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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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, , , 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 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);
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);
976 * Reset stack state to the user stack.
977 * Clear set of signals caught on the signal stack.
980 MPASS(td->td_proc == p);
981 td->td_sigstk.ss_flags = SS_DISABLE;
982 td->td_sigstk.ss_size = 0;
983 td->td_sigstk.ss_sp = 0;
984 td->td_pflags &= ~TDP_ALTSTACK;
986 * Reset no zombies if child dies flag as Solaris does.
988 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
989 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
990 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
991 mtx_unlock(&ps->ps_mtx);
997 * Manipulate signal mask.
1000 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1003 sigset_t new_block, oset1;
1008 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1009 PROC_LOCK_ASSERT(p, MA_OWNED);
1012 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1013 ? MA_OWNED : MA_NOTOWNED);
1015 *oset = td->td_sigmask;
1022 oset1 = td->td_sigmask;
1023 SIGSETOR(td->td_sigmask, *set);
1024 new_block = td->td_sigmask;
1025 SIGSETNAND(new_block, oset1);
1028 SIGSETNAND(td->td_sigmask, *set);
1033 oset1 = td->td_sigmask;
1034 if (flags & SIGPROCMASK_OLD)
1035 SIGSETLO(td->td_sigmask, *set);
1037 td->td_sigmask = *set;
1038 new_block = td->td_sigmask;
1039 SIGSETNAND(new_block, oset1);
1048 * The new_block set contains signals that were not previously
1049 * blocked, but are blocked now.
1051 * In case we block any signal that was not previously blocked
1052 * for td, and process has the signal pending, try to schedule
1053 * signal delivery to some thread that does not block the
1054 * signal, possibly waking it up.
1056 if (p->p_numthreads != 1)
1057 reschedule_signals(p, new_block, flags);
1061 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1066 #ifndef _SYS_SYSPROTO_H_
1067 struct sigprocmask_args {
1069 const sigset_t *set;
1074 sys_sigprocmask(td, uap)
1075 register struct thread *td;
1076 struct sigprocmask_args *uap;
1079 sigset_t *setp, *osetp;
1082 setp = (uap->set != NULL) ? &set : NULL;
1083 osetp = (uap->oset != NULL) ? &oset : NULL;
1085 error = copyin(uap->set, setp, sizeof(set));
1089 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1090 if (osetp && !error) {
1091 error = copyout(osetp, uap->oset, sizeof(oset));
1096 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1097 #ifndef _SYS_SYSPROTO_H_
1098 struct osigprocmask_args {
1104 osigprocmask(td, uap)
1105 register struct thread *td;
1106 struct osigprocmask_args *uap;
1111 OSIG2SIG(uap->mask, set);
1112 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1113 SIG2OSIG(oset, td->td_retval[0]);
1116 #endif /* COMPAT_43 */
1119 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1125 error = copyin(uap->set, &set, sizeof(set));
1127 td->td_retval[0] = error;
1131 error = kern_sigtimedwait(td, set, &ksi, NULL);
1133 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1135 if (error == ERESTART)
1137 td->td_retval[0] = error;
1141 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1142 td->td_retval[0] = error;
1147 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1150 struct timespec *timeout;
1156 error = copyin(uap->timeout, &ts, sizeof(ts));
1164 error = copyin(uap->set, &set, sizeof(set));
1168 error = kern_sigtimedwait(td, set, &ksi, timeout);
1173 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1176 td->td_retval[0] = ksi.ksi_signo;
1181 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1187 error = copyin(uap->set, &set, sizeof(set));
1191 error = kern_sigtimedwait(td, set, &ksi, NULL);
1196 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1199 td->td_retval[0] = ksi.ksi_signo;
1204 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1205 struct timespec *timeout)
1208 sigset_t saved_mask, new_block;
1210 int error, sig, timo, timevalid = 0;
1211 struct timespec rts, ets, ts;
1219 if (timeout != NULL) {
1220 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1222 getnanouptime(&rts);
1224 timespecadd(&ets, timeout);
1228 /* Some signals can not be waited for. */
1229 SIG_CANTMASK(waitset);
1232 saved_mask = td->td_sigmask;
1233 SIGSETNAND(td->td_sigmask, waitset);
1235 mtx_lock(&ps->ps_mtx);
1237 mtx_unlock(&ps->ps_mtx);
1238 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1239 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1240 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1250 * POSIX says this must be checked after looking for pending
1253 if (timeout != NULL) {
1258 getnanouptime(&rts);
1259 if (timespeccmp(&rts, &ets, >=)) {
1264 timespecsub(&ts, &rts);
1265 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1271 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1273 if (timeout != NULL) {
1274 if (error == ERESTART) {
1275 /* Timeout can not be restarted. */
1277 } else if (error == EAGAIN) {
1278 /* We will calculate timeout by ourself. */
1284 new_block = saved_mask;
1285 SIGSETNAND(new_block, td->td_sigmask);
1286 td->td_sigmask = saved_mask;
1288 * Fewer signals can be delivered to us, reschedule signal
1291 if (p->p_numthreads != 1)
1292 reschedule_signals(p, new_block, 0);
1295 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1297 if (ksi->ksi_code == SI_TIMER)
1298 itimer_accept(p, ksi->ksi_timerid, ksi);
1301 if (KTRPOINT(td, KTR_PSIG)) {
1304 mtx_lock(&ps->ps_mtx);
1305 action = ps->ps_sigact[_SIG_IDX(sig)];
1306 mtx_unlock(&ps->ps_mtx);
1307 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1317 #ifndef _SYS_SYSPROTO_H_
1318 struct sigpending_args {
1323 sys_sigpending(td, uap)
1325 struct sigpending_args *uap;
1327 struct proc *p = td->td_proc;
1331 pending = p->p_sigqueue.sq_signals;
1332 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1334 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1337 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1338 #ifndef _SYS_SYSPROTO_H_
1339 struct osigpending_args {
1344 osigpending(td, uap)
1346 struct osigpending_args *uap;
1348 struct proc *p = td->td_proc;
1352 pending = p->p_sigqueue.sq_signals;
1353 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1355 SIG2OSIG(pending, td->td_retval[0]);
1358 #endif /* COMPAT_43 */
1360 #if defined(COMPAT_43)
1362 * Generalized interface signal handler, 4.3-compatible.
