FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_sig.c
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 #define SIGPROP /* include signal properties table */
46 #include <sys/param.h>
47 #include <sys/kernel.h>
48 #include <sys/sysproto.h>
49 #include <sys/signalvar.h>
50 #include <sys/resourcevar.h>
51 #include <sys/namei.h>
52 #include <sys/vnode.h>
53 #include <sys/proc.h>
54 #include <sys/pioctl.h>
55 #include <sys/systm.h>
56 #include <sys/acct.h>
57 #include <sys/fcntl.h>
58 #include <sys/wait.h>
59 #include <sys/ktrace.h>
60 #include <sys/syslog.h>
61 #include <sys/stat.h>
62 #include <sys/sysent.h>
63 #include <sys/sysctl.h>
64 #include <sys/malloc.h>
65
66 #include <machine/cpu.h>
67 #ifdef SMP
68 #include <machine/smp.h>
69 #endif
70
71 static int killpg1 __P((struct proc *cp, int signum, int pgid, int all));
72 static void setsigvec __P((struct proc *p, int signum, struct sigaction *sa));
73 static void stop __P((struct proc *));
74 static char *expand_name __P((const char *, uid_t, pid_t));
75 static int coredump __P((struct proc *));
76
77 static int kern_logsigexit = 1;
78 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW, &kern_logsigexit, 0, "");
79
80 /*
81 * Can process p, with pcred pc, send the signal signum to process q?
82 */
83 #define CANSIGNAL(p, pc, q, signum) \
84 ((pc)->pc_ucred->cr_uid == 0 || \
85 (pc)->p_ruid == (q)->p_cred->p_ruid || \
86 (pc)->pc_ucred->cr_uid == (q)->p_cred->p_ruid || \
87 (pc)->p_ruid == (q)->p_ucred->cr_uid || \
88 (pc)->pc_ucred->cr_uid == (q)->p_ucred->cr_uid || \
89 ((signum) == SIGCONT && (q)->p_session == (p)->p_session))
90
91 /*
92 * Policy -- Can real uid ruid with ucred uc send a signal to process q?
93 */
94 #define CANSIGIO(ruid, uc, q) \
95 ((uc)->cr_uid == 0 || \
96 (ruid) == (q)->p_cred->p_ruid || \
97 (uc)->cr_uid == (q)->p_cred->p_ruid || \
98 (ruid) == (q)->p_ucred->cr_uid || \
99 (uc)->cr_uid == (q)->p_ucred->cr_uid)
100
101 int sugid_coredump;
102 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW, &sugid_coredump, 0, "");
103
104 #ifndef _SYS_SYSPROTO_H_
105 struct sigaction_args {
106 int signum;
107 struct sigaction *nsa;
108 struct sigaction *osa;
109 };
110 #endif
111 /* ARGSUSED */
112 int
113 sigaction(p, uap)
114 struct proc *p;
115 register struct sigaction_args *uap;
116 {
117 struct sigaction vec;
118 register struct sigaction *sa;
119 register struct sigacts *ps = p->p_sigacts;
120 register int signum;
121 int bit, error;
122
123 signum = uap->signum;
124 if (signum <= 0 || signum >= NSIG)
125 return (EINVAL);
126 sa = &vec;
127 if (uap->osa) {
128 sa->sa_handler = ps->ps_sigact[signum];
129 sa->sa_mask = ps->ps_catchmask[signum];
130 bit = sigmask(signum);
131 sa->sa_flags = 0;
132 if ((ps->ps_sigonstack & bit) != 0)
133 sa->sa_flags |= SA_ONSTACK;
134 if ((ps->ps_sigintr & bit) == 0)
135 sa->sa_flags |= SA_RESTART;
136 if ((ps->ps_sigreset & bit) != 0)
137 sa->sa_flags |= SA_RESETHAND;
138 if ((ps->ps_signodefer & bit) != 0)
139 sa->sa_flags |= SA_NODEFER;
140 if (signum == SIGCHLD && p->p_procsig->ps_flag & P_NOCLDSTOP)
141 sa->sa_flags |= SA_NOCLDSTOP;
142 if (signum == SIGCHLD && p->p_procsig->ps_flag & P_NOCLDWAIT)
143 sa->sa_flags |= SA_NOCLDWAIT;
144 if ((error = copyout((caddr_t)sa, (caddr_t)uap->osa,
145 sizeof (vec))))
146 return (error);
147 }
148 if (uap->nsa) {
149 if ((error = copyin((caddr_t)uap->nsa, (caddr_t)sa,
150 sizeof (vec))))
151 return (error);
152 if ((signum == SIGKILL || signum == SIGSTOP) &&
153 sa->sa_handler != SIG_DFL)
154 return (EINVAL);
155 setsigvec(p, signum, sa);
156 }
157 return (0);
158 }
159
160 static void
161 setsigvec(p, signum, sa)
162 register struct proc *p;
163 int signum;
164 register struct sigaction *sa;
165 {
166 register struct sigacts *ps = p->p_sigacts;
167 register int bit;
168
169 bit = sigmask(signum);
170 /*
171 * Change setting atomically.
172 */
173 (void) splhigh();
174 ps->ps_sigact[signum] = sa->sa_handler;
175 ps->ps_catchmask[signum] = sa->sa_mask &~ sigcantmask;
176 if ((sa->sa_flags & SA_RESTART) == 0)
177 ps->ps_sigintr |= bit;
178 else
179 ps->ps_sigintr &= ~bit;
180 if (sa->sa_flags & SA_ONSTACK)
181 ps->ps_sigonstack |= bit;
182 else
183 ps->ps_sigonstack &= ~bit;
184 if (sa->sa_flags & SA_RESETHAND)
185 ps->ps_sigreset |= bit;
186 else
187 ps->ps_sigreset &= ~bit;
188 if (sa->sa_flags & SA_NODEFER)
189 ps->ps_signodefer |= bit;
190 else
191 ps->ps_signodefer &= ~bit;
192 #ifdef COMPAT_SUNOS
193 if (sa->sa_flags & SA_USERTRAMP)
194 ps->ps_usertramp |= bit;
195 else
196 ps->ps_usertramp &= ~bit;
197 #endif
198 if (signum == SIGCHLD) {
199 if (sa->sa_flags & SA_NOCLDSTOP)
200 p->p_procsig->ps_flag |= P_NOCLDSTOP;
201 else
202 p->p_procsig->ps_flag &= ~P_NOCLDSTOP;
203 if (sa->sa_flags & SA_NOCLDWAIT) {
204 /*
205 * Paranoia: since SA_NOCLDWAIT is implemented by
206 * reparenting the dying child to PID 1 (and
207 * trust it to reap the zombie), PID 1 itself is
208 * forbidden to set SA_NOCLDWAIT.
