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.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
42 #include "opt_ktrace.h"
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
51 #include <sys/capsicum.h>
52 #include <sys/condvar.h>
53 #include <sys/event.h>
54 #include <sys/fcntl.h>
55 #include <sys/imgact.h>
56 #include <sys/kernel.h>
58 #include <sys/ktrace.h>
60 #include <sys/malloc.h>
61 #include <sys/mutex.h>
62 #include <sys/refcount.h>
63 #include <sys/namei.h>
65 #include <sys/procdesc.h>
66 #include <sys/posix4.h>
67 #include <sys/pioctl.h>
68 #include <sys/racct.h>
69 #include <sys/resourcevar.h>
72 #include <sys/sleepqueue.h>
76 #include <sys/syscallsubr.h>
77 #include <sys/sysctl.h>
78 #include <sys/sysent.h>
79 #include <sys/syslog.h>
80 #include <sys/sysproto.h>
81 #include <sys/timers.h>
82 #include <sys/unistd.h>
85 #include <vm/vm_extern.h>
90 #include <machine/cpu.h>
92 #include <security/audit/audit.h>
94 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE3(proc, , , signal__send,
98 "struct thread *", "struct proc *", "int");
99 SDT_PROBE_DEFINE2(proc, , , signal__clear,
100 "int", "ksiginfo_t *");
101 SDT_PROBE_DEFINE3(proc, , , signal__discard,
102 "struct thread *", "struct proc *", "int");
104 static int coredump(struct thread *);
105 static int killpg1(struct thread *td, int sig, int pgid, int all,
107 static int issignal(struct thread *td);
108 static int sigprop(int sig);
109 static void tdsigwakeup(struct thread *, int, sig_t, int);
110 static void sig_suspend_threads(struct thread *, struct proc *, int);
111 static int filt_sigattach(struct knote *kn);
112 static void filt_sigdetach(struct knote *kn);
113 static int filt_signal(struct knote *kn, long hint);
114 static struct thread *sigtd(struct proc *p, int sig, int prop);
115 static void sigqueue_start(void);
117 static uma_zone_t ksiginfo_zone = NULL;
118 struct filterops sig_filtops = {
120 .f_attach = filt_sigattach,
121 .f_detach = filt_sigdetach,
122 .f_event = filt_signal,
125 static int kern_logsigexit = 1;
126 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
128 "Log processes quitting on abnormal signals to syslog(3)");
130 static int kern_forcesigexit = 1;
131 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
132 &kern_forcesigexit, 0, "Force trap signal to be handled");
134 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
135 "POSIX real time signal");
137 static int max_pending_per_proc = 128;
138 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
139 &max_pending_per_proc, 0, "Max pending signals per proc");
141 static int preallocate_siginfo = 1024;
142 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
143 &preallocate_siginfo, 0, "Preallocated signal memory size");
145 static int signal_overflow = 0;
146 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
147 &signal_overflow, 0, "Number of signals overflew");
149 static int signal_alloc_fail = 0;
150 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
151 &signal_alloc_fail, 0, "signals failed to be allocated");
153 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
156 * Policy -- Can ucred cr1 send SIGIO to process cr2?
157 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
158 * in the right situations.
160 #define CANSIGIO(cr1, cr2) \
161 ((cr1)->cr_uid == 0 || \
162 (cr1)->cr_ruid == (cr2)->cr_ruid || \
163 (cr1)->cr_uid == (cr2)->cr_ruid || \
164 (cr1)->cr_ruid == (cr2)->cr_uid || \
165 (cr1)->cr_uid == (cr2)->cr_uid)
167 static int sugid_coredump;
168 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
169 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
171 static int capmode_coredump;
172 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
173 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
175 static int do_coredump = 1;
176 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
177 &do_coredump, 0, "Enable/Disable coredumps");
179 static int set_core_nodump_flag = 0;
180 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
181 0, "Enable setting the NODUMP flag on coredump files");
183 static int coredump_devctl = 0;
184 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
185 0, "Generate a devctl notification when processes coredump");
188 * Signal properties and actions.
189 * The array below categorizes the signals and their default actions
190 * according to the following properties:
192 #define SA_KILL 0x01 /* terminates process by default */
193 #define SA_CORE 0x02 /* ditto and coredumps */
194 #define SA_STOP 0x04 /* suspend process */
195 #define SA_TTYSTOP 0x08 /* ditto, from tty */
196 #define SA_IGNORE 0x10 /* ignore by default */
197 #define SA_CONT 0x20 /* continue if suspended */
198 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
200 static int sigproptbl[NSIG] = {
201 SA_KILL, /* SIGHUP */
202 SA_KILL, /* SIGINT */
203 SA_KILL|SA_CORE, /* SIGQUIT */
204 SA_KILL|SA_CORE, /* SIGILL */
205 SA_KILL|SA_CORE, /* SIGTRAP */
206 SA_KILL|SA_CORE, /* SIGABRT */
207 SA_KILL|SA_CORE, /* SIGEMT */
208 SA_KILL|SA_CORE, /* SIGFPE */
209 SA_KILL, /* SIGKILL */
210 SA_KILL|SA_CORE, /* SIGBUS */
211 SA_KILL|SA_CORE, /* SIGSEGV */
212 SA_KILL|SA_CORE, /* SIGSYS */
213 SA_KILL, /* SIGPIPE */
214 SA_KILL, /* SIGALRM */
215 SA_KILL, /* SIGTERM */
216 SA_IGNORE, /* SIGURG */
217 SA_STOP, /* SIGSTOP */
218 SA_STOP|SA_TTYSTOP, /* SIGTSTP */
219 SA_IGNORE|SA_CONT, /* SIGCONT */
220 SA_IGNORE, /* SIGCHLD */
221 SA_STOP|SA_TTYSTOP, /* SIGTTIN */
222 SA_STOP|SA_TTYSTOP, /* SIGTTOU */
223 SA_IGNORE, /* SIGIO */
224 SA_KILL, /* SIGXCPU */
225 SA_KILL, /* SIGXFSZ */
226 SA_KILL, /* SIGVTALRM */
227 SA_KILL, /* SIGPROF */
228 SA_IGNORE, /* SIGWINCH */
229 SA_IGNORE, /* SIGINFO */
230 SA_KILL, /* SIGUSR1 */
231 SA_KILL, /* SIGUSR2 */
234 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
239 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
240 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
241 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
242 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
243 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
244 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
248 ksiginfo_alloc(int wait)
255 if (ksiginfo_zone != NULL)
256 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
261 ksiginfo_free(ksiginfo_t *ksi)
263 uma_zfree(ksiginfo_zone, ksi);
267 ksiginfo_tryfree(ksiginfo_t *ksi)
269 if (!(ksi->ksi_flags & KSI_EXT)) {
270 uma_zfree(ksiginfo_zone, ksi);
277 sigqueue_init(sigqueue_t *list, struct proc *p)
279 SIGEMPTYSET(list->sq_signals);
280 SIGEMPTYSET(list->sq_kill);
281 TAILQ_INIT(&list->sq_list);
283 list->sq_flags = SQ_INIT;
287 * Get a signal's ksiginfo.
289 * 0 - signal not found
290 * others - signal number
293 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
295 struct proc *p = sq->sq_proc;
296 struct ksiginfo *ksi, *next;
299 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
301 if (!SIGISMEMBER(sq->sq_signals, signo))
304 if (SIGISMEMBER(sq->sq_kill, signo)) {
306 SIGDELSET(sq->sq_kill, signo);
309 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
310 if (ksi->ksi_signo == signo) {
312 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
313 ksi->ksi_sigq = NULL;
314 ksiginfo_copy(ksi, si);
315 if (ksiginfo_tryfree(ksi) && p != NULL)
324 SIGDELSET(sq->sq_signals, signo);
325 si->ksi_signo = signo;
330 sigqueue_take(ksiginfo_t *ksi)
336 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
340 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
341 ksi->ksi_sigq = NULL;
342 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
345 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
346 kp = TAILQ_NEXT(kp, ksi_link)) {
347 if (kp->ksi_signo == ksi->ksi_signo)
350 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
351 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
355 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
357 struct proc *p = sq->sq_proc;
358 struct ksiginfo *ksi;
361 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
363 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
364 SIGADDSET(sq->sq_kill, signo);
368 /* directly insert the ksi, don't copy it */
369 if (si->ksi_flags & KSI_INS) {
370 if (si->ksi_flags & KSI_HEAD)
371 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
373 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
378 if (__predict_false(ksiginfo_zone == NULL)) {
379 SIGADDSET(sq->sq_kill, signo);
383 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
386 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
392 ksiginfo_copy(si, ksi);
393 ksi->ksi_signo = signo;
394 if (si->ksi_flags & KSI_HEAD)
395 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
397 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
401 if ((si->ksi_flags & KSI_TRAP) != 0 ||
402 (si->ksi_flags & KSI_SIGQ) == 0) {
404 SIGADDSET(sq->sq_kill, signo);
413 SIGADDSET(sq->sq_signals, signo);
418 sigqueue_flush(sigqueue_t *sq)
420 struct proc *p = sq->sq_proc;
423 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
426 PROC_LOCK_ASSERT(p, MA_OWNED);
428 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
429 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
430 ksi->ksi_sigq = NULL;
431 if (ksiginfo_tryfree(ksi) && p != NULL)
435 SIGEMPTYSET(sq->sq_signals);
436 SIGEMPTYSET(sq->sq_kill);
440 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
443 struct proc *p1, *p2;
444 ksiginfo_t *ksi, *next;
446 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
447 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
450 /* Move siginfo to target list */
451 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
452 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
453 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
456 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
463 /* Move pending bits to target list */
465 SIGSETAND(tmp, *set);
466 SIGSETOR(dst->sq_kill, tmp);
467 SIGSETNAND(src->sq_kill, tmp);
469 tmp = src->sq_signals;
470 SIGSETAND(tmp, *set);
471 SIGSETOR(dst->sq_signals, tmp);
472 SIGSETNAND(src->sq_signals, tmp);
477 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
482 SIGADDSET(set, signo);
483 sigqueue_move_set(src, dst, &set);
488 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
490 struct proc *p = sq->sq_proc;
491 ksiginfo_t *ksi, *next;
493 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
495 /* Remove siginfo queue */
496 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
497 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
498 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
499 ksi->ksi_sigq = NULL;
500 if (ksiginfo_tryfree(ksi) && p != NULL)
504 SIGSETNAND(sq->sq_kill, *set);
505 SIGSETNAND(sq->sq_signals, *set);
509 sigqueue_delete(sigqueue_t *sq, int signo)
514 SIGADDSET(set, signo);
515 sigqueue_delete_set(sq, &set);
518 /* Remove a set of signals for a process */
520 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
525 PROC_LOCK_ASSERT(p, MA_OWNED);
527 sigqueue_init(&worklist, NULL);
528 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
530 FOREACH_THREAD_IN_PROC(p, td0)
531 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
533 sigqueue_flush(&worklist);
537 sigqueue_delete_proc(struct proc *p, int signo)
542 SIGADDSET(set, signo);
543 sigqueue_delete_set_proc(p, &set);
547 sigqueue_delete_stopmask_proc(struct proc *p)
552 SIGADDSET(set, SIGSTOP);
553 SIGADDSET(set, SIGTSTP);
554 SIGADDSET(set, SIGTTIN);
555 SIGADDSET(set, SIGTTOU);
556 sigqueue_delete_set_proc(p, &set);
560 * Determine signal that should be delivered to thread td, the current
561 * thread, 0 if none. If there is a pending stop signal with default
562 * action, the process stops in issignal().
