1023 PROC_UNLOCK(p); 1024 continue; 1025 } 1026 mtx_unlock_spin(&sched_lock); 1027 if (p_cansignal(cp, p, sig) == 0) { 1028 nfound++; 1029 if (sig) 1030 psignal(p, sig); 1031 } 1032 PROC_UNLOCK(p); 1033 } 1034 } 1035 return (nfound ? 0 : ESRCH); 1036 } 1037 1038 #ifndef _SYS_SYSPROTO_H_ 1039 struct kill_args { 1040 int pid; 1041 int signum; 1042 }; 1043 #endif 1044 /* 1045 * MPSAFE 1046 */ 1047 /* ARGSUSED */ 1048 int 1049 kill(td, uap) 1050 register struct thread *td; 1051 register struct kill_args *uap; 1052 { 1053 register struct proc *cp = td->td_proc; 1054 register struct proc *p; 1055 int error = 0; 1056 1057 if ((u_int)uap->signum > _SIG_MAXSIG) 1058 return (EINVAL); 1059 1060 mtx_lock(&Giant); 1061 if (uap->pid > 0) { 1062 /* kill single process */ 1063 if ((p = pfind(uap->pid)) == NULL) { 1064 error = ESRCH; 1065 } else if (p_cansignal(cp, p, uap->signum)) { 1066 PROC_UNLOCK(p); 1067 error = EPERM; 1068 } else { 1069 if (uap->signum) 1070 psignal(p, uap->signum); 1071 PROC_UNLOCK(p); 1072 error = 0; 1073 } 1074 } else { 1075 switch (uap->pid) { 1076 case -1: /* broadcast signal */ 1077 error = killpg1(cp, uap->signum, 0, 1); 1078 break; 1079 case 0: /* signal own process group */ 1080 error = killpg1(cp, uap->signum, 0, 0); 1081 break; 1082 default: /* negative explicit process group */ 1083 error = killpg1(cp, uap->signum, -uap->pid, 0); 1084 break; 1085 } 1086 } 1087 mtx_unlock(&Giant); 1088 return(error); 1089 } 1090 1091 #if defined(COMPAT_43) || defined(COMPAT_SUNOS) 1092 #ifndef _SYS_SYSPROTO_H_ 1093 struct okillpg_args { 1094 int pgid; 1095 int signum; 1096 }; 1097 #endif 1098 /* 1099 * MPSAFE 1100 */ 1101 /* ARGSUSED */ 1102 int 1103 okillpg(td, uap) 1104 struct thread *td; 1105 register struct okillpg_args *uap; 1106 { 1107 int error; 1108 1109 if ((u_int)uap->signum > _SIG_MAXSIG) 1110 return (EINVAL); 1111 mtx_lock(&Giant); 1112 error = killpg1(td->td_proc, uap->signum, uap->pgid, 0); 1113 mtx_unlock(&Giant); 1114 return (error); 1115 } 1116 #endif /* COMPAT_43 || COMPAT_SUNOS */ 1117 1118 /* 1119 * Send a signal to a process group. 1120 */ 1121 void 1122 gsignal(pgid, sig) 1123 int pgid, sig; 1124 { 1125 struct pgrp *pgrp; 1126 1127 if (pgid && (pgrp = pgfind(pgid))) 1128 pgsignal(pgrp, sig, 0); 1129 } 1130 1131 /* 1132 * Send a signal to a process group. If checktty is 1, 1133 * limit to members which have a controlling terminal. 1134 */ 1135 void 1136 pgsignal(pgrp, sig, checkctty) 1137 struct pgrp *pgrp; 1138 int sig, checkctty; 1139 { 1140 register struct proc *p; 1141 1142 if (pgrp) { 1143 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) { 1144 PROC_LOCK(p); 1145 if (checkctty == 0 || p->p_flag & P_CONTROLT) 1146 psignal(p, sig); 1147 PROC_UNLOCK(p); 1148 } 1149 } 1150 } 1151 1152 /* 1153 * Send a signal caused by a trap to the current process. 1154 * If it will be caught immediately, deliver it with correct code. 1155 * Otherwise, post it normally. 1156 * 1157 * MPSAFE 1158 */ 1159 void 1160 trapsignal(p, sig, code) 1161 struct proc *p; 1162 register int sig; 1163 u_long code; 1164 { 1165 register struct sigacts *ps = p->p_sigacts; 1166 1167 mtx_lock(&Giant); 1168 PROC_LOCK(p); 1169 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(p->p_sigcatch, sig) && 1170 !SIGISMEMBER(p->p_sigmask, sig)) { 1171 p->p_stats->p_ru.ru_nsignals++; 1172 #ifdef KTRACE 1173 if (KTRPOINT(p, KTR_PSIG)) 1174 ktrpsig(p->p_tracep, sig, ps->ps_sigact[_SIG_IDX(sig)], 1175 &p->p_sigmask, code); 1176 #endif 1177 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)], sig, 1178 &p->p_sigmask, code); 1179 SIGSETOR(p->p_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 1180 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 1181 SIGADDSET(p->p_sigmask, sig); 1182 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 1183 /* 1184 * See do_sigaction() for