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
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8 * the permission of UNIX System Laboratories, Inc.
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14 * notice, this list of conditions and the following disclaimer.
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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"
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
50 #include <sys/condvar.h>
51 #include <sys/event.h>
52 #include <sys/fcntl.h>
53 #include <sys/imgact.h>
54 #include <sys/kernel.h>
56 #include <sys/ktrace.h>
58 #include <sys/malloc.h>
59 #include <sys/mutex.h>
60 #include <sys/namei.h>
62 #include <sys/posix4.h>
63 #include <sys/pioctl.h>
64 #include <sys/resourcevar.h>
67 #include <sys/sleepqueue.h>
71 #include <sys/syscallsubr.h>
72 #include <sys/sysctl.h>
73 #include <sys/sysent.h>
74 #include <sys/syslog.h>
75 #include <sys/sysproto.h>
76 #include <sys/timers.h>
77 #include <sys/unistd.h>
80 #include <vm/vm_extern.h>
85 #include <machine/cpu.h>
87 #include <security/audit/audit.h>
89 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
91 SDT_PROVIDER_DECLARE(proc);
92 SDT_PROBE_DEFINE(proc, kernel, , signal_send, signal-send);
93 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 0, "struct thread *");
94 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 1, "struct proc *");
95 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 2, "int");
96 SDT_PROBE_DEFINE(proc, kernel, , signal_clear, signal-clear);
97 SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 0, "int");
98 SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 1, "ksiginfo_t *");
99 SDT_PROBE_DEFINE(proc, kernel, , signal_discard, signal-discard);
100 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 0, "struct thread *");
101 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 1, "struct proc *");
102 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 2, "int");
104 static int coredump(struct thread *);
105 static char *expand_name(const char *, uid_t, pid_t, struct thread *, int);
106 static int killpg1(struct thread *td, int sig, int pgid, int all,
108 static int issignal(struct thread *td, int stop_allowed);
109 static int sigprop(int sig);
110 static int tdsendsignal(struct proc *p, struct thread *td, int sig,
112 static void tdsigwakeup(struct thread *, int, sig_t, int);
113 static void sig_suspend_threads(struct thread *, struct proc *, int);
114 static int filt_sigattach(struct knote *kn);
115 static void filt_sigdetach(struct knote *kn);
116 static int filt_signal(struct knote *kn, long hint);
117 static struct thread *sigtd(struct proc *p, int sig, int prop);
118 static void sigqueue_start(void);
120 static uma_zone_t ksiginfo_zone = NULL;
121 struct filterops sig_filtops = {
123 .f_attach = filt_sigattach,
124 .f_detach = filt_sigdetach,
125 .f_event = filt_signal,
128 static int kern_logsigexit = 1;
129 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
131 "Log processes quitting on abnormal signals to syslog(3)");
133 static int kern_forcesigexit = 1;
134 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
135 &kern_forcesigexit, 0, "Force trap signal to be handled");
137 SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0, "POSIX real time signal");
139 static int max_pending_per_proc = 128;
140 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
141 &max_pending_per_proc, 0, "Max pending signals per proc");
143 static int preallocate_siginfo = 1024;
144 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
145 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
146 &preallocate_siginfo, 0, "Preallocated signal memory size");
148 static int signal_overflow = 0;
149 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
150 &signal_overflow, 0, "Number of signals overflew");
152 static int signal_alloc_fail = 0;
153 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
154 &signal_alloc_fail, 0, "signals failed to be allocated");
156 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
159 * Policy -- Can ucred cr1 send SIGIO to process cr2?
160 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
161 * in the right situations.
163 #define CANSIGIO(cr1, cr2) \
164 ((cr1)->cr_uid == 0 || \
165 (cr1)->cr_ruid == (cr2)->cr_ruid || \
166 (cr1)->cr_uid == (cr2)->cr_ruid || \
167 (cr1)->cr_ruid == (cr2)->cr_uid || \
168 (cr1)->cr_uid == (cr2)->cr_uid)
170 static int sugid_coredump;
171 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
172 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
174 static int do_coredump = 1;
175 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
176 &do_coredump, 0, "Enable/Disable coredumps");
178 static int set_core_nodump_flag = 0;
179 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
180 0, "Enable setting the NODUMP flag on coredump files");
183 * Signal properties and actions.
184 * The array below categorizes the signals and their default actions
185 * according to the following properties:
187 #define SA_KILL 0x01 /* terminates process by default */
188 #define SA_CORE 0x02 /* ditto and coredumps */
189 #define SA_STOP 0x04 /* suspend process */
190 #define SA_TTYSTOP 0x08 /* ditto, from tty */
191 #define SA_IGNORE 0x10 /* ignore by default */
192 #define SA_CONT 0x20 /* continue if suspended */
193 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
194 #define SA_PROC 0x80 /* deliverable to any thread */
196 static int sigproptbl[NSIG] = {
197 SA_KILL|SA_PROC, /* SIGHUP */
198 SA_KILL|SA_PROC, /* SIGINT */
199 SA_KILL|SA_CORE|SA_PROC, /* SIGQUIT */
200 SA_KILL|SA_CORE, /* SIGILL */
201 SA_KILL|SA_CORE, /* SIGTRAP */
202 SA_KILL|SA_CORE, /* SIGABRT */
203 SA_KILL|SA_CORE|SA_PROC, /* SIGEMT */
204 SA_KILL|SA_CORE, /* SIGFPE */
205 SA_KILL|SA_PROC, /* SIGKILL */
206 SA_KILL|SA_CORE, /* SIGBUS */
207 SA_KILL|SA_CORE, /* SIGSEGV */
208 SA_KILL|SA_CORE, /* SIGSYS */
209 SA_KILL|SA_PROC, /* SIGPIPE */
210 SA_KILL|SA_PROC, /* SIGALRM */
211 SA_KILL|SA_PROC, /* SIGTERM */
212 SA_IGNORE|SA_PROC, /* SIGURG */
213 SA_STOP|SA_PROC, /* SIGSTOP */
214 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTSTP */
215 SA_IGNORE|SA_CONT|SA_PROC, /* SIGCONT */
216 SA_IGNORE|SA_PROC, /* SIGCHLD */
217 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTIN */
218 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTOU */
219 SA_IGNORE|SA_PROC, /* SIGIO */
220 SA_KILL, /* SIGXCPU */
221 SA_KILL, /* SIGXFSZ */
222 SA_KILL|SA_PROC, /* SIGVTALRM */
223 SA_KILL|SA_PROC, /* SIGPROF */
224 SA_IGNORE|SA_PROC, /* SIGWINCH */
225 SA_IGNORE|SA_PROC, /* SIGINFO */
226 SA_KILL|SA_PROC, /* SIGUSR1 */
227 SA_KILL|SA_PROC, /* SIGUSR2 */
230 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
235 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
236 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
237 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
238 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
239 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
240 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
244 ksiginfo_alloc(int wait)
251 if (ksiginfo_zone != NULL)
252 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
257 ksiginfo_free(ksiginfo_t *ksi)
259 uma_zfree(ksiginfo_zone, ksi);
263 ksiginfo_tryfree(ksiginfo_t *ksi)
265 if (!(ksi->ksi_flags & KSI_EXT)) {
266 uma_zfree(ksiginfo_zone, ksi);
273 sigqueue_init(sigqueue_t *list, struct proc *p)
275 SIGEMPTYSET(list->sq_signals);
276 SIGEMPTYSET(list->sq_kill);
277 TAILQ_INIT(&list->sq_list);
279 list->sq_flags = SQ_INIT;
283 * Get a signal's ksiginfo.
