2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
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9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
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13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
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20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
42 #include "opt_ktrace.h"
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
51 #include <sys/capsicum.h>
52 #include <sys/compressor.h>
53 #include <sys/condvar.h>
54 #include <sys/event.h>
55 #include <sys/fcntl.h>
56 #include <sys/imgact.h>
57 #include <sys/kernel.h>
59 #include <sys/ktrace.h>
61 #include <sys/malloc.h>
62 #include <sys/mutex.h>
63 #include <sys/refcount.h>
64 #include <sys/namei.h>
66 #include <sys/procdesc.h>
67 #include <sys/posix4.h>
68 #include <sys/pioctl.h>
69 #include <sys/racct.h>
70 #include <sys/resourcevar.h>
73 #include <sys/sleepqueue.h>
77 #include <sys/syscallsubr.h>
78 #include <sys/sysctl.h>
79 #include <sys/sysent.h>
80 #include <sys/syslog.h>
81 #include <sys/sysproto.h>
82 #include <sys/timers.h>
83 #include <sys/unistd.h>
86 #include <vm/vm_extern.h>
91 #include <machine/cpu.h>
93 #include <security/audit/audit.h>
95 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
97 SDT_PROVIDER_DECLARE(proc);
98 SDT_PROBE_DEFINE3(proc, , , signal__send,
99 "struct thread *", "struct proc *", "int");
100 SDT_PROBE_DEFINE2(proc, , , signal__clear,
101 "int", "ksiginfo_t *");
102 SDT_PROBE_DEFINE3(proc, , , signal__discard,
103 "struct thread *", "struct proc *", "int");
105 static int coredump(struct thread *);
106 static int killpg1(struct thread *td, int sig, int pgid, int all,
108 static int issignal(struct thread *td);
109 static int sigprop(int sig);
110 static void tdsigwakeup(struct thread *, int, sig_t, int);
111 static int sig_suspend_threads(struct thread *, struct proc *, int);
112 static int filt_sigattach(struct knote *kn);
113 static void filt_sigdetach(struct knote *kn);
114 static int filt_signal(struct knote *kn, long hint);
115 static struct thread *sigtd(struct proc *p, int sig, int prop);
116 static void sigqueue_start(void);
118 static uma_zone_t ksiginfo_zone = NULL;
119 struct filterops sig_filtops = {
121 .f_attach = filt_sigattach,
122 .f_detach = filt_sigdetach,
123 .f_event = filt_signal,
126 static int kern_logsigexit = 1;
127 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
129 "Log processes quitting on abnormal signals to syslog(3)");
131 static int kern_forcesigexit = 1;
132 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
133 &kern_forcesigexit, 0, "Force trap signal to be handled");
135 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
136 "POSIX real time signal");
138 static int max_pending_per_proc = 128;
139 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
140 &max_pending_per_proc, 0, "Max pending signals per proc");
142 static int preallocate_siginfo = 1024;
143 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
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 static int kern_lognosys = 0;
155 SYSCTL_INT(_kern, OID_AUTO, lognosys, CTLFLAG_RWTUN, &kern_lognosys, 0,
156 "Log invalid syscalls");
158 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
161 * Policy -- Can ucred cr1 send SIGIO to process cr2?
162 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
163 * in the right situations.
165 #define CANSIGIO(cr1, cr2) \
166 ((cr1)->cr_uid == 0 || \
167 (cr1)->cr_ruid == (cr2)->cr_ruid || \
168 (cr1)->cr_uid == (cr2)->cr_ruid || \
169 (cr1)->cr_ruid == (cr2)->cr_uid || \
170 (cr1)->cr_uid == (cr2)->cr_uid)
172 static int sugid_coredump;
173 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
174 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
176 static int capmode_coredump;
177 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
178 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
180 static int do_coredump = 1;
181 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
182 &do_coredump, 0, "Enable/Disable coredumps");
184 static int set_core_nodump_flag = 0;
185 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
186 0, "Enable setting the NODUMP flag on coredump files");
188 static int coredump_devctl = 0;
189 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
190 0, "Generate a devctl notification when processes coredump");
193 * Signal properties and actions.
194 * The array below categorizes the signals and their default actions
195 * according to the following properties:
197 #define SIGPROP_KILL 0x01 /* terminates process by default */
198 #define SIGPROP_CORE 0x02 /* ditto and coredumps */
199 #define SIGPROP_STOP 0x04 /* suspend process */
200 #define SIGPROP_TTYSTOP 0x08 /* ditto, from tty */
201 #define SIGPROP_IGNORE 0x10 /* ignore by default */
202 #define SIGPROP_CONT 0x20 /* continue if suspended */
203 #define SIGPROP_CANTMASK 0x40 /* non-maskable, catchable */
205 static int sigproptbl[NSIG] = {
206 [SIGHUP] = SIGPROP_KILL,
207 [SIGINT] = SIGPROP_KILL,
208 [SIGQUIT] = SIGPROP_KILL | SIGPROP_CORE,
209 [SIGILL] = SIGPROP_KILL | SIGPROP_CORE,
210 [SIGTRAP] = SIGPROP_KILL | SIGPROP_CORE,
211 [SIGABRT] = SIGPROP_KILL | SIGPROP_CORE,
212 [SIGEMT] = SIGPROP_KILL | SIGPROP_CORE,
213 [SIGFPE] = SIGPROP_KILL | SIGPROP_CORE,
214 [SIGKILL] = SIGPROP_KILL,
215 [SIGBUS] = SIGPROP_KILL | SIGPROP_CORE,
216 [SIGSEGV] = SIGPROP_KILL | SIGPROP_CORE,
217 [SIGSYS] = SIGPROP_KILL | SIGPROP_CORE,
218 [SIGPIPE] = SIGPROP_KILL,
219 [SIGALRM] = SIGPROP_KILL,
220 [SIGTERM] = SIGPROP_KILL,
221 [SIGURG] = SIGPROP_IGNORE,
222 [SIGSTOP] = SIGPROP_STOP,
223 [SIGTSTP] = SIGPROP_STOP | SIGPROP_TTYSTOP,
224 [SIGCONT] = SIGPROP_IGNORE | SIGPROP_CONT,
225 [SIGCHLD] = SIGPROP_IGNORE,
226 [SIGTTIN] = SIGPROP_STOP | SIGPROP_TTYSTOP,
227 [SIGTTOU] = SIGPROP_STOP | SIGPROP_TTYSTOP,
228 [SIGIO] = SIGPROP_IGNORE,
229 [SIGXCPU] = SIGPROP_KILL,
230 [SIGXFSZ] = SIGPROP_KILL,
231 [SIGVTALRM] = SIGPROP_KILL,
232 [SIGPROF] = SIGPROP_KILL,
233 [SIGWINCH] = SIGPROP_IGNORE,
234 [SIGINFO] = SIGPROP_IGNORE,
235 [SIGUSR1] = SIGPROP_KILL,
236 [SIGUSR2] = SIGPROP_KILL,
239 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
244 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
245 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
246 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
247 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
248 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
249 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
253 ksiginfo_alloc(int wait)
260 if (ksiginfo_zone != NULL)
261 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
266 ksiginfo_free(ksiginfo_t *ksi)
268 uma_zfree(ksiginfo_zone, ksi);
272 ksiginfo_tryfree(ksiginfo_t *ksi)
274 if (!(ksi->ksi_flags & KSI_EXT)) {
275 uma_zfree(ksiginfo_zone, ksi);
282 sigqueue_init(sigqueue_t *list, struct proc *p)
284 SIGEMPTYSET(list->sq_signals);
285 SIGEMPTYSET(list->sq_kill);
286 SIGEMPTYSET(list->sq_ptrace);
287 TAILQ_INIT(&list->sq_list);
289 list->sq_flags = SQ_INIT;
293 * Get a signal's ksiginfo.
