2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
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11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
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19 * may be used to endorse or promote products derived from this software
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34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
41 #include "opt_kdtrace.h"
42 #include "opt_ktrace.h"
44 #include "opt_procdesc.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/signalvar.h>
49 #include <sys/vnode.h>
51 #include <sys/capability.h>
52 #include <sys/condvar.h>
53 #include <sys/event.h>
54 #include <sys/fcntl.h>
55 #include <sys/imgact.h>
56 #include <sys/kernel.h>
58 #include <sys/ktrace.h>
60 #include <sys/malloc.h>
61 #include <sys/mutex.h>
62 #include <sys/refcount.h>
63 #include <sys/namei.h>
65 #include <sys/procdesc.h>
66 #include <sys/posix4.h>
67 #include <sys/pioctl.h>
68 #include <sys/racct.h>
69 #include <sys/resourcevar.h>
72 #include <sys/sleepqueue.h>
76 #include <sys/syscallsubr.h>
77 #include <sys/sysctl.h>
78 #include <sys/sysent.h>
79 #include <sys/syslog.h>
80 #include <sys/sysproto.h>
81 #include <sys/timers.h>
82 #include <sys/unistd.h>
85 #include <vm/vm_extern.h>
90 #include <machine/cpu.h>
92 #include <security/audit/audit.h>
94 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE3(proc, kernel, , signal__send, "struct thread *",
98 "struct proc *", "int");
99 SDT_PROBE_DEFINE2(proc, kernel, , signal__clear, "int",
101 SDT_PROBE_DEFINE3(proc, kernel, , signal__discard,
102 "struct thread *", "struct proc *", "int");
104 static int coredump(struct thread *);
105 static int killpg1(struct thread *td, int sig, int pgid, int all,
107 static int issignal(struct thread *td);
108 static int sigprop(int sig);
109 static void tdsigwakeup(struct thread *, int, sig_t, int);
110 static void sig_suspend_threads(struct thread *, struct proc *, int);
111 static int filt_sigattach(struct knote *kn);
112 static void filt_sigdetach(struct knote *kn);
113 static int filt_signal(struct knote *kn, long hint);
114 static struct thread *sigtd(struct proc *p, int sig, int prop);
115 static void sigqueue_start(void);
117 static uma_zone_t ksiginfo_zone = NULL;
118 struct filterops sig_filtops = {
120 .f_attach = filt_sigattach,
121 .f_detach = filt_sigdetach,
122 .f_event = filt_signal,
125 static int kern_logsigexit = 1;
126 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
128 "Log processes quitting on abnormal signals to syslog(3)");
130 static int kern_forcesigexit = 1;
131 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
132 &kern_forcesigexit, 0, "Force trap signal to be handled");
134 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
135 "POSIX real time signal");
137 static int max_pending_per_proc = 128;
138 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
139 &max_pending_per_proc, 0, "Max pending signals per proc");
141 static int preallocate_siginfo = 1024;
142 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
143 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
144 &preallocate_siginfo, 0, "Preallocated signal memory size");
146 static int signal_overflow = 0;
147 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
148 &signal_overflow, 0, "Number of signals overflew");
150 static int signal_alloc_fail = 0;
151 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
152 &signal_alloc_fail, 0, "signals failed to be allocated");
154 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
157 * Policy -- Can ucred cr1 send SIGIO to process cr2?
158 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
159 * in the right situations.
161 #define CANSIGIO(cr1, cr2) \
162 ((cr1)->cr_uid == 0 || \
163 (cr1)->cr_ruid == (cr2)->cr_ruid || \
164 (cr1)->cr_uid == (cr2)->cr_ruid || \
165 (cr1)->cr_ruid == (cr2)->cr_uid || \
166 (cr1)->cr_uid == (cr2)->cr_uid)
168 static int sugid_coredump;
169 TUNABLE_INT("kern.sugid_coredump", &sugid_coredump);
170 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
171 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
173 static int capmode_coredump;
174 TUNABLE_INT("kern.capmode_coredump", &capmode_coredump);
175 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RW,
176 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
178 static int do_coredump = 1;
179 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
180 &do_coredump, 0, "Enable/Disable coredumps");
182 static int set_core_nodump_flag = 0;
183 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
184 0, "Enable setting the NODUMP flag on coredump files");
187 * Signal properties and actions.
188 * The array below categorizes the signals and their default actions
189 * according to the following properties:
191 #define SA_KILL 0x01 /* terminates process by default */
192 #define SA_CORE 0x02 /* ditto and coredumps */
193 #define SA_STOP 0x04 /* suspend process */
194 #define SA_TTYSTOP 0x08 /* ditto, from tty */
195 #define SA_IGNORE 0x10 /* ignore by default */
196 #define SA_CONT 0x20 /* continue if suspended */
197 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
199 static int sigproptbl[NSIG] = {
200 SA_KILL, /* SIGHUP */
201 SA_KILL, /* SIGINT */
202 SA_KILL|SA_CORE, /* SIGQUIT */
203 SA_KILL|SA_CORE, /* SIGILL */
204 SA_KILL|SA_CORE, /* SIGTRAP */
205 SA_KILL|SA_CORE, /* SIGABRT */
206 SA_KILL|SA_CORE, /* SIGEMT */
207 SA_KILL|SA_CORE, /* SIGFPE */
208 SA_KILL, /* SIGKILL */
209 SA_KILL|SA_CORE, /* SIGBUS */
210 SA_KILL|SA_CORE, /* SIGSEGV */
211 SA_KILL|SA_CORE, /* SIGSYS */
212 SA_KILL, /* SIGPIPE */
213 SA_KILL, /* SIGALRM */
214 SA_KILL, /* SIGTERM */
215 SA_IGNORE, /* SIGURG */
216 SA_STOP, /* SIGSTOP */
217 SA_STOP|SA_TTYSTOP, /* SIGTSTP */
218 SA_IGNORE|SA_CONT, /* SIGCONT */
219 SA_IGNORE, /* SIGCHLD */
220 SA_STOP|SA_TTYSTOP, /* SIGTTIN */
221 SA_STOP|SA_TTYSTOP, /* SIGTTOU */
222 SA_IGNORE, /* SIGIO */
223 SA_KILL, /* SIGXCPU */
224 SA_KILL, /* SIGXFSZ */
225 SA_KILL, /* SIGVTALRM */
226 SA_KILL, /* SIGPROF */
227 SA_IGNORE, /* SIGWINCH */
228 SA_IGNORE, /* SIGINFO */
229 SA_KILL, /* SIGUSR1 */
230 SA_KILL, /* SIGUSR2 */
233 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
238 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
239 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
240 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
241 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
242 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
243 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
247 ksiginfo_alloc(int wait)
254 if (ksiginfo_zone != NULL)
255 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
260 ksiginfo_free(ksiginfo_t *ksi)
262 uma_zfree(ksiginfo_zone, ksi);
266 ksiginfo_tryfree(ksiginfo_t *ksi)
268 if (!(ksi->ksi_flags & KSI_EXT)) {
269 uma_zfree(ksiginfo_zone, ksi);
276 sigqueue_init(sigqueue_t *list, struct proc *p)
278 SIGEMPTYSET(list->sq_signals);
279 SIGEMPTYSET(list->sq_kill);
280 TAILQ_INIT(&list->sq_list);
282 list->sq_flags = SQ_INIT;
286 * Get a signal's ksiginfo.
