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_ktrace.h"
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/signalvar.h>
46 #include <sys/vnode.h>
48 #include <sys/condvar.h>
49 #include <sys/event.h>
50 #include <sys/fcntl.h>
51 #include <sys/kernel.h>
54 #include <sys/ktrace.h>
56 #include <sys/malloc.h>
57 #include <sys/mutex.h>
58 #include <sys/namei.h>
60 #include <sys/posix4.h>
61 #include <sys/pioctl.h>
62 #include <sys/resourcevar.h>
63 #include <sys/sleepqueue.h>
67 #include <sys/syscallsubr.h>
68 #include <sys/sysctl.h>
69 #include <sys/sysent.h>
70 #include <sys/syslog.h>
71 #include <sys/sysproto.h>
72 #include <sys/timers.h>
73 #include <sys/unistd.h>
76 #include <vm/vm_extern.h>
79 #include <machine/cpu.h>
81 #include <security/audit/audit.h>
83 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
85 static int coredump(struct thread *);
86 static char *expand_name(const char *, uid_t, pid_t);
87 static int killpg1(struct thread *td, int sig, int pgid, int all);
88 static int issignal(struct thread *p);
89 static int sigprop(int sig);
90 static void tdsigwakeup(struct thread *, int, sig_t, int);
91 static void sig_suspend_threads(struct thread *, struct proc *, int);
92 static int filt_sigattach(struct knote *kn);
93 static void filt_sigdetach(struct knote *kn);
94 static int filt_signal(struct knote *kn, long hint);
95 static struct thread *sigtd(struct proc *p, int sig, int prop);
97 static int do_tdsignal(struct proc *, struct thread *, int, ksiginfo_t *);
99 static void sigqueue_start(void);
101 static uma_zone_t ksiginfo_zone = NULL;
102 struct filterops sig_filtops =
103 { 0, filt_sigattach, filt_sigdetach, filt_signal };
105 int kern_logsigexit = 1;
106 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
108 "Log processes quitting on abnormal signals to syslog(3)");
110 static int kern_forcesigexit = 1;
111 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
112 &kern_forcesigexit, 0, "Force trap signal to be handled");
114 SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0, "POSIX real time signal");
116 static int max_pending_per_proc = 128;
117 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
118 &max_pending_per_proc, 0, "Max pending signals per proc");
120 static int preallocate_siginfo = 1024;
121 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
122 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
123 &preallocate_siginfo, 0, "Preallocated signal memory size");
125 static int signal_overflow = 0;
126 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
127 &signal_overflow, 0, "Number of signals overflew");
129 static int signal_alloc_fail = 0;
130 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
131 &signal_alloc_fail, 0, "signals failed to be allocated");
133 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
136 * Policy -- Can ucred cr1 send SIGIO to process cr2?
137 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
138 * in the right situations.
140 #define CANSIGIO(cr1, cr2) \
141 ((cr1)->cr_uid == 0 || \
142 (cr1)->cr_ruid == (cr2)->cr_ruid || \
143 (cr1)->cr_uid == (cr2)->cr_ruid || \
144 (cr1)->cr_ruid == (cr2)->cr_uid || \
145 (cr1)->cr_uid == (cr2)->cr_uid)
148 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
149 &sugid_coredump, 0, "Enable coredumping set user/group ID processes");
151 static int do_coredump = 1;
152 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
153 &do_coredump, 0, "Enable/Disable coredumps");
155 static int set_core_nodump_flag = 0;
156 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
157 0, "Enable setting the NODUMP flag on coredump files");
160 * Signal properties and actions.
161 * The array below categorizes the signals and their default actions
162 * according to the following properties:
164 #define SA_KILL 0x01 /* terminates process by default */
165 #define SA_CORE 0x02 /* ditto and coredumps */
166 #define SA_STOP 0x04 /* suspend process */
167 #define SA_TTYSTOP 0x08 /* ditto, from tty */
168 #define SA_IGNORE 0x10 /* ignore by default */
169 #define SA_CONT 0x20 /* continue if suspended */
170 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
171 #define SA_PROC 0x80 /* deliverable to any thread */
173 static int sigproptbl[NSIG] = {
174 SA_KILL|SA_PROC, /* SIGHUP */
175 SA_KILL|SA_PROC, /* SIGINT */
176 SA_KILL|SA_CORE|SA_PROC, /* SIGQUIT */
177 SA_KILL|SA_CORE, /* SIGILL */
178 SA_KILL|SA_CORE, /* SIGTRAP */
179 SA_KILL|SA_CORE, /* SIGABRT */
180 SA_KILL|SA_CORE|SA_PROC, /* SIGEMT */
181 SA_KILL|SA_CORE, /* SIGFPE */
182 SA_KILL|SA_PROC, /* SIGKILL */
183 SA_KILL|SA_CORE, /* SIGBUS */
184 SA_KILL|SA_CORE, /* SIGSEGV */
185 SA_KILL|SA_CORE, /* SIGSYS */
186 SA_KILL|SA_PROC, /* SIGPIPE */
187 SA_KILL|SA_PROC, /* SIGALRM */
188 SA_KILL|SA_PROC, /* SIGTERM */
189 SA_IGNORE|SA_PROC, /* SIGURG */
190 SA_STOP|SA_PROC, /* SIGSTOP */
191 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTSTP */
192 SA_IGNORE|SA_CONT|SA_PROC, /* SIGCONT */
193 SA_IGNORE|SA_PROC, /* SIGCHLD */
194 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTIN */
195 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTOU */
196 SA_IGNORE|SA_PROC, /* SIGIO */
197 SA_KILL, /* SIGXCPU */
198 SA_KILL, /* SIGXFSZ */
199 SA_KILL|SA_PROC, /* SIGVTALRM */
200 SA_KILL|SA_PROC, /* SIGPROF */
201 SA_IGNORE|SA_PROC, /* SIGWINCH */
202 SA_IGNORE|SA_PROC, /* SIGINFO */
203 SA_KILL|SA_PROC, /* SIGUSR1 */
204 SA_KILL|SA_PROC, /* SIGUSR2 */
210 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
211 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
212 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
213 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
214 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
215 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
219 ksiginfo_alloc(int wait)
226 if (ksiginfo_zone != NULL)
227 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
232 ksiginfo_free(ksiginfo_t *ksi)
234 uma_zfree(ksiginfo_zone, ksi);
238 ksiginfo_tryfree(ksiginfo_t *ksi)
240 if (!(ksi->ksi_flags & KSI_EXT)) {
241 uma_zfree(ksiginfo_zone, ksi);
248 sigqueue_init(sigqueue_t *list, struct proc *p)
250 SIGEMPTYSET(list->sq_signals);
251 SIGEMPTYSET(list->sq_kill);
252 TAILQ_INIT(&list->sq_list);
254 list->sq_flags = SQ_INIT;
258 * Get a signal's ksiginfo.
260 * 0 - signal not found
261 * others - signal number
264 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
266 struct proc *p = sq->sq_proc;
267 struct ksiginfo *ksi, *next;
270 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
272 if (!SIGISMEMBER(sq->sq_signals, signo))
275 if (SIGISMEMBER(sq->sq_kill, signo)) {
277 SIGDELSET(sq->sq_kill, signo);
280 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
281 if (ksi->ksi_signo == signo) {
283 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
284 ksi->ksi_sigq = NULL;
285 ksiginfo_copy(ksi, si);
286 if (ksiginfo_tryfree(ksi) && p != NULL)
295 SIGDELSET(sq->sq_signals, signo);
296 si->ksi_signo = signo;
301 sigqueue_take(ksiginfo_t *ksi)
307 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
311 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
312 ksi->ksi_sigq = NULL;
313 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
316 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
317 kp = TAILQ_NEXT(kp, ksi_link)) {
318 if (kp->ksi_signo == ksi->ksi_signo)
321 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
322 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
326 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
328 struct proc *p = sq->sq_proc;
329 struct ksiginfo *ksi;
332 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
334 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
335 SIGADDSET(sq->sq_kill, signo);
339 /* directly insert the ksi, don't copy it */
340 if (si->ksi_flags & KSI_INS) {
341 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
346 if (__predict_false(ksiginfo_zone == NULL)) {
347 SIGADDSET(sq->sq_kill, signo);
351 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
354 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
360 ksiginfo_copy(si, ksi);
361 ksi->ksi_signo = signo;
362 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
366 if ((si->ksi_flags & KSI_TRAP) != 0) {
368 SIGADDSET(sq->sq_kill, signo);
377 SIGADDSET(sq->sq_signals, signo);
382 sigqueue_flush(sigqueue_t *sq)
384 struct proc *p = sq->sq_proc;
387 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
390 PROC_LOCK_ASSERT(p, MA_OWNED);
392 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
393 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
394 ksi->ksi_sigq = NULL;
395 if (ksiginfo_tryfree(ksi) && p != NULL)
399 SIGEMPTYSET(sq->sq_signals);
400 SIGEMPTYSET(sq->sq_kill);
404 sigqueue_collect_set(sigqueue_t *sq, sigset_t *set)
408 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
410 TAILQ_FOREACH(ksi, &sq->sq_list, ksi_link)
411 SIGADDSET(*set, ksi->ksi_signo);
412 SIGSETOR(*set, sq->sq_kill);
416 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, sigset_t *setp)
419 struct proc *p1, *p2;
420 ksiginfo_t *ksi, *next;
422 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
423 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
425 * make a copy, this allows setp to point to src or dst
426 * sq_signals without trouble.
