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
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14 * notice, this list of conditions and the following disclaimer.
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34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
41 #include "opt_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 static 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)
294 SIGDELSET(sq->sq_signals, signo);
295 si->ksi_signo = signo;
300 sigqueue_take(ksiginfo_t *ksi)
306 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
310 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
311 ksi->ksi_sigq = NULL;
312 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
315 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
316 kp = TAILQ_NEXT(kp, ksi_link)) {
317 if (kp->ksi_signo == ksi->ksi_signo)
320 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
321 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
325 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
327 struct proc *p = sq->sq_proc;
328 struct ksiginfo *ksi;
331 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
333 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
334 SIGADDSET(sq->sq_kill, signo);
338 /* directly insert the ksi, don't copy it */
339 if (si->ksi_flags & KSI_INS) {
340 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
345 if (__predict_false(ksiginfo_zone == NULL)) {
346 SIGADDSET(sq->sq_kill, signo);
350 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
353 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
359 ksiginfo_copy(si, ksi);
360 ksi->ksi_signo = signo;
361 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
365 if ((si->ksi_flags & KSI_TRAP) != 0) {
367 SIGADDSET(sq->sq_kill, signo);
376 SIGADDSET(sq->sq_signals, signo);
381 sigqueue_flush(sigqueue_t *sq)
383 struct proc *p = sq->sq_proc;
386 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
389 PROC_LOCK_ASSERT(p, MA_OWNED);
391 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
392 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
393 ksi->ksi_sigq = NULL;
394 if (ksiginfo_tryfree(ksi) && p != NULL)
398 SIGEMPTYSET(sq->sq_signals);
399 SIGEMPTYSET(sq->sq_kill);
403 sigqueue_collect_set(sigqueue_t *sq, sigset_t *set)
407 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
409 TAILQ_FOREACH(ksi, &sq->sq_list, ksi_link)
410 SIGADDSET(*set, ksi->ksi_signo);
411 SIGSETOR(*set, sq->sq_kill);
415 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, sigset_t *setp)
418 struct proc *p1, *p2;
419 ksiginfo_t *ksi, *next;
421 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
422 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
424 * make a copy, this allows setp to point to src or dst
425 * sq_signals without trouble.
430 /* Move siginfo to target list */
431 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
432 if (SIGISMEMBER(set, ksi->ksi_signo)) {
433 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
436 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
443 /* Move pending bits to target list */
446 SIGSETOR(dst->sq_kill, tmp);
447 SIGSETNAND(src->sq_kill, tmp);
449 tmp = src->sq_signals;
451 SIGSETOR(dst->sq_signals, tmp);
452 SIGSETNAND(src->sq_signals, tmp);
454 /* Finally, rescan src queue and set pending bits for it */
455 sigqueue_collect_set(src, &src->sq_signals);
459 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
464 SIGADDSET(set, signo);
465 sigqueue_move_set(src, dst, &set);
469 sigqueue_delete_set(sigqueue_t *sq, sigset_t *set)
471 struct proc *p = sq->sq_proc;
472 ksiginfo_t *ksi, *next;
474 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
476 /* Remove siginfo queue */
477 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
478 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
479 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
480 ksi->ksi_sigq = NULL;
481 if (ksiginfo_tryfree(ksi) && p != NULL)
485 SIGSETNAND(sq->sq_kill, *set);
486 SIGSETNAND(sq->sq_signals, *set);
487 /* Finally, rescan queue and set pending bits for it */
488 sigqueue_collect_set(sq, &sq->sq_signals);
492 sigqueue_delete(sigqueue_t *sq, int signo)
497 SIGADDSET(set, signo);
498 sigqueue_delete_set(sq, &set);
501 /* Remove a set of signals for a process */
503 sigqueue_delete_set_proc(struct proc *p, sigset_t *set)
508 PROC_LOCK_ASSERT(p, MA_OWNED);
510 sigqueue_init(&worklist, NULL);
511 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
513 mtx_lock_spin(&sched_lock);
514 FOREACH_THREAD_IN_PROC(p, td0)
515 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
516 mtx_unlock_spin(&sched_lock);
518 sigqueue_flush(&worklist);
522 sigqueue_delete_proc(struct proc *p, int signo)
527 SIGADDSET(set, signo);
528 sigqueue_delete_set_proc(p, &set);
532 sigqueue_delete_stopmask_proc(struct proc *p)
537 SIGADDSET(set, SIGSTOP);
538 SIGADDSET(set, SIGTSTP);
539 SIGADDSET(set, SIGTTIN);
540 SIGADDSET(set, SIGTTOU);
541 sigqueue_delete_set_proc(p, &set);
545 * Determine signal that should be delivered to process p, the current
546 * process, 0 if none. If there is a pending stop signal with default
547 * action, the process stops in issignal().
552 cursig(struct thread *td)
554 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
555 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
556 mtx_assert(&sched_lock, MA_NOTOWNED);
557 return (SIGPENDING(td) ? issignal(td) : 0);
561 * Arrange for ast() to handle unmasked pending signals on return to user
562 * mode. This must be called whenever a signal is added to td_sigqueue or
563 * unmasked in td_sigmask.
566 signotify(struct thread *td)
577 PROC_LOCK_ASSERT(p, MA_OWNED);
580 * If our mask changed we may have to move signal that were
581 * previously masked by all threads to our sigqueue.
583 set = p->p_sigqueue.sq_signals;
585 if (p->p_flag & P_SA)
586 saved = p->p_sigqueue.sq_signals;
588 SIGSETNAND(set, td->td_sigmask);
589 if (! SIGISEMPTY(set))
590 sigqueue_move_set(&p->p_sigqueue, &td->td_sigqueue, &set);
591 if (SIGPENDING(td)) {
592 mtx_lock_spin(&sched_lock);
593 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
594 mtx_unlock_spin(&sched_lock);
597 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) {
598 if (!SIGSETEQ(saved, p->p_sigqueue.sq_signals)) {
599 /* pending set changed */
600 p->p_flag |= P_SIGEVENT;
601 wakeup(&p->p_siglist);
608 sigonstack(size_t sp)
610 struct thread *td = curthread;
612 return ((td->td_pflags & TDP_ALTSTACK) ?
613 #if defined(COMPAT_43)
614 ((td->td_sigstk.ss_size == 0) ?
