2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
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9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
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13 * modification, are permitted provided that the following conditions
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33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
42 #include "opt_ktrace.h"
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
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)
1005 * Reset caught signals. Held signals remain held
1006 * through td_sigmask (unless they were caught,
1007 * and are now ignored by default).
1009 PROC_LOCK_ASSERT(p, MA_OWNED);
1011 mtx_lock(&ps->ps_mtx);
1015 * Reset stack state to the user stack.
1016 * Clear set of signals caught on the signal stack.
1019 MPASS(td->td_proc == p);
1020 td->td_sigstk.ss_flags = SS_DISABLE;
1021 td->td_sigstk.ss_size = 0;
1022 td->td_sigstk.ss_sp = 0;
1023 td->td_pflags &= ~TDP_ALTSTACK;
1025 * Reset no zombies if child dies flag as Solaris does.
1027 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1028 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1029 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1030 mtx_unlock(&ps->ps_mtx);
1034 * kern_sigprocmask()
1036 * Manipulate signal mask.
1039 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1042 sigset_t new_block, oset1;
1047 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1048 PROC_LOCK_ASSERT(p, MA_OWNED);
1051 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1052 ? MA_OWNED : MA_NOTOWNED);
1054 *oset = td->td_sigmask;
1061 oset1 = td->td_sigmask;
1062 SIGSETOR(td->td_sigmask, *set);
1063 new_block = td->td_sigmask;
1064 SIGSETNAND(new_block, oset1);
1067 SIGSETNAND(td->td_sigmask, *set);
1072 oset1 = td->td_sigmask;
1073 if (flags & SIGPROCMASK_OLD)
1074 SIGSETLO(td->td_sigmask, *set);
1076 td->td_sigmask = *set;
1077 new_block = td->td_sigmask;
1078 SIGSETNAND(new_block, oset1);
1087 * The new_block set contains signals that were not previously
1088 * blocked, but are blocked now.
1090 * In case we block any signal that was not previously blocked
1091 * for td, and process has the signal pending, try to schedule
1092 * signal delivery to some thread that does not block the
1093 * signal, possibly waking it up.
1095 if (p->p_numthreads != 1)
1096 reschedule_signals(p, new_block, flags);
1100 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1105 #ifndef _SYS_SYSPROTO_H_
1106 struct sigprocmask_args {
1108 const sigset_t *set;
1113 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1116 sigset_t *setp, *osetp;
1119 setp = (uap->set != NULL) ? &set : NULL;
1120 osetp = (uap->oset != NULL) ? &oset : NULL;
1122 error = copyin(uap->set, setp, sizeof(set));
1126 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1127 if (osetp && !error) {
1128 error = copyout(osetp, uap->oset, sizeof(oset));
1133 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1134 #ifndef _SYS_SYSPROTO_H_
1135 struct osigprocmask_args {
1141 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1146 OSIG2SIG(uap->mask, set);
1147 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1148 SIG2OSIG(oset, td->td_retval[0]);
1151 #endif /* COMPAT_43 */
1154 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1160 error = copyin(uap->set, &set, sizeof(set));
1162 td->td_retval[0] = error;
1166 error = kern_sigtimedwait(td, set, &ksi, NULL);
1169 * sigwait() function shall not return EINTR, but
1170 * the syscall does. Non-ancient libc provides the
1171 * wrapper which hides EINTR. Otherwise, EINTR return
1172 * is used by libthr to handle required cancellation
1173 * point in the sigwait().
1175 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1177 td->td_retval[0] = error;
1181 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1182 td->td_retval[0] = error;
1187 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1190 struct timespec *timeout;
1196 error = copyin(uap->timeout, &ts, sizeof(ts));
1204 error = copyin(uap->set, &set, sizeof(set));
1208 error = kern_sigtimedwait(td, set, &ksi, timeout);
1213 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1216 td->td_retval[0] = ksi.ksi_signo;
1221 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1227 error = copyin(uap->set, &set, sizeof(set));
1231 error = kern_sigtimedwait(td, set, &ksi, NULL);
1236 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1239 td->td_retval[0] = ksi.ksi_signo;
1244 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1248 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1252 thr->td_si.si_signo = 0;
1257 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1258 struct timespec *timeout)
1261 sigset_t saved_mask, new_block;
1263 int error, sig, timo, timevalid = 0;
1264 struct timespec rts, ets, ts;
1274 /* Ensure the sigfastblock value is up to date. */
1275 sigfastblock_fetch(td);
1277 if (timeout != NULL) {
1278 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1280 getnanouptime(&rts);
1281 timespecadd(&rts, timeout, &ets);
1285 /* Some signals can not be waited for. */
1286 SIG_CANTMASK(waitset);
1289 saved_mask = td->td_sigmask;
1290 SIGSETNAND(td->td_sigmask, waitset);
1291 if ((p->p_sysent->sv_flags & SV_SIG_DISCIGN) != 0 ||
1292 !kern_sig_discard_ign) {
1294 td->td_flags |= TDF_SIGWAIT;
1298 mtx_lock(&ps->ps_mtx);
1300 mtx_unlock(&ps->ps_mtx);
1301 KASSERT(sig >= 0, ("sig %d", sig));
1302 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1303 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1304 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1314 * POSIX says this must be checked after looking for pending
1317 if (timeout != NULL) {
1322 getnanouptime(&rts);
1323 if (timespeccmp(&rts, &ets, >=)) {
1327 timespecsub(&ets, &rts, &ts);
1328 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1339 error = msleep(&p->p_sigacts, &p->p_mtx, PPAUSE | PCATCH,
1342 /* The syscalls can not be restarted. */
1343 if (error == ERESTART)
1346 /* We will calculate timeout by ourself. */
1347 if (timeout != NULL && error == EAGAIN)
1351 * If PTRACE_SCE or PTRACE_SCX were set after
1352 * userspace entered the syscall, return spurious
1353 * EINTR after wait was done. Only do this as last
1354 * resort after rechecking for possible queued signals
1355 * and expired timeouts.
1357 if (error == 0 && (p->p_ptevents & PTRACE_SYSCALL) != 0)
1361 td->td_flags &= ~TDF_SIGWAIT;
1364 new_block = saved_mask;
1365 SIGSETNAND(new_block, td->td_sigmask);
1366 td->td_sigmask = saved_mask;
1368 * Fewer signals can be delivered to us, reschedule signal
1371 if (p->p_numthreads != 1)
1372 reschedule_signals(p, new_block, 0);
1375 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1377 if (ksi->ksi_code == SI_TIMER)
1378 itimer_accept(p, ksi->ksi_timerid, ksi);
1381 if (KTRPOINT(td, KTR_PSIG)) {
1384 mtx_lock(&ps->ps_mtx);
1385 action = ps->ps_sigact[_SIG_IDX(sig)];
1386 mtx_unlock(&ps->ps_mtx);
1387 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1390 if (sig == SIGKILL) {
1391 proc_td_siginfo_capture(td, &ksi->ksi_info);
1399 #ifndef _SYS_SYSPROTO_H_
1400 struct sigpending_args {
1405 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1407 struct proc *p = td->td_proc;
1411 pending = p->p_sigqueue.sq_signals;
1412 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1414 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1417 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1418 #ifndef _SYS_SYSPROTO_H_
1419 struct osigpending_args {
1424 osigpending(struct thread *td, struct osigpending_args *uap)
1426 struct proc *p = td->td_proc;
1430 pending = p->p_sigqueue.sq_signals;
1431 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1433 SIG2OSIG(pending, td->td_retval[0]);
1436 #endif /* COMPAT_43 */
1438 #if defined(COMPAT_43)
1440 * Generalized interface signal handler, 4.3-compatible.
1442 #ifndef _SYS_SYSPROTO_H_
1443 struct osigvec_args {
1451 osigvec(struct thread *td, struct osigvec_args *uap)
1454 struct sigaction nsa, osa;
1455 struct sigaction *nsap, *osap;
1458 if (uap->signum <= 0 || uap->signum >= ONSIG)
1460 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1461 osap = (uap->osv != NULL) ? &osa : NULL;
1463 error = copyin(uap->nsv, &vec, sizeof(vec));
1466 nsap->sa_handler = vec.sv_handler;
1467 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1468 nsap->sa_flags = vec.sv_flags;
1469 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1471 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1472 if (osap && !error) {
1473 vec.sv_handler = osap->sa_handler;
1474 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1475 vec.sv_flags = osap->sa_flags;
1476 vec.sv_flags &= ~SA_NOCLDWAIT;
1477 vec.sv_flags ^= SA_RESTART;
1478 error = copyout(&vec, uap->osv, sizeof(vec));
1483 #ifndef _SYS_SYSPROTO_H_
1484 struct osigblock_args {
1489 osigblock(struct thread *td, struct osigblock_args *uap)
1493 OSIG2SIG(uap->mask, set);
1494 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1495 SIG2OSIG(oset, td->td_retval[0]);
1499 #ifndef _SYS_SYSPROTO_H_
1500 struct osigsetmask_args {
1505 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1509 OSIG2SIG(uap->mask, set);
1510 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1511 SIG2OSIG(oset, td->td_retval[0]);
1514 #endif /* COMPAT_43 */
1517 * Suspend calling thread until signal, providing mask to be set in the
1520 #ifndef _SYS_SYSPROTO_H_
1521 struct sigsuspend_args {
1522 const sigset_t *sigmask;
1527 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1532 error = copyin(uap->sigmask, &mask, sizeof(mask));
1535 return (kern_sigsuspend(td, mask));
1539 kern_sigsuspend(struct thread *td, sigset_t mask)
1541 struct proc *p = td->td_proc;
1544 /* Ensure the sigfastblock value is up to date. */
1545 sigfastblock_fetch(td);
1548 * When returning from sigsuspend, we want
1549 * the old mask to be restored after the
1550 * signal handler has finished. Thus, we
1551 * save it here and mark the sigacts structure
1555 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1556 SIGPROCMASK_PROC_LOCKED);
1557 td->td_pflags |= TDP_OLDMASK;
1560 * Process signals now. Otherwise, we can get spurious wakeup
1561 * due to signal entered process queue, but delivered to other
1562 * thread. But sigsuspend should return only on signal
1565 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1566 for (has_sig = 0; !has_sig;) {
1567 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1570 thread_suspend_check(0);
1571 mtx_lock(&p->p_sigacts->ps_mtx);
1572 while ((sig = cursig(td)) != 0) {
1573 KASSERT(sig >= 0, ("sig %d", sig));
1574 has_sig += postsig(sig);
1576 mtx_unlock(&p->p_sigacts->ps_mtx);
1579 * If PTRACE_SCE or PTRACE_SCX were set after
1580 * userspace entered the syscall, return spurious
1583 if ((p->p_ptevents & PTRACE_SYSCALL) != 0)
1587 td->td_errno = EINTR;
1588 td->td_pflags |= TDP_NERRNO;
1589 return (EJUSTRETURN);
1592 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1594 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1595 * convention: libc stub passes mask, not pointer, to save a copyin.
