2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
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25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
42 #include "opt_ktrace.h"
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
51 #include <sys/capsicum.h>
52 #include <sys/condvar.h>
53 #include <sys/event.h>
54 #include <sys/fcntl.h>
55 #include <sys/imgact.h>
56 #include <sys/kernel.h>
58 #include <sys/ktrace.h>
60 #include <sys/malloc.h>
61 #include <sys/mutex.h>
62 #include <sys/refcount.h>
63 #include <sys/namei.h>
65 #include <sys/procdesc.h>
66 #include <sys/posix4.h>
67 #include <sys/pioctl.h>
68 #include <sys/racct.h>
69 #include <sys/resourcevar.h>
72 #include <sys/sleepqueue.h>
76 #include <sys/syscallsubr.h>
77 #include <sys/sysctl.h>
78 #include <sys/sysent.h>
79 #include <sys/syslog.h>
80 #include <sys/sysproto.h>
81 #include <sys/timers.h>
82 #include <sys/unistd.h>
85 #include <vm/vm_extern.h>
90 #include <machine/cpu.h>
92 #include <security/audit/audit.h>
94 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE3(proc, kernel, , signal__send, "struct thread *",
98 "struct proc *", "int");
99 SDT_PROBE_DEFINE2(proc, kernel, , signal__clear, "int",
101 SDT_PROBE_DEFINE3(proc, kernel, , signal__discard,
102 "struct thread *", "struct proc *", "int");
104 static int coredump(struct thread *);
105 static int killpg1(struct thread *td, int sig, int pgid, int all,
107 static int issignal(struct thread *td);
108 static int sigprop(int sig);
109 static void tdsigwakeup(struct thread *, int, sig_t, int);
110 static void sig_suspend_threads(struct thread *, struct proc *, int);
111 static int filt_sigattach(struct knote *kn);
112 static void filt_sigdetach(struct knote *kn);
113 static int filt_signal(struct knote *kn, long hint);
114 static struct thread *sigtd(struct proc *p, int sig, int prop);
115 static void sigqueue_start(void);
117 static uma_zone_t ksiginfo_zone = NULL;
118 struct filterops sig_filtops = {
120 .f_attach = filt_sigattach,
121 .f_detach = filt_sigdetach,
122 .f_event = filt_signal,
125 static int kern_logsigexit = 1;
126 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
128 "Log processes quitting on abnormal signals to syslog(3)");
130 static int kern_forcesigexit = 1;
131 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
132 &kern_forcesigexit, 0, "Force trap signal to be handled");
134 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
135 "POSIX real time signal");
137 static int max_pending_per_proc = 128;
138 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
139 &max_pending_per_proc, 0, "Max pending signals per proc");
141 static int preallocate_siginfo = 1024;
142 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
143 &preallocate_siginfo, 0, "Preallocated signal memory size");
145 static int signal_overflow = 0;
146 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
147 &signal_overflow, 0, "Number of signals overflew");
149 static int signal_alloc_fail = 0;
150 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
151 &signal_alloc_fail, 0, "signals failed to be allocated");
153 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
156 * Policy -- Can ucred cr1 send SIGIO to process cr2?
157 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
158 * in the right situations.
160 #define CANSIGIO(cr1, cr2) \
161 ((cr1)->cr_uid == 0 || \
162 (cr1)->cr_ruid == (cr2)->cr_ruid || \
163 (cr1)->cr_uid == (cr2)->cr_ruid || \
164 (cr1)->cr_ruid == (cr2)->cr_uid || \
165 (cr1)->cr_uid == (cr2)->cr_uid)
167 static int sugid_coredump;
168 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
169 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
171 static int capmode_coredump;
172 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
173 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
175 static int do_coredump = 1;
176 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
177 &do_coredump, 0, "Enable/Disable coredumps");
179 static int set_core_nodump_flag = 0;
180 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
181 0, "Enable setting the NODUMP flag on coredump files");
183 static int coredump_devctl = 0;
184 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
185 0, "Generate a devctl notification when processes coredump");
188 * Signal properties and actions.
189 * The array below categorizes the signals and their default actions
190 * according to the following properties:
192 #define SA_KILL 0x01 /* terminates process by default */
193 #define SA_CORE 0x02 /* ditto and coredumps */
194 #define SA_STOP 0x04 /* suspend process */
195 #define SA_TTYSTOP 0x08 /* ditto, from tty */
196 #define SA_IGNORE 0x10 /* ignore by default */
197 #define SA_CONT 0x20 /* continue if suspended */
198 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
200 static int sigproptbl[NSIG] = {
201 SA_KILL, /* SIGHUP */
202 SA_KILL, /* SIGINT */
203 SA_KILL|SA_CORE, /* SIGQUIT */
204 SA_KILL|SA_CORE, /* SIGILL */
205 SA_KILL|SA_CORE, /* SIGTRAP */
206 SA_KILL|SA_CORE, /* SIGABRT */
207 SA_KILL|SA_CORE, /* SIGEMT */
208 SA_KILL|SA_CORE, /* SIGFPE */
209 SA_KILL, /* SIGKILL */
210 SA_KILL|SA_CORE, /* SIGBUS */
211 SA_KILL|SA_CORE, /* SIGSEGV */
212 SA_KILL|SA_CORE, /* SIGSYS */
213 SA_KILL, /* SIGPIPE */
214 SA_KILL, /* SIGALRM */
215 SA_KILL, /* SIGTERM */
216 SA_IGNORE, /* SIGURG */
217 SA_STOP, /* SIGSTOP */
218 SA_STOP|SA_TTYSTOP, /* SIGTSTP */
219 SA_IGNORE|SA_CONT, /* SIGCONT */
220 SA_IGNORE, /* SIGCHLD */
221 SA_STOP|SA_TTYSTOP, /* SIGTTIN */
222 SA_STOP|SA_TTYSTOP, /* SIGTTOU */
223 SA_IGNORE, /* SIGIO */
224 SA_KILL, /* SIGXCPU */
225 SA_KILL, /* SIGXFSZ */
226 SA_KILL, /* SIGVTALRM */
227 SA_KILL, /* SIGPROF */
228 SA_IGNORE, /* SIGWINCH */
229 SA_IGNORE, /* SIGINFO */
230 SA_KILL, /* SIGUSR1 */
231 SA_KILL, /* SIGUSR2 */
234 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
239 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
240 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
241 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
242 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
243 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
244 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
248 ksiginfo_alloc(int wait)
255 if (ksiginfo_zone != NULL)
256 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
261 ksiginfo_free(ksiginfo_t *ksi)
263 uma_zfree(ksiginfo_zone, ksi);
267 ksiginfo_tryfree(ksiginfo_t *ksi)
269 if (!(ksi->ksi_flags & KSI_EXT)) {
270 uma_zfree(ksiginfo_zone, ksi);
277 sigqueue_init(sigqueue_t *list, struct proc *p)
279 SIGEMPTYSET(list->sq_signals);
280 SIGEMPTYSET(list->sq_kill);
281 TAILQ_INIT(&list->sq_list);
283 list->sq_flags = SQ_INIT;
287 * Get a signal's ksiginfo.
