2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
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11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
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19 * may be used to endorse or promote products derived from this software
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34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
41 #include "opt_kdtrace.h"
42 #include "opt_ktrace.h"
44 #include "opt_procdesc.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/signalvar.h>
49 #include <sys/vnode.h>
51 #include <sys/capability.h>
52 #include <sys/condvar.h>
53 #include <sys/event.h>
54 #include <sys/fcntl.h>
55 #include <sys/imgact.h>
56 #include <sys/kernel.h>
58 #include <sys/ktrace.h>
60 #include <sys/malloc.h>
61 #include <sys/mutex.h>
62 #include <sys/refcount.h>
63 #include <sys/namei.h>
65 #include <sys/procdesc.h>
66 #include <sys/posix4.h>
67 #include <sys/pioctl.h>
68 #include <sys/racct.h>
69 #include <sys/resourcevar.h>
72 #include <sys/sleepqueue.h>
76 #include <sys/syscallsubr.h>
77 #include <sys/sysctl.h>
78 #include <sys/sysent.h>
79 #include <sys/syslog.h>
80 #include <sys/sysproto.h>
81 #include <sys/timers.h>
82 #include <sys/unistd.h>
85 #include <vm/vm_extern.h>
90 #include <machine/cpu.h>
92 #include <security/audit/audit.h>
94 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE3(proc, kernel, , signal__send, "struct thread *",
98 "struct proc *", "int");
99 SDT_PROBE_DEFINE2(proc, kernel, , signal__clear, "int",
101 SDT_PROBE_DEFINE3(proc, kernel, , signal__discard,
102 "struct thread *", "struct proc *", "int");
104 static int coredump(struct thread *);
105 static int killpg1(struct thread *td, int sig, int pgid, int all,
107 static int issignal(struct thread *td);
108 static int sigprop(int sig);
109 static void tdsigwakeup(struct thread *, int, sig_t, int);
110 static void sig_suspend_threads(struct thread *, struct proc *, int);
111 static int filt_sigattach(struct knote *kn);
112 static void filt_sigdetach(struct knote *kn);
113 static int filt_signal(struct knote *kn, long hint);
114 static struct thread *sigtd(struct proc *p, int sig, int prop);
115 static void sigqueue_start(void);
117 static uma_zone_t ksiginfo_zone = NULL;
118 struct filterops sig_filtops = {
120 .f_attach = filt_sigattach,
121 .f_detach = filt_sigdetach,
122 .f_event = filt_signal,
125 static int kern_logsigexit = 1;
126 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
128 "Log processes quitting on abnormal signals to syslog(3)");
130 static int kern_forcesigexit = 1;
131 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
132 &kern_forcesigexit, 0, "Force trap signal to be handled");
134 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
135 "POSIX real time signal");
137 static int max_pending_per_proc = 128;
138 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
139 &max_pending_per_proc, 0, "Max pending signals per proc");
141 static int preallocate_siginfo = 1024;
142 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
143 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
144 &preallocate_siginfo, 0, "Preallocated signal memory size");
146 static int signal_overflow = 0;
147 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
148 &signal_overflow, 0, "Number of signals overflew");
150 static int signal_alloc_fail = 0;
151 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
152 &signal_alloc_fail, 0, "signals failed to be allocated");
154 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
157 * Policy -- Can ucred cr1 send SIGIO to process cr2?
158 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
159 * in the right situations.
161 #define CANSIGIO(cr1, cr2) \
162 ((cr1)->cr_uid == 0 || \
163 (cr1)->cr_ruid == (cr2)->cr_ruid || \
164 (cr1)->cr_uid == (cr2)->cr_ruid || \
165 (cr1)->cr_ruid == (cr2)->cr_uid || \
166 (cr1)->cr_uid == (cr2)->cr_uid)
168 static int sugid_coredump;
169 TUNABLE_INT("kern.sugid_coredump", &sugid_coredump);
170 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
171 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
173 static int capmode_coredump;
174 TUNABLE_INT("kern.capmode_coredump", &capmode_coredump);
175 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RW,
176 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
178 static int do_coredump = 1;
179 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
180 &do_coredump, 0, "Enable/Disable coredumps");
182 static int set_core_nodump_flag = 0;
183 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
184 0, "Enable setting the NODUMP flag on coredump files");
187 * Signal properties and actions.
188 * The array below categorizes the signals and their default actions
189 * according to the following properties:
191 #define SA_KILL 0x01 /* terminates process by default */
192 #define SA_CORE 0x02 /* ditto and coredumps */
193 #define SA_STOP 0x04 /* suspend process */
194 #define SA_TTYSTOP 0x08 /* ditto, from tty */
195 #define SA_IGNORE 0x10 /* ignore by default */
196 #define SA_CONT 0x20 /* continue if suspended */
197 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
199 static int sigproptbl[NSIG] = {
200 SA_KILL, /* SIGHUP */
201 SA_KILL, /* SIGINT */
202 SA_KILL|SA_CORE, /* SIGQUIT */
203 SA_KILL|SA_CORE, /* SIGILL */
204 SA_KILL|SA_CORE, /* SIGTRAP */
205 SA_KILL|SA_CORE, /* SIGABRT */
206 SA_KILL|SA_CORE, /* SIGEMT */
207 SA_KILL|SA_CORE, /* SIGFPE */
208 SA_KILL, /* SIGKILL */
209 SA_KILL|SA_CORE, /* SIGBUS */
210 SA_KILL|SA_CORE, /* SIGSEGV */
211 SA_KILL|SA_CORE, /* SIGSYS */
212 SA_KILL, /* SIGPIPE */
213 SA_KILL, /* SIGALRM */
214 SA_KILL, /* SIGTERM */
215 SA_IGNORE, /* SIGURG */
216 SA_STOP, /* SIGSTOP */
217 SA_STOP|SA_TTYSTOP, /* SIGTSTP */
218 SA_IGNORE|SA_CONT, /* SIGCONT */
219 SA_IGNORE, /* SIGCHLD */
220 SA_STOP|SA_TTYSTOP, /* SIGTTIN */
221 SA_STOP|SA_TTYSTOP, /* SIGTTOU */
222 SA_IGNORE, /* SIGIO */
223 SA_KILL, /* SIGXCPU */
224 SA_KILL, /* SIGXFSZ */
225 SA_KILL, /* SIGVTALRM */
226 SA_KILL, /* SIGPROF */
227 SA_IGNORE, /* SIGWINCH */
228 SA_IGNORE, /* SIGINFO */
229 SA_KILL, /* SIGUSR1 */
230 SA_KILL, /* SIGUSR2 */
233 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
238 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
239 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
240 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
241 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
242 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
243 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
247 ksiginfo_alloc(int wait)
254 if (ksiginfo_zone != NULL)
255 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
260 ksiginfo_free(ksiginfo_t *ksi)
262 uma_zfree(ksiginfo_zone, ksi);
266 ksiginfo_tryfree(ksiginfo_t *ksi)
268 if (!(ksi->ksi_flags & KSI_EXT)) {
269 uma_zfree(ksiginfo_zone, ksi);
276 sigqueue_init(sigqueue_t *list, struct proc *p)
278 SIGEMPTYSET(list->sq_signals);
279 SIGEMPTYSET(list->sq_kill);
280 TAILQ_INIT(&list->sq_list);
282 list->sq_flags = SQ_INIT;
286 * Get a signal's ksiginfo.