1597 #ifndef _SYS_SYSPROTO_H_
1598 struct osigsuspend_args {
1604 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1608 OSIG2SIG(uap->mask, mask);
1609 return (kern_sigsuspend(td, mask));
1611 #endif /* COMPAT_43 */
1613 #if defined(COMPAT_43)
1614 #ifndef _SYS_SYSPROTO_H_
1615 struct osigstack_args {
1616 struct sigstack *nss;
1617 struct sigstack *oss;
1622 osigstack(struct thread *td, struct osigstack_args *uap)
1624 struct sigstack nss, oss;
1627 if (uap->nss != NULL) {
1628 error = copyin(uap->nss, &nss, sizeof(nss));
1632 oss.ss_sp = td->td_sigstk.ss_sp;
1633 oss.ss_onstack = sigonstack(cpu_getstack(td));
1634 if (uap->nss != NULL) {
1635 td->td_sigstk.ss_sp = nss.ss_sp;
1636 td->td_sigstk.ss_size = 0;
1637 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1638 td->td_pflags |= TDP_ALTSTACK;
1640 if (uap->oss != NULL)
1641 error = copyout(&oss, uap->oss, sizeof(oss));
1645 #endif /* COMPAT_43 */
1647 #ifndef _SYS_SYSPROTO_H_
1648 struct sigaltstack_args {
1655 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1660 if (uap->ss != NULL) {
1661 error = copyin(uap->ss, &ss, sizeof(ss));
1665 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1666 (uap->oss != NULL) ? &oss : NULL);
1669 if (uap->oss != NULL)
1670 error = copyout(&oss, uap->oss, sizeof(stack_t));
1675 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1677 struct proc *p = td->td_proc;
1680 oonstack = sigonstack(cpu_getstack(td));
1683 *oss = td->td_sigstk;
1684 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1685 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1691 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1693 if (!(ss->ss_flags & SS_DISABLE)) {
1694 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1697 td->td_sigstk = *ss;
1698 td->td_pflags |= TDP_ALTSTACK;
1700 td->td_pflags &= ~TDP_ALTSTACK;
1706 struct killpg1_ctx {
1716 killpg1_sendsig(struct proc *p, bool notself, struct killpg1_ctx *arg)
1720 if (p->p_pid <= 1 || (p->p_flag & P_SYSTEM) != 0 ||
1721 (notself && p == arg->td->td_proc) || p->p_state == PRS_NEW)
1724 err = p_cansignal(arg->td, p, arg->sig);
1725 if (err == 0 && arg->sig != 0)
1726 pksignal(p, arg->sig, arg->ksi);
1732 else if (arg->ret == 0 && err != ESRCH && err != EPERM)
1737 * Common code for kill process group/broadcast kill.
1738 * cp is calling process.
1741 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1745 struct killpg1_ctx arg;
1757 sx_slock(&allproc_lock);
1758 FOREACH_PROC_IN_SYSTEM(p) {
1759 killpg1_sendsig(p, true, &arg);
1761 sx_sunlock(&allproc_lock);
1763 sx_slock(&proctree_lock);
1766 * zero pgid means send to my process group.
1768 pgrp = td->td_proc->p_pgrp;
1771 pgrp = pgfind(pgid);
1773 sx_sunlock(&proctree_lock);
1777 sx_sunlock(&proctree_lock);
1778 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1779 killpg1_sendsig(p, false, &arg);
1783 MPASS(arg.ret != 0 || arg.found || !arg.sent);
1784 if (arg.ret == 0 && !arg.sent)
1785 arg.ret = arg.found ? EPERM : ESRCH;
1789 #ifndef _SYS_SYSPROTO_H_
1797 sys_kill(struct thread *td, struct kill_args *uap)
1800 return (kern_kill(td, uap->pid, uap->signum));
1804 kern_kill(struct thread *td, pid_t pid, int signum)
1811 * A process in capability mode can send signals only to himself.
1812 * The main rationale behind this is that abort(3) is implemented as
1813 * kill(getpid(), SIGABRT).
1815 if (IN_CAPABILITY_MODE(td) && pid != td->td_proc->p_pid)
1818 AUDIT_ARG_SIGNUM(signum);
1820 if ((u_int)signum > _SIG_MAXSIG)
1823 ksiginfo_init(&ksi);
1824 ksi.ksi_signo = signum;
1825 ksi.ksi_code = SI_USER;
1826 ksi.ksi_pid = td->td_proc->p_pid;
1827 ksi.ksi_uid = td->td_ucred->cr_ruid;
1830 /* kill single process */
1831 if ((p = pfind_any(pid)) == NULL)
1833 AUDIT_ARG_PROCESS(p);
1834 error = p_cansignal(td, p, signum);
1835 if (error == 0 && signum)
1836 pksignal(p, signum, &ksi);
1841 case -1: /* broadcast signal */
1842 return (killpg1(td, signum, 0, 1, &ksi));
1843 case 0: /* signal own process group */
1844 return (killpg1(td, signum, 0, 0, &ksi));
1845 default: /* negative explicit process group */
1846 return (killpg1(td, signum, -pid, 0, &ksi));
1852 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1857 AUDIT_ARG_SIGNUM(uap->signum);
1858 AUDIT_ARG_FD(uap->fd);
1859 if ((u_int)uap->signum > _SIG_MAXSIG)
1862 error = procdesc_find(td, uap->fd, &cap_pdkill_rights, &p);
1865 AUDIT_ARG_PROCESS(p);
1866 error = p_cansignal(td, p, uap->signum);
1867 if (error == 0 && uap->signum)
1868 kern_psignal(p, uap->signum);
1873 #if defined(COMPAT_43)
1874 #ifndef _SYS_SYSPROTO_H_
1875 struct okillpg_args {
1882 okillpg(struct thread *td, struct okillpg_args *uap)
1886 AUDIT_ARG_SIGNUM(uap->signum);
1887 AUDIT_ARG_PID(uap->pgid);
1888 if ((u_int)uap->signum > _SIG_MAXSIG)
1891 ksiginfo_init(&ksi);
1892 ksi.ksi_signo = uap->signum;
1893 ksi.ksi_code = SI_USER;
1894 ksi.ksi_pid = td->td_proc->p_pid;
1895 ksi.ksi_uid = td->td_ucred->cr_ruid;
1896 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1898 #endif /* COMPAT_43 */
1900 #ifndef _SYS_SYSPROTO_H_
1901 struct sigqueue_args {
1904 /* union sigval */ void *value;
1908 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1912 sv.sival_ptr = uap->value;
1914 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1918 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1924 if ((u_int)signum > _SIG_MAXSIG)
1928 * Specification says sigqueue can only send signal to
1934 if ((p = pfind_any(pid)) == NULL)
1936 error = p_cansignal(td, p, signum);
1937 if (error == 0 && signum != 0) {
1938 ksiginfo_init(&ksi);
1939 ksi.ksi_flags = KSI_SIGQ;
1940 ksi.ksi_signo = signum;
1941 ksi.ksi_code = SI_QUEUE;
1942 ksi.ksi_pid = td->td_proc->p_pid;
1943 ksi.ksi_uid = td->td_ucred->cr_ruid;
1944 ksi.ksi_value = *value;
1945 error = pksignal(p, ksi.ksi_signo, &ksi);
1952 * Send a signal to a process group.
1955 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1960 sx_slock(&proctree_lock);
1961 pgrp = pgfind(pgid);
1962 sx_sunlock(&proctree_lock);
1964 pgsignal(pgrp, sig, 0, ksi);
1971 * Send a signal to a process group. If checktty is 1,
1972 * limit to members which have a controlling terminal.
1975 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1980 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1981 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1983 if (p->p_state == PRS_NORMAL &&
1984 (checkctty == 0 || p->p_flag & P_CONTROLT))
1985 pksignal(p, sig, ksi);
1992 * Recalculate the signal mask and reset the signal disposition after
1993 * usermode frame for delivery is formed. Should be called after
1994 * mach-specific routine, because sysent->sv_sendsig() needs correct
1995 * ps_siginfo and signal mask.