origin of this code. 1185 */ 1186 SIGDELSET(p->p_sigcatch, sig); 1187 if (sig != SIGCONT && 1188 sigprop(sig) & SA_IGNORE) 1189 SIGADDSET(p->p_sigignore, sig); 1190 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 1191 } 1192 } else { 1193 p->p_code = code; /* XXX for core dump/debugger */ 1194 p->p_sig = sig; /* XXX to verify code */ 1195 psignal(p, sig); 1196 } 1197 PROC_UNLOCK(p); 1198 mtx_unlock(&Giant); 1199 } 1200 1201 /* 1202 * Send the signal to the process. If the signal has an action, the action 1203 * is usually performed by the target process rather than the caller; we add 1204 * the signal to the set of pending signals for the process. 1205 * 1206 * Exceptions: 1207 * o When a stop signal is sent to a sleeping process that takes the 1208 * default action, the process is stopped without awakening it. 1209 * o SIGCONT restarts stopped processes (or puts them back to sleep) 1210 * regardless of the signal action (eg, blocked or ignored). 1211 * 1212 * Other ignored signals are discarded immediately. 1213 */ 1214 void 1215 psignal(p, sig) 1216 register struct proc *p; 1217 register int sig; 1218 { 1219 register int prop; 1220 register sig_t action; 1221 struct thread *td; 1222 struct ksegrp *kg; 1223 1224 KASSERT(_SIG_VALID(sig), 1225 ("psignal(): invalid signal %d\n", sig)); 1226 1227 PROC_LOCK_ASSERT(p, MA_OWNED); 1228 KNOTE(&p->p_klist, NOTE_SIGNAL | sig); 1229 1230 prop = sigprop(sig); 1231 1232 /* 1233 * If proc is traced, always give parent a chance; 1234 * if signal event is tracked by procfs, give *that* 1235 * a chance, as well. 1236 */ 1237 if ((p->p_flag & P_TRACED) || (p->p_stops & S_SIG)) { 1238 action = SIG_DFL; 1239 } else { 1240 /* 1241 * If the signal is being ignored, 1242 * then we forget about it immediately. 1243 * (Note: we don't set SIGCONT in p_sigignore, 1244 * and if it is set to SIG_IGN, 1245 * action will be SIG_DFL here.) 1246 */ 1247 if (SIGISMEMBER(p->p_sigignore, sig) || (p->p_flag & P_WEXIT)) 1248 return; 1249 if (SIGISMEMBER(p->p_sigmask, sig)) 1250 action = SIG_HOLD; 1251 else if (SIGISMEMBER(p->p_sigcatch, sig)) 1252 action = SIG_CATCH; 1253 else 1254 action = SIG_DFL; 1255 } 1256 1257 /* 1258 * bring the priority of a process up if we want it to get 1259 * killed in this lifetime. 1260 * XXXKSE think if a better way to do this. 1261 * 1262 * What we need to do is see if there is a thread that will 1263 * be able to accept the signal. e.g. 1264 * FOREACH_THREAD_IN_PROC() { 1265 * if runnable, we're done 1266 * else pick one at random. 1267 * } 1268 */ 1269 /* XXXKSE 1270 * For now there is one thread per proc. 1271 * Effectively select one sucker thread.. 1272 */ 1273 td = FIRST_THREAD_IN_PROC(p); 1274 mtx_lock_spin(&sched_lock); 1275 if ((p->p_ksegrp.kg_nice > NZERO) && (action == SIG_DFL) && 1276 (prop & SA_KILL) && ((p->p_flag & P_TRACED) == 0)) 1277 p->p_ksegrp.kg_nice = NZERO; /* XXXKSE */ 1278 mtx_unlock_spin(&sched_lock); 1279 1280 if (prop & SA_CONT) 1281 SIG_STOPSIGMASK(p->p_siglist); 1282 1283 if (prop & SA_STOP) { 1284 /* 1285 * If sending a tty stop signal to a member of an orphaned 1286 * process group, discard the signal here if the action 1287 * is default; don't stop the process below if sleeping, 1288 * and don't clear any pending SIGCONT. 1289 */ 1290 if (prop & SA_TTYSTOP && p->p_pgrp->pg_jobc == 0 && 1291 action == SIG_DFL) 1292 return; 1293 SIG_CONTSIGMASK(p->p_siglist); 1294 } 1295 SIGADDSET(p->p_siglist, sig); 1296 1297 /* 1298 * Defer further processing for signals which are held, 1299 * except that stopped processes must be continued by SIGCONT. 1300 */ 1301 mtx_lock_spin(&sched_lock); 1302 if (action == SIG_HOLD && (!(prop & SA_CONT) || p->p_stat != SSTOP)) { 1303 mtx_unlock_spin(&sched_lock); 1304 return; 1305 } 1306 1307 switch (p->p_stat) { 1308 1309 case SSLEEP: 1310 /* 1311 * If process is sleeping uninterruptibly 1312 * we can't interrupt the sleep... the signal will 1313 * be noticed when the process returns through 1314 * trap() or syscall(). 