285 * 0 - signal not found
286 * others - signal number
289 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
291 struct proc *p = sq->sq_proc;
292 struct ksiginfo *ksi, *next;
295 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
297 if (!SIGISMEMBER(sq->sq_signals, signo))
300 if (SIGISMEMBER(sq->sq_kill, signo)) {
302 SIGDELSET(sq->sq_kill, signo);
305 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
306 if (ksi->ksi_signo == signo) {
308 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
309 ksi->ksi_sigq = NULL;
310 ksiginfo_copy(ksi, si);
311 if (ksiginfo_tryfree(ksi) && p != NULL)
320 SIGDELSET(sq->sq_signals, signo);
321 si->ksi_signo = signo;
326 sigqueue_take(ksiginfo_t *ksi)
332 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
336 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
337 ksi->ksi_sigq = NULL;
338 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
341 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
342 kp = TAILQ_NEXT(kp, ksi_link)) {
343 if (kp->ksi_signo == ksi->ksi_signo)
346 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
347 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
351 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
353 struct proc *p = sq->sq_proc;
354 struct ksiginfo *ksi;
357 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
359 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
360 SIGADDSET(sq->sq_kill, signo);
364 /* directly insert the ksi, don't copy it */
365 if (si->ksi_flags & KSI_INS) {
366 if (si->ksi_flags & KSI_HEAD)
367 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
369 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
374 if (__predict_false(ksiginfo_zone == NULL)) {
375 SIGADDSET(sq->sq_kill, signo);
379 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
382 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
388 ksiginfo_copy(si, ksi);
389 ksi->ksi_signo = signo;
390 if (si->ksi_flags & KSI_HEAD)
391 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
393 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
397 if ((si->ksi_flags & KSI_TRAP) != 0 ||
398 (si->ksi_flags & KSI_SIGQ) == 0) {
400 SIGADDSET(sq->sq_kill, signo);
409 SIGADDSET(sq->sq_signals, signo);
414 sigqueue_flush(sigqueue_t *sq)
416 struct proc *p = sq->sq_proc;
419 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
422 PROC_LOCK_ASSERT(p, MA_OWNED);
424 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
425 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
426 ksi->ksi_sigq = NULL;
427 if (ksiginfo_tryfree(ksi) && p != NULL)
431 SIGEMPTYSET(sq->sq_signals);
432 SIGEMPTYSET(sq->sq_kill);
436 sigqueue_collect_set(sigqueue_t *sq, sigset_t *set)
440 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
442 TAILQ_FOREACH(ksi, &sq->sq_list, ksi_link)
443 SIGADDSET(*set, ksi->ksi_signo);
444 SIGSETOR(*set, sq->sq_kill);
448 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, sigset_t *setp)
451 struct proc *p1, *p2;
452 ksiginfo_t *ksi, *next;
454 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
455 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
457 * make a copy, this allows setp to point to src or dst
458 * sq_signals without trouble.
463 /* Move siginfo to target list */
464 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
465 if (SIGISMEMBER(set, ksi->ksi_signo)) {
466 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
469 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
476 /* Move pending bits to target list */
479 SIGSETOR(dst->sq_kill, tmp);
480 SIGSETNAND(src->sq_kill, tmp);
482 tmp = src->sq_signals;
484 SIGSETOR(dst->sq_signals, tmp);
485 SIGSETNAND(src->sq_signals, tmp);
487 /* Finally, rescan src queue and set pending bits for it */
488 sigqueue_collect_set(src, &src->sq_signals);
492 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
497 SIGADDSET(set, signo);
498 sigqueue_move_set(src, dst, &set);
502 sigqueue_delete_set(sigqueue_t *sq, sigset_t *set)
504 struct proc *p = sq->sq_proc;
505 ksiginfo_t *ksi, *next;
507 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
509 /* Remove siginfo queue */
510 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
511 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
512 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
513 ksi->ksi_sigq = NULL;
514 if (ksiginfo_tryfree(ksi) && p != NULL)
518 SIGSETNAND(sq->sq_kill, *set);
519 SIGSETNAND(sq->sq_signals, *set);
520 /* Finally, rescan queue and set pending bits for it */
521 sigqueue_collect_set(sq, &sq->sq_signals);
525 sigqueue_delete(sigqueue_t *sq, int signo)
530 SIGADDSET(set, signo);
531 sigqueue_delete_set(sq, &set);
534 /* Remove a set of signals for a process */
536 sigqueue_delete_set_proc(struct proc *p, sigset_t *set)
541 PROC_LOCK_ASSERT(p, MA_OWNED);
543 sigqueue_init(&worklist, NULL);
544 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
546 FOREACH_THREAD_IN_PROC(p, td0)
547 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
549 sigqueue_flush(&worklist);
553 sigqueue_delete_proc(struct proc *p, int signo)
558 SIGADDSET(set, signo);
559 sigqueue_delete_set_proc(p, &set);
563 sigqueue_delete_stopmask_proc(struct proc *p)
568 SIGADDSET(set, SIGSTOP);
569 SIGADDSET(set, SIGTSTP);
570 SIGADDSET(set, SIGTTIN);
571 SIGADDSET(set, SIGTTOU);
572 sigqueue_delete_set_proc(p, &set);
576 * Determine signal that should be delivered to process p, the current
577 * process, 0 if none. If there is a pending stop signal with default
578 * action, the process stops in issignal().
581 cursig(struct thread *td, int stop_allowed)
583 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
584 KASSERT(stop_allowed == SIG_STOP_ALLOWED ||
585 stop_allowed == SIG_STOP_NOT_ALLOWED, ("cursig: stop_allowed"));
586 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
587 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
588 return (SIGPENDING(td) ? issignal(td, stop_allowed) : 0);
592 * Arrange for ast() to handle unmasked pending signals on return to user
593 * mode. This must be called whenever a signal is added to td_sigqueue or
594 * unmasked in td_sigmask.
597 signotify(struct thread *td)
603 PROC_LOCK_ASSERT(p, MA_OWNED);
605 if (SIGPENDING(td)) {
607 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
613 sigonstack(size_t sp)
615 struct thread *td = curthread;
617 return ((td->td_pflags & TDP_ALTSTACK) ?
618 #if defined(COMPAT_43)
619 ((td->td_sigstk.ss_size == 0) ?
620 (td->td_sigstk.ss_flags & SS_ONSTACK) :
621 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
623 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
632 if (sig > 0 && sig < NSIG)
633 return (sigproptbl[_SIG_IDX(sig)]);
638 sig_ffs(sigset_t *set)
642 for (i = 0; i < _SIG_WORDS; i++)
644 return (ffs(set->__bits[i]) + (i * 32));
655 kern_sigaction(td, sig, act, oact, flags)
658 struct sigaction *act, *oact;
662 struct proc *p = td->td_proc;
664 if (!_SIG_VALID(sig))
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 (act->sa_flags & 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 (!(act->sa_flags & SA_RESTART))
715 SIGADDSET(ps->ps_sigintr, sig);
717 SIGDELSET(ps->ps_sigintr, sig);
718 if (act->sa_flags & SA_ONSTACK)
719 SIGADDSET(ps->ps_sigonstack, sig);
721 SIGDELSET(ps->ps_sigonstack, sig);
722 if (act->sa_flags & SA_RESETHAND)
723 SIGADDSET(ps->ps_sigreset, sig);
725 SIGDELSET(ps->ps_sigreset, sig);
726 if (act->sa_flags & 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;
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);
930 mtx_unlock(&ps->ps_mtx);
935 * Reset signals for an exec of the specified process.
938 execsigs(struct proc *p)
945 * Reset caught signals. Held signals remain held
946 * through td_sigmask (unless they were caught,
947 * and are now ignored by default).
949 PROC_LOCK_ASSERT(p, MA_OWNED);
950 td = FIRST_THREAD_IN_PROC(p);
952 mtx_lock(&ps->ps_mtx);
953 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
954 sig = sig_ffs(&ps->ps_sigcatch);
955 SIGDELSET(ps->ps_sigcatch, sig);
956 if (sigprop(sig) & SA_IGNORE) {
958 SIGADDSET(ps->ps_sigignore, sig);
959 sigqueue_delete_proc(p, sig);
961 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
964 * Reset stack state to the user stack.
965 * Clear set of signals caught on the signal stack.
967 td->td_sigstk.ss_flags = SS_DISABLE;
968 td->td_sigstk.ss_size = 0;
969 td->td_sigstk.ss_sp = 0;
970 td->td_pflags &= ~TDP_ALTSTACK;
972 * Reset no zombies if child dies flag as Solaris does.
974 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
975 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
976 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
977 mtx_unlock(&ps->ps_mtx);
983 * Manipulate signal mask.
986 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
989 sigset_t new_block, oset1;
994 if (!(flags & SIGPROCMASK_PROC_LOCKED))
997 *oset = td->td_sigmask;
1000 SIGEMPTYSET(new_block);
1005 oset1 = td->td_sigmask;
1006 SIGSETOR(td->td_sigmask, *set);
1007 new_block = td->td_sigmask;
1008 SIGSETNAND(new_block, oset1);
1011 SIGSETNAND(td->td_sigmask, *set);
1016 oset1 = td->td_sigmask;
1017 if (flags & SIGPROCMASK_OLD)
1018 SIGSETLO(td->td_sigmask, *set);
1020 td->td_sigmask = *set;
1021 new_block = td->td_sigmask;
1022 SIGSETNAND(new_block, oset1);
1032 * The new_block set contains signals that were not previously
1033 * blocked, but are blocked now.
1035 * In case we block any signal that was not previously blocked
1036 * for td, and process has the signal pending, try to schedule
1037 * signal delivery to some thread that does not block the signal,
1038 * possibly waking it up.