288 * 0 - signal not found
289 * others - signal number
292 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
294 struct proc *p = sq->sq_proc;
295 struct ksiginfo *ksi, *next;
298 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
300 if (!SIGISMEMBER(sq->sq_signals, signo))
303 if (SIGISMEMBER(sq->sq_kill, signo)) {
305 SIGDELSET(sq->sq_kill, signo);
308 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
309 if (ksi->ksi_signo == signo) {
311 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
312 ksi->ksi_sigq = NULL;
313 ksiginfo_copy(ksi, si);
314 if (ksiginfo_tryfree(ksi) && p != NULL)
323 SIGDELSET(sq->sq_signals, signo);
324 si->ksi_signo = signo;
329 sigqueue_take(ksiginfo_t *ksi)
335 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
339 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
340 ksi->ksi_sigq = NULL;
341 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
344 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
345 kp = TAILQ_NEXT(kp, ksi_link)) {
346 if (kp->ksi_signo == ksi->ksi_signo)
349 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
350 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
354 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
356 struct proc *p = sq->sq_proc;
357 struct ksiginfo *ksi;
360 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
362 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
363 SIGADDSET(sq->sq_kill, signo);
367 /* directly insert the ksi, don't copy it */
368 if (si->ksi_flags & KSI_INS) {
369 if (si->ksi_flags & KSI_HEAD)
370 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
372 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
377 if (__predict_false(ksiginfo_zone == NULL)) {
378 SIGADDSET(sq->sq_kill, signo);
382 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
385 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
391 ksiginfo_copy(si, ksi);
392 ksi->ksi_signo = signo;
393 if (si->ksi_flags & KSI_HEAD)
394 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
396 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
400 if ((si->ksi_flags & KSI_TRAP) != 0 ||
401 (si->ksi_flags & KSI_SIGQ) == 0) {
403 SIGADDSET(sq->sq_kill, signo);
412 SIGADDSET(sq->sq_signals, signo);
417 sigqueue_flush(sigqueue_t *sq)
419 struct proc *p = sq->sq_proc;
422 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
425 PROC_LOCK_ASSERT(p, MA_OWNED);
427 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
428 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
429 ksi->ksi_sigq = NULL;
430 if (ksiginfo_tryfree(ksi) && p != NULL)
434 SIGEMPTYSET(sq->sq_signals);
435 SIGEMPTYSET(sq->sq_kill);
439 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
442 struct proc *p1, *p2;
443 ksiginfo_t *ksi, *next;
445 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
446 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
449 /* Move siginfo to target list */
450 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
451 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
452 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
455 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
462 /* Move pending bits to target list */
464 SIGSETAND(tmp, *set);
465 SIGSETOR(dst->sq_kill, tmp);
466 SIGSETNAND(src->sq_kill, tmp);
468 tmp = src->sq_signals;
469 SIGSETAND(tmp, *set);
470 SIGSETOR(dst->sq_signals, tmp);
471 SIGSETNAND(src->sq_signals, tmp);
476 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
481 SIGADDSET(set, signo);
482 sigqueue_move_set(src, dst, &set);
487 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
489 struct proc *p = sq->sq_proc;
490 ksiginfo_t *ksi, *next;
492 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
494 /* Remove siginfo queue */
495 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
496 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
497 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
498 ksi->ksi_sigq = NULL;
499 if (ksiginfo_tryfree(ksi) && p != NULL)
503 SIGSETNAND(sq->sq_kill, *set);
504 SIGSETNAND(sq->sq_signals, *set);
508 sigqueue_delete(sigqueue_t *sq, int signo)
513 SIGADDSET(set, signo);
514 sigqueue_delete_set(sq, &set);
517 /* Remove a set of signals for a process */
519 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
524 PROC_LOCK_ASSERT(p, MA_OWNED);
526 sigqueue_init(&worklist, NULL);
527 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
529 FOREACH_THREAD_IN_PROC(p, td0)
530 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
532 sigqueue_flush(&worklist);
536 sigqueue_delete_proc(struct proc *p, int signo)
541 SIGADDSET(set, signo);
542 sigqueue_delete_set_proc(p, &set);
546 sigqueue_delete_stopmask_proc(struct proc *p)
551 SIGADDSET(set, SIGSTOP);
552 SIGADDSET(set, SIGTSTP);
553 SIGADDSET(set, SIGTTIN);
554 SIGADDSET(set, SIGTTOU);
555 sigqueue_delete_set_proc(p, &set);
559 * Determine signal that should be delivered to thread td, the current
560 * thread, 0 if none. If there is a pending stop signal with default
561 * action, the process stops in issignal().
564 cursig(struct thread *td)
566 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
567 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
568 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
569 return (SIGPENDING(td) ? issignal(td) : 0);
573 * Arrange for ast() to handle unmasked pending signals on return to user
574 * mode. This must be called whenever a signal is added to td_sigqueue or
575 * unmasked in td_sigmask.
578 signotify(struct thread *td)
584 PROC_LOCK_ASSERT(p, MA_OWNED);
586 if (SIGPENDING(td)) {
588 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
594 sigonstack(size_t sp)
596 struct thread *td = curthread;
598 return ((td->td_pflags & TDP_ALTSTACK) ?
599 #if defined(COMPAT_43)
600 ((td->td_sigstk.ss_size == 0) ?
601 (td->td_sigstk.ss_flags & SS_ONSTACK) :
602 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
604 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
613 if (sig > 0 && sig < NSIG)
614 return (sigproptbl[_SIG_IDX(sig)]);
619 sig_ffs(sigset_t *set)
623 for (i = 0; i < _SIG_WORDS; i++)
625 return (ffs(set->__bits[i]) + (i * 32));
630 sigact_flag_test(struct sigaction *act, int flag)
634 * SA_SIGINFO is reset when signal disposition is set to
635 * ignore or default. Other flags are kept according to user
638 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
639 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
640 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
650 kern_sigaction(td, sig, act, oact, flags)
653 struct sigaction *act, *oact;
657 struct proc *p = td->td_proc;
659 if (!_SIG_VALID(sig))
661 if (act != NULL && (act->sa_flags & ~(SA_ONSTACK | SA_RESTART |
662 SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER | SA_NOCLDWAIT |
668 mtx_lock(&ps->ps_mtx);
670 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
672 if (SIGISMEMBER(ps->ps_sigonstack, sig))
673 oact->sa_flags |= SA_ONSTACK;
674 if (!SIGISMEMBER(ps->ps_sigintr, sig))
675 oact->sa_flags |= SA_RESTART;
676 if (SIGISMEMBER(ps->ps_sigreset, sig))
677 oact->sa_flags |= SA_RESETHAND;
678 if (SIGISMEMBER(ps->ps_signodefer, sig))
679 oact->sa_flags |= SA_NODEFER;
680 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
681 oact->sa_flags |= SA_SIGINFO;
683 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
685 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
686 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
687 oact->sa_flags |= SA_NOCLDSTOP;
688 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
689 oact->sa_flags |= SA_NOCLDWAIT;
692 if ((sig == SIGKILL || sig == SIGSTOP) &&
693 act->sa_handler != SIG_DFL) {
694 mtx_unlock(&ps->ps_mtx);
700 * Change setting atomically.
703 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
704 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
705 if (sigact_flag_test(act, SA_SIGINFO)) {
706 ps->ps_sigact[_SIG_IDX(sig)] =
707 (__sighandler_t *)act->sa_sigaction;
708 SIGADDSET(ps->ps_siginfo, sig);
710 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
711 SIGDELSET(ps->ps_siginfo, sig);
713 if (!sigact_flag_test(act, SA_RESTART))
714 SIGADDSET(ps->ps_sigintr, sig);
716 SIGDELSET(ps->ps_sigintr, sig);
717 if (sigact_flag_test(act, SA_ONSTACK))
718 SIGADDSET(ps->ps_sigonstack, sig);
720 SIGDELSET(ps->ps_sigonstack, sig);
721 if (sigact_flag_test(act, SA_RESETHAND))
722 SIGADDSET(ps->ps_sigreset, sig);
724 SIGDELSET(ps->ps_sigreset, sig);
725 if (sigact_flag_test(act, SA_NODEFER))
726 SIGADDSET(ps->ps_signodefer, sig);
728 SIGDELSET(ps->ps_signodefer, sig);
729 if (sig == SIGCHLD) {
730 if (act->sa_flags & SA_NOCLDSTOP)
731 ps->ps_flag |= PS_NOCLDSTOP;
733 ps->ps_flag &= ~PS_NOCLDSTOP;
734 if (act->sa_flags & SA_NOCLDWAIT) {
736 * Paranoia: since SA_NOCLDWAIT is implemented
737 * by reparenting the dying child to PID 1 (and
738 * trust it to reap the zombie), PID 1 itself
739 * is forbidden to set SA_NOCLDWAIT.
742 ps->ps_flag &= ~PS_NOCLDWAIT;
744 ps->ps_flag |= PS_NOCLDWAIT;
746 ps->ps_flag &= ~PS_NOCLDWAIT;
747 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
748 ps->ps_flag |= PS_CLDSIGIGN;
750 ps->ps_flag &= ~PS_CLDSIGIGN;
753 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
754 * and for signals set to SIG_DFL where the default is to
755 * ignore. However, don't put SIGCONT in ps_sigignore, as we
756 * have to restart the process.
758 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
759 (sigprop(sig) & SA_IGNORE &&
760 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
761 /* never to be seen again */
762 sigqueue_delete_proc(p, sig);
764 /* easier in psignal */
765 SIGADDSET(ps->ps_sigignore, sig);
766 SIGDELSET(ps->ps_sigcatch, sig);
768 SIGDELSET(ps->ps_sigignore, sig);
769 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
770 SIGDELSET(ps->ps_sigcatch, sig);
772 SIGADDSET(ps->ps_sigcatch, sig);
774 #ifdef COMPAT_FREEBSD4
775 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
776 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
777 (flags & KSA_FREEBSD4) == 0)
778 SIGDELSET(ps->ps_freebsd4, sig);
780 SIGADDSET(ps->ps_freebsd4, sig);
783 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
784 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
785 (flags & KSA_OSIGSET) == 0)
786 SIGDELSET(ps->ps_osigset, sig);
788 SIGADDSET(ps->ps_osigset, sig);
791 mtx_unlock(&ps->ps_mtx);
796 #ifndef _SYS_SYSPROTO_H_
797 struct sigaction_args {
799 struct sigaction *act;
800 struct sigaction *oact;
804 sys_sigaction(td, uap)
806 register struct sigaction_args *uap;
808 struct sigaction act, oact;
809 register struct sigaction *actp, *oactp;
812 actp = (uap->act != NULL) ? &act : NULL;
813 oactp = (uap->oact != NULL) ? &oact : NULL;
815 error = copyin(uap->act, actp, sizeof(act));
819 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
821 error = copyout(oactp, uap->oact, sizeof(oact));
825 #ifdef COMPAT_FREEBSD4
826 #ifndef _SYS_SYSPROTO_H_
827 struct freebsd4_sigaction_args {
829 struct sigaction *act;
830 struct sigaction *oact;
834 freebsd4_sigaction(td, uap)
836 register struct freebsd4_sigaction_args *uap;
838 struct sigaction act, oact;
839 register struct sigaction *actp, *oactp;
843 actp = (uap->act != NULL) ? &act : NULL;
844 oactp = (uap->oact != NULL) ? &oact : NULL;
846 error = copyin(uap->act, actp, sizeof(act));
850 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
852 error = copyout(oactp, uap->oact, sizeof(oact));
855 #endif /* COMAPT_FREEBSD4 */
857 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
858 #ifndef _SYS_SYSPROTO_H_
859 struct osigaction_args {
861 struct osigaction *nsa;
862 struct osigaction *osa;
868 register struct osigaction_args *uap;
870 struct osigaction sa;
871 struct sigaction nsa, osa;
872 register struct sigaction *nsap, *osap;
875 if (uap->signum <= 0 || uap->signum >= ONSIG)
878 nsap = (uap->nsa != NULL) ? &nsa : NULL;
879 osap = (uap->osa != NULL) ? &osa : NULL;
882 error = copyin(uap->nsa, &sa, sizeof(sa));
885 nsap->sa_handler = sa.sa_handler;
886 nsap->sa_flags = sa.sa_flags;
887 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
889 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
890 if (osap && !error) {
891 sa.sa_handler = osap->sa_handler;
892 sa.sa_flags = osap->sa_flags;
893 SIG2OSIG(osap->sa_mask, sa.sa_mask);
894 error = copyout(&sa, uap->osa, sizeof(sa));
899 #if !defined(__i386__)
900 /* Avoid replicating the same stub everywhere */
904 struct osigreturn_args *uap;
907 return (nosys(td, (struct nosys_args *)uap));
910 #endif /* COMPAT_43 */
913 * Initialize signal state for process 0;
914 * set to ignore signals that are ignored by default.