615 (td->td_sigstk.ss_flags & SS_ONSTACK) :
616 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
618 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
627 if (sig > 0 && sig < NSIG)
628 return (sigproptbl[_SIG_IDX(sig)]);
633 sig_ffs(sigset_t *set)
637 for (i = 0; i < _SIG_WORDS; i++)
639 return (ffs(set->__bits[i]) + (i * 32));
652 kern_sigaction(td, sig, act, oact, flags)
655 struct sigaction *act, *oact;
659 struct proc *p = td->td_proc;
661 if (!_SIG_VALID(sig))
666 mtx_lock(&ps->ps_mtx);
668 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
669 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
671 if (SIGISMEMBER(ps->ps_sigonstack, sig))
672 oact->sa_flags |= SA_ONSTACK;
673 if (!SIGISMEMBER(ps->ps_sigintr, sig))
674 oact->sa_flags |= SA_RESTART;
675 if (SIGISMEMBER(ps->ps_sigreset, sig))
676 oact->sa_flags |= SA_RESETHAND;
677 if (SIGISMEMBER(ps->ps_signodefer, sig))
678 oact->sa_flags |= SA_NODEFER;
679 if (SIGISMEMBER(ps->ps_siginfo, sig))
680 oact->sa_flags |= SA_SIGINFO;
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 */
764 sigqueue_delete_proc(p, sig);
766 /* easier in psignal */
767 SIGADDSET(ps->ps_sigignore, sig);
768 SIGDELSET(ps->ps_sigcatch, sig);
770 SIGDELSET(ps->ps_sigignore, sig);
771 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
772 SIGDELSET(ps->ps_sigcatch, sig);
774 SIGADDSET(ps->ps_sigcatch, sig);
776 #ifdef COMPAT_FREEBSD4
777 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
778 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
779 (flags & KSA_FREEBSD4) == 0)
780 SIGDELSET(ps->ps_freebsd4, sig);
782 SIGADDSET(ps->ps_freebsd4, sig);
785 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
786 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
787 (flags & KSA_OSIGSET) == 0)
788 SIGDELSET(ps->ps_osigset, sig);
790 SIGADDSET(ps->ps_osigset, sig);
793 mtx_unlock(&ps->ps_mtx);
798 #ifndef _SYS_SYSPROTO_H_
799 struct sigaction_args {
801 struct sigaction *act;
802 struct sigaction *oact;
811 register struct sigaction_args *uap;
813 struct sigaction act, oact;
814 register struct sigaction *actp, *oactp;
817 actp = (uap->act != NULL) ? &act : NULL;
818 oactp = (uap->oact != NULL) ? &oact : NULL;
820 error = copyin(uap->act, actp, sizeof(act));
824 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
826 error = copyout(oactp, uap->oact, sizeof(oact));
830 #ifdef COMPAT_FREEBSD4
831 #ifndef _SYS_SYSPROTO_H_
832 struct freebsd4_sigaction_args {
834 struct sigaction *act;
835 struct sigaction *oact;
842 freebsd4_sigaction(td, uap)
844 register struct freebsd4_sigaction_args *uap;
846 struct sigaction act, oact;
847 register struct sigaction *actp, *oactp;
851 actp = (uap->act != NULL) ? &act : NULL;
852 oactp = (uap->oact != NULL) ? &oact : NULL;
854 error = copyin(uap->act, actp, sizeof(act));
858 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
860 error = copyout(oactp, uap->oact, sizeof(oact));
863 #endif /* COMAPT_FREEBSD4 */
865 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
866 #ifndef _SYS_SYSPROTO_H_
867 struct osigaction_args {
869 struct osigaction *nsa;
870 struct osigaction *osa;
879 register struct osigaction_args *uap;
881 struct osigaction sa;
882 struct sigaction nsa, osa;
883 register struct sigaction *nsap, *osap;
886 if (uap->signum <= 0 || uap->signum >= ONSIG)
889 nsap = (uap->nsa != NULL) ? &nsa : NULL;
890 osap = (uap->osa != NULL) ? &osa : NULL;
893 error = copyin(uap->nsa, &sa, sizeof(sa));
896 nsap->sa_handler = sa.sa_handler;
897 nsap->sa_flags = sa.sa_flags;
898 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
900 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
901 if (osap && !error) {
902 sa.sa_handler = osap->sa_handler;
903 sa.sa_flags = osap->sa_flags;
904 SIG2OSIG(osap->sa_mask, sa.sa_mask);
905 error = copyout(&sa, uap->osa, sizeof(sa));
910 #if !defined(__i386__)
911 /* Avoid replicating the same stub everywhere */
915 struct osigreturn_args *uap;
918 return (nosys(td, (struct nosys_args *)uap));
921 #endif /* COMPAT_43 */
924 * Initialize signal state for process 0;
925 * set to ignore signals that are ignored by default.
936 mtx_lock(&ps->ps_mtx);
937 for (i = 1; i <= NSIG; i++)
938 if (sigprop(i) & SA_IGNORE && i != SIGCONT)
939 SIGADDSET(ps->ps_sigignore, i);
940 mtx_unlock(&ps->ps_mtx);
945 * Reset signals for an exec of the specified process.
948 execsigs(struct proc *p)
955 * Reset caught signals. Held signals remain held
956 * through td_sigmask (unless they were caught,
957 * and are now ignored by default).
959 PROC_LOCK_ASSERT(p, MA_OWNED);
960 td = FIRST_THREAD_IN_PROC(p);
962 mtx_lock(&ps->ps_mtx);
963 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
964 sig = sig_ffs(&ps->ps_sigcatch);
965 SIGDELSET(ps->ps_sigcatch, sig);
966 if (sigprop(sig) & SA_IGNORE) {
968 SIGADDSET(ps->ps_sigignore, sig);
969 sigqueue_delete_proc(p, sig);
971 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
974 * Reset stack state to the user stack.
975 * Clear set of signals caught on the signal stack.
977 td->td_sigstk.ss_flags = SS_DISABLE;
978 td->td_sigstk.ss_size = 0;
979 td->td_sigstk.ss_sp = 0;
980 td->td_pflags &= ~TDP_ALTSTACK;
982 * Reset no zombies if child dies flag as Solaris does.
984 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
985 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
986 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
987 mtx_unlock(&ps->ps_mtx);
993 * Manipulate signal mask.
996 kern_sigprocmask(td, how, set, oset, old)
999 sigset_t *set, *oset;
1004 PROC_LOCK(td->td_proc);
1006 *oset = td->td_sigmask;
1013 SIGSETOR(td->td_sigmask, *set);
1016 SIGSETNAND(td->td_sigmask, *set);
1022 SIGSETLO(td->td_sigmask, *set);
1024 td->td_sigmask = *set;
1032 PROC_UNLOCK(td->td_proc);
1037 * sigprocmask() - MP SAFE
1040 #ifndef _SYS_SYSPROTO_H_
1041 struct sigprocmask_args {
1043 const sigset_t *set;
1048 sigprocmask(td, uap)
1049 register struct thread *td;
1050 struct sigprocmask_args *uap;
1053 sigset_t *setp, *osetp;
1056 setp = (uap->set != NULL) ? &set : NULL;
1057 osetp = (uap->oset != NULL) ? &oset : NULL;
1059 error = copyin(uap->set, setp, sizeof(set));
1063 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1064 if (osetp && !error) {
1065 error = copyout(osetp, uap->oset, sizeof(oset));
1070 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1072 * osigprocmask() - MP SAFE
1074 #ifndef _SYS_SYSPROTO_H_
1075 struct osigprocmask_args {
1081 osigprocmask(td, uap)
1082 register struct thread *td;
1083 struct osigprocmask_args *uap;
1088 OSIG2SIG(uap->mask, set);
1089 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1090 SIG2OSIG(oset, td->td_retval[0]);
1093 #endif /* COMPAT_43 */
1099 sigwait(struct thread *td, struct sigwait_args *uap)
1105 error = copyin(uap->set, &set, sizeof(set));
1107 td->td_retval[0] = error;
1111 error = kern_sigtimedwait(td, set, &ksi, NULL);
1113 if (error == ERESTART)
1115 td->td_retval[0] = error;
1119 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1120 td->td_retval[0] = error;
1127 sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1130 struct timespec *timeout;
1136 error = copyin(uap->timeout, &ts, sizeof(ts));
1144 error = copyin(uap->set, &set, sizeof(set));
1148 error = kern_sigtimedwait(td, set, &ksi, timeout);
1153 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1156 td->td_retval[0] = ksi.ksi_signo;
1164 sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1170 error = copyin(uap->set, &set, sizeof(set));
1174 error = kern_sigtimedwait(td, set, &ksi, NULL);
1179 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1182 td->td_retval[0] = ksi.ksi_signo;
1187 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1188 struct timespec *timeout)
1193 int error, sig, hz, i, timevalid = 0;
1194 struct timespec rts, ets, ts;
1200 SIG_CANTMASK(waitset);
1204 savedmask = td->td_sigmask;
1206 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1208 getnanouptime(&rts);
1210 timespecadd(&ets, timeout);
1215 for (i = 1; i <= _SIG_MAXSIG; ++i) {
1216 if (!SIGISMEMBER(waitset, i))
1218 if (!SIGISMEMBER(td->td_sigqueue.sq_signals, i)) {
1219 if (SIGISMEMBER(p->p_sigqueue.sq_signals, i)) {
1221 if (p->p_flag & P_SA) {
1222 p->p_flag |= P_SIGEVENT;
1223 wakeup(&p->p_siglist);
1226 sigqueue_move(&p->p_sigqueue,
1227 &td->td_sigqueue, i);
1232 SIGFILLSET(td->td_sigmask);
1233 SIG_CANTMASK(td->td_sigmask);
1234 SIGDELSET(td->td_sigmask, i);
1235 mtx_lock(&ps->ps_mtx);
1237 mtx_unlock(&ps->ps_mtx);
1242 * Because cursig() may have stopped current thread,
1243 * after it is resumed, things may have already been
1244 * changed, it should rescan any pending signals.
