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
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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_compat.h"
43 #include "opt_ktrace.h"
45 #include <sys/param.h>
46 #include <sys/ctype.h>
47 #include <sys/systm.h>
48 #include <sys/signalvar.h>
49 #include <sys/vnode.h>
52 #include <sys/capsicum.h>
53 #include <sys/compressor.h>
54 #include <sys/condvar.h>
55 #include <sys/event.h>
56 #include <sys/fcntl.h>
57 #include <sys/imgact.h>
58 #include <sys/kernel.h>
60 #include <sys/ktrace.h>
62 #include <sys/malloc.h>
63 #include <sys/mutex.h>
64 #include <sys/refcount.h>
65 #include <sys/namei.h>
67 #include <sys/procdesc.h>
68 #include <sys/posix4.h>
69 #include <sys/pioctl.h>
70 #include <sys/racct.h>
71 #include <sys/resourcevar.h>
74 #include <sys/sleepqueue.h>
78 #include <sys/syscallsubr.h>
79 #include <sys/sysctl.h>
80 #include <sys/sysent.h>
81 #include <sys/syslog.h>
82 #include <sys/sysproto.h>
83 #include <sys/timers.h>
84 #include <sys/unistd.h>
87 #include <vm/vm_extern.h>
92 #include <machine/cpu.h>
94 #include <security/audit/audit.h>
96 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
98 SDT_PROVIDER_DECLARE(proc);
99 SDT_PROBE_DEFINE3(proc, , , signal__send,
100 "struct thread *", "struct proc *", "int");
101 SDT_PROBE_DEFINE2(proc, , , signal__clear,
102 "int", "ksiginfo_t *");
103 SDT_PROBE_DEFINE3(proc, , , signal__discard,
104 "struct thread *", "struct proc *", "int");
106 static int coredump(struct thread *);
107 static int killpg1(struct thread *td, int sig, int pgid, int all,
109 static int issignal(struct thread *td);
110 static int sigprop(int sig);
111 static void tdsigwakeup(struct thread *, int, sig_t, int);
112 static int sig_suspend_threads(struct thread *, struct proc *, int);
113 static int filt_sigattach(struct knote *kn);
114 static void filt_sigdetach(struct knote *kn);
115 static int filt_signal(struct knote *kn, long hint);
116 static struct thread *sigtd(struct proc *p, int sig, int prop);
117 static void sigqueue_start(void);
119 static uma_zone_t ksiginfo_zone = NULL;
120 struct filterops sig_filtops = {
122 .f_attach = filt_sigattach,
123 .f_detach = filt_sigdetach,
124 .f_event = filt_signal,
127 static int kern_logsigexit = 1;
128 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
130 "Log processes quitting on abnormal signals to syslog(3)");
132 static int kern_forcesigexit = 1;
133 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
134 &kern_forcesigexit, 0, "Force trap signal to be handled");
136 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
137 "POSIX real time signal");
139 static int max_pending_per_proc = 128;
140 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
141 &max_pending_per_proc, 0, "Max pending signals per proc");
143 static int preallocate_siginfo = 1024;
144 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
145 &preallocate_siginfo, 0, "Preallocated signal memory size");
147 static int signal_overflow = 0;
148 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
149 &signal_overflow, 0, "Number of signals overflew");
151 static int signal_alloc_fail = 0;
152 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
153 &signal_alloc_fail, 0, "signals failed to be allocated");
155 static int kern_lognosys = 0;
156 SYSCTL_INT(_kern, OID_AUTO, lognosys, CTLFLAG_RWTUN, &kern_lognosys, 0,
157 "Log invalid syscalls");
159 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
162 * Policy -- Can ucred cr1 send SIGIO to process cr2?
163 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
164 * in the right situations.
166 #define CANSIGIO(cr1, cr2) \
167 ((cr1)->cr_uid == 0 || \
168 (cr1)->cr_ruid == (cr2)->cr_ruid || \
169 (cr1)->cr_uid == (cr2)->cr_ruid || \
170 (cr1)->cr_ruid == (cr2)->cr_uid || \
171 (cr1)->cr_uid == (cr2)->cr_uid)
173 static int sugid_coredump;
174 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
175 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
177 static int capmode_coredump;
178 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
179 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
181 static int do_coredump = 1;
182 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
183 &do_coredump, 0, "Enable/Disable coredumps");
185 static int set_core_nodump_flag = 0;
186 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
187 0, "Enable setting the NODUMP flag on coredump files");
189 static int coredump_devctl = 0;
190 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
191 0, "Generate a devctl notification when processes coredump");
194 * Signal properties and actions.
195 * The array below categorizes the signals and their default actions
196 * according to the following properties:
198 #define SIGPROP_KILL 0x01 /* terminates process by default */
199 #define SIGPROP_CORE 0x02 /* ditto and coredumps */
200 #define SIGPROP_STOP 0x04 /* suspend process */
201 #define SIGPROP_TTYSTOP 0x08 /* ditto, from tty */
202 #define SIGPROP_IGNORE 0x10 /* ignore by default */
203 #define SIGPROP_CONT 0x20 /* continue if suspended */
204 #define SIGPROP_CANTMASK 0x40 /* non-maskable, catchable */
206 static int sigproptbl[NSIG] = {
207 [SIGHUP] = SIGPROP_KILL,
208 [SIGINT] = SIGPROP_KILL,
209 [SIGQUIT] = SIGPROP_KILL | SIGPROP_CORE,
210 [SIGILL] = SIGPROP_KILL | SIGPROP_CORE,
211 [SIGTRAP] = SIGPROP_KILL | SIGPROP_CORE,
212 [SIGABRT] = SIGPROP_KILL | SIGPROP_CORE,
213 [SIGEMT] = SIGPROP_KILL | SIGPROP_CORE,
214 [SIGFPE] = SIGPROP_KILL | SIGPROP_CORE,
215 [SIGKILL] = SIGPROP_KILL,
216 [SIGBUS] = SIGPROP_KILL | SIGPROP_CORE,
217 [SIGSEGV] = SIGPROP_KILL | SIGPROP_CORE,
218 [SIGSYS] = SIGPROP_KILL | SIGPROP_CORE,
219 [SIGPIPE] = SIGPROP_KILL,
220 [SIGALRM] = SIGPROP_KILL,
221 [SIGTERM] = SIGPROP_KILL,
222 [SIGURG] = SIGPROP_IGNORE,
223 [SIGSTOP] = SIGPROP_STOP,
224 [SIGTSTP] = SIGPROP_STOP | SIGPROP_TTYSTOP,
225 [SIGCONT] = SIGPROP_IGNORE | SIGPROP_CONT,
226 [SIGCHLD] = SIGPROP_IGNORE,
227 [SIGTTIN] = SIGPROP_STOP | SIGPROP_TTYSTOP,
228 [SIGTTOU] = SIGPROP_STOP | SIGPROP_TTYSTOP,
229 [SIGIO] = SIGPROP_IGNORE,
230 [SIGXCPU] = SIGPROP_KILL,
231 [SIGXFSZ] = SIGPROP_KILL,
232 [SIGVTALRM] = SIGPROP_KILL,
233 [SIGPROF] = SIGPROP_KILL,
234 [SIGWINCH] = SIGPROP_IGNORE,
235 [SIGINFO] = SIGPROP_IGNORE,
236 [SIGUSR1] = SIGPROP_KILL,
237 [SIGUSR2] = SIGPROP_KILL,
240 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
245 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
246 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
247 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
248 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
249 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
250 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
254 ksiginfo_alloc(int wait)
261 if (ksiginfo_zone != NULL)
262 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
267 ksiginfo_free(ksiginfo_t *ksi)
269 uma_zfree(ksiginfo_zone, ksi);
273 ksiginfo_tryfree(ksiginfo_t *ksi)
275 if (!(ksi->ksi_flags & KSI_EXT)) {
276 uma_zfree(ksiginfo_zone, ksi);
283 sigqueue_init(sigqueue_t *list, struct proc *p)
285 SIGEMPTYSET(list->sq_signals);
286 SIGEMPTYSET(list->sq_kill);
287 SIGEMPTYSET(list->sq_ptrace);
288 TAILQ_INIT(&list->sq_list);
290 list->sq_flags = SQ_INIT;
294 * Get a signal's ksiginfo.
