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
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
12 * Redistribution and use in source and binary forms, with or without
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
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
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
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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_ktrace.h"
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
50 #include <sys/capsicum.h>
51 #include <sys/compressor.h>
52 #include <sys/condvar.h>
53 #include <sys/devctl.h>
54 #include <sys/event.h>
55 #include <sys/fcntl.h>
56 #include <sys/imgact.h>
57 #include <sys/kernel.h>
59 #include <sys/ktrace.h>
60 #include <sys/limits.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/ptrace.h>
69 #include <sys/posix4.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 void reschedule_signals(struct proc *p, sigset_t block, int flags);
111 static int sigprop(int sig);
112 static void tdsigwakeup(struct thread *, int, sig_t, int);
113 static int sig_suspend_threads(struct thread *, struct proc *, int);
114 static int filt_sigattach(struct knote *kn);
115 static void filt_sigdetach(struct knote *kn);
116 static int filt_signal(struct knote *kn, long hint);
117 static struct thread *sigtd(struct proc *p, int sig, bool fast_sigblock);
118 static void sigqueue_start(void);
120 static uma_zone_t ksiginfo_zone = NULL;
121 struct filterops sig_filtops = {
123 .f_attach = filt_sigattach,
124 .f_detach = filt_sigdetach,
125 .f_event = filt_signal,
128 static int kern_logsigexit = 1;
129 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
131 "Log processes quitting on abnormal signals to syslog(3)");
133 static int kern_forcesigexit = 1;
134 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
135 &kern_forcesigexit, 0, "Force trap signal to be handled");
137 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
138 "POSIX real time signal");
140 static int max_pending_per_proc = 128;
141 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
142 &max_pending_per_proc, 0, "Max pending signals per proc");
144 static int preallocate_siginfo = 1024;
145 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
146 &preallocate_siginfo, 0, "Preallocated signal memory size");
148 static int signal_overflow = 0;
149 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
150 &signal_overflow, 0, "Number of signals overflew");
152 static int signal_alloc_fail = 0;
153 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
154 &signal_alloc_fail, 0, "signals failed to be allocated");
156 static int kern_lognosys = 0;
157 SYSCTL_INT(_kern, OID_AUTO, lognosys, CTLFLAG_RWTUN, &kern_lognosys, 0,
158 "Log invalid syscalls");
160 __read_frequently bool sigfastblock_fetch_always = false;
161 SYSCTL_BOOL(_kern, OID_AUTO, sigfastblock_fetch_always, CTLFLAG_RWTUN,
162 &sigfastblock_fetch_always, 0,
163 "Fetch sigfastblock word on each syscall entry for proper "
164 "blocking semantic");
166 static bool kern_sig_discard_ign = true;
167 SYSCTL_BOOL(_kern, OID_AUTO, sig_discard_ign, CTLFLAG_RWTUN,
168 &kern_sig_discard_ign, 0,
169 "Discard ignored signals on delivery, otherwise queue them to "
172 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
175 * Policy -- Can ucred cr1 send SIGIO to process cr2?
176 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
177 * in the right situations.
179 #define CANSIGIO(cr1, cr2) \
180 ((cr1)->cr_uid == 0 || \
181 (cr1)->cr_ruid == (cr2)->cr_ruid || \
182 (cr1)->cr_uid == (cr2)->cr_ruid || \
183 (cr1)->cr_ruid == (cr2)->cr_uid || \
184 (cr1)->cr_uid == (cr2)->cr_uid)
186 static int sugid_coredump;
187 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
188 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
190 static int capmode_coredump;
191 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
192 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
194 static int do_coredump = 1;
195 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
196 &do_coredump, 0, "Enable/Disable coredumps");
198 static int set_core_nodump_flag = 0;
199 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
200 0, "Enable setting the NODUMP flag on coredump files");
202 static int coredump_devctl = 0;
203 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
204 0, "Generate a devctl notification when processes coredump");
207 * Signal properties and actions.
208 * The array below categorizes the signals and their default actions
209 * according to the following properties:
211 #define SIGPROP_KILL 0x01 /* terminates process by default */
212 #define SIGPROP_CORE 0x02 /* ditto and coredumps */
213 #define SIGPROP_STOP 0x04 /* suspend process */
214 #define SIGPROP_TTYSTOP 0x08 /* ditto, from tty */
215 #define SIGPROP_IGNORE 0x10 /* ignore by default */
216 #define SIGPROP_CONT 0x20 /* continue if suspended */
218 static int sigproptbl[NSIG] = {
219 [SIGHUP] = SIGPROP_KILL,
220 [SIGINT] = SIGPROP_KILL,
221 [SIGQUIT] = SIGPROP_KILL | SIGPROP_CORE,
222 [SIGILL] = SIGPROP_KILL | SIGPROP_CORE,
223 [SIGTRAP] = SIGPROP_KILL | SIGPROP_CORE,
224 [SIGABRT] = SIGPROP_KILL | SIGPROP_CORE,
225 [SIGEMT] = SIGPROP_KILL | SIGPROP_CORE,
226 [SIGFPE] = SIGPROP_KILL | SIGPROP_CORE,
227 [SIGKILL] = SIGPROP_KILL,
228 [SIGBUS] = SIGPROP_KILL | SIGPROP_CORE,
229 [SIGSEGV] = SIGPROP_KILL | SIGPROP_CORE,
230 [SIGSYS] = SIGPROP_KILL | SIGPROP_CORE,
231 [SIGPIPE] = SIGPROP_KILL,
232 [SIGALRM] = SIGPROP_KILL,
233 [SIGTERM] = SIGPROP_KILL,
234 [SIGURG] = SIGPROP_IGNORE,
235 [SIGSTOP] = SIGPROP_STOP,
236 [SIGTSTP] = SIGPROP_STOP | SIGPROP_TTYSTOP,
237 [SIGCONT] = SIGPROP_IGNORE | SIGPROP_CONT,
238 [SIGCHLD] = SIGPROP_IGNORE,
239 [SIGTTIN] = SIGPROP_STOP | SIGPROP_TTYSTOP,
240 [SIGTTOU] = SIGPROP_STOP | SIGPROP_TTYSTOP,
241 [SIGIO] = SIGPROP_IGNORE,
242 [SIGXCPU] = SIGPROP_KILL,
243 [SIGXFSZ] = SIGPROP_KILL,
244 [SIGVTALRM] = SIGPROP_KILL,
245 [SIGPROF] = SIGPROP_KILL,
246 [SIGWINCH] = SIGPROP_IGNORE,
247 [SIGINFO] = SIGPROP_IGNORE,
248 [SIGUSR1] = SIGPROP_KILL,
249 [SIGUSR2] = SIGPROP_KILL,
252 #define _SIG_FOREACH_ADVANCE(i, set) ({ \
256 int __sig = ffs(__bits); \
257 __bits &= ~(1u << (__sig - 1)); \
258 sig = __i * sizeof((set)->__bits[0]) * NBBY + __sig; \
262 if (++__i == _SIG_WORDS) { \
266 __bits = (set)->__bits[__i]; \
271 #define SIG_FOREACH(i, set) \
272 for (int32_t __i = -1, __bits = 0; \
273 _SIG_FOREACH_ADVANCE(i, set); ) \
275 sigset_t fastblock_mask;
280 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
281 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
282 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
283 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
284 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
285 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
286 SIGFILLSET(fastblock_mask);
287 SIG_CANTMASK(fastblock_mask);
291 ksiginfo_alloc(int wait)
298 if (ksiginfo_zone != NULL)
299 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
304 ksiginfo_free(ksiginfo_t *ksi)
306 uma_zfree(ksiginfo_zone, ksi);
310 ksiginfo_tryfree(ksiginfo_t *ksi)
312 if (!(ksi->ksi_flags & KSI_EXT)) {
313 uma_zfree(ksiginfo_zone, ksi);
320 sigqueue_init(sigqueue_t *list, struct proc *p)
322 SIGEMPTYSET(list->sq_signals);
323 SIGEMPTYSET(list->sq_kill);
324 SIGEMPTYSET(list->sq_ptrace);
325 TAILQ_INIT(&list->sq_list);
327 list->sq_flags = SQ_INIT;
331 * Get a signal's ksiginfo.
333 * 0 - signal not found
334 * others - signal number
337 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
339 struct proc *p = sq->sq_proc;
340 struct ksiginfo *ksi, *next;
343 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
345 if (!SIGISMEMBER(sq->sq_signals, signo))
348 if (SIGISMEMBER(sq->sq_ptrace, signo)) {
350 SIGDELSET(sq->sq_ptrace, signo);
351 si->ksi_flags |= KSI_PTRACE;
353 if (SIGISMEMBER(sq->sq_kill, signo)) {
356 SIGDELSET(sq->sq_kill, signo);
359 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
360 if (ksi->ksi_signo == signo) {
362 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
363 ksi->ksi_sigq = NULL;
364 ksiginfo_copy(ksi, si);
365 if (ksiginfo_tryfree(ksi) && p != NULL)
374 SIGDELSET(sq->sq_signals, signo);
375 si->ksi_signo = signo;
380 sigqueue_take(ksiginfo_t *ksi)
386 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
390 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
391 ksi->ksi_sigq = NULL;
392 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
395 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
396 kp = TAILQ_NEXT(kp, ksi_link)) {
397 if (kp->ksi_signo == ksi->ksi_signo)
400 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) &&
401 !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo))
402 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
406 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
408 struct proc *p = sq->sq_proc;
409 struct ksiginfo *ksi;
412 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
415 * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path
418 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
419 SIGADDSET(sq->sq_kill, signo);
423 /* directly insert the ksi, don't copy it */
424 if (si->ksi_flags & KSI_INS) {
425 if (si->ksi_flags & KSI_HEAD)
426 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
428 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
433 if (__predict_false(ksiginfo_zone == NULL)) {
434 SIGADDSET(sq->sq_kill, signo);
438 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
441 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
447 ksiginfo_copy(si, ksi);
448 ksi->ksi_signo = signo;
449 if (si->ksi_flags & KSI_HEAD)
450 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
452 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
457 if ((si->ksi_flags & KSI_PTRACE) != 0) {
458 SIGADDSET(sq->sq_ptrace, signo);
461 } else if ((si->ksi_flags & KSI_TRAP) != 0 ||
462 (si->ksi_flags & KSI_SIGQ) == 0) {
463 SIGADDSET(sq->sq_kill, signo);
471 SIGADDSET(sq->sq_signals, signo);
476 sigqueue_flush(sigqueue_t *sq)
478 struct proc *p = sq->sq_proc;
481 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
484 PROC_LOCK_ASSERT(p, MA_OWNED);
486 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
487 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
488 ksi->ksi_sigq = NULL;
489 if (ksiginfo_tryfree(ksi) && p != NULL)
493 SIGEMPTYSET(sq->sq_signals);
494 SIGEMPTYSET(sq->sq_kill);
495 SIGEMPTYSET(sq->sq_ptrace);
499 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
502 struct proc *p1, *p2;
503 ksiginfo_t *ksi, *next;
505 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
506 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
509 /* Move siginfo to target list */
510 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
511 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
512 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
515 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
522 /* Move pending bits to target list */
524 SIGSETAND(tmp, *set);
525 SIGSETOR(dst->sq_kill, tmp);
526 SIGSETNAND(src->sq_kill, tmp);
528 tmp = src->sq_ptrace;
529 SIGSETAND(tmp, *set);
530 SIGSETOR(dst->sq_ptrace, tmp);
531 SIGSETNAND(src->sq_ptrace, tmp);
533 tmp = src->sq_signals;
534 SIGSETAND(tmp, *set);
535 SIGSETOR(dst->sq_signals, tmp);
536 SIGSETNAND(src->sq_signals, tmp);
541 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
546 SIGADDSET(set, signo);
547 sigqueue_move_set(src, dst, &set);
552 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
554 struct proc *p = sq->sq_proc;
555 ksiginfo_t *ksi, *next;
557 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
559 /* Remove siginfo queue */
560 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
561 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
562 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
563 ksi->ksi_sigq = NULL;
564 if (ksiginfo_tryfree(ksi) && p != NULL)
568 SIGSETNAND(sq->sq_kill, *set);
569 SIGSETNAND(sq->sq_ptrace, *set);
570 SIGSETNAND(sq->sq_signals, *set);
574 sigqueue_delete(sigqueue_t *sq, int signo)
579 SIGADDSET(set, signo);
580 sigqueue_delete_set(sq, &set);
583 /* Remove a set of signals for a process */
585 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
590 PROC_LOCK_ASSERT(p, MA_OWNED);
592 sigqueue_init(&worklist, NULL);
593 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
595 FOREACH_THREAD_IN_PROC(p, td0)
596 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
598 sigqueue_flush(&worklist);
602 sigqueue_delete_proc(struct proc *p, int signo)
607 SIGADDSET(set, signo);
608 sigqueue_delete_set_proc(p, &set);
612 sigqueue_delete_stopmask_proc(struct proc *p)
617 SIGADDSET(set, SIGSTOP);
618 SIGADDSET(set, SIGTSTP);
619 SIGADDSET(set, SIGTTIN);
620 SIGADDSET(set, SIGTTOU);
621 sigqueue_delete_set_proc(p, &set);
625 * Determine signal that should be delivered to thread td, the current
626 * thread, 0 if none. If there is a pending stop signal with default
627 * action, the process stops in issignal().