288 * 0 - signal not found
289 * others - signal number
292 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
294 struct proc *p = sq->sq_proc;
295 struct ksiginfo *ksi, *next;
298 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
300 if (!SIGISMEMBER(sq->sq_signals, signo))
303 if (SIGISMEMBER(sq->sq_kill, signo)) {
305 SIGDELSET(sq->sq_kill, signo);
308 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
309 if (ksi->ksi_signo == signo) {
311 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
312 ksi->ksi_sigq = NULL;
313 ksiginfo_copy(ksi, si);
314 if (ksiginfo_tryfree(ksi) && p != NULL)
323 SIGDELSET(sq->sq_signals, signo);
324 si->ksi_signo = signo;
329 sigqueue_take(ksiginfo_t *ksi)
335 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
339 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
340 ksi->ksi_sigq = NULL;
341 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
344 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
345 kp = TAILQ_NEXT(kp, ksi_link)) {
346 if (kp->ksi_signo == ksi->ksi_signo)
349 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
350 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
354 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
356 struct proc *p = sq->sq_proc;
357 struct ksiginfo *ksi;
360 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
362 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
363 SIGADDSET(sq->sq_kill, signo);
367 /* directly insert the ksi, don't copy it */
368 if (si->ksi_flags & KSI_INS) {
369 if (si->ksi_flags & KSI_HEAD)
370 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
372 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
377 if (__predict_false(ksiginfo_zone == NULL)) {
378 SIGADDSET(sq->sq_kill, signo);
382 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
385 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
391 ksiginfo_copy(si, ksi);
392 ksi->ksi_signo = signo;
393 if (si->ksi_flags & KSI_HEAD)
394 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
396 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
400 if ((si->ksi_flags & KSI_TRAP) != 0 ||
401 (si->ksi_flags & KSI_SIGQ) == 0) {
403 SIGADDSET(sq->sq_kill, signo);
412 SIGADDSET(sq->sq_signals, signo);
417 sigqueue_flush(sigqueue_t *sq)
419 struct proc *p = sq->sq_proc;
422 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
425 PROC_LOCK_ASSERT(p, MA_OWNED);
427 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
428 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
429 ksi->ksi_sigq = NULL;
430 if (ksiginfo_tryfree(ksi) && p != NULL)
434 SIGEMPTYSET(sq->sq_signals);
435 SIGEMPTYSET(sq->sq_kill);
439 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
442 struct proc *p1, *p2;
443 ksiginfo_t *ksi, *next;
445 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
446 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
449 /* Move siginfo to target list */
450 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
451 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
452 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
455 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
462 /* Move pending bits to target list */
464 SIGSETAND(tmp, *set);
465 SIGSETOR(dst->sq_kill, tmp);
466 SIGSETNAND(src->sq_kill, tmp);
468 tmp = src->sq_signals;
469 SIGSETAND(tmp, *set);
470 SIGSETOR(dst->sq_signals, tmp);
471 SIGSETNAND(src->sq_signals, tmp);
476 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
481 SIGADDSET(set, signo);
482 sigqueue_move_set(src, dst, &set);
487 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
489 struct proc *p = sq->sq_proc;
490 ksiginfo_t *ksi, *next;
492 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
494 /* Remove siginfo queue */
495 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
496 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
497 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
498 ksi->ksi_sigq = NULL;
499 if (ksiginfo_tryfree(ksi) && p != NULL)
503 SIGSETNAND(sq->sq_kill, *set);
504 SIGSETNAND(sq->sq_signals, *set);
508 sigqueue_delete(sigqueue_t *sq, int signo)
513 SIGADDSET(set, signo);
514 sigqueue_delete_set(sq, &set);
517 /* Remove a set of signals for a process */
519 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
524 PROC_LOCK_ASSERT(p, MA_OWNED);
526 sigqueue_init(&worklist, NULL);
527 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
529 FOREACH_THREAD_IN_PROC(p, td0)
530 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
532 sigqueue_flush(&worklist);
536 sigqueue_delete_proc(struct proc *p, int signo)
541 SIGADDSET(set, signo);
542 sigqueue_delete_set_proc(p, &set);
546 sigqueue_delete_stopmask_proc(struct proc *p)
551 SIGADDSET(set, SIGSTOP);
552 SIGADDSET(set, SIGTSTP);
553 SIGADDSET(set, SIGTTIN);
554 SIGADDSET(set, SIGTTOU);
555 sigqueue_delete_set_proc(p, &set);
559 * Determine signal that should be delivered to thread td, the current
560 * thread, 0 if none. If there is a pending stop signal with default
561 * action, the process stops in issignal().
564 cursig(struct thread *td)
566 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
567 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
568 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
569 return (SIGPENDING(td) ? issignal(td) : 0);
573 * Arrange for ast() to handle unmasked pending signals on return to user
574 * mode. This must be called whenever a signal is added to td_sigqueue or
575 * unmasked in td_sigmask.
578 signotify(struct thread *td)
584 PROC_LOCK_ASSERT(p, MA_OWNED);
586 if (SIGPENDING(td)) {
588 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
594 sigonstack(size_t sp)
596 struct thread *td = curthread;
598 return ((td->td_pflags & TDP_ALTSTACK) ?
599 #if defined(COMPAT_43)
600 ((td->td_sigstk.ss_size == 0) ?
601 (td->td_sigstk.ss_flags & SS_ONSTACK) :
602 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
604 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
613 if (sig > 0 && sig < NSIG)
614 return (sigproptbl[_SIG_IDX(sig)]);
619 sig_ffs(sigset_t *set)
623 for (i = 0; i < _SIG_WORDS; i++)
625 return (ffs(set->__bits[i]) + (i * 32));
630 sigact_flag_test(struct sigaction *act, int flag)
634 * SA_SIGINFO is reset when signal disposition is set to
635 * ignore or default. Other flags are kept according to user
638 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
639 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
640 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
650 kern_sigaction(td, sig, act, oact, flags)
653 struct sigaction *act, *oact;
657 struct proc *p = td->td_proc;
659 if (!_SIG_VALID(sig))
661 if (act != NULL && (act->sa_flags & ~(SA_ONSTACK | SA_RESTART |
662 SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER | SA_NOCLDWAIT |
668 mtx_lock(&ps->ps_mtx);
670 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
672 if (SIGISMEMBER(ps->ps_sigonstack, sig))
673 oact->sa_flags |= SA_ONSTACK;
674 if (!SIGISMEMBER(ps->ps_sigintr, sig))
675 oact->sa_flags |= SA_RESTART;
676 if (SIGISMEMBER(ps->ps_sigreset, sig))
677 oact->sa_flags |= SA_RESETHAND;
678 if (SIGISMEMBER(ps->ps_signodefer, sig))
679 oact->sa_flags |= SA_NODEFER;
680 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
681 oact->sa_flags |= SA_SIGINFO;
683 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
685 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
686 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
687 oact->sa_flags |= SA_NOCLDSTOP;
688 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
689 oact->sa_flags |= SA_NOCLDWAIT;
692 if ((sig == SIGKILL || sig == SIGSTOP) &&
693 act->sa_handler != SIG_DFL) {
694 mtx_unlock(&ps->ps_mtx);
700 * Change setting atomically.
703 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
704 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
705 if (sigact_flag_test(act, SA_SIGINFO)) {
706 ps->ps_sigact[_SIG_IDX(sig)] =
707 (__sighandler_t *)act->sa_sigaction;
708 SIGADDSET(ps->ps_siginfo, sig);
710 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
711 SIGDELSET(ps->ps_siginfo, sig);
713 if (!sigact_flag_test(act, SA_RESTART))
714 SIGADDSET(ps->ps_sigintr, sig);
716 SIGDELSET(ps->ps_sigintr, sig);
717 if (sigact_flag_test(act, SA_ONSTACK))
718 SIGADDSET(ps->ps_sigonstack, sig);
720 SIGDELSET(ps->ps_sigonstack, sig);
721 if (sigact_flag_test(act, SA_RESETHAND))
722 SIGADDSET(ps->ps_sigreset, sig);
724 SIGDELSET(ps->ps_sigreset, sig);
725 if (sigact_flag_test(act, SA_NODEFER))
726 SIGADDSET(ps->ps_signodefer, sig);
728 SIGDELSET(ps->ps_signodefer, sig);
729 if (sig == SIGCHLD) {
730 if (act->sa_flags & SA_NOCLDSTOP)
731 ps->ps_flag |= PS_NOCLDSTOP;
733 ps->ps_flag &= ~PS_NOCLDSTOP;
734 if (act->sa_flags & SA_NOCLDWAIT) {
736 * Paranoia: since SA_NOCLDWAIT is implemented
737 * by reparenting the dying child to PID 1 (and
738 * trust it to reap the zombie), PID 1 itself
739 * is forbidden to set SA_NOCLDWAIT.
742 ps->ps_flag &= ~PS_NOCLDWAIT;
744 ps->ps_flag |= PS_NOCLDWAIT;
746 ps->ps_flag &= ~PS_NOCLDWAIT;
747 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
748 ps->ps_flag |= PS_CLDSIGIGN;
750 ps->ps_flag &= ~PS_CLDSIGIGN;
753 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
754 * and for signals set to SIG_DFL where the default is to
755 * ignore. However, don't put SIGCONT in ps_sigignore, as we
756 * have to restart the process.
758 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
759 (sigprop(sig) & SA_IGNORE &&
760 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
761 /* never to be seen again */
762 sigqueue_delete_proc(p, sig);
764 /* easier in psignal */
765 SIGADDSET(ps->ps_sigignore, sig);
766 SIGDELSET(ps->ps_sigcatch, sig);
768 SIGDELSET(ps->ps_sigignore, sig);
769 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
770 SIGDELSET(ps->ps_sigcatch, sig);
772 SIGADDSET(ps->ps_sigcatch, sig);
774 #ifdef COMPAT_FREEBSD4
775 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
776 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
777 (flags & KSA_FREEBSD4) == 0)
778 SIGDELSET(ps->ps_freebsd4, sig);
780 SIGADDSET(ps->ps_freebsd4, sig);
783 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
784 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
785 (flags & KSA_OSIGSET) == 0)
786 SIGDELSET(ps->ps_osigset, sig);
788 SIGADDSET(ps->ps_osigset, sig);
791 mtx_unlock(&ps->ps_mtx);
796 #ifndef _SYS_SYSPROTO_H_
797 struct sigaction_args {
799 struct sigaction *act;
800 struct sigaction *oact;
804 sys_sigaction(td, uap)
806 register struct sigaction_args *uap;
808 struct sigaction act, oact;
809 register struct sigaction *actp, *oactp;
812 actp = (uap->act != NULL) ? &act : NULL;
813 oactp = (uap->oact != NULL) ? &oact : NULL;
815 error = copyin(uap->act, actp, sizeof(act));
819 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
821 error = copyout(oactp, uap->oact, sizeof(oact));
825 #ifdef COMPAT_FREEBSD4
826 #ifndef _SYS_SYSPROTO_H_
827 struct freebsd4_sigaction_args {
829 struct sigaction *act;
830 struct sigaction *oact;
834 freebsd4_sigaction(td, uap)
836 register struct freebsd4_sigaction_args *uap;
838 struct sigaction act, oact;
839 register struct sigaction *actp, *oactp;
843 actp = (uap->act != NULL) ? &act : NULL;
844 oactp = (uap->oact != NULL) ? &oact : NULL;
846 error = copyin(uap->act, actp, sizeof(act));
850 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
852 error = copyout(oactp, uap->oact, sizeof(oact));
855 #endif /* COMAPT_FREEBSD4 */
857 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
858 #ifndef _SYS_SYSPROTO_H_
859 struct osigaction_args {
861 struct osigaction *nsa;
862 struct osigaction *osa;
868 register struct osigaction_args *uap;
870 struct osigaction sa;
871 struct sigaction nsa, osa;
872 register struct sigaction *nsap, *osap;
875 if (uap->signum <= 0 || uap->signum >= ONSIG)
878 nsap = (uap->nsa != NULL) ? &nsa : NULL;
879 osap = (uap->osa != NULL) ? &osa : NULL;
882 error = copyin(uap->nsa, &sa, sizeof(sa));
885 nsap->sa_handler = sa.sa_handler;
886 nsap->sa_flags = sa.sa_flags;
887 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
889 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
890 if (osap && !error) {
891 sa.sa_handler = osap->sa_handler;
892 sa.sa_flags = osap->sa_flags;
893 SIG2OSIG(osap->sa_mask, sa.sa_mask);
894 error = copyout(&sa, uap->osa, sizeof(sa));
899 #if !defined(__i386__)
900 /* Avoid replicating the same stub everywhere */
904 struct osigreturn_args *uap;
907 return (nosys(td, (struct nosys_args *)uap));
910 #endif /* COMPAT_43 */
913 * Initialize signal state for process 0;
914 * set to ignore signals that are ignored by default.