431 /* Move siginfo to target list */
432 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
433 if (SIGISMEMBER(set, ksi->ksi_signo)) {
434 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
437 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
444 /* Move pending bits to target list */
447 SIGSETOR(dst->sq_kill, tmp);
448 SIGSETNAND(src->sq_kill, tmp);
450 tmp = src->sq_signals;
452 SIGSETOR(dst->sq_signals, tmp);
453 SIGSETNAND(src->sq_signals, tmp);
455 /* Finally, rescan src queue and set pending bits for it */
456 sigqueue_collect_set(src, &src->sq_signals);
460 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
465 SIGADDSET(set, signo);
466 sigqueue_move_set(src, dst, &set);
470 sigqueue_delete_set(sigqueue_t *sq, sigset_t *set)
472 struct proc *p = sq->sq_proc;
473 ksiginfo_t *ksi, *next;
475 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
477 /* Remove siginfo queue */
478 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
479 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
480 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
481 ksi->ksi_sigq = NULL;
482 if (ksiginfo_tryfree(ksi) && p != NULL)
486 SIGSETNAND(sq->sq_kill, *set);
487 SIGSETNAND(sq->sq_signals, *set);
488 /* Finally, rescan queue and set pending bits for it */
489 sigqueue_collect_set(sq, &sq->sq_signals);
493 sigqueue_delete(sigqueue_t *sq, int signo)
498 SIGADDSET(set, signo);
499 sigqueue_delete_set(sq, &set);
502 /* Remove a set of signals for a process */
504 sigqueue_delete_set_proc(struct proc *p, sigset_t *set)
509 PROC_LOCK_ASSERT(p, MA_OWNED);
511 sigqueue_init(&worklist, NULL);
512 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
515 FOREACH_THREAD_IN_PROC(p, td0)
516 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
519 sigqueue_flush(&worklist);
523 sigqueue_delete_proc(struct proc *p, int signo)
528 SIGADDSET(set, signo);
529 sigqueue_delete_set_proc(p, &set);
533 sigqueue_delete_stopmask_proc(struct proc *p)
538 SIGADDSET(set, SIGSTOP);
539 SIGADDSET(set, SIGTSTP);
540 SIGADDSET(set, SIGTTIN);
541 SIGADDSET(set, SIGTTOU);
542 sigqueue_delete_set_proc(p, &set);
546 * Determine signal that should be delivered to process p, the current
547 * process, 0 if none. If there is a pending stop signal with default
548 * action, the process stops in issignal().
551 cursig(struct thread *td)
553 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
554 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
555 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
556 return (SIGPENDING(td) ? issignal(td) : 0);
560 * Arrange for ast() to handle unmasked pending signals on return to user
561 * mode. This must be called whenever a signal is added to td_sigqueue or
562 * unmasked in td_sigmask.
565 signotify(struct thread *td)
576 PROC_LOCK_ASSERT(p, MA_OWNED);
579 * If our mask changed we may have to move signal that were
580 * previously masked by all threads to our sigqueue.
582 set = p->p_sigqueue.sq_signals;
584 if (p->p_flag & P_SA)
585 saved = p->p_sigqueue.sq_signals;
587 SIGSETNAND(set, td->td_sigmask);
588 if (! SIGISEMPTY(set))
589 sigqueue_move_set(&p->p_sigqueue, &td->td_sigqueue, &set);
590 if (SIGPENDING(td)) {
592 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
596 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) {
597 if (!SIGSETEQ(saved, p->p_sigqueue.sq_signals)) {
598 /* pending set changed */
599 p->p_flag |= P_SIGEVENT;
600 wakeup(&p->p_siglist);
607 sigonstack(size_t sp)
609 struct thread *td = curthread;
611 return ((td->td_pflags & TDP_ALTSTACK) ?
612 #if defined(COMPAT_43)
613 ((td->td_sigstk.ss_size == 0) ?
614 (td->td_sigstk.ss_flags & SS_ONSTACK) :
615 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
617 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
626 if (sig > 0 && sig < NSIG)
627 return (sigproptbl[_SIG_IDX(sig)]);
632 sig_ffs(sigset_t *set)
636 for (i = 0; i < _SIG_WORDS; i++)
638 return (ffs(set->__bits[i]) + (i * 32));
649 kern_sigaction(td, sig, act, oact, flags)
652 struct sigaction *act, *oact;
656 struct proc *p = td->td_proc;
658 if (!_SIG_VALID(sig))
663 mtx_lock(&ps->ps_mtx);
665 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
667 if (SIGISMEMBER(ps->ps_sigonstack, sig))
668 oact->sa_flags |= SA_ONSTACK;
669 if (!SIGISMEMBER(ps->ps_sigintr, sig))
670 oact->sa_flags |= SA_RESTART;
671 if (SIGISMEMBER(ps->ps_sigreset, sig))
672 oact->sa_flags |= SA_RESETHAND;
673 if (SIGISMEMBER(ps->ps_signodefer, sig))
674 oact->sa_flags |= SA_NODEFER;
675 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
676 oact->sa_flags |= SA_SIGINFO;
678 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
680 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
681 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
682 oact->sa_flags |= SA_NOCLDSTOP;
683 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
684 oact->sa_flags |= SA_NOCLDWAIT;
687 if ((sig == SIGKILL || sig == SIGSTOP) &&
688 act->sa_handler != SIG_DFL) {
689 mtx_unlock(&ps->ps_mtx);
695 * Change setting atomically.
698 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
699 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
700 if (act->sa_flags & SA_SIGINFO) {
701 ps->ps_sigact[_SIG_IDX(sig)] =
702 (__sighandler_t *)act->sa_sigaction;
703 SIGADDSET(ps->ps_siginfo, sig);
705 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
706 SIGDELSET(ps->ps_siginfo, sig);
708 if (!(act->sa_flags & SA_RESTART))
709 SIGADDSET(ps->ps_sigintr, sig);
711 SIGDELSET(ps->ps_sigintr, sig);
712 if (act->sa_flags & SA_ONSTACK)
713 SIGADDSET(ps->ps_sigonstack, sig);
715 SIGDELSET(ps->ps_sigonstack, sig);
716 if (act->sa_flags & SA_RESETHAND)
717 SIGADDSET(ps->ps_sigreset, sig);
719 SIGDELSET(ps->ps_sigreset, sig);
720 if (act->sa_flags & SA_NODEFER)
721 SIGADDSET(ps->ps_signodefer, sig);
723 SIGDELSET(ps->ps_signodefer, sig);
724 if (sig == SIGCHLD) {
725 if (act->sa_flags & SA_NOCLDSTOP)
726 ps->ps_flag |= PS_NOCLDSTOP;
728 ps->ps_flag &= ~PS_NOCLDSTOP;
729 if (act->sa_flags & SA_NOCLDWAIT) {
731 * Paranoia: since SA_NOCLDWAIT is implemented
732 * by reparenting the dying child to PID 1 (and
733 * trust it to reap the zombie), PID 1 itself
734 * is forbidden to set SA_NOCLDWAIT.
737 ps->ps_flag &= ~PS_NOCLDWAIT;
739 ps->ps_flag |= PS_NOCLDWAIT;
741 ps->ps_flag &= ~PS_NOCLDWAIT;
742 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
743 ps->ps_flag |= PS_CLDSIGIGN;
745 ps->ps_flag &= ~PS_CLDSIGIGN;
748 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
749 * and for signals set to SIG_DFL where the default is to
750 * ignore. However, don't put SIGCONT in ps_sigignore, as we
751 * have to restart the process.
