2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
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9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
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13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
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20 * 3. Neither the name of the University nor the names of its contributors
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24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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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_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 memset(oact, 0, sizeof(*oact));
698 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) {
1680 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1681 p == td->td_proc || p->p_state == PRS_NEW) {
1685 err = p_cansignal(td, p, sig);
1688 pksignal(p, sig, ksi);
1691 else if (ret == ESRCH)
1695 sx_sunlock(&allproc_lock);
1697 sx_slock(&proctree_lock);
1700 * zero pgid means send to my process group.
1702 pgrp = td->td_proc->p_pgrp;
1705 pgrp = pgfind(pgid);
1707 sx_sunlock(&proctree_lock);
1711 sx_sunlock(&proctree_lock);
1712 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1714 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1715 p->p_state == PRS_NEW) {
1719 err = p_cansignal(td, p, sig);
1722 pksignal(p, sig, ksi);
1725 else if (ret == ESRCH)
1734 #ifndef _SYS_SYSPROTO_H_
1742 sys_kill(struct thread *td, struct kill_args *uap)
1749 * A process in capability mode can send signals only to himself.
1750 * The main rationale behind this is that abort(3) is implemented as
1751 * kill(getpid(), SIGABRT).
1753 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1756 AUDIT_ARG_SIGNUM(uap->signum);
1757 AUDIT_ARG_PID(uap->pid);
1758 if ((u_int)uap->signum > _SIG_MAXSIG)
1761 ksiginfo_init(&ksi);
1762 ksi.ksi_signo = uap->signum;
1763 ksi.ksi_code = SI_USER;
1764 ksi.ksi_pid = td->td_proc->p_pid;
1765 ksi.ksi_uid = td->td_ucred->cr_ruid;
1768 /* kill single process */
1769 if ((p = pfind_any(uap->pid)) == NULL)
1771 AUDIT_ARG_PROCESS(p);
1772 error = p_cansignal(td, p, uap->signum);
1773 if (error == 0 && uap->signum)
1774 pksignal(p, uap->signum, &ksi);
1779 case -1: /* broadcast signal */
1780 return (killpg1(td, uap->signum, 0, 1, &ksi));
1781 case 0: /* signal own process group */
1782 return (killpg1(td, uap->signum, 0, 0, &ksi));
1783 default: /* negative explicit process group */
1784 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1790 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1793 cap_rights_t rights;
1796 AUDIT_ARG_SIGNUM(uap->signum);
1797 AUDIT_ARG_FD(uap->fd);
1798 if ((u_int)uap->signum > _SIG_MAXSIG)
1801 error = procdesc_find(td, uap->fd,
1802 cap_rights_init(&rights, CAP_PDKILL), &p);
1805 AUDIT_ARG_PROCESS(p);
1806 error = p_cansignal(td, p, uap->signum);
1807 if (error == 0 && uap->signum)
1808 kern_psignal(p, uap->signum);
1813 #if defined(COMPAT_43)
1814 #ifndef _SYS_SYSPROTO_H_
1815 struct okillpg_args {
1822 okillpg(struct thread *td, struct okillpg_args *uap)
1826 AUDIT_ARG_SIGNUM(uap->signum);
1827 AUDIT_ARG_PID(uap->pgid);
1828 if ((u_int)uap->signum > _SIG_MAXSIG)
1831 ksiginfo_init(&ksi);
1832 ksi.ksi_signo = uap->signum;
1833 ksi.ksi_code = SI_USER;
1834 ksi.ksi_pid = td->td_proc->p_pid;
1835 ksi.ksi_uid = td->td_ucred->cr_ruid;
1836 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1838 #endif /* COMPAT_43 */
1840 #ifndef _SYS_SYSPROTO_H_
1841 struct sigqueue_args {
1844 /* union sigval */ void *value;
1848 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1852 sv.sival_ptr = uap->value;
1854 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1858 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1864 if ((u_int)signum > _SIG_MAXSIG)
1868 * Specification says sigqueue can only send signal to
1874 if ((p = pfind_any(pid)) == NULL)
1876 error = p_cansignal(td, p, signum);
1877 if (error == 0 && signum != 0) {
1878 ksiginfo_init(&ksi);
1879 ksi.ksi_flags = KSI_SIGQ;
1880 ksi.ksi_signo = signum;
1881 ksi.ksi_code = SI_QUEUE;
1882 ksi.ksi_pid = td->td_proc->p_pid;
1883 ksi.ksi_uid = td->td_ucred->cr_ruid;
1884 ksi.ksi_value = *value;
1885 error = pksignal(p, ksi.ksi_signo, &ksi);
1892 * Send a signal to a process group.
1895 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1900 sx_slock(&proctree_lock);
1901 pgrp = pgfind(pgid);
1902 sx_sunlock(&proctree_lock);
1904 pgsignal(pgrp, sig, 0, ksi);
1911 * Send a signal to a process group. If checktty is 1,
1912 * limit to members which have a controlling terminal.
1915 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1920 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1921 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1923 if (p->p_state == PRS_NORMAL &&
1924 (checkctty == 0 || p->p_flag & P_CONTROLT))
1925 pksignal(p, sig, ksi);
1933 * Recalculate the signal mask and reset the signal disposition after
1934 * usermode frame for delivery is formed. Should be called after
1935 * mach-specific routine, because sysent->sv_sendsig() needs correct
1936 * ps_siginfo and signal mask.