925 mtx_lock(&ps->ps_mtx);
926 for (i = 1; i <= NSIG; i++) {
927 if (sigprop(i) & SA_IGNORE && i != SIGCONT) {
928 SIGADDSET(ps->ps_sigignore, i);
931 mtx_unlock(&ps->ps_mtx);
936 * Reset specified signal to the default disposition.
939 sigdflt(struct sigacts *ps, int sig)
942 mtx_assert(&ps->ps_mtx, MA_OWNED);
943 SIGDELSET(ps->ps_sigcatch, sig);
944 if ((sigprop(sig) & SA_IGNORE) != 0 && sig != SIGCONT)
945 SIGADDSET(ps->ps_sigignore, sig);
946 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
947 SIGDELSET(ps->ps_siginfo, sig);
951 * Reset signals for an exec of the specified process.
954 execsigs(struct proc *p)
961 * Reset caught signals. Held signals remain held
962 * through td_sigmask (unless they were caught,
963 * and are now ignored by default).
965 PROC_LOCK_ASSERT(p, MA_OWNED);
966 td = FIRST_THREAD_IN_PROC(p);
968 mtx_lock(&ps->ps_mtx);
969 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
970 sig = sig_ffs(&ps->ps_sigcatch);
972 if ((sigprop(sig) & SA_IGNORE) != 0)
973 sigqueue_delete_proc(p, sig);
976 * Reset stack state to the user stack.
977 * Clear set of signals caught on the signal stack.
979 td->td_sigstk.ss_flags = SS_DISABLE;
980 td->td_sigstk.ss_size = 0;
981 td->td_sigstk.ss_sp = 0;
982 td->td_pflags &= ~TDP_ALTSTACK;
984 * Reset no zombies if child dies flag as Solaris does.
986 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
987 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
988 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
989 mtx_unlock(&ps->ps_mtx);
995 * Manipulate signal mask.
998 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1001 sigset_t new_block, oset1;
1006 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1007 PROC_LOCK_ASSERT(p, MA_OWNED);
1010 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1011 ? MA_OWNED : MA_NOTOWNED);
1013 *oset = td->td_sigmask;
1020 oset1 = td->td_sigmask;
1021 SIGSETOR(td->td_sigmask, *set);
1022 new_block = td->td_sigmask;
1023 SIGSETNAND(new_block, oset1);
1026 SIGSETNAND(td->td_sigmask, *set);
1031 oset1 = td->td_sigmask;
1032 if (flags & SIGPROCMASK_OLD)
1033 SIGSETLO(td->td_sigmask, *set);
1035 td->td_sigmask = *set;
1036 new_block = td->td_sigmask;
1037 SIGSETNAND(new_block, oset1);
1046 * The new_block set contains signals that were not previously
1047 * blocked, but are blocked now.
1049 * In case we block any signal that was not previously blocked
1050 * for td, and process has the signal pending, try to schedule
1051 * signal delivery to some thread that does not block the
1052 * signal, possibly waking it up.
1054 if (p->p_numthreads != 1)
1055 reschedule_signals(p, new_block, flags);
1059 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1064 #ifndef _SYS_SYSPROTO_H_
1065 struct sigprocmask_args {
1067 const sigset_t *set;
1072 sys_sigprocmask(td, uap)
1073 register struct thread *td;
1074 struct sigprocmask_args *uap;
1077 sigset_t *setp, *osetp;
1080 setp = (uap->set != NULL) ? &set : NULL;
1081 osetp = (uap->oset != NULL) ? &oset : NULL;
1083 error = copyin(uap->set, setp, sizeof(set));
1087 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1088 if (osetp && !error) {
1089 error = copyout(osetp, uap->oset, sizeof(oset));
1094 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1095 #ifndef _SYS_SYSPROTO_H_
1096 struct osigprocmask_args {
1102 osigprocmask(td, uap)
1103 register struct thread *td;
1104 struct osigprocmask_args *uap;
1109 OSIG2SIG(uap->mask, set);
1110 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1111 SIG2OSIG(oset, td->td_retval[0]);
1114 #endif /* COMPAT_43 */
1117 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1123 error = copyin(uap->set, &set, sizeof(set));
1125 td->td_retval[0] = error;
1129 error = kern_sigtimedwait(td, set, &ksi, NULL);
1131 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1133 if (error == ERESTART)
1135 td->td_retval[0] = error;
1139 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1140 td->td_retval[0] = error;
1145 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1148 struct timespec *timeout;
1154 error = copyin(uap->timeout, &ts, sizeof(ts));
1162 error = copyin(uap->set, &set, sizeof(set));
1166 error = kern_sigtimedwait(td, set, &ksi, timeout);
1171 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1174 td->td_retval[0] = ksi.ksi_signo;
1179 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1185 error = copyin(uap->set, &set, sizeof(set));
1189 error = kern_sigtimedwait(td, set, &ksi, NULL);
1194 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1197 td->td_retval[0] = ksi.ksi_signo;
1202 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1203 struct timespec *timeout)
1206 sigset_t saved_mask, new_block;
1208 int error, sig, timo, timevalid = 0;
1209 struct timespec rts, ets, ts;
1217 if (timeout != NULL) {
1218 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1220 getnanouptime(&rts);
1222 timespecadd(&ets, timeout);
1226 /* Some signals can not be waited for. */
1227 SIG_CANTMASK(waitset);
1230 saved_mask = td->td_sigmask;
1231 SIGSETNAND(td->td_sigmask, waitset);
1233 mtx_lock(&ps->ps_mtx);
1235 mtx_unlock(&ps->ps_mtx);
1236 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1237 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1238 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1248 * POSIX says this must be checked after looking for pending
1251 if (timeout != NULL) {
1256 getnanouptime(&rts);
1257 if (timespeccmp(&rts, &ets, >=)) {
1262 timespecsub(&ts, &rts);
1263 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1269 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1271 if (timeout != NULL) {
1272 if (error == ERESTART) {
1273 /* Timeout can not be restarted. */
1275 } else if (error == EAGAIN) {
1276 /* We will calculate timeout by ourself. */
1282 new_block = saved_mask;
1283 SIGSETNAND(new_block, td->td_sigmask);
1284 td->td_sigmask = saved_mask;
1286 * Fewer signals can be delivered to us, reschedule signal
1289 if (p->p_numthreads != 1)
1290 reschedule_signals(p, new_block, 0);
1293 SDT_PROBE(proc, kernel, , signal__clear, sig, ksi, 0, 0, 0);
1295 if (ksi->ksi_code == SI_TIMER)
1296 itimer_accept(p, ksi->ksi_timerid, ksi);
1299 if (KTRPOINT(td, KTR_PSIG)) {
1302 mtx_lock(&ps->ps_mtx);
1303 action = ps->ps_sigact[_SIG_IDX(sig)];
1304 mtx_unlock(&ps->ps_mtx);
1305 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1315 #ifndef _SYS_SYSPROTO_H_
1316 struct sigpending_args {
1321 sys_sigpending(td, uap)
1323 struct sigpending_args *uap;
1325 struct proc *p = td->td_proc;
1329 pending = p->p_sigqueue.sq_signals;
1330 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1332 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1335 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1336 #ifndef _SYS_SYSPROTO_H_
1337 struct osigpending_args {
1342 osigpending(td, uap)
1344 struct osigpending_args *uap;
1346 struct proc *p = td->td_proc;
1350 pending = p->p_sigqueue.sq_signals;
1351 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1353 SIG2OSIG(pending, td->td_retval[0]);
1356 #endif /* COMPAT_43 */
1358 #if defined(COMPAT_43)
1360 * Generalized interface signal handler, 4.3-compatible.