753 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
754 (sigprop(sig) & SA_IGNORE &&
755 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
757 if ((p->p_flag & P_SA) &&
758 SIGISMEMBER(p->p_sigqueue.sq_signals, sig)) {
759 p->p_flag |= P_SIGEVENT;
760 wakeup(&p->p_siglist);
763 /* never to be seen again */
765 sigqueue_delete_proc(p, sig);
768 /* easier in psignal */
769 SIGADDSET(ps->ps_sigignore, sig);
770 SIGDELSET(ps->ps_sigcatch, sig);
772 SIGDELSET(ps->ps_sigignore, sig);
773 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
774 SIGDELSET(ps->ps_sigcatch, sig);
776 SIGADDSET(ps->ps_sigcatch, sig);
778 #ifdef COMPAT_FREEBSD4
779 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
780 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
781 (flags & KSA_FREEBSD4) == 0)
782 SIGDELSET(ps->ps_freebsd4, sig);
784 SIGADDSET(ps->ps_freebsd4, sig);
787 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
788 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
789 (flags & KSA_OSIGSET) == 0)
790 SIGDELSET(ps->ps_osigset, sig);
792 SIGADDSET(ps->ps_osigset, sig);
795 mtx_unlock(&ps->ps_mtx);
800 #ifndef _SYS_SYSPROTO_H_
801 struct sigaction_args {
803 struct sigaction *act;
804 struct sigaction *oact;
810 register struct sigaction_args *uap;
812 struct sigaction act, oact;
813 register struct sigaction *actp, *oactp;
816 actp = (uap->act != NULL) ? &act : NULL;
817 oactp = (uap->oact != NULL) ? &oact : NULL;
819 error = copyin(uap->act, actp, sizeof(act));
823 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
825 error = copyout(oactp, uap->oact, sizeof(oact));
829 #ifdef COMPAT_FREEBSD4
830 #ifndef _SYS_SYSPROTO_H_
831 struct freebsd4_sigaction_args {
833 struct sigaction *act;
834 struct sigaction *oact;
838 freebsd4_sigaction(td, uap)
840 register struct freebsd4_sigaction_args *uap;
842 struct sigaction act, oact;
843 register struct sigaction *actp, *oactp;
847 actp = (uap->act != NULL) ? &act : NULL;
848 oactp = (uap->oact != NULL) ? &oact : NULL;
850 error = copyin(uap->act, actp, sizeof(act));
854 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
856 error = copyout(oactp, uap->oact, sizeof(oact));
859 #endif /* COMAPT_FREEBSD4 */
861 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
862 #ifndef _SYS_SYSPROTO_H_
863 struct osigaction_args {
865 struct osigaction *nsa;
866 struct osigaction *osa;
872 register struct osigaction_args *uap;
874 struct osigaction sa;
875 struct sigaction nsa, osa;
876 register struct sigaction *nsap, *osap;
879 if (uap->signum <= 0 || uap->signum >= ONSIG)
882 nsap = (uap->nsa != NULL) ? &nsa : NULL;
883 osap = (uap->osa != NULL) ? &osa : NULL;
886 error = copyin(uap->nsa, &sa, sizeof(sa));
889 nsap->sa_handler = sa.sa_handler;
890 nsap->sa_flags = sa.sa_flags;
891 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
893 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
894 if (osap && !error) {
895 sa.sa_handler = osap->sa_handler;
896 sa.sa_flags = osap->sa_flags;
897 SIG2OSIG(osap->sa_mask, sa.sa_mask);
898 error = copyout(&sa, uap->osa, sizeof(sa));
903 #if !defined(__i386__)
904 /* Avoid replicating the same stub everywhere */
908 struct osigreturn_args *uap;
911 return (nosys(td, (struct nosys_args *)uap));
914 #endif /* COMPAT_43 */
917 * Initialize signal state for process 0;
918 * set to ignore signals that are ignored by default.
929 mtx_lock(&ps->ps_mtx);
930 for (i = 1; i <= NSIG; i++)
931 if (sigprop(i) & SA_IGNORE && i != SIGCONT)
932 SIGADDSET(ps->ps_sigignore, i);
933 mtx_unlock(&ps->ps_mtx);
938 * Reset signals for an exec of the specified process.
941 execsigs(struct proc *p)
948 * Reset caught signals. Held signals remain held
949 * through td_sigmask (unless they were caught,
950 * and are now ignored by default).
952 PROC_LOCK_ASSERT(p, MA_OWNED);
953 td = FIRST_THREAD_IN_PROC(p);
955 mtx_lock(&ps->ps_mtx);
956 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
957 sig = sig_ffs(&ps->ps_sigcatch);
958 SIGDELSET(ps->ps_sigcatch, sig);
959 if (sigprop(sig) & SA_IGNORE) {
961 SIGADDSET(ps->ps_sigignore, sig);
963 sigqueue_delete_proc(p, sig);
966 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
969 * Reset stack state to the user stack.
970 * Clear set of signals caught on the signal stack.
972 td->td_sigstk.ss_flags = SS_DISABLE;
973 td->td_sigstk.ss_size = 0;
974 td->td_sigstk.ss_sp = 0;
975 td->td_pflags &= ~TDP_ALTSTACK;
977 * Reset no zombies if child dies flag as Solaris does.
979 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
980 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
981 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
982 mtx_unlock(&ps->ps_mtx);
988 * Manipulate signal mask.
991 kern_sigprocmask(td, how, set, oset, old)
994 sigset_t *set, *oset;
999 PROC_LOCK(td->td_proc);
1001 *oset = td->td_sigmask;
1008 SIGSETOR(td->td_sigmask, *set);
1011 SIGSETNAND(td->td_sigmask, *set);
1017 SIGSETLO(td->td_sigmask, *set);
1019 td->td_sigmask = *set;
1027 PROC_UNLOCK(td->td_proc);
1031 #ifndef _SYS_SYSPROTO_H_
1032 struct sigprocmask_args {
1034 const sigset_t *set;
1039 sigprocmask(td, uap)
1040 register struct thread *td;
1041 struct sigprocmask_args *uap;
1044 sigset_t *setp, *osetp;
1047 setp = (uap->set != NULL) ? &set : NULL;
1048 osetp = (uap->oset != NULL) ? &oset : NULL;
1050 error = copyin(uap->set, setp, sizeof(set));
1054 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1055 if (osetp && !error) {
1056 error = copyout(osetp, uap->oset, sizeof(oset));
1061 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1062 #ifndef _SYS_SYSPROTO_H_
1063 struct osigprocmask_args {
1069 osigprocmask(td, uap)
1070 register struct thread *td;
1071 struct osigprocmask_args *uap;
1076 OSIG2SIG(uap->mask, set);
1077 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1078 SIG2OSIG(oset, td->td_retval[0]);
1081 #endif /* COMPAT_43 */
1084 sigwait(struct thread *td, struct sigwait_args *uap)
1090 error = copyin(uap->set, &set, sizeof(set));
1092 td->td_retval[0] = error;
1096 error = kern_sigtimedwait(td, set, &ksi, NULL);
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 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 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)
1173 int error, sig, hz, i, timevalid = 0;
1174 struct timespec rts, ets, ts;
1182 SIG_CANTMASK(waitset);
1186 savedmask = td->td_sigmask;
1188 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1190 getnanouptime(&rts);
1192 timespecadd(&ets, timeout);
1197 for (i = 1; i <= _SIG_MAXSIG; ++i) {
1198 if (!SIGISMEMBER(waitset, i))
1200 if (!SIGISMEMBER(td->td_sigqueue.sq_signals, i)) {
1201 if (SIGISMEMBER(p->p_sigqueue.sq_signals, i)) {
1203 if (p->p_flag & P_SA) {
1204 p->p_flag |= P_SIGEVENT;
1205 wakeup(&p->p_siglist);
1208 sigqueue_move(&p->p_sigqueue,
1209 &td->td_sigqueue, i);
1214 SIGFILLSET(td->td_sigmask);
1215 SIG_CANTMASK(td->td_sigmask);
1216 SIGDELSET(td->td_sigmask, i);
1217 mtx_lock(&ps->ps_mtx);
1219 mtx_unlock(&ps->ps_mtx);
1224 * Because cursig() may have stopped current thread,
1225 * after it is resumed, things may have already been
1226 * changed, it should rescan any pending signals.
1236 * POSIX says this must be checked after looking for pending
1244 getnanouptime(&rts);
1245 if (timespeccmp(&rts, &ets, >=)) {
1250 timespecsub(&ts, &rts);
1251 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1256 td->td_sigmask = savedmask;
1257 SIGSETNAND(td->td_sigmask, waitset);
1259 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz);
1261 if (error == ERESTART) {
1262 /* timeout can not be restarted. */
1264 } else if (error == EAGAIN) {
1265 /* will calculate timeout by ourself. */
1272 td->td_sigmask = savedmask;
1276 sigqueue_get(&td->td_sigqueue, sig, ksi);
1277 ksi->ksi_signo = sig;
1278 if (ksi->ksi_code == SI_TIMER)
1279 itimer_accept(p, ksi->ksi_timerid, ksi);
1283 if (KTRPOINT(td, KTR_PSIG)) {
1286 mtx_lock(&ps->ps_mtx);
1287 action = ps->ps_sigact[_SIG_IDX(sig)];
1288 mtx_unlock(&ps->ps_mtx);
1289 ktrpsig(sig, action, &td->td_sigmask, 0);
1299 #ifndef _SYS_SYSPROTO_H_
1300 struct sigpending_args {
1307 struct sigpending_args *uap;
1309 struct proc *p = td->td_proc;
1313 pending = p->p_sigqueue.sq_signals;
1314 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1316 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1319 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1320 #ifndef _SYS_SYSPROTO_H_
1321 struct osigpending_args {
1326 osigpending(td, uap)
1328 struct osigpending_args *uap;
1330 struct proc *p = td->td_proc;
1334 pending = p->p_sigqueue.sq_signals;
1335 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1337 SIG2OSIG(pending, td->td_retval[0]);
1340 #endif /* COMPAT_43 */
1342 #if defined(COMPAT_43)
1344 * Generalized interface signal handler, 4.3-compatible.