1939 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1943 mtx_assert(&ps->ps_mtx, MA_OWNED);
1944 td->td_ru.ru_nsignals++;
1945 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1946 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1947 SIGADDSET(mask, sig);
1948 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1949 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1950 if (SIGISMEMBER(ps->ps_sigreset, sig))
1956 * Send a signal caused by a trap to the current thread. If it will be
1957 * caught immediately, deliver it with correct code. Otherwise, post it
1961 trapsignal(struct thread *td, ksiginfo_t *ksi)
1969 sig = ksi->ksi_signo;
1970 code = ksi->ksi_code;
1971 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1975 mtx_lock(&ps->ps_mtx);
1976 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1977 !SIGISMEMBER(td->td_sigmask, sig)) {
1979 if (KTRPOINT(curthread, KTR_PSIG))
1980 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1981 &td->td_sigmask, code);
1983 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1984 ksi, &td->td_sigmask);
1985 postsig_done(sig, td, ps);
1986 mtx_unlock(&ps->ps_mtx);
1989 * Avoid a possible infinite loop if the thread
1990 * masking the signal or process is ignoring the
1993 if (kern_forcesigexit &&
1994 (SIGISMEMBER(td->td_sigmask, sig) ||
1995 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1996 SIGDELSET(td->td_sigmask, sig);
1997 SIGDELSET(ps->ps_sigcatch, sig);
1998 SIGDELSET(ps->ps_sigignore, sig);
1999 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2001 mtx_unlock(&ps->ps_mtx);
2002 p->p_code = code; /* XXX for core dump/debugger */
2003 p->p_sig = sig; /* XXX to verify code */
2004 tdsendsignal(p, td, sig, ksi);
2009 static struct thread *
2010 sigtd(struct proc *p, int sig, int prop)
2012 struct thread *td, *signal_td;
2014 PROC_LOCK_ASSERT(p, MA_OWNED);
2017 * Check if current thread can handle the signal without
2018 * switching context to another thread.
2020 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
2023 FOREACH_THREAD_IN_PROC(p, td) {
2024 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2029 if (signal_td == NULL)
2030 signal_td = FIRST_THREAD_IN_PROC(p);
2035 * Send the signal to the process. If the signal has an action, the action
2036 * is usually performed by the target process rather than the caller; we add
2037 * the signal to the set of pending signals for the process.
2040 * o When a stop signal is sent to a sleeping process that takes the
2041 * default action, the process is stopped without awakening it.
2042 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2043 * regardless of the signal action (eg, blocked or ignored).
2045 * Other ignored signals are discarded immediately.
2047 * NB: This function may be entered from the debugger via the "kill" DDB
2048 * command. There is little that can be done to mitigate the possibly messy
2049 * side effects of this unwise possibility.
2052 kern_psignal(struct proc *p, int sig)
2056 ksiginfo_init(&ksi);
2057 ksi.ksi_signo = sig;
2058 ksi.ksi_code = SI_KERNEL;
2059 (void) tdsendsignal(p, NULL, sig, &ksi);
2063 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2066 return (tdsendsignal(p, NULL, sig, ksi));
2069 /* Utility function for finding a thread to send signal event to. */
2071 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2075 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2076 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2088 tdsignal(struct thread *td, int sig)
2092 ksiginfo_init(&ksi);
2093 ksi.ksi_signo = sig;
2094 ksi.ksi_code = SI_KERNEL;
2095 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2099 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2102 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2106 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2109 sigqueue_t *sigqueue;
2116 MPASS(td == NULL || p == td->td_proc);
2117 PROC_LOCK_ASSERT(p, MA_OWNED);
2119 if (!_SIG_VALID(sig))
2120 panic("%s(): invalid signal %d", __func__, sig);
2122 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2125 * IEEE Std 1003.1-2001: return success when killing a zombie.
2127 if (p->p_state == PRS_ZOMBIE) {
2128 if (ksi && (ksi->ksi_flags & KSI_INS))
2129 ksiginfo_tryfree(ksi);
2134 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2135 prop = sigprop(sig);
2138 td = sigtd(p, sig, prop);
2139 sigqueue = &p->p_sigqueue;
2141 sigqueue = &td->td_sigqueue;
2143 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2146 * If the signal is being ignored,
2147 * then we forget about it immediately.
2148 * (Note: we don't set SIGCONT in ps_sigignore,
2149 * and if it is set to SIG_IGN,
2150 * action will be SIG_DFL here.)
2152 mtx_lock(&ps->ps_mtx);
2153 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2154 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2156 mtx_unlock(&ps->ps_mtx);
2157 if (ksi && (ksi->ksi_flags & KSI_INS))
2158 ksiginfo_tryfree(ksi);
2161 if (SIGISMEMBER(td->td_sigmask, sig))
2163 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2167 if (SIGISMEMBER(ps->ps_sigintr, sig))
2171 mtx_unlock(&ps->ps_mtx);
2173 if (prop & SIGPROP_CONT)
2174 sigqueue_delete_stopmask_proc(p);
2175 else if (prop & SIGPROP_STOP) {
2177 * If sending a tty stop signal to a member of an orphaned
2178 * process group, discard the signal here if the action
2179 * is default; don't stop the process below if sleeping,
2180 * and don't clear any pending SIGCONT.
2182 if ((prop & SIGPROP_TTYSTOP) &&
2183 (p->p_pgrp->pg_jobc == 0) &&
2184 (action == SIG_DFL)) {
2185 if (ksi && (ksi->ksi_flags & KSI_INS))
2186 ksiginfo_tryfree(ksi);
2189 sigqueue_delete_proc(p, SIGCONT);
2190 if (p->p_flag & P_CONTINUED) {
2191 p->p_flag &= ~P_CONTINUED;
2192 PROC_LOCK(p->p_pptr);
2193 sigqueue_take(p->p_ksi);
2194 PROC_UNLOCK(p->p_pptr);
2198 ret = sigqueue_add(sigqueue, sig, ksi);
2203 * Defer further processing for signals which are held,
2204 * except that stopped processes must be continued by SIGCONT.
2206 if (action == SIG_HOLD &&
2207 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2210 /* SIGKILL: Remove procfs STOPEVENTs. */
2211 if (sig == SIGKILL) {
2212 /* from procfs_ioctl.c: PIOCBIC */
2214 /* from procfs_ioctl.c: PIOCCONT */
2219 * Some signals have a process-wide effect and a per-thread
2220 * component. Most processing occurs when the process next
2221 * tries to cross the user boundary, however there are some
2222 * times when processing needs to be done immediately, such as
2223 * waking up threads so that they can cross the user boundary.
2224 * We try to do the per-process part here.
