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.
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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
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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
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34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
41 #include "opt_kdtrace.h"
42 #include "opt_ktrace.h"
44 #include "opt_procdesc.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/signalvar.h>
49 #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, kernel, , signal__send, "struct thread *",
98 "struct proc *", "int");
99 SDT_PROBE_DEFINE2(proc, kernel, , signal__clear, "int",
101 SDT_PROBE_DEFINE3(proc, kernel, , 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 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
143 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
144 &preallocate_siginfo, 0, "Preallocated signal memory size");
146 static int signal_overflow = 0;
147 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
148 &signal_overflow, 0, "Number of signals overflew");
150 static int signal_alloc_fail = 0;
151 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
152 &signal_alloc_fail, 0, "signals failed to be allocated");
154 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
157 * Policy -- Can ucred cr1 send SIGIO to process cr2?
158 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
159 * in the right situations.
161 #define CANSIGIO(cr1, cr2) \
162 ((cr1)->cr_uid == 0 || \
163 (cr1)->cr_ruid == (cr2)->cr_ruid || \
164 (cr1)->cr_uid == (cr2)->cr_ruid || \
165 (cr1)->cr_ruid == (cr2)->cr_uid || \
166 (cr1)->cr_uid == (cr2)->cr_uid)
168 static int sugid_coredump;
169 TUNABLE_INT("kern.sugid_coredump", &sugid_coredump);
170 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
171 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
173 static int capmode_coredump;
174 TUNABLE_INT("kern.capmode_coredump", &capmode_coredump);
175 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RW,
176 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
178 static int do_coredump = 1;
179 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
180 &do_coredump, 0, "Enable/Disable coredumps");
182 static int set_core_nodump_flag = 0;
183 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
184 0, "Enable setting the NODUMP flag on coredump files");
187 * Signal properties and actions.
188 * The array below categorizes the signals and their default actions
189 * according to the following properties:
191 #define SA_KILL 0x01 /* terminates process by default */
192 #define SA_CORE 0x02 /* ditto and coredumps */
193 #define SA_STOP 0x04 /* suspend process */
194 #define SA_TTYSTOP 0x08 /* ditto, from tty */
195 #define SA_IGNORE 0x10 /* ignore by default */
196 #define SA_CONT 0x20 /* continue if suspended */
197 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
199 static int sigproptbl[NSIG] = {
200 SA_KILL, /* SIGHUP */
201 SA_KILL, /* SIGINT */
202 SA_KILL|SA_CORE, /* SIGQUIT */
203 SA_KILL|SA_CORE, /* SIGILL */
204 SA_KILL|SA_CORE, /* SIGTRAP */
205 SA_KILL|SA_CORE, /* SIGABRT */
206 SA_KILL|SA_CORE, /* SIGEMT */
207 SA_KILL|SA_CORE, /* SIGFPE */
208 SA_KILL, /* SIGKILL */
209 SA_KILL|SA_CORE, /* SIGBUS */
210 SA_KILL|SA_CORE, /* SIGSEGV */
211 SA_KILL|SA_CORE, /* SIGSYS */
212 SA_KILL, /* SIGPIPE */
213 SA_KILL, /* SIGALRM */
214 SA_KILL, /* SIGTERM */
215 SA_IGNORE, /* SIGURG */
216 SA_STOP, /* SIGSTOP */
217 SA_STOP|SA_TTYSTOP, /* SIGTSTP */
218 SA_IGNORE|SA_CONT, /* SIGCONT */
219 SA_IGNORE, /* SIGCHLD */
220 SA_STOP|SA_TTYSTOP, /* SIGTTIN */
221 SA_STOP|SA_TTYSTOP, /* SIGTTOU */
222 SA_IGNORE, /* SIGIO */
223 SA_KILL, /* SIGXCPU */
224 SA_KILL, /* SIGXFSZ */
225 SA_KILL, /* SIGVTALRM */
226 SA_KILL, /* SIGPROF */
227 SA_IGNORE, /* SIGWINCH */
228 SA_IGNORE, /* SIGINFO */
229 SA_KILL, /* SIGUSR1 */
230 SA_KILL, /* SIGUSR2 */
233 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
238 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
239 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
240 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
241 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
242 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
243 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
247 ksiginfo_alloc(int wait)
254 if (ksiginfo_zone != NULL)
255 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
260 ksiginfo_free(ksiginfo_t *ksi)
262 uma_zfree(ksiginfo_zone, ksi);
266 ksiginfo_tryfree(ksiginfo_t *ksi)
268 if (!(ksi->ksi_flags & KSI_EXT)) {
269 uma_zfree(ksiginfo_zone, ksi);
276 sigqueue_init(sigqueue_t *list, struct proc *p)
278 SIGEMPTYSET(list->sq_signals);
279 SIGEMPTYSET(list->sq_kill);
280 TAILQ_INIT(&list->sq_list);
282 list->sq_flags = SQ_INIT;
286 * Get a signal's ksiginfo.
288 * 0 - signal not found
289 * others - signal number
292 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
294 struct proc *p = sq->sq_proc;
295 struct ksiginfo *ksi, *next;
298 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
300 if (!SIGISMEMBER(sq->sq_signals, signo))
303 if (SIGISMEMBER(sq->sq_kill, signo)) {
305 SIGDELSET(sq->sq_kill, signo);
308 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
309 if (ksi->ksi_signo == signo) {
311 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
312 ksi->ksi_sigq = NULL;
313 ksiginfo_copy(ksi, si);
314 if (ksiginfo_tryfree(ksi) && p != NULL)
323 SIGDELSET(sq->sq_signals, signo);
324 si->ksi_signo = signo;
329 sigqueue_take(ksiginfo_t *ksi)
335 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
339 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
340 ksi->ksi_sigq = NULL;
341 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
344 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
345 kp = TAILQ_NEXT(kp, ksi_link)) {
346 if (kp->ksi_signo == ksi->ksi_signo)
349 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
350 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
354 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
356 struct proc *p = sq->sq_proc;
357 struct ksiginfo *ksi;
360 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
362 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
363 SIGADDSET(sq->sq_kill, signo);
367 /* directly insert the ksi, don't copy it */
368 if (si->ksi_flags & KSI_INS) {
369 if (si->ksi_flags & KSI_HEAD)
370 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
372 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
377 if (__predict_false(ksiginfo_zone == NULL)) {
378 SIGADDSET(sq->sq_kill, signo);
382 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
385 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
391 ksiginfo_copy(si, ksi);
392 ksi->ksi_signo = signo;
393 if (si->ksi_flags & KSI_HEAD)
394 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
396 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
400 if ((si->ksi_flags & KSI_TRAP) != 0 ||
401 (si->ksi_flags & KSI_SIGQ) == 0) {
403 SIGADDSET(sq->sq_kill, signo);
412 SIGADDSET(sq->sq_signals, signo);
417 sigqueue_flush(sigqueue_t *sq)
419 struct proc *p = sq->sq_proc;
422 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
425 PROC_LOCK_ASSERT(p, MA_OWNED);
427 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
428 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
429 ksi->ksi_sigq = NULL;
430 if (ksiginfo_tryfree(ksi) && p != NULL)
434 SIGEMPTYSET(sq->sq_signals);
435 SIGEMPTYSET(sq->sq_kill);
439 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
442 struct proc *p1, *p2;
443 ksiginfo_t *ksi, *next;
445 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
446 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
449 /* Move siginfo to target list */
450 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
451 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
452 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
455 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
462 /* Move pending bits to target list */
464 SIGSETAND(tmp, *set);
465 SIGSETOR(dst->sq_kill, tmp);
466 SIGSETNAND(src->sq_kill, tmp);
468 tmp = src->sq_signals;
469 SIGSETAND(tmp, *set);
470 SIGSETOR(dst->sq_signals, tmp);
471 SIGSETNAND(src->sq_signals, tmp);
476 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
481 SIGADDSET(set, signo);
482 sigqueue_move_set(src, dst, &set);
487 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
489 struct proc *p = sq->sq_proc;
490 ksiginfo_t *ksi, *next;
492 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
494 /* Remove siginfo queue */
495 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
496 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
497 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
498 ksi->ksi_sigq = NULL;
499 if (ksiginfo_tryfree(ksi) && p != NULL)
503 SIGSETNAND(sq->sq_kill, *set);
504 SIGSETNAND(sq->sq_signals, *set);
508 sigqueue_delete(sigqueue_t *sq, int signo)
513 SIGADDSET(set, signo);
514 sigqueue_delete_set(sq, &set);
517 /* Remove a set of signals for a process */
519 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
524 PROC_LOCK_ASSERT(p, MA_OWNED);
526 sigqueue_init(&worklist, NULL);
527 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
529 FOREACH_THREAD_IN_PROC(p, td0)
530 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
532 sigqueue_flush(&worklist);
536 sigqueue_delete_proc(struct proc *p, int signo)
541 SIGADDSET(set, signo);
542 sigqueue_delete_set_proc(p, &set);
546 sigqueue_delete_stopmask_proc(struct proc *p)
551 SIGADDSET(set, SIGSTOP);
552 SIGADDSET(set, SIGTSTP);
553 SIGADDSET(set, SIGTTIN);
554 SIGADDSET(set, SIGTTOU);
555 sigqueue_delete_set_proc(p, &set);
559 * Determine signal that should be delivered to thread td, the current
560 * thread, 0 if none. If there is a pending stop signal with default
561 * action, the process stops in issignal().