1040 if (p->p_numthreads != 1)
1041 reschedule_signals(p, new_block, flags);
1043 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1048 #ifndef _SYS_SYSPROTO_H_
1049 struct sigprocmask_args {
1051 const sigset_t *set;
1056 sigprocmask(td, uap)
1057 register struct thread *td;
1058 struct sigprocmask_args *uap;
1061 sigset_t *setp, *osetp;
1064 setp = (uap->set != NULL) ? &set : NULL;
1065 osetp = (uap->oset != NULL) ? &oset : NULL;
1067 error = copyin(uap->set, setp, sizeof(set));
1071 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1072 if (osetp && !error) {
1073 error = copyout(osetp, uap->oset, sizeof(oset));
1078 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1079 #ifndef _SYS_SYSPROTO_H_
1080 struct osigprocmask_args {
1086 osigprocmask(td, uap)
1087 register struct thread *td;
1088 struct osigprocmask_args *uap;
1093 OSIG2SIG(uap->mask, set);
1094 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1095 SIG2OSIG(oset, td->td_retval[0]);
1098 #endif /* COMPAT_43 */
1101 sigwait(struct thread *td, struct sigwait_args *uap)
1107 error = copyin(uap->set, &set, sizeof(set));
1109 td->td_retval[0] = error;
1113 error = kern_sigtimedwait(td, set, &ksi, NULL);
1115 if (error == ERESTART)
1117 td->td_retval[0] = error;
1121 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1122 td->td_retval[0] = error;
1127 sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1130 struct timespec *timeout;
1136 error = copyin(uap->timeout, &ts, sizeof(ts));
1144 error = copyin(uap->set, &set, sizeof(set));
1148 error = kern_sigtimedwait(td, set, &ksi, timeout);
1153 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1156 td->td_retval[0] = ksi.ksi_signo;
1161 sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1167 error = copyin(uap->set, &set, sizeof(set));
1171 error = kern_sigtimedwait(td, set, &ksi, NULL);
1176 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1179 td->td_retval[0] = ksi.ksi_signo;
1184 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1185 struct timespec *timeout)
1190 int error, sig, hz, i, timevalid = 0;
1191 struct timespec rts, ets, ts;
1199 SIG_CANTMASK(waitset);
1203 savedmask = td->td_sigmask;
1205 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1207 getnanouptime(&rts);
1209 timespecadd(&ets, timeout);
1214 for (i = 1; i <= _SIG_MAXSIG; ++i) {
1215 if (!SIGISMEMBER(waitset, i))
1217 if (!SIGISMEMBER(td->td_sigqueue.sq_signals, i)) {
1218 if (SIGISMEMBER(p->p_sigqueue.sq_signals, i)) {
1219 sigqueue_move(&p->p_sigqueue,
1220 &td->td_sigqueue, i);
1225 SIGFILLSET(td->td_sigmask);
1226 SIG_CANTMASK(td->td_sigmask);
1227 SIGDELSET(td->td_sigmask, i);
1228 mtx_lock(&ps->ps_mtx);
1229 sig = cursig(td, SIG_STOP_ALLOWED);
1230 mtx_unlock(&ps->ps_mtx);
1235 * Because cursig() may have stopped current thread,
1236 * after it is resumed, things may have already been
1237 * changed, it should rescan any pending signals.
1247 * POSIX says this must be checked after looking for pending
1255 getnanouptime(&rts);
1256 if (timespeccmp(&rts, &ets, >=)) {
1261 timespecsub(&ts, &rts);
1262 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1267 td->td_sigmask = savedmask;
1268 SIGSETNAND(td->td_sigmask, waitset);
1270 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz);
1272 if (error == ERESTART) {
1273 /* timeout can not be restarted. */
1275 } else if (error == EAGAIN) {
1276 /* will calculate timeout by ourself. */
1283 td->td_sigmask = savedmask;
1287 sigqueue_get(&td->td_sigqueue, sig, ksi);
1288 ksi->ksi_signo = sig;
1290 SDT_PROBE(proc, kernel, , signal_clear, sig, ksi, 0, 0, 0);
1292 if (ksi->ksi_code == SI_TIMER)
1293 itimer_accept(p, ksi->ksi_timerid, ksi);
1297 if (KTRPOINT(td, KTR_PSIG)) {
1300 mtx_lock(&ps->ps_mtx);
1301 action = ps->ps_sigact[_SIG_IDX(sig)];
1302 mtx_unlock(&ps->ps_mtx);
1303 ktrpsig(sig, action, &td->td_sigmask, 0);
1313 #ifndef _SYS_SYSPROTO_H_
1314 struct sigpending_args {
1321 struct sigpending_args *uap;
1323 struct proc *p = td->td_proc;
1327 pending = p->p_sigqueue.sq_signals;
1328 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1330 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1333 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1334 #ifndef _SYS_SYSPROTO_H_
1335 struct osigpending_args {
1340 osigpending(td, uap)
1342 struct osigpending_args *uap;
1344 struct proc *p = td->td_proc;
1348 pending = p->p_sigqueue.sq_signals;
1349 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1351 SIG2OSIG(pending, td->td_retval[0]);
1354 #endif /* COMPAT_43 */
1356 #if defined(COMPAT_43)
1358 * Generalized interface signal handler, 4.3-compatible.
1360 #ifndef _SYS_SYSPROTO_H_
1361 struct osigvec_args {
1371 register struct osigvec_args *uap;
1374 struct sigaction nsa, osa;
1375 register struct sigaction *nsap, *osap;
1378 if (uap->signum <= 0 || uap->signum >= ONSIG)
1380 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1381 osap = (uap->osv != NULL) ? &osa : NULL;
1383 error = copyin(uap->nsv, &vec, sizeof(vec));
1386 nsap->sa_handler = vec.sv_handler;
1387 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1388 nsap->sa_flags = vec.sv_flags;
1389 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1391 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1392 if (osap && !error) {
1393 vec.sv_handler = osap->sa_handler;
1394 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1395 vec.sv_flags = osap->sa_flags;
1396 vec.sv_flags &= ~SA_NOCLDWAIT;
1397 vec.sv_flags ^= SA_RESTART;
1398 error = copyout(&vec, uap->osv, sizeof(vec));
1403 #ifndef _SYS_SYSPROTO_H_
1404 struct osigblock_args {
1410 register struct thread *td;
1411 struct osigblock_args *uap;
1415 OSIG2SIG(uap->mask, set);
1416 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1417 SIG2OSIG(oset, td->td_retval[0]);
1421 #ifndef _SYS_SYSPROTO_H_
1422 struct osigsetmask_args {
1427 osigsetmask(td, uap)
1429 struct osigsetmask_args *uap;
1433 OSIG2SIG(uap->mask, set);
1434 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1435 SIG2OSIG(oset, td->td_retval[0]);
1438 #endif /* COMPAT_43 */
1441 * Suspend calling thread until signal, providing mask to be set in the
1444 #ifndef _SYS_SYSPROTO_H_
1445 struct sigsuspend_args {
1446 const sigset_t *sigmask;
1453 struct sigsuspend_args *uap;
1458 error = copyin(uap->sigmask, &mask, sizeof(mask));
1461 return (kern_sigsuspend(td, mask));
1465 kern_sigsuspend(struct thread *td, sigset_t mask)
1467 struct proc *p = td->td_proc;
1471 * When returning from sigsuspend, we want
1472 * the old mask to be restored after the
1473 * signal handler has finished. Thus, we
1474 * save it here and mark the sigacts structure
1478 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1479 SIGPROCMASK_PROC_LOCKED);
1480 td->td_pflags |= TDP_OLDMASK;
1483 * Process signals now. Otherwise, we can get spurious wakeup
1484 * due to signal entered process queue, but delivered to other
1485 * thread. But sigsuspend should return only on signal
1488 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1489 for (has_sig = 0; !has_sig;) {
1490 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1493 thread_suspend_check(0);
1494 mtx_lock(&p->p_sigacts->ps_mtx);
1495 while ((sig = cursig(td, SIG_STOP_ALLOWED)) != 0)
1496 has_sig += postsig(sig);
1497 mtx_unlock(&p->p_sigacts->ps_mtx);
1500 return (EJUSTRETURN);
1503 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1505 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1506 * convention: libc stub passes mask, not pointer, to save a copyin.