630 cursig(struct thread *td)
632 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
633 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
634 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
635 return (SIGPENDING(td) ? issignal(td) : 0);
639 * Arrange for ast() to handle unmasked pending signals on return to user
640 * mode. This must be called whenever a signal is added to td_sigqueue or
641 * unmasked in td_sigmask.
644 signotify(struct thread *td)
647 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
649 if (SIGPENDING(td)) {
651 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
657 * Returns 1 (true) if altstack is configured for the thread, and the
658 * passed stack bottom address falls into the altstack range. Handles
659 * the 43 compat special case where the alt stack size is zero.
662 sigonstack(size_t sp)
667 if ((td->td_pflags & TDP_ALTSTACK) == 0)
669 #if defined(COMPAT_43)
670 if (SV_PROC_FLAG(td->td_proc, SV_AOUT) && td->td_sigstk.ss_size == 0)
671 return ((td->td_sigstk.ss_flags & SS_ONSTACK) != 0);
673 return (sp >= (size_t)td->td_sigstk.ss_sp &&
674 sp < td->td_sigstk.ss_size + (size_t)td->td_sigstk.ss_sp);
681 if (sig > 0 && sig < nitems(sigproptbl))
682 return (sigproptbl[sig]);
687 sigact_flag_test(const struct sigaction *act, int flag)
691 * SA_SIGINFO is reset when signal disposition is set to
692 * ignore or default. Other flags are kept according to user
695 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
696 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
697 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
707 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
708 struct sigaction *oact, int flags)
711 struct proc *p = td->td_proc;
713 if (!_SIG_VALID(sig))
715 if (act != NULL && act->sa_handler != SIG_DFL &&
716 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
717 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
718 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
723 mtx_lock(&ps->ps_mtx);
725 memset(oact, 0, sizeof(*oact));
726 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
727 if (SIGISMEMBER(ps->ps_sigonstack, sig))
728 oact->sa_flags |= SA_ONSTACK;
729 if (!SIGISMEMBER(ps->ps_sigintr, sig))
730 oact->sa_flags |= SA_RESTART;
731 if (SIGISMEMBER(ps->ps_sigreset, sig))
732 oact->sa_flags |= SA_RESETHAND;
733 if (SIGISMEMBER(ps->ps_signodefer, sig))
734 oact->sa_flags |= SA_NODEFER;
735 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
736 oact->sa_flags |= SA_SIGINFO;
738 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
740 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
741 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
742 oact->sa_flags |= SA_NOCLDSTOP;
743 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
744 oact->sa_flags |= SA_NOCLDWAIT;
747 if ((sig == SIGKILL || sig == SIGSTOP) &&
748 act->sa_handler != SIG_DFL) {
749 mtx_unlock(&ps->ps_mtx);
755 * Change setting atomically.
758 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
759 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
760 if (sigact_flag_test(act, SA_SIGINFO)) {
761 ps->ps_sigact[_SIG_IDX(sig)] =
762 (__sighandler_t *)act->sa_sigaction;
763 SIGADDSET(ps->ps_siginfo, sig);
765 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
766 SIGDELSET(ps->ps_siginfo, sig);
768 if (!sigact_flag_test(act, SA_RESTART))
769 SIGADDSET(ps->ps_sigintr, sig);
771 SIGDELSET(ps->ps_sigintr, sig);
772 if (sigact_flag_test(act, SA_ONSTACK))
773 SIGADDSET(ps->ps_sigonstack, sig);
775 SIGDELSET(ps->ps_sigonstack, sig);
776 if (sigact_flag_test(act, SA_RESETHAND))
777 SIGADDSET(ps->ps_sigreset, sig);
779 SIGDELSET(ps->ps_sigreset, sig);
780 if (sigact_flag_test(act, SA_NODEFER))
781 SIGADDSET(ps->ps_signodefer, sig);
783 SIGDELSET(ps->ps_signodefer, sig);
784 if (sig == SIGCHLD) {
785 if (act->sa_flags & SA_NOCLDSTOP)
786 ps->ps_flag |= PS_NOCLDSTOP;
788 ps->ps_flag &= ~PS_NOCLDSTOP;
789 if (act->sa_flags & SA_NOCLDWAIT) {
791 * Paranoia: since SA_NOCLDWAIT is implemented
792 * by reparenting the dying child to PID 1 (and
793 * trust it to reap the zombie), PID 1 itself
794 * is forbidden to set SA_NOCLDWAIT.
797 ps->ps_flag &= ~PS_NOCLDWAIT;
799 ps->ps_flag |= PS_NOCLDWAIT;
801 ps->ps_flag &= ~PS_NOCLDWAIT;
802 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
803 ps->ps_flag |= PS_CLDSIGIGN;
805 ps->ps_flag &= ~PS_CLDSIGIGN;
808 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
809 * and for signals set to SIG_DFL where the default is to
810 * ignore. However, don't put SIGCONT in ps_sigignore, as we
811 * have to restart the process.
813 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
814 (sigprop(sig) & SIGPROP_IGNORE &&
815 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
816 /* never to be seen again */
817 sigqueue_delete_proc(p, sig);
819 /* easier in psignal */
820 SIGADDSET(ps->ps_sigignore, sig);
821 SIGDELSET(ps->ps_sigcatch, sig);
823 SIGDELSET(ps->ps_sigignore, sig);
824 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
825 SIGDELSET(ps->ps_sigcatch, sig);
827 SIGADDSET(ps->ps_sigcatch, sig);
829 #ifdef COMPAT_FREEBSD4
830 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
831 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
832 (flags & KSA_FREEBSD4) == 0)
833 SIGDELSET(ps->ps_freebsd4, sig);
835 SIGADDSET(ps->ps_freebsd4, sig);
838 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
839 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
840 (flags & KSA_OSIGSET) == 0)
841 SIGDELSET(ps->ps_osigset, sig);
843 SIGADDSET(ps->ps_osigset, sig);
846 mtx_unlock(&ps->ps_mtx);
851 #ifndef _SYS_SYSPROTO_H_
852 struct sigaction_args {
854 struct sigaction *act;
855 struct sigaction *oact;
859 sys_sigaction(struct thread *td, struct sigaction_args *uap)
861 struct sigaction act, oact;
862 struct sigaction *actp, *oactp;
865 actp = (uap->act != NULL) ? &act : NULL;
866 oactp = (uap->oact != NULL) ? &oact : NULL;
868 error = copyin(uap->act, actp, sizeof(act));
872 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
874 error = copyout(oactp, uap->oact, sizeof(oact));
878 #ifdef COMPAT_FREEBSD4
879 #ifndef _SYS_SYSPROTO_H_
880 struct freebsd4_sigaction_args {
882 struct sigaction *act;
883 struct sigaction *oact;
887 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
889 struct sigaction act, oact;
890 struct sigaction *actp, *oactp;
893 actp = (uap->act != NULL) ? &act : NULL;
894 oactp = (uap->oact != NULL) ? &oact : NULL;
896 error = copyin(uap->act, actp, sizeof(act));
900 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
902 error = copyout(oactp, uap->oact, sizeof(oact));
905 #endif /* COMAPT_FREEBSD4 */
907 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
908 #ifndef _SYS_SYSPROTO_H_
909 struct osigaction_args {
911 struct osigaction *nsa;
912 struct osigaction *osa;
916 osigaction(struct thread *td, struct osigaction_args *uap)
918 struct osigaction sa;
919 struct sigaction nsa, osa;
920 struct sigaction *nsap, *osap;
923 if (uap->signum <= 0 || uap->signum >= ONSIG)
926 nsap = (uap->nsa != NULL) ? &nsa : NULL;
927 osap = (uap->osa != NULL) ? &osa : NULL;
930 error = copyin(uap->nsa, &sa, sizeof(sa));
933 nsap->sa_handler = sa.sa_handler;
934 nsap->sa_flags = sa.sa_flags;
935 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
937 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
938 if (osap && !error) {
939 sa.sa_handler = osap->sa_handler;
940 sa.sa_flags = osap->sa_flags;
941 SIG2OSIG(osap->sa_mask, sa.sa_mask);
942 error = copyout(&sa, uap->osa, sizeof(sa));
947 #if !defined(__i386__)
948 /* Avoid replicating the same stub everywhere */
950 osigreturn(struct thread *td, struct osigreturn_args *uap)
953 return (nosys(td, (struct nosys_args *)uap));
956 #endif /* COMPAT_43 */
959 * Initialize signal state for process 0;
960 * set to ignore signals that are ignored by default.
963 siginit(struct proc *p)
970 mtx_lock(&ps->ps_mtx);
971 for (i = 1; i <= NSIG; i++) {
972 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
973 SIGADDSET(ps->ps_sigignore, i);
976 mtx_unlock(&ps->ps_mtx);
981 * Reset specified signal to the default disposition.
984 sigdflt(struct sigacts *ps, int sig)
987 mtx_assert(&ps->ps_mtx, MA_OWNED);
988 SIGDELSET(ps->ps_sigcatch, sig);
989 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
990 SIGADDSET(ps->ps_sigignore, sig);
991 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
992 SIGDELSET(ps->ps_siginfo, sig);
996 * Reset signals for an exec of the specified process.
999 execsigs(struct proc *p)
1001 sigset_t osigignore;
1007 * Reset caught signals. Held signals remain held
1008 * through td_sigmask (unless they were caught,
1009 * and are now ignored by default).
1011 PROC_LOCK_ASSERT(p, MA_OWNED);
1013 mtx_lock(&ps->ps_mtx);
1017 * As CloudABI processes cannot modify signal handlers, fully
1018 * reset all signals to their default behavior. Do ignore
1019 * SIGPIPE, as it would otherwise be impossible to recover from
1020 * writes to broken pipes and sockets.
1022 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
1023 osigignore = ps->ps_sigignore;
1024 SIG_FOREACH(sig, &osigignore) {
1028 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1032 * Reset stack state to the user stack.
1033 * Clear set of signals caught on the signal stack.
1036 MPASS(td->td_proc == p);
1037 td->td_sigstk.ss_flags = SS_DISABLE;
1038 td->td_sigstk.ss_size = 0;
1039 td->td_sigstk.ss_sp = 0;
1040 td->td_pflags &= ~TDP_ALTSTACK;
1042 * Reset no zombies if child dies flag as Solaris does.
1044 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1045 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1046 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1047 mtx_unlock(&ps->ps_mtx);
1051 * kern_sigprocmask()
1053 * Manipulate signal mask.
1056 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1059 sigset_t new_block, oset1;
1064 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1065 PROC_LOCK_ASSERT(p, MA_OWNED);
1068 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1069 ? MA_OWNED : MA_NOTOWNED);
1071 *oset = td->td_sigmask;
1078 oset1 = td->td_sigmask;
1079 SIGSETOR(td->td_sigmask, *set);
1080 new_block = td->td_sigmask;
1081 SIGSETNAND(new_block, oset1);
1084 SIGSETNAND(td->td_sigmask, *set);
1089 oset1 = td->td_sigmask;
1090 if (flags & SIGPROCMASK_OLD)
1091 SIGSETLO(td->td_sigmask, *set);
1093 td->td_sigmask = *set;
1094 new_block = td->td_sigmask;
1095 SIGSETNAND(new_block, oset1);
1104 * The new_block set contains signals that were not previously
1105 * blocked, but are blocked now.
1107 * In case we block any signal that was not previously blocked
1108 * for td, and process has the signal pending, try to schedule
1109 * signal delivery to some thread that does not block the
1110 * signal, possibly waking it up.