1346 #ifndef _SYS_SYSPROTO_H_
1347 struct osigvec_args {
1357 register struct osigvec_args *uap;
1360 struct sigaction nsa, osa;
1361 register struct sigaction *nsap, *osap;
1364 if (uap->signum <= 0 || uap->signum >= ONSIG)
1366 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1367 osap = (uap->osv != NULL) ? &osa : NULL;
1369 error = copyin(uap->nsv, &vec, sizeof(vec));
1372 nsap->sa_handler = vec.sv_handler;
1373 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1374 nsap->sa_flags = vec.sv_flags;
1375 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1377 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1378 if (osap && !error) {
1379 vec.sv_handler = osap->sa_handler;
1380 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1381 vec.sv_flags = osap->sa_flags;
1382 vec.sv_flags &= ~SA_NOCLDWAIT;
1383 vec.sv_flags ^= SA_RESTART;
1384 error = copyout(&vec, uap->osv, sizeof(vec));
1389 #ifndef _SYS_SYSPROTO_H_
1390 struct osigblock_args {
1396 register struct thread *td;
1397 struct osigblock_args *uap;
1399 struct proc *p = td->td_proc;
1402 OSIG2SIG(uap->mask, set);
1405 SIG2OSIG(td->td_sigmask, td->td_retval[0]);
1406 SIGSETOR(td->td_sigmask, set);
1411 #ifndef _SYS_SYSPROTO_H_
1412 struct osigsetmask_args {
1417 osigsetmask(td, uap)
1419 struct osigsetmask_args *uap;
1421 struct proc *p = td->td_proc;
1424 OSIG2SIG(uap->mask, set);
1427 SIG2OSIG(td->td_sigmask, td->td_retval[0]);
1428 SIGSETLO(td->td_sigmask, set);
1433 #endif /* COMPAT_43 */
1436 * Suspend calling thread until signal, providing mask to be set in the
1439 #ifndef _SYS_SYSPROTO_H_
1440 struct sigsuspend_args {
1441 const sigset_t *sigmask;
1448 struct sigsuspend_args *uap;
1453 error = copyin(uap->sigmask, &mask, sizeof(mask));
1456 return (kern_sigsuspend(td, mask));
1460 kern_sigsuspend(struct thread *td, sigset_t mask)
1462 struct proc *p = td->td_proc;
1465 * When returning from sigsuspend, we want
1466 * the old mask to be restored after the
1467 * signal handler has finished. Thus, we
1468 * save it here and mark the sigacts structure
1472 td->td_oldsigmask = td->td_sigmask;
1473 td->td_pflags |= TDP_OLDMASK;
1475 td->td_sigmask = mask;
1477 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0)
1480 /* always return EINTR rather than ERESTART... */
1484 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1486 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1487 * convention: libc stub passes mask, not pointer, to save a copyin.
1489 #ifndef _SYS_SYSPROTO_H_
1490 struct osigsuspend_args {
1496 osigsuspend(td, uap)
1498 struct osigsuspend_args *uap;
1500 struct proc *p = td->td_proc;
1504 td->td_oldsigmask = td->td_sigmask;
1505 td->td_pflags |= TDP_OLDMASK;
1506 OSIG2SIG(uap->mask, mask);
1508 SIGSETLO(td->td_sigmask, mask);
1510 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0)
1513 /* always return EINTR rather than ERESTART... */
1516 #endif /* COMPAT_43 */
1518 #if defined(COMPAT_43)
1519 #ifndef _SYS_SYSPROTO_H_
1520 struct osigstack_args {
1521 struct sigstack *nss;
1522 struct sigstack *oss;
1529 register struct osigstack_args *uap;
1531 struct sigstack nss, oss;
1534 if (uap->nss != NULL) {
1535 error = copyin(uap->nss, &nss, sizeof(nss));
1539 oss.ss_sp = td->td_sigstk.ss_sp;
1540 oss.ss_onstack = sigonstack(cpu_getstack(td));
1541 if (uap->nss != NULL) {
1542 td->td_sigstk.ss_sp = nss.ss_sp;
1543 td->td_sigstk.ss_size = 0;
1544 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1545 td->td_pflags |= TDP_ALTSTACK;
1547 if (uap->oss != NULL)
1548 error = copyout(&oss, uap->oss, sizeof(oss));
1552 #endif /* COMPAT_43 */
1554 #ifndef _SYS_SYSPROTO_H_
1555 struct sigaltstack_args {
1562 sigaltstack(td, uap)
1564 register struct sigaltstack_args *uap;
1569 if (uap->ss != NULL) {
1570 error = copyin(uap->ss, &ss, sizeof(ss));
1574 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1575 (uap->oss != NULL) ? &oss : NULL);
1578 if (uap->oss != NULL)
1579 error = copyout(&oss, uap->oss, sizeof(stack_t));
1584 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1586 struct proc *p = td->td_proc;
1589 oonstack = sigonstack(cpu_getstack(td));
1592 *oss = td->td_sigstk;
1593 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1594 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1600 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1602 if (!(ss->ss_flags & SS_DISABLE)) {
1603 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1606 td->td_sigstk = *ss;
1607 td->td_pflags |= TDP_ALTSTACK;
1609 td->td_pflags &= ~TDP_ALTSTACK;
1616 * Common code for kill process group/broadcast kill.
1617 * cp is calling process.
1620 killpg1(td, sig, pgid, all)
1621 register struct thread *td;
1624 register struct proc *p;
1632 sx_slock(&allproc_lock);
1633 FOREACH_PROC_IN_SYSTEM(p) {
1635 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1636 p == td->td_proc || p->p_state == PRS_NEW) {
1640 if (p_cansignal(td, p, sig) == 0) {
1647 sx_sunlock(&allproc_lock);
1649 sx_slock(&proctree_lock);
1652 * zero pgid means send to my process group.
1654 pgrp = td->td_proc->p_pgrp;
1657 pgrp = pgfind(pgid);
1659 sx_sunlock(&proctree_lock);
1663 sx_sunlock(&proctree_lock);
1664 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1666 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1667 p->p_state == PRS_NEW ) {
1671 if (p_cansignal(td, p, sig) == 0) {
1680 return (nfound ? 0 : ESRCH);
1683 #ifndef _SYS_SYSPROTO_H_
1692 register struct thread *td;
1693 register struct kill_args *uap;
1695 register struct proc *p;
1698 AUDIT_ARG(signum, uap->signum);
1699 AUDIT_ARG(pid, uap->pid);
1700 if ((u_int)uap->signum > _SIG_MAXSIG)
1704 /* kill single process */
1705 if ((p = pfind(uap->pid)) == NULL) {
1706 if ((p = zpfind(uap->pid)) == NULL)
1709 AUDIT_ARG(process, p);
1710 error = p_cansignal(td, p, uap->signum);
1711 if (error == 0 && uap->signum)
1712 psignal(p, uap->signum);
1717 case -1: /* broadcast signal */
1718 return (killpg1(td, uap->signum, 0, 1));
1719 case 0: /* signal own process group */
1720 return (killpg1(td, uap->signum, 0, 0));
1721 default: /* negative explicit process group */
1722 return (killpg1(td, uap->signum, -uap->pid, 0));
1727 #if defined(COMPAT_43)
1728 #ifndef _SYS_SYSPROTO_H_
1729 struct okillpg_args {
1738 register struct okillpg_args *uap;
1741 AUDIT_ARG(signum, uap->signum);
1742 AUDIT_ARG(pid, uap->pgid);
1743 if ((u_int)uap->signum > _SIG_MAXSIG)
1746 return (killpg1(td, uap->signum, uap->pgid, 0));
1748 #endif /* COMPAT_43 */
1750 #ifndef _SYS_SYSPROTO_H_
1751 struct sigqueue_args {
1754 /* union sigval */ void *value;
1758 sigqueue(struct thread *td, struct sigqueue_args *uap)
1764 if ((u_int)uap->signum > _SIG_MAXSIG)
1768 * Specification says sigqueue can only send signal to
1774 if ((p = pfind(uap->pid)) == NULL) {
1775 if ((p = zpfind(uap->pid)) == NULL)
1778 error = p_cansignal(td, p, uap->signum);
1779 if (error == 0 && uap->signum != 0) {
1780 ksiginfo_init(&ksi);
1781 ksi.ksi_signo = uap->signum;
1782 ksi.ksi_code = SI_QUEUE;
1783 ksi.ksi_pid = td->td_proc->p_pid;
1784 ksi.ksi_uid = td->td_ucred->cr_ruid;
1785 ksi.ksi_value.sival_ptr = uap->value;
1786 error = tdsignal(p, NULL, ksi.ksi_signo, &ksi);
1793 * Send a signal to a process group.
