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.
17 * 2. Redistributions in binary form must reproduce the above copyright
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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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27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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)
612 PROC_LOCK_ASSERT(p, MA_OWNED);
614 if (SIGPENDING(td)) {
616 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
622 sigonstack(size_t sp)
624 struct thread *td = curthread;
626 return ((td->td_pflags & TDP_ALTSTACK) ?
627 #if defined(COMPAT_43)
628 ((td->td_sigstk.ss_size == 0) ?
629 (td->td_sigstk.ss_flags & SS_ONSTACK) :
630 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
632 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
641 if (sig > 0 && sig < nitems(sigproptbl))
642 return (sigproptbl[sig]);
647 sig_ffs(sigset_t *set)
651 for (i = 0; i < _SIG_WORDS; i++)
653 return (ffs(set->__bits[i]) + (i * 32));
658 sigact_flag_test(const struct sigaction *act, int flag)
662 * SA_SIGINFO is reset when signal disposition is set to
663 * ignore or default. Other flags are kept according to user
666 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
667 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
668 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
678 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
679 struct sigaction *oact, int flags)
682 struct proc *p = td->td_proc;
684 if (!_SIG_VALID(sig))
686 if (act != NULL && act->sa_handler != SIG_DFL &&
687 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
688 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
689 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
694 mtx_lock(&ps->ps_mtx);
696 memset(oact, 0, sizeof(*oact));
697 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
698 if (SIGISMEMBER(ps->ps_sigonstack, sig))
699 oact->sa_flags |= SA_ONSTACK;
700 if (!SIGISMEMBER(ps->ps_sigintr, sig))
701 oact->sa_flags |= SA_RESTART;
702 if (SIGISMEMBER(ps->ps_sigreset, sig))
703 oact->sa_flags |= SA_RESETHAND;
704 if (SIGISMEMBER(ps->ps_signodefer, sig))
705 oact->sa_flags |= SA_NODEFER;
706 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
707 oact->sa_flags |= SA_SIGINFO;
709 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
711 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
712 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
713 oact->sa_flags |= SA_NOCLDSTOP;
714 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
715 oact->sa_flags |= SA_NOCLDWAIT;
718 if ((sig == SIGKILL || sig == SIGSTOP) &&
719 act->sa_handler != SIG_DFL) {
720 mtx_unlock(&ps->ps_mtx);
726 * Change setting atomically.
729 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
730 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
731 if (sigact_flag_test(act, SA_SIGINFO)) {
732 ps->ps_sigact[_SIG_IDX(sig)] =
733 (__sighandler_t *)act->sa_sigaction;
734 SIGADDSET(ps->ps_siginfo, sig);
736 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
737 SIGDELSET(ps->ps_siginfo, sig);
739 if (!sigact_flag_test(act, SA_RESTART))
740 SIGADDSET(ps->ps_sigintr, sig);
742 SIGDELSET(ps->ps_sigintr, sig);
743 if (sigact_flag_test(act, SA_ONSTACK))
744 SIGADDSET(ps->ps_sigonstack, sig);
746 SIGDELSET(ps->ps_sigonstack, sig);
747 if (sigact_flag_test(act, SA_RESETHAND))
748 SIGADDSET(ps->ps_sigreset, sig);
750 SIGDELSET(ps->ps_sigreset, sig);
751 if (sigact_flag_test(act, SA_NODEFER))
752 SIGADDSET(ps->ps_signodefer, sig);
754 SIGDELSET(ps->ps_signodefer, sig);
755 if (sig == SIGCHLD) {
756 if (act->sa_flags & SA_NOCLDSTOP)
757 ps->ps_flag |= PS_NOCLDSTOP;
759 ps->ps_flag &= ~PS_NOCLDSTOP;
760 if (act->sa_flags & SA_NOCLDWAIT) {
762 * Paranoia: since SA_NOCLDWAIT is implemented
763 * by reparenting the dying child to PID 1 (and
764 * trust it to reap the zombie), PID 1 itself
765 * is forbidden to set SA_NOCLDWAIT.
768 ps->ps_flag &= ~PS_NOCLDWAIT;
770 ps->ps_flag |= PS_NOCLDWAIT;
772 ps->ps_flag &= ~PS_NOCLDWAIT;
773 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
774 ps->ps_flag |= PS_CLDSIGIGN;
776 ps->ps_flag &= ~PS_CLDSIGIGN;
779 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
780 * and for signals set to SIG_DFL where the default is to
781 * ignore. However, don't put SIGCONT in ps_sigignore, as we
782 * have to restart the process.
784 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
785 (sigprop(sig) & SIGPROP_IGNORE &&
786 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
787 /* never to be seen again */
788 sigqueue_delete_proc(p, sig);
790 /* easier in psignal */
791 SIGADDSET(ps->ps_sigignore, sig);
792 SIGDELSET(ps->ps_sigcatch, sig);
794 SIGDELSET(ps->ps_sigignore, sig);
795 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
796 SIGDELSET(ps->ps_sigcatch, sig);
798 SIGADDSET(ps->ps_sigcatch, sig);
800 #ifdef COMPAT_FREEBSD4
801 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
802 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
803 (flags & KSA_FREEBSD4) == 0)
804 SIGDELSET(ps->ps_freebsd4, sig);
806 SIGADDSET(ps->ps_freebsd4, sig);
809 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
810 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
811 (flags & KSA_OSIGSET) == 0)
812 SIGDELSET(ps->ps_osigset, sig);
814 SIGADDSET(ps->ps_osigset, sig);
817 mtx_unlock(&ps->ps_mtx);
822 #ifndef _SYS_SYSPROTO_H_
823 struct sigaction_args {
825 struct sigaction *act;
826 struct sigaction *oact;
830 sys_sigaction(struct thread *td, struct sigaction_args *uap)
832 struct sigaction act, oact;
833 struct sigaction *actp, *oactp;
836 actp = (uap->act != NULL) ? &act : NULL;
837 oactp = (uap->oact != NULL) ? &oact : NULL;
839 error = copyin(uap->act, actp, sizeof(act));
843 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
845 error = copyout(oactp, uap->oact, sizeof(oact));
849 #ifdef COMPAT_FREEBSD4
850 #ifndef _SYS_SYSPROTO_H_
851 struct freebsd4_sigaction_args {
853 struct sigaction *act;
854 struct sigaction *oact;
858 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
860 struct sigaction act, oact;
861 struct sigaction *actp, *oactp;
865 actp = (uap->act != NULL) ? &act : NULL;
866 oactp = (uap->oact != NULL) ? &oact : NULL;
868 error = copyin(uap->act, actp, sizeof(act));
872 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
874 error = copyout(oactp, uap->oact, sizeof(oact));
877 #endif /* COMAPT_FREEBSD4 */
879 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
880 #ifndef _SYS_SYSPROTO_H_
881 struct osigaction_args {
883 struct osigaction *nsa;
884 struct osigaction *osa;
888 osigaction(struct thread *td, struct osigaction_args *uap)
890 struct osigaction sa;
891 struct sigaction nsa, osa;
892 struct sigaction *nsap, *osap;
895 if (uap->signum <= 0 || uap->signum >= ONSIG)
898 nsap = (uap->nsa != NULL) ? &nsa : NULL;
899 osap = (uap->osa != NULL) ? &osa : NULL;
902 error = copyin(uap->nsa, &sa, sizeof(sa));
905 nsap->sa_handler = sa.sa_handler;
906 nsap->sa_flags = sa.sa_flags;
907 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
909 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
910 if (osap && !error) {
911 sa.sa_handler = osap->sa_handler;
912 sa.sa_flags = osap->sa_flags;
913 SIG2OSIG(osap->sa_mask, sa.sa_mask);
914 error = copyout(&sa, uap->osa, sizeof(sa));
919 #if !defined(__i386__)
920 /* Avoid replicating the same stub everywhere */
922 osigreturn(struct thread *td, struct osigreturn_args *uap)
925 return (nosys(td, (struct nosys_args *)uap));
928 #endif /* COMPAT_43 */
931 * Initialize signal state for process 0;
932 * set to ignore signals that are ignored by default.
935 siginit(struct proc *p)
942 mtx_lock(&ps->ps_mtx);
943 for (i = 1; i <= NSIG; i++) {
944 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
945 SIGADDSET(ps->ps_sigignore, i);
948 mtx_unlock(&ps->ps_mtx);
953 * Reset specified signal to the default disposition.
956 sigdflt(struct sigacts *ps, int sig)
959 mtx_assert(&ps->ps_mtx, MA_OWNED);
960 SIGDELSET(ps->ps_sigcatch, sig);
961 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
962 SIGADDSET(ps->ps_sigignore, sig);
963 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
964 SIGDELSET(ps->ps_siginfo, sig);
968 * Reset signals for an exec of the specified process.