925 mtx_lock(&ps->ps_mtx);
926 for (i = 1; i <= NSIG; i++) {
927 if (sigprop(i) & SA_IGNORE && i != SIGCONT) {
928 SIGADDSET(ps->ps_sigignore, i);
931 mtx_unlock(&ps->ps_mtx);
936 * Reset specified signal to the default disposition.
939 sigdflt(struct sigacts *ps, int sig)
942 mtx_assert(&ps->ps_mtx, MA_OWNED);
943 SIGDELSET(ps->ps_sigcatch, sig);
944 if ((sigprop(sig) & SA_IGNORE) != 0 && sig != SIGCONT)
945 SIGADDSET(ps->ps_sigignore, sig);
946 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
947 SIGDELSET(ps->ps_siginfo, sig);
951 * Reset signals for an exec of the specified process.
954 execsigs(struct proc *p)
961 * Reset caught signals. Held signals remain held
962 * through td_sigmask (unless they were caught,
963 * and are now ignored by default).
965 PROC_LOCK_ASSERT(p, MA_OWNED);
966 td = FIRST_THREAD_IN_PROC(p);
968 mtx_lock(&ps->ps_mtx);
969 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
970 sig = sig_ffs(&ps->ps_sigcatch);
972 if ((sigprop(sig) & SA_IGNORE) != 0)
973 sigqueue_delete_proc(p, sig);
976 * Reset stack state to the user stack.
977 * Clear set of signals caught on the signal stack.
979 td->td_sigstk.ss_flags = SS_DISABLE;
980 td->td_sigstk.ss_size = 0;
981 td->td_sigstk.ss_sp = 0;
982 td->td_pflags &= ~TDP_ALTSTACK;
984 * Reset no zombies if child dies flag as Solaris does.
986 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
987 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
988 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
989 mtx_unlock(&ps->ps_mtx);
995 * Manipulate signal mask.
998 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1001 sigset_t new_block, oset1;
1006 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1009 *oset = td->td_sigmask;
1016 oset1 = td->td_sigmask;
1017 SIGSETOR(td->td_sigmask, *set);
1018 new_block = td->td_sigmask;
1019 SIGSETNAND(new_block, oset1);
1022 SIGSETNAND(td->td_sigmask, *set);
1027 oset1 = td->td_sigmask;
1028 if (flags & SIGPROCMASK_OLD)
1029 SIGSETLO(td->td_sigmask, *set);
1031 td->td_sigmask = *set;
1032 new_block = td->td_sigmask;
1033 SIGSETNAND(new_block, oset1);
1042 * The new_block set contains signals that were not previously
1043 * blocked, but are blocked now.
1045 * In case we block any signal that was not previously blocked
1046 * for td, and process has the signal pending, try to schedule
1047 * signal delivery to some thread that does not block the
1048 * signal, possibly waking it up.
1050 if (p->p_numthreads != 1)
1051 reschedule_signals(p, new_block, flags);
1055 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1060 #ifndef _SYS_SYSPROTO_H_
1061 struct sigprocmask_args {
1063 const sigset_t *set;
1068 sys_sigprocmask(td, uap)
1069 register struct thread *td;
1070 struct sigprocmask_args *uap;
1073 sigset_t *setp, *osetp;
1076 setp = (uap->set != NULL) ? &set : NULL;
1077 osetp = (uap->oset != NULL) ? &oset : NULL;
1079 error = copyin(uap->set, setp, sizeof(set));
1083 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1084 if (osetp && !error) {
1085 error = copyout(osetp, uap->oset, sizeof(oset));
1090 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1091 #ifndef _SYS_SYSPROTO_H_
1092 struct osigprocmask_args {
1098 osigprocmask(td, uap)
1099 register struct thread *td;
1100 struct osigprocmask_args *uap;
1105 OSIG2SIG(uap->mask, set);
1106 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1107 SIG2OSIG(oset, td->td_retval[0]);
1110 #endif /* COMPAT_43 */
1113 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1119 error = copyin(uap->set, &set, sizeof(set));
1121 td->td_retval[0] = error;
1125 error = kern_sigtimedwait(td, set, &ksi, NULL);
1127 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1129 if (error == ERESTART)
1131 td->td_retval[0] = error;
1135 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1136 td->td_retval[0] = error;
1141 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1144 struct timespec *timeout;
1150 error = copyin(uap->timeout, &ts, sizeof(ts));
1158 error = copyin(uap->set, &set, sizeof(set));
1162 error = kern_sigtimedwait(td, set, &ksi, timeout);
1167 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1170 td->td_retval[0] = ksi.ksi_signo;
1175 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1181 error = copyin(uap->set, &set, sizeof(set));
1185 error = kern_sigtimedwait(td, set, &ksi, NULL);
1190 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1193 td->td_retval[0] = ksi.ksi_signo;
1198 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1199 struct timespec *timeout)
1202 sigset_t saved_mask, new_block;
1204 int error, sig, timo, timevalid = 0;
1205 struct timespec rts, ets, ts;
1213 if (timeout != NULL) {
1214 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1216 getnanouptime(&rts);
1218 timespecadd(&ets, timeout);
1222 /* Some signals can not be waited for. */
1223 SIG_CANTMASK(waitset);
1226 saved_mask = td->td_sigmask;
1227 SIGSETNAND(td->td_sigmask, waitset);
1229 mtx_lock(&ps->ps_mtx);
1231 mtx_unlock(&ps->ps_mtx);
1232 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1233 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1234 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1244 * POSIX says this must be checked after looking for pending
1247 if (timeout != NULL) {
1252 getnanouptime(&rts);
1253 if (timespeccmp(&rts, &ets, >=)) {
1258 timespecsub(&ts, &rts);
1259 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1265 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1267 if (timeout != NULL) {
1268 if (error == ERESTART) {
1269 /* Timeout can not be restarted. */
1271 } else if (error == EAGAIN) {
1272 /* We will calculate timeout by ourself. */
1278 new_block = saved_mask;
1279 SIGSETNAND(new_block, td->td_sigmask);
1280 td->td_sigmask = saved_mask;
1282 * Fewer signals can be delivered to us, reschedule signal
1285 if (p->p_numthreads != 1)
1286 reschedule_signals(p, new_block, 0);
1289 SDT_PROBE(proc, kernel, , signal__clear, sig, ksi, 0, 0, 0);
1291 if (ksi->ksi_code == SI_TIMER)
1292 itimer_accept(p, ksi->ksi_timerid, ksi);
1295 if (KTRPOINT(td, KTR_PSIG)) {
1298 mtx_lock(&ps->ps_mtx);
1299 action = ps->ps_sigact[_SIG_IDX(sig)];
1300 mtx_unlock(&ps->ps_mtx);
1301 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1311 #ifndef _SYS_SYSPROTO_H_
1312 struct sigpending_args {
1317 sys_sigpending(td, uap)
1319 struct sigpending_args *uap;
1321 struct proc *p = td->td_proc;
1325 pending = p->p_sigqueue.sq_signals;
1326 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1328 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1331 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1332 #ifndef _SYS_SYSPROTO_H_
1333 struct osigpending_args {
1338 osigpending(td, uap)
1340 struct osigpending_args *uap;
1342 struct proc *p = td->td_proc;
1346 pending = p->p_sigqueue.sq_signals;
1347 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1349 SIG2OSIG(pending, td->td_retval[0]);
1352 #endif /* COMPAT_43 */
1354 #if defined(COMPAT_43)
1356 * Generalized interface signal handler, 4.3-compatible.