296 * 0 - signal not found
297 * others - signal number
300 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
302 struct proc *p = sq->sq_proc;
303 struct ksiginfo *ksi, *next;
306 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
308 if (!SIGISMEMBER(sq->sq_signals, signo))
311 if (SIGISMEMBER(sq->sq_ptrace, signo)) {
313 SIGDELSET(sq->sq_ptrace, signo);
314 si->ksi_flags |= KSI_PTRACE;
316 if (SIGISMEMBER(sq->sq_kill, signo)) {
319 SIGDELSET(sq->sq_kill, signo);
322 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
323 if (ksi->ksi_signo == signo) {
325 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
326 ksi->ksi_sigq = NULL;
327 ksiginfo_copy(ksi, si);
328 if (ksiginfo_tryfree(ksi) && p != NULL)
337 SIGDELSET(sq->sq_signals, signo);
338 si->ksi_signo = signo;
343 sigqueue_take(ksiginfo_t *ksi)
349 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
353 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
354 ksi->ksi_sigq = NULL;
355 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
358 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
359 kp = TAILQ_NEXT(kp, ksi_link)) {
360 if (kp->ksi_signo == ksi->ksi_signo)
363 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) &&
364 !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo))
365 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
369 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
371 struct proc *p = sq->sq_proc;
372 struct ksiginfo *ksi;
375 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
378 * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path
381 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
382 SIGADDSET(sq->sq_kill, signo);
386 /* directly insert the ksi, don't copy it */
387 if (si->ksi_flags & KSI_INS) {
388 if (si->ksi_flags & KSI_HEAD)
389 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
391 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
396 if (__predict_false(ksiginfo_zone == NULL)) {
397 SIGADDSET(sq->sq_kill, signo);
401 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
404 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
410 ksiginfo_copy(si, ksi);
411 ksi->ksi_signo = signo;
412 if (si->ksi_flags & KSI_HEAD)
413 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
415 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
420 if ((si->ksi_flags & KSI_PTRACE) != 0) {
421 SIGADDSET(sq->sq_ptrace, signo);
424 } else if ((si->ksi_flags & KSI_TRAP) != 0 ||
425 (si->ksi_flags & KSI_SIGQ) == 0) {
426 SIGADDSET(sq->sq_kill, signo);
434 SIGADDSET(sq->sq_signals, signo);
439 sigqueue_flush(sigqueue_t *sq)
441 struct proc *p = sq->sq_proc;
444 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
447 PROC_LOCK_ASSERT(p, MA_OWNED);
449 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
450 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
451 ksi->ksi_sigq = NULL;
452 if (ksiginfo_tryfree(ksi) && p != NULL)
456 SIGEMPTYSET(sq->sq_signals);
457 SIGEMPTYSET(sq->sq_kill);
458 SIGEMPTYSET(sq->sq_ptrace);
462 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
465 struct proc *p1, *p2;
466 ksiginfo_t *ksi, *next;
468 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
469 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
472 /* Move siginfo to target list */
473 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
474 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
475 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
478 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
485 /* Move pending bits to target list */
487 SIGSETAND(tmp, *set);
488 SIGSETOR(dst->sq_kill, tmp);
489 SIGSETNAND(src->sq_kill, tmp);
491 tmp = src->sq_ptrace;
492 SIGSETAND(tmp, *set);
493 SIGSETOR(dst->sq_ptrace, tmp);
494 SIGSETNAND(src->sq_ptrace, tmp);
496 tmp = src->sq_signals;
497 SIGSETAND(tmp, *set);
498 SIGSETOR(dst->sq_signals, tmp);
499 SIGSETNAND(src->sq_signals, tmp);
504 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
509 SIGADDSET(set, signo);
510 sigqueue_move_set(src, dst, &set);
515 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
517 struct proc *p = sq->sq_proc;
518 ksiginfo_t *ksi, *next;
520 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
522 /* Remove siginfo queue */
523 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
524 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
525 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
526 ksi->ksi_sigq = NULL;
527 if (ksiginfo_tryfree(ksi) && p != NULL)
531 SIGSETNAND(sq->sq_kill, *set);
532 SIGSETNAND(sq->sq_ptrace, *set);
533 SIGSETNAND(sq->sq_signals, *set);
537 sigqueue_delete(sigqueue_t *sq, int signo)
542 SIGADDSET(set, signo);
543 sigqueue_delete_set(sq, &set);
546 /* Remove a set of signals for a process */
548 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
553 PROC_LOCK_ASSERT(p, MA_OWNED);
555 sigqueue_init(&worklist, NULL);
556 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
558 FOREACH_THREAD_IN_PROC(p, td0)
559 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
561 sigqueue_flush(&worklist);
565 sigqueue_delete_proc(struct proc *p, int signo)
570 SIGADDSET(set, signo);
571 sigqueue_delete_set_proc(p, &set);
575 sigqueue_delete_stopmask_proc(struct proc *p)
580 SIGADDSET(set, SIGSTOP);
581 SIGADDSET(set, SIGTSTP);
582 SIGADDSET(set, SIGTTIN);
583 SIGADDSET(set, SIGTTOU);
584 sigqueue_delete_set_proc(p, &set);
588 * Determine signal that should be delivered to thread td, the current
589 * thread, 0 if none. If there is a pending stop signal with default
590 * action, the process stops in issignal().
593 cursig(struct thread *td)
595 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
596 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
597 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
598 return (SIGPENDING(td) ? issignal(td) : 0);
602 * Arrange for ast() to handle unmasked pending signals on return to user
603 * mode. This must be called whenever a signal is added to td_sigqueue or
604 * unmasked in td_sigmask.
607 signotify(struct thread *td)
613 PROC_LOCK_ASSERT(p, MA_OWNED);
615 if (SIGPENDING(td)) {
617 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
623 sigonstack(size_t sp)
625 struct thread *td = curthread;
627 return ((td->td_pflags & TDP_ALTSTACK) ?
628 #if defined(COMPAT_43)
629 ((td->td_sigstk.ss_size == 0) ?
630 (td->td_sigstk.ss_flags & SS_ONSTACK) :
631 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
633 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
642 if (sig > 0 && sig < nitems(sigproptbl))
643 return (sigproptbl[sig]);
648 sig_ffs(sigset_t *set)
652 for (i = 0; i < _SIG_WORDS; i++)
654 return (ffs(set->__bits[i]) + (i * 32));
659 sigact_flag_test(const struct sigaction *act, int flag)
663 * SA_SIGINFO is reset when signal disposition is set to
664 * ignore or default. Other flags are kept according to user
667 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
668 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
669 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
679 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
680 struct sigaction *oact, int flags)
683 struct proc *p = td->td_proc;
685 if (!_SIG_VALID(sig))
687 if (act != NULL && act->sa_handler != SIG_DFL &&
688 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
689 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
690 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
695 mtx_lock(&ps->ps_mtx);
697 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
699 if (SIGISMEMBER(ps->ps_sigonstack, sig))
700 oact->sa_flags |= SA_ONSTACK;
701 if (!SIGISMEMBER(ps->ps_sigintr, sig))
702 oact->sa_flags |= SA_RESTART;
703 if (SIGISMEMBER(ps->ps_sigreset, sig))
704 oact->sa_flags |= SA_RESETHAND;
705 if (SIGISMEMBER(ps->ps_signodefer, sig))
706 oact->sa_flags |= SA_NODEFER;
707 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
708 oact->sa_flags |= SA_SIGINFO;
710 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
712 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
713 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
714 oact->sa_flags |= SA_NOCLDSTOP;
715 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
716 oact->sa_flags |= SA_NOCLDWAIT;
719 if ((sig == SIGKILL || sig == SIGSTOP) &&
720 act->sa_handler != SIG_DFL) {
721 mtx_unlock(&ps->ps_mtx);
727 * Change setting atomically.
730 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
731 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
732 if (sigact_flag_test(act, SA_SIGINFO)) {
733 ps->ps_sigact[_SIG_IDX(sig)] =
734 (__sighandler_t *)act->sa_sigaction;
735 SIGADDSET(ps->ps_siginfo, sig);
737 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
738 SIGDELSET(ps->ps_siginfo, sig);
740 if (!sigact_flag_test(act, SA_RESTART))
741 SIGADDSET(ps->ps_sigintr, sig);
743 SIGDELSET(ps->ps_sigintr, sig);
744 if (sigact_flag_test(act, SA_ONSTACK))
745 SIGADDSET(ps->ps_sigonstack, sig);
747 SIGDELSET(ps->ps_sigonstack, sig);
748 if (sigact_flag_test(act, SA_RESETHAND))
749 SIGADDSET(ps->ps_sigreset, sig);
751 SIGDELSET(ps->ps_sigreset, sig);
752 if (sigact_flag_test(act, SA_NODEFER))
753 SIGADDSET(ps->ps_signodefer, sig);
755 SIGDELSET(ps->ps_signodefer, sig);
756 if (sig == SIGCHLD) {
757 if (act->sa_flags & SA_NOCLDSTOP)
758 ps->ps_flag |= PS_NOCLDSTOP;
760 ps->ps_flag &= ~PS_NOCLDSTOP;
761 if (act->sa_flags & SA_NOCLDWAIT) {
763 * Paranoia: since SA_NOCLDWAIT is implemented
764 * by reparenting the dying child to PID 1 (and
765 * trust it to reap the zombie), PID 1 itself
766 * is forbidden to set SA_NOCLDWAIT.
769 ps->ps_flag &= ~PS_NOCLDWAIT;
771 ps->ps_flag |= PS_NOCLDWAIT;
773 ps->ps_flag &= ~PS_NOCLDWAIT;
774 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
775 ps->ps_flag |= PS_CLDSIGIGN;
777 ps->ps_flag &= ~PS_CLDSIGIGN;
780 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
781 * and for signals set to SIG_DFL where the default is to
782 * ignore. However, don't put SIGCONT in ps_sigignore, as we
783 * have to restart the process.
785 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
786 (sigprop(sig) & SIGPROP_IGNORE &&
787 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
788 /* never to be seen again */
789 sigqueue_delete_proc(p, sig);
791 /* easier in psignal */
792 SIGADDSET(ps->ps_sigignore, sig);
793 SIGDELSET(ps->ps_sigcatch, sig);
795 SIGDELSET(ps->ps_sigignore, sig);
796 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
797 SIGDELSET(ps->ps_sigcatch, sig);
799 SIGADDSET(ps->ps_sigcatch, sig);
801 #ifdef COMPAT_FREEBSD4
802 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
803 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
804 (flags & KSA_FREEBSD4) == 0)
805 SIGDELSET(ps->ps_freebsd4, sig);
807 SIGADDSET(ps->ps_freebsd4, sig);
810 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
811 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
812 (flags & KSA_OSIGSET) == 0)
813 SIGDELSET(ps->ps_osigset, sig);
815 SIGADDSET(ps->ps_osigset, sig);
818 mtx_unlock(&ps->ps_mtx);
823 #ifndef _SYS_SYSPROTO_H_
824 struct sigaction_args {
826 struct sigaction *act;
827 struct sigaction *oact;
831 sys_sigaction(struct thread *td, struct sigaction_args *uap)
833 struct sigaction act, oact;
834 struct sigaction *actp, *oactp;
837 actp = (uap->act != NULL) ? &act : NULL;
838 oactp = (uap->oact != NULL) ? &oact : NULL;
840 error = copyin(uap->act, actp, sizeof(act));
844 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
846 error = copyout(oactp, uap->oact, sizeof(oact));
850 #ifdef COMPAT_FREEBSD4
851 #ifndef _SYS_SYSPROTO_H_
852 struct freebsd4_sigaction_args {
854 struct sigaction *act;
855 struct sigaction *oact;
859 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
861 struct sigaction act, oact;
862 struct sigaction *actp, *oactp;
866 actp = (uap->act != NULL) ? &act : NULL;
867 oactp = (uap->oact != NULL) ? &oact : NULL;
869 error = copyin(uap->act, actp, sizeof(act));
873 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
875 error = copyout(oactp, uap->oact, sizeof(oact));
878 #endif /* COMAPT_FREEBSD4 */
880 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
881 #ifndef _SYS_SYSPROTO_H_
882 struct osigaction_args {
884 struct osigaction *nsa;
885 struct osigaction *osa;
889 osigaction(struct thread *td, struct osigaction_args *uap)
891 struct osigaction sa;
892 struct sigaction nsa, osa;
893 struct sigaction *nsap, *osap;
896 if (uap->signum <= 0 || uap->signum >= ONSIG)
899 nsap = (uap->nsa != NULL) ? &nsa : NULL;
900 osap = (uap->osa != NULL) ? &osa : NULL;
903 error = copyin(uap->nsa, &sa, sizeof(sa));
906 nsap->sa_handler = sa.sa_handler;
907 nsap->sa_flags = sa.sa_flags;
908 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
910 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
911 if (osap && !error) {
912 sa.sa_handler = osap->sa_handler;
913 sa.sa_flags = osap->sa_flags;
914 SIG2OSIG(osap->sa_mask, sa.sa_mask);
915 error = copyout(&sa, uap->osa, sizeof(sa));
920 #if !defined(__i386__)
921 /* Avoid replicating the same stub everywhere */
923 osigreturn(struct thread *td, struct osigreturn_args *uap)
926 return (nosys(td, (struct nosys_args *)uap));
929 #endif /* COMPAT_43 */
932 * Initialize signal state for process 0;
933 * set to ignore signals that are ignored by default.
