Nuke huge mbuf macros stage 1/2: Remove massive inline mbuf macros to reduce
[dragonfly.git] / sys / kern / kern_sig.c
CommitLineData
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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: src/sys/kern/kern_sig.c,v 1.72.2.17 2003/05/16 16:34:34 obrien Exp $
235957ed 40 * $DragonFly: src/sys/kern/kern_sig.c,v 1.10 2003/07/12 17:54:35 dillon Exp $
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41 */
42
43#include "opt_compat.h"
44#include "opt_ktrace.h"
45
46#include <sys/param.h>
dadab5e9 47#include <sys/systm.h>
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48#include <sys/kernel.h>
49#include <sys/sysproto.h>
50#include <sys/signalvar.h>
51#include <sys/resourcevar.h>
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52#include <sys/vnode.h>
53#include <sys/event.h>
54#include <sys/proc.h>
dadab5e9 55#include <sys/namei.h>
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56#include <sys/pioctl.h>
57#include <sys/systm.h>
58#include <sys/acct.h>
59#include <sys/fcntl.h>
60#include <sys/wait.h>
61#include <sys/ktrace.h>
62#include <sys/syslog.h>
63#include <sys/stat.h>
64#include <sys/sysent.h>
65#include <sys/sysctl.h>
66#include <sys/malloc.h>
67#include <sys/unistd.h>
68
69
70#include <machine/ipl.h>
71#include <machine/cpu.h>
72#include <machine/smp.h>
73
74#define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
75
76static int coredump __P((struct proc *));
41c20dac 77static int do_sigaction __P((int sig, struct sigaction *act,
984263bc 78 struct sigaction *oact, int old));
41c20dac 79static int do_sigprocmask __P((int how, sigset_t *set,
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80 sigset_t *oset, int old));
81static char *expand_name __P((const char *, uid_t, pid_t));
41c20dac 82static int killpg1 __P((int sig, int pgid, int all));
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83static int sig_ffs __P((sigset_t *set));
84static int sigprop __P((int sig));
85static void stop __P((struct proc *));
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86#ifdef SMP
87static void signotify_remote(void *arg);
88#endif
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89
90static int filt_sigattach(struct knote *kn);
91static void filt_sigdetach(struct knote *kn);
92static int filt_signal(struct knote *kn, long hint);
93
94struct filterops sig_filtops =
95 { 0, filt_sigattach, filt_sigdetach, filt_signal };
96
97static int kern_logsigexit = 1;
98SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
99 &kern_logsigexit, 0,
100 "Log processes quitting on abnormal signals to syslog(3)");
101
102/*
103 * Can process p, with pcred pc, send the signal sig to process q?
104 */
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105#define CANSIGNAL(q, sig) \
106 (!p_trespass(curproc->p_ucred, (q)->p_ucred) || \
107 ((sig) == SIGCONT && (q)->p_session == curproc->p_session))
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108
109/*
110 * Policy -- Can real uid ruid with ucred uc send a signal to process q?
111 */
112#define CANSIGIO(ruid, uc, q) \
113 ((uc)->cr_uid == 0 || \
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114 (ruid) == (q)->p_ucred->cr_ruid || \
115 (uc)->cr_uid == (q)->p_ucred->cr_ruid || \
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116 (ruid) == (q)->p_ucred->cr_uid || \
117 (uc)->cr_uid == (q)->p_ucred->cr_uid)
118
119int sugid_coredump;
120SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
121 &sugid_coredump, 0, "Enable coredumping set user/group ID processes");
122
123static int do_coredump = 1;
124SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
125 &do_coredump, 0, "Enable/Disable coredumps");
126
127/*
128 * Signal properties and actions.
129 * The array below categorizes the signals and their default actions
130 * according to the following properties:
131 */
132#define SA_KILL 0x01 /* terminates process by default */
133#define SA_CORE 0x02 /* ditto and coredumps */
134#define SA_STOP 0x04 /* suspend process */
135#define SA_TTYSTOP 0x08 /* ditto, from tty */
136#define SA_IGNORE 0x10 /* ignore by default */
137#define SA_CONT 0x20 /* continue if suspended */
138#define SA_CANTMASK 0x40 /* non-maskable, catchable */
139
140static int sigproptbl[NSIG] = {
141 SA_KILL, /* SIGHUP */
142 SA_KILL, /* SIGINT */
143 SA_KILL|SA_CORE, /* SIGQUIT */
144 SA_KILL|SA_CORE, /* SIGILL */
145 SA_KILL|SA_CORE, /* SIGTRAP */
146 SA_KILL|SA_CORE, /* SIGABRT */
147 SA_KILL|SA_CORE, /* SIGEMT */
148 SA_KILL|SA_CORE, /* SIGFPE */
149 SA_KILL, /* SIGKILL */
150 SA_KILL|SA_CORE, /* SIGBUS */
151 SA_KILL|SA_CORE, /* SIGSEGV */
152 SA_KILL|SA_CORE, /* SIGSYS */
153 SA_KILL, /* SIGPIPE */
154 SA_KILL, /* SIGALRM */
155 SA_KILL, /* SIGTERM */
156 SA_IGNORE, /* SIGURG */
157 SA_STOP, /* SIGSTOP */
158 SA_STOP|SA_TTYSTOP, /* SIGTSTP */
159 SA_IGNORE|SA_CONT, /* SIGCONT */
160 SA_IGNORE, /* SIGCHLD */
161 SA_STOP|SA_TTYSTOP, /* SIGTTIN */
162 SA_STOP|SA_TTYSTOP, /* SIGTTOU */
163 SA_IGNORE, /* SIGIO */
164 SA_KILL, /* SIGXCPU */
165 SA_KILL, /* SIGXFSZ */
166 SA_KILL, /* SIGVTALRM */
167 SA_KILL, /* SIGPROF */
168 SA_IGNORE, /* SIGWINCH */
169 SA_IGNORE, /* SIGINFO */
170 SA_KILL, /* SIGUSR1 */
171 SA_KILL, /* SIGUSR2 */
172};
173
174static __inline int
175sigprop(int sig)
176{
177
178 if (sig > 0 && sig < NSIG)
179 return (sigproptbl[_SIG_IDX(sig)]);
180 return (0);
181}
182
183static __inline int
184sig_ffs(sigset_t *set)
185{
186 int i;
187
188 for (i = 0; i < _SIG_WORDS; i++)
189 if (set->__bits[i])
190 return (ffs(set->__bits[i]) + (i * 32));
191 return (0);
192}
193
194/*
195 * do_sigaction
196 * sigaction
197 * osigaction
198 */
199static int
41c20dac 200do_sigaction(int sig, struct sigaction *act, struct sigaction *oact, int old)
984263bc 201{
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202 struct proc *p = curproc;
203 struct sigacts *ps = p->p_sigacts;
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204
205 if (sig <= 0 || sig > _SIG_MAXSIG)
206 return (EINVAL);
207
208 if (oact) {
209 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
210 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
211 oact->sa_flags = 0;
212 if (SIGISMEMBER(ps->ps_sigonstack, sig))
213 oact->sa_flags |= SA_ONSTACK;
214 if (!SIGISMEMBER(ps->ps_sigintr, sig))
215 oact->sa_flags |= SA_RESTART;
216 if (SIGISMEMBER(ps->ps_sigreset, sig))
217 oact->sa_flags |= SA_RESETHAND;
218 if (SIGISMEMBER(ps->ps_signodefer, sig))
219 oact->sa_flags |= SA_NODEFER;
220 if (SIGISMEMBER(ps->ps_siginfo, sig))
221 oact->sa_flags |= SA_SIGINFO;
222 if (sig == SIGCHLD && p->p_procsig->ps_flag & PS_NOCLDSTOP)
223 oact->sa_flags |= SA_NOCLDSTOP;
224 if (sig == SIGCHLD && p->p_procsig->ps_flag & PS_NOCLDWAIT)
225 oact->sa_flags |= SA_NOCLDWAIT;
226 }
227 if (act) {
228 if ((sig == SIGKILL || sig == SIGSTOP) &&
229 act->sa_handler != SIG_DFL)
230 return (EINVAL);
231
232 /*
233 * Change setting atomically.