1315 */ 1316 if ((td->td_flags & TDF_SINTR) == 0) { 1317 mtx_unlock_spin(&sched_lock); 1318 goto out; 1319 } 1320 /* 1321 * Process is sleeping and traced... make it runnable 1322 * so it can discover the signal in issignal() and stop 1323 * for the parent. 1324 */ 1325 if (p->p_flag & P_TRACED) 1326 goto run; 1327 mtx_unlock_spin(&sched_lock); 1328 /* 1329 * If SIGCONT is default (or ignored) and process is 1330 * asleep, we are finished; the process should not 1331 * be awakened. 1332 */ 1333 if ((prop & SA_CONT) && action == SIG_DFL) { 1334 SIGDELSET(p->p_siglist, sig); 1335 goto out; 1336 } 1337 /* 1338 * When a sleeping process receives a stop 1339 * signal, process immediately if possible. 1340 * All other (caught or default) signals 1341 * cause the process to run. 1342 */ 1343 if (prop & SA_STOP) { 1344 if (action != SIG_DFL) 1345 goto runfast; 1346 /* 1347 * If a child holding parent blocked, 1348 * stopping could cause deadlock. 1349 */ 1350 if (p->p_flag & P_PPWAIT) 1351 goto out; 1352 SIGDELSET(p->p_siglist, sig); 1353 p->p_xstat = sig; 1354 if ((p->p_pptr->p_procsig->ps_flag & PS_NOCLDSTOP) == 0) { 1355 PROC_LOCK(p->p_pptr); 1356 psignal(p->p_pptr, SIGCHLD); 1357 PROC_UNLOCK(p->p_pptr); 1358 } 1359 mtx_lock_spin(&sched_lock); 1360 stop(p); 1361 mtx_unlock_spin(&sched_lock); 1362 goto out; 1363 } else 1364 goto runfast; 1365 /* NOTREACHED */ 1366 1367 case SSTOP: 1368 mtx_unlock_spin(&sched_lock); 1369 /* 1370 * If traced process is already stopped, 1371 * then no further action is necessary. 1372 */ 1373 if (p->p_flag & P_TRACED) 1374 goto out; 1375 1376 /* 1377 * Kill signal always sets processes running. 1378 */ 1379 if (sig == SIGKILL) 1380 goto runfast; 1381 1382 if (prop & SA_CONT) { 1383 /* 1384 * If SIGCONT is default (or ignored), we continue the 1385 * process but don't leave the signal in p_siglist, as 1386 * it has no further action. If SIGCONT is held, we 1387 * continue the process and leave the signal in 1388 * p_siglist. If the process catches SIGCONT, let it 1389 * handle the signal itself. If it isn't waiting on 1390 * an event, then it goes back to run state. 1391 * Otherwise, process goes back to sleep state. 1392 */ 1393 if (action == SIG_DFL) 1394 SIGDELSET(p->p_siglist, sig); 1395 if (action == SIG_CATCH) 1396 goto runfast; 1397 mtx_lock_spin(&sched_lock); 1398 /* 1399 * XXXKSE 1400 * do this for each thread. 1401 */ 1402 if (p->p_flag & P_KSES) { 1403 mtx_assert(&sched_lock, 1404 MA_OWNED | MA_NOTRECURSED); 1405 FOREACH_THREAD_IN_PROC(p, td) { 1406 if (td->td_wchan == NULL) { 1407 setrunnable(td); /* XXXKSE */ 1408 } else { 1409 /* mark it as sleeping */ 1410 } 1411 } 1412 mtx_unlock_spin(&sched_lock); 1413 } else { 1414 if (td->td_wchan == NULL) 1415 goto run; 1416 p->p_stat = SSLEEP; 1417 mtx_unlock_spin(&sched_lock); 1418 } 1419 goto out; 1420 } 1421 1422 if (prop & SA_STOP) { 1423 /* 1424 * Already stopped, don't need to stop again. 1425 * (If we did the shell could get confused.) 1426 */ 1427 SIGDELSET(p->p_siglist, sig); 1428 goto out; 1429 } 1430 1431 /* 1432 * If process is sleeping interruptibly, then simulate a 1433 * wakeup so that when it is continued, it will be made 1434 * runnable and can look at the signal. But don't make 1435 * the process runnable, leave it stopped. 1436 * XXXKSE should we wake ALL blocked threads? 1437 */ 1438 mtx_lock_spin(&sched_lock); 1439 if (p->p_flag & P_KSES) { 1440 FOREACH_THREAD_IN_PROC(p, td) { 1441 if (td->td_wchan && (td->td_flags & TDF_SINTR)){ 1442 if (td->td_flags & TDF_CVWAITQ) 1443 cv_waitq_remove(td); 1444 else 1445 unsleep(td); /* XXXKSE */ 1446 } 1447 } 1448 } else { 1449 if (td->td_wchan && td->td_flags & TDF_SINTR) { 1450 if (td->td_flags & TDF_CVWAITQ) 1451 cv_waitq_remove(td); 1452 else 1453 unsleep(td); /* XXXKSE */ 1454 } 1455 } 1456 mtx_unlock_spin(&sched_lock); 1457 goto out; 1458 1459 default: 1460 /* 1461 * SRUN, SIDL, SZOMB do nothing with the signal, 1462 * other than kicking ourselves if we are running. 