1508 #ifndef _SYS_SYSPROTO_H_
1509 struct osigsuspend_args {
1515 osigsuspend(td, uap)
1517 struct osigsuspend_args *uap;
1521 OSIG2SIG(uap->mask, mask);
1522 return (kern_sigsuspend(td, mask));
1524 #endif /* COMPAT_43 */
1526 #if defined(COMPAT_43)
1527 #ifndef _SYS_SYSPROTO_H_
1528 struct osigstack_args {
1529 struct sigstack *nss;
1530 struct sigstack *oss;
1537 register struct osigstack_args *uap;
1539 struct sigstack nss, oss;
1542 if (uap->nss != NULL) {
1543 error = copyin(uap->nss, &nss, sizeof(nss));
1547 oss.ss_sp = td->td_sigstk.ss_sp;
1548 oss.ss_onstack = sigonstack(cpu_getstack(td));
1549 if (uap->nss != NULL) {
1550 td->td_sigstk.ss_sp = nss.ss_sp;
1551 td->td_sigstk.ss_size = 0;
1552 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1553 td->td_pflags |= TDP_ALTSTACK;
1555 if (uap->oss != NULL)
1556 error = copyout(&oss, uap->oss, sizeof(oss));
1560 #endif /* COMPAT_43 */
1562 #ifndef _SYS_SYSPROTO_H_
1563 struct sigaltstack_args {
1570 sigaltstack(td, uap)
1572 register struct sigaltstack_args *uap;
1577 if (uap->ss != NULL) {
1578 error = copyin(uap->ss, &ss, sizeof(ss));
1582 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1583 (uap->oss != NULL) ? &oss : NULL);
1586 if (uap->oss != NULL)
1587 error = copyout(&oss, uap->oss, sizeof(stack_t));
1592 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1594 struct proc *p = td->td_proc;
1597 oonstack = sigonstack(cpu_getstack(td));
1600 *oss = td->td_sigstk;
1601 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1602 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1608 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1610 if (!(ss->ss_flags & SS_DISABLE)) {
1611 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1614 td->td_sigstk = *ss;
1615 td->td_pflags |= TDP_ALTSTACK;
1617 td->td_pflags &= ~TDP_ALTSTACK;
1624 * Common code for kill process group/broadcast kill.
1625 * cp is calling process.
1628 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1638 sx_slock(&allproc_lock);
1639 FOREACH_PROC_IN_SYSTEM(p) {
1641 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1642 p == td->td_proc || p->p_state == PRS_NEW) {
1646 if (p_cansignal(td, p, sig) == 0) {
1649 pksignal(p, sig, ksi);
1653 sx_sunlock(&allproc_lock);
1655 sx_slock(&proctree_lock);
1658 * zero pgid means send to my process group.
1660 pgrp = td->td_proc->p_pgrp;
1663 pgrp = pgfind(pgid);
1665 sx_sunlock(&proctree_lock);
1669 sx_sunlock(&proctree_lock);
1670 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1672 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1673 p->p_state == PRS_NEW ) {
1677 if (p_cansignal(td, p, sig) == 0) {
1680 pksignal(p, sig, ksi);
1686 return (nfound ? 0 : ESRCH);
1689 #ifndef _SYS_SYSPROTO_H_
1697 kill(struct thread *td, struct kill_args *uap)
1703 AUDIT_ARG_SIGNUM(uap->signum);
1704 AUDIT_ARG_PID(uap->pid);
1705 if ((u_int)uap->signum > _SIG_MAXSIG)
1708 ksiginfo_init(&ksi);
1709 ksi.ksi_signo = uap->signum;
1710 ksi.ksi_code = SI_USER;
1711 ksi.ksi_pid = td->td_proc->p_pid;
1712 ksi.ksi_uid = td->td_ucred->cr_ruid;
1715 /* kill single process */
1716 if ((p = pfind(uap->pid)) == NULL) {
1717 if ((p = zpfind(uap->pid)) == NULL)
1720 AUDIT_ARG_PROCESS(p);
1721 error = p_cansignal(td, p, uap->signum);
1722 if (error == 0 && uap->signum)
1723 pksignal(p, uap->signum, &ksi);
1728 case -1: /* broadcast signal */
1729 return (killpg1(td, uap->signum, 0, 1, &ksi));
1730 case 0: /* signal own process group */
1731 return (killpg1(td, uap->signum, 0, 0, &ksi));
1732 default: /* negative explicit process group */
1733 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1738 #if defined(COMPAT_43)
1739 #ifndef _SYS_SYSPROTO_H_
1740 struct okillpg_args {
1747 okillpg(struct thread *td, struct okillpg_args *uap)
1751 AUDIT_ARG_SIGNUM(uap->signum);
1752 AUDIT_ARG_PID(uap->pgid);
1753 if ((u_int)uap->signum > _SIG_MAXSIG)
1756 ksiginfo_init(&ksi);
1757 ksi.ksi_signo = uap->signum;
1758 ksi.ksi_code = SI_USER;
1759 ksi.ksi_pid = td->td_proc->p_pid;
1760 ksi.ksi_uid = td->td_ucred->cr_ruid;
1761 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1763 #endif /* COMPAT_43 */
1765 #ifndef _SYS_SYSPROTO_H_
1766 struct sigqueue_args {
1769 /* union sigval */ void *value;
1773 sigqueue(struct thread *td, struct sigqueue_args *uap)
1779 if ((u_int)uap->signum > _SIG_MAXSIG)
1783 * Specification says sigqueue can only send signal to
1789 if ((p = pfind(uap->pid)) == NULL) {
1790 if ((p = zpfind(uap->pid)) == NULL)
1793 error = p_cansignal(td, p, uap->signum);
1794 if (error == 0 && uap->signum != 0) {
1795 ksiginfo_init(&ksi);
1796 ksi.ksi_flags = KSI_SIGQ;
1797 ksi.ksi_signo = uap->signum;
1798 ksi.ksi_code = SI_QUEUE;
1799 ksi.ksi_pid = td->td_proc->p_pid;
1800 ksi.ksi_uid = td->td_ucred->cr_ruid;
1801 ksi.ksi_value.sival_ptr = uap->value;
1802 error = pksignal(p, ksi.ksi_signo, &ksi);
1809 * Send a signal to a process group.
1812 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1817 sx_slock(&proctree_lock);
1818 pgrp = pgfind(pgid);
1819 sx_sunlock(&proctree_lock);
1821 pgsignal(pgrp, sig, 0, ksi);
1828 * Send a signal to a process group. If checktty is 1,
1829 * limit to members which have a controlling terminal.
1832 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1837 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1838 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1840 if (checkctty == 0 || p->p_flag & P_CONTROLT)
1841 pksignal(p, sig, ksi);
1848 * Send a signal caused by a trap to the current thread. If it will be
1849 * caught immediately, deliver it with correct code. Otherwise, post it
1853 trapsignal(struct thread *td, ksiginfo_t *ksi)
1862 sig = ksi->ksi_signo;
1863 code = ksi->ksi_code;
1864 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1868 mtx_lock(&ps->ps_mtx);
1869 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1870 !SIGISMEMBER(td->td_sigmask, sig)) {
1871 td->td_ru.ru_nsignals++;
1873 if (KTRPOINT(curthread, KTR_PSIG))
1874 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1875 &td->td_sigmask, code);
1877 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1878 ksi, &td->td_sigmask);
1879 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1880 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1881 SIGADDSET(mask, sig);
1882 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1883 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1884 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1886 * See kern_sigaction() for origin of this code.
1888 SIGDELSET(ps->ps_sigcatch, sig);
1889 if (sig != SIGCONT &&
1890 sigprop(sig) & SA_IGNORE)
1891 SIGADDSET(ps->ps_sigignore, sig);
1892 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1894 mtx_unlock(&ps->ps_mtx);
1897 * Avoid a possible infinite loop if the thread
1898 * masking the signal or process is ignoring the
1901 if (kern_forcesigexit &&
1902 (SIGISMEMBER(td->td_sigmask, sig) ||
1903 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1904 SIGDELSET(td->td_sigmask, sig);
1905 SIGDELSET(ps->ps_sigcatch, sig);
1906 SIGDELSET(ps->ps_sigignore, sig);
1907 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1909 mtx_unlock(&ps->ps_mtx);
1910 p->p_code = code; /* XXX for core dump/debugger */
1911 p->p_sig = sig; /* XXX to verify code */
1912 tdsendsignal(p, td, sig, ksi);
1917 static struct thread *
1918 sigtd(struct proc *p, int sig, int prop)
1920 struct thread *td, *signal_td;
1922 PROC_LOCK_ASSERT(p, MA_OWNED);
1925 * Check if current thread can handle the signal without
1926 * switching context to another thread.
1928 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1931 FOREACH_THREAD_IN_PROC(p, td) {
1932 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1937 if (signal_td == NULL)
1938 signal_td = FIRST_THREAD_IN_PROC(p);
1943 * Send the signal to the process. If the signal has an action, the action
1944 * is usually performed by the target process rather than the caller; we add
1945 * the signal to the set of pending signals for the process.
1948 * o When a stop signal is sent to a sleeping process that takes the
1949 * default action, the process is stopped without awakening it.
1950 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1951 * regardless of the signal action (eg, blocked or ignored).