2226 if (P_SHOULDSTOP(p)) {
2227 KASSERT(!(p->p_flag & P_WEXIT),
2228 ("signal to stopped but exiting process"));
2229 if (sig == SIGKILL) {
2231 * If traced process is already stopped,
2232 * then no further action is necessary.
2234 if (p->p_flag & P_TRACED)
2237 * SIGKILL sets process running.
2238 * It will die elsewhere.
2239 * All threads must be restarted.
2241 p->p_flag &= ~P_STOPPED_SIG;
2245 if (prop & SIGPROP_CONT) {
2247 * If traced process is already stopped,
2248 * then no further action is necessary.
2250 if (p->p_flag & P_TRACED)
2253 * If SIGCONT is default (or ignored), we continue the
2254 * process but don't leave the signal in sigqueue as
2255 * it has no further action. If SIGCONT is held, we
2256 * continue the process and leave the signal in
2257 * sigqueue. If the process catches SIGCONT, let it
2258 * handle the signal itself. If it isn't waiting on
2259 * an event, it goes back to run state.
2260 * Otherwise, process goes back to sleep state.
2262 p->p_flag &= ~P_STOPPED_SIG;
2264 if (p->p_numthreads == p->p_suspcount) {
2266 p->p_flag |= P_CONTINUED;
2267 p->p_xsig = SIGCONT;
2268 PROC_LOCK(p->p_pptr);
2269 childproc_continued(p);
2270 PROC_UNLOCK(p->p_pptr);
2273 if (action == SIG_DFL) {
2274 thread_unsuspend(p);
2276 sigqueue_delete(sigqueue, sig);
2279 if (action == SIG_CATCH) {
2281 * The process wants to catch it so it needs
2282 * to run at least one thread, but which one?
2288 * The signal is not ignored or caught.
2290 thread_unsuspend(p);
2295 if (prop & SIGPROP_STOP) {
2297 * If traced process is already stopped,
2298 * then no further action is necessary.
2300 if (p->p_flag & P_TRACED)
2303 * Already stopped, don't need to stop again
2304 * (If we did the shell could get confused).
2305 * Just make sure the signal STOP bit set.
2307 p->p_flag |= P_STOPPED_SIG;
2308 sigqueue_delete(sigqueue, sig);
2313 * All other kinds of signals:
2314 * If a thread is sleeping interruptibly, simulate a
2315 * wakeup so that when it is continued it will be made
2316 * runnable and can look at the signal. However, don't make
2317 * the PROCESS runnable, leave it stopped.
2318 * It may run a bit until it hits a thread_suspend_check().
2323 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2324 wakeup_swapper = sleepq_abort(td, intrval);
2331 * Mutexes are short lived. Threads waiting on them will
2332 * hit thread_suspend_check() soon.
2334 } else if (p->p_state == PRS_NORMAL) {
2335 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2336 tdsigwakeup(td, sig, action, intrval);
2340 MPASS(action == SIG_DFL);
2342 if (prop & SIGPROP_STOP) {
2343 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2345 p->p_flag |= P_STOPPED_SIG;
2348 wakeup_swapper = sig_suspend_threads(td, p, 1);
2349 if (p->p_numthreads == p->p_suspcount) {
2351 * only thread sending signal to another
2352 * process can reach here, if thread is sending
2353 * signal to its process, because thread does
2354 * not suspend itself here, p_numthreads
2355 * should never be equal to p_suspcount.
2359 sigqueue_delete_proc(p, p->p_xsig);
2367 /* Not in "NORMAL" state. discard the signal. */
2368 sigqueue_delete(sigqueue, sig);
2373 * The process is not stopped so we need to apply the signal to all the
2377 tdsigwakeup(td, sig, action, intrval);
2379 thread_unsuspend(p);
2382 /* If we jump here, proc slock should not be owned. */
2383 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2388 * The force of a signal has been directed against a single
2389 * thread. We need to see what we can do about knocking it
2390 * out of any sleep it may be in etc.
2393 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2395 struct proc *p = td->td_proc;
2400 PROC_LOCK_ASSERT(p, MA_OWNED);
2401 prop = sigprop(sig);
2406 * Bring the priority of a thread up if we want it to get
2407 * killed in this lifetime. Be careful to avoid bumping the
2408 * priority of the idle thread, since we still allow to signal
2411 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2412 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2413 sched_prio(td, PUSER);
2414 if (TD_ON_SLEEPQ(td)) {
2416 * If thread is sleeping uninterruptibly
2417 * we can't interrupt the sleep... the signal will
2418 * be noticed when the process returns through
2419 * trap() or syscall().
2421 if ((td->td_flags & TDF_SINTR) == 0)
2424 * If SIGCONT is default (or ignored) and process is
2425 * asleep, we are finished; the process should not
2428 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2431 sigqueue_delete(&p->p_sigqueue, sig);
2433 * It may be on either list in this state.
2434 * Remove from both for now.
2436 sigqueue_delete(&td->td_sigqueue, sig);
2441 * Don't awaken a sleeping thread for SIGSTOP if the
2442 * STOP signal is deferred.
2444 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2445 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2449 * Give low priority threads a better chance to run.
2451 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2452 sched_prio(td, PUSER);
2454 wakeup_swapper = sleepq_abort(td, intrval);
2457 * Other states do nothing with the signal immediately,
2458 * other than kicking ourselves if we are running.
2459 * It will either never be noticed, or noticed very soon.
2462 if (TD_IS_RUNNING(td) && td != curthread)
2474 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2479 PROC_LOCK_ASSERT(p, MA_OWNED);
2480 PROC_SLOCK_ASSERT(p, MA_OWNED);
2481 MPASS(sending || td == curthread);
2484 FOREACH_THREAD_IN_PROC(p, td2) {
2486 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2487 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2488 (td2->td_flags & TDF_SINTR)) {
2489 if (td2->td_flags & TDF_SBDRY) {
2491 * Once a thread is asleep with
2492 * TDF_SBDRY and without TDF_SERESTART
2493 * or TDF_SEINTR set, it should never
2494 * become suspended due to this check.