289 * 0 - signal not found
290 * others - signal number
293 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
295 struct proc *p = sq->sq_proc;
296 struct ksiginfo *ksi, *next;
299 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
301 if (!SIGISMEMBER(sq->sq_signals, signo))
304 if (SIGISMEMBER(sq->sq_kill, signo)) {
306 SIGDELSET(sq->sq_kill, signo);
309 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
310 if (ksi->ksi_signo == signo) {
312 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
313 ksi->ksi_sigq = NULL;
314 ksiginfo_copy(ksi, si);
315 if (ksiginfo_tryfree(ksi) && p != NULL)
324 SIGDELSET(sq->sq_signals, signo);
325 si->ksi_signo = signo;
330 sigqueue_take(ksiginfo_t *ksi)
336 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
340 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
341 ksi->ksi_sigq = NULL;
342 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
345 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
346 kp = TAILQ_NEXT(kp, ksi_link)) {
347 if (kp->ksi_signo == ksi->ksi_signo)
350 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
351 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
355 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
357 struct proc *p = sq->sq_proc;
358 struct ksiginfo *ksi;
361 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
363 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
364 SIGADDSET(sq->sq_kill, signo);
368 /* directly insert the ksi, don't copy it */
369 if (si->ksi_flags & KSI_INS) {
370 if (si->ksi_flags & KSI_HEAD)
371 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
373 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
378 if (__predict_false(ksiginfo_zone == NULL)) {
379 SIGADDSET(sq->sq_kill, signo);
383 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
386 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
392 ksiginfo_copy(si, ksi);
393 ksi->ksi_signo = signo;
394 if (si->ksi_flags & KSI_HEAD)
395 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
397 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
401 if ((si->ksi_flags & KSI_TRAP) != 0 ||
402 (si->ksi_flags & KSI_SIGQ) == 0) {
404 SIGADDSET(sq->sq_kill, signo);
413 SIGADDSET(sq->sq_signals, signo);
418 sigqueue_flush(sigqueue_t *sq)
420 struct proc *p = sq->sq_proc;
423 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
426 PROC_LOCK_ASSERT(p, MA_OWNED);
428 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
429 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
430 ksi->ksi_sigq = NULL;
431 if (ksiginfo_tryfree(ksi) && p != NULL)
435 SIGEMPTYSET(sq->sq_signals);
436 SIGEMPTYSET(sq->sq_kill);
440 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
443 struct proc *p1, *p2;
444 ksiginfo_t *ksi, *next;
446 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
447 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
450 /* Move siginfo to target list */
451 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
452 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
453 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
456 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
463 /* Move pending bits to target list */
465 SIGSETAND(tmp, *set);
466 SIGSETOR(dst->sq_kill, tmp);
467 SIGSETNAND(src->sq_kill, tmp);
469 tmp = src->sq_signals;
470 SIGSETAND(tmp, *set);
471 SIGSETOR(dst->sq_signals, tmp);
472 SIGSETNAND(src->sq_signals, tmp);
477 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
482 SIGADDSET(set, signo);
483 sigqueue_move_set(src, dst, &set);
488 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
490 struct proc *p = sq->sq_proc;
491 ksiginfo_t *ksi, *next;
493 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
495 /* Remove siginfo queue */
496 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
497 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
498 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
499 ksi->ksi_sigq = NULL;
500 if (ksiginfo_tryfree(ksi) && p != NULL)
504 SIGSETNAND(sq->sq_kill, *set);
505 SIGSETNAND(sq->sq_signals, *set);
509 sigqueue_delete(sigqueue_t *sq, int signo)
514 SIGADDSET(set, signo);
515 sigqueue_delete_set(sq, &set);
518 /* Remove a set of signals for a process */
520 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
525 PROC_LOCK_ASSERT(p, MA_OWNED);
527 sigqueue_init(&worklist, NULL);
528 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
530 FOREACH_THREAD_IN_PROC(p, td0)
531 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
533 sigqueue_flush(&worklist);
537 sigqueue_delete_proc(struct proc *p, int signo)
542 SIGADDSET(set, signo);
543 sigqueue_delete_set_proc(p, &set);
547 sigqueue_delete_stopmask_proc(struct proc *p)
552 SIGADDSET(set, SIGSTOP);
553 SIGADDSET(set, SIGTSTP);
554 SIGADDSET(set, SIGTTIN);
555 SIGADDSET(set, SIGTTOU);
556 sigqueue_delete_set_proc(p, &set);
560 * Determine signal that should be delivered to thread td, the current
561 * thread, 0 if none. If there is a pending stop signal with default
562 * action, the process stops in issignal().
565 cursig(struct thread *td)
567 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
568 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
569 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
570 return (SIGPENDING(td) ? issignal(td) : 0);
574 * Arrange for ast() to handle unmasked pending signals on return to user
575 * mode. This must be called whenever a signal is added to td_sigqueue or
576 * unmasked in td_sigmask.
579 signotify(struct thread *td)
585 PROC_LOCK_ASSERT(p, MA_OWNED);
587 if (SIGPENDING(td)) {
589 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
595 sigonstack(size_t sp)
597 struct thread *td = curthread;
599 return ((td->td_pflags & TDP_ALTSTACK) ?
600 #if defined(COMPAT_43)
601 ((td->td_sigstk.ss_size == 0) ?
602 (td->td_sigstk.ss_flags & SS_ONSTACK) :
603 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
605 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
614 if (sig > 0 && sig < NSIG)
615 return (sigproptbl[_SIG_IDX(sig)]);
620 sig_ffs(sigset_t *set)
624 for (i = 0; i < _SIG_WORDS; i++)
626 return (ffs(set->__bits[i]) + (i * 32));
631 sigact_flag_test(struct sigaction *act, int flag)
635 * SA_SIGINFO is reset when signal disposition is set to
636 * ignore or default. Other flags are kept according to user
639 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
640 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
641 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
651 kern_sigaction(td, sig, act, oact, flags)
654 struct sigaction *act, *oact;
658 struct proc *p = td->td_proc;
660 if (!_SIG_VALID(sig))
662 if (act != NULL && act->sa_handler != SIG_DFL &&
663 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
664 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
665 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
670 mtx_lock(&ps->ps_mtx);
672 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
674 if (SIGISMEMBER(ps->ps_sigonstack, sig))
675 oact->sa_flags |= SA_ONSTACK;
676 if (!SIGISMEMBER(ps->ps_sigintr, sig))
677 oact->sa_flags |= SA_RESTART;
678 if (SIGISMEMBER(ps->ps_sigreset, sig))
679 oact->sa_flags |= SA_RESETHAND;
680 if (SIGISMEMBER(ps->ps_signodefer, sig))
681 oact->sa_flags |= SA_NODEFER;
682 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
683 oact->sa_flags |= SA_SIGINFO;
685 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
687 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
688 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
689 oact->sa_flags |= SA_NOCLDSTOP;
690 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
691 oact->sa_flags |= SA_NOCLDWAIT;
694 if ((sig == SIGKILL || sig == SIGSTOP) &&
695 act->sa_handler != SIG_DFL) {
696 mtx_unlock(&ps->ps_mtx);
702 * Change setting atomically.
705 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
706 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
707 if (sigact_flag_test(act, SA_SIGINFO)) {
708 ps->ps_sigact[_SIG_IDX(sig)] =
709 (__sighandler_t *)act->sa_sigaction;
710 SIGADDSET(ps->ps_siginfo, sig);
712 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
713 SIGDELSET(ps->ps_siginfo, sig);
715 if (!sigact_flag_test(act, SA_RESTART))
716 SIGADDSET(ps->ps_sigintr, sig);
718 SIGDELSET(ps->ps_sigintr, sig);
719 if (sigact_flag_test(act, SA_ONSTACK))
720 SIGADDSET(ps->ps_sigonstack, sig);
722 SIGDELSET(ps->ps_sigonstack, sig);
723 if (sigact_flag_test(act, SA_RESETHAND))
724 SIGADDSET(ps->ps_sigreset, sig);
726 SIGDELSET(ps->ps_sigreset, sig);
727 if (sigact_flag_test(act, SA_NODEFER))
728 SIGADDSET(ps->ps_signodefer, sig);
730 SIGDELSET(ps->ps_signodefer, sig);
731 if (sig == SIGCHLD) {
732 if (act->sa_flags & SA_NOCLDSTOP)
733 ps->ps_flag |= PS_NOCLDSTOP;
735 ps->ps_flag &= ~PS_NOCLDSTOP;
736 if (act->sa_flags & SA_NOCLDWAIT) {
738 * Paranoia: since SA_NOCLDWAIT is implemented
739 * by reparenting the dying child to PID 1 (and
740 * trust it to reap the zombie), PID 1 itself
741 * is forbidden to set SA_NOCLDWAIT.