1463 * It will either never be noticed, or noticed very soon. 1464 */ 1465 if (p->p_stat == SRUN) { 1466 #ifdef SMP 1467 struct kse *ke; 1468 struct thread *td = curthread; 1469 signotify(&p->p_kse); /* XXXKSE */ 1470 /* we should only deliver to one thread.. but which one? */ 1471 FOREACH_KSEGRP_IN_PROC(p, kg) { 1472 FOREACH_KSE_IN_GROUP(kg, ke) { 1473 if (ke->ke_thread == td) { 1474 continue; 1475 } 1476 forward_signal(ke->ke_thread); 1477 } 1478 } 1479 #else 1480 signotify(&p->p_kse); /* XXXKSE */ 1481 #endif 1482 } 1483 mtx_unlock_spin(&sched_lock); 1484 goto out; 1485 } 1486 /*NOTREACHED*/ 1487 1488 runfast: 1489 /* 1490 * Raise priority to at least PUSER. 1491 * XXXKSE Should we make them all run fast? 1492 * Maybe just one would be enough? 1493 */ 1494 mtx_lock_spin(&sched_lock); 1495 1496 if (FIRST_THREAD_IN_PROC(p)->td_priority > PUSER) { 1497 FIRST_THREAD_IN_PROC(p)->td_priority = PUSER; 1498 } 1499 run: 1500 /* If we jump here, sched_lock has to be owned. */ 1501 mtx_assert(&sched_lock, MA_OWNED | MA_NOTRECURSED); 1502 setrunnable(td); /* XXXKSE */ 1503 mtx_unlock_spin(&sched_lock); 1504 out: 1505 /* If we jump here, sched_lock should not be owned. */ 1506 mtx_assert(&sched_lock, MA_NOTOWNED); 1507 } 1508 1509 /* 1510 * If the current process has received a signal (should be caught or cause 1511 * termination, should interrupt current syscall), return the signal number. 1512 * Stop signals with default action are processed immediately, then cleared; 1513 * they aren't returned. This is checked after each entry to the system for 1514 * a syscall or trap (though this can usually be done without calling issignal 1515 * by checking the pending signal masks in the CURSIG macro.) The normal call 1516 * sequence is 1517 * 1518 * while (sig = CURSIG(curproc)) 1519 * postsig(sig); 1520 */ 1521 int 1522 issignal(p) 1523 register struct proc *p; 1524 { 1525 sigset_t mask; 1526 register int sig, prop; 1527 1528 PROC_LOCK_ASSERT(p, MA_OWNED); 1529 for (;;) { 1530 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG); 1531 1532 mask = p->p_siglist; 1533 SIGSETNAND(mask, p->p_sigmask); 1534 if (p->p_flag & P_PPWAIT) 1535 SIG_STOPSIGMASK(mask); 1536 if (!SIGNOTEMPTY(mask)) /* no signal to send */ 1537 return (0); 1538 sig = sig_ffs(&mask); 1539 prop = sigprop(sig); 1540 1541 _STOPEVENT(p, S_SIG, sig); 1542 1543 /* 1544 * We should see pending but ignored signals 1545 * only if P_TRACED was on when they were posted. 1546 */ 1547 if (SIGISMEMBER(p->p_sigignore, sig) && (traced == 0)) { 1548 SIGDELSET(p->p_siglist, sig); 1549 continue; 1550 } 1551 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) { 1552 /* 1553 * If traced, always stop, and stay 1554 * stopped until released by the parent. 1555 */ 1556 p->p_xstat = sig; 1557 PROC_LOCK(p->p_pptr); 1558 psignal(p->p_pptr, SIGCHLD); 1559 PROC_UNLOCK(p->p_pptr); 1560 do { 1561 mtx_lock_spin(&sched_lock); 1562 stop(p); 1563 PROC_UNLOCK(p); 1564 DROP_GIANT(); 1565 p->p_stats->p_ru.ru_nivcsw++; 1566 mi_switch(); 1567 mtx_unlock_spin(&sched_lock); 1568 PICKUP_GIANT(); 1569 PROC_LOCK(p); 1570 } while (!trace_req(p) 1571 && p->p_flag & P_TRACED); 1572 1573 /* 1574 * If the traced bit got turned off, go back up 1575 * to the top to rescan signals. This ensures 1576 * that p_sig* and ps_sigact are consistent. 1577 */ 1578 if ((p->p_flag & P_TRACED) == 0) 1579 continue; 1580 1581 /* 1582 * If parent wants us to take the signal, 1583 * then it will leave it in p->p_xstat; 1584 * otherwise we just look for signals again. 