2496 KASSERT(!TD_IS_SUSPENDED(td2),
2497 ("thread with deferred stops suspended"));
2498 if (TD_SBDRY_INTR(td2))
2499 wakeup_swapper |= sleepq_abort(td2,
2500 TD_SBDRY_ERRNO(td2));
2501 } else if (!TD_IS_SUSPENDED(td2)) {
2502 thread_suspend_one(td2);
2504 } else if (!TD_IS_SUSPENDED(td2)) {
2505 if (sending || td != td2)
2506 td2->td_flags |= TDF_ASTPENDING;
2508 if (TD_IS_RUNNING(td2) && td2 != td)
2509 forward_signal(td2);
2514 return (wakeup_swapper);
2518 * Stop the process for an event deemed interesting to the debugger. If si is
2519 * non-NULL, this is a signal exchange; the new signal requested by the
2520 * debugger will be returned for handling. If si is NULL, this is some other
2521 * type of interesting event. The debugger may request a signal be delivered in
2522 * that case as well, however it will be deferred until it can be handled.
2525 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2527 struct proc *p = td->td_proc;
2532 PROC_LOCK_ASSERT(p, MA_OWNED);
2533 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2534 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2535 &p->p_mtx.lock_object, "Stopping for traced signal");
2539 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2540 td->td_dbgflags |= TDB_XSIG;
2541 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2542 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2544 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2547 * Ensure that, if we've been PT_KILLed, the
2548 * exit status reflects that. Another thread
2549 * may also be in ptracestop(), having just
2550 * received the SIGKILL, but this thread was
2551 * unsuspended first.
2553 td->td_dbgflags &= ~TDB_XSIG;
2554 td->td_xsig = SIGKILL;
2558 if (p->p_flag & P_SINGLE_EXIT &&
2559 !(td->td_dbgflags & TDB_EXIT)) {
2561 * Ignore ptrace stops except for thread exit
2562 * events when the process exits.
2564 td->td_dbgflags &= ~TDB_XSIG;
2570 * Make wait(2) work. Ensure that right after the
2571 * attach, the thread which was decided to become the
2572 * leader of attach gets reported to the waiter.
2573 * Otherwise, just avoid overwriting another thread's
2574 * assignment to p_xthread. If another thread has
2575 * already set p_xthread, the current thread will get
2576 * a chance to report itself upon the next iteration.
2578 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2579 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2580 p->p_xthread == NULL)) {
2583 td->td_dbgflags &= ~TDB_FSTP;
2584 p->p_flag2 &= ~P2_PTRACE_FSTP;
2585 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2586 sig_suspend_threads(td, p, 0);
2588 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2589 td->td_dbgflags &= ~TDB_STOPATFORK;
2590 cv_broadcast(&p->p_dbgwait);
2593 thread_suspend_switch(td, p);
2594 if (p->p_xthread == td)
2595 p->p_xthread = NULL;
2596 if (!(p->p_flag & P_TRACED))
2598 if (td->td_dbgflags & TDB_SUSPEND) {
2599 if (p->p_flag & P_SINGLE_EXIT)
2607 if (si != NULL && sig == td->td_xsig) {
2608 /* Parent wants us to take the original signal unchanged. */
2609 si->ksi_flags |= KSI_HEAD;
2610 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2612 } else if (td->td_xsig != 0) {
2614 * If parent wants us to take a new signal, then it will leave
2615 * it in td->td_xsig; otherwise we just look for signals again.
2617 ksiginfo_init(&ksi);
2618 ksi.ksi_signo = td->td_xsig;
2619 ksi.ksi_flags |= KSI_PTRACE;
2620 prop = sigprop(td->td_xsig);
2621 td2 = sigtd(p, td->td_xsig, prop);
2622 tdsendsignal(p, td2, td->td_xsig, &ksi);
2627 return (td->td_xsig);
2631 reschedule_signals(struct proc *p, sigset_t block, int flags)
2637 PROC_LOCK_ASSERT(p, MA_OWNED);
2639 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2640 MA_OWNED : MA_NOTOWNED);
2641 if (SIGISEMPTY(p->p_siglist))
2643 SIGSETAND(block, p->p_siglist);
2644 while ((sig = sig_ffs(&block)) != 0) {
2645 SIGDELSET(block, sig);
2646 td = sigtd(p, sig, 0);
2648 if (!(flags & SIGPROCMASK_PS_LOCKED))
2649 mtx_lock(&ps->ps_mtx);
2650 if (p->p_flag & P_TRACED ||
2651 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2652 !SIGISMEMBER(td->td_sigmask, sig)))
2653 tdsigwakeup(td, sig, SIG_CATCH,
2654 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2656 if (!(flags & SIGPROCMASK_PS_LOCKED))
2657 mtx_unlock(&ps->ps_mtx);
2662 tdsigcleanup(struct thread *td)
2668 PROC_LOCK_ASSERT(p, MA_OWNED);
2670 sigqueue_flush(&td->td_sigqueue);
2671 if (p->p_numthreads == 1)
2675 * Since we cannot handle signals, notify signal post code
2676 * about this by filling the sigmask.
2678 * Also, if needed, wake up thread(s) that do not block the
2679 * same signals as the exiting thread, since the thread might
2680 * have been selected for delivery and woken up.
2682 SIGFILLSET(unblocked);
2683 SIGSETNAND(unblocked, td->td_sigmask);
2684 SIGFILLSET(td->td_sigmask);
2685 reschedule_signals(p, unblocked, 0);
2690 sigdeferstop_curr_flags(int cflags)
2693 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2694 (cflags & TDF_SBDRY) != 0);
2695 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2699 * Defer the delivery of SIGSTOP for the current thread, according to
2700 * the requested mode. Returns previous flags, which must be restored
2701 * by sigallowstop().