1358 #ifndef _SYS_SYSPROTO_H_
1359 struct osigvec_args {
1369 register struct osigvec_args *uap;
1372 struct sigaction nsa, osa;
1373 register struct sigaction *nsap, *osap;
1376 if (uap->signum <= 0 || uap->signum >= ONSIG)
1378 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1379 osap = (uap->osv != NULL) ? &osa : NULL;
1381 error = copyin(uap->nsv, &vec, sizeof(vec));
1384 nsap->sa_handler = vec.sv_handler;
1385 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1386 nsap->sa_flags = vec.sv_flags;
1387 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1389 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1390 if (osap && !error) {
1391 vec.sv_handler = osap->sa_handler;
1392 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1393 vec.sv_flags = osap->sa_flags;
1394 vec.sv_flags &= ~SA_NOCLDWAIT;
1395 vec.sv_flags ^= SA_RESTART;
1396 error = copyout(&vec, uap->osv, sizeof(vec));
1401 #ifndef _SYS_SYSPROTO_H_
1402 struct osigblock_args {
1408 register struct thread *td;
1409 struct osigblock_args *uap;
1413 OSIG2SIG(uap->mask, set);
1414 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1415 SIG2OSIG(oset, td->td_retval[0]);
1419 #ifndef _SYS_SYSPROTO_H_
1420 struct osigsetmask_args {
1425 osigsetmask(td, uap)
1427 struct osigsetmask_args *uap;
1431 OSIG2SIG(uap->mask, set);
1432 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1433 SIG2OSIG(oset, td->td_retval[0]);
1436 #endif /* COMPAT_43 */
1439 * Suspend calling thread until signal, providing mask to be set in the
1442 #ifndef _SYS_SYSPROTO_H_
1443 struct sigsuspend_args {
1444 const sigset_t *sigmask;
1449 sys_sigsuspend(td, uap)
1451 struct sigsuspend_args *uap;
1456 error = copyin(uap->sigmask, &mask, sizeof(mask));
1459 return (kern_sigsuspend(td, mask));
1463 kern_sigsuspend(struct thread *td, sigset_t mask)
1465 struct proc *p = td->td_proc;
1469 * When returning from sigsuspend, we want
1470 * the old mask to be restored after the
1471 * signal handler has finished. Thus, we
1472 * save it here and mark the sigacts structure
1476 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1477 SIGPROCMASK_PROC_LOCKED);
1478 td->td_pflags |= TDP_OLDMASK;
1481 * Process signals now. Otherwise, we can get spurious wakeup
1482 * due to signal entered process queue, but delivered to other
1483 * thread. But sigsuspend should return only on signal
1486 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1487 for (has_sig = 0; !has_sig;) {
1488 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1491 thread_suspend_check(0);
1492 mtx_lock(&p->p_sigacts->ps_mtx);
1493 while ((sig = cursig(td)) != 0)
1494 has_sig += postsig(sig);
1495 mtx_unlock(&p->p_sigacts->ps_mtx);
1498 td->td_errno = EINTR;
1499 td->td_pflags |= TDP_NERRNO;
1500 return (EJUSTRETURN);
1503 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1505 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1506 * convention: libc stub passes mask, not pointer, to save a copyin.
1508 #ifndef _SYS_SYSPROTO_H_
1509 struct osigsuspend_args {
1515 osigsuspend(td, uap)
1517 struct osigsuspend_args *uap;
1521 OSIG2SIG(uap->mask, mask);
1522 return (kern_sigsuspend(td, mask));
1524 #endif /* COMPAT_43 */
1526 #if defined(COMPAT_43)
1527 #ifndef _SYS_SYSPROTO_H_
1528 struct osigstack_args {
1529 struct sigstack *nss;
1530 struct sigstack *oss;
1537 register struct osigstack_args *uap;
1539 struct sigstack nss, oss;
1542 if (uap->nss != NULL) {
1543 error = copyin(uap->nss, &nss, sizeof(nss));
1547 oss.ss_sp = td->td_sigstk.ss_sp;
1548 oss.ss_onstack = sigonstack(cpu_getstack(td));
1549 if (uap->nss != NULL) {
1550 td->td_sigstk.ss_sp = nss.ss_sp;
1551 td->td_sigstk.ss_size = 0;
1552 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1553 td->td_pflags |= TDP_ALTSTACK;
1555 if (uap->oss != NULL)
1556 error = copyout(&oss, uap->oss, sizeof(oss));
1560 #endif /* COMPAT_43 */
1562 #ifndef _SYS_SYSPROTO_H_
1563 struct sigaltstack_args {
1570 sys_sigaltstack(td, uap)
1572 register struct sigaltstack_args *uap;
1577 if (uap->ss != NULL) {
1578 error = copyin(uap->ss, &ss, sizeof(ss));
1582 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1583 (uap->oss != NULL) ? &oss : NULL);
1586 if (uap->oss != NULL)
1587 error = copyout(&oss, uap->oss, sizeof(stack_t));
1592 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1594 struct proc *p = td->td_proc;
1597 oonstack = sigonstack(cpu_getstack(td));
1600 *oss = td->td_sigstk;
1601 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1602 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1608 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1610 if (!(ss->ss_flags & SS_DISABLE)) {
1611 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1614 td->td_sigstk = *ss;
1615 td->td_pflags |= TDP_ALTSTACK;
1617 td->td_pflags &= ~TDP_ALTSTACK;
1624 * Common code for kill process group/broadcast kill.
1625 * cp is calling process.
1628 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1640 sx_slock(&allproc_lock);
1641 FOREACH_PROC_IN_SYSTEM(p) {
1643 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1644 p == td->td_proc || p->p_state == PRS_NEW) {
1648 err = p_cansignal(td, p, sig);
1651 pksignal(p, sig, ksi);
1654 else if (ret == ESRCH)
1658 sx_sunlock(&allproc_lock);
1660 sx_slock(&proctree_lock);
1663 * zero pgid means send to my process group.
1665 pgrp = td->td_proc->p_pgrp;
1668 pgrp = pgfind(pgid);
1670 sx_sunlock(&proctree_lock);
1674 sx_sunlock(&proctree_lock);
1675 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1677 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1678 p->p_state == PRS_NEW) {
1682 err = p_cansignal(td, p, sig);
1685 pksignal(p, sig, ksi);
1688 else if (ret == ESRCH)
1697 #ifndef _SYS_SYSPROTO_H_
1705 sys_kill(struct thread *td, struct kill_args *uap)
1712 * A process in capability mode can send signals only to himself.
1713 * The main rationale behind this is that abort(3) is implemented as
1714 * kill(getpid(), SIGABRT).
1716 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1719 AUDIT_ARG_SIGNUM(uap->signum);
1720 AUDIT_ARG_PID(uap->pid);
1721 if ((u_int)uap->signum > _SIG_MAXSIG)
1724 ksiginfo_init(&ksi);
1725 ksi.ksi_signo = uap->signum;
1726 ksi.ksi_code = SI_USER;
1727 ksi.ksi_pid = td->td_proc->p_pid;
1728 ksi.ksi_uid = td->td_ucred->cr_ruid;
1731 /* kill single process */
1732 if ((p = pfind(uap->pid)) == NULL) {
1733 if ((p = zpfind(uap->pid)) == NULL)
1736 AUDIT_ARG_PROCESS(p);
1737 error = p_cansignal(td, p, uap->signum);
1738 if (error == 0 && uap->signum)
1739 pksignal(p, uap->signum, &ksi);
1744 case -1: /* broadcast signal */
1745 return (killpg1(td, uap->signum, 0, 1, &ksi));
1746 case 0: /* signal own process group */
1747 return (killpg1(td, uap->signum, 0, 0, &ksi));
1748 default: /* negative explicit process group */
1749 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1757 struct pdkill_args *uap;
1761 cap_rights_t rights;
1764 AUDIT_ARG_SIGNUM(uap->signum);
1765 AUDIT_ARG_FD(uap->fd);
1766 if ((u_int)uap->signum > _SIG_MAXSIG)
1769 error = procdesc_find(td, uap->fd,
1770 cap_rights_init(&rights, CAP_PDKILL), &p);
1773 AUDIT_ARG_PROCESS(p);
1774 error = p_cansignal(td, p, uap->signum);
1775 if (error == 0 && uap->signum)
1776 kern_psignal(p, uap->signum);
1784 #if defined(COMPAT_43)
1785 #ifndef _SYS_SYSPROTO_H_
1786 struct okillpg_args {
1793 okillpg(struct thread *td, struct okillpg_args *uap)
1797 AUDIT_ARG_SIGNUM(uap->signum);
1798 AUDIT_ARG_PID(uap->pgid);
1799 if ((u_int)uap->signum > _SIG_MAXSIG)
1802 ksiginfo_init(&ksi);
1803 ksi.ksi_signo = uap->signum;
1804 ksi.ksi_code = SI_USER;
1805 ksi.ksi_pid = td->td_proc->p_pid;
1806 ksi.ksi_uid = td->td_ucred->cr_ruid;
1807 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1809 #endif /* COMPAT_43 */
1811 #ifndef _SYS_SYSPROTO_H_
1812 struct sigqueue_args {
1815 /* union sigval */ void *value;
1819 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1825 if ((u_int)uap->signum > _SIG_MAXSIG)
1829 * Specification says sigqueue can only send signal to
1835 if ((p = pfind(uap->pid)) == NULL) {
1836 if ((p = zpfind(uap->pid)) == NULL)
1839 error = p_cansignal(td, p, uap->signum);
1840 if (error == 0 && uap->signum != 0) {
1841 ksiginfo_init(&ksi);
1842 ksi.ksi_flags = KSI_SIGQ;
1843 ksi.ksi_signo = uap->signum;
1844 ksi.ksi_code = SI_QUEUE;
1845 ksi.ksi_pid = td->td_proc->p_pid;
1846 ksi.ksi_uid = td->td_ucred->cr_ruid;
1847 ksi.ksi_value.sival_ptr = uap->value;
1848 error = pksignal(p, ksi.ksi_signo, &ksi);
1855 * Send a signal to a process group.