971 execsigs(struct proc *p)
979 * Reset caught signals. Held signals remain held
980 * through td_sigmask (unless they were caught,
981 * and are now ignored by default).
983 PROC_LOCK_ASSERT(p, MA_OWNED);
985 mtx_lock(&ps->ps_mtx);
986 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
987 sig = sig_ffs(&ps->ps_sigcatch);
989 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
990 sigqueue_delete_proc(p, sig);
994 * As CloudABI processes cannot modify signal handlers, fully
995 * reset all signals to their default behavior. Do ignore
996 * SIGPIPE, as it would otherwise be impossible to recover from
997 * writes to broken pipes and sockets.
999 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
1000 osigignore = ps->ps_sigignore;
1001 while (SIGNOTEMPTY(osigignore)) {
1002 sig = sig_ffs(&osigignore);
1003 SIGDELSET(osigignore, sig);
1007 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1011 * Reset stack state to the user stack.
1012 * Clear set of signals caught on the signal stack.
1015 MPASS(td->td_proc == p);
1016 td->td_sigstk.ss_flags = SS_DISABLE;
1017 td->td_sigstk.ss_size = 0;
1018 td->td_sigstk.ss_sp = 0;
1019 td->td_pflags &= ~TDP_ALTSTACK;
1021 * Reset no zombies if child dies flag as Solaris does.
1023 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1024 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1025 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1026 mtx_unlock(&ps->ps_mtx);
1030 * kern_sigprocmask()
1032 * Manipulate signal mask.
1035 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1038 sigset_t new_block, oset1;
1043 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1044 PROC_LOCK_ASSERT(p, MA_OWNED);
1047 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1048 ? MA_OWNED : MA_NOTOWNED);
1050 *oset = td->td_sigmask;
1057 oset1 = td->td_sigmask;
1058 SIGSETOR(td->td_sigmask, *set);
1059 new_block = td->td_sigmask;
1060 SIGSETNAND(new_block, oset1);
1063 SIGSETNAND(td->td_sigmask, *set);
1068 oset1 = td->td_sigmask;
1069 if (flags & SIGPROCMASK_OLD)
1070 SIGSETLO(td->td_sigmask, *set);
1072 td->td_sigmask = *set;
1073 new_block = td->td_sigmask;
1074 SIGSETNAND(new_block, oset1);
1083 * The new_block set contains signals that were not previously
1084 * blocked, but are blocked now.
1086 * In case we block any signal that was not previously blocked
1087 * for td, and process has the signal pending, try to schedule
1088 * signal delivery to some thread that does not block the
1089 * signal, possibly waking it up.
1091 if (p->p_numthreads != 1)
1092 reschedule_signals(p, new_block, flags);
1096 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1101 #ifndef _SYS_SYSPROTO_H_
1102 struct sigprocmask_args {
1104 const sigset_t *set;
1109 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1112 sigset_t *setp, *osetp;
1115 setp = (uap->set != NULL) ? &set : NULL;
1116 osetp = (uap->oset != NULL) ? &oset : NULL;
1118 error = copyin(uap->set, setp, sizeof(set));
1122 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1123 if (osetp && !error) {
1124 error = copyout(osetp, uap->oset, sizeof(oset));
1129 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1130 #ifndef _SYS_SYSPROTO_H_
1131 struct osigprocmask_args {
1137 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1142 OSIG2SIG(uap->mask, set);
1143 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1144 SIG2OSIG(oset, td->td_retval[0]);
1147 #endif /* COMPAT_43 */
1150 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1156 error = copyin(uap->set, &set, sizeof(set));
1158 td->td_retval[0] = error;
1162 error = kern_sigtimedwait(td, set, &ksi, NULL);
1164 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1166 if (error == ERESTART)
1168 td->td_retval[0] = error;
1172 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1173 td->td_retval[0] = error;
1178 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1181 struct timespec *timeout;
1187 error = copyin(uap->timeout, &ts, sizeof(ts));
1195 error = copyin(uap->set, &set, sizeof(set));
1199 error = kern_sigtimedwait(td, set, &ksi, timeout);
1204 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1207 td->td_retval[0] = ksi.ksi_signo;
1212 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1218 error = copyin(uap->set, &set, sizeof(set));
1222 error = kern_sigtimedwait(td, set, &ksi, NULL);
1227 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1230 td->td_retval[0] = ksi.ksi_signo;
1235 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1239 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1243 thr->td_si.si_signo = 0;
1248 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1249 struct timespec *timeout)
1252 sigset_t saved_mask, new_block;
1254 int error, sig, timo, timevalid = 0;
1255 struct timespec rts, ets, ts;
1263 if (timeout != NULL) {
1264 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1266 getnanouptime(&rts);
1268 timespecadd(&ets, timeout);
1272 /* Some signals can not be waited for. */
1273 SIG_CANTMASK(waitset);
1276 saved_mask = td->td_sigmask;
1277 SIGSETNAND(td->td_sigmask, waitset);
1279 mtx_lock(&ps->ps_mtx);
1281 mtx_unlock(&ps->ps_mtx);
1282 KASSERT(sig >= 0, ("sig %d", sig));
1283 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1284 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1285 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1295 * POSIX says this must be checked after looking for pending
1298 if (timeout != NULL) {
1303 getnanouptime(&rts);
1304 if (timespeccmp(&rts, &ets, >=)) {
1309 timespecsub(&ts, &rts);
1310 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1316 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1318 if (timeout != NULL) {
1319 if (error == ERESTART) {
1320 /* Timeout can not be restarted. */
1322 } else if (error == EAGAIN) {
1323 /* We will calculate timeout by ourself. */
1329 new_block = saved_mask;
1330 SIGSETNAND(new_block, td->td_sigmask);
1331 td->td_sigmask = saved_mask;
1333 * Fewer signals can be delivered to us, reschedule signal
1336 if (p->p_numthreads != 1)
1337 reschedule_signals(p, new_block, 0);
1340 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1342 if (ksi->ksi_code == SI_TIMER)
1343 itimer_accept(p, ksi->ksi_timerid, ksi);
1346 if (KTRPOINT(td, KTR_PSIG)) {
1349 mtx_lock(&ps->ps_mtx);
1350 action = ps->ps_sigact[_SIG_IDX(sig)];
1351 mtx_unlock(&ps->ps_mtx);
1352 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1355 if (sig == SIGKILL) {
1356 proc_td_siginfo_capture(td, &ksi->ksi_info);
1364 #ifndef _SYS_SYSPROTO_H_
1365 struct sigpending_args {
1370 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1372 struct proc *p = td->td_proc;
1376 pending = p->p_sigqueue.sq_signals;
1377 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1379 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1382 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1383 #ifndef _SYS_SYSPROTO_H_
1384 struct osigpending_args {
1389 osigpending(struct thread *td, struct osigpending_args *uap)
1391 struct proc *p = td->td_proc;
1395 pending = p->p_sigqueue.sq_signals;
1396 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1398 SIG2OSIG(pending, td->td_retval[0]);
1401 #endif /* COMPAT_43 */
1403 #if defined(COMPAT_43)
1405 * Generalized interface signal handler, 4.3-compatible.