1585 */ 1586 SIGDELSET(p->p_siglist, sig); /* clear old signal */ 1587 sig = p->p_xstat; 1588 if (sig == 0) 1589 continue; 1590 1591 /* 1592 * Put the new signal into p_siglist. If the 1593 * signal is being masked, look for other signals. 1594 */ 1595 SIGADDSET(p->p_siglist, sig); 1596 if (SIGISMEMBER(p->p_sigmask, sig)) 1597 continue; 1598 } 1599 1600 /* 1601 * Decide whether the signal should be returned. 1602 * Return the signal's number, or fall through 1603 * to clear it from the pending mask. 1604 */ 1605 switch ((int)(intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) { 1606 1607 case (int)SIG_DFL: 1608 /* 1609 * Don't take default actions on system processes. 1610 */ 1611 if (p->p_pid <= 1) { 1612 #ifdef DIAGNOSTIC 1613 /* 1614 * Are you sure you want to ignore SIGSEGV 1615 * in init? XXX 1616 */ 1617 printf("Process (pid %lu) got signal %d\n", 1618 (u_long)p->p_pid, sig); 1619 #endif 1620 break; /* == ignore */ 1621 } 1622 /* 1623 * If there is a pending stop signal to process 1624 * with default action, stop here, 1625 * then clear the signal. However, 1626 * if process is member of an orphaned 1627 * process group, ignore tty stop signals. 1628 */ 1629 if (prop & SA_STOP) { 1630 if (p->p_flag & P_TRACED || 1631 (p->p_pgrp->pg_jobc == 0 && 1632 prop & SA_TTYSTOP)) 1633 break; /* == ignore */ 1634 p->p_xstat = sig; 1635 if ((p->p_pptr->p_procsig->ps_flag & PS_NOCLDSTOP) == 0) { 1636 PROC_LOCK(p->p_pptr); 1637 psignal(p->p_pptr, SIGCHLD); 1638 PROC_UNLOCK(p->p_pptr); 1639 } 1640 mtx_lock_spin(&sched_lock); 1641 stop(p); 1642 PROC_UNLOCK(p); 1643 DROP_GIANT(); 1644 p->p_stats->p_ru.ru_nivcsw++; 1645 mi_switch(); 1646 mtx_unlock_spin(&sched_lock); 1647 PICKUP_GIANT(); 1648 PROC_LOCK(p); 1649 break; 1650 } else if (prop & SA_IGNORE) { 1651 /* 1652 * Except for SIGCONT, shouldn't get here. 1653 * Default action is to ignore; drop it. 1654 */ 1655 break; /* == ignore */ 1656 } else 1657 return (sig); 1658 /*NOTREACHED*/ 1659 1660 case (int)SIG_IGN: 1661 /* 1662 * Masking above should prevent us ever trying 1663 * to take action on an ignored signal other 1664 * than SIGCONT, unless process is traced. 1665 */ 1666 if ((prop & SA_CONT) == 0 && 1667 (p->p_flag & P_TRACED) == 0) 1668 printf("issignal\n"); 1669 break; /* == ignore */ 1670 1671 default: 1672 /* 1673 * This signal has an action, let 1674 * postsig() process it. 1675 */ 1676 return (sig); 1677 } 1678 SIGDELSET(p->p_siglist, sig); /* take the signal! */ 1679 } 1680 /* NOTREACHED */ 1681 } 1682 1683 /* 1684 * Put the argument process into the stopped state and notify the parent 1685 * via wakeup. Signals are handled elsewhere. The process must not be 1686 * on the run queue. Must be called with the proc p locked and the scheduler 1687 * lock held. 1688 */ 1689 static void 1690 stop(p) 1691 register struct proc *p; 1692 { 1693 1694 PROC_LOCK_ASSERT(p, MA_OWNED); 1695 mtx_assert(&sched_lock, MA_OWNED); 1696 p->p_stat = SSTOP; 1697 p->p_flag &= ~P_WAITED; 1698 wakeup((caddr_t)p->p_pptr); 1699 } 1700 1701 /* 1702 * Take the action for the specified signal 1703 * from the current set of pending signals. 1704 */ 1705 void 1706 postsig(sig) 1707 register int sig; 1708 { 1709 struct thread *td = curthread; 1710 register struct proc *p = td->td_proc; 1711 struct sigacts *ps; 1712 sig_t action; 1713 sigset_t returnmask; 1714 int code; 1715 1716 KASSERT(sig != 0, ("postsig")); 1717 1718 PROC_LOCK_ASSERT(p, MA_OWNED); 1719 ps = p->p_sigacts; 1720 SIGDELSET(p->p_siglist, sig); 1721 action = ps->ps_sigact[_SIG_IDX(sig)]; 1722 #ifdef KTRACE 1723 if (KTRPOINT(p, KTR_PSIG)) 1724 ktrpsig(p->p_tracep, sig, action, p->p_flag & P_OLDMASK ? 1725 &p->p_oldsigmask : &p->p_sigmask, 0); 1726 #endif 1727 _STOPEVENT(p, S_SIG, sig); 1728 1729 if (action == SIG_DFL) { 1730 /* 1731 * Default action, where the default is to kill 1732 * the process. (Other cases were ignored above.) 