564 cursig(struct thread *td)
566 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
567 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
568 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
569 return (SIGPENDING(td) ? issignal(td) : 0);
573 * Arrange for ast() to handle unmasked pending signals on return to user
574 * mode. This must be called whenever a signal is added to td_sigqueue or
575 * unmasked in td_sigmask.
578 signotify(struct thread *td)
584 PROC_LOCK_ASSERT(p, MA_OWNED);
586 if (SIGPENDING(td)) {
588 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
594 sigonstack(size_t sp)
596 struct thread *td = curthread;
598 return ((td->td_pflags & TDP_ALTSTACK) ?
599 #if defined(COMPAT_43)
600 ((td->td_sigstk.ss_size == 0) ?
601 (td->td_sigstk.ss_flags & SS_ONSTACK) :
602 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
604 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
613 if (sig > 0 && sig < NSIG)
614 return (sigproptbl[_SIG_IDX(sig)]);
619 sig_ffs(sigset_t *set)
623 for (i = 0; i < _SIG_WORDS; i++)
625 return (ffs(set->__bits[i]) + (i * 32));
630 sigact_flag_test(struct sigaction *act, int flag)
634 * SA_SIGINFO is reset when signal disposition is set to
635 * ignore or default. Other flags are kept according to user
638 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
639 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
640 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
650 kern_sigaction(td, sig, act, oact, flags)
653 struct sigaction *act, *oact;
657 struct proc *p = td->td_proc;
659 if (!_SIG_VALID(sig))
661 if (act != NULL && act->sa_handler != SIG_DFL &&
662 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
663 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
664 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
669 mtx_lock(&ps->ps_mtx);
671 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
673 if (SIGISMEMBER(ps->ps_sigonstack, sig))
674 oact->sa_flags |= SA_ONSTACK;
675 if (!SIGISMEMBER(ps->ps_sigintr, sig))
676 oact->sa_flags |= SA_RESTART;
677 if (SIGISMEMBER(ps->ps_sigreset, sig))
678 oact->sa_flags |= SA_RESETHAND;
679 if (SIGISMEMBER(ps->ps_signodefer, sig))
680 oact->sa_flags |= SA_NODEFER;
681 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
682 oact->sa_flags |= SA_SIGINFO;
684 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
686 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
687 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
688 oact->sa_flags |= SA_NOCLDSTOP;
689 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
690 oact->sa_flags |= SA_NOCLDWAIT;
693 if ((sig == SIGKILL || sig == SIGSTOP) &&
694 act->sa_handler != SIG_DFL) {
695 mtx_unlock(&ps->ps_mtx);
701 * Change setting atomically.
704 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
705 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
706 if (sigact_flag_test(act, SA_SIGINFO)) {
707 ps->ps_sigact[_SIG_IDX(sig)] =
708 (__sighandler_t *)act->sa_sigaction;
709 SIGADDSET(ps->ps_siginfo, sig);
711 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
712 SIGDELSET(ps->ps_siginfo, sig);
714 if (!sigact_flag_test(act, SA_RESTART))
715 SIGADDSET(ps->ps_sigintr, sig);
717 SIGDELSET(ps->ps_sigintr, sig);
718 if (sigact_flag_test(act, SA_ONSTACK))
719 SIGADDSET(ps->ps_sigonstack, sig);
721 SIGDELSET(ps->ps_sigonstack, sig);
722 if (sigact_flag_test(act, SA_RESETHAND))
723 SIGADDSET(ps->ps_sigreset, sig);
725 SIGDELSET(ps->ps_sigreset, sig);
726 if (sigact_flag_test(act, SA_NODEFER))
727 SIGADDSET(ps->ps_signodefer, sig);
729 SIGDELSET(ps->ps_signodefer, sig);
730 if (sig == SIGCHLD) {
731 if (act->sa_flags & SA_NOCLDSTOP)
732 ps->ps_flag |= PS_NOCLDSTOP;
734 ps->ps_flag &= ~PS_NOCLDSTOP;
735 if (act->sa_flags & SA_NOCLDWAIT) {
737 * Paranoia: since SA_NOCLDWAIT is implemented
738 * by reparenting the dying child to PID 1 (and
739 * trust it to reap the zombie), PID 1 itself
740 * is forbidden to set SA_NOCLDWAIT.
743 ps->ps_flag &= ~PS_NOCLDWAIT;
745 ps->ps_flag |= PS_NOCLDWAIT;
747 ps->ps_flag &= ~PS_NOCLDWAIT;
748 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
749 ps->ps_flag |= PS_CLDSIGIGN;
751 ps->ps_flag &= ~PS_CLDSIGIGN;
754 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
755 * and for signals set to SIG_DFL where the default is to
756 * ignore. However, don't put SIGCONT in ps_sigignore, as we
757 * have to restart the process.
759 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
760 (sigprop(sig) & SA_IGNORE &&
761 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
762 /* never to be seen again */
763 sigqueue_delete_proc(p, sig);
765 /* easier in psignal */
766 SIGADDSET(ps->ps_sigignore, sig);
767 SIGDELSET(ps->ps_sigcatch, sig);
769 SIGDELSET(ps->ps_sigignore, sig);
770 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
771 SIGDELSET(ps->ps_sigcatch, sig);
773 SIGADDSET(ps->ps_sigcatch, sig);
775 #ifdef COMPAT_FREEBSD4
776 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
777 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
778 (flags & KSA_FREEBSD4) == 0)
779 SIGDELSET(ps->ps_freebsd4, sig);
781 SIGADDSET(ps->ps_freebsd4, sig);
784 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
785 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
786 (flags & KSA_OSIGSET) == 0)
787 SIGDELSET(ps->ps_osigset, sig);
789 SIGADDSET(ps->ps_osigset, sig);
792 mtx_unlock(&ps->ps_mtx);
797 #ifndef _SYS_SYSPROTO_H_
798 struct sigaction_args {
800 struct sigaction *act;
801 struct sigaction *oact;
805 sys_sigaction(td, uap)
807 register struct sigaction_args *uap;
809 struct sigaction act, oact;
810 register struct sigaction *actp, *oactp;
813 actp = (uap->act != NULL) ? &act : NULL;
814 oactp = (uap->oact != NULL) ? &oact : NULL;
816 error = copyin(uap->act, actp, sizeof(act));
820 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
822 error = copyout(oactp, uap->oact, sizeof(oact));
826 #ifdef COMPAT_FREEBSD4
827 #ifndef _SYS_SYSPROTO_H_
828 struct freebsd4_sigaction_args {
830 struct sigaction *act;
831 struct sigaction *oact;
835 freebsd4_sigaction(td, uap)
837 register struct freebsd4_sigaction_args *uap;
839 struct sigaction act, oact;
840 register struct sigaction *actp, *oactp;
844 actp = (uap->act != NULL) ? &act : NULL;
845 oactp = (uap->oact != NULL) ? &oact : NULL;
847 error = copyin(uap->act, actp, sizeof(act));
851 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
853 error = copyout(oactp, uap->oact, sizeof(oact));
856 #endif /* COMAPT_FREEBSD4 */
858 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
859 #ifndef _SYS_SYSPROTO_H_
860 struct osigaction_args {
862 struct osigaction *nsa;
863 struct osigaction *osa;
869 register struct osigaction_args *uap;
871 struct osigaction sa;
872 struct sigaction nsa, osa;
873 register struct sigaction *nsap, *osap;
876 if (uap->signum <= 0 || uap->signum >= ONSIG)
879 nsap = (uap->nsa != NULL) ? &nsa : NULL;
880 osap = (uap->osa != NULL) ? &osa : NULL;
883 error = copyin(uap->nsa, &sa, sizeof(sa));
886 nsap->sa_handler = sa.sa_handler;
887 nsap->sa_flags = sa.sa_flags;
888 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
890 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
891 if (osap && !error) {
892 sa.sa_handler = osap->sa_handler;
893 sa.sa_flags = osap->sa_flags;
894 SIG2OSIG(osap->sa_mask, sa.sa_mask);
895 error = copyout(&sa, uap->osa, sizeof(sa));
900 #if !defined(__i386__)
901 /* Avoid replicating the same stub everywhere */
905 struct osigreturn_args *uap;
908 return (nosys(td, (struct nosys_args *)uap));
911 #endif /* COMPAT_43 */
914 * Initialize signal state for process 0;
915 * set to ignore signals that are ignored by default.
926 mtx_lock(&ps->ps_mtx);
927 for (i = 1; i <= NSIG; i++) {
928 if (sigprop(i) & SA_IGNORE && i != SIGCONT) {
929 SIGADDSET(ps->ps_sigignore, i);
932 mtx_unlock(&ps->ps_mtx);
937 * Reset specified signal to the default disposition.