2703 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2704 * cleared by the current thread, which allow the lock-less read-only
2708 sigdeferstop_impl(int mode)
2714 cflags = sigdeferstop_curr_flags(td->td_flags);
2716 case SIGDEFERSTOP_NOP:
2719 case SIGDEFERSTOP_OFF:
2722 case SIGDEFERSTOP_SILENT:
2723 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2725 case SIGDEFERSTOP_EINTR:
2726 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2728 case SIGDEFERSTOP_ERESTART:
2729 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2732 panic("sigdeferstop: invalid mode %x", mode);
2735 if (cflags == nflags)
2736 return (SIGDEFERSTOP_VAL_NCHG);
2738 td->td_flags = (td->td_flags & ~cflags) | nflags;
2744 * Restores the STOP handling mode, typically permitting the delivery
2745 * of SIGSTOP for the current thread. This does not immediately
2746 * suspend if a stop was posted. Instead, the thread will suspend
2747 * either via ast() or a subsequent interruptible sleep.
2750 sigallowstop_impl(int prev)
2755 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2756 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2757 ("sigallowstop: incorrect previous mode %x", prev));
2759 cflags = sigdeferstop_curr_flags(td->td_flags);
2760 if (cflags != prev) {
2762 td->td_flags = (td->td_flags & ~cflags) | prev;
2768 * If the current process has received a signal (should be caught or cause
2769 * termination, should interrupt current syscall), return the signal number.
2770 * Stop signals with default action are processed immediately, then cleared;
2771 * they aren't returned. This is checked after each entry to the system for
2772 * a syscall or trap (though this can usually be done without calling issignal
2773 * by checking the pending signal masks in cursig.) The normal call
2776 * while (sig = cursig(curthread))
2780 issignal(struct thread *td)
2784 struct sigqueue *queue;
2785 sigset_t sigpending;
2787 int prop, sig, traced;
2791 mtx_assert(&ps->ps_mtx, MA_OWNED);
2792 PROC_LOCK_ASSERT(p, MA_OWNED);
2794 traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2796 sigpending = td->td_sigqueue.sq_signals;
2797 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2798 SIGSETNAND(sigpending, td->td_sigmask);
2800 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
2801 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2802 SIG_STOPSIGMASK(sigpending);
2803 if (SIGISEMPTY(sigpending)) /* no signal to send */
2805 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2806 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2807 SIGISMEMBER(sigpending, SIGSTOP)) {
2809 * If debugger just attached, always consume
2810 * SIGSTOP from ptrace(PT_ATTACH) first, to
2811 * execute the debugger attach ritual in
2815 td->td_dbgflags |= TDB_FSTP;
2817 sig = sig_ffs(&sigpending);
2820 if (p->p_stops & S_SIG) {
2821 mtx_unlock(&ps->ps_mtx);
2822 stopevent(p, S_SIG, sig);
2823 mtx_lock(&ps->ps_mtx);
2827 * We should see pending but ignored signals
2828 * only if P_TRACED was on when they were posted.
2830 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2831 sigqueue_delete(&td->td_sigqueue, sig);
2832 sigqueue_delete(&p->p_sigqueue, sig);
2835 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2837 * If traced, always stop.
2838 * Remove old signal from queue before the stop.
2839 * XXX shrug off debugger, it causes siginfo to
2842 queue = &td->td_sigqueue;
2843 ksiginfo_init(&ksi);
2844 if (sigqueue_get(queue, sig, &ksi) == 0) {
2845 queue = &p->p_sigqueue;
2846 sigqueue_get(queue, sig, &ksi);
2848 td->td_si = ksi.ksi_info;
2850 mtx_unlock(&ps->ps_mtx);
2851 sig = ptracestop(td, sig, &ksi);
2852 mtx_lock(&ps->ps_mtx);
2855 * Keep looking if the debugger discarded or
2856 * replaced the signal.
2862 * If the signal became masked, re-queue it.
2864 if (SIGISMEMBER(td->td_sigmask, sig)) {
2865 ksi.ksi_flags |= KSI_HEAD;
2866 sigqueue_add(&p->p_sigqueue, sig, &ksi);
2871 * If the traced bit got turned off, requeue
2872 * the signal and go back up to the top to
2873 * rescan signals. This ensures that p_sig*
2874 * and p_sigact are consistent.
2876 if ((p->p_flag & P_TRACED) == 0) {
2877 ksi.ksi_flags |= KSI_HEAD;
2878 sigqueue_add(queue, sig, &ksi);
2883 prop = sigprop(sig);
2886 * Decide whether the signal should be returned.
2887 * Return the signal's number, or fall through
2888 * to clear it from the pending mask.
2890 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2892 case (intptr_t)SIG_DFL:
2894 * Don't take default actions on system processes.
2896 if (p->p_pid <= 1) {
2899 * Are you sure you want to ignore SIGSEGV
2902 printf("Process (pid %lu) got signal %d\n",
2903 (u_long)p->p_pid, sig);
2905 break; /* == ignore */
2908 * If there is a pending stop signal to process with
2909 * default action, stop here, then clear the signal.
2910 * Traced or exiting processes should ignore stops.
2911 * Additionally, a member of an orphaned process group
2912 * should ignore tty stops.
2914 if (prop & SIGPROP_STOP) {
2916 (P_TRACED | P_WEXIT | P_SINGLE_EXIT) ||
2917 (p->p_pgrp->pg_jobc == 0 &&
2918 prop & SIGPROP_TTYSTOP))
2919 break; /* == ignore */
2920 if (TD_SBDRY_INTR(td)) {
2921 KASSERT((td->td_flags & TDF_SBDRY) != 0,
2922 ("lost TDF_SBDRY"));
2925 mtx_unlock(&ps->ps_mtx);
2926 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2927 &p->p_mtx.lock_object, "Catching SIGSTOP");
2928 sigqueue_delete(&td->td_sigqueue, sig);
2929 sigqueue_delete(&p->p_sigqueue, sig);
2930 p->p_flag |= P_STOPPED_SIG;
2933 sig_suspend_threads(td, p, 0);
2934 thread_suspend_switch(td, p);
2936 mtx_lock(&ps->ps_mtx);
2938 } else if (prop & SIGPROP_IGNORE) {
2940 * Except for SIGCONT, shouldn't get here.
