2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
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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.
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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));
636 kern_sigaction(td, sig, act, oact, flags)
639 struct sigaction *act, *oact;
643 struct proc *p = td->td_proc;
645 if (!_SIG_VALID(sig))
650 mtx_lock(&ps->ps_mtx);
652 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
654 if (SIGISMEMBER(ps->ps_sigonstack, sig))
655 oact->sa_flags |= SA_ONSTACK;
656 if (!SIGISMEMBER(ps->ps_sigintr, sig))
657 oact->sa_flags |= SA_RESTART;
658 if (SIGISMEMBER(ps->ps_sigreset, sig))
659 oact->sa_flags |= SA_RESETHAND;
660 if (SIGISMEMBER(ps->ps_signodefer, sig))
661 oact->sa_flags |= SA_NODEFER;
662 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
663 oact->sa_flags |= SA_SIGINFO;
665 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
667 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
668 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
669 oact->sa_flags |= SA_NOCLDSTOP;
670 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
671 oact->sa_flags |= SA_NOCLDWAIT;
674 if ((sig == SIGKILL || sig == SIGSTOP) &&
675 act->sa_handler != SIG_DFL) {
676 mtx_unlock(&ps->ps_mtx);
682 * Change setting atomically.
685 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
686 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
687 if (act->sa_flags & SA_SIGINFO) {
688 ps->ps_sigact[_SIG_IDX(sig)] =
689 (__sighandler_t *)act->sa_sigaction;
690 SIGADDSET(ps->ps_siginfo, sig);
692 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
693 SIGDELSET(ps->ps_siginfo, sig);
695 if (!(act->sa_flags & SA_RESTART))
696 SIGADDSET(ps->ps_sigintr, sig);
698 SIGDELSET(ps->ps_sigintr, sig);
699 if (act->sa_flags & SA_ONSTACK)
700 SIGADDSET(ps->ps_sigonstack, sig);
702 SIGDELSET(ps->ps_sigonstack, sig);
703 if (act->sa_flags & SA_RESETHAND)
704 SIGADDSET(ps->ps_sigreset, sig);
706 SIGDELSET(ps->ps_sigreset, sig);
707 if (act->sa_flags & SA_NODEFER)
708 SIGADDSET(ps->ps_signodefer, sig);
710 SIGDELSET(ps->ps_signodefer, sig);
711 if (sig == SIGCHLD) {
712 if (act->sa_flags & SA_NOCLDSTOP)
713 ps->ps_flag |= PS_NOCLDSTOP;
715 ps->ps_flag &= ~PS_NOCLDSTOP;
716 if (act->sa_flags & SA_NOCLDWAIT) {
718 * Paranoia: since SA_NOCLDWAIT is implemented
719 * by reparenting the dying child to PID 1 (and
720 * trust it to reap the zombie), PID 1 itself
721 * is forbidden to set SA_NOCLDWAIT.
724 ps->ps_flag &= ~PS_NOCLDWAIT;
726 ps->ps_flag |= PS_NOCLDWAIT;
728 ps->ps_flag &= ~PS_NOCLDWAIT;
729 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
730 ps->ps_flag |= PS_CLDSIGIGN;
732 ps->ps_flag &= ~PS_CLDSIGIGN;
735 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
736 * and for signals set to SIG_DFL where the default is to
737 * ignore. However, don't put SIGCONT in ps_sigignore, as we
738 * have to restart the process.
740 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
741 (sigprop(sig) & SA_IGNORE &&
742 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
743 /* never to be seen again */
744 sigqueue_delete_proc(p, sig);
746 /* easier in psignal */
747 SIGADDSET(ps->ps_sigignore, sig);
748 SIGDELSET(ps->ps_sigcatch, sig);
750 SIGDELSET(ps->ps_sigignore, sig);
751 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
752 SIGDELSET(ps->ps_sigcatch, sig);
754 SIGADDSET(ps->ps_sigcatch, sig);
756 #ifdef COMPAT_FREEBSD4
757 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
758 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
759 (flags & KSA_FREEBSD4) == 0)
760 SIGDELSET(ps->ps_freebsd4, sig);
762 SIGADDSET(ps->ps_freebsd4, sig);
765 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
766 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
767 (flags & KSA_OSIGSET) == 0)
768 SIGDELSET(ps->ps_osigset, sig);
770 SIGADDSET(ps->ps_osigset, sig);
773 mtx_unlock(&ps->ps_mtx);
778 #ifndef _SYS_SYSPROTO_H_
779 struct sigaction_args {
781 struct sigaction *act;
782 struct sigaction *oact;
786 sys_sigaction(td, uap)
788 register struct sigaction_args *uap;
790 struct sigaction act, oact;
791 register struct sigaction *actp, *oactp;
794 actp = (uap->act != NULL) ? &act : NULL;
795 oactp = (uap->oact != NULL) ? &oact : NULL;
797 error = copyin(uap->act, actp, sizeof(act));
801 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
803 error = copyout(oactp, uap->oact, sizeof(oact));
807 #ifdef COMPAT_FREEBSD4
808 #ifndef _SYS_SYSPROTO_H_
809 struct freebsd4_sigaction_args {
811 struct sigaction *act;
812 struct sigaction *oact;
816 freebsd4_sigaction(td, uap)
818 register struct freebsd4_sigaction_args *uap;
820 struct sigaction act, oact;
821 register struct sigaction *actp, *oactp;
825 actp = (uap->act != NULL) ? &act : NULL;
826 oactp = (uap->oact != NULL) ? &oact : NULL;
828 error = copyin(uap->act, actp, sizeof(act));
832 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
834 error = copyout(oactp, uap->oact, sizeof(oact));
837 #endif /* COMAPT_FREEBSD4 */
839 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
840 #ifndef _SYS_SYSPROTO_H_
841 struct osigaction_args {
843 struct osigaction *nsa;
844 struct osigaction *osa;
850 register struct osigaction_args *uap;
852 struct osigaction sa;
853 struct sigaction nsa, osa;
854 register struct sigaction *nsap, *osap;
857 if (uap->signum <= 0 || uap->signum >= ONSIG)
860 nsap = (uap->nsa != NULL) ? &nsa : NULL;
861 osap = (uap->osa != NULL) ? &osa : NULL;
864 error = copyin(uap->nsa, &sa, sizeof(sa));
867 nsap->sa_handler = sa.sa_handler;
868 nsap->sa_flags = sa.sa_flags;
869 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
871 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
872 if (osap && !error) {
873 sa.sa_handler = osap->sa_handler;
874 sa.sa_flags = osap->sa_flags;
875 SIG2OSIG(osap->sa_mask, sa.sa_mask);
876 error = copyout(&sa, uap->osa, sizeof(sa));
881 #if !defined(__i386__)
882 /* Avoid replicating the same stub everywhere */
886 struct osigreturn_args *uap;
889 return (nosys(td, (struct nosys_args *)uap));
892 #endif /* COMPAT_43 */
895 * Initialize signal state for process 0;
896 * set to ignore signals that are ignored by default.
907 mtx_lock(&ps->ps_mtx);
908 for (i = 1; i <= NSIG; i++)
909 if (sigprop(i) & SA_IGNORE && i != SIGCONT)
910 SIGADDSET(ps->ps_sigignore, i);
911 mtx_unlock(&ps->ps_mtx);
916 * Reset signals for an exec of the specified process.
919 execsigs(struct proc *p)
926 * Reset caught signals. Held signals remain held
927 * through td_sigmask (unless they were caught,
928 * and are now ignored by default).