234 */
235 (void) splhigh();
236
237 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
238 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
239 if (act->sa_flags & SA_SIGINFO) {
240 ps->ps_sigact[_SIG_IDX(sig)] =
241 (__sighandler_t *)act->sa_sigaction;
242 SIGADDSET(ps->ps_siginfo, sig);
243 } else {
244 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
245 SIGDELSET(ps->ps_siginfo, sig);
246 }
247 if (!(act->sa_flags & SA_RESTART))
248 SIGADDSET(ps->ps_sigintr, sig);
249 else
250 SIGDELSET(ps->ps_sigintr, sig);
251 if (act->sa_flags & SA_ONSTACK)
252 SIGADDSET(ps->ps_sigonstack, sig);
253 else
254 SIGDELSET(ps->ps_sigonstack, sig);
255 if (act->sa_flags & SA_RESETHAND)
256 SIGADDSET(ps->ps_sigreset, sig);
257 else
258 SIGDELSET(ps->ps_sigreset, sig);
259 if (act->sa_flags & SA_NODEFER)
260 SIGADDSET(ps->ps_signodefer, sig);
261 else
262 SIGDELSET(ps->ps_signodefer, sig);
263#ifdef COMPAT_SUNOS
264 if (act->sa_flags & SA_USERTRAMP)
265 SIGADDSET(ps->ps_usertramp, sig);
266 else
267 SIGDELSET(ps->ps_usertramp, seg);
268#endif
269 if (sig == SIGCHLD) {
270 if (act->sa_flags & SA_NOCLDSTOP)
271 p->p_procsig->ps_flag |= PS_NOCLDSTOP;
272 else
273 p->p_procsig->ps_flag &= ~PS_NOCLDSTOP;
274 if (act->sa_flags & SA_NOCLDWAIT) {
275 /*
276 * Paranoia: since SA_NOCLDWAIT is implemented
277 * by reparenting the dying child to PID 1 (and
278 * trust it to reap the zombie), PID 1 itself
279 * is forbidden to set SA_NOCLDWAIT.
280 */
281 if (p->p_pid == 1)
282 p->p_procsig->ps_flag &= ~PS_NOCLDWAIT;
283 else
284 p->p_procsig->ps_flag |= PS_NOCLDWAIT;
285 } else
286 p->p_procsig->ps_flag &= ~PS_NOCLDWAIT;
287 }
288 /*
289 * Set bit in p_sigignore for signals that are set to SIG_IGN,
290 * and for signals set to SIG_DFL where the default is to
291 * ignore. However, don't put SIGCONT in p_sigignore, as we
292 * have to restart the process.
293 */
294 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
295 (sigprop(sig) & SA_IGNORE &&
296 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
297 /* never to be seen again */
298 SIGDELSET(p->p_siglist, sig);
299 if (sig != SIGCONT)
300 /* easier in psignal */
301 SIGADDSET(p->p_sigignore, sig);
302 SIGDELSET(p->p_sigcatch, sig);
303 } else {
304 SIGDELSET(p->p_sigignore, sig);
305 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
306 SIGDELSET(p->p_sigcatch, sig);
307 else
308 SIGADDSET(p->p_sigcatch, sig);
309 }
310 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
311 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL || !old)
312 SIGDELSET(ps->ps_osigset, sig);
313 else
314 SIGADDSET(ps->ps_osigset, sig);
315
316 (void) spl0();
317 }
318 return (0);
319}
320
321#ifndef _SYS_SYSPROTO_H_
322struct sigaction_args {
323 int sig;
324 struct sigaction *act;
325 struct sigaction *oact;
326};
327#endif
328/* ARGSUSED */
329int
41c20dac 330sigaction(struct sigaction_args *uap)
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331{
332 struct sigaction act, oact;
333 register struct sigaction *actp, *oactp;
334 int error;
335
336 actp = (uap->act != NULL) ? &act : NULL;
337 oactp = (uap->oact != NULL) ? &oact : NULL;
338 if (actp) {
339 error = copyin(uap->act, actp, sizeof(act));
340 if (error)
341 return (error);
342 }
41c20dac 343 error = do_sigaction(uap->sig, actp, oactp, 0);
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344 if (oactp && !error) {
345 error = copyout(oactp, uap->oact, sizeof(oact));
346 }
347 return (error);
348}
349
350#ifndef _SYS_SYSPROTO_H_
351struct osigaction_args {
352 int signum;
353 struct osigaction *nsa;
354 struct osigaction *osa;
355};
356#endif
357/* ARGSUSED */
358int
41c20dac 359osigaction(struct osigaction_args *uap)
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360{
361 struct osigaction sa;
362 struct sigaction nsa, osa;
363 register struct sigaction *nsap, *osap;
364 int error;
365
366 if (uap->signum <= 0 || uap->signum >= ONSIG)
367 return (EINVAL);
368 nsap = (uap->nsa != NULL) ? &nsa : NULL;
369 osap = (uap->osa != NULL) ? &osa : NULL;
370 if (nsap) {
371 error = copyin(uap->nsa, &sa, sizeof(sa));
372 if (error)
373 return (error);
374 nsap->sa_handler = sa.sa_handler;
375 nsap->sa_flags = sa.sa_flags;
376 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
377 }
41c20dac 378 error = do_sigaction(uap->signum, nsap, osap, 1);
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379 if (osap && !error) {
380 sa.sa_handler = osap->sa_handler;
381 sa.sa_flags = osap->sa_flags;
382 SIG2OSIG(osap->sa_mask, sa.sa_mask);
383 error = copyout(&sa, uap->osa, sizeof(sa));
384 }
385 return (error);
386}
387
388/*
389 * Initialize signal state for process 0;
390 * set to ignore signals that are ignored by default.
391 */
392void
393siginit(p)
394 struct proc *p;
395{
396 register int i;
397
398 for (i = 1; i <= NSIG; i++)
399 if (sigprop(i) & SA_IGNORE && i != SIGCONT)
400 SIGADDSET(p->p_sigignore, i);
401}
402
403/*
404 * Reset signals for an exec of the specified process.
405 */
406void
407execsigs(p)
408 register struct proc *p;
409{
410 register struct sigacts *ps = p->p_sigacts;
411 register int sig;
412
413 /*
414 * Reset caught signals. Held signals remain held
415 * through p_sigmask (unless they were caught,
416 * and are now ignored by default).
417 */
418 while (SIGNOTEMPTY(p->p_sigcatch)) {
419 sig = sig_ffs(&p->p_sigcatch);
420 SIGDELSET(p->p_sigcatch, sig);
421 if (sigprop(sig) & SA_IGNORE) {
422 if (sig != SIGCONT)
423 SIGADDSET(p->p_sigignore, sig);
424 SIGDELSET(p->p_siglist, sig);
425 }
426 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
427 }
428 /*
429 * Reset stack state to the user stack.
430 * Clear set of signals caught on the signal stack.