1407 #ifndef _SYS_SYSPROTO_H_
1408 struct osigvec_args {
1416 osigvec(struct thread *td, struct osigvec_args *uap)
1419 struct sigaction nsa, osa;
1420 struct sigaction *nsap, *osap;
1423 if (uap->signum <= 0 || uap->signum >= ONSIG)
1425 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1426 osap = (uap->osv != NULL) ? &osa : NULL;
1428 error = copyin(uap->nsv, &vec, sizeof(vec));
1431 nsap->sa_handler = vec.sv_handler;
1432 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1433 nsap->sa_flags = vec.sv_flags;
1434 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1436 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1437 if (osap && !error) {
1438 vec.sv_handler = osap->sa_handler;
1439 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1440 vec.sv_flags = osap->sa_flags;
1441 vec.sv_flags &= ~SA_NOCLDWAIT;
1442 vec.sv_flags ^= SA_RESTART;
1443 error = copyout(&vec, uap->osv, sizeof(vec));
1448 #ifndef _SYS_SYSPROTO_H_
1449 struct osigblock_args {
1454 osigblock(struct thread *td, struct osigblock_args *uap)
1458 OSIG2SIG(uap->mask, set);
1459 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1460 SIG2OSIG(oset, td->td_retval[0]);
1464 #ifndef _SYS_SYSPROTO_H_
1465 struct osigsetmask_args {
1470 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1474 OSIG2SIG(uap->mask, set);
1475 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1476 SIG2OSIG(oset, td->td_retval[0]);
1479 #endif /* COMPAT_43 */
1482 * Suspend calling thread until signal, providing mask to be set in the
1485 #ifndef _SYS_SYSPROTO_H_
1486 struct sigsuspend_args {
1487 const sigset_t *sigmask;
1492 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1497 error = copyin(uap->sigmask, &mask, sizeof(mask));
1500 return (kern_sigsuspend(td, mask));
1504 kern_sigsuspend(struct thread *td, sigset_t mask)
1506 struct proc *p = td->td_proc;
1510 * When returning from sigsuspend, we want
1511 * the old mask to be restored after the
1512 * signal handler has finished. Thus, we
1513 * save it here and mark the sigacts structure
1517 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1518 SIGPROCMASK_PROC_LOCKED);
1519 td->td_pflags |= TDP_OLDMASK;
1522 * Process signals now. Otherwise, we can get spurious wakeup
1523 * due to signal entered process queue, but delivered to other
1524 * thread. But sigsuspend should return only on signal
1527 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1528 for (has_sig = 0; !has_sig;) {
1529 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1532 thread_suspend_check(0);
1533 mtx_lock(&p->p_sigacts->ps_mtx);
1534 while ((sig = cursig(td)) != 0) {
1535 KASSERT(sig >= 0, ("sig %d", sig));
1536 has_sig += postsig(sig);
1538 mtx_unlock(&p->p_sigacts->ps_mtx);
1541 td->td_errno = EINTR;
1542 td->td_pflags |= TDP_NERRNO;
1543 return (EJUSTRETURN);
1546 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1548 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1549 * convention: libc stub passes mask, not pointer, to save a copyin.
1551 #ifndef _SYS_SYSPROTO_H_
1552 struct osigsuspend_args {
1558 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1562 OSIG2SIG(uap->mask, mask);
1563 return (kern_sigsuspend(td, mask));
1565 #endif /* COMPAT_43 */
1567 #if defined(COMPAT_43)
1568 #ifndef _SYS_SYSPROTO_H_
1569 struct osigstack_args {
1570 struct sigstack *nss;
1571 struct sigstack *oss;
1576 osigstack(struct thread *td, struct osigstack_args *uap)
1578 struct sigstack nss, oss;
1581 if (uap->nss != NULL) {
1582 error = copyin(uap->nss, &nss, sizeof(nss));
1586 oss.ss_sp = td->td_sigstk.ss_sp;
1587 oss.ss_onstack = sigonstack(cpu_getstack(td));
1588 if (uap->nss != NULL) {
1589 td->td_sigstk.ss_sp = nss.ss_sp;
1590 td->td_sigstk.ss_size = 0;
1591 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1592 td->td_pflags |= TDP_ALTSTACK;
1594 if (uap->oss != NULL)
1595 error = copyout(&oss, uap->oss, sizeof(oss));
1599 #endif /* COMPAT_43 */
1601 #ifndef _SYS_SYSPROTO_H_
1602 struct sigaltstack_args {
1609 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1614 if (uap->ss != NULL) {
1615 error = copyin(uap->ss, &ss, sizeof(ss));
1619 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1620 (uap->oss != NULL) ? &oss : NULL);
1623 if (uap->oss != NULL)
1624 error = copyout(&oss, uap->oss, sizeof(stack_t));
1629 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1631 struct proc *p = td->td_proc;
1634 oonstack = sigonstack(cpu_getstack(td));
1637 *oss = td->td_sigstk;
1638 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1639 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1645 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1647 if (!(ss->ss_flags & SS_DISABLE)) {
1648 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1651 td->td_sigstk = *ss;
1652 td->td_pflags |= TDP_ALTSTACK;
1654 td->td_pflags &= ~TDP_ALTSTACK;
1661 * Common code for kill process group/broadcast kill.
1662 * cp is calling process.
1665 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1677 sx_slock(&allproc_lock);
1678 FOREACH_PROC_IN_SYSTEM(p) {
1679 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1680 p == td->td_proc || p->p_state == PRS_NEW) {
1684 err = p_cansignal(td, p, sig);
1687 pksignal(p, sig, ksi);
1690 else if (ret == ESRCH)
1694 sx_sunlock(&allproc_lock);
1696 sx_slock(&proctree_lock);
1699 * zero pgid means send to my process group.
1701 pgrp = td->td_proc->p_pgrp;
1704 pgrp = pgfind(pgid);
1706 sx_sunlock(&proctree_lock);
1710 sx_sunlock(&proctree_lock);
1711 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1713 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1714 p->p_state == PRS_NEW) {
1718 err = p_cansignal(td, p, sig);
1721 pksignal(p, sig, ksi);
1724 else if (ret == ESRCH)
1733 #ifndef _SYS_SYSPROTO_H_
1741 sys_kill(struct thread *td, struct kill_args *uap)
1748 * A process in capability mode can send signals only to himself.
1749 * The main rationale behind this is that abort(3) is implemented as
1750 * kill(getpid(), SIGABRT).
1752 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1755 AUDIT_ARG_SIGNUM(uap->signum);
1756 AUDIT_ARG_PID(uap->pid);
1757 if ((u_int)uap->signum > _SIG_MAXSIG)
1760 ksiginfo_init(&ksi);
1761 ksi.ksi_signo = uap->signum;
1762 ksi.ksi_code = SI_USER;
1763 ksi.ksi_pid = td->td_proc->p_pid;
1764 ksi.ksi_uid = td->td_ucred->cr_ruid;
1767 /* kill single process */
1768 if ((p = pfind_any(uap->pid)) == NULL)
1770 AUDIT_ARG_PROCESS(p);
1771 error = p_cansignal(td, p, uap->signum);
1772 if (error == 0 && uap->signum)
1773 pksignal(p, uap->signum, &ksi);
1778 case -1: /* broadcast signal */
1779 return (killpg1(td, uap->signum, 0, 1, &ksi));
1780 case 0: /* signal own process group */
1781 return (killpg1(td, uap->signum, 0, 0, &ksi));
1782 default: /* negative explicit process group */
1783 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1789 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1792 cap_rights_t rights;
1795 AUDIT_ARG_SIGNUM(uap->signum);
1796 AUDIT_ARG_FD(uap->fd);
1797 if ((u_int)uap->signum > _SIG_MAXSIG)
1800 error = procdesc_find(td, uap->fd,
1801 cap_rights_init(&rights, CAP_PDKILL), &p);
1804 AUDIT_ARG_PROCESS(p);
1805 error = p_cansignal(td, p, uap->signum);
1806 if (error == 0 && uap->signum)
1807 kern_psignal(p, uap->signum);
1812 #if defined(COMPAT_43)
1813 #ifndef _SYS_SYSPROTO_H_
1814 struct okillpg_args {
1821 okillpg(struct thread *td, struct okillpg_args *uap)
1825 AUDIT_ARG_SIGNUM(uap->signum);
1826 AUDIT_ARG_PID(uap->pgid);
1827 if ((u_int)uap->signum > _SIG_MAXSIG)
1830 ksiginfo_init(&ksi);
1831 ksi.ksi_signo = uap->signum;
1832 ksi.ksi_code = SI_USER;
1833 ksi.ksi_pid = td->td_proc->p_pid;
1834 ksi.ksi_uid = td->td_ucred->cr_ruid;
1835 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1837 #endif /* COMPAT_43 */
1839 #ifndef _SYS_SYSPROTO_H_
1840 struct sigqueue_args {
1843 /* union sigval */ void *value;
1847 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1851 sv.sival_ptr = uap->value;
1853 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1857 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1863 if ((u_int)signum > _SIG_MAXSIG)
1867 * Specification says sigqueue can only send signal to
1873 if ((p = pfind_any(pid)) == NULL)
1875 error = p_cansignal(td, p, signum);
1876 if (error == 0 && signum != 0) {
1877 ksiginfo_init(&ksi);
1878 ksi.ksi_flags = KSI_SIGQ;
1879 ksi.ksi_signo = signum;
1880 ksi.ksi_code = SI_QUEUE;
1881 ksi.ksi_pid = td->td_proc->p_pid;
1882 ksi.ksi_uid = td->td_ucred->cr_ruid;
1883 ksi.ksi_value = *value;
1884 error = pksignal(p, ksi.ksi_signo, &ksi);
1891 * Send a signal to a process group.
1894 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1899 sx_slock(&proctree_lock);
1900 pgrp = pgfind(pgid);
1901 sx_sunlock(&proctree_lock);
1903 pgsignal(pgrp, sig, 0, ksi);
1910 * Send a signal to a process group. If checktty is 1,
1911 * limit to members which have a controlling terminal.