930 PROC_LOCK_ASSERT(p, MA_OWNED);
931 td = FIRST_THREAD_IN_PROC(p);
933 mtx_lock(&ps->ps_mtx);
934 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
935 sig = sig_ffs(&ps->ps_sigcatch);
936 SIGDELSET(ps->ps_sigcatch, sig);
937 if (sigprop(sig) & SA_IGNORE) {
939 SIGADDSET(ps->ps_sigignore, sig);
940 sigqueue_delete_proc(p, sig);
942 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
945 * Reset stack state to the user stack.
946 * Clear set of signals caught on the signal stack.
948 td->td_sigstk.ss_flags = SS_DISABLE;
949 td->td_sigstk.ss_size = 0;
950 td->td_sigstk.ss_sp = 0;
951 td->td_pflags &= ~TDP_ALTSTACK;
953 * Reset no zombies if child dies flag as Solaris does.
955 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
956 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
957 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
958 mtx_unlock(&ps->ps_mtx);
964 * Manipulate signal mask.
967 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
970 sigset_t new_block, oset1;
975 if (!(flags & SIGPROCMASK_PROC_LOCKED))
978 *oset = td->td_sigmask;
985 oset1 = td->td_sigmask;
986 SIGSETOR(td->td_sigmask, *set);
987 new_block = td->td_sigmask;
988 SIGSETNAND(new_block, oset1);
991 SIGSETNAND(td->td_sigmask, *set);
996 oset1 = td->td_sigmask;
997 if (flags & SIGPROCMASK_OLD)
998 SIGSETLO(td->td_sigmask, *set);
1000 td->td_sigmask = *set;
1001 new_block = td->td_sigmask;
1002 SIGSETNAND(new_block, oset1);
1011 * The new_block set contains signals that were not previously
1012 * blocked, but are blocked now.
1014 * In case we block any signal that was not previously blocked
1015 * for td, and process has the signal pending, try to schedule
1016 * signal delivery to some thread that does not block the
1017 * signal, possibly waking it up.
1019 if (p->p_numthreads != 1)
1020 reschedule_signals(p, new_block, flags);
1024 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1029 #ifndef _SYS_SYSPROTO_H_
1030 struct sigprocmask_args {
1032 const sigset_t *set;
1037 sys_sigprocmask(td, uap)
1038 register struct thread *td;
1039 struct sigprocmask_args *uap;
1042 sigset_t *setp, *osetp;
1045 setp = (uap->set != NULL) ? &set : NULL;
1046 osetp = (uap->oset != NULL) ? &oset : NULL;
1048 error = copyin(uap->set, setp, sizeof(set));
1052 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1053 if (osetp && !error) {
1054 error = copyout(osetp, uap->oset, sizeof(oset));
1059 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1060 #ifndef _SYS_SYSPROTO_H_
1061 struct osigprocmask_args {
1067 osigprocmask(td, uap)
1068 register struct thread *td;
1069 struct osigprocmask_args *uap;
1074 OSIG2SIG(uap->mask, set);
1075 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1076 SIG2OSIG(oset, td->td_retval[0]);
1079 #endif /* COMPAT_43 */
1082 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1088 error = copyin(uap->set, &set, sizeof(set));
1090 td->td_retval[0] = error;
1094 error = kern_sigtimedwait(td, set, &ksi, NULL);
1096 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1098 if (error == ERESTART)
1100 td->td_retval[0] = error;
1104 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1105 td->td_retval[0] = error;
1110 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1113 struct timespec *timeout;
1119 error = copyin(uap->timeout, &ts, sizeof(ts));
1127 error = copyin(uap->set, &set, sizeof(set));
1131 error = kern_sigtimedwait(td, set, &ksi, timeout);
1136 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1139 td->td_retval[0] = ksi.ksi_signo;
1144 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1150 error = copyin(uap->set, &set, sizeof(set));
1154 error = kern_sigtimedwait(td, set, &ksi, NULL);
1159 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1162 td->td_retval[0] = ksi.ksi_signo;
1167 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1168 struct timespec *timeout)
1171 sigset_t saved_mask, new_block;
1173 int error, sig, timo, timevalid = 0;
1174 struct timespec rts, ets, ts;
1182 if (timeout != NULL) {
1183 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1185 getnanouptime(&rts);
1187 timespecadd(&ets, timeout);
1191 /* Some signals can not be waited for. */
1192 SIG_CANTMASK(waitset);
1195 saved_mask = td->td_sigmask;
1196 SIGSETNAND(td->td_sigmask, waitset);
1198 mtx_lock(&ps->ps_mtx);
1200 mtx_unlock(&ps->ps_mtx);
1201 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1202 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1203 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1213 * POSIX says this must be checked after looking for pending
1216 if (timeout != NULL) {
1221 getnanouptime(&rts);
1222 if (timespeccmp(&rts, &ets, >=)) {
1227 timespecsub(&ts, &rts);
1228 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1234 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1236 if (timeout != NULL) {
1237 if (error == ERESTART) {
1238 /* Timeout can not be restarted. */
1240 } else if (error == EAGAIN) {
1241 /* We will calculate timeout by ourself. */
1247 new_block = saved_mask;
1248 SIGSETNAND(new_block, td->td_sigmask);
1249 td->td_sigmask = saved_mask;
1251 * Fewer signals can be delivered to us, reschedule signal
1254 if (p->p_numthreads != 1)
1255 reschedule_signals(p, new_block, 0);
1258 SDT_PROBE(proc, kernel, , signal__clear, sig, ksi, 0, 0, 0);
1260 if (ksi->ksi_code == SI_TIMER)
1261 itimer_accept(p, ksi->ksi_timerid, ksi);
1264 if (KTRPOINT(td, KTR_PSIG)) {
1267 mtx_lock(&ps->ps_mtx);
1268 action = ps->ps_sigact[_SIG_IDX(sig)];
1269 mtx_unlock(&ps->ps_mtx);
1270 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1280 #ifndef _SYS_SYSPROTO_H_
1281 struct sigpending_args {
1286 sys_sigpending(td, uap)
1288 struct sigpending_args *uap;
1290 struct proc *p = td->td_proc;
1294 pending = p->p_sigqueue.sq_signals;
1295 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1297 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1300 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1301 #ifndef _SYS_SYSPROTO_H_
1302 struct osigpending_args {
1307 osigpending(td, uap)
1309 struct osigpending_args *uap;
1311 struct proc *p = td->td_proc;
1315 pending = p->p_sigqueue.sq_signals;
1316 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1318 SIG2OSIG(pending, td->td_retval[0]);
1321 #endif /* COMPAT_43 */
1323 #if defined(COMPAT_43)
1325 * Generalized interface signal handler, 4.3-compatible.