565 cursig(struct thread *td)
567 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
568 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
569 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
570 return (SIGPENDING(td) ? issignal(td) : 0);
574 * Arrange for ast() to handle unmasked pending signals on return to user
575 * mode. This must be called whenever a signal is added to td_sigqueue or
576 * unmasked in td_sigmask.
579 signotify(struct thread *td)
585 PROC_LOCK_ASSERT(p, MA_OWNED);
587 if (SIGPENDING(td)) {
589 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
595 sigonstack(size_t sp)
597 struct thread *td = curthread;
599 return ((td->td_pflags & TDP_ALTSTACK) ?
600 #if defined(COMPAT_43)
601 ((td->td_sigstk.ss_size == 0) ?
602 (td->td_sigstk.ss_flags & SS_ONSTACK) :
603 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
605 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
614 if (sig > 0 && sig < NSIG)
615 return (sigproptbl[_SIG_IDX(sig)]);
620 sig_ffs(sigset_t *set)
624 for (i = 0; i < _SIG_WORDS; i++)
626 return (ffs(set->__bits[i]) + (i * 32));
631 sigact_flag_test(const struct sigaction *act, int flag)
635 * SA_SIGINFO is reset when signal disposition is set to
636 * ignore or default. Other flags are kept according to user
639 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
640 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
641 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
651 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
652 struct sigaction *oact, int flags)
655 struct proc *p = td->td_proc;
657 if (!_SIG_VALID(sig))
659 if (act != NULL && act->sa_handler != SIG_DFL &&
660 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
661 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
662 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
667 mtx_lock(&ps->ps_mtx);
669 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
671 if (SIGISMEMBER(ps->ps_sigonstack, sig))
672 oact->sa_flags |= SA_ONSTACK;
673 if (!SIGISMEMBER(ps->ps_sigintr, sig))
674 oact->sa_flags |= SA_RESTART;
675 if (SIGISMEMBER(ps->ps_sigreset, sig))
676 oact->sa_flags |= SA_RESETHAND;
677 if (SIGISMEMBER(ps->ps_signodefer, sig))
678 oact->sa_flags |= SA_NODEFER;
679 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
680 oact->sa_flags |= SA_SIGINFO;
682 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
684 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
685 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
686 oact->sa_flags |= SA_NOCLDSTOP;
687 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
688 oact->sa_flags |= SA_NOCLDWAIT;
691 if ((sig == SIGKILL || sig == SIGSTOP) &&
692 act->sa_handler != SIG_DFL) {
693 mtx_unlock(&ps->ps_mtx);
699 * Change setting atomically.
702 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
703 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
704 if (sigact_flag_test(act, SA_SIGINFO)) {
705 ps->ps_sigact[_SIG_IDX(sig)] =
706 (__sighandler_t *)act->sa_sigaction;
707 SIGADDSET(ps->ps_siginfo, sig);
709 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
710 SIGDELSET(ps->ps_siginfo, sig);
712 if (!sigact_flag_test(act, SA_RESTART))
713 SIGADDSET(ps->ps_sigintr, sig);
715 SIGDELSET(ps->ps_sigintr, sig);
716 if (sigact_flag_test(act, SA_ONSTACK))
717 SIGADDSET(ps->ps_sigonstack, sig);
719 SIGDELSET(ps->ps_sigonstack, sig);
720 if (sigact_flag_test(act, SA_RESETHAND))
721 SIGADDSET(ps->ps_sigreset, sig);
723 SIGDELSET(ps->ps_sigreset, sig);
724 if (sigact_flag_test(act, SA_NODEFER))
725 SIGADDSET(ps->ps_signodefer, sig);
727 SIGDELSET(ps->ps_signodefer, sig);
728 if (sig == SIGCHLD) {
729 if (act->sa_flags & SA_NOCLDSTOP)
730 ps->ps_flag |= PS_NOCLDSTOP;
732 ps->ps_flag &= ~PS_NOCLDSTOP;
733 if (act->sa_flags & SA_NOCLDWAIT) {
735 * Paranoia: since SA_NOCLDWAIT is implemented
736 * by reparenting the dying child to PID 1 (and
737 * trust it to reap the zombie), PID 1 itself
738 * is forbidden to set SA_NOCLDWAIT.
741 ps->ps_flag &= ~PS_NOCLDWAIT;
743 ps->ps_flag |= PS_NOCLDWAIT;
745 ps->ps_flag &= ~PS_NOCLDWAIT;
746 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
747 ps->ps_flag |= PS_CLDSIGIGN;
749 ps->ps_flag &= ~PS_CLDSIGIGN;
752 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
753 * and for signals set to SIG_DFL where the default is to
754 * ignore. However, don't put SIGCONT in ps_sigignore, as we
755 * have to restart the process.
757 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
758 (sigprop(sig) & SA_IGNORE &&
759 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
760 /* never to be seen again */
761 sigqueue_delete_proc(p, sig);
763 /* easier in psignal */
764 SIGADDSET(ps->ps_sigignore, sig);
765 SIGDELSET(ps->ps_sigcatch, sig);
767 SIGDELSET(ps->ps_sigignore, sig);
768 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
769 SIGDELSET(ps->ps_sigcatch, sig);
771 SIGADDSET(ps->ps_sigcatch, sig);
773 #ifdef COMPAT_FREEBSD4
774 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
775 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
776 (flags & KSA_FREEBSD4) == 0)
777 SIGDELSET(ps->ps_freebsd4, sig);
779 SIGADDSET(ps->ps_freebsd4, sig);
782 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
783 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
784 (flags & KSA_OSIGSET) == 0)
785 SIGDELSET(ps->ps_osigset, sig);
787 SIGADDSET(ps->ps_osigset, sig);
790 mtx_unlock(&ps->ps_mtx);
795 #ifndef _SYS_SYSPROTO_H_
796 struct sigaction_args {
798 struct sigaction *act;
799 struct sigaction *oact;
803 sys_sigaction(td, uap)
805 register struct sigaction_args *uap;
807 struct sigaction act, oact;
808 register struct sigaction *actp, *oactp;
811 actp = (uap->act != NULL) ? &act : NULL;
812 oactp = (uap->oact != NULL) ? &oact : NULL;
814 error = copyin(uap->act, actp, sizeof(act));
818 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
820 error = copyout(oactp, uap->oact, sizeof(oact));
824 #ifdef COMPAT_FREEBSD4
825 #ifndef _SYS_SYSPROTO_H_
826 struct freebsd4_sigaction_args {
828 struct sigaction *act;
829 struct sigaction *oact;
833 freebsd4_sigaction(td, uap)
835 register struct freebsd4_sigaction_args *uap;
837 struct sigaction act, oact;
838 register struct sigaction *actp, *oactp;
842 actp = (uap->act != NULL) ? &act : NULL;
843 oactp = (uap->oact != NULL) ? &oact : NULL;
845 error = copyin(uap->act, actp, sizeof(act));
849 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
851 error = copyout(oactp, uap->oact, sizeof(oact));
854 #endif /* COMAPT_FREEBSD4 */
856 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
857 #ifndef _SYS_SYSPROTO_H_
858 struct osigaction_args {
860 struct osigaction *nsa;
861 struct osigaction *osa;
867 register struct osigaction_args *uap;
869 struct osigaction sa;
870 struct sigaction nsa, osa;
871 register struct sigaction *nsap, *osap;
874 if (uap->signum <= 0 || uap->signum >= ONSIG)
877 nsap = (uap->nsa != NULL) ? &nsa : NULL;
878 osap = (uap->osa != NULL) ? &osa : NULL;
881 error = copyin(uap->nsa, &sa, sizeof(sa));
884 nsap->sa_handler = sa.sa_handler;
885 nsap->sa_flags = sa.sa_flags;
886 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
888 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
889 if (osap && !error) {
890 sa.sa_handler = osap->sa_handler;
891 sa.sa_flags = osap->sa_flags;
892 SIG2OSIG(osap->sa_mask, sa.sa_mask);
893 error = copyout(&sa, uap->osa, sizeof(sa));
898 #if !defined(__i386__)
899 /* Avoid replicating the same stub everywhere */
903 struct osigreturn_args *uap;
906 return (nosys(td, (struct nosys_args *)uap));
909 #endif /* COMPAT_43 */
912 * Initialize signal state for process 0;
913 * set to ignore signals that are ignored by default.