1858 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1863 sx_slock(&proctree_lock);
1864 pgrp = pgfind(pgid);
1865 sx_sunlock(&proctree_lock);
1867 pgsignal(pgrp, sig, 0, ksi);
1874 * Send a signal to a process group. If checktty is 1,
1875 * limit to members which have a controlling terminal.
1878 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1883 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1884 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1886 if (p->p_state == PRS_NORMAL &&
1887 (checkctty == 0 || p->p_flag & P_CONTROLT))
1888 pksignal(p, sig, ksi);
1895 * Send a signal caused by a trap to the current thread. If it will be
1896 * caught immediately, deliver it with correct code. Otherwise, post it
1900 trapsignal(struct thread *td, ksiginfo_t *ksi)
1909 sig = ksi->ksi_signo;
1910 code = ksi->ksi_code;
1911 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1915 mtx_lock(&ps->ps_mtx);
1916 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1917 !SIGISMEMBER(td->td_sigmask, sig)) {
1918 td->td_ru.ru_nsignals++;
1920 if (KTRPOINT(curthread, KTR_PSIG))
1921 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1922 &td->td_sigmask, code);
1924 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1925 ksi, &td->td_sigmask);
1926 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1927 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1928 SIGADDSET(mask, sig);
1929 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1930 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1931 if (SIGISMEMBER(ps->ps_sigreset, sig))
1933 mtx_unlock(&ps->ps_mtx);
1936 * Avoid a possible infinite loop if the thread
1937 * masking the signal or process is ignoring the
1940 if (kern_forcesigexit &&
1941 (SIGISMEMBER(td->td_sigmask, sig) ||
1942 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1943 SIGDELSET(td->td_sigmask, sig);
1944 SIGDELSET(ps->ps_sigcatch, sig);
1945 SIGDELSET(ps->ps_sigignore, sig);
1946 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1948 mtx_unlock(&ps->ps_mtx);
1949 p->p_code = code; /* XXX for core dump/debugger */
1950 p->p_sig = sig; /* XXX to verify code */
1951 tdsendsignal(p, td, sig, ksi);
1956 static struct thread *
1957 sigtd(struct proc *p, int sig, int prop)
1959 struct thread *td, *signal_td;
1961 PROC_LOCK_ASSERT(p, MA_OWNED);
1964 * Check if current thread can handle the signal without
1965 * switching context to another thread.
1967 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1970 FOREACH_THREAD_IN_PROC(p, td) {
1971 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1976 if (signal_td == NULL)
1977 signal_td = FIRST_THREAD_IN_PROC(p);
1982 * Send the signal to the process. If the signal has an action, the action
1983 * is usually performed by the target process rather than the caller; we add
1984 * the signal to the set of pending signals for the process.
1987 * o When a stop signal is sent to a sleeping process that takes the
1988 * default action, the process is stopped without awakening it.
1989 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1990 * regardless of the signal action (eg, blocked or ignored).
1992 * Other ignored signals are discarded immediately.
1994 * NB: This function may be entered from the debugger via the "kill" DDB
1995 * command. There is little that can be done to mitigate the possibly messy
1996 * side effects of this unwise possibility.
1999 kern_psignal(struct proc *p, int sig)
2003 ksiginfo_init(&ksi);
2004 ksi.ksi_signo = sig;
2005 ksi.ksi_code = SI_KERNEL;
2006 (void) tdsendsignal(p, NULL, sig, &ksi);
2010 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2013 return (tdsendsignal(p, NULL, sig, ksi));
2016 /* Utility function for finding a thread to send signal event to. */
2018 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2022 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2023 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2035 tdsignal(struct thread *td, int sig)
2039 ksiginfo_init(&ksi);
2040 ksi.ksi_signo = sig;
2041 ksi.ksi_code = SI_KERNEL;
2042 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2046 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2049 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2053 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2056 sigqueue_t *sigqueue;
2063 MPASS(td == NULL || p == td->td_proc);
2064 PROC_LOCK_ASSERT(p, MA_OWNED);
2066 if (!_SIG_VALID(sig))
2067 panic("%s(): invalid signal %d", __func__, sig);
2069 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2072 * IEEE Std 1003.1-2001: return success when killing a zombie.
2074 if (p->p_state == PRS_ZOMBIE) {
2075 if (ksi && (ksi->ksi_flags & KSI_INS))
2076 ksiginfo_tryfree(ksi);
2081 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2082 prop = sigprop(sig);
2085 td = sigtd(p, sig, prop);
2086 sigqueue = &p->p_sigqueue;
2088 sigqueue = &td->td_sigqueue;
2090 SDT_PROBE(proc, kernel, , signal__send, td, p, sig, 0, 0 );
2093 * If the signal is being ignored,
2094 * then we forget about it immediately.
2095 * (Note: we don't set SIGCONT in ps_sigignore,
2096 * and if it is set to SIG_IGN,
2097 * action will be SIG_DFL here.)
2099 mtx_lock(&ps->ps_mtx);
2100 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2101 SDT_PROBE(proc, kernel, , signal__discard, td, p, sig, 0, 0 );
2103 mtx_unlock(&ps->ps_mtx);
2104 if (ksi && (ksi->ksi_flags & KSI_INS))
2105 ksiginfo_tryfree(ksi);
2108 if (SIGISMEMBER(td->td_sigmask, sig))
2110 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2114 if (SIGISMEMBER(ps->ps_sigintr, sig))
2118 mtx_unlock(&ps->ps_mtx);
2121 sigqueue_delete_stopmask_proc(p);
2122 else if (prop & SA_STOP) {
2124 * If sending a tty stop signal to a member of an orphaned
2125 * process group, discard the signal here if the action
2126 * is default; don't stop the process below if sleeping,
2127 * and don't clear any pending SIGCONT.
2129 if ((prop & SA_TTYSTOP) &&
2130 (p->p_pgrp->pg_jobc == 0) &&
2131 (action == SIG_DFL)) {
2132 if (ksi && (ksi->ksi_flags & KSI_INS))
2133 ksiginfo_tryfree(ksi);
2136 sigqueue_delete_proc(p, SIGCONT);
2137 if (p->p_flag & P_CONTINUED) {
2138 p->p_flag &= ~P_CONTINUED;
2139 PROC_LOCK(p->p_pptr);
2140 sigqueue_take(p->p_ksi);
2141 PROC_UNLOCK(p->p_pptr);
2145 ret = sigqueue_add(sigqueue, sig, ksi);
2150 * Defer further processing for signals which are held,
2151 * except that stopped processes must be continued by SIGCONT.
2153 if (action == SIG_HOLD &&
2154 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2157 * SIGKILL: Remove procfs STOPEVENTs.
2159 if (sig == SIGKILL) {
2160 /* from procfs_ioctl.c: PIOCBIC */
2162 /* from procfs_ioctl.c: PIOCCONT */
2167 * Some signals have a process-wide effect and a per-thread
2168 * component. Most processing occurs when the process next
2169 * tries to cross the user boundary, however there are some
2170 * times when processing needs to be done immediately, such as
2171 * waking up threads so that they can cross the user boundary.
2172 * We try to do the per-process part here.
2174 if (P_SHOULDSTOP(p)) {
2175 KASSERT(!(p->p_flag & P_WEXIT),
2176 ("signal to stopped but exiting process"));
2177 if (sig == SIGKILL) {
2179 * If traced process is already stopped,
2180 * then no further action is necessary.
2182 if (p->p_flag & P_TRACED)
2185 * SIGKILL sets process running.
2186 * It will die elsewhere.
2187 * All threads must be restarted.
2189 p->p_flag &= ~P_STOPPED_SIG;
2193 if (prop & SA_CONT) {
2195 * If traced process is already stopped,
2196 * then no further action is necessary.
2198 if (p->p_flag & P_TRACED)
2201 * If SIGCONT is default (or ignored), we continue the
2202 * process but don't leave the signal in sigqueue as
2203 * it has no further action. If SIGCONT is held, we
2204 * continue the process and leave the signal in
2205 * sigqueue. If the process catches SIGCONT, let it
2206 * handle the signal itself. If it isn't waiting on
2207 * an event, it goes back to run state.
2208 * Otherwise, process goes back to sleep state.