1914 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1919 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1920 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1922 if (p->p_state == PRS_NORMAL &&
1923 (checkctty == 0 || p->p_flag & P_CONTROLT))
1924 pksignal(p, sig, ksi);
1932 * Recalculate the signal mask and reset the signal disposition after
1933 * usermode frame for delivery is formed. Should be called after
1934 * mach-specific routine, because sysent->sv_sendsig() needs correct
1935 * ps_siginfo and signal mask.
1938 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1942 mtx_assert(&ps->ps_mtx, MA_OWNED);
1943 td->td_ru.ru_nsignals++;
1944 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1945 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1946 SIGADDSET(mask, sig);
1947 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1948 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1949 if (SIGISMEMBER(ps->ps_sigreset, sig))
1955 * Send a signal caused by a trap to the current thread. If it will be
1956 * caught immediately, deliver it with correct code. Otherwise, post it
1960 trapsignal(struct thread *td, ksiginfo_t *ksi)
1968 sig = ksi->ksi_signo;
1969 code = ksi->ksi_code;
1970 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1974 mtx_lock(&ps->ps_mtx);
1975 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1976 !SIGISMEMBER(td->td_sigmask, sig)) {
1978 if (KTRPOINT(curthread, KTR_PSIG))
1979 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1980 &td->td_sigmask, code);
1982 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1983 ksi, &td->td_sigmask);
1984 postsig_done(sig, td, ps);
1985 mtx_unlock(&ps->ps_mtx);
1988 * Avoid a possible infinite loop if the thread
1989 * masking the signal or process is ignoring the
1992 if (kern_forcesigexit &&
1993 (SIGISMEMBER(td->td_sigmask, sig) ||
1994 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1995 SIGDELSET(td->td_sigmask, sig);
1996 SIGDELSET(ps->ps_sigcatch, sig);
1997 SIGDELSET(ps->ps_sigignore, sig);
1998 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2000 mtx_unlock(&ps->ps_mtx);
2001 p->p_code = code; /* XXX for core dump/debugger */
2002 p->p_sig = sig; /* XXX to verify code */
2003 tdsendsignal(p, td, sig, ksi);
2008 static struct thread *
2009 sigtd(struct proc *p, int sig, int prop)
2011 struct thread *td, *signal_td;
2013 PROC_LOCK_ASSERT(p, MA_OWNED);
2016 * Check if current thread can handle the signal without
2017 * switching context to another thread.
2019 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
2022 FOREACH_THREAD_IN_PROC(p, td) {
2023 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2028 if (signal_td == NULL)
2029 signal_td = FIRST_THREAD_IN_PROC(p);
2034 * Send the signal to the process. If the signal has an action, the action
2035 * is usually performed by the target process rather than the caller; we add
2036 * the signal to the set of pending signals for the process.
2039 * o When a stop signal is sent to a sleeping process that takes the
2040 * default action, the process is stopped without awakening it.
2041 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2042 * regardless of the signal action (eg, blocked or ignored).
2044 * Other ignored signals are discarded immediately.
2046 * NB: This function may be entered from the debugger via the "kill" DDB
2047 * command. There is little that can be done to mitigate the possibly messy
2048 * side effects of this unwise possibility.
2051 kern_psignal(struct proc *p, int sig)
2055 ksiginfo_init(&ksi);
2056 ksi.ksi_signo = sig;
2057 ksi.ksi_code = SI_KERNEL;
2058 (void) tdsendsignal(p, NULL, sig, &ksi);
2062 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2065 return (tdsendsignal(p, NULL, sig, ksi));
2068 /* Utility function for finding a thread to send signal event to. */
2070 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2074 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2075 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2087 tdsignal(struct thread *td, int sig)
2091 ksiginfo_init(&ksi);
2092 ksi.ksi_signo = sig;
2093 ksi.ksi_code = SI_KERNEL;
2094 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2098 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2101 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2105 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2108 sigqueue_t *sigqueue;
2115 MPASS(td == NULL || p == td->td_proc);
2116 PROC_LOCK_ASSERT(p, MA_OWNED);
2118 if (!_SIG_VALID(sig))
2119 panic("%s(): invalid signal %d", __func__, sig);
2121 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2124 * IEEE Std 1003.1-2001: return success when killing a zombie.
2126 if (p->p_state == PRS_ZOMBIE) {
2127 if (ksi && (ksi->ksi_flags & KSI_INS))
2128 ksiginfo_tryfree(ksi);
2133 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2134 prop = sigprop(sig);
2137 td = sigtd(p, sig, prop);
2138 sigqueue = &p->p_sigqueue;
2140 sigqueue = &td->td_sigqueue;
2142 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2145 * If the signal is being ignored,
2146 * then we forget about it immediately.
2147 * (Note: we don't set SIGCONT in ps_sigignore,
2148 * and if it is set to SIG_IGN,
2149 * action will be SIG_DFL here.)
2151 mtx_lock(&ps->ps_mtx);
2152 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2153 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2155 mtx_unlock(&ps->ps_mtx);
2156 if (ksi && (ksi->ksi_flags & KSI_INS))
2157 ksiginfo_tryfree(ksi);
2160 if (SIGISMEMBER(td->td_sigmask, sig))
2162 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2166 if (SIGISMEMBER(ps->ps_sigintr, sig))
2170 mtx_unlock(&ps->ps_mtx);
2172 if (prop & SIGPROP_CONT)
2173 sigqueue_delete_stopmask_proc(p);
2174 else if (prop & SIGPROP_STOP) {
2176 * If sending a tty stop signal to a member of an orphaned
2177 * process group, discard the signal here if the action
2178 * is default; don't stop the process below if sleeping,
2179 * and don't clear any pending SIGCONT.
2181 if ((prop & SIGPROP_TTYSTOP) &&
2182 (p->p_pgrp->pg_jobc == 0) &&
2183 (action == SIG_DFL)) {
2184 if (ksi && (ksi->ksi_flags & KSI_INS))
2185 ksiginfo_tryfree(ksi);
2188 sigqueue_delete_proc(p, SIGCONT);
2189 if (p->p_flag & P_CONTINUED) {
2190 p->p_flag &= ~P_CONTINUED;
2191 PROC_LOCK(p->p_pptr);
2192 sigqueue_take(p->p_ksi);
2193 PROC_UNLOCK(p->p_pptr);
2197 ret = sigqueue_add(sigqueue, sig, ksi);
2202 * Defer further processing for signals which are held,
2203 * except that stopped processes must be continued by SIGCONT.
2205 if (action == SIG_HOLD &&
2206 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2209 /* SIGKILL: Remove procfs STOPEVENTs. */
2210 if (sig == SIGKILL) {
2211 /* from procfs_ioctl.c: PIOCBIC */
2213 /* from procfs_ioctl.c: PIOCCONT */
2218 * Some signals have a process-wide effect and a per-thread
2219 * component. Most processing occurs when the process next
2220 * tries to cross the user boundary, however there are some
2221 * times when processing needs to be done immediately, such as
2222 * waking up threads so that they can cross the user boundary.
2223 * We try to do the per-process part here.
2225 if (P_SHOULDSTOP(p)) {
2226 KASSERT(!(p->p_flag & P_WEXIT),
2227 ("signal to stopped but exiting process"));
2228 if (sig == SIGKILL) {
2230 * If traced process is already stopped,
2231 * then no further action is necessary.
2233 if (p->p_flag & P_TRACED)
2236 * SIGKILL sets process running.
2237 * It will die elsewhere.
2238 * All threads must be restarted.
2240 p->p_flag &= ~P_STOPPED_SIG;
2244 if (prop & SIGPROP_CONT) {
2246 * If traced process is already stopped,
2247 * then no further action is necessary.
2249 if (p->p_flag & P_TRACED)
2252 * If SIGCONT is default (or ignored), we continue the
2253 * process but don't leave the signal in sigqueue as
2254 * it has no further action. If SIGCONT is held, we
2255 * continue the process and leave the signal in
2256 * sigqueue. If the process catches SIGCONT, let it
2257 * handle the signal itself. If it isn't waiting on
2258 * an event, it goes back to run state.
2259 * Otherwise, process goes back to sleep state.
2261 p->p_flag &= ~P_STOPPED_SIG;
2263 if (p->p_numthreads == p->p_suspcount) {
2265 p->p_flag |= P_CONTINUED;
2266 p->p_xsig = SIGCONT;
2267 PROC_LOCK(p->p_pptr);
2268 childproc_continued(p);
2269 PROC_UNLOCK(p->p_pptr);
2272 if (action == SIG_DFL) {
2273 thread_unsuspend(p);
2275 sigqueue_delete(sigqueue, sig);
2278 if (action == SIG_CATCH) {
2280 * The process wants to catch it so it needs
2281 * to run at least one thread, but which one?