1112 if (p->p_numthreads != 1)
1113 reschedule_signals(p, new_block, flags);
1117 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1122 #ifndef _SYS_SYSPROTO_H_
1123 struct sigprocmask_args {
1125 const sigset_t *set;
1130 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1133 sigset_t *setp, *osetp;
1136 setp = (uap->set != NULL) ? &set : NULL;
1137 osetp = (uap->oset != NULL) ? &oset : NULL;
1139 error = copyin(uap->set, setp, sizeof(set));
1143 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1144 if (osetp && !error) {
1145 error = copyout(osetp, uap->oset, sizeof(oset));
1150 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1151 #ifndef _SYS_SYSPROTO_H_
1152 struct osigprocmask_args {
1158 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1163 OSIG2SIG(uap->mask, set);
1164 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1165 SIG2OSIG(oset, td->td_retval[0]);
1168 #endif /* COMPAT_43 */
1171 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1177 error = copyin(uap->set, &set, sizeof(set));
1179 td->td_retval[0] = error;
1183 error = kern_sigtimedwait(td, set, &ksi, NULL);
1186 * sigwait() function shall not return EINTR, but
1187 * the syscall does. Non-ancient libc provides the
1188 * wrapper which hides EINTR. Otherwise, EINTR return
1189 * is used by libthr to handle required cancellation
1190 * point in the sigwait().
1192 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1194 td->td_retval[0] = error;
1198 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1199 td->td_retval[0] = error;
1204 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1207 struct timespec *timeout;
1213 error = copyin(uap->timeout, &ts, sizeof(ts));
1221 error = copyin(uap->set, &set, sizeof(set));
1225 error = kern_sigtimedwait(td, set, &ksi, timeout);
1230 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1233 td->td_retval[0] = ksi.ksi_signo;
1238 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1244 error = copyin(uap->set, &set, sizeof(set));
1248 error = kern_sigtimedwait(td, set, &ksi, NULL);
1253 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1256 td->td_retval[0] = ksi.ksi_signo;
1261 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1265 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1269 thr->td_si.si_signo = 0;
1274 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1275 struct timespec *timeout)
1278 sigset_t saved_mask, new_block;
1280 int error, sig, timo, timevalid = 0;
1281 struct timespec rts, ets, ts;
1291 /* Ensure the sigfastblock value is up to date. */
1292 sigfastblock_fetch(td);
1294 if (timeout != NULL) {
1295 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1297 getnanouptime(&rts);
1298 timespecadd(&rts, timeout, &ets);
1302 /* Some signals can not be waited for. */
1303 SIG_CANTMASK(waitset);
1306 saved_mask = td->td_sigmask;
1307 SIGSETNAND(td->td_sigmask, waitset);
1308 if ((p->p_sysent->sv_flags & SV_SIG_DISCIGN) != 0 ||
1309 !kern_sig_discard_ign) {
1311 td->td_flags |= TDF_SIGWAIT;
1315 mtx_lock(&ps->ps_mtx);
1317 mtx_unlock(&ps->ps_mtx);
1318 KASSERT(sig >= 0, ("sig %d", sig));
1319 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1320 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1321 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1331 * POSIX says this must be checked after looking for pending
1334 if (timeout != NULL) {
1339 getnanouptime(&rts);
1340 if (timespeccmp(&rts, &ets, >=)) {
1344 timespecsub(&ets, &rts, &ts);
1345 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1356 error = msleep(&p->p_sigacts, &p->p_mtx, PPAUSE | PCATCH,
1359 /* The syscalls can not be restarted. */
1360 if (error == ERESTART)
1363 /* We will calculate timeout by ourself. */
1364 if (timeout != NULL && error == EAGAIN)
1368 * If PTRACE_SCE or PTRACE_SCX were set after
1369 * userspace entered the syscall, return spurious
1370 * EINTR after wait was done. Only do this as last
1371 * resort after rechecking for possible queued signals
1372 * and expired timeouts.
1374 if (error == 0 && (p->p_ptevents & PTRACE_SYSCALL) != 0)
1378 td->td_flags &= ~TDF_SIGWAIT;
1381 new_block = saved_mask;
1382 SIGSETNAND(new_block, td->td_sigmask);
1383 td->td_sigmask = saved_mask;
1385 * Fewer signals can be delivered to us, reschedule signal
1388 if (p->p_numthreads != 1)
1389 reschedule_signals(p, new_block, 0);
1392 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1394 if (ksi->ksi_code == SI_TIMER)
1395 itimer_accept(p, ksi->ksi_timerid, ksi);
1398 if (KTRPOINT(td, KTR_PSIG)) {
1401 mtx_lock(&ps->ps_mtx);
1402 action = ps->ps_sigact[_SIG_IDX(sig)];
1403 mtx_unlock(&ps->ps_mtx);
1404 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1407 if (sig == SIGKILL) {
1408 proc_td_siginfo_capture(td, &ksi->ksi_info);
1416 #ifndef _SYS_SYSPROTO_H_
1417 struct sigpending_args {
1422 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1424 struct proc *p = td->td_proc;
1428 pending = p->p_sigqueue.sq_signals;
1429 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1431 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1434 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1435 #ifndef _SYS_SYSPROTO_H_
1436 struct osigpending_args {
1441 osigpending(struct thread *td, struct osigpending_args *uap)
1443 struct proc *p = td->td_proc;
1447 pending = p->p_sigqueue.sq_signals;
1448 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1450 SIG2OSIG(pending, td->td_retval[0]);
1453 #endif /* COMPAT_43 */
1455 #if defined(COMPAT_43)
1457 * Generalized interface signal handler, 4.3-compatible.
1459 #ifndef _SYS_SYSPROTO_H_
1460 struct osigvec_args {
1468 osigvec(struct thread *td, struct osigvec_args *uap)
1471 struct sigaction nsa, osa;
1472 struct sigaction *nsap, *osap;
1475 if (uap->signum <= 0 || uap->signum >= ONSIG)
1477 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1478 osap = (uap->osv != NULL) ? &osa : NULL;
1480 error = copyin(uap->nsv, &vec, sizeof(vec));
1483 nsap->sa_handler = vec.sv_handler;
1484 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1485 nsap->sa_flags = vec.sv_flags;
1486 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1488 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1489 if (osap && !error) {
1490 vec.sv_handler = osap->sa_handler;
1491 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1492 vec.sv_flags = osap->sa_flags;
1493 vec.sv_flags &= ~SA_NOCLDWAIT;
1494 vec.sv_flags ^= SA_RESTART;
1495 error = copyout(&vec, uap->osv, sizeof(vec));
1500 #ifndef _SYS_SYSPROTO_H_
1501 struct osigblock_args {
1506 osigblock(struct thread *td, struct osigblock_args *uap)
1510 OSIG2SIG(uap->mask, set);
1511 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1512 SIG2OSIG(oset, td->td_retval[0]);
1516 #ifndef _SYS_SYSPROTO_H_
1517 struct osigsetmask_args {
1522 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1526 OSIG2SIG(uap->mask, set);
1527 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1528 SIG2OSIG(oset, td->td_retval[0]);
1531 #endif /* COMPAT_43 */
1534 * Suspend calling thread until signal, providing mask to be set in the
1537 #ifndef _SYS_SYSPROTO_H_
1538 struct sigsuspend_args {
1539 const sigset_t *sigmask;
1544 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1549 error = copyin(uap->sigmask, &mask, sizeof(mask));
1552 return (kern_sigsuspend(td, mask));
1556 kern_sigsuspend(struct thread *td, sigset_t mask)
1558 struct proc *p = td->td_proc;
1561 /* Ensure the sigfastblock value is up to date. */
1562 sigfastblock_fetch(td);
1565 * When returning from sigsuspend, we want
1566 * the old mask to be restored after the
1567 * signal handler has finished. Thus, we
1568 * save it here and mark the sigacts structure
1572 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1573 SIGPROCMASK_PROC_LOCKED);
1574 td->td_pflags |= TDP_OLDMASK;
1577 * Process signals now. Otherwise, we can get spurious wakeup
1578 * due to signal entered process queue, but delivered to other
1579 * thread. But sigsuspend should return only on signal
1582 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1583 for (has_sig = 0; !has_sig;) {
1584 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1587 thread_suspend_check(0);
1588 mtx_lock(&p->p_sigacts->ps_mtx);
1589 while ((sig = cursig(td)) != 0) {
1590 KASSERT(sig >= 0, ("sig %d", sig));
1591 has_sig += postsig(sig);
1593 mtx_unlock(&p->p_sigacts->ps_mtx);
1596 * If PTRACE_SCE or PTRACE_SCX were set after
1597 * userspace entered the syscall, return spurious
1600 if ((p->p_ptevents & PTRACE_SYSCALL) != 0)
1604 td->td_errno = EINTR;
1605 td->td_pflags |= TDP_NERRNO;
1606 return (EJUSTRETURN);
1609 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1611 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1612 * convention: libc stub passes mask, not pointer, to save a copyin.
1614 #ifndef _SYS_SYSPROTO_H_
1615 struct osigsuspend_args {
1621 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1625 OSIG2SIG(uap->mask, mask);
1626 return (kern_sigsuspend(td, mask));
1628 #endif /* COMPAT_43 */
1630 #if defined(COMPAT_43)
1631 #ifndef _SYS_SYSPROTO_H_
1632 struct osigstack_args {
1633 struct sigstack *nss;
1634 struct sigstack *oss;
1639 osigstack(struct thread *td, struct osigstack_args *uap)
1641 struct sigstack nss, oss;
1644 if (uap->nss != NULL) {
1645 error = copyin(uap->nss, &nss, sizeof(nss));
1649 oss.ss_sp = td->td_sigstk.ss_sp;
1650 oss.ss_onstack = sigonstack(cpu_getstack(td));
1651 if (uap->nss != NULL) {
1652 td->td_sigstk.ss_sp = nss.ss_sp;
1653 td->td_sigstk.ss_size = 0;
1654 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1655 td->td_pflags |= TDP_ALTSTACK;
1657 if (uap->oss != NULL)
1658 error = copyout(&oss, uap->oss, sizeof(oss));
1662 #endif /* COMPAT_43 */
1664 #ifndef _SYS_SYSPROTO_H_
1665 struct sigaltstack_args {
1672 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1677 if (uap->ss != NULL) {
1678 error = copyin(uap->ss, &ss, sizeof(ss));
1682 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1683 (uap->oss != NULL) ? &oss : NULL);
1686 if (uap->oss != NULL)
1687 error = copyout(&oss, uap->oss, sizeof(stack_t));
1692 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1694 struct proc *p = td->td_proc;
1697 oonstack = sigonstack(cpu_getstack(td));
1700 *oss = td->td_sigstk;
1701 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1702 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1708 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1710 if (!(ss->ss_flags & SS_DISABLE)) {
1711 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1714 td->td_sigstk = *ss;
1715 td->td_pflags |= TDP_ALTSTACK;
1717 td->td_pflags &= ~TDP_ALTSTACK;
1723 struct killpg1_ctx {
1733 killpg1_sendsig(struct proc *p, bool notself, struct killpg1_ctx *arg)
1737 if (p->p_pid <= 1 || (p->p_flag & P_SYSTEM) != 0 ||
1738 (notself && p == arg->td->td_proc) || p->p_state == PRS_NEW)
1741 err = p_cansignal(arg->td, p, arg->sig);
1742 if (err == 0 && arg->sig != 0)
1743 pksignal(p, arg->sig, arg->ksi);
1749 else if (arg->ret == 0 && err != ESRCH && err != EPERM)
1754 * Common code for kill process group/broadcast kill.
1755 * cp is calling process.
1758 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1762 struct killpg1_ctx arg;
1774 sx_slock(&allproc_lock);
1775 FOREACH_PROC_IN_SYSTEM(p) {
1776 killpg1_sendsig(p, true, &arg);
1778 sx_sunlock(&allproc_lock);
1780 sx_slock(&proctree_lock);
1783 * zero pgid means send to my process group.