1362 #ifndef _SYS_SYSPROTO_H_
1363 struct osigvec_args {
1373 register struct osigvec_args *uap;
1376 struct sigaction nsa, osa;
1377 register struct sigaction *nsap, *osap;
1380 if (uap->signum <= 0 || uap->signum >= ONSIG)
1382 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1383 osap = (uap->osv != NULL) ? &osa : NULL;
1385 error = copyin(uap->nsv, &vec, sizeof(vec));
1388 nsap->sa_handler = vec.sv_handler;
1389 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1390 nsap->sa_flags = vec.sv_flags;
1391 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1393 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1394 if (osap && !error) {
1395 vec.sv_handler = osap->sa_handler;
1396 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1397 vec.sv_flags = osap->sa_flags;
1398 vec.sv_flags &= ~SA_NOCLDWAIT;
1399 vec.sv_flags ^= SA_RESTART;
1400 error = copyout(&vec, uap->osv, sizeof(vec));
1405 #ifndef _SYS_SYSPROTO_H_
1406 struct osigblock_args {
1412 register struct thread *td;
1413 struct osigblock_args *uap;
1417 OSIG2SIG(uap->mask, set);
1418 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1419 SIG2OSIG(oset, td->td_retval[0]);
1423 #ifndef _SYS_SYSPROTO_H_
1424 struct osigsetmask_args {
1429 osigsetmask(td, uap)
1431 struct osigsetmask_args *uap;
1435 OSIG2SIG(uap->mask, set);
1436 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1437 SIG2OSIG(oset, td->td_retval[0]);
1440 #endif /* COMPAT_43 */
1443 * Suspend calling thread until signal, providing mask to be set in the
1446 #ifndef _SYS_SYSPROTO_H_
1447 struct sigsuspend_args {
1448 const sigset_t *sigmask;
1453 sys_sigsuspend(td, uap)
1455 struct sigsuspend_args *uap;
1460 error = copyin(uap->sigmask, &mask, sizeof(mask));
1463 return (kern_sigsuspend(td, mask));
1467 kern_sigsuspend(struct thread *td, sigset_t mask)
1469 struct proc *p = td->td_proc;
1473 * When returning from sigsuspend, we want
1474 * the old mask to be restored after the
1475 * signal handler has finished. Thus, we
1476 * save it here and mark the sigacts structure
1480 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1481 SIGPROCMASK_PROC_LOCKED);
1482 td->td_pflags |= TDP_OLDMASK;
1485 * Process signals now. Otherwise, we can get spurious wakeup
1486 * due to signal entered process queue, but delivered to other
1487 * thread. But sigsuspend should return only on signal
1490 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1491 for (has_sig = 0; !has_sig;) {
1492 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1495 thread_suspend_check(0);
1496 mtx_lock(&p->p_sigacts->ps_mtx);
1497 while ((sig = cursig(td)) != 0)
1498 has_sig += postsig(sig);
1499 mtx_unlock(&p->p_sigacts->ps_mtx);
1502 td->td_errno = EINTR;
1503 td->td_pflags |= TDP_NERRNO;
1504 return (EJUSTRETURN);
1507 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1509 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1510 * convention: libc stub passes mask, not pointer, to save a copyin.
1512 #ifndef _SYS_SYSPROTO_H_
1513 struct osigsuspend_args {
1519 osigsuspend(td, uap)
1521 struct osigsuspend_args *uap;
1525 OSIG2SIG(uap->mask, mask);
1526 return (kern_sigsuspend(td, mask));
1528 #endif /* COMPAT_43 */
1530 #if defined(COMPAT_43)
1531 #ifndef _SYS_SYSPROTO_H_
1532 struct osigstack_args {
1533 struct sigstack *nss;
1534 struct sigstack *oss;
1541 register struct osigstack_args *uap;
1543 struct sigstack nss, oss;
1546 if (uap->nss != NULL) {
1547 error = copyin(uap->nss, &nss, sizeof(nss));
1551 oss.ss_sp = td->td_sigstk.ss_sp;
1552 oss.ss_onstack = sigonstack(cpu_getstack(td));
1553 if (uap->nss != NULL) {
1554 td->td_sigstk.ss_sp = nss.ss_sp;
1555 td->td_sigstk.ss_size = 0;
1556 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1557 td->td_pflags |= TDP_ALTSTACK;
1559 if (uap->oss != NULL)
1560 error = copyout(&oss, uap->oss, sizeof(oss));
1564 #endif /* COMPAT_43 */
1566 #ifndef _SYS_SYSPROTO_H_
1567 struct sigaltstack_args {
1574 sys_sigaltstack(td, uap)
1576 register struct sigaltstack_args *uap;
1581 if (uap->ss != NULL) {
1582 error = copyin(uap->ss, &ss, sizeof(ss));
1586 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1587 (uap->oss != NULL) ? &oss : NULL);
1590 if (uap->oss != NULL)
1591 error = copyout(&oss, uap->oss, sizeof(stack_t));
1596 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1598 struct proc *p = td->td_proc;
1601 oonstack = sigonstack(cpu_getstack(td));
1604 *oss = td->td_sigstk;
1605 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1606 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1612 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1614 if (!(ss->ss_flags & SS_DISABLE)) {
1615 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1618 td->td_sigstk = *ss;
1619 td->td_pflags |= TDP_ALTSTACK;
1621 td->td_pflags &= ~TDP_ALTSTACK;
1628 * Common code for kill process group/broadcast kill.
1629 * cp is calling process.
1632 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1644 sx_slock(&allproc_lock);
1645 FOREACH_PROC_IN_SYSTEM(p) {
1647 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1648 p == td->td_proc || p->p_state == PRS_NEW) {
1652 err = p_cansignal(td, p, sig);
1655 pksignal(p, sig, ksi);
1658 else if (ret == ESRCH)
1662 sx_sunlock(&allproc_lock);
1664 sx_slock(&proctree_lock);
1667 * zero pgid means send to my process group.
1669 pgrp = td->td_proc->p_pgrp;
1672 pgrp = pgfind(pgid);
1674 sx_sunlock(&proctree_lock);
1678 sx_sunlock(&proctree_lock);
1679 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1681 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1682 p->p_state == PRS_NEW) {
1686 err = p_cansignal(td, p, sig);
1689 pksignal(p, sig, ksi);
1692 else if (ret == ESRCH)
1701 #ifndef _SYS_SYSPROTO_H_
1709 sys_kill(struct thread *td, struct kill_args *uap)
1716 * A process in capability mode can send signals only to himself.
1717 * The main rationale behind this is that abort(3) is implemented as
1718 * kill(getpid(), SIGABRT).
1720 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1723 AUDIT_ARG_SIGNUM(uap->signum);
1724 AUDIT_ARG_PID(uap->pid);
1725 if ((u_int)uap->signum > _SIG_MAXSIG)
1728 ksiginfo_init(&ksi);
1729 ksi.ksi_signo = uap->signum;
1730 ksi.ksi_code = SI_USER;
1731 ksi.ksi_pid = td->td_proc->p_pid;
1732 ksi.ksi_uid = td->td_ucred->cr_ruid;
1735 /* kill single process */
1736 if ((p = pfind(uap->pid)) == NULL) {
1737 if ((p = zpfind(uap->pid)) == NULL)
1740 AUDIT_ARG_PROCESS(p);
1741 error = p_cansignal(td, p, uap->signum);
1742 if (error == 0 && uap->signum)
1743 pksignal(p, uap->signum, &ksi);
1748 case -1: /* broadcast signal */
1749 return (killpg1(td, uap->signum, 0, 1, &ksi));
1750 case 0: /* signal own process group */
1751 return (killpg1(td, uap->signum, 0, 0, &ksi));
1752 default: /* negative explicit process group */
1753 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1761 struct pdkill_args *uap;
1765 cap_rights_t rights;
1768 AUDIT_ARG_SIGNUM(uap->signum);
1769 AUDIT_ARG_FD(uap->fd);
1770 if ((u_int)uap->signum > _SIG_MAXSIG)
1773 error = procdesc_find(td, uap->fd,
1774 cap_rights_init(&rights, CAP_PDKILL), &p);
1777 AUDIT_ARG_PROCESS(p);
1778 error = p_cansignal(td, p, uap->signum);
1779 if (error == 0 && uap->signum)
1780 kern_psignal(p, uap->signum);
1788 #if defined(COMPAT_43)
1789 #ifndef _SYS_SYSPROTO_H_
1790 struct okillpg_args {
1797 okillpg(struct thread *td, struct okillpg_args *uap)
1801 AUDIT_ARG_SIGNUM(uap->signum);
1802 AUDIT_ARG_PID(uap->pgid);
1803 if ((u_int)uap->signum > _SIG_MAXSIG)
1806 ksiginfo_init(&ksi);
1807 ksi.ksi_signo = uap->signum;
1808 ksi.ksi_code = SI_USER;
1809 ksi.ksi_pid = td->td_proc->p_pid;
1810 ksi.ksi_uid = td->td_ucred->cr_ruid;
1811 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1813 #endif /* COMPAT_43 */
1815 #ifndef _SYS_SYSPROTO_H_
1816 struct sigqueue_args {
1819 /* union sigval */ void *value;
1823 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1829 if ((u_int)uap->signum > _SIG_MAXSIG)
1833 * Specification says sigqueue can only send signal to
1839 if ((p = pfind(uap->pid)) == NULL) {
1840 if ((p = zpfind(uap->pid)) == NULL)
1843 error = p_cansignal(td, p, uap->signum);
1844 if (error == 0 && uap->signum != 0) {
1845 ksiginfo_init(&ksi);
1846 ksi.ksi_flags = KSI_SIGQ;
1847 ksi.ksi_signo = uap->signum;
1848 ksi.ksi_code = SI_QUEUE;
1849 ksi.ksi_pid = td->td_proc->p_pid;
1850 ksi.ksi_uid = td->td_ucred->cr_ruid;
1851 ksi.ksi_value.sival_ptr = uap->value;
1852 error = pksignal(p, ksi.ksi_signo, &ksi);
1859 * Send a signal to a process group.