1998 postsig_done(int sig, struct thread *td, struct sigacts *ps)
2002 mtx_assert(&ps->ps_mtx, MA_OWNED);
2003 td->td_ru.ru_nsignals++;
2004 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2005 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2006 SIGADDSET(mask, sig);
2007 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2008 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2009 if (SIGISMEMBER(ps->ps_sigreset, sig))
2014 * Send a signal caused by a trap to the current thread. If it will be
2015 * caught immediately, deliver it with correct code. Otherwise, post it
2019 trapsignal(struct thread *td, ksiginfo_t *ksi)
2027 sig = ksi->ksi_signo;
2028 code = ksi->ksi_code;
2029 KASSERT(_SIG_VALID(sig), ("invalid signal"));
2031 sigfastblock_fetch(td);
2034 mtx_lock(&ps->ps_mtx);
2035 sigmask = td->td_sigmask;
2036 if (td->td_sigblock_val != 0)
2037 SIGSETOR(sigmask, fastblock_mask);
2038 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
2039 !SIGISMEMBER(sigmask, sig)) {
2041 if (KTRPOINT(curthread, KTR_PSIG))
2042 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
2043 &td->td_sigmask, code);
2045 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
2046 ksi, &td->td_sigmask);
2047 postsig_done(sig, td, ps);
2048 mtx_unlock(&ps->ps_mtx);
2051 * Avoid a possible infinite loop if the thread
2052 * masking the signal or process is ignoring the
2055 if (kern_forcesigexit && (SIGISMEMBER(sigmask, sig) ||
2056 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
2057 SIGDELSET(td->td_sigmask, sig);
2058 SIGDELSET(ps->ps_sigcatch, sig);
2059 SIGDELSET(ps->ps_sigignore, sig);
2060 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2061 td->td_pflags &= ~TDP_SIGFASTBLOCK;
2062 td->td_sigblock_val = 0;
2064 mtx_unlock(&ps->ps_mtx);
2065 p->p_sig = sig; /* XXX to verify code */
2066 tdsendsignal(p, td, sig, ksi);
2071 static struct thread *
2072 sigtd(struct proc *p, int sig, bool fast_sigblock)
2074 struct thread *td, *signal_td;
2076 PROC_LOCK_ASSERT(p, MA_OWNED);
2077 MPASS(!fast_sigblock || p == curproc);
2080 * Check if current thread can handle the signal without
2081 * switching context to another thread.
2083 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig) &&
2084 (!fast_sigblock || curthread->td_sigblock_val == 0))
2087 FOREACH_THREAD_IN_PROC(p, td) {
2088 if (!SIGISMEMBER(td->td_sigmask, sig) && (!fast_sigblock ||
2089 td != curthread || td->td_sigblock_val == 0)) {
2094 if (signal_td == NULL)
2095 signal_td = FIRST_THREAD_IN_PROC(p);
2100 * Send the signal to the process. If the signal has an action, the action
2101 * is usually performed by the target process rather than the caller; we add
2102 * the signal to the set of pending signals for the process.
2105 * o When a stop signal is sent to a sleeping process that takes the
2106 * default action, the process is stopped without awakening it.
2107 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2108 * regardless of the signal action (eg, blocked or ignored).
2110 * Other ignored signals are discarded immediately.
2112 * NB: This function may be entered from the debugger via the "kill" DDB
2113 * command. There is little that can be done to mitigate the possibly messy
2114 * side effects of this unwise possibility.
2117 kern_psignal(struct proc *p, int sig)
2121 ksiginfo_init(&ksi);
2122 ksi.ksi_signo = sig;
2123 ksi.ksi_code = SI_KERNEL;
2124 (void) tdsendsignal(p, NULL, sig, &ksi);
2128 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2131 return (tdsendsignal(p, NULL, sig, ksi));
2134 /* Utility function for finding a thread to send signal event to. */
2136 sigev_findtd(struct proc *p, struct sigevent *sigev, struct thread **ttd)
2140 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2141 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2153 tdsignal(struct thread *td, int sig)
2157 ksiginfo_init(&ksi);
2158 ksi.ksi_signo = sig;
2159 ksi.ksi_code = SI_KERNEL;
2160 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2164 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2167 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2171 sig_sleepq_abort(struct thread *td, int intrval)
2173 THREAD_LOCK_ASSERT(td, MA_OWNED);
2175 if (intrval == 0 && (td->td_flags & TDF_SIGWAIT) == 0) {
2179 return (sleepq_abort(td, intrval));
2183 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2186 sigqueue_t *sigqueue;
2193 MPASS(td == NULL || p == td->td_proc);
2194 PROC_LOCK_ASSERT(p, MA_OWNED);
2196 if (!_SIG_VALID(sig))
2197 panic("%s(): invalid signal %d", __func__, sig);
2199 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2202 * IEEE Std 1003.1-2001: return success when killing a zombie.
2204 if (p->p_state == PRS_ZOMBIE) {
2205 if (ksi && (ksi->ksi_flags & KSI_INS))
2206 ksiginfo_tryfree(ksi);
2211 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2212 prop = sigprop(sig);
2215 td = sigtd(p, sig, false);
2216 sigqueue = &p->p_sigqueue;
2218 sigqueue = &td->td_sigqueue;
2220 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2223 * If the signal is being ignored, then we forget about it
2224 * immediately, except when the target process executes
2225 * sigwait(). (Note: we don't set SIGCONT in ps_sigignore,
2226 * and if it is set to SIG_IGN, action will be SIG_DFL here.)
2228 mtx_lock(&ps->ps_mtx);
2229 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2230 if (kern_sig_discard_ign &&
2231 (p->p_sysent->sv_flags & SV_SIG_DISCIGN) == 0) {
2232 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2234 mtx_unlock(&ps->ps_mtx);
2235 if (ksi && (ksi->ksi_flags & KSI_INS))
2236 ksiginfo_tryfree(ksi);
2243 if (SIGISMEMBER(td->td_sigmask, sig))
2245 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2249 if (SIGISMEMBER(ps->ps_sigintr, sig))
2254 mtx_unlock(&ps->ps_mtx);
2256 if (prop & SIGPROP_CONT)
2257 sigqueue_delete_stopmask_proc(p);
2258 else if (prop & SIGPROP_STOP) {
2260 * If sending a tty stop signal to a member of an orphaned
2261 * process group, discard the signal here if the action
2262 * is default; don't stop the process below if sleeping,
2263 * and don't clear any pending SIGCONT.
2265 if ((prop & SIGPROP_TTYSTOP) != 0 &&
2266 (p->p_pgrp->pg_flags & PGRP_ORPHANED) != 0 &&
2267 action == SIG_DFL) {
2268 if (ksi && (ksi->ksi_flags & KSI_INS))
2269 ksiginfo_tryfree(ksi);
2272 sigqueue_delete_proc(p, SIGCONT);
2273 if (p->p_flag & P_CONTINUED) {
2274 p->p_flag &= ~P_CONTINUED;
2275 PROC_LOCK(p->p_pptr);
2276 sigqueue_take(p->p_ksi);
2277 PROC_UNLOCK(p->p_pptr);
2281 ret = sigqueue_add(sigqueue, sig, ksi);
2286 * Defer further processing for signals which are held,
2287 * except that stopped processes must be continued by SIGCONT.
2289 if (action == SIG_HOLD &&
2290 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2296 * Some signals have a process-wide effect and a per-thread
2297 * component. Most processing occurs when the process next
2298 * tries to cross the user boundary, however there are some
2299 * times when processing needs to be done immediately, such as
2300 * waking up threads so that they can cross the user boundary.
2301 * We try to do the per-process part here.
2303 if (P_SHOULDSTOP(p)) {
2304 KASSERT(!(p->p_flag & P_WEXIT),
2305 ("signal to stopped but exiting process"));
2306 if (sig == SIGKILL) {
2308 * If traced process is already stopped,
2309 * then no further action is necessary.
2311 if (p->p_flag & P_TRACED)
2314 * SIGKILL sets process running.
2315 * It will die elsewhere.
2316 * All threads must be restarted.
2318 p->p_flag &= ~P_STOPPED_SIG;
2322 if (prop & SIGPROP_CONT) {
2324 * If traced process is already stopped,
2325 * then no further action is necessary.
2327 if (p->p_flag & P_TRACED)
2330 * If SIGCONT is default (or ignored), we continue the
2331 * process but don't leave the signal in sigqueue as
2332 * it has no further action. If SIGCONT is held, we
2333 * continue the process and leave the signal in
2334 * sigqueue. If the process catches SIGCONT, let it
2335 * handle the signal itself. If it isn't waiting on
2336 * an event, it goes back to run state.
2337 * Otherwise, process goes back to sleep state.
2339 p->p_flag &= ~P_STOPPED_SIG;
2341 if (p->p_numthreads == p->p_suspcount) {
2343 p->p_flag |= P_CONTINUED;
2344 p->p_xsig = SIGCONT;
2345 PROC_LOCK(p->p_pptr);
2346 childproc_continued(p);
2347 PROC_UNLOCK(p->p_pptr);
2350 if (action == SIG_DFL) {
2351 thread_unsuspend(p);
2353 sigqueue_delete(sigqueue, sig);
2356 if (action == SIG_CATCH) {
2358 * The process wants to catch it so it needs
2359 * to run at least one thread, but which one?
2365 * The signal is not ignored or caught.
2367 thread_unsuspend(p);
2372 if (prop & SIGPROP_STOP) {
2374 * If traced process is already stopped,
2375 * then no further action is necessary.
2377 if (p->p_flag & P_TRACED)
2380 * Already stopped, don't need to stop again
2381 * (If we did the shell could get confused).
2382 * Just make sure the signal STOP bit set.