1327 #ifndef _SYS_SYSPROTO_H_
1328 struct osigvec_args {
1338 register struct osigvec_args *uap;
1341 struct sigaction nsa, osa;
1342 register struct sigaction *nsap, *osap;
1345 if (uap->signum <= 0 || uap->signum >= ONSIG)
1347 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1348 osap = (uap->osv != NULL) ? &osa : NULL;
1350 error = copyin(uap->nsv, &vec, sizeof(vec));
1353 nsap->sa_handler = vec.sv_handler;
1354 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1355 nsap->sa_flags = vec.sv_flags;
1356 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1358 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1359 if (osap && !error) {
1360 vec.sv_handler = osap->sa_handler;
1361 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1362 vec.sv_flags = osap->sa_flags;
1363 vec.sv_flags &= ~SA_NOCLDWAIT;
1364 vec.sv_flags ^= SA_RESTART;
1365 error = copyout(&vec, uap->osv, sizeof(vec));
1370 #ifndef _SYS_SYSPROTO_H_
1371 struct osigblock_args {
1377 register struct thread *td;
1378 struct osigblock_args *uap;
1382 OSIG2SIG(uap->mask, set);
1383 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1384 SIG2OSIG(oset, td->td_retval[0]);
1388 #ifndef _SYS_SYSPROTO_H_
1389 struct osigsetmask_args {
1394 osigsetmask(td, uap)
1396 struct osigsetmask_args *uap;
1400 OSIG2SIG(uap->mask, set);
1401 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1402 SIG2OSIG(oset, td->td_retval[0]);
1405 #endif /* COMPAT_43 */
1408 * Suspend calling thread until signal, providing mask to be set in the
1411 #ifndef _SYS_SYSPROTO_H_
1412 struct sigsuspend_args {
1413 const sigset_t *sigmask;
1418 sys_sigsuspend(td, uap)
1420 struct sigsuspend_args *uap;
1425 error = copyin(uap->sigmask, &mask, sizeof(mask));
1428 return (kern_sigsuspend(td, mask));
1432 kern_sigsuspend(struct thread *td, sigset_t mask)
1434 struct proc *p = td->td_proc;
1438 * When returning from sigsuspend, we want
1439 * the old mask to be restored after the
1440 * signal handler has finished. Thus, we
1441 * save it here and mark the sigacts structure
1445 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1446 SIGPROCMASK_PROC_LOCKED);
1447 td->td_pflags |= TDP_OLDMASK;
1450 * Process signals now. Otherwise, we can get spurious wakeup
1451 * due to signal entered process queue, but delivered to other
1452 * thread. But sigsuspend should return only on signal
1455 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1456 for (has_sig = 0; !has_sig;) {
1457 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1460 thread_suspend_check(0);
1461 mtx_lock(&p->p_sigacts->ps_mtx);
1462 while ((sig = cursig(td)) != 0)
1463 has_sig += postsig(sig);
1464 mtx_unlock(&p->p_sigacts->ps_mtx);
1467 td->td_errno = EINTR;
1468 td->td_pflags |= TDP_NERRNO;
1469 return (EJUSTRETURN);
1472 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1474 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1475 * convention: libc stub passes mask, not pointer, to save a copyin.
1477 #ifndef _SYS_SYSPROTO_H_
1478 struct osigsuspend_args {
1484 osigsuspend(td, uap)
1486 struct osigsuspend_args *uap;
1490 OSIG2SIG(uap->mask, mask);
1491 return (kern_sigsuspend(td, mask));
1493 #endif /* COMPAT_43 */
1495 #if defined(COMPAT_43)
1496 #ifndef _SYS_SYSPROTO_H_
1497 struct osigstack_args {
1498 struct sigstack *nss;
1499 struct sigstack *oss;
1506 register struct osigstack_args *uap;
1508 struct sigstack nss, oss;
1511 if (uap->nss != NULL) {
1512 error = copyin(uap->nss, &nss, sizeof(nss));
1516 oss.ss_sp = td->td_sigstk.ss_sp;
1517 oss.ss_onstack = sigonstack(cpu_getstack(td));
1518 if (uap->nss != NULL) {
1519 td->td_sigstk.ss_sp = nss.ss_sp;
1520 td->td_sigstk.ss_size = 0;
1521 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1522 td->td_pflags |= TDP_ALTSTACK;
1524 if (uap->oss != NULL)
1525 error = copyout(&oss, uap->oss, sizeof(oss));
1529 #endif /* COMPAT_43 */
1531 #ifndef _SYS_SYSPROTO_H_
1532 struct sigaltstack_args {
1539 sys_sigaltstack(td, uap)
1541 register struct sigaltstack_args *uap;
1546 if (uap->ss != NULL) {
1547 error = copyin(uap->ss, &ss, sizeof(ss));
1551 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1552 (uap->oss != NULL) ? &oss : NULL);
1555 if (uap->oss != NULL)
1556 error = copyout(&oss, uap->oss, sizeof(stack_t));
1561 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1563 struct proc *p = td->td_proc;
1566 oonstack = sigonstack(cpu_getstack(td));
1569 *oss = td->td_sigstk;
1570 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1571 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1577 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1579 if (!(ss->ss_flags & SS_DISABLE)) {
1580 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1583 td->td_sigstk = *ss;
1584 td->td_pflags |= TDP_ALTSTACK;
1586 td->td_pflags &= ~TDP_ALTSTACK;
1593 * Common code for kill process group/broadcast kill.
1594 * cp is calling process.
1597 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1609 sx_slock(&allproc_lock);
1610 FOREACH_PROC_IN_SYSTEM(p) {
1612 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1613 p == td->td_proc || p->p_state == PRS_NEW) {
1617 err = p_cansignal(td, p, sig);
1620 pksignal(p, sig, ksi);
1623 else if (ret == ESRCH)
1627 sx_sunlock(&allproc_lock);
1629 sx_slock(&proctree_lock);
1632 * zero pgid means send to my process group.
1634 pgrp = td->td_proc->p_pgrp;
1637 pgrp = pgfind(pgid);
1639 sx_sunlock(&proctree_lock);
1643 sx_sunlock(&proctree_lock);
1644 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1646 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1647 p->p_state == PRS_NEW) {
1651 err = p_cansignal(td, p, sig);
1654 pksignal(p, sig, ksi);
1657 else if (ret == ESRCH)
1666 #ifndef _SYS_SYSPROTO_H_
1674 sys_kill(struct thread *td, struct kill_args *uap)
1681 * A process in capability mode can send signals only to himself.
1682 * The main rationale behind this is that abort(3) is implemented as
1683 * kill(getpid(), SIGABRT).
1685 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1688 AUDIT_ARG_SIGNUM(uap->signum);
1689 AUDIT_ARG_PID(uap->pid);
1690 if ((u_int)uap->signum > _SIG_MAXSIG)
1693 ksiginfo_init(&ksi);
1694 ksi.ksi_signo = uap->signum;
1695 ksi.ksi_code = SI_USER;
1696 ksi.ksi_pid = td->td_proc->p_pid;
1697 ksi.ksi_uid = td->td_ucred->cr_ruid;
1700 /* kill single process */
1701 if ((p = pfind(uap->pid)) == NULL) {
1702 if ((p = zpfind(uap->pid)) == NULL)
1705 AUDIT_ARG_PROCESS(p);
1706 error = p_cansignal(td, p, uap->signum);
1707 if (error == 0 && uap->signum)
1708 pksignal(p, uap->signum, &ksi);
1713 case -1: /* broadcast signal */
1714 return (killpg1(td, uap->signum, 0, 1, &ksi));
1715 case 0: /* signal own process group */
1716 return (killpg1(td, uap->signum, 0, 0, &ksi));
1717 default: /* negative explicit process group */
1718 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1726 struct pdkill_args *uap;
1730 cap_rights_t rights;
1733 AUDIT_ARG_SIGNUM(uap->signum);
1734 AUDIT_ARG_FD(uap->fd);
1735 if ((u_int)uap->signum > _SIG_MAXSIG)
1738 error = procdesc_find(td, uap->fd,
1739 cap_rights_init(&rights, CAP_PDKILL), &p);
1742 AUDIT_ARG_PROCESS(p);
1743 error = p_cansignal(td, p, uap->signum);
1744 if (error == 0 && uap->signum)
1745 kern_psignal(p, uap->signum);
1753 #if defined(COMPAT_43)
1754 #ifndef _SYS_SYSPROTO_H_
1755 struct okillpg_args {
1762 okillpg(struct thread *td, struct okillpg_args *uap)
1766 AUDIT_ARG_SIGNUM(uap->signum);
1767 AUDIT_ARG_PID(uap->pgid);
1768 if ((u_int)uap->signum > _SIG_MAXSIG)
1771 ksiginfo_init(&ksi);
1772 ksi.ksi_signo = uap->signum;
1773 ksi.ksi_code = SI_USER;
1774 ksi.ksi_pid = td->td_proc->p_pid;
1775 ksi.ksi_uid = td->td_ucred->cr_ruid;
1776 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1778 #endif /* COMPAT_43 */
1780 #ifndef _SYS_SYSPROTO_H_
1781 struct sigqueue_args {
1784 /* union sigval */ void *value;
1788 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1794 if ((u_int)uap->signum > _SIG_MAXSIG)
1798 * Specification says sigqueue can only send signal to
1804 if ((p = pfind(uap->pid)) == NULL) {
1805 if ((p = zpfind(uap->pid)) == NULL)
1808 error = p_cansignal(td, p, uap->signum);
1809 if (error == 0 && uap->signum != 0) {
1810 ksiginfo_init(&ksi);
1811 ksi.ksi_flags = KSI_SIGQ;
1812 ksi.ksi_signo = uap->signum;
1813 ksi.ksi_code = SI_QUEUE;
1814 ksi.ksi_pid = td->td_proc->p_pid;
1815 ksi.ksi_uid = td->td_ucred->cr_ruid;
1816 ksi.ksi_value.sival_ptr = uap->value;
1817 error = pksignal(p, ksi.ksi_signo, &ksi);
1824 * Send a signal to a process group.