924 mtx_lock(&ps->ps_mtx);
925 for (i = 1; i <= NSIG; i++) {
926 if (sigprop(i) & SA_IGNORE && i != SIGCONT) {
927 SIGADDSET(ps->ps_sigignore, i);
930 mtx_unlock(&ps->ps_mtx);
935 * Reset specified signal to the default disposition.
938 sigdflt(struct sigacts *ps, int sig)
941 mtx_assert(&ps->ps_mtx, MA_OWNED);
942 SIGDELSET(ps->ps_sigcatch, sig);
943 if ((sigprop(sig) & SA_IGNORE) != 0 && sig != SIGCONT)
944 SIGADDSET(ps->ps_sigignore, sig);
945 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
946 SIGDELSET(ps->ps_siginfo, sig);
950 * Reset signals for an exec of the specified process.
953 execsigs(struct proc *p)
961 * Reset caught signals. Held signals remain held
962 * through td_sigmask (unless they were caught,
963 * and are now ignored by default).
965 PROC_LOCK_ASSERT(p, MA_OWNED);
966 td = FIRST_THREAD_IN_PROC(p);
968 mtx_lock(&ps->ps_mtx);
969 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
970 sig = sig_ffs(&ps->ps_sigcatch);
972 if ((sigprop(sig) & SA_IGNORE) != 0)
973 sigqueue_delete_proc(p, sig);
977 * As CloudABI processes cannot modify signal handlers, fully
978 * reset all signals to their default behavior. Do ignore
979 * SIGPIPE, as it would otherwise be impossible to recover from
980 * writes to broken pipes and sockets.
982 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
983 osigignore = ps->ps_sigignore;
984 while (SIGNOTEMPTY(osigignore)) {
985 sig = sig_ffs(&osigignore);
986 SIGDELSET(osigignore, sig);
990 SIGADDSET(ps->ps_sigignore, SIGPIPE);
994 * Reset stack state to the user stack.
995 * Clear set of signals caught on the signal stack.
997 td->td_sigstk.ss_flags = SS_DISABLE;
998 td->td_sigstk.ss_size = 0;
999 td->td_sigstk.ss_sp = 0;
1000 td->td_pflags &= ~TDP_ALTSTACK;
1002 * Reset no zombies if child dies flag as Solaris does.
1004 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1005 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1006 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1007 mtx_unlock(&ps->ps_mtx);
1011 * kern_sigprocmask()
1013 * Manipulate signal mask.
1016 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1019 sigset_t new_block, oset1;
1024 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1025 PROC_LOCK_ASSERT(p, MA_OWNED);
1028 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1029 ? MA_OWNED : MA_NOTOWNED);
1031 *oset = td->td_sigmask;
1038 oset1 = td->td_sigmask;
1039 SIGSETOR(td->td_sigmask, *set);
1040 new_block = td->td_sigmask;
1041 SIGSETNAND(new_block, oset1);
1044 SIGSETNAND(td->td_sigmask, *set);
1049 oset1 = td->td_sigmask;
1050 if (flags & SIGPROCMASK_OLD)
1051 SIGSETLO(td->td_sigmask, *set);
1053 td->td_sigmask = *set;
1054 new_block = td->td_sigmask;
1055 SIGSETNAND(new_block, oset1);
1064 * The new_block set contains signals that were not previously
1065 * blocked, but are blocked now.
1067 * In case we block any signal that was not previously blocked
1068 * for td, and process has the signal pending, try to schedule
1069 * signal delivery to some thread that does not block the
1070 * signal, possibly waking it up.
1072 if (p->p_numthreads != 1)
1073 reschedule_signals(p, new_block, flags);
1077 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1082 #ifndef _SYS_SYSPROTO_H_
1083 struct sigprocmask_args {
1085 const sigset_t *set;
1090 sys_sigprocmask(td, uap)
1091 register struct thread *td;
1092 struct sigprocmask_args *uap;
1095 sigset_t *setp, *osetp;
1098 setp = (uap->set != NULL) ? &set : NULL;
1099 osetp = (uap->oset != NULL) ? &oset : NULL;
1101 error = copyin(uap->set, setp, sizeof(set));
1105 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1106 if (osetp && !error) {
1107 error = copyout(osetp, uap->oset, sizeof(oset));
1112 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1113 #ifndef _SYS_SYSPROTO_H_
1114 struct osigprocmask_args {
1120 osigprocmask(td, uap)
1121 register struct thread *td;
1122 struct osigprocmask_args *uap;
1127 OSIG2SIG(uap->mask, set);
1128 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1129 SIG2OSIG(oset, td->td_retval[0]);
1132 #endif /* COMPAT_43 */
1135 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1141 error = copyin(uap->set, &set, sizeof(set));
1143 td->td_retval[0] = error;
1147 error = kern_sigtimedwait(td, set, &ksi, NULL);
1149 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1151 if (error == ERESTART)
1153 td->td_retval[0] = error;
1157 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1158 td->td_retval[0] = error;
1163 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1166 struct timespec *timeout;
1172 error = copyin(uap->timeout, &ts, sizeof(ts));
1180 error = copyin(uap->set, &set, sizeof(set));
1184 error = kern_sigtimedwait(td, set, &ksi, timeout);
1189 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1192 td->td_retval[0] = ksi.ksi_signo;
1197 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1203 error = copyin(uap->set, &set, sizeof(set));
1207 error = kern_sigtimedwait(td, set, &ksi, NULL);
1212 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1215 td->td_retval[0] = ksi.ksi_signo;
1220 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1221 struct timespec *timeout)
1224 sigset_t saved_mask, new_block;
1226 int error, sig, timo, timevalid = 0;
1227 struct timespec rts, ets, ts;
1235 if (timeout != NULL) {
1236 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1238 getnanouptime(&rts);
1240 timespecadd(&ets, timeout);
1244 /* Some signals can not be waited for. */
1245 SIG_CANTMASK(waitset);
1248 saved_mask = td->td_sigmask;
1249 SIGSETNAND(td->td_sigmask, waitset);
1251 mtx_lock(&ps->ps_mtx);
1253 mtx_unlock(&ps->ps_mtx);
1254 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1255 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1256 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1266 * POSIX says this must be checked after looking for pending
1269 if (timeout != NULL) {
1274 getnanouptime(&rts);
1275 if (timespeccmp(&rts, &ets, >=)) {
1280 timespecsub(&ts, &rts);
1281 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1287 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1289 if (timeout != NULL) {
1290 if (error == ERESTART) {
1291 /* Timeout can not be restarted. */
1293 } else if (error == EAGAIN) {
1294 /* We will calculate timeout by ourself. */
1300 new_block = saved_mask;
1301 SIGSETNAND(new_block, td->td_sigmask);
1302 td->td_sigmask = saved_mask;
1304 * Fewer signals can be delivered to us, reschedule signal
1307 if (p->p_numthreads != 1)
1308 reschedule_signals(p, new_block, 0);
1311 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1313 if (ksi->ksi_code == SI_TIMER)
1314 itimer_accept(p, ksi->ksi_timerid, ksi);
1317 if (KTRPOINT(td, KTR_PSIG)) {
1320 mtx_lock(&ps->ps_mtx);
1321 action = ps->ps_sigact[_SIG_IDX(sig)];
1322 mtx_unlock(&ps->ps_mtx);
1323 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1333 #ifndef _SYS_SYSPROTO_H_
1334 struct sigpending_args {
1339 sys_sigpending(td, uap)
1341 struct sigpending_args *uap;
1343 struct proc *p = td->td_proc;
1347 pending = p->p_sigqueue.sq_signals;
1348 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1350 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1353 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1354 #ifndef _SYS_SYSPROTO_H_
1355 struct osigpending_args {
1360 osigpending(td, uap)
1362 struct osigpending_args *uap;
1364 struct proc *p = td->td_proc;
1368 pending = p->p_sigqueue.sq_signals;
1369 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1371 SIG2OSIG(pending, td->td_retval[0]);
1374 #endif /* COMPAT_43 */
1376 #if defined(COMPAT_43)
1378 * Generalized interface signal handler, 4.3-compatible.