2384 p->p_flag |= P_STOPPED_SIG;
2385 sigqueue_delete(sigqueue, sig);
2390 * All other kinds of signals:
2391 * If a thread is sleeping interruptibly, simulate a
2392 * wakeup so that when it is continued it will be made
2393 * runnable and can look at the signal. However, don't make
2394 * the PROCESS runnable, leave it stopped.
2395 * It may run a bit until it hits a thread_suspend_check().
2399 if (TD_CAN_ABORT(td))
2400 wakeup_swapper = sig_sleepq_abort(td, intrval);
2406 * Mutexes are short lived. Threads waiting on them will
2407 * hit thread_suspend_check() soon.
2409 } else if (p->p_state == PRS_NORMAL) {
2410 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2411 tdsigwakeup(td, sig, action, intrval);
2415 MPASS(action == SIG_DFL);
2417 if (prop & SIGPROP_STOP) {
2418 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2420 p->p_flag |= P_STOPPED_SIG;
2423 wakeup_swapper = sig_suspend_threads(td, p, 1);
2424 if (p->p_numthreads == p->p_suspcount) {
2426 * only thread sending signal to another
2427 * process can reach here, if thread is sending
2428 * signal to its process, because thread does
2429 * not suspend itself here, p_numthreads
2430 * should never be equal to p_suspcount.
2434 sigqueue_delete_proc(p, p->p_xsig);
2440 /* Not in "NORMAL" state. discard the signal. */
2441 sigqueue_delete(sigqueue, sig);
2446 * The process is not stopped so we need to apply the signal to all the
2450 tdsigwakeup(td, sig, action, intrval);
2452 thread_unsuspend(p);
2455 itimer_proc_continue(p);
2456 kqtimer_proc_continue(p);
2458 /* If we jump here, proc slock should not be owned. */
2459 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2467 * The force of a signal has been directed against a single
2468 * thread. We need to see what we can do about knocking it
2469 * out of any sleep it may be in etc.
2472 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2474 struct proc *p = td->td_proc;
2475 int prop, wakeup_swapper;
2477 PROC_LOCK_ASSERT(p, MA_OWNED);
2478 prop = sigprop(sig);
2483 * Bring the priority of a thread up if we want it to get
2484 * killed in this lifetime. Be careful to avoid bumping the
2485 * priority of the idle thread, since we still allow to signal
2488 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2489 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2490 sched_prio(td, PUSER);
2491 if (TD_ON_SLEEPQ(td)) {
2493 * If thread is sleeping uninterruptibly
2494 * we can't interrupt the sleep... the signal will
2495 * be noticed when the process returns through
2496 * trap() or syscall().
2498 if ((td->td_flags & TDF_SINTR) == 0)
2501 * If SIGCONT is default (or ignored) and process is
2502 * asleep, we are finished; the process should not
2505 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2508 sigqueue_delete(&p->p_sigqueue, sig);
2510 * It may be on either list in this state.
2511 * Remove from both for now.
2513 sigqueue_delete(&td->td_sigqueue, sig);
2518 * Don't awaken a sleeping thread for SIGSTOP if the
2519 * STOP signal is deferred.
2521 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2522 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2526 * Give low priority threads a better chance to run.
2528 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2529 sched_prio(td, PUSER);
2531 wakeup_swapper = sig_sleepq_abort(td, intrval);
2539 * Other states do nothing with the signal immediately,
2540 * other than kicking ourselves if we are running.
2541 * It will either never be noticed, or noticed very soon.
2544 if (TD_IS_RUNNING(td) && td != curthread)
2554 ptrace_coredump(struct thread *td)
2557 struct thr_coredump_req *tcq;
2560 MPASS(td == curthread);
2562 PROC_LOCK_ASSERT(p, MA_OWNED);
2563 if ((td->td_dbgflags & TDB_COREDUMPRQ) == 0)
2565 KASSERT((p->p_flag & P_STOPPED_TRACE) != 0, ("not stopped"));
2567 tcq = td->td_coredump;
2568 KASSERT(tcq != NULL, ("td_coredump is NULL"));
2570 if (p->p_sysent->sv_coredump == NULL) {
2571 tcq->tc_error = ENOSYS;
2576 rl_cookie = vn_rangelock_wlock(tcq->tc_vp, 0, OFF_MAX);
2578 tcq->tc_error = p->p_sysent->sv_coredump(td, tcq->tc_vp,
2579 tcq->tc_limit, tcq->tc_flags);
2581 vn_rangelock_unlock(tcq->tc_vp, rl_cookie);
2584 td->td_dbgflags &= ~TDB_COREDUMPRQ;
2585 td->td_coredump = NULL;
2590 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2595 PROC_LOCK_ASSERT(p, MA_OWNED);
2596 PROC_SLOCK_ASSERT(p, MA_OWNED);
2597 MPASS(sending || td == curthread);
2600 FOREACH_THREAD_IN_PROC(p, td2) {
2602 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2603 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2604 (td2->td_flags & TDF_SINTR)) {
2605 if (td2->td_flags & TDF_SBDRY) {
2607 * Once a thread is asleep with
2608 * TDF_SBDRY and without TDF_SERESTART
2609 * or TDF_SEINTR set, it should never
2610 * become suspended due to this check.
2612 KASSERT(!TD_IS_SUSPENDED(td2),
2613 ("thread with deferred stops suspended"));
2614 if (TD_SBDRY_INTR(td2)) {
2615 wakeup_swapper |= sleepq_abort(td2,
2616 TD_SBDRY_ERRNO(td2));
2619 } else if (!TD_IS_SUSPENDED(td2))
2620 thread_suspend_one(td2);
2621 } else if (!TD_IS_SUSPENDED(td2)) {
2622 if (sending || td != td2)
2623 td2->td_flags |= TDF_ASTPENDING;
2625 if (TD_IS_RUNNING(td2) && td2 != td)
2626 forward_signal(td2);
2631 return (wakeup_swapper);
2635 * Stop the process for an event deemed interesting to the debugger. If si is
2636 * non-NULL, this is a signal exchange; the new signal requested by the
2637 * debugger will be returned for handling. If si is NULL, this is some other
2638 * type of interesting event. The debugger may request a signal be delivered in
2639 * that case as well, however it will be deferred until it can be handled.
2642 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2644 struct proc *p = td->td_proc;
2648 PROC_LOCK_ASSERT(p, MA_OWNED);
2649 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2650 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2651 &p->p_mtx.lock_object, "Stopping for traced signal");
2655 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2656 td->td_dbgflags |= TDB_XSIG;
2657 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2658 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2660 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2663 * Ensure that, if we've been PT_KILLed, the
2664 * exit status reflects that. Another thread
2665 * may also be in ptracestop(), having just
2666 * received the SIGKILL, but this thread was
2667 * unsuspended first.
2669 td->td_dbgflags &= ~TDB_XSIG;
2670 td->td_xsig = SIGKILL;
2674 if (p->p_flag & P_SINGLE_EXIT &&
2675 !(td->td_dbgflags & TDB_EXIT)) {
2677 * Ignore ptrace stops except for thread exit
2678 * events when the process exits.
2680 td->td_dbgflags &= ~TDB_XSIG;
2686 * Make wait(2) work. Ensure that right after the
2687 * attach, the thread which was decided to become the
2688 * leader of attach gets reported to the waiter.
2689 * Otherwise, just avoid overwriting another thread's
2690 * assignment to p_xthread. If another thread has
2691 * already set p_xthread, the current thread will get
2692 * a chance to report itself upon the next iteration.
2694 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2695 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2696 p->p_xthread == NULL)) {
2701 * If we are on sleepqueue already,
2702 * let sleepqueue code decide if it
2703 * needs to go sleep after attach.
2705 if (td->td_wchan == NULL)
2706 td->td_dbgflags &= ~TDB_FSTP;
2708 p->p_flag2 &= ~P2_PTRACE_FSTP;
2709 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2710 sig_suspend_threads(td, p, 0);
2712 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2713 td->td_dbgflags &= ~TDB_STOPATFORK;
2716 td->td_dbgflags |= TDB_SSWITCH;
2717 thread_suspend_switch(td, p);
2718 td->td_dbgflags &= ~TDB_SSWITCH;
2719 if ((td->td_dbgflags & TDB_COREDUMPRQ) != 0) {
2721 ptrace_coredump(td);
2725 if (p->p_xthread == td)
2726 p->p_xthread = NULL;
2727 if (!(p->p_flag & P_TRACED))
2729 if (td->td_dbgflags & TDB_SUSPEND) {
2730 if (p->p_flag & P_SINGLE_EXIT)
2738 if (si != NULL && sig == td->td_xsig) {
2739 /* Parent wants us to take the original signal unchanged. */
2740 si->ksi_flags |= KSI_HEAD;
2741 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2743 } else if (td->td_xsig != 0) {
2745 * If parent wants us to take a new signal, then it will leave
2746 * it in td->td_xsig; otherwise we just look for signals again.
2748 ksiginfo_init(&ksi);
2749 ksi.ksi_signo = td->td_xsig;
2750 ksi.ksi_flags |= KSI_PTRACE;
2751 td2 = sigtd(p, td->td_xsig, false);
2752 tdsendsignal(p, td2, td->td_xsig, &ksi);
2757 return (td->td_xsig);
2761 reschedule_signals(struct proc *p, sigset_t block, int flags)
2766 bool fastblk, pslocked;
2768 PROC_LOCK_ASSERT(p, MA_OWNED);
2770 pslocked = (flags & SIGPROCMASK_PS_LOCKED) != 0;
2771 mtx_assert(&ps->ps_mtx, pslocked ? MA_OWNED : MA_NOTOWNED);
2772 if (SIGISEMPTY(p->p_siglist))
2774 SIGSETAND(block, p->p_siglist);
2775 fastblk = (flags & SIGPROCMASK_FASTBLK) != 0;
2776 SIG_FOREACH(sig, &block) {
2777 td = sigtd(p, sig, fastblk);
2780 * If sigtd() selected us despite sigfastblock is
2781 * blocking, do not activate AST or wake us, to avoid
2782 * loop in AST handler.