1254 * POSIX says this must be checked after looking for pending
1262 getnanouptime(&rts);
1263 if (timespeccmp(&rts, &ets, >=)) {
1268 timespecsub(&ts, &rts);
1269 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1274 td->td_sigmask = savedmask;
1275 SIGSETNAND(td->td_sigmask, waitset);
1277 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz);
1279 if (error == ERESTART) {
1280 /* timeout can not be restarted. */
1282 } else if (error == EAGAIN) {
1283 /* will calculate timeout by ourself. */
1290 td->td_sigmask = savedmask;
1294 sigqueue_get(&td->td_sigqueue, sig, ksi);
1295 ksi->ksi_signo = sig;
1296 if (ksi->ksi_code == SI_TIMER)
1297 itimer_accept(p, ksi->ksi_timerid, ksi);
1301 if (KTRPOINT(td, KTR_PSIG)) {
1304 mtx_lock(&ps->ps_mtx);
1305 action = ps->ps_sigact[_SIG_IDX(sig)];
1306 mtx_unlock(&ps->ps_mtx);
1307 ktrpsig(sig, action, &td->td_sigmask, 0);
1317 #ifndef _SYS_SYSPROTO_H_
1318 struct sigpending_args {
1328 struct sigpending_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 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1340 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1341 #ifndef _SYS_SYSPROTO_H_
1342 struct osigpending_args {
1350 osigpending(td, uap)
1352 struct osigpending_args *uap;
1354 struct proc *p = td->td_proc;
1358 pending = p->p_sigqueue.sq_signals;
1359 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1361 SIG2OSIG(pending, td->td_retval[0]);
1364 #endif /* COMPAT_43 */
1366 #if defined(COMPAT_43)
1368 * Generalized interface signal handler, 4.3-compatible.
1370 #ifndef _SYS_SYSPROTO_H_
1371 struct osigvec_args {
1384 register struct osigvec_args *uap;
1387 struct sigaction nsa, osa;
1388 register struct sigaction *nsap, *osap;
1391 if (uap->signum <= 0 || uap->signum >= ONSIG)
1393 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1394 osap = (uap->osv != NULL) ? &osa : NULL;
1396 error = copyin(uap->nsv, &vec, sizeof(vec));
1399 nsap->sa_handler = vec.sv_handler;
1400 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1401 nsap->sa_flags = vec.sv_flags;
1402 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1404 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1405 if (osap && !error) {
1406 vec.sv_handler = osap->sa_handler;
1407 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1408 vec.sv_flags = osap->sa_flags;
1409 vec.sv_flags &= ~SA_NOCLDWAIT;
1410 vec.sv_flags ^= SA_RESTART;
1411 error = copyout(&vec, uap->osv, sizeof(vec));
1416 #ifndef _SYS_SYSPROTO_H_
1417 struct osigblock_args {
1426 register struct thread *td;
1427 struct osigblock_args *uap;
1429 struct proc *p = td->td_proc;
1432 OSIG2SIG(uap->mask, set);
1435 SIG2OSIG(td->td_sigmask, td->td_retval[0]);
1436 SIGSETOR(td->td_sigmask, set);
1441 #ifndef _SYS_SYSPROTO_H_
1442 struct osigsetmask_args {
1450 osigsetmask(td, uap)
1452 struct osigsetmask_args *uap;
1454 struct proc *p = td->td_proc;
1457 OSIG2SIG(uap->mask, set);
1460 SIG2OSIG(td->td_sigmask, td->td_retval[0]);
1461 SIGSETLO(td->td_sigmask, set);
1466 #endif /* COMPAT_43 */
1469 * Suspend calling thread until signal, providing mask to be set
1472 #ifndef _SYS_SYSPROTO_H_
1473 struct sigsuspend_args {
1474 const sigset_t *sigmask;
1484 struct sigsuspend_args *uap;
1489 error = copyin(uap->sigmask, &mask, sizeof(mask));
1492 return (kern_sigsuspend(td, mask));
1496 kern_sigsuspend(struct thread *td, sigset_t mask)
1498 struct proc *p = td->td_proc;
1501 * When returning from sigsuspend, we want
1502 * the old mask to be restored after the
1503 * signal handler has finished. Thus, we
1504 * save it here and mark the sigacts structure
1508 td->td_oldsigmask = td->td_sigmask;
1509 td->td_pflags |= TDP_OLDMASK;
1511 td->td_sigmask = mask;
1513 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0)
1516 /* always return EINTR rather than ERESTART... */
1520 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1522 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1523 * convention: libc stub passes mask, not pointer, to save a copyin.
1525 #ifndef _SYS_SYSPROTO_H_
1526 struct osigsuspend_args {
1535 osigsuspend(td, uap)
1537 struct osigsuspend_args *uap;
1539 struct proc *p = td->td_proc;
1543 td->td_oldsigmask = td->td_sigmask;
1544 td->td_pflags |= TDP_OLDMASK;
1545 OSIG2SIG(uap->mask, mask);
1547 SIGSETLO(td->td_sigmask, mask);
1549 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0)
1552 /* always return EINTR rather than ERESTART... */
1555 #endif /* COMPAT_43 */
1557 #if defined(COMPAT_43)
1558 #ifndef _SYS_SYSPROTO_H_
1559 struct osigstack_args {
1560 struct sigstack *nss;
1561 struct sigstack *oss;
1571 register struct osigstack_args *uap;
1573 struct sigstack nss, oss;
1576 if (uap->nss != NULL) {
1577 error = copyin(uap->nss, &nss, sizeof(nss));
1581 oss.ss_sp = td->td_sigstk.ss_sp;
1582 oss.ss_onstack = sigonstack(cpu_getstack(td));
1583 if (uap->nss != NULL) {
1584 td->td_sigstk.ss_sp = nss.ss_sp;
1585 td->td_sigstk.ss_size = 0;
1586 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1587 td->td_pflags |= TDP_ALTSTACK;
1589 if (uap->oss != NULL)
1590 error = copyout(&oss, uap->oss, sizeof(oss));
1594 #endif /* COMPAT_43 */
1596 #ifndef _SYS_SYSPROTO_H_
1597 struct sigaltstack_args {
1607 sigaltstack(td, uap)
1609 register struct sigaltstack_args *uap;
1614 if (uap->ss != NULL) {
1615 error = copyin(uap->ss, &ss, sizeof(ss));
1619 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1620 (uap->oss != NULL) ? &oss : NULL);
1623 if (uap->oss != NULL)
1624 error = copyout(&oss, uap->oss, sizeof(stack_t));
1629 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1631 struct proc *p = td->td_proc;
1634 oonstack = sigonstack(cpu_getstack(td));
1637 *oss = td->td_sigstk;
1638 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1639 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1645 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1647 if (!(ss->ss_flags & SS_DISABLE)) {
1648 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1651 td->td_sigstk = *ss;
1652 td->td_pflags |= TDP_ALTSTACK;
1654 td->td_pflags &= ~TDP_ALTSTACK;
1661 * Common code for kill process group/broadcast kill.
1662 * cp is calling process.