1380 #ifndef _SYS_SYSPROTO_H_
1381 struct osigvec_args {
1391 register struct osigvec_args *uap;
1394 struct sigaction nsa, osa;
1395 register struct sigaction *nsap, *osap;
1398 if (uap->signum <= 0 || uap->signum >= ONSIG)
1400 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1401 osap = (uap->osv != NULL) ? &osa : NULL;
1403 error = copyin(uap->nsv, &vec, sizeof(vec));
1406 nsap->sa_handler = vec.sv_handler;
1407 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1408 nsap->sa_flags = vec.sv_flags;
1409 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1411 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1412 if (osap && !error) {
1413 vec.sv_handler = osap->sa_handler;
1414 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1415 vec.sv_flags = osap->sa_flags;
1416 vec.sv_flags &= ~SA_NOCLDWAIT;
1417 vec.sv_flags ^= SA_RESTART;
1418 error = copyout(&vec, uap->osv, sizeof(vec));
1423 #ifndef _SYS_SYSPROTO_H_
1424 struct osigblock_args {
1430 register struct thread *td;
1431 struct osigblock_args *uap;
1435 OSIG2SIG(uap->mask, set);
1436 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1437 SIG2OSIG(oset, td->td_retval[0]);
1441 #ifndef _SYS_SYSPROTO_H_
1442 struct osigsetmask_args {
1447 osigsetmask(td, uap)
1449 struct osigsetmask_args *uap;
1453 OSIG2SIG(uap->mask, set);
1454 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1455 SIG2OSIG(oset, td->td_retval[0]);
1458 #endif /* COMPAT_43 */
1461 * Suspend calling thread until signal, providing mask to be set in the
1464 #ifndef _SYS_SYSPROTO_H_
1465 struct sigsuspend_args {
1466 const sigset_t *sigmask;
1471 sys_sigsuspend(td, uap)
1473 struct sigsuspend_args *uap;
1478 error = copyin(uap->sigmask, &mask, sizeof(mask));
1481 return (kern_sigsuspend(td, mask));
1485 kern_sigsuspend(struct thread *td, sigset_t mask)
1487 struct proc *p = td->td_proc;
1491 * When returning from sigsuspend, we want
1492 * the old mask to be restored after the
1493 * signal handler has finished. Thus, we
1494 * save it here and mark the sigacts structure
1498 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1499 SIGPROCMASK_PROC_LOCKED);
1500 td->td_pflags |= TDP_OLDMASK;
1503 * Process signals now. Otherwise, we can get spurious wakeup
1504 * due to signal entered process queue, but delivered to other
1505 * thread. But sigsuspend should return only on signal
1508 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1509 for (has_sig = 0; !has_sig;) {
1510 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1513 thread_suspend_check(0);
1514 mtx_lock(&p->p_sigacts->ps_mtx);
1515 while ((sig = cursig(td)) != 0)
1516 has_sig += postsig(sig);
1517 mtx_unlock(&p->p_sigacts->ps_mtx);
1520 td->td_errno = EINTR;
1521 td->td_pflags |= TDP_NERRNO;
1522 return (EJUSTRETURN);
1525 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1527 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1528 * convention: libc stub passes mask, not pointer, to save a copyin.
1530 #ifndef _SYS_SYSPROTO_H_
1531 struct osigsuspend_args {
1537 osigsuspend(td, uap)
1539 struct osigsuspend_args *uap;
1543 OSIG2SIG(uap->mask, mask);
1544 return (kern_sigsuspend(td, mask));
1546 #endif /* COMPAT_43 */
1548 #if defined(COMPAT_43)
1549 #ifndef _SYS_SYSPROTO_H_
1550 struct osigstack_args {
1551 struct sigstack *nss;
1552 struct sigstack *oss;
1559 register struct osigstack_args *uap;
1561 struct sigstack nss, oss;
1564 if (uap->nss != NULL) {
1565 error = copyin(uap->nss, &nss, sizeof(nss));
1569 oss.ss_sp = td->td_sigstk.ss_sp;
1570 oss.ss_onstack = sigonstack(cpu_getstack(td));
1571 if (uap->nss != NULL) {
1572 td->td_sigstk.ss_sp = nss.ss_sp;
1573 td->td_sigstk.ss_size = 0;
1574 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1575 td->td_pflags |= TDP_ALTSTACK;
1577 if (uap->oss != NULL)
1578 error = copyout(&oss, uap->oss, sizeof(oss));
1582 #endif /* COMPAT_43 */
1584 #ifndef _SYS_SYSPROTO_H_
1585 struct sigaltstack_args {
1592 sys_sigaltstack(td, uap)
1594 register struct sigaltstack_args *uap;
1599 if (uap->ss != NULL) {
1600 error = copyin(uap->ss, &ss, sizeof(ss));
1604 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1605 (uap->oss != NULL) ? &oss : NULL);
1608 if (uap->oss != NULL)
1609 error = copyout(&oss, uap->oss, sizeof(stack_t));
1614 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1616 struct proc *p = td->td_proc;
1619 oonstack = sigonstack(cpu_getstack(td));
1622 *oss = td->td_sigstk;
1623 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1624 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1630 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1632 if (!(ss->ss_flags & SS_DISABLE)) {
1633 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1636 td->td_sigstk = *ss;
1637 td->td_pflags |= TDP_ALTSTACK;
1639 td->td_pflags &= ~TDP_ALTSTACK;
1646 * Common code for kill process group/broadcast kill.
1647 * cp is calling process.
1650 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1662 sx_slock(&allproc_lock);
1663 FOREACH_PROC_IN_SYSTEM(p) {
1665 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1666 p == td->td_proc || p->p_state == PRS_NEW) {
1670 err = p_cansignal(td, p, sig);
1673 pksignal(p, sig, ksi);
1676 else if (ret == ESRCH)
1680 sx_sunlock(&allproc_lock);
1682 sx_slock(&proctree_lock);
1685 * zero pgid means send to my process group.
1687 pgrp = td->td_proc->p_pgrp;
1690 pgrp = pgfind(pgid);
1692 sx_sunlock(&proctree_lock);
1696 sx_sunlock(&proctree_lock);
1697 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1699 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1700 p->p_state == PRS_NEW) {
1704 err = p_cansignal(td, p, sig);
1707 pksignal(p, sig, ksi);
1710 else if (ret == ESRCH)
1719 #ifndef _SYS_SYSPROTO_H_
1727 sys_kill(struct thread *td, struct kill_args *uap)
1734 * A process in capability mode can send signals only to himself.
1735 * The main rationale behind this is that abort(3) is implemented as
1736 * kill(getpid(), SIGABRT).
1738 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1741 AUDIT_ARG_SIGNUM(uap->signum);
1742 AUDIT_ARG_PID(uap->pid);
1743 if ((u_int)uap->signum > _SIG_MAXSIG)
1746 ksiginfo_init(&ksi);
1747 ksi.ksi_signo = uap->signum;
1748 ksi.ksi_code = SI_USER;
1749 ksi.ksi_pid = td->td_proc->p_pid;
1750 ksi.ksi_uid = td->td_ucred->cr_ruid;
1753 /* kill single process */
1754 if ((p = pfind(uap->pid)) == NULL) {
1755 if ((p = zpfind(uap->pid)) == NULL)
1758 AUDIT_ARG_PROCESS(p);
1759 error = p_cansignal(td, p, uap->signum);
1760 if (error == 0 && uap->signum)
1761 pksignal(p, uap->signum, &ksi);
1766 case -1: /* broadcast signal */
1767 return (killpg1(td, uap->signum, 0, 1, &ksi));
1768 case 0: /* signal own process group */
1769 return (killpg1(td, uap->signum, 0, 0, &ksi));
1770 default: /* negative explicit process group */
1771 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1779 struct pdkill_args *uap;
1782 cap_rights_t rights;
1785 AUDIT_ARG_SIGNUM(uap->signum);
1786 AUDIT_ARG_FD(uap->fd);
1787 if ((u_int)uap->signum > _SIG_MAXSIG)
1790 error = procdesc_find(td, uap->fd,
1791 cap_rights_init(&rights, CAP_PDKILL), &p);
1794 AUDIT_ARG_PROCESS(p);
1795 error = p_cansignal(td, p, uap->signum);
1796 if (error == 0 && uap->signum)
1797 kern_psignal(p, uap->signum);
1802 #if defined(COMPAT_43)
1803 #ifndef _SYS_SYSPROTO_H_
1804 struct okillpg_args {
1811 okillpg(struct thread *td, struct okillpg_args *uap)
1815 AUDIT_ARG_SIGNUM(uap->signum);
1816 AUDIT_ARG_PID(uap->pgid);
1817 if ((u_int)uap->signum > _SIG_MAXSIG)
1820 ksiginfo_init(&ksi);
1821 ksi.ksi_signo = uap->signum;
1822 ksi.ksi_code = SI_USER;
1823 ksi.ksi_pid = td->td_proc->p_pid;
1824 ksi.ksi_uid = td->td_ucred->cr_ruid;
1825 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1827 #endif /* COMPAT_43 */
1829 #ifndef _SYS_SYSPROTO_H_
1830 struct sigqueue_args {
1833 /* union sigval */ void *value;
1837 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1843 if ((u_int)uap->signum > _SIG_MAXSIG)
1847 * Specification says sigqueue can only send signal to
1853 if ((p = pfind(uap->pid)) == NULL) {
1854 if ((p = zpfind(uap->pid)) == NULL)
1857 error = p_cansignal(td, p, uap->signum);
1858 if (error == 0 && uap->signum != 0) {
1859 ksiginfo_init(&ksi);
1860 ksi.ksi_flags = KSI_SIGQ;
1861 ksi.ksi_signo = uap->signum;
1862 ksi.ksi_code = SI_QUEUE;
1863 ksi.ksi_pid = td->td_proc->p_pid;
1864 ksi.ksi_uid = td->td_ucred->cr_ruid;
1865 ksi.ksi_value.sival_ptr = uap->value;
1866 error = pksignal(p, ksi.ksi_signo, &ksi);
1873 * Send a signal to a process group.