2287 * The signal is not ignored or caught.
2289 thread_unsuspend(p);
2294 if (prop & SIGPROP_STOP) {
2296 * If traced process is already stopped,
2297 * then no further action is necessary.
2299 if (p->p_flag & P_TRACED)
2302 * Already stopped, don't need to stop again
2303 * (If we did the shell could get confused).
2304 * Just make sure the signal STOP bit set.
2306 p->p_flag |= P_STOPPED_SIG;
2307 sigqueue_delete(sigqueue, sig);
2312 * All other kinds of signals:
2313 * If a thread is sleeping interruptibly, simulate a
2314 * wakeup so that when it is continued it will be made
2315 * runnable and can look at the signal. However, don't make
2316 * the PROCESS runnable, leave it stopped.
2317 * It may run a bit until it hits a thread_suspend_check().
2322 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2323 wakeup_swapper = sleepq_abort(td, intrval);
2330 * Mutexes are short lived. Threads waiting on them will
2331 * hit thread_suspend_check() soon.
2333 } else if (p->p_state == PRS_NORMAL) {
2334 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2335 tdsigwakeup(td, sig, action, intrval);
2339 MPASS(action == SIG_DFL);
2341 if (prop & SIGPROP_STOP) {
2342 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2344 p->p_flag |= P_STOPPED_SIG;
2347 wakeup_swapper = sig_suspend_threads(td, p, 1);
2348 if (p->p_numthreads == p->p_suspcount) {
2350 * only thread sending signal to another
2351 * process can reach here, if thread is sending
2352 * signal to its process, because thread does
2353 * not suspend itself here, p_numthreads
2354 * should never be equal to p_suspcount.
2358 sigqueue_delete_proc(p, p->p_xsig);
2366 /* Not in "NORMAL" state. discard the signal. */
2367 sigqueue_delete(sigqueue, sig);
2372 * The process is not stopped so we need to apply the signal to all the
2376 tdsigwakeup(td, sig, action, intrval);
2378 thread_unsuspend(p);
2381 /* If we jump here, proc slock should not be owned. */
2382 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2387 * The force of a signal has been directed against a single
2388 * thread. We need to see what we can do about knocking it
2389 * out of any sleep it may be in etc.
2392 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2394 struct proc *p = td->td_proc;
2399 PROC_LOCK_ASSERT(p, MA_OWNED);
2400 prop = sigprop(sig);
2405 * Bring the priority of a thread up if we want it to get
2406 * killed in this lifetime. Be careful to avoid bumping the
2407 * priority of the idle thread, since we still allow to signal
2410 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2411 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2412 sched_prio(td, PUSER);
2413 if (TD_ON_SLEEPQ(td)) {
2415 * If thread is sleeping uninterruptibly
2416 * we can't interrupt the sleep... the signal will
2417 * be noticed when the process returns through
2418 * trap() or syscall().
2420 if ((td->td_flags & TDF_SINTR) == 0)
2423 * If SIGCONT is default (or ignored) and process is
2424 * asleep, we are finished; the process should not
2427 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2430 sigqueue_delete(&p->p_sigqueue, sig);
2432 * It may be on either list in this state.
2433 * Remove from both for now.
2435 sigqueue_delete(&td->td_sigqueue, sig);
2440 * Don't awaken a sleeping thread for SIGSTOP if the
2441 * STOP signal is deferred.
2443 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2444 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2448 * Give low priority threads a better chance to run.
2450 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2451 sched_prio(td, PUSER);
2453 wakeup_swapper = sleepq_abort(td, intrval);
2456 * Other states do nothing with the signal immediately,
2457 * other than kicking ourselves if we are running.
2458 * It will either never be noticed, or noticed very soon.
2461 if (TD_IS_RUNNING(td) && td != curthread)
2473 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2478 PROC_LOCK_ASSERT(p, MA_OWNED);
2479 PROC_SLOCK_ASSERT(p, MA_OWNED);
2480 MPASS(sending || td == curthread);
2483 FOREACH_THREAD_IN_PROC(p, td2) {
2485 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2486 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2487 (td2->td_flags & TDF_SINTR)) {
2488 if (td2->td_flags & TDF_SBDRY) {
2490 * Once a thread is asleep with
2491 * TDF_SBDRY and without TDF_SERESTART
2492 * or TDF_SEINTR set, it should never
2493 * become suspended due to this check.
2495 KASSERT(!TD_IS_SUSPENDED(td2),
2496 ("thread with deferred stops suspended"));
2497 if (TD_SBDRY_INTR(td2))
2498 wakeup_swapper |= sleepq_abort(td2,
2499 TD_SBDRY_ERRNO(td2));
2500 } else if (!TD_IS_SUSPENDED(td2)) {
2501 thread_suspend_one(td2);
2503 } else if (!TD_IS_SUSPENDED(td2)) {
2504 if (sending || td != td2)
2505 td2->td_flags |= TDF_ASTPENDING;
2507 if (TD_IS_RUNNING(td2) && td2 != td)
2508 forward_signal(td2);
2513 return (wakeup_swapper);
2517 * Stop the process for an event deemed interesting to the debugger. If si is
2518 * non-NULL, this is a signal exchange; the new signal requested by the
2519 * debugger will be returned for handling. If si is NULL, this is some other
2520 * type of interesting event. The debugger may request a signal be delivered in
2521 * that case as well, however it will be deferred until it can be handled.
2524 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2526 struct proc *p = td->td_proc;
2531 PROC_LOCK_ASSERT(p, MA_OWNED);
2532 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2533 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2534 &p->p_mtx.lock_object, "Stopping for traced signal");
2538 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2539 td->td_dbgflags |= TDB_XSIG;
2540 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2541 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2543 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2546 * Ensure that, if we've been PT_KILLed, the
2547 * exit status reflects that. Another thread
2548 * may also be in ptracestop(), having just
2549 * received the SIGKILL, but this thread was
2550 * unsuspended first.
2552 td->td_dbgflags &= ~TDB_XSIG;
2553 td->td_xsig = SIGKILL;
2557 if (p->p_flag & P_SINGLE_EXIT &&
2558 !(td->td_dbgflags & TDB_EXIT)) {
2560 * Ignore ptrace stops except for thread exit
2561 * events when the process exits.
2563 td->td_dbgflags &= ~TDB_XSIG;
2569 * Make wait(2) work. Ensure that right after the
2570 * attach, the thread which was decided to become the
2571 * leader of attach gets reported to the waiter.
2572 * Otherwise, just avoid overwriting another thread's
2573 * assignment to p_xthread. If another thread has
2574 * already set p_xthread, the current thread will get
2575 * a chance to report itself upon the next iteration.
2577 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2578 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2579 p->p_xthread == NULL)) {
2582 td->td_dbgflags &= ~TDB_FSTP;
2583 p->p_flag2 &= ~P2_PTRACE_FSTP;
2584 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2585 sig_suspend_threads(td, p, 0);
2587 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2588 td->td_dbgflags &= ~TDB_STOPATFORK;
2589 cv_broadcast(&p->p_dbgwait);
2592 thread_suspend_switch(td, p);
2593 if (p->p_xthread == td)
2594 p->p_xthread = NULL;
2595 if (!(p->p_flag & P_TRACED))
2597 if (td->td_dbgflags & TDB_SUSPEND) {
2598 if (p->p_flag & P_SINGLE_EXIT)
2606 if (si != NULL && sig == td->td_xsig) {
2607 /* Parent wants us to take the original signal unchanged. */
2608 si->ksi_flags |= KSI_HEAD;
2609 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2611 } else if (td->td_xsig != 0) {
2613 * If parent wants us to take a new signal, then it will leave
2614 * it in td->td_xsig; otherwise we just look for signals again.