1665 killpg1(td, sig, pgid, all)
1666 register struct thread *td;
1669 register struct proc *p;
1677 sx_slock(&allproc_lock);
1678 LIST_FOREACH(p, &allproc, p_list) {
1680 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1681 p == td->td_proc || p->p_state == PRS_NEW) {
1685 if (p_cansignal(td, p, sig) == 0) {
1692 sx_sunlock(&allproc_lock);
1694 sx_slock(&proctree_lock);
1697 * zero pgid means send to my process group.
1699 pgrp = td->td_proc->p_pgrp;
1702 pgrp = pgfind(pgid);
1704 sx_sunlock(&proctree_lock);
1708 sx_sunlock(&proctree_lock);
1709 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1711 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1712 p->p_state == PRS_NEW ) {
1716 if (p_cansignal(td, p, sig) == 0) {
1725 return (nfound ? 0 : ESRCH);
1728 #ifndef _SYS_SYSPROTO_H_
1740 register struct thread *td;
1741 register struct kill_args *uap;
1743 register struct proc *p;
1746 AUDIT_ARG(signum, uap->signum);
1747 if ((u_int)uap->signum > _SIG_MAXSIG)
1751 /* kill single process */
1752 if ((p = pfind(uap->pid)) == NULL) {
1753 if ((p = zpfind(uap->pid)) == NULL)
1756 AUDIT_ARG(process, p);
1757 error = p_cansignal(td, p, uap->signum);
1758 if (error == 0 && uap->signum)
1759 psignal(p, uap->signum);
1763 AUDIT_ARG(pid, uap->pid);
1765 case -1: /* broadcast signal */
1766 return (killpg1(td, uap->signum, 0, 1));
1767 case 0: /* signal own process group */
1768 return (killpg1(td, uap->signum, 0, 0));
1769 default: /* negative explicit process group */
1770 return (killpg1(td, uap->signum, -uap->pid, 0));
1775 #if defined(COMPAT_43)
1776 #ifndef _SYS_SYSPROTO_H_
1777 struct okillpg_args {
1789 register struct okillpg_args *uap;
1792 AUDIT_ARG(signum, uap->signum);
1793 AUDIT_ARG(pid, uap->pgid);
1794 if ((u_int)uap->signum > _SIG_MAXSIG)
1797 return (killpg1(td, uap->signum, uap->pgid, 0));
1799 #endif /* COMPAT_43 */
1801 #ifndef _SYS_SYSPROTO_H_
1802 struct sigqueue_args {
1805 /* union sigval */ void *value;
1810 sigqueue(struct thread *td, struct sigqueue_args *uap)
1816 if ((u_int)uap->signum > _SIG_MAXSIG)
1820 * Specification says sigqueue can only send signal to
1826 if ((p = pfind(uap->pid)) == NULL) {
1827 if ((p = zpfind(uap->pid)) == NULL)
1830 error = p_cansignal(td, p, uap->signum);
1831 if (error == 0 && uap->signum != 0) {
1832 ksiginfo_init(&ksi);
1833 ksi.ksi_signo = uap->signum;
1834 ksi.ksi_code = SI_QUEUE;
1835 ksi.ksi_pid = td->td_proc->p_pid;
1836 ksi.ksi_uid = td->td_ucred->cr_ruid;
1837 ksi.ksi_value.sival_ptr = uap->value;
1838 error = tdsignal(p, NULL, ksi.ksi_signo, &ksi);
1845 * Send a signal to a process group.
1854 sx_slock(&proctree_lock);
1855 pgrp = pgfind(pgid);
1856 sx_sunlock(&proctree_lock);
1858 pgsignal(pgrp, sig, 0);
1865 * Send a signal to a process group. If checktty is 1,
1866 * limit to members which have a controlling terminal.
1869 pgsignal(pgrp, sig, checkctty)
1873 register struct proc *p;
1876 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1877 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1879 if (checkctty == 0 || p->p_flag & P_CONTROLT)
1887 * Send a signal caused by a trap to the current thread.
1888 * If it will be caught immediately, deliver it with correct code.
1889 * Otherwise, post it normally.
1894 trapsignal(struct thread *td, ksiginfo_t *ksi)
1905 sig = ksi->ksi_signo;
1906 code = ksi->ksi_code;
1907 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1910 if (td->td_pflags & TDP_SA) {
1911 if (td->td_mailbox == NULL)
1912 thread_user_enter(td);
1914 SIGDELSET(td->td_sigmask, sig);
1915 mtx_lock_spin(&sched_lock);
1917 * Force scheduling an upcall, so UTS has chance to
1918 * process the signal before thread runs again in
1922 td->td_upcall->ku_flags |= KUF_DOUPCALL;
1923 mtx_unlock_spin(&sched_lock);
1931 mtx_lock(&ps->ps_mtx);
1932 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1933 !SIGISMEMBER(td->td_sigmask, sig)) {
1934 p->p_stats->p_ru.ru_nsignals++;
1936 if (KTRPOINT(curthread, KTR_PSIG))
1937 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1938 &td->td_sigmask, code);
1941 if (!(td->td_pflags & TDP_SA))
1942 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1943 ksi, &td->td_sigmask);
1945 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1946 ksi, &td->td_sigmask);
1949 else if (td->td_mailbox == NULL) {
1950 mtx_unlock(&ps->ps_mtx);
1951 /* UTS caused a sync signal */
1952 p->p_code = code; /* XXX for core dump/debugger */
1953 p->p_sig = sig; /* XXX to verify code */
1956 mtx_unlock(&ps->ps_mtx);
1957 SIGADDSET(td->td_sigmask, sig);
1959 error = copyout(&ksi->ksi_info, &td->td_mailbox->tm_syncsig,
1962 /* UTS memory corrupted */
1964 sigexit(td, SIGSEGV);
1965 mtx_lock(&ps->ps_mtx);
1968 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
1969 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1970 SIGADDSET(td->td_sigmask, sig);
1971 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1973 * See kern_sigaction() for origin of this code.
1975 SIGDELSET(ps->ps_sigcatch, sig);
1976 if (sig != SIGCONT &&
1977 sigprop(sig) & SA_IGNORE)
1978 SIGADDSET(ps->ps_sigignore, sig);
1979 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1981 mtx_unlock(&ps->ps_mtx);
1984 * Avoid a possible infinite loop if the thread
1985 * masking the signal or process is ignoring the
1988 if (kern_forcesigexit &&
1989 (SIGISMEMBER(td->td_sigmask, sig) ||
1990 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1991 SIGDELSET(td->td_sigmask, sig);
1992 SIGDELSET(ps->ps_sigcatch, sig);
1993 SIGDELSET(ps->ps_sigignore, sig);
1994 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1996 mtx_unlock(&ps->ps_mtx);
1997 p->p_code = code; /* XXX for core dump/debugger */
1998 p->p_sig = sig; /* XXX to verify code */
1999 tdsignal(p, td, sig, ksi);
2004 static struct thread *
2005 sigtd(struct proc *p, int sig, int prop)
2007 struct thread *td, *signal_td;
2009 PROC_LOCK_ASSERT(p, MA_OWNED);
2012 * Check if current thread can handle the signal without
2013 * switching conetxt to another thread.
2015 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
2018 mtx_lock_spin(&sched_lock);
2019 FOREACH_THREAD_IN_PROC(p, td) {
2020 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2025 if (signal_td == NULL)
2026 signal_td = FIRST_THREAD_IN_PROC(p);
2027 mtx_unlock_spin(&sched_lock);
2032 * Send the signal to the process. If the signal has an action, the action
2033 * is usually performed by the target process rather than the caller; we add
2034 * the signal to the set of pending signals for the process.
2037 * o When a stop signal is sent to a sleeping process that takes the
2038 * default action, the process is stopped without awakening it.
2039 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2040 * regardless of the signal action (eg, blocked or ignored).
2042 * Other ignored signals are discarded immediately.