1827 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1832 sx_slock(&proctree_lock);
1833 pgrp = pgfind(pgid);
1834 sx_sunlock(&proctree_lock);
1836 pgsignal(pgrp, sig, 0, ksi);
1843 * Send a signal to a process group. If checktty is 1,
1844 * limit to members which have a controlling terminal.
1847 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1852 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1853 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1855 if (p->p_state == PRS_NORMAL &&
1856 (checkctty == 0 || p->p_flag & P_CONTROLT))
1857 pksignal(p, sig, ksi);
1864 * Send a signal caused by a trap to the current thread. If it will be
1865 * caught immediately, deliver it with correct code. Otherwise, post it
1869 trapsignal(struct thread *td, ksiginfo_t *ksi)
1878 sig = ksi->ksi_signo;
1879 code = ksi->ksi_code;
1880 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1884 mtx_lock(&ps->ps_mtx);
1885 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1886 !SIGISMEMBER(td->td_sigmask, sig)) {
1887 td->td_ru.ru_nsignals++;
1889 if (KTRPOINT(curthread, KTR_PSIG))
1890 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1891 &td->td_sigmask, code);
1893 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1894 ksi, &td->td_sigmask);
1895 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1896 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1897 SIGADDSET(mask, sig);
1898 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1899 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1900 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1902 * See kern_sigaction() for origin of this code.
1904 SIGDELSET(ps->ps_sigcatch, sig);
1905 if (sig != SIGCONT &&
1906 sigprop(sig) & SA_IGNORE)
1907 SIGADDSET(ps->ps_sigignore, sig);
1908 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1910 mtx_unlock(&ps->ps_mtx);
1913 * Avoid a possible infinite loop if the thread
1914 * masking the signal or process is ignoring the
1917 if (kern_forcesigexit &&
1918 (SIGISMEMBER(td->td_sigmask, sig) ||
1919 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1920 SIGDELSET(td->td_sigmask, sig);
1921 SIGDELSET(ps->ps_sigcatch, sig);
1922 SIGDELSET(ps->ps_sigignore, sig);
1923 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1925 mtx_unlock(&ps->ps_mtx);
1926 p->p_code = code; /* XXX for core dump/debugger */
1927 p->p_sig = sig; /* XXX to verify code */
1928 tdsendsignal(p, td, sig, ksi);
1933 static struct thread *
1934 sigtd(struct proc *p, int sig, int prop)
1936 struct thread *td, *signal_td;
1938 PROC_LOCK_ASSERT(p, MA_OWNED);
1941 * Check if current thread can handle the signal without
1942 * switching context to another thread.
1944 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1947 FOREACH_THREAD_IN_PROC(p, td) {
1948 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1953 if (signal_td == NULL)
1954 signal_td = FIRST_THREAD_IN_PROC(p);
1959 * Send the signal to the process. If the signal has an action, the action
1960 * is usually performed by the target process rather than the caller; we add
1961 * the signal to the set of pending signals for the process.
1964 * o When a stop signal is sent to a sleeping process that takes the
1965 * default action, the process is stopped without awakening it.
1966 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1967 * regardless of the signal action (eg, blocked or ignored).
1969 * Other ignored signals are discarded immediately.
1971 * NB: This function may be entered from the debugger via the "kill" DDB
1972 * command. There is little that can be done to mitigate the possibly messy
1973 * side effects of this unwise possibility.
1976 kern_psignal(struct proc *p, int sig)
1980 ksiginfo_init(&ksi);
1981 ksi.ksi_signo = sig;
1982 ksi.ksi_code = SI_KERNEL;
1983 (void) tdsendsignal(p, NULL, sig, &ksi);
1987 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
1990 return (tdsendsignal(p, NULL, sig, ksi));
1993 /* Utility function for finding a thread to send signal event to. */
1995 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
1999 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2000 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2012 tdsignal(struct thread *td, int sig)
2016 ksiginfo_init(&ksi);
2017 ksi.ksi_signo = sig;
2018 ksi.ksi_code = SI_KERNEL;
2019 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2023 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2026 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2030 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2033 sigqueue_t *sigqueue;
2040 MPASS(td == NULL || p == td->td_proc);
2041 PROC_LOCK_ASSERT(p, MA_OWNED);
2043 if (!_SIG_VALID(sig))
2044 panic("%s(): invalid signal %d", __func__, sig);
2046 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2049 * IEEE Std 1003.1-2001: return success when killing a zombie.
2051 if (p->p_state == PRS_ZOMBIE) {
2052 if (ksi && (ksi->ksi_flags & KSI_INS))
2053 ksiginfo_tryfree(ksi);
2058 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2059 prop = sigprop(sig);
2062 td = sigtd(p, sig, prop);
2063 sigqueue = &p->p_sigqueue;
2065 sigqueue = &td->td_sigqueue;
2067 SDT_PROBE(proc, kernel, , signal__send, td, p, sig, 0, 0 );
2070 * If the signal is being ignored,
2071 * then we forget about it immediately.
2072 * (Note: we don't set SIGCONT in ps_sigignore,
2073 * and if it is set to SIG_IGN,
2074 * action will be SIG_DFL here.)
2076 mtx_lock(&ps->ps_mtx);
2077 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2078 SDT_PROBE(proc, kernel, , signal__discard, td, p, sig, 0, 0 );
2080 mtx_unlock(&ps->ps_mtx);
2081 if (ksi && (ksi->ksi_flags & KSI_INS))
2082 ksiginfo_tryfree(ksi);
2085 if (SIGISMEMBER(td->td_sigmask, sig))
2087 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2091 if (SIGISMEMBER(ps->ps_sigintr, sig))
2095 mtx_unlock(&ps->ps_mtx);
2098 sigqueue_delete_stopmask_proc(p);
2099 else if (prop & SA_STOP) {
2101 * If sending a tty stop signal to a member of an orphaned
2102 * process group, discard the signal here if the action
2103 * is default; don't stop the process below if sleeping,
2104 * and don't clear any pending SIGCONT.