2941 * Default action is to ignore; drop it.
2943 break; /* == ignore */
2948 case (intptr_t)SIG_IGN:
2950 * Masking above should prevent us ever trying
2951 * to take action on an ignored signal other
2952 * than SIGCONT, unless process is traced.
2954 if ((prop & SIGPROP_CONT) == 0 &&
2955 (p->p_flag & P_TRACED) == 0)
2956 printf("issignal\n");
2957 break; /* == ignore */
2961 * This signal has an action, let
2962 * postsig() process it.
2966 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2967 sigqueue_delete(&p->p_sigqueue, sig);
2974 thread_stopped(struct proc *p)
2978 PROC_LOCK_ASSERT(p, MA_OWNED);
2979 PROC_SLOCK_ASSERT(p, MA_OWNED);
2983 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2985 p->p_flag &= ~P_WAITED;
2986 PROC_LOCK(p->p_pptr);
2987 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2988 CLD_TRAPPED : CLD_STOPPED);
2989 PROC_UNLOCK(p->p_pptr);
2995 * Take the action for the specified signal
2996 * from the current set of pending signals.
3006 sigset_t returnmask;
3008 KASSERT(sig != 0, ("postsig"));
3012 PROC_LOCK_ASSERT(p, MA_OWNED);
3014 mtx_assert(&ps->ps_mtx, MA_OWNED);
3015 ksiginfo_init(&ksi);
3016 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3017 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3019 ksi.ksi_signo = sig;
3020 if (ksi.ksi_code == SI_TIMER)
3021 itimer_accept(p, ksi.ksi_timerid, &ksi);
3022 action = ps->ps_sigact[_SIG_IDX(sig)];
3024 if (KTRPOINT(td, KTR_PSIG))
3025 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3026 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3028 if ((p->p_stops & S_SIG) != 0) {
3029 mtx_unlock(&ps->ps_mtx);
3030 stopevent(p, S_SIG, sig);
3031 mtx_lock(&ps->ps_mtx);
3034 if (action == SIG_DFL) {
3036 * Default action, where the default is to kill
3037 * the process. (Other cases were ignored above.)
3039 mtx_unlock(&ps->ps_mtx);
3040 proc_td_siginfo_capture(td, &ksi.ksi_info);
3045 * If we get here, the signal must be caught.
3047 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3048 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3049 ("postsig action: blocked sig %d", sig));
3052 * Set the new mask value and also defer further
3053 * occurrences of this signal.
3055 * Special case: user has done a sigsuspend. Here the
3056 * current mask is not of interest, but rather the
3057 * mask from before the sigsuspend is what we want
3058 * restored after the signal processing is completed.
3060 if (td->td_pflags & TDP_OLDMASK) {
3061 returnmask = td->td_oldsigmask;
3062 td->td_pflags &= ~TDP_OLDMASK;
3064 returnmask = td->td_sigmask;
3066 if (p->p_sig == sig) {
3070 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3071 postsig_done(sig, td, ps);
3077 * Kill the current process for stated reason.
3080 killproc(struct proc *p, char *why)
3083 PROC_LOCK_ASSERT(p, MA_OWNED);
3084 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3086 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
3087 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
3088 p->p_flag |= P_WKILLED;
3089 kern_psignal(p, SIGKILL);
3093 * Force the current process to exit with the specified signal, dumping core
3094 * if appropriate. We bypass the normal tests for masked and caught signals,
3095 * allowing unrecoverable failures to terminate the process without changing
3096 * signal state. Mark the accounting record with the signal termination.
3097 * If dumping core, save the signal number for the debugger. Calls exit and
3101 sigexit(struct thread *td, int sig)
3103 struct proc *p = td->td_proc;
3105 PROC_LOCK_ASSERT(p, MA_OWNED);
3106 p->p_acflag |= AXSIG;
3108 * We must be single-threading to generate a core dump. This
3109 * ensures that the registers in the core file are up-to-date.
3110 * Also, the ELF dump handler assumes that the thread list doesn't
3111 * change out from under it.
3113 * XXX If another thread attempts to single-thread before us
3114 * (e.g. via fork()), we won't get a dump at all.
3116 if ((sigprop(sig) & SIGPROP_CORE) &&
3117 thread_single(p, SINGLE_NO_EXIT) == 0) {
3120 * Log signals which would cause core dumps
3121 * (Log as LOG_INFO to appease those who don't want
3123 * XXX : Todo, as well as euid, write out ruid too
3124 * Note that coredump() drops proc lock.