1802 sx_slock(&proctree_lock);
1803 pgrp = pgfind(pgid);
1804 sx_sunlock(&proctree_lock);
1806 pgsignal(pgrp, sig, 0);
1813 * Send a signal to a process group. If checktty is 1,
1814 * limit to members which have a controlling terminal.
1817 pgsignal(pgrp, sig, checkctty)
1821 register struct proc *p;
1824 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1825 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1827 if (checkctty == 0 || p->p_flag & P_CONTROLT)
1835 * Send a signal caused by a trap to the current thread. If it will be
1836 * caught immediately, deliver it with correct code. Otherwise, post it
1840 trapsignal(struct thread *td, ksiginfo_t *ksi)
1851 sig = ksi->ksi_signo;
1852 code = ksi->ksi_code;
1853 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1856 if (td->td_pflags & TDP_SA) {
1857 if (td->td_mailbox == NULL)
1858 thread_user_enter(td);
1860 SIGDELSET(td->td_sigmask, sig);
1863 * Force scheduling an upcall, so UTS has chance to
1864 * process the signal before thread runs again in
1868 td->td_upcall->ku_flags |= KUF_DOUPCALL;
1877 mtx_lock(&ps->ps_mtx);
1878 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1879 !SIGISMEMBER(td->td_sigmask, sig)) {
1880 td->td_ru.ru_nsignals++;
1882 if (KTRPOINT(curthread, KTR_PSIG))
1883 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1884 &td->td_sigmask, code);
1887 if (!(td->td_pflags & TDP_SA))
1888 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1889 ksi, &td->td_sigmask);
1891 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1892 ksi, &td->td_sigmask);
1895 else if (td->td_mailbox == NULL) {
1896 mtx_unlock(&ps->ps_mtx);
1897 /* UTS caused a sync signal */
1898 p->p_code = code; /* XXX for core dump/debugger */
1899 p->p_sig = sig; /* XXX to verify code */
1902 mtx_unlock(&ps->ps_mtx);
1903 SIGADDSET(td->td_sigmask, sig);
1905 error = copyout(&ksi->ksi_info, &td->td_mailbox->tm_syncsig,
1908 /* UTS memory corrupted */
1910 sigexit(td, SIGSEGV);
1911 mtx_lock(&ps->ps_mtx);
1914 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
1915 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1916 SIGADDSET(td->td_sigmask, sig);
1917 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1919 * See kern_sigaction() for origin of this code.
1921 SIGDELSET(ps->ps_sigcatch, sig);
1922 if (sig != SIGCONT &&
1923 sigprop(sig) & SA_IGNORE)
1924 SIGADDSET(ps->ps_sigignore, sig);
1925 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1927 mtx_unlock(&ps->ps_mtx);
1930 * Avoid a possible infinite loop if the thread
1931 * masking the signal or process is ignoring the
1934 if (kern_forcesigexit &&
1935 (SIGISMEMBER(td->td_sigmask, sig) ||
1936 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1937 SIGDELSET(td->td_sigmask, sig);
1938 SIGDELSET(ps->ps_sigcatch, sig);
1939 SIGDELSET(ps->ps_sigignore, sig);
1940 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1942 mtx_unlock(&ps->ps_mtx);
1943 p->p_code = code; /* XXX for core dump/debugger */
1944 p->p_sig = sig; /* XXX to verify code */
1945 tdsignal(p, td, sig, ksi);
1950 static struct thread *
1951 sigtd(struct proc *p, int sig, int prop)
1953 struct thread *td, *signal_td;
1955 PROC_LOCK_ASSERT(p, MA_OWNED);
1958 * Check if current thread can handle the signal without
1959 * switching conetxt to another thread.
1961 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1965 FOREACH_THREAD_IN_PROC(p, td) {
1966 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1971 if (signal_td == NULL)
1972 signal_td = FIRST_THREAD_IN_PROC(p);
1978 * Send the signal to the process. If the signal has an action, the action
1979 * is usually performed by the target process rather than the caller; we add
1980 * the signal to the set of pending signals for the process.
1983 * o When a stop signal is sent to a sleeping process that takes the
1984 * default action, the process is stopped without awakening it.
1985 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1986 * regardless of the signal action (eg, blocked or ignored).
1988 * Other ignored signals are discarded immediately.
1990 * NB: This function may be entered from the debugger via the "kill" DDB
1991 * command. There is little that can be done to mitigate the possibly messy
1992 * side effects of this unwise possibility.
1995 psignal(struct proc *p, int sig)
1997 (void) tdsignal(p, NULL, sig, NULL);
2001 psignal_event(struct proc *p, struct sigevent *sigev, ksiginfo_t *ksi)
2003 struct thread *td = NULL;
2005 PROC_LOCK_ASSERT(p, MA_OWNED);
2007 KASSERT(!KSI_ONQ(ksi), ("psignal_event: ksi on queue"));
2010 * ksi_code and other fields should be set before
2011 * calling this function.
2013 ksi->ksi_signo = sigev->sigev_signo;
2014 ksi->ksi_value = sigev->sigev_value;
2015 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2016 td = thread_find(p, sigev->sigev_notify_thread_id);
2020 return (tdsignal(p, td, ksi->ksi_signo, ksi));
2024 tdsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2030 if (p->p_flag & P_SA)
2031 saved = p->p_sigqueue.sq_signals;
2032 ret = do_tdsignal(p, td, sig, ksi);
2033 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) {
2034 if (!SIGSETEQ(saved, p->p_sigqueue.sq_signals)) {
2035 /* pending set changed */
2036 p->p_flag |= P_SIGEVENT;
2037 wakeup(&p->p_siglist);
2044 do_tdsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2048 sigqueue_t *sigqueue;
2054 PROC_LOCK_ASSERT(p, MA_OWNED);
2056 if (!_SIG_VALID(sig))
2058 panic("do_tdsignal(): invalid signal %d", sig);
2060 panic("tdsignal(): invalid signal %d", sig);
2064 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("do_tdsignal: ksi on queue"));
2066 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("tdsignal: ksi on queue"));
2070 * IEEE Std 1003.1-2001: return success when killing a zombie.
2072 if (p->p_state == PRS_ZOMBIE) {
2073 if (ksi && (ksi->ksi_flags & KSI_INS))
2074 ksiginfo_tryfree(ksi);
2079 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2080 prop = sigprop(sig);
2083 * If the signal is blocked and not destined for this thread, then
2084 * assign it to the process so that we can find it later in the first
2085 * thread that unblocks it. Otherwise, assign it to this thread now.
2088 td = sigtd(p, sig, prop);
2089 if (SIGISMEMBER(td->td_sigmask, sig))
2090 sigqueue = &p->p_sigqueue;
2092 sigqueue = &td->td_sigqueue;
2094 KASSERT(td->td_proc == p, ("invalid thread"));
2095 sigqueue = &td->td_sigqueue;
2099 * If the signal is being ignored,
2100 * then we forget about it immediately.
2101 * (Note: we don't set SIGCONT in ps_sigignore,
2102 * and if it is set to SIG_IGN,
2103 * action will be SIG_DFL here.)
2105 mtx_lock(&ps->ps_mtx);
2106 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2107 mtx_unlock(&ps->ps_mtx);
2108 if (ksi && (ksi->ksi_flags & KSI_INS))
2109 ksiginfo_tryfree(ksi);
2112 if (SIGISMEMBER(td->td_sigmask, sig))
2114 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2118 if (SIGISMEMBER(ps->ps_sigintr, sig))
2122 mtx_unlock(&ps->ps_mtx);
2125 sigqueue_delete_stopmask_proc(p);
2126 else if (prop & SA_STOP) {
2128 * If sending a tty stop signal to a member of an orphaned
2129 * process group, discard the signal here if the action
2130 * is default; don't stop the process below if sleeping,
2131 * and don't clear any pending SIGCONT.