431 */
432 p->p_sigstk.ss_flags = SS_DISABLE;
433 p->p_sigstk.ss_size = 0;
434 p->p_sigstk.ss_sp = 0;
435 p->p_flag &= ~P_ALTSTACK;
436 /*
437 * Reset no zombies if child dies flag as Solaris does.
438 */
439 p->p_procsig->ps_flag &= ~PS_NOCLDWAIT;
440}
441
442/*
443 * do_sigprocmask() - MP SAFE ONLY IF p == curproc
444 *
445 * Manipulate signal mask. This routine is MP SAFE *ONLY* if
446 * p == curproc. Also remember that in order to remain MP SAFE
447 * no spl*() calls may be made.
448 */
449static int
41c20dac 450do_sigprocmask(int how, sigset_t *set, sigset_t *oset, int old)
984263bc 451{
41c20dac 452 struct proc *p = curproc;
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453 int error;
454
455 if (oset != NULL)
456 *oset = p->p_sigmask;
457
458 error = 0;
459 if (set != NULL) {
460 switch (how) {
461 case SIG_BLOCK:
462 SIG_CANTMASK(*set);
463 SIGSETOR(p->p_sigmask, *set);
464 break;
465 case SIG_UNBLOCK:
466 SIGSETNAND(p->p_sigmask, *set);
467 break;
468 case SIG_SETMASK:
469 SIG_CANTMASK(*set);
470 if (old)
471 SIGSETLO(p->p_sigmask, *set);
472 else
473 p->p_sigmask = *set;
474 break;
475 default:
476 error = EINVAL;
477 break;
478 }
479 }
480 return (error);
481}
482
483/*
484 * sigprocmask() - MP SAFE
485 */
486
487#ifndef _SYS_SYSPROTO_H_
488struct sigprocmask_args {
489 int how;
490 const sigset_t *set;
491 sigset_t *oset;
492};
493#endif
494int
41c20dac 495sigprocmask(struct sigprocmask_args *uap)
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496{
497 sigset_t set, oset;
498 sigset_t *setp, *osetp;
499 int error;
500
501 setp = (uap->set != NULL) ? &set : NULL;
502 osetp = (uap->oset != NULL) ? &oset : NULL;
503 if (setp) {
504 error = copyin(uap->set, setp, sizeof(set));
505 if (error)
506 return (error);
507 }
41c20dac 508 error = do_sigprocmask(uap->how, setp, osetp, 0);
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509 if (osetp && !error) {
510 error = copyout(osetp, uap->oset, sizeof(oset));
511 }
512 return (error);
513}
514
515/*
516 * osigprocmask() - MP SAFE
517 */
518
519#ifndef _SYS_SYSPROTO_H_
520struct osigprocmask_args {
521 int how;
522 osigset_t mask;
523};
524#endif
525int
41c20dac 526osigprocmask(struct osigprocmask_args *uap)
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527{
528 sigset_t set, oset;
529 int error;
530
531 OSIG2SIG(uap->mask, set);
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532 error = do_sigprocmask(uap->how, &set, &oset, 1);
533 SIG2OSIG(oset, curproc->p_retval[0]);
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534 return (error);
535}
536
537#ifndef _SYS_SYSPROTO_H_
538struct sigpending_args {
539 sigset_t *set;
540};
541#endif
542/* ARGSUSED */
543int
41c20dac 544sigpending(struct sigpending_args *uap)
984263bc 545{
41c20dac 546 struct proc *p = curproc;
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547
548 return (copyout(&p->p_siglist, uap->set, sizeof(sigset_t)));
549}
550
551#ifndef _SYS_SYSPROTO_H_
552struct osigpending_args {
553 int dummy;
554};
555#endif
556/* ARGSUSED */
557int
41c20dac 558osigpending(struct osigpending_args *uap)
984263bc 559{
41c20dac 560 struct proc *p = curproc;
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561
562 SIG2OSIG(p->p_siglist, p->p_retval[0]);
563 return (0);
564}
565
566#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
567/*
568 * Generalized interface signal handler, 4.3-compatible.
569 */
570#ifndef _SYS_SYSPROTO_H_
571struct osigvec_args {
572 int signum;
573 struct sigvec *nsv;
574 struct sigvec *osv;
575};
576#endif
577/* ARGSUSED */
578int
41c20dac 579osigvec(struct osigvec_args *uap)
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580{
581 struct sigvec vec;
582 struct sigaction nsa, osa;
583 register struct sigaction *nsap, *osap;
584 int error;
585
586 if (uap->signum <= 0 || uap->signum >= ONSIG)
587 return (EINVAL);
588 nsap = (uap->nsv != NULL) ? &nsa : NULL;
589 osap = (uap->osv != NULL) ? &osa : NULL;
590 if (nsap) {
591 error = copyin(uap->nsv, &vec, sizeof(vec));
592 if (error)
593 return (error);
594 nsap->sa_handler = vec.sv_handler;
595 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
596 nsap->sa_flags = vec.sv_flags;
597 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
598#ifdef COMPAT_SUNOS
599 nsap->sa_flags |= SA_USERTRAMP;
600#endif
601 }
41c20dac 602 error = do_sigaction(uap->signum, nsap, osap, 1);
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603 if (osap && !error) {
604 vec.sv_handler = osap->sa_handler;
605 SIG2OSIG(osap->sa_mask, vec.sv_mask);
606 vec.sv_flags = osap->sa_flags;
607 vec.sv_flags &= ~SA_NOCLDWAIT;
608 vec.sv_flags ^= SA_RESTART;
609#ifdef COMPAT_SUNOS
610 vec.sv_flags &= ~SA_NOCLDSTOP;
611#endif
612 error = copyout(&vec, uap->osv, sizeof(vec));
613 }
614 return (error);
615}
616
617#ifndef _SYS_SYSPROTO_H_
618struct osigblock_args {
619 int mask;
620};
621#endif
622int
41c20dac 623osigblock(struct osigblock_args *uap)
984263bc 624{
41c20dac 625 struct proc *p = curproc;
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626 sigset_t set;
627
628 OSIG2SIG(uap->mask, set);
629 SIG_CANTMASK(set);
630 (void) splhigh();
631 SIG2OSIG(p->p_sigmask, p->p_retval[0]);
632 SIGSETOR(p->p_sigmask, set);
633 (void) spl0();
634 return (0);
635}
636
637#ifndef _SYS_SYSPROTO_H_
638struct osigsetmask_args {
639 int mask;
640};
641#endif
642int
41c20dac 643osigsetmask(struct osigsetmask_args *uap)
984263bc 644{
41c20dac 645 struct proc *p = curproc;
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646 sigset_t set;
647
648 OSIG2SIG(uap->mask, set);
649 SIG_CANTMASK(set);
650 (void) splhigh();
651 SIG2OSIG(p->p_sigmask, p->p_retval[0]);
652 SIGSETLO(p->p_sigmask, set);
653 (void) spl0();
654 return (0);
655}
656#endif /* COMPAT_43 || COMPAT_SUNOS */
657
658/*
659 * Suspend process until signal, providing mask to be set
660 * in the meantime. Note nonstandard calling convention:
661 * libc stub passes mask, not pointer, to save a copyin.