1953 * Other ignored signals are discarded immediately.
1955 * NB: This function may be entered from the debugger via the "kill" DDB
1956 * command. There is little that can be done to mitigate the possibly messy
1957 * side effects of this unwise possibility.
1960 psignal(struct proc *p, int sig)
1964 ksiginfo_init(&ksi);
1965 ksi.ksi_signo = sig;
1966 ksi.ksi_code = SI_KERNEL;
1967 (void) tdsendsignal(p, NULL, sig, &ksi);
1971 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
1974 return (tdsendsignal(p, NULL, sig, ksi));
1978 psignal_event(struct proc *p, struct sigevent *sigev, ksiginfo_t *ksi)
1980 struct thread *td = NULL;
1982 PROC_LOCK_ASSERT(p, MA_OWNED);
1984 KASSERT(!KSI_ONQ(ksi), ("psignal_event: ksi on queue"));
1987 * ksi_code and other fields should be set before
1988 * calling this function.
1990 ksi->ksi_signo = sigev->sigev_signo;
1991 ksi->ksi_value = sigev->sigev_value;
1992 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
1993 td = thread_find(p, sigev->sigev_notify_thread_id);
1997 return (tdsendsignal(p, td, ksi->ksi_signo, ksi));
2001 tdsignal(struct thread *td, int sig)
2005 ksiginfo_init(&ksi);
2006 ksi.ksi_signo = sig;
2007 ksi.ksi_code = SI_KERNEL;
2008 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2012 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2015 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2019 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2022 sigqueue_t *sigqueue;
2029 PROC_LOCK_ASSERT(p, MA_OWNED);
2031 if (!_SIG_VALID(sig))
2032 panic("%s(): invalid signal %d", __func__, sig);
2034 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2037 * IEEE Std 1003.1-2001: return success when killing a zombie.
2039 if (p->p_state == PRS_ZOMBIE) {
2040 if (ksi && (ksi->ksi_flags & KSI_INS))
2041 ksiginfo_tryfree(ksi);
2046 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2047 prop = sigprop(sig);
2050 td = sigtd(p, sig, prop);
2051 sigqueue = &p->p_sigqueue;
2053 KASSERT(td->td_proc == p, ("invalid thread"));
2054 sigqueue = &td->td_sigqueue;
2057 SDT_PROBE(proc, kernel, , signal_send, td, p, sig, 0, 0 );
2060 * If the signal is being ignored,
2061 * then we forget about it immediately.
2062 * (Note: we don't set SIGCONT in ps_sigignore,
2063 * and if it is set to SIG_IGN,
2064 * action will be SIG_DFL here.)
2066 mtx_lock(&ps->ps_mtx);
2067 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2068 SDT_PROBE(proc, kernel, , signal_discard, ps, td, sig, 0, 0 );
2070 mtx_unlock(&ps->ps_mtx);
2071 if (ksi && (ksi->ksi_flags & KSI_INS))
2072 ksiginfo_tryfree(ksi);
2075 if (SIGISMEMBER(td->td_sigmask, sig))
2077 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2081 if (SIGISMEMBER(ps->ps_sigintr, sig))
2085 mtx_unlock(&ps->ps_mtx);
2088 sigqueue_delete_stopmask_proc(p);
2089 else if (prop & SA_STOP) {
2091 * If sending a tty stop signal to a member of an orphaned
2092 * process group, discard the signal here if the action
2093 * is default; don't stop the process below if sleeping,
2094 * and don't clear any pending SIGCONT.
2096 if ((prop & SA_TTYSTOP) &&
2097 (p->p_pgrp->pg_jobc == 0) &&
2098 (action == SIG_DFL)) {
2099 if (ksi && (ksi->ksi_flags & KSI_INS))
2100 ksiginfo_tryfree(ksi);
2103 sigqueue_delete_proc(p, SIGCONT);
2104 if (p->p_flag & P_CONTINUED) {
2105 p->p_flag &= ~P_CONTINUED;
2106 PROC_LOCK(p->p_pptr);
2107 sigqueue_take(p->p_ksi);
2108 PROC_UNLOCK(p->p_pptr);
2112 ret = sigqueue_add(sigqueue, sig, ksi);
2117 * Defer further processing for signals which are held,
2118 * except that stopped processes must be continued by SIGCONT.
2120 if (action == SIG_HOLD &&
2121 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2124 * SIGKILL: Remove procfs STOPEVENTs.
2126 if (sig == SIGKILL) {
2127 /* from procfs_ioctl.c: PIOCBIC */
2129 /* from procfs_ioctl.c: PIOCCONT */
2134 * Some signals have a process-wide effect and a per-thread
2135 * component. Most processing occurs when the process next
2136 * tries to cross the user boundary, however there are some
2137 * times when processing needs to be done immediatly, such as
2138 * waking up threads so that they can cross the user boundary.
2139 * We try do the per-process part here.
2141 if (P_SHOULDSTOP(p)) {
2142 if (sig == SIGKILL) {
2144 * If traced process is already stopped,
2145 * then no further action is necessary.
2147 if (p->p_flag & P_TRACED)
2150 * SIGKILL sets process running.
2151 * It will die elsewhere.
2152 * All threads must be restarted.
2154 p->p_flag &= ~P_STOPPED_SIG;
2158 if (prop & SA_CONT) {
2160 * If traced process is already stopped,
2161 * then no further action is necessary.
2163 if (p->p_flag & P_TRACED)
2166 * If SIGCONT is default (or ignored), we continue the
2167 * process but don't leave the signal in sigqueue as
2168 * it has no further action. If SIGCONT is held, we
2169 * continue the process and leave the signal in
2170 * sigqueue. If the process catches SIGCONT, let it
2171 * handle the signal itself. If it isn't waiting on
2172 * an event, it goes back to run state.
2173 * Otherwise, process goes back to sleep state.
2175 p->p_flag &= ~P_STOPPED_SIG;
2177 if (p->p_numthreads == p->p_suspcount) {
2179 p->p_flag |= P_CONTINUED;
2180 p->p_xstat = SIGCONT;
2181 PROC_LOCK(p->p_pptr);
2182 childproc_continued(p);
2183 PROC_UNLOCK(p->p_pptr);
2186 if (action == SIG_DFL) {
2187 thread_unsuspend(p);
2189 sigqueue_delete(sigqueue, sig);
2192 if (action == SIG_CATCH) {
2194 * The process wants to catch it so it needs
2195 * to run at least one thread, but which one?
2201 * The signal is not ignored or caught.
2203 thread_unsuspend(p);
2208 if (prop & SA_STOP) {
2210 * If traced process is already stopped,
2211 * then no further action is necessary.
2213 if (p->p_flag & P_TRACED)
2216 * Already stopped, don't need to stop again
2217 * (If we did the shell could get confused).
2218 * Just make sure the signal STOP bit set.
2220 p->p_flag |= P_STOPPED_SIG;
2221 sigqueue_delete(sigqueue, sig);
2226 * All other kinds of signals:
2227 * If a thread is sleeping interruptibly, simulate a
2228 * wakeup so that when it is continued it will be made
2229 * runnable and can look at the signal. However, don't make
2230 * the PROCESS runnable, leave it stopped.
2231 * It may run a bit until it hits a thread_suspend_check().
2236 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2237 wakeup_swapper = sleepq_abort(td, intrval);
2244 * Mutexes are short lived. Threads waiting on them will
2245 * hit thread_suspend_check() soon.
2247 } else if (p->p_state == PRS_NORMAL) {
2248 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2249 tdsigwakeup(td, sig, action, intrval);
2253 MPASS(action == SIG_DFL);
2255 if (prop & SA_STOP) {
2256 if (p->p_flag & P_PPWAIT)
2258 p->p_flag |= P_STOPPED_SIG;
2261 sig_suspend_threads(td, p, 1);
2262 if (p->p_numthreads == p->p_suspcount) {
2264 * only thread sending signal to another
2265 * process can reach here, if thread is sending
2266 * signal to its process, because thread does
2267 * not suspend itself here, p_numthreads
2268 * should never be equal to p_suspcount.
2272 sigqueue_delete_proc(p, p->p_xstat);
2278 /* Not in "NORMAL" state. discard the signal. */
2279 sigqueue_delete(sigqueue, sig);
2284 * The process is not stopped so we need to apply the signal to all the
2288 tdsigwakeup(td, sig, action, intrval);
2290 thread_unsuspend(p);
2293 /* If we jump here, proc slock should not be owned. */
2294 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2299 * The force of a signal has been directed against a single
2300 * thread. We need to see what we can do about knocking it
2301 * out of any sleep it may be in etc.