209 */
210 if (p->p_pid == 1)
211 p->p_procsig->ps_flag &= ~P_NOCLDWAIT;
212 else
213 p->p_procsig->ps_flag |= P_NOCLDWAIT;
214 } else
215 p->p_procsig->ps_flag &= ~P_NOCLDWAIT;
216 }
217 /*
218 * Set bit in p_sigignore for signals that are set to SIG_IGN,
219 * and for signals set to SIG_DFL where the default is to ignore.
220 * However, don't put SIGCONT in p_sigignore,
221 * as we have to restart the process.
222 */
223 if (sa->sa_handler == SIG_IGN ||
224 (sigprop[signum] & SA_IGNORE && sa->sa_handler == SIG_DFL)) {
225 p->p_siglist &= ~bit; /* never to be seen again */
226 if (signum != SIGCONT)
227 p->p_sigignore |= bit; /* easier in psignal */
228 p->p_sigcatch &= ~bit;
229 } else {
230 p->p_sigignore &= ~bit;
231 if (sa->sa_handler == SIG_DFL)
232 p->p_sigcatch &= ~bit;
233 else
234 p->p_sigcatch |= bit;
235 }
236 (void) spl0();
237 }
238
239 /*
240 * Initialize signal state for process 0;
241 * set to ignore signals that are ignored by default.
242 */
243 void
244 siginit(p)
245 struct proc *p;
246 {
247 register int i;
248
249 for (i = 0; i < NSIG; i++)
250 if (sigprop[i] & SA_IGNORE && i != SIGCONT)
251 p->p_sigignore |= sigmask(i);
252 }
253
254 /*
255 * Reset signals for an exec of the specified process.
256 */
257 void
258 execsigs(p)
259 register struct proc *p;
260 {
261 register struct sigacts *ps = p->p_sigacts;
262 register int nc, mask;
263
264 /*
265 * Reset caught signals. Held signals remain held
266 * through p_sigmask (unless they were caught,
267 * and are now ignored by default).
268 */
269 while (p->p_sigcatch) {
270 nc = ffs((long)p->p_sigcatch);
271 mask = sigmask(nc);
272 p->p_sigcatch &= ~mask;
273 if (sigprop[nc] & SA_IGNORE) {
274 if (nc != SIGCONT)
275 p->p_sigignore |= mask;
276 p->p_siglist &= ~mask;
277 }
278 ps->ps_sigact[nc] = SIG_DFL;
279 }
280 /*
281 * Reset stack state to the user stack.
282 * Clear set of signals caught on the signal stack.
283 */
284 ps->ps_sigstk.ss_flags = SS_DISABLE;
285 ps->ps_sigstk.ss_size = 0;
286 ps->ps_sigstk.ss_sp = 0;
287 ps->ps_flags = 0;
288 /*
289 * Reset no zombies if child dies flag as Solaris does.
290 */
291 p->p_procsig->ps_flag &= ~P_NOCLDWAIT;
292 }
293
294 /*
295 * Manipulate signal mask.
296 * Note that we receive new mask, not pointer,
297 * and return old mask as return value;
298 * the library stub does the rest.
299 */
300 #ifndef _SYS_SYSPROTO_H_
301 struct sigprocmask_args {
302 int how;
303 sigset_t mask;
304 };
305 #endif
306 int
307 sigprocmask(p, uap)
308 register struct proc *p;
309 struct sigprocmask_args *uap;
310 {
311 int error = 0;
312
313 p->p_retval[0] = p->p_sigmask;
314 (void) splhigh();
315
316 switch (uap->how) {
317 case SIG_BLOCK:
318 p->p_sigmask |= uap->mask &~ sigcantmask;
319 break;
320
321 case SIG_UNBLOCK:
322 p->p_sigmask &= ~uap->mask;
323 break;
324
325 case SIG_SETMASK:
326 p->p_sigmask = uap->mask &~ sigcantmask;
327 break;
328
329 default:
330 error = EINVAL;
331 break;
332 }
333 (void) spl0();
334 return (error);
335 }
336
337 #ifndef _SYS_SYSPROTO_H_
338 struct sigpending_args {
339 int dummy;
340 };
341 #endif
342 /* ARGSUSED */
343 int
344 sigpending(p, uap)
345 struct proc *p;
346 struct sigpending_args *uap;
347 {
348
349 p->p_retval[0] = p->p_siglist;
350 return (0);
351 }
352
353 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
354 /*
355 * Generalized interface signal handler, 4.3-compatible.