662 */
663#ifndef _SYS_SYSPROTO_H_
664struct sigsuspend_args {
665 const sigset_t *sigmask;
666};
667#endif
668/* ARGSUSED */
669int
41c20dac 670sigsuspend(struct sigsuspend_args *uap)
984263bc 671{
41c20dac 672 struct proc *p = curproc;
984263bc 673 sigset_t mask;
41c20dac 674 struct sigacts *ps = p->p_sigacts;
984263bc
MD
675 int error;
676
677 error = copyin(uap->sigmask, &mask, sizeof(mask));
678 if (error)
679 return (error);
680
681 /*
682 * When returning from sigsuspend, we want
683 * the old mask to be restored after the
684 * signal handler has finished. Thus, we
685 * save it here and mark the sigacts structure
686 * to indicate this.
687 */
688 p->p_oldsigmask = p->p_sigmask;
689 p->p_flag |= P_OLDMASK;
690
691 SIG_CANTMASK(mask);
692 p->p_sigmask = mask;
693 while (tsleep((caddr_t) ps, PPAUSE|PCATCH, "pause", 0) == 0)
694 /* void */;
695 /* always return EINTR rather than ERESTART... */
696 return (EINTR);
697}
698
699#ifndef _SYS_SYSPROTO_H_
700struct osigsuspend_args {
701 osigset_t mask;
702};
703#endif
704/* ARGSUSED */
705int
41c20dac 706osigsuspend(struct osigsuspend_args *uap)
984263bc
MD
707{
708 sigset_t mask;
41c20dac
MD
709 struct proc *p = curproc;
710 struct sigacts *ps = p->p_sigacts;
984263bc
MD
711
712 p->p_oldsigmask = p->p_sigmask;
713 p->p_flag |= P_OLDMASK;
714 OSIG2SIG(uap->mask, mask);
715 SIG_CANTMASK(mask);
716 SIGSETLO(p->p_sigmask, mask);
717 while (tsleep((caddr_t) ps, PPAUSE|PCATCH, "opause", 0) == 0)
718 /* void */;
719 /* always return EINTR rather than ERESTART... */
720 return (EINTR);
721}
722
723#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
724#ifndef _SYS_SYSPROTO_H_
725struct osigstack_args {
726 struct sigstack *nss;
727 struct sigstack *oss;
728};
729#endif
730/* ARGSUSED */
731int
41c20dac 732osigstack(struct osigstack_args *uap)
984263bc 733{
41c20dac 734 struct proc *p = curproc;
984263bc
MD
735 struct sigstack ss;
736 int error = 0;
737
738 ss.ss_sp = p->p_sigstk.ss_sp;
739 ss.ss_onstack = p->p_sigstk.ss_flags & SS_ONSTACK;
740 if (uap->oss && (error = copyout(&ss, uap->oss,
741 sizeof(struct sigstack))))
742 return (error);
743 if (uap->nss && (error = copyin(uap->nss, &ss, sizeof(ss))) == 0) {
744 p->p_sigstk.ss_sp = ss.ss_sp;
745 p->p_sigstk.ss_size = 0;
746 p->p_sigstk.ss_flags |= ss.ss_onstack & SS_ONSTACK;
747 p->p_flag |= P_ALTSTACK;
748 }
749 return (error);
750}
751#endif /* COMPAT_43 || COMPAT_SUNOS */
752
753#ifndef _SYS_SYSPROTO_H_
754struct sigaltstack_args {
755 stack_t *ss;
756 stack_t *oss;
757};
758#endif
759/* ARGSUSED */
760int
41c20dac 761sigaltstack(struct sigaltstack_args *uap)
984263bc 762{
41c20dac 763 struct proc *p = curproc;
984263bc
MD
764 stack_t ss;
765 int error;
766
767 if ((p->p_flag & P_ALTSTACK) == 0)
768 p->p_sigstk.ss_flags |= SS_DISABLE;
769 if (uap->oss && (error = copyout(&p->p_sigstk, uap->oss,
770 sizeof(stack_t))))
771 return (error);
772 if (uap->ss == 0)
773 return (0);
774 if ((error = copyin(uap->ss, &ss, sizeof(ss))))
775 return (error);
776 if (ss.ss_flags & SS_DISABLE) {
777 if (p->p_sigstk.ss_flags & SS_ONSTACK)
778 return (EINVAL);
779 p->p_flag &= ~P_ALTSTACK;
780 p->p_sigstk.ss_flags = ss.ss_flags;
781 return (0);
782 }
783 if (ss.ss_size < p->p_sysent->sv_minsigstksz)
784 return (ENOMEM);
785 p->p_flag |= P_ALTSTACK;
786 p->p_sigstk = ss;
787 return (0);
788}
789
790/*
791 * Common code for kill process group/broadcast kill.
792 * cp is calling process.
793 */
794int
41c20dac 795killpg1(int sig, int pgid, int all)
984263bc 796{
41c20dac
MD
797 struct proc *cp = curproc;
798 struct proc *p;
984263bc
MD
799 struct pgrp *pgrp;
800 int nfound = 0;
801
802 if (all)
803 /*
804 * broadcast
805 */
806 LIST_FOREACH(p, &allproc, p_list) {
807 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
41c20dac 808 p == cp || !CANSIGNAL(p, sig))
984263bc
MD
809 continue;
810 nfound++;
811 if (sig)
812 psignal(p, sig);
813 }
814 else {
815 if (pgid == 0)
816 /*
817 * zero pgid means send to my process group.
818 */
819 pgrp = cp->p_pgrp;
820 else {
821 pgrp = pgfind(pgid);
822 if (pgrp == NULL)
823 return (ESRCH);
824 }
825 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
826 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
827 p->p_stat == SZOMB ||
41c20dac 828 !CANSIGNAL(p, sig))
984263bc
MD
829 continue;
830 nfound++;
831 if (sig)
832 psignal(p, sig);
833 }
834 }
835 return (nfound ? 0 : ESRCH);
836}
837
838#ifndef _SYS_SYSPROTO_H_
839struct kill_args {
840 int pid;
841 int signum;
842};
843#endif
844/* ARGSUSED */
845int
41c20dac 846kill(struct kill_args *uap)
984263bc 847{
41c20dac 848 struct proc *p;
984263bc
MD
849
850 if ((u_int)uap->signum > _SIG_MAXSIG)
851 return (EINVAL);
852 if (uap->pid > 0) {
853 /* kill single process */
854 if ((p = pfind(uap->pid)) == NULL)
855 return (ESRCH);
41c20dac 856 if (!CANSIGNAL(p, uap->signum))
984263bc
MD
857 return (EPERM);
858 if (uap->signum)
859 psignal(p, uap->signum);
860 return (0);
861 }
862 switch (uap->pid) {
863 case -1: /* broadcast signal */
41c20dac 864 return (killpg1(uap->signum, 0, 1));
984263bc 865 case 0: /* signal own process group */
41c20dac 866 return (killpg1(uap->signum, 0, 0));
984263bc 867 default: /* negative explicit process group */
41c20dac 868 return (killpg1(uap->signum, -uap->pid, 0));
984263bc
MD
869 }
870 /* NOTREACHED */
871}
872
873#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
874#ifndef _SYS_SYSPROTO_H_
875struct okillpg_args {
876 int pgid;
877 int signum;
878};
879#endif
880/* ARGSUSED */
881int
41c20dac 882okillpg(struct okillpg_args *uap)
984263bc 883{
984263bc
MD
884 if ((u_int)uap->signum > _SIG_MAXSIG)
885 return (EINVAL);
41c20dac 886 return (killpg1(uap->signum, uap->pgid, 0));
984263bc
MD
887}
888#endif /* COMPAT_43 || COMPAT_SUNOS */
889
890/*
891 * Send a signal to a process group.