1876 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1881 sx_slock(&proctree_lock);
1882 pgrp = pgfind(pgid);
1883 sx_sunlock(&proctree_lock);
1885 pgsignal(pgrp, sig, 0, ksi);
1892 * Send a signal to a process group. If checktty is 1,
1893 * limit to members which have a controlling terminal.
1896 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1901 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1902 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1904 if (p->p_state == PRS_NORMAL &&
1905 (checkctty == 0 || p->p_flag & P_CONTROLT))
1906 pksignal(p, sig, ksi);
1914 * Recalculate the signal mask and reset the signal disposition after
1915 * usermode frame for delivery is formed. Should be called after
1916 * mach-specific routine, because sysent->sv_sendsig() needs correct
1917 * ps_siginfo and signal mask.
1920 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1924 mtx_assert(&ps->ps_mtx, MA_OWNED);
1925 td->td_ru.ru_nsignals++;
1926 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1927 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1928 SIGADDSET(mask, sig);
1929 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1930 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1931 if (SIGISMEMBER(ps->ps_sigreset, sig))
1937 * Send a signal caused by a trap to the current thread. If it will be
1938 * caught immediately, deliver it with correct code. Otherwise, post it
1942 trapsignal(struct thread *td, ksiginfo_t *ksi)
1950 sig = ksi->ksi_signo;
1951 code = ksi->ksi_code;
1952 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1956 mtx_lock(&ps->ps_mtx);
1957 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1958 !SIGISMEMBER(td->td_sigmask, sig)) {
1960 if (KTRPOINT(curthread, KTR_PSIG))
1961 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1962 &td->td_sigmask, code);
1964 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1965 ksi, &td->td_sigmask);
1966 postsig_done(sig, td, ps);
1967 mtx_unlock(&ps->ps_mtx);
1970 * Avoid a possible infinite loop if the thread
1971 * masking the signal or process is ignoring the
1974 if (kern_forcesigexit &&
1975 (SIGISMEMBER(td->td_sigmask, sig) ||
1976 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1977 SIGDELSET(td->td_sigmask, sig);
1978 SIGDELSET(ps->ps_sigcatch, sig);
1979 SIGDELSET(ps->ps_sigignore, sig);
1980 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1982 mtx_unlock(&ps->ps_mtx);
1983 p->p_code = code; /* XXX for core dump/debugger */
1984 p->p_sig = sig; /* XXX to verify code */
1985 tdsendsignal(p, td, sig, ksi);
1990 static struct thread *
1991 sigtd(struct proc *p, int sig, int prop)
1993 struct thread *td, *signal_td;
1995 PROC_LOCK_ASSERT(p, MA_OWNED);
1998 * Check if current thread can handle the signal without
1999 * switching context to another thread.
2001 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
2004 FOREACH_THREAD_IN_PROC(p, td) {
2005 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2010 if (signal_td == NULL)
2011 signal_td = FIRST_THREAD_IN_PROC(p);
2016 * Send the signal to the process. If the signal has an action, the action
2017 * is usually performed by the target process rather than the caller; we add
2018 * the signal to the set of pending signals for the process.
2021 * o When a stop signal is sent to a sleeping process that takes the
2022 * default action, the process is stopped without awakening it.
2023 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2024 * regardless of the signal action (eg, blocked or ignored).
2026 * Other ignored signals are discarded immediately.
2028 * NB: This function may be entered from the debugger via the "kill" DDB
2029 * command. There is little that can be done to mitigate the possibly messy
2030 * side effects of this unwise possibility.
2033 kern_psignal(struct proc *p, int sig)
2037 ksiginfo_init(&ksi);
2038 ksi.ksi_signo = sig;
2039 ksi.ksi_code = SI_KERNEL;
2040 (void) tdsendsignal(p, NULL, sig, &ksi);
2044 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2047 return (tdsendsignal(p, NULL, sig, ksi));
2050 /* Utility function for finding a thread to send signal event to. */
2052 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2056 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2057 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2069 tdsignal(struct thread *td, int sig)
2073 ksiginfo_init(&ksi);
2074 ksi.ksi_signo = sig;
2075 ksi.ksi_code = SI_KERNEL;
2076 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2080 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2083 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2087 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2090 sigqueue_t *sigqueue;
2097 MPASS(td == NULL || p == td->td_proc);
2098 PROC_LOCK_ASSERT(p, MA_OWNED);
2100 if (!_SIG_VALID(sig))
2101 panic("%s(): invalid signal %d", __func__, sig);
2103 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2106 * IEEE Std 1003.1-2001: return success when killing a zombie.
2108 if (p->p_state == PRS_ZOMBIE) {
2109 if (ksi && (ksi->ksi_flags & KSI_INS))
2110 ksiginfo_tryfree(ksi);
2115 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2116 prop = sigprop(sig);
2119 td = sigtd(p, sig, prop);
2120 sigqueue = &p->p_sigqueue;
2122 sigqueue = &td->td_sigqueue;
2124 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2127 * If the signal is being ignored,
2128 * then we forget about it immediately.
2129 * (Note: we don't set SIGCONT in ps_sigignore,
2130 * and if it is set to SIG_IGN,
2131 * action will be SIG_DFL here.)
2133 mtx_lock(&ps->ps_mtx);
2134 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2135 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2137 mtx_unlock(&ps->ps_mtx);
2138 if (ksi && (ksi->ksi_flags & KSI_INS))
2139 ksiginfo_tryfree(ksi);
2142 if (SIGISMEMBER(td->td_sigmask, sig))
2144 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2148 if (SIGISMEMBER(ps->ps_sigintr, sig))
2152 mtx_unlock(&ps->ps_mtx);
2155 sigqueue_delete_stopmask_proc(p);
2156 else if (prop & SA_STOP) {
2158 * If sending a tty stop signal to a member of an orphaned
2159 * process group, discard the signal here if the action
2160 * is default; don't stop the process below if sleeping,
2161 * and don't clear any pending SIGCONT.
2163 if ((prop & SA_TTYSTOP) &&
2164 (p->p_pgrp->pg_jobc == 0) &&
2165 (action == SIG_DFL)) {
2166 if (ksi && (ksi->ksi_flags & KSI_INS))
2167 ksiginfo_tryfree(ksi);
2170 sigqueue_delete_proc(p, SIGCONT);
2171 if (p->p_flag & P_CONTINUED) {
2172 p->p_flag &= ~P_CONTINUED;
2173 PROC_LOCK(p->p_pptr);
2174 sigqueue_take(p->p_ksi);
2175 PROC_UNLOCK(p->p_pptr);
2179 ret = sigqueue_add(sigqueue, sig, ksi);
2184 * Defer further processing for signals which are held,
2185 * except that stopped processes must be continued by SIGCONT.
2187 if (action == SIG_HOLD &&
2188 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2191 * SIGKILL: Remove procfs STOPEVENTs.
2193 if (sig == SIGKILL) {
2194 /* from procfs_ioctl.c: PIOCBIC */
2196 /* from procfs_ioctl.c: PIOCCONT */
2201 * Some signals have a process-wide effect and a per-thread
2202 * component. Most processing occurs when the process next
2203 * tries to cross the user boundary, however there are some
2204 * times when processing needs to be done immediately, such as
2205 * waking up threads so that they can cross the user boundary.
2206 * We try to do the per-process part here.
2208 if (P_SHOULDSTOP(p)) {
2209 KASSERT(!(p->p_flag & P_WEXIT),
2210 ("signal to stopped but exiting process"));
2211 if (sig == SIGKILL) {
2213 * If traced process is already stopped,
2214 * then no further action is necessary.
2216 if (p->p_flag & P_TRACED)
2219 * SIGKILL sets process running.
2220 * It will die elsewhere.
2221 * All threads must be restarted.
2223 p->p_flag &= ~P_STOPPED_SIG;
2227 if (prop & SA_CONT) {
2229 * If traced process is already stopped,
2230 * then no further action is necessary.
2232 if (p->p_flag & P_TRACED)
2235 * If SIGCONT is default (or ignored), we continue the
2236 * process but don't leave the signal in sigqueue as
2237 * it has no further action. If SIGCONT is held, we
2238 * continue the process and leave the signal in
2239 * sigqueue. If the process catches SIGCONT, let it
2240 * handle the signal itself. If it isn't waiting on
2241 * an event, it goes back to run state.
2242 * Otherwise, process goes back to sleep state.
2244 p->p_flag &= ~P_STOPPED_SIG;
2246 if (p->p_numthreads == p->p_suspcount) {
2248 p->p_flag |= P_CONTINUED;
2249 p->p_xsig = SIGCONT;
2250 PROC_LOCK(p->p_pptr);
2251 childproc_continued(p);
2252 PROC_UNLOCK(p->p_pptr);
2255 if (action == SIG_DFL) {
2256 thread_unsuspend(p);
2258 sigqueue_delete(sigqueue, sig);
2261 if (action == SIG_CATCH) {
2263 * The process wants to catch it so it needs
2264 * to run at least one thread, but which one?
2270 * The signal is not ignored or caught.
2272 thread_unsuspend(p);
2277 if (prop & SA_STOP) {
2279 * If traced process is already stopped,
2280 * then no further action is necessary.
2282 if (p->p_flag & P_TRACED)
2285 * Already stopped, don't need to stop again
2286 * (If we did the shell could get confused).
2287 * Just make sure the signal STOP bit set.
2289 p->p_flag |= P_STOPPED_SIG;
2290 sigqueue_delete(sigqueue, sig);
2295 * All other kinds of signals:
2296 * If a thread is sleeping interruptibly, simulate a
2297 * wakeup so that when it is continued it will be made
2298 * runnable and can look at the signal. However, don't make
2299 * the PROCESS runnable, leave it stopped.