1733 */ 1734 sigexit(td, sig); 1735 /* NOTREACHED */ 1736 } else { 1737 /* 1738 * If we get here, the signal must be caught. 1739 */ 1740 KASSERT(action != SIG_IGN && !SIGISMEMBER(p->p_sigmask, sig), 1741 ("postsig action")); 1742 /* 1743 * Set the new mask value and also defer further 1744 * occurrences of this signal. 1745 * 1746 * Special case: user has done a sigsuspend. Here the 1747 * current mask is not of interest, but rather the 1748 * mask from before the sigsuspend is what we want 1749 * restored after the signal processing is completed. 1750 */ 1751 if (p->p_flag & P_OLDMASK) { 1752 returnmask = p->p_oldsigmask; 1753 p->p_flag &= ~P_OLDMASK; 1754 } else 1755 returnmask = p->p_sigmask; 1756 1757 SIGSETOR(p->p_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]); 1758 if (!SIGISMEMBER(ps->ps_signodefer, sig)) 1759 SIGADDSET(p->p_sigmask, sig); 1760 1761 if (SIGISMEMBER(ps->ps_sigreset, sig)) { 1762 /* 1763 * See do_sigaction() for origin of this code. 1764 */ 1765 SIGDELSET(p->p_sigcatch, sig); 1766 if (sig != SIGCONT && 1767 sigprop(sig) & SA_IGNORE) 1768 SIGADDSET(p->p_sigignore, sig); 1769 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL; 1770 } 1771 p->p_stats->p_ru.ru_nsignals++; 1772 if (p->p_sig != sig) { 1773 code = 0; 1774 } else { 1775 code = p->p_code; 1776 p->p_code = 0; 1777 p->p_sig = 0; 1778 } 1779 (*p->p_sysent->sv_sendsig)(action, sig, &returnmask, code); 1780 } 1781 } 1782 1783 /* 1784 * Kill the current process for stated reason. 1785 */ 1786 void 1787 killproc(p, why) 1788 struct proc *p; 1789 char *why; 1790 { 1791 1792 PROC_LOCK_ASSERT(p, MA_OWNED); 1793 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", 1794 p, p->p_pid, p->p_comm); 1795 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm, 1796 p->p_ucred ? p->p_ucred->cr_uid : -1, why); 1797 psignal(p, SIGKILL); 1798 } 1799 1800 /* 1801 * Force the current process to exit with the specified signal, dumping core 1802 * if appropriate. We bypass the normal tests for masked and caught signals, 1803 * allowing unrecoverable failures to terminate the process without changing 1804 * signal state. Mark the accounting record with the signal termination. 1805 * If dumping core, save the signal number for the debugger. Calls exit and 1806 * does not return. 1807 */ 1808 void 1809 sigexit(td, sig) 1810 struct thread *td; 1811 int sig; 1812 { 1813 struct proc *p = td->td_proc; 1814 1815 PROC_LOCK_ASSERT(p, MA_OWNED); 1816 p->p_acflag |= AXSIG; 1817 if (sigprop(sig) & SA_CORE) { 1818 p->p_sig = sig; 1819 /* 1820 * Log signals which would cause core dumps 1821 * (Log as LOG_INFO to appease those who don't want 1822 * these messages.) 1823 * XXX : Todo, as well as euid, write out ruid too 1824 */ 1825 PROC_UNLOCK(p); 1826 if (!mtx_owned(&Giant)) 1827 mtx_lock(&Giant); 1828 if (coredump(td) == 0) 1829 sig |= WCOREFLAG; 1830 if (kern_logsigexit) 1831 log(LOG_INFO, 1832 "pid %d (%s), uid %d: exited on signal %d%s\n", 1833 p->p_pid, p->p_comm, 1834 p->p_ucred ? p->p_ucred->cr_uid : -1, 1835 sig &~ WCOREFLAG, 1836 sig & WCOREFLAG ? " (core dumped)" : ""); 1837 } else { 1838 PROC_UNLOCK(p); 1839 if (!mtx_owned(&Giant)) 1840 mtx_lock(&Giant); 1841 } 1842 exit1(td, W_EXITCODE(0, sig)); 1843 /* NOTREACHED */ 1844 } 1845 1846 static char corefilename[MAXPATHLEN+1] = {"%N.core"}; 1847 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename, 1848 sizeof(corefilename), "process corefile name format string"); 1849 1850 /* 1851 * expand_name(name, uid, pid) 1852 * Expand the name described in corefilename, using name, uid, and pid. 1853 * corefilename is a printf-like string, with three format specifiers: 1854 * %N name of process ("name") 1855 * %P process id (pid) 1856 * %U user id (uid) 1857 * For example, "%N.core" is the default; they can be disabled completely 1858 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P". 