2106 if ((prop & SA_TTYSTOP) &&
2107 (p->p_pgrp->pg_jobc == 0) &&
2108 (action == SIG_DFL)) {
2109 if (ksi && (ksi->ksi_flags & KSI_INS))
2110 ksiginfo_tryfree(ksi);
2113 sigqueue_delete_proc(p, SIGCONT);
2114 if (p->p_flag & P_CONTINUED) {
2115 p->p_flag &= ~P_CONTINUED;
2116 PROC_LOCK(p->p_pptr);
2117 sigqueue_take(p->p_ksi);
2118 PROC_UNLOCK(p->p_pptr);
2122 ret = sigqueue_add(sigqueue, sig, ksi);
2127 * Defer further processing for signals which are held,
2128 * except that stopped processes must be continued by SIGCONT.
2130 if (action == SIG_HOLD &&
2131 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2134 * SIGKILL: Remove procfs STOPEVENTs.
2136 if (sig == SIGKILL) {
2137 /* from procfs_ioctl.c: PIOCBIC */
2139 /* from procfs_ioctl.c: PIOCCONT */
2144 * Some signals have a process-wide effect and a per-thread
2145 * component. Most processing occurs when the process next
2146 * tries to cross the user boundary, however there are some
2147 * times when processing needs to be done immediately, such as
2148 * waking up threads so that they can cross the user boundary.
2149 * We try to do the per-process part here.
2151 if (P_SHOULDSTOP(p)) {
2152 KASSERT(!(p->p_flag & P_WEXIT),
2153 ("signal to stopped but exiting process"));
2154 if (sig == SIGKILL) {
2156 * If traced process is already stopped,
2157 * then no further action is necessary.
2159 if (p->p_flag & P_TRACED)
2162 * SIGKILL sets process running.
2163 * It will die elsewhere.
2164 * All threads must be restarted.
2166 p->p_flag &= ~P_STOPPED_SIG;
2170 if (prop & SA_CONT) {
2172 * If traced process is already stopped,
2173 * then no further action is necessary.
2175 if (p->p_flag & P_TRACED)
2178 * If SIGCONT is default (or ignored), we continue the
2179 * process but don't leave the signal in sigqueue as
2180 * it has no further action. If SIGCONT is held, we
2181 * continue the process and leave the signal in
2182 * sigqueue. If the process catches SIGCONT, let it
2183 * handle the signal itself. If it isn't waiting on
2184 * an event, it goes back to run state.
2185 * Otherwise, process goes back to sleep state.
2187 p->p_flag &= ~P_STOPPED_SIG;
2189 if (p->p_numthreads == p->p_suspcount) {
2191 p->p_flag |= P_CONTINUED;
2192 p->p_xstat = SIGCONT;
2193 PROC_LOCK(p->p_pptr);
2194 childproc_continued(p);
2195 PROC_UNLOCK(p->p_pptr);
2198 if (action == SIG_DFL) {
2199 thread_unsuspend(p);
2201 sigqueue_delete(sigqueue, sig);
2204 if (action == SIG_CATCH) {
2206 * The process wants to catch it so it needs
2207 * to run at least one thread, but which one?
2213 * The signal is not ignored or caught.
2215 thread_unsuspend(p);
2220 if (prop & SA_STOP) {
2222 * If traced process is already stopped,
2223 * then no further action is necessary.
2225 if (p->p_flag & P_TRACED)
2228 * Already stopped, don't need to stop again
2229 * (If we did the shell could get confused).
2230 * Just make sure the signal STOP bit set.
2232 p->p_flag |= P_STOPPED_SIG;
2233 sigqueue_delete(sigqueue, sig);
2238 * All other kinds of signals:
2239 * If a thread is sleeping interruptibly, simulate a
2240 * wakeup so that when it is continued it will be made
2241 * runnable and can look at the signal. However, don't make
2242 * the PROCESS runnable, leave it stopped.
2243 * It may run a bit until it hits a thread_suspend_check().
2248 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2249 wakeup_swapper = sleepq_abort(td, intrval);
2256 * Mutexes are short lived. Threads waiting on them will
2257 * hit thread_suspend_check() soon.
2259 } else if (p->p_state == PRS_NORMAL) {
2260 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2261 tdsigwakeup(td, sig, action, intrval);
2265 MPASS(action == SIG_DFL);
2267 if (prop & SA_STOP) {
2268 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2270 p->p_flag |= P_STOPPED_SIG;
2273 sig_suspend_threads(td, p, 1);
2274 if (p->p_numthreads == p->p_suspcount) {
2276 * only thread sending signal to another
2277 * process can reach here, if thread is sending
2278 * signal to its process, because thread does
2279 * not suspend itself here, p_numthreads
2280 * should never be equal to p_suspcount.
2284 sigqueue_delete_proc(p, p->p_xstat);
2290 /* Not in "NORMAL" state. discard the signal. */
2291 sigqueue_delete(sigqueue, sig);
2296 * The process is not stopped so we need to apply the signal to all the
2300 tdsigwakeup(td, sig, action, intrval);
2302 thread_unsuspend(p);
2305 /* If we jump here, proc slock should not be owned. */
2306 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2311 * The force of a signal has been directed against a single
2312 * thread. We need to see what we can do about knocking it
2313 * out of any sleep it may be in etc.
2316 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2318 struct proc *p = td->td_proc;
2323 PROC_LOCK_ASSERT(p, MA_OWNED);
2324 prop = sigprop(sig);
2329 * Bring the priority of a thread up if we want it to get
2330 * killed in this lifetime.
2332 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2333 sched_prio(td, PUSER);
2334 if (TD_ON_SLEEPQ(td)) {
2336 * If thread is sleeping uninterruptibly
2337 * we can't interrupt the sleep... the signal will
2338 * be noticed when the process returns through
2339 * trap() or syscall().
2341 if ((td->td_flags & TDF_SINTR) == 0)
2344 * If SIGCONT is default (or ignored) and process is
2345 * asleep, we are finished; the process should not
2348 if ((prop & SA_CONT) && action == SIG_DFL) {
2351 sigqueue_delete(&p->p_sigqueue, sig);
2353 * It may be on either list in this state.
2354 * Remove from both for now.
2356 sigqueue_delete(&td->td_sigqueue, sig);
2361 * Don't awaken a sleeping thread for SIGSTOP if the
2362 * STOP signal is deferred.
2364 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2368 * Give low priority threads a better chance to run.
2370 if (td->td_priority > PUSER)
2371 sched_prio(td, PUSER);
2373 wakeup_swapper = sleepq_abort(td, intrval);
2376 * Other states do nothing with the signal immediately,
2377 * other than kicking ourselves if we are running.
2378 * It will either never be noticed, or noticed very soon.
2381 if (TD_IS_RUNNING(td) && td != curthread)
2393 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2397 PROC_LOCK_ASSERT(p, MA_OWNED);
2398 PROC_SLOCK_ASSERT(p, MA_OWNED);
2400 FOREACH_THREAD_IN_PROC(p, td2) {
2402 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2403 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2404 (td2->td_flags & TDF_SINTR)) {
2405 if (td2->td_flags & TDF_SBDRY) {
2407 * Once a thread is asleep with
2408 * TDF_SBDRY set, it should never
2409 * become suspended due to this check.