2300 * It may run a bit until it hits a thread_suspend_check().
2305 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2306 wakeup_swapper = sleepq_abort(td, intrval);
2313 * Mutexes are short lived. Threads waiting on them will
2314 * hit thread_suspend_check() soon.
2316 } else if (p->p_state == PRS_NORMAL) {
2317 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2318 tdsigwakeup(td, sig, action, intrval);
2322 MPASS(action == SIG_DFL);
2324 if (prop & SA_STOP) {
2325 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2327 p->p_flag |= P_STOPPED_SIG;
2330 sig_suspend_threads(td, p, 1);
2331 if (p->p_numthreads == p->p_suspcount) {
2333 * only thread sending signal to another
2334 * process can reach here, if thread is sending
2335 * signal to its process, because thread does
2336 * not suspend itself here, p_numthreads
2337 * should never be equal to p_suspcount.
2341 sigqueue_delete_proc(p, p->p_xsig);
2347 /* Not in "NORMAL" state. discard the signal. */
2348 sigqueue_delete(sigqueue, sig);
2353 * The process is not stopped so we need to apply the signal to all the
2357 tdsigwakeup(td, sig, action, intrval);
2359 thread_unsuspend(p);
2362 /* If we jump here, proc slock should not be owned. */
2363 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2368 * The force of a signal has been directed against a single
2369 * thread. We need to see what we can do about knocking it
2370 * out of any sleep it may be in etc.
2373 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2375 struct proc *p = td->td_proc;
2380 PROC_LOCK_ASSERT(p, MA_OWNED);
2381 prop = sigprop(sig);
2386 * Bring the priority of a thread up if we want it to get
2387 * killed in this lifetime. Be careful to avoid bumping the
2388 * priority of the idle thread, since we still allow to signal
2391 if (action == SIG_DFL && (prop & SA_KILL) != 0 &&
2392 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2393 sched_prio(td, PUSER);
2394 if (TD_ON_SLEEPQ(td)) {
2396 * If thread is sleeping uninterruptibly
2397 * we can't interrupt the sleep... the signal will
2398 * be noticed when the process returns through
2399 * trap() or syscall().
2401 if ((td->td_flags & TDF_SINTR) == 0)
2404 * If SIGCONT is default (or ignored) and process is
2405 * asleep, we are finished; the process should not
2408 if ((prop & SA_CONT) && action == SIG_DFL) {
2411 sigqueue_delete(&p->p_sigqueue, sig);
2413 * It may be on either list in this state.
2414 * Remove from both for now.
2416 sigqueue_delete(&td->td_sigqueue, sig);
2421 * Don't awaken a sleeping thread for SIGSTOP if the
2422 * STOP signal is deferred.
2424 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2428 * Give low priority threads a better chance to run.
2430 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2431 sched_prio(td, PUSER);
2433 wakeup_swapper = sleepq_abort(td, intrval);
2436 * Other states do nothing with the signal immediately,
2437 * other than kicking ourselves if we are running.
2438 * It will either never be noticed, or noticed very soon.
2441 if (TD_IS_RUNNING(td) && td != curthread)
2453 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2457 PROC_LOCK_ASSERT(p, MA_OWNED);
2458 PROC_SLOCK_ASSERT(p, MA_OWNED);
2460 FOREACH_THREAD_IN_PROC(p, td2) {
2462 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2463 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2464 (td2->td_flags & TDF_SINTR)) {
2465 if (td2->td_flags & TDF_SBDRY) {
2467 * Once a thread is asleep with
2468 * TDF_SBDRY set, it should never
2469 * become suspended due to this check.
2471 KASSERT(!TD_IS_SUSPENDED(td2),
2472 ("thread with deferred stops suspended"));
2473 } else if (!TD_IS_SUSPENDED(td2)) {
2474 thread_suspend_one(td2);
2476 } else if (!TD_IS_SUSPENDED(td2)) {
2477 if (sending || td != td2)
2478 td2->td_flags |= TDF_ASTPENDING;
2480 if (TD_IS_RUNNING(td2) && td2 != td)
2481 forward_signal(td2);
2489 ptracestop(struct thread *td, int sig)
2491 struct proc *p = td->td_proc;
2493 PROC_LOCK_ASSERT(p, MA_OWNED);
2494 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2495 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2496 &p->p_mtx.lock_object, "Stopping for traced signal");
2498 td->td_dbgflags |= TDB_XSIG;
2500 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2501 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2503 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2504 if (p->p_flag & P_SINGLE_EXIT &&
2505 !(td->td_dbgflags & TDB_EXIT)) {
2507 * Ignore ptrace stops except for thread exit
2508 * events when the process exits.
2510 td->td_dbgflags &= ~TDB_XSIG;
2515 * Just make wait() to work, the last stopped thread
2520 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2521 sig_suspend_threads(td, p, 0);
2522 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2523 td->td_dbgflags &= ~TDB_STOPATFORK;
2524 cv_broadcast(&p->p_dbgwait);
2527 thread_suspend_switch(td, p);
2528 if (p->p_xthread == td)
2529 p->p_xthread = NULL;
2530 if (!(p->p_flag & P_TRACED))
2532 if (td->td_dbgflags & TDB_SUSPEND) {
2533 if (p->p_flag & P_SINGLE_EXIT)
2539 return (td->td_xsig);
2543 reschedule_signals(struct proc *p, sigset_t block, int flags)
2549 PROC_LOCK_ASSERT(p, MA_OWNED);
2551 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2552 MA_OWNED : MA_NOTOWNED);
2553 if (SIGISEMPTY(p->p_siglist))
2555 SIGSETAND(block, p->p_siglist);
2556 while ((sig = sig_ffs(&block)) != 0) {
2557 SIGDELSET(block, sig);
2558 td = sigtd(p, sig, 0);
2560 if (!(flags & SIGPROCMASK_PS_LOCKED))
2561 mtx_lock(&ps->ps_mtx);
2562 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2563 tdsigwakeup(td, sig, SIG_CATCH,
2564 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2566 if (!(flags & SIGPROCMASK_PS_LOCKED))
2567 mtx_unlock(&ps->ps_mtx);
2572 tdsigcleanup(struct thread *td)
2578 PROC_LOCK_ASSERT(p, MA_OWNED);
2580 sigqueue_flush(&td->td_sigqueue);
2581 if (p->p_numthreads == 1)
2585 * Since we cannot handle signals, notify signal post code
2586 * about this by filling the sigmask.
2588 * Also, if needed, wake up thread(s) that do not block the
2589 * same signals as the exiting thread, since the thread might
2590 * have been selected for delivery and woken up.
2592 SIGFILLSET(unblocked);
2593 SIGSETNAND(unblocked, td->td_sigmask);
2594 SIGFILLSET(td->td_sigmask);
2595 reschedule_signals(p, unblocked, 0);
2600 * Defer the delivery of SIGSTOP for the current thread. Returns true
2601 * if stops were deferred and false if they were already deferred.
2609 if (td->td_flags & TDF_SBDRY)
2612 td->td_flags |= TDF_SBDRY;
2618 * Permit the delivery of SIGSTOP for the current thread. This does
2619 * not immediately suspend if a stop was posted. Instead, the thread
2620 * will suspend either via ast() or a subsequent interruptible sleep.
2630 prev = (td->td_flags & TDF_SBDRY) != 0;
2631 td->td_flags &= ~TDF_SBDRY;
2637 * If the current process has received a signal (should be caught or cause
2638 * termination, should interrupt current syscall), return the signal number.
2639 * Stop signals with default action are processed immediately, then cleared;
2640 * they aren't returned. This is checked after each entry to the system for
2641 * a syscall or trap (though this can usually be done without calling issignal
2642 * by checking the pending signal masks in cursig.) The normal call
2645 * while (sig = cursig(curthread))
2649 issignal(struct thread *td)
2653 struct sigqueue *queue;
2654 sigset_t sigpending;
2655 int sig, prop, newsig;
2659 mtx_assert(&ps->ps_mtx, MA_OWNED);
2660 PROC_LOCK_ASSERT(p, MA_OWNED);
2662 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2664 sigpending = td->td_sigqueue.sq_signals;
2665 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2666 SIGSETNAND(sigpending, td->td_sigmask);
2668 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2669 SIG_STOPSIGMASK(sigpending);
2670 if (SIGISEMPTY(sigpending)) /* no signal to send */
2672 sig = sig_ffs(&sigpending);
2674 if (p->p_stops & S_SIG) {
2675 mtx_unlock(&ps->ps_mtx);
2676 stopevent(p, S_SIG, sig);
2677 mtx_lock(&ps->ps_mtx);
2681 * We should see pending but ignored signals
2682 * only if P_TRACED was on when they were posted.
2684 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2685 sigqueue_delete(&td->td_sigqueue, sig);
2686 sigqueue_delete(&p->p_sigqueue, sig);
2689 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) {
2691 * If traced, always stop.
2692 * Remove old signal from queue before the stop.
2693 * XXX shrug off debugger, it causes siginfo to
2696 queue = &td->td_sigqueue;
2697 td->td_dbgksi.ksi_signo = 0;
2698 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2699 queue = &p->p_sigqueue;
2700 sigqueue_get(queue, sig, &td->td_dbgksi);
2703 mtx_unlock(&ps->ps_mtx);
2704 newsig = ptracestop(td, sig);
2705 mtx_lock(&ps->ps_mtx);
2707 if (sig != newsig) {
2710 * If parent wants us to take the signal,
2711 * then it will leave it in p->p_xsig;
2712 * otherwise we just look for signals again.