892 */
893void
41c20dac 894gsignal(int pgid, int sig)
984263bc
MD
895{
896 struct pgrp *pgrp;
897
898 if (pgid && (pgrp = pgfind(pgid)))
899 pgsignal(pgrp, sig, 0);
900}
901
902/*
903 * Send a signal to a process group. If checktty is 1,
904 * limit to members which have a controlling terminal.
905 */
906void
907pgsignal(pgrp, sig, checkctty)
908 struct pgrp *pgrp;
909 int sig, checkctty;
910{
911 register struct proc *p;
912
913 if (pgrp)
914 LIST_FOREACH(p, &pgrp->pg_members, p_pglist)
915 if (checkctty == 0 || p->p_flag & P_CONTROLT)
916 psignal(p, sig);
917}
918
919/*
920 * Send a signal caused by a trap to the current process.
921 * If it will be caught immediately, deliver it with correct code.
922 * Otherwise, post it normally.
923 */
924void
925trapsignal(p, sig, code)
926 struct proc *p;
927 register int sig;
928 u_long code;
929{
dadab5e9 930 struct sigacts *ps = p->p_sigacts;
984263bc
MD
931
932 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(p->p_sigcatch, sig) &&
933 !SIGISMEMBER(p->p_sigmask, sig)) {
934 p->p_stats->p_ru.ru_nsignals++;
935#ifdef KTRACE
dadab5e9 936 if (KTRPOINT(p->p_thread, KTR_PSIG))
984263bc
MD
937 ktrpsig(p->p_tracep, sig, ps->ps_sigact[_SIG_IDX(sig)],
938 &p->p_sigmask, code);
939#endif
940 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)], sig,
941 &p->p_sigmask, code);
942 SIGSETOR(p->p_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
943 if (!SIGISMEMBER(ps->ps_signodefer, sig))
944 SIGADDSET(p->p_sigmask, sig);
945 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
946 /*
947 * See do_sigaction() for origin of this code.
948 */
949 SIGDELSET(p->p_sigcatch, sig);
950 if (sig != SIGCONT &&
951 sigprop(sig) & SA_IGNORE)
952 SIGADDSET(p->p_sigignore, sig);
953 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
954 }
955 } else {
956 p->p_code = code; /* XXX for core dump/debugger */
957 p->p_sig = sig; /* XXX to verify code */
958 psignal(p, sig);
959 }
960}
961
962/*
963 * Send the signal to the process. If the signal has an action, the action
964 * is usually performed by the target process rather than the caller; we add
965 * the signal to the set of pending signals for the process.
966 *
967 * Exceptions:
968 * o When a stop signal is sent to a sleeping process that takes the
969 * default action, the process is stopped without awakening it.
970 * o SIGCONT restarts stopped processes (or puts them back to sleep)
971 * regardless of the signal action (eg, blocked or ignored).
972 *
973 * Other ignored signals are discarded immediately.
974 */
cb973d15 975
984263bc
MD
976void
977psignal(p, sig)
978 register struct proc *p;
979 register int sig;
980{
cb973d15
MD
981 int s, prop;
982 sig_t action;
984263bc
MD
983
984 if (sig > _SIG_MAXSIG || sig <= 0) {
985 printf("psignal: signal %d\n", sig);
986 panic("psignal signal number");
987 }
988
989 s = splhigh();
990 KNOTE(&p->p_klist, NOTE_SIGNAL | sig);
991 splx(s);
992
993 prop = sigprop(sig);
994
995 /*
996 * If proc is traced, always give parent a chance;
997 * if signal event is tracked by procfs, give *that*
998 * a chance, as well.
999 */
1000 if ((p->p_flag & P_TRACED) || (p->p_stops & S_SIG))
1001 action = SIG_DFL;
1002 else {
1003 /*
1004 * If the signal is being ignored,
1005 * then we forget about it immediately.
1006 * (Note: we don't set SIGCONT in p_sigignore,
1007 * and if it is set to SIG_IGN,
1008 * action will be SIG_DFL here.)
1009 */
1010 if (SIGISMEMBER(p->p_sigignore, sig) || (p->p_flag & P_WEXIT))
1011 return;
1012 if (SIGISMEMBER(p->p_sigmask, sig))
1013 action = SIG_HOLD;
1014 else if (SIGISMEMBER(p->p_sigcatch, sig))
1015 action = SIG_CATCH;
1016 else
1017 action = SIG_DFL;
1018 }
1019
1020 if (p->p_nice > NZERO && action == SIG_DFL && (prop & SA_KILL) &&
1021 (p->p_flag & P_TRACED) == 0)
1022 p->p_nice = NZERO;
1023
1024 if (prop & SA_CONT)
1025 SIG_STOPSIGMASK(p->p_siglist);
1026
1027 if (prop & SA_STOP) {
1028 /*
1029 * If sending a tty stop signal to a member of an orphaned
1030 * process group, discard the signal here if the action
1031 * is default; don't stop the process below if sleeping,
1032 * and don't clear any pending SIGCONT.
1033 */
1034 if (prop & SA_TTYSTOP && p->p_pgrp->pg_jobc == 0 &&
1035 action == SIG_DFL)
1036 return;
1037 SIG_CONTSIGMASK(p->p_siglist);
1038 }
1039 SIGADDSET(p->p_siglist, sig);
1040
1041 /*
1042 * Defer further processing for signals which are held,
1043 * except that stopped processes must be continued by SIGCONT.
1044 */
1045 if (action == SIG_HOLD && (!(prop & SA_CONT) || p->p_stat != SSTOP))
1046 return;
1047 s = splhigh();
1048 switch (p->p_stat) {
1049
1050 case SSLEEP:
1051 /*
1052 * If process is sleeping uninterruptibly
1053 * we can't interrupt the sleep... the signal will
1054 * be noticed when the process returns through
1055 * trap() or syscall().
1056 */
1057 if ((p->p_flag & P_SINTR) == 0)
1058 goto out;
1059 /*
1060 * Process is sleeping and traced... make it runnable
1061 * so it can discover the signal in issignal() and stop
1062 * for the parent.
1063 */
1064 if (p->p_flag & P_TRACED)
1065 goto run;
1066 /*
1067 * If SIGCONT is default (or ignored) and process is
1068 * asleep, we are finished; the process should not
1069 * be awakened.
1070 */
1071 if ((prop & SA_CONT) && action == SIG_DFL) {
1072 SIGDELSET(p->p_siglist, sig);
1073 goto out;
1074 }
1075 /*
1076 * When a sleeping process receives a stop
1077 * signal, process immediately if possible.
1078 * All other (caught or default) signals
1079 * cause the process to run.
1080 */
1081 if (prop & SA_STOP) {
1082 if (action != SIG_DFL)
26a0694b 1083 goto run;
984263bc
MD
1084 /*
1085 * If a child holding parent blocked,
1086 * stopping could cause deadlock.
1087 */
1088 if (p->p_flag & P_PPWAIT)
1089 goto out;
1090 SIGDELSET(p->p_siglist, sig);
1091 p->p_xstat = sig;
1092 if ((p->p_pptr->p_procsig->ps_flag & PS_NOCLDSTOP) == 0)
1093 psignal(p->p_pptr, SIGCHLD);
1094 stop(p);
1095 goto out;
1096 } else
26a0694b 1097 goto run;
984263bc
MD
1098 /*NOTREACHED*/
1099
1100 case SSTOP:
1101 /*
1102 * If traced process is already stopped,
1103 * then no further action is necessary.
1104 */
1105 if (p->p_flag & P_TRACED)
1106 goto out;
1107
1108 /*
1109 * Kill signal always sets processes running.