1862 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1867 sx_slock(&proctree_lock);
1868 pgrp = pgfind(pgid);
1869 sx_sunlock(&proctree_lock);
1871 pgsignal(pgrp, sig, 0, ksi);
1878 * Send a signal to a process group. If checktty is 1,
1879 * limit to members which have a controlling terminal.
1882 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1887 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1888 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1890 if (p->p_state == PRS_NORMAL &&
1891 (checkctty == 0 || p->p_flag & P_CONTROLT))
1892 pksignal(p, sig, ksi);
1900 * Recalculate the signal mask and reset the signal disposition after
1901 * usermode frame for delivery is formed. Should be called after
1902 * mach-specific routine, because sysent->sv_sendsig() needs correct
1903 * ps_siginfo and signal mask.
1906 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1910 mtx_assert(&ps->ps_mtx, MA_OWNED);
1911 td->td_ru.ru_nsignals++;
1912 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1913 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1914 SIGADDSET(mask, sig);
1915 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1916 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1917 if (SIGISMEMBER(ps->ps_sigreset, sig))
1923 * Send a signal caused by a trap to the current thread. If it will be
1924 * caught immediately, deliver it with correct code. Otherwise, post it
1928 trapsignal(struct thread *td, ksiginfo_t *ksi)
1936 sig = ksi->ksi_signo;
1937 code = ksi->ksi_code;
1938 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1942 mtx_lock(&ps->ps_mtx);
1943 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1944 !SIGISMEMBER(td->td_sigmask, sig)) {
1946 if (KTRPOINT(curthread, KTR_PSIG))
1947 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1948 &td->td_sigmask, code);
1950 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1951 ksi, &td->td_sigmask);
1952 postsig_done(sig, td, ps);
1953 mtx_unlock(&ps->ps_mtx);
1956 * Avoid a possible infinite loop if the thread
1957 * masking the signal or process is ignoring the
1960 if (kern_forcesigexit &&
1961 (SIGISMEMBER(td->td_sigmask, sig) ||
1962 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1963 SIGDELSET(td->td_sigmask, sig);
1964 SIGDELSET(ps->ps_sigcatch, sig);
1965 SIGDELSET(ps->ps_sigignore, sig);
1966 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1968 mtx_unlock(&ps->ps_mtx);
1969 p->p_code = code; /* XXX for core dump/debugger */
1970 p->p_sig = sig; /* XXX to verify code */
1971 tdsendsignal(p, td, sig, ksi);
1976 static struct thread *
1977 sigtd(struct proc *p, int sig, int prop)
1979 struct thread *td, *signal_td;
1981 PROC_LOCK_ASSERT(p, MA_OWNED);
1984 * Check if current thread can handle the signal without
1985 * switching context to another thread.
1987 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1990 FOREACH_THREAD_IN_PROC(p, td) {
1991 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1996 if (signal_td == NULL)
1997 signal_td = FIRST_THREAD_IN_PROC(p);
2002 * Send the signal to the process. If the signal has an action, the action
2003 * is usually performed by the target process rather than the caller; we add
2004 * the signal to the set of pending signals for the process.
2007 * o When a stop signal is sent to a sleeping process that takes the
2008 * default action, the process is stopped without awakening it.
2009 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2010 * regardless of the signal action (eg, blocked or ignored).
2012 * Other ignored signals are discarded immediately.
2014 * NB: This function may be entered from the debugger via the "kill" DDB
2015 * command. There is little that can be done to mitigate the possibly messy
2016 * side effects of this unwise possibility.
2019 kern_psignal(struct proc *p, int sig)
2023 ksiginfo_init(&ksi);
2024 ksi.ksi_signo = sig;
2025 ksi.ksi_code = SI_KERNEL;
2026 (void) tdsendsignal(p, NULL, sig, &ksi);
2030 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2033 return (tdsendsignal(p, NULL, sig, ksi));
2036 /* Utility function for finding a thread to send signal event to. */
2038 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2042 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2043 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2055 tdsignal(struct thread *td, int sig)
2059 ksiginfo_init(&ksi);
2060 ksi.ksi_signo = sig;
2061 ksi.ksi_code = SI_KERNEL;
2062 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2066 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2069 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2073 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2076 sigqueue_t *sigqueue;
2083 MPASS(td == NULL || p == td->td_proc);
2084 PROC_LOCK_ASSERT(p, MA_OWNED);
2086 if (!_SIG_VALID(sig))
2087 panic("%s(): invalid signal %d", __func__, sig);
2089 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2092 * IEEE Std 1003.1-2001: return success when killing a zombie.
2094 if (p->p_state == PRS_ZOMBIE) {
2095 if (ksi && (ksi->ksi_flags & KSI_INS))
2096 ksiginfo_tryfree(ksi);
2101 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2102 prop = sigprop(sig);
2105 td = sigtd(p, sig, prop);
2106 sigqueue = &p->p_sigqueue;
2108 sigqueue = &td->td_sigqueue;
2110 SDT_PROBE(proc, kernel, , signal__send, td, p, sig, 0, 0 );
2113 * If the signal is being ignored,
2114 * then we forget about it immediately.
2115 * (Note: we don't set SIGCONT in ps_sigignore,
2116 * and if it is set to SIG_IGN,
2117 * action will be SIG_DFL here.)
2119 mtx_lock(&ps->ps_mtx);
2120 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2121 SDT_PROBE(proc, kernel, , signal__discard, td, p, sig, 0, 0 );
2123 mtx_unlock(&ps->ps_mtx);
2124 if (ksi && (ksi->ksi_flags & KSI_INS))
2125 ksiginfo_tryfree(ksi);
2128 if (SIGISMEMBER(td->td_sigmask, sig))
2130 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2134 if (SIGISMEMBER(ps->ps_sigintr, sig))
2138 mtx_unlock(&ps->ps_mtx);
2141 sigqueue_delete_stopmask_proc(p);
2142 else if (prop & SA_STOP) {
2144 * If sending a tty stop signal to a member of an orphaned
2145 * process group, discard the signal here if the action
2146 * is default; don't stop the process below if sleeping,
2147 * and don't clear any pending SIGCONT.
2149 if ((prop & SA_TTYSTOP) &&
2150 (p->p_pgrp->pg_jobc == 0) &&
2151 (action == SIG_DFL)) {
2152 if (ksi && (ksi->ksi_flags & KSI_INS))
2153 ksiginfo_tryfree(ksi);
2156 sigqueue_delete_proc(p, SIGCONT);
2157 if (p->p_flag & P_CONTINUED) {
2158 p->p_flag &= ~P_CONTINUED;
2159 PROC_LOCK(p->p_pptr);
2160 sigqueue_take(p->p_ksi);
2161 PROC_UNLOCK(p->p_pptr);
2165 ret = sigqueue_add(sigqueue, sig, ksi);
2170 * Defer further processing for signals which are held,
2171 * except that stopped processes must be continued by SIGCONT.
2173 if (action == SIG_HOLD &&
2174 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2177 * SIGKILL: Remove procfs STOPEVENTs.
2179 if (sig == SIGKILL) {
2180 /* from procfs_ioctl.c: PIOCBIC */
2182 /* from procfs_ioctl.c: PIOCCONT */
2187 * Some signals have a process-wide effect and a per-thread
2188 * component. Most processing occurs when the process next
2189 * tries to cross the user boundary, however there are some
2190 * times when processing needs to be done immediately, such as
2191 * waking up threads so that they can cross the user boundary.
2192 * We try to do the per-process part here.
2194 if (P_SHOULDSTOP(p)) {
2195 KASSERT(!(p->p_flag & P_WEXIT),
2196 ("signal to stopped but exiting process"));
2197 if (sig == SIGKILL) {
2199 * If traced process is already stopped,
2200 * then no further action is necessary.
2202 if (p->p_flag & P_TRACED)
2205 * SIGKILL sets process running.
2206 * It will die elsewhere.
2207 * All threads must be restarted.
2209 p->p_flag &= ~P_STOPPED_SIG;
2213 if (prop & SA_CONT) {
2215 * If traced process is already stopped,
2216 * then no further action is necessary.
2218 if (p->p_flag & P_TRACED)
2221 * If SIGCONT is default (or ignored), we continue the
2222 * process but don't leave the signal in sigqueue as
2223 * it has no further action. If SIGCONT is held, we
2224 * continue the process and leave the signal in
2225 * sigqueue. If the process catches SIGCONT, let it
2226 * handle the signal itself. If it isn't waiting on
2227 * an event, it goes back to run state.
2228 * Otherwise, process goes back to sleep state.