295 * 0 - signal not found
296 * others - signal number
299 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
301 struct proc *p = sq->sq_proc;
302 struct ksiginfo *ksi, *next;
305 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
307 if (!SIGISMEMBER(sq->sq_signals, signo))
310 if (SIGISMEMBER(sq->sq_ptrace, signo)) {
312 SIGDELSET(sq->sq_ptrace, signo);
313 si->ksi_flags |= KSI_PTRACE;
315 if (SIGISMEMBER(sq->sq_kill, signo)) {
318 SIGDELSET(sq->sq_kill, signo);
321 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
322 if (ksi->ksi_signo == signo) {
324 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
325 ksi->ksi_sigq = NULL;
326 ksiginfo_copy(ksi, si);
327 if (ksiginfo_tryfree(ksi) && p != NULL)
336 SIGDELSET(sq->sq_signals, signo);
337 si->ksi_signo = signo;
342 sigqueue_take(ksiginfo_t *ksi)
348 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
352 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
353 ksi->ksi_sigq = NULL;
354 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
357 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
358 kp = TAILQ_NEXT(kp, ksi_link)) {
359 if (kp->ksi_signo == ksi->ksi_signo)
362 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) &&
363 !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo))
364 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
368 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
370 struct proc *p = sq->sq_proc;
371 struct ksiginfo *ksi;
374 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
377 * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path
380 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
381 SIGADDSET(sq->sq_kill, signo);
385 /* directly insert the ksi, don't copy it */
386 if (si->ksi_flags & KSI_INS) {
387 if (si->ksi_flags & KSI_HEAD)
388 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
390 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
395 if (__predict_false(ksiginfo_zone == NULL)) {
396 SIGADDSET(sq->sq_kill, signo);
400 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
403 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
409 ksiginfo_copy(si, ksi);
410 ksi->ksi_signo = signo;
411 if (si->ksi_flags & KSI_HEAD)
412 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
414 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
419 if ((si->ksi_flags & KSI_PTRACE) != 0) {
420 SIGADDSET(sq->sq_ptrace, signo);
423 } else if ((si->ksi_flags & KSI_TRAP) != 0 ||
424 (si->ksi_flags & KSI_SIGQ) == 0) {
425 SIGADDSET(sq->sq_kill, signo);
433 SIGADDSET(sq->sq_signals, signo);
438 sigqueue_flush(sigqueue_t *sq)
440 struct proc *p = sq->sq_proc;
443 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
446 PROC_LOCK_ASSERT(p, MA_OWNED);
448 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
449 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
450 ksi->ksi_sigq = NULL;
451 if (ksiginfo_tryfree(ksi) && p != NULL)
455 SIGEMPTYSET(sq->sq_signals);
456 SIGEMPTYSET(sq->sq_kill);
457 SIGEMPTYSET(sq->sq_ptrace);
461 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
464 struct proc *p1, *p2;
465 ksiginfo_t *ksi, *next;
467 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
468 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
471 /* Move siginfo to target list */
472 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
473 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
474 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
477 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
484 /* Move pending bits to target list */
486 SIGSETAND(tmp, *set);
487 SIGSETOR(dst->sq_kill, tmp);
488 SIGSETNAND(src->sq_kill, tmp);
490 tmp = src->sq_ptrace;
491 SIGSETAND(tmp, *set);
492 SIGSETOR(dst->sq_ptrace, tmp);
493 SIGSETNAND(src->sq_ptrace, tmp);
495 tmp = src->sq_signals;
496 SIGSETAND(tmp, *set);
497 SIGSETOR(dst->sq_signals, tmp);
498 SIGSETNAND(src->sq_signals, tmp);
503 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
508 SIGADDSET(set, signo);
509 sigqueue_move_set(src, dst, &set);
514 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
516 struct proc *p = sq->sq_proc;
517 ksiginfo_t *ksi, *next;
519 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
521 /* Remove siginfo queue */
522 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
523 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
524 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
525 ksi->ksi_sigq = NULL;
526 if (ksiginfo_tryfree(ksi) && p != NULL)
530 SIGSETNAND(sq->sq_kill, *set);
531 SIGSETNAND(sq->sq_ptrace, *set);
532 SIGSETNAND(sq->sq_signals, *set);
536 sigqueue_delete(sigqueue_t *sq, int signo)
541 SIGADDSET(set, signo);
542 sigqueue_delete_set(sq, &set);
545 /* Remove a set of signals for a process */
547 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
552 PROC_LOCK_ASSERT(p, MA_OWNED);
554 sigqueue_init(&worklist, NULL);
555 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
557 FOREACH_THREAD_IN_PROC(p, td0)
558 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
560 sigqueue_flush(&worklist);
564 sigqueue_delete_proc(struct proc *p, int signo)
569 SIGADDSET(set, signo);
570 sigqueue_delete_set_proc(p, &set);
574 sigqueue_delete_stopmask_proc(struct proc *p)
579 SIGADDSET(set, SIGSTOP);
580 SIGADDSET(set, SIGTSTP);
581 SIGADDSET(set, SIGTTIN);
582 SIGADDSET(set, SIGTTOU);
583 sigqueue_delete_set_proc(p, &set);
587 * Determine signal that should be delivered to thread td, the current
588 * thread, 0 if none. If there is a pending stop signal with default
589 * action, the process stops in issignal().
592 cursig(struct thread *td)
594 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
595 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
596 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
597 return (SIGPENDING(td) ? issignal(td) : 0);
601 * Arrange for ast() to handle unmasked pending signals on return to user
602 * mode. This must be called whenever a signal is added to td_sigqueue or
603 * unmasked in td_sigmask.
606 signotify(struct thread *td)
609 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
611 if (SIGPENDING(td)) {
613 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
619 sigonstack(size_t sp)
621 struct thread *td = curthread;
623 return ((td->td_pflags & TDP_ALTSTACK) ?
624 #if defined(COMPAT_43)
625 ((td->td_sigstk.ss_size == 0) ?
626 (td->td_sigstk.ss_flags & SS_ONSTACK) :
627 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
629 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
638 if (sig > 0 && sig < nitems(sigproptbl))
639 return (sigproptbl[sig]);
644 sig_ffs(sigset_t *set)
648 for (i = 0; i < _SIG_WORDS; i++)
650 return (ffs(set->__bits[i]) + (i * 32));
655 sigact_flag_test(const struct sigaction *act, int flag)
659 * SA_SIGINFO is reset when signal disposition is set to
660 * ignore or default. Other flags are kept according to user
663 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
664 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
665 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
675 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
676 struct sigaction *oact, int flags)
679 struct proc *p = td->td_proc;
681 if (!_SIG_VALID(sig))
683 if (act != NULL && act->sa_handler != SIG_DFL &&
684 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
685 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
686 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
691 mtx_lock(&ps->ps_mtx);
693 memset(oact, 0, sizeof(*oact));
694 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
695 if (SIGISMEMBER(ps->ps_sigonstack, sig))
696 oact->sa_flags |= SA_ONSTACK;
697 if (!SIGISMEMBER(ps->ps_sigintr, sig))
698 oact->sa_flags |= SA_RESTART;
699 if (SIGISMEMBER(ps->ps_sigreset, sig))
700 oact->sa_flags |= SA_RESETHAND;
701 if (SIGISMEMBER(ps->ps_signodefer, sig))
702 oact->sa_flags |= SA_NODEFER;
703 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
704 oact->sa_flags |= SA_SIGINFO;
706 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
708 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
709 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
710 oact->sa_flags |= SA_NOCLDSTOP;
711 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
712 oact->sa_flags |= SA_NOCLDWAIT;
715 if ((sig == SIGKILL || sig == SIGSTOP) &&
716 act->sa_handler != SIG_DFL) {
717 mtx_unlock(&ps->ps_mtx);
723 * Change setting atomically.
726 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
727 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
728 if (sigact_flag_test(act, SA_SIGINFO)) {
729 ps->ps_sigact[_SIG_IDX(sig)] =
730 (__sighandler_t *)act->sa_sigaction;
731 SIGADDSET(ps->ps_siginfo, sig);
733 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
734 SIGDELSET(ps->ps_siginfo, sig);
736 if (!sigact_flag_test(act, SA_RESTART))
737 SIGADDSET(ps->ps_sigintr, sig);
739 SIGDELSET(ps->ps_sigintr, sig);
740 if (sigact_flag_test(act, SA_ONSTACK))
741 SIGADDSET(ps->ps_sigonstack, sig);
743 SIGDELSET(ps->ps_sigonstack, sig);
744 if (sigact_flag_test(act, SA_RESETHAND))
745 SIGADDSET(ps->ps_sigreset, sig);
747 SIGDELSET(ps->ps_sigreset, sig);
748 if (sigact_flag_test(act, SA_NODEFER))
749 SIGADDSET(ps->ps_signodefer, sig);
751 SIGDELSET(ps->ps_signodefer, sig);
752 if (sig == SIGCHLD) {
753 if (act->sa_flags & SA_NOCLDSTOP)
754 ps->ps_flag |= PS_NOCLDSTOP;
756 ps->ps_flag &= ~PS_NOCLDSTOP;
757 if (act->sa_flags & SA_NOCLDWAIT) {
759 * Paranoia: since SA_NOCLDWAIT is implemented
760 * by reparenting the dying child to PID 1 (and
761 * trust it to reap the zombie), PID 1 itself
762 * is forbidden to set SA_NOCLDWAIT.
765 ps->ps_flag &= ~PS_NOCLDWAIT;
767 ps->ps_flag |= PS_NOCLDWAIT;
769 ps->ps_flag &= ~PS_NOCLDWAIT;
770 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
771 ps->ps_flag |= PS_CLDSIGIGN;
773 ps->ps_flag &= ~PS_CLDSIGIGN;
776 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
777 * and for signals set to SIG_DFL where the default is to
778 * ignore. However, don't put SIGCONT in ps_sigignore, as we
779 * have to restart the process.
781 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
782 (sigprop(sig) & SIGPROP_IGNORE &&
783 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
784 /* never to be seen again */
785 sigqueue_delete_proc(p, sig);
787 /* easier in psignal */
788 SIGADDSET(ps->ps_sigignore, sig);
789 SIGDELSET(ps->ps_sigcatch, sig);
791 SIGDELSET(ps->ps_sigignore, sig);
792 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
793 SIGDELSET(ps->ps_sigcatch, sig);
795 SIGADDSET(ps->ps_sigcatch, sig);
797 #ifdef COMPAT_FREEBSD4
798 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
799 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
800 (flags & KSA_FREEBSD4) == 0)
801 SIGDELSET(ps->ps_freebsd4, sig);
803 SIGADDSET(ps->ps_freebsd4, sig);
806 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
807 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
808 (flags & KSA_OSIGSET) == 0)
809 SIGDELSET(ps->ps_osigset, sig);
811 SIGADDSET(ps->ps_osigset, sig);
814 mtx_unlock(&ps->ps_mtx);
819 #ifndef _SYS_SYSPROTO_H_
820 struct sigaction_args {
822 struct sigaction *act;
823 struct sigaction *oact;
827 sys_sigaction(struct thread *td, struct sigaction_args *uap)
829 struct sigaction act, oact;
830 struct sigaction *actp, *oactp;
833 actp = (uap->act != NULL) ? &act : NULL;
834 oactp = (uap->oact != NULL) ? &oact : NULL;
836 error = copyin(uap->act, actp, sizeof(act));
840 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
842 error = copyout(oactp, uap->oact, sizeof(oact));
846 #ifdef COMPAT_FREEBSD4
847 #ifndef _SYS_SYSPROTO_H_
848 struct freebsd4_sigaction_args {
850 struct sigaction *act;
851 struct sigaction *oact;
855 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
857 struct sigaction act, oact;
858 struct sigaction *actp, *oactp;
862 actp = (uap->act != NULL) ? &act : NULL;
863 oactp = (uap->oact != NULL) ? &oact : NULL;
865 error = copyin(uap->act, actp, sizeof(act));
869 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
871 error = copyout(oactp, uap->oact, sizeof(oact));
874 #endif /* COMAPT_FREEBSD4 */
876 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
877 #ifndef _SYS_SYSPROTO_H_
878 struct osigaction_args {
880 struct osigaction *nsa;
881 struct osigaction *osa;
885 osigaction(struct thread *td, struct osigaction_args *uap)
887 struct osigaction sa;
888 struct sigaction nsa, osa;
889 struct sigaction *nsap, *osap;
892 if (uap->signum <= 0 || uap->signum >= ONSIG)
895 nsap = (uap->nsa != NULL) ? &nsa : NULL;
896 osap = (uap->osa != NULL) ? &osa : NULL;
899 error = copyin(uap->nsa, &sa, sizeof(sa));
902 nsap->sa_handler = sa.sa_handler;
903 nsap->sa_flags = sa.sa_flags;
904 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
906 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
907 if (osap && !error) {
908 sa.sa_handler = osap->sa_handler;
909 sa.sa_flags = osap->sa_flags;
910 SIG2OSIG(osap->sa_mask, sa.sa_mask);
911 error = copyout(&sa, uap->osa, sizeof(sa));
916 #if !defined(__i386__)
917 /* Avoid replicating the same stub everywhere */
919 osigreturn(struct thread *td, struct osigreturn_args *uap)
922 return (nosys(td, (struct nosys_args *)uap));
925 #endif /* COMPAT_43 */
928 * Initialize signal state for process 0;
929 * set to ignore signals that are ignored by default.