1859 * This is controlled by the sysctl variable kern.corefile (see above). 1860 */ 1861 1862 static char * 1863 expand_name(name, uid, pid) 1864 const char *name; uid_t uid; pid_t pid; { 1865 char *temp; 1866 char buf[11]; /* Buffer for pid/uid -- max 4B */ 1867 int i, n; 1868 char *format = corefilename; 1869 size_t namelen; 1870 1871 temp = malloc(MAXPATHLEN + 1, M_TEMP, M_NOWAIT); 1872 if (temp == NULL) 1873 return NULL; 1874 namelen = strlen(name); 1875 for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) { 1876 int l; 1877 switch (format[i]) { 1878 case '%': /* Format character */ 1879 i++; 1880 switch (format[i]) { 1881 case '%': 1882 temp[n++] = '%'; 1883 break; 1884 case 'N': /* process name */ 1885 if ((n + namelen) > MAXPATHLEN) { 1886 log(LOG_ERR, "pid %d (%s), uid (%u): Path `%s%s' is too long\n", 1887 pid, name, uid, temp, name); 1888 free(temp, M_TEMP); 1889 return NULL; 1890 } 1891 memcpy(temp+n, name, namelen); 1892 n += namelen; 1893 break; 1894 case 'P': /* process id */ 1895 l = sprintf(buf, "%u", pid); 1896 if ((n + l) > MAXPATHLEN) { 1897 log(LOG_ERR, "pid %d (%s), uid (%u): Path `%s%s' is too long\n", 1898 pid, name, uid, temp, name); 1899 free(temp, M_TEMP); 1900 return NULL; 1901 } 1902 memcpy(temp+n, buf, l); 1903 n += l; 1904 break; 1905 case 'U': /* user id */ 1906 l = sprintf(buf, "%u", uid); 1907 if ((n + l) > MAXPATHLEN) { 1908 log(LOG_ERR, "pid %d (%s), uid (%u): Path `%s%s' is too long\n", 1909 pid, name, uid, temp, name); 1910 free(temp, M_TEMP); 1911 return NULL; 1912 } 1913 memcpy(temp+n, buf, l); 1914 n += l; 1915 break; 1916 default: 1917 log(LOG_ERR, "Unknown format character %c in `%s'\n", format[i], format); 1918 } 1919 break; 1920 default: 1921 temp[n++] = format[i]; 1922 } 1923 } 1924 temp[n] = '\0'; 1925 return temp; 1926 } 1927 1928 /* 1929 * Dump a process' core. The main routine does some 1930 * policy checking, and creates the name of the coredump; 1931 * then it passes on a vnode and a size limit to the process-specific 1932 * coredump routine if there is one; if there _is not_ one, it returns 1933 * ENOSYS; otherwise it returns the error from the process-specific routine. 1934 * 1935 * XXX: VOP_GETATTR() here requires holding the vnode lock. 1936 */ 1937 1938 static int 1939 coredump(struct thread *td) 1940 { 1941 struct proc *p = td->td_proc; 1942 register struct vnode *vp; 1943 register struct ucred *cred = p->p_ucred; 1944 struct flock lf; 1945 struct nameidata nd; 1946 struct vattr vattr; 1947 int error, error1, flags; 1948 struct mount *mp; 1949 char *name; /* name of corefile */ 1950 off_t limit; 1951 1952 PROC_LOCK(p); 1953 _STOPEVENT(p, S_CORE, 0); 1954 1955 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) { 1956 PROC_UNLOCK(p); 1957 return (EFAULT); 1958 } 1959 1960 /* 1961 * Note that the bulk of limit checking is done after 1962 * the corefile is created. The exception is if the limit 1963 * for corefiles is 0, in which case we don't bother 1964 * creating the corefile at all. This layout means that 1965 * a corefile is truncated instead of not being created, 1966 * if it is larger than the limit. 1967 */ 1968 limit = p->p_rlimit[RLIMIT_CORE].rlim_cur; 1969 if (limit == 0) { 1970 PROC_UNLOCK(p); 1971 return 0; 1972 } 1973 PROC_UNLOCK(p); 1974 1975 restart: 1976 name = expand_name(p->p_comm, p->p_ucred->cr_uid, p->p_pid); 1977 if (name == NULL) 1978 return (EINVAL); 1979 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td); /* XXXKSE */ 1980 flags = O_CREAT | FWRITE | O_NOFOLLOW; 1981 error = vn_open(&nd, &flags, S_IRUSR | S_IWUSR); 1982 free(name, M_TEMP); 1983 if (error) 1984 return (error); 1985 NDFREE(&nd, NDF_ONLY_PNBUF); 1986 vp = nd.ni_vp; 1987 1988 VOP_UNLOCK(vp, 0, td); 1989 lf.l_whence = SEEK_SET; 1990 