2210 p->p_flag &= ~P_STOPPED_SIG;
2212 if (p->p_numthreads == p->p_suspcount) {
2214 p->p_flag |= P_CONTINUED;
2215 p->p_xstat = SIGCONT;
2216 PROC_LOCK(p->p_pptr);
2217 childproc_continued(p);
2218 PROC_UNLOCK(p->p_pptr);
2221 if (action == SIG_DFL) {
2222 thread_unsuspend(p);
2224 sigqueue_delete(sigqueue, sig);
2227 if (action == SIG_CATCH) {
2229 * The process wants to catch it so it needs
2230 * to run at least one thread, but which one?
2236 * The signal is not ignored or caught.
2238 thread_unsuspend(p);
2243 if (prop & SA_STOP) {
2245 * If traced process is already stopped,
2246 * then no further action is necessary.
2248 if (p->p_flag & P_TRACED)
2251 * Already stopped, don't need to stop again
2252 * (If we did the shell could get confused).
2253 * Just make sure the signal STOP bit set.
2255 p->p_flag |= P_STOPPED_SIG;
2256 sigqueue_delete(sigqueue, sig);
2261 * All other kinds of signals:
2262 * If a thread is sleeping interruptibly, simulate a
2263 * wakeup so that when it is continued it will be made
2264 * runnable and can look at the signal. However, don't make
2265 * the PROCESS runnable, leave it stopped.
2266 * It may run a bit until it hits a thread_suspend_check().
2271 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2272 wakeup_swapper = sleepq_abort(td, intrval);
2279 * Mutexes are short lived. Threads waiting on them will
2280 * hit thread_suspend_check() soon.
2282 } else if (p->p_state == PRS_NORMAL) {
2283 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2284 tdsigwakeup(td, sig, action, intrval);
2288 MPASS(action == SIG_DFL);
2290 if (prop & SA_STOP) {
2291 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2293 p->p_flag |= P_STOPPED_SIG;
2296 sig_suspend_threads(td, p, 1);
2297 if (p->p_numthreads == p->p_suspcount) {
2299 * only thread sending signal to another
2300 * process can reach here, if thread is sending
2301 * signal to its process, because thread does
2302 * not suspend itself here, p_numthreads
2303 * should never be equal to p_suspcount.
2307 sigqueue_delete_proc(p, p->p_xstat);
2313 /* Not in "NORMAL" state. discard the signal. */
2314 sigqueue_delete(sigqueue, sig);
2319 * The process is not stopped so we need to apply the signal to all the
2323 tdsigwakeup(td, sig, action, intrval);
2325 thread_unsuspend(p);
2328 /* If we jump here, proc slock should not be owned. */
2329 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2334 * The force of a signal has been directed against a single
2335 * thread. We need to see what we can do about knocking it
2336 * out of any sleep it may be in etc.
2339 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2341 struct proc *p = td->td_proc;
2346 PROC_LOCK_ASSERT(p, MA_OWNED);
2347 prop = sigprop(sig);
2352 * Bring the priority of a thread up if we want it to get
2353 * killed in this lifetime.
2355 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2356 sched_prio(td, PUSER);
2357 if (TD_ON_SLEEPQ(td)) {
2359 * If thread is sleeping uninterruptibly
2360 * we can't interrupt the sleep... the signal will
2361 * be noticed when the process returns through
2362 * trap() or syscall().
2364 if ((td->td_flags & TDF_SINTR) == 0)
2367 * If SIGCONT is default (or ignored) and process is
2368 * asleep, we are finished; the process should not
2371 if ((prop & SA_CONT) && action == SIG_DFL) {
2374 sigqueue_delete(&p->p_sigqueue, sig);
2376 * It may be on either list in this state.
2377 * Remove from both for now.
2379 sigqueue_delete(&td->td_sigqueue, sig);
2384 * Don't awaken a sleeping thread for SIGSTOP if the
2385 * STOP signal is deferred.
2387 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2391 * Give low priority threads a better chance to run.
2393 if (td->td_priority > PUSER)
2394 sched_prio(td, PUSER);
2396 wakeup_swapper = sleepq_abort(td, intrval);
2399 * Other states do nothing with the signal immediately,
2400 * other than kicking ourselves if we are running.
2401 * It will either never be noticed, or noticed very soon.
2404 if (TD_IS_RUNNING(td) && td != curthread)
2416 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2420 PROC_LOCK_ASSERT(p, MA_OWNED);
2421 PROC_SLOCK_ASSERT(p, MA_OWNED);
2423 FOREACH_THREAD_IN_PROC(p, td2) {
2425 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2426 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2427 (td2->td_flags & TDF_SINTR)) {
2428 if (td2->td_flags & TDF_SBDRY) {
2430 * Once a thread is asleep with
2431 * TDF_SBDRY set, it should never
2432 * become suspended due to this check.
2434 KASSERT(!TD_IS_SUSPENDED(td2),
2435 ("thread with deferred stops suspended"));
2436 } else if (!TD_IS_SUSPENDED(td2)) {
2437 thread_suspend_one(td2);
2439 } else if (!TD_IS_SUSPENDED(td2)) {
2440 if (sending || td != td2)
2441 td2->td_flags |= TDF_ASTPENDING;
2443 if (TD_IS_RUNNING(td2) && td2 != td)
2444 forward_signal(td2);
2452 ptracestop(struct thread *td, int sig)
2454 struct proc *p = td->td_proc;
2456 PROC_LOCK_ASSERT(p, MA_OWNED);
2457 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2458 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2459 &p->p_mtx.lock_object, "Stopping for traced signal");
2461 td->td_dbgflags |= TDB_XSIG;
2464 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2465 if (p->p_flag & P_SINGLE_EXIT) {
2466 td->td_dbgflags &= ~TDB_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);
2478 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2479 td->td_dbgflags &= ~TDB_STOPATFORK;
2480 cv_broadcast(&p->p_dbgwait);
2483 thread_suspend_switch(td);
2484 if (p->p_xthread == td)
2485 p->p_xthread = NULL;
2486 if (!(p->p_flag & P_TRACED))
2488 if (td->td_dbgflags & TDB_SUSPEND) {
2489 if (p->p_flag & P_SINGLE_EXIT)
2495 return (td->td_xsig);
2499 reschedule_signals(struct proc *p, sigset_t block, int flags)
2505 PROC_LOCK_ASSERT(p, MA_OWNED);
2506 if (SIGISEMPTY(p->p_siglist))
2509 SIGSETAND(block, p->p_siglist);
2510 while ((sig = sig_ffs(&block)) != 0) {
2511 SIGDELSET(block, sig);
2512 td = sigtd(p, sig, 0);
2514 if (!(flags & SIGPROCMASK_PS_LOCKED))
2515 mtx_lock(&ps->ps_mtx);
2516 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2517 tdsigwakeup(td, sig, SIG_CATCH,
2518 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2520 if (!(flags & SIGPROCMASK_PS_LOCKED))
2521 mtx_unlock(&ps->ps_mtx);
2526 tdsigcleanup(struct thread *td)
2532 PROC_LOCK_ASSERT(p, MA_OWNED);
2534 sigqueue_flush(&td->td_sigqueue);
2535 if (p->p_numthreads == 1)
2539 * Since we cannot handle signals, notify signal post code
2540 * about this by filling the sigmask.
2542 * Also, if needed, wake up thread(s) that do not block the
2543 * same signals as the exiting thread, since the thread might
2544 * have been selected for delivery and woken up.
2546 SIGFILLSET(unblocked);
2547 SIGSETNAND(unblocked, td->td_sigmask);
2548 SIGFILLSET(td->td_sigmask);
2549 reschedule_signals(p, unblocked, 0);
2554 * Defer the delivery of SIGSTOP for the current thread. Returns true
2555 * if stops were deferred and false if they were already deferred.
2563 if (td->td_flags & TDF_SBDRY)
2566 td->td_flags |= TDF_SBDRY;
2572 * Permit the delivery of SIGSTOP for the current thread. This does
2573 * not immediately suspend if a stop was posted. Instead, the thread
2574 * will suspend either via ast() or a subsequent interruptible sleep.
2583 td->td_flags &= ~TDF_SBDRY;
2588 * If the current process has received a signal (should be caught or cause
2589 * termination, should interrupt current syscall), return the signal number.
2590 * Stop signals with default action are processed immediately, then cleared;
2591 * they aren't returned. This is checked after each entry to the system for
2592 * a syscall or trap (though this can usually be done without calling issignal
2593 * by checking the pending signal masks in cursig.) The normal call
2596 * while (sig = cursig(curthread))
2600 issignal(struct thread *td)
2604 struct sigqueue *queue;
2605 sigset_t sigpending;
2606 int sig, prop, newsig;
2610 mtx_assert(&ps->ps_mtx, MA_OWNED);
2611 PROC_LOCK_ASSERT(p, MA_OWNED);
2613 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2615 sigpending = td->td_sigqueue.sq_signals;
2616 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2617 SIGSETNAND(sigpending, td->td_sigmask);
2619 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2620 SIG_STOPSIGMASK(sigpending);
2621 if (SIGISEMPTY(sigpending)) /* no signal to send */
2623 sig = sig_ffs(&sigpending);
2625 if (p->p_stops & S_SIG) {
2626 mtx_unlock(&ps->ps_mtx);
2627 stopevent(p, S_SIG, sig);
2628 mtx_lock(&ps->ps_mtx);
2632 * We should see pending but ignored signals
2633 * only if P_TRACED was on when they were posted.