1364 #ifndef _SYS_SYSPROTO_H_
1365 struct osigvec_args {
1375 register struct osigvec_args *uap;
1378 struct sigaction nsa, osa;
1379 register struct sigaction *nsap, *osap;
1382 if (uap->signum <= 0 || uap->signum >= ONSIG)
1384 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1385 osap = (uap->osv != NULL) ? &osa : NULL;
1387 error = copyin(uap->nsv, &vec, sizeof(vec));
1390 nsap->sa_handler = vec.sv_handler;
1391 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1392 nsap->sa_flags = vec.sv_flags;
1393 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1395 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1396 if (osap && !error) {
1397 vec.sv_handler = osap->sa_handler;
1398 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1399 vec.sv_flags = osap->sa_flags;
1400 vec.sv_flags &= ~SA_NOCLDWAIT;
1401 vec.sv_flags ^= SA_RESTART;
1402 error = copyout(&vec, uap->osv, sizeof(vec));
1407 #ifndef _SYS_SYSPROTO_H_
1408 struct osigblock_args {
1414 register struct thread *td;
1415 struct osigblock_args *uap;
1419 OSIG2SIG(uap->mask, set);
1420 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1421 SIG2OSIG(oset, td->td_retval[0]);
1425 #ifndef _SYS_SYSPROTO_H_
1426 struct osigsetmask_args {
1431 osigsetmask(td, uap)
1433 struct osigsetmask_args *uap;
1437 OSIG2SIG(uap->mask, set);
1438 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1439 SIG2OSIG(oset, td->td_retval[0]);
1442 #endif /* COMPAT_43 */
1445 * Suspend calling thread until signal, providing mask to be set in the
1448 #ifndef _SYS_SYSPROTO_H_
1449 struct sigsuspend_args {
1450 const sigset_t *sigmask;
1455 sys_sigsuspend(td, uap)
1457 struct sigsuspend_args *uap;
1462 error = copyin(uap->sigmask, &mask, sizeof(mask));
1465 return (kern_sigsuspend(td, mask));
1469 kern_sigsuspend(struct thread *td, sigset_t mask)
1471 struct proc *p = td->td_proc;
1475 * When returning from sigsuspend, we want
1476 * the old mask to be restored after the
1477 * signal handler has finished. Thus, we
1478 * save it here and mark the sigacts structure
1482 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1483 SIGPROCMASK_PROC_LOCKED);
1484 td->td_pflags |= TDP_OLDMASK;
1487 * Process signals now. Otherwise, we can get spurious wakeup
1488 * due to signal entered process queue, but delivered to other
1489 * thread. But sigsuspend should return only on signal
1492 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1493 for (has_sig = 0; !has_sig;) {
1494 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1497 thread_suspend_check(0);
1498 mtx_lock(&p->p_sigacts->ps_mtx);
1499 while ((sig = cursig(td)) != 0)
1500 has_sig += postsig(sig);
1501 mtx_unlock(&p->p_sigacts->ps_mtx);
1504 td->td_errno = EINTR;
1505 td->td_pflags |= TDP_NERRNO;
1506 return (EJUSTRETURN);
1509 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1511 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1512 * convention: libc stub passes mask, not pointer, to save a copyin.
1514 #ifndef _SYS_SYSPROTO_H_
1515 struct osigsuspend_args {
1521 osigsuspend(td, uap)
1523 struct osigsuspend_args *uap;
1527 OSIG2SIG(uap->mask, mask);
1528 return (kern_sigsuspend(td, mask));
1530 #endif /* COMPAT_43 */
1532 #if defined(COMPAT_43)
1533 #ifndef _SYS_SYSPROTO_H_
1534 struct osigstack_args {
1535 struct sigstack *nss;
1536 struct sigstack *oss;
1543 register struct osigstack_args *uap;
1545 struct sigstack nss, oss;
1548 if (uap->nss != NULL) {
1549 error = copyin(uap->nss, &nss, sizeof(nss));
1553 oss.ss_sp = td->td_sigstk.ss_sp;
1554 oss.ss_onstack = sigonstack(cpu_getstack(td));
1555 if (uap->nss != NULL) {
1556 td->td_sigstk.ss_sp = nss.ss_sp;
1557 td->td_sigstk.ss_size = 0;
1558 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1559 td->td_pflags |= TDP_ALTSTACK;
1561 if (uap->oss != NULL)
1562 error = copyout(&oss, uap->oss, sizeof(oss));
1566 #endif /* COMPAT_43 */
1568 #ifndef _SYS_SYSPROTO_H_
1569 struct sigaltstack_args {
1576 sys_sigaltstack(td, uap)
1578 register struct sigaltstack_args *uap;
1583 if (uap->ss != NULL) {
1584 error = copyin(uap->ss, &ss, sizeof(ss));
1588 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1589 (uap->oss != NULL) ? &oss : NULL);
1592 if (uap->oss != NULL)
1593 error = copyout(&oss, uap->oss, sizeof(stack_t));
1598 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1600 struct proc *p = td->td_proc;
1603 oonstack = sigonstack(cpu_getstack(td));
1606 *oss = td->td_sigstk;
1607 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1608 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1614 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1616 if (!(ss->ss_flags & SS_DISABLE)) {
1617 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1620 td->td_sigstk = *ss;
1621 td->td_pflags |= TDP_ALTSTACK;
1623 td->td_pflags &= ~TDP_ALTSTACK;
1630 * Common code for kill process group/broadcast kill.
1631 * cp is calling process.
1634 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1646 sx_slock(&allproc_lock);
1647 FOREACH_PROC_IN_SYSTEM(p) {
1649 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1650 p == td->td_proc || p->p_state == PRS_NEW) {
1654 err = p_cansignal(td, p, sig);
1657 pksignal(p, sig, ksi);
1660 else if (ret == ESRCH)
1664 sx_sunlock(&allproc_lock);
1666 sx_slock(&proctree_lock);
1669 * zero pgid means send to my process group.
1671 pgrp = td->td_proc->p_pgrp;
1674 pgrp = pgfind(pgid);
1676 sx_sunlock(&proctree_lock);
1680 sx_sunlock(&proctree_lock);
1681 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1683 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1684 p->p_state == PRS_NEW) {
1688 err = p_cansignal(td, p, sig);
1691 pksignal(p, sig, ksi);
1694 else if (ret == ESRCH)
1703 #ifndef _SYS_SYSPROTO_H_
1711 sys_kill(struct thread *td, struct kill_args *uap)
1718 * A process in capability mode can send signals only to himself.
1719 * The main rationale behind this is that abort(3) is implemented as
1720 * kill(getpid(), SIGABRT).