1785 pgrp = td->td_proc->p_pgrp;
1788 pgrp = pgfind(pgid);
1790 sx_sunlock(&proctree_lock);
1794 sx_sunlock(&proctree_lock);
1795 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1796 killpg1_sendsig(p, false, &arg);
1800 MPASS(arg.ret != 0 || arg.found || !arg.sent);
1801 if (arg.ret == 0 && !arg.sent)
1802 arg.ret = arg.found ? EPERM : ESRCH;
1806 #ifndef _SYS_SYSPROTO_H_
1814 sys_kill(struct thread *td, struct kill_args *uap)
1817 return (kern_kill(td, uap->pid, uap->signum));
1821 kern_kill(struct thread *td, pid_t pid, int signum)
1828 * A process in capability mode can send signals only to himself.
1829 * The main rationale behind this is that abort(3) is implemented as
1830 * kill(getpid(), SIGABRT).
1832 if (IN_CAPABILITY_MODE(td) && pid != td->td_proc->p_pid)
1835 AUDIT_ARG_SIGNUM(signum);
1837 if ((u_int)signum > _SIG_MAXSIG)
1840 ksiginfo_init(&ksi);
1841 ksi.ksi_signo = signum;
1842 ksi.ksi_code = SI_USER;
1843 ksi.ksi_pid = td->td_proc->p_pid;
1844 ksi.ksi_uid = td->td_ucred->cr_ruid;
1847 /* kill single process */
1848 if ((p = pfind_any(pid)) == NULL)
1850 AUDIT_ARG_PROCESS(p);
1851 error = p_cansignal(td, p, signum);
1852 if (error == 0 && signum)
1853 pksignal(p, signum, &ksi);
1858 case -1: /* broadcast signal */
1859 return (killpg1(td, signum, 0, 1, &ksi));
1860 case 0: /* signal own process group */
1861 return (killpg1(td, signum, 0, 0, &ksi));
1862 default: /* negative explicit process group */
1863 return (killpg1(td, signum, -pid, 0, &ksi));
1869 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1874 AUDIT_ARG_SIGNUM(uap->signum);
1875 AUDIT_ARG_FD(uap->fd);
1876 if ((u_int)uap->signum > _SIG_MAXSIG)
1879 error = procdesc_find(td, uap->fd, &cap_pdkill_rights, &p);
1882 AUDIT_ARG_PROCESS(p);
1883 error = p_cansignal(td, p, uap->signum);
1884 if (error == 0 && uap->signum)
1885 kern_psignal(p, uap->signum);
1890 #if defined(COMPAT_43)
1891 #ifndef _SYS_SYSPROTO_H_
1892 struct okillpg_args {
1899 okillpg(struct thread *td, struct okillpg_args *uap)
1903 AUDIT_ARG_SIGNUM(uap->signum);
1904 AUDIT_ARG_PID(uap->pgid);
1905 if ((u_int)uap->signum > _SIG_MAXSIG)
1908 ksiginfo_init(&ksi);
1909 ksi.ksi_signo = uap->signum;
1910 ksi.ksi_code = SI_USER;
1911 ksi.ksi_pid = td->td_proc->p_pid;
1912 ksi.ksi_uid = td->td_ucred->cr_ruid;
1913 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1915 #endif /* COMPAT_43 */
1917 #ifndef _SYS_SYSPROTO_H_
1918 struct sigqueue_args {
1921 /* union sigval */ void *value;
1925 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1929 sv.sival_ptr = uap->value;
1931 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1935 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1941 if ((u_int)signum > _SIG_MAXSIG)
1945 * Specification says sigqueue can only send signal to
1951 if ((p = pfind_any(pid)) == NULL)
1953 error = p_cansignal(td, p, signum);
1954 if (error == 0 && signum != 0) {
1955 ksiginfo_init(&ksi);
1956 ksi.ksi_flags = KSI_SIGQ;
1957 ksi.ksi_signo = signum;
1958 ksi.ksi_code = SI_QUEUE;
1959 ksi.ksi_pid = td->td_proc->p_pid;
1960 ksi.ksi_uid = td->td_ucred->cr_ruid;
1961 ksi.ksi_value = *value;
1962 error = pksignal(p, ksi.ksi_signo, &ksi);
1969 * Send a signal to a process group.
1972 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1977 sx_slock(&proctree_lock);
1978 pgrp = pgfind(pgid);
1979 sx_sunlock(&proctree_lock);
1981 pgsignal(pgrp, sig, 0, ksi);
1988 * Send a signal to a process group. If checktty is 1,
1989 * limit to members which have a controlling terminal.
1992 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1997 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1998 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
2000 if (p->p_state == PRS_NORMAL &&
2001 (checkctty == 0 || p->p_flag & P_CONTROLT))
2002 pksignal(p, sig, ksi);
2009 * Recalculate the signal mask and reset the signal disposition after
2010 * usermode frame for delivery is formed. Should be called after
2011 * mach-specific routine, because sysent->sv_sendsig() needs correct
2012 * ps_siginfo and signal mask.
2015 postsig_done(int sig, struct thread *td, struct sigacts *ps)
2019 mtx_assert(&ps->ps_mtx, MA_OWNED);
2020 td->td_ru.ru_nsignals++;
2021 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2022 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2023 SIGADDSET(mask, sig);
2024 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2025 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2026 if (SIGISMEMBER(ps->ps_sigreset, sig))
2031 * Send a signal caused by a trap to the current thread. If it will be
2032 * caught immediately, deliver it with correct code. Otherwise, post it
2036 trapsignal(struct thread *td, ksiginfo_t *ksi)
2044 sig = ksi->ksi_signo;
2045 code = ksi->ksi_code;
2046 KASSERT(_SIG_VALID(sig), ("invalid signal"));
2048 sigfastblock_fetch(td);
2051 mtx_lock(&ps->ps_mtx);
2052 sigmask = td->td_sigmask;
2053 if (td->td_sigblock_val != 0)
2054 SIGSETOR(sigmask, fastblock_mask);
2055 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
2056 !SIGISMEMBER(sigmask, sig)) {
2058 if (KTRPOINT(curthread, KTR_PSIG))
2059 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
2060 &td->td_sigmask, code);
2062 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
2063 ksi, &td->td_sigmask);
2064 postsig_done(sig, td, ps);
2065 mtx_unlock(&ps->ps_mtx);
2068 * Avoid a possible infinite loop if the thread
2069 * masking the signal or process is ignoring the
2072 if (kern_forcesigexit && (SIGISMEMBER(sigmask, sig) ||
2073 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
2074 SIGDELSET(td->td_sigmask, sig);
2075 SIGDELSET(ps->ps_sigcatch, sig);
2076 SIGDELSET(ps->ps_sigignore, sig);
2077 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2078 td->td_pflags &= ~TDP_SIGFASTBLOCK;
2079 td->td_sigblock_val = 0;
2081 mtx_unlock(&ps->ps_mtx);
2082 p->p_sig = sig; /* XXX to verify code */
2083 tdsendsignal(p, td, sig, ksi);
2088 static struct thread *
2089 sigtd(struct proc *p, int sig, bool fast_sigblock)
2091 struct thread *td, *signal_td;
2093 PROC_LOCK_ASSERT(p, MA_OWNED);
2094 MPASS(!fast_sigblock || p == curproc);
2097 * Check if current thread can handle the signal without
2098 * switching context to another thread.
2100 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig) &&
2101 (!fast_sigblock || curthread->td_sigblock_val == 0))
2104 FOREACH_THREAD_IN_PROC(p, td) {
2105 if (!SIGISMEMBER(td->td_sigmask, sig) && (!fast_sigblock ||
2106 td != curthread || td->td_sigblock_val == 0)) {
2111 if (signal_td == NULL)
2112 signal_td = FIRST_THREAD_IN_PROC(p);
2117 * Send the signal to the process. If the signal has an action, the action
2118 * is usually performed by the target process rather than the caller; we add
2119 * the signal to the set of pending signals for the process.
2122 * o When a stop signal is sent to a sleeping process that takes the
2123 * default action, the process is stopped without awakening it.
2124 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2125 * regardless of the signal action (eg, blocked or ignored).
2127 * Other ignored signals are discarded immediately.
2129 * NB: This function may be entered from the debugger via the "kill" DDB
2130 * command. There is little that can be done to mitigate the possibly messy
2131 * side effects of this unwise possibility.
2134 kern_psignal(struct proc *p, int sig)
2138 ksiginfo_init(&ksi);
2139 ksi.ksi_signo = sig;
2140 ksi.ksi_code = SI_KERNEL;
2141 (void) tdsendsignal(p, NULL, sig, &ksi);
2145 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2148 return (tdsendsignal(p, NULL, sig, ksi));
2151 /* Utility function for finding a thread to send signal event to. */
2153 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2157 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2158 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2170 tdsignal(struct thread *td, int sig)
2174 ksiginfo_init(&ksi);
2175 ksi.ksi_signo = sig;
2176 ksi.ksi_code = SI_KERNEL;
2177 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2181 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2184 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2188 sig_sleepq_abort(struct thread *td, int intrval)
2190 THREAD_LOCK_ASSERT(td, MA_OWNED);
2192 if (intrval == 0 && (td->td_flags & TDF_SIGWAIT) == 0) {
2196 return (sleepq_abort(td, intrval));
2200 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2203 sigqueue_t *sigqueue;
2210 MPASS(td == NULL || p == td->td_proc);
2211 PROC_LOCK_ASSERT(p, MA_OWNED);
2213 if (!_SIG_VALID(sig))
2214 panic("%s(): invalid signal %d", __func__, sig);
2216 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2219 * IEEE Std 1003.1-2001: return success when killing a zombie.
2221 if (p->p_state == PRS_ZOMBIE) {
2222 if (ksi && (ksi->ksi_flags & KSI_INS))
2223 ksiginfo_tryfree(ksi);
2228 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2229 prop = sigprop(sig);
2232 td = sigtd(p, sig, false);
2233 sigqueue = &p->p_sigqueue;
2235 sigqueue = &td->td_sigqueue;
2237 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2240 * If the signal is being ignored, then we forget about it
2241 * immediately, except when the target process executes
2242 * sigwait(). (Note: we don't set SIGCONT in ps_sigignore,
2243 * and if it is set to SIG_IGN, action will be SIG_DFL here.)
2245 mtx_lock(&ps->ps_mtx);
2246 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2247 if (kern_sig_discard_ign &&
2248 (p->p_sysent->sv_flags & SV_SIG_DISCIGN) == 0) {
2249 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2251 mtx_unlock(&ps->ps_mtx);
2252 if (ksi && (ksi->ksi_flags & KSI_INS))
2253 ksiginfo_tryfree(ksi);
2260 if (SIGISMEMBER(td->td_sigmask, sig))
2262 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2266 if (SIGISMEMBER(ps->ps_sigintr, sig))
2271 mtx_unlock(&ps->ps_mtx);
2273 if (prop & SIGPROP_CONT)
2274 sigqueue_delete_stopmask_proc(p);
2275 else if (prop & SIGPROP_STOP) {
2277 * If sending a tty stop signal to a member of an orphaned
2278 * process group, discard the signal here if the action
2279 * is default; don't stop the process below if sleeping,
2280 * and don't clear any pending SIGCONT.
2282 if ((prop & SIGPROP_TTYSTOP) != 0 &&
2283 (p->p_pgrp->pg_flags & PGRP_ORPHANED) != 0 &&
2284 action == SIG_DFL) {
2285 if (ksi && (ksi->ksi_flags & KSI_INS))
2286 ksiginfo_tryfree(ksi);
2289 sigqueue_delete_proc(p, SIGCONT);
2290 if (p->p_flag & P_CONTINUED) {
2291 p->p_flag &= ~P_CONTINUED;
2292 PROC_LOCK(p->p_pptr);
2293 sigqueue_take(p->p_ksi);
2294 PROC_UNLOCK(p->p_pptr);
2298 ret = sigqueue_add(sigqueue, sig, ksi);
2303 * Defer further processing for signals which are held,
2304 * except that stopped processes must be continued by SIGCONT.
2306 if (action == SIG_HOLD &&
2307 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2313 * Some signals have a process-wide effect and a per-thread
2314 * component. Most processing occurs when the process next
2315 * tries to cross the user boundary, however there are some
2316 * times when processing needs to be done immediately, such as
2317 * waking up threads so that they can cross the user boundary.
2318 * We try to do the per-process part here.
2320 if (P_SHOULDSTOP(p)) {
2321 KASSERT(!(p->p_flag & P_WEXIT),
2322 ("signal to stopped but exiting process"));
2323 if (sig == SIGKILL) {
2325 * If traced process is already stopped,
2326 * then no further action is necessary.
2328 if (p->p_flag & P_TRACED)
2331 * SIGKILL sets process running.