940 sigdflt(struct sigacts *ps, int sig)
943 mtx_assert(&ps->ps_mtx, MA_OWNED);
944 SIGDELSET(ps->ps_sigcatch, sig);
945 if ((sigprop(sig) & SA_IGNORE) != 0 && sig != SIGCONT)
946 SIGADDSET(ps->ps_sigignore, sig);
947 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
948 SIGDELSET(ps->ps_siginfo, sig);
952 * Reset signals for an exec of the specified process.
955 execsigs(struct proc *p)
962 * Reset caught signals. Held signals remain held
963 * through td_sigmask (unless they were caught,
964 * and are now ignored by default).
966 PROC_LOCK_ASSERT(p, MA_OWNED);
967 td = FIRST_THREAD_IN_PROC(p);
969 mtx_lock(&ps->ps_mtx);
970 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
971 sig = sig_ffs(&ps->ps_sigcatch);
973 if ((sigprop(sig) & SA_IGNORE) != 0)
974 sigqueue_delete_proc(p, sig);
977 * Reset stack state to the user stack.
978 * Clear set of signals caught on the signal stack.
980 td->td_sigstk.ss_flags = SS_DISABLE;
981 td->td_sigstk.ss_size = 0;
982 td->td_sigstk.ss_sp = 0;
983 td->td_pflags &= ~TDP_ALTSTACK;
985 * Reset no zombies if child dies flag as Solaris does.
987 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
988 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
989 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
990 mtx_unlock(&ps->ps_mtx);
996 * Manipulate signal mask.
999 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1002 sigset_t new_block, oset1;
1007 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1008 PROC_LOCK_ASSERT(p, MA_OWNED);
1011 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1012 ? MA_OWNED : MA_NOTOWNED);
1014 *oset = td->td_sigmask;
1021 oset1 = td->td_sigmask;
1022 SIGSETOR(td->td_sigmask, *set);
1023 new_block = td->td_sigmask;
1024 SIGSETNAND(new_block, oset1);
1027 SIGSETNAND(td->td_sigmask, *set);
1032 oset1 = td->td_sigmask;
1033 if (flags & SIGPROCMASK_OLD)
1034 SIGSETLO(td->td_sigmask, *set);
1036 td->td_sigmask = *set;
1037 new_block = td->td_sigmask;
1038 SIGSETNAND(new_block, oset1);
1047 * The new_block set contains signals that were not previously
1048 * blocked, but are blocked now.
1050 * In case we block any signal that was not previously blocked
1051 * for td, and process has the signal pending, try to schedule
1052 * signal delivery to some thread that does not block the
1053 * signal, possibly waking it up.
1055 if (p->p_numthreads != 1)
1056 reschedule_signals(p, new_block, flags);
1060 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1065 #ifndef _SYS_SYSPROTO_H_
1066 struct sigprocmask_args {
1068 const sigset_t *set;
1073 sys_sigprocmask(td, uap)
1074 register struct thread *td;
1075 struct sigprocmask_args *uap;
1078 sigset_t *setp, *osetp;
1081 setp = (uap->set != NULL) ? &set : NULL;
1082 osetp = (uap->oset != NULL) ? &oset : NULL;
1084 error = copyin(uap->set, setp, sizeof(set));
1088 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1089 if (osetp && !error) {
1090 error = copyout(osetp, uap->oset, sizeof(oset));
1095 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1096 #ifndef _SYS_SYSPROTO_H_
1097 struct osigprocmask_args {
1103 osigprocmask(td, uap)
1104 register struct thread *td;
1105 struct osigprocmask_args *uap;
1110 OSIG2SIG(uap->mask, set);
1111 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1112 SIG2OSIG(oset, td->td_retval[0]);
1115 #endif /* COMPAT_43 */
1118 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1124 error = copyin(uap->set, &set, sizeof(set));
1126 td->td_retval[0] = error;
1130 error = kern_sigtimedwait(td, set, &ksi, NULL);
1132 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1134 if (error == ERESTART)
1136 td->td_retval[0] = error;
1140 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1141 td->td_retval[0] = error;
1146 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1149 struct timespec *timeout;
1155 error = copyin(uap->timeout, &ts, sizeof(ts));
1163 error = copyin(uap->set, &set, sizeof(set));
1167 error = kern_sigtimedwait(td, set, &ksi, timeout);
1172 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1175 td->td_retval[0] = ksi.ksi_signo;
1180 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1186 error = copyin(uap->set, &set, sizeof(set));
1190 error = kern_sigtimedwait(td, set, &ksi, NULL);
1195 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1198 td->td_retval[0] = ksi.ksi_signo;
1203 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1204 struct timespec *timeout)
1207 sigset_t saved_mask, new_block;
1209 int error, sig, timo, timevalid = 0;
1210 struct timespec rts, ets, ts;
1218 if (timeout != NULL) {
1219 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1221 getnanouptime(&rts);
1223 timespecadd(&ets, timeout);
1227 /* Some signals can not be waited for. */
1228 SIG_CANTMASK(waitset);
1231 saved_mask = td->td_sigmask;
1232 SIGSETNAND(td->td_sigmask, waitset);
1234 mtx_lock(&ps->ps_mtx);
1236 mtx_unlock(&ps->ps_mtx);
1237 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1238 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1239 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1249 * POSIX says this must be checked after looking for pending
1252 if (timeout != NULL) {
1257 getnanouptime(&rts);
1258 if (timespeccmp(&rts, &ets, >=)) {
1263 timespecsub(&ts, &rts);
1264 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1270 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1272 if (timeout != NULL) {
1273 if (error == ERESTART) {
1274 /* Timeout can not be restarted. */
1276 } else if (error == EAGAIN) {
1277 /* We will calculate timeout by ourself. */
1283 new_block = saved_mask;
1284 SIGSETNAND(new_block, td->td_sigmask);
1285 td->td_sigmask = saved_mask;
1287 * Fewer signals can be delivered to us, reschedule signal
1290 if (p->p_numthreads != 1)
1291 reschedule_signals(p, new_block, 0);
1294 SDT_PROBE2(proc, kernel, , signal__clear, sig, ksi);
1296 if (ksi->ksi_code == SI_TIMER)
1297 itimer_accept(p, ksi->ksi_timerid, ksi);
1300 if (KTRPOINT(td, KTR_PSIG)) {
1303 mtx_lock(&ps->ps_mtx);
1304 action = ps->ps_sigact[_SIG_IDX(sig)];
1305 mtx_unlock(&ps->ps_mtx);
1306 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1316 #ifndef _SYS_SYSPROTO_H_
1317 struct sigpending_args {
1322 sys_sigpending(td, uap)
1324 struct sigpending_args *uap;
1326 struct proc *p = td->td_proc;
1330 pending = p->p_sigqueue.sq_signals;
1331 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1333 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1336 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1337 #ifndef _SYS_SYSPROTO_H_
1338 struct osigpending_args {
1343 osigpending(td, uap)
1345 struct osigpending_args *uap;
1347 struct proc *p = td->td_proc;
1351 pending = p->p_sigqueue.sq_signals;
1352 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1354 SIG2OSIG(pending, td->td_retval[0]);
1357 #endif /* COMPAT_43 */
1359 #if defined(COMPAT_43)
1361 * Generalized interface signal handler, 4.3-compatible.
1363 #ifndef _SYS_SYSPROTO_H_
1364 struct osigvec_args {
1374 register struct osigvec_args *uap;
1377 struct sigaction nsa, osa;
1378 register struct sigaction *nsap, *osap;
1381 if (uap->signum <= 0 || uap->signum >= ONSIG)
1383 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1384 osap = (uap->osv != NULL) ? &osa : NULL;
1386 error = copyin(uap->nsv, &vec, sizeof(vec));
1389 nsap->sa_handler = vec.sv_handler;
1390 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1391 nsap->sa_flags = vec.sv_flags;
1392 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1394 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1395 if (osap && !error) {
1396 vec.sv_handler = osap->sa_handler;
1397 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1398 vec.sv_flags = osap->sa_flags;
1399 vec.sv_flags &= ~SA_NOCLDWAIT;
1400 vec.sv_flags ^= SA_RESTART;
1401 error = copyout(&vec, uap->osv, sizeof(vec));
1406 #ifndef _SYS_SYSPROTO_H_
1407 struct osigblock_args {
1413 register struct thread *td;
1414 struct osigblock_args *uap;
1418 OSIG2SIG(uap->mask, set);
1419 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1420 SIG2OSIG(oset, td->td_retval[0]);
1424 #ifndef _SYS_SYSPROTO_H_
1425 struct osigsetmask_args {
1430 osigsetmask(td, uap)
1432 struct osigsetmask_args *uap;
1436 OSIG2SIG(uap->mask, set);
1437 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1438 SIG2OSIG(oset, td->td_retval[0]);
1441 #endif /* COMPAT_43 */
1444 * Suspend calling thread until signal, providing mask to be set in the
1447 #ifndef _SYS_SYSPROTO_H_
1448 struct sigsuspend_args {
1449 const sigset_t *sigmask;
1454 sys_sigsuspend(td, uap)
1456 struct sigsuspend_args *uap;
1461 error = copyin(uap->sigmask, &mask, sizeof(mask));
1464 return (kern_sigsuspend(td, mask));
1468 kern_sigsuspend(struct thread *td, sigset_t mask)
1470 struct proc *p = td->td_proc;
1474 * When returning from sigsuspend, we want
1475 * the old mask to be restored after the
1476 * signal handler has finished. Thus, we
1477 * save it here and mark the sigacts structure
1481 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1482 SIGPROCMASK_PROC_LOCKED);
1483 td->td_pflags |= TDP_OLDMASK;
1486 * Process signals now. Otherwise, we can get spurious wakeup
1487 * due to signal entered process queue, but delivered to other
1488 * thread. But sigsuspend should return only on signal
1491 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1492 for (has_sig = 0; !has_sig;) {
1493 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1496 thread_suspend_check(0);
1497 mtx_lock(&p->p_sigacts->ps_mtx);
1498 while ((sig = cursig(td)) != 0)
1499 has_sig += postsig(sig);
1500 mtx_unlock(&p->p_sigacts->ps_mtx);
1503 td->td_errno = EINTR;
1504 td->td_pflags |= TDP_NERRNO;
1505 return (EJUSTRETURN);
1508 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1510 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1511 * convention: libc stub passes mask, not pointer, to save a copyin.