2411 KASSERT(!TD_IS_SUSPENDED(td2),
2412 ("thread with deferred stops suspended"));
2413 } else if (!TD_IS_SUSPENDED(td2)) {
2414 thread_suspend_one(td2);
2416 } else if (!TD_IS_SUSPENDED(td2)) {
2417 if (sending || td != td2)
2418 td2->td_flags |= TDF_ASTPENDING;
2420 if (TD_IS_RUNNING(td2) && td2 != td)
2421 forward_signal(td2);
2429 ptracestop(struct thread *td, int sig)
2431 struct proc *p = td->td_proc;
2433 PROC_LOCK_ASSERT(p, MA_OWNED);
2434 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2435 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2436 &p->p_mtx.lock_object, "Stopping for traced signal");
2438 td->td_dbgflags |= TDB_XSIG;
2441 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2442 if (p->p_flag & P_SINGLE_EXIT) {
2443 td->td_dbgflags &= ~TDB_XSIG;
2448 * Just make wait() to work, the last stopped thread
2453 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2454 sig_suspend_threads(td, p, 0);
2455 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2456 td->td_dbgflags &= ~TDB_STOPATFORK;
2457 cv_broadcast(&p->p_dbgwait);
2460 thread_suspend_switch(td);
2461 if (p->p_xthread == td)
2462 p->p_xthread = NULL;
2463 if (!(p->p_flag & P_TRACED))
2465 if (td->td_dbgflags & TDB_SUSPEND) {
2466 if (p->p_flag & P_SINGLE_EXIT)
2472 return (td->td_xsig);
2476 reschedule_signals(struct proc *p, sigset_t block, int flags)
2482 PROC_LOCK_ASSERT(p, MA_OWNED);
2483 if (SIGISEMPTY(p->p_siglist))
2486 SIGSETAND(block, p->p_siglist);
2487 while ((sig = sig_ffs(&block)) != 0) {
2488 SIGDELSET(block, sig);
2489 td = sigtd(p, sig, 0);
2491 if (!(flags & SIGPROCMASK_PS_LOCKED))
2492 mtx_lock(&ps->ps_mtx);
2493 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2494 tdsigwakeup(td, sig, SIG_CATCH,
2495 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2497 if (!(flags & SIGPROCMASK_PS_LOCKED))
2498 mtx_unlock(&ps->ps_mtx);
2503 tdsigcleanup(struct thread *td)
2509 PROC_LOCK_ASSERT(p, MA_OWNED);
2511 sigqueue_flush(&td->td_sigqueue);
2512 if (p->p_numthreads == 1)
2516 * Since we cannot handle signals, notify signal post code
2517 * about this by filling the sigmask.
2519 * Also, if needed, wake up thread(s) that do not block the
2520 * same signals as the exiting thread, since the thread might
2521 * have been selected for delivery and woken up.
2523 SIGFILLSET(unblocked);
2524 SIGSETNAND(unblocked, td->td_sigmask);
2525 SIGFILLSET(td->td_sigmask);
2526 reschedule_signals(p, unblocked, 0);
2531 * Defer the delivery of SIGSTOP for the current thread. Returns true
2532 * if stops were deferred and false if they were already deferred.
2540 if (td->td_flags & TDF_SBDRY)
2543 td->td_flags |= TDF_SBDRY;
2549 * Permit the delivery of SIGSTOP for the current thread. This does
2550 * not immediately suspend if a stop was posted. Instead, the thread
2551 * will suspend either via ast() or a subsequent interruptible sleep.
2560 td->td_flags &= ~TDF_SBDRY;
2565 * If the current process has received a signal (should be caught or cause
2566 * termination, should interrupt current syscall), return the signal number.
2567 * Stop signals with default action are processed immediately, then cleared;
2568 * they aren't returned. This is checked after each entry to the system for
2569 * a syscall or trap (though this can usually be done without calling issignal
2570 * by checking the pending signal masks in cursig.) The normal call
2573 * while (sig = cursig(curthread))
2577 issignal(struct thread *td)
2581 struct sigqueue *queue;
2582 sigset_t sigpending;
2583 int sig, prop, newsig;
2587 mtx_assert(&ps->ps_mtx, MA_OWNED);
2588 PROC_LOCK_ASSERT(p, MA_OWNED);
2590 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2592 sigpending = td->td_sigqueue.sq_signals;
2593 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2594 SIGSETNAND(sigpending, td->td_sigmask);
2596 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2597 SIG_STOPSIGMASK(sigpending);
2598 if (SIGISEMPTY(sigpending)) /* no signal to send */
2600 sig = sig_ffs(&sigpending);
2602 if (p->p_stops & S_SIG) {
2603 mtx_unlock(&ps->ps_mtx);
2604 stopevent(p, S_SIG, sig);
2605 mtx_lock(&ps->ps_mtx);
2609 * We should see pending but ignored signals
2610 * only if P_TRACED was on when they were posted.
2612 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2613 sigqueue_delete(&td->td_sigqueue, sig);
2614 sigqueue_delete(&p->p_sigqueue, sig);
2617 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) {
2619 * If traced, always stop.
2620 * Remove old signal from queue before the stop.
2621 * XXX shrug off debugger, it causes siginfo to
2624 queue = &td->td_sigqueue;
2625 td->td_dbgksi.ksi_signo = 0;
2626 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2627 queue = &p->p_sigqueue;
2628 sigqueue_get(queue, sig, &td->td_dbgksi);
2631 mtx_unlock(&ps->ps_mtx);
2632 newsig = ptracestop(td, sig);
2633 mtx_lock(&ps->ps_mtx);
2635 if (sig != newsig) {
2638 * If parent wants us to take the signal,
2639 * then it will leave it in p->p_xstat;
2640 * otherwise we just look for signals again.
2647 * Put the new signal into td_sigqueue. If the
2648 * signal is being masked, look for other
2651 sigqueue_add(queue, sig, NULL);
2652 if (SIGISMEMBER(td->td_sigmask, sig))
2656 if (td->td_dbgksi.ksi_signo != 0) {
2657 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2658 if (sigqueue_add(&td->td_sigqueue, sig,
2659 &td->td_dbgksi) != 0)
2660 td->td_dbgksi.ksi_signo = 0;
2662 if (td->td_dbgksi.ksi_signo == 0)
2663 sigqueue_add(&td->td_sigqueue, sig,
2668 * If the traced bit got turned off, go back up
2669 * to the top to rescan signals. This ensures
2670 * that p_sig* and p_sigact are consistent.
2672 if ((p->p_flag & P_TRACED) == 0)
2676 prop = sigprop(sig);
2679 * Decide whether the signal should be returned.
2680 * Return the signal's number, or fall through
2681 * to clear it from the pending mask.
2683 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2685 case (intptr_t)SIG_DFL:
2687 * Don't take default actions on system processes.
2689 if (p->p_pid <= 1) {
2692 * Are you sure you want to ignore SIGSEGV
2695 printf("Process (pid %lu) got signal %d\n",
2696 (u_long)p->p_pid, sig);
2698 break; /* == ignore */
2701 * If there is a pending stop signal to process
2702 * with default action, stop here,
2703 * then clear the signal. However,
2704 * if process is member of an orphaned
2705 * process group, ignore tty stop signals.
2707 if (prop & SA_STOP) {
2708 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2709 (p->p_pgrp->pg_jobc == 0 &&
2711 break; /* == ignore */
2712 mtx_unlock(&ps->ps_mtx);
2713 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2714 &p->p_mtx.lock_object, "Catching SIGSTOP");
2715 p->p_flag |= P_STOPPED_SIG;
2718 sig_suspend_threads(td, p, 0);
2719 thread_suspend_switch(td);
2721 mtx_lock(&ps->ps_mtx);
2723 } else if (prop & SA_IGNORE) {
2725 * Except for SIGCONT, shouldn't get here.
2726 * Default action is to ignore; drop it.
2728 break; /* == ignore */
2733 case (intptr_t)SIG_IGN:
2735 * Masking above should prevent us ever trying
2736 * to take action on an ignored signal other
2737 * than SIGCONT, unless process is traced.
2739 if ((prop & SA_CONT) == 0 &&
2740 (p->p_flag & P_TRACED) == 0)
2741 printf("issignal\n");
2742 break; /* == ignore */
2746 * This signal has an action, let
2747 * postsig() process it.