2047 psignal(struct proc *p, int sig)
2049 (void) tdsignal(p, NULL, sig, NULL);
2053 psignal_event(struct proc *p, struct sigevent *sigev, ksiginfo_t *ksi)
2055 struct thread *td = NULL;
2057 PROC_LOCK_ASSERT(p, MA_OWNED);
2059 KASSERT(!KSI_ONQ(ksi), ("psignal_event: ksi on queue"));
2062 * ksi_code and other fields should be set before
2063 * calling this function.
2065 ksi->ksi_signo = sigev->sigev_signo;
2066 ksi->ksi_value = sigev->sigev_value;
2067 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2068 td = thread_find(p, sigev->sigev_notify_thread_id);
2072 return (tdsignal(p, td, ksi->ksi_signo, ksi));
2079 tdsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2085 if (p->p_flag & P_SA)
2086 saved = p->p_sigqueue.sq_signals;
2087 ret = do_tdsignal(p, td, sig, ksi);
2088 if ((p->p_flag & P_SA) && !(p->p_flag & P_SIGEVENT)) {
2089 if (!SIGSETEQ(saved, p->p_sigqueue.sq_signals)) {
2090 /* pending set changed */
2091 p->p_flag |= P_SIGEVENT;
2092 wakeup(&p->p_siglist);
2099 do_tdsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2103 sigqueue_t *sigqueue;
2109 PROC_LOCK_ASSERT(p, MA_OWNED);
2111 if (!_SIG_VALID(sig))
2113 panic("do_tdsignal(): invalid signal");
2115 panic("tdsignal(): invalid signal");
2119 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("do_tdsignal: ksi on queue"));
2121 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("tdsignal: ksi on queue"));
2125 * IEEE Std 1003.1-2001: return success when killing a zombie.
2127 if (p->p_state == PRS_ZOMBIE) {
2128 if (ksi && (ksi->ksi_flags & KSI_INS))
2129 ksiginfo_tryfree(ksi);
2134 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2135 prop = sigprop(sig);
2138 * If the signal is blocked and not destined for this thread, then
2139 * assign it to the process so that we can find it later in the first
2140 * thread that unblocks it. Otherwise, assign it to this thread now.
2143 td = sigtd(p, sig, prop);
2144 if (SIGISMEMBER(td->td_sigmask, sig))
2145 sigqueue = &p->p_sigqueue;
2147 sigqueue = &td->td_sigqueue;
2149 KASSERT(td->td_proc == p, ("invalid thread"));
2150 sigqueue = &td->td_sigqueue;
2154 * If the signal is being ignored,
2155 * then we forget about it immediately.
2156 * (Note: we don't set SIGCONT in ps_sigignore,
2157 * and if it is set to SIG_IGN,
2158 * action will be SIG_DFL here.)
2160 mtx_lock(&ps->ps_mtx);
2161 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2162 mtx_unlock(&ps->ps_mtx);
2163 if (ksi && (ksi->ksi_flags & KSI_INS))
2164 ksiginfo_tryfree(ksi);
2167 if (SIGISMEMBER(td->td_sigmask, sig))
2169 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2173 if (SIGISMEMBER(ps->ps_sigintr, sig))
2177 mtx_unlock(&ps->ps_mtx);
2180 sigqueue_delete_stopmask_proc(p);
2181 else if (prop & SA_STOP) {
2183 * If sending a tty stop signal to a member of an orphaned
2184 * process group, discard the signal here if the action
2185 * is default; don't stop the process below if sleeping,
2186 * and don't clear any pending SIGCONT.
2188 if ((prop & SA_TTYSTOP) &&
2189 (p->p_pgrp->pg_jobc == 0) &&
2190 (action == SIG_DFL)) {
2191 if (ksi && (ksi->ksi_flags & KSI_INS))
2192 ksiginfo_tryfree(ksi);
2195 sigqueue_delete_proc(p, SIGCONT);
2196 if (p->p_flag & P_CONTINUED) {
2197 p->p_flag &= ~P_CONTINUED;
2198 PROC_LOCK(p->p_pptr);
2199 sigqueue_take(p->p_ksi);
2200 PROC_UNLOCK(p->p_pptr);
2204 ret = sigqueue_add(sigqueue, sig, ksi);
2209 * Defer further processing for signals which are held,
2210 * except that stopped processes must be continued by SIGCONT.
2212 if (action == SIG_HOLD &&
2213 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2216 * SIGKILL: Remove procfs STOPEVENTs.
2218 if (sig == SIGKILL) {
2219 /* from procfs_ioctl.c: PIOCBIC */
2221 /* from procfs_ioctl.c: PIOCCONT */
2226 * Some signals have a process-wide effect and a per-thread
2227 * component. Most processing occurs when the process next
2228 * tries to cross the user boundary, however there are some
2229 * times when processing needs to be done immediatly, such as
2230 * waking up threads so that they can cross the user boundary.
2231 * We try do the per-process part here.
2233 if (P_SHOULDSTOP(p)) {
2235 * The process is in stopped mode. All the threads should be
2236 * either winding down or already on the suspended queue.
2238 if (p->p_flag & P_TRACED) {
2240 * The traced process is already stopped,
2241 * so no further action is necessary.
2242 * No signal can restart us.
2247 if (sig == SIGKILL) {
2249 * SIGKILL sets process running.
2250 * It will die elsewhere.
2251 * All threads must be restarted.
2253 p->p_flag &= ~P_STOPPED_SIG;
2257 if (prop & SA_CONT) {
2259 * If SIGCONT is default (or ignored), we continue the
2260 * process but don't leave the signal in sigqueue as
2261 * it has no further action. If SIGCONT is held, we
2262 * continue the process and leave the signal in
2263 * sigqueue. If the process catches SIGCONT, let it
2264 * handle the signal itself. If it isn't waiting on
2265 * an event, it goes back to run state.
2266 * Otherwise, process goes back to sleep state.
2268 p->p_flag &= ~P_STOPPED_SIG;
2269 if (p->p_numthreads == p->p_suspcount) {
2270 p->p_flag |= P_CONTINUED;
2271 p->p_xstat = SIGCONT;
2272 PROC_LOCK(p->p_pptr);
2273 childproc_continued(p);
2274 PROC_UNLOCK(p->p_pptr);
2276 if (action == SIG_DFL) {
2277 sigqueue_delete(sigqueue, sig);
2278 } else if (action == SIG_CATCH) {
2281 * The process wants to catch it so it needs
2282 * to run at least one thread, but which one?
2283 * It would seem that the answer would be to
2284 * run an upcall in the next KSE to run, and
2285 * deliver the signal that way. In a NON KSE
2286 * process, we need to make sure that the
2287 * single thread is runnable asap.
2288 * XXXKSE for now however, make them all run.
2292 * The process wants to catch it so it needs
2293 * to run at least one thread, but which one?
2299 * The signal is not ignored or caught.
2301 mtx_lock_spin(&sched_lock);
2302 thread_unsuspend(p);
2303 mtx_unlock_spin(&sched_lock);
2307 if (prop & SA_STOP) {
2309 * Already stopped, don't need to stop again
2310 * (If we did the shell could get confused).
2311 * Just make sure the signal STOP bit set.
2313 p->p_flag |= P_STOPPED_SIG;
2314 sigqueue_delete(sigqueue, sig);
2319 * All other kinds of signals:
2320 * If a thread is sleeping interruptibly, simulate a
2321 * wakeup so that when it is continued it will be made
2322 * runnable and can look at the signal. However, don't make
2323 * the PROCESS runnable, leave it stopped.
2324 * It may run a bit until it hits a thread_suspend_check().
2326 mtx_lock_spin(&sched_lock);
2327 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2328 sleepq_abort(td, intrval);
2329 mtx_unlock_spin(&sched_lock);
2332 * Mutexes are short lived. Threads waiting on them will
2333 * hit thread_suspend_check() soon.