356 */
357 #ifndef _SYS_SYSPROTO_H_
358 struct osigvec_args {
359 int signum;
360 struct sigvec *nsv;
361 struct sigvec *osv;
362 };
363 #endif
364 /* ARGSUSED */
365 int
366 osigvec(p, uap)
367 struct proc *p;
368 register struct osigvec_args *uap;
369 {
370 struct sigvec vec;
371 register struct sigacts *ps = p->p_sigacts;
372 register struct sigvec *sv;
373 register int signum;
374 int bit, error;
375
376 signum = uap->signum;
377 if (signum <= 0 || signum >= NSIG)
378 return (EINVAL);
379 sv = &vec;
380 if (uap->osv) {
381 *(sig_t *)&sv->sv_handler = ps->ps_sigact[signum];
382 sv->sv_mask = ps->ps_catchmask[signum];
383 bit = sigmask(signum);
384 sv->sv_flags = 0;
385 if ((ps->ps_sigonstack & bit) != 0)
386 sv->sv_flags |= SV_ONSTACK;
387 if ((ps->ps_sigintr & bit) != 0)
388 sv->sv_flags |= SV_INTERRUPT;
389 if ((ps->ps_sigreset & bit) != 0)
390 sv->sv_flags |= SV_RESETHAND;
391 if ((ps->ps_signodefer & bit) != 0)
392 sv->sv_flags |= SV_NODEFER;
393 #ifndef COMPAT_SUNOS
394 if (signum == SIGCHLD && p->p_procsig->ps_flag & P_NOCLDSTOP)
395 sv->sv_flags |= SV_NOCLDSTOP;
396 #endif
397 if ((error = copyout((caddr_t)sv, (caddr_t)uap->osv,
398 sizeof (vec))))
399 return (error);
400 }
401 if (uap->nsv) {
402 if ((error = copyin((caddr_t)uap->nsv, (caddr_t)sv,
403 sizeof (vec))))
404 return (error);
405 if ((signum == SIGKILL || signum == SIGSTOP) &&
406 sv->sv_handler != SIG_DFL)
407 return (EINVAL);
408 #ifdef COMPAT_SUNOS
409 sv->sv_flags |= SA_USERTRAMP;
410 #endif
411 sv->sv_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
412 setsigvec(p, signum, (struct sigaction *)sv);
413 }
414 return (0);
415 }
416
417 #ifndef _SYS_SYSPROTO_H_
418 struct osigblock_args {
419 int mask;
420 };
421 #endif
422 int
423 osigblock(p, uap)
424 register struct proc *p;
425 struct osigblock_args *uap;
426 {
427
428 (void) splhigh();
429 p->p_retval[0] = p->p_sigmask;
430 p->p_sigmask |= uap->mask &~ sigcantmask;
431 (void) spl0();
432 return (0);
433 }
434
435 #ifndef _SYS_SYSPROTO_H_
436 struct osigsetmask_args {
437 int mask;
438 };
439 #endif
440 int
441 osigsetmask(p, uap)
442 struct proc *p;
443 struct osigsetmask_args *uap;
444 {
445
446 (void) splhigh();
447 p->p_retval[0] = p->p_sigmask;
448 p->p_sigmask = uap->mask &~ sigcantmask;
449 (void) spl0();
450 return (0);
451 }
452 #endif /* COMPAT_43 || COMPAT_SUNOS */
453
454 /*
455 * Suspend process until signal, providing mask to be set
456 * in the meantime. Note nonstandard calling convention:
457 * libc stub passes mask, not pointer, to save a copyin.
458 */
459 #ifndef _SYS_SYSPROTO_H_
460 struct sigsuspend_args {
461 sigset_t mask;
462 };
463 #endif
464 /* ARGSUSED */
465 int
466 sigsuspend(p, uap)
467 register struct proc *p;
468 struct sigsuspend_args *uap;
469 {
470 register struct sigacts *ps = p->p_sigacts;
471
472 /*
473 * When returning from sigpause, we want
474 * the old mask to be restored after the
475 * signal handler has finished. Thus, we
476 * save it here and mark the sigacts structure
477 * to indicate this.
478 */
479 p->p_oldsigmask = p->p_sigmask;
480 p->p_sigmask = uap->mask &~ sigcantmask;
481 while (tsleep((caddr_t) ps, PPAUSE|PCATCH, "pause", 0) == 0)
482 /* void */;
483 /* always return EINTR rather than ERESTART... */
484 return (EINTR);
485 }
486
487 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
488 #ifndef _SYS_SYSPROTO_H_
489 struct osigstack_args {
490 struct sigstack *nss;
491 struct sigstack *oss;
492 };
493 #endif
494 /* ARGSUSED */
495 int
496 osigstack(p, uap)
497 struct proc *p;
498 register struct osigstack_args *uap;
499 {
500 struct sigstack ss;
501 struct sigacts *psp;
502 int error = 0;
503
504 psp = p->p_sigacts;
505 ss.ss_sp = psp->ps_sigstk.ss_sp;
506 ss.ss_onstack = psp->ps_sigstk.ss_flags & SS_ONSTACK;
507 if (uap->oss && (error = copyout((caddr_t)&ss, (caddr_t)uap->oss,
508 sizeof (struct sigstack))))
509 return (error);
510 if (uap->nss && (error = copyin((caddr_t)uap->nss, (caddr_t)&ss,
511 sizeof (ss))) == 0) {
512 psp->ps_sigstk.ss_sp = ss.ss_sp;
513 psp->ps_sigstk.ss_size = 0;
514 psp->ps_sigstk.ss_flags |= ss.ss_onstack & SS_ONSTACK;
515 psp->ps_flags |= SAS_ALTSTACK;
516 }
517 return (error);
518 }
519 #endif /* COMPAT_43 || COMPAT_SUNOS */
520
521 #ifndef _SYS_SYSPROTO_H_
522 struct sigaltstack_args {
523 struct sigaltstack *nss;
524 struct sigaltstack *oss;
525 };
526 #endif
527 /* ARGSUSED */
528 int
529 sigaltstack(p, uap)
530 struct proc *p;
531 register struct sigaltstack_args *uap;
532 {
533 struct sigacts *psp;
534 struct sigaltstack ss;
535 int error;
536
537 psp = p->p_sigacts;
538 if ((psp->ps_flags & SAS_ALTSTACK) == 0)
539 psp->ps_sigstk.ss_flags |= SS_DISABLE;
540 if (uap->oss && (error = copyout((caddr_t)&psp->ps_sigstk,
541 (caddr_t)uap->oss, sizeof (struct sigaltstack))))
542 return (error);
543 if (uap->nss == 0)
544 return (0);
545 if ((error = copyin((caddr_t)uap->nss, (caddr_t)&ss, sizeof (ss))))
546 return (error);
547 if (ss.ss_flags & SS_DISABLE) {
548 if (psp->ps_sigstk.ss_flags & SS_ONSTACK)
549 return (EINVAL);
550 psp->ps_flags &= ~SAS_ALTSTACK;
551 psp->ps_sigstk.ss_flags = ss.ss_flags;
552 return (0);
553 }
554 if (ss.ss_size < MINSIGSTKSZ)
555 return (ENOMEM);
556 psp->ps_flags |= SAS_ALTSTACK;
557 psp->ps_sigstk= ss;
558 return (0);
559 }
560
561 /*
562 * Common code for kill process group/broadcast kill.