744 ps->ps_flag &= ~PS_NOCLDWAIT;
746 ps->ps_flag |= PS_NOCLDWAIT;
748 ps->ps_flag &= ~PS_NOCLDWAIT;
749 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
750 ps->ps_flag |= PS_CLDSIGIGN;
752 ps->ps_flag &= ~PS_CLDSIGIGN;
755 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
756 * and for signals set to SIG_DFL where the default is to
757 * ignore. However, don't put SIGCONT in ps_sigignore, as we
758 * have to restart the process.
760 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
761 (sigprop(sig) & SA_IGNORE &&
762 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
763 /* never to be seen again */
764 sigqueue_delete_proc(p, sig);
766 /* easier in psignal */
767 SIGADDSET(ps->ps_sigignore, sig);
768 SIGDELSET(ps->ps_sigcatch, sig);
770 SIGDELSET(ps->ps_sigignore, sig);
771 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
772 SIGDELSET(ps->ps_sigcatch, sig);
774 SIGADDSET(ps->ps_sigcatch, sig);
776 #ifdef COMPAT_FREEBSD4
777 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
778 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
779 (flags & KSA_FREEBSD4) == 0)
780 SIGDELSET(ps->ps_freebsd4, sig);
782 SIGADDSET(ps->ps_freebsd4, sig);
785 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
786 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
787 (flags & KSA_OSIGSET) == 0)
788 SIGDELSET(ps->ps_osigset, sig);
790 SIGADDSET(ps->ps_osigset, sig);
793 mtx_unlock(&ps->ps_mtx);
798 #ifndef _SYS_SYSPROTO_H_
799 struct sigaction_args {
801 struct sigaction *act;
802 struct sigaction *oact;
806 sys_sigaction(td, uap)
808 register struct sigaction_args *uap;
810 struct sigaction act, oact;
811 register struct sigaction *actp, *oactp;
814 actp = (uap->act != NULL) ? &act : NULL;
815 oactp = (uap->oact != NULL) ? &oact : NULL;
817 error = copyin(uap->act, actp, sizeof(act));
821 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
823 error = copyout(oactp, uap->oact, sizeof(oact));
827 #ifdef COMPAT_FREEBSD4
828 #ifndef _SYS_SYSPROTO_H_
829 struct freebsd4_sigaction_args {
831 struct sigaction *act;
832 struct sigaction *oact;
836 freebsd4_sigaction(td, uap)
838 register struct freebsd4_sigaction_args *uap;
840 struct sigaction act, oact;
841 register struct sigaction *actp, *oactp;
845 actp = (uap->act != NULL) ? &act : NULL;
846 oactp = (uap->oact != NULL) ? &oact : NULL;
848 error = copyin(uap->act, actp, sizeof(act));
852 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
854 error = copyout(oactp, uap->oact, sizeof(oact));
857 #endif /* COMAPT_FREEBSD4 */
859 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
860 #ifndef _SYS_SYSPROTO_H_
861 struct osigaction_args {
863 struct osigaction *nsa;
864 struct osigaction *osa;
870 register struct osigaction_args *uap;
872 struct osigaction sa;
873 struct sigaction nsa, osa;
874 register struct sigaction *nsap, *osap;
877 if (uap->signum <= 0 || uap->signum >= ONSIG)
880 nsap = (uap->nsa != NULL) ? &nsa : NULL;
881 osap = (uap->osa != NULL) ? &osa : NULL;
884 error = copyin(uap->nsa, &sa, sizeof(sa));
887 nsap->sa_handler = sa.sa_handler;
888 nsap->sa_flags = sa.sa_flags;
889 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
891 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
892 if (osap && !error) {
893 sa.sa_handler = osap->sa_handler;
894 sa.sa_flags = osap->sa_flags;
895 SIG2OSIG(osap->sa_mask, sa.sa_mask);
896 error = copyout(&sa, uap->osa, sizeof(sa));
901 #if !defined(__i386__)
902 /* Avoid replicating the same stub everywhere */
906 struct osigreturn_args *uap;
909 return (nosys(td, (struct nosys_args *)uap));
912 #endif /* COMPAT_43 */
915 * Initialize signal state for process 0;
916 * set to ignore signals that are ignored by default.
927 mtx_lock(&ps->ps_mtx);
928 for (i = 1; i <= NSIG; i++) {
929 if (sigprop(i) & SA_IGNORE && i != SIGCONT) {
930 SIGADDSET(ps->ps_sigignore, i);
933 mtx_unlock(&ps->ps_mtx);
938 * Reset specified signal to the default disposition.
941 sigdflt(struct sigacts *ps, int sig)
944 mtx_assert(&ps->ps_mtx, MA_OWNED);
945 SIGDELSET(ps->ps_sigcatch, sig);
946 if ((sigprop(sig) & SA_IGNORE) != 0 && sig != SIGCONT)
947 SIGADDSET(ps->ps_sigignore, sig);
948 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
949 SIGDELSET(ps->ps_siginfo, sig);
953 * Reset signals for an exec of the specified process.
956 execsigs(struct proc *p)
963 * Reset caught signals. Held signals remain held
964 * through td_sigmask (unless they were caught,
965 * and are now ignored by default).
967 PROC_LOCK_ASSERT(p, MA_OWNED);
968 td = FIRST_THREAD_IN_PROC(p);
970 mtx_lock(&ps->ps_mtx);
971 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
972 sig = sig_ffs(&ps->ps_sigcatch);
974 if ((sigprop(sig) & SA_IGNORE) != 0)
975 sigqueue_delete_proc(p, sig);
978 * Reset stack state to the user stack.
979 * Clear set of signals caught on the signal stack.
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_PROBE(proc, kernel, , signal__clear, sig, ksi, 0, 0, 0);
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;
1766 cap_rights_t rights;
1769 AUDIT_ARG_SIGNUM(uap->signum);
1770 AUDIT_ARG_FD(uap->fd);
1771 if ((u_int)uap->signum > _SIG_MAXSIG)
1774 error = procdesc_find(td, uap->fd,
1775 cap_rights_init(&rights, CAP_PDKILL), &p);
1778 AUDIT_ARG_PROCESS(p);
1779 error = p_cansignal(td, p, uap->signum);
1780 if (error == 0 && uap->signum)
1781 kern_psignal(p, uap->signum);
1786 #if defined(COMPAT_43)
1787 #ifndef _SYS_SYSPROTO_H_
1788 struct okillpg_args {
1795 okillpg(struct thread *td, struct okillpg_args *uap)
1799 AUDIT_ARG_SIGNUM(uap->signum);
1800 AUDIT_ARG_PID(uap->pgid);
1801 if ((u_int)uap->signum > _SIG_MAXSIG)
1804 ksiginfo_init(&ksi);
1805 ksi.ksi_signo = uap->signum;
1806 ksi.ksi_code = SI_USER;
1807 ksi.ksi_pid = td->td_proc->p_pid;
1808 ksi.ksi_uid = td->td_ucred->cr_ruid;
1809 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1811 #endif /* COMPAT_43 */
1813 #ifndef _SYS_SYSPROTO_H_
1814 struct sigqueue_args {
1817 /* union sigval */ void *value;
1821 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1827 if ((u_int)uap->signum > _SIG_MAXSIG)
1831 * Specification says sigqueue can only send signal to
1837 if ((p = pfind(uap->pid)) == NULL) {
1838 if ((p = zpfind(uap->pid)) == NULL)
1841 error = p_cansignal(td, p, uap->signum);
1842 if (error == 0 && uap->signum != 0) {
1843 ksiginfo_init(&ksi);
1844 ksi.ksi_flags = KSI_SIGQ;
1845 ksi.ksi_signo = uap->signum;
1846 ksi.ksi_code = SI_QUEUE;
1847 ksi.ksi_pid = td->td_proc->p_pid;
1848 ksi.ksi_uid = td->td_ucred->cr_ruid;
1849 ksi.ksi_value.sival_ptr = uap->value;
1850 error = pksignal(p, ksi.ksi_signo, &ksi);
1857 * Send a signal to a process group.