936 siginit(struct proc *p)
943 mtx_lock(&ps->ps_mtx);
944 for (i = 1; i <= NSIG; i++) {
945 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
946 SIGADDSET(ps->ps_sigignore, i);
949 mtx_unlock(&ps->ps_mtx);
954 * Reset specified signal to the default disposition.
957 sigdflt(struct sigacts *ps, int sig)
960 mtx_assert(&ps->ps_mtx, MA_OWNED);
961 SIGDELSET(ps->ps_sigcatch, sig);
962 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
963 SIGADDSET(ps->ps_sigignore, sig);
964 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
965 SIGDELSET(ps->ps_siginfo, sig);
969 * Reset signals for an exec of the specified process.
972 execsigs(struct proc *p)
980 * Reset caught signals. Held signals remain held
981 * through td_sigmask (unless they were caught,
982 * and are now ignored by default).
984 PROC_LOCK_ASSERT(p, MA_OWNED);
986 mtx_lock(&ps->ps_mtx);
987 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
988 sig = sig_ffs(&ps->ps_sigcatch);
990 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
991 sigqueue_delete_proc(p, sig);
995 * As CloudABI processes cannot modify signal handlers, fully
996 * reset all signals to their default behavior. Do ignore
997 * SIGPIPE, as it would otherwise be impossible to recover from
998 * writes to broken pipes and sockets.
1000 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
1001 osigignore = ps->ps_sigignore;
1002 while (SIGNOTEMPTY(osigignore)) {
1003 sig = sig_ffs(&osigignore);
1004 SIGDELSET(osigignore, sig);
1008 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1012 * Reset stack state to the user stack.
1013 * Clear set of signals caught on the signal stack.
1016 MPASS(td->td_proc == p);
1017 td->td_sigstk.ss_flags = SS_DISABLE;
1018 td->td_sigstk.ss_size = 0;
1019 td->td_sigstk.ss_sp = 0;
1020 td->td_pflags &= ~TDP_ALTSTACK;
1022 * Reset no zombies if child dies flag as Solaris does.
1024 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1025 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1026 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1027 mtx_unlock(&ps->ps_mtx);
1031 * kern_sigprocmask()
1033 * Manipulate signal mask.
1036 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1039 sigset_t new_block, oset1;
1044 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1045 PROC_LOCK_ASSERT(p, MA_OWNED);
1048 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1049 ? MA_OWNED : MA_NOTOWNED);
1051 *oset = td->td_sigmask;
1058 oset1 = td->td_sigmask;
1059 SIGSETOR(td->td_sigmask, *set);
1060 new_block = td->td_sigmask;
1061 SIGSETNAND(new_block, oset1);
1064 SIGSETNAND(td->td_sigmask, *set);
1069 oset1 = td->td_sigmask;
1070 if (flags & SIGPROCMASK_OLD)
1071 SIGSETLO(td->td_sigmask, *set);
1073 td->td_sigmask = *set;
1074 new_block = td->td_sigmask;
1075 SIGSETNAND(new_block, oset1);
1084 * The new_block set contains signals that were not previously
1085 * blocked, but are blocked now.
1087 * In case we block any signal that was not previously blocked
1088 * for td, and process has the signal pending, try to schedule
1089 * signal delivery to some thread that does not block the
1090 * signal, possibly waking it up.
1092 if (p->p_numthreads != 1)
1093 reschedule_signals(p, new_block, flags);
1097 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1102 #ifndef _SYS_SYSPROTO_H_
1103 struct sigprocmask_args {
1105 const sigset_t *set;
1110 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1113 sigset_t *setp, *osetp;
1116 setp = (uap->set != NULL) ? &set : NULL;
1117 osetp = (uap->oset != NULL) ? &oset : NULL;
1119 error = copyin(uap->set, setp, sizeof(set));
1123 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1124 if (osetp && !error) {
1125 error = copyout(osetp, uap->oset, sizeof(oset));
1130 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1131 #ifndef _SYS_SYSPROTO_H_
1132 struct osigprocmask_args {
1138 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1143 OSIG2SIG(uap->mask, set);
1144 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1145 SIG2OSIG(oset, td->td_retval[0]);
1148 #endif /* COMPAT_43 */
1151 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1157 error = copyin(uap->set, &set, sizeof(set));
1159 td->td_retval[0] = error;
1163 error = kern_sigtimedwait(td, set, &ksi, NULL);
1165 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1167 if (error == ERESTART)
1169 td->td_retval[0] = error;
1173 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1174 td->td_retval[0] = error;
1179 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1182 struct timespec *timeout;
1188 error = copyin(uap->timeout, &ts, sizeof(ts));
1196 error = copyin(uap->set, &set, sizeof(set));
1200 error = kern_sigtimedwait(td, set, &ksi, timeout);
1205 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1208 td->td_retval[0] = ksi.ksi_signo;
1213 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1219 error = copyin(uap->set, &set, sizeof(set));
1223 error = kern_sigtimedwait(td, set, &ksi, NULL);
1228 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1231 td->td_retval[0] = ksi.ksi_signo;
1236 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1240 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1244 thr->td_si.si_signo = 0;
1249 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1250 struct timespec *timeout)
1253 sigset_t saved_mask, new_block;
1255 int error, sig, timo, timevalid = 0;
1256 struct timespec rts, ets, ts;
1264 if (timeout != NULL) {
1265 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1267 getnanouptime(&rts);
1269 timespecadd(&ets, timeout);
1273 /* Some signals can not be waited for. */
1274 SIG_CANTMASK(waitset);
1277 saved_mask = td->td_sigmask;
1278 SIGSETNAND(td->td_sigmask, waitset);
1280 mtx_lock(&ps->ps_mtx);
1282 mtx_unlock(&ps->ps_mtx);
1283 KASSERT(sig >= 0, ("sig %d", sig));
1284 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1285 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1286 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1296 * POSIX says this must be checked after looking for pending
1299 if (timeout != NULL) {
1304 getnanouptime(&rts);
1305 if (timespeccmp(&rts, &ets, >=)) {
1310 timespecsub(&ts, &rts);
1311 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1317 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1319 if (timeout != NULL) {
1320 if (error == ERESTART) {
1321 /* Timeout can not be restarted. */
1323 } else if (error == EAGAIN) {
1324 /* We will calculate timeout by ourself. */
1330 new_block = saved_mask;
1331 SIGSETNAND(new_block, td->td_sigmask);
1332 td->td_sigmask = saved_mask;
1334 * Fewer signals can be delivered to us, reschedule signal
1337 if (p->p_numthreads != 1)
1338 reschedule_signals(p, new_block, 0);
1341 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1343 if (ksi->ksi_code == SI_TIMER)
1344 itimer_accept(p, ksi->ksi_timerid, ksi);
1347 if (KTRPOINT(td, KTR_PSIG)) {
1350 mtx_lock(&ps->ps_mtx);
1351 action = ps->ps_sigact[_SIG_IDX(sig)];
1352 mtx_unlock(&ps->ps_mtx);
1353 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1356 if (sig == SIGKILL) {
1357 proc_td_siginfo_capture(td, &ksi->ksi_info);
1365 #ifndef _SYS_SYSPROTO_H_
1366 struct sigpending_args {
1371 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1373 struct proc *p = td->td_proc;
1377 pending = p->p_sigqueue.sq_signals;
1378 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1380 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1383 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1384 #ifndef _SYS_SYSPROTO_H_
1385 struct osigpending_args {
1390 osigpending(struct thread *td, struct osigpending_args *uap)
1392 struct proc *p = td->td_proc;
1396 pending = p->p_sigqueue.sq_signals;
1397 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1399 SIG2OSIG(pending, td->td_retval[0]);
1402 #endif /* COMPAT_43 */
1404 #if defined(COMPAT_43)
1406 * Generalized interface signal handler, 4.3-compatible.