563 * cp is calling process.
564 */
565 int
566 killpg1(cp, signum, pgid, all)
567 register struct proc *cp;
568 int signum, pgid, all;
569 {
570 register struct proc *p;
571 register struct pcred *pc = cp->p_cred;
572 struct pgrp *pgrp;
573 int nfound = 0;
574
575 if (all)
576 /*
577 * broadcast
578 */
579 for (p = allproc.lh_first; p != 0; p = p->p_list.le_next) {
580 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
581 p == cp || !CANSIGNAL(cp, pc, p, signum))
582 continue;
583 nfound++;
584 if (signum)
585 psignal(p, signum);
586 }
587 else {
588 if (pgid == 0)
589 /*
590 * zero pgid means send to my process group.
591 */
592 pgrp = cp->p_pgrp;
593 else {
594 pgrp = pgfind(pgid);
595 if (pgrp == NULL)
596 return (ESRCH);
597 }
598 for (p = pgrp->pg_members.lh_first; p != 0;
599 p = p->p_pglist.le_next) {
600 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
601 p->p_stat == SZOMB ||
602 !CANSIGNAL(cp, pc, p, signum))
603 continue;
604 nfound++;
605 if (signum)
606 psignal(p, signum);
607 }
608 }
609 return (nfound ? 0 : ESRCH);
610 }
611
612 #ifndef _SYS_SYSPROTO_H_
613 struct kill_args {
614 int pid;
615 int signum;
616 };
617 #endif
618 /* ARGSUSED */
619 int
620 kill(cp, uap)
621 register struct proc *cp;
622 register struct kill_args *uap;
623 {
624 register struct proc *p;
625 register struct pcred *pc = cp->p_cred;
626
627 if ((u_int)uap->signum >= NSIG)
628 return (EINVAL);
629 if (uap->pid > 0) {
630 /* kill single process */
631 if ((p = pfind(uap->pid)) == NULL)
632 return (ESRCH);
633 if (!CANSIGNAL(cp, pc, p, uap->signum))
634 return (EPERM);
635 if (uap->signum)
636 psignal(p, uap->signum);
637 return (0);
638 }
639 switch (uap->pid) {
640 case -1: /* broadcast signal */
641 return (killpg1(cp, uap->signum, 0, 1));
642 case 0: /* signal own process group */
643 return (killpg1(cp, uap->signum, 0, 0));
644 default: /* negative explicit process group */
645 return (killpg1(cp, uap->signum, -uap->pid, 0));
646 }
647 /* NOTREACHED */
648 }
649
650 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
651 #ifndef _SYS_SYSPROTO_H_
652 struct okillpg_args {
653 int pgid;
654 int signum;
655 };
656 #endif
657 /* ARGSUSED */
658 int
659 okillpg(p, uap)
660 struct proc *p;
661 register struct okillpg_args *uap;
662 {
663
664 if ((u_int)uap->signum >= NSIG)
665 return (EINVAL);
666 return (killpg1(p, uap->signum, uap->pgid, 0));
667 }
668 #endif /* COMPAT_43 || COMPAT_SUNOS */
669
670 /*
671 * Send a signal to a process group.
672 */
673 void
674 gsignal(pgid, signum)
675 int pgid, signum;
676 {
677 struct pgrp *pgrp;
678
679 if (pgid && (pgrp = pgfind(pgid)))
680 pgsignal(pgrp, signum, 0);
681 }
682
683 /*
684 * Send a signal to a process group. If checktty is 1,
685 * limit to members which have a controlling terminal.
686 */
687 void
688 pgsignal(pgrp, signum, checkctty)
689 struct pgrp *pgrp;
690 int signum, checkctty;
691 {
692 register struct proc *p;
693
694 if (pgrp)
695 for (p = pgrp->pg_members.lh_first; p != 0;
696 p = p->p_pglist.le_next)
697 if (checkctty == 0 || p->p_flag & P_CONTROLT)
698 psignal(p, signum);
699 }
700
701 /*
702 * Send a signal caused by a trap to the current process.
703 * If it will be caught immediately, deliver it with correct code.
704 * Otherwise, post it normally.
705 */
706 void
707 trapsignal(p, signum, code)
708 struct proc *p;
709 register int signum;
710 u_long code;
711 {
712 register struct sigacts *ps = p->p_sigacts;
713 int mask;
714
715 mask = sigmask(signum);
716 if ((p->p_flag & P_TRACED) == 0 && (p->p_sigcatch & mask) != 0 &&
717 (p->p_sigmask & mask) == 0) {
718 p->p_stats->p_ru.ru_nsignals++;
719 #ifdef KTRACE
720 if (KTRPOINT(p, KTR_PSIG))
721 ktrpsig(p->p_tracep, signum, ps->ps_sigact[signum],
722 p->p_sigmask, code);
723 #endif
724 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[signum], signum,
725 p->p_sigmask, code);
726 p->p_sigmask |= ps->ps_catchmask[signum] |
727 (mask & ~ps->ps_signodefer);
728 if ((ps->ps_sigreset & mask) != 0) {
729 /*
730 * See setsigvec() for origin of this code.
731 */
732 p->p_sigcatch &= ~mask;
733 if (signum != SIGCONT && sigprop[signum] & SA_IGNORE)
734 p->p_sigignore |= mask;
735 ps->ps_sigact[signum] = SIG_DFL;
736 }
737 } else {
738 p->p_code = code; /* XXX for core dump/debugger */
739 p->p_sig = signum; /* XXX to verify code */
740 psignal(p, signum);
741 }
742 }
743
744 /*
745 * Send the signal to the process. If the signal has an action, the action
746 * is usually performed by the target process rather than the caller; we add
747 * the signal to the set of pending signals for the process.