2784 if (fastblk && td == curthread)
2789 mtx_lock(&ps->ps_mtx);
2790 if (p->p_flag & P_TRACED ||
2791 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2792 !SIGISMEMBER(td->td_sigmask, sig))) {
2793 tdsigwakeup(td, sig, SIG_CATCH,
2794 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2798 mtx_unlock(&ps->ps_mtx);
2803 tdsigcleanup(struct thread *td)
2809 PROC_LOCK_ASSERT(p, MA_OWNED);
2811 sigqueue_flush(&td->td_sigqueue);
2812 if (p->p_numthreads == 1)
2816 * Since we cannot handle signals, notify signal post code
2817 * about this by filling the sigmask.
2819 * Also, if needed, wake up thread(s) that do not block the
2820 * same signals as the exiting thread, since the thread might
2821 * have been selected for delivery and woken up.
2823 SIGFILLSET(unblocked);
2824 SIGSETNAND(unblocked, td->td_sigmask);
2825 SIGFILLSET(td->td_sigmask);
2826 reschedule_signals(p, unblocked, 0);
2831 sigdeferstop_curr_flags(int cflags)
2834 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2835 (cflags & TDF_SBDRY) != 0);
2836 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2840 * Defer the delivery of SIGSTOP for the current thread, according to
2841 * the requested mode. Returns previous flags, which must be restored
2842 * by sigallowstop().
2844 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2845 * cleared by the current thread, which allow the lock-less read-only
2849 sigdeferstop_impl(int mode)
2855 cflags = sigdeferstop_curr_flags(td->td_flags);
2857 case SIGDEFERSTOP_NOP:
2860 case SIGDEFERSTOP_OFF:
2863 case SIGDEFERSTOP_SILENT:
2864 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2866 case SIGDEFERSTOP_EINTR:
2867 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2869 case SIGDEFERSTOP_ERESTART:
2870 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2873 panic("sigdeferstop: invalid mode %x", mode);
2876 if (cflags == nflags)
2877 return (SIGDEFERSTOP_VAL_NCHG);
2879 td->td_flags = (td->td_flags & ~cflags) | nflags;
2885 * Restores the STOP handling mode, typically permitting the delivery
2886 * of SIGSTOP for the current thread. This does not immediately
2887 * suspend if a stop was posted. Instead, the thread will suspend
2888 * either via ast() or a subsequent interruptible sleep.
2891 sigallowstop_impl(int prev)
2896 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2897 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2898 ("sigallowstop: incorrect previous mode %x", prev));
2900 cflags = sigdeferstop_curr_flags(td->td_flags);
2901 if (cflags != prev) {
2903 td->td_flags = (td->td_flags & ~cflags) | prev;
2912 SIGSTATUS_SBDRY_STOP,
2916 * The thread has signal "sig" pending. Figure out what to do with it:
2918 * _HANDLE -> the caller should handle the signal
2919 * _HANDLED -> handled internally, reload pending signal set
2920 * _IGNORE -> ignored, remove from the set of pending signals and try the
2921 * next pending signal
2922 * _SBDRY_STOP -> the signal should stop the thread but this is not
2923 * permitted in the current context
2925 static enum sigstatus
2926 sigprocess(struct thread *td, int sig)
2930 struct sigqueue *queue;
2934 KASSERT(_SIG_VALID(sig), ("%s: invalid signal %d", __func__, sig));
2938 mtx_assert(&ps->ps_mtx, MA_OWNED);
2939 PROC_LOCK_ASSERT(p, MA_OWNED);
2942 * We should allow pending but ignored signals below
2943 * only if there is sigwait() active, or P_TRACED was
2944 * on when they were posted.
2946 if (SIGISMEMBER(ps->ps_sigignore, sig) &&
2947 (p->p_flag & P_TRACED) == 0 &&
2948 (td->td_flags & TDF_SIGWAIT) == 0) {
2949 return (SIGSTATUS_IGNORE);
2952 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2954 * If traced, always stop.
2955 * Remove old signal from queue before the stop.
2956 * XXX shrug off debugger, it causes siginfo to
2959 queue = &td->td_sigqueue;
2960 ksiginfo_init(&ksi);
2961 if (sigqueue_get(queue, sig, &ksi) == 0) {
2962 queue = &p->p_sigqueue;
2963 sigqueue_get(queue, sig, &ksi);
2965 td->td_si = ksi.ksi_info;
2967 mtx_unlock(&ps->ps_mtx);
2968 sig = ptracestop(td, sig, &ksi);
2969 mtx_lock(&ps->ps_mtx);
2971 td->td_si.si_signo = 0;
2974 * Keep looking if the debugger discarded or
2975 * replaced the signal.
2978 return (SIGSTATUS_HANDLED);
2981 * If the signal became masked, re-queue it.
2983 if (SIGISMEMBER(td->td_sigmask, sig)) {
2984 ksi.ksi_flags |= KSI_HEAD;
2985 sigqueue_add(&p->p_sigqueue, sig, &ksi);
2986 return (SIGSTATUS_HANDLED);
2990 * If the traced bit got turned off, requeue the signal and
2991 * reload the set of pending signals. This ensures that p_sig*
2992 * and p_sigact are consistent.
2994 if ((p->p_flag & P_TRACED) == 0) {
2995 ksi.ksi_flags |= KSI_HEAD;
2996 sigqueue_add(queue, sig, &ksi);
2997 return (SIGSTATUS_HANDLED);
3002 * Decide whether the signal should be returned.
3003 * Return the signal's number, or fall through
3004 * to clear it from the pending mask.
3006 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
3007 case (intptr_t)SIG_DFL:
3009 * Don't take default actions on system processes.
3011 if (p->p_pid <= 1) {
3014 * Are you sure you want to ignore SIGSEGV
3017 printf("Process (pid %lu) got signal %d\n",
3018 (u_long)p->p_pid, sig);
3020 return (SIGSTATUS_IGNORE);
3024 * If there is a pending stop signal to process with
3025 * default action, stop here, then clear the signal.
3026 * Traced or exiting processes should ignore stops.
3027 * Additionally, a member of an orphaned process group
3028 * should ignore tty stops.
3030 prop = sigprop(sig);
3031 if (prop & SIGPROP_STOP) {
3032 mtx_unlock(&ps->ps_mtx);
3033 if ((p->p_flag & (P_TRACED | P_WEXIT |
3034 P_SINGLE_EXIT)) != 0 || ((p->p_pgrp->
3035 pg_flags & PGRP_ORPHANED) != 0 &&
3036 (prop & SIGPROP_TTYSTOP) != 0)) {
3037 mtx_lock(&ps->ps_mtx);
3038 return (SIGSTATUS_IGNORE);
3040 if (TD_SBDRY_INTR(td)) {
3041 KASSERT((td->td_flags & TDF_SBDRY) != 0,
3042 ("lost TDF_SBDRY"));
3043 mtx_lock(&ps->ps_mtx);
3044 return (SIGSTATUS_SBDRY_STOP);
3046 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
3047 &p->p_mtx.lock_object, "Catching SIGSTOP");
3048 sigqueue_delete(&td->td_sigqueue, sig);
3049 sigqueue_delete(&p->p_sigqueue, sig);
3050 p->p_flag |= P_STOPPED_SIG;
3053 sig_suspend_threads(td, p, 0);
3054 thread_suspend_switch(td, p);
3056 mtx_lock(&ps->ps_mtx);
3057 return (SIGSTATUS_HANDLED);
3058 } else if ((prop & SIGPROP_IGNORE) != 0 &&
3059 (td->td_flags & TDF_SIGWAIT) == 0) {
3061 * Default action is to ignore; drop it if
3062 * not in kern_sigtimedwait().
3064 return (SIGSTATUS_IGNORE);
3066 return (SIGSTATUS_HANDLE);
3069 case (intptr_t)SIG_IGN:
3070 if ((td->td_flags & TDF_SIGWAIT) == 0)
3071 return (SIGSTATUS_IGNORE);
3073 return (SIGSTATUS_HANDLE);
3077 * This signal has an action, let postsig() process it.
3079 return (SIGSTATUS_HANDLE);
3084 * If the current process has received a signal (should be caught or cause
3085 * termination, should interrupt current syscall), return the signal number.
3086 * Stop signals with default action are processed immediately, then cleared;
3087 * they aren't returned. This is checked after each entry to the system for
3088 * a syscall or trap (though this can usually be done without calling
3089 * issignal by checking the pending signal masks in cursig.) The normal call
3092 * while (sig = cursig(curthread))
3096 issignal(struct thread *td)
3099 sigset_t sigpending;
3103 PROC_LOCK_ASSERT(p, MA_OWNED);
3106 sigpending = td->td_sigqueue.sq_signals;
3107 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
3108 SIGSETNAND(sigpending, td->td_sigmask);
3110 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
3111 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
3112 SIG_STOPSIGMASK(sigpending);
3113 if (SIGISEMPTY(sigpending)) /* no signal to send */
3117 * Do fast sigblock if requested by usermode. Since
3118 * we do know that there was a signal pending at this
3119 * point, set the FAST_SIGBLOCK_PEND as indicator for
3120 * usermode to perform a dummy call to
3121 * FAST_SIGBLOCK_UNBLOCK, which causes immediate
3122 * delivery of postponed pending signal.