932 siginit(struct proc *p)
939 mtx_lock(&ps->ps_mtx);
940 for (i = 1; i <= NSIG; i++) {
941 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
942 SIGADDSET(ps->ps_sigignore, i);
945 mtx_unlock(&ps->ps_mtx);
950 * Reset specified signal to the default disposition.
953 sigdflt(struct sigacts *ps, int sig)
956 mtx_assert(&ps->ps_mtx, MA_OWNED);
957 SIGDELSET(ps->ps_sigcatch, sig);
958 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
959 SIGADDSET(ps->ps_sigignore, sig);
960 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
961 SIGDELSET(ps->ps_siginfo, sig);
965 * Reset signals for an exec of the specified process.
968 execsigs(struct proc *p)
976 * Reset caught signals. Held signals remain held
977 * through td_sigmask (unless they were caught,
978 * and are now ignored by default).
980 PROC_LOCK_ASSERT(p, MA_OWNED);
982 mtx_lock(&ps->ps_mtx);
983 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
984 sig = sig_ffs(&ps->ps_sigcatch);
986 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
987 sigqueue_delete_proc(p, sig);
991 * As CloudABI processes cannot modify signal handlers, fully
992 * reset all signals to their default behavior. Do ignore
993 * SIGPIPE, as it would otherwise be impossible to recover from
994 * writes to broken pipes and sockets.
996 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
997 osigignore = ps->ps_sigignore;
998 while (SIGNOTEMPTY(osigignore)) {
999 sig = sig_ffs(&osigignore);
1000 SIGDELSET(osigignore, sig);
1004 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1008 * Reset stack state to the user stack.
1009 * Clear set of signals caught on the signal stack.
1012 MPASS(td->td_proc == p);
1013 td->td_sigstk.ss_flags = SS_DISABLE;
1014 td->td_sigstk.ss_size = 0;
1015 td->td_sigstk.ss_sp = 0;
1016 td->td_pflags &= ~TDP_ALTSTACK;
1018 * Reset no zombies if child dies flag as Solaris does.
1020 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1021 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1022 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1023 mtx_unlock(&ps->ps_mtx);
1027 * kern_sigprocmask()
1029 * Manipulate signal mask.
1032 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1035 sigset_t new_block, oset1;
1040 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1041 PROC_LOCK_ASSERT(p, MA_OWNED);
1044 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1045 ? MA_OWNED : MA_NOTOWNED);
1047 *oset = td->td_sigmask;
1054 oset1 = td->td_sigmask;
1055 SIGSETOR(td->td_sigmask, *set);
1056 new_block = td->td_sigmask;
1057 SIGSETNAND(new_block, oset1);
1060 SIGSETNAND(td->td_sigmask, *set);
1065 oset1 = td->td_sigmask;
1066 if (flags & SIGPROCMASK_OLD)
1067 SIGSETLO(td->td_sigmask, *set);
1069 td->td_sigmask = *set;
1070 new_block = td->td_sigmask;
1071 SIGSETNAND(new_block, oset1);
1080 * The new_block set contains signals that were not previously
1081 * blocked, but are blocked now.
1083 * In case we block any signal that was not previously blocked
1084 * for td, and process has the signal pending, try to schedule
1085 * signal delivery to some thread that does not block the
1086 * signal, possibly waking it up.
1088 if (p->p_numthreads != 1)
1089 reschedule_signals(p, new_block, flags);
1093 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1098 #ifndef _SYS_SYSPROTO_H_
1099 struct sigprocmask_args {
1101 const sigset_t *set;
1106 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1109 sigset_t *setp, *osetp;
1112 setp = (uap->set != NULL) ? &set : NULL;
1113 osetp = (uap->oset != NULL) ? &oset : NULL;
1115 error = copyin(uap->set, setp, sizeof(set));
1119 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1120 if (osetp && !error) {
1121 error = copyout(osetp, uap->oset, sizeof(oset));
1126 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1127 #ifndef _SYS_SYSPROTO_H_
1128 struct osigprocmask_args {
1134 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1139 OSIG2SIG(uap->mask, set);
1140 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1141 SIG2OSIG(oset, td->td_retval[0]);
1144 #endif /* COMPAT_43 */
1147 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1153 error = copyin(uap->set, &set, sizeof(set));
1155 td->td_retval[0] = error;
1159 error = kern_sigtimedwait(td, set, &ksi, NULL);
1161 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1163 if (error == ERESTART)
1165 td->td_retval[0] = error;
1169 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1170 td->td_retval[0] = error;
1175 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1178 struct timespec *timeout;
1184 error = copyin(uap->timeout, &ts, sizeof(ts));
1192 error = copyin(uap->set, &set, sizeof(set));
1196 error = kern_sigtimedwait(td, set, &ksi, timeout);
1201 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1204 td->td_retval[0] = ksi.ksi_signo;
1209 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1215 error = copyin(uap->set, &set, sizeof(set));
1219 error = kern_sigtimedwait(td, set, &ksi, NULL);
1224 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1227 td->td_retval[0] = ksi.ksi_signo;
1232 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1236 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1240 thr->td_si.si_signo = 0;
1245 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1246 struct timespec *timeout)
1249 sigset_t saved_mask, new_block;
1251 int error, sig, timo, timevalid = 0;
1252 struct timespec rts, ets, ts;
1260 if (timeout != NULL) {
1261 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1263 getnanouptime(&rts);
1265 timespecadd(&ets, timeout);
1269 /* Some signals can not be waited for. */
1270 SIG_CANTMASK(waitset);
1273 saved_mask = td->td_sigmask;
1274 SIGSETNAND(td->td_sigmask, waitset);
1276 mtx_lock(&ps->ps_mtx);
1278 mtx_unlock(&ps->ps_mtx);
1279 KASSERT(sig >= 0, ("sig %d", sig));
1280 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1281 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1282 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1292 * POSIX says this must be checked after looking for pending
1295 if (timeout != NULL) {
1300 getnanouptime(&rts);
1301 if (timespeccmp(&rts, &ets, >=)) {
1306 timespecsub(&ts, &rts);
1307 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1313 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1315 if (timeout != NULL) {
1316 if (error == ERESTART) {
1317 /* Timeout can not be restarted. */
1319 } else if (error == EAGAIN) {
1320 /* We will calculate timeout by ourself. */
1326 new_block = saved_mask;
1327 SIGSETNAND(new_block, td->td_sigmask);
1328 td->td_sigmask = saved_mask;
1330 * Fewer signals can be delivered to us, reschedule signal
1333 if (p->p_numthreads != 1)
1334 reschedule_signals(p, new_block, 0);
1337 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1339 if (ksi->ksi_code == SI_TIMER)
1340 itimer_accept(p, ksi->ksi_timerid, ksi);
1343 if (KTRPOINT(td, KTR_PSIG)) {
1346 mtx_lock(&ps->ps_mtx);
1347 action = ps->ps_sigact[_SIG_IDX(sig)];
1348 mtx_unlock(&ps->ps_mtx);
1349 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1352 if (sig == SIGKILL) {
1353 proc_td_siginfo_capture(td, &ksi->ksi_info);
1361 #ifndef _SYS_SYSPROTO_H_
1362 struct sigpending_args {
1367 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1369 struct proc *p = td->td_proc;
1373 pending = p->p_sigqueue.sq_signals;
1374 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1376 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1379 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1380 #ifndef _SYS_SYSPROTO_H_
1381 struct osigpending_args {
1386 osigpending(struct thread *td, struct osigpending_args *uap)
1388 struct proc *p = td->td_proc;
1392 pending = p->p_sigqueue.sq_signals;
1393 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1395 SIG2OSIG(pending, td->td_retval[0]);
1398 #endif /* COMPAT_43 */
1400 #if defined(COMPAT_43)
1402 * Generalized interface signal handler, 4.3-compatible.
1404 #ifndef _SYS_SYSPROTO_H_
1405 struct osigvec_args {
1413 osigvec(struct thread *td, struct osigvec_args *uap)
1416 struct sigaction nsa, osa;
1417 struct sigaction *nsap, *osap;
1420 if (uap->signum <= 0 || uap->signum >= ONSIG)
1422 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1423 osap = (uap->osv != NULL) ? &osa : NULL;
1425 error = copyin(uap->nsv, &vec, sizeof(vec));
1428 nsap->sa_handler = vec.sv_handler;
1429 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1430 nsap->sa_flags = vec.sv_flags;
1431 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1433 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1434 if (osap && !error) {
1435 vec.sv_handler = osap->sa_handler;
1436 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1437 vec.sv_flags = osap->sa_flags;
1438 vec.sv_flags &= ~SA_NOCLDWAIT;
1439 vec.sv_flags ^= SA_RESTART;
1440 error = copyout(&vec, uap->osv, sizeof(vec));
1445 #ifndef _SYS_SYSPROTO_H_
1446 struct osigblock_args {
1451 osigblock(struct thread *td, struct osigblock_args *uap)
1455 OSIG2SIG(uap->mask, set);
1456 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1457 SIG2OSIG(oset, td->td_retval[0]);
1461 #ifndef _SYS_SYSPROTO_H_
1462 struct osigsetmask_args {
1467 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1471 OSIG2SIG(uap->mask, set);
1472 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1473 SIG2OSIG(oset, td->td_retval[0]);
1476 #endif /* COMPAT_43 */
1479 * Suspend calling thread until signal, providing mask to be set in the
1482 #ifndef _SYS_SYSPROTO_H_
1483 struct sigsuspend_args {
1484 const sigset_t *sigmask;
1489 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1494 error = copyin(uap->sigmask, &mask, sizeof(mask));
1497 return (kern_sigsuspend(td, mask));
1501 kern_sigsuspend(struct thread *td, sigset_t mask)
1503 struct proc *p = td->td_proc;
1507 * When returning from sigsuspend, we want
1508 * the old mask to be restored after the
1509 * signal handler has finished. Thus, we
1510 * save it here and mark the sigacts structure
1514 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1515 SIGPROCMASK_PROC_LOCKED);
1516 td->td_pflags |= TDP_OLDMASK;
1519 * Process signals now. Otherwise, we can get spurious wakeup
1520 * due to signal entered process queue, but delivered to other
1521 * thread. But sigsuspend should return only on signal
1524 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1525 for (has_sig = 0; !has_sig;) {
1526 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1529 thread_suspend_check(0);
1530 mtx_lock(&p->p_sigacts->ps_mtx);
1531 while ((sig = cursig(td)) != 0) {
1532 KASSERT(sig >= 0, ("sig %d", sig));
1533 has_sig += postsig(sig);
1535 mtx_unlock(&p->p_sigacts->ps_mtx);
1538 td->td_errno = EINTR;
1539 td->td_pflags |= TDP_NERRNO;
1540 return (EJUSTRETURN);
1543 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1545 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1546 * convention: libc stub passes mask, not pointer, to save a copyin.