748 *
749 * Exceptions:
750 * o When a stop signal is sent to a sleeping process that takes the
751 * default action, the process is stopped without awakening it.
752 * o SIGCONT restarts stopped processes (or puts them back to sleep)
753 * regardless of the signal action (eg, blocked or ignored).
754 *
755 * Other ignored signals are discarded immediately.
756 */
757 void
758 psignal(p, signum)
759 register struct proc *p;
760 register int signum;
761 {
762 register int s, prop;
763 register sig_t action;
764 int mask;
765
766 if ((u_int)signum >= NSIG || signum == 0) {
767 printf("psignal: signum %d\n", signum);
768 panic("psignal signal number");
769 }
770 mask = sigmask(signum);
771 prop = sigprop[signum];
772
773 /*
774 * If proc is traced, always give parent a chance;
775 * if signal event is tracked by procfs, give *that*
776 * a chance, as well.
777 */
778 if ((p->p_flag & P_TRACED) || (p->p_stops & S_SIG))
779 action = SIG_DFL;
780 else {
781 /*
782 * If the signal is being ignored,
783 * then we forget about it immediately.
784 * (Note: we don't set SIGCONT in p_sigignore,
785 * and if it is set to SIG_IGN,
786 * action will be SIG_DFL here.)
787 */
788 if ((p->p_sigignore & mask) || (p->p_flag & P_WEXIT))
789 return;
790 if (p->p_sigmask & mask)
791 action = SIG_HOLD;
792 else if (p->p_sigcatch & mask)
793 action = SIG_CATCH;
794 else
795 action = SIG_DFL;
796 }
797
798 if (p->p_nice > NZERO && action == SIG_DFL && (prop & SA_KILL) &&
799 (p->p_flag & P_TRACED) == 0)
800 p->p_nice = NZERO;
801
802 if (prop & SA_CONT)
803 p->p_siglist &= ~stopsigmask;
804
805 if (prop & SA_STOP) {
806 /*
807 * If sending a tty stop signal to a member of an orphaned
808 * process group, discard the signal here if the action
809 * is default; don't stop the process below if sleeping,
810 * and don't clear any pending SIGCONT.
811 */
812 if (prop & SA_TTYSTOP && p->p_pgrp->pg_jobc == 0 &&
813 action == SIG_DFL)
814 return;
815 p->p_siglist &= ~contsigmask;
816 }
817 p->p_siglist |= mask;
818
819 /*
820 * Defer further processing for signals which are held,
821 * except that stopped processes must be continued by SIGCONT.
822 */
823 if (action == SIG_HOLD && ((prop & SA_CONT) == 0 || p->p_stat != SSTOP))
824 return;
825 s = splhigh();
826 switch (p->p_stat) {
827
828 case SSLEEP:
829 /*
830 * If process is sleeping uninterruptibly
831 * we can't interrupt the sleep... the signal will
832 * be noticed when the process returns through
833 * trap() or syscall().
834 */
835 if ((p->p_flag & P_SINTR) == 0)
836 goto out;
837 /*
838 * Process is sleeping and traced... make it runnable
839 * so it can discover the signal in issignal() and stop
840 * for the parent.
841 */
842 if (p->p_flag & P_TRACED)
843 goto run;
844 /*
845 * If SIGCONT is default (or ignored) and process is
846 * asleep, we are finished; the process should not
847 * be awakened.
848 */
849 if ((prop & SA_CONT) && action == SIG_DFL) {
850 p->p_siglist &= ~mask;
851 goto out;
852 }
853 /*
854 * When a sleeping process receives a stop
855 * signal, process immediately if possible.
856 * All other (caught or default) signals
857 * cause the process to run.
858 */
859 if (prop & SA_STOP) {
860 if (action != SIG_DFL)
861 goto runfast;
862 /*
863 * If a child holding parent blocked,
864 * stopping could cause deadlock.
865 */
866 if (p->p_flag & P_PPWAIT)
867 goto out;
868 p->p_siglist &= ~mask;
869 p->p_xstat = signum;
870 if ((p->p_pptr->p_procsig->ps_flag & P_NOCLDSTOP) == 0)
871 psignal(p->p_pptr, SIGCHLD);
872 stop(p);
873 goto out;
874 } else
875 goto runfast;
876 /*NOTREACHED*/
877
878 case SSTOP:
879 /*
880 * If traced process is already stopped,
881 * then no further action is necessary.
882 */
883 if (p->p_flag & P_TRACED)
884 goto out;
885
886 /*
887 * Kill signal always sets processes running.
888 */
889 if (signum == SIGKILL)
890 goto runfast;
891
892 if (prop & SA_CONT) {
893 /*
894 * If SIGCONT is default (or ignored), we continue the
895 * process but don't leave the signal in p_siglist, as
896 * it has no further action. If SIGCONT is held, we
897 * continue the process and leave the signal in
898 * p_siglist. If the process catches SIGCONT, let it
899 * handle the signal itself. If it isn't waiting on
900 * an event, then it goes back to run state.
901 * Otherwise, process goes back to sleep state.
902 */
903 if (action == SIG_DFL)
904 p->p_siglist &= ~mask;
905 if (action == SIG_CATCH)
906 goto runfast;
907 if (p->p_wchan == 0)
908 goto run;
909 p->p_stat = SSLEEP;
910 goto out;
911 }
912
913 if (prop & SA_STOP) {
914 /*
915 * Already stopped, don't need to stop again.
916 * (If we did the shell could get confused.)
917 */
918 p->p_siglist &= ~mask; /* take it away */
919 goto out;
920 }
921
922 /*
923 * If process is sleeping interruptibly, then simulate a
924 * wakeup so that when it is continued, it will be made
925 * runnable and can look at the signal. But don't make
926 * the process runnable, leave it stopped.