2304 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2306 struct proc *p = td->td_proc;
2311 PROC_LOCK_ASSERT(p, MA_OWNED);
2312 prop = sigprop(sig);
2317 * Bring the priority of a thread up if we want it to get
2318 * killed in this lifetime.
2320 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2321 sched_prio(td, PUSER);
2322 if (TD_ON_SLEEPQ(td)) {
2324 * If thread is sleeping uninterruptibly
2325 * we can't interrupt the sleep... the signal will
2326 * be noticed when the process returns through
2327 * trap() or syscall().
2329 if ((td->td_flags & TDF_SINTR) == 0)
2332 * If SIGCONT is default (or ignored) and process is
2333 * asleep, we are finished; the process should not
2336 if ((prop & SA_CONT) && action == SIG_DFL) {
2339 sigqueue_delete(&p->p_sigqueue, sig);
2341 * It may be on either list in this state.
2342 * Remove from both for now.
2344 sigqueue_delete(&td->td_sigqueue, sig);
2349 * Give low priority threads a better chance to run.
2351 if (td->td_priority > PUSER)
2352 sched_prio(td, PUSER);
2354 wakeup_swapper = sleepq_abort(td, intrval);
2357 * Other states do nothing with the signal immediately,
2358 * other than kicking ourselves if we are running.
2359 * It will either never be noticed, or noticed very soon.
2362 if (TD_IS_RUNNING(td) && td != curthread)
2374 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2379 PROC_LOCK_ASSERT(p, MA_OWNED);
2380 PROC_SLOCK_ASSERT(p, MA_OWNED);
2383 FOREACH_THREAD_IN_PROC(p, td2) {
2385 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2386 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2387 (td2->td_flags & TDF_SINTR)) {
2388 if (td2->td_flags & TDF_SBDRY) {
2389 if (TD_IS_SUSPENDED(td2))
2391 thread_unsuspend_one(td2);
2392 if (TD_ON_SLEEPQ(td2))
2394 sleepq_abort(td2, ERESTART);
2395 } else if (!TD_IS_SUSPENDED(td2)) {
2396 thread_suspend_one(td2);
2398 } else if (!TD_IS_SUSPENDED(td2)) {
2399 if (sending || td != td2)
2400 td2->td_flags |= TDF_ASTPENDING;
2402 if (TD_IS_RUNNING(td2) && td2 != td)
2403 forward_signal(td2);
2413 ptracestop(struct thread *td, int sig)
2415 struct proc *p = td->td_proc;
2417 PROC_LOCK_ASSERT(p, MA_OWNED);
2418 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2419 &p->p_mtx.lock_object, "Stopping for traced signal");
2421 td->td_dbgflags |= TDB_XSIG;
2424 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2425 if (p->p_flag & P_SINGLE_EXIT) {
2426 td->td_dbgflags &= ~TDB_XSIG;
2431 * Just make wait() to work, the last stopped thread
2436 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2437 sig_suspend_threads(td, p, 0);
2439 thread_suspend_switch(td);
2440 if (!(p->p_flag & P_TRACED)) {
2443 if (td->td_dbgflags & TDB_SUSPEND) {
2444 if (p->p_flag & P_SINGLE_EXIT)
2450 return (td->td_xsig);
2454 reschedule_signals(struct proc *p, sigset_t block, int flags)
2460 PROC_LOCK_ASSERT(p, MA_OWNED);
2463 for (i = 1; !SIGISEMPTY(block); i++) {
2464 if (!SIGISMEMBER(block, i))
2466 SIGDELSET(block, i);
2467 if (!SIGISMEMBER(p->p_siglist, i))
2470 td = sigtd(p, i, 0);
2472 if (!(flags & SIGPROCMASK_PS_LOCKED))
2473 mtx_lock(&ps->ps_mtx);
2474 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, i))
2475 tdsigwakeup(td, i, SIG_CATCH,
2476 (SIGISMEMBER(ps->ps_sigintr, i) ? EINTR :
2478 if (!(flags & SIGPROCMASK_PS_LOCKED))
2479 mtx_unlock(&ps->ps_mtx);
2484 tdsigcleanup(struct thread *td)
2490 PROC_LOCK_ASSERT(p, MA_OWNED);
2492 sigqueue_flush(&td->td_sigqueue);
2493 if (p->p_numthreads == 1)
2497 * Since we cannot handle signals, notify signal post code
2498 * about this by filling the sigmask.
2500 * Also, if needed, wake up thread(s) that do not block the
2501 * same signals as the exiting thread, since the thread might
2502 * have been selected for delivery and woken up.
2504 SIGFILLSET(unblocked);
2505 SIGSETNAND(unblocked, td->td_sigmask);
2506 SIGFILLSET(td->td_sigmask);
2507 reschedule_signals(p, unblocked, 0);
2512 * If the current process has received a signal (should be caught or cause
2513 * termination, should interrupt current syscall), return the signal number.
2514 * Stop signals with default action are processed immediately, then cleared;
2515 * they aren't returned. This is checked after each entry to the system for
2516 * a syscall or trap (though this can usually be done without calling issignal
2517 * by checking the pending signal masks in cursig.) The normal call
2520 * while (sig = cursig(curthread))
2524 issignal(struct thread *td, int stop_allowed)
2528 struct sigqueue *queue;
2529 sigset_t sigpending;
2530 int sig, prop, newsig;
2534 mtx_assert(&ps->ps_mtx, MA_OWNED);
2535 PROC_LOCK_ASSERT(p, MA_OWNED);
2537 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2539 sigpending = td->td_sigqueue.sq_signals;
2540 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2541 SIGSETNAND(sigpending, td->td_sigmask);
2543 if (p->p_flag & P_PPWAIT)
2544 SIG_STOPSIGMASK(sigpending);
2545 if (SIGISEMPTY(sigpending)) /* no signal to send */
2547 sig = sig_ffs(&sigpending);
2549 if (p->p_stops & S_SIG) {
2550 mtx_unlock(&ps->ps_mtx);
2551 stopevent(p, S_SIG, sig);
2552 mtx_lock(&ps->ps_mtx);
2556 * We should see pending but ignored signals
2557 * only if P_TRACED was on when they were posted.
2559 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2560 sigqueue_delete(&td->td_sigqueue, sig);
2561 sigqueue_delete(&p->p_sigqueue, sig);
2564 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
2566 * If traced, always stop.
2567 * Remove old signal from queue before the stop.
2568 * XXX shrug off debugger, it causes siginfo to
2571 queue = &td->td_sigqueue;
2572 td->td_dbgksi.ksi_signo = 0;
2573 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2574 queue = &p->p_sigqueue;
2575 sigqueue_get(queue, sig, &td->td_dbgksi);
2578 mtx_unlock(&ps->ps_mtx);
2579 newsig = ptracestop(td, sig);
2580 mtx_lock(&ps->ps_mtx);
2582 if (sig != newsig) {
2585 * If parent wants us to take the signal,
2586 * then it will leave it in p->p_xstat;
2587 * otherwise we just look for signals again.
2594 * Put the new signal into td_sigqueue. If the
2595 * signal is being masked, look for other signals.
2597 sigqueue_add(queue, sig, NULL);
2598 if (SIGISMEMBER(td->td_sigmask, sig))
2602 if (td->td_dbgksi.ksi_signo != 0) {
2603 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2604 if (sigqueue_add(&td->td_sigqueue, sig,
2605 &td->td_dbgksi) != 0)
2606 td->td_dbgksi.ksi_signo = 0;
2608 if (td->td_dbgksi.ksi_signo == 0)
2609 sigqueue_add(&td->td_sigqueue, sig,
2614 * If the traced bit got turned off, go back up
2615 * to the top to rescan signals. This ensures
2616 * that p_sig* and p_sigact are consistent.
2618 if ((p->p_flag & P_TRACED) == 0)
2622 prop = sigprop(sig);
2625 * Decide whether the signal should be returned.
2626 * Return the signal's number, or fall through
2627 * to clear it from the pending mask.
2629 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2631 case (intptr_t)SIG_DFL:
2633 * Don't take default actions on system processes.
2635 if (p->p_pid <= 1) {
2638 * Are you sure you want to ignore SIGSEGV
2641 printf("Process (pid %lu) got signal %d\n",
2642 (u_long)p->p_pid, sig);
2644 break; /* == ignore */
2647 * If there is a pending stop signal to process
2648 * with default action, stop here,
2649 * then clear the signal. However,
2650 * if process is member of an orphaned
2651 * process group, ignore tty stop signals.