2616 ksiginfo_init(&ksi);
2617 ksi.ksi_signo = td->td_xsig;
2618 ksi.ksi_flags |= KSI_PTRACE;
2619 prop = sigprop(td->td_xsig);
2620 td2 = sigtd(p, td->td_xsig, prop);
2621 tdsendsignal(p, td2, td->td_xsig, &ksi);
2626 return (td->td_xsig);
2630 reschedule_signals(struct proc *p, sigset_t block, int flags)
2636 PROC_LOCK_ASSERT(p, MA_OWNED);
2638 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2639 MA_OWNED : MA_NOTOWNED);
2640 if (SIGISEMPTY(p->p_siglist))
2642 SIGSETAND(block, p->p_siglist);
2643 while ((sig = sig_ffs(&block)) != 0) {
2644 SIGDELSET(block, sig);
2645 td = sigtd(p, sig, 0);
2647 if (!(flags & SIGPROCMASK_PS_LOCKED))
2648 mtx_lock(&ps->ps_mtx);
2649 if (p->p_flag & P_TRACED ||
2650 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2651 !SIGISMEMBER(td->td_sigmask, sig)))
2652 tdsigwakeup(td, sig, SIG_CATCH,
2653 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2655 if (!(flags & SIGPROCMASK_PS_LOCKED))
2656 mtx_unlock(&ps->ps_mtx);
2661 tdsigcleanup(struct thread *td)
2667 PROC_LOCK_ASSERT(p, MA_OWNED);
2669 sigqueue_flush(&td->td_sigqueue);
2670 if (p->p_numthreads == 1)
2674 * Since we cannot handle signals, notify signal post code
2675 * about this by filling the sigmask.
2677 * Also, if needed, wake up thread(s) that do not block the
2678 * same signals as the exiting thread, since the thread might
2679 * have been selected for delivery and woken up.
2681 SIGFILLSET(unblocked);
2682 SIGSETNAND(unblocked, td->td_sigmask);
2683 SIGFILLSET(td->td_sigmask);
2684 reschedule_signals(p, unblocked, 0);
2689 sigdeferstop_curr_flags(int cflags)
2692 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2693 (cflags & TDF_SBDRY) != 0);
2694 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2698 * Defer the delivery of SIGSTOP for the current thread, according to
2699 * the requested mode. Returns previous flags, which must be restored
2700 * by sigallowstop().
2702 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2703 * cleared by the current thread, which allow the lock-less read-only
2707 sigdeferstop_impl(int mode)
2713 cflags = sigdeferstop_curr_flags(td->td_flags);
2715 case SIGDEFERSTOP_NOP:
2718 case SIGDEFERSTOP_OFF:
2721 case SIGDEFERSTOP_SILENT:
2722 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2724 case SIGDEFERSTOP_EINTR:
2725 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2727 case SIGDEFERSTOP_ERESTART:
2728 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2731 panic("sigdeferstop: invalid mode %x", mode);
2734 if (cflags == nflags)
2735 return (SIGDEFERSTOP_VAL_NCHG);
2737 td->td_flags = (td->td_flags & ~cflags) | nflags;
2743 * Restores the STOP handling mode, typically permitting the delivery
2744 * of SIGSTOP for the current thread. This does not immediately
2745 * suspend if a stop was posted. Instead, the thread will suspend
2746 * either via ast() or a subsequent interruptible sleep.
2749 sigallowstop_impl(int prev)
2754 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2755 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2756 ("sigallowstop: incorrect previous mode %x", prev));
2758 cflags = sigdeferstop_curr_flags(td->td_flags);
2759 if (cflags != prev) {
2761 td->td_flags = (td->td_flags & ~cflags) | prev;
2767 * If the current process has received a signal (should be caught or cause
2768 * termination, should interrupt current syscall), return the signal number.
2769 * Stop signals with default action are processed immediately, then cleared;
2770 * they aren't returned. This is checked after each entry to the system for
2771 * a syscall or trap (though this can usually be done without calling issignal
2772 * by checking the pending signal masks in cursig.) The normal call
2775 * while (sig = cursig(curthread))
2779 issignal(struct thread *td)
2783 struct sigqueue *queue;
2784 sigset_t sigpending;
2786 int prop, sig, traced;
2790 mtx_assert(&ps->ps_mtx, MA_OWNED);
2791 PROC_LOCK_ASSERT(p, MA_OWNED);
2793 traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2795 sigpending = td->td_sigqueue.sq_signals;
2796 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2797 SIGSETNAND(sigpending, td->td_sigmask);
2799 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
2800 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2801 SIG_STOPSIGMASK(sigpending);
2802 if (SIGISEMPTY(sigpending)) /* no signal to send */
2804 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2805 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2806 SIGISMEMBER(sigpending, SIGSTOP)) {
2808 * If debugger just attached, always consume
2809 * SIGSTOP from ptrace(PT_ATTACH) first, to
2810 * execute the debugger attach ritual in
2814 td->td_dbgflags |= TDB_FSTP;
2816 sig = sig_ffs(&sigpending);
2819 if (p->p_stops & S_SIG) {
2820 mtx_unlock(&ps->ps_mtx);
2821 stopevent(p, S_SIG, sig);
2822 mtx_lock(&ps->ps_mtx);
2826 * We should see pending but ignored signals
2827 * only if P_TRACED was on when they were posted.
2829 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2830 sigqueue_delete(&td->td_sigqueue, sig);
2831 sigqueue_delete(&p->p_sigqueue, sig);
2834 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2836 * If traced, always stop.
2837 * Remove old signal from queue before the stop.
2838 * XXX shrug off debugger, it causes siginfo to
2841 queue = &td->td_sigqueue;
2842 ksiginfo_init(&ksi);
2843 if (sigqueue_get(queue, sig, &ksi) == 0) {
2844 queue = &p->p_sigqueue;
2845 sigqueue_get(queue, sig, &ksi);
2847 td->td_si = ksi.ksi_info;
2849 mtx_unlock(&ps->ps_mtx);
2850 sig = ptracestop(td, sig, &ksi);
2851 mtx_lock(&ps->ps_mtx);
2854 * Keep looking if the debugger discarded or
2855 * replaced the signal.
2861 * If the signal became masked, re-queue it.
2863 if (SIGISMEMBER(td->td_sigmask, sig)) {
2864 ksi.ksi_flags |= KSI_HEAD;
2865 sigqueue_add(&p->p_sigqueue, sig, &ksi);
2870 * If the traced bit got turned off, requeue
2871 * the signal and go back up to the top to
2872 * rescan signals. This ensures that p_sig*
2873 * and p_sigact are consistent.
2875 if ((p->p_flag & P_TRACED) == 0) {
2876 ksi.ksi_flags |= KSI_HEAD;
2877 sigqueue_add(queue, sig, &ksi);
2882 prop = sigprop(sig);
2885 * Decide whether the signal should be returned.
2886 * Return the signal's number, or fall through
2887 * to clear it from the pending mask.
2889 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2891 case (intptr_t)SIG_DFL:
2893 * Don't take default actions on system processes.
2895 if (p->p_pid <= 1) {
2898 * Are you sure you want to ignore SIGSEGV
2901 printf("Process (pid %lu) got signal %d\n",
2902 (u_long)p->p_pid, sig);
2904 break; /* == ignore */
2907 * If there is a pending stop signal to process with
2908 * default action, stop here, then clear the signal.
2909 * Traced or exiting processes should ignore stops.
2910 * Additionally, a member of an orphaned process group
2911 * should ignore tty stops.
2913 if (prop & SIGPROP_STOP) {
2915 (P_TRACED | P_WEXIT | P_SINGLE_EXIT) ||
2916 (p->p_pgrp->pg_jobc == 0 &&
2917 prop & SIGPROP_TTYSTOP))
2918 break; /* == ignore */
2919 if (TD_SBDRY_INTR(td)) {
2920 KASSERT((td->td_flags & TDF_SBDRY) != 0,
2921 ("lost TDF_SBDRY"));
2924 mtx_unlock(&ps->ps_mtx);
2925 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2926 &p->p_mtx.lock_object, "Catching SIGSTOP");
2927 sigqueue_delete(&td->td_sigqueue, sig);
2928 sigqueue_delete(&p->p_sigqueue, sig);
2929 p->p_flag |= P_STOPPED_SIG;
2932 sig_suspend_threads(td, p, 0);
2933 thread_suspend_switch(td, p);
2935 mtx_lock(&ps->ps_mtx);
2937 } else if (prop & SIGPROP_IGNORE) {
2939 * Except for SIGCONT, shouldn't get here.
2940 * Default action is to ignore; drop it.
2942 break; /* == ignore */
2947 case (intptr_t)SIG_IGN:
2949 * Masking above should prevent us ever trying
2950 * to take action on an ignored signal other
2951 * than SIGCONT, unless process is traced.
2953 if ((prop & SIGPROP_CONT) == 0 &&
2954 (p->p_flag & P_TRACED) == 0)
2955 printf("issignal\n");
2956 break; /* == ignore */
2960 * This signal has an action, let
2961 * postsig() process it.