1408 #ifndef _SYS_SYSPROTO_H_
1409 struct osigvec_args {
1417 osigvec(struct thread *td, struct osigvec_args *uap)
1420 struct sigaction nsa, osa;
1421 struct sigaction *nsap, *osap;
1424 if (uap->signum <= 0 || uap->signum >= ONSIG)
1426 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1427 osap = (uap->osv != NULL) ? &osa : NULL;
1429 error = copyin(uap->nsv, &vec, sizeof(vec));
1432 nsap->sa_handler = vec.sv_handler;
1433 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1434 nsap->sa_flags = vec.sv_flags;
1435 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1437 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1438 if (osap && !error) {
1439 vec.sv_handler = osap->sa_handler;
1440 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1441 vec.sv_flags = osap->sa_flags;
1442 vec.sv_flags &= ~SA_NOCLDWAIT;
1443 vec.sv_flags ^= SA_RESTART;
1444 error = copyout(&vec, uap->osv, sizeof(vec));
1449 #ifndef _SYS_SYSPROTO_H_
1450 struct osigblock_args {
1455 osigblock(struct thread *td, struct osigblock_args *uap)
1459 OSIG2SIG(uap->mask, set);
1460 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1461 SIG2OSIG(oset, td->td_retval[0]);
1465 #ifndef _SYS_SYSPROTO_H_
1466 struct osigsetmask_args {
1471 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1475 OSIG2SIG(uap->mask, set);
1476 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1477 SIG2OSIG(oset, td->td_retval[0]);
1480 #endif /* COMPAT_43 */
1483 * Suspend calling thread until signal, providing mask to be set in the
1486 #ifndef _SYS_SYSPROTO_H_
1487 struct sigsuspend_args {
1488 const sigset_t *sigmask;
1493 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1498 error = copyin(uap->sigmask, &mask, sizeof(mask));
1501 return (kern_sigsuspend(td, mask));
1505 kern_sigsuspend(struct thread *td, sigset_t mask)
1507 struct proc *p = td->td_proc;
1511 * When returning from sigsuspend, we want
1512 * the old mask to be restored after the
1513 * signal handler has finished. Thus, we
1514 * save it here and mark the sigacts structure
1518 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1519 SIGPROCMASK_PROC_LOCKED);
1520 td->td_pflags |= TDP_OLDMASK;
1523 * Process signals now. Otherwise, we can get spurious wakeup
1524 * due to signal entered process queue, but delivered to other
1525 * thread. But sigsuspend should return only on signal
1528 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1529 for (has_sig = 0; !has_sig;) {
1530 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1533 thread_suspend_check(0);
1534 mtx_lock(&p->p_sigacts->ps_mtx);
1535 while ((sig = cursig(td)) != 0) {
1536 KASSERT(sig >= 0, ("sig %d", sig));
1537 has_sig += postsig(sig);
1539 mtx_unlock(&p->p_sigacts->ps_mtx);
1542 td->td_errno = EINTR;
1543 td->td_pflags |= TDP_NERRNO;
1544 return (EJUSTRETURN);
1547 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1549 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1550 * convention: libc stub passes mask, not pointer, to save a copyin.
1552 #ifndef _SYS_SYSPROTO_H_
1553 struct osigsuspend_args {
1559 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1563 OSIG2SIG(uap->mask, mask);
1564 return (kern_sigsuspend(td, mask));
1566 #endif /* COMPAT_43 */
1568 #if defined(COMPAT_43)
1569 #ifndef _SYS_SYSPROTO_H_
1570 struct osigstack_args {
1571 struct sigstack *nss;
1572 struct sigstack *oss;
1577 osigstack(struct thread *td, struct osigstack_args *uap)
1579 struct sigstack nss, oss;
1582 if (uap->nss != NULL) {
1583 error = copyin(uap->nss, &nss, sizeof(nss));
1587 oss.ss_sp = td->td_sigstk.ss_sp;
1588 oss.ss_onstack = sigonstack(cpu_getstack(td));
1589 if (uap->nss != NULL) {
1590 td->td_sigstk.ss_sp = nss.ss_sp;
1591 td->td_sigstk.ss_size = 0;
1592 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1593 td->td_pflags |= TDP_ALTSTACK;
1595 if (uap->oss != NULL)
1596 error = copyout(&oss, uap->oss, sizeof(oss));
1600 #endif /* COMPAT_43 */
1602 #ifndef _SYS_SYSPROTO_H_
1603 struct sigaltstack_args {
1610 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1615 if (uap->ss != NULL) {
1616 error = copyin(uap->ss, &ss, sizeof(ss));
1620 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1621 (uap->oss != NULL) ? &oss : NULL);
1624 if (uap->oss != NULL)
1625 error = copyout(&oss, uap->oss, sizeof(stack_t));
1630 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1632 struct proc *p = td->td_proc;
1635 oonstack = sigonstack(cpu_getstack(td));
1638 *oss = td->td_sigstk;
1639 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1640 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1646 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1648 if (!(ss->ss_flags & SS_DISABLE)) {
1649 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1652 td->td_sigstk = *ss;
1653 td->td_pflags |= TDP_ALTSTACK;
1655 td->td_pflags &= ~TDP_ALTSTACK;
1662 * Common code for kill process group/broadcast kill.
1663 * cp is calling process.
1666 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1678 sx_slock(&allproc_lock);
1679 FOREACH_PROC_IN_SYSTEM(p) {
1681 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1682 p == td->td_proc || p->p_state == PRS_NEW) {
1686 err = p_cansignal(td, p, sig);
1689 pksignal(p, sig, ksi);
1692 else if (ret == ESRCH)
1696 sx_sunlock(&allproc_lock);
1698 sx_slock(&proctree_lock);
1701 * zero pgid means send to my process group.
1703 pgrp = td->td_proc->p_pgrp;
1706 pgrp = pgfind(pgid);
1708 sx_sunlock(&proctree_lock);
1712 sx_sunlock(&proctree_lock);
1713 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1715 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1716 p->p_state == PRS_NEW) {
1720 err = p_cansignal(td, p, sig);
1723 pksignal(p, sig, ksi);
1726 else if (ret == ESRCH)
1735 #ifndef _SYS_SYSPROTO_H_
1743 sys_kill(struct thread *td, struct kill_args *uap)
1750 * A process in capability mode can send signals only to himself.
1751 * The main rationale behind this is that abort(3) is implemented as
1752 * kill(getpid(), SIGABRT).
1754 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1757 AUDIT_ARG_SIGNUM(uap->signum);
1758 AUDIT_ARG_PID(uap->pid);
1759 if ((u_int)uap->signum > _SIG_MAXSIG)
1762 ksiginfo_init(&ksi);
1763 ksi.ksi_signo = uap->signum;
1764 ksi.ksi_code = SI_USER;
1765 ksi.ksi_pid = td->td_proc->p_pid;
1766 ksi.ksi_uid = td->td_ucred->cr_ruid;
1769 /* kill single process */
1770 if ((p = pfind_any(uap->pid)) == NULL)
1772 AUDIT_ARG_PROCESS(p);
1773 error = p_cansignal(td, p, uap->signum);
1774 if (error == 0 && uap->signum)
1775 pksignal(p, uap->signum, &ksi);
1780 case -1: /* broadcast signal */
1781 return (killpg1(td, uap->signum, 0, 1, &ksi));
1782 case 0: /* signal own process group */
1783 return (killpg1(td, uap->signum, 0, 0, &ksi));
1784 default: /* negative explicit process group */
1785 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1791 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1794 cap_rights_t rights;
1797 AUDIT_ARG_SIGNUM(uap->signum);
1798 AUDIT_ARG_FD(uap->fd);
1799 if ((u_int)uap->signum > _SIG_MAXSIG)
1802 error = procdesc_find(td, uap->fd,
1803 cap_rights_init(&rights, CAP_PDKILL), &p);
1806 AUDIT_ARG_PROCESS(p);
1807 error = p_cansignal(td, p, uap->signum);
1808 if (error == 0 && uap->signum)
1809 kern_psignal(p, uap->signum);
1814 #if defined(COMPAT_43)
1815 #ifndef _SYS_SYSPROTO_H_
1816 struct okillpg_args {
1823 okillpg(struct thread *td, struct okillpg_args *uap)
1827 AUDIT_ARG_SIGNUM(uap->signum);
1828 AUDIT_ARG_PID(uap->pgid);
1829 if ((u_int)uap->signum > _SIG_MAXSIG)
1832 ksiginfo_init(&ksi);
1833 ksi.ksi_signo = uap->signum;
1834 ksi.ksi_code = SI_USER;
1835 ksi.ksi_pid = td->td_proc->p_pid;
1836 ksi.ksi_uid = td->td_ucred->cr_ruid;
1837 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1839 #endif /* COMPAT_43 */
1841 #ifndef _SYS_SYSPROTO_H_
1842 struct sigqueue_args {
1845 /* union sigval */ void *value;
1849 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1853 sv.sival_ptr = uap->value;
1855 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1859 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1865 if ((u_int)signum > _SIG_MAXSIG)
1869 * Specification says sigqueue can only send signal to
1875 if ((p = pfind_any(pid)) == NULL)
1877 error = p_cansignal(td, p, signum);
1878 if (error == 0 && signum != 0) {
1879 ksiginfo_init(&ksi);
1880 ksi.ksi_flags = KSI_SIGQ;
1881 ksi.ksi_signo = signum;
1882 ksi.ksi_code = SI_QUEUE;
1883 ksi.ksi_pid = td->td_proc->p_pid;
1884 ksi.ksi_uid = td->td_ucred->cr_ruid;
1885 ksi.ksi_value = *value;
1886 error = pksignal(p, ksi.ksi_signo, &ksi);
1893 * Send a signal to a process group.
1896 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1901 sx_slock(&proctree_lock);
1902 pgrp = pgfind(pgid);
1903 sx_sunlock(&proctree_lock);
1905 pgsignal(pgrp, sig, 0, ksi);
1912 * Send a signal to a process group. If checktty is 1,
1913 * limit to members which have a controlling terminal.
1916 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1921 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1922 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1924 if (p->p_state == PRS_NORMAL &&
1925 (checkctty == 0 || p->p_flag & P_CONTROLT))
1926 pksignal(p, sig, ksi);
1934 * Recalculate the signal mask and reset the signal disposition after
1935 * usermode frame for delivery is formed. Should be called after
1936 * mach-specific routine, because sysent->sv_sendsig() needs correct
1937 * ps_siginfo and signal mask.
1940 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1944 mtx_assert(&ps->ps_mtx, MA_OWNED);
1945 td->td_ru.ru_nsignals++;
1946 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1947 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1948 SIGADDSET(mask, sig);
1949 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1950 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1951 if (SIGISMEMBER(ps->ps_sigreset, sig))
1957 * Send a signal caused by a trap to the current thread. If it will be
1958 * caught immediately, deliver it with correct code. Otherwise, post it
1962 trapsignal(struct thread *td, ksiginfo_t *ksi)
1970 sig = ksi->ksi_signo;
1971 code = ksi->ksi_code;
1972 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1976 mtx_lock(&ps->ps_mtx);
1977 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1978 !SIGISMEMBER(td->td_sigmask, sig)) {
1980 if (KTRPOINT(curthread, KTR_PSIG))
1981 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1982 &td->td_sigmask, code);
1984 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1985 ksi, &td->td_sigmask);
1986 postsig_done(sig, td, ps);
1987 mtx_unlock(&ps->ps_mtx);
1990 * Avoid a possible infinite loop if the thread
1991 * masking the signal or process is ignoring the
1994 if (kern_forcesigexit &&
1995 (SIGISMEMBER(td->td_sigmask, sig) ||
1996 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1997 SIGDELSET(td->td_sigmask, sig);
1998 SIGDELSET(ps->ps_sigcatch, sig);
1999 SIGDELSET(ps->ps_sigignore, sig);
2000 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2002 mtx_unlock(&ps->ps_mtx);
2003 p->p_code = code; /* XXX for core dump/debugger */
2004 p->p_sig = sig; /* XXX to verify code */
2005 tdsendsignal(p, td, sig, ksi);
2010 static struct thread *
2011 sigtd(struct proc *p, int sig, int prop)
2013 struct thread *td, *signal_td;
2015 PROC_LOCK_ASSERT(p, MA_OWNED);
2018 * Check if current thread can handle the signal without
2019 * switching context to another thread.