2719 * Put the new signal into td_sigqueue. If the
2720 * signal is being masked, look for other
2723 sigqueue_add(queue, sig, NULL);
2724 if (SIGISMEMBER(td->td_sigmask, sig))
2728 if (td->td_dbgksi.ksi_signo != 0) {
2729 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2730 if (sigqueue_add(&td->td_sigqueue, sig,
2731 &td->td_dbgksi) != 0)
2732 td->td_dbgksi.ksi_signo = 0;
2734 if (td->td_dbgksi.ksi_signo == 0)
2735 sigqueue_add(&td->td_sigqueue, sig,
2740 * If the traced bit got turned off, go back up
2741 * to the top to rescan signals. This ensures
2742 * that p_sig* and p_sigact are consistent.
2744 if ((p->p_flag & P_TRACED) == 0)
2748 prop = sigprop(sig);
2751 * Decide whether the signal should be returned.
2752 * Return the signal's number, or fall through
2753 * to clear it from the pending mask.
2755 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2757 case (intptr_t)SIG_DFL:
2759 * Don't take default actions on system processes.
2761 if (p->p_pid <= 1) {
2764 * Are you sure you want to ignore SIGSEGV
2767 printf("Process (pid %lu) got signal %d\n",
2768 (u_long)p->p_pid, sig);
2770 break; /* == ignore */
2773 * If there is a pending stop signal to process
2774 * with default action, stop here,
2775 * then clear the signal. However,
2776 * if process is member of an orphaned
2777 * process group, ignore tty stop signals.
2779 if (prop & SA_STOP) {
2780 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2781 (p->p_pgrp->pg_jobc == 0 &&
2783 break; /* == ignore */
2784 mtx_unlock(&ps->ps_mtx);
2785 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2786 &p->p_mtx.lock_object, "Catching SIGSTOP");
2787 p->p_flag |= P_STOPPED_SIG;
2790 sig_suspend_threads(td, p, 0);
2791 thread_suspend_switch(td, p);
2793 mtx_lock(&ps->ps_mtx);
2795 } else if (prop & SA_IGNORE) {
2797 * Except for SIGCONT, shouldn't get here.
2798 * Default action is to ignore; drop it.
2800 break; /* == ignore */
2805 case (intptr_t)SIG_IGN:
2807 * Masking above should prevent us ever trying
2808 * to take action on an ignored signal other
2809 * than SIGCONT, unless process is traced.
2811 if ((prop & SA_CONT) == 0 &&
2812 (p->p_flag & P_TRACED) == 0)
2813 printf("issignal\n");
2814 break; /* == ignore */
2818 * This signal has an action, let
2819 * postsig() process it.
2823 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2824 sigqueue_delete(&p->p_sigqueue, sig);
2830 thread_stopped(struct proc *p)
2834 PROC_LOCK_ASSERT(p, MA_OWNED);
2835 PROC_SLOCK_ASSERT(p, MA_OWNED);
2839 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2841 p->p_flag &= ~P_WAITED;
2842 PROC_LOCK(p->p_pptr);
2843 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2844 CLD_TRAPPED : CLD_STOPPED);
2845 PROC_UNLOCK(p->p_pptr);
2851 * Take the action for the specified signal
2852 * from the current set of pending signals.
2858 struct thread *td = curthread;
2859 register struct proc *p = td->td_proc;
2863 sigset_t returnmask;
2865 KASSERT(sig != 0, ("postsig"));
2867 PROC_LOCK_ASSERT(p, MA_OWNED);
2869 mtx_assert(&ps->ps_mtx, MA_OWNED);
2870 ksiginfo_init(&ksi);
2871 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2872 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2874 ksi.ksi_signo = sig;
2875 if (ksi.ksi_code == SI_TIMER)
2876 itimer_accept(p, ksi.ksi_timerid, &ksi);
2877 action = ps->ps_sigact[_SIG_IDX(sig)];
2879 if (KTRPOINT(td, KTR_PSIG))
2880 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2881 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2883 if (p->p_stops & S_SIG) {
2884 mtx_unlock(&ps->ps_mtx);
2885 stopevent(p, S_SIG, sig);
2886 mtx_lock(&ps->ps_mtx);
2889 if (action == SIG_DFL) {
2891 * Default action, where the default is to kill
2892 * the process. (Other cases were ignored above.)
2894 mtx_unlock(&ps->ps_mtx);
2899 * If we get here, the signal must be caught.
2901 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2902 ("postsig action"));
2904 * Set the new mask value and also defer further
2905 * occurrences of this signal.
2907 * Special case: user has done a sigsuspend. Here the
2908 * current mask is not of interest, but rather the
2909 * mask from before the sigsuspend is what we want
2910 * restored after the signal processing is completed.
2912 if (td->td_pflags & TDP_OLDMASK) {
2913 returnmask = td->td_oldsigmask;
2914 td->td_pflags &= ~TDP_OLDMASK;
2916 returnmask = td->td_sigmask;
2918 if (p->p_sig == sig) {
2922 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2923 postsig_done(sig, td, ps);
2929 * Kill the current process for stated reason.
2937 PROC_LOCK_ASSERT(p, MA_OWNED);
2938 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2940 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2941 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2942 p->p_flag |= P_WKILLED;
2943 kern_psignal(p, SIGKILL);
2947 * Force the current process to exit with the specified signal, dumping core
2948 * if appropriate. We bypass the normal tests for masked and caught signals,
2949 * allowing unrecoverable failures to terminate the process without changing
2950 * signal state. Mark the accounting record with the signal termination.
2951 * If dumping core, save the signal number for the debugger. Calls exit and
2959 struct proc *p = td->td_proc;
2961 PROC_LOCK_ASSERT(p, MA_OWNED);
2962 p->p_acflag |= AXSIG;
2964 * We must be single-threading to generate a core dump. This
2965 * ensures that the registers in the core file are up-to-date.
2966 * Also, the ELF dump handler assumes that the thread list doesn't
2967 * change out from under it.
2969 * XXX If another thread attempts to single-thread before us
2970 * (e.g. via fork()), we won't get a dump at all.
2972 if ((sigprop(sig) & SA_CORE) && thread_single(p, SINGLE_NO_EXIT) == 0) {
2975 * Log signals which would cause core dumps
2976 * (Log as LOG_INFO to appease those who don't want
2978 * XXX : Todo, as well as euid, write out ruid too
2979 * Note that coredump() drops proc lock.
2981 if (coredump(td) == 0)
2983 if (kern_logsigexit)
2985 "pid %d (%s), uid %d: exited on signal %d%s\n",
2986 p->p_pid, p->p_comm,
2987 td->td_ucred ? td->td_ucred->cr_uid : -1,
2989 sig & WCOREFLAG ? " (core dumped)" : "");
2997 * Send queued SIGCHLD to parent when child process's state
3001 sigparent(struct proc *p, int reason, int status)
3003 PROC_LOCK_ASSERT(p, MA_OWNED);
3004 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3006 if (p->p_ksi != NULL) {
3007 p->p_ksi->ksi_signo = SIGCHLD;
3008 p->p_ksi->ksi_code = reason;
3009 p->p_ksi->ksi_status = status;
3010 p->p_ksi->ksi_pid = p->p_pid;
3011 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3012 if (KSI_ONQ(p->p_ksi))
3015 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3019 childproc_jobstate(struct proc *p, int reason, int sig)
3023 PROC_LOCK_ASSERT(p, MA_OWNED);
3024 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3027 * Wake up parent sleeping in kern_wait(), also send
3028 * SIGCHLD to parent, but SIGCHLD does not guarantee
3029 * that parent will awake, because parent may masked
3032 p->p_pptr->p_flag |= P_STATCHILD;
3035 ps = p->p_pptr->p_sigacts;
3036 mtx_lock(&ps->ps_mtx);
3037 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3038 mtx_unlock(&ps->ps_mtx);
3039 sigparent(p, reason, sig);
3041 mtx_unlock(&ps->ps_mtx);
3045 childproc_stopped(struct proc *p, int reason)
3048 childproc_jobstate(p, reason, p->p_xsig);
3052 childproc_continued(struct proc *p)
3054 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3058 childproc_exited(struct proc *p)
3062 if (WCOREDUMP(p->p_xsig)) {
3063 reason = CLD_DUMPED;
3064 status = WTERMSIG(p->p_xsig);
3065 } else if (WIFSIGNALED(p->p_xsig)) {
3066 reason = CLD_KILLED;
3067 status = WTERMSIG(p->p_xsig);
3069 reason = CLD_EXITED;
3070 status = p->p_xexit;
3073 * XXX avoid calling wakeup(p->p_pptr), the work is
3076 sigparent(p, reason, status);
3080 * We only have 1 character for the core count in the format
3081 * string, so the range will be 0-9
3083 #define MAX_NUM_CORES 10
3084 static int num_cores = 5;
3087 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3092 new_val = num_cores;
3093 error = sysctl_handle_int(oidp, &new_val, 0, req);
3094 if (error != 0 || req->newptr == NULL)
3096 if (new_val > MAX_NUM_CORES)
3097 new_val = MAX_NUM_CORES;
3100 num_cores = new_val;
3103 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3104 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3106 #define GZ_SUFFIX ".gz"
3109 static int compress_user_cores = 1;
3110 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RWTUN,
3111 &compress_user_cores, 0, "Compression of user corefiles");
3113 int compress_user_cores_gzlevel = 6;
3114 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RWTUN,
3115 &compress_user_cores_gzlevel, 0, "Corefile gzip compression level");
3117 static int compress_user_cores = 0;
3121 * Protect the access to corefilename[] by allproc_lock.