2965 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2966 sigqueue_delete(&p->p_sigqueue, sig);
2973 thread_stopped(struct proc *p)
2977 PROC_LOCK_ASSERT(p, MA_OWNED);
2978 PROC_SLOCK_ASSERT(p, MA_OWNED);
2982 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2984 p->p_flag &= ~P_WAITED;
2985 PROC_LOCK(p->p_pptr);
2986 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2987 CLD_TRAPPED : CLD_STOPPED);
2988 PROC_UNLOCK(p->p_pptr);
2994 * Take the action for the specified signal
2995 * from the current set of pending signals.
3005 sigset_t returnmask;
3007 KASSERT(sig != 0, ("postsig"));
3011 PROC_LOCK_ASSERT(p, MA_OWNED);
3013 mtx_assert(&ps->ps_mtx, MA_OWNED);
3014 ksiginfo_init(&ksi);
3015 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3016 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3018 ksi.ksi_signo = sig;
3019 if (ksi.ksi_code == SI_TIMER)
3020 itimer_accept(p, ksi.ksi_timerid, &ksi);
3021 action = ps->ps_sigact[_SIG_IDX(sig)];
3023 if (KTRPOINT(td, KTR_PSIG))
3024 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3025 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3027 if ((p->p_stops & S_SIG) != 0) {
3028 mtx_unlock(&ps->ps_mtx);
3029 stopevent(p, S_SIG, sig);
3030 mtx_lock(&ps->ps_mtx);
3033 if (action == SIG_DFL) {
3035 * Default action, where the default is to kill
3036 * the process. (Other cases were ignored above.)
3038 mtx_unlock(&ps->ps_mtx);
3039 proc_td_siginfo_capture(td, &ksi.ksi_info);
3044 * If we get here, the signal must be caught.
3046 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3047 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3048 ("postsig action: blocked sig %d", sig));
3051 * Set the new mask value and also defer further
3052 * occurrences of this signal.
3054 * Special case: user has done a sigsuspend. Here the
3055 * current mask is not of interest, but rather the
3056 * mask from before the sigsuspend is what we want
3057 * restored after the signal processing is completed.
3059 if (td->td_pflags & TDP_OLDMASK) {
3060 returnmask = td->td_oldsigmask;
3061 td->td_pflags &= ~TDP_OLDMASK;
3063 returnmask = td->td_sigmask;
3065 if (p->p_sig == sig) {
3069 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3070 postsig_done(sig, td, ps);
3076 * Kill the current process for stated reason.
3079 killproc(struct proc *p, char *why)
3082 PROC_LOCK_ASSERT(p, MA_OWNED);
3083 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3085 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
3086 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
3087 p->p_flag |= P_WKILLED;
3088 kern_psignal(p, SIGKILL);
3092 * Force the current process to exit with the specified signal, dumping core
3093 * if appropriate. We bypass the normal tests for masked and caught signals,
3094 * allowing unrecoverable failures to terminate the process without changing
3095 * signal state. Mark the accounting record with the signal termination.
3096 * If dumping core, save the signal number for the debugger. Calls exit and
3100 sigexit(struct thread *td, int sig)
3102 struct proc *p = td->td_proc;
3104 PROC_LOCK_ASSERT(p, MA_OWNED);
3105 p->p_acflag |= AXSIG;
3107 * We must be single-threading to generate a core dump. This
3108 * ensures that the registers in the core file are up-to-date.
3109 * Also, the ELF dump handler assumes that the thread list doesn't
3110 * change out from under it.
3112 * XXX If another thread attempts to single-thread before us
3113 * (e.g. via fork()), we won't get a dump at all.
3115 if ((sigprop(sig) & SIGPROP_CORE) &&
3116 thread_single(p, SINGLE_NO_EXIT) == 0) {
3119 * Log signals which would cause core dumps
3120 * (Log as LOG_INFO to appease those who don't want
3122 * XXX : Todo, as well as euid, write out ruid too
3123 * Note that coredump() drops proc lock.
3125 if (coredump(td) == 0)
3127 if (kern_logsigexit)
3129 "pid %d (%s), uid %d: exited on signal %d%s\n",
3130 p->p_pid, p->p_comm,
3131 td->td_ucred ? td->td_ucred->cr_uid : -1,
3133 sig & WCOREFLAG ? " (core dumped)" : "");
3141 * Send queued SIGCHLD to parent when child process's state
3145 sigparent(struct proc *p, int reason, int status)
3147 PROC_LOCK_ASSERT(p, MA_OWNED);
3148 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3150 if (p->p_ksi != NULL) {
3151 p->p_ksi->ksi_signo = SIGCHLD;
3152 p->p_ksi->ksi_code = reason;
3153 p->p_ksi->ksi_status = status;
3154 p->p_ksi->ksi_pid = p->p_pid;
3155 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3156 if (KSI_ONQ(p->p_ksi))
3159 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3163 childproc_jobstate(struct proc *p, int reason, int sig)
3167 PROC_LOCK_ASSERT(p, MA_OWNED);
3168 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3171 * Wake up parent sleeping in kern_wait(), also send
3172 * SIGCHLD to parent, but SIGCHLD does not guarantee
3173 * that parent will awake, because parent may masked
3176 p->p_pptr->p_flag |= P_STATCHILD;
3179 ps = p->p_pptr->p_sigacts;
3180 mtx_lock(&ps->ps_mtx);
3181 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3182 mtx_unlock(&ps->ps_mtx);
3183 sigparent(p, reason, sig);
3185 mtx_unlock(&ps->ps_mtx);
3189 childproc_stopped(struct proc *p, int reason)
3192 childproc_jobstate(p, reason, p->p_xsig);
3196 childproc_continued(struct proc *p)
3198 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3202 childproc_exited(struct proc *p)
3206 if (WCOREDUMP(p->p_xsig)) {
3207 reason = CLD_DUMPED;
3208 status = WTERMSIG(p->p_xsig);
3209 } else if (WIFSIGNALED(p->p_xsig)) {
3210 reason = CLD_KILLED;
3211 status = WTERMSIG(p->p_xsig);
3213 reason = CLD_EXITED;
3214 status = p->p_xexit;
3217 * XXX avoid calling wakeup(p->p_pptr), the work is
3220 sigparent(p, reason, status);
3224 * We only have 1 character for the core count in the format
3225 * string, so the range will be 0-9
3227 #define MAX_NUM_CORE_FILES 10
3228 #ifndef NUM_CORE_FILES
3229 #define NUM_CORE_FILES 5
3231 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3232 static int num_cores = NUM_CORE_FILES;
3235 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3240 new_val = num_cores;
3241 error = sysctl_handle_int(oidp, &new_val, 0, req);
3242 if (error != 0 || req->newptr == NULL)
3244 if (new_val > MAX_NUM_CORE_FILES)
3245 new_val = MAX_NUM_CORE_FILES;
3248 num_cores = new_val;
3251 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3252 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3254 #define GZIP_SUFFIX ".gz"
3255 #define ZSTD_SUFFIX ".zst"
3257 int compress_user_cores = 0;
3260 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3264 val = compress_user_cores;
3265 error = sysctl_handle_int(oidp, &val, 0, req);
3266 if (error != 0 || req->newptr == NULL)
3268 if (val != 0 && !compressor_avail(val))
3270 compress_user_cores = val;
3273 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores, CTLTYPE_INT | CTLFLAG_RWTUN,
3274 0, sizeof(int), sysctl_compress_user_cores, "I",
3275 "Enable compression of user corefiles ("
3276 __XSTRING(COMPRESS_GZIP) " = gzip, "
3277 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3279 int compress_user_cores_level = 6;
3280 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3281 &compress_user_cores_level, 0,
3282 "Corefile compression level");
3285 * Protect the access to corefilename[] by allproc_lock.
3287 #define corefilename_lock allproc_lock
3289 static char corefilename[MAXPATHLEN] = {"%N.core"};
3290 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3293 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3297 sx_xlock(&corefilename_lock);
3298 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3300 sx_xunlock(&corefilename_lock);
3304 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3305 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3306 "Process corefile name format string");
3309 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3310 * Expand the name described in corefilename, using name, uid, and pid
3311 * and open/create core file.
3312 * corefilename is a printf-like string, with three format specifiers:
3313 * %N name of process ("name")
3314 * %P process id (pid)
3316 * For example, "%N.core" is the default; they can be disabled completely
3317 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3318 * This is controlled by the sysctl variable kern.corefile (see above).