2335 } else if (p->p_state == PRS_NORMAL) {
2336 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2337 mtx_lock_spin(&sched_lock);
2338 tdsigwakeup(td, sig, action, intrval);
2339 mtx_unlock_spin(&sched_lock);
2343 MPASS(action == SIG_DFL);
2345 if (prop & SA_STOP) {
2346 if (p->p_flag & P_PPWAIT)
2348 p->p_flag |= P_STOPPED_SIG;
2350 mtx_lock_spin(&sched_lock);
2351 sig_suspend_threads(td, p, 1);
2352 if (p->p_numthreads == p->p_suspcount) {
2354 * only thread sending signal to another
2355 * process can reach here, if thread is sending
2356 * signal to its process, because thread does
2357 * not suspend itself here, p_numthreads
2358 * should never be equal to p_suspcount.
2361 mtx_unlock_spin(&sched_lock);
2362 sigqueue_delete_proc(p, p->p_xstat);
2364 mtx_unlock_spin(&sched_lock);
2371 /* Not in "NORMAL" state. discard the signal. */
2372 sigqueue_delete(sigqueue, sig);
2377 * The process is not stopped so we need to apply the signal to all the
2382 mtx_lock_spin(&sched_lock);
2383 tdsigwakeup(td, sig, action, intrval);
2384 thread_unsuspend(p);
2385 mtx_unlock_spin(&sched_lock);
2387 /* If we jump here, sched_lock should not be owned. */
2388 mtx_assert(&sched_lock, MA_NOTOWNED);
2393 * The force of a signal has been directed against a single
2394 * thread. We need to see what we can do about knocking it
2395 * out of any sleep it may be in etc.
2398 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2400 struct proc *p = td->td_proc;
2403 PROC_LOCK_ASSERT(p, MA_OWNED);
2404 mtx_assert(&sched_lock, MA_OWNED);
2405 prop = sigprop(sig);
2408 * Bring the priority of a thread up if we want it to get
2409 * killed in this lifetime.
2411 if (action == SIG_DFL && (prop & SA_KILL)) {
2413 sched_nice(td->td_proc, 0);
2414 if (td->td_priority > PUSER)
2415 sched_prio(td, PUSER);
2418 if (TD_ON_SLEEPQ(td)) {
2420 * If thread is sleeping uninterruptibly
2421 * we can't interrupt the sleep... the signal will
2422 * be noticed when the process returns through
2423 * trap() or syscall().
2425 if ((td->td_flags & TDF_SINTR) == 0)
2428 * If SIGCONT is default (or ignored) and process is
2429 * asleep, we are finished; the process should not
2432 if ((prop & SA_CONT) && action == SIG_DFL) {
2433 mtx_unlock_spin(&sched_lock);
2434 sigqueue_delete(&p->p_sigqueue, sig);
2436 * It may be on either list in this state.
2437 * Remove from both for now.
2439 sigqueue_delete(&td->td_sigqueue, sig);
2440 mtx_lock_spin(&sched_lock);
2445 * Give low priority threads a better chance to run.
2447 if (td->td_priority > PUSER)
2448 sched_prio(td, PUSER);
2450 sleepq_abort(td, intrval);
2453 * Other states do nothing with the signal immediately,
2454 * other than kicking ourselves if we are running.
2455 * It will either never be noticed, or noticed very soon.
2458 if (TD_IS_RUNNING(td) && td != curthread)
2465 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2469 PROC_LOCK_ASSERT(p, MA_OWNED);
2470 mtx_assert(&sched_lock, MA_OWNED);
2472 FOREACH_THREAD_IN_PROC(p, td2) {
2473 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2474 (td2->td_flags & TDF_SINTR) &&
2475 !TD_IS_SUSPENDED(td2)) {
2476 thread_suspend_one(td2);
2478 if (sending || td != td2)
2479 td2->td_flags |= TDF_ASTPENDING;
2481 if (TD_IS_RUNNING(td2) && td2 != td)
2482 forward_signal(td2);
2489 ptracestop(struct thread *td, int sig)
2491 struct proc *p = td->td_proc;
2493 PROC_LOCK_ASSERT(p, MA_OWNED);
2494 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2495 &p->p_mtx.mtx_object, "Stopping for traced signal");
2497 mtx_lock_spin(&sched_lock);
2498 td->td_flags |= TDF_XSIG;
2499 mtx_unlock_spin(&sched_lock);
2501 while ((p->p_flag & P_TRACED) && (td->td_flags & TDF_XSIG)) {
2502 if (p->p_flag & P_SINGLE_EXIT) {
2503 mtx_lock_spin(&sched_lock);
2504 td->td_flags &= ~TDF_XSIG;
2505 mtx_unlock_spin(&sched_lock);
2509 * Just make wait() to work, the last stopped thread
2514 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2515 mtx_lock_spin(&sched_lock);
2516 sig_suspend_threads(td, p, 0);
2519 thread_suspend_one(td);
2522 mi_switch(SW_VOL, NULL);
2523 mtx_unlock_spin(&sched_lock);
2526 if (!(p->p_flag & P_TRACED))
2528 if (td->td_flags & TDF_DBSUSPEND) {
2529 if (p->p_flag & P_SINGLE_EXIT)
2531 mtx_lock_spin(&sched_lock);
2535 return (td->td_xsig);
2539 * If the current process has received a signal (should be caught or cause
2540 * termination, should interrupt current syscall), return the signal number.
2541 * Stop signals with default action are processed immediately, then cleared;
2542 * they aren't returned. This is checked after each entry to the system for
2543 * a syscall or trap (though this can usually be done without calling issignal
2544 * by checking the pending signal masks in cursig.) The normal call
2547 * while (sig = cursig(curthread))
2556 sigset_t sigpending;
2557 int sig, prop, newsig;
2561 mtx_assert(&ps->ps_mtx, MA_OWNED);
2562 PROC_LOCK_ASSERT(p, MA_OWNED);
2564 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2566 sigpending = td->td_sigqueue.sq_signals;
2567 SIGSETNAND(sigpending, td->td_sigmask);
2569 if (p->p_flag & P_PPWAIT)
2570 SIG_STOPSIGMASK(sigpending);
2571 if (SIGISEMPTY(sigpending)) /* no signal to send */
2573 sig = sig_ffs(&sigpending);
2575 if (p->p_stops & S_SIG) {
2576 mtx_unlock(&ps->ps_mtx);
2577 stopevent(p, S_SIG, sig);
2578 mtx_lock(&ps->ps_mtx);
2582 * We should see pending but ignored signals
2583 * only if P_TRACED was on when they were posted.
2585 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2586 sigqueue_delete(&td->td_sigqueue, sig);
2588 if (td->td_pflags & TDP_SA)
2589 SIGADDSET(td->td_sigmask, sig);
2593 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
2595 * If traced, always stop.
2597 mtx_unlock(&ps->ps_mtx);
2598 newsig = ptracestop(td, sig);
2599 mtx_lock(&ps->ps_mtx);
2602 if (td->td_pflags & TDP_SA)
2603 SIGADDSET(td->td_sigmask, sig);
2606 if (sig != newsig) {
2610 * XXX shrug off debugger, it causes siginfo to
2613 sigqueue_get(&td->td_sigqueue, sig, &ksi);
2616 * If parent wants us to take the signal,
2617 * then it will leave it in p->p_xstat;
2618 * otherwise we just look for signals again.
2625 * Put the new signal into td_sigqueue. If the
2626 * signal is being masked, look for other signals.
2628 SIGADDSET(td->td_sigqueue.sq_signals, sig);
2630 if (td->td_pflags & TDP_SA)
2631 SIGDELSET(td->td_sigmask, sig);
2633 if (SIGISMEMBER(td->td_sigmask, sig))
2639 * If the traced bit got turned off, go back up
2640 * to the top to rescan signals. This ensures
2641 * that p_sig* and p_sigact are consistent.