1110 */
1111 if (sig == SIGKILL)
26a0694b 1112 goto run;
984263bc
MD
1113
1114 if (prop & SA_CONT) {
1115 /*
1116 * If SIGCONT is default (or ignored), we continue the
1117 * process but don't leave the signal in p_siglist, as
1118 * it has no further action. If SIGCONT is held, we
1119 * continue the process and leave the signal in
1120 * p_siglist. If the process catches SIGCONT, let it
1121 * handle the signal itself. If it isn't waiting on
1122 * an event, then it goes back to run state.
1123 * Otherwise, process goes back to sleep state.
1124 */
1125 if (action == SIG_DFL)
1126 SIGDELSET(p->p_siglist, sig);
1127 if (action == SIG_CATCH)
26a0694b 1128 goto run;
984263bc
MD
1129 if (p->p_wchan == 0)
1130 goto run;
26a0694b 1131 clrrunnable(p, SSLEEP);
984263bc
MD
1132 goto out;
1133 }
1134
1135 if (prop & SA_STOP) {
1136 /*
1137 * Already stopped, don't need to stop again.
1138 * (If we did the shell could get confused.)
1139 */
1140 SIGDELSET(p->p_siglist, sig);
1141 goto out;
1142 }
1143
1144 /*
1145 * If process is sleeping interruptibly, then simulate a
1146 * wakeup so that when it is continued, it will be made
1147 * runnable and can look at the signal. But don't make
1148 * the process runnable, leave it stopped.
1149 */
92e4c1e5 1150 if (p->p_wchan && (p->p_flag & P_SINTR))
0cfcada1 1151 unsleep(p->p_thread);
984263bc
MD
1152 goto out;
1153
1154 default:
1155 /*
1156 * SRUN, SIDL, SZOMB do nothing with the signal,
1157 * other than kicking ourselves if we are running.
1158 * It will either never be noticed, or noticed very soon.
cb973d15
MD
1159 *
1160 * For SMP we may have to forward the request to another cpu.
1161 * YYY the MP lock prevents the target process from moving
1162 * to another cpu, see kern/kern_switch.c
984263bc 1163 */
984263bc 1164#ifdef SMP
cb973d15 1165 if (p == lwkt_preempted_proc()) {
235957ed 1166 signotify();
cb973d15
MD
1167 } else {
1168 int cpuid = p->p_thread->td_cpu;
1169 if (cpuid != mycpu->gd_cpuid)
1170 lwkt_send_ipiq(cpuid, signotify_remote, p);
1171 }
1172#else
1173 if (p == lwkt_preempted_proc())
235957ed 1174 signotify();
984263bc
MD
1175#endif
1176 goto out;
1177 }
1178 /*NOTREACHED*/
984263bc
MD
1179run:
1180 setrunnable(p);
1181out:
1182 splx(s);
1183}
1184
cb973d15
MD
1185#ifdef SMP
1186
1187/*
1188 * This function is called via an IPI. We will be in a critical section but
1189 * the MP lock will NOT be held. Also note that by the time the ipi message
1190 * gets to us the process 'p' (arg) may no longer be scheduled or even valid.
1191 */
1192static void
1193signotify_remote(void *arg)
1194{
1195 struct proc *p = arg;
1196 if (p == lwkt_preempted_proc())
235957ed 1197 signotify();
cb973d15
MD
1198}
1199
1200#endif
1201
984263bc
MD
1202/*
1203 * If the current process has received a signal (should be caught or cause
1204 * termination, should interrupt current syscall), return the signal number.
1205 * Stop signals with default action are processed immediately, then cleared;
1206 * they aren't returned. This is checked after each entry to the system for
1207 * a syscall or trap (though this can usually be done without calling issignal
1208 * by checking the pending signal masks in the CURSIG macro.) The normal call
1209 * sequence is
1210 *
1211 * while (sig = CURSIG(curproc))
1212 * postsig(sig);
1213 */
1214int
1215issignal(p)
1216 register struct proc *p;
1217{
1218 sigset_t mask;
1219 register int sig, prop;
1220
1221 for (;;) {
1222 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
1223
1224 mask = p->p_siglist;
1225 SIGSETNAND(mask, p->p_sigmask);
1226 if (p->p_flag & P_PPWAIT)
1227 SIG_STOPSIGMASK(mask);
1228 if (!SIGNOTEMPTY(mask)) /* no signal to send */
1229 return (0);
1230 sig = sig_ffs(&mask);
1231
1232 STOPEVENT(p, S_SIG, sig);
1233
1234 /*
1235 * We should see pending but ignored signals
1236 * only if P_TRACED was on when they were posted.
1237 */
1238 if (SIGISMEMBER(p->p_sigignore, sig) && (traced == 0)) {
1239 SIGDELSET(p->p_siglist, sig);
1240 continue;
1241 }
1242 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
1243 /*
1244 * If traced, always stop, and stay
1245 * stopped until released by the parent.
1246 */
1247 p->p_xstat = sig;
1248 psignal(p->p_pptr, SIGCHLD);
1249 do {
1250 stop(p);
1251 mi_switch();
26a0694b 1252 } while (!trace_req(p) && p->p_flag & P_TRACED);
984263bc
MD
1253
1254 /*
1255 * If parent wants us to take the signal,
1256 * then it will leave it in p->p_xstat;
1257 * otherwise we just look for signals again.
1258 */
1259 SIGDELSET(p->p_siglist, sig); /* clear old signal */
1260 sig = p->p_xstat;
1261 if (sig == 0)
1262 continue;
1263
1264 /*
1265 * Put the new signal into p_siglist. If the
1266 * signal is being masked, look for other signals.
1267 */
1268 SIGADDSET(p->p_siglist, sig);
1269 if (SIGISMEMBER(p->p_sigmask, sig))
1270 continue;
1271
1272 /*
1273 * If the traced bit got turned off, go back up
1274 * to the top to rescan signals. This ensures
1275 * that p_sig* and ps_sigact are consistent.
1276 */
1277 if ((p->p_flag & P_TRACED) == 0)
1278 continue;
1279 }
1280
1281 prop = sigprop(sig);
1282
1283 /*
1284 * Decide whether the signal should be returned.
1285 * Return the signal's number, or fall through
1286 * to clear it from the pending mask.
1287 */
1288 switch ((int)(intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
1289
1290 case (int)SIG_DFL:
1291 /*
1292 * Don't take default actions on system processes.
1293 */
1294 if (p->p_pid <= 1) {
1295#ifdef DIAGNOSTIC
1296 /*
1297 * Are you sure you want to ignore SIGSEGV
1298 * in init? XXX
1299 */
1300 printf("Process (pid %lu) got signal %d\n",
1301 (u_long)p->p_pid, sig);
1302#endif
1303 break; /* == ignore */
1304 }
1305 /*
1306 * If there is a pending stop signal to process
1307 * with default action, stop here,
1308 * then clear the signal. However,
1309 * if process is member of an orphaned
1310 * process group, ignore tty stop signals.
1311 */
1312 if (prop & SA_STOP) {
1313 if (p->p_flag & P_TRACED ||
1314 (p->p_pgrp->pg_jobc == 0 &&
1315 prop & SA_TTYSTOP))
1316 break; /* == ignore */
1317 p->p_xstat = sig;
1318 stop(p);
1319 if ((p->p_pptr->p_procsig->ps_flag & PS_NOCLDSTOP) == 0)
1320 psignal(p->p_pptr, SIGCHLD);
1321 mi_switch();
1322 break;
1323 } else if (prop & SA_IGNORE) {
1324 /*
1325 * Except for SIGCONT, shouldn't get here.