3126 if (coredump(td) == 0)
3128 if (kern_logsigexit)
3130 "pid %d (%s), uid %d: exited on signal %d%s\n",
3131 p->p_pid, p->p_comm,
3132 td->td_ucred ? td->td_ucred->cr_uid : -1,
3134 sig & WCOREFLAG ? " (core dumped)" : "");
3142 * Send queued SIGCHLD to parent when child process's state
3146 sigparent(struct proc *p, int reason, int status)
3148 PROC_LOCK_ASSERT(p, MA_OWNED);
3149 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3151 if (p->p_ksi != NULL) {
3152 p->p_ksi->ksi_signo = SIGCHLD;
3153 p->p_ksi->ksi_code = reason;
3154 p->p_ksi->ksi_status = status;
3155 p->p_ksi->ksi_pid = p->p_pid;
3156 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3157 if (KSI_ONQ(p->p_ksi))
3160 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3164 childproc_jobstate(struct proc *p, int reason, int sig)
3168 PROC_LOCK_ASSERT(p, MA_OWNED);
3169 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3172 * Wake up parent sleeping in kern_wait(), also send
3173 * SIGCHLD to parent, but SIGCHLD does not guarantee
3174 * that parent will awake, because parent may masked
3177 p->p_pptr->p_flag |= P_STATCHILD;
3180 ps = p->p_pptr->p_sigacts;
3181 mtx_lock(&ps->ps_mtx);
3182 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3183 mtx_unlock(&ps->ps_mtx);
3184 sigparent(p, reason, sig);
3186 mtx_unlock(&ps->ps_mtx);
3190 childproc_stopped(struct proc *p, int reason)
3193 childproc_jobstate(p, reason, p->p_xsig);
3197 childproc_continued(struct proc *p)
3199 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3203 childproc_exited(struct proc *p)
3207 if (WCOREDUMP(p->p_xsig)) {
3208 reason = CLD_DUMPED;
3209 status = WTERMSIG(p->p_xsig);
3210 } else if (WIFSIGNALED(p->p_xsig)) {
3211 reason = CLD_KILLED;
3212 status = WTERMSIG(p->p_xsig);
3214 reason = CLD_EXITED;
3215 status = p->p_xexit;
3218 * XXX avoid calling wakeup(p->p_pptr), the work is
3221 sigparent(p, reason, status);
3225 * We only have 1 character for the core count in the format
3226 * string, so the range will be 0-9
3228 #define MAX_NUM_CORE_FILES 10
3229 #ifndef NUM_CORE_FILES
3230 #define NUM_CORE_FILES 5
3232 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3233 static int num_cores = NUM_CORE_FILES;
3236 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3241 new_val = num_cores;
3242 error = sysctl_handle_int(oidp, &new_val, 0, req);
3243 if (error != 0 || req->newptr == NULL)
3245 if (new_val > MAX_NUM_CORE_FILES)
3246 new_val = MAX_NUM_CORE_FILES;
3249 num_cores = new_val;
3252 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3253 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3255 #define GZIP_SUFFIX ".gz"
3256 #define ZSTD_SUFFIX ".zst"
3258 int compress_user_cores = 0;
3261 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3265 val = compress_user_cores;
3266 error = sysctl_handle_int(oidp, &val, 0, req);
3267 if (error != 0 || req->newptr == NULL)
3269 if (val != 0 && !compressor_avail(val))
3271 compress_user_cores = val;
3274 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores, CTLTYPE_INT | CTLFLAG_RWTUN,
3275 0, sizeof(int), sysctl_compress_user_cores, "I",
3276 "Enable compression of user corefiles ("
3277 __XSTRING(COMPRESS_GZIP) " = gzip, "
3278 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3280 int compress_user_cores_level = 6;
3281 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3282 &compress_user_cores_level, 0,
3283 "Corefile compression level");
3286 * Protect the access to corefilename[] by allproc_lock.
3288 #define corefilename_lock allproc_lock
3290 static char corefilename[MAXPATHLEN] = {"%N.core"};
3291 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3294 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3298 sx_xlock(&corefilename_lock);
3299 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3301 sx_xunlock(&corefilename_lock);
3305 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3306 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3307 "Process corefile name format string");
3310 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3311 * Expand the name described in corefilename, using name, uid, and pid
3312 * and open/create core file.
3313 * corefilename is a printf-like string, with three format specifiers:
3314 * %N name of process ("name")
3315 * %P process id (pid)
3317 * For example, "%N.core" is the default; they can be disabled completely
3318 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3319 * This is controlled by the sysctl variable kern.corefile (see above).
3322 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3323 int compress, struct vnode **vpp, char **namep)
3325 struct nameidata nd;
3328 char *hostname, *name;
3329 int indexpos, i, error, cmode, flags, oflags;
3332 format = corefilename;
3333 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3335 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3336 sx_slock(&corefilename_lock);
3337 for (i = 0; format[i] != '\0'; i++) {
3338 switch (format[i]) {
3339 case '%': /* Format character */
3341 switch (format[i]) {
3343 sbuf_putc(&sb, '%');
3345 case 'H': /* hostname */
3346 if (hostname == NULL) {
3347 hostname = malloc(MAXHOSTNAMELEN,
3350 getcredhostname(td->td_ucred, hostname,
3352 sbuf_printf(&sb, "%s", hostname);
3354 case 'I': /* autoincrementing index */
3355 sbuf_printf(&sb, "0");
3356 indexpos = sbuf_len(&sb) - 1;
3358 case 'N': /* process name */
3359 sbuf_printf(&sb, "%s", comm);
3361 case 'P': /* process id */
3362 sbuf_printf(&sb, "%u", pid);
3364 case 'U': /* user id */
3365 sbuf_printf(&sb, "%u", uid);
3369 "Unknown format character %c in "
3370 "corename `%s'\n", format[i], format);
3375 sbuf_putc(&sb, format[i]);
3379 sx_sunlock(&corefilename_lock);
3380 free(hostname, M_TEMP);
3381 if (compress == COMPRESS_GZIP)
3382 sbuf_printf(&sb, GZIP_SUFFIX);
3383 else if (compress == COMPRESS_ZSTD)
3384 sbuf_printf(&sb, ZSTD_SUFFIX);
3385 if (sbuf_error(&sb) != 0) {
3386 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3387 "long\n", (long)pid, comm, (u_long)uid);
3395 cmode = S_IRUSR | S_IWUSR;
3396 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3397 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3400 * If the core format has a %I in it, then we need to check
3401 * for existing corefiles before returning a name.
3402 * To do this we iterate over 0..num_cores to find a
3403 * non-existing core file name to use.
3405 if (indexpos != -1) {
3406 for (i = 0; i < num_cores; i++) {
3407 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3408 name[indexpos] = '0' + i;
3409 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3410 error = vn_open_cred(&nd, &flags, cmode, oflags,
3411 td->td_ucred, NULL);
3413 if (error == EEXIST)
3416 "pid %d (%s), uid (%u): Path `%s' failed "
3417 "on initial open test, error = %d\n",
3418 pid, comm, uid, name, error);
3424 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3425 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3426 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3430 audit_proc_coredump(td, name, error);
3435 NDFREE(&nd, NDF_ONLY_PNBUF);
3442 coredump_sanitise_path(const char *path)
3447 * Only send a subset of ASCII to devd(8) because it
3448 * might pass these strings to sh -c.