1860 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1865 sx_slock(&proctree_lock);
1866 pgrp = pgfind(pgid);
1867 sx_sunlock(&proctree_lock);
1869 pgsignal(pgrp, sig, 0, ksi);
1876 * Send a signal to a process group. If checktty is 1,
1877 * limit to members which have a controlling terminal.
1880 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1885 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1886 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1888 if (p->p_state == PRS_NORMAL &&
1889 (checkctty == 0 || p->p_flag & P_CONTROLT))
1890 pksignal(p, sig, ksi);
1898 * Recalculate the signal mask and reset the signal disposition after
1899 * usermode frame for delivery is formed. Should be called after
1900 * mach-specific routine, because sysent->sv_sendsig() needs correct
1901 * ps_siginfo and signal mask.
1904 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1908 mtx_assert(&ps->ps_mtx, MA_OWNED);
1909 td->td_ru.ru_nsignals++;
1910 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1911 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1912 SIGADDSET(mask, sig);
1913 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1914 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1915 if (SIGISMEMBER(ps->ps_sigreset, sig))
1921 * Send a signal caused by a trap to the current thread. If it will be
1922 * caught immediately, deliver it with correct code. Otherwise, post it
1926 trapsignal(struct thread *td, ksiginfo_t *ksi)
1934 sig = ksi->ksi_signo;
1935 code = ksi->ksi_code;
1936 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1940 mtx_lock(&ps->ps_mtx);
1941 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1942 !SIGISMEMBER(td->td_sigmask, sig)) {
1944 if (KTRPOINT(curthread, KTR_PSIG))
1945 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1946 &td->td_sigmask, code);
1948 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1949 ksi, &td->td_sigmask);
1950 postsig_done(sig, td, ps);
1951 mtx_unlock(&ps->ps_mtx);
1954 * Avoid a possible infinite loop if the thread
1955 * masking the signal or process is ignoring the
1958 if (kern_forcesigexit &&
1959 (SIGISMEMBER(td->td_sigmask, sig) ||
1960 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1961 SIGDELSET(td->td_sigmask, sig);
1962 SIGDELSET(ps->ps_sigcatch, sig);
1963 SIGDELSET(ps->ps_sigignore, sig);
1964 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1966 mtx_unlock(&ps->ps_mtx);
1967 p->p_code = code; /* XXX for core dump/debugger */
1968 p->p_sig = sig; /* XXX to verify code */
1969 tdsendsignal(p, td, sig, ksi);
1974 static struct thread *
1975 sigtd(struct proc *p, int sig, int prop)
1977 struct thread *td, *signal_td;
1979 PROC_LOCK_ASSERT(p, MA_OWNED);
1982 * Check if current thread can handle the signal without
1983 * switching context to another thread.
1985 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1988 FOREACH_THREAD_IN_PROC(p, td) {
1989 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1994 if (signal_td == NULL)
1995 signal_td = FIRST_THREAD_IN_PROC(p);
2000 * Send the signal to the process. If the signal has an action, the action
2001 * is usually performed by the target process rather than the caller; we add
2002 * the signal to the set of pending signals for the process.
2005 * o When a stop signal is sent to a sleeping process that takes the
2006 * default action, the process is stopped without awakening it.
2007 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2008 * regardless of the signal action (eg, blocked or ignored).
2010 * Other ignored signals are discarded immediately.
2012 * NB: This function may be entered from the debugger via the "kill" DDB
2013 * command. There is little that can be done to mitigate the possibly messy
2014 * side effects of this unwise possibility.
2017 kern_psignal(struct proc *p, int sig)
2021 ksiginfo_init(&ksi);
2022 ksi.ksi_signo = sig;
2023 ksi.ksi_code = SI_KERNEL;
2024 (void) tdsendsignal(p, NULL, sig, &ksi);
2028 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2031 return (tdsendsignal(p, NULL, sig, ksi));
2034 /* Utility function for finding a thread to send signal event to. */
2036 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2040 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2041 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2053 tdsignal(struct thread *td, int sig)
2057 ksiginfo_init(&ksi);
2058 ksi.ksi_signo = sig;
2059 ksi.ksi_code = SI_KERNEL;
2060 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2064 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2067 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2071 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2074 sigqueue_t *sigqueue;
2081 MPASS(td == NULL || p == td->td_proc);
2082 PROC_LOCK_ASSERT(p, MA_OWNED);
2084 if (!_SIG_VALID(sig))
2085 panic("%s(): invalid signal %d", __func__, sig);
2087 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2090 * IEEE Std 1003.1-2001: return success when killing a zombie.
2092 if (p->p_state == PRS_ZOMBIE) {
2093 if (ksi && (ksi->ksi_flags & KSI_INS))
2094 ksiginfo_tryfree(ksi);
2099 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2100 prop = sigprop(sig);
2103 td = sigtd(p, sig, prop);
2104 sigqueue = &p->p_sigqueue;
2106 sigqueue = &td->td_sigqueue;
2108 SDT_PROBE(proc, kernel, , signal__send, td, p, sig, 0, 0 );
2111 * If the signal is being ignored,
2112 * then we forget about it immediately.
2113 * (Note: we don't set SIGCONT in ps_sigignore,
2114 * and if it is set to SIG_IGN,
2115 * action will be SIG_DFL here.)
2117 mtx_lock(&ps->ps_mtx);
2118 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2119 SDT_PROBE(proc, kernel, , signal__discard, td, p, sig, 0, 0 );
2121 mtx_unlock(&ps->ps_mtx);
2122 if (ksi && (ksi->ksi_flags & KSI_INS))
2123 ksiginfo_tryfree(ksi);
2126 if (SIGISMEMBER(td->td_sigmask, sig))
2128 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2132 if (SIGISMEMBER(ps->ps_sigintr, sig))
2136 mtx_unlock(&ps->ps_mtx);
2139 sigqueue_delete_stopmask_proc(p);
2140 else if (prop & SA_STOP) {
2142 * If sending a tty stop signal to a member of an orphaned
2143 * process group, discard the signal here if the action
2144 * is default; don't stop the process below if sleeping,
2145 * and don't clear any pending SIGCONT.
2147 if ((prop & SA_TTYSTOP) &&
2148 (p->p_pgrp->pg_jobc == 0) &&
2149 (action == SIG_DFL)) {
2150 if (ksi && (ksi->ksi_flags & KSI_INS))
2151 ksiginfo_tryfree(ksi);
2154 sigqueue_delete_proc(p, SIGCONT);
2155 if (p->p_flag & P_CONTINUED) {
2156 p->p_flag &= ~P_CONTINUED;
2157 PROC_LOCK(p->p_pptr);
2158 sigqueue_take(p->p_ksi);
2159 PROC_UNLOCK(p->p_pptr);
2163 ret = sigqueue_add(sigqueue, sig, ksi);
2168 * Defer further processing for signals which are held,
2169 * except that stopped processes must be continued by SIGCONT.
2171 if (action == SIG_HOLD &&
2172 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2175 * SIGKILL: Remove procfs STOPEVENTs.
2177 if (sig == SIGKILL) {
2178 /* from procfs_ioctl.c: PIOCBIC */
2180 /* from procfs_ioctl.c: PIOCCONT */
2185 * Some signals have a process-wide effect and a per-thread
2186 * component. Most processing occurs when the process next
2187 * tries to cross the user boundary, however there are some
2188 * times when processing needs to be done immediately, such as
2189 * waking up threads so that they can cross the user boundary.