927 */
928 if (p->p_wchan && p->p_flag & P_SINTR)
929 unsleep(p);
930 goto out;
931
932 default:
933 /*
934 * SRUN, SIDL, SZOMB do nothing with the signal,
935 * other than kicking ourselves if we are running.
936 * It will either never be noticed, or noticed very soon.
937 */
938 if (p == curproc)
939 signotify(p);
940 #ifdef SMP
941 else if (p->p_stat == SRUN)
942 forward_signal(p);
943 #endif
944 goto out;
945 }
946 /*NOTREACHED*/
947
948 runfast:
949 /*
950 * Raise priority to at least PUSER.
951 */
952 if (p->p_priority > PUSER)
953 p->p_priority = PUSER;
954 run:
955 setrunnable(p);
956 out:
957 splx(s);
958 }
959
960 /*
961 * If the current process has received a signal (should be caught or cause
962 * termination, should interrupt current syscall), return the signal number.
963 * Stop signals with default action are processed immediately, then cleared;
964 * they aren't returned. This is checked after each entry to the system for
965 * a syscall or trap (though this can usually be done without calling issignal
966 * by checking the pending signal masks in the CURSIG macro.) The normal call
967 * sequence is
968 *
969 * while (signum = CURSIG(curproc))
970 * postsig(signum);
971 */
972 int
973 issignal(p)
974 register struct proc *p;
975 {
976 register int signum, mask, prop;
977
978 for (;;) {
979 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
980
981 mask = p->p_siglist & ~p->p_sigmask;
982 if (p->p_flag & P_PPWAIT)
983 mask &= ~stopsigmask;
984 if (mask == 0) /* no signal to send */
985 return (0);
986 signum = ffs((long)mask);
987 mask = sigmask(signum);
988 prop = sigprop[signum];
989
990 STOPEVENT(p, S_SIG, signum);
991
992 /*
993 * We should see pending but ignored signals
994 * only if P_TRACED was on when they were posted.
995 */
996 if ((mask & p->p_sigignore) && (traced == 0)) {
997 p->p_siglist &= ~mask;
998 continue;
999 }
1000 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
1001 /*
1002 * If traced, always stop, and stay
1003 * stopped until released by the parent.
1004 */
1005 p->p_xstat = signum;
1006 psignal(p->p_pptr, SIGCHLD);
1007 do {
1008 stop(p);
1009 mi_switch();
1010 } while (!trace_req(p)
1011 && p->p_flag & P_TRACED);
1012
1013 /*
1014 * If the traced bit got turned off, go back up
1015 * to the top to rescan signals. This ensures
1016 * that p_sig* and ps_sigact are consistent.
1017 */
1018 if ((p->p_flag & P_TRACED) == 0)
1019 continue;
1020
1021 /*
1022 * If parent wants us to take the signal,
1023 * then it will leave it in p->p_xstat;
1024 * otherwise we just look for signals again.
1025 */
1026 p->p_siglist &= ~mask; /* clear the old signal */
1027 signum = p->p_xstat;
1028 if (signum == 0)
1029 continue;
1030
1031 /*
1032 * Put the new signal into p_siglist. If the
1033 * signal is being masked, look for other signals.
1034 */
1035 mask = sigmask(signum);
1036 p->p_siglist |= mask;
1037 if (p->p_sigmask & mask)
1038 continue;
1039 }
1040
1041 /*
1042 * Decide whether the signal should be returned.
1043 * Return the signal's number, or fall through
1044 * to clear it from the pending mask.
1045 */
1046 switch ((int)(intptr_t)p->p_sigacts->ps_sigact[signum]) {
1047
1048 case (int)SIG_DFL:
1049 /*
1050 * Don't take default actions on system processes.
1051 */
1052 if (p->p_pid <= 1) {
1053 #ifdef DIAGNOSTIC
1054 /*
1055 * Are you sure you want to ignore SIGSEGV
1056 * in init? XXX
1057 */
1058 printf("Process (pid %lu) got signal %d\n",
1059 (u_long)p->p_pid, signum);
1060 #endif
1061 break; /* == ignore */
1062 }
1063 /*
1064 * If there is a pending stop signal to process
1065 * with default action, stop here,
1066 * then clear the signal. However,
1067 * if process is member of an orphaned
1068 * process group, ignore tty stop signals.
1069 */
1070 if (prop & SA_STOP) {
1071 if (p->p_flag & P_TRACED ||
1072 (p->p_pgrp->pg_jobc == 0 &&
1073 prop & SA_TTYSTOP))
1074 break; /* == ignore */
1075 p->p_xstat = signum;
1076 stop(p);
1077 if ((p->p_pptr->p_procsig->ps_flag & P_NOCLDSTOP) == 0)
1078 psignal(p->p_pptr, SIGCHLD);
1079 mi_switch();
1080 break;
1081 } else if (prop & SA_IGNORE) {
1082 /*
1083 * Except for SIGCONT, shouldn't get here.
1084 * Default action is to ignore; drop it.
1085 */
1086 break; /* == ignore */
1087 } else
1088 return (signum);
1089 /*NOTREACHED*/
1090
1091 case (int)SIG_IGN:
1092 /*
1093 * Masking above should prevent us ever trying
1094 * to take action on an ignored signal other
1095 * than SIGCONT, unless process is traced.
1096 */
1097 if ((prop & SA_CONT) == 0 &&
1098 (p->p_flag & P_TRACED) == 0)
1099 printf("issignal\n");
1100 break; /* == ignore */
1101
1102 default:
1103 /*
1104 * This signal has an action, let
1105 * postsig() process it.
1106 */
1107 return (signum);
1108 }
1109 p->p_siglist &= ~mask; /* take the signal! */
1110 }
1111 /* NOTREACHED */
1112 }
1113
1114 /*
1115 * Put the argument process into the stopped state and notify the parent
1116 * via wakeup. Signals are handled elsewhere. The process must not be
1117 * on the run queue.
