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_capsicum.h"
43 #include "opt_ktrace.h"
45 #include <sys/param.h>
46 #include <sys/capsicum.h>
47 #include <sys/ctype.h>
48 #include <sys/systm.h>
49 #include <sys/signalvar.h>
50 #include <sys/vnode.h>
52 #include <sys/capsicum.h>
53 #include <sys/compressor.h>
54 #include <sys/condvar.h>
55 #include <sys/devctl.h>
56 #include <sys/event.h>
57 #include <sys/fcntl.h>
58 #include <sys/imgact.h>
59 #include <sys/kernel.h>
61 #include <sys/ktrace.h>
62 #include <sys/limits.h>
64 #include <sys/malloc.h>
65 #include <sys/mutex.h>
66 #include <sys/refcount.h>
67 #include <sys/namei.h>
69 #include <sys/procdesc.h>
70 #include <sys/ptrace.h>
71 #include <sys/posix4.h>
72 #include <sys/racct.h>
73 #include <sys/resourcevar.h>
76 #include <sys/sleepqueue.h>
80 #include <sys/syscall.h>
81 #include <sys/syscallsubr.h>
82 #include <sys/sysctl.h>
83 #include <sys/sysent.h>
84 #include <sys/syslog.h>
85 #include <sys/sysproto.h>
86 #include <sys/timers.h>
87 #include <sys/unistd.h>
88 #include <sys/vmmeter.h>
91 #include <vm/vm_extern.h>
96 #include <machine/cpu.h>
98 #include <security/audit/audit.h>
100 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
102 SDT_PROVIDER_DECLARE(proc);
103 SDT_PROBE_DEFINE3(proc, , , signal__send,
104 "struct thread *", "struct proc *", "int");
105 SDT_PROBE_DEFINE2(proc, , , signal__clear,
106 "int", "ksiginfo_t *");
107 SDT_PROBE_DEFINE3(proc, , , signal__discard,
108 "struct thread *", "struct proc *", "int");
110 static int coredump(struct thread *);
111 static int killpg1(struct thread *td, int sig, int pgid, int all,
113 static int issignal(struct thread *td);
114 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
115 static int sigprop(int sig);
116 static void tdsigwakeup(struct thread *, int, sig_t, int);
117 static int sig_suspend_threads(struct thread *, struct proc *, int);
118 static int filt_sigattach(struct knote *kn);
119 static void filt_sigdetach(struct knote *kn);
120 static int filt_signal(struct knote *kn, long hint);
121 static struct thread *sigtd(struct proc *p, int sig, bool fast_sigblock);
122 static void sigqueue_start(void);
124 static uma_zone_t ksiginfo_zone = NULL;
125 struct filterops sig_filtops = {
127 .f_attach = filt_sigattach,
128 .f_detach = filt_sigdetach,
129 .f_event = filt_signal,
132 static int kern_logsigexit = 1;
133 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
135 "Log processes quitting on abnormal signals to syslog(3)");
137 static int kern_forcesigexit = 1;
138 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
139 &kern_forcesigexit, 0, "Force trap signal to be handled");
141 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
142 "POSIX real time signal");
144 static int max_pending_per_proc = 128;
145 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
146 &max_pending_per_proc, 0, "Max pending signals per proc");
148 static int preallocate_siginfo = 1024;
149 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
150 &preallocate_siginfo, 0, "Preallocated signal memory size");
152 static int signal_overflow = 0;
153 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
154 &signal_overflow, 0, "Number of signals overflew");
156 static int signal_alloc_fail = 0;
157 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
158 &signal_alloc_fail, 0, "signals failed to be allocated");
160 static int kern_lognosys = 0;
161 SYSCTL_INT(_kern, OID_AUTO, lognosys, CTLFLAG_RWTUN, &kern_lognosys, 0,
162 "Log invalid syscalls");
164 __read_frequently bool sigfastblock_fetch_always = false;
165 SYSCTL_BOOL(_kern, OID_AUTO, sigfastblock_fetch_always, CTLFLAG_RWTUN,
166 &sigfastblock_fetch_always, 0,
167 "Fetch sigfastblock word on each syscall entry for proper "
168 "blocking semantic");
170 static bool kern_sig_discard_ign = true;
171 SYSCTL_BOOL(_kern, OID_AUTO, sig_discard_ign, CTLFLAG_RWTUN,
172 &kern_sig_discard_ign, 0,
173 "Discard ignored signals on delivery, otherwise queue them to "
176 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
179 * Policy -- Can ucred cr1 send SIGIO to process cr2?
180 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
181 * in the right situations.