1513 #ifndef _SYS_SYSPROTO_H_
1514 struct osigsuspend_args {
1520 osigsuspend(td, uap)
1522 struct osigsuspend_args *uap;
1526 OSIG2SIG(uap->mask, mask);
1527 return (kern_sigsuspend(td, mask));
1529 #endif /* COMPAT_43 */
1531 #if defined(COMPAT_43)
1532 #ifndef _SYS_SYSPROTO_H_
1533 struct osigstack_args {
1534 struct sigstack *nss;
1535 struct sigstack *oss;
1542 register struct osigstack_args *uap;
1544 struct sigstack nss, oss;
1547 if (uap->nss != NULL) {
1548 error = copyin(uap->nss, &nss, sizeof(nss));
1552 oss.ss_sp = td->td_sigstk.ss_sp;
1553 oss.ss_onstack = sigonstack(cpu_getstack(td));
1554 if (uap->nss != NULL) {
1555 td->td_sigstk.ss_sp = nss.ss_sp;
1556 td->td_sigstk.ss_size = 0;
1557 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1558 td->td_pflags |= TDP_ALTSTACK;
1560 if (uap->oss != NULL)
1561 error = copyout(&oss, uap->oss, sizeof(oss));
1565 #endif /* COMPAT_43 */
1567 #ifndef _SYS_SYSPROTO_H_
1568 struct sigaltstack_args {
1575 sys_sigaltstack(td, uap)
1577 register struct sigaltstack_args *uap;
1582 if (uap->ss != NULL) {
1583 error = copyin(uap->ss, &ss, sizeof(ss));
1587 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1588 (uap->oss != NULL) ? &oss : NULL);
1591 if (uap->oss != NULL)
1592 error = copyout(&oss, uap->oss, sizeof(stack_t));
1597 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1599 struct proc *p = td->td_proc;
1602 oonstack = sigonstack(cpu_getstack(td));
1605 *oss = td->td_sigstk;
1606 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1607 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1613 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1615 if (!(ss->ss_flags & SS_DISABLE)) {
1616 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1619 td->td_sigstk = *ss;
1620 td->td_pflags |= TDP_ALTSTACK;
1622 td->td_pflags &= ~TDP_ALTSTACK;
1629 * Common code for kill process group/broadcast kill.
1630 * cp is calling process.
1633 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1645 sx_slock(&allproc_lock);
1646 FOREACH_PROC_IN_SYSTEM(p) {
1648 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1649 p == td->td_proc || p->p_state == PRS_NEW) {
1653 err = p_cansignal(td, p, sig);
1656 pksignal(p, sig, ksi);
1659 else if (ret == ESRCH)
1663 sx_sunlock(&allproc_lock);
1665 sx_slock(&proctree_lock);
1668 * zero pgid means send to my process group.
1670 pgrp = td->td_proc->p_pgrp;
1673 pgrp = pgfind(pgid);
1675 sx_sunlock(&proctree_lock);
1679 sx_sunlock(&proctree_lock);
1680 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1682 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1683 p->p_state == PRS_NEW) {
1687 err = p_cansignal(td, p, sig);
1690 pksignal(p, sig, ksi);
1693 else if (ret == ESRCH)
1702 #ifndef _SYS_SYSPROTO_H_
1710 sys_kill(struct thread *td, struct kill_args *uap)
1717 * A process in capability mode can send signals only to himself.
1718 * The main rationale behind this is that abort(3) is implemented as
1719 * kill(getpid(), SIGABRT).
1721 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1724 AUDIT_ARG_SIGNUM(uap->signum);
1725 AUDIT_ARG_PID(uap->pid);
1726 if ((u_int)uap->signum > _SIG_MAXSIG)
1729 ksiginfo_init(&ksi);
1730 ksi.ksi_signo = uap->signum;
1731 ksi.ksi_code = SI_USER;
1732 ksi.ksi_pid = td->td_proc->p_pid;
1733 ksi.ksi_uid = td->td_ucred->cr_ruid;
1736 /* kill single process */
1737 if ((p = pfind(uap->pid)) == NULL) {
1738 if ((p = zpfind(uap->pid)) == NULL)
1741 AUDIT_ARG_PROCESS(p);
1742 error = p_cansignal(td, p, uap->signum);
1743 if (error == 0 && uap->signum)
1744 pksignal(p, uap->signum, &ksi);
1749 case -1: /* broadcast signal */
1750 return (killpg1(td, uap->signum, 0, 1, &ksi));
1751 case 0: /* signal own process group */
1752 return (killpg1(td, uap->signum, 0, 0, &ksi));
1753 default: /* negative explicit process group */
1754 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1762 struct pdkill_args *uap;
1766 cap_rights_t rights;
1769 AUDIT_ARG_SIGNUM(uap->signum);
1770 AUDIT_ARG_FD(uap->fd);
1771 if ((u_int)uap->signum > _SIG_MAXSIG)
1774 error = procdesc_find(td, uap->fd,
1775 cap_rights_init(&rights, CAP_PDKILL), &p);
1778 AUDIT_ARG_PROCESS(p);
1779 error = p_cansignal(td, p, uap->signum);
1780 if (error == 0 && uap->signum)
1781 kern_psignal(p, uap->signum);
1789 #if defined(COMPAT_43)
1790 #ifndef _SYS_SYSPROTO_H_
1791 struct okillpg_args {
1798 okillpg(struct thread *td, struct okillpg_args *uap)
1802 AUDIT_ARG_SIGNUM(uap->signum);
1803 AUDIT_ARG_PID(uap->pgid);
1804 if ((u_int)uap->signum > _SIG_MAXSIG)
1807 ksiginfo_init(&ksi);
1808 ksi.ksi_signo = uap->signum;
1809 ksi.ksi_code = SI_USER;
1810 ksi.ksi_pid = td->td_proc->p_pid;
1811 ksi.ksi_uid = td->td_ucred->cr_ruid;
1812 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1814 #endif /* COMPAT_43 */
1816 #ifndef _SYS_SYSPROTO_H_
1817 struct sigqueue_args {
1820 /* union sigval */ void *value;
1824 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1830 if ((u_int)uap->signum > _SIG_MAXSIG)
1834 * Specification says sigqueue can only send signal to
1840 if ((p = pfind(uap->pid)) == NULL) {
1841 if ((p = zpfind(uap->pid)) == NULL)
1844 error = p_cansignal(td, p, uap->signum);
1845 if (error == 0 && uap->signum != 0) {
1846 ksiginfo_init(&ksi);
1847 ksi.ksi_flags = KSI_SIGQ;
1848 ksi.ksi_signo = uap->signum;
1849 ksi.ksi_code = SI_QUEUE;
1850 ksi.ksi_pid = td->td_proc->p_pid;
1851 ksi.ksi_uid = td->td_ucred->cr_ruid;
1852 ksi.ksi_value.sival_ptr = uap->value;
1853 error = pksignal(p, ksi.ksi_signo, &ksi);
1860 * Send a signal to a process group.
1863 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1868 sx_slock(&proctree_lock);
1869 pgrp = pgfind(pgid);
1870 sx_sunlock(&proctree_lock);
1872 pgsignal(pgrp, sig, 0, ksi);
1879 * Send a signal to a process group. If checktty is 1,
1880 * limit to members which have a controlling terminal.
1883 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1888 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1889 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1891 if (p->p_state == PRS_NORMAL &&
1892 (checkctty == 0 || p->p_flag & P_CONTROLT))
1893 pksignal(p, sig, ksi);
1901 * Recalculate the signal mask and reset the signal disposition after
1902 * usermode frame for delivery is formed. Should be called after
1903 * mach-specific routine, because sysent->sv_sendsig() needs correct
1904 * ps_siginfo and signal mask.