2332 * It will die elsewhere.
2333 * All threads must be restarted.
2335 p->p_flag &= ~P_STOPPED_SIG;
2339 if (prop & SIGPROP_CONT) {
2341 * If traced process is already stopped,
2342 * then no further action is necessary.
2344 if (p->p_flag & P_TRACED)
2347 * If SIGCONT is default (or ignored), we continue the
2348 * process but don't leave the signal in sigqueue as
2349 * it has no further action. If SIGCONT is held, we
2350 * continue the process and leave the signal in
2351 * sigqueue. If the process catches SIGCONT, let it
2352 * handle the signal itself. If it isn't waiting on
2353 * an event, it goes back to run state.
2354 * Otherwise, process goes back to sleep state.
2356 p->p_flag &= ~P_STOPPED_SIG;
2358 if (p->p_numthreads == p->p_suspcount) {
2360 p->p_flag |= P_CONTINUED;
2361 p->p_xsig = SIGCONT;
2362 PROC_LOCK(p->p_pptr);
2363 childproc_continued(p);
2364 PROC_UNLOCK(p->p_pptr);
2367 if (action == SIG_DFL) {
2368 thread_unsuspend(p);
2370 sigqueue_delete(sigqueue, sig);
2373 if (action == SIG_CATCH) {
2375 * The process wants to catch it so it needs
2376 * to run at least one thread, but which one?
2382 * The signal is not ignored or caught.
2384 thread_unsuspend(p);
2389 if (prop & SIGPROP_STOP) {
2391 * If traced process is already stopped,
2392 * then no further action is necessary.
2394 if (p->p_flag & P_TRACED)
2397 * Already stopped, don't need to stop again
2398 * (If we did the shell could get confused).
2399 * Just make sure the signal STOP bit set.
2401 p->p_flag |= P_STOPPED_SIG;
2402 sigqueue_delete(sigqueue, sig);
2407 * All other kinds of signals:
2408 * If a thread is sleeping interruptibly, simulate a
2409 * wakeup so that when it is continued it will be made
2410 * runnable and can look at the signal. However, don't make
2411 * the PROCESS runnable, leave it stopped.
2412 * It may run a bit until it hits a thread_suspend_check().
2416 if (TD_CAN_ABORT(td))
2417 wakeup_swapper = sig_sleepq_abort(td, intrval);
2423 * Mutexes are short lived. Threads waiting on them will
2424 * hit thread_suspend_check() soon.
2426 } else if (p->p_state == PRS_NORMAL) {
2427 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2428 tdsigwakeup(td, sig, action, intrval);
2432 MPASS(action == SIG_DFL);
2434 if (prop & SIGPROP_STOP) {
2435 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2437 p->p_flag |= P_STOPPED_SIG;
2440 wakeup_swapper = sig_suspend_threads(td, p, 1);
2441 if (p->p_numthreads == p->p_suspcount) {
2443 * only thread sending signal to another
2444 * process can reach here, if thread is sending
2445 * signal to its process, because thread does
2446 * not suspend itself here, p_numthreads
2447 * should never be equal to p_suspcount.
2451 sigqueue_delete_proc(p, p->p_xsig);
2457 /* Not in "NORMAL" state. discard the signal. */
2458 sigqueue_delete(sigqueue, sig);
2463 * The process is not stopped so we need to apply the signal to all the
2467 tdsigwakeup(td, sig, action, intrval);
2469 thread_unsuspend(p);
2472 itimer_proc_continue(p);
2473 kqtimer_proc_continue(p);
2475 /* If we jump here, proc slock should not be owned. */
2476 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2484 * The force of a signal has been directed against a single
2485 * thread. We need to see what we can do about knocking it
2486 * out of any sleep it may be in etc.
2489 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2491 struct proc *p = td->td_proc;
2492 int prop, wakeup_swapper;
2494 PROC_LOCK_ASSERT(p, MA_OWNED);
2495 prop = sigprop(sig);
2500 * Bring the priority of a thread up if we want it to get
2501 * killed in this lifetime. Be careful to avoid bumping the
2502 * priority of the idle thread, since we still allow to signal
2505 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2506 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2507 sched_prio(td, PUSER);
2508 if (TD_ON_SLEEPQ(td)) {
2510 * If thread is sleeping uninterruptibly
2511 * we can't interrupt the sleep... the signal will
2512 * be noticed when the process returns through
2513 * trap() or syscall().
2515 if ((td->td_flags & TDF_SINTR) == 0)
2518 * If SIGCONT is default (or ignored) and process is
2519 * asleep, we are finished; the process should not
2522 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2525 sigqueue_delete(&p->p_sigqueue, sig);
2527 * It may be on either list in this state.
2528 * Remove from both for now.
2530 sigqueue_delete(&td->td_sigqueue, sig);
2535 * Don't awaken a sleeping thread for SIGSTOP if the
2536 * STOP signal is deferred.
2538 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2539 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2543 * Give low priority threads a better chance to run.
2545 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2546 sched_prio(td, PUSER);
2548 wakeup_swapper = sig_sleepq_abort(td, intrval);
2556 * Other states do nothing with the signal immediately,
2557 * other than kicking ourselves if we are running.
2558 * It will either never be noticed, or noticed very soon.
2561 if (TD_IS_RUNNING(td) && td != curthread)
2571 ptrace_coredump(struct thread *td)
2574 struct thr_coredump_req *tcq;
2577 MPASS(td == curthread);
2579 PROC_LOCK_ASSERT(p, MA_OWNED);
2580 if ((td->td_dbgflags & TDB_COREDUMPRQ) == 0)
2582 KASSERT((p->p_flag & P_STOPPED_TRACE) != 0, ("not stopped"));
2584 tcq = td->td_coredump;
2585 KASSERT(tcq != NULL, ("td_coredump is NULL"));
2587 if (p->p_sysent->sv_coredump == NULL) {
2588 tcq->tc_error = ENOSYS;
2593 rl_cookie = vn_rangelock_wlock(tcq->tc_vp, 0, OFF_MAX);
2595 tcq->tc_error = p->p_sysent->sv_coredump(td, tcq->tc_vp,
2596 tcq->tc_limit, tcq->tc_flags);
2598 vn_rangelock_unlock(tcq->tc_vp, rl_cookie);
2601 td->td_dbgflags &= ~TDB_COREDUMPRQ;
2602 td->td_coredump = NULL;
2607 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2612 PROC_LOCK_ASSERT(p, MA_OWNED);
2613 PROC_SLOCK_ASSERT(p, MA_OWNED);
2614 MPASS(sending || td == curthread);
2617 FOREACH_THREAD_IN_PROC(p, td2) {
2619 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2620 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2621 (td2->td_flags & TDF_SINTR)) {
2622 if (td2->td_flags & TDF_SBDRY) {
2624 * Once a thread is asleep with
2625 * TDF_SBDRY and without TDF_SERESTART
2626 * or TDF_SEINTR set, it should never
2627 * become suspended due to this check.
2629 KASSERT(!TD_IS_SUSPENDED(td2),
2630 ("thread with deferred stops suspended"));
2631 if (TD_SBDRY_INTR(td2)) {
2632 wakeup_swapper |= sleepq_abort(td2,
2633 TD_SBDRY_ERRNO(td2));
2636 } else if (!TD_IS_SUSPENDED(td2))
2637 thread_suspend_one(td2);
2638 } else if (!TD_IS_SUSPENDED(td2)) {
2639 if (sending || td != td2)
2640 td2->td_flags |= TDF_ASTPENDING;
2642 if (TD_IS_RUNNING(td2) && td2 != td)
2643 forward_signal(td2);
2648 return (wakeup_swapper);
2652 * Stop the process for an event deemed interesting to the debugger. If si is
2653 * non-NULL, this is a signal exchange; the new signal requested by the
2654 * debugger will be returned for handling. If si is NULL, this is some other
2655 * type of interesting event. The debugger may request a signal be delivered in
2656 * that case as well, however it will be deferred until it can be handled.
2659 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2661 struct proc *p = td->td_proc;
2665 PROC_LOCK_ASSERT(p, MA_OWNED);
2666 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2667 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2668 &p->p_mtx.lock_object, "Stopping for traced signal");
2672 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2673 td->td_dbgflags |= TDB_XSIG;
2674 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2675 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2677 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2680 * Ensure that, if we've been PT_KILLed, the
2681 * exit status reflects that. Another thread
2682 * may also be in ptracestop(), having just
2683 * received the SIGKILL, but this thread was
2684 * unsuspended first.
2686 td->td_dbgflags &= ~TDB_XSIG;
2687 td->td_xsig = SIGKILL;
2691 if (p->p_flag & P_SINGLE_EXIT &&
2692 !(td->td_dbgflags & TDB_EXIT)) {
2694 * Ignore ptrace stops except for thread exit
2695 * events when the process exits.
2697 td->td_dbgflags &= ~TDB_XSIG;
2703 * Make wait(2) work. Ensure that right after the
2704 * attach, the thread which was decided to become the
2705 * leader of attach gets reported to the waiter.
2706 * Otherwise, just avoid overwriting another thread's
2707 * assignment to p_xthread. If another thread has
2708 * already set p_xthread, the current thread will get
2709 * a chance to report itself upon the next iteration.
2711 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2712 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2713 p->p_xthread == NULL)) {
2718 * If we are on sleepqueue already,
2719 * let sleepqueue code decide if it
2720 * needs to go sleep after attach.
2722 if (td->td_wchan == NULL)
2723 td->td_dbgflags &= ~TDB_FSTP;
2725 p->p_flag2 &= ~P2_PTRACE_FSTP;
2726 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2727 sig_suspend_threads(td, p, 0);
2729 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2730 td->td_dbgflags &= ~TDB_STOPATFORK;
2733 td->td_dbgflags |= TDB_SSWITCH;
2734 thread_suspend_switch(td, p);
2735 td->td_dbgflags &= ~TDB_SSWITCH;
2736 if ((td->td_dbgflags & TDB_COREDUMPRQ) != 0) {
2738 ptrace_coredump(td);
2742 if (p->p_xthread == td)
2743 p->p_xthread = NULL;
2744 if (!(p->p_flag & P_TRACED))
2746 if (td->td_dbgflags & TDB_SUSPEND) {
2747 if (p->p_flag & P_SINGLE_EXIT)
2755 if (si != NULL && sig == td->td_xsig) {
2756 /* Parent wants us to take the original signal unchanged. */
2757 si->ksi_flags |= KSI_HEAD;
2758 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2760 } else if (td->td_xsig != 0) {
2762 * If parent wants us to take a new signal, then it will leave
2763 * it in td->td_xsig; otherwise we just look for signals again.
2765 ksiginfo_init(&ksi);
2766 ksi.ksi_signo = td->td_xsig;
2767 ksi.ksi_flags |= KSI_PTRACE;
2768 td2 = sigtd(p, td->td_xsig, false);
2769 tdsendsignal(p, td2, td->td_xsig, &ksi);
2774 return (td->td_xsig);
2778 reschedule_signals(struct proc *p, sigset_t block, int flags)
2783 bool fastblk, pslocked;
2785 PROC_LOCK_ASSERT(p, MA_OWNED);
2787 pslocked = (flags & SIGPROCMASK_PS_LOCKED) != 0;
2788 mtx_assert(&ps->ps_mtx, pslocked ? MA_OWNED : MA_NOTOWNED);
2789 if (SIGISEMPTY(p->p_siglist))
2791 SIGSETAND(block, p->p_siglist);
2792 fastblk = (flags & SIGPROCMASK_FASTBLK) != 0;
2793 SIG_FOREACH(sig, &block) {
2794 td = sigtd(p, sig, fastblk);
2797 * If sigtd() selected us despite sigfastblock is
2798 * blocking, do not activate AST or wake us, to avoid
2799 * loop in AST handler.
2801 if (fastblk && td == curthread)
2806 mtx_lock(&ps->ps_mtx);
2807 if (p->p_flag & P_TRACED ||
2808 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2809 !SIGISMEMBER(td->td_sigmask, sig))) {
2810 tdsigwakeup(td, sig, SIG_CATCH,
2811 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2815 mtx_unlock(&ps->ps_mtx);
2820 tdsigcleanup(struct thread *td)
2826 PROC_LOCK_ASSERT(p, MA_OWNED);
2828 sigqueue_flush(&td->td_sigqueue);
2829 if (p->p_numthreads == 1)
2833 * Since we cannot handle signals, notify signal post code
2834 * about this by filling the sigmask.