1722 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1725 AUDIT_ARG_SIGNUM(uap->signum);
1726 AUDIT_ARG_PID(uap->pid);
1727 if ((u_int)uap->signum > _SIG_MAXSIG)
1730 ksiginfo_init(&ksi);
1731 ksi.ksi_signo = uap->signum;
1732 ksi.ksi_code = SI_USER;
1733 ksi.ksi_pid = td->td_proc->p_pid;
1734 ksi.ksi_uid = td->td_ucred->cr_ruid;
1737 /* kill single process */
1738 if ((p = pfind(uap->pid)) == NULL) {
1739 if ((p = zpfind(uap->pid)) == NULL)
1742 AUDIT_ARG_PROCESS(p);
1743 error = p_cansignal(td, p, uap->signum);
1744 if (error == 0 && uap->signum)
1745 pksignal(p, uap->signum, &ksi);
1750 case -1: /* broadcast signal */
1751 return (killpg1(td, uap->signum, 0, 1, &ksi));
1752 case 0: /* signal own process group */
1753 return (killpg1(td, uap->signum, 0, 0, &ksi));
1754 default: /* negative explicit process group */
1755 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1763 struct pdkill_args *uap;
1767 cap_rights_t rights;
1770 AUDIT_ARG_SIGNUM(uap->signum);
1771 AUDIT_ARG_FD(uap->fd);
1772 if ((u_int)uap->signum > _SIG_MAXSIG)
1775 error = procdesc_find(td, uap->fd,
1776 cap_rights_init(&rights, CAP_PDKILL), &p);
1779 AUDIT_ARG_PROCESS(p);
1780 error = p_cansignal(td, p, uap->signum);
1781 if (error == 0 && uap->signum)
1782 kern_psignal(p, uap->signum);
1790 #if defined(COMPAT_43)
1791 #ifndef _SYS_SYSPROTO_H_
1792 struct okillpg_args {
1799 okillpg(struct thread *td, struct okillpg_args *uap)
1803 AUDIT_ARG_SIGNUM(uap->signum);
1804 AUDIT_ARG_PID(uap->pgid);
1805 if ((u_int)uap->signum > _SIG_MAXSIG)
1808 ksiginfo_init(&ksi);
1809 ksi.ksi_signo = uap->signum;
1810 ksi.ksi_code = SI_USER;
1811 ksi.ksi_pid = td->td_proc->p_pid;
1812 ksi.ksi_uid = td->td_ucred->cr_ruid;
1813 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1815 #endif /* COMPAT_43 */
1817 #ifndef _SYS_SYSPROTO_H_
1818 struct sigqueue_args {
1821 /* union sigval */ void *value;
1825 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1831 if ((u_int)uap->signum > _SIG_MAXSIG)
1835 * Specification says sigqueue can only send signal to
1841 if ((p = pfind(uap->pid)) == NULL) {
1842 if ((p = zpfind(uap->pid)) == NULL)
1845 error = p_cansignal(td, p, uap->signum);
1846 if (error == 0 && uap->signum != 0) {
1847 ksiginfo_init(&ksi);
1848 ksi.ksi_flags = KSI_SIGQ;
1849 ksi.ksi_signo = uap->signum;
1850 ksi.ksi_code = SI_QUEUE;
1851 ksi.ksi_pid = td->td_proc->p_pid;
1852 ksi.ksi_uid = td->td_ucred->cr_ruid;
1853 ksi.ksi_value.sival_ptr = uap->value;
1854 error = pksignal(p, ksi.ksi_signo, &ksi);
1861 * Send a signal to a process group.
1864 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1869 sx_slock(&proctree_lock);
1870 pgrp = pgfind(pgid);
1871 sx_sunlock(&proctree_lock);
1873 pgsignal(pgrp, sig, 0, ksi);
1880 * Send a signal to a process group. If checktty is 1,
1881 * limit to members which have a controlling terminal.
1884 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1889 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1890 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1892 if (p->p_state == PRS_NORMAL &&
1893 (checkctty == 0 || p->p_flag & P_CONTROLT))
1894 pksignal(p, sig, ksi);
1902 * Recalculate the signal mask and reset the signal disposition after
1903 * usermode frame for delivery is formed. Should be called after
1904 * mach-specific routine, because sysent->sv_sendsig() needs correct
1905 * ps_siginfo and signal mask.
1908 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1912 mtx_assert(&ps->ps_mtx, MA_OWNED);
1913 td->td_ru.ru_nsignals++;
1914 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1915 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1916 SIGADDSET(mask, sig);
1917 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1918 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1919 if (SIGISMEMBER(ps->ps_sigreset, sig))
1925 * Send a signal caused by a trap to the current thread. If it will be
1926 * caught immediately, deliver it with correct code. Otherwise, post it
1930 trapsignal(struct thread *td, ksiginfo_t *ksi)
1938 sig = ksi->ksi_signo;
1939 code = ksi->ksi_code;
1940 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1944 mtx_lock(&ps->ps_mtx);
1945 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1946 !SIGISMEMBER(td->td_sigmask, sig)) {
1948 if (KTRPOINT(curthread, KTR_PSIG))
1949 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1950 &td->td_sigmask, code);
1952 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1953 ksi, &td->td_sigmask);
1954 postsig_done(sig, td, ps);
1955 mtx_unlock(&ps->ps_mtx);
1958 * Avoid a possible infinite loop if the thread
1959 * masking the signal or process is ignoring the
1962 if (kern_forcesigexit &&
1963 (SIGISMEMBER(td->td_sigmask, sig) ||
1964 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1965 SIGDELSET(td->td_sigmask, sig);
1966 SIGDELSET(ps->ps_sigcatch, sig);
1967 SIGDELSET(ps->ps_sigignore, sig);
1968 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1970 mtx_unlock(&ps->ps_mtx);
1971 p->p_code = code; /* XXX for core dump/debugger */
1972 p->p_sig = sig; /* XXX to verify code */
1973 tdsendsignal(p, td, sig, ksi);
1978 static struct thread *
1979 sigtd(struct proc *p, int sig, int prop)
1981 struct thread *td, *signal_td;
1983 PROC_LOCK_ASSERT(p, MA_OWNED);
1986 * Check if current thread can handle the signal without
1987 * switching context to another thread.
1989 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1992 FOREACH_THREAD_IN_PROC(p, td) {
1993 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1998 if (signal_td == NULL)
1999 signal_td = FIRST_THREAD_IN_PROC(p);
2004 * Send the signal to the process. If the signal has an action, the action
2005 * is usually performed by the target process rather than the caller; we add
2006 * the signal to the set of pending signals for the process.
2009 * o When a stop signal is sent to a sleeping process that takes the
2010 * default action, the process is stopped without awakening it.
2011 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2012 * regardless of the signal action (eg, blocked or ignored).
2014 * Other ignored signals are discarded immediately.
2016 * NB: This function may be entered from the debugger via the "kill" DDB
2017 * command. There is little that can be done to mitigate the possibly messy
2018 * side effects of this unwise possibility.