2635 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2636 sigqueue_delete(&td->td_sigqueue, sig);
2637 sigqueue_delete(&p->p_sigqueue, sig);
2640 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) {
2642 * If traced, always stop.
2643 * Remove old signal from queue before the stop.
2644 * XXX shrug off debugger, it causes siginfo to
2647 queue = &td->td_sigqueue;
2648 td->td_dbgksi.ksi_signo = 0;
2649 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2650 queue = &p->p_sigqueue;
2651 sigqueue_get(queue, sig, &td->td_dbgksi);
2654 mtx_unlock(&ps->ps_mtx);
2655 newsig = ptracestop(td, sig);
2656 mtx_lock(&ps->ps_mtx);
2658 if (sig != newsig) {
2661 * If parent wants us to take the signal,
2662 * then it will leave it in p->p_xstat;
2663 * otherwise we just look for signals again.
2670 * Put the new signal into td_sigqueue. If the
2671 * signal is being masked, look for other
2674 sigqueue_add(queue, sig, NULL);
2675 if (SIGISMEMBER(td->td_sigmask, sig))
2679 if (td->td_dbgksi.ksi_signo != 0) {
2680 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2681 if (sigqueue_add(&td->td_sigqueue, sig,
2682 &td->td_dbgksi) != 0)
2683 td->td_dbgksi.ksi_signo = 0;
2685 if (td->td_dbgksi.ksi_signo == 0)
2686 sigqueue_add(&td->td_sigqueue, sig,
2691 * If the traced bit got turned off, go back up
2692 * to the top to rescan signals. This ensures
2693 * that p_sig* and p_sigact are consistent.
2695 if ((p->p_flag & P_TRACED) == 0)
2699 prop = sigprop(sig);
2702 * Decide whether the signal should be returned.
2703 * Return the signal's number, or fall through
2704 * to clear it from the pending mask.
2706 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2708 case (intptr_t)SIG_DFL:
2710 * Don't take default actions on system processes.
2712 if (p->p_pid <= 1) {
2715 * Are you sure you want to ignore SIGSEGV
2718 printf("Process (pid %lu) got signal %d\n",
2719 (u_long)p->p_pid, sig);
2721 break; /* == ignore */
2724 * If there is a pending stop signal to process
2725 * with default action, stop here,
2726 * then clear the signal. However,
2727 * if process is member of an orphaned
2728 * process group, ignore tty stop signals.
2730 if (prop & SA_STOP) {
2731 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2732 (p->p_pgrp->pg_jobc == 0 &&
2734 break; /* == ignore */
2735 mtx_unlock(&ps->ps_mtx);
2736 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2737 &p->p_mtx.lock_object, "Catching SIGSTOP");
2738 p->p_flag |= P_STOPPED_SIG;
2741 sig_suspend_threads(td, p, 0);
2742 thread_suspend_switch(td);
2744 mtx_lock(&ps->ps_mtx);
2746 } else if (prop & SA_IGNORE) {
2748 * Except for SIGCONT, shouldn't get here.
2749 * Default action is to ignore; drop it.
2751 break; /* == ignore */
2756 case (intptr_t)SIG_IGN:
2758 * Masking above should prevent us ever trying
2759 * to take action on an ignored signal other
2760 * than SIGCONT, unless process is traced.
2762 if ((prop & SA_CONT) == 0 &&
2763 (p->p_flag & P_TRACED) == 0)
2764 printf("issignal\n");
2765 break; /* == ignore */
2769 * This signal has an action, let
2770 * postsig() process it.
2774 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2775 sigqueue_delete(&p->p_sigqueue, sig);
2781 thread_stopped(struct proc *p)
2785 PROC_LOCK_ASSERT(p, MA_OWNED);
2786 PROC_SLOCK_ASSERT(p, MA_OWNED);
2790 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2792 p->p_flag &= ~P_WAITED;
2793 PROC_LOCK(p->p_pptr);
2794 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2795 CLD_TRAPPED : CLD_STOPPED);
2796 PROC_UNLOCK(p->p_pptr);
2802 * Take the action for the specified signal
2803 * from the current set of pending signals.
2809 struct thread *td = curthread;
2810 register struct proc *p = td->td_proc;
2814 sigset_t returnmask, mask;
2816 KASSERT(sig != 0, ("postsig"));
2818 PROC_LOCK_ASSERT(p, MA_OWNED);
2820 mtx_assert(&ps->ps_mtx, MA_OWNED);
2821 ksiginfo_init(&ksi);
2822 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2823 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2825 ksi.ksi_signo = sig;
2826 if (ksi.ksi_code == SI_TIMER)
2827 itimer_accept(p, ksi.ksi_timerid, &ksi);
2828 action = ps->ps_sigact[_SIG_IDX(sig)];
2830 if (KTRPOINT(td, KTR_PSIG))
2831 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2832 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2834 if (p->p_stops & S_SIG) {
2835 mtx_unlock(&ps->ps_mtx);
2836 stopevent(p, S_SIG, sig);
2837 mtx_lock(&ps->ps_mtx);
2840 if (action == SIG_DFL) {
2842 * Default action, where the default is to kill
2843 * the process. (Other cases were ignored above.)
2845 mtx_unlock(&ps->ps_mtx);
2850 * If we get here, the signal must be caught.
2852 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2853 ("postsig action"));
2855 * Set the new mask value and also defer further
2856 * occurrences of this signal.
2858 * Special case: user has done a sigsuspend. Here the
2859 * current mask is not of interest, but rather the
2860 * mask from before the sigsuspend is what we want
2861 * restored after the signal processing is completed.
2863 if (td->td_pflags & TDP_OLDMASK) {
2864 returnmask = td->td_oldsigmask;
2865 td->td_pflags &= ~TDP_OLDMASK;
2867 returnmask = td->td_sigmask;
2869 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2870 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2871 SIGADDSET(mask, sig);
2872 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2873 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2875 if (SIGISMEMBER(ps->ps_sigreset, sig))
2877 td->td_ru.ru_nsignals++;
2878 if (p->p_sig == sig) {
2882 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2888 * Kill the current process for stated reason.
2896 PROC_LOCK_ASSERT(p, MA_OWNED);
2897 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2899 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2900 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2901 p->p_flag |= P_WKILLED;
2902 kern_psignal(p, SIGKILL);
2906 * Force the current process to exit with the specified signal, dumping core
2907 * if appropriate. We bypass the normal tests for masked and caught signals,
2908 * allowing unrecoverable failures to terminate the process without changing
2909 * signal state. Mark the accounting record with the signal termination.
2910 * If dumping core, save the signal number for the debugger. Calls exit and
2918 struct proc *p = td->td_proc;
2920 PROC_LOCK_ASSERT(p, MA_OWNED);
2921 p->p_acflag |= AXSIG;
2923 * We must be single-threading to generate a core dump. This
2924 * ensures that the registers in the core file are up-to-date.
2925 * Also, the ELF dump handler assumes that the thread list doesn't
2926 * change out from under it.
2928 * XXX If another thread attempts to single-thread before us
2929 * (e.g. via fork()), we won't get a dump at all.
2931 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2934 * Log signals which would cause core dumps
2935 * (Log as LOG_INFO to appease those who don't want
2937 * XXX : Todo, as well as euid, write out ruid too
2938 * Note that coredump() drops proc lock.
2940 if (coredump(td) == 0)
2942 if (kern_logsigexit)
2944 "pid %d (%s), uid %d: exited on signal %d%s\n",
2945 p->p_pid, p->p_comm,
2946 td->td_ucred ? td->td_ucred->cr_uid : -1,
2948 sig & WCOREFLAG ? " (core dumped)" : "");
2951 exit1(td, W_EXITCODE(0, sig));
2956 * Send queued SIGCHLD to parent when child process's state
2960 sigparent(struct proc *p, int reason, int status)
2962 PROC_LOCK_ASSERT(p, MA_OWNED);
2963 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2965 if (p->p_ksi != NULL) {
2966 p->p_ksi->ksi_signo = SIGCHLD;
2967 p->p_ksi->ksi_code = reason;
2968 p->p_ksi->ksi_status = status;
2969 p->p_ksi->ksi_pid = p->p_pid;
2970 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2971 if (KSI_ONQ(p->p_ksi))
2974 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2978 childproc_jobstate(struct proc *p, int reason, int sig)
2982 PROC_LOCK_ASSERT(p, MA_OWNED);
2983 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2986 * Wake up parent sleeping in kern_wait(), also send
2987 * SIGCHLD to parent, but SIGCHLD does not guarantee
2988 * that parent will awake, because parent may masked
2991 p->p_pptr->p_flag |= P_STATCHILD;
2994 ps = p->p_pptr->p_sigacts;
2995 mtx_lock(&ps->ps_mtx);
2996 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2997 mtx_unlock(&ps->ps_mtx);
2998 sigparent(p, reason, sig);
3000 mtx_unlock(&ps->ps_mtx);
3004 childproc_stopped(struct proc *p, int reason)
3006 /* p_xstat is a plain signal number, not a full wait() status here. */
3007 childproc_jobstate(p, reason, p->p_xstat);
3011 childproc_continued(struct proc *p)
3013 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3017 childproc_exited(struct proc *p)
3020 int xstat = p->p_xstat; /* convert to int */
3023 if (WCOREDUMP(xstat))
3024 reason = CLD_DUMPED, status = WTERMSIG(xstat);
3025 else if (WIFSIGNALED(xstat))
3026 reason = CLD_KILLED, status = WTERMSIG(xstat);
3028 reason = CLD_EXITED, status = WEXITSTATUS(xstat);
3030 * XXX avoid calling wakeup(p->p_pptr), the work is
3033 sigparent(p, reason, status);
3037 * We only have 1 character for the core count in the format
3038 * string, so the range will be 0-9
3040 #define MAX_NUM_CORES 10
3041 static int num_cores = 5;
3044 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3049 new_val = num_cores;
3050 error = sysctl_handle_int(oidp, &new_val, 0, req);
3051 if (error != 0 || req->newptr == NULL)
3053 if (new_val > MAX_NUM_CORES)
3054 new_val = MAX_NUM_CORES;
3057 num_cores = new_val;
3060 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3061 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3063 #if defined(COMPRESS_USER_CORES)
3064 int compress_user_cores = 1;
3065 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
3066 &compress_user_cores, 0, "Compression of user corefiles");
3068 int compress_user_cores_gzlevel = -1; /* default level */
3069 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
3070 &compress_user_cores_gzlevel, -1, "Corefile gzip compression level");
3072 #define GZ_SUFFIX ".gz"
3073 #define GZ_SUFFIX_LEN 3
3076 static char corefilename[MAXPATHLEN] = {"%N.core"};
3077 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3078 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3079 sizeof(corefilename), "Process corefile name format string");
3082 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3083 * Expand the name described in corefilename, using name, uid, and pid
3084 * and open/create core file.