2836 * Also, if needed, wake up thread(s) that do not block the
2837 * same signals as the exiting thread, since the thread might
2838 * have been selected for delivery and woken up.
2840 SIGFILLSET(unblocked);
2841 SIGSETNAND(unblocked, td->td_sigmask);
2842 SIGFILLSET(td->td_sigmask);
2843 reschedule_signals(p, unblocked, 0);
2848 sigdeferstop_curr_flags(int cflags)
2851 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2852 (cflags & TDF_SBDRY) != 0);
2853 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2857 * Defer the delivery of SIGSTOP for the current thread, according to
2858 * the requested mode. Returns previous flags, which must be restored
2859 * by sigallowstop().
2861 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2862 * cleared by the current thread, which allow the lock-less read-only
2866 sigdeferstop_impl(int mode)
2872 cflags = sigdeferstop_curr_flags(td->td_flags);
2874 case SIGDEFERSTOP_NOP:
2877 case SIGDEFERSTOP_OFF:
2880 case SIGDEFERSTOP_SILENT:
2881 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2883 case SIGDEFERSTOP_EINTR:
2884 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2886 case SIGDEFERSTOP_ERESTART:
2887 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2890 panic("sigdeferstop: invalid mode %x", mode);
2893 if (cflags == nflags)
2894 return (SIGDEFERSTOP_VAL_NCHG);
2896 td->td_flags = (td->td_flags & ~cflags) | nflags;
2902 * Restores the STOP handling mode, typically permitting the delivery
2903 * of SIGSTOP for the current thread. This does not immediately
2904 * suspend if a stop was posted. Instead, the thread will suspend
2905 * either via ast() or a subsequent interruptible sleep.
2908 sigallowstop_impl(int prev)
2913 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2914 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2915 ("sigallowstop: incorrect previous mode %x", prev));
2917 cflags = sigdeferstop_curr_flags(td->td_flags);
2918 if (cflags != prev) {
2920 td->td_flags = (td->td_flags & ~cflags) | prev;
2929 SIGSTATUS_SBDRY_STOP,
2933 * The thread has signal "sig" pending. Figure out what to do with it:
2935 * _HANDLE -> the caller should handle the signal
2936 * _HANDLED -> handled internally, reload pending signal set
2937 * _IGNORE -> ignored, remove from the set of pending signals and try the
2938 * next pending signal
2939 * _SBDRY_STOP -> the signal should stop the thread but this is not
2940 * permitted in the current context
2942 static enum sigstatus
2943 sigprocess(struct thread *td, int sig)
2947 struct sigqueue *queue;
2951 KASSERT(_SIG_VALID(sig), ("%s: invalid signal %d", __func__, sig));
2955 mtx_assert(&ps->ps_mtx, MA_OWNED);
2956 PROC_LOCK_ASSERT(p, MA_OWNED);
2959 * We should allow pending but ignored signals below
2960 * only if there is sigwait() active, or P_TRACED was
2961 * on when they were posted.
2963 if (SIGISMEMBER(ps->ps_sigignore, sig) &&
2964 (p->p_flag & P_TRACED) == 0 &&
2965 (td->td_flags & TDF_SIGWAIT) == 0) {
2966 return (SIGSTATUS_IGNORE);
2969 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2971 * If traced, always stop.
2972 * Remove old signal from queue before the stop.
2973 * XXX shrug off debugger, it causes siginfo to
2976 queue = &td->td_sigqueue;
2977 ksiginfo_init(&ksi);
2978 if (sigqueue_get(queue, sig, &ksi) == 0) {
2979 queue = &p->p_sigqueue;
2980 sigqueue_get(queue, sig, &ksi);
2982 td->td_si = ksi.ksi_info;
2984 mtx_unlock(&ps->ps_mtx);
2985 sig = ptracestop(td, sig, &ksi);
2986 mtx_lock(&ps->ps_mtx);
2988 td->td_si.si_signo = 0;
2991 * Keep looking if the debugger discarded or
2992 * replaced the signal.
2995 return (SIGSTATUS_HANDLED);
2998 * If the signal became masked, re-queue it.
3000 if (SIGISMEMBER(td->td_sigmask, sig)) {
3001 ksi.ksi_flags |= KSI_HEAD;
3002 sigqueue_add(&p->p_sigqueue, sig, &ksi);
3003 return (SIGSTATUS_HANDLED);
3007 * If the traced bit got turned off, requeue the signal and
3008 * reload the set of pending signals. This ensures that p_sig*
3009 * and p_sigact are consistent.
3011 if ((p->p_flag & P_TRACED) == 0) {
3012 if ((ksi.ksi_flags & KSI_PTRACE) == 0) {
3013 ksi.ksi_flags |= KSI_HEAD;
3014 sigqueue_add(queue, sig, &ksi);
3016 return (SIGSTATUS_HANDLED);
3021 * Decide whether the signal should be returned.
3022 * Return the signal's number, or fall through
3023 * to clear it from the pending mask.
3025 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
3026 case (intptr_t)SIG_DFL:
3028 * Don't take default actions on system processes.
3030 if (p->p_pid <= 1) {
3033 * Are you sure you want to ignore SIGSEGV
3036 printf("Process (pid %lu) got signal %d\n",
3037 (u_long)p->p_pid, sig);
3039 return (SIGSTATUS_IGNORE);
3043 * If there is a pending stop signal to process with
3044 * default action, stop here, then clear the signal.
3045 * Traced or exiting processes should ignore stops.
3046 * Additionally, a member of an orphaned process group
3047 * should ignore tty stops.
3049 prop = sigprop(sig);
3050 if (prop & SIGPROP_STOP) {
3051 mtx_unlock(&ps->ps_mtx);
3052 if ((p->p_flag & (P_TRACED | P_WEXIT |
3053 P_SINGLE_EXIT)) != 0 || ((p->p_pgrp->
3054 pg_flags & PGRP_ORPHANED) != 0 &&
3055 (prop & SIGPROP_TTYSTOP) != 0)) {
3056 mtx_lock(&ps->ps_mtx);
3057 return (SIGSTATUS_IGNORE);
3059 if (TD_SBDRY_INTR(td)) {
3060 KASSERT((td->td_flags & TDF_SBDRY) != 0,
3061 ("lost TDF_SBDRY"));
3062 mtx_lock(&ps->ps_mtx);
3063 return (SIGSTATUS_SBDRY_STOP);
3065 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
3066 &p->p_mtx.lock_object, "Catching SIGSTOP");
3067 sigqueue_delete(&td->td_sigqueue, sig);
3068 sigqueue_delete(&p->p_sigqueue, sig);
3069 p->p_flag |= P_STOPPED_SIG;
3072 sig_suspend_threads(td, p, 0);
3073 thread_suspend_switch(td, p);
3075 mtx_lock(&ps->ps_mtx);
3076 return (SIGSTATUS_HANDLED);
3077 } else if ((prop & SIGPROP_IGNORE) != 0 &&
3078 (td->td_flags & TDF_SIGWAIT) == 0) {
3080 * Default action is to ignore; drop it if
3081 * not in kern_sigtimedwait().
3083 return (SIGSTATUS_IGNORE);
3085 return (SIGSTATUS_HANDLE);
3088 case (intptr_t)SIG_IGN:
3089 if ((td->td_flags & TDF_SIGWAIT) == 0)
3090 return (SIGSTATUS_IGNORE);
3092 return (SIGSTATUS_HANDLE);
3096 * This signal has an action, let postsig() process it.
3098 return (SIGSTATUS_HANDLE);
3103 * If the current process has received a signal (should be caught or cause
3104 * termination, should interrupt current syscall), return the signal number.
3105 * Stop signals with default action are processed immediately, then cleared;
3106 * they aren't returned. This is checked after each entry to the system for
3107 * a syscall or trap (though this can usually be done without calling
3108 * issignal by checking the pending signal masks in cursig.) The normal call
3111 * while (sig = cursig(curthread))
3115 issignal(struct thread *td)
3118 sigset_t sigpending;
3122 PROC_LOCK_ASSERT(p, MA_OWNED);
3125 sigpending = td->td_sigqueue.sq_signals;
3126 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
3127 SIGSETNAND(sigpending, td->td_sigmask);
3129 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
3130 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
3131 SIG_STOPSIGMASK(sigpending);
3132 if (SIGISEMPTY(sigpending)) /* no signal to send */
3136 * Do fast sigblock if requested by usermode. Since
3137 * we do know that there was a signal pending at this
3138 * point, set the FAST_SIGBLOCK_PEND as indicator for
3139 * usermode to perform a dummy call to
3140 * FAST_SIGBLOCK_UNBLOCK, which causes immediate
3141 * delivery of postponed pending signal.
3143 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
3144 if (td->td_sigblock_val != 0)
3145 SIGSETNAND(sigpending, fastblock_mask);
3146 if (SIGISEMPTY(sigpending)) {
3147 td->td_pflags |= TDP_SIGFASTPENDING;
3152 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
3153 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
3154 SIGISMEMBER(sigpending, SIGSTOP)) {
3156 * If debugger just attached, always consume
3157 * SIGSTOP from ptrace(PT_ATTACH) first, to
3158 * execute the debugger attach ritual in
3161 td->td_dbgflags |= TDB_FSTP;
3162 SIGEMPTYSET(sigpending);
3163 SIGADDSET(sigpending, SIGSTOP);
3166 SIG_FOREACH(sig, &sigpending) {
3167 switch (sigprocess(td, sig)) {
3168 case SIGSTATUS_HANDLE:
3170 case SIGSTATUS_HANDLED:
3172 case SIGSTATUS_IGNORE:
3173 sigqueue_delete(&td->td_sigqueue, sig);
3174 sigqueue_delete(&p->p_sigqueue, sig);
3176 case SIGSTATUS_SBDRY_STOP:
3185 thread_stopped(struct proc *p)
3189 PROC_LOCK_ASSERT(p, MA_OWNED);
3190 PROC_SLOCK_ASSERT(p, MA_OWNED);
3194 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
3196 p->p_flag &= ~P_WAITED;
3197 PROC_LOCK(p->p_pptr);
3198 childproc_stopped(p, (p->p_flag & P_TRACED) ?
3199 CLD_TRAPPED : CLD_STOPPED);
3200 PROC_UNLOCK(p->p_pptr);
3206 * Take the action for the specified signal
3207 * from the current set of pending signals.
3217 sigset_t returnmask;
3219 KASSERT(sig != 0, ("postsig"));
3223 PROC_LOCK_ASSERT(p, MA_OWNED);
3225 mtx_assert(&ps->ps_mtx, MA_OWNED);
3226 ksiginfo_init(&ksi);
3227 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3228 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3230 ksi.ksi_signo = sig;
3231 if (ksi.ksi_code == SI_TIMER)
3232 itimer_accept(p, ksi.ksi_timerid, &ksi);
3233 action = ps->ps_sigact[_SIG_IDX(sig)];
3235 if (KTRPOINT(td, KTR_PSIG))
3236 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3237 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3240 if (action == SIG_DFL) {
3242 * Default action, where the default is to kill
3243 * the process. (Other cases were ignored above.)
3245 mtx_unlock(&ps->ps_mtx);
3246 proc_td_siginfo_capture(td, &ksi.ksi_info);
3251 * If we get here, the signal must be caught.
3253 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3254 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3255 ("postsig action: blocked sig %d", sig));
3258 * Set the new mask value and also defer further
3259 * occurrences of this signal.
3261 * Special case: user has done a sigsuspend. Here the
3262 * current mask is not of interest, but rather the
3263 * mask from before the sigsuspend is what we want
3264 * restored after the signal processing is completed.