1907 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1911 mtx_assert(&ps->ps_mtx, MA_OWNED);
1912 td->td_ru.ru_nsignals++;
1913 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1914 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1915 SIGADDSET(mask, sig);
1916 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1917 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1918 if (SIGISMEMBER(ps->ps_sigreset, sig))
1924 * Send a signal caused by a trap to the current thread. If it will be
1925 * caught immediately, deliver it with correct code. Otherwise, post it
1929 trapsignal(struct thread *td, ksiginfo_t *ksi)
1937 sig = ksi->ksi_signo;
1938 code = ksi->ksi_code;
1939 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1943 mtx_lock(&ps->ps_mtx);
1944 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1945 !SIGISMEMBER(td->td_sigmask, sig)) {
1947 if (KTRPOINT(curthread, KTR_PSIG))
1948 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1949 &td->td_sigmask, code);
1951 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1952 ksi, &td->td_sigmask);
1953 postsig_done(sig, td, ps);
1954 mtx_unlock(&ps->ps_mtx);
1957 * Avoid a possible infinite loop if the thread
1958 * masking the signal or process is ignoring the
1961 if (kern_forcesigexit &&
1962 (SIGISMEMBER(td->td_sigmask, sig) ||
1963 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1964 SIGDELSET(td->td_sigmask, sig);
1965 SIGDELSET(ps->ps_sigcatch, sig);
1966 SIGDELSET(ps->ps_sigignore, sig);
1967 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1969 mtx_unlock(&ps->ps_mtx);
1970 p->p_code = code; /* XXX for core dump/debugger */
1971 p->p_sig = sig; /* XXX to verify code */
1972 tdsendsignal(p, td, sig, ksi);
1977 static struct thread *
1978 sigtd(struct proc *p, int sig, int prop)
1980 struct thread *td, *signal_td;
1982 PROC_LOCK_ASSERT(p, MA_OWNED);
1985 * Check if current thread can handle the signal without
1986 * switching context to another thread.
1988 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1991 FOREACH_THREAD_IN_PROC(p, td) {
1992 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1997 if (signal_td == NULL)
1998 signal_td = FIRST_THREAD_IN_PROC(p);
2003 * Send the signal to the process. If the signal has an action, the action
2004 * is usually performed by the target process rather than the caller; we add
2005 * the signal to the set of pending signals for the process.
2008 * o When a stop signal is sent to a sleeping process that takes the
2009 * default action, the process is stopped without awakening it.
2010 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2011 * regardless of the signal action (eg, blocked or ignored).
2013 * Other ignored signals are discarded immediately.
2015 * NB: This function may be entered from the debugger via the "kill" DDB
2016 * command. There is little that can be done to mitigate the possibly messy
2017 * side effects of this unwise possibility.
2020 kern_psignal(struct proc *p, int sig)
2024 ksiginfo_init(&ksi);
2025 ksi.ksi_signo = sig;
2026 ksi.ksi_code = SI_KERNEL;
2027 (void) tdsendsignal(p, NULL, sig, &ksi);
2031 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2034 return (tdsendsignal(p, NULL, sig, ksi));
2037 /* Utility function for finding a thread to send signal event to. */
2039 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2043 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2044 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2056 tdsignal(struct thread *td, int sig)
2060 ksiginfo_init(&ksi);
2061 ksi.ksi_signo = sig;
2062 ksi.ksi_code = SI_KERNEL;
2063 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2067 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2070 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2074 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2077 sigqueue_t *sigqueue;
2084 MPASS(td == NULL || p == td->td_proc);
2085 PROC_LOCK_ASSERT(p, MA_OWNED);
2087 if (!_SIG_VALID(sig))
2088 panic("%s(): invalid signal %d", __func__, sig);
2090 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2093 * IEEE Std 1003.1-2001: return success when killing a zombie.
2095 if (p->p_state == PRS_ZOMBIE) {
2096 if (ksi && (ksi->ksi_flags & KSI_INS))
2097 ksiginfo_tryfree(ksi);
2102 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2103 prop = sigprop(sig);
2106 td = sigtd(p, sig, prop);
2107 sigqueue = &p->p_sigqueue;
2109 sigqueue = &td->td_sigqueue;
2111 SDT_PROBE3(proc, kernel, , signal__send, td, p, sig);
2114 * If the signal is being ignored,
2115 * then we forget about it immediately.
2116 * (Note: we don't set SIGCONT in ps_sigignore,
2117 * and if it is set to SIG_IGN,
2118 * action will be SIG_DFL here.)
2120 mtx_lock(&ps->ps_mtx);
2121 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2122 SDT_PROBE3(proc, kernel, , signal__discard, td, p, sig);
2124 mtx_unlock(&ps->ps_mtx);
2125 if (ksi && (ksi->ksi_flags & KSI_INS))
2126 ksiginfo_tryfree(ksi);
2129 if (SIGISMEMBER(td->td_sigmask, sig))
2131 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2135 if (SIGISMEMBER(ps->ps_sigintr, sig))
2139 mtx_unlock(&ps->ps_mtx);
2142 sigqueue_delete_stopmask_proc(p);
2143 else if (prop & SA_STOP) {
2145 * If sending a tty stop signal to a member of an orphaned
2146 * process group, discard the signal here if the action
2147 * is default; don't stop the process below if sleeping,
2148 * and don't clear any pending SIGCONT.
2150 if ((prop & SA_TTYSTOP) &&
2151 (p->p_pgrp->pg_jobc == 0) &&
2152 (action == SIG_DFL)) {
2153 if (ksi && (ksi->ksi_flags & KSI_INS))
2154 ksiginfo_tryfree(ksi);
2157 sigqueue_delete_proc(p, SIGCONT);
2158 if (p->p_flag & P_CONTINUED) {
2159 p->p_flag &= ~P_CONTINUED;
2160 PROC_LOCK(p->p_pptr);
2161 sigqueue_take(p->p_ksi);
2162 PROC_UNLOCK(p->p_pptr);
2166 ret = sigqueue_add(sigqueue, sig, ksi);
2171 * Defer further processing for signals which are held,
2172 * except that stopped processes must be continued by SIGCONT.
2174 if (action == SIG_HOLD &&
2175 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2178 * SIGKILL: Remove procfs STOPEVENTs.
2180 if (sig == SIGKILL) {
2181 /* from procfs_ioctl.c: PIOCBIC */
2183 /* from procfs_ioctl.c: PIOCCONT */
2188 * Some signals have a process-wide effect and a per-thread
2189 * component. Most processing occurs when the process next
2190 * tries to cross the user boundary, however there are some
2191 * times when processing needs to be done immediately, such as
2192 * waking up threads so that they can cross the user boundary.
2193 * We try to do the per-process part here.
2195 if (P_SHOULDSTOP(p)) {
2196 KASSERT(!(p->p_flag & P_WEXIT),
2197 ("signal to stopped but exiting process"));
2198 if (sig == SIGKILL) {
2200 * If traced process is already stopped,
2201 * then no further action is necessary.
2203 if (p->p_flag & P_TRACED)
2206 * SIGKILL sets process running.
2207 * It will die elsewhere.
2208 * All threads must be restarted.
2210 p->p_flag &= ~P_STOPPED_SIG;
2214 if (prop & SA_CONT) {
2216 * If traced process is already stopped,
2217 * then no further action is necessary.
2219 if (p->p_flag & P_TRACED)
2222 * If SIGCONT is default (or ignored), we continue the
2223 * process but don't leave the signal in sigqueue as
2224 * it has no further action. If SIGCONT is held, we
2225 * continue the process and leave the signal in
2226 * sigqueue. If the process catches SIGCONT, let it
2227 * handle the signal itself. If it isn't waiting on
2228 * an event, it goes back to run state.
2229 * Otherwise, process goes back to sleep state.
2231 p->p_flag &= ~P_STOPPED_SIG;
2233 if (p->p_numthreads == p->p_suspcount) {
2235 p->p_flag |= P_CONTINUED;
2236 p->p_xstat = SIGCONT;
2237 PROC_LOCK(p->p_pptr);
2238 childproc_continued(p);
2239 PROC_UNLOCK(p->p_pptr);
2242 if (action == SIG_DFL) {
2243 thread_unsuspend(p);
2245 sigqueue_delete(sigqueue, sig);
2248 if (action == SIG_CATCH) {
2250 * The process wants to catch it so it needs
2251 * to run at least one thread, but which one?
2257 * The signal is not ignored or caught.
2259 thread_unsuspend(p);
2264 if (prop & SA_STOP) {
2266 * If traced process is already stopped,
2267 * then no further action is necessary.
2269 if (p->p_flag & P_TRACED)
2272 * Already stopped, don't need to stop again
2273 * (If we did the shell could get confused).
2274 * Just make sure the signal STOP bit set.
2276 p->p_flag |= P_STOPPED_SIG;
2277 sigqueue_delete(sigqueue, sig);
2282 * All other kinds of signals:
2283 * If a thread is sleeping interruptibly, simulate a
2284 * wakeup so that when it is continued it will be made
2285 * runnable and can look at the signal. However, don't make
2286 * the PROCESS runnable, leave it stopped.