2653 if (prop & SA_STOP) {
2654 if (p->p_flag & P_TRACED ||
2655 (p->p_pgrp->pg_jobc == 0 &&
2657 break; /* == ignore */
2659 /* Ignore, but do not drop the stop signal. */
2660 if (stop_allowed != SIG_STOP_ALLOWED)
2662 mtx_unlock(&ps->ps_mtx);
2663 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2664 &p->p_mtx.lock_object, "Catching SIGSTOP");
2665 p->p_flag |= P_STOPPED_SIG;
2668 sig_suspend_threads(td, p, 0);
2669 thread_suspend_switch(td);
2671 mtx_lock(&ps->ps_mtx);
2673 } else if (prop & SA_IGNORE) {
2675 * Except for SIGCONT, shouldn't get here.
2676 * Default action is to ignore; drop it.
2678 break; /* == ignore */
2683 case (intptr_t)SIG_IGN:
2685 * Masking above should prevent us ever trying
2686 * to take action on an ignored signal other
2687 * than SIGCONT, unless process is traced.
2689 if ((prop & SA_CONT) == 0 &&
2690 (p->p_flag & P_TRACED) == 0)
2691 printf("issignal\n");
2692 break; /* == ignore */
2696 * This signal has an action, let
2697 * postsig() process it.
2701 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2702 sigqueue_delete(&p->p_sigqueue, sig);
2708 thread_stopped(struct proc *p)
2712 PROC_LOCK_ASSERT(p, MA_OWNED);
2713 PROC_SLOCK_ASSERT(p, MA_OWNED);
2717 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2719 p->p_flag &= ~P_WAITED;
2720 PROC_LOCK(p->p_pptr);
2721 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2722 CLD_TRAPPED : CLD_STOPPED);
2723 PROC_UNLOCK(p->p_pptr);
2729 * Take the action for the specified signal
2730 * from the current set of pending signals.
2736 struct thread *td = curthread;
2737 register struct proc *p = td->td_proc;
2741 sigset_t returnmask, mask;
2743 KASSERT(sig != 0, ("postsig"));
2745 PROC_LOCK_ASSERT(p, MA_OWNED);
2747 mtx_assert(&ps->ps_mtx, MA_OWNED);
2748 ksiginfo_init(&ksi);
2749 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2750 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2752 ksi.ksi_signo = sig;
2753 if (ksi.ksi_code == SI_TIMER)
2754 itimer_accept(p, ksi.ksi_timerid, &ksi);
2755 action = ps->ps_sigact[_SIG_IDX(sig)];
2757 if (KTRPOINT(td, KTR_PSIG))
2758 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2759 &td->td_oldsigmask : &td->td_sigmask, 0);
2761 if (p->p_stops & S_SIG) {
2762 mtx_unlock(&ps->ps_mtx);
2763 stopevent(p, S_SIG, sig);
2764 mtx_lock(&ps->ps_mtx);
2767 if (action == SIG_DFL) {
2769 * Default action, where the default is to kill
2770 * the process. (Other cases were ignored above.)
2772 mtx_unlock(&ps->ps_mtx);
2777 * If we get here, the signal must be caught.
2779 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2780 ("postsig action"));
2782 * Set the new mask value and also defer further
2783 * occurrences of this signal.
2785 * Special case: user has done a sigsuspend. Here the
2786 * current mask is not of interest, but rather the
2787 * mask from before the sigsuspend is what we want
2788 * restored after the signal processing is completed.
2790 if (td->td_pflags & TDP_OLDMASK) {
2791 returnmask = td->td_oldsigmask;
2792 td->td_pflags &= ~TDP_OLDMASK;
2794 returnmask = td->td_sigmask;
2796 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2797 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2798 SIGADDSET(mask, sig);
2799 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2800 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2802 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2804 * See kern_sigaction() for origin of this code.
2806 SIGDELSET(ps->ps_sigcatch, sig);
2807 if (sig != SIGCONT &&
2808 sigprop(sig) & SA_IGNORE)
2809 SIGADDSET(ps->ps_sigignore, sig);
2810 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2812 td->td_ru.ru_nsignals++;
2813 if (p->p_sig == sig) {
2817 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2823 * Kill the current process for stated reason.
2831 PROC_LOCK_ASSERT(p, MA_OWNED);
2832 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)",
2833 p, p->p_pid, p->p_comm);
2834 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
2835 p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2836 p->p_flag |= P_WKILLED;
2837 psignal(p, SIGKILL);
2841 * Force the current process to exit with the specified signal, dumping core
2842 * if appropriate. We bypass the normal tests for masked and caught signals,
2843 * allowing unrecoverable failures to terminate the process without changing
2844 * signal state. Mark the accounting record with the signal termination.
2845 * If dumping core, save the signal number for the debugger. Calls exit and
2853 struct proc *p = td->td_proc;
2855 PROC_LOCK_ASSERT(p, MA_OWNED);
2856 p->p_acflag |= AXSIG;
2858 * We must be single-threading to generate a core dump. This
2859 * ensures that the registers in the core file are up-to-date.
2860 * Also, the ELF dump handler assumes that the thread list doesn't
2861 * change out from under it.
2863 * XXX If another thread attempts to single-thread before us
2864 * (e.g. via fork()), we won't get a dump at all.
2866 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2869 * Log signals which would cause core dumps
2870 * (Log as LOG_INFO to appease those who don't want
2872 * XXX : Todo, as well as euid, write out ruid too
2873 * Note that coredump() drops proc lock.
2875 if (coredump(td) == 0)
2877 if (kern_logsigexit)
2879 "pid %d (%s), uid %d: exited on signal %d%s\n",
2880 p->p_pid, p->p_comm,
2881 td->td_ucred ? td->td_ucred->cr_uid : -1,
2883 sig & WCOREFLAG ? " (core dumped)" : "");
2886 exit1(td, W_EXITCODE(0, sig));
2891 * Send queued SIGCHLD to parent when child process's state
2895 sigparent(struct proc *p, int reason, int status)
2897 PROC_LOCK_ASSERT(p, MA_OWNED);
2898 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2900 if (p->p_ksi != NULL) {
2901 p->p_ksi->ksi_signo = SIGCHLD;
2902 p->p_ksi->ksi_code = reason;
2903 p->p_ksi->ksi_status = status;
2904 p->p_ksi->ksi_pid = p->p_pid;
2905 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2906 if (KSI_ONQ(p->p_ksi))
2909 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2913 childproc_jobstate(struct proc *p, int reason, int status)
2917 PROC_LOCK_ASSERT(p, MA_OWNED);
2918 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2921 * Wake up parent sleeping in kern_wait(), also send
2922 * SIGCHLD to parent, but SIGCHLD does not guarantee
2923 * that parent will awake, because parent may masked
2926 p->p_pptr->p_flag |= P_STATCHILD;
2929 ps = p->p_pptr->p_sigacts;
2930 mtx_lock(&ps->ps_mtx);
2931 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2932 mtx_unlock(&ps->ps_mtx);
2933 sigparent(p, reason, status);
2935 mtx_unlock(&ps->ps_mtx);
2939 childproc_stopped(struct proc *p, int reason)
2941 childproc_jobstate(p, reason, p->p_xstat);
2945 childproc_continued(struct proc *p)
2947 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
2951 childproc_exited(struct proc *p)
2954 int status = p->p_xstat; /* convert to int */
2956 reason = CLD_EXITED;
2957 if (WCOREDUMP(status))
2958 reason = CLD_DUMPED;
2959 else if (WIFSIGNALED(status))
2960 reason = CLD_KILLED;
2962 * XXX avoid calling wakeup(p->p_pptr), the work is
2965 sigparent(p, reason, status);
2969 * We only have 1 character for the core count in the format
2970 * string, so the range will be 0-9
2972 #define MAX_NUM_CORES 10
2973 static int num_cores = 5;
2976 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
2981 new_val = num_cores;
2982 error = sysctl_handle_int(oidp, &new_val, 0, req);
2983 if (error != 0 || req->newptr == NULL)
2985 if (new_val > MAX_NUM_CORES)
2986 new_val = MAX_NUM_CORES;
2989 num_cores = new_val;
2992 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
2993 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
2995 #if defined(COMPRESS_USER_CORES)
2996 int compress_user_cores = 1;
2997 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
2998 &compress_user_cores, 0, "");
3000 int compress_user_cores_gzlevel = -1; /* default level */
3001 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
3002 &compress_user_cores_gzlevel, -1, "user core gz compression level");
3004 #define GZ_SUFFIX ".gz"
3005 #define GZ_SUFFIX_LEN 3
3008 static char corefilename[MAXPATHLEN] = {"%N.core"};
3009 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3010 sizeof(corefilename), "process corefile name format string");
3013 * expand_name(name, uid, pid, td, compress)
3014 * Expand the name described in corefilename, using name, uid, and pid.
3015 * corefilename is a printf-like string, with three format specifiers:
3016 * %N name of process ("name")
3017 * %P process id (pid)
3019 * For example, "%N.core" is the default; they can be disabled completely
3020 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3021 * This is controlled by the sysctl variable kern.corefile (see above).