2021 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
2024 FOREACH_THREAD_IN_PROC(p, td) {
2025 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2030 if (signal_td == NULL)
2031 signal_td = FIRST_THREAD_IN_PROC(p);
2036 * Send the signal to the process. If the signal has an action, the action
2037 * is usually performed by the target process rather than the caller; we add
2038 * the signal to the set of pending signals for the process.
2041 * o When a stop signal is sent to a sleeping process that takes the
2042 * default action, the process is stopped without awakening it.
2043 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2044 * regardless of the signal action (eg, blocked or ignored).
2046 * Other ignored signals are discarded immediately.
2048 * NB: This function may be entered from the debugger via the "kill" DDB
2049 * command. There is little that can be done to mitigate the possibly messy
2050 * side effects of this unwise possibility.
2053 kern_psignal(struct proc *p, int sig)
2057 ksiginfo_init(&ksi);
2058 ksi.ksi_signo = sig;
2059 ksi.ksi_code = SI_KERNEL;
2060 (void) tdsendsignal(p, NULL, sig, &ksi);
2064 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2067 return (tdsendsignal(p, NULL, sig, ksi));
2070 /* Utility function for finding a thread to send signal event to. */
2072 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2076 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2077 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2089 tdsignal(struct thread *td, int sig)
2093 ksiginfo_init(&ksi);
2094 ksi.ksi_signo = sig;
2095 ksi.ksi_code = SI_KERNEL;
2096 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2100 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2103 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2107 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2110 sigqueue_t *sigqueue;
2117 MPASS(td == NULL || p == td->td_proc);
2118 PROC_LOCK_ASSERT(p, MA_OWNED);
2120 if (!_SIG_VALID(sig))
2121 panic("%s(): invalid signal %d", __func__, sig);
2123 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2126 * IEEE Std 1003.1-2001: return success when killing a zombie.
2128 if (p->p_state == PRS_ZOMBIE) {
2129 if (ksi && (ksi->ksi_flags & KSI_INS))
2130 ksiginfo_tryfree(ksi);
2135 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2136 prop = sigprop(sig);
2139 td = sigtd(p, sig, prop);
2140 sigqueue = &p->p_sigqueue;
2142 sigqueue = &td->td_sigqueue;
2144 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2147 * If the signal is being ignored,
2148 * then we forget about it immediately.
2149 * (Note: we don't set SIGCONT in ps_sigignore,
2150 * and if it is set to SIG_IGN,
2151 * action will be SIG_DFL here.)
2153 mtx_lock(&ps->ps_mtx);
2154 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2155 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2157 mtx_unlock(&ps->ps_mtx);
2158 if (ksi && (ksi->ksi_flags & KSI_INS))
2159 ksiginfo_tryfree(ksi);
2162 if (SIGISMEMBER(td->td_sigmask, sig))
2164 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2168 if (SIGISMEMBER(ps->ps_sigintr, sig))
2172 mtx_unlock(&ps->ps_mtx);
2174 if (prop & SIGPROP_CONT)
2175 sigqueue_delete_stopmask_proc(p);
2176 else if (prop & SIGPROP_STOP) {
2178 * If sending a tty stop signal to a member of an orphaned
2179 * process group, discard the signal here if the action
2180 * is default; don't stop the process below if sleeping,
2181 * and don't clear any pending SIGCONT.
2183 if ((prop & SIGPROP_TTYSTOP) &&
2184 (p->p_pgrp->pg_jobc == 0) &&
2185 (action == SIG_DFL)) {
2186 if (ksi && (ksi->ksi_flags & KSI_INS))
2187 ksiginfo_tryfree(ksi);
2190 sigqueue_delete_proc(p, SIGCONT);
2191 if (p->p_flag & P_CONTINUED) {
2192 p->p_flag &= ~P_CONTINUED;
2193 PROC_LOCK(p->p_pptr);
2194 sigqueue_take(p->p_ksi);
2195 PROC_UNLOCK(p->p_pptr);
2199 ret = sigqueue_add(sigqueue, sig, ksi);
2204 * Defer further processing for signals which are held,
2205 * except that stopped processes must be continued by SIGCONT.
2207 if (action == SIG_HOLD &&
2208 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2211 /* SIGKILL: Remove procfs STOPEVENTs. */
2212 if (sig == SIGKILL) {
2213 /* from procfs_ioctl.c: PIOCBIC */
2215 /* from procfs_ioctl.c: PIOCCONT */
2220 * Some signals have a process-wide effect and a per-thread
2221 * component. Most processing occurs when the process next
2222 * tries to cross the user boundary, however there are some
2223 * times when processing needs to be done immediately, such as
2224 * waking up threads so that they can cross the user boundary.
2225 * We try to do the per-process part here.
2227 if (P_SHOULDSTOP(p)) {
2228 KASSERT(!(p->p_flag & P_WEXIT),
2229 ("signal to stopped but exiting process"));
2230 if (sig == SIGKILL) {
2232 * If traced process is already stopped,
2233 * then no further action is necessary.
2235 if (p->p_flag & P_TRACED)
2238 * SIGKILL sets process running.
2239 * It will die elsewhere.
2240 * All threads must be restarted.
2242 p->p_flag &= ~P_STOPPED_SIG;
2246 if (prop & SIGPROP_CONT) {
2248 * If traced process is already stopped,
2249 * then no further action is necessary.
2251 if (p->p_flag & P_TRACED)
2254 * If SIGCONT is default (or ignored), we continue the
2255 * process but don't leave the signal in sigqueue as
2256 * it has no further action. If SIGCONT is held, we
2257 * continue the process and leave the signal in
2258 * sigqueue. If the process catches SIGCONT, let it
2259 * handle the signal itself. If it isn't waiting on
2260 * an event, it goes back to run state.
2261 * Otherwise, process goes back to sleep state.
2263 p->p_flag &= ~P_STOPPED_SIG;
2265 if (p->p_numthreads == p->p_suspcount) {
2267 p->p_flag |= P_CONTINUED;
2268 p->p_xsig = SIGCONT;
2269 PROC_LOCK(p->p_pptr);
2270 childproc_continued(p);
2271 PROC_UNLOCK(p->p_pptr);
2274 if (action == SIG_DFL) {
2275 thread_unsuspend(p);
2277 sigqueue_delete(sigqueue, sig);
2280 if (action == SIG_CATCH) {
2282 * The process wants to catch it so it needs
2283 * to run at least one thread, but which one?
2289 * The signal is not ignored or caught.
2291 thread_unsuspend(p);
2296 if (prop & SIGPROP_STOP) {
2298 * If traced process is already stopped,
2299 * then no further action is necessary.
2301 if (p->p_flag & P_TRACED)
2304 * Already stopped, don't need to stop again
2305 * (If we did the shell could get confused).
2306 * Just make sure the signal STOP bit set.
2308 p->p_flag |= P_STOPPED_SIG;
2309 sigqueue_delete(sigqueue, sig);
2314 * All other kinds of signals:
2315 * If a thread is sleeping interruptibly, simulate a
2316 * wakeup so that when it is continued it will be made
2317 * runnable and can look at the signal. However, don't make
2318 * the PROCESS runnable, leave it stopped.
2319 * It may run a bit until it hits a thread_suspend_check().
2324 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2325 wakeup_swapper = sleepq_abort(td, intrval);
2332 * Mutexes are short lived. Threads waiting on them will
2333 * hit thread_suspend_check() soon.
2335 } else if (p->p_state == PRS_NORMAL) {
2336 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2337 tdsigwakeup(td, sig, action, intrval);
2341 MPASS(action == SIG_DFL);
2343 if (prop & SIGPROP_STOP) {
2344 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2346 p->p_flag |= P_STOPPED_SIG;
2349 wakeup_swapper = sig_suspend_threads(td, p, 1);
2350 if (p->p_numthreads == p->p_suspcount) {
2352 * only thread sending signal to another
2353 * process can reach here, if thread is sending
2354 * signal to its process, because thread does
2355 * not suspend itself here, p_numthreads
2356 * should never be equal to p_suspcount.
2360 sigqueue_delete_proc(p, p->p_xsig);
2368 /* Not in "NORMAL" state. discard the signal. */
2369 sigqueue_delete(sigqueue, sig);
2374 * The process is not stopped so we need to apply the signal to all the
2378 tdsigwakeup(td, sig, action, intrval);
2380 thread_unsuspend(p);
2383 /* If we jump here, proc slock should not be owned. */
2384 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2389 * The force of a signal has been directed against a single
2390 * thread. We need to see what we can do about knocking it
2391 * out of any sleep it may be in etc.
2394 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2396 struct proc *p = td->td_proc;
2401 PROC_LOCK_ASSERT(p, MA_OWNED);
2402 prop = sigprop(sig);
2407 * Bring the priority of a thread up if we want it to get
2408 * killed in this lifetime. Be careful to avoid bumping the
2409 * priority of the idle thread, since we still allow to signal
2412 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2413 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2414 sched_prio(td, PUSER);
2415 if (TD_ON_SLEEPQ(td)) {
2417 * If thread is sleeping uninterruptibly
2418 * we can't interrupt the sleep... the signal will
2419 * be noticed when the process returns through
2420 * trap() or syscall().
2422 if ((td->td_flags & TDF_SINTR) == 0)
2425 * If SIGCONT is default (or ignored) and process is
2426 * asleep, we are finished; the process should not
2429 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2432 sigqueue_delete(&p->p_sigqueue, sig);
2434 * It may be on either list in this state.
2435 * Remove from both for now.