2190 * We try to do the per-process part here.
2192 if (P_SHOULDSTOP(p)) {
2193 KASSERT(!(p->p_flag & P_WEXIT),
2194 ("signal to stopped but exiting process"));
2195 if (sig == SIGKILL) {
2197 * If traced process is already stopped,
2198 * then no further action is necessary.
2200 if (p->p_flag & P_TRACED)
2203 * SIGKILL sets process running.
2204 * It will die elsewhere.
2205 * All threads must be restarted.
2207 p->p_flag &= ~P_STOPPED_SIG;
2211 if (prop & SA_CONT) {
2213 * If traced process is already stopped,
2214 * then no further action is necessary.
2216 if (p->p_flag & P_TRACED)
2219 * If SIGCONT is default (or ignored), we continue the
2220 * process but don't leave the signal in sigqueue as
2221 * it has no further action. If SIGCONT is held, we
2222 * continue the process and leave the signal in
2223 * sigqueue. If the process catches SIGCONT, let it
2224 * handle the signal itself. If it isn't waiting on
2225 * an event, it goes back to run state.
2226 * Otherwise, process goes back to sleep state.
2228 p->p_flag &= ~P_STOPPED_SIG;
2230 if (p->p_numthreads == p->p_suspcount) {
2232 p->p_flag |= P_CONTINUED;
2233 p->p_xstat = SIGCONT;
2234 PROC_LOCK(p->p_pptr);
2235 childproc_continued(p);
2236 PROC_UNLOCK(p->p_pptr);
2239 if (action == SIG_DFL) {
2240 thread_unsuspend(p);
2242 sigqueue_delete(sigqueue, sig);
2245 if (action == SIG_CATCH) {
2247 * The process wants to catch it so it needs
2248 * to run at least one thread, but which one?
2254 * The signal is not ignored or caught.
2256 thread_unsuspend(p);
2261 if (prop & SA_STOP) {
2263 * If traced process is already stopped,
2264 * then no further action is necessary.
2266 if (p->p_flag & P_TRACED)
2269 * Already stopped, don't need to stop again
2270 * (If we did the shell could get confused).
2271 * Just make sure the signal STOP bit set.
2273 p->p_flag |= P_STOPPED_SIG;
2274 sigqueue_delete(sigqueue, sig);
2279 * All other kinds of signals:
2280 * If a thread is sleeping interruptibly, simulate a
2281 * wakeup so that when it is continued it will be made
2282 * runnable and can look at the signal. However, don't make
2283 * the PROCESS runnable, leave it stopped.
2284 * It may run a bit until it hits a thread_suspend_check().
2289 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2290 wakeup_swapper = sleepq_abort(td, intrval);
2297 * Mutexes are short lived. Threads waiting on them will
2298 * hit thread_suspend_check() soon.
2300 } else if (p->p_state == PRS_NORMAL) {
2301 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2302 tdsigwakeup(td, sig, action, intrval);
2306 MPASS(action == SIG_DFL);
2308 if (prop & SA_STOP) {
2309 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2311 p->p_flag |= P_STOPPED_SIG;
2314 sig_suspend_threads(td, p, 1);
2315 if (p->p_numthreads == p->p_suspcount) {
2317 * only thread sending signal to another
2318 * process can reach here, if thread is sending
2319 * signal to its process, because thread does
2320 * not suspend itself here, p_numthreads
2321 * should never be equal to p_suspcount.
2325 sigqueue_delete_proc(p, p->p_xstat);
2331 /* Not in "NORMAL" state. discard the signal. */
2332 sigqueue_delete(sigqueue, sig);
2337 * The process is not stopped so we need to apply the signal to all the
2341 tdsigwakeup(td, sig, action, intrval);
2343 thread_unsuspend(p);
2346 /* If we jump here, proc slock should not be owned. */
2347 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2352 * The force of a signal has been directed against a single
2353 * thread. We need to see what we can do about knocking it
2354 * out of any sleep it may be in etc.
2357 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2359 struct proc *p = td->td_proc;
2364 PROC_LOCK_ASSERT(p, MA_OWNED);
2365 prop = sigprop(sig);
2370 * Bring the priority of a thread up if we want it to get
2371 * killed in this lifetime.
2373 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2374 sched_prio(td, PUSER);
2375 if (TD_ON_SLEEPQ(td)) {
2377 * If thread is sleeping uninterruptibly
2378 * we can't interrupt the sleep... the signal will
2379 * be noticed when the process returns through
2380 * trap() or syscall().
2382 if ((td->td_flags & TDF_SINTR) == 0)
2385 * If SIGCONT is default (or ignored) and process is
2386 * asleep, we are finished; the process should not
2389 if ((prop & SA_CONT) && action == SIG_DFL) {
2392 sigqueue_delete(&p->p_sigqueue, sig);
2394 * It may be on either list in this state.
2395 * Remove from both for now.
2397 sigqueue_delete(&td->td_sigqueue, sig);
2402 * Don't awaken a sleeping thread for SIGSTOP if the
2403 * STOP signal is deferred.
2405 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2409 * Give low priority threads a better chance to run.
2411 if (td->td_priority > PUSER)
2412 sched_prio(td, PUSER);
2414 wakeup_swapper = sleepq_abort(td, intrval);
2417 * Other states do nothing with the signal immediately,
2418 * other than kicking ourselves if we are running.
2419 * It will either never be noticed, or noticed very soon.
2422 if (TD_IS_RUNNING(td) && td != curthread)
2434 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2438 PROC_LOCK_ASSERT(p, MA_OWNED);
2439 PROC_SLOCK_ASSERT(p, MA_OWNED);
2441 FOREACH_THREAD_IN_PROC(p, td2) {
2443 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2444 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2445 (td2->td_flags & TDF_SINTR)) {
2446 if (td2->td_flags & TDF_SBDRY) {
2448 * Once a thread is asleep with
2449 * TDF_SBDRY set, it should never
2450 * become suspended due to this check.
2452 KASSERT(!TD_IS_SUSPENDED(td2),
2453 ("thread with deferred stops suspended"));
2454 } else if (!TD_IS_SUSPENDED(td2)) {
2455 thread_suspend_one(td2);
2457 } else if (!TD_IS_SUSPENDED(td2)) {
2458 if (sending || td != td2)
2459 td2->td_flags |= TDF_ASTPENDING;
2461 if (TD_IS_RUNNING(td2) && td2 != td)
2462 forward_signal(td2);
2470 ptracestop(struct thread *td, int sig)
2472 struct proc *p = td->td_proc;
2474 PROC_LOCK_ASSERT(p, MA_OWNED);
2475 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2476 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2477 &p->p_mtx.lock_object, "Stopping for traced signal");
2479 td->td_dbgflags |= TDB_XSIG;
2482 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2483 if (p->p_flag & P_SINGLE_EXIT) {
2484 td->td_dbgflags &= ~TDB_XSIG;
2489 * Just make wait() to work, the last stopped thread
2494 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2495 sig_suspend_threads(td, p, 0);
2496 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2497 td->td_dbgflags &= ~TDB_STOPATFORK;
2498 cv_broadcast(&p->p_dbgwait);
2501 thread_suspend_switch(td, p);
2502 if (p->p_xthread == td)
2503 p->p_xthread = NULL;
2504 if (!(p->p_flag & P_TRACED))
2506 if (td->td_dbgflags & TDB_SUSPEND) {
2507 if (p->p_flag & P_SINGLE_EXIT)
2513 return (td->td_xsig);
2517 reschedule_signals(struct proc *p, sigset_t block, int flags)
2523 PROC_LOCK_ASSERT(p, MA_OWNED);
2525 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2526 MA_OWNED : MA_NOTOWNED);
2527 if (SIGISEMPTY(p->p_siglist))
2529 SIGSETAND(block, p->p_siglist);
2530 while ((sig = sig_ffs(&block)) != 0) {
2531 SIGDELSET(block, sig);
2532 td = sigtd(p, sig, 0);
2534 if (!(flags & SIGPROCMASK_PS_LOCKED))
2535 mtx_lock(&ps->ps_mtx);
2536 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2537 tdsigwakeup(td, sig, SIG_CATCH,
2538 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2540 if (!(flags & SIGPROCMASK_PS_LOCKED))
2541 mtx_unlock(&ps->ps_mtx);
2546 tdsigcleanup(struct thread *td)
2552 PROC_LOCK_ASSERT(p, MA_OWNED);
2554 sigqueue_flush(&td->td_sigqueue);
2555 if (p->p_numthreads == 1)
2559 * Since we cannot handle signals, notify signal post code
2560 * about this by filling the sigmask.