3124 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
3125 if (td->td_sigblock_val != 0)
3126 SIGSETNAND(sigpending, fastblock_mask);
3127 if (SIGISEMPTY(sigpending)) {
3128 td->td_pflags |= TDP_SIGFASTPENDING;
3133 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
3134 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
3135 SIGISMEMBER(sigpending, SIGSTOP)) {
3137 * If debugger just attached, always consume
3138 * SIGSTOP from ptrace(PT_ATTACH) first, to
3139 * execute the debugger attach ritual in
3142 td->td_dbgflags |= TDB_FSTP;
3143 SIGEMPTYSET(sigpending);
3144 SIGADDSET(sigpending, SIGSTOP);
3147 SIG_FOREACH(sig, &sigpending) {
3148 switch (sigprocess(td, sig)) {
3149 case SIGSTATUS_HANDLE:
3151 case SIGSTATUS_HANDLED:
3153 case SIGSTATUS_IGNORE:
3154 sigqueue_delete(&td->td_sigqueue, sig);
3155 sigqueue_delete(&p->p_sigqueue, sig);
3157 case SIGSTATUS_SBDRY_STOP:
3166 thread_stopped(struct proc *p)
3170 PROC_LOCK_ASSERT(p, MA_OWNED);
3171 PROC_SLOCK_ASSERT(p, MA_OWNED);
3175 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
3177 p->p_flag &= ~P_WAITED;
3178 PROC_LOCK(p->p_pptr);
3179 childproc_stopped(p, (p->p_flag & P_TRACED) ?
3180 CLD_TRAPPED : CLD_STOPPED);
3181 PROC_UNLOCK(p->p_pptr);
3187 * Take the action for the specified signal
3188 * from the current set of pending signals.
3198 sigset_t returnmask;
3200 KASSERT(sig != 0, ("postsig"));
3204 PROC_LOCK_ASSERT(p, MA_OWNED);
3206 mtx_assert(&ps->ps_mtx, MA_OWNED);
3207 ksiginfo_init(&ksi);
3208 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3209 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3211 ksi.ksi_signo = sig;
3212 if (ksi.ksi_code == SI_TIMER)
3213 itimer_accept(p, ksi.ksi_timerid, &ksi);
3214 action = ps->ps_sigact[_SIG_IDX(sig)];
3216 if (KTRPOINT(td, KTR_PSIG))
3217 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3218 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3221 if (action == SIG_DFL) {
3223 * Default action, where the default is to kill
3224 * the process. (Other cases were ignored above.)
3226 mtx_unlock(&ps->ps_mtx);
3227 proc_td_siginfo_capture(td, &ksi.ksi_info);
3232 * If we get here, the signal must be caught.
3234 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3235 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3236 ("postsig action: blocked sig %d", sig));
3239 * Set the new mask value and also defer further
3240 * occurrences of this signal.
3242 * Special case: user has done a sigsuspend. Here the
3243 * current mask is not of interest, but rather the
3244 * mask from before the sigsuspend is what we want
3245 * restored after the signal processing is completed.
3247 if (td->td_pflags & TDP_OLDMASK) {
3248 returnmask = td->td_oldsigmask;
3249 td->td_pflags &= ~TDP_OLDMASK;
3251 returnmask = td->td_sigmask;
3253 if (p->p_sig == sig) {
3256 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3257 postsig_done(sig, td, ps);
3263 sig_ast_checksusp(struct thread *td)
3265 struct proc *p __diagused;
3269 PROC_LOCK_ASSERT(p, MA_OWNED);
3271 if ((td->td_flags & TDF_NEEDSUSPCHK) == 0)
3274 ret = thread_suspend_check(1);
3275 MPASS(ret == 0 || ret == EINTR || ret == ERESTART);
3280 sig_ast_needsigchk(struct thread *td)
3287 PROC_LOCK_ASSERT(p, MA_OWNED);
3289 if ((td->td_flags & TDF_NEEDSIGCHK) == 0)
3293 mtx_lock(&ps->ps_mtx);
3296 mtx_unlock(&ps->ps_mtx);
3297 KASSERT((td->td_flags & TDF_SBDRY) != 0, ("lost TDF_SBDRY"));
3298 KASSERT(TD_SBDRY_INTR(td),
3299 ("lost TDF_SERESTART of TDF_SEINTR"));
3300 KASSERT((td->td_flags & (TDF_SEINTR | TDF_SERESTART)) !=
3301 (TDF_SEINTR | TDF_SERESTART),
3302 ("both TDF_SEINTR and TDF_SERESTART"));
3303 ret = TD_SBDRY_ERRNO(td);
3304 } else if (sig != 0) {
3305 ret = SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR : ERESTART;
3306 mtx_unlock(&ps->ps_mtx);
3308 mtx_unlock(&ps->ps_mtx);
3313 * Do not go into sleep if this thread was the ptrace(2)
3314 * attach leader. cursig() consumed SIGSTOP from PT_ATTACH,
3315 * but we usually act on the signal by interrupting sleep, and
3316 * should do that here as well.
3318 if ((td->td_dbgflags & TDB_FSTP) != 0) {
3321 td->td_dbgflags &= ~TDB_FSTP;
3335 if ((td->td_flags & (TDF_NEEDSIGCHK | TDF_NEEDSUSPCHK)) == 0)
3341 ret = sig_ast_checksusp(td);
3343 ret = sig_ast_needsigchk(td);
3349 curproc_sigkilled(void)
3357 if ((td->td_flags & TDF_NEEDSIGCHK) == 0)
3363 mtx_lock(&ps->ps_mtx);
3364 res = SIGISMEMBER(td->td_sigqueue.sq_signals, SIGKILL) ||
3365 SIGISMEMBER(p->p_sigqueue.sq_signals, SIGKILL);
3366 mtx_unlock(&ps->ps_mtx);
3372 proc_wkilled(struct proc *p)
3375 PROC_LOCK_ASSERT(p, MA_OWNED);
3376 if ((p->p_flag & P_WKILLED) == 0) {
3377 p->p_flag |= P_WKILLED;
3379 * Notify swapper that there is a process to swap in.
3380 * The notification is racy, at worst it would take 10
3381 * seconds for the swapper process to notice.
3383 if ((p->p_flag & (P_INMEM | P_SWAPPINGIN)) == 0)
3389 * Kill the current process for stated reason.
3392 killproc(struct proc *p, const char *why)
3395 PROC_LOCK_ASSERT(p, MA_OWNED);
3396 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3398 log(LOG_ERR, "pid %d (%s), jid %d, uid %d, was killed: %s\n",
3399 p->p_pid, p->p_comm, p->p_ucred->cr_prison->pr_id,
3400 p->p_ucred->cr_uid, why);
3402 kern_psignal(p, SIGKILL);
3406 * Force the current process to exit with the specified signal, dumping core
3407 * if appropriate. We bypass the normal tests for masked and caught signals,
3408 * allowing unrecoverable failures to terminate the process without changing
3409 * signal state. Mark the accounting record with the signal termination.
3410 * If dumping core, save the signal number for the debugger. Calls exit and
3414 sigexit(struct thread *td, int sig)
3416 struct proc *p = td->td_proc;
3418 PROC_LOCK_ASSERT(p, MA_OWNED);
3419 p->p_acflag |= AXSIG;
3421 * We must be single-threading to generate a core dump. This
3422 * ensures that the registers in the core file are up-to-date.
3423 * Also, the ELF dump handler assumes that the thread list doesn't
3424 * change out from under it.
3426 * XXX If another thread attempts to single-thread before us
3427 * (e.g. via fork()), we won't get a dump at all.
3429 if ((sigprop(sig) & SIGPROP_CORE) &&
3430 thread_single(p, SINGLE_NO_EXIT) == 0) {
3433 * Log signals which would cause core dumps
3434 * (Log as LOG_INFO to appease those who don't want
3436 * XXX : Todo, as well as euid, write out ruid too
3437 * Note that coredump() drops proc lock.