2133 if ((prop & SA_TTYSTOP) &&
2134 (p->p_pgrp->pg_jobc == 0) &&
2135 (action == SIG_DFL)) {
2136 if (ksi && (ksi->ksi_flags & KSI_INS))
2137 ksiginfo_tryfree(ksi);
2141 sigqueue_delete_proc(p, SIGCONT);
2143 if (p->p_flag & P_CONTINUED) {
2144 p->p_flag &= ~P_CONTINUED;
2145 PROC_LOCK(p->p_pptr);
2146 sigqueue_take(p->p_ksi);
2147 PROC_UNLOCK(p->p_pptr);
2151 ret = sigqueue_add(sigqueue, sig, ksi);
2156 * Defer further processing for signals which are held,
2157 * except that stopped processes must be continued by SIGCONT.
2159 if (action == SIG_HOLD &&
2160 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2163 * SIGKILL: Remove procfs STOPEVENTs.
2165 if (sig == SIGKILL) {
2166 /* from procfs_ioctl.c: PIOCBIC */
2168 /* from procfs_ioctl.c: PIOCCONT */
2173 * Some signals have a process-wide effect and a per-thread
2174 * component. Most processing occurs when the process next
2175 * tries to cross the user boundary, however there are some
2176 * times when processing needs to be done immediatly, such as
2177 * waking up threads so that they can cross the user boundary.
2178 * We try do the per-process part here.
2181 if (P_SHOULDSTOP(p)) {
2183 * The process is in stopped mode. All the threads should be
2184 * either winding down or already on the suspended queue.
2186 if (p->p_flag & P_TRACED) {
2188 * The traced process is already stopped,
2189 * so no further action is necessary.
2190 * No signal can restart us.
2196 if (sig == SIGKILL) {
2198 * SIGKILL sets process running.
2199 * It will die elsewhere.
2200 * All threads must be restarted.
2202 p->p_flag &= ~P_STOPPED_SIG;
2206 if (prop & SA_CONT) {
2208 * If SIGCONT is default (or ignored), we continue the
2209 * process but don't leave the signal in sigqueue as
2210 * it has no further action. If SIGCONT is held, we
2211 * continue the process and leave the signal in
2212 * sigqueue. If the process catches SIGCONT, let it
2213 * handle the signal itself. If it isn't waiting on
2214 * an event, it goes back to run state.
2215 * Otherwise, process goes back to sleep state.
2217 p->p_flag &= ~P_STOPPED_SIG;
2218 if (p->p_numthreads == p->p_suspcount) {
2220 p->p_flag |= P_CONTINUED;
2221 p->p_xstat = SIGCONT;
2222 PROC_LOCK(p->p_pptr);
2223 childproc_continued(p);
2224 PROC_UNLOCK(p->p_pptr);
2227 if (action == SIG_DFL) {
2228 thread_unsuspend(p);
2230 sigqueue_delete(sigqueue, sig);
2233 if (action == SIG_CATCH) {
2236 * The process wants to catch it so it needs
2237 * to run at least one thread, but which one?
2238 * It would seem that the answer would be to
2239 * run an upcall in the next KSE to run, and
2240 * deliver the signal that way. In a NON KSE
2241 * process, we need to make sure that the
2242 * single thread is runnable asap.
2243 * XXXKSE for now however, make them all run.
2247 * The process wants to catch it so it needs
2248 * to run at least one thread, but which one?
2253 * The signal is not ignored or caught.
2255 thread_unsuspend(p);
2260 if (prop & SA_STOP) {
2262 * Already stopped, don't need to stop again
2263 * (If we did the shell could get confused).
2264 * Just make sure the signal STOP bit set.
2267 p->p_flag |= P_STOPPED_SIG;
2268 sigqueue_delete(sigqueue, sig);
2273 * All other kinds of signals:
2274 * If a thread is sleeping interruptibly, simulate a
2275 * wakeup so that when it is continued it will be made
2276 * runnable and can look at the signal. However, don't make
2277 * the PROCESS runnable, leave it stopped.
2278 * It may run a bit until it hits a thread_suspend_check().
2281 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2282 sleepq_abort(td, intrval);
2287 * Mutexes are short lived. Threads waiting on them will
2288 * hit thread_suspend_check() soon.
2290 } else if (p->p_state == PRS_NORMAL) {
2291 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2293 tdsigwakeup(td, sig, action, intrval);
2299 MPASS(action == SIG_DFL);
2301 if (prop & SA_STOP) {
2302 if (p->p_flag & P_PPWAIT) {
2306 p->p_flag |= P_STOPPED_SIG;
2308 sig_suspend_threads(td, p, 1);
2309 if (p->p_numthreads == p->p_suspcount) {
2311 * only thread sending signal to another
2312 * process can reach here, if thread is sending
2313 * signal to its process, because thread does
2314 * not suspend itself here, p_numthreads
2315 * should never be equal to p_suspcount.
2319 sigqueue_delete_proc(p, p->p_xstat);
2328 /* Not in "NORMAL" state. discard the signal. */
2330 sigqueue_delete(sigqueue, sig);
2335 * The process is not stopped so we need to apply the signal to all the
2341 tdsigwakeup(td, sig, action, intrval);
2343 thread_unsuspend(p);
2346 /* If we jump here, proc slock should not be owned. */
2347 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2352 * The force of a signal has been directed against a single
2353 * thread. We need to see what we can do about knocking it
2354 * out of any sleep it may be in etc.
2357 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2359 struct proc *p = td->td_proc;
2362 PROC_LOCK_ASSERT(p, MA_OWNED);
2363 PROC_SLOCK_ASSERT(p, MA_OWNED);
2364 THREAD_LOCK_ASSERT(td, MA_OWNED);
2365 prop = sigprop(sig);
2368 * Bring the priority of a thread up if we want it to get
2369 * killed in this lifetime.
2371 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2372 sched_prio(td, PUSER);
2374 if (TD_ON_SLEEPQ(td)) {
2376 * If thread is sleeping uninterruptibly
2377 * we can't interrupt the sleep... the signal will
2378 * be noticed when the process returns through
2379 * trap() or syscall().
2381 if ((td->td_flags & TDF_SINTR) == 0)
2384 * If SIGCONT is default (or ignored) and process is
2385 * asleep, we are finished; the process should not
2388 if ((prop & SA_CONT) && action == SIG_DFL) {
2391 sigqueue_delete(&p->p_sigqueue, sig);
2393 * It may be on either list in this state.
2394 * Remove from both for now.
2396 sigqueue_delete(&td->td_sigqueue, sig);
2403 * Give low priority threads a better chance to run.
2405 if (td->td_priority > PUSER)
2406 sched_prio(td, PUSER);
2408 sleepq_abort(td, intrval);
2411 * Other states do nothing with the signal immediately,
2412 * other than kicking ourselves if we are running.
2413 * It will either never be noticed, or noticed very soon.
2416 if (TD_IS_RUNNING(td) && td != curthread)
2423 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2427 PROC_LOCK_ASSERT(p, MA_OWNED);
2428 PROC_SLOCK_ASSERT(p, MA_OWNED);
2430 FOREACH_THREAD_IN_PROC(p, td2) {
2432 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2433 (td2->td_flags & TDF_SINTR) &&
2434 !TD_IS_SUSPENDED(td2)) {
2435 thread_suspend_one(td2);
2437 if (sending || td != td2)
2438 td2->td_flags |= TDF_ASTPENDING;
2440 if (TD_IS_RUNNING(td2) && td2 != td)
2441 forward_signal(td2);
2449 ptracestop(struct thread *td, int sig)
2451 struct proc *p = td->td_proc;
2453 PROC_LOCK_ASSERT(p, MA_OWNED);
2454 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2455 &p->p_mtx.lock_object, "Stopping for traced signal");
2458 td->td_flags |= TDF_XSIG;
2462 while ((p->p_flag & P_TRACED) && (td->td_flags & TDF_XSIG)) {
2463 if (p->p_flag & P_SINGLE_EXIT) {
2465 td->td_flags &= ~TDF_XSIG;
2471 * Just make wait() to work, the last stopped thread
2476 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2477 sig_suspend_threads(td, p, 0);
2479 thread_suspend_switch(td);
2480 if (!(p->p_flag & P_TRACED)) {
2483 if (td->td_flags & TDF_DBSUSPEND) {
2484 if (p->p_flag & P_SINGLE_EXIT)
2490 return (td->td_xsig);
2494 * If the current process has received a signal (should be caught or cause
2495 * termination, should interrupt current syscall), return the signal number.
2496 * Stop signals with default action are processed immediately, then cleared;
2497 * they aren't returned. This is checked after each entry to the system for
2498 * a syscall or trap (though this can usually be done without calling issignal
2499 * by checking the pending signal masks in cursig.) The normal call
2502 * while (sig = cursig(curthread))
2511 sigset_t sigpending;
2512 int sig, prop, newsig;
2516 mtx_assert(&ps->ps_mtx, MA_OWNED);
2517 PROC_LOCK_ASSERT(p, MA_OWNED);
2519 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2521 sigpending = td->td_sigqueue.sq_signals;
2522 SIGSETNAND(sigpending, td->td_sigmask);
2524 if (p->p_flag & P_PPWAIT)
2525 SIG_STOPSIGMASK(sigpending);
2526 if (SIGISEMPTY(sigpending)) /* no signal to send */
2528 sig = sig_ffs(&sigpending);
2530 if (p->p_stops & S_SIG) {
2531 mtx_unlock(&ps->ps_mtx);
2532 stopevent(p, S_SIG, sig);
2533 mtx_lock(&ps->ps_mtx);
2537 * We should see pending but ignored signals
2538 * only if P_TRACED was on when they were posted.