2287 * It may run a bit until it hits a thread_suspend_check().
2292 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2293 wakeup_swapper = sleepq_abort(td, intrval);
2300 * Mutexes are short lived. Threads waiting on them will
2301 * hit thread_suspend_check() soon.
2303 } else if (p->p_state == PRS_NORMAL) {
2304 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2305 tdsigwakeup(td, sig, action, intrval);
2309 MPASS(action == SIG_DFL);
2311 if (prop & SA_STOP) {
2312 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2314 p->p_flag |= P_STOPPED_SIG;
2317 sig_suspend_threads(td, p, 1);
2318 if (p->p_numthreads == p->p_suspcount) {
2320 * only thread sending signal to another
2321 * process can reach here, if thread is sending
2322 * signal to its process, because thread does
2323 * not suspend itself here, p_numthreads
2324 * should never be equal to p_suspcount.
2328 sigqueue_delete_proc(p, p->p_xstat);
2334 /* Not in "NORMAL" state. discard the signal. */
2335 sigqueue_delete(sigqueue, sig);
2340 * The process is not stopped so we need to apply the signal to all the
2344 tdsigwakeup(td, sig, action, intrval);
2346 thread_unsuspend(p);
2349 /* If we jump here, proc slock should not be owned. */
2350 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2355 * The force of a signal has been directed against a single
2356 * thread. We need to see what we can do about knocking it
2357 * out of any sleep it may be in etc.
2360 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2362 struct proc *p = td->td_proc;
2367 PROC_LOCK_ASSERT(p, MA_OWNED);
2368 prop = sigprop(sig);
2373 * Bring the priority of a thread up if we want it to get
2374 * killed in this lifetime. Be careful to avoid bumping the
2375 * priority of the idle thread, since we still allow to signal
2378 if (action == SIG_DFL && (prop & SA_KILL) != 0 &&
2379 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2380 sched_prio(td, PUSER);
2381 if (TD_ON_SLEEPQ(td)) {
2383 * If thread is sleeping uninterruptibly
2384 * we can't interrupt the sleep... the signal will
2385 * be noticed when the process returns through
2386 * trap() or syscall().
2388 if ((td->td_flags & TDF_SINTR) == 0)
2391 * If SIGCONT is default (or ignored) and process is
2392 * asleep, we are finished; the process should not
2395 if ((prop & SA_CONT) && action == SIG_DFL) {
2398 sigqueue_delete(&p->p_sigqueue, sig);
2400 * It may be on either list in this state.
2401 * Remove from both for now.
2403 sigqueue_delete(&td->td_sigqueue, sig);
2408 * Don't awaken a sleeping thread for SIGSTOP if the
2409 * STOP signal is deferred.
2411 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2415 * Give low priority threads a better chance to run.
2417 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2418 sched_prio(td, PUSER);
2420 wakeup_swapper = sleepq_abort(td, intrval);
2423 * Other states do nothing with the signal immediately,
2424 * other than kicking ourselves if we are running.
2425 * It will either never be noticed, or noticed very soon.
2428 if (TD_IS_RUNNING(td) && td != curthread)
2440 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2444 PROC_LOCK_ASSERT(p, MA_OWNED);
2445 PROC_SLOCK_ASSERT(p, MA_OWNED);
2447 FOREACH_THREAD_IN_PROC(p, td2) {
2449 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2450 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2451 (td2->td_flags & TDF_SINTR)) {
2452 if (td2->td_flags & TDF_SBDRY) {
2454 * Once a thread is asleep with
2455 * TDF_SBDRY set, it should never
2456 * become suspended due to this check.
2458 KASSERT(!TD_IS_SUSPENDED(td2),
2459 ("thread with deferred stops suspended"));
2460 } else if (!TD_IS_SUSPENDED(td2)) {
2461 thread_suspend_one(td2);
2463 } else if (!TD_IS_SUSPENDED(td2)) {
2464 if (sending || td != td2)
2465 td2->td_flags |= TDF_ASTPENDING;
2467 if (TD_IS_RUNNING(td2) && td2 != td)
2468 forward_signal(td2);
2476 ptracestop(struct thread *td, int sig)
2478 struct proc *p = td->td_proc;
2480 PROC_LOCK_ASSERT(p, MA_OWNED);
2481 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2482 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2483 &p->p_mtx.lock_object, "Stopping for traced signal");
2485 td->td_dbgflags |= TDB_XSIG;
2487 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2488 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2490 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2491 if (p->p_flag & P_SINGLE_EXIT) {
2492 td->td_dbgflags &= ~TDB_XSIG;
2497 * Just make wait() to work, the last stopped thread
2502 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2503 sig_suspend_threads(td, p, 0);
2504 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2505 td->td_dbgflags &= ~TDB_STOPATFORK;
2506 cv_broadcast(&p->p_dbgwait);
2509 thread_suspend_switch(td, p);
2510 if (p->p_xthread == td)
2511 p->p_xthread = NULL;
2512 if (!(p->p_flag & P_TRACED))
2514 if (td->td_dbgflags & TDB_SUSPEND) {
2515 if (p->p_flag & P_SINGLE_EXIT)
2521 return (td->td_xsig);
2525 reschedule_signals(struct proc *p, sigset_t block, int flags)
2531 PROC_LOCK_ASSERT(p, MA_OWNED);
2533 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2534 MA_OWNED : MA_NOTOWNED);
2535 if (SIGISEMPTY(p->p_siglist))
2537 SIGSETAND(block, p->p_siglist);
2538 while ((sig = sig_ffs(&block)) != 0) {
2539 SIGDELSET(block, sig);
2540 td = sigtd(p, sig, 0);
2542 if (!(flags & SIGPROCMASK_PS_LOCKED))
2543 mtx_lock(&ps->ps_mtx);
2544 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2545 tdsigwakeup(td, sig, SIG_CATCH,
2546 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2548 if (!(flags & SIGPROCMASK_PS_LOCKED))
2549 mtx_unlock(&ps->ps_mtx);
2554 tdsigcleanup(struct thread *td)
2560 PROC_LOCK_ASSERT(p, MA_OWNED);
2562 sigqueue_flush(&td->td_sigqueue);
2563 if (p->p_numthreads == 1)
2567 * Since we cannot handle signals, notify signal post code
2568 * about this by filling the sigmask.
2570 * Also, if needed, wake up thread(s) that do not block the
2571 * same signals as the exiting thread, since the thread might
2572 * have been selected for delivery and woken up.
2574 SIGFILLSET(unblocked);
2575 SIGSETNAND(unblocked, td->td_sigmask);
2576 SIGFILLSET(td->td_sigmask);
2577 reschedule_signals(p, unblocked, 0);
2582 * Defer the delivery of SIGSTOP for the current thread. Returns true
2583 * if stops were deferred and false if they were already deferred.
2591 if (td->td_flags & TDF_SBDRY)
2594 td->td_flags |= TDF_SBDRY;
2600 * Permit the delivery of SIGSTOP for the current thread. This does
2601 * not immediately suspend if a stop was posted. Instead, the thread
2602 * will suspend either via ast() or a subsequent interruptible sleep.
2612 prev = (td->td_flags & TDF_SBDRY) != 0;
2613 td->td_flags &= ~TDF_SBDRY;
2619 * If the current process has received a signal (should be caught or cause
2620 * termination, should interrupt current syscall), return the signal number.
2621 * Stop signals with default action are processed immediately, then cleared;
2622 * they aren't returned. This is checked after each entry to the system for
2623 * a syscall or trap (though this can usually be done without calling issignal
2624 * by checking the pending signal masks in cursig.) The normal call
2627 * while (sig = cursig(curthread))
2631 issignal(struct thread *td)
2635 struct sigqueue *queue;
2636 sigset_t sigpending;
2637 int sig, prop, newsig;
2641 mtx_assert(&ps->ps_mtx, MA_OWNED);
2642 PROC_LOCK_ASSERT(p, MA_OWNED);
2644 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2646 sigpending = td->td_sigqueue.sq_signals;
2647 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2648 SIGSETNAND(sigpending, td->td_sigmask);
2650 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2651 SIG_STOPSIGMASK(sigpending);
2652 if (SIGISEMPTY(sigpending)) /* no signal to send */
2654 sig = sig_ffs(&sigpending);
2656 if (p->p_stops & S_SIG) {
2657 mtx_unlock(&ps->ps_mtx);
2658 stopevent(p, S_SIG, sig);
2659 mtx_lock(&ps->ps_mtx);
2663 * We should see pending but ignored signals
2664 * only if P_TRACED was on when they were posted.
2666 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2667 sigqueue_delete(&td->td_sigqueue, sig);
2668 sigqueue_delete(&p->p_sigqueue, sig);
2671 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) {
2673 * If traced, always stop.
2674 * Remove old signal from queue before the stop.