2562 * Also, if needed, wake up thread(s) that do not block the
2563 * same signals as the exiting thread, since the thread might
2564 * have been selected for delivery and woken up.
2566 SIGFILLSET(unblocked);
2567 SIGSETNAND(unblocked, td->td_sigmask);
2568 SIGFILLSET(td->td_sigmask);
2569 reschedule_signals(p, unblocked, 0);
2574 * Defer the delivery of SIGSTOP for the current thread. Returns true
2575 * if stops were deferred and false if they were already deferred.
2583 if (td->td_flags & TDF_SBDRY)
2586 td->td_flags |= TDF_SBDRY;
2592 * Permit the delivery of SIGSTOP for the current thread. This does
2593 * not immediately suspend if a stop was posted. Instead, the thread
2594 * will suspend either via ast() or a subsequent interruptible sleep.
2604 prev = (td->td_flags & TDF_SBDRY) != 0;
2605 td->td_flags &= ~TDF_SBDRY;
2611 * If the current process has received a signal (should be caught or cause
2612 * termination, should interrupt current syscall), return the signal number.
2613 * Stop signals with default action are processed immediately, then cleared;
2614 * they aren't returned. This is checked after each entry to the system for
2615 * a syscall or trap (though this can usually be done without calling issignal
2616 * by checking the pending signal masks in cursig.) The normal call
2619 * while (sig = cursig(curthread))
2623 issignal(struct thread *td)
2627 struct sigqueue *queue;
2628 sigset_t sigpending;
2629 int sig, prop, newsig;
2633 mtx_assert(&ps->ps_mtx, MA_OWNED);
2634 PROC_LOCK_ASSERT(p, MA_OWNED);
2636 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2638 sigpending = td->td_sigqueue.sq_signals;
2639 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2640 SIGSETNAND(sigpending, td->td_sigmask);
2642 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2643 SIG_STOPSIGMASK(sigpending);
2644 if (SIGISEMPTY(sigpending)) /* no signal to send */
2646 sig = sig_ffs(&sigpending);
2648 if (p->p_stops & S_SIG) {
2649 mtx_unlock(&ps->ps_mtx);
2650 stopevent(p, S_SIG, sig);
2651 mtx_lock(&ps->ps_mtx);
2655 * We should see pending but ignored signals
2656 * only if P_TRACED was on when they were posted.
2658 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2659 sigqueue_delete(&td->td_sigqueue, sig);
2660 sigqueue_delete(&p->p_sigqueue, sig);
2663 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) {
2665 * If traced, always stop.
2666 * Remove old signal from queue before the stop.
2667 * XXX shrug off debugger, it causes siginfo to
2670 queue = &td->td_sigqueue;
2671 td->td_dbgksi.ksi_signo = 0;
2672 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2673 queue = &p->p_sigqueue;
2674 sigqueue_get(queue, sig, &td->td_dbgksi);
2677 mtx_unlock(&ps->ps_mtx);
2678 newsig = ptracestop(td, sig);
2679 mtx_lock(&ps->ps_mtx);
2681 if (sig != newsig) {
2684 * If parent wants us to take the signal,
2685 * then it will leave it in p->p_xstat;
2686 * otherwise we just look for signals again.
2693 * Put the new signal into td_sigqueue. If the
2694 * signal is being masked, look for other
2697 sigqueue_add(queue, sig, NULL);
2698 if (SIGISMEMBER(td->td_sigmask, sig))
2702 if (td->td_dbgksi.ksi_signo != 0) {
2703 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2704 if (sigqueue_add(&td->td_sigqueue, sig,
2705 &td->td_dbgksi) != 0)
2706 td->td_dbgksi.ksi_signo = 0;
2708 if (td->td_dbgksi.ksi_signo == 0)
2709 sigqueue_add(&td->td_sigqueue, sig,
2714 * If the traced bit got turned off, go back up
2715 * to the top to rescan signals. This ensures
2716 * that p_sig* and p_sigact are consistent.
2718 if ((p->p_flag & P_TRACED) == 0)
2722 prop = sigprop(sig);
2725 * Decide whether the signal should be returned.
2726 * Return the signal's number, or fall through
2727 * to clear it from the pending mask.
2729 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2731 case (intptr_t)SIG_DFL:
2733 * Don't take default actions on system processes.
2735 if (p->p_pid <= 1) {
2738 * Are you sure you want to ignore SIGSEGV
2741 printf("Process (pid %lu) got signal %d\n",
2742 (u_long)p->p_pid, sig);
2744 break; /* == ignore */
2747 * If there is a pending stop signal to process
2748 * with default action, stop here,
2749 * then clear the signal. However,
2750 * if process is member of an orphaned
2751 * process group, ignore tty stop signals.
2753 if (prop & SA_STOP) {
2754 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2755 (p->p_pgrp->pg_jobc == 0 &&
2757 break; /* == ignore */
2758 mtx_unlock(&ps->ps_mtx);
2759 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2760 &p->p_mtx.lock_object, "Catching SIGSTOP");
2761 p->p_flag |= P_STOPPED_SIG;
2764 sig_suspend_threads(td, p, 0);
2765 thread_suspend_switch(td, p);
2767 mtx_lock(&ps->ps_mtx);
2769 } else if (prop & SA_IGNORE) {
2771 * Except for SIGCONT, shouldn't get here.
2772 * Default action is to ignore; drop it.
2774 break; /* == ignore */
2779 case (intptr_t)SIG_IGN:
2781 * Masking above should prevent us ever trying
2782 * to take action on an ignored signal other
2783 * than SIGCONT, unless process is traced.
2785 if ((prop & SA_CONT) == 0 &&
2786 (p->p_flag & P_TRACED) == 0)
2787 printf("issignal\n");
2788 break; /* == ignore */
2792 * This signal has an action, let
2793 * postsig() process it.
2797 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2798 sigqueue_delete(&p->p_sigqueue, sig);
2804 thread_stopped(struct proc *p)
2808 PROC_LOCK_ASSERT(p, MA_OWNED);
2809 PROC_SLOCK_ASSERT(p, MA_OWNED);
2813 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2815 p->p_flag &= ~P_WAITED;
2816 PROC_LOCK(p->p_pptr);
2817 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2818 CLD_TRAPPED : CLD_STOPPED);
2819 PROC_UNLOCK(p->p_pptr);
2825 * Take the action for the specified signal
2826 * from the current set of pending signals.