2643 if ((p->p_flag & P_TRACED) == 0)
2647 prop = sigprop(sig);
2650 * Decide whether the signal should be returned.
2651 * Return the signal's number, or fall through
2652 * to clear it from the pending mask.
2654 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2656 case (intptr_t)SIG_DFL:
2658 * Don't take default actions on system processes.
2660 if (p->p_pid <= 1) {
2663 * Are you sure you want to ignore SIGSEGV
2666 printf("Process (pid %lu) got signal %d\n",
2667 (u_long)p->p_pid, sig);
2669 break; /* == ignore */
2672 * If there is a pending stop signal to process
2673 * with default action, stop here,
2674 * then clear the signal. However,
2675 * if process is member of an orphaned
2676 * process group, ignore tty stop signals.
2678 if (prop & SA_STOP) {
2679 if (p->p_flag & P_TRACED ||
2680 (p->p_pgrp->pg_jobc == 0 &&
2682 break; /* == ignore */
2683 mtx_unlock(&ps->ps_mtx);
2684 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2685 &p->p_mtx.mtx_object, "Catching SIGSTOP");
2686 p->p_flag |= P_STOPPED_SIG;
2688 mtx_lock_spin(&sched_lock);
2689 sig_suspend_threads(td, p, 0);
2691 thread_suspend_one(td);
2694 mi_switch(SW_INVOL, NULL);
2695 mtx_unlock_spin(&sched_lock);
2698 mtx_lock(&ps->ps_mtx);
2700 } else if (prop & SA_IGNORE) {
2702 * Except for SIGCONT, shouldn't get here.
2703 * Default action is to ignore; drop it.
2705 break; /* == ignore */
2710 case (intptr_t)SIG_IGN:
2712 * Masking above should prevent us ever trying
2713 * to take action on an ignored signal other
2714 * than SIGCONT, unless process is traced.
2716 if ((prop & SA_CONT) == 0 &&
2717 (p->p_flag & P_TRACED) == 0)
2718 printf("issignal\n");
2719 break; /* == ignore */
2723 * This signal has an action, let
2724 * postsig() process it.
2728 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2737 thread_stopped(struct proc *p)
2741 PROC_LOCK_ASSERT(p, MA_OWNED);
2742 mtx_assert(&sched_lock, MA_OWNED);
2746 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2747 mtx_unlock_spin(&sched_lock);
2748 p->p_flag &= ~P_WAITED;
2749 PROC_LOCK(p->p_pptr);
2750 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2751 CLD_TRAPPED : CLD_STOPPED);
2752 PROC_UNLOCK(p->p_pptr);
2753 mtx_lock_spin(&sched_lock);
2758 * Take the action for the specified signal
2759 * from the current set of pending signals.
2765 struct thread *td = curthread;
2766 register struct proc *p = td->td_proc;
2770 sigset_t returnmask;
2773 KASSERT(sig != 0, ("postsig"));
2775 PROC_LOCK_ASSERT(p, MA_OWNED);
2777 mtx_assert(&ps->ps_mtx, MA_OWNED);
2778 ksiginfo_init(&ksi);
2779 sigqueue_get(&td->td_sigqueue, sig, &ksi);
2780 ksi.ksi_signo = sig;
2781 if (ksi.ksi_code == SI_TIMER)
2782 itimer_accept(p, ksi.ksi_timerid, &ksi);
2783 action = ps->ps_sigact[_SIG_IDX(sig)];
2785 if (KTRPOINT(td, KTR_PSIG))
2786 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2787 &td->td_oldsigmask : &td->td_sigmask, 0);
2789 if (p->p_stops & S_SIG) {
2790 mtx_unlock(&ps->ps_mtx);
2791 stopevent(p, S_SIG, sig);
2792 mtx_lock(&ps->ps_mtx);
2796 if (!(td->td_pflags & TDP_SA) && action == SIG_DFL) {
2798 if (action == SIG_DFL) {
2801 * Default action, where the default is to kill
2802 * the process. (Other cases were ignored above.)
2804 mtx_unlock(&ps->ps_mtx);
2809 if (td->td_pflags & TDP_SA) {
2810 if (sig == SIGKILL) {
2811 mtx_unlock(&ps->ps_mtx);
2818 * If we get here, the signal must be caught.
2820 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2821 ("postsig action"));
2823 * Set the new mask value and also defer further
2824 * occurrences of this signal.
2826 * Special case: user has done a sigsuspend. Here the
2827 * current mask is not of interest, but rather the
2828 * mask from before the sigsuspend is what we want
2829 * restored after the signal processing is completed.
2831 if (td->td_pflags & TDP_OLDMASK) {
2832 returnmask = td->td_oldsigmask;
2833 td->td_pflags &= ~TDP_OLDMASK;
2835 returnmask = td->td_sigmask;
2837 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
2838 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2839 SIGADDSET(td->td_sigmask, sig);
2841 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2843 * See kern_sigaction() for origin of this code.
2845 SIGDELSET(ps->ps_sigcatch, sig);
2846 if (sig != SIGCONT &&
2847 sigprop(sig) & SA_IGNORE)
2848 SIGADDSET(ps->ps_sigignore, sig);
2849 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2851 p->p_stats->p_ru.ru_nsignals++;
2852 if (p->p_sig != sig) {
2860 if (td->td_pflags & TDP_SA)
2861 thread_signal_add(curthread, &ksi);
2863 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2865 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2871 * Kill the current process for stated reason.
2879 PROC_LOCK_ASSERT(p, MA_OWNED);
2880 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)",
2881 p, p->p_pid, p->p_comm);
2882 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
2883 p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2884 psignal(p, SIGKILL);
2888 * Force the current process to exit with the specified signal, dumping core
2889 * if appropriate. We bypass the normal tests for masked and caught signals,
2890 * allowing unrecoverable failures to terminate the process without changing
2891 * signal state. Mark the accounting record with the signal termination.
2892 * If dumping core, save the signal number for the debugger. Calls exit and
2902 struct proc *p = td->td_proc;
2904 PROC_LOCK_ASSERT(p, MA_OWNED);
2905 p->p_acflag |= AXSIG;
2907 * We must be single-threading to generate a core dump. This
2908 * ensures that the registers in the core file are up-to-date.
2909 * Also, the ELF dump handler assumes that the thread list doesn't
2910 * change out from under it.
2912 * XXX If another thread attempts to single-thread before us
2913 * (e.g. via fork()), we won't get a dump at all.
2915 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2918 * Log signals which would cause core dumps
2919 * (Log as LOG_INFO to appease those who don't want
2921 * XXX : Todo, as well as euid, write out ruid too
2922 * Note that coredump() drops proc lock.