2230 p->p_flag &= ~P_STOPPED_SIG;
2232 if (p->p_numthreads == p->p_suspcount) {
2234 p->p_flag |= P_CONTINUED;
2235 p->p_xstat = SIGCONT;
2236 PROC_LOCK(p->p_pptr);
2237 childproc_continued(p);
2238 PROC_UNLOCK(p->p_pptr);
2241 if (action == SIG_DFL) {
2242 thread_unsuspend(p);
2244 sigqueue_delete(sigqueue, sig);
2247 if (action == SIG_CATCH) {
2249 * The process wants to catch it so it needs
2250 * to run at least one thread, but which one?
2256 * The signal is not ignored or caught.
2258 thread_unsuspend(p);
2263 if (prop & SA_STOP) {
2265 * If traced process is already stopped,
2266 * then no further action is necessary.
2268 if (p->p_flag & P_TRACED)
2271 * Already stopped, don't need to stop again
2272 * (If we did the shell could get confused).
2273 * Just make sure the signal STOP bit set.
2275 p->p_flag |= P_STOPPED_SIG;
2276 sigqueue_delete(sigqueue, sig);
2281 * All other kinds of signals:
2282 * If a thread is sleeping interruptibly, simulate a
2283 * wakeup so that when it is continued it will be made
2284 * runnable and can look at the signal. However, don't make
2285 * the PROCESS runnable, leave it stopped.
2286 * It may run a bit until it hits a thread_suspend_check().
2291 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2292 wakeup_swapper = sleepq_abort(td, intrval);
2299 * Mutexes are short lived. Threads waiting on them will
2300 * hit thread_suspend_check() soon.
2302 } else if (p->p_state == PRS_NORMAL) {
2303 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2304 tdsigwakeup(td, sig, action, intrval);
2308 MPASS(action == SIG_DFL);
2310 if (prop & SA_STOP) {
2311 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2313 p->p_flag |= P_STOPPED_SIG;
2316 sig_suspend_threads(td, p, 1);
2317 if (p->p_numthreads == p->p_suspcount) {
2319 * only thread sending signal to another
2320 * process can reach here, if thread is sending
2321 * signal to its process, because thread does
2322 * not suspend itself here, p_numthreads
2323 * should never be equal to p_suspcount.
2327 sigqueue_delete_proc(p, p->p_xstat);
2333 /* Not in "NORMAL" state. discard the signal. */
2334 sigqueue_delete(sigqueue, sig);
2339 * The process is not stopped so we need to apply the signal to all the
2343 tdsigwakeup(td, sig, action, intrval);
2345 thread_unsuspend(p);
2348 /* If we jump here, proc slock should not be owned. */
2349 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2354 * The force of a signal has been directed against a single
2355 * thread. We need to see what we can do about knocking it
2356 * out of any sleep it may be in etc.
2359 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2361 struct proc *p = td->td_proc;
2366 PROC_LOCK_ASSERT(p, MA_OWNED);
2367 prop = sigprop(sig);
2372 * Bring the priority of a thread up if we want it to get
2373 * killed in this lifetime.
2375 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2376 sched_prio(td, PUSER);
2377 if (TD_ON_SLEEPQ(td)) {
2379 * If thread is sleeping uninterruptibly
2380 * we can't interrupt the sleep... the signal will
2381 * be noticed when the process returns through
2382 * trap() or syscall().
2384 if ((td->td_flags & TDF_SINTR) == 0)
2387 * If SIGCONT is default (or ignored) and process is
2388 * asleep, we are finished; the process should not
2391 if ((prop & SA_CONT) && action == SIG_DFL) {
2394 sigqueue_delete(&p->p_sigqueue, sig);
2396 * It may be on either list in this state.
2397 * Remove from both for now.
2399 sigqueue_delete(&td->td_sigqueue, sig);
2404 * Don't awaken a sleeping thread for SIGSTOP if the
2405 * STOP signal is deferred.
2407 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2411 * Give low priority threads a better chance to run.
2413 if (td->td_priority > PUSER)
2414 sched_prio(td, PUSER);
2416 wakeup_swapper = sleepq_abort(td, intrval);
2419 * Other states do nothing with the signal immediately,
2420 * other than kicking ourselves if we are running.
2421 * It will either never be noticed, or noticed very soon.
2424 if (TD_IS_RUNNING(td) && td != curthread)
2436 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2440 PROC_LOCK_ASSERT(p, MA_OWNED);
2441 PROC_SLOCK_ASSERT(p, MA_OWNED);
2443 FOREACH_THREAD_IN_PROC(p, td2) {
2445 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2446 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2447 (td2->td_flags & TDF_SINTR)) {
2448 if (td2->td_flags & TDF_SBDRY) {
2450 * Once a thread is asleep with
2451 * TDF_SBDRY set, it should never
2452 * become suspended due to this check.
2454 KASSERT(!TD_IS_SUSPENDED(td2),
2455 ("thread with deferred stops suspended"));
2456 } else if (!TD_IS_SUSPENDED(td2)) {
2457 thread_suspend_one(td2);
2459 } else if (!TD_IS_SUSPENDED(td2)) {
2460 if (sending || td != td2)
2461 td2->td_flags |= TDF_ASTPENDING;
2463 if (TD_IS_RUNNING(td2) && td2 != td)
2464 forward_signal(td2);
2472 ptracestop(struct thread *td, int sig)
2474 struct proc *p = td->td_proc;
2476 PROC_LOCK_ASSERT(p, MA_OWNED);
2477 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2478 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2479 &p->p_mtx.lock_object, "Stopping for traced signal");
2481 td->td_dbgflags |= TDB_XSIG;
2484 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2485 if (p->p_flag & P_SINGLE_EXIT) {
2486 td->td_dbgflags &= ~TDB_XSIG;
2491 * Just make wait() to work, the last stopped thread
2496 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2497 sig_suspend_threads(td, p, 0);
2498 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2499 td->td_dbgflags &= ~TDB_STOPATFORK;
2500 cv_broadcast(&p->p_dbgwait);
2503 thread_suspend_switch(td, p);
2504 if (p->p_xthread == td)
2505 p->p_xthread = NULL;
2506 if (!(p->p_flag & P_TRACED))
2508 if (td->td_dbgflags & TDB_SUSPEND) {
2509 if (p->p_flag & P_SINGLE_EXIT)
2515 return (td->td_xsig);
2519 reschedule_signals(struct proc *p, sigset_t block, int flags)
2525 PROC_LOCK_ASSERT(p, MA_OWNED);
2527 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2528 MA_OWNED : MA_NOTOWNED);
2529 if (SIGISEMPTY(p->p_siglist))
2531 SIGSETAND(block, p->p_siglist);
2532 while ((sig = sig_ffs(&block)) != 0) {
2533 SIGDELSET(block, sig);
2534 td = sigtd(p, sig, 0);
2536 if (!(flags & SIGPROCMASK_PS_LOCKED))
2537 mtx_lock(&ps->ps_mtx);
2538 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2539 tdsigwakeup(td, sig, SIG_CATCH,
2540 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2542 if (!(flags & SIGPROCMASK_PS_LOCKED))
2543 mtx_unlock(&ps->ps_mtx);
2548 tdsigcleanup(struct thread *td)
2554 PROC_LOCK_ASSERT(p, MA_OWNED);
2556 sigqueue_flush(&td->td_sigqueue);
2557 if (p->p_numthreads == 1)
2561 * Since we cannot handle signals, notify signal post code
2562 * about this by filling the sigmask.
2564 * Also, if needed, wake up thread(s) that do not block the
2565 * same signals as the exiting thread, since the thread might
2566 * have been selected for delivery and woken up.
2568 SIGFILLSET(unblocked);
2569 SIGSETNAND(unblocked, td->td_sigmask);
2570 SIGFILLSET(td->td_sigmask);
2571 reschedule_signals(p, unblocked, 0);
2576 * Defer the delivery of SIGSTOP for the current thread. Returns true
2577 * if stops were deferred and false if they were already deferred.
2585 if (td->td_flags & TDF_SBDRY)
2588 td->td_flags |= TDF_SBDRY;
2594 * Permit the delivery of SIGSTOP for the current thread. This does
2595 * not immediately suspend if a stop was posted. Instead, the thread
2596 * will suspend either via ast() or a subsequent interruptible sleep.
2605 td->td_flags &= ~TDF_SBDRY;
2610 * If the current process has received a signal (should be caught or cause
2611 * termination, should interrupt current syscall), return the signal number.
2612 * Stop signals with default action are processed immediately, then cleared;
2613 * they aren't returned. This is checked after each entry to the system for
2614 * a syscall or trap (though this can usually be done without calling issignal
2615 * by checking the pending signal masks in cursig.) The normal call
2618 * while (sig = cursig(curthread))
2622 issignal(struct thread *td)
2626 struct sigqueue *queue;
2627 sigset_t sigpending;
2628 int sig, prop, newsig;
2632 mtx_assert(&ps->ps_mtx, MA_OWNED);
2633 PROC_LOCK_ASSERT(p, MA_OWNED);
2635 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2637 sigpending = td->td_sigqueue.sq_signals;
2638 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2639 SIGSETNAND(sigpending, td->td_sigmask);
2641 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2642 SIG_STOPSIGMASK(sigpending);
2643 if (SIGISEMPTY(sigpending)) /* no signal to send */
2645 sig = sig_ffs(&sigpending);
2647 if (p->p_stops & S_SIG) {
2648 mtx_unlock(&ps->ps_mtx);
2649 stopevent(p, S_SIG, sig);
2650 mtx_lock(&ps->ps_mtx);
2654 * We should see pending but ignored signals
2655 * only if P_TRACED was on when they were posted.