3439 if (coredump(td) == 0)
3441 if (kern_logsigexit)
3443 "pid %d (%s), jid %d, uid %d: exited on "
3444 "signal %d%s\n", p->p_pid, p->p_comm,
3445 p->p_ucred->cr_prison->pr_id,
3446 td->td_ucred->cr_uid,
3448 sig & WCOREFLAG ? " (core dumped)" : "");
3456 * Send queued SIGCHLD to parent when child process's state
3460 sigparent(struct proc *p, int reason, int status)
3462 PROC_LOCK_ASSERT(p, MA_OWNED);
3463 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3465 if (p->p_ksi != NULL) {
3466 p->p_ksi->ksi_signo = SIGCHLD;
3467 p->p_ksi->ksi_code = reason;
3468 p->p_ksi->ksi_status = status;
3469 p->p_ksi->ksi_pid = p->p_pid;
3470 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3471 if (KSI_ONQ(p->p_ksi))
3474 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3478 childproc_jobstate(struct proc *p, int reason, int sig)
3482 PROC_LOCK_ASSERT(p, MA_OWNED);
3483 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3486 * Wake up parent sleeping in kern_wait(), also send
3487 * SIGCHLD to parent, but SIGCHLD does not guarantee
3488 * that parent will awake, because parent may masked
3491 p->p_pptr->p_flag |= P_STATCHILD;
3494 ps = p->p_pptr->p_sigacts;
3495 mtx_lock(&ps->ps_mtx);
3496 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3497 mtx_unlock(&ps->ps_mtx);
3498 sigparent(p, reason, sig);
3500 mtx_unlock(&ps->ps_mtx);
3504 childproc_stopped(struct proc *p, int reason)
3507 childproc_jobstate(p, reason, p->p_xsig);
3511 childproc_continued(struct proc *p)
3513 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3517 childproc_exited(struct proc *p)
3521 if (WCOREDUMP(p->p_xsig)) {
3522 reason = CLD_DUMPED;
3523 status = WTERMSIG(p->p_xsig);
3524 } else if (WIFSIGNALED(p->p_xsig)) {
3525 reason = CLD_KILLED;
3526 status = WTERMSIG(p->p_xsig);
3528 reason = CLD_EXITED;
3529 status = p->p_xexit;
3532 * XXX avoid calling wakeup(p->p_pptr), the work is
3535 sigparent(p, reason, status);
3538 #define MAX_NUM_CORE_FILES 100000
3539 #ifndef NUM_CORE_FILES
3540 #define NUM_CORE_FILES 5
3542 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3543 static int num_cores = NUM_CORE_FILES;
3546 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3551 new_val = num_cores;
3552 error = sysctl_handle_int(oidp, &new_val, 0, req);
3553 if (error != 0 || req->newptr == NULL)
3555 if (new_val > MAX_NUM_CORE_FILES)
3556 new_val = MAX_NUM_CORE_FILES;
3559 num_cores = new_val;
3562 SYSCTL_PROC(_debug, OID_AUTO, ncores,
3563 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, sizeof(int),
3564 sysctl_debug_num_cores_check, "I",
3565 "Maximum number of generated process corefiles while using index format");
3567 #define GZIP_SUFFIX ".gz"
3568 #define ZSTD_SUFFIX ".zst"
3570 int compress_user_cores = 0;
3573 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3577 val = compress_user_cores;
3578 error = sysctl_handle_int(oidp, &val, 0, req);
3579 if (error != 0 || req->newptr == NULL)
3581 if (val != 0 && !compressor_avail(val))
3583 compress_user_cores = val;
3586 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores,
3587 CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, 0, sizeof(int),
3588 sysctl_compress_user_cores, "I",
3589 "Enable compression of user corefiles ("
3590 __XSTRING(COMPRESS_GZIP) " = gzip, "
3591 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3593 int compress_user_cores_level = 6;
3594 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3595 &compress_user_cores_level, 0,
3596 "Corefile compression level");
3599 * Protect the access to corefilename[] by allproc_lock.
3601 #define corefilename_lock allproc_lock
3603 static char corefilename[MAXPATHLEN] = {"%N.core"};
3604 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3607 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3611 sx_xlock(&corefilename_lock);
3612 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3614 sx_xunlock(&corefilename_lock);
3618 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3619 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3620 "Process corefile name format string");
3623 vnode_close_locked(struct thread *td, struct vnode *vp)
3627 vn_close(vp, FWRITE, td->td_ucred, td);
3631 * If the core format has a %I in it, then we need to check
3632 * for existing corefiles before defining a name.
3633 * To do this we iterate over 0..ncores to find a
3634 * non-existing core file name to use. If all core files are
3635 * already used we choose the oldest one.
3638 corefile_open_last(struct thread *td, char *name, int indexpos,
3639 int indexlen, int ncores, struct vnode **vpp)
3641 struct vnode *oldvp, *nextvp, *vp;
3643 struct nameidata nd;
3644 int error, i, flags, oflags, cmode;
3646 struct timespec lasttime;
3648 nextvp = oldvp = NULL;
3649 cmode = S_IRUSR | S_IWUSR;
3650 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3651 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3653 for (i = 0; i < ncores; i++) {
3654 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3656 ch = name[indexpos + indexlen];
3657 (void)snprintf(name + indexpos, indexlen + 1, "%.*u", indexlen,
3659 name[indexpos + indexlen] = ch;
3661 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name);
3662 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3668 NDFREE(&nd, NDF_ONLY_PNBUF);
3669 if ((flags & O_CREAT) == O_CREAT) {
3674 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
3676 vnode_close_locked(td, vp);
3680 if (oldvp == NULL ||
3681 lasttime.tv_sec > vattr.va_mtime.tv_sec ||
3682 (lasttime.tv_sec == vattr.va_mtime.tv_sec &&
3683 lasttime.tv_nsec >= vattr.va_mtime.tv_nsec)) {
3685 vn_close(oldvp, FWRITE, td->td_ucred, td);
3688 lasttime = vattr.va_mtime;
3690 vnode_close_locked(td, vp);
3694 if (oldvp != NULL) {
3695 if (nextvp == NULL) {
3696 if ((td->td_proc->p_flag & P_SUGID) != 0) {
3698 vn_close(oldvp, FWRITE, td->td_ucred, td);
3701 error = vn_lock(nextvp, LK_EXCLUSIVE);
3703 vn_close(nextvp, FWRITE, td->td_ucred,
3709 vn_close(oldvp, FWRITE, td->td_ucred, td);
3714 vnode_close_locked(td, oldvp);
3723 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3724 * Expand the name described in corefilename, using name, uid, and pid
3725 * and open/create core file.
3726 * corefilename is a printf-like string, with three format specifiers:
3727 * %N name of process ("name")
3728 * %P process id (pid)
3730 * For example, "%N.core" is the default; they can be disabled completely
3731 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3732 * This is controlled by the sysctl variable kern.corefile (see above).
3735 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3736 int compress, int signum, struct vnode **vpp, char **namep)
3739 struct nameidata nd;
3741 char *hostname, *name;
3742 int cmode, error, flags, i, indexpos, indexlen, oflags, ncores;
3745 format = corefilename;
3746 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3750 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3751 sx_slock(&corefilename_lock);
3752 for (i = 0; format[i] != '\0'; i++) {
3753 switch (format[i]) {
3754 case '%': /* Format character */
3756 switch (format[i]) {
3758 sbuf_putc(&sb, '%');
3760 case 'H': /* hostname */
3761 if (hostname == NULL) {
3762 hostname = malloc(MAXHOSTNAMELEN,
3765 getcredhostname(td->td_ucred, hostname,
3767 sbuf_printf(&sb, "%s", hostname);
3769 case 'I': /* autoincrementing index */
3770 if (indexpos != -1) {
3771 sbuf_printf(&sb, "%%I");
3775 indexpos = sbuf_len(&sb);
3776 sbuf_printf(&sb, "%u", ncores - 1);
3777 indexlen = sbuf_len(&sb) - indexpos;
3779 case 'N': /* process name */
3780 sbuf_printf(&sb, "%s", comm);
3782 case 'P': /* process id */
3783 sbuf_printf(&sb, "%u", pid);
3785 case 'S': /* signal number */
3786 sbuf_printf(&sb, "%i", signum);
3788 case 'U': /* user id */
3789 sbuf_printf(&sb, "%u", uid);
3793 "Unknown format character %c in "
3794 "corename `%s'\n", format[i], format);
3799 sbuf_putc(&sb, format[i]);
3803 sx_sunlock(&corefilename_lock);
3804 free(hostname, M_TEMP);
3805 if (compress == COMPRESS_GZIP)
3806 sbuf_printf(&sb, GZIP_SUFFIX);
3807 else if (compress == COMPRESS_ZSTD)
3808 sbuf_printf(&sb, ZSTD_SUFFIX);
3809 if (sbuf_error(&sb) != 0) {
3810 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3811 "long\n", (long)pid, comm, (u_long)uid);
3819 if (indexpos != -1) {
3820 error = corefile_open_last(td, name, indexpos, indexlen, ncores,
3824 "pid %d (%s), uid (%u): Path `%s' failed "
3825 "on initial open test, error = %d\n",
3826 pid, comm, uid, name, error);
3829 cmode = S_IRUSR | S_IWUSR;
3830 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3831 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3832 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3833 if ((td->td_proc->p_flag & P_SUGID) != 0)
3836 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name);
3837 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3841 NDFREE(&nd, NDF_ONLY_PNBUF);
3847 audit_proc_coredump(td, name, error);
3857 * Dump a process' core. The main routine does some
3858 * policy checking, and creates the name of the coredump;
3859 * then it passes on a vnode and a size limit to the process-specific
3860 * coredump routine if there is one; if there _is not_ one, it returns
3861 * ENOSYS; otherwise it returns the error from the process-specific routine.
3865 coredump(struct thread *td)
3867 struct proc *p = td->td_proc;
3868 struct ucred *cred = td->td_ucred;
3872 size_t fullpathsize;
3873 int error, error1, locked;
3874 char *name; /* name of corefile */
3877 char *fullpath, *freepath = NULL;
3880 PROC_LOCK_ASSERT(p, MA_OWNED);
3881 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3883 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3884 (p->p_flag2 & P2_NOTRACE) != 0) {
3890 * Note that the bulk of limit checking is done after
3891 * the corefile is created. The exception is if the limit
3892 * for corefiles is 0, in which case we don't bother
3893 * creating the corefile at all. This layout means that
3894 * a corefile is truncated instead of not being created,
3895 * if it is larger than the limit.
3897 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3898 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3904 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3905 compress_user_cores, p->p_sig, &vp, &name);
3910 * Don't dump to non-regular files or files with links.
3911 * Do not dump into system files. Effective user must own the corefile.