2437 sigqueue_delete(&td->td_sigqueue, sig);
2442 * Don't awaken a sleeping thread for SIGSTOP if the
2443 * STOP signal is deferred.
2445 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2446 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2450 * Give low priority threads a better chance to run.
2452 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2453 sched_prio(td, PUSER);
2455 wakeup_swapper = sleepq_abort(td, intrval);
2458 * Other states do nothing with the signal immediately,
2459 * other than kicking ourselves if we are running.
2460 * It will either never be noticed, or noticed very soon.
2463 if (TD_IS_RUNNING(td) && td != curthread)
2475 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2480 PROC_LOCK_ASSERT(p, MA_OWNED);
2481 PROC_SLOCK_ASSERT(p, MA_OWNED);
2482 MPASS(sending || td == curthread);
2485 FOREACH_THREAD_IN_PROC(p, td2) {
2487 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2488 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2489 (td2->td_flags & TDF_SINTR)) {
2490 if (td2->td_flags & TDF_SBDRY) {
2492 * Once a thread is asleep with
2493 * TDF_SBDRY and without TDF_SERESTART
2494 * or TDF_SEINTR set, it should never
2495 * become suspended due to this check.
2497 KASSERT(!TD_IS_SUSPENDED(td2),
2498 ("thread with deferred stops suspended"));
2499 if (TD_SBDRY_INTR(td2))
2500 wakeup_swapper |= sleepq_abort(td2,
2501 TD_SBDRY_ERRNO(td2));
2502 } else if (!TD_IS_SUSPENDED(td2)) {
2503 thread_suspend_one(td2);
2505 } else if (!TD_IS_SUSPENDED(td2)) {
2506 if (sending || td != td2)
2507 td2->td_flags |= TDF_ASTPENDING;
2509 if (TD_IS_RUNNING(td2) && td2 != td)
2510 forward_signal(td2);
2515 return (wakeup_swapper);
2519 * Stop the process for an event deemed interesting to the debugger. If si is
2520 * non-NULL, this is a signal exchange; the new signal requested by the
2521 * debugger will be returned for handling. If si is NULL, this is some other
2522 * type of interesting event. The debugger may request a signal be delivered in
2523 * that case as well, however it will be deferred until it can be handled.
2526 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2528 struct proc *p = td->td_proc;
2533 PROC_LOCK_ASSERT(p, MA_OWNED);
2534 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2535 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2536 &p->p_mtx.lock_object, "Stopping for traced signal");
2540 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2541 td->td_dbgflags |= TDB_XSIG;
2542 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2543 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2545 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2548 * Ensure that, if we've been PT_KILLed, the
2549 * exit status reflects that. Another thread
2550 * may also be in ptracestop(), having just
2551 * received the SIGKILL, but this thread was
2552 * unsuspended first.
2554 td->td_dbgflags &= ~TDB_XSIG;
2555 td->td_xsig = SIGKILL;
2559 if (p->p_flag & P_SINGLE_EXIT &&
2560 !(td->td_dbgflags & TDB_EXIT)) {
2562 * Ignore ptrace stops except for thread exit
2563 * events when the process exits.
2565 td->td_dbgflags &= ~TDB_XSIG;
2571 * Make wait(2) work. Ensure that right after the
2572 * attach, the thread which was decided to become the
2573 * leader of attach gets reported to the waiter.
2574 * Otherwise, just avoid overwriting another thread's
2575 * assignment to p_xthread. If another thread has
2576 * already set p_xthread, the current thread will get
2577 * a chance to report itself upon the next iteration.
2579 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2580 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2581 p->p_xthread == NULL)) {
2584 td->td_dbgflags &= ~TDB_FSTP;
2585 p->p_flag2 &= ~P2_PTRACE_FSTP;
2586 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2587 sig_suspend_threads(td, p, 0);
2589 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2590 td->td_dbgflags &= ~TDB_STOPATFORK;
2591 cv_broadcast(&p->p_dbgwait);
2594 thread_suspend_switch(td, p);
2595 if (p->p_xthread == td)
2596 p->p_xthread = NULL;
2597 if (!(p->p_flag & P_TRACED))
2599 if (td->td_dbgflags & TDB_SUSPEND) {
2600 if (p->p_flag & P_SINGLE_EXIT)
2608 if (si != NULL && sig == td->td_xsig) {
2609 /* Parent wants us to take the original signal unchanged. */
2610 si->ksi_flags |= KSI_HEAD;
2611 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2613 } else if (td->td_xsig != 0) {
2615 * If parent wants us to take a new signal, then it will leave
2616 * it in td->td_xsig; otherwise we just look for signals again.
2618 ksiginfo_init(&ksi);
2619 ksi.ksi_signo = td->td_xsig;
2620 ksi.ksi_flags |= KSI_PTRACE;
2621 prop = sigprop(td->td_xsig);
2622 td2 = sigtd(p, td->td_xsig, prop);
2623 tdsendsignal(p, td2, td->td_xsig, &ksi);
2628 return (td->td_xsig);
2632 reschedule_signals(struct proc *p, sigset_t block, int flags)
2638 PROC_LOCK_ASSERT(p, MA_OWNED);
2640 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2641 MA_OWNED : MA_NOTOWNED);
2642 if (SIGISEMPTY(p->p_siglist))
2644 SIGSETAND(block, p->p_siglist);
2645 while ((sig = sig_ffs(&block)) != 0) {
2646 SIGDELSET(block, sig);
2647 td = sigtd(p, sig, 0);
2649 if (!(flags & SIGPROCMASK_PS_LOCKED))
2650 mtx_lock(&ps->ps_mtx);
2651 if (p->p_flag & P_TRACED ||
2652 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2653 !SIGISMEMBER(td->td_sigmask, sig)))
2654 tdsigwakeup(td, sig, SIG_CATCH,
2655 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2657 if (!(flags & SIGPROCMASK_PS_LOCKED))
2658 mtx_unlock(&ps->ps_mtx);
2663 tdsigcleanup(struct thread *td)
2669 PROC_LOCK_ASSERT(p, MA_OWNED);
2671 sigqueue_flush(&td->td_sigqueue);
2672 if (p->p_numthreads == 1)
2676 * Since we cannot handle signals, notify signal post code
2677 * about this by filling the sigmask.
2679 * Also, if needed, wake up thread(s) that do not block the
2680 * same signals as the exiting thread, since the thread might
2681 * have been selected for delivery and woken up.
2683 SIGFILLSET(unblocked);
2684 SIGSETNAND(unblocked, td->td_sigmask);
2685 SIGFILLSET(td->td_sigmask);
2686 reschedule_signals(p, unblocked, 0);
2691 sigdeferstop_curr_flags(int cflags)
2694 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2695 (cflags & TDF_SBDRY) != 0);
2696 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2700 * Defer the delivery of SIGSTOP for the current thread, according to
2701 * the requested mode. Returns previous flags, which must be restored
2702 * by sigallowstop().
2704 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2705 * cleared by the current thread, which allow the lock-less read-only
2709 sigdeferstop_impl(int mode)
2715 cflags = sigdeferstop_curr_flags(td->td_flags);
2717 case SIGDEFERSTOP_NOP:
2720 case SIGDEFERSTOP_OFF:
2723 case SIGDEFERSTOP_SILENT:
2724 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2726 case SIGDEFERSTOP_EINTR:
2727 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2729 case SIGDEFERSTOP_ERESTART:
2730 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2733 panic("sigdeferstop: invalid mode %x", mode);
2736 if (cflags == nflags)
2737 return (SIGDEFERSTOP_VAL_NCHG);
2739 td->td_flags = (td->td_flags & ~cflags) | nflags;
2745 * Restores the STOP handling mode, typically permitting the delivery
2746 * of SIGSTOP for the current thread. This does not immediately
2747 * suspend if a stop was posted. Instead, the thread will suspend
2748 * either via ast() or a subsequent interruptible sleep.
2751 sigallowstop_impl(int prev)
2756 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2757 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2758 ("sigallowstop: incorrect previous mode %x", prev));
2760 cflags = sigdeferstop_curr_flags(td->td_flags);
2761 if (cflags != prev) {
2763 td->td_flags = (td->td_flags & ~cflags) | prev;
2769 * If the current process has received a signal (should be caught or cause
2770 * termination, should interrupt current syscall), return the signal number.
2771 * Stop signals with default action are processed immediately, then cleared;
2772 * they aren't returned. This is checked after each entry to the system for
2773 * a syscall or trap (though this can usually be done without calling issignal
2774 * by checking the pending signal masks in cursig.) The normal call
2777 * while (sig = cursig(curthread))
2781 issignal(struct thread *td)
2785 struct sigqueue *queue;
2786 sigset_t sigpending;
2788 int prop, sig, traced;
2792 mtx_assert(&ps->ps_mtx, MA_OWNED);
2793 PROC_LOCK_ASSERT(p, MA_OWNED);
2795 traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2797 sigpending = td->td_sigqueue.sq_signals;
2798 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2799 SIGSETNAND(sigpending, td->td_sigmask);
2801 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
2802 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2803 SIG_STOPSIGMASK(sigpending);
2804 if (SIGISEMPTY(sigpending)) /* no signal to send */
2806 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2807 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2808 SIGISMEMBER(sigpending, SIGSTOP)) {
2810 * If debugger just attached, always consume
2811 * SIGSTOP from ptrace(PT_ATTACH) first, to
2812 * execute the debugger attach ritual in
2816 td->td_dbgflags |= TDB_FSTP;
2818 sig = sig_ffs(&sigpending);
2821 if (p->p_stops & S_SIG) {
2822 mtx_unlock(&ps->ps_mtx);
2823 stopevent(p, S_SIG, sig);
2824 mtx_lock(&ps->ps_mtx);
2828 * We should see pending but ignored signals
2829 * only if P_TRACED was on when they were posted.
2831 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2832 sigqueue_delete(&td->td_sigqueue, sig);
2833 sigqueue_delete(&p->p_sigqueue, sig);
2836 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2838 * If traced, always stop.
2839 * Remove old signal from queue before the stop.
2840 * XXX shrug off debugger, it causes siginfo to
2843 queue = &td->td_sigqueue;
2844 ksiginfo_init(&ksi);
2845 if (sigqueue_get(queue, sig, &ksi) == 0) {
2846 queue = &p->p_sigqueue;
2847 sigqueue_get(queue, sig, &ksi);
2849 td->td_si = ksi.ksi_info;
2851 mtx_unlock(&ps->ps_mtx);
2852 sig = ptracestop(td, sig, &ksi);
2853 mtx_lock(&ps->ps_mtx);
2856 * Keep looking if the debugger discarded or
2857 * replaced the signal.