183 #define CANSIGIO(cr1, cr2) \
184 ((cr1)->cr_uid == 0 || \
185 (cr1)->cr_ruid == (cr2)->cr_ruid || \
186 (cr1)->cr_uid == (cr2)->cr_ruid || \
187 (cr1)->cr_ruid == (cr2)->cr_uid || \
188 (cr1)->cr_uid == (cr2)->cr_uid)
190 static int sugid_coredump;
191 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
192 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
194 static int capmode_coredump;
195 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
196 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
198 static int do_coredump = 1;
199 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
200 &do_coredump, 0, "Enable/Disable coredumps");
202 static int set_core_nodump_flag = 0;
203 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
204 0, "Enable setting the NODUMP flag on coredump files");
206 static int coredump_devctl = 0;
207 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
208 0, "Generate a devctl notification when processes coredump");
211 * Signal properties and actions.
212 * The array below categorizes the signals and their default actions
213 * according to the following properties:
215 #define SIGPROP_KILL 0x01 /* terminates process by default */
216 #define SIGPROP_CORE 0x02 /* ditto and coredumps */
217 #define SIGPROP_STOP 0x04 /* suspend process */
218 #define SIGPROP_TTYSTOP 0x08 /* ditto, from tty */
219 #define SIGPROP_IGNORE 0x10 /* ignore by default */
220 #define SIGPROP_CONT 0x20 /* continue if suspended */
222 static int sigproptbl[NSIG] = {
223 [SIGHUP] = SIGPROP_KILL,
224 [SIGINT] = SIGPROP_KILL,
225 [SIGQUIT] = SIGPROP_KILL | SIGPROP_CORE,
226 [SIGILL] = SIGPROP_KILL | SIGPROP_CORE,
227 [SIGTRAP] = SIGPROP_KILL | SIGPROP_CORE,
228 [SIGABRT] = SIGPROP_KILL | SIGPROP_CORE,
229 [SIGEMT] = SIGPROP_KILL | SIGPROP_CORE,
230 [SIGFPE] = SIGPROP_KILL | SIGPROP_CORE,
231 [SIGKILL] = SIGPROP_KILL,
232 [SIGBUS] = SIGPROP_KILL | SIGPROP_CORE,
233 [SIGSEGV] = SIGPROP_KILL | SIGPROP_CORE,
234 [SIGSYS] = SIGPROP_KILL | SIGPROP_CORE,
235 [SIGPIPE] = SIGPROP_KILL,
236 [SIGALRM] = SIGPROP_KILL,
237 [SIGTERM] = SIGPROP_KILL,
238 [SIGURG] = SIGPROP_IGNORE,
239 [SIGSTOP] = SIGPROP_STOP,
240 [SIGTSTP] = SIGPROP_STOP | SIGPROP_TTYSTOP,
241 [SIGCONT] = SIGPROP_IGNORE | SIGPROP_CONT,
242 [SIGCHLD] = SIGPROP_IGNORE,
243 [SIGTTIN] = SIGPROP_STOP | SIGPROP_TTYSTOP,
244 [SIGTTOU] = SIGPROP_STOP | SIGPROP_TTYSTOP,
245 [SIGIO] = SIGPROP_IGNORE,
246 [SIGXCPU] = SIGPROP_KILL,
247 [SIGXFSZ] = SIGPROP_KILL,
248 [SIGVTALRM] = SIGPROP_KILL,
249 [SIGPROF] = SIGPROP_KILL,
250 [SIGWINCH] = SIGPROP_IGNORE,
251 [SIGINFO] = SIGPROP_IGNORE,
252 [SIGUSR1] = SIGPROP_KILL,
253 [SIGUSR2] = SIGPROP_KILL,
256 #define _SIG_FOREACH_ADVANCE(i, set) ({ \
260 int __sig = ffs(__bits); \
261 __bits &= ~(1u << (__sig - 1)); \
262 sig = __i * sizeof((set)->__bits[0]) * NBBY + __sig; \
266 if (++__i == _SIG_WORDS) { \
270 __bits = (set)->__bits[__i]; \
275 #define SIG_FOREACH(i, set) \
276 for (int32_t __i = -1, __bits = 0; \
277 _SIG_FOREACH_ADVANCE(i, set); ) \
279 sigset_t fastblock_mask;
284 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
285 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
286 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
287 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
288 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
289 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
290 SIGFILLSET(fastblock_mask);
291 SIG_CANTMASK(fastblock_mask);
295 ksiginfo_alloc(int mwait)
297 MPASS(mwait == M_WAITOK || mwait == M_NOWAIT);
299 if (ksiginfo_zone == NULL)
301 return (uma_zalloc(ksiginfo_zone, mwait | M_ZERO));
305 ksiginfo_free(ksiginfo_t *ksi)
307 uma_zfree(ksiginfo_zone, ksi);
311 ksiginfo_tryfree(ksiginfo_t *ksi)
313 if ((ksi->ksi_flags & KSI_EXT) == 0) {
314 uma_zfree(ksiginfo_zone, ksi);
321 sigqueue_init(sigqueue_t *list, struct proc *p)
323 SIGEMPTYSET(list->sq_signals);
324 SIGEMPTYSET(list->sq_kill);
325 SIGEMPTYSET(list->sq_ptrace);
326 TAILQ_INIT(&list->sq_list);
328 list->sq_flags = SQ_INIT;
332 * Get a signal's ksiginfo.