2021 kern_psignal(struct proc *p, int sig)
2025 ksiginfo_init(&ksi);
2026 ksi.ksi_signo = sig;
2027 ksi.ksi_code = SI_KERNEL;
2028 (void) tdsendsignal(p, NULL, sig, &ksi);
2032 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2035 return (tdsendsignal(p, NULL, sig, ksi));
2038 /* Utility function for finding a thread to send signal event to. */
2040 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2044 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2045 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2057 tdsignal(struct thread *td, int sig)
2061 ksiginfo_init(&ksi);
2062 ksi.ksi_signo = sig;
2063 ksi.ksi_code = SI_KERNEL;
2064 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2068 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2071 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2075 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2078 sigqueue_t *sigqueue;
2085 MPASS(td == NULL || p == td->td_proc);
2086 PROC_LOCK_ASSERT(p, MA_OWNED);
2088 if (!_SIG_VALID(sig))
2089 panic("%s(): invalid signal %d", __func__, sig);
2091 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2094 * IEEE Std 1003.1-2001: return success when killing a zombie.
2096 if (p->p_state == PRS_ZOMBIE) {
2097 if (ksi && (ksi->ksi_flags & KSI_INS))
2098 ksiginfo_tryfree(ksi);
2103 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2104 prop = sigprop(sig);
2107 td = sigtd(p, sig, prop);
2108 sigqueue = &p->p_sigqueue;
2110 sigqueue = &td->td_sigqueue;
2112 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2115 * If the signal is being ignored,
2116 * then we forget about it immediately.
2117 * (Note: we don't set SIGCONT in ps_sigignore,
2118 * and if it is set to SIG_IGN,
2119 * action will be SIG_DFL here.)
2121 mtx_lock(&ps->ps_mtx);
2122 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2123 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2125 mtx_unlock(&ps->ps_mtx);
2126 if (ksi && (ksi->ksi_flags & KSI_INS))
2127 ksiginfo_tryfree(ksi);
2130 if (SIGISMEMBER(td->td_sigmask, sig))
2132 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2136 if (SIGISMEMBER(ps->ps_sigintr, sig))
2140 mtx_unlock(&ps->ps_mtx);
2143 sigqueue_delete_stopmask_proc(p);
2144 else if (prop & SA_STOP) {
2146 * If sending a tty stop signal to a member of an orphaned
2147 * process group, discard the signal here if the action
2148 * is default; don't stop the process below if sleeping,
2149 * and don't clear any pending SIGCONT.
2151 if ((prop & SA_TTYSTOP) &&
2152 (p->p_pgrp->pg_jobc == 0) &&
2153 (action == SIG_DFL)) {
2154 if (ksi && (ksi->ksi_flags & KSI_INS))
2155 ksiginfo_tryfree(ksi);
2158 sigqueue_delete_proc(p, SIGCONT);
2159 if (p->p_flag & P_CONTINUED) {
2160 p->p_flag &= ~P_CONTINUED;
2161 PROC_LOCK(p->p_pptr);
2162 sigqueue_take(p->p_ksi);
2163 PROC_UNLOCK(p->p_pptr);
2167 ret = sigqueue_add(sigqueue, sig, ksi);
2172 * Defer further processing for signals which are held,
2173 * except that stopped processes must be continued by SIGCONT.
2175 if (action == SIG_HOLD &&
2176 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2179 * SIGKILL: Remove procfs STOPEVENTs and ptrace events.
2181 if (sig == SIGKILL) {
2183 /* from procfs_ioctl.c: PIOCBIC */
2185 /* from procfs_ioctl.c: PIOCCONT */
2190 * Some signals have a process-wide effect and a per-thread
2191 * component. Most processing occurs when the process next
2192 * tries to cross the user boundary, however there are some
2193 * times when processing needs to be done immediately, such as
2194 * waking up threads so that they can cross the user boundary.
2195 * We try to do the per-process part here.
2197 if (P_SHOULDSTOP(p)) {
2198 KASSERT(!(p->p_flag & P_WEXIT),
2199 ("signal to stopped but exiting process"));
2200 if (sig == SIGKILL) {
2202 * If traced process is already stopped,
2203 * then no further action is necessary.
2205 if (p->p_flag & P_TRACED)
2208 * SIGKILL sets process running.
2209 * It will die elsewhere.
2210 * All threads must be restarted.
2212 p->p_flag &= ~P_STOPPED_SIG;
2216 if (prop & SA_CONT) {
2218 * If traced process is already stopped,
2219 * then no further action is necessary.
2221 if (p->p_flag & P_TRACED)
2224 * If SIGCONT is default (or ignored), we continue the
2225 * process but don't leave the signal in sigqueue as
2226 * it has no further action. If SIGCONT is held, we
2227 * continue the process and leave the signal in
2228 * sigqueue. If the process catches SIGCONT, let it
2229 * handle the signal itself. If it isn't waiting on
2230 * an event, it goes back to run state.
2231 * Otherwise, process goes back to sleep state.
2233 p->p_flag &= ~P_STOPPED_SIG;
2235 if (p->p_numthreads == p->p_suspcount) {
2237 p->p_flag |= P_CONTINUED;
2238 p->p_xstat = SIGCONT;
2239 PROC_LOCK(p->p_pptr);
2240 childproc_continued(p);
2241 PROC_UNLOCK(p->p_pptr);
2244 if (action == SIG_DFL) {
2245 thread_unsuspend(p);
2247 sigqueue_delete(sigqueue, sig);
2250 if (action == SIG_CATCH) {
2252 * The process wants to catch it so it needs
2253 * to run at least one thread, but which one?
2259 * The signal is not ignored or caught.
2261 thread_unsuspend(p);
2266 if (prop & SA_STOP) {
2268 * If traced process is already stopped,
2269 * then no further action is necessary.
2271 if (p->p_flag & P_TRACED)
2274 * Already stopped, don't need to stop again
2275 * (If we did the shell could get confused).
2276 * Just make sure the signal STOP bit set.
2278 p->p_flag |= P_STOPPED_SIG;
2279 sigqueue_delete(sigqueue, sig);
2284 * All other kinds of signals:
2285 * If a thread is sleeping interruptibly, simulate a
2286 * wakeup so that when it is continued it will be made
2287 * runnable and can look at the signal. However, don't make
2288 * the PROCESS runnable, leave it stopped.
2289 * It may run a bit until it hits a thread_suspend_check().
2294 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2295 wakeup_swapper = sleepq_abort(td, intrval);
2302 * Mutexes are short lived. Threads waiting on them will
2303 * hit thread_suspend_check() soon.
2305 } else if (p->p_state == PRS_NORMAL) {
2306 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2307 tdsigwakeup(td, sig, action, intrval);
2311 MPASS(action == SIG_DFL);
2313 if (prop & SA_STOP) {
2314 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2316 p->p_flag |= P_STOPPED_SIG;
2319 sig_suspend_threads(td, p, 1);
2320 if (p->p_numthreads == p->p_suspcount) {
2322 * only thread sending signal to another
2323 * process can reach here, if thread is sending
2324 * signal to its process, because thread does
2325 * not suspend itself here, p_numthreads
2326 * should never be equal to p_suspcount.