1118 */
1119 void
1120 stop(p)
1121 register struct proc *p;
1122 {
1123
1124 p->p_stat = SSTOP;
1125 p->p_flag &= ~P_WAITED;
1126 wakeup((caddr_t)p->p_pptr);
1127 }
1128
1129 /*
1130 * Take the action for the specified signal
1131 * from the current set of pending signals.
1132 */
1133 void
1134 postsig(signum)
1135 register int signum;
1136 {
1137 register struct proc *p = curproc;
1138 register struct sigacts *ps = p->p_sigacts;
1139 register sig_t action;
1140 int code, mask, returnmask;
1141
1142 KASSERT(signum != 0, ("postsig"));
1143
1144 mask = sigmask(signum);
1145 p->p_siglist &= ~mask;
1146 action = ps->ps_sigact[signum];
1147 #ifdef KTRACE
1148 if (KTRPOINT(p, KTR_PSIG))
1149 ktrpsig(p->p_tracep,
1150 signum, action, p->p_oldsigmask ?
1151 p->p_oldsigmask : p->p_sigmask, 0);
1152 #endif
1153 STOPEVENT(p, S_SIG, signum);
1154
1155 if (action == SIG_DFL) {
1156 /*
1157 * Default action, where the default is to kill
1158 * the process. (Other cases were ignored above.)
1159 */
1160 sigexit(p, signum);
1161 /* NOTREACHED */
1162 } else {
1163 /*
1164 * If we get here, the signal must be caught.
1165 */
1166 KASSERT(action != SIG_IGN && (p->p_sigmask & mask) == 0,
1167 ("postsig action"));
1168 /*
1169 * Set the new mask value and also defer further
1170 * occurences of this signal.
1171 *
1172 * Special case: user has done a sigpause. Here the
1173 * current mask is not of interest, but rather the
1174 * mask from before the sigpause is what we want
1175 * restored after the signal processing is completed.
1176 */
1177 (void) splhigh();
1178 if (p->p_oldsigmask) {
1179 returnmask = p->p_oldsigmask;
1180 p->p_oldsigmask = 0;
1181 } else
1182 returnmask = p->p_sigmask;
1183 p->p_sigmask |= ps->ps_catchmask[signum] |
1184 (mask & ~ps->ps_signodefer);
1185 if ((ps->ps_sigreset & mask) != 0) {
1186 /*
1187 * See setsigvec() for origin of this code.
1188 */
1189 p->p_sigcatch &= ~mask;
1190 if (signum != SIGCONT && sigprop[signum] & SA_IGNORE)
1191 p->p_sigignore |= mask;
1192 ps->ps_sigact[signum] = SIG_DFL;
1193 }
1194 (void) spl0();
1195 p->p_stats->p_ru.ru_nsignals++;
1196 if (p->p_sig != signum) {
1197 code = 0;
1198 } else {
1199 code = p->p_code;
1200 p->p_code = 0;
1201 p->p_sig = 0;
1202 }
1203 (*p->p_sysent->sv_sendsig)(action, signum, returnmask, code);
1204 }
1205 }
1206
1207 /*
1208 * Kill the current process for stated reason.
1209 */
1210 void
1211 killproc(p, why)
1212 struct proc *p;
1213 char *why;
1214 {
1215 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
1216 p->p_cred && p->p_ucred ? p->p_ucred->cr_uid : -1, why);
1217 psignal(p, SIGKILL);
1218 }
1219
1220 /*
1221 * Force the current process to exit with the specified signal, dumping core
1222 * if appropriate. We bypass the normal tests for masked and caught signals,
1223 * allowing unrecoverable failures to terminate the process without changing
1224 * signal state. Mark the accounting record with the signal termination.
1225 * If dumping core, save the signal number for the debugger. Calls exit and
1226 * does not return.
1227 */
1228 void
1229 sigexit(p, signum)
1230 register struct proc *p;
1231 int signum;
1232 {
1233
1234 p->p_acflag |= AXSIG;
1235 if (sigprop[signum] & SA_CORE) {
1236 p->p_sig = signum;
1237 /*
1238 * Log signals which would cause core dumps
1239 * (Log as LOG_INFO to appease those who don't want
1240 * these messages.)
1241 * XXX : Todo, as well as euid, write out ruid too
1242 */
1243 if (coredump(p) == 0)
1244 signum |= WCOREFLAG;
1245 if (kern_logsigexit)
1246 log(LOG_INFO,
1247 "pid %d (%s), uid %d: exited on signal %d%s\n",
1248 p->p_pid, p->p_comm,
1249 p->p_cred && p->p_ucred ? p->p_ucred->cr_uid : -1,
1250 signum &~ WCOREFLAG,
1251 signum & WCOREFLAG ? " (core dumped)" : "");
1252 }
1253 exit1(p, W_EXITCODE(0, signum));
1254 /* NOTREACHED */
1255 }
1256
1257 static char corefilename[MAXPATHLEN+1] = {"%N.core"};
1258 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
1259 sizeof(corefilename), "process corefile name format string");
1260
1261 /*
1262 * expand_name(name, uid, pid)
1263 * Expand the name described in corefilename, using name, uid, and pid.
1264 * corefilename is a printf-like string, with three format specifiers:
1265 * %N name of process ("name")
1266 * %P process id (pid)
1267 * %U user id (uid)
1268 * For example, "%N.core" is the default; they can be disabled completely
1269 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
1270 * This is controlled by the sysctl variable kern.corefile (see above).