2863 * If the signal became masked, re-queue it.
2865 if (SIGISMEMBER(td->td_sigmask, sig)) {
2866 ksi.ksi_flags |= KSI_HEAD;
2867 sigqueue_add(&p->p_sigqueue, sig, &ksi);
2872 * If the traced bit got turned off, requeue
2873 * the signal and go back up to the top to
2874 * rescan signals. This ensures that p_sig*
2875 * and p_sigact are consistent.
2877 if ((p->p_flag & P_TRACED) == 0) {
2878 ksi.ksi_flags |= KSI_HEAD;
2879 sigqueue_add(queue, sig, &ksi);
2884 prop = sigprop(sig);
2887 * Decide whether the signal should be returned.
2888 * Return the signal's number, or fall through
2889 * to clear it from the pending mask.
2891 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2893 case (intptr_t)SIG_DFL:
2895 * Don't take default actions on system processes.
2897 if (p->p_pid <= 1) {
2900 * Are you sure you want to ignore SIGSEGV
2903 printf("Process (pid %lu) got signal %d\n",
2904 (u_long)p->p_pid, sig);
2906 break; /* == ignore */
2909 * If there is a pending stop signal to process with
2910 * default action, stop here, then clear the signal.
2911 * Traced or exiting processes should ignore stops.
2912 * Additionally, a member of an orphaned process group
2913 * should ignore tty stops.
2915 if (prop & SIGPROP_STOP) {
2917 (P_TRACED | P_WEXIT | P_SINGLE_EXIT) ||
2918 (p->p_pgrp->pg_jobc == 0 &&
2919 prop & SIGPROP_TTYSTOP))
2920 break; /* == ignore */
2921 if (TD_SBDRY_INTR(td)) {
2922 KASSERT((td->td_flags & TDF_SBDRY) != 0,
2923 ("lost TDF_SBDRY"));
2926 mtx_unlock(&ps->ps_mtx);
2927 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2928 &p->p_mtx.lock_object, "Catching SIGSTOP");
2929 sigqueue_delete(&td->td_sigqueue, sig);
2930 sigqueue_delete(&p->p_sigqueue, sig);
2931 p->p_flag |= P_STOPPED_SIG;
2934 sig_suspend_threads(td, p, 0);
2935 thread_suspend_switch(td, p);
2937 mtx_lock(&ps->ps_mtx);
2939 } else if (prop & SIGPROP_IGNORE) {
2941 * Except for SIGCONT, shouldn't get here.
2942 * Default action is to ignore; drop it.
2944 break; /* == ignore */
2949 case (intptr_t)SIG_IGN:
2951 * Masking above should prevent us ever trying
2952 * to take action on an ignored signal other
2953 * than SIGCONT, unless process is traced.
2955 if ((prop & SIGPROP_CONT) == 0 &&
2956 (p->p_flag & P_TRACED) == 0)
2957 printf("issignal\n");
2958 break; /* == ignore */
2962 * This signal has an action, let
2963 * postsig() process it.
2967 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2968 sigqueue_delete(&p->p_sigqueue, sig);
2975 thread_stopped(struct proc *p)
2979 PROC_LOCK_ASSERT(p, MA_OWNED);
2980 PROC_SLOCK_ASSERT(p, MA_OWNED);
2984 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2986 p->p_flag &= ~P_WAITED;
2987 PROC_LOCK(p->p_pptr);
2988 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2989 CLD_TRAPPED : CLD_STOPPED);
2990 PROC_UNLOCK(p->p_pptr);
2996 * Take the action for the specified signal
2997 * from the current set of pending signals.
3007 sigset_t returnmask;
3009 KASSERT(sig != 0, ("postsig"));
3013 PROC_LOCK_ASSERT(p, MA_OWNED);
3015 mtx_assert(&ps->ps_mtx, MA_OWNED);
3016 ksiginfo_init(&ksi);
3017 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3018 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3020 ksi.ksi_signo = sig;
3021 if (ksi.ksi_code == SI_TIMER)
3022 itimer_accept(p, ksi.ksi_timerid, &ksi);
3023 action = ps->ps_sigact[_SIG_IDX(sig)];
3025 if (KTRPOINT(td, KTR_PSIG))
3026 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3027 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3029 if ((p->p_stops & S_SIG) != 0) {
3030 mtx_unlock(&ps->ps_mtx);
3031 stopevent(p, S_SIG, sig);
3032 mtx_lock(&ps->ps_mtx);
3035 if (action == SIG_DFL) {
3037 * Default action, where the default is to kill
3038 * the process. (Other cases were ignored above.)
3040 mtx_unlock(&ps->ps_mtx);
3041 proc_td_siginfo_capture(td, &ksi.ksi_info);
3046 * If we get here, the signal must be caught.
3048 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3049 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3050 ("postsig action: blocked sig %d", sig));
3053 * Set the new mask value and also defer further
3054 * occurrences of this signal.
3056 * Special case: user has done a sigsuspend. Here the
3057 * current mask is not of interest, but rather the
3058 * mask from before the sigsuspend is what we want
3059 * restored after the signal processing is completed.
3061 if (td->td_pflags & TDP_OLDMASK) {
3062 returnmask = td->td_oldsigmask;
3063 td->td_pflags &= ~TDP_OLDMASK;
3065 returnmask = td->td_sigmask;
3067 if (p->p_sig == sig) {
3071 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3072 postsig_done(sig, td, ps);
3078 * Kill the current process for stated reason.
3081 killproc(struct proc *p, char *why)
3084 PROC_LOCK_ASSERT(p, MA_OWNED);
3085 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3087 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
3088 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
3089 p->p_flag |= P_WKILLED;
3090 kern_psignal(p, SIGKILL);
3094 * Force the current process to exit with the specified signal, dumping core
3095 * if appropriate. We bypass the normal tests for masked and caught signals,
3096 * allowing unrecoverable failures to terminate the process without changing
3097 * signal state. Mark the accounting record with the signal termination.
3098 * If dumping core, save the signal number for the debugger. Calls exit and
3102 sigexit(struct thread *td, int sig)
3104 struct proc *p = td->td_proc;
3106 PROC_LOCK_ASSERT(p, MA_OWNED);
3107 p->p_acflag |= AXSIG;
3109 * We must be single-threading to generate a core dump. This
3110 * ensures that the registers in the core file are up-to-date.
3111 * Also, the ELF dump handler assumes that the thread list doesn't
3112 * change out from under it.
3114 * XXX If another thread attempts to single-thread before us
3115 * (e.g. via fork()), we won't get a dump at all.
3117 if ((sigprop(sig) & SIGPROP_CORE) &&
3118 thread_single(p, SINGLE_NO_EXIT) == 0) {
3121 * Log signals which would cause core dumps
3122 * (Log as LOG_INFO to appease those who don't want
3124 * XXX : Todo, as well as euid, write out ruid too
3125 * Note that coredump() drops proc lock.
3127 if (coredump(td) == 0)
3129 if (kern_logsigexit)
3131 "pid %d (%s), uid %d: exited on signal %d%s\n",
3132 p->p_pid, p->p_comm,
3133 td->td_ucred ? td->td_ucred->cr_uid : -1,
3135 sig & WCOREFLAG ? " (core dumped)" : "");
3143 * Send queued SIGCHLD to parent when child process's state
3147 sigparent(struct proc *p, int reason, int status)
3149 PROC_LOCK_ASSERT(p, MA_OWNED);
3150 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3152 if (p->p_ksi != NULL) {
3153 p->p_ksi->ksi_signo = SIGCHLD;
3154 p->p_ksi->ksi_code = reason;
3155 p->p_ksi->ksi_status = status;
3156 p->p_ksi->ksi_pid = p->p_pid;
3157 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3158 if (KSI_ONQ(p->p_ksi))
3161 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3165 childproc_jobstate(struct proc *p, int reason, int sig)
3169 PROC_LOCK_ASSERT(p, MA_OWNED);
3170 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3173 * Wake up parent sleeping in kern_wait(), also send
3174 * SIGCHLD to parent, but SIGCHLD does not guarantee
3175 * that parent will awake, because parent may masked
3178 p->p_pptr->p_flag |= P_STATCHILD;
3181 ps = p->p_pptr->p_sigacts;
3182 mtx_lock(&ps->ps_mtx);
3183 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3184 mtx_unlock(&ps->ps_mtx);
3185 sigparent(p, reason, sig);
3187 mtx_unlock(&ps->ps_mtx);
3191 childproc_stopped(struct proc *p, int reason)
3194 childproc_jobstate(p, reason, p->p_xsig);
3198 childproc_continued(struct proc *p)
3200 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3204 childproc_exited(struct proc *p)
3208 if (WCOREDUMP(p->p_xsig)) {
3209 reason = CLD_DUMPED;
3210 status = WTERMSIG(p->p_xsig);
3211 } else if (WIFSIGNALED(p->p_xsig)) {
3212 reason = CLD_KILLED;
3213 status = WTERMSIG(p->p_xsig);
3215 reason = CLD_EXITED;
3216 status = p->p_xexit;
3219 * XXX avoid calling wakeup(p->p_pptr), the work is
3222 sigparent(p, reason, status);
3226 * We only have 1 character for the core count in the format
3227 * string, so the range will be 0-9
3229 #define MAX_NUM_CORE_FILES 10
3230 #ifndef NUM_CORE_FILES
3231 #define NUM_CORE_FILES 5
3233 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3234 static int num_cores = NUM_CORE_FILES;
3237 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3242 new_val = num_cores;
3243 error = sysctl_handle_int(oidp, &new_val, 0, req);
3244 if (error != 0 || req->newptr == NULL)
3246 if (new_val > MAX_NUM_CORE_FILES)
3247 new_val = MAX_NUM_CORE_FILES;
3250 num_cores = new_val;
3253 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3254 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3256 #define GZIP_SUFFIX ".gz"
3257 #define ZSTD_SUFFIX ".zst"
3259 int compress_user_cores = 0;
3262 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3266 val = compress_user_cores;
3267 error = sysctl_handle_int(oidp, &val, 0, req);
3268 if (error != 0 || req->newptr == NULL)
3270 if (val != 0 && !compressor_avail(val))
3272 compress_user_cores = val;
3275 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores, CTLTYPE_INT | CTLFLAG_RWTUN,
3276 0, sizeof(int), sysctl_compress_user_cores, "I",
3277 "Enable compression of user corefiles ("
3278 __XSTRING(COMPRESS_GZIP) " = gzip, "
3279 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3281 int compress_user_cores_level = 6;
3282 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3283 &compress_user_cores_level, 0,
3284 "Corefile compression level");
3287 * Protect the access to corefilename[] by allproc_lock.