1548 #ifndef _SYS_SYSPROTO_H_
1549 struct osigsuspend_args {
1555 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1559 OSIG2SIG(uap->mask, mask);
1560 return (kern_sigsuspend(td, mask));
1562 #endif /* COMPAT_43 */
1564 #if defined(COMPAT_43)
1565 #ifndef _SYS_SYSPROTO_H_
1566 struct osigstack_args {
1567 struct sigstack *nss;
1568 struct sigstack *oss;
1573 osigstack(struct thread *td, struct osigstack_args *uap)
1575 struct sigstack nss, oss;
1578 if (uap->nss != NULL) {
1579 error = copyin(uap->nss, &nss, sizeof(nss));
1583 oss.ss_sp = td->td_sigstk.ss_sp;
1584 oss.ss_onstack = sigonstack(cpu_getstack(td));
1585 if (uap->nss != NULL) {
1586 td->td_sigstk.ss_sp = nss.ss_sp;
1587 td->td_sigstk.ss_size = 0;
1588 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1589 td->td_pflags |= TDP_ALTSTACK;
1591 if (uap->oss != NULL)
1592 error = copyout(&oss, uap->oss, sizeof(oss));
1596 #endif /* COMPAT_43 */
1598 #ifndef _SYS_SYSPROTO_H_
1599 struct sigaltstack_args {
1606 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1611 if (uap->ss != NULL) {
1612 error = copyin(uap->ss, &ss, sizeof(ss));
1616 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1617 (uap->oss != NULL) ? &oss : NULL);
1620 if (uap->oss != NULL)
1621 error = copyout(&oss, uap->oss, sizeof(stack_t));
1626 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1628 struct proc *p = td->td_proc;
1631 oonstack = sigonstack(cpu_getstack(td));
1634 *oss = td->td_sigstk;
1635 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1636 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1642 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1644 if (!(ss->ss_flags & SS_DISABLE)) {
1645 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1648 td->td_sigstk = *ss;
1649 td->td_pflags |= TDP_ALTSTACK;
1651 td->td_pflags &= ~TDP_ALTSTACK;
1658 * Common code for kill process group/broadcast kill.
1659 * cp is calling process.
1662 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1674 sx_slock(&allproc_lock);
1675 FOREACH_PROC_IN_SYSTEM(p) {
1676 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1677 p == td->td_proc || p->p_state == PRS_NEW) {
1681 err = p_cansignal(td, p, sig);
1684 pksignal(p, sig, ksi);
1687 else if (ret == ESRCH)
1691 sx_sunlock(&allproc_lock);
1693 sx_slock(&proctree_lock);
1696 * zero pgid means send to my process group.
1698 pgrp = td->td_proc->p_pgrp;
1701 pgrp = pgfind(pgid);
1703 sx_sunlock(&proctree_lock);
1707 sx_sunlock(&proctree_lock);
1708 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1710 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1711 p->p_state == PRS_NEW) {
1715 err = p_cansignal(td, p, sig);
1718 pksignal(p, sig, ksi);
1721 else if (ret == ESRCH)
1730 #ifndef _SYS_SYSPROTO_H_
1738 sys_kill(struct thread *td, struct kill_args *uap)
1745 * A process in capability mode can send signals only to himself.
1746 * The main rationale behind this is that abort(3) is implemented as
1747 * kill(getpid(), SIGABRT).
1749 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1752 AUDIT_ARG_SIGNUM(uap->signum);
1753 AUDIT_ARG_PID(uap->pid);
1754 if ((u_int)uap->signum > _SIG_MAXSIG)
1757 ksiginfo_init(&ksi);
1758 ksi.ksi_signo = uap->signum;
1759 ksi.ksi_code = SI_USER;
1760 ksi.ksi_pid = td->td_proc->p_pid;
1761 ksi.ksi_uid = td->td_ucred->cr_ruid;
1764 /* kill single process */
1765 if ((p = pfind_any(uap->pid)) == NULL)
1767 AUDIT_ARG_PROCESS(p);
1768 error = p_cansignal(td, p, uap->signum);
1769 if (error == 0 && uap->signum)
1770 pksignal(p, uap->signum, &ksi);
1775 case -1: /* broadcast signal */
1776 return (killpg1(td, uap->signum, 0, 1, &ksi));
1777 case 0: /* signal own process group */
1778 return (killpg1(td, uap->signum, 0, 0, &ksi));
1779 default: /* negative explicit process group */
1780 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1786 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1791 AUDIT_ARG_SIGNUM(uap->signum);
1792 AUDIT_ARG_FD(uap->fd);
1793 if ((u_int)uap->signum > _SIG_MAXSIG)
1796 error = procdesc_find(td, uap->fd, &cap_pdkill_rights, &p);
1799 AUDIT_ARG_PROCESS(p);
1800 error = p_cansignal(td, p, uap->signum);
1801 if (error == 0 && uap->signum)
1802 kern_psignal(p, uap->signum);
1807 #if defined(COMPAT_43)
1808 #ifndef _SYS_SYSPROTO_H_
1809 struct okillpg_args {
1816 okillpg(struct thread *td, struct okillpg_args *uap)
1820 AUDIT_ARG_SIGNUM(uap->signum);
1821 AUDIT_ARG_PID(uap->pgid);
1822 if ((u_int)uap->signum > _SIG_MAXSIG)
1825 ksiginfo_init(&ksi);
1826 ksi.ksi_signo = uap->signum;
1827 ksi.ksi_code = SI_USER;
1828 ksi.ksi_pid = td->td_proc->p_pid;
1829 ksi.ksi_uid = td->td_ucred->cr_ruid;
1830 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1832 #endif /* COMPAT_43 */
1834 #ifndef _SYS_SYSPROTO_H_
1835 struct sigqueue_args {
1838 /* union sigval */ void *value;
1842 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1846 sv.sival_ptr = uap->value;
1848 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1852 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1858 if ((u_int)signum > _SIG_MAXSIG)
1862 * Specification says sigqueue can only send signal to
1868 if ((p = pfind_any(pid)) == NULL)
1870 error = p_cansignal(td, p, signum);
1871 if (error == 0 && signum != 0) {
1872 ksiginfo_init(&ksi);
1873 ksi.ksi_flags = KSI_SIGQ;
1874 ksi.ksi_signo = signum;
1875 ksi.ksi_code = SI_QUEUE;
1876 ksi.ksi_pid = td->td_proc->p_pid;
1877 ksi.ksi_uid = td->td_ucred->cr_ruid;
1878 ksi.ksi_value = *value;
1879 error = pksignal(p, ksi.ksi_signo, &ksi);
1886 * Send a signal to a process group.
1889 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1894 sx_slock(&proctree_lock);
1895 pgrp = pgfind(pgid);
1896 sx_sunlock(&proctree_lock);
1898 pgsignal(pgrp, sig, 0, ksi);
1905 * Send a signal to a process group. If checktty is 1,
1906 * limit to members which have a controlling terminal.
1909 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1914 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1915 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1917 if (p->p_state == PRS_NORMAL &&
1918 (checkctty == 0 || p->p_flag & P_CONTROLT))
1919 pksignal(p, sig, ksi);
1927 * Recalculate the signal mask and reset the signal disposition after
1928 * usermode frame for delivery is formed. Should be called after
1929 * mach-specific routine, because sysent->sv_sendsig() needs correct
1930 * ps_siginfo and signal mask.
1933 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1937 mtx_assert(&ps->ps_mtx, MA_OWNED);
1938 td->td_ru.ru_nsignals++;
1939 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1940 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1941 SIGADDSET(mask, sig);
1942 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1943 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1944 if (SIGISMEMBER(ps->ps_sigreset, sig))
1950 * Send a signal caused by a trap to the current thread. If it will be
1951 * caught immediately, deliver it with correct code. Otherwise, post it
1955 trapsignal(struct thread *td, ksiginfo_t *ksi)
1963 sig = ksi->ksi_signo;
1964 code = ksi->ksi_code;
1965 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1969 mtx_lock(&ps->ps_mtx);
1970 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1971 !SIGISMEMBER(td->td_sigmask, sig)) {
1973 if (KTRPOINT(curthread, KTR_PSIG))
1974 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1975 &td->td_sigmask, code);
1977 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1978 ksi, &td->td_sigmask);
1979 postsig_done(sig, td, ps);
1980 mtx_unlock(&ps->ps_mtx);
1983 * Avoid a possible infinite loop if the thread
1984 * masking the signal or process is ignoring the
1987 if (kern_forcesigexit &&
1988 (SIGISMEMBER(td->td_sigmask, sig) ||
1989 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1990 SIGDELSET(td->td_sigmask, sig);
1991 SIGDELSET(ps->ps_sigcatch, sig);
1992 SIGDELSET(ps->ps_sigignore, sig);
1993 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1995 mtx_unlock(&ps->ps_mtx);
1996 p->p_code = code; /* XXX for core dump/debugger */
1997 p->p_sig = sig; /* XXX to verify code */
1998 tdsendsignal(p, td, sig, ksi);
2003 static struct thread *
2004 sigtd(struct proc *p, int sig, int prop)
2006 struct thread *td, *signal_td;
2008 PROC_LOCK_ASSERT(p, MA_OWNED);
2011 * Check if current thread can handle the signal without
2012 * switching context to another thread.