2675 * XXX shrug off debugger, it causes siginfo to
2678 queue = &td->td_sigqueue;
2679 td->td_dbgksi.ksi_signo = 0;
2680 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2681 queue = &p->p_sigqueue;
2682 sigqueue_get(queue, sig, &td->td_dbgksi);
2685 mtx_unlock(&ps->ps_mtx);
2686 newsig = ptracestop(td, sig);
2687 mtx_lock(&ps->ps_mtx);
2689 if (sig != newsig) {
2692 * If parent wants us to take the signal,
2693 * then it will leave it in p->p_xstat;
2694 * otherwise we just look for signals again.
2701 * Put the new signal into td_sigqueue. If the
2702 * signal is being masked, look for other
2705 sigqueue_add(queue, sig, NULL);
2706 if (SIGISMEMBER(td->td_sigmask, sig))
2710 if (td->td_dbgksi.ksi_signo != 0) {
2711 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2712 if (sigqueue_add(&td->td_sigqueue, sig,
2713 &td->td_dbgksi) != 0)
2714 td->td_dbgksi.ksi_signo = 0;
2716 if (td->td_dbgksi.ksi_signo == 0)
2717 sigqueue_add(&td->td_sigqueue, sig,
2722 * If the traced bit got turned off, go back up
2723 * to the top to rescan signals. This ensures
2724 * that p_sig* and p_sigact are consistent.
2726 if ((p->p_flag & P_TRACED) == 0)
2730 prop = sigprop(sig);
2733 * Decide whether the signal should be returned.
2734 * Return the signal's number, or fall through
2735 * to clear it from the pending mask.
2737 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2739 case (intptr_t)SIG_DFL:
2741 * Don't take default actions on system processes.
2743 if (p->p_pid <= 1) {
2746 * Are you sure you want to ignore SIGSEGV
2749 printf("Process (pid %lu) got signal %d\n",
2750 (u_long)p->p_pid, sig);
2752 break; /* == ignore */
2755 * If there is a pending stop signal to process
2756 * with default action, stop here,
2757 * then clear the signal. However,
2758 * if process is member of an orphaned
2759 * process group, ignore tty stop signals.
2761 if (prop & SA_STOP) {
2762 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2763 (p->p_pgrp->pg_jobc == 0 &&
2765 break; /* == ignore */
2766 mtx_unlock(&ps->ps_mtx);
2767 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2768 &p->p_mtx.lock_object, "Catching SIGSTOP");
2769 p->p_flag |= P_STOPPED_SIG;
2772 sig_suspend_threads(td, p, 0);
2773 thread_suspend_switch(td, p);
2775 mtx_lock(&ps->ps_mtx);
2777 } else if (prop & SA_IGNORE) {
2779 * Except for SIGCONT, shouldn't get here.
2780 * Default action is to ignore; drop it.
2782 break; /* == ignore */
2787 case (intptr_t)SIG_IGN:
2789 * Masking above should prevent us ever trying
2790 * to take action on an ignored signal other
2791 * than SIGCONT, unless process is traced.
2793 if ((prop & SA_CONT) == 0 &&
2794 (p->p_flag & P_TRACED) == 0)
2795 printf("issignal\n");
2796 break; /* == ignore */
2800 * This signal has an action, let
2801 * postsig() process it.
2805 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2806 sigqueue_delete(&p->p_sigqueue, sig);
2812 thread_stopped(struct proc *p)
2816 PROC_LOCK_ASSERT(p, MA_OWNED);
2817 PROC_SLOCK_ASSERT(p, MA_OWNED);
2821 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2823 p->p_flag &= ~P_WAITED;
2824 PROC_LOCK(p->p_pptr);
2825 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2826 CLD_TRAPPED : CLD_STOPPED);
2827 PROC_UNLOCK(p->p_pptr);
2833 * Take the action for the specified signal
2834 * from the current set of pending signals.
2840 struct thread *td = curthread;
2841 register struct proc *p = td->td_proc;
2845 sigset_t returnmask;
2847 KASSERT(sig != 0, ("postsig"));
2849 PROC_LOCK_ASSERT(p, MA_OWNED);
2851 mtx_assert(&ps->ps_mtx, MA_OWNED);
2852 ksiginfo_init(&ksi);
2853 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2854 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2856 ksi.ksi_signo = sig;
2857 if (ksi.ksi_code == SI_TIMER)
2858 itimer_accept(p, ksi.ksi_timerid, &ksi);
2859 action = ps->ps_sigact[_SIG_IDX(sig)];
2861 if (KTRPOINT(td, KTR_PSIG))
2862 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2863 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2865 if (p->p_stops & S_SIG) {
2866 mtx_unlock(&ps->ps_mtx);
2867 stopevent(p, S_SIG, sig);
2868 mtx_lock(&ps->ps_mtx);
2871 if (action == SIG_DFL) {
2873 * Default action, where the default is to kill
2874 * the process. (Other cases were ignored above.)
2876 mtx_unlock(&ps->ps_mtx);
2881 * If we get here, the signal must be caught.
2883 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2884 ("postsig action"));
2886 * Set the new mask value and also defer further
2887 * occurrences of this signal.
2889 * Special case: user has done a sigsuspend. Here the
2890 * current mask is not of interest, but rather the
2891 * mask from before the sigsuspend is what we want
2892 * restored after the signal processing is completed.
2894 if (td->td_pflags & TDP_OLDMASK) {
2895 returnmask = td->td_oldsigmask;
2896 td->td_pflags &= ~TDP_OLDMASK;
2898 returnmask = td->td_sigmask;
2900 if (p->p_sig == sig) {
2904 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2905 postsig_done(sig, td, ps);
2911 * Kill the current process for stated reason.
2919 PROC_LOCK_ASSERT(p, MA_OWNED);
2920 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2922 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2923 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2924 p->p_flag |= P_WKILLED;
2925 kern_psignal(p, SIGKILL);
2929 * Force the current process to exit with the specified signal, dumping core
2930 * if appropriate. We bypass the normal tests for masked and caught signals,
2931 * allowing unrecoverable failures to terminate the process without changing
2932 * signal state. Mark the accounting record with the signal termination.
2933 * If dumping core, save the signal number for the debugger. Calls exit and
2941 struct proc *p = td->td_proc;
2943 PROC_LOCK_ASSERT(p, MA_OWNED);
2944 p->p_acflag |= AXSIG;
2946 * We must be single-threading to generate a core dump. This
2947 * ensures that the registers in the core file are up-to-date.
2948 * Also, the ELF dump handler assumes that the thread list doesn't
2949 * change out from under it.
2951 * XXX If another thread attempts to single-thread before us
2952 * (e.g. via fork()), we won't get a dump at all.
2954 if ((sigprop(sig) & SA_CORE) && thread_single(p, SINGLE_NO_EXIT) == 0) {
2957 * Log signals which would cause core dumps
2958 * (Log as LOG_INFO to appease those who don't want
2960 * XXX : Todo, as well as euid, write out ruid too
2961 * Note that coredump() drops proc lock.
2963 if (coredump(td) == 0)
2965 if (kern_logsigexit)
2967 "pid %d (%s), uid %d: exited on signal %d%s\n",
2968 p->p_pid, p->p_comm,
2969 td->td_ucred ? td->td_ucred->cr_uid : -1,
2971 sig & WCOREFLAG ? " (core dumped)" : "");
2974 exit1(td, W_EXITCODE(0, sig));
2979 * Send queued SIGCHLD to parent when child process's state
2983 sigparent(struct proc *p, int reason, int status)
2985 PROC_LOCK_ASSERT(p, MA_OWNED);
2986 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2988 if (p->p_ksi != NULL) {
2989 p->p_ksi->ksi_signo = SIGCHLD;
2990 p->p_ksi->ksi_code = reason;
2991 p->p_ksi->ksi_status = status;
2992 p->p_ksi->ksi_pid = p->p_pid;
2993 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2994 if (KSI_ONQ(p->p_ksi))
2997 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3001 childproc_jobstate(struct proc *p, int reason, int sig)
3005 PROC_LOCK_ASSERT(p, MA_OWNED);
3006 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3009 * Wake up parent sleeping in kern_wait(), also send
3010 * SIGCHLD to parent, but SIGCHLD does not guarantee
3011 * that parent will awake, because parent may masked
3014 p->p_pptr->p_flag |= P_STATCHILD;
3017 ps = p->p_pptr->p_sigacts;
3018 mtx_lock(&ps->ps_mtx);
3019 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3020 mtx_unlock(&ps->ps_mtx);
3021 sigparent(p, reason, sig);
3023 mtx_unlock(&ps->ps_mtx);
3027 childproc_stopped(struct proc *p, int reason)
3029 /* p_xstat is a plain signal number, not a full wait() status here. */
3030 childproc_jobstate(p, reason, p->p_xstat);
3034 childproc_continued(struct proc *p)
3036 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3040 childproc_exited(struct proc *p)
3043 int xstat = p->p_xstat; /* convert to int */
3046 if (WCOREDUMP(xstat))
3047 reason = CLD_DUMPED, status = WTERMSIG(xstat);
3048 else if (WIFSIGNALED(xstat))
3049 reason = CLD_KILLED, status = WTERMSIG(xstat);
3051 reason = CLD_EXITED, status = WEXITSTATUS(xstat);
3053 * XXX avoid calling wakeup(p->p_pptr), the work is
3056 sigparent(p, reason, status);
3060 * We only have 1 character for the core count in the format
3061 * string, so the range will be 0-9
3063 #define MAX_NUM_CORES 10
3064 static int num_cores = 5;
3067 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3072 new_val = num_cores;
3073 error = sysctl_handle_int(oidp, &new_val, 0, req);
3074 if (error != 0 || req->newptr == NULL)
3076 if (new_val > MAX_NUM_CORES)
3077 new_val = MAX_NUM_CORES;
3080 num_cores = new_val;
3083 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3084 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3086 #if defined(COMPRESS_USER_CORES)
3087 int compress_user_cores = 1;
3088 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
3089 &compress_user_cores, 0, "Compression of user corefiles");
3091 int compress_user_cores_gzlevel = -1; /* default level */
3092 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
3093 &compress_user_cores_gzlevel, -1, "Corefile gzip compression level");
3095 #define GZ_SUFFIX ".gz"
3096 #define GZ_SUFFIX_LEN 3
3099 static char corefilename[MAXPATHLEN] = {"%N.core"};
3100 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3101 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3102 sizeof(corefilename), "Process corefile name format string");
3105 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3106 * Expand the name described in corefilename, using name, uid, and pid
3107 * and open/create core file.