2330 sigqueue_delete_proc(p, p->p_xstat);
2336 /* Not in "NORMAL" state. discard the signal. */
2337 sigqueue_delete(sigqueue, sig);
2342 * The process is not stopped so we need to apply the signal to all the
2346 tdsigwakeup(td, sig, action, intrval);
2348 thread_unsuspend(p);
2351 /* If we jump here, proc slock should not be owned. */
2352 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2357 * The force of a signal has been directed against a single
2358 * thread. We need to see what we can do about knocking it
2359 * out of any sleep it may be in etc.
2362 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2364 struct proc *p = td->td_proc;
2369 PROC_LOCK_ASSERT(p, MA_OWNED);
2370 prop = sigprop(sig);
2375 * Bring the priority of a thread up if we want it to get
2376 * killed in this lifetime. Be careful to avoid bumping the
2377 * priority of the idle thread, since we still allow to signal
2380 if (action == SIG_DFL && (prop & SA_KILL) != 0 &&
2381 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2382 sched_prio(td, PUSER);
2383 if (TD_ON_SLEEPQ(td)) {
2385 * If thread is sleeping uninterruptibly
2386 * we can't interrupt the sleep... the signal will
2387 * be noticed when the process returns through
2388 * trap() or syscall().
2390 if ((td->td_flags & TDF_SINTR) == 0)
2393 * If SIGCONT is default (or ignored) and process is
2394 * asleep, we are finished; the process should not
2397 if ((prop & SA_CONT) && action == SIG_DFL) {
2400 sigqueue_delete(&p->p_sigqueue, sig);
2402 * It may be on either list in this state.
2403 * Remove from both for now.
2405 sigqueue_delete(&td->td_sigqueue, sig);
2410 * Don't awaken a sleeping thread for SIGSTOP if the
2411 * STOP signal is deferred.
2413 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2417 * Give low priority threads a better chance to run.
2419 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2420 sched_prio(td, PUSER);
2422 wakeup_swapper = sleepq_abort(td, intrval);
2425 * Other states do nothing with the signal immediately,
2426 * other than kicking ourselves if we are running.
2427 * It will either never be noticed, or noticed very soon.
2430 if (TD_IS_RUNNING(td) && td != curthread)
2442 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2446 PROC_LOCK_ASSERT(p, MA_OWNED);
2447 PROC_SLOCK_ASSERT(p, MA_OWNED);
2449 FOREACH_THREAD_IN_PROC(p, td2) {
2451 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2452 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2453 (td2->td_flags & TDF_SINTR)) {
2454 if (td2->td_flags & TDF_SBDRY) {
2456 * Once a thread is asleep with
2457 * TDF_SBDRY set, it should never
2458 * become suspended due to this check.
2460 KASSERT(!TD_IS_SUSPENDED(td2),
2461 ("thread with deferred stops suspended"));
2462 } else if (!TD_IS_SUSPENDED(td2)) {
2463 thread_suspend_one(td2);
2465 } else if (!TD_IS_SUSPENDED(td2)) {
2466 if (sending || td != td2)
2467 td2->td_flags |= TDF_ASTPENDING;
2469 if (TD_IS_RUNNING(td2) && td2 != td)
2470 forward_signal(td2);
2478 ptracestop(struct thread *td, int sig)
2480 struct proc *p = td->td_proc;
2482 PROC_LOCK_ASSERT(p, MA_OWNED);
2483 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2484 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2485 &p->p_mtx.lock_object, "Stopping for traced signal");
2487 td->td_dbgflags |= TDB_XSIG;
2489 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2490 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2492 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2493 if (p->p_flag & P_SINGLE_EXIT &&
2494 !(td->td_dbgflags & TDB_EXIT)) {
2496 * Ignore ptrace stops except for thread exit
2497 * events when the process exits.
2499 td->td_dbgflags &= ~TDB_XSIG;
2505 * Make wait(2) work. Ensure that right after the
2506 * attach, the thread which was decided to become the
2507 * leader of attach gets reported to the waiter.
2508 * Otherwise, just avoid overwriting another thread's
2509 * assignment to p_xthread. If another thread has
2510 * already set p_xthread, the current thread will get
2511 * a chance to report itself upon the next iteration.
2513 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2514 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2515 p->p_xthread == NULL)) {
2518 td->td_dbgflags &= ~TDB_FSTP;
2519 p->p_flag2 &= ~P2_PTRACE_FSTP;
2520 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2521 sig_suspend_threads(td, p, 0);
2523 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2524 td->td_dbgflags &= ~TDB_STOPATFORK;
2525 cv_broadcast(&p->p_dbgwait);
2528 thread_suspend_switch(td, p);
2529 if (p->p_xthread == td)
2530 p->p_xthread = NULL;
2531 if (!(p->p_flag & P_TRACED))
2533 if (td->td_dbgflags & TDB_SUSPEND) {
2534 if (p->p_flag & P_SINGLE_EXIT)
2540 return (td->td_xsig);
2544 reschedule_signals(struct proc *p, sigset_t block, int flags)
2550 PROC_LOCK_ASSERT(p, MA_OWNED);
2552 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2553 MA_OWNED : MA_NOTOWNED);
2554 if (SIGISEMPTY(p->p_siglist))
2556 SIGSETAND(block, p->p_siglist);
2557 while ((sig = sig_ffs(&block)) != 0) {
2558 SIGDELSET(block, sig);
2559 td = sigtd(p, sig, 0);
2561 if (!(flags & SIGPROCMASK_PS_LOCKED))
2562 mtx_lock(&ps->ps_mtx);
2563 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2564 tdsigwakeup(td, sig, SIG_CATCH,
2565 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2567 if (!(flags & SIGPROCMASK_PS_LOCKED))
2568 mtx_unlock(&ps->ps_mtx);
2573 tdsigcleanup(struct thread *td)
2579 PROC_LOCK_ASSERT(p, MA_OWNED);
2581 sigqueue_flush(&td->td_sigqueue);
2582 if (p->p_numthreads == 1)
2586 * Since we cannot handle signals, notify signal post code
2587 * about this by filling the sigmask.
2589 * Also, if needed, wake up thread(s) that do not block the
2590 * same signals as the exiting thread, since the thread might
2591 * have been selected for delivery and woken up.
2593 SIGFILLSET(unblocked);
2594 SIGSETNAND(unblocked, td->td_sigmask);
2595 SIGFILLSET(td->td_sigmask);
2596 reschedule_signals(p, unblocked, 0);
2601 * Defer the delivery of SIGSTOP for the current thread. Returns true
2602 * if stops were deferred and false if they were already deferred.
2610 if (td->td_flags & TDF_SBDRY)
2613 td->td_flags |= TDF_SBDRY;
2619 * Permit the delivery of SIGSTOP for the current thread. This does
2620 * not immediately suspend if a stop was posted. Instead, the thread
2621 * will suspend either via ast() or a subsequent interruptible sleep.