3321 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3322 int compress, struct vnode **vpp, char **namep)
3324 struct nameidata nd;
3327 char *hostname, *name;
3328 int indexpos, i, error, cmode, flags, oflags;
3331 format = corefilename;
3332 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3334 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3335 sx_slock(&corefilename_lock);
3336 for (i = 0; format[i] != '\0'; i++) {
3337 switch (format[i]) {
3338 case '%': /* Format character */
3340 switch (format[i]) {
3342 sbuf_putc(&sb, '%');
3344 case 'H': /* hostname */
3345 if (hostname == NULL) {
3346 hostname = malloc(MAXHOSTNAMELEN,
3349 getcredhostname(td->td_ucred, hostname,
3351 sbuf_printf(&sb, "%s", hostname);
3353 case 'I': /* autoincrementing index */
3354 sbuf_printf(&sb, "0");
3355 indexpos = sbuf_len(&sb) - 1;
3357 case 'N': /* process name */
3358 sbuf_printf(&sb, "%s", comm);
3360 case 'P': /* process id */
3361 sbuf_printf(&sb, "%u", pid);
3363 case 'U': /* user id */
3364 sbuf_printf(&sb, "%u", uid);
3368 "Unknown format character %c in "
3369 "corename `%s'\n", format[i], format);
3374 sbuf_putc(&sb, format[i]);
3378 sx_sunlock(&corefilename_lock);
3379 free(hostname, M_TEMP);
3380 if (compress == COMPRESS_GZIP)
3381 sbuf_printf(&sb, GZIP_SUFFIX);
3382 else if (compress == COMPRESS_ZSTD)
3383 sbuf_printf(&sb, ZSTD_SUFFIX);
3384 if (sbuf_error(&sb) != 0) {
3385 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3386 "long\n", (long)pid, comm, (u_long)uid);
3394 cmode = S_IRUSR | S_IWUSR;
3395 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3396 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3399 * If the core format has a %I in it, then we need to check
3400 * for existing corefiles before returning a name.
3401 * To do this we iterate over 0..num_cores to find a
3402 * non-existing core file name to use.
3404 if (indexpos != -1) {
3405 for (i = 0; i < num_cores; i++) {
3406 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3407 name[indexpos] = '0' + i;
3408 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3409 error = vn_open_cred(&nd, &flags, cmode, oflags,
3410 td->td_ucred, NULL);
3412 if (error == EEXIST)
3415 "pid %d (%s), uid (%u): Path `%s' failed "
3416 "on initial open test, error = %d\n",
3417 pid, comm, uid, name, error);
3423 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3424 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3425 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3429 audit_proc_coredump(td, name, error);
3434 NDFREE(&nd, NDF_ONLY_PNBUF);
3441 coredump_sanitise_path(const char *path)
3446 * Only send a subset of ASCII to devd(8) because it
3447 * might pass these strings to sh -c.
3449 for (i = 0; path[i]; i++)
3450 if (!(isalpha(path[i]) || isdigit(path[i])) &&
3451 path[i] != '/' && path[i] != '.' &&
3459 * Dump a process' core. The main routine does some
3460 * policy checking, and creates the name of the coredump;
3461 * then it passes on a vnode and a size limit to the process-specific
3462 * coredump routine if there is one; if there _is not_ one, it returns
3463 * ENOSYS; otherwise it returns the error from the process-specific routine.
3467 coredump(struct thread *td)
3469 struct proc *p = td->td_proc;
3470 struct ucred *cred = td->td_ucred;
3474 int error, error1, locked;
3475 char *name; /* name of corefile */
3479 char *fullpath, *freepath = NULL;
3481 static const char comm_name[] = "comm=";
3482 static const char core_name[] = "core=";
3484 PROC_LOCK_ASSERT(p, MA_OWNED);
3485 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3486 _STOPEVENT(p, S_CORE, 0);
3488 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3489 (p->p_flag2 & P2_NOTRACE) != 0) {
3495 * Note that the bulk of limit checking is done after
3496 * the corefile is created. The exception is if the limit
3497 * for corefiles is 0, in which case we don't bother
3498 * creating the corefile at all. This layout means that
3499 * a corefile is truncated instead of not being created,
3500 * if it is larger than the limit.
3502 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3503 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3509 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3510 compress_user_cores, &vp, &name);
3515 * Don't dump to non-regular files or files with links.
3516 * Do not dump into system files.
3518 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3519 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0) {
3527 /* Postpone other writers, including core dumps of other processes. */
3528 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3530 lf.l_whence = SEEK_SET;
3533 lf.l_type = F_WRLCK;
3534 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3538 if (set_core_nodump_flag)
3539 vattr.va_flags = UF_NODUMP;
3540 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3541 VOP_SETATTR(vp, &vattr, cred);
3544 p->p_acflag |= ACORE;
3547 if (p->p_sysent->sv_coredump != NULL) {
3548 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3554 lf.l_type = F_UNLCK;
3555 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3557 vn_rangelock_unlock(vp, rl_cookie);
3560 * Notify the userland helper that a process triggered a core dump.
3561 * This allows the helper to run an automated debugging session.
3563 if (error != 0 || coredump_devctl == 0)
3565 len = MAXPATHLEN * 2 + sizeof(comm_name) - 1 +
3566 sizeof(' ') + sizeof(core_name) - 1;
3567 data = malloc(len, M_TEMP, M_WAITOK);
3568 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3570 if (!coredump_sanitise_path(fullpath))
3572 snprintf(data, len, "%s%s ", comm_name, fullpath);
3573 free(freepath, M_TEMP);
3575 if (vn_fullpath_global(td, vp, &fullpath, &freepath) != 0)
3577 if (!coredump_sanitise_path(fullpath))
3579 strlcat(data, core_name, len);
3580 strlcat(data, fullpath, len);
3581 devctl_notify("kernel", "signal", "coredump", data);
3583 error1 = vn_close(vp, FWRITE, cred, td);
3587 audit_proc_coredump(td, name, error);
3589 free(freepath, M_TEMP);
3596 * Nonexistent system call-- signal process (may want to handle it). Flag
3597 * error in case process won't see signal immediately (blocked or ignored).
3599 #ifndef _SYS_SYSPROTO_H_
3606 nosys(struct thread *td, struct nosys_args *args)
3613 tdsignal(td, SIGSYS);
3615 if (kern_lognosys == 1 || kern_lognosys == 3) {
3616 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3619 if (kern_lognosys == 2 || kern_lognosys == 3) {
3620 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3627 * Send a SIGIO or SIGURG signal to a process or process group using stored
3628 * credentials rather than those of the current process.
3631 pgsigio(struct sigio **sigiop, int sig, int checkctty)
3634 struct sigio *sigio;
3636 ksiginfo_init(&ksi);
3637 ksi.ksi_signo = sig;
3638 ksi.ksi_code = SI_KERNEL;
3642 if (sigio == NULL) {
3646 if (sigio->sio_pgid > 0) {
3647 PROC_LOCK(sigio->sio_proc);
3648 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3649 kern_psignal(sigio->sio_proc, sig);
3650 PROC_UNLOCK(sigio->sio_proc);
3651 } else if (sigio->sio_pgid < 0) {
3654 PGRP_LOCK(sigio->sio_pgrp);
3655 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3657 if (p->p_state == PRS_NORMAL &&
3658 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3659 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3660 kern_psignal(p, sig);
3663 PGRP_UNLOCK(sigio->sio_pgrp);
3669 filt_sigattach(struct knote *kn)
3671 struct proc *p = curproc;
3673 kn->kn_ptr.p_proc = p;
3674 kn->kn_flags |= EV_CLEAR; /* automatically set */
3676 knlist_add(p->p_klist, kn, 0);
3682 filt_sigdetach(struct knote *kn)
3684 struct proc *p = kn->kn_ptr.p_proc;
3686 knlist_remove(p->p_klist, kn, 0);
3690 * signal knotes are shared with proc knotes, so we apply a mask to
3691 * the hint in order to differentiate them from process hints. This
3692 * could be avoided by using a signal-specific knote list, but probably
3693 * isn't worth the trouble.
3696 filt_signal(struct knote *kn, long hint)
3699 if (hint & NOTE_SIGNAL) {
3700 hint &= ~NOTE_SIGNAL;
3702 if (kn->kn_id == hint)
3705 return (kn->kn_data != 0);
3713 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3714 refcount_init(&ps->ps_refcnt, 1);
3715 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3720 sigacts_free(struct sigacts *ps)
3723 if (refcount_release(&ps->ps_refcnt) == 0)
3725 mtx_destroy(&ps->ps_mtx);
3726 free(ps, M_SUBPROC);
3730 sigacts_hold(struct sigacts *ps)
3733 refcount_acquire(&ps->ps_refcnt);
3738 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3741 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3742 mtx_lock(&src->ps_mtx);
3743 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3744 mtx_unlock(&src->ps_mtx);
3748 sigacts_shared(struct sigacts *ps)
3751 return (ps->ps_refcnt > 1);