1326 * Default action is to ignore; drop it.
1327 */
1328 break; /* == ignore */
1329 } else
1330 return (sig);
1331 /*NOTREACHED*/
1332
1333 case (int)SIG_IGN:
1334 /*
1335 * Masking above should prevent us ever trying
1336 * to take action on an ignored signal other
1337 * than SIGCONT, unless process is traced.
1338 */
1339 if ((prop & SA_CONT) == 0 &&
1340 (p->p_flag & P_TRACED) == 0)
1341 printf("issignal\n");
1342 break; /* == ignore */
1343
1344 default:
1345 /*
1346 * This signal has an action, let
1347 * postsig() process it.
1348 */
1349 return (sig);
1350 }
1351 SIGDELSET(p->p_siglist, sig); /* take the signal! */
1352 }
1353 /* NOTREACHED */
1354}
1355
1356/*
1357 * Put the argument process into the stopped state and notify the parent
1358 * via wakeup. Signals are handled elsewhere. The process must not be
1359 * on the run queue.
1360 */
1361void
1362stop(p)
1363 register struct proc *p;
1364{
1365
1366 p->p_stat = SSTOP;
1367 p->p_flag &= ~P_WAITED;
1368 wakeup((caddr_t)p->p_pptr);
1369}
1370
1371/*
1372 * Take the action for the specified signal
1373 * from the current set of pending signals.
1374 */
1375void
1376postsig(sig)
1377 register int sig;
1378{
41c20dac 1379 struct proc *p = curproc;
984263bc
MD
1380 struct sigacts *ps = p->p_sigacts;
1381 sig_t action;
1382 sigset_t returnmask;
1383 int code;
1384
1385 KASSERT(sig != 0, ("postsig"));
1386
1387 SIGDELSET(p->p_siglist, sig);
1388 action = ps->ps_sigact[_SIG_IDX(sig)];
1389#ifdef KTRACE
dadab5e9 1390 if (KTRPOINT(p->p_thread, KTR_PSIG))
984263bc
MD
1391 ktrpsig(p->p_tracep, sig, action, p->p_flag & P_OLDMASK ?
1392 &p->p_oldsigmask : &p->p_sigmask, 0);
1393#endif
1394 STOPEVENT(p, S_SIG, sig);
1395
1396 if (action == SIG_DFL) {
1397 /*
1398 * Default action, where the default is to kill
1399 * the process. (Other cases were ignored above.)
1400 */
1401 sigexit(p, sig);
1402 /* NOTREACHED */
1403 } else {
1404 /*
1405 * If we get here, the signal must be caught.
1406 */
1407 KASSERT(action != SIG_IGN && !SIGISMEMBER(p->p_sigmask, sig),
1408 ("postsig action"));
1409 /*
1410 * Set the new mask value and also defer further
1411 * occurrences of this signal.
1412 *
1413 * Special case: user has done a sigsuspend. Here the
1414 * current mask is not of interest, but rather the
1415 * mask from before the sigsuspend is what we want
1416 * restored after the signal processing is completed.
1417 */
1418 (void) splhigh();
1419 if (p->p_flag & P_OLDMASK) {
1420 returnmask = p->p_oldsigmask;
1421 p->p_flag &= ~P_OLDMASK;
1422 } else
1423 returnmask = p->p_sigmask;
1424
1425 SIGSETOR(p->p_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
1426 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1427 SIGADDSET(p->p_sigmask, sig);
1428
1429 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1430 /*
1431 * See do_sigaction() for origin of this code.
1432 */
1433 SIGDELSET(p->p_sigcatch, sig);
1434 if (sig != SIGCONT &&
1435 sigprop(sig) & SA_IGNORE)
1436 SIGADDSET(p->p_sigignore, sig);
1437 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1438 }
1439 (void) spl0();
1440 p->p_stats->p_ru.ru_nsignals++;
1441 if (p->p_sig != sig) {
1442 code = 0;
1443 } else {
1444 code = p->p_code;
1445 p->p_code = 0;
1446 p->p_sig = 0;
1447 }
1448 (*p->p_sysent->sv_sendsig)(action, sig, &returnmask, code);
1449 }
1450}
1451
1452/*
1453 * Kill the current process for stated reason.
1454 */
1455void
1456killproc(p, why)
1457 struct proc *p;
1458 char *why;
1459{
1460 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
41c20dac 1461 p->p_ucred ? p->p_ucred->cr_uid : -1, why);
984263bc
MD
1462 psignal(p, SIGKILL);
1463}
1464
1465/*
1466 * Force the current process to exit with the specified signal, dumping core
1467 * if appropriate. We bypass the normal tests for masked and caught signals,
1468 * allowing unrecoverable failures to terminate the process without changing
1469 * signal state. Mark the accounting record with the signal termination.
1470 * If dumping core, save the signal number for the debugger. Calls exit and
1471 * does not return.
1472 */
1473void
41c20dac 1474sigexit(struct proc *p, int sig)
984263bc 1475{
984263bc
MD
1476 p->p_acflag |= AXSIG;
1477 if (sigprop(sig) & SA_CORE) {
1478 p->p_sig = sig;
1479 /*
1480 * Log signals which would cause core dumps
1481 * (Log as LOG_INFO to appease those who don't want
1482 * these messages.)
1483 * XXX : Todo, as well as euid, write out ruid too
1484 */
1485 if (coredump(p) == 0)
1486 sig |= WCOREFLAG;
1487 if (kern_logsigexit)
1488 log(LOG_INFO,
1489 "pid %d (%s), uid %d: exited on signal %d%s\n",
1490 p->p_pid, p->p_comm,
41c20dac 1491 p->p_ucred ? p->p_ucred->cr_uid : -1,
984263bc
MD
1492 sig &~ WCOREFLAG,
1493 sig & WCOREFLAG ? " (core dumped)" : "");
1494 }
41c20dac 1495 exit1(W_EXITCODE(0, sig));
984263bc
MD
1496 /* NOTREACHED */
1497}
1498
1499static char corefilename[MAXPATHLEN+1] = {"%N.core"};
1500SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
1501 sizeof(corefilename), "process corefile name format string");
1502
1503/*
1504 * expand_name(name, uid, pid)
1505 * Expand the name described in corefilename, using name, uid, and pid.
1506 * corefilename is a printf-like string, with three format specifiers:
1507 * %N name of process ("name")
1508 * %P process id (pid)
1509 * %U user id (uid)
1510 * For example, "%N.core" is the default; they can be disabled completely
1511 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
1512 * This is controlled by the sysctl variable kern.corefile (see above).