3123 #define corefilename_lock allproc_lock
3125 static char corefilename[MAXPATHLEN] = {"%N.core"};
3126 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3129 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3133 sx_xlock(&corefilename_lock);
3134 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3136 sx_xunlock(&corefilename_lock);
3140 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3141 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3142 "Process corefile name format string");
3145 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3146 * Expand the name described in corefilename, using name, uid, and pid
3147 * and open/create core file.
3148 * corefilename is a printf-like string, with three format specifiers:
3149 * %N name of process ("name")
3150 * %P process id (pid)
3152 * For example, "%N.core" is the default; they can be disabled completely
3153 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3154 * This is controlled by the sysctl variable kern.corefile (see above).
3157 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3158 int compress, struct vnode **vpp, char **namep)
3160 struct nameidata nd;
3163 char *hostname, *name;
3164 int indexpos, i, error, cmode, flags, oflags;
3167 format = corefilename;
3168 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3170 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3171 sx_slock(&corefilename_lock);
3172 for (i = 0; format[i] != '\0'; i++) {
3173 switch (format[i]) {
3174 case '%': /* Format character */
3176 switch (format[i]) {
3178 sbuf_putc(&sb, '%');
3180 case 'H': /* hostname */
3181 if (hostname == NULL) {
3182 hostname = malloc(MAXHOSTNAMELEN,
3185 getcredhostname(td->td_ucred, hostname,
3187 sbuf_printf(&sb, "%s", hostname);
3189 case 'I': /* autoincrementing index */
3190 sbuf_printf(&sb, "0");
3191 indexpos = sbuf_len(&sb) - 1;
3193 case 'N': /* process name */
3194 sbuf_printf(&sb, "%s", comm);
3196 case 'P': /* process id */
3197 sbuf_printf(&sb, "%u", pid);
3199 case 'U': /* user id */
3200 sbuf_printf(&sb, "%u", uid);
3204 "Unknown format character %c in "
3205 "corename `%s'\n", format[i], format);
3210 sbuf_putc(&sb, format[i]);
3214 sx_sunlock(&corefilename_lock);
3215 free(hostname, M_TEMP);
3217 sbuf_printf(&sb, GZ_SUFFIX);
3218 if (sbuf_error(&sb) != 0) {
3219 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3220 "long\n", (long)pid, comm, (u_long)uid);
3228 cmode = S_IRUSR | S_IWUSR;
3229 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3230 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3233 * If the core format has a %I in it, then we need to check
3234 * for existing corefiles before returning a name.
3235 * To do this we iterate over 0..num_cores to find a
3236 * non-existing core file name to use.
3238 if (indexpos != -1) {
3239 for (i = 0; i < num_cores; i++) {
3240 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3241 name[indexpos] = '0' + i;
3242 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3243 error = vn_open_cred(&nd, &flags, cmode, oflags,
3244 td->td_ucred, NULL);
3246 if (error == EEXIST)
3249 "pid %d (%s), uid (%u): Path `%s' failed "
3250 "on initial open test, error = %d\n",
3251 pid, comm, uid, name, error);
3257 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3258 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3259 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3263 audit_proc_coredump(td, name, error);
3268 NDFREE(&nd, NDF_ONLY_PNBUF);
3275 coredump_sanitise_path(const char *path)
3280 * Only send a subset of ASCII to devd(8) because it
3281 * might pass these strings to sh -c.
3283 for (i = 0; path[i]; i++)
3284 if (!(isalpha(path[i]) || isdigit(path[i])) &&
3285 path[i] != '/' && path[i] != '.' &&
3293 * Dump a process' core. The main routine does some
3294 * policy checking, and creates the name of the coredump;
3295 * then it passes on a vnode and a size limit to the process-specific
3296 * coredump routine if there is one; if there _is not_ one, it returns
3297 * ENOSYS; otherwise it returns the error from the process-specific routine.
3301 coredump(struct thread *td)
3303 struct proc *p = td->td_proc;
3304 struct ucred *cred = td->td_ucred;
3308 int error, error1, locked;
3309 char *name; /* name of corefile */
3313 char *fullpath, *freepath = NULL;
3315 static const char comm_name[] = "comm=";
3316 static const char core_name[] = "core=";
3318 PROC_LOCK_ASSERT(p, MA_OWNED);
3319 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3320 _STOPEVENT(p, S_CORE, 0);
3322 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3323 (p->p_flag2 & P2_NOTRACE) != 0) {
3329 * Note that the bulk of limit checking is done after
3330 * the corefile is created. The exception is if the limit
3331 * for corefiles is 0, in which case we don't bother
3332 * creating the corefile at all. This layout means that
3333 * a corefile is truncated instead of not being created,
3334 * if it is larger than the limit.
3336 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3337 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3343 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3344 compress_user_cores, &vp, &name);
3349 * Don't dump to non-regular files or files with links.
3350 * Do not dump into system files.
3352 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3353 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0) {
3361 /* Postpone other writers, including core dumps of other processes. */
3362 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3364 lf.l_whence = SEEK_SET;
3367 lf.l_type = F_WRLCK;
3368 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3372 if (set_core_nodump_flag)
3373 vattr.va_flags = UF_NODUMP;
3374 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3375 VOP_SETATTR(vp, &vattr, cred);
3378 p->p_acflag |= ACORE;
3381 if (p->p_sysent->sv_coredump != NULL) {
3382 error = p->p_sysent->sv_coredump(td, vp, limit,
3383 compress_user_cores ? IMGACT_CORE_COMPRESS : 0);
3389 lf.l_type = F_UNLCK;
3390 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3392 vn_rangelock_unlock(vp, rl_cookie);
3395 * Notify the userland helper that a process triggered a core dump.
3396 * This allows the helper to run an automated debugging session.
3398 if (error != 0 || coredump_devctl == 0)
3400 len = MAXPATHLEN * 2 + sizeof(comm_name) - 1 +
3401 sizeof(' ') + sizeof(core_name) - 1;
3402 data = malloc(len, M_TEMP, M_WAITOK);
3403 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3405 if (!coredump_sanitise_path(fullpath))
3407 snprintf(data, len, "%s%s ", comm_name, fullpath);
3408 free(freepath, M_TEMP);
3410 if (vn_fullpath_global(td, vp, &fullpath, &freepath) != 0)
3412 if (!coredump_sanitise_path(fullpath))
3414 strlcat(data, core_name, len);
3415 strlcat(data, fullpath, len);
3416 devctl_notify("kernel", "signal", "coredump", data);
3418 error1 = vn_close(vp, FWRITE, cred, td);
3422 audit_proc_coredump(td, name, error);
3424 free(freepath, M_TEMP);
3431 * Nonexistent system call-- signal process (may want to handle it). Flag
3432 * error in case process won't see signal immediately (blocked or ignored).
3434 #ifndef _SYS_SYSPROTO_H_
3443 struct nosys_args *args;
3445 struct proc *p = td->td_proc;
3448 tdsignal(td, SIGSYS);
3454 * Send a SIGIO or SIGURG signal to a process or process group using stored
3455 * credentials rather than those of the current process.
3458 pgsigio(sigiop, sig, checkctty)
3459 struct sigio **sigiop;
3463 struct sigio *sigio;
3465 ksiginfo_init(&ksi);
3466 ksi.ksi_signo = sig;
3467 ksi.ksi_code = SI_KERNEL;
3471 if (sigio == NULL) {
3475 if (sigio->sio_pgid > 0) {
3476 PROC_LOCK(sigio->sio_proc);
3477 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3478 kern_psignal(sigio->sio_proc, sig);
3479 PROC_UNLOCK(sigio->sio_proc);
3480 } else if (sigio->sio_pgid < 0) {
3483 PGRP_LOCK(sigio->sio_pgrp);
3484 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3486 if (p->p_state == PRS_NORMAL &&
3487 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3488 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3489 kern_psignal(p, sig);
3492 PGRP_UNLOCK(sigio->sio_pgrp);
3498 filt_sigattach(struct knote *kn)
3500 struct proc *p = curproc;
3502 kn->kn_ptr.p_proc = p;
3503 kn->kn_flags |= EV_CLEAR; /* automatically set */
3505 knlist_add(&p->p_klist, kn, 0);
3511 filt_sigdetach(struct knote *kn)
3513 struct proc *p = kn->kn_ptr.p_proc;
3515 knlist_remove(&p->p_klist, kn, 0);
3519 * signal knotes are shared with proc knotes, so we apply a mask to
3520 * the hint in order to differentiate them from process hints. This
3521 * could be avoided by using a signal-specific knote list, but probably
3522 * isn't worth the trouble.
3525 filt_signal(struct knote *kn, long hint)
3528 if (hint & NOTE_SIGNAL) {
3529 hint &= ~NOTE_SIGNAL;
3531 if (kn->kn_id == hint)
3534 return (kn->kn_data != 0);
3542 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3543 refcount_init(&ps->ps_refcnt, 1);
3544 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3549 sigacts_free(struct sigacts *ps)
3552 if (refcount_release(&ps->ps_refcnt) == 0)
3554 mtx_destroy(&ps->ps_mtx);
3555 free(ps, M_SUBPROC);
3559 sigacts_hold(struct sigacts *ps)
3562 refcount_acquire(&ps->ps_refcnt);
3567 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3570 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3571 mtx_lock(&src->ps_mtx);
3572 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3573 mtx_unlock(&src->ps_mtx);
3577 sigacts_shared(struct sigacts *ps)
3580 return (ps->ps_refcnt > 1);