2014 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
2017 FOREACH_THREAD_IN_PROC(p, td) {
2018 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2023 if (signal_td == NULL)
2024 signal_td = FIRST_THREAD_IN_PROC(p);
2029 * Send the signal to the process. If the signal has an action, the action
2030 * is usually performed by the target process rather than the caller; we add
2031 * the signal to the set of pending signals for the process.
2034 * o When a stop signal is sent to a sleeping process that takes the
2035 * default action, the process is stopped without awakening it.
2036 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2037 * regardless of the signal action (eg, blocked or ignored).
2039 * Other ignored signals are discarded immediately.
2041 * NB: This function may be entered from the debugger via the "kill" DDB
2042 * command. There is little that can be done to mitigate the possibly messy
2043 * side effects of this unwise possibility.
2046 kern_psignal(struct proc *p, int sig)
2050 ksiginfo_init(&ksi);
2051 ksi.ksi_signo = sig;
2052 ksi.ksi_code = SI_KERNEL;
2053 (void) tdsendsignal(p, NULL, sig, &ksi);
2057 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2060 return (tdsendsignal(p, NULL, sig, ksi));
2063 /* Utility function for finding a thread to send signal event to. */
2065 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2069 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2070 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2082 tdsignal(struct thread *td, int sig)
2086 ksiginfo_init(&ksi);
2087 ksi.ksi_signo = sig;
2088 ksi.ksi_code = SI_KERNEL;
2089 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2093 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2096 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2100 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2103 sigqueue_t *sigqueue;
2110 MPASS(td == NULL || p == td->td_proc);
2111 PROC_LOCK_ASSERT(p, MA_OWNED);
2113 if (!_SIG_VALID(sig))
2114 panic("%s(): invalid signal %d", __func__, sig);
2116 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2119 * IEEE Std 1003.1-2001: return success when killing a zombie.
2121 if (p->p_state == PRS_ZOMBIE) {
2122 if (ksi && (ksi->ksi_flags & KSI_INS))
2123 ksiginfo_tryfree(ksi);
2128 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2129 prop = sigprop(sig);
2132 td = sigtd(p, sig, prop);
2133 sigqueue = &p->p_sigqueue;
2135 sigqueue = &td->td_sigqueue;
2137 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2140 * If the signal is being ignored,
2141 * then we forget about it immediately.
2142 * (Note: we don't set SIGCONT in ps_sigignore,
2143 * and if it is set to SIG_IGN,
2144 * action will be SIG_DFL here.)
2146 mtx_lock(&ps->ps_mtx);
2147 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2148 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2150 mtx_unlock(&ps->ps_mtx);
2151 if (ksi && (ksi->ksi_flags & KSI_INS))
2152 ksiginfo_tryfree(ksi);
2155 if (SIGISMEMBER(td->td_sigmask, sig))
2157 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2161 if (SIGISMEMBER(ps->ps_sigintr, sig))
2165 mtx_unlock(&ps->ps_mtx);
2167 if (prop & SIGPROP_CONT)
2168 sigqueue_delete_stopmask_proc(p);
2169 else if (prop & SIGPROP_STOP) {
2171 * If sending a tty stop signal to a member of an orphaned
2172 * process group, discard the signal here if the action
2173 * is default; don't stop the process below if sleeping,
2174 * and don't clear any pending SIGCONT.
2176 if ((prop & SIGPROP_TTYSTOP) &&
2177 (p->p_pgrp->pg_jobc == 0) &&
2178 (action == SIG_DFL)) {
2179 if (ksi && (ksi->ksi_flags & KSI_INS))
2180 ksiginfo_tryfree(ksi);
2183 sigqueue_delete_proc(p, SIGCONT);
2184 if (p->p_flag & P_CONTINUED) {
2185 p->p_flag &= ~P_CONTINUED;
2186 PROC_LOCK(p->p_pptr);
2187 sigqueue_take(p->p_ksi);
2188 PROC_UNLOCK(p->p_pptr);
2192 ret = sigqueue_add(sigqueue, sig, ksi);
2197 * Defer further processing for signals which are held,
2198 * except that stopped processes must be continued by SIGCONT.
2200 if (action == SIG_HOLD &&
2201 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2204 /* SIGKILL: Remove procfs STOPEVENTs. */
2205 if (sig == SIGKILL) {
2206 /* from procfs_ioctl.c: PIOCBIC */
2208 /* from procfs_ioctl.c: PIOCCONT */
2213 * Some signals have a process-wide effect and a per-thread
2214 * component. Most processing occurs when the process next
2215 * tries to cross the user boundary, however there are some
2216 * times when processing needs to be done immediately, such as
2217 * waking up threads so that they can cross the user boundary.
2218 * We try to do the per-process part here.
2220 if (P_SHOULDSTOP(p)) {
2221 KASSERT(!(p->p_flag & P_WEXIT),
2222 ("signal to stopped but exiting process"));
2223 if (sig == SIGKILL) {
2225 * If traced process is already stopped,
2226 * then no further action is necessary.
2228 if (p->p_flag & P_TRACED)
2231 * SIGKILL sets process running.
2232 * It will die elsewhere.
2233 * All threads must be restarted.
2235 p->p_flag &= ~P_STOPPED_SIG;
2239 if (prop & SIGPROP_CONT) {
2241 * If traced process is already stopped,
2242 * then no further action is necessary.
2244 if (p->p_flag & P_TRACED)
2247 * If SIGCONT is default (or ignored), we continue the
2248 * process but don't leave the signal in sigqueue as
2249 * it has no further action. If SIGCONT is held, we
2250 * continue the process and leave the signal in
2251 * sigqueue. If the process catches SIGCONT, let it
2252 * handle the signal itself. If it isn't waiting on
2253 * an event, it goes back to run state.
2254 * Otherwise, process goes back to sleep state.
2256 p->p_flag &= ~P_STOPPED_SIG;
2258 if (p->p_numthreads == p->p_suspcount) {
2260 p->p_flag |= P_CONTINUED;
2261 p->p_xsig = SIGCONT;
2262 PROC_LOCK(p->p_pptr);
2263 childproc_continued(p);
2264 PROC_UNLOCK(p->p_pptr);
2267 if (action == SIG_DFL) {
2268 thread_unsuspend(p);
2270 sigqueue_delete(sigqueue, sig);
2273 if (action == SIG_CATCH) {
2275 * The process wants to catch it so it needs
2276 * to run at least one thread, but which one?
2282 * The signal is not ignored or caught.
2284 thread_unsuspend(p);
2289 if (prop & SIGPROP_STOP) {
2291 * If traced process is already stopped,
2292 * then no further action is necessary.
2294 if (p->p_flag & P_TRACED)
2297 * Already stopped, don't need to stop again
2298 * (If we did the shell could get confused).
2299 * Just make sure the signal STOP bit set.
2301 p->p_flag |= P_STOPPED_SIG;
2302 sigqueue_delete(sigqueue, sig);
2307 * All other kinds of signals:
2308 * If a thread is sleeping interruptibly, simulate a
2309 * wakeup so that when it is continued it will be made
2310 * runnable and can look at the signal. However, don't make
2311 * the PROCESS runnable, leave it stopped.
2312 * It may run a bit until it hits a thread_suspend_check().
2317 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2318 wakeup_swapper = sleepq_abort(td, intrval);
2325 * Mutexes are short lived. Threads waiting on them will
2326 * hit thread_suspend_check() soon.
2328 } else if (p->p_state == PRS_NORMAL) {
2329 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2330 tdsigwakeup(td, sig, action, intrval);
2334 MPASS(action == SIG_DFL);
2336 if (prop & SIGPROP_STOP) {
2337 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2339 p->p_flag |= P_STOPPED_SIG;
2342 wakeup_swapper = sig_suspend_threads(td, p, 1);
2343 if (p->p_numthreads == p->p_suspcount) {
2345 * only thread sending signal to another
2346 * process can reach here, if thread is sending
2347 * signal to its process, because thread does
2348 * not suspend itself here, p_numthreads
2349 * should never be equal to p_suspcount.
2353 sigqueue_delete_proc(p, p->p_xsig);
2361 /* Not in "NORMAL" state. discard the signal. */
2362 sigqueue_delete(sigqueue, sig);
2367 * The process is not stopped so we need to apply the signal to all the
2371 tdsigwakeup(td, sig, action, intrval);
2373 thread_unsuspend(p);
2376 /* If we jump here, proc slock should not be owned. */
2377 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2382 * The force of a signal has been directed against a single
2383 * thread. We need to see what we can do about knocking it
2384 * out of any sleep it may be in etc.
2387 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2389 struct proc *p = td->td_proc;
2394 PROC_LOCK_ASSERT(p, MA_OWNED);
2395 prop = sigprop(sig);
2400 * Bring the priority of a thread up if we want it to get
2401 * killed in this lifetime. Be careful to avoid bumping the
2402 * priority of the idle thread, since we still allow to signal
2405 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2406 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2407 sched_prio(td, PUSER);
2408 if (TD_ON_SLEEPQ(td)) {
2410 * If thread is sleeping uninterruptibly
2411 * we can't interrupt the sleep... the signal will
2412 * be noticed when the process returns through
2413 * trap() or syscall().
2415 if ((td->td_flags & TDF_SINTR) == 0)
2418 * If SIGCONT is default (or ignored) and process is
2419 * asleep, we are finished; the process should not
2422 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2425 sigqueue_delete(&p->p_sigqueue, sig);
2427 * It may be on either list in this state.
2428 * Remove from both for now.
2430 sigqueue_delete(&td->td_sigqueue, sig);
2435 * Don't awaken a sleeping thread for SIGSTOP if the
2436 * STOP signal is deferred.
2438 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2439 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2443 * Give low priority threads a better chance to run.
2445 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2446 sched_prio(td, PUSER);
2448 wakeup_swapper = sleepq_abort(td, intrval);
2451 * Other states do nothing with the signal immediately,
2452 * other than kicking ourselves if we are running.
2453 * It will either never be noticed, or noticed very soon.
2456 if (TD_IS_RUNNING(td) && td != curthread)
2468 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2473 PROC_LOCK_ASSERT(p, MA_OWNED);
2474 PROC_SLOCK_ASSERT(p, MA_OWNED);
2475 MPASS(sending || td == curthread);
2478 FOREACH_THREAD_IN_PROC(p, td2) {
2480 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2481 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2482 (td2->td_flags & TDF_SINTR)) {
2483 if (td2->td_flags & TDF_SBDRY) {
2485 * Once a thread is asleep with
2486 * TDF_SBDRY and without TDF_SERESTART
2487 * or TDF_SEINTR set, it should never
2488 * become suspended due to this check.