2540 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2541 sigqueue_delete(&td->td_sigqueue, sig);
2543 if (td->td_pflags & TDP_SA)
2544 SIGADDSET(td->td_sigmask, sig);
2548 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
2550 * If traced, always stop.
2552 mtx_unlock(&ps->ps_mtx);
2553 newsig = ptracestop(td, sig);
2554 mtx_lock(&ps->ps_mtx);
2557 if (td->td_pflags & TDP_SA)
2558 SIGADDSET(td->td_sigmask, sig);
2561 if (sig != newsig) {
2565 * XXX shrug off debugger, it causes siginfo to
2568 sigqueue_get(&td->td_sigqueue, sig, &ksi);
2571 * If parent wants us to take the signal,
2572 * then it will leave it in p->p_xstat;
2573 * otherwise we just look for signals again.
2580 * Put the new signal into td_sigqueue. If the
2581 * signal is being masked, look for other signals.
2583 SIGADDSET(td->td_sigqueue.sq_signals, sig);
2585 if (td->td_pflags & TDP_SA)
2586 SIGDELSET(td->td_sigmask, sig);
2588 if (SIGISMEMBER(td->td_sigmask, sig))
2594 * If the traced bit got turned off, go back up
2595 * to the top to rescan signals. This ensures
2596 * that p_sig* and p_sigact are consistent.
2598 if ((p->p_flag & P_TRACED) == 0)
2602 prop = sigprop(sig);
2605 * Decide whether the signal should be returned.
2606 * Return the signal's number, or fall through
2607 * to clear it from the pending mask.
2609 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2611 case (intptr_t)SIG_DFL:
2613 * Don't take default actions on system processes.
2615 if (p->p_pid <= 1) {
2618 * Are you sure you want to ignore SIGSEGV
2621 printf("Process (pid %lu) got signal %d\n",
2622 (u_long)p->p_pid, sig);
2624 break; /* == ignore */
2627 * If there is a pending stop signal to process
2628 * with default action, stop here,
2629 * then clear the signal. However,
2630 * if process is member of an orphaned
2631 * process group, ignore tty stop signals.
2633 if (prop & SA_STOP) {
2634 if (p->p_flag & P_TRACED ||
2635 (p->p_pgrp->pg_jobc == 0 &&
2637 break; /* == ignore */
2638 mtx_unlock(&ps->ps_mtx);
2639 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2640 &p->p_mtx.lock_object, "Catching SIGSTOP");
2641 p->p_flag |= P_STOPPED_SIG;
2644 sig_suspend_threads(td, p, 0);
2645 thread_suspend_switch(td);
2647 mtx_lock(&ps->ps_mtx);
2649 } else if (prop & SA_IGNORE) {
2651 * Except for SIGCONT, shouldn't get here.
2652 * Default action is to ignore; drop it.
2654 break; /* == ignore */
2659 case (intptr_t)SIG_IGN:
2661 * Masking above should prevent us ever trying
2662 * to take action on an ignored signal other
2663 * than SIGCONT, unless process is traced.
2665 if ((prop & SA_CONT) == 0 &&
2666 (p->p_flag & P_TRACED) == 0)
2667 printf("issignal\n");
2668 break; /* == ignore */
2672 * This signal has an action, let
2673 * postsig() process it.
2677 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2683 thread_stopped(struct proc *p)
2687 PROC_LOCK_ASSERT(p, MA_OWNED);
2688 PROC_SLOCK_ASSERT(p, MA_OWNED);
2692 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2694 p->p_flag &= ~P_WAITED;
2695 PROC_LOCK(p->p_pptr);
2696 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2697 CLD_TRAPPED : CLD_STOPPED);
2698 PROC_UNLOCK(p->p_pptr);
2704 * Take the action for the specified signal
2705 * from the current set of pending signals.
2711 struct thread *td = curthread;
2712 register struct proc *p = td->td_proc;
2716 sigset_t returnmask;
2719 KASSERT(sig != 0, ("postsig"));
2721 PROC_LOCK_ASSERT(p, MA_OWNED);
2723 mtx_assert(&ps->ps_mtx, MA_OWNED);
2724 ksiginfo_init(&ksi);
2725 sigqueue_get(&td->td_sigqueue, sig, &ksi);
2726 ksi.ksi_signo = sig;
2727 if (ksi.ksi_code == SI_TIMER)
2728 itimer_accept(p, ksi.ksi_timerid, &ksi);
2729 action = ps->ps_sigact[_SIG_IDX(sig)];
2731 if (KTRPOINT(td, KTR_PSIG))
2732 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2733 &td->td_oldsigmask : &td->td_sigmask, 0);
2735 if (p->p_stops & S_SIG) {
2736 mtx_unlock(&ps->ps_mtx);
2737 stopevent(p, S_SIG, sig);
2738 mtx_lock(&ps->ps_mtx);
2742 if (!(td->td_pflags & TDP_SA) && action == SIG_DFL) {
2744 if (action == SIG_DFL) {
2747 * Default action, where the default is to kill
2748 * the process. (Other cases were ignored above.)
2750 mtx_unlock(&ps->ps_mtx);
2755 if (td->td_pflags & TDP_SA) {
2756 if (sig == SIGKILL) {
2757 mtx_unlock(&ps->ps_mtx);
2764 * If we get here, the signal must be caught.
2766 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2767 ("postsig action"));
2769 * Set the new mask value and also defer further
2770 * occurrences of this signal.
2772 * Special case: user has done a sigsuspend. Here the
2773 * current mask is not of interest, but rather the
2774 * mask from before the sigsuspend is what we want
2775 * restored after the signal processing is completed.
2777 if (td->td_pflags & TDP_OLDMASK) {
2778 returnmask = td->td_oldsigmask;
2779 td->td_pflags &= ~TDP_OLDMASK;
2781 returnmask = td->td_sigmask;
2783 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
2784 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2785 SIGADDSET(td->td_sigmask, sig);
2787 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2789 * See kern_sigaction() for origin of this code.
2791 SIGDELSET(ps->ps_sigcatch, sig);
2792 if (sig != SIGCONT &&
2793 sigprop(sig) & SA_IGNORE)
2794 SIGADDSET(ps->ps_sigignore, sig);
2795 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2797 td->td_ru.ru_nsignals++;
2798 if (p->p_sig != sig) {
2806 if (td->td_pflags & TDP_SA)
2807 thread_signal_add(curthread, &ksi);
2809 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2811 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2817 * Kill the current process for stated reason.
2825 PROC_LOCK_ASSERT(p, MA_OWNED);
2826 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)",
2827 p, p->p_pid, p->p_comm);
2828 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
2829 p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2830 psignal(p, SIGKILL);
2834 * Force the current process to exit with the specified signal, dumping core
2835 * if appropriate. We bypass the normal tests for masked and caught signals,
2836 * allowing unrecoverable failures to terminate the process without changing
2837 * signal state. Mark the accounting record with the signal termination.
2838 * If dumping core, save the signal number for the debugger. Calls exit and
2846 struct proc *p = td->td_proc;
2848 PROC_LOCK_ASSERT(p, MA_OWNED);
2849 p->p_acflag |= AXSIG;
2851 * We must be single-threading to generate a core dump. This
2852 * ensures that the registers in the core file are up-to-date.
2853 * Also, the ELF dump handler assumes that the thread list doesn't
2854 * change out from under it.
2856 * XXX If another thread attempts to single-thread before us
2857 * (e.g. via fork()), we won't get a dump at all.
2859 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2862 * Log signals which would cause core dumps
2863 * (Log as LOG_INFO to appease those who don't want
2865 * XXX : Todo, as well as euid, write out ruid too
2866 * Note that coredump() drops proc lock.