2751 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2752 sigqueue_delete(&p->p_sigqueue, sig);
2758 thread_stopped(struct proc *p)
2762 PROC_LOCK_ASSERT(p, MA_OWNED);
2763 PROC_SLOCK_ASSERT(p, MA_OWNED);
2767 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2769 p->p_flag &= ~P_WAITED;
2770 PROC_LOCK(p->p_pptr);
2771 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2772 CLD_TRAPPED : CLD_STOPPED);
2773 PROC_UNLOCK(p->p_pptr);
2779 * Take the action for the specified signal
2780 * from the current set of pending signals.
2786 struct thread *td = curthread;
2787 register struct proc *p = td->td_proc;
2791 sigset_t returnmask, mask;
2793 KASSERT(sig != 0, ("postsig"));
2795 PROC_LOCK_ASSERT(p, MA_OWNED);
2797 mtx_assert(&ps->ps_mtx, MA_OWNED);
2798 ksiginfo_init(&ksi);
2799 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2800 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2802 ksi.ksi_signo = sig;
2803 if (ksi.ksi_code == SI_TIMER)
2804 itimer_accept(p, ksi.ksi_timerid, &ksi);
2805 action = ps->ps_sigact[_SIG_IDX(sig)];
2807 if (KTRPOINT(td, KTR_PSIG))
2808 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2809 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2811 if (p->p_stops & S_SIG) {
2812 mtx_unlock(&ps->ps_mtx);
2813 stopevent(p, S_SIG, sig);
2814 mtx_lock(&ps->ps_mtx);
2817 if (action == SIG_DFL) {
2819 * Default action, where the default is to kill
2820 * the process. (Other cases were ignored above.)
2822 mtx_unlock(&ps->ps_mtx);
2827 * If we get here, the signal must be caught.
2829 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2830 ("postsig action"));
2832 * Set the new mask value and also defer further
2833 * occurrences of this signal.
2835 * Special case: user has done a sigsuspend. Here the
2836 * current mask is not of interest, but rather the
2837 * mask from before the sigsuspend is what we want
2838 * restored after the signal processing is completed.
2840 if (td->td_pflags & TDP_OLDMASK) {
2841 returnmask = td->td_oldsigmask;
2842 td->td_pflags &= ~TDP_OLDMASK;
2844 returnmask = td->td_sigmask;
2846 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2847 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2848 SIGADDSET(mask, sig);
2849 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2850 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2852 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2854 * See kern_sigaction() for origin of this code.
2856 SIGDELSET(ps->ps_sigcatch, sig);
2857 if (sig != SIGCONT &&
2858 sigprop(sig) & SA_IGNORE)
2859 SIGADDSET(ps->ps_sigignore, sig);
2860 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2862 td->td_ru.ru_nsignals++;
2863 if (p->p_sig == sig) {
2867 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2873 * Kill the current process for stated reason.
2881 PROC_LOCK_ASSERT(p, MA_OWNED);
2882 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2884 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2885 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2886 p->p_flag |= P_WKILLED;
2887 kern_psignal(p, SIGKILL);
2891 * Force the current process to exit with the specified signal, dumping core
2892 * if appropriate. We bypass the normal tests for masked and caught signals,
2893 * allowing unrecoverable failures to terminate the process without changing
2894 * signal state. Mark the accounting record with the signal termination.
2895 * If dumping core, save the signal number for the debugger. Calls exit and
2903 struct proc *p = td->td_proc;
2905 PROC_LOCK_ASSERT(p, MA_OWNED);
2906 p->p_acflag |= AXSIG;
2908 * We must be single-threading to generate a core dump. This
2909 * ensures that the registers in the core file are up-to-date.
2910 * Also, the ELF dump handler assumes that the thread list doesn't
2911 * change out from under it.
2913 * XXX If another thread attempts to single-thread before us
2914 * (e.g. via fork()), we won't get a dump at all.
2916 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2919 * Log signals which would cause core dumps
2920 * (Log as LOG_INFO to appease those who don't want
2922 * XXX : Todo, as well as euid, write out ruid too
2923 * Note that coredump() drops proc lock.
2925 if (coredump(td) == 0)
2927 if (kern_logsigexit)
2929 "pid %d (%s), uid %d: exited on signal %d%s\n",
2930 p->p_pid, p->p_comm,
2931 td->td_ucred ? td->td_ucred->cr_uid : -1,
2933 sig & WCOREFLAG ? " (core dumped)" : "");
2936 exit1(td, W_EXITCODE(0, sig));
2941 * Send queued SIGCHLD to parent when child process's state
2945 sigparent(struct proc *p, int reason, int status)
2947 PROC_LOCK_ASSERT(p, MA_OWNED);
2948 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2950 if (p->p_ksi != NULL) {
2951 p->p_ksi->ksi_signo = SIGCHLD;
2952 p->p_ksi->ksi_code = reason;
2953 p->p_ksi->ksi_status = status;
2954 p->p_ksi->ksi_pid = p->p_pid;
2955 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2956 if (KSI_ONQ(p->p_ksi))
2959 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2963 childproc_jobstate(struct proc *p, int reason, int sig)
2967 PROC_LOCK_ASSERT(p, MA_OWNED);
2968 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2971 * Wake up parent sleeping in kern_wait(), also send
2972 * SIGCHLD to parent, but SIGCHLD does not guarantee
2973 * that parent will awake, because parent may masked
2976 p->p_pptr->p_flag |= P_STATCHILD;
2979 ps = p->p_pptr->p_sigacts;
2980 mtx_lock(&ps->ps_mtx);
2981 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2982 mtx_unlock(&ps->ps_mtx);
2983 sigparent(p, reason, sig);
2985 mtx_unlock(&ps->ps_mtx);
2989 childproc_stopped(struct proc *p, int reason)
2991 /* p_xstat is a plain signal number, not a full wait() status here. */
2992 childproc_jobstate(p, reason, p->p_xstat);
2996 childproc_continued(struct proc *p)
2998 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3002 childproc_exited(struct proc *p)
3005 int xstat = p->p_xstat; /* convert to int */
3008 if (WCOREDUMP(xstat))
3009 reason = CLD_DUMPED, status = WTERMSIG(xstat);
3010 else if (WIFSIGNALED(xstat))
3011 reason = CLD_KILLED, status = WTERMSIG(xstat);
3013 reason = CLD_EXITED, status = WEXITSTATUS(xstat);
3015 * XXX avoid calling wakeup(p->p_pptr), the work is
3018 sigparent(p, reason, status);
3022 * We only have 1 character for the core count in the format
3023 * string, so the range will be 0-9
3025 #define MAX_NUM_CORES 10
3026 static int num_cores = 5;
3029 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3034 new_val = num_cores;
3035 error = sysctl_handle_int(oidp, &new_val, 0, req);
3036 if (error != 0 || req->newptr == NULL)
3038 if (new_val > MAX_NUM_CORES)
3039 new_val = MAX_NUM_CORES;
3042 num_cores = new_val;
3045 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3046 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3048 #if defined(COMPRESS_USER_CORES)
3049 int compress_user_cores = 1;
3050 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
3051 &compress_user_cores, 0, "Compression of user corefiles");
3053 int compress_user_cores_gzlevel = -1; /* default level */
3054 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
3055 &compress_user_cores_gzlevel, -1, "Corefile gzip compression level");
3057 #define GZ_SUFFIX ".gz"
3058 #define GZ_SUFFIX_LEN 3
3061 static char corefilename[MAXPATHLEN] = {"%N.core"};
3062 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3063 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3064 sizeof(corefilename), "Process corefile name format string");
3067 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3068 * Expand the name described in corefilename, using name, uid, and pid
3069 * and open/create core file.