2490 KASSERT(!TD_IS_SUSPENDED(td2),
2491 ("thread with deferred stops suspended"));
2492 if (TD_SBDRY_INTR(td2))
2493 wakeup_swapper |= sleepq_abort(td2,
2494 TD_SBDRY_ERRNO(td2));
2495 } else if (!TD_IS_SUSPENDED(td2)) {
2496 thread_suspend_one(td2);
2498 } else if (!TD_IS_SUSPENDED(td2)) {
2499 if (sending || td != td2)
2500 td2->td_flags |= TDF_ASTPENDING;
2502 if (TD_IS_RUNNING(td2) && td2 != td)
2503 forward_signal(td2);
2508 return (wakeup_swapper);
2512 * Stop the process for an event deemed interesting to the debugger. If si is
2513 * non-NULL, this is a signal exchange; the new signal requested by the
2514 * debugger will be returned for handling. If si is NULL, this is some other
2515 * type of interesting event. The debugger may request a signal be delivered in
2516 * that case as well, however it will be deferred until it can be handled.
2519 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2521 struct proc *p = td->td_proc;
2526 PROC_LOCK_ASSERT(p, MA_OWNED);
2527 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2528 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2529 &p->p_mtx.lock_object, "Stopping for traced signal");
2533 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2534 td->td_dbgflags |= TDB_XSIG;
2535 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2536 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2538 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2541 * Ensure that, if we've been PT_KILLed, the
2542 * exit status reflects that. Another thread
2543 * may also be in ptracestop(), having just
2544 * received the SIGKILL, but this thread was
2545 * unsuspended first.
2547 td->td_dbgflags &= ~TDB_XSIG;
2548 td->td_xsig = SIGKILL;
2552 if (p->p_flag & P_SINGLE_EXIT &&
2553 !(td->td_dbgflags & TDB_EXIT)) {
2555 * Ignore ptrace stops except for thread exit
2556 * events when the process exits.
2558 td->td_dbgflags &= ~TDB_XSIG;
2564 * Make wait(2) work. Ensure that right after the
2565 * attach, the thread which was decided to become the
2566 * leader of attach gets reported to the waiter.
2567 * Otherwise, just avoid overwriting another thread's
2568 * assignment to p_xthread. If another thread has
2569 * already set p_xthread, the current thread will get
2570 * a chance to report itself upon the next iteration.
2572 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2573 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2574 p->p_xthread == NULL)) {
2577 td->td_dbgflags &= ~TDB_FSTP;
2578 p->p_flag2 &= ~P2_PTRACE_FSTP;
2579 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2580 sig_suspend_threads(td, p, 0);
2582 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2583 td->td_dbgflags &= ~TDB_STOPATFORK;
2586 thread_suspend_switch(td, p);
2587 if (p->p_xthread == td)
2588 p->p_xthread = NULL;
2589 if (!(p->p_flag & P_TRACED))
2591 if (td->td_dbgflags & TDB_SUSPEND) {
2592 if (p->p_flag & P_SINGLE_EXIT)
2600 if (si != NULL && sig == td->td_xsig) {
2601 /* Parent wants us to take the original signal unchanged. */
2602 si->ksi_flags |= KSI_HEAD;
2603 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2605 } else if (td->td_xsig != 0) {
2607 * If parent wants us to take a new signal, then it will leave
2608 * it in td->td_xsig; otherwise we just look for signals again.
2610 ksiginfo_init(&ksi);
2611 ksi.ksi_signo = td->td_xsig;
2612 ksi.ksi_flags |= KSI_PTRACE;
2613 prop = sigprop(td->td_xsig);
2614 td2 = sigtd(p, td->td_xsig, prop);
2615 tdsendsignal(p, td2, td->td_xsig, &ksi);
2620 return (td->td_xsig);
2624 reschedule_signals(struct proc *p, sigset_t block, int flags)
2630 PROC_LOCK_ASSERT(p, MA_OWNED);
2632 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2633 MA_OWNED : MA_NOTOWNED);
2634 if (SIGISEMPTY(p->p_siglist))
2636 SIGSETAND(block, p->p_siglist);
2637 while ((sig = sig_ffs(&block)) != 0) {
2638 SIGDELSET(block, sig);
2639 td = sigtd(p, sig, 0);
2641 if (!(flags & SIGPROCMASK_PS_LOCKED))
2642 mtx_lock(&ps->ps_mtx);
2643 if (p->p_flag & P_TRACED ||
2644 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2645 !SIGISMEMBER(td->td_sigmask, sig)))
2646 tdsigwakeup(td, sig, SIG_CATCH,
2647 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2649 if (!(flags & SIGPROCMASK_PS_LOCKED))
2650 mtx_unlock(&ps->ps_mtx);
2655 tdsigcleanup(struct thread *td)
2661 PROC_LOCK_ASSERT(p, MA_OWNED);
2663 sigqueue_flush(&td->td_sigqueue);
2664 if (p->p_numthreads == 1)
2668 * Since we cannot handle signals, notify signal post code
2669 * about this by filling the sigmask.
2671 * Also, if needed, wake up thread(s) that do not block the
2672 * same signals as the exiting thread, since the thread might
2673 * have been selected for delivery and woken up.
2675 SIGFILLSET(unblocked);
2676 SIGSETNAND(unblocked, td->td_sigmask);
2677 SIGFILLSET(td->td_sigmask);
2678 reschedule_signals(p, unblocked, 0);
2683 sigdeferstop_curr_flags(int cflags)
2686 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2687 (cflags & TDF_SBDRY) != 0);
2688 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2692 * Defer the delivery of SIGSTOP for the current thread, according to
2693 * the requested mode. Returns previous flags, which must be restored
2694 * by sigallowstop().
2696 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2697 * cleared by the current thread, which allow the lock-less read-only
2701 sigdeferstop_impl(int mode)
2707 cflags = sigdeferstop_curr_flags(td->td_flags);
2709 case SIGDEFERSTOP_NOP:
2712 case SIGDEFERSTOP_OFF:
2715 case SIGDEFERSTOP_SILENT:
2716 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2718 case SIGDEFERSTOP_EINTR:
2719 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2721 case SIGDEFERSTOP_ERESTART:
2722 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2725 panic("sigdeferstop: invalid mode %x", mode);
2728 if (cflags == nflags)
2729 return (SIGDEFERSTOP_VAL_NCHG);
2731 td->td_flags = (td->td_flags & ~cflags) | nflags;
2737 * Restores the STOP handling mode, typically permitting the delivery
2738 * of SIGSTOP for the current thread. This does not immediately
2739 * suspend if a stop was posted. Instead, the thread will suspend
2740 * either via ast() or a subsequent interruptible sleep.
2743 sigallowstop_impl(int prev)
2748 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2749 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2750 ("sigallowstop: incorrect previous mode %x", prev));
2752 cflags = sigdeferstop_curr_flags(td->td_flags);
2753 if (cflags != prev) {
2755 td->td_flags = (td->td_flags & ~cflags) | prev;
2761 * If the current process has received a signal (should be caught or cause
2762 * termination, should interrupt current syscall), return the signal number.
2763 * Stop signals with default action are processed immediately, then cleared;
2764 * they aren't returned. This is checked after each entry to the system for
2765 * a syscall or trap (though this can usually be done without calling issignal
2766 * by checking the pending signal masks in cursig.) The normal call
2769 * while (sig = cursig(curthread))
2773 issignal(struct thread *td)
2777 struct sigqueue *queue;
2778 sigset_t sigpending;
2780 int prop, sig, traced;
2784 mtx_assert(&ps->ps_mtx, MA_OWNED);
2785 PROC_LOCK_ASSERT(p, MA_OWNED);
2787 traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2789 sigpending = td->td_sigqueue.sq_signals;
2790 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2791 SIGSETNAND(sigpending, td->td_sigmask);
2793 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
2794 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2795 SIG_STOPSIGMASK(sigpending);
2796 if (SIGISEMPTY(sigpending)) /* no signal to send */
2798 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2799 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2800 SIGISMEMBER(sigpending, SIGSTOP)) {
2802 * If debugger just attached, always consume
2803 * SIGSTOP from ptrace(PT_ATTACH) first, to
2804 * execute the debugger attach ritual in
2808 td->td_dbgflags |= TDB_FSTP;
2810 sig = sig_ffs(&sigpending);
2813 if (p->p_stops & S_SIG) {
2814 mtx_unlock(&ps->ps_mtx);
2815 stopevent(p, S_SIG, sig);
2816 mtx_lock(&ps->ps_mtx);
2820 * We should see pending but ignored signals
2821 * only if P_TRACED was on when they were posted.
2823 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2824 sigqueue_delete(&td->td_sigqueue, sig);
2825 sigqueue_delete(&p->p_sigqueue, sig);
2828 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2830 * If traced, always stop.
2831 * Remove old signal from queue before the stop.
2832 * XXX shrug off debugger, it causes siginfo to
2835 queue = &td->td_sigqueue;
2836 ksiginfo_init(&ksi);
2837 if (sigqueue_get(queue, sig, &ksi) == 0) {
2838 queue = &p->p_sigqueue;
2839 sigqueue_get(queue, sig, &ksi);
2841 td->td_si = ksi.ksi_info;
2843 mtx_unlock(&ps->ps_mtx);
2844 sig = ptracestop(td, sig, &ksi);
2845 mtx_lock(&ps->ps_mtx);
2848 * Keep looking if the debugger discarded or
2849 * replaced the signal.
2855 * If the signal became masked, re-queue it.
2857 if (SIGISMEMBER(td->td_sigmask, sig)) {
2858 ksi.ksi_flags |= KSI_HEAD;
2859 sigqueue_add(&p->p_sigqueue, sig, &ksi);
2864 * If the traced bit got turned off, requeue
2865 * the signal and go back up to the top to
2866 * rescan signals. This ensures that p_sig*
2867 * and p_sigact are consistent.
2869 if ((p->p_flag & P_TRACED) == 0) {
2870 ksi.ksi_flags |= KSI_HEAD;
2871 sigqueue_add(queue, sig, &ksi);
2876 prop = sigprop(sig);
2879 * Decide whether the signal should be returned.