3450 for (i = 0; path[i]; i++)
3451 if (!(isalpha(path[i]) || isdigit(path[i])) &&
3452 path[i] != '/' && path[i] != '.' &&
3460 * Dump a process' core. The main routine does some
3461 * policy checking, and creates the name of the coredump;
3462 * then it passes on a vnode and a size limit to the process-specific
3463 * coredump routine if there is one; if there _is not_ one, it returns
3464 * ENOSYS; otherwise it returns the error from the process-specific routine.
3468 coredump(struct thread *td)
3470 struct proc *p = td->td_proc;
3471 struct ucred *cred = td->td_ucred;
3475 int error, error1, locked;
3476 char *name; /* name of corefile */
3480 char *fullpath, *freepath = NULL;
3482 static const char comm_name[] = "comm=";
3483 static const char core_name[] = "core=";
3485 PROC_LOCK_ASSERT(p, MA_OWNED);
3486 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3487 _STOPEVENT(p, S_CORE, 0);
3489 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3490 (p->p_flag2 & P2_NOTRACE) != 0) {
3496 * Note that the bulk of limit checking is done after
3497 * the corefile is created. The exception is if the limit
3498 * for corefiles is 0, in which case we don't bother
3499 * creating the corefile at all. This layout means that
3500 * a corefile is truncated instead of not being created,
3501 * if it is larger than the limit.
3503 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3504 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3510 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3511 compress_user_cores, &vp, &name);
3516 * Don't dump to non-regular files or files with links.
3517 * Do not dump into system files.
3519 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3520 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0) {
3528 /* Postpone other writers, including core dumps of other processes. */
3529 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3531 lf.l_whence = SEEK_SET;
3534 lf.l_type = F_WRLCK;
3535 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3539 if (set_core_nodump_flag)
3540 vattr.va_flags = UF_NODUMP;
3541 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3542 VOP_SETATTR(vp, &vattr, cred);
3545 p->p_acflag |= ACORE;
3548 if (p->p_sysent->sv_coredump != NULL) {
3549 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3555 lf.l_type = F_UNLCK;
3556 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3558 vn_rangelock_unlock(vp, rl_cookie);
3561 * Notify the userland helper that a process triggered a core dump.
3562 * This allows the helper to run an automated debugging session.
3564 if (error != 0 || coredump_devctl == 0)
3566 len = MAXPATHLEN * 2 + sizeof(comm_name) - 1 +
3567 sizeof(' ') + sizeof(core_name) - 1;
3568 data = malloc(len, M_TEMP, M_WAITOK);
3569 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3571 if (!coredump_sanitise_path(fullpath))
3573 snprintf(data, len, "%s%s ", comm_name, fullpath);
3574 free(freepath, M_TEMP);
3576 if (vn_fullpath_global(td, vp, &fullpath, &freepath) != 0)
3578 if (!coredump_sanitise_path(fullpath))
3580 strlcat(data, core_name, len);
3581 strlcat(data, fullpath, len);
3582 devctl_notify("kernel", "signal", "coredump", data);
3584 error1 = vn_close(vp, FWRITE, cred, td);
3588 audit_proc_coredump(td, name, error);
3590 free(freepath, M_TEMP);
3597 * Nonexistent system call-- signal process (may want to handle it). Flag
3598 * error in case process won't see signal immediately (blocked or ignored).
3600 #ifndef _SYS_SYSPROTO_H_
3607 nosys(struct thread *td, struct nosys_args *args)
3614 tdsignal(td, SIGSYS);
3616 if (kern_lognosys == 1 || kern_lognosys == 3) {
3617 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3620 if (kern_lognosys == 2 || kern_lognosys == 3) {
3621 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3628 * Send a SIGIO or SIGURG signal to a process or process group using stored
3629 * credentials rather than those of the current process.
3632 pgsigio(struct sigio **sigiop, int sig, int checkctty)
3635 struct sigio *sigio;
3637 ksiginfo_init(&ksi);
3638 ksi.ksi_signo = sig;
3639 ksi.ksi_code = SI_KERNEL;
3643 if (sigio == NULL) {
3647 if (sigio->sio_pgid > 0) {
3648 PROC_LOCK(sigio->sio_proc);
3649 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3650 kern_psignal(sigio->sio_proc, sig);
3651 PROC_UNLOCK(sigio->sio_proc);
3652 } else if (sigio->sio_pgid < 0) {
3655 PGRP_LOCK(sigio->sio_pgrp);
3656 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3658 if (p->p_state == PRS_NORMAL &&
3659 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3660 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3661 kern_psignal(p, sig);
3664 PGRP_UNLOCK(sigio->sio_pgrp);
3670 filt_sigattach(struct knote *kn)
3672 struct proc *p = curproc;
3674 kn->kn_ptr.p_proc = p;
3675 kn->kn_flags |= EV_CLEAR; /* automatically set */
3677 knlist_add(p->p_klist, kn, 0);
3683 filt_sigdetach(struct knote *kn)
3685 struct proc *p = kn->kn_ptr.p_proc;
3687 knlist_remove(p->p_klist, kn, 0);
3691 * signal knotes are shared with proc knotes, so we apply a mask to
3692 * the hint in order to differentiate them from process hints. This
3693 * could be avoided by using a signal-specific knote list, but probably
3694 * isn't worth the trouble.
3697 filt_signal(struct knote *kn, long hint)
3700 if (hint & NOTE_SIGNAL) {
3701 hint &= ~NOTE_SIGNAL;
3703 if (kn->kn_id == hint)
3706 return (kn->kn_data != 0);
3714 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3715 refcount_init(&ps->ps_refcnt, 1);
3716 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3721 sigacts_free(struct sigacts *ps)
3724 if (refcount_release(&ps->ps_refcnt) == 0)
3726 mtx_destroy(&ps->ps_mtx);
3727 free(ps, M_SUBPROC);
3731 sigacts_hold(struct sigacts *ps)
3734 refcount_acquire(&ps->ps_refcnt);
3739 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3742 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3743 mtx_lock(&src->ps_mtx);
3744 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3745 mtx_unlock(&src->ps_mtx);
3749 sigacts_shared(struct sigacts *ps)
3752 return (ps->ps_refcnt > 1);