2657 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2658 sigqueue_delete(&td->td_sigqueue, sig);
2659 sigqueue_delete(&p->p_sigqueue, sig);
2662 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) {
2664 * If traced, always stop.
2665 * Remove old signal from queue before the stop.
2666 * XXX shrug off debugger, it causes siginfo to
2669 queue = &td->td_sigqueue;
2670 td->td_dbgksi.ksi_signo = 0;
2671 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2672 queue = &p->p_sigqueue;
2673 sigqueue_get(queue, sig, &td->td_dbgksi);
2676 mtx_unlock(&ps->ps_mtx);
2677 newsig = ptracestop(td, sig);
2678 mtx_lock(&ps->ps_mtx);
2680 if (sig != newsig) {
2683 * If parent wants us to take the signal,
2684 * then it will leave it in p->p_xstat;
2685 * otherwise we just look for signals again.
2692 * Put the new signal into td_sigqueue. If the
2693 * signal is being masked, look for other
2696 sigqueue_add(queue, sig, NULL);
2697 if (SIGISMEMBER(td->td_sigmask, sig))
2701 if (td->td_dbgksi.ksi_signo != 0) {
2702 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2703 if (sigqueue_add(&td->td_sigqueue, sig,
2704 &td->td_dbgksi) != 0)
2705 td->td_dbgksi.ksi_signo = 0;
2707 if (td->td_dbgksi.ksi_signo == 0)
2708 sigqueue_add(&td->td_sigqueue, sig,
2713 * If the traced bit got turned off, go back up
2714 * to the top to rescan signals. This ensures
2715 * that p_sig* and p_sigact are consistent.
2717 if ((p->p_flag & P_TRACED) == 0)
2721 prop = sigprop(sig);
2724 * Decide whether the signal should be returned.
2725 * Return the signal's number, or fall through
2726 * to clear it from the pending mask.
2728 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2730 case (intptr_t)SIG_DFL:
2732 * Don't take default actions on system processes.
2734 if (p->p_pid <= 1) {
2737 * Are you sure you want to ignore SIGSEGV
2740 printf("Process (pid %lu) got signal %d\n",
2741 (u_long)p->p_pid, sig);
2743 break; /* == ignore */
2746 * If there is a pending stop signal to process
2747 * with default action, stop here,
2748 * then clear the signal. However,
2749 * if process is member of an orphaned
2750 * process group, ignore tty stop signals.
2752 if (prop & SA_STOP) {
2753 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2754 (p->p_pgrp->pg_jobc == 0 &&
2756 break; /* == ignore */
2757 mtx_unlock(&ps->ps_mtx);
2758 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2759 &p->p_mtx.lock_object, "Catching SIGSTOP");
2760 p->p_flag |= P_STOPPED_SIG;
2763 sig_suspend_threads(td, p, 0);
2764 thread_suspend_switch(td, p);
2766 mtx_lock(&ps->ps_mtx);
2768 } else if (prop & SA_IGNORE) {
2770 * Except for SIGCONT, shouldn't get here.
2771 * Default action is to ignore; drop it.
2773 break; /* == ignore */
2778 case (intptr_t)SIG_IGN:
2780 * Masking above should prevent us ever trying
2781 * to take action on an ignored signal other
2782 * than SIGCONT, unless process is traced.
2784 if ((prop & SA_CONT) == 0 &&
2785 (p->p_flag & P_TRACED) == 0)
2786 printf("issignal\n");
2787 break; /* == ignore */
2791 * This signal has an action, let
2792 * postsig() process it.
2796 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2797 sigqueue_delete(&p->p_sigqueue, sig);
2803 thread_stopped(struct proc *p)
2807 PROC_LOCK_ASSERT(p, MA_OWNED);
2808 PROC_SLOCK_ASSERT(p, MA_OWNED);
2812 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2814 p->p_flag &= ~P_WAITED;
2815 PROC_LOCK(p->p_pptr);
2816 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2817 CLD_TRAPPED : CLD_STOPPED);
2818 PROC_UNLOCK(p->p_pptr);
2824 * Take the action for the specified signal
2825 * from the current set of pending signals.
2831 struct thread *td = curthread;
2832 register struct proc *p = td->td_proc;
2836 sigset_t returnmask;
2838 KASSERT(sig != 0, ("postsig"));
2840 PROC_LOCK_ASSERT(p, MA_OWNED);
2842 mtx_assert(&ps->ps_mtx, MA_OWNED);
2843 ksiginfo_init(&ksi);
2844 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2845 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2847 ksi.ksi_signo = sig;
2848 if (ksi.ksi_code == SI_TIMER)
2849 itimer_accept(p, ksi.ksi_timerid, &ksi);
2850 action = ps->ps_sigact[_SIG_IDX(sig)];
2852 if (KTRPOINT(td, KTR_PSIG))
2853 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2854 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2856 if (p->p_stops & S_SIG) {
2857 mtx_unlock(&ps->ps_mtx);
2858 stopevent(p, S_SIG, sig);
2859 mtx_lock(&ps->ps_mtx);
2862 if (action == SIG_DFL) {
2864 * Default action, where the default is to kill
2865 * the process. (Other cases were ignored above.)
2867 mtx_unlock(&ps->ps_mtx);
2872 * If we get here, the signal must be caught.
2874 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2875 ("postsig action"));
2877 * Set the new mask value and also defer further
2878 * occurrences of this signal.
2880 * Special case: user has done a sigsuspend. Here the
2881 * current mask is not of interest, but rather the
2882 * mask from before the sigsuspend is what we want
2883 * restored after the signal processing is completed.
2885 if (td->td_pflags & TDP_OLDMASK) {
2886 returnmask = td->td_oldsigmask;
2887 td->td_pflags &= ~TDP_OLDMASK;
2889 returnmask = td->td_sigmask;
2891 if (p->p_sig == sig) {
2895 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2896 postsig_done(sig, td, ps);
2902 * Kill the current process for stated reason.
2910 PROC_LOCK_ASSERT(p, MA_OWNED);
2911 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2913 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2914 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2915 p->p_flag |= P_WKILLED;
2916 kern_psignal(p, SIGKILL);
2920 * Force the current process to exit with the specified signal, dumping core
2921 * if appropriate. We bypass the normal tests for masked and caught signals,
2922 * allowing unrecoverable failures to terminate the process without changing
2923 * signal state. Mark the accounting record with the signal termination.
2924 * If dumping core, save the signal number for the debugger. Calls exit and
2932 struct proc *p = td->td_proc;
2934 PROC_LOCK_ASSERT(p, MA_OWNED);
2935 p->p_acflag |= AXSIG;
2937 * We must be single-threading to generate a core dump. This
2938 * ensures that the registers in the core file are up-to-date.
2939 * Also, the ELF dump handler assumes that the thread list doesn't
2940 * change out from under it.
2942 * XXX If another thread attempts to single-thread before us
2943 * (e.g. via fork()), we won't get a dump at all.
2945 if ((sigprop(sig) & SA_CORE) && thread_single(p, SINGLE_NO_EXIT) == 0) {
2948 * Log signals which would cause core dumps
2949 * (Log as LOG_INFO to appease those who don't want
2951 * XXX : Todo, as well as euid, write out ruid too
2952 * Note that coredump() drops proc lock.
2954 if (coredump(td) == 0)
2956 if (kern_logsigexit)
2958 "pid %d (%s), uid %d: exited on signal %d%s\n",
2959 p->p_pid, p->p_comm,
2960 td->td_ucred ? td->td_ucred->cr_uid : -1,
2962 sig & WCOREFLAG ? " (core dumped)" : "");
2965 exit1(td, W_EXITCODE(0, sig));
2970 * Send queued SIGCHLD to parent when child process's state
2974 sigparent(struct proc *p, int reason, int status)
2976 PROC_LOCK_ASSERT(p, MA_OWNED);
2977 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2979 if (p->p_ksi != NULL) {
2980 p->p_ksi->ksi_signo = SIGCHLD;
2981 p->p_ksi->ksi_code = reason;
2982 p->p_ksi->ksi_status = status;
2983 p->p_ksi->ksi_pid = p->p_pid;
2984 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2985 if (KSI_ONQ(p->p_ksi))
2988 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2992 childproc_jobstate(struct proc *p, int reason, int sig)
2996 PROC_LOCK_ASSERT(p, MA_OWNED);
2997 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3000 * Wake up parent sleeping in kern_wait(), also send
3001 * SIGCHLD to parent, but SIGCHLD does not guarantee
3002 * that parent will awake, because parent may masked
3005 p->p_pptr->p_flag |= P_STATCHILD;
3008 ps = p->p_pptr->p_sigacts;
3009 mtx_lock(&ps->ps_mtx);
3010 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3011 mtx_unlock(&ps->ps_mtx);
3012 sigparent(p, reason, sig);
3014 mtx_unlock(&ps->ps_mtx);
3018 childproc_stopped(struct proc *p, int reason)
3020 /* p_xstat is a plain signal number, not a full wait() status here. */
3021 childproc_jobstate(p, reason, p->p_xstat);
3025 childproc_continued(struct proc *p)
3027 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3031 childproc_exited(struct proc *p)
3034 int xstat = p->p_xstat; /* convert to int */
3037 if (WCOREDUMP(xstat))
3038 reason = CLD_DUMPED, status = WTERMSIG(xstat);
3039 else if (WIFSIGNALED(xstat))
3040 reason = CLD_KILLED, status = WTERMSIG(xstat);
3042 reason = CLD_EXITED, status = WEXITSTATUS(xstat);
3044 * XXX avoid calling wakeup(p->p_pptr), the work is
3047 sigparent(p, reason, status);
3051 * We only have 1 character for the core count in the format
3052 * string, so the range will be 0-9
3054 #define MAX_NUM_CORES 10
3055 static int num_cores = 5;
3058 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3063 new_val = num_cores;
3064 error = sysctl_handle_int(oidp, &new_val, 0, req);
3065 if (error != 0 || req->newptr == NULL)
3067 if (new_val > MAX_NUM_CORES)
3068 new_val = MAX_NUM_CORES;
3071 num_cores = new_val;
3074 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3075 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3077 #if defined(COMPRESS_USER_CORES)
3078 int compress_user_cores = 1;
3079 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
3080 &compress_user_cores, 0, "Compression of user corefiles");
3082 int compress_user_cores_gzlevel = -1; /* default level */
3083 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
3084 &compress_user_cores_gzlevel, -1, "Corefile gzip compression level");
3086 #define GZ_SUFFIX ".gz"
3087 #define GZ_SUFFIX_LEN 3
3090 static char corefilename[MAXPATHLEN] = {"%N.core"};
3091 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3092 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3093 sizeof(corefilename), "Process corefile name format string");
3096 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3097 * Expand the name described in corefilename, using name, uid, and pid
3098 * and open/create core file.