1513 */
1514
1515static char *
1516expand_name(name, uid, pid)
1517const char *name; uid_t uid; pid_t pid; {
1518 char *temp;
1519 char buf[11]; /* Buffer for pid/uid -- max 4B */
1520 int i, n;
1521 char *format = corefilename;
1522 size_t namelen;
1523
1524 temp = malloc(MAXPATHLEN + 1, M_TEMP, M_NOWAIT);
1525 if (temp == NULL)
1526 return NULL;
1527 namelen = strlen(name);
1528 for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) {
1529 int l;
1530 switch (format[i]) {
1531 case '%': /* Format character */
1532 i++;
1533 switch (format[i]) {
1534 case '%':
1535 temp[n++] = '%';
1536 break;
1537 case 'N': /* process name */
1538 if ((n + namelen) > MAXPATHLEN) {
1539 log(LOG_ERR, "pid %d (%s), uid (%u): Path `%s%s' is too long\n",
1540 pid, name, uid, temp, name);
1541 free(temp, M_TEMP);
1542 return NULL;
1543 }
1544 memcpy(temp+n, name, namelen);
1545 n += namelen;
1546 break;
1547 case 'P': /* process id */
1548 l = sprintf(buf, "%u", pid);
1549 if ((n + l) > MAXPATHLEN) {
1550 log(LOG_ERR, "pid %d (%s), uid (%u): Path `%s%s' is too long\n",
1551 pid, name, uid, temp, name);
1552 free(temp, M_TEMP);
1553 return NULL;
1554 }
1555 memcpy(temp+n, buf, l);
1556 n += l;
1557 break;
1558 case 'U': /* user id */
1559 l = sprintf(buf, "%u", uid);
1560 if ((n + l) > MAXPATHLEN) {
1561 log(LOG_ERR, "pid %d (%s), uid (%u): Path `%s%s' is too long\n",
1562 pid, name, uid, temp, name);
1563 free(temp, M_TEMP);
1564 return NULL;
1565 }
1566 memcpy(temp+n, buf, l);
1567 n += l;
1568 break;
1569 default:
1570 log(LOG_ERR, "Unknown format character %c in `%s'\n", format[i], format);
1571 }
1572 break;
1573 default:
1574 temp[n++] = format[i];
1575 }
1576 }
1577 temp[n] = '\0';
1578 return temp;
1579}
1580
1581/*
1582 * Dump a process' core. The main routine does some
1583 * policy checking, and creates the name of the coredump;
1584 * then it passes on a vnode and a size limit to the process-specific
1585 * coredump routine if there is one; if there _is not_ one, it returns
1586 * ENOSYS; otherwise it returns the error from the process-specific routine.
1587 */
1588
1589static int
dadab5e9 1590coredump(struct proc *p)
984263bc 1591{
dadab5e9
MD
1592 struct vnode *vp;
1593 struct ucred *cred = p->p_ucred;
1594 struct thread *td = p->p_thread;
984263bc
MD
1595 struct flock lf;
1596 struct nameidata nd;
1597 struct vattr vattr;
1598 int error, error1;
1599 char *name; /* name of corefile */
1600 off_t limit;
1601
1602 STOPEVENT(p, S_CORE, 0);
1603
1604 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0)
1605 return (EFAULT);
1606
1607 /*
1608 * Note that the bulk of limit checking is done after
1609 * the corefile is created. The exception is if the limit
1610 * for corefiles is 0, in which case we don't bother
1611 * creating the corefile at all. This layout means that
1612 * a corefile is truncated instead of not being created,
1613 * if it is larger than the limit.
1614 */
1615 limit = p->p_rlimit[RLIMIT_CORE].rlim_cur;
1616 if (limit == 0)
1617 return 0;
1618
1619 name = expand_name(p->p_comm, p->p_ucred->cr_uid, p->p_pid);
1620 if (name == NULL)
1621 return (EINVAL);
dadab5e9 1622 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
984263bc
MD
1623 error = vn_open(&nd, O_CREAT | FWRITE | O_NOFOLLOW, S_IRUSR | S_IWUSR);
1624 free(name, M_TEMP);
1625 if (error)
1626 return (error);
1627 NDFREE(&nd, NDF_ONLY_PNBUF);
1628 vp = nd.ni_vp;
1629
dadab5e9 1630 VOP_UNLOCK(vp, 0, td);
984263bc
MD
1631 lf.l_whence = SEEK_SET;
1632 lf.l_start = 0;
1633 lf.l_len = 0;
1634 lf.l_type = F_WRLCK;
1635 error = VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK);
1636 if (error)
1637 goto out2;
1638
1639 /* Don't dump to non-regular files or files with links. */
1640 if (vp->v_type != VREG ||
3b568787 1641 VOP_GETATTR(vp, &vattr, td) || vattr.va_nlink != 1) {
984263bc
MD
1642 error = EFAULT;
1643 goto out1;
1644 }
1645
1646 VATTR_NULL(&vattr);
dadab5e9 1647 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
984263bc 1648 vattr.va_size = 0;
dadab5e9
MD
1649 VOP_LEASE(vp, td, cred, LEASE_WRITE);
1650 VOP_SETATTR(vp, &vattr, cred, td);
984263bc 1651 p->p_acflag |= ACORE;
dadab5e9 1652 VOP_UNLOCK(vp, 0, td);
984263bc
MD
1653
1654 error = p->p_sysent->sv_coredump ?
1655 p->p_sysent->sv_coredump(p, vp, limit) :
1656 ENOSYS;
1657
1658out1:
1659 lf.l_type = F_UNLCK;
1660 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
1661out2:
3b568787 1662 error1 = vn_close(vp, FWRITE, td);
984263bc
MD
1663 if (error == 0)
1664 error = error1;
1665 return (error);
1666}
1667
1668/*
1669 * Nonexistent system call-- signal process (may want to handle it).
1670 * Flag error in case process won't see signal immediately (blocked or ignored).
1671 */
1672#ifndef _SYS_SYSPROTO_H_
1673struct nosys_args {
1674 int dummy;
1675};
1676#endif
1677/* ARGSUSED */
1678int
41c20dac 1679nosys(struct nosys_args *args)
984263bc 1680{
41c20dac 1681 psignal(curproc, SIGSYS);
984263bc
MD
1682 return (EINVAL);
1683}
1684
1685/*
1686 * Send a SIGIO or SIGURG signal to a process or process group using
1687 * stored credentials rather than those of the current process.
1688 */
1689void
dadab5e9 1690pgsigio(struct sigio *sigio, int sig, int checkctty)
984263bc
MD
1691{
1692 if (sigio == NULL)
1693 return;
1694
1695 if (sigio->sio_pgid > 0) {
1696 if (CANSIGIO(sigio->sio_ruid, sigio->sio_ucred,
1697 sigio->sio_proc))
1698 psignal(sigio->sio_proc, sig);
1699 } else if (sigio->sio_pgid < 0) {
1700 struct proc *p;
1701
1702 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist)
1703 if (CANSIGIO(sigio->sio_ruid, sigio->sio_ucred, p) &&
1704 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
1705 psignal(p, sig);
1706 }
1707}
1708
1709static int
1710filt_sigattach(struct knote *kn)
1711{
1712 struct proc *p = curproc;
1713
1714 kn->kn_ptr.p_proc = p;
1715 kn->kn_flags |= EV_CLEAR; /* automatically set */
1716
1717 /* XXX lock the proc here while adding to the list? */
1718 SLIST_INSERT_HEAD(&p->p_klist, kn, kn_selnext);
1719
1720 return (0);
1721}
1722
1723static void
1724filt_sigdetach(struct knote *kn)
1725{
1726 struct proc *p = kn->kn_ptr.p_proc;
1727
1728 SLIST_REMOVE(&p->p_klist, kn, knote, kn_selnext);
1729}
1730
1731/*
1732 * signal knotes are shared with proc knotes, so we apply a mask to
1733 * the hint in order to differentiate them from process hints. This
1734 * could be avoided by using a signal-specific knote list, but probably
1735 * isn't worth the trouble.
1736 */
1737static int
1738filt_signal(struct knote *kn, long hint)
1739{
1740
1741 if (hint & NOTE_SIGNAL) {
1742 hint &= ~NOTE_SIGNAL;
1743
1744 if (kn->kn_id == hint)
1745 kn->kn_data++;
1746 }
1747 return (kn->kn_data != 0);
1748}