2880 * Return the signal's number, or fall through
2881 * to clear it from the pending mask.
2883 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2885 case (intptr_t)SIG_DFL:
2887 * Don't take default actions on system processes.
2889 if (p->p_pid <= 1) {
2892 * Are you sure you want to ignore SIGSEGV
2895 printf("Process (pid %lu) got signal %d\n",
2896 (u_long)p->p_pid, sig);
2898 break; /* == ignore */
2901 * If there is a pending stop signal to process with
2902 * default action, stop here, then clear the signal.
2903 * Traced or exiting processes should ignore stops.
2904 * Additionally, a member of an orphaned process group
2905 * should ignore tty stops.
2907 if (prop & SIGPROP_STOP) {
2909 (P_TRACED | P_WEXIT | P_SINGLE_EXIT) ||
2910 (p->p_pgrp->pg_jobc == 0 &&
2911 prop & SIGPROP_TTYSTOP))
2912 break; /* == ignore */
2913 if (TD_SBDRY_INTR(td)) {
2914 KASSERT((td->td_flags & TDF_SBDRY) != 0,
2915 ("lost TDF_SBDRY"));
2918 mtx_unlock(&ps->ps_mtx);
2919 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2920 &p->p_mtx.lock_object, "Catching SIGSTOP");
2921 sigqueue_delete(&td->td_sigqueue, sig);
2922 sigqueue_delete(&p->p_sigqueue, sig);
2923 p->p_flag |= P_STOPPED_SIG;
2926 sig_suspend_threads(td, p, 0);
2927 thread_suspend_switch(td, p);
2929 mtx_lock(&ps->ps_mtx);
2931 } else if (prop & SIGPROP_IGNORE) {
2933 * Except for SIGCONT, shouldn't get here.
2934 * Default action is to ignore; drop it.
2936 break; /* == ignore */
2941 case (intptr_t)SIG_IGN:
2943 * Masking above should prevent us ever trying
2944 * to take action on an ignored signal other
2945 * than SIGCONT, unless process is traced.
2947 if ((prop & SIGPROP_CONT) == 0 &&
2948 (p->p_flag & P_TRACED) == 0)
2949 printf("issignal\n");
2950 break; /* == ignore */
2954 * This signal has an action, let
2955 * postsig() process it.
2959 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2960 sigqueue_delete(&p->p_sigqueue, sig);
2967 thread_stopped(struct proc *p)
2971 PROC_LOCK_ASSERT(p, MA_OWNED);
2972 PROC_SLOCK_ASSERT(p, MA_OWNED);
2976 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2978 p->p_flag &= ~P_WAITED;
2979 PROC_LOCK(p->p_pptr);
2980 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2981 CLD_TRAPPED : CLD_STOPPED);
2982 PROC_UNLOCK(p->p_pptr);
2988 * Take the action for the specified signal
2989 * from the current set of pending signals.
2999 sigset_t returnmask;
3001 KASSERT(sig != 0, ("postsig"));
3005 PROC_LOCK_ASSERT(p, MA_OWNED);
3007 mtx_assert(&ps->ps_mtx, MA_OWNED);
3008 ksiginfo_init(&ksi);
3009 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3010 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3012 ksi.ksi_signo = sig;
3013 if (ksi.ksi_code == SI_TIMER)
3014 itimer_accept(p, ksi.ksi_timerid, &ksi);
3015 action = ps->ps_sigact[_SIG_IDX(sig)];
3017 if (KTRPOINT(td, KTR_PSIG))
3018 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3019 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3021 if ((p->p_stops & S_SIG) != 0) {
3022 mtx_unlock(&ps->ps_mtx);
3023 stopevent(p, S_SIG, sig);
3024 mtx_lock(&ps->ps_mtx);
3027 if (action == SIG_DFL) {
3029 * Default action, where the default is to kill
3030 * the process. (Other cases were ignored above.)
3032 mtx_unlock(&ps->ps_mtx);
3033 proc_td_siginfo_capture(td, &ksi.ksi_info);
3038 * If we get here, the signal must be caught.
3040 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3041 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3042 ("postsig action: blocked sig %d", sig));
3045 * Set the new mask value and also defer further
3046 * occurrences of this signal.
3048 * Special case: user has done a sigsuspend. Here the
3049 * current mask is not of interest, but rather the
3050 * mask from before the sigsuspend is what we want
3051 * restored after the signal processing is completed.
3053 if (td->td_pflags & TDP_OLDMASK) {
3054 returnmask = td->td_oldsigmask;
3055 td->td_pflags &= ~TDP_OLDMASK;
3057 returnmask = td->td_sigmask;
3059 if (p->p_sig == sig) {
3063 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3064 postsig_done(sig, td, ps);
3070 * Kill the current process for stated reason.
3073 killproc(struct proc *p, char *why)
3076 PROC_LOCK_ASSERT(p, MA_OWNED);
3077 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3079 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
3080 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
3081 p->p_flag |= P_WKILLED;
3082 kern_psignal(p, SIGKILL);
3086 * Force the current process to exit with the specified signal, dumping core
3087 * if appropriate. We bypass the normal tests for masked and caught signals,
3088 * allowing unrecoverable failures to terminate the process without changing
3089 * signal state. Mark the accounting record with the signal termination.
3090 * If dumping core, save the signal number for the debugger. Calls exit and
3094 sigexit(struct thread *td, int sig)
3096 struct proc *p = td->td_proc;
3098 PROC_LOCK_ASSERT(p, MA_OWNED);
3099 p->p_acflag |= AXSIG;
3101 * We must be single-threading to generate a core dump. This
3102 * ensures that the registers in the core file are up-to-date.
3103 * Also, the ELF dump handler assumes that the thread list doesn't
3104 * change out from under it.
3106 * XXX If another thread attempts to single-thread before us
3107 * (e.g. via fork()), we won't get a dump at all.
3109 if ((sigprop(sig) & SIGPROP_CORE) &&
3110 thread_single(p, SINGLE_NO_EXIT) == 0) {
3113 * Log signals which would cause core dumps
3114 * (Log as LOG_INFO to appease those who don't want
3116 * XXX : Todo, as well as euid, write out ruid too
3117 * Note that coredump() drops proc lock.
3119 if (coredump(td) == 0)
3121 if (kern_logsigexit)
3123 "pid %d (%s), uid %d: exited on signal %d%s\n",
3124 p->p_pid, p->p_comm,
3125 td->td_ucred ? td->td_ucred->cr_uid : -1,
3127 sig & WCOREFLAG ? " (core dumped)" : "");
3135 * Send queued SIGCHLD to parent when child process's state
3139 sigparent(struct proc *p, int reason, int status)
3141 PROC_LOCK_ASSERT(p, MA_OWNED);
3142 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3144 if (p->p_ksi != NULL) {
3145 p->p_ksi->ksi_signo = SIGCHLD;
3146 p->p_ksi->ksi_code = reason;
3147 p->p_ksi->ksi_status = status;
3148 p->p_ksi->ksi_pid = p->p_pid;
3149 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3150 if (KSI_ONQ(p->p_ksi))
3153 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3157 childproc_jobstate(struct proc *p, int reason, int sig)
3161 PROC_LOCK_ASSERT(p, MA_OWNED);
3162 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3165 * Wake up parent sleeping in kern_wait(), also send
3166 * SIGCHLD to parent, but SIGCHLD does not guarantee
3167 * that parent will awake, because parent may masked
3170 p->p_pptr->p_flag |= P_STATCHILD;
3173 ps = p->p_pptr->p_sigacts;
3174 mtx_lock(&ps->ps_mtx);
3175 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3176 mtx_unlock(&ps->ps_mtx);
3177 sigparent(p, reason, sig);
3179 mtx_unlock(&ps->ps_mtx);
3183 childproc_stopped(struct proc *p, int reason)
3186 childproc_jobstate(p, reason, p->p_xsig);
3190 childproc_continued(struct proc *p)
3192 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3196 childproc_exited(struct proc *p)
3200 if (WCOREDUMP(p->p_xsig)) {
3201 reason = CLD_DUMPED;
3202 status = WTERMSIG(p->p_xsig);
3203 } else if (WIFSIGNALED(p->p_xsig)) {
3204 reason = CLD_KILLED;
3205 status = WTERMSIG(p->p_xsig);
3207 reason = CLD_EXITED;
3208 status = p->p_xexit;
3211 * XXX avoid calling wakeup(p->p_pptr), the work is
3214 sigparent(p, reason, status);
3218 * We only have 1 character for the core count in the format
3219 * string, so the range will be 0-9
3221 #define MAX_NUM_CORE_FILES 10
3222 #ifndef NUM_CORE_FILES
3223 #define NUM_CORE_FILES 5
3225 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3226 static int num_cores = NUM_CORE_FILES;
3229 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3234 new_val = num_cores;
3235 error = sysctl_handle_int(oidp, &new_val, 0, req);
3236 if (error != 0 || req->newptr == NULL)
3238 if (new_val > MAX_NUM_CORE_FILES)
3239 new_val = MAX_NUM_CORE_FILES;
3242 num_cores = new_val;
3245 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3246 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3248 #define GZIP_SUFFIX ".gz"
3249 #define ZSTD_SUFFIX ".zst"
3251 int compress_user_cores = 0;
3254 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3258 val = compress_user_cores;
3259 error = sysctl_handle_int(oidp, &val, 0, req);
3260 if (error != 0 || req->newptr == NULL)
3262 if (val != 0 && !compressor_avail(val))
3264 compress_user_cores = val;
3267 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores, CTLTYPE_INT | CTLFLAG_RWTUN,
3268 0, sizeof(int), sysctl_compress_user_cores, "I",
3269 "Enable compression of user corefiles ("
3270 __XSTRING(COMPRESS_GZIP) " = gzip, "
3271 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3273 int compress_user_cores_level = 6;
3274 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3275 &compress_user_cores_level, 0,
3276 "Corefile compression level");
3279 * Protect the access to corefilename[] by allproc_lock.
3281 #define corefilename_lock allproc_lock
3283 static char corefilename[MAXPATHLEN] = {"%N.core"};
3284 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3287 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3291 sx_xlock(&corefilename_lock);
3292 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3294 sx_xunlock(&corefilename_lock);
3298 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3299 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3300 "Process corefile name format string");
3303 vnode_close_locked(struct thread *td, struct vnode *vp)
3307 vn_close(vp, FWRITE, td->td_ucred, td);
3311 * If the core format has a %I in it, then we need to check
3312 * for existing corefiles before defining a name.