2868 if (coredump(td) == 0)
2870 if (kern_logsigexit)
2872 "pid %d (%s), uid %d: exited on signal %d%s\n",
2873 p->p_pid, p->p_comm,
2874 td->td_ucred ? td->td_ucred->cr_uid : -1,
2876 sig & WCOREFLAG ? " (core dumped)" : "");
2879 exit1(td, W_EXITCODE(0, sig));
2884 * Send queued SIGCHLD to parent when child process's state
2888 sigparent(struct proc *p, int reason, int status)
2890 PROC_LOCK_ASSERT(p, MA_OWNED);
2891 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2893 if (p->p_ksi != NULL) {
2894 p->p_ksi->ksi_signo = SIGCHLD;
2895 p->p_ksi->ksi_code = reason;
2896 p->p_ksi->ksi_status = status;
2897 p->p_ksi->ksi_pid = p->p_pid;
2898 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2899 if (KSI_ONQ(p->p_ksi))
2902 tdsignal(p->p_pptr, NULL, SIGCHLD, p->p_ksi);
2906 childproc_jobstate(struct proc *p, int reason, int status)
2910 PROC_LOCK_ASSERT(p, MA_OWNED);
2911 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2914 * Wake up parent sleeping in kern_wait(), also send
2915 * SIGCHLD to parent, but SIGCHLD does not guarantee
2916 * that parent will awake, because parent may masked
2919 p->p_pptr->p_flag |= P_STATCHILD;
2922 ps = p->p_pptr->p_sigacts;
2923 mtx_lock(&ps->ps_mtx);
2924 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2925 mtx_unlock(&ps->ps_mtx);
2926 sigparent(p, reason, status);
2928 mtx_unlock(&ps->ps_mtx);
2932 childproc_stopped(struct proc *p, int reason)
2934 childproc_jobstate(p, reason, p->p_xstat);
2938 childproc_continued(struct proc *p)
2940 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
2944 childproc_exited(struct proc *p)
2947 int status = p->p_xstat; /* convert to int */
2949 reason = CLD_EXITED;
2950 if (WCOREDUMP(status))
2951 reason = CLD_DUMPED;
2952 else if (WIFSIGNALED(status))
2953 reason = CLD_KILLED;
2955 * XXX avoid calling wakeup(p->p_pptr), the work is
2958 sigparent(p, reason, status);
2961 static char corefilename[MAXPATHLEN] = {"%N.core"};
2962 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
2963 sizeof(corefilename), "process corefile name format string");
2966 * expand_name(name, uid, pid)
2967 * Expand the name described in corefilename, using name, uid, and pid.
2968 * corefilename is a printf-like string, with three format specifiers:
2969 * %N name of process ("name")
2970 * %P process id (pid)
2972 * For example, "%N.core" is the default; they can be disabled completely
2973 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
2974 * This is controlled by the sysctl variable kern.corefile (see above).
2978 expand_name(name, uid, pid)
2983 const char *format, *appendstr;
2985 char buf[11]; /* Buffer for pid/uid -- max 4B */
2988 format = corefilename;
2989 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
2992 for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) {
2993 switch (format[i]) {
2994 case '%': /* Format character */
2996 switch (format[i]) {
3000 case 'N': /* process name */
3003 case 'P': /* process id */
3004 sprintf(buf, "%u", pid);
3007 case 'U': /* user id */
3008 sprintf(buf, "%u", uid);
3014 "Unknown format character %c in `%s'\n",
3017 l = strlen(appendstr);
3018 if ((n + l) >= MAXPATHLEN)
3020 memcpy(temp + n, appendstr, l);
3024 temp[n++] = format[i];
3027 if (format[i] != '\0')
3031 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too long\n",
3032 (long)pid, name, (u_long)uid);
3038 * Dump a process' core. The main routine does some
3039 * policy checking, and creates the name of the coredump;
3040 * then it passes on a vnode and a size limit to the process-specific
3041 * coredump routine if there is one; if there _is not_ one, it returns
3042 * ENOSYS; otherwise it returns the error from the process-specific routine.
3046 coredump(struct thread *td)
3048 struct proc *p = td->td_proc;
3049 register struct vnode *vp;
3050 register struct ucred *cred = td->td_ucred;
3052 struct nameidata nd;
3054 int error, error1, flags, locked;
3056 char *name; /* name of corefile */
3060 PROC_LOCK_ASSERT(p, MA_OWNED);
3061 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3062 _STOPEVENT(p, S_CORE, 0);
3064 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid);
3067 audit_proc_coredump(td, NULL, EINVAL);
3071 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) {
3074 audit_proc_coredump(td, name, EFAULT);
3081 * Note that the bulk of limit checking is done after
3082 * the corefile is created. The exception is if the limit
3083 * for corefiles is 0, in which case we don't bother
3084 * creating the corefile at all. This layout means that
3085 * a corefile is truncated instead of not being created,
3086 * if it is larger than the limit.
3088 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3092 audit_proc_coredump(td, name, EFBIG);
3099 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, name, td);
3100 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3101 error = vn_open(&nd, &flags, S_IRUSR | S_IWUSR, NULL);
3104 audit_proc_coredump(td, name, error);
3109 vfslocked = NDHASGIANT(&nd);
3110 NDFREE(&nd, NDF_ONLY_PNBUF);
3113 /* Don't dump to non-regular files or files with links. */
3114 if (vp->v_type != VREG ||
3115 VOP_GETATTR(vp, &vattr, cred, td) || vattr.va_nlink != 1) {
3116 VOP_UNLOCK(vp, 0, td);
3121 VOP_UNLOCK(vp, 0, td);
3122 lf.l_whence = SEEK_SET;
3125 lf.l_type = F_WRLCK;
3126 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3128 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3129 lf.l_type = F_UNLCK;
3131 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3132 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3134 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3136 VFS_UNLOCK_GIANT(vfslocked);
3142 if (set_core_nodump_flag)
3143 vattr.va_flags = UF_NODUMP;
3144 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3145 VOP_LEASE(vp, td, cred, LEASE_WRITE);
3146 VOP_SETATTR(vp, &vattr, cred, td);
3147 VOP_UNLOCK(vp, 0, td);
3148 vn_finished_write(mp);
3150 p->p_acflag |= ACORE;
3153 error = p->p_sysent->sv_coredump ?
3154 p->p_sysent->sv_coredump(td, vp, limit) :
3158 lf.l_type = F_UNLCK;
3159 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3162 error1 = vn_close(vp, FWRITE, cred, td);
3167 audit_proc_coredump(td, name, error);
3170 VFS_UNLOCK_GIANT(vfslocked);
3175 * Nonexistent system call-- signal process (may want to handle it). Flag
3176 * error in case process won't see signal immediately (blocked or ignored).
3178 #ifndef _SYS_SYSPROTO_H_
3187 struct nosys_args *args;
3189 struct proc *p = td->td_proc;
3198 * Send a SIGIO or SIGURG signal to a process or process group using stored
3199 * credentials rather than those of the current process.
3202 pgsigio(sigiop, sig, checkctty)
3203 struct sigio **sigiop;
3206 struct sigio *sigio;
3210 if (sigio == NULL) {
3214 if (sigio->sio_pgid > 0) {
3215 PROC_LOCK(sigio->sio_proc);
3216 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3217 psignal(sigio->sio_proc, sig);
3218 PROC_UNLOCK(sigio->sio_proc);
3219 } else if (sigio->sio_pgid < 0) {
3222 PGRP_LOCK(sigio->sio_pgrp);
3223 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3225 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3226 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3230 PGRP_UNLOCK(sigio->sio_pgrp);
3236 filt_sigattach(struct knote *kn)
3238 struct proc *p = curproc;
3240 kn->kn_ptr.p_proc = p;
3241 kn->kn_flags |= EV_CLEAR; /* automatically set */
3243 knlist_add(&p->p_klist, kn, 0);
3249 filt_sigdetach(struct knote *kn)
3251 struct proc *p = kn->kn_ptr.p_proc;
3253 knlist_remove(&p->p_klist, kn, 0);
3257 * signal knotes are shared with proc knotes, so we apply a mask to
3258 * the hint in order to differentiate them from process hints. This
3259 * could be avoided by using a signal-specific knote list, but probably
3260 * isn't worth the trouble.
3263 filt_signal(struct knote *kn, long hint)
3266 if (hint & NOTE_SIGNAL) {
3267 hint &= ~NOTE_SIGNAL;
3269 if (kn->kn_id == hint)
3272 return (kn->kn_data != 0);
3280 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3282 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3287 sigacts_free(struct sigacts *ps)
3290 mtx_lock(&ps->ps_mtx);
3292 if (ps->ps_refcnt == 0) {
3293 mtx_destroy(&ps->ps_mtx);
3294 free(ps, M_SUBPROC);
3296 mtx_unlock(&ps->ps_mtx);
3300 sigacts_hold(struct sigacts *ps)
3302 mtx_lock(&ps->ps_mtx);
3304 mtx_unlock(&ps->ps_mtx);
3309 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3312 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3313 mtx_lock(&src->ps_mtx);
3314 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3315 mtx_unlock(&src->ps_mtx);
3319 sigacts_shared(struct sigacts *ps)
3323 mtx_lock(&ps->ps_mtx);
3324 shared = ps->ps_refcnt > 1;
3325 mtx_unlock(&ps->ps_mtx);