2924 if (coredump(td) == 0)
2926 if (kern_logsigexit)
2928 "pid %d (%s), uid %d: exited on signal %d%s\n",
2929 p->p_pid, p->p_comm,
2930 td->td_ucred ? td->td_ucred->cr_uid : -1,
2932 sig & WCOREFLAG ? " (core dumped)" : "");
2935 exit1(td, W_EXITCODE(0, sig));
2940 * Send queued SIGCHLD to parent when child process's state
2944 sigparent(struct proc *p, int reason, int status)
2946 PROC_LOCK_ASSERT(p, MA_OWNED);
2947 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2949 if (p->p_ksi != NULL) {
2950 p->p_ksi->ksi_signo = SIGCHLD;
2951 p->p_ksi->ksi_code = reason;
2952 p->p_ksi->ksi_status = status;
2953 p->p_ksi->ksi_pid = p->p_pid;
2954 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2955 if (KSI_ONQ(p->p_ksi))
2958 tdsignal(p->p_pptr, NULL, SIGCHLD, p->p_ksi);
2962 childproc_jobstate(struct proc *p, int reason, int status)
2966 PROC_LOCK_ASSERT(p, MA_OWNED);
2967 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2970 * Wake up parent sleeping in kern_wait(), also send
2971 * SIGCHLD to parent, but SIGCHLD does not guarantee
2972 * that parent will awake, because parent may masked
2975 p->p_pptr->p_flag |= P_STATCHILD;
2978 ps = p->p_pptr->p_sigacts;
2979 mtx_lock(&ps->ps_mtx);
2980 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2981 mtx_unlock(&ps->ps_mtx);
2982 sigparent(p, reason, status);
2984 mtx_unlock(&ps->ps_mtx);
2988 childproc_stopped(struct proc *p, int reason)
2990 childproc_jobstate(p, reason, p->p_xstat);
2994 childproc_continued(struct proc *p)
2996 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3000 childproc_exited(struct proc *p)
3003 int status = p->p_xstat; /* convert to int */
3005 reason = CLD_EXITED;
3006 if (WCOREDUMP(status))
3007 reason = CLD_DUMPED;
3008 else if (WIFSIGNALED(status))
3009 reason = CLD_KILLED;
3011 * XXX avoid calling wakeup(p->p_pptr), the work is
3014 sigparent(p, reason, status);
3017 static char corefilename[MAXPATHLEN] = {"%N.core"};
3018 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3019 sizeof(corefilename), "process corefile name format string");
3022 * expand_name(name, uid, pid)
3023 * Expand the name described in corefilename, using name, uid, and pid.
3024 * corefilename is a printf-like string, with three format specifiers:
3025 * %N name of process ("name")
3026 * %P process id (pid)
3028 * For example, "%N.core" is the default; they can be disabled completely
3029 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3030 * This is controlled by the sysctl variable kern.corefile (see above).
3034 expand_name(name, uid, pid)
3039 const char *format, *appendstr;
3041 char buf[11]; /* Buffer for pid/uid -- max 4B */
3044 format = corefilename;
3045 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
3048 for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) {
3049 switch (format[i]) {
3050 case '%': /* Format character */
3052 switch (format[i]) {
3056 case 'N': /* process name */
3059 case 'P': /* process id */
3060 sprintf(buf, "%u", pid);
3063 case 'U': /* user id */
3064 sprintf(buf, "%u", uid);
3070 "Unknown format character %c in `%s'\n",
3073 l = strlen(appendstr);
3074 if ((n + l) >= MAXPATHLEN)
3076 memcpy(temp + n, appendstr, l);
3080 temp[n++] = format[i];
3083 if (format[i] != '\0')
3087 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too long\n",
3088 (long)pid, name, (u_long)uid);
3094 * Dump a process' core. The main routine does some
3095 * policy checking, and creates the name of the coredump;
3096 * then it passes on a vnode and a size limit to the process-specific
3097 * coredump routine if there is one; if there _is not_ one, it returns
3098 * ENOSYS; otherwise it returns the error from the process-specific routine.
3102 coredump(struct thread *td)
3104 struct proc *p = td->td_proc;
3105 register struct vnode *vp;
3106 register struct ucred *cred = td->td_ucred;
3108 struct nameidata nd;
3110 int error, error1, flags, locked;
3112 char *name; /* name of corefile */
3116 PROC_LOCK_ASSERT(p, MA_OWNED);
3117 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3118 _STOPEVENT(p, S_CORE, 0);
3120 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) {
3126 * Note that the bulk of limit checking is done after
3127 * the corefile is created. The exception is if the limit
3128 * for corefiles is 0, in which case we don't bother
3129 * creating the corefile at all. This layout means that
3130 * a corefile is truncated instead of not being created,
3131 * if it is larger than the limit.
3133 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3139 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid);
3142 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, name, td);
3143 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3144 error = vn_open(&nd, &flags, S_IRUSR | S_IWUSR, -1);
3148 vfslocked = NDHASGIANT(&nd);
3149 NDFREE(&nd, NDF_ONLY_PNBUF);
3152 /* Don't dump to non-regular files or files with links. */
3153 if (vp->v_type != VREG ||
3154 VOP_GETATTR(vp, &vattr, cred, td) || vattr.va_nlink != 1) {
3155 VOP_UNLOCK(vp, 0, td);
3160 VOP_UNLOCK(vp, 0, td);
3161 lf.l_whence = SEEK_SET;
3164 lf.l_type = F_WRLCK;
3165 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3167 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3168 lf.l_type = F_UNLCK;
3170 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3171 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3173 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3175 VFS_UNLOCK_GIANT(vfslocked);
3181 if (set_core_nodump_flag)
3182 vattr.va_flags = UF_NODUMP;
3183 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
3184 VOP_LEASE(vp, td, cred, LEASE_WRITE);
3185 VOP_SETATTR(vp, &vattr, cred, td);
3186 VOP_UNLOCK(vp, 0, td);
3187 vn_finished_write(mp);
3189 p->p_acflag |= ACORE;
3192 error = p->p_sysent->sv_coredump ?
3193 p->p_sysent->sv_coredump(td, vp, limit) :
3197 lf.l_type = F_UNLCK;
3198 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3201 error1 = vn_close(vp, FWRITE, cred, td);
3205 VFS_UNLOCK_GIANT(vfslocked);
3210 * Nonexistent system call-- signal process (may want to handle it).
3211 * Flag error in case process won't see signal immediately (blocked or ignored).
3213 #ifndef _SYS_SYSPROTO_H_
3225 struct nosys_args *args;
3227 struct proc *p = td->td_proc;
3236 * Send a SIGIO or SIGURG signal to a process or process group using
3237 * stored credentials rather than those of the current process.
3240 pgsigio(sigiop, sig, checkctty)
3241 struct sigio **sigiop;
3244 struct sigio *sigio;
3248 if (sigio == NULL) {
3252 if (sigio->sio_pgid > 0) {
3253 PROC_LOCK(sigio->sio_proc);
3254 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3255 psignal(sigio->sio_proc, sig);
3256 PROC_UNLOCK(sigio->sio_proc);
3257 } else if (sigio->sio_pgid < 0) {
3260 PGRP_LOCK(sigio->sio_pgrp);
3261 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3263 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3264 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3268 PGRP_UNLOCK(sigio->sio_pgrp);
3274 filt_sigattach(struct knote *kn)
3276 struct proc *p = curproc;
3278 kn->kn_ptr.p_proc = p;
3279 kn->kn_flags |= EV_CLEAR; /* automatically set */
3281 knlist_add(&p->p_klist, kn, 0);
3287 filt_sigdetach(struct knote *kn)
3289 struct proc *p = kn->kn_ptr.p_proc;
3291 knlist_remove(&p->p_klist, kn, 0);
3295 * signal knotes are shared with proc knotes, so we apply a mask to
3296 * the hint in order to differentiate them from process hints. This
3297 * could be avoided by using a signal-specific knote list, but probably
3298 * isn't worth the trouble.
3301 filt_signal(struct knote *kn, long hint)
3304 if (hint & NOTE_SIGNAL) {
3305 hint &= ~NOTE_SIGNAL;
3307 if (kn->kn_id == hint)
3310 return (kn->kn_data != 0);
3318 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3320 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3325 sigacts_free(struct sigacts *ps)
3328 mtx_lock(&ps->ps_mtx);
3330 if (ps->ps_refcnt == 0) {
3331 mtx_destroy(&ps->ps_mtx);
3332 free(ps, M_SUBPROC);
3334 mtx_unlock(&ps->ps_mtx);
3338 sigacts_hold(struct sigacts *ps)
3340 mtx_lock(&ps->ps_mtx);
3342 mtx_unlock(&ps->ps_mtx);
3347 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3350 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3351 mtx_lock(&src->ps_mtx);
3352 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3353 mtx_unlock(&src->ps_mtx);
3357 sigacts_shared(struct sigacts *ps)
3361 mtx_lock(&ps->ps_mtx);
3362 shared = ps->ps_refcnt > 1;
3363 mtx_unlock(&ps->ps_mtx);