3266 if (td->td_pflags & TDP_OLDMASK) {
3267 returnmask = td->td_oldsigmask;
3268 td->td_pflags &= ~TDP_OLDMASK;
3270 returnmask = td->td_sigmask;
3272 if (p->p_sig == sig) {
3275 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3276 postsig_done(sig, td, ps);
3282 sig_ast_checksusp(struct thread *td)
3284 struct proc *p __diagused;
3288 PROC_LOCK_ASSERT(p, MA_OWNED);
3290 if ((td->td_flags & TDF_NEEDSUSPCHK) == 0)
3293 ret = thread_suspend_check(1);
3294 MPASS(ret == 0 || ret == EINTR || ret == ERESTART);
3299 sig_ast_needsigchk(struct thread *td)
3306 PROC_LOCK_ASSERT(p, MA_OWNED);
3308 if ((td->td_flags & TDF_NEEDSIGCHK) == 0)
3312 mtx_lock(&ps->ps_mtx);
3315 mtx_unlock(&ps->ps_mtx);
3316 KASSERT((td->td_flags & TDF_SBDRY) != 0, ("lost TDF_SBDRY"));
3317 KASSERT(TD_SBDRY_INTR(td),
3318 ("lost TDF_SERESTART of TDF_SEINTR"));
3319 KASSERT((td->td_flags & (TDF_SEINTR | TDF_SERESTART)) !=
3320 (TDF_SEINTR | TDF_SERESTART),
3321 ("both TDF_SEINTR and TDF_SERESTART"));
3322 ret = TD_SBDRY_ERRNO(td);
3323 } else if (sig != 0) {
3324 ret = SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR : ERESTART;
3325 mtx_unlock(&ps->ps_mtx);
3327 mtx_unlock(&ps->ps_mtx);
3332 * Do not go into sleep if this thread was the ptrace(2)
3333 * attach leader. cursig() consumed SIGSTOP from PT_ATTACH,
3334 * but we usually act on the signal by interrupting sleep, and
3335 * should do that here as well.
3337 if ((td->td_dbgflags & TDB_FSTP) != 0) {
3340 td->td_dbgflags &= ~TDB_FSTP;
3354 if ((td->td_flags & (TDF_NEEDSIGCHK | TDF_NEEDSUSPCHK)) == 0)
3360 ret = sig_ast_checksusp(td);
3362 ret = sig_ast_needsigchk(td);
3368 curproc_sigkilled(void)
3376 if ((td->td_flags & TDF_NEEDSIGCHK) == 0)
3382 mtx_lock(&ps->ps_mtx);
3383 res = SIGISMEMBER(td->td_sigqueue.sq_signals, SIGKILL) ||
3384 SIGISMEMBER(p->p_sigqueue.sq_signals, SIGKILL);
3385 mtx_unlock(&ps->ps_mtx);
3391 proc_wkilled(struct proc *p)
3394 PROC_LOCK_ASSERT(p, MA_OWNED);
3395 if ((p->p_flag & P_WKILLED) == 0) {
3396 p->p_flag |= P_WKILLED;
3398 * Notify swapper that there is a process to swap in.
3399 * The notification is racy, at worst it would take 10
3400 * seconds for the swapper process to notice.
3402 if ((p->p_flag & (P_INMEM | P_SWAPPINGIN)) == 0)
3408 * Kill the current process for stated reason.
3411 killproc(struct proc *p, const char *why)
3414 PROC_LOCK_ASSERT(p, MA_OWNED);
3415 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3417 log(LOG_ERR, "pid %d (%s), jid %d, uid %d, was killed: %s\n",
3418 p->p_pid, p->p_comm, p->p_ucred->cr_prison->pr_id,
3419 p->p_ucred->cr_uid, why);
3421 kern_psignal(p, SIGKILL);
3425 * Force the current process to exit with the specified signal, dumping core
3426 * if appropriate. We bypass the normal tests for masked and caught signals,
3427 * allowing unrecoverable failures to terminate the process without changing
3428 * signal state. Mark the accounting record with the signal termination.
3429 * If dumping core, save the signal number for the debugger. Calls exit and
3433 sigexit(struct thread *td, int sig)
3435 struct proc *p = td->td_proc;
3437 PROC_LOCK_ASSERT(p, MA_OWNED);
3438 p->p_acflag |= AXSIG;
3440 * We must be single-threading to generate a core dump. This
3441 * ensures that the registers in the core file are up-to-date.
3442 * Also, the ELF dump handler assumes that the thread list doesn't
3443 * change out from under it.
3445 * XXX If another thread attempts to single-thread before us
3446 * (e.g. via fork()), we won't get a dump at all.
3448 if ((sigprop(sig) & SIGPROP_CORE) &&
3449 thread_single(p, SINGLE_NO_EXIT) == 0) {
3452 * Log signals which would cause core dumps
3453 * (Log as LOG_INFO to appease those who don't want
3455 * XXX : Todo, as well as euid, write out ruid too
3456 * Note that coredump() drops proc lock.
3458 if (coredump(td) == 0)
3460 if (kern_logsigexit)
3462 "pid %d (%s), jid %d, uid %d: exited on "
3463 "signal %d%s\n", p->p_pid, p->p_comm,
3464 p->p_ucred->cr_prison->pr_id,
3465 td->td_ucred->cr_uid,
3467 sig & WCOREFLAG ? " (core dumped)" : "");
3475 * Send queued SIGCHLD to parent when child process's state
3479 sigparent(struct proc *p, int reason, int status)
3481 PROC_LOCK_ASSERT(p, MA_OWNED);
3482 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3484 if (p->p_ksi != NULL) {
3485 p->p_ksi->ksi_signo = SIGCHLD;
3486 p->p_ksi->ksi_code = reason;
3487 p->p_ksi->ksi_status = status;
3488 p->p_ksi->ksi_pid = p->p_pid;
3489 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3490 if (KSI_ONQ(p->p_ksi))
3493 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3497 childproc_jobstate(struct proc *p, int reason, int sig)
3501 PROC_LOCK_ASSERT(p, MA_OWNED);
3502 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3505 * Wake up parent sleeping in kern_wait(), also send
3506 * SIGCHLD to parent, but SIGCHLD does not guarantee
3507 * that parent will awake, because parent may masked
3510 p->p_pptr->p_flag |= P_STATCHILD;
3513 ps = p->p_pptr->p_sigacts;
3514 mtx_lock(&ps->ps_mtx);
3515 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3516 mtx_unlock(&ps->ps_mtx);
3517 sigparent(p, reason, sig);
3519 mtx_unlock(&ps->ps_mtx);
3523 childproc_stopped(struct proc *p, int reason)
3526 childproc_jobstate(p, reason, p->p_xsig);
3530 childproc_continued(struct proc *p)
3532 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3536 childproc_exited(struct proc *p)
3540 if (WCOREDUMP(p->p_xsig)) {
3541 reason = CLD_DUMPED;
3542 status = WTERMSIG(p->p_xsig);
3543 } else if (WIFSIGNALED(p->p_xsig)) {
3544 reason = CLD_KILLED;
3545 status = WTERMSIG(p->p_xsig);
3547 reason = CLD_EXITED;
3548 status = p->p_xexit;
3551 * XXX avoid calling wakeup(p->p_pptr), the work is
3554 sigparent(p, reason, status);
3557 #define MAX_NUM_CORE_FILES 100000
3558 #ifndef NUM_CORE_FILES
3559 #define NUM_CORE_FILES 5
3561 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3562 static int num_cores = NUM_CORE_FILES;
3565 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3570 new_val = num_cores;
3571 error = sysctl_handle_int(oidp, &new_val, 0, req);
3572 if (error != 0 || req->newptr == NULL)
3574 if (new_val > MAX_NUM_CORE_FILES)
3575 new_val = MAX_NUM_CORE_FILES;
3578 num_cores = new_val;
3581 SYSCTL_PROC(_debug, OID_AUTO, ncores,
3582 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, sizeof(int),
3583 sysctl_debug_num_cores_check, "I",
3584 "Maximum number of generated process corefiles while using index format");
3586 #define GZIP_SUFFIX ".gz"
3587 #define ZSTD_SUFFIX ".zst"
3589 int compress_user_cores = 0;
3592 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3596 val = compress_user_cores;
3597 error = sysctl_handle_int(oidp, &val, 0, req);
3598 if (error != 0 || req->newptr == NULL)
3600 if (val != 0 && !compressor_avail(val))
3602 compress_user_cores = val;
3605 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores,
3606 CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, 0, sizeof(int),
3607 sysctl_compress_user_cores, "I",
3608 "Enable compression of user corefiles ("
3609 __XSTRING(COMPRESS_GZIP) " = gzip, "
3610 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3612 int compress_user_cores_level = 6;
3613 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3614 &compress_user_cores_level, 0,
3615 "Corefile compression level");
3618 * Protect the access to corefilename[] by allproc_lock.
3620 #define corefilename_lock allproc_lock
3622 static char corefilename[MAXPATHLEN] = {"%N.core"};
3623 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3626 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3630 sx_xlock(&corefilename_lock);
3631 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3633 sx_xunlock(&corefilename_lock);
3637 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3638 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3639 "Process corefile name format string");
3642 vnode_close_locked(struct thread *td, struct vnode *vp)
3646 vn_close(vp, FWRITE, td->td_ucred, td);
3650 * If the core format has a %I in it, then we need to check
3651 * for existing corefiles before defining a name.
3652 * To do this we iterate over 0..ncores to find a
3653 * non-existing core file name to use. If all core files are
3654 * already used we choose the oldest one.
3657 corefile_open_last(struct thread *td, char *name, int indexpos,
3658 int indexlen, int ncores, struct vnode **vpp)
3660 struct vnode *oldvp, *nextvp, *vp;
3662 struct nameidata nd;
3663 int error, i, flags, oflags, cmode;
3665 struct timespec lasttime;
3667 nextvp = oldvp = NULL;
3668 cmode = S_IRUSR | S_IWUSR;
3669 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3670 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3672 for (i = 0; i < ncores; i++) {
3673 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3675 ch = name[indexpos + indexlen];
3676 (void)snprintf(name + indexpos, indexlen + 1, "%.*u", indexlen,
3678 name[indexpos + indexlen] = ch;
3680 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3681 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3687 NDFREE(&nd, NDF_ONLY_PNBUF);
3688 if ((flags & O_CREAT) == O_CREAT) {
3693 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
3695 vnode_close_locked(td, vp);
3699 if (oldvp == NULL ||
3700 lasttime.tv_sec > vattr.va_mtime.tv_sec ||
3701 (lasttime.tv_sec == vattr.va_mtime.tv_sec &&
3702 lasttime.tv_nsec >= vattr.va_mtime.tv_nsec)) {
3704 vn_close(oldvp, FWRITE, td->td_ucred, td);
3707 lasttime = vattr.va_mtime;
3709 vnode_close_locked(td, vp);
3713 if (oldvp != NULL) {
3714 if (nextvp == NULL) {
3715 if ((td->td_proc->p_flag & P_SUGID) != 0) {
3717 vn_close(oldvp, FWRITE, td->td_ucred, td);
3720 error = vn_lock(nextvp, LK_EXCLUSIVE);
3722 vn_close(nextvp, FWRITE, td->td_ucred,
3728 vn_close(oldvp, FWRITE, td->td_ucred, td);
3733 vnode_close_locked(td, oldvp);
3742 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3743 * Expand the name described in corefilename, using name, uid, and pid
3744 * and open/create core file.
3745 * corefilename is a printf-like string, with three format specifiers:
3746 * %N name of process ("name")
3747 * %P process id (pid)
3749 * For example, "%N.core" is the default; they can be disabled completely
3750 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3751 * This is controlled by the sysctl variable kern.corefile (see above).