3289 #define corefilename_lock allproc_lock
3291 static char corefilename[MAXPATHLEN] = {"%N.core"};
3292 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3295 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3299 sx_xlock(&corefilename_lock);
3300 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3302 sx_xunlock(&corefilename_lock);
3306 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3307 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3308 "Process corefile name format string");
3311 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3312 * Expand the name described in corefilename, using name, uid, and pid
3313 * and open/create core file.
3314 * corefilename is a printf-like string, with three format specifiers:
3315 * %N name of process ("name")
3316 * %P process id (pid)
3318 * For example, "%N.core" is the default; they can be disabled completely
3319 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3320 * This is controlled by the sysctl variable kern.corefile (see above).
3323 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3324 int compress, struct vnode **vpp, char **namep)
3326 struct nameidata nd;
3329 char *hostname, *name;
3330 int indexpos, i, error, cmode, flags, oflags;
3333 format = corefilename;
3334 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3336 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3337 sx_slock(&corefilename_lock);
3338 for (i = 0; format[i] != '\0'; i++) {
3339 switch (format[i]) {
3340 case '%': /* Format character */
3342 switch (format[i]) {
3344 sbuf_putc(&sb, '%');
3346 case 'H': /* hostname */
3347 if (hostname == NULL) {
3348 hostname = malloc(MAXHOSTNAMELEN,
3351 getcredhostname(td->td_ucred, hostname,
3353 sbuf_printf(&sb, "%s", hostname);
3355 case 'I': /* autoincrementing index */
3356 sbuf_printf(&sb, "0");
3357 indexpos = sbuf_len(&sb) - 1;
3359 case 'N': /* process name */
3360 sbuf_printf(&sb, "%s", comm);
3362 case 'P': /* process id */
3363 sbuf_printf(&sb, "%u", pid);
3365 case 'U': /* user id */
3366 sbuf_printf(&sb, "%u", uid);
3370 "Unknown format character %c in "
3371 "corename `%s'\n", format[i], format);
3376 sbuf_putc(&sb, format[i]);
3380 sx_sunlock(&corefilename_lock);
3381 free(hostname, M_TEMP);
3382 if (compress == COMPRESS_GZIP)
3383 sbuf_printf(&sb, GZIP_SUFFIX);
3384 else if (compress == COMPRESS_ZSTD)
3385 sbuf_printf(&sb, ZSTD_SUFFIX);
3386 if (sbuf_error(&sb) != 0) {
3387 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3388 "long\n", (long)pid, comm, (u_long)uid);
3396 cmode = S_IRUSR | S_IWUSR;
3397 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3398 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3401 * If the core format has a %I in it, then we need to check
3402 * for existing corefiles before returning a name.
3403 * To do this we iterate over 0..num_cores to find a
3404 * non-existing core file name to use.
3406 if (indexpos != -1) {
3407 for (i = 0; i < num_cores; i++) {
3408 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3409 name[indexpos] = '0' + i;
3410 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3411 error = vn_open_cred(&nd, &flags, cmode, oflags,
3412 td->td_ucred, NULL);
3414 if (error == EEXIST)
3417 "pid %d (%s), uid (%u): Path `%s' failed "
3418 "on initial open test, error = %d\n",
3419 pid, comm, uid, name, error);
3425 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3426 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3427 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3431 audit_proc_coredump(td, name, error);
3436 NDFREE(&nd, NDF_ONLY_PNBUF);
3443 coredump_sanitise_path(const char *path)
3448 * Only send a subset of ASCII to devd(8) because it
3449 * might pass these strings to sh -c.
3451 for (i = 0; path[i]; i++)
3452 if (!(isalpha(path[i]) || isdigit(path[i])) &&
3453 path[i] != '/' && path[i] != '.' &&
3461 * Dump a process' core. The main routine does some
3462 * policy checking, and creates the name of the coredump;
3463 * then it passes on a vnode and a size limit to the process-specific
3464 * coredump routine if there is one; if there _is not_ one, it returns
3465 * ENOSYS; otherwise it returns the error from the process-specific routine.
3469 coredump(struct thread *td)
3471 struct proc *p = td->td_proc;
3472 struct ucred *cred = td->td_ucred;
3476 int error, error1, locked;
3477 char *name; /* name of corefile */
3481 char *fullpath, *freepath = NULL;
3483 static const char comm_name[] = "comm=";
3484 static const char core_name[] = "core=";
3486 PROC_LOCK_ASSERT(p, MA_OWNED);
3487 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3488 _STOPEVENT(p, S_CORE, 0);
3490 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3491 (p->p_flag2 & P2_NOTRACE) != 0) {
3497 * Note that the bulk of limit checking is done after
3498 * the corefile is created. The exception is if the limit
3499 * for corefiles is 0, in which case we don't bother
3500 * creating the corefile at all. This layout means that
3501 * a corefile is truncated instead of not being created,
3502 * if it is larger than the limit.
3504 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3505 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3511 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3512 compress_user_cores, &vp, &name);
3517 * Don't dump to non-regular files or files with links.
3518 * Do not dump into system files.
3520 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3521 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0) {
3529 /* Postpone other writers, including core dumps of other processes. */
3530 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3532 lf.l_whence = SEEK_SET;
3535 lf.l_type = F_WRLCK;
3536 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3540 if (set_core_nodump_flag)
3541 vattr.va_flags = UF_NODUMP;
3542 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3543 VOP_SETATTR(vp, &vattr, cred);
3546 p->p_acflag |= ACORE;
3549 if (p->p_sysent->sv_coredump != NULL) {
3550 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3556 lf.l_type = F_UNLCK;
3557 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3559 vn_rangelock_unlock(vp, rl_cookie);
3562 * Notify the userland helper that a process triggered a core dump.
3563 * This allows the helper to run an automated debugging session.
3565 if (error != 0 || coredump_devctl == 0)
3567 len = MAXPATHLEN * 2 + sizeof(comm_name) - 1 +
3568 sizeof(' ') + sizeof(core_name) - 1;
3569 data = malloc(len, M_TEMP, M_WAITOK);
3570 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3572 if (!coredump_sanitise_path(fullpath))
3574 snprintf(data, len, "%s%s ", comm_name, fullpath);
3575 free(freepath, M_TEMP);
3577 if (vn_fullpath_global(td, vp, &fullpath, &freepath) != 0)
3579 if (!coredump_sanitise_path(fullpath))
3581 strlcat(data, core_name, len);
3582 strlcat(data, fullpath, len);
3583 devctl_notify("kernel", "signal", "coredump", data);
3585 error1 = vn_close(vp, FWRITE, cred, td);
3589 audit_proc_coredump(td, name, error);
3591 free(freepath, M_TEMP);
3598 * Nonexistent system call-- signal process (may want to handle it). Flag
3599 * error in case process won't see signal immediately (blocked or ignored).
3601 #ifndef _SYS_SYSPROTO_H_
3608 nosys(struct thread *td, struct nosys_args *args)
3615 tdsignal(td, SIGSYS);
3617 if (kern_lognosys == 1 || kern_lognosys == 3) {
3618 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3621 if (kern_lognosys == 2 || kern_lognosys == 3) {
3622 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3629 * Send a SIGIO or SIGURG signal to a process or process group using stored
3630 * credentials rather than those of the current process.
3633 pgsigio(struct sigio **sigiop, int sig, int checkctty)
3636 struct sigio *sigio;
3638 ksiginfo_init(&ksi);
3639 ksi.ksi_signo = sig;
3640 ksi.ksi_code = SI_KERNEL;
3644 if (sigio == NULL) {
3648 if (sigio->sio_pgid > 0) {
3649 PROC_LOCK(sigio->sio_proc);
3650 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3651 kern_psignal(sigio->sio_proc, sig);
3652 PROC_UNLOCK(sigio->sio_proc);
3653 } else if (sigio->sio_pgid < 0) {
3656 PGRP_LOCK(sigio->sio_pgrp);
3657 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3659 if (p->p_state == PRS_NORMAL &&
3660 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3661 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3662 kern_psignal(p, sig);
3665 PGRP_UNLOCK(sigio->sio_pgrp);
3671 filt_sigattach(struct knote *kn)
3673 struct proc *p = curproc;
3675 kn->kn_ptr.p_proc = p;
3676 kn->kn_flags |= EV_CLEAR; /* automatically set */
3678 knlist_add(p->p_klist, kn, 0);
3684 filt_sigdetach(struct knote *kn)
3686 struct proc *p = kn->kn_ptr.p_proc;
3688 knlist_remove(p->p_klist, kn, 0);
3692 * signal knotes are shared with proc knotes, so we apply a mask to
3693 * the hint in order to differentiate them from process hints. This
3694 * could be avoided by using a signal-specific knote list, but probably
3695 * isn't worth the trouble.
3698 filt_signal(struct knote *kn, long hint)
3701 if (hint & NOTE_SIGNAL) {
3702 hint &= ~NOTE_SIGNAL;
3704 if (kn->kn_id == hint)
3707 return (kn->kn_data != 0);
3715 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3716 refcount_init(&ps->ps_refcnt, 1);
3717 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3722 sigacts_free(struct sigacts *ps)
3725 if (refcount_release(&ps->ps_refcnt) == 0)
3727 mtx_destroy(&ps->ps_mtx);
3728 free(ps, M_SUBPROC);
3732 sigacts_hold(struct sigacts *ps)
3735 refcount_acquire(&ps->ps_refcnt);
3740 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3743 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3744 mtx_lock(&src->ps_mtx);
3745 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3746 mtx_unlock(&src->ps_mtx);
3750 sigacts_shared(struct sigacts *ps)
3753 return (ps->ps_refcnt > 1);