3099 * corefilename is a printf-like string, with three format specifiers:
3100 * %N name of process ("name")
3101 * %P process id (pid)
3103 * For example, "%N.core" is the default; they can be disabled completely
3104 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3105 * This is controlled by the sysctl variable kern.corefile (see above).
3108 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3109 int compress, struct vnode **vpp, char **namep)
3111 struct nameidata nd;
3114 char *hostname, *name;
3115 int indexpos, i, error, cmode, flags, oflags;
3118 format = corefilename;
3119 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3121 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3122 for (i = 0; format[i] != '\0'; i++) {
3123 switch (format[i]) {
3124 case '%': /* Format character */
3126 switch (format[i]) {
3128 sbuf_putc(&sb, '%');
3130 case 'H': /* hostname */
3131 if (hostname == NULL) {
3132 hostname = malloc(MAXHOSTNAMELEN,
3135 getcredhostname(td->td_ucred, hostname,
3137 sbuf_printf(&sb, "%s", hostname);
3139 case 'I': /* autoincrementing index */
3140 sbuf_printf(&sb, "0");
3141 indexpos = sbuf_len(&sb) - 1;
3143 case 'N': /* process name */
3144 sbuf_printf(&sb, "%s", comm);
3146 case 'P': /* process id */
3147 sbuf_printf(&sb, "%u", pid);
3149 case 'U': /* user id */
3150 sbuf_printf(&sb, "%u", uid);
3154 "Unknown format character %c in "
3155 "corename `%s'\n", format[i], format);
3160 sbuf_putc(&sb, format[i]);
3164 free(hostname, M_TEMP);
3165 #ifdef COMPRESS_USER_CORES
3167 sbuf_printf(&sb, GZ_SUFFIX);
3169 if (sbuf_error(&sb) != 0) {
3170 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3171 "long\n", (long)pid, comm, (u_long)uid);
3179 cmode = S_IRUSR | S_IWUSR;
3180 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3181 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3184 * If the core format has a %I in it, then we need to check
3185 * for existing corefiles before returning a name.
3186 * To do this we iterate over 0..num_cores to find a
3187 * non-existing core file name to use.
3189 if (indexpos != -1) {
3190 for (i = 0; i < num_cores; i++) {
3191 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3192 name[indexpos] = '0' + i;
3193 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3194 error = vn_open_cred(&nd, &flags, cmode, oflags,
3195 td->td_ucred, NULL);
3197 if (error == EEXIST)
3200 "pid %d (%s), uid (%u): Path `%s' failed "
3201 "on initial open test, error = %d\n",
3202 pid, comm, uid, name, error);
3208 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3209 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3210 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3214 audit_proc_coredump(td, name, error);
3219 NDFREE(&nd, NDF_ONLY_PNBUF);
3226 * Dump a process' core. The main routine does some
3227 * policy checking, and creates the name of the coredump;
3228 * then it passes on a vnode and a size limit to the process-specific
3229 * coredump routine if there is one; if there _is not_ one, it returns
3230 * ENOSYS; otherwise it returns the error from the process-specific routine.
3234 coredump(struct thread *td)
3236 struct proc *p = td->td_proc;
3237 struct ucred *cred = td->td_ucred;
3241 int error, error1, locked;
3243 char *name; /* name of corefile */
3247 #ifdef COMPRESS_USER_CORES
3248 compress = compress_user_cores;
3252 PROC_LOCK_ASSERT(p, MA_OWNED);
3253 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3254 _STOPEVENT(p, S_CORE, 0);
3256 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0)) {
3262 * Note that the bulk of limit checking is done after
3263 * the corefile is created. The exception is if the limit
3264 * for corefiles is 0, in which case we don't bother
3265 * creating the corefile at all. This layout means that
3266 * a corefile is truncated instead of not being created,
3267 * if it is larger than the limit.
3269 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3270 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3277 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress,
3282 /* Don't dump to non-regular files or files with links. */
3283 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3284 vattr.va_nlink != 1) {
3291 lf.l_whence = SEEK_SET;
3294 lf.l_type = F_WRLCK;
3295 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3297 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3298 lf.l_type = F_UNLCK;
3300 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3301 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3303 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3311 if (set_core_nodump_flag)
3312 vattr.va_flags = UF_NODUMP;
3313 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3314 VOP_SETATTR(vp, &vattr, cred);
3316 vn_finished_write(mp);
3318 p->p_acflag |= ACORE;
3321 if (p->p_sysent->sv_coredump != NULL) {
3322 error = p->p_sysent->sv_coredump(td, vp, limit,
3323 compress ? IMGACT_CORE_COMPRESS : 0);
3329 lf.l_type = F_UNLCK;
3330 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3333 error1 = vn_close(vp, FWRITE, cred, td);
3338 audit_proc_coredump(td, name, error);
3345 * Nonexistent system call-- signal process (may want to handle it). Flag
3346 * error in case process won't see signal immediately (blocked or ignored).
3348 #ifndef _SYS_SYSPROTO_H_
3357 struct nosys_args *args;
3359 struct proc *p = td->td_proc;
3362 tdsignal(td, SIGSYS);
3368 * Send a SIGIO or SIGURG signal to a process or process group using stored
3369 * credentials rather than those of the current process.
3372 pgsigio(sigiop, sig, checkctty)
3373 struct sigio **sigiop;
3377 struct sigio *sigio;
3379 ksiginfo_init(&ksi);
3380 ksi.ksi_signo = sig;
3381 ksi.ksi_code = SI_KERNEL;
3385 if (sigio == NULL) {
3389 if (sigio->sio_pgid > 0) {
3390 PROC_LOCK(sigio->sio_proc);
3391 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3392 kern_psignal(sigio->sio_proc, sig);
3393 PROC_UNLOCK(sigio->sio_proc);
3394 } else if (sigio->sio_pgid < 0) {
3397 PGRP_LOCK(sigio->sio_pgrp);
3398 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3400 if (p->p_state == PRS_NORMAL &&
3401 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3402 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3403 kern_psignal(p, sig);
3406 PGRP_UNLOCK(sigio->sio_pgrp);
3412 filt_sigattach(struct knote *kn)
3414 struct proc *p = curproc;
3416 kn->kn_ptr.p_proc = p;
3417 kn->kn_flags |= EV_CLEAR; /* automatically set */
3419 knlist_add(&p->p_klist, kn, 0);
3425 filt_sigdetach(struct knote *kn)
3427 struct proc *p = kn->kn_ptr.p_proc;
3429 knlist_remove(&p->p_klist, kn, 0);
3433 * signal knotes are shared with proc knotes, so we apply a mask to
3434 * the hint in order to differentiate them from process hints. This
3435 * could be avoided by using a signal-specific knote list, but probably
3436 * isn't worth the trouble.
3439 filt_signal(struct knote *kn, long hint)
3442 if (hint & NOTE_SIGNAL) {
3443 hint &= ~NOTE_SIGNAL;
3445 if (kn->kn_id == hint)
3448 return (kn->kn_data != 0);
3456 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3458 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3463 sigacts_free(struct sigacts *ps)
3466 if (refcount_release(&ps->ps_refcnt) == 0)
3468 mtx_destroy(&ps->ps_mtx);
3469 free(ps, M_SUBPROC);
3473 sigacts_hold(struct sigacts *ps)
3476 refcount_acquire(&ps->ps_refcnt);
3481 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3484 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3485 mtx_lock(&src->ps_mtx);
3486 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3487 mtx_unlock(&src->ps_mtx);
3491 sigacts_shared(struct sigacts *ps)
3494 return (ps->ps_refcnt > 1);