3085 * corefilename is a printf-like string, with three format specifiers:
3086 * %N name of process ("name")
3087 * %P process id (pid)
3089 * For example, "%N.core" is the default; they can be disabled completely
3090 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3091 * This is controlled by the sysctl variable kern.corefile (see above).
3094 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3095 int compress, struct vnode **vpp, char **namep)
3097 struct nameidata nd;
3100 char *hostname, *name;
3101 int indexpos, i, error, cmode, flags, oflags;
3104 format = corefilename;
3105 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3107 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3108 for (i = 0; format[i] != '\0'; i++) {
3109 switch (format[i]) {
3110 case '%': /* Format character */
3112 switch (format[i]) {
3114 sbuf_putc(&sb, '%');
3116 case 'H': /* hostname */
3117 if (hostname == NULL) {
3118 hostname = malloc(MAXHOSTNAMELEN,
3121 getcredhostname(td->td_ucred, hostname,
3123 sbuf_printf(&sb, "%s", hostname);
3125 case 'I': /* autoincrementing index */
3126 sbuf_printf(&sb, "0");
3127 indexpos = sbuf_len(&sb) - 1;
3129 case 'N': /* process name */
3130 sbuf_printf(&sb, "%s", comm);
3132 case 'P': /* process id */
3133 sbuf_printf(&sb, "%u", pid);
3135 case 'U': /* user id */
3136 sbuf_printf(&sb, "%u", uid);
3140 "Unknown format character %c in "
3141 "corename `%s'\n", format[i], format);
3146 sbuf_putc(&sb, format[i]);
3150 free(hostname, M_TEMP);
3151 #ifdef COMPRESS_USER_CORES
3153 sbuf_printf(&sb, GZ_SUFFIX);
3155 if (sbuf_error(&sb) != 0) {
3156 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3157 "long\n", (long)pid, comm, (u_long)uid);
3165 cmode = S_IRUSR | S_IWUSR;
3166 oflags = VN_OPEN_NOAUDIT | (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3169 * If the core format has a %I in it, then we need to check
3170 * for existing corefiles before returning a name.
3171 * To do this we iterate over 0..num_cores to find a
3172 * non-existing core file name to use.
3174 if (indexpos != -1) {
3175 for (i = 0; i < num_cores; i++) {
3176 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3177 name[indexpos] = '0' + i;
3178 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3179 error = vn_open_cred(&nd, &flags, cmode, oflags,
3180 td->td_ucred, NULL);
3182 if (error == EEXIST)
3185 "pid %d (%s), uid (%u): Path `%s' failed "
3186 "on initial open test, error = %d\n",
3187 pid, comm, uid, name, error);
3193 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3194 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3195 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3199 audit_proc_coredump(td, name, error);
3204 NDFREE(&nd, NDF_ONLY_PNBUF);
3211 * Dump a process' core. The main routine does some
3212 * policy checking, and creates the name of the coredump;
3213 * then it passes on a vnode and a size limit to the process-specific
3214 * coredump routine if there is one; if there _is not_ one, it returns
3215 * ENOSYS; otherwise it returns the error from the process-specific routine.
3219 coredump(struct thread *td)
3221 struct proc *p = td->td_proc;
3222 struct ucred *cred = td->td_ucred;
3226 int error, error1, locked;
3228 char *name; /* name of corefile */
3232 #ifdef COMPRESS_USER_CORES
3233 compress = compress_user_cores;
3237 PROC_LOCK_ASSERT(p, MA_OWNED);
3238 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3239 _STOPEVENT(p, S_CORE, 0);
3241 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0)) {
3247 * Note that the bulk of limit checking is done after
3248 * the corefile is created. The exception is if the limit
3249 * for corefiles is 0, in which case we don't bother
3250 * creating the corefile at all. This layout means that
3251 * a corefile is truncated instead of not being created,
3252 * if it is larger than the limit.
3254 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3255 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3262 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress,
3267 /* Don't dump to non-regular files or files with links. */
3268 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3269 vattr.va_nlink != 1) {
3276 lf.l_whence = SEEK_SET;
3279 lf.l_type = F_WRLCK;
3280 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3282 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3283 lf.l_type = F_UNLCK;
3285 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3286 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3288 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3296 if (set_core_nodump_flag)
3297 vattr.va_flags = UF_NODUMP;
3298 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3299 VOP_SETATTR(vp, &vattr, cred);
3301 vn_finished_write(mp);
3303 p->p_acflag |= ACORE;
3306 if (p->p_sysent->sv_coredump != NULL) {
3307 error = p->p_sysent->sv_coredump(td, vp, limit,
3308 compress ? IMGACT_CORE_COMPRESS : 0);
3314 lf.l_type = F_UNLCK;
3315 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3318 error1 = vn_close(vp, FWRITE, cred, td);
3323 audit_proc_coredump(td, name, error);
3330 * Nonexistent system call-- signal process (may want to handle it). Flag
3331 * error in case process won't see signal immediately (blocked or ignored).
3333 #ifndef _SYS_SYSPROTO_H_
3342 struct nosys_args *args;
3344 struct proc *p = td->td_proc;
3347 tdsignal(td, SIGSYS);
3353 * Send a SIGIO or SIGURG signal to a process or process group using stored
3354 * credentials rather than those of the current process.
3357 pgsigio(sigiop, sig, checkctty)
3358 struct sigio **sigiop;
3362 struct sigio *sigio;
3364 ksiginfo_init(&ksi);
3365 ksi.ksi_signo = sig;
3366 ksi.ksi_code = SI_KERNEL;
3370 if (sigio == NULL) {
3374 if (sigio->sio_pgid > 0) {
3375 PROC_LOCK(sigio->sio_proc);
3376 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3377 kern_psignal(sigio->sio_proc, sig);
3378 PROC_UNLOCK(sigio->sio_proc);
3379 } else if (sigio->sio_pgid < 0) {
3382 PGRP_LOCK(sigio->sio_pgrp);
3383 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3385 if (p->p_state == PRS_NORMAL &&
3386 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3387 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3388 kern_psignal(p, sig);
3391 PGRP_UNLOCK(sigio->sio_pgrp);
3397 filt_sigattach(struct knote *kn)
3399 struct proc *p = curproc;
3401 kn->kn_ptr.p_proc = p;
3402 kn->kn_flags |= EV_CLEAR; /* automatically set */
3404 knlist_add(&p->p_klist, kn, 0);
3410 filt_sigdetach(struct knote *kn)
3412 struct proc *p = kn->kn_ptr.p_proc;
3414 knlist_remove(&p->p_klist, kn, 0);
3418 * signal knotes are shared with proc knotes, so we apply a mask to
3419 * the hint in order to differentiate them from process hints. This
3420 * could be avoided by using a signal-specific knote list, but probably
3421 * isn't worth the trouble.
3424 filt_signal(struct knote *kn, long hint)
3427 if (hint & NOTE_SIGNAL) {
3428 hint &= ~NOTE_SIGNAL;
3430 if (kn->kn_id == hint)
3433 return (kn->kn_data != 0);
3441 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3443 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3448 sigacts_free(struct sigacts *ps)
3451 if (refcount_release(&ps->ps_refcnt) == 0)
3453 mtx_destroy(&ps->ps_mtx);
3454 free(ps, M_SUBPROC);
3458 sigacts_hold(struct sigacts *ps)
3461 refcount_acquire(&ps->ps_refcnt);
3466 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3469 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3470 mtx_lock(&src->ps_mtx);
3471 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3472 mtx_unlock(&src->ps_mtx);
3476 sigacts_shared(struct sigacts *ps)
3479 return (ps->ps_refcnt > 1);