2832 struct thread *td = curthread;
2833 register struct proc *p = td->td_proc;
2837 sigset_t returnmask;
2839 KASSERT(sig != 0, ("postsig"));
2841 PROC_LOCK_ASSERT(p, MA_OWNED);
2843 mtx_assert(&ps->ps_mtx, MA_OWNED);
2844 ksiginfo_init(&ksi);
2845 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2846 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2848 ksi.ksi_signo = sig;
2849 if (ksi.ksi_code == SI_TIMER)
2850 itimer_accept(p, ksi.ksi_timerid, &ksi);
2851 action = ps->ps_sigact[_SIG_IDX(sig)];
2853 if (KTRPOINT(td, KTR_PSIG))
2854 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2855 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2857 if (p->p_stops & S_SIG) {
2858 mtx_unlock(&ps->ps_mtx);
2859 stopevent(p, S_SIG, sig);
2860 mtx_lock(&ps->ps_mtx);
2863 if (action == SIG_DFL) {
2865 * Default action, where the default is to kill
2866 * the process. (Other cases were ignored above.)
2868 mtx_unlock(&ps->ps_mtx);
2873 * If we get here, the signal must be caught.
2875 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2876 ("postsig action"));
2878 * Set the new mask value and also defer further
2879 * occurrences of this signal.
2881 * Special case: user has done a sigsuspend. Here the
2882 * current mask is not of interest, but rather the
2883 * mask from before the sigsuspend is what we want
2884 * restored after the signal processing is completed.
2886 if (td->td_pflags & TDP_OLDMASK) {
2887 returnmask = td->td_oldsigmask;
2888 td->td_pflags &= ~TDP_OLDMASK;
2890 returnmask = td->td_sigmask;
2892 if (p->p_sig == sig) {
2896 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2897 postsig_done(sig, td, ps);
2903 * Kill the current process for stated reason.
2911 PROC_LOCK_ASSERT(p, MA_OWNED);
2912 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2914 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2915 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2916 p->p_flag |= P_WKILLED;
2917 kern_psignal(p, SIGKILL);
2921 * Force the current process to exit with the specified signal, dumping core
2922 * if appropriate. We bypass the normal tests for masked and caught signals,
2923 * allowing unrecoverable failures to terminate the process without changing
2924 * signal state. Mark the accounting record with the signal termination.
2925 * If dumping core, save the signal number for the debugger. Calls exit and
2933 struct proc *p = td->td_proc;
2935 PROC_LOCK_ASSERT(p, MA_OWNED);
2936 p->p_acflag |= AXSIG;
2938 * We must be single-threading to generate a core dump. This
2939 * ensures that the registers in the core file are up-to-date.
2940 * Also, the ELF dump handler assumes that the thread list doesn't
2941 * change out from under it.
2943 * XXX If another thread attempts to single-thread before us
2944 * (e.g. via fork()), we won't get a dump at all.
2946 if ((sigprop(sig) & SA_CORE) && thread_single(p, SINGLE_NO_EXIT) == 0) {
2949 * Log signals which would cause core dumps
2950 * (Log as LOG_INFO to appease those who don't want
2952 * XXX : Todo, as well as euid, write out ruid too
2953 * Note that coredump() drops proc lock.
2955 if (coredump(td) == 0)
2957 if (kern_logsigexit)
2959 "pid %d (%s), uid %d: exited on signal %d%s\n",
2960 p->p_pid, p->p_comm,
2961 td->td_ucred ? td->td_ucred->cr_uid : -1,
2963 sig & WCOREFLAG ? " (core dumped)" : "");
2966 exit1(td, W_EXITCODE(0, sig));
2971 * Send queued SIGCHLD to parent when child process's state
2975 sigparent(struct proc *p, int reason, int status)
2977 PROC_LOCK_ASSERT(p, MA_OWNED);
2978 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2980 if (p->p_ksi != NULL) {
2981 p->p_ksi->ksi_signo = SIGCHLD;
2982 p->p_ksi->ksi_code = reason;
2983 p->p_ksi->ksi_status = status;
2984 p->p_ksi->ksi_pid = p->p_pid;
2985 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2986 if (KSI_ONQ(p->p_ksi))
2989 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2993 childproc_jobstate(struct proc *p, int reason, int sig)
2997 PROC_LOCK_ASSERT(p, MA_OWNED);
2998 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3001 * Wake up parent sleeping in kern_wait(), also send
3002 * SIGCHLD to parent, but SIGCHLD does not guarantee
3003 * that parent will awake, because parent may masked
3006 p->p_pptr->p_flag |= P_STATCHILD;
3009 ps = p->p_pptr->p_sigacts;
3010 mtx_lock(&ps->ps_mtx);
3011 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3012 mtx_unlock(&ps->ps_mtx);
3013 sigparent(p, reason, sig);
3015 mtx_unlock(&ps->ps_mtx);
3019 childproc_stopped(struct proc *p, int reason)
3021 /* p_xstat is a plain signal number, not a full wait() status here. */
3022 childproc_jobstate(p, reason, p->p_xstat);
3026 childproc_continued(struct proc *p)
3028 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3032 childproc_exited(struct proc *p)
3035 int xstat = p->p_xstat; /* convert to int */
3038 if (WCOREDUMP(xstat))
3039 reason = CLD_DUMPED, status = WTERMSIG(xstat);
3040 else if (WIFSIGNALED(xstat))
3041 reason = CLD_KILLED, status = WTERMSIG(xstat);
3043 reason = CLD_EXITED, status = WEXITSTATUS(xstat);
3045 * XXX avoid calling wakeup(p->p_pptr), the work is
3048 sigparent(p, reason, status);
3052 * We only have 1 character for the core count in the format
3053 * string, so the range will be 0-9
3055 #define MAX_NUM_CORES 10
3056 static int num_cores = 5;
3059 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3064 new_val = num_cores;
3065 error = sysctl_handle_int(oidp, &new_val, 0, req);
3066 if (error != 0 || req->newptr == NULL)
3068 if (new_val > MAX_NUM_CORES)
3069 new_val = MAX_NUM_CORES;
3072 num_cores = new_val;
3075 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3076 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3078 #define GZ_SUFFIX ".gz"
3081 static int compress_user_cores = 1;
3082 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RWTUN,
3083 &compress_user_cores, 0, "Compression of user corefiles");
3085 int compress_user_cores_gzlevel = 6;
3086 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RWTUN,
3087 &compress_user_cores_gzlevel, 0, "Corefile gzip compression level");
3089 static int compress_user_cores = 0;
3093 * Protect the access to corefilename[] by allproc_lock.
3095 #define corefilename_lock allproc_lock
3097 static char corefilename[MAXPATHLEN] = {"%N.core"};
3100 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3104 sx_xlock(&corefilename_lock);
3105 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3107 sx_xunlock(&corefilename_lock);
3111 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RWTUN |
3112 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3113 "Process corefile name format string");
3116 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3117 * Expand the name described in corefilename, using name, uid, and pid
3118 * and open/create core file.
3119 * corefilename is a printf-like string, with three format specifiers:
3120 * %N name of process ("name")
3121 * %P process id (pid)
3123 * For example, "%N.core" is the default; they can be disabled completely
3124 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3125 * This is controlled by the sysctl variable kern.corefile (see above).
3128 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3129 int compress, struct vnode **vpp, char **namep)
3131 struct nameidata nd;
3134 char *hostname, *name;
3135 int indexpos, i, error, cmode, flags, oflags;
3138 format = corefilename;
3139 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3141 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3142 sx_slock(&corefilename_lock);
3143 for (i = 0; format[i] != '\0'; i++) {
3144 switch (format[i]) {
3145 case '%': /* Format character */
3147 switch (format[i]) {
3149 sbuf_putc(&sb, '%');
3151 case 'H': /* hostname */
3152 if (hostname == NULL) {
3153 hostname = malloc(MAXHOSTNAMELEN,
3156 getcredhostname(td->td_ucred, hostname,
3158 sbuf_printf(&sb, "%s", hostname);
3160 case 'I': /* autoincrementing index */
3161 sbuf_printf(&sb, "0");
3162 indexpos = sbuf_len(&sb) - 1;
3164 case 'N': /* process name */
3165 sbuf_printf(&sb, "%s", comm);
3167 case 'P': /* process id */
3168 sbuf_printf(&sb, "%u", pid);
3170 case 'U': /* user id */
3171 sbuf_printf(&sb, "%u", uid);
3175 "Unknown format character %c in "
3176 "corename `%s'\n", format[i], format);
3181 sbuf_putc(&sb, format[i]);
3185 sx_sunlock(&corefilename_lock);
3186 free(hostname, M_TEMP);
3188 sbuf_printf(&sb, GZ_SUFFIX);
3189 if (sbuf_error(&sb) != 0) {
3190 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3191 "long\n", (long)pid, comm, (u_long)uid);
3199 cmode = S_IRUSR | S_IWUSR;
3200 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3201 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3204 * If the core format has a %I in it, then we need to check
3205 * for existing corefiles before returning a name.