1271 */
1272
1273 static char *
1274 expand_name(name, uid, pid)
1275 const char *name; uid_t uid; pid_t pid; {
1276 char *temp;
1277 char buf[11]; /* Buffer for pid/uid -- max 4B */
1278 int i, n;
1279 char *format = corefilename;
1280
1281 temp = malloc(MAXPATHLEN + 3, M_TEMP, M_NOWAIT);
1282 if (temp == NULL)
1283 return NULL;
1284 bzero(temp, MAXPATHLEN+3);
1285 for (i = 0, n = 0; i < MAXPATHLEN && format[i]; i++) {
1286 int l;
1287 switch (format[i]) {
1288 case '%': /* Format character */
1289 i++;
1290 switch (format[i]) {
1291 case '%':
1292 temp[n++] = '%';
1293 break;
1294 case 'N': /* process name */
1295 l = strlen(name);
1296 if ((n + l) > MAXPATHLEN) {
1297 log(LOG_ERR, "pid %d (%s), uid (%d): Path `%s%s' is too long\n",
1298 pid, name, uid, temp, name);
1299 free(temp, M_TEMP);
1300 return NULL;
1301 }
1302 memcpy(temp+n, name, l);
1303 n += l;
1304 break;
1305 case 'P': /* process id */
1306 sprintf(buf, "%u", pid);
1307 l = strlen(buf);
1308 if ((n + l) > MAXPATHLEN) {
1309 log(LOG_ERR, "pid %d (%s), uid (%d): Path `%s%s' is too long\n",
1310 pid, name, uid, temp, name);
1311 free(temp, M_TEMP);
1312 return NULL;
1313 }
1314 memcpy(temp+n, buf, l);
1315 n += l;
1316 break;
1317 case 'U': /* user id */
1318 sprintf(buf, "%u", uid);
1319 l = strlen(buf);
1320 if ((n + l) > MAXPATHLEN) {
1321 log(LOG_ERR, "pid %d (%s), uid (%d): Path `%s%s' is too long\n",
1322 pid, name, uid, temp, name);
1323 free(temp, M_TEMP);
1324 return NULL;
1325 }
1326 memcpy(temp+n, buf, l);
1327 n += l;
1328 break;
1329 default:
1330 log(LOG_ERR, "Unknown format character %c in `%s'\n", format[i], format);
1331 }
1332 break;
1333 default:
1334 temp[n++] = format[i];
1335 }
1336 }
1337 return temp;
1338 }
1339
1340 /*
1341 * Dump a process' core. The main routine does some
1342 * policy checking, and creates the name of the coredump;
1343 * then it passes on a vnode and a size limit to the process-specific
1344 * coredump routine if there is one; if there _is not_ one, it returns
1345 * ENOSYS; otherwise it returns the error from the process-specific routine.
1346 */
1347
1348 static int
1349 coredump(p)
1350 register struct proc *p;
1351 {
1352 register struct vnode *vp;
1353 register struct ucred *cred = p->p_cred->pc_ucred;
1354 struct nameidata nd;
1355 struct vattr vattr;
1356 int error, error1;
1357 char *name; /* name of corefile */
1358 off_t limit;
1359
1360 STOPEVENT(p, S_CORE, 0);
1361
1362 if ((sugid_coredump == 0) && p->p_flag & P_SUGID)
1363 return (EFAULT);
1364
1365 /*
1366 * Note that the bulk of limit checking is done after
1367 * the corefile is created. The exception is if the limit
1368 * for corefiles is 0, in which case we don't bother
1369 * creating the corefile at all. This layout means that
1370 * a corefile is truncated instead of not being created,
1371 * if it is larger than the limit.
1372 */
1373 limit = p->p_rlimit[RLIMIT_CORE].rlim_cur;
1374 if (limit == 0)
1375 return 0;
1376
1377 name = expand_name(p->p_comm, p->p_ucred->cr_uid, p->p_pid);
1378 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, p);
1379 error = vn_open(&nd, O_CREAT | FWRITE | O_NOFOLLOW, S_IRUSR | S_IWUSR);
1380 free(name, M_TEMP);
1381 if (error)
1382 return (error);
1383 vp = nd.ni_vp;
1384
1385 /* Don't dump to non-regular files or files with links. */
1386 if (vp->v_type != VREG ||
1387 VOP_GETATTR(vp, &vattr, cred, p) || vattr.va_nlink != 1) {
1388 error = EFAULT;
1389 goto out;
1390 }
1391 VATTR_NULL(&vattr);
1392 vattr.va_size = 0;
1393 VOP_LEASE(vp, p, cred, LEASE_WRITE);
1394 VOP_SETATTR(vp, &vattr, cred, p);
1395 p->p_acflag |= ACORE;
1396
1397 error = p->p_sysent->sv_coredump ?
1398 p->p_sysent->sv_coredump(p, vp, limit) :
1399 ENOSYS;
1400
1401 out:
1402 VOP_UNLOCK(vp, 0, p);
1403 error1 = vn_close(vp, FWRITE, cred, p);
1404 if (error == 0)
1405 error = error1;
1406 return (error);
1407 }
1408
1409 /*
1410 * Nonexistent system call-- signal process (may want to handle it).
1411 * Flag error in case process won't see signal immediately (blocked or ignored).
1412 */
1413 #ifndef _SYS_SYSPROTO_H_
1414 struct nosys_args {
1415 int dummy;
1416 };
1417 #endif
1418 /* ARGSUSED */
1419 int
1420 nosys(p, args)
1421 struct proc *p;
1422 struct nosys_args *args;
1423 {
1424
1425 psignal(p, SIGSYS);
1426 return (EINVAL);
1427 }
1428
1429 /*
1430 * Send a signal to a SIGIO or SIGURG to a process or process group using
1431 * stored credentials rather than those of the current process.
1432 */
1433 void
1434 pgsigio(sigio, signum, checkctty)
1435 struct sigio *sigio;
1436 int signum, checkctty;
1437 {
1438 if (sigio == NULL)
1439 return;
1440
1441 if (sigio->sio_pgid > 0) {
1442 if (CANSIGIO(sigio->sio_ruid, sigio->sio_ucred,
1443 sigio->sio_proc))
1444 psignal(sigio->sio_proc, signum);
1445 } else if (sigio->sio_pgid < 0) {
1446 struct proc *p;
1447
1448 for (p = sigio->sio_pgrp->pg_members.lh_first; p != NULL;
1449 p = p->p_pglist.le_next)
1450 if (CANSIGIO(sigio->sio_ruid, sigio->sio_ucred, p) &&
1451 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
1452 psignal(p, signum);
1453 }
1454 }
Cache object: 3f611ab3f75e18a4004e3e8282d69c67
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