3108 * corefilename is a printf-like string, with three format specifiers:
3109 * %N name of process ("name")
3110 * %P process id (pid)
3112 * For example, "%N.core" is the default; they can be disabled completely
3113 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3114 * This is controlled by the sysctl variable kern.corefile (see above).
3117 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3118 int compress, struct vnode **vpp, char **namep)
3120 struct nameidata nd;
3123 char *hostname, *name;
3124 int indexpos, i, error, cmode, flags, oflags;
3127 format = corefilename;
3128 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3130 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3131 for (i = 0; format[i] != '\0'; i++) {
3132 switch (format[i]) {
3133 case '%': /* Format character */
3135 switch (format[i]) {
3137 sbuf_putc(&sb, '%');
3139 case 'H': /* hostname */
3140 if (hostname == NULL) {
3141 hostname = malloc(MAXHOSTNAMELEN,
3144 getcredhostname(td->td_ucred, hostname,
3146 sbuf_printf(&sb, "%s", hostname);
3148 case 'I': /* autoincrementing index */
3149 sbuf_printf(&sb, "0");
3150 indexpos = sbuf_len(&sb) - 1;
3152 case 'N': /* process name */
3153 sbuf_printf(&sb, "%s", comm);
3155 case 'P': /* process id */
3156 sbuf_printf(&sb, "%u", pid);
3158 case 'U': /* user id */
3159 sbuf_printf(&sb, "%u", uid);
3163 "Unknown format character %c in "
3164 "corename `%s'\n", format[i], format);
3169 sbuf_putc(&sb, format[i]);
3173 free(hostname, M_TEMP);
3174 #ifdef COMPRESS_USER_CORES
3176 sbuf_printf(&sb, GZ_SUFFIX);
3178 if (sbuf_error(&sb) != 0) {
3179 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3180 "long\n", (long)pid, comm, (u_long)uid);
3188 cmode = S_IRUSR | S_IWUSR;
3189 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3190 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3193 * If the core format has a %I in it, then we need to check
3194 * for existing corefiles before returning a name.
3195 * To do this we iterate over 0..num_cores to find a
3196 * non-existing core file name to use.
3198 if (indexpos != -1) {
3199 for (i = 0; i < num_cores; i++) {
3200 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3201 name[indexpos] = '0' + i;
3202 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3203 error = vn_open_cred(&nd, &flags, cmode, oflags,
3204 td->td_ucred, NULL);
3206 if (error == EEXIST)
3209 "pid %d (%s), uid (%u): Path `%s' failed "
3210 "on initial open test, error = %d\n",
3211 pid, comm, uid, name, error);
3217 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3218 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3219 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3223 audit_proc_coredump(td, name, error);
3228 NDFREE(&nd, NDF_ONLY_PNBUF);
3235 * Dump a process' core. The main routine does some
3236 * policy checking, and creates the name of the coredump;
3237 * then it passes on a vnode and a size limit to the process-specific
3238 * coredump routine if there is one; if there _is not_ one, it returns
3239 * ENOSYS; otherwise it returns the error from the process-specific routine.
3243 coredump(struct thread *td)
3245 struct proc *p = td->td_proc;
3246 struct ucred *cred = td->td_ucred;
3250 int error, error1, locked;
3252 char *name; /* name of corefile */
3256 #ifdef COMPRESS_USER_CORES
3257 compress = compress_user_cores;
3261 PROC_LOCK_ASSERT(p, MA_OWNED);
3262 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3263 _STOPEVENT(p, S_CORE, 0);
3265 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3266 (p->p_flag2 & P2_NOTRACE) != 0) {
3272 * Note that the bulk of limit checking is done after
3273 * the corefile is created. The exception is if the limit
3274 * for corefiles is 0, in which case we don't bother
3275 * creating the corefile at all. This layout means that
3276 * a corefile is truncated instead of not being created,
3277 * if it is larger than the limit.
3279 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3280 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3287 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress,
3292 /* Don't dump to non-regular files or files with links. */
3293 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3294 vattr.va_nlink != 1) {
3301 lf.l_whence = SEEK_SET;
3304 lf.l_type = F_WRLCK;
3305 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3307 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3308 lf.l_type = F_UNLCK;
3310 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3311 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3313 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3321 if (set_core_nodump_flag)
3322 vattr.va_flags = UF_NODUMP;
3323 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3324 VOP_SETATTR(vp, &vattr, cred);
3326 vn_finished_write(mp);
3328 p->p_acflag |= ACORE;
3331 if (p->p_sysent->sv_coredump != NULL) {
3332 error = p->p_sysent->sv_coredump(td, vp, limit,
3333 compress ? IMGACT_CORE_COMPRESS : 0);
3339 lf.l_type = F_UNLCK;
3340 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3343 error1 = vn_close(vp, FWRITE, cred, td);
3348 audit_proc_coredump(td, name, error);
3355 * Nonexistent system call-- signal process (may want to handle it). Flag
3356 * error in case process won't see signal immediately (blocked or ignored).
3358 #ifndef _SYS_SYSPROTO_H_
3367 struct nosys_args *args;
3369 struct proc *p = td->td_proc;
3372 tdsignal(td, SIGSYS);
3378 * Send a SIGIO or SIGURG signal to a process or process group using stored
3379 * credentials rather than those of the current process.
3382 pgsigio(sigiop, sig, checkctty)
3383 struct sigio **sigiop;
3387 struct sigio *sigio;
3389 ksiginfo_init(&ksi);
3390 ksi.ksi_signo = sig;
3391 ksi.ksi_code = SI_KERNEL;
3395 if (sigio == NULL) {
3399 if (sigio->sio_pgid > 0) {
3400 PROC_LOCK(sigio->sio_proc);
3401 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3402 kern_psignal(sigio->sio_proc, sig);
3403 PROC_UNLOCK(sigio->sio_proc);
3404 } else if (sigio->sio_pgid < 0) {
3407 PGRP_LOCK(sigio->sio_pgrp);
3408 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3410 if (p->p_state == PRS_NORMAL &&
3411 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3412 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3413 kern_psignal(p, sig);
3416 PGRP_UNLOCK(sigio->sio_pgrp);
3422 filt_sigattach(struct knote *kn)
3424 struct proc *p = curproc;
3426 kn->kn_ptr.p_proc = p;
3427 kn->kn_flags |= EV_CLEAR; /* automatically set */
3429 knlist_add(&p->p_klist, kn, 0);
3435 filt_sigdetach(struct knote *kn)
3437 struct proc *p = kn->kn_ptr.p_proc;
3439 knlist_remove(&p->p_klist, kn, 0);
3443 * signal knotes are shared with proc knotes, so we apply a mask to
3444 * the hint in order to differentiate them from process hints. This
3445 * could be avoided by using a signal-specific knote list, but probably
3446 * isn't worth the trouble.
3449 filt_signal(struct knote *kn, long hint)
3452 if (hint & NOTE_SIGNAL) {
3453 hint &= ~NOTE_SIGNAL;
3455 if (kn->kn_id == hint)
3458 return (kn->kn_data != 0);
3466 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3468 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3473 sigacts_free(struct sigacts *ps)
3476 if (refcount_release(&ps->ps_refcnt) == 0)
3478 mtx_destroy(&ps->ps_mtx);
3479 free(ps, M_SUBPROC);
3483 sigacts_hold(struct sigacts *ps)
3486 refcount_acquire(&ps->ps_refcnt);
3491 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3494 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3495 mtx_lock(&src->ps_mtx);
3496 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3497 mtx_unlock(&src->ps_mtx);
3501 sigacts_shared(struct sigacts *ps)
3504 return (ps->ps_refcnt > 1);