lf.l_start = 0; 1991 lf.l_len = 0; 1992 lf.l_type = F_WRLCK; 1993 error = VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK); 1994 if (error) 1995 goto out2; 1996 1997 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1998 lf.l_type = F_UNLCK; 1999 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2000 if ((error = vn_close(vp, FWRITE, cred, td)) != 0) 2001 return (error); 2002 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0) 2003 return (error); 2004 goto restart; 2005 } 2006 2007 /* Don't dump to non-regular files or files with links. */ 2008 if (vp->v_type != VREG || 2009 VOP_GETATTR(vp, &vattr, cred, td) || vattr.va_nlink != 1) { 2010 error = EFAULT; 2011 goto out1; 2012 } 2013 VATTR_NULL(&vattr); 2014 vattr.va_size = 0; 2015 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 2016 VOP_LEASE(vp, td, cred, LEASE_WRITE); 2017 VOP_SETATTR(vp, &vattr, cred, td); 2018 VOP_UNLOCK(vp, 0, td); 2019 PROC_LOCK(p); 2020 p->p_acflag |= ACORE; 2021 PROC_UNLOCK(p); 2022 2023 error = p->p_sysent->sv_coredump ? 2024 p->p_sysent->sv_coredump(td, vp, limit) : 2025 ENOSYS; 2026 2027 out1: 2028 lf.l_type = F_UNLCK; 2029 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK); 2030 vn_finished_write(mp); 2031 out2: 2032 error1 = vn_close(vp, FWRITE, cred, td); 2033 if (error == 0) 2034 error = error1; 2035 return (error); 2036 } 2037 2038 /* 2039 * Nonexistent system call-- signal process (may want to handle it). 2040 * Flag error in case process won't see signal immediately (blocked or ignored). 2041 */ 2042 #ifndef _SYS_SYSPROTO_H_ 2043 struct nosys_args { 2044 int dummy; 2045 }; 2046 #endif 2047 /* 2048 * MPSAFE 2049 */ 2050 /* ARGSUSED */ 2051 int 2052 nosys(td, args) 2053 struct thread *td; 2054 struct nosys_args *args; 2055 { 2056 struct proc *p = td->td_proc; 2057 2058 mtx_lock(&Giant); 2059 PROC_LOCK(p); 2060 psignal(p, SIGSYS); 2061 PROC_UNLOCK(p); 2062 mtx_unlock(&Giant); 2063 return (EINVAL); 2064 } 2065 2066 /* 2067 * Send a SIGIO or SIGURG signal to a process or process group using 2068 * stored credentials rather than those of the current process. 2069 */ 2070 void 2071 pgsigio(sigio, sig, checkctty) 2072 struct sigio *sigio; 2073 int sig, checkctty; 2074 { 2075 if (sigio == NULL) 2076 return; 2077 2078 if (sigio->sio_pgid > 0) { 2079 PROC_LOCK(sigio->sio_proc); 2080 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred)) 2081 psignal(sigio->sio_proc, sig); 2082 PROC_UNLOCK(sigio->sio_proc); 2083 } else if (sigio->sio_pgid < 0) { 2084 struct proc *p; 2085 2086 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) { 2087 PROC_LOCK(p); 2088 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) && 2089 (checkctty == 0 || (p->p_flag & P_CONTROLT))) 2090 psignal(p, sig); 2091 PROC_UNLOCK(p); 2092 } 2093 } 2094 } 2095 2096 static int 2097 filt_sigattach(struct knote *kn) 2098 { 2099 struct proc *p = curproc; 2100 2101 kn->kn_ptr.p_proc = p; 2102 kn->kn_flags |= EV_CLEAR; /* automatically set */ 2103 2104 PROC_LOCK(p); 2105 SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext); 2106 PROC_UNLOCK(p); 2107 2108 return (0); 2109 } 2110 2111 static void 2112 filt_sigdetach(struct knote *kn) 2113 { 2114 struct proc *p = kn->kn_ptr.p_proc; 2115 2116 PROC_LOCK(p); 2117 SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext); 2118 PROC_UNLOCK(p); 2119 } 2120 2121 /* 2122 * signal knotes are shared with proc knotes, so we apply a mask to 2123 * the hint in order to differentiate them from process hints. This 2124 * could be avoided by using a signal-specific knote list, but probably 2125 * isn't worth the trouble. 2126 */ 2127 static int 2128 filt_signal(struct knote *kn, long hint) 2129 { 2130 2131 if (hint & NOTE_SIGNAL) { 2132 hint &= ~NOTE_SIGNAL; 2133 2134 if (kn->kn_id == hint) 2135 kn->kn_data++; 2136 } 2137 return (kn->kn_data != 0); 2138 } 2139