3754 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3755 int compress, int signum, struct vnode **vpp, char **namep)
3758 struct nameidata nd;
3760 char *hostname, *name;
3761 int cmode, error, flags, i, indexpos, indexlen, oflags, ncores;
3764 format = corefilename;
3765 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3769 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3770 sx_slock(&corefilename_lock);
3771 for (i = 0; format[i] != '\0'; i++) {
3772 switch (format[i]) {
3773 case '%': /* Format character */
3775 switch (format[i]) {
3777 sbuf_putc(&sb, '%');
3779 case 'H': /* hostname */
3780 if (hostname == NULL) {
3781 hostname = malloc(MAXHOSTNAMELEN,
3784 getcredhostname(td->td_ucred, hostname,
3786 sbuf_printf(&sb, "%s", hostname);
3788 case 'I': /* autoincrementing index */
3789 if (indexpos != -1) {
3790 sbuf_printf(&sb, "%%I");
3794 indexpos = sbuf_len(&sb);
3795 sbuf_printf(&sb, "%u", ncores - 1);
3796 indexlen = sbuf_len(&sb) - indexpos;
3798 case 'N': /* process name */
3799 sbuf_printf(&sb, "%s", comm);
3801 case 'P': /* process id */
3802 sbuf_printf(&sb, "%u", pid);
3804 case 'S': /* signal number */
3805 sbuf_printf(&sb, "%i", signum);
3807 case 'U': /* user id */
3808 sbuf_printf(&sb, "%u", uid);
3812 "Unknown format character %c in "
3813 "corename `%s'\n", format[i], format);
3818 sbuf_putc(&sb, format[i]);
3822 sx_sunlock(&corefilename_lock);
3823 free(hostname, M_TEMP);
3824 if (compress == COMPRESS_GZIP)
3825 sbuf_printf(&sb, GZIP_SUFFIX);
3826 else if (compress == COMPRESS_ZSTD)
3827 sbuf_printf(&sb, ZSTD_SUFFIX);
3828 if (sbuf_error(&sb) != 0) {
3829 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3830 "long\n", (long)pid, comm, (u_long)uid);
3838 if (indexpos != -1) {
3839 error = corefile_open_last(td, name, indexpos, indexlen, ncores,
3843 "pid %d (%s), uid (%u): Path `%s' failed "
3844 "on initial open test, error = %d\n",
3845 pid, comm, uid, name, error);
3848 cmode = S_IRUSR | S_IWUSR;
3849 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3850 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3851 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3852 if ((td->td_proc->p_flag & P_SUGID) != 0)
3855 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3856 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3860 NDFREE(&nd, NDF_ONLY_PNBUF);
3866 audit_proc_coredump(td, name, error);
3876 * Dump a process' core. The main routine does some
3877 * policy checking, and creates the name of the coredump;
3878 * then it passes on a vnode and a size limit to the process-specific
3879 * coredump routine if there is one; if there _is not_ one, it returns
3880 * ENOSYS; otherwise it returns the error from the process-specific routine.
3884 coredump(struct thread *td)
3886 struct proc *p = td->td_proc;
3887 struct ucred *cred = td->td_ucred;
3891 size_t fullpathsize;
3892 int error, error1, locked;
3893 char *name; /* name of corefile */
3896 char *fullpath, *freepath = NULL;
3899 PROC_LOCK_ASSERT(p, MA_OWNED);
3900 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3902 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3903 (p->p_flag2 & P2_NOTRACE) != 0) {
3909 * Note that the bulk of limit checking is done after
3910 * the corefile is created. The exception is if the limit
3911 * for corefiles is 0, in which case we don't bother
3912 * creating the corefile at all. This layout means that
3913 * a corefile is truncated instead of not being created,
3914 * if it is larger than the limit.
3916 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3917 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3923 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3924 compress_user_cores, p->p_sig, &vp, &name);
3929 * Don't dump to non-regular files or files with links.
3930 * Do not dump into system files. Effective user must own the corefile.
3932 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3933 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0 ||
3934 vattr.va_uid != cred->cr_uid) {
3942 /* Postpone other writers, including core dumps of other processes. */
3943 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3945 lf.l_whence = SEEK_SET;
3948 lf.l_type = F_WRLCK;
3949 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3953 if (set_core_nodump_flag)
3954 vattr.va_flags = UF_NODUMP;
3955 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3956 VOP_SETATTR(vp, &vattr, cred);
3959 p->p_acflag |= ACORE;
3962 if (p->p_sysent->sv_coredump != NULL) {
3963 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3969 lf.l_type = F_UNLCK;
3970 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3972 vn_rangelock_unlock(vp, rl_cookie);
3975 * Notify the userland helper that a process triggered a core dump.
3976 * This allows the helper to run an automated debugging session.
3978 if (error != 0 || coredump_devctl == 0)
3980 sb = sbuf_new_auto();
3981 if (vn_fullpath_global(p->p_textvp, &fullpath, &freepath) != 0)
3983 sbuf_printf(sb, "comm=\"");
3984 devctl_safe_quote_sb(sb, fullpath);
3985 free(freepath, M_TEMP);
3986 sbuf_printf(sb, "\" core=\"");
3989 * We can't lookup core file vp directly. When we're replacing a core, and
3990 * other random times, we flush the name cache, so it will fail. Instead,
3991 * if the path of the core is relative, add the current dir in front if it.
3993 if (name[0] != '/') {
3994 fullpathsize = MAXPATHLEN;
3995 freepath = malloc(fullpathsize, M_TEMP, M_WAITOK);
3996 if (vn_getcwd(freepath, &fullpath, &fullpathsize) != 0) {
3997 free(freepath, M_TEMP);
4000 devctl_safe_quote_sb(sb, fullpath);
4001 free(freepath, M_TEMP);
4004 devctl_safe_quote_sb(sb, name);
4005 sbuf_printf(sb, "\"");
4006 if (sbuf_finish(sb) == 0)
4007 devctl_notify("kernel", "signal", "coredump", sbuf_data(sb));
4011 error1 = vn_close(vp, FWRITE, cred, td);
4015 audit_proc_coredump(td, name, error);
4022 * Nonexistent system call-- signal process (may want to handle it). Flag
4023 * error in case process won't see signal immediately (blocked or ignored).
4025 #ifndef _SYS_SYSPROTO_H_
4032 nosys(struct thread *td, struct nosys_args *args)
4039 tdsignal(td, SIGSYS);
4041 if (kern_lognosys == 1 || kern_lognosys == 3) {
4042 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
4045 if (kern_lognosys == 2 || kern_lognosys == 3 ||
4046 (p->p_pid == 1 && (kern_lognosys & 3) == 0)) {
4047 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
4054 * Send a SIGIO or SIGURG signal to a process or process group using stored
4055 * credentials rather than those of the current process.
4058 pgsigio(struct sigio **sigiop, int sig, int checkctty)
4061 struct sigio *sigio;
4063 ksiginfo_init(&ksi);
4064 ksi.ksi_signo = sig;
4065 ksi.ksi_code = SI_KERNEL;
4069 if (sigio == NULL) {
4073 if (sigio->sio_pgid > 0) {
4074 PROC_LOCK(sigio->sio_proc);
4075 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
4076 kern_psignal(sigio->sio_proc, sig);
4077 PROC_UNLOCK(sigio->sio_proc);
4078 } else if (sigio->sio_pgid < 0) {
4081 PGRP_LOCK(sigio->sio_pgrp);
4082 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
4084 if (p->p_state == PRS_NORMAL &&
4085 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
4086 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
4087 kern_psignal(p, sig);
4090 PGRP_UNLOCK(sigio->sio_pgrp);
4096 filt_sigattach(struct knote *kn)
4098 struct proc *p = curproc;
4100 kn->kn_ptr.p_proc = p;
4101 kn->kn_flags |= EV_CLEAR; /* automatically set */
4103 knlist_add(p->p_klist, kn, 0);
4109 filt_sigdetach(struct knote *kn)
4111 struct proc *p = kn->kn_ptr.p_proc;
4113 knlist_remove(p->p_klist, kn, 0);
4117 * signal knotes are shared with proc knotes, so we apply a mask to
4118 * the hint in order to differentiate them from process hints. This
4119 * could be avoided by using a signal-specific knote list, but probably
4120 * isn't worth the trouble.
4123 filt_signal(struct knote *kn, long hint)
4126 if (hint & NOTE_SIGNAL) {
4127 hint &= ~NOTE_SIGNAL;
4129 if (kn->kn_id == hint)
4132 return (kn->kn_data != 0);
4140 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
4141 refcount_init(&ps->ps_refcnt, 1);
4142 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
4147 sigacts_free(struct sigacts *ps)
4150 if (refcount_release(&ps->ps_refcnt) == 0)
4152 mtx_destroy(&ps->ps_mtx);
4153 free(ps, M_SUBPROC);
4157 sigacts_hold(struct sigacts *ps)
4160 refcount_acquire(&ps->ps_refcnt);
4165 sigacts_copy(struct sigacts *dest, struct sigacts *src)
4168 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
4169 mtx_lock(&src->ps_mtx);
4170 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
4171 mtx_unlock(&src->ps_mtx);
4175 sigacts_shared(struct sigacts *ps)
4178 return (ps->ps_refcnt > 1);
4182 sig_drop_caught(struct proc *p)
4188 PROC_LOCK_ASSERT(p, MA_OWNED);
4189 mtx_assert(&ps->ps_mtx, MA_OWNED);
4190 SIG_FOREACH(sig, &ps->ps_sigcatch) {
4192 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
4193 sigqueue_delete_proc(p, sig);
4198 sigfastblock_failed(struct thread *td, bool sendsig, bool write)
4203 * Prevent further fetches and SIGSEGVs, allowing thread to
4204 * issue syscalls despite corruption.
4206 sigfastblock_clear(td);
4210 ksiginfo_init_trap(&ksi);
4211 ksi.ksi_signo = SIGSEGV;
4212 ksi.ksi_code = write ? SEGV_ACCERR : SEGV_MAPERR;
4213 ksi.ksi_addr = td->td_sigblock_ptr;
4214 trapsignal(td, &ksi);
4218 sigfastblock_fetch_sig(struct thread *td, bool sendsig, uint32_t *valp)
4222 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0)
4224 if (fueword32((void *)td->td_sigblock_ptr, &res) == -1) {
4225 sigfastblock_failed(td, sendsig, false);
4229 td->td_sigblock_val = res & ~SIGFASTBLOCK_FLAGS;
4234 sigfastblock_resched(struct thread *td, bool resched)
4241 reschedule_signals(p, td->td_sigmask, 0);
4245 td->td_flags |= TDF_ASTPENDING | TDF_NEEDSIGCHK;
4250 sys_sigfastblock(struct thread *td, struct sigfastblock_args *uap)
4259 case SIGFASTBLOCK_SETPTR:
4260 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
4264 if (((uintptr_t)(uap->ptr) & (sizeof(uint32_t) - 1)) != 0) {
4268 td->td_pflags |= TDP_SIGFASTBLOCK;
4269 td->td_sigblock_ptr = uap->ptr;
4272 case SIGFASTBLOCK_UNBLOCK:
4273 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) {
4279 res = casueword32(td->td_sigblock_ptr,
4280 SIGFASTBLOCK_PEND, &oldval, 0);
4283 sigfastblock_failed(td, false, true);
4289 if (oldval != SIGFASTBLOCK_PEND) {
4293 error = thread_check_susp(td, false);
4301 * td_sigblock_val is cleared there, but not on a
4302 * syscall exit. The end effect is that a single
4303 * interruptible sleep, while user sigblock word is
4304 * set, might return EINTR or ERESTART to usermode
4305 * without delivering signal. All further sleeps,
4306 * until userspace clears the word and does
4307 * sigfastblock(UNBLOCK), observe current word and no
4308 * longer get interrupted. It is slight
4309 * non-conformance, with alternative to have read the
4310 * sigblock word on each syscall entry.
4312 td->td_sigblock_val = 0;
4315 * Rely on normal ast mechanism to deliver pending
4316 * signals to current thread. But notify others about
4319 sigfastblock_resched(td, error == 0 && p->p_numthreads != 1);
4323 case SIGFASTBLOCK_UNSETPTR:
4324 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) {
4328 if (!sigfastblock_fetch_sig(td, false, &oldval)) {
4332 if (oldval != 0 && oldval != SIGFASTBLOCK_PEND) {
4336 sigfastblock_clear(td);
4347 sigfastblock_clear(struct thread *td)
4351 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0)
4353 td->td_sigblock_val = 0;
4354 resched = (td->td_pflags & TDP_SIGFASTPENDING) != 0 ||
4356 td->td_pflags &= ~(TDP_SIGFASTBLOCK | TDP_SIGFASTPENDING);
4357 sigfastblock_resched(td, resched);
4361 sigfastblock_fetch(struct thread *td)
4365 (void)sigfastblock_fetch_sig(td, true, &val);
4369 sigfastblock_setpend1(struct thread *td)
4374 if ((td->td_pflags & TDP_SIGFASTPENDING) == 0)
4376 res = fueword32((void *)td->td_sigblock_ptr, &oldval);
4378 sigfastblock_failed(td, true, false);
4382 res = casueword32(td->td_sigblock_ptr, oldval, &oldval,
4383 oldval | SIGFASTBLOCK_PEND);
4385 sigfastblock_failed(td, true, true);
4389 td->td_sigblock_val = oldval & ~SIGFASTBLOCK_FLAGS;
4390 td->td_pflags &= ~TDP_SIGFASTPENDING;
4394 if (thread_check_susp(td, false) != 0)
4400 sigfastblock_setpend(struct thread *td, bool resched)
4404 sigfastblock_setpend1(td);
4408 reschedule_signals(p, fastblock_mask, SIGPROCMASK_FASTBLK);