2631 prev = (td->td_flags & TDF_SBDRY) != 0;
2632 td->td_flags &= ~TDF_SBDRY;
2638 * If the current process has received a signal (should be caught or cause
2639 * termination, should interrupt current syscall), return the signal number.
2640 * Stop signals with default action are processed immediately, then cleared;
2641 * they aren't returned. This is checked after each entry to the system for
2642 * a syscall or trap (though this can usually be done without calling issignal
2643 * by checking the pending signal masks in cursig.) The normal call
2646 * while (sig = cursig(curthread))
2650 issignal(struct thread *td)
2654 struct sigqueue *queue;
2655 sigset_t sigpending;
2656 int sig, prop, newsig;
2660 mtx_assert(&ps->ps_mtx, MA_OWNED);
2661 PROC_LOCK_ASSERT(p, MA_OWNED);
2663 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2665 sigpending = td->td_sigqueue.sq_signals;
2666 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2667 SIGSETNAND(sigpending, td->td_sigmask);
2669 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2670 SIG_STOPSIGMASK(sigpending);
2671 if (SIGISEMPTY(sigpending)) /* no signal to send */
2673 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2674 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2675 SIGISMEMBER(sigpending, SIGSTOP)) {
2677 * If debugger just attached, always consume
2678 * SIGSTOP from ptrace(PT_ATTACH) first, to
2679 * execute the debugger attach ritual in
2683 td->td_dbgflags |= TDB_FSTP;
2685 sig = sig_ffs(&sigpending);
2688 if (p->p_stops & S_SIG) {
2689 mtx_unlock(&ps->ps_mtx);
2690 stopevent(p, S_SIG, sig);
2691 mtx_lock(&ps->ps_mtx);
2695 * We should see pending but ignored signals
2696 * only if P_TRACED was on when they were posted.
2698 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2699 sigqueue_delete(&td->td_sigqueue, sig);
2700 sigqueue_delete(&p->p_sigqueue, sig);
2703 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2705 * If traced, always stop.
2706 * Remove old signal from queue before the stop.
2707 * XXX shrug off debugger, it causes siginfo to
2710 queue = &td->td_sigqueue;
2711 td->td_dbgksi.ksi_signo = 0;
2712 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2713 queue = &p->p_sigqueue;
2714 sigqueue_get(queue, sig, &td->td_dbgksi);
2717 mtx_unlock(&ps->ps_mtx);
2718 newsig = ptracestop(td, sig);
2719 mtx_lock(&ps->ps_mtx);
2721 if (sig != newsig) {
2724 * If parent wants us to take the signal,
2725 * then it will leave it in p->p_xstat;
2726 * otherwise we just look for signals again.
2733 * Put the new signal into td_sigqueue. If the
2734 * signal is being masked, look for other
2737 sigqueue_add(queue, sig, NULL);
2738 if (SIGISMEMBER(td->td_sigmask, sig))
2742 if (td->td_dbgksi.ksi_signo != 0) {
2743 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2744 if (sigqueue_add(&td->td_sigqueue, sig,
2745 &td->td_dbgksi) != 0)
2746 td->td_dbgksi.ksi_signo = 0;
2748 if (td->td_dbgksi.ksi_signo == 0)
2749 sigqueue_add(&td->td_sigqueue, sig,
2754 * If the traced bit got turned off, go back up
2755 * to the top to rescan signals. This ensures
2756 * that p_sig* and p_sigact are consistent.
2758 if ((p->p_flag & P_TRACED) == 0)
2762 prop = sigprop(sig);
2765 * Decide whether the signal should be returned.
2766 * Return the signal's number, or fall through
2767 * to clear it from the pending mask.
2769 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2771 case (intptr_t)SIG_DFL:
2773 * Don't take default actions on system processes.
2775 if (p->p_pid <= 1) {
2778 * Are you sure you want to ignore SIGSEGV
2781 printf("Process (pid %lu) got signal %d\n",
2782 (u_long)p->p_pid, sig);
2784 break; /* == ignore */
2787 * If there is a pending stop signal to process
2788 * with default action, stop here,
2789 * then clear the signal. However,
2790 * if process is member of an orphaned
2791 * process group, ignore tty stop signals.
2793 if (prop & SA_STOP) {
2794 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2795 (p->p_pgrp->pg_jobc == 0 &&
2797 break; /* == ignore */
2798 mtx_unlock(&ps->ps_mtx);
2799 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2800 &p->p_mtx.lock_object, "Catching SIGSTOP");
2801 sigqueue_delete(&td->td_sigqueue, sig);
2802 sigqueue_delete(&p->p_sigqueue, sig);
2803 p->p_flag |= P_STOPPED_SIG;
2806 sig_suspend_threads(td, p, 0);
2807 thread_suspend_switch(td, p);
2809 mtx_lock(&ps->ps_mtx);
2811 } else if (prop & SA_IGNORE) {
2813 * Except for SIGCONT, shouldn't get here.
2814 * Default action is to ignore; drop it.
2816 break; /* == ignore */
2821 case (intptr_t)SIG_IGN:
2823 * Masking above should prevent us ever trying
2824 * to take action on an ignored signal other
2825 * than SIGCONT, unless process is traced.
2827 if ((prop & SA_CONT) == 0 &&
2828 (p->p_flag & P_TRACED) == 0)
2829 printf("issignal\n");
2830 break; /* == ignore */
2834 * This signal has an action, let
2835 * postsig() process it.
2839 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2840 sigqueue_delete(&p->p_sigqueue, sig);
2847 thread_stopped(struct proc *p)
2851 PROC_LOCK_ASSERT(p, MA_OWNED);
2852 PROC_SLOCK_ASSERT(p, MA_OWNED);
2856 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2858 p->p_flag &= ~P_WAITED;
2859 PROC_LOCK(p->p_pptr);
2860 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2861 CLD_TRAPPED : CLD_STOPPED);
2862 PROC_UNLOCK(p->p_pptr);
2868 * Take the action for the specified signal
2869 * from the current set of pending signals.
2875 struct thread *td = curthread;
2876 register struct proc *p = td->td_proc;
2880 sigset_t returnmask;
2882 KASSERT(sig != 0, ("postsig"));
2884 PROC_LOCK_ASSERT(p, MA_OWNED);
2886 mtx_assert(&ps->ps_mtx, MA_OWNED);
2887 ksiginfo_init(&ksi);
2888 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2889 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2891 ksi.ksi_signo = sig;
2892 if (ksi.ksi_code == SI_TIMER)
2893 itimer_accept(p, ksi.ksi_timerid, &ksi);
2894 action = ps->ps_sigact[_SIG_IDX(sig)];
2896 if (KTRPOINT(td, KTR_PSIG))
2897 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2898 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2900 if (p->p_stops & S_SIG) {
2901 mtx_unlock(&ps->ps_mtx);
2902 stopevent(p, S_SIG, sig);
2903 mtx_lock(&ps->ps_mtx);
2906 if (action == SIG_DFL) {
2908 * Default action, where the default is to kill
2909 * the process. (Other cases were ignored above.)