3070 * corefilename is a printf-like string, with three format specifiers:
3071 * %N name of process ("name")
3072 * %P process id (pid)
3074 * For example, "%N.core" is the default; they can be disabled completely
3075 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3076 * This is controlled by the sysctl variable kern.corefile (see above).
3079 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3080 int compress, struct vnode **vpp, char **namep)
3082 struct nameidata nd;
3085 char *hostname, *name;
3086 int indexpos, i, error, cmode, flags, oflags;
3089 format = corefilename;
3090 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3092 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3093 for (i = 0; format[i] != '\0'; i++) {
3094 switch (format[i]) {
3095 case '%': /* Format character */
3097 switch (format[i]) {
3099 sbuf_putc(&sb, '%');
3101 case 'H': /* hostname */
3102 if (hostname == NULL) {
3103 hostname = malloc(MAXHOSTNAMELEN,
3106 getcredhostname(td->td_ucred, hostname,
3108 sbuf_printf(&sb, "%s", hostname);
3110 case 'I': /* autoincrementing index */
3111 sbuf_printf(&sb, "0");
3112 indexpos = sbuf_len(&sb) - 1;
3114 case 'N': /* process name */
3115 sbuf_printf(&sb, "%s", comm);
3117 case 'P': /* process id */
3118 sbuf_printf(&sb, "%u", pid);
3120 case 'U': /* user id */
3121 sbuf_printf(&sb, "%u", uid);
3125 "Unknown format character %c in "
3126 "corename `%s'\n", format[i], format);
3131 sbuf_putc(&sb, format[i]);
3135 free(hostname, M_TEMP);
3136 #ifdef COMPRESS_USER_CORES
3138 sbuf_printf(&sb, GZ_SUFFIX);
3140 if (sbuf_error(&sb) != 0) {
3141 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3142 "long\n", (long)pid, comm, (u_long)uid);
3150 cmode = S_IRUSR | S_IWUSR;
3151 oflags = VN_OPEN_NOAUDIT | (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3154 * If the core format has a %I in it, then we need to check
3155 * for existing corefiles before returning a name.
3156 * To do this we iterate over 0..num_cores to find a
3157 * non-existing core file name to use.
3159 if (indexpos != -1) {
3160 for (i = 0; i < num_cores; i++) {
3161 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3162 name[indexpos] = '0' + i;
3163 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3164 error = vn_open_cred(&nd, &flags, cmode, oflags,
3165 td->td_ucred, NULL);
3167 if (error == EEXIST)
3170 "pid %d (%s), uid (%u): Path `%s' failed "
3171 "on initial open test, error = %d\n",
3172 pid, comm, uid, name, error);
3178 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3179 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3180 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3184 audit_proc_coredump(td, name, error);
3189 NDFREE(&nd, NDF_ONLY_PNBUF);
3196 * Dump a process' core. The main routine does some
3197 * policy checking, and creates the name of the coredump;
3198 * then it passes on a vnode and a size limit to the process-specific
3199 * coredump routine if there is one; if there _is not_ one, it returns
3200 * ENOSYS; otherwise it returns the error from the process-specific routine.
3204 coredump(struct thread *td)
3206 struct proc *p = td->td_proc;
3207 struct ucred *cred = td->td_ucred;
3211 int error, error1, locked;
3213 char *name; /* name of corefile */
3217 #ifdef COMPRESS_USER_CORES
3218 compress = compress_user_cores;
3222 PROC_LOCK_ASSERT(p, MA_OWNED);
3223 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3224 _STOPEVENT(p, S_CORE, 0);
3226 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0)) {
3232 * Note that the bulk of limit checking is done after
3233 * the corefile is created. The exception is if the limit
3234 * for corefiles is 0, in which case we don't bother
3235 * creating the corefile at all. This layout means that
3236 * a corefile is truncated instead of not being created,
3237 * if it is larger than the limit.
3239 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3240 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3247 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress,
3252 /* Don't dump to non-regular files or files with links. */
3253 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3254 vattr.va_nlink != 1) {
3261 lf.l_whence = SEEK_SET;
3264 lf.l_type = F_WRLCK;
3265 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3267 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3268 lf.l_type = F_UNLCK;
3270 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3271 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3273 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3281 if (set_core_nodump_flag)
3282 vattr.va_flags = UF_NODUMP;
3283 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3284 VOP_SETATTR(vp, &vattr, cred);
3286 vn_finished_write(mp);
3288 p->p_acflag |= ACORE;
3291 if (p->p_sysent->sv_coredump != NULL) {
3292 error = p->p_sysent->sv_coredump(td, vp, limit,
3293 compress ? IMGACT_CORE_COMPRESS : 0);
3299 lf.l_type = F_UNLCK;
3300 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3303 error1 = vn_close(vp, FWRITE, cred, td);
3308 audit_proc_coredump(td, name, error);
3315 * Nonexistent system call-- signal process (may want to handle it). Flag
3316 * error in case process won't see signal immediately (blocked or ignored).
3318 #ifndef _SYS_SYSPROTO_H_
3327 struct nosys_args *args;
3329 struct proc *p = td->td_proc;
3332 tdsignal(td, SIGSYS);
3338 * Send a SIGIO or SIGURG signal to a process or process group using stored
3339 * credentials rather than those of the current process.
3342 pgsigio(sigiop, sig, checkctty)
3343 struct sigio **sigiop;
3347 struct sigio *sigio;
3349 ksiginfo_init(&ksi);
3350 ksi.ksi_signo = sig;
3351 ksi.ksi_code = SI_KERNEL;
3355 if (sigio == NULL) {
3359 if (sigio->sio_pgid > 0) {
3360 PROC_LOCK(sigio->sio_proc);
3361 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3362 kern_psignal(sigio->sio_proc, sig);
3363 PROC_UNLOCK(sigio->sio_proc);
3364 } else if (sigio->sio_pgid < 0) {
3367 PGRP_LOCK(sigio->sio_pgrp);
3368 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3370 if (p->p_state == PRS_NORMAL &&
3371 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3372 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3373 kern_psignal(p, sig);
3376 PGRP_UNLOCK(sigio->sio_pgrp);
3382 filt_sigattach(struct knote *kn)
3384 struct proc *p = curproc;
3386 kn->kn_ptr.p_proc = p;
3387 kn->kn_flags |= EV_CLEAR; /* automatically set */
3389 knlist_add(&p->p_klist, kn, 0);
3395 filt_sigdetach(struct knote *kn)
3397 struct proc *p = kn->kn_ptr.p_proc;
3399 knlist_remove(&p->p_klist, kn, 0);
3403 * signal knotes are shared with proc knotes, so we apply a mask to
3404 * the hint in order to differentiate them from process hints. This
3405 * could be avoided by using a signal-specific knote list, but probably
3406 * isn't worth the trouble.
3409 filt_signal(struct knote *kn, long hint)
3412 if (hint & NOTE_SIGNAL) {
3413 hint &= ~NOTE_SIGNAL;
3415 if (kn->kn_id == hint)
3418 return (kn->kn_data != 0);
3426 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3428 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3433 sigacts_free(struct sigacts *ps)
3436 if (refcount_release(&ps->ps_refcnt) == 0)
3438 mtx_destroy(&ps->ps_mtx);
3439 free(ps, M_SUBPROC);
3443 sigacts_hold(struct sigacts *ps)
3446 refcount_acquire(&ps->ps_refcnt);
3451 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3454 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3455 mtx_lock(&src->ps_mtx);
3456 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3457 mtx_unlock(&src->ps_mtx);
3461 sigacts_shared(struct sigacts *ps)
3464 return (ps->ps_refcnt > 1);