3206 * To do this we iterate over 0..num_cores to find a
3207 * non-existing core file name to use.
3209 if (indexpos != -1) {
3210 for (i = 0; i < num_cores; i++) {
3211 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3212 name[indexpos] = '0' + i;
3213 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3214 error = vn_open_cred(&nd, &flags, cmode, oflags,
3215 td->td_ucred, NULL);
3217 if (error == EEXIST)
3220 "pid %d (%s), uid (%u): Path `%s' failed "
3221 "on initial open test, error = %d\n",
3222 pid, comm, uid, name, error);
3228 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3229 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3230 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3234 audit_proc_coredump(td, name, error);
3239 NDFREE(&nd, NDF_ONLY_PNBUF);
3246 coredump_sanitise_path(const char *path)
3251 * Only send a subset of ASCII to devd(8) because it
3252 * might pass these strings to sh -c.
3254 for (i = 0; path[i]; i++)
3255 if (!(isalpha(path[i]) || isdigit(path[i])) &&
3256 path[i] != '/' && path[i] != '.' &&
3264 * Dump a process' core. The main routine does some
3265 * policy checking, and creates the name of the coredump;
3266 * then it passes on a vnode and a size limit to the process-specific
3267 * coredump routine if there is one; if there _is not_ one, it returns
3268 * ENOSYS; otherwise it returns the error from the process-specific routine.
3272 coredump(struct thread *td)
3274 struct proc *p = td->td_proc;
3275 struct ucred *cred = td->td_ucred;
3279 int error, error1, locked;
3280 char *name; /* name of corefile */
3284 char *fullpath, *freepath = NULL;
3286 static const char comm_name[] = "comm=";
3287 static const char core_name[] = "core=";
3289 PROC_LOCK_ASSERT(p, MA_OWNED);
3290 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3291 _STOPEVENT(p, S_CORE, 0);
3293 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3294 (p->p_flag2 & P2_NOTRACE) != 0) {
3300 * Note that the bulk of limit checking is done after
3301 * the corefile is created. The exception is if the limit
3302 * for corefiles is 0, in which case we don't bother
3303 * creating the corefile at all. This layout means that
3304 * a corefile is truncated instead of not being created,
3305 * if it is larger than the limit.
3307 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3308 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3314 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3315 compress_user_cores, &vp, &name);
3320 * Don't dump to non-regular files or files with links.
3321 * Do not dump into system files.
3323 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3324 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0) {
3332 /* Postpone other writers, including core dumps of other processes. */
3333 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3335 lf.l_whence = SEEK_SET;
3338 lf.l_type = F_WRLCK;
3339 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3343 if (set_core_nodump_flag)
3344 vattr.va_flags = UF_NODUMP;
3345 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3346 VOP_SETATTR(vp, &vattr, cred);
3349 p->p_acflag |= ACORE;
3352 if (p->p_sysent->sv_coredump != NULL) {
3353 error = p->p_sysent->sv_coredump(td, vp, limit,
3354 compress_user_cores ? IMGACT_CORE_COMPRESS : 0);
3360 lf.l_type = F_UNLCK;
3361 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3363 vn_rangelock_unlock(vp, rl_cookie);
3366 * Notify the userland helper that a process triggered a core dump.
3367 * This allows the helper to run an automated debugging session.
3369 if (error != 0 || coredump_devctl == 0)
3371 len = MAXPATHLEN * 2 + sizeof(comm_name) - 1 +
3372 sizeof(' ') + sizeof(core_name) - 1;
3373 data = malloc(len, M_TEMP, M_WAITOK);
3374 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3376 if (!coredump_sanitise_path(fullpath))
3378 snprintf(data, len, "%s%s ", comm_name, fullpath);
3379 free(freepath, M_TEMP);
3381 if (vn_fullpath_global(td, vp, &fullpath, &freepath) != 0)
3383 if (!coredump_sanitise_path(fullpath))
3385 strlcat(data, core_name, len);
3386 strlcat(data, fullpath, len);
3387 devctl_notify("kernel", "signal", "coredump", data);
3389 error1 = vn_close(vp, FWRITE, cred, td);
3393 audit_proc_coredump(td, name, error);
3395 free(freepath, M_TEMP);
3402 * Nonexistent system call-- signal process (may want to handle it). Flag
3403 * error in case process won't see signal immediately (blocked or ignored).
3405 #ifndef _SYS_SYSPROTO_H_
3414 struct nosys_args *args;
3416 struct proc *p = td->td_proc;
3419 tdsignal(td, SIGSYS);
3425 * Send a SIGIO or SIGURG signal to a process or process group using stored
3426 * credentials rather than those of the current process.
3429 pgsigio(sigiop, sig, checkctty)
3430 struct sigio **sigiop;
3434 struct sigio *sigio;
3436 ksiginfo_init(&ksi);
3437 ksi.ksi_signo = sig;
3438 ksi.ksi_code = SI_KERNEL;
3442 if (sigio == NULL) {
3446 if (sigio->sio_pgid > 0) {
3447 PROC_LOCK(sigio->sio_proc);
3448 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3449 kern_psignal(sigio->sio_proc, sig);
3450 PROC_UNLOCK(sigio->sio_proc);
3451 } else if (sigio->sio_pgid < 0) {
3454 PGRP_LOCK(sigio->sio_pgrp);
3455 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3457 if (p->p_state == PRS_NORMAL &&
3458 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3459 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3460 kern_psignal(p, sig);
3463 PGRP_UNLOCK(sigio->sio_pgrp);
3469 filt_sigattach(struct knote *kn)
3471 struct proc *p = curproc;
3473 kn->kn_ptr.p_proc = p;
3474 kn->kn_flags |= EV_CLEAR; /* automatically set */
3476 knlist_add(&p->p_klist, kn, 0);
3482 filt_sigdetach(struct knote *kn)
3484 struct proc *p = kn->kn_ptr.p_proc;
3486 knlist_remove(&p->p_klist, kn, 0);
3490 * signal knotes are shared with proc knotes, so we apply a mask to
3491 * the hint in order to differentiate them from process hints. This
3492 * could be avoided by using a signal-specific knote list, but probably
3493 * isn't worth the trouble.
3496 filt_signal(struct knote *kn, long hint)
3499 if (hint & NOTE_SIGNAL) {
3500 hint &= ~NOTE_SIGNAL;
3502 if (kn->kn_id == hint)
3505 return (kn->kn_data != 0);
3513 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3514 refcount_init(&ps->ps_refcnt, 1);
3515 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3520 sigacts_free(struct sigacts *ps)
3523 if (refcount_release(&ps->ps_refcnt) == 0)
3525 mtx_destroy(&ps->ps_mtx);
3526 free(ps, M_SUBPROC);
3530 sigacts_hold(struct sigacts *ps)
3533 refcount_acquire(&ps->ps_refcnt);
3538 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3541 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3542 mtx_lock(&src->ps_mtx);
3543 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3544 mtx_unlock(&src->ps_mtx);
3548 sigacts_shared(struct sigacts *ps)
3551 return (ps->ps_refcnt > 1);