2911 mtx_unlock(&ps->ps_mtx);
2916 * If we get here, the signal must be caught.
2918 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2919 ("postsig action"));
2921 * Set the new mask value and also defer further
2922 * occurrences of this signal.
2924 * Special case: user has done a sigsuspend. Here the
2925 * current mask is not of interest, but rather the
2926 * mask from before the sigsuspend is what we want
2927 * restored after the signal processing is completed.
2929 if (td->td_pflags & TDP_OLDMASK) {
2930 returnmask = td->td_oldsigmask;
2931 td->td_pflags &= ~TDP_OLDMASK;
2933 returnmask = td->td_sigmask;
2935 if (p->p_sig == sig) {
2939 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2940 postsig_done(sig, td, ps);
2946 * Kill the current process for stated reason.
2954 PROC_LOCK_ASSERT(p, MA_OWNED);
2955 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2957 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2958 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2959 p->p_flag |= P_WKILLED;
2960 kern_psignal(p, SIGKILL);
2964 * Force the current process to exit with the specified signal, dumping core
2965 * if appropriate. We bypass the normal tests for masked and caught signals,
2966 * allowing unrecoverable failures to terminate the process without changing
2967 * signal state. Mark the accounting record with the signal termination.
2968 * If dumping core, save the signal number for the debugger. Calls exit and
2976 struct proc *p = td->td_proc;
2978 PROC_LOCK_ASSERT(p, MA_OWNED);
2979 p->p_acflag |= AXSIG;
2981 * We must be single-threading to generate a core dump. This
2982 * ensures that the registers in the core file are up-to-date.
2983 * Also, the ELF dump handler assumes that the thread list doesn't
2984 * change out from under it.
2986 * XXX If another thread attempts to single-thread before us
2987 * (e.g. via fork()), we won't get a dump at all.
2989 if ((sigprop(sig) & SA_CORE) && thread_single(p, SINGLE_NO_EXIT) == 0) {
2992 * Log signals which would cause core dumps
2993 * (Log as LOG_INFO to appease those who don't want
2995 * XXX : Todo, as well as euid, write out ruid too
2996 * Note that coredump() drops proc lock.
2998 if (coredump(td) == 0)
3000 if (kern_logsigexit)
3002 "pid %d (%s), uid %d: exited on signal %d%s\n",
3003 p->p_pid, p->p_comm,
3004 td->td_ucred ? td->td_ucred->cr_uid : -1,
3006 sig & WCOREFLAG ? " (core dumped)" : "");
3009 exit1(td, W_EXITCODE(0, sig));
3014 * Send queued SIGCHLD to parent when child process's state
3018 sigparent(struct proc *p, int reason, int status)
3020 PROC_LOCK_ASSERT(p, MA_OWNED);
3021 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3023 if (p->p_ksi != NULL) {
3024 p->p_ksi->ksi_signo = SIGCHLD;
3025 p->p_ksi->ksi_code = reason;
3026 p->p_ksi->ksi_status = status;
3027 p->p_ksi->ksi_pid = p->p_pid;
3028 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3029 if (KSI_ONQ(p->p_ksi))
3032 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3036 childproc_jobstate(struct proc *p, int reason, int sig)
3040 PROC_LOCK_ASSERT(p, MA_OWNED);
3041 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3044 * Wake up parent sleeping in kern_wait(), also send
3045 * SIGCHLD to parent, but SIGCHLD does not guarantee
3046 * that parent will awake, because parent may masked
3049 p->p_pptr->p_flag |= P_STATCHILD;
3052 ps = p->p_pptr->p_sigacts;
3053 mtx_lock(&ps->ps_mtx);
3054 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3055 mtx_unlock(&ps->ps_mtx);
3056 sigparent(p, reason, sig);
3058 mtx_unlock(&ps->ps_mtx);
3062 childproc_stopped(struct proc *p, int reason)
3064 /* p_xstat is a plain signal number, not a full wait() status here. */
3065 childproc_jobstate(p, reason, p->p_xstat);
3069 childproc_continued(struct proc *p)
3071 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3075 childproc_exited(struct proc *p)
3078 int xstat = p->p_xstat; /* convert to int */
3081 if (WCOREDUMP(xstat))
3082 reason = CLD_DUMPED, status = WTERMSIG(xstat);
3083 else if (WIFSIGNALED(xstat))
3084 reason = CLD_KILLED, status = WTERMSIG(xstat);
3086 reason = CLD_EXITED, status = WEXITSTATUS(xstat);
3088 * XXX avoid calling wakeup(p->p_pptr), the work is
3091 sigparent(p, reason, status);
3095 * We only have 1 character for the core count in the format
3096 * string, so the range will be 0-9
3098 #define MAX_NUM_CORES 10
3099 static int num_cores = 5;
3102 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3107 new_val = num_cores;
3108 error = sysctl_handle_int(oidp, &new_val, 0, req);
3109 if (error != 0 || req->newptr == NULL)
3111 if (new_val > MAX_NUM_CORES)
3112 new_val = MAX_NUM_CORES;
3115 num_cores = new_val;
3118 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3119 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3121 #if defined(COMPRESS_USER_CORES)
3122 int compress_user_cores = 1;
3123 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
3124 &compress_user_cores, 0, "Compression of user corefiles");
3126 int compress_user_cores_gzlevel = -1; /* default level */
3127 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
3128 &compress_user_cores_gzlevel, -1, "Corefile gzip compression level");
3130 #define GZ_SUFFIX ".gz"
3131 #define GZ_SUFFIX_LEN 3
3134 static char corefilename[MAXPATHLEN] = {"%N.core"};
3135 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3136 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3137 sizeof(corefilename), "Process corefile name format string");
3140 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3141 * Expand the name described in corefilename, using name, uid, and pid
3142 * and open/create core file.
3143 * corefilename is a printf-like string, with three format specifiers:
3144 * %N name of process ("name")
3145 * %P process id (pid)
3147 * For example, "%N.core" is the default; they can be disabled completely
3148 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3149 * This is controlled by the sysctl variable kern.corefile (see above).