3913 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3914 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0 ||
3915 vattr.va_uid != cred->cr_uid) {
3923 /* Postpone other writers, including core dumps of other processes. */
3924 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3926 lf.l_whence = SEEK_SET;
3929 lf.l_type = F_WRLCK;
3930 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3934 if (set_core_nodump_flag)
3935 vattr.va_flags = UF_NODUMP;
3936 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3937 VOP_SETATTR(vp, &vattr, cred);
3940 p->p_acflag |= ACORE;
3943 if (p->p_sysent->sv_coredump != NULL) {
3944 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3950 lf.l_type = F_UNLCK;
3951 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3953 vn_rangelock_unlock(vp, rl_cookie);
3956 * Notify the userland helper that a process triggered a core dump.
3957 * This allows the helper to run an automated debugging session.
3959 if (error != 0 || coredump_devctl == 0)
3961 sb = sbuf_new_auto();
3962 if (vn_fullpath_global(p->p_textvp, &fullpath, &freepath) != 0)
3964 sbuf_printf(sb, "comm=\"");
3965 devctl_safe_quote_sb(sb, fullpath);
3966 free(freepath, M_TEMP);
3967 sbuf_printf(sb, "\" core=\"");
3970 * We can't lookup core file vp directly. When we're replacing a core, and
3971 * other random times, we flush the name cache, so it will fail. Instead,
3972 * if the path of the core is relative, add the current dir in front if it.
3974 if (name[0] != '/') {
3975 fullpathsize = MAXPATHLEN;
3976 freepath = malloc(fullpathsize, M_TEMP, M_WAITOK);
3977 if (vn_getcwd(freepath, &fullpath, &fullpathsize) != 0) {
3978 free(freepath, M_TEMP);
3981 devctl_safe_quote_sb(sb, fullpath);
3982 free(freepath, M_TEMP);
3985 devctl_safe_quote_sb(sb, name);
3986 sbuf_printf(sb, "\"");
3987 if (sbuf_finish(sb) == 0)
3988 devctl_notify("kernel", "signal", "coredump", sbuf_data(sb));
3992 error1 = vn_close(vp, FWRITE, cred, td);
3996 audit_proc_coredump(td, name, error);
4003 * Nonexistent system call-- signal process (may want to handle it). Flag
4004 * error in case process won't see signal immediately (blocked or ignored).
4006 #ifndef _SYS_SYSPROTO_H_
4013 nosys(struct thread *td, struct nosys_args *args)
4020 tdsignal(td, SIGSYS);
4022 if (kern_lognosys == 1 || kern_lognosys == 3) {
4023 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
4026 if (kern_lognosys == 2 || kern_lognosys == 3 ||
4027 (p->p_pid == 1 && (kern_lognosys & 3) == 0)) {
4028 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
4035 * Send a SIGIO or SIGURG signal to a process or process group using stored
4036 * credentials rather than those of the current process.
4039 pgsigio(struct sigio **sigiop, int sig, int checkctty)
4042 struct sigio *sigio;
4044 ksiginfo_init(&ksi);
4045 ksi.ksi_signo = sig;
4046 ksi.ksi_code = SI_KERNEL;
4050 if (sigio == NULL) {
4054 if (sigio->sio_pgid > 0) {
4055 PROC_LOCK(sigio->sio_proc);
4056 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
4057 kern_psignal(sigio->sio_proc, sig);
4058 PROC_UNLOCK(sigio->sio_proc);
4059 } else if (sigio->sio_pgid < 0) {
4062 PGRP_LOCK(sigio->sio_pgrp);
4063 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
4065 if (p->p_state == PRS_NORMAL &&
4066 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
4067 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
4068 kern_psignal(p, sig);
4071 PGRP_UNLOCK(sigio->sio_pgrp);
4077 filt_sigattach(struct knote *kn)
4079 struct proc *p = curproc;
4081 kn->kn_ptr.p_proc = p;
4082 kn->kn_flags |= EV_CLEAR; /* automatically set */
4084 knlist_add(p->p_klist, kn, 0);
4090 filt_sigdetach(struct knote *kn)
4092 struct proc *p = kn->kn_ptr.p_proc;
4094 knlist_remove(p->p_klist, kn, 0);
4098 * signal knotes are shared with proc knotes, so we apply a mask to
4099 * the hint in order to differentiate them from process hints. This
4100 * could be avoided by using a signal-specific knote list, but probably
4101 * isn't worth the trouble.
4104 filt_signal(struct knote *kn, long hint)
4107 if (hint & NOTE_SIGNAL) {
4108 hint &= ~NOTE_SIGNAL;
4110 if (kn->kn_id == hint)
4113 return (kn->kn_data != 0);
4121 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
4122 refcount_init(&ps->ps_refcnt, 1);
4123 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
4128 sigacts_free(struct sigacts *ps)
4131 if (refcount_release(&ps->ps_refcnt) == 0)
4133 mtx_destroy(&ps->ps_mtx);
4134 free(ps, M_SUBPROC);
4138 sigacts_hold(struct sigacts *ps)
4141 refcount_acquire(&ps->ps_refcnt);
4146 sigacts_copy(struct sigacts *dest, struct sigacts *src)
4149 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
4150 mtx_lock(&src->ps_mtx);
4151 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
4152 mtx_unlock(&src->ps_mtx);
4156 sigacts_shared(struct sigacts *ps)
4159 return (ps->ps_refcnt > 1);
4163 sig_drop_caught(struct proc *p)
4169 PROC_LOCK_ASSERT(p, MA_OWNED);
4170 mtx_assert(&ps->ps_mtx, MA_OWNED);
4171 SIG_FOREACH(sig, &ps->ps_sigcatch) {
4173 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
4174 sigqueue_delete_proc(p, sig);
4179 sigfastblock_failed(struct thread *td, bool sendsig, bool write)
4184 * Prevent further fetches and SIGSEGVs, allowing thread to
4185 * issue syscalls despite corruption.
4187 sigfastblock_clear(td);
4191 ksiginfo_init_trap(&ksi);
4192 ksi.ksi_signo = SIGSEGV;
4193 ksi.ksi_code = write ? SEGV_ACCERR : SEGV_MAPERR;
4194 ksi.ksi_addr = td->td_sigblock_ptr;
4195 trapsignal(td, &ksi);
4199 sigfastblock_fetch_sig(struct thread *td, bool sendsig, uint32_t *valp)
4203 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0)
4205 if (fueword32((void *)td->td_sigblock_ptr, &res) == -1) {
4206 sigfastblock_failed(td, sendsig, false);
4210 td->td_sigblock_val = res & ~SIGFASTBLOCK_FLAGS;
4215 sigfastblock_resched(struct thread *td, bool resched)
4222 reschedule_signals(p, td->td_sigmask, 0);
4226 td->td_flags |= TDF_ASTPENDING | TDF_NEEDSIGCHK;
4231 sys_sigfastblock(struct thread *td, struct sigfastblock_args *uap)
4240 case SIGFASTBLOCK_SETPTR:
4241 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
4245 if (((uintptr_t)(uap->ptr) & (sizeof(uint32_t) - 1)) != 0) {
4249 td->td_pflags |= TDP_SIGFASTBLOCK;
4250 td->td_sigblock_ptr = uap->ptr;
4253 case SIGFASTBLOCK_UNBLOCK:
4254 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) {
4260 res = casueword32(td->td_sigblock_ptr,
4261 SIGFASTBLOCK_PEND, &oldval, 0);
4264 sigfastblock_failed(td, false, true);
4270 if (oldval != SIGFASTBLOCK_PEND) {
4274 error = thread_check_susp(td, false);
4282 * td_sigblock_val is cleared there, but not on a
4283 * syscall exit. The end effect is that a single
4284 * interruptible sleep, while user sigblock word is
4285 * set, might return EINTR or ERESTART to usermode
4286 * without delivering signal. All further sleeps,
4287 * until userspace clears the word and does
4288 * sigfastblock(UNBLOCK), observe current word and no
4289 * longer get interrupted. It is slight
4290 * non-conformance, with alternative to have read the
4291 * sigblock word on each syscall entry.
4293 td->td_sigblock_val = 0;
4296 * Rely on normal ast mechanism to deliver pending
4297 * signals to current thread. But notify others about
4300 sigfastblock_resched(td, error == 0 && p->p_numthreads != 1);
4304 case SIGFASTBLOCK_UNSETPTR:
4305 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) {
4309 if (!sigfastblock_fetch_sig(td, false, &oldval)) {
4313 if (oldval != 0 && oldval != SIGFASTBLOCK_PEND) {
4317 sigfastblock_clear(td);
4328 sigfastblock_clear(struct thread *td)
4332 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0)
4334 td->td_sigblock_val = 0;
4335 resched = (td->td_pflags & TDP_SIGFASTPENDING) != 0 ||
4337 td->td_pflags &= ~(TDP_SIGFASTBLOCK | TDP_SIGFASTPENDING);
4338 sigfastblock_resched(td, resched);
4342 sigfastblock_fetch(struct thread *td)
4346 (void)sigfastblock_fetch_sig(td, true, &val);
4350 sigfastblock_setpend1(struct thread *td)
4355 if ((td->td_pflags & TDP_SIGFASTPENDING) == 0)
4357 res = fueword32((void *)td->td_sigblock_ptr, &oldval);
4359 sigfastblock_failed(td, true, false);
4363 res = casueword32(td->td_sigblock_ptr, oldval, &oldval,
4364 oldval | SIGFASTBLOCK_PEND);
4366 sigfastblock_failed(td, true, true);
4370 td->td_sigblock_val = oldval & ~SIGFASTBLOCK_FLAGS;
4371 td->td_pflags &= ~TDP_SIGFASTPENDING;
4375 if (thread_check_susp(td, false) != 0)
4381 sigfastblock_setpend(struct thread *td, bool resched)
4385 sigfastblock_setpend1(td);
4389 reschedule_signals(p, fastblock_mask, SIGPROCMASK_FASTBLK);