3024 expand_name(const char *name, uid_t uid, pid_t pid, struct thread *td,
3035 format = corefilename;
3036 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
3040 (void)sbuf_new(&sb, temp, MAXPATHLEN, SBUF_FIXEDLEN);
3041 for (i = 0; format[i]; i++) {
3042 switch (format[i]) {
3043 case '%': /* Format character */
3045 switch (format[i]) {
3047 sbuf_putc(&sb, '%');
3049 case 'H': /* hostname */
3050 if (hostname == NULL) {
3051 hostname = malloc(MAXHOSTNAMELEN,
3053 if (hostname == NULL) {
3055 "pid %ld (%s), uid (%lu): "
3056 "unable to alloc memory "
3057 "for corefile hostname\n",
3063 getcredhostname(td->td_ucred, hostname,
3065 sbuf_printf(&sb, "%s", hostname);
3067 case 'I': /* autoincrementing index */
3068 sbuf_printf(&sb, "0");
3069 indexpos = sbuf_len(&sb) - 1;
3071 case 'N': /* process name */
3072 sbuf_printf(&sb, "%s", name);
3074 case 'P': /* process id */
3075 sbuf_printf(&sb, "%u", pid);
3077 case 'U': /* user id */
3078 sbuf_printf(&sb, "%u", uid);
3082 "Unknown format character %c in "
3083 "corename `%s'\n", format[i], format);
3087 sbuf_putc(&sb, format[i]);
3090 free(hostname, M_TEMP);
3091 #ifdef COMPRESS_USER_CORES
3093 sbuf_printf(&sb, GZ_SUFFIX);
3096 if (sbuf_error(&sb) != 0) {
3097 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3098 "long\n", (long)pid, name, (u_long)uid);
3108 * If the core format has a %I in it, then we need to check
3109 * for existing corefiles before returning a name.
3110 * To do this we iterate over 0..num_cores to find a
3111 * non-existing core file name to use.
3113 if (indexpos != -1) {
3114 struct nameidata nd;
3116 int flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3117 int cmode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
3120 for (n = 0; n < num_cores; n++) {
3121 temp[indexpos] = '0' + n;
3122 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE,
3124 error = vn_open(&nd, &flags, cmode, NULL);
3126 if (error == EEXIST) {
3130 "pid %d (%s), uid (%u): Path `%s' failed "
3131 "on initial open test, error = %d\n",
3132 pid, name, uid, temp, error);
3136 vfslocked = NDHASGIANT(&nd);
3137 NDFREE(&nd, NDF_ONLY_PNBUF);
3138 VOP_UNLOCK(nd.ni_vp, 0);
3139 error = vn_close(nd.ni_vp, FWRITE, td->td_ucred, td);
3140 VFS_UNLOCK_GIANT(vfslocked);
3143 "pid %d (%s), uid (%u): Path `%s' failed "
3144 "on close after initial open test, "
3146 pid, name, uid, temp, error);
3157 * Dump a process' core. The main routine does some
3158 * policy checking, and creates the name of the coredump;
3159 * then it passes on a vnode and a size limit to the process-specific
3160 * coredump routine if there is one; if there _is not_ one, it returns
3161 * ENOSYS; otherwise it returns the error from the process-specific routine.
3165 coredump(struct thread *td)
3167 struct proc *p = td->td_proc;
3168 register struct vnode *vp;
3169 register struct ucred *cred = td->td_ucred;
3171 struct nameidata nd;
3173 int error, error1, flags, locked;
3175 char *name; /* name of corefile */
3180 #ifdef COMPRESS_USER_CORES
3181 compress = compress_user_cores;
3185 PROC_LOCK_ASSERT(p, MA_OWNED);
3186 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3187 _STOPEVENT(p, S_CORE, 0);
3189 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid, td,
3194 audit_proc_coredump(td, NULL, EINVAL);
3198 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) {
3201 audit_proc_coredump(td, name, EFAULT);
3208 * Note that the bulk of limit checking is done after
3209 * the corefile is created. The exception is if the limit
3210 * for corefiles is 0, in which case we don't bother
3211 * creating the corefile at all. This layout means that
3212 * a corefile is truncated instead of not being created,
3213 * if it is larger than the limit.
3215 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3219 audit_proc_coredump(td, name, EFBIG);
3226 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, name, td);
3227 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3228 error = vn_open_cred(&nd, &flags, S_IRUSR | S_IWUSR, VN_OPEN_NOAUDIT,
3232 audit_proc_coredump(td, name, error);
3237 vfslocked = NDHASGIANT(&nd);
3238 NDFREE(&nd, NDF_ONLY_PNBUF);
3241 /* Don't dump to non-regular files or files with links. */
3242 if (vp->v_type != VREG ||
3243 VOP_GETATTR(vp, &vattr, cred) || vattr.va_nlink != 1) {
3250 lf.l_whence = SEEK_SET;
3253 lf.l_type = F_WRLCK;
3254 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3256 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3257 lf.l_type = F_UNLCK;
3259 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3260 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3262 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3264 VFS_UNLOCK_GIANT(vfslocked);
3270 if (set_core_nodump_flag)
3271 vattr.va_flags = UF_NODUMP;
3272 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3273 VOP_SETATTR(vp, &vattr, cred);
3275 vn_finished_write(mp);
3277 p->p_acflag |= ACORE;
3280 error = p->p_sysent->sv_coredump ?
3281 p->p_sysent->sv_coredump(td, vp, limit, compress ? IMGACT_CORE_COMPRESS : 0) :
3285 lf.l_type = F_UNLCK;
3286 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3289 error1 = vn_close(vp, FWRITE, cred, td);
3294 audit_proc_coredump(td, name, error);
3297 VFS_UNLOCK_GIANT(vfslocked);
3302 * Nonexistent system call-- signal process (may want to handle it). Flag
3303 * error in case process won't see signal immediately (blocked or ignored).
3305 #ifndef _SYS_SYSPROTO_H_
3314 struct nosys_args *args;
3316 struct proc *p = td->td_proc;
3325 * Send a SIGIO or SIGURG signal to a process or process group using stored
3326 * credentials rather than those of the current process.
3329 pgsigio(sigiop, sig, checkctty)
3330 struct sigio **sigiop;
3334 struct sigio *sigio;
3336 ksiginfo_init(&ksi);
3337 ksi.ksi_signo = sig;
3338 ksi.ksi_code = SI_KERNEL;
3342 if (sigio == NULL) {
3346 if (sigio->sio_pgid > 0) {
3347 PROC_LOCK(sigio->sio_proc);
3348 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3349 psignal(sigio->sio_proc, sig);
3350 PROC_UNLOCK(sigio->sio_proc);
3351 } else if (sigio->sio_pgid < 0) {
3354 PGRP_LOCK(sigio->sio_pgrp);
3355 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3357 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3358 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3362 PGRP_UNLOCK(sigio->sio_pgrp);
3368 filt_sigattach(struct knote *kn)
3370 struct proc *p = curproc;
3372 kn->kn_ptr.p_proc = p;
3373 kn->kn_flags |= EV_CLEAR; /* automatically set */
3375 knlist_add(&p->p_klist, kn, 0);
3381 filt_sigdetach(struct knote *kn)
3383 struct proc *p = kn->kn_ptr.p_proc;
3385 knlist_remove(&p->p_klist, kn, 0);
3389 * signal knotes are shared with proc knotes, so we apply a mask to
3390 * the hint in order to differentiate them from process hints. This
3391 * could be avoided by using a signal-specific knote list, but probably
3392 * isn't worth the trouble.
3395 filt_signal(struct knote *kn, long hint)
3398 if (hint & NOTE_SIGNAL) {
3399 hint &= ~NOTE_SIGNAL;
3401 if (kn->kn_id == hint)
3404 return (kn->kn_data != 0);
3412 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3414 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3419 sigacts_free(struct sigacts *ps)
3422 mtx_lock(&ps->ps_mtx);
3424 if (ps->ps_refcnt == 0) {
3425 mtx_destroy(&ps->ps_mtx);
3426 free(ps, M_SUBPROC);
3428 mtx_unlock(&ps->ps_mtx);
3432 sigacts_hold(struct sigacts *ps)
3434 mtx_lock(&ps->ps_mtx);
3436 mtx_unlock(&ps->ps_mtx);
3441 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3444 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3445 mtx_lock(&src->ps_mtx);
3446 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3447 mtx_unlock(&src->ps_mtx);
3451 sigacts_shared(struct sigacts *ps)
3455 mtx_lock(&ps->ps_mtx);
3456 shared = ps->ps_refcnt > 1;
3457 mtx_unlock(&ps->ps_mtx);