3152 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3153 int compress, struct vnode **vpp, char **namep)
3155 struct nameidata nd;
3158 char *hostname, *name;
3159 int indexpos, i, error, cmode, flags, oflags;
3162 format = corefilename;
3163 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3165 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3166 for (i = 0; format[i] != '\0'; i++) {
3167 switch (format[i]) {
3168 case '%': /* Format character */
3170 switch (format[i]) {
3172 sbuf_putc(&sb, '%');
3174 case 'H': /* hostname */
3175 if (hostname == NULL) {
3176 hostname = malloc(MAXHOSTNAMELEN,
3179 getcredhostname(td->td_ucred, hostname,
3181 sbuf_printf(&sb, "%s", hostname);
3183 case 'I': /* autoincrementing index */
3184 sbuf_printf(&sb, "0");
3185 indexpos = sbuf_len(&sb) - 1;
3187 case 'N': /* process name */
3188 sbuf_printf(&sb, "%s", comm);
3190 case 'P': /* process id */
3191 sbuf_printf(&sb, "%u", pid);
3193 case 'U': /* user id */
3194 sbuf_printf(&sb, "%u", uid);
3198 "Unknown format character %c in "
3199 "corename `%s'\n", format[i], format);
3204 sbuf_putc(&sb, format[i]);
3208 free(hostname, M_TEMP);
3209 #ifdef COMPRESS_USER_CORES
3211 sbuf_printf(&sb, GZ_SUFFIX);
3213 if (sbuf_error(&sb) != 0) {
3214 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3215 "long\n", (long)pid, comm, (u_long)uid);
3223 cmode = S_IRUSR | S_IWUSR;
3224 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3225 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3228 * If the core format has a %I in it, then we need to check
3229 * for existing corefiles before returning a name.
3230 * To do this we iterate over 0..num_cores to find a
3231 * non-existing core file name to use.
3233 if (indexpos != -1) {
3234 for (i = 0; i < num_cores; i++) {
3235 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3236 name[indexpos] = '0' + i;
3237 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3238 error = vn_open_cred(&nd, &flags, cmode, oflags,
3239 td->td_ucred, NULL);
3241 if (error == EEXIST)
3244 "pid %d (%s), uid (%u): Path `%s' failed "
3245 "on initial open test, error = %d\n",
3246 pid, comm, uid, name, error);
3252 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3253 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3254 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3258 audit_proc_coredump(td, name, error);
3263 NDFREE(&nd, NDF_ONLY_PNBUF);
3270 * Dump a process' core. The main routine does some
3271 * policy checking, and creates the name of the coredump;
3272 * then it passes on a vnode and a size limit to the process-specific
3273 * coredump routine if there is one; if there _is not_ one, it returns
3274 * ENOSYS; otherwise it returns the error from the process-specific routine.
3278 coredump(struct thread *td)
3280 struct proc *p = td->td_proc;
3281 struct ucred *cred = td->td_ucred;
3285 int error, error1, locked;
3287 char *name; /* name of corefile */
3291 #ifdef COMPRESS_USER_CORES
3292 compress = compress_user_cores;
3296 PROC_LOCK_ASSERT(p, MA_OWNED);
3297 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3298 _STOPEVENT(p, S_CORE, 0);
3300 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3301 (p->p_flag2 & P2_NOTRACE) != 0) {
3307 * Note that the bulk of limit checking is done after
3308 * the corefile is created. The exception is if the limit
3309 * for corefiles is 0, in which case we don't bother
3310 * creating the corefile at all. This layout means that
3311 * a corefile is truncated instead of not being created,
3312 * if it is larger than the limit.
3314 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3315 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3322 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress,
3327 /* Don't dump to non-regular files or files with links. */
3328 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3329 vattr.va_nlink != 1) {
3336 lf.l_whence = SEEK_SET;
3339 lf.l_type = F_WRLCK;
3340 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3342 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3343 lf.l_type = F_UNLCK;
3345 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3346 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3348 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3356 if (set_core_nodump_flag)
3357 vattr.va_flags = UF_NODUMP;
3358 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3359 VOP_SETATTR(vp, &vattr, cred);
3361 vn_finished_write(mp);
3363 p->p_acflag |= ACORE;
3366 if (p->p_sysent->sv_coredump != NULL) {
3367 error = p->p_sysent->sv_coredump(td, vp, limit,
3368 compress ? IMGACT_CORE_COMPRESS : 0);
3374 lf.l_type = F_UNLCK;
3375 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3378 error1 = vn_close(vp, FWRITE, cred, td);
3383 audit_proc_coredump(td, name, error);
3390 * Nonexistent system call-- signal process (may want to handle it). Flag
3391 * error in case process won't see signal immediately (blocked or ignored).
3393 #ifndef _SYS_SYSPROTO_H_
3402 struct nosys_args *args;
3404 struct proc *p = td->td_proc;
3407 tdsignal(td, SIGSYS);
3413 * Send a SIGIO or SIGURG signal to a process or process group using stored
3414 * credentials rather than those of the current process.
3417 pgsigio(sigiop, sig, checkctty)
3418 struct sigio **sigiop;
3422 struct sigio *sigio;
3424 ksiginfo_init(&ksi);
3425 ksi.ksi_signo = sig;
3426 ksi.ksi_code = SI_KERNEL;
3430 if (sigio == NULL) {
3434 if (sigio->sio_pgid > 0) {
3435 PROC_LOCK(sigio->sio_proc);
3436 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3437 kern_psignal(sigio->sio_proc, sig);
3438 PROC_UNLOCK(sigio->sio_proc);
3439 } else if (sigio->sio_pgid < 0) {
3442 PGRP_LOCK(sigio->sio_pgrp);
3443 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3445 if (p->p_state == PRS_NORMAL &&
3446 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3447 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3448 kern_psignal(p, sig);
3451 PGRP_UNLOCK(sigio->sio_pgrp);
3457 filt_sigattach(struct knote *kn)
3459 struct proc *p = curproc;
3461 kn->kn_ptr.p_proc = p;
3462 kn->kn_flags |= EV_CLEAR; /* automatically set */
3464 knlist_add(&p->p_klist, kn, 0);
3470 filt_sigdetach(struct knote *kn)
3472 struct proc *p = kn->kn_ptr.p_proc;
3474 knlist_remove(&p->p_klist, kn, 0);
3478 * signal knotes are shared with proc knotes, so we apply a mask to
3479 * the hint in order to differentiate them from process hints. This
3480 * could be avoided by using a signal-specific knote list, but probably
3481 * isn't worth the trouble.
3484 filt_signal(struct knote *kn, long hint)
3487 if (hint & NOTE_SIGNAL) {
3488 hint &= ~NOTE_SIGNAL;
3490 if (kn->kn_id == hint)
3493 return (kn->kn_data != 0);
3501 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3503 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3508 sigacts_free(struct sigacts *ps)
3511 if (refcount_release(&ps->ps_refcnt) == 0)
3513 mtx_destroy(&ps->ps_mtx);
3514 free(ps, M_SUBPROC);
3518 sigacts_hold(struct sigacts *ps)
3521 refcount_acquire(&ps->ps_refcnt);
3526 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3529 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3530 mtx_lock(&src->ps_mtx);
3531 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3532 mtx_unlock(&src->ps_mtx);
3536 sigacts_shared(struct sigacts *ps)
3539 return (ps->ps_refcnt > 1);