3313 * To do this we iterate over 0..num_cores to find a
3314 * non-existing core file name to use. If all core files are
3315 * already used we choose the oldest one.
3318 corefile_open_last(struct thread *td, char *name, int indexpos,
3321 struct vnode *oldvp, *nextvp, *vp;
3323 struct nameidata nd;
3324 int error, i, flags, oflags, cmode;
3325 struct timespec lasttime;
3327 nextvp = oldvp = NULL;
3328 cmode = S_IRUSR | S_IWUSR;
3329 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3330 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3332 for (i = 0; i < num_cores; i++) {
3333 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3334 name[indexpos] = '0' + i;
3336 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3337 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3343 NDFREE(&nd, NDF_ONLY_PNBUF);
3344 if ((flags & O_CREAT) == O_CREAT) {
3349 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
3351 vnode_close_locked(td, vp);
3355 if (oldvp == NULL ||
3356 lasttime.tv_sec > vattr.va_mtime.tv_sec ||
3357 (lasttime.tv_sec == vattr.va_mtime.tv_sec &&
3358 lasttime.tv_nsec >= vattr.va_mtime.tv_nsec)) {
3360 vnode_close_locked(td, oldvp);
3362 lasttime = vattr.va_mtime;
3364 vnode_close_locked(td, vp);
3368 if (oldvp != NULL) {
3372 vnode_close_locked(td, oldvp);
3376 vnode_close_locked(td, oldvp);
3385 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3386 * Expand the name described in corefilename, using name, uid, and pid
3387 * and open/create core file.
3388 * corefilename is a printf-like string, with three format specifiers:
3389 * %N name of process ("name")
3390 * %P process id (pid)
3392 * For example, "%N.core" is the default; they can be disabled completely
3393 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3394 * This is controlled by the sysctl variable kern.corefile (see above).
3397 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3398 int compress, struct vnode **vpp, char **namep)
3401 struct nameidata nd;
3403 char *hostname, *name;
3404 int cmode, error, flags, i, indexpos, oflags;
3407 format = corefilename;
3408 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3410 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3411 sx_slock(&corefilename_lock);
3412 for (i = 0; format[i] != '\0'; i++) {
3413 switch (format[i]) {
3414 case '%': /* Format character */
3416 switch (format[i]) {
3418 sbuf_putc(&sb, '%');
3420 case 'H': /* hostname */
3421 if (hostname == NULL) {
3422 hostname = malloc(MAXHOSTNAMELEN,
3425 getcredhostname(td->td_ucred, hostname,
3427 sbuf_printf(&sb, "%s", hostname);
3429 case 'I': /* autoincrementing index */
3430 sbuf_printf(&sb, "0");
3431 indexpos = sbuf_len(&sb) - 1;
3433 case 'N': /* process name */
3434 sbuf_printf(&sb, "%s", comm);
3436 case 'P': /* process id */
3437 sbuf_printf(&sb, "%u", pid);
3439 case 'U': /* user id */
3440 sbuf_printf(&sb, "%u", uid);
3444 "Unknown format character %c in "
3445 "corename `%s'\n", format[i], format);
3450 sbuf_putc(&sb, format[i]);
3454 sx_sunlock(&corefilename_lock);
3455 free(hostname, M_TEMP);
3456 if (compress == COMPRESS_GZIP)
3457 sbuf_printf(&sb, GZIP_SUFFIX);
3458 else if (compress == COMPRESS_ZSTD)
3459 sbuf_printf(&sb, ZSTD_SUFFIX);
3460 if (sbuf_error(&sb) != 0) {
3461 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3462 "long\n", (long)pid, comm, (u_long)uid);
3470 if (indexpos != -1) {
3471 error = corefile_open_last(td, name, indexpos, vpp);
3474 "pid %d (%s), uid (%u): Path `%s' failed "
3475 "on initial open test, error = %d\n",
3476 pid, comm, uid, name, error);
3479 cmode = S_IRUSR | S_IWUSR;
3480 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3481 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3482 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3484 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3485 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3489 NDFREE(&nd, NDF_ONLY_PNBUF);
3495 audit_proc_coredump(td, name, error);
3505 * Dump a process' core. The main routine does some
3506 * policy checking, and creates the name of the coredump;
3507 * then it passes on a vnode and a size limit to the process-specific
3508 * coredump routine if there is one; if there _is not_ one, it returns
3509 * ENOSYS; otherwise it returns the error from the process-specific routine.
3513 coredump(struct thread *td)
3515 struct proc *p = td->td_proc;
3516 struct ucred *cred = td->td_ucred;
3520 int error, error1, locked;
3521 char *name; /* name of corefile */
3524 char *fullpath, *freepath = NULL;
3527 PROC_LOCK_ASSERT(p, MA_OWNED);
3528 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3529 _STOPEVENT(p, S_CORE, 0);
3531 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3532 (p->p_flag2 & P2_NOTRACE) != 0) {
3538 * Note that the bulk of limit checking is done after
3539 * the corefile is created. The exception is if the limit
3540 * for corefiles is 0, in which case we don't bother
3541 * creating the corefile at all. This layout means that
3542 * a corefile is truncated instead of not being created,
3543 * if it is larger than the limit.
3545 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3546 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3552 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3553 compress_user_cores, &vp, &name);
3558 * Don't dump to non-regular files or files with links.
3559 * Do not dump into system files.
3561 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3562 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0) {
3570 /* Postpone other writers, including core dumps of other processes. */
3571 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3573 lf.l_whence = SEEK_SET;
3576 lf.l_type = F_WRLCK;
3577 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3581 if (set_core_nodump_flag)
3582 vattr.va_flags = UF_NODUMP;
3583 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3584 VOP_SETATTR(vp, &vattr, cred);
3587 p->p_acflag |= ACORE;
3590 if (p->p_sysent->sv_coredump != NULL) {
3591 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3597 lf.l_type = F_UNLCK;
3598 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3600 vn_rangelock_unlock(vp, rl_cookie);
3603 * Notify the userland helper that a process triggered a core dump.
3604 * This allows the helper to run an automated debugging session.
3606 if (error != 0 || coredump_devctl == 0)
3608 sb = sbuf_new_auto();
3609 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3611 sbuf_printf(sb, "comm=\"");
3612 devctl_safe_quote_sb(sb, fullpath);
3613 free(freepath, M_TEMP);
3614 sbuf_printf(sb, "\" core=\"");
3617 * We can't lookup core file vp directly. When we're replacing a core, and
3618 * other random times, we flush the name cache, so it will fail. Instead,
3619 * if the path of the core is relative, add the current dir in front if it.
3621 if (name[0] != '/') {
3622 fullpath = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
3623 if (kern___getcwd(td, fullpath, UIO_SYSSPACE, MAXPATHLEN, MAXPATHLEN) != 0) {
3624 free(fullpath, M_TEMP);
3627 devctl_safe_quote_sb(sb, fullpath);
3628 free(fullpath, M_TEMP);
3631 devctl_safe_quote_sb(sb, name);
3632 sbuf_printf(sb, "\"");
3633 if (sbuf_finish(sb) == 0)
3634 devctl_notify("kernel", "signal", "coredump", sbuf_data(sb));
3638 error1 = vn_close(vp, FWRITE, cred, td);
3642 audit_proc_coredump(td, name, error);
3649 * Nonexistent system call-- signal process (may want to handle it). Flag
3650 * error in case process won't see signal immediately (blocked or ignored).
3652 #ifndef _SYS_SYSPROTO_H_
3659 nosys(struct thread *td, struct nosys_args *args)
3666 tdsignal(td, SIGSYS);
3668 if (kern_lognosys == 1 || kern_lognosys == 3) {
3669 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3672 if (kern_lognosys == 2 || kern_lognosys == 3) {
3673 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3680 * Send a SIGIO or SIGURG signal to a process or process group using stored
3681 * credentials rather than those of the current process.
3684 pgsigio(struct sigio **sigiop, int sig, int checkctty)
3687 struct sigio *sigio;
3689 ksiginfo_init(&ksi);
3690 ksi.ksi_signo = sig;
3691 ksi.ksi_code = SI_KERNEL;
3695 if (sigio == NULL) {
3699 if (sigio->sio_pgid > 0) {
3700 PROC_LOCK(sigio->sio_proc);
3701 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3702 kern_psignal(sigio->sio_proc, sig);
3703 PROC_UNLOCK(sigio->sio_proc);
3704 } else if (sigio->sio_pgid < 0) {
3707 PGRP_LOCK(sigio->sio_pgrp);
3708 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3710 if (p->p_state == PRS_NORMAL &&
3711 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3712 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3713 kern_psignal(p, sig);
3716 PGRP_UNLOCK(sigio->sio_pgrp);
3722 filt_sigattach(struct knote *kn)
3724 struct proc *p = curproc;
3726 kn->kn_ptr.p_proc = p;
3727 kn->kn_flags |= EV_CLEAR; /* automatically set */
3729 knlist_add(p->p_klist, kn, 0);
3735 filt_sigdetach(struct knote *kn)
3737 struct proc *p = kn->kn_ptr.p_proc;
3739 knlist_remove(p->p_klist, kn, 0);
3743 * signal knotes are shared with proc knotes, so we apply a mask to
3744 * the hint in order to differentiate them from process hints. This
3745 * could be avoided by using a signal-specific knote list, but probably
3746 * isn't worth the trouble.
3749 filt_signal(struct knote *kn, long hint)
3752 if (hint & NOTE_SIGNAL) {
3753 hint &= ~NOTE_SIGNAL;
3755 if (kn->kn_id == hint)
3758 return (kn->kn_data != 0);
3766 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3767 refcount_init(&ps->ps_refcnt, 1);
3768 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3773 sigacts_free(struct sigacts *ps)
3776 if (refcount_release(&ps->ps_refcnt) == 0)
3778 mtx_destroy(&ps->ps_mtx);
3779 free(ps, M_SUBPROC);
3783 sigacts_hold(struct sigacts *ps)
3786 refcount_acquire(&ps->ps_refcnt);
3791 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3794 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3795 mtx_lock(&src->ps_mtx);
3796 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3797 mtx_unlock(&src->ps_mtx);
3801 sigacts_shared(struct sigacts *ps)
3804 return (ps->ps_refcnt > 1);