334 * 0 - signal not found
335 * others - signal number
338 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
340 struct proc *p = sq->sq_proc;
341 struct ksiginfo *ksi, *next;
344 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
346 if (!SIGISMEMBER(sq->sq_signals, signo))
349 if (SIGISMEMBER(sq->sq_ptrace, signo)) {
351 SIGDELSET(sq->sq_ptrace, signo);
352 si->ksi_flags |= KSI_PTRACE;
354 if (SIGISMEMBER(sq->sq_kill, signo)) {
357 SIGDELSET(sq->sq_kill, signo);
360 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
361 if (ksi->ksi_signo == signo) {
363 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
364 ksi->ksi_sigq = NULL;
365 ksiginfo_copy(ksi, si);
366 if (ksiginfo_tryfree(ksi) && p != NULL)
375 SIGDELSET(sq->sq_signals, signo);
376 si->ksi_signo = signo;
381 sigqueue_take(ksiginfo_t *ksi)
387 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
391 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
392 ksi->ksi_sigq = NULL;
393 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
396 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
397 kp = TAILQ_NEXT(kp, ksi_link)) {
398 if (kp->ksi_signo == ksi->ksi_signo)
401 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) &&
402 !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo))
403 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
407 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
409 struct proc *p = sq->sq_proc;
410 struct ksiginfo *ksi;
413 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
416 * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path
419 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
420 SIGADDSET(sq->sq_kill, signo);
424 /* directly insert the ksi, don't copy it */
425 if (si->ksi_flags & KSI_INS) {
426 if (si->ksi_flags & KSI_HEAD)
427 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
429 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
434 if (__predict_false(ksiginfo_zone == NULL)) {
435 SIGADDSET(sq->sq_kill, signo);
439 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
442 } else if ((ksi = ksiginfo_alloc(M_NOWAIT)) == NULL) {
448 ksiginfo_copy(si, ksi);
449 ksi->ksi_signo = signo;
450 if (si->ksi_flags & KSI_HEAD)
451 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
453 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
458 if ((si->ksi_flags & KSI_PTRACE) != 0) {
459 SIGADDSET(sq->sq_ptrace, signo);
462 } else if ((si->ksi_flags & KSI_TRAP) != 0 ||
463 (si->ksi_flags & KSI_SIGQ) == 0) {
464 SIGADDSET(sq->sq_kill, signo);
472 SIGADDSET(sq->sq_signals, signo);
477 sigqueue_flush(sigqueue_t *sq)
479 struct proc *p = sq->sq_proc;
482 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
485 PROC_LOCK_ASSERT(p, MA_OWNED);
487 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
488 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
489 ksi->ksi_sigq = NULL;
490 if (ksiginfo_tryfree(ksi) && p != NULL)
494 SIGEMPTYSET(sq->sq_signals);
495 SIGEMPTYSET(sq->sq_kill);
496 SIGEMPTYSET(sq->sq_ptrace);
500 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
503 struct proc *p1, *p2;
504 ksiginfo_t *ksi, *next;
506 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
507 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
510 /* Move siginfo to target list */
511 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
512 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
513 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
516 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
523 /* Move pending bits to target list */
525 SIGSETAND(tmp, *set);
526 SIGSETOR(dst->sq_kill, tmp);
527 SIGSETNAND(src->sq_kill, tmp);
529 tmp = src->sq_ptrace;
530 SIGSETAND(tmp, *set);
531 SIGSETOR(dst->sq_ptrace, tmp);
532 SIGSETNAND(src->sq_ptrace, tmp);
534 tmp = src->sq_signals;
535 SIGSETAND(tmp, *set);
536 SIGSETOR(dst->sq_signals, tmp);
537 SIGSETNAND(src->sq_signals, tmp);
542 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
547 SIGADDSET(set, signo);
548 sigqueue_move_set(src, dst, &set);
553 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
555 struct proc *p = sq->sq_proc;
556 ksiginfo_t *ksi, *next;
558 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
560 /* Remove siginfo queue */
561 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
562 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
563 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
564 ksi->ksi_sigq = NULL;
565 if (ksiginfo_tryfree(ksi) && p != NULL)
569 SIGSETNAND(sq->sq_kill, *set);
570 SIGSETNAND(sq->sq_ptrace, *set);
571 SIGSETNAND(sq->sq_signals, *set);
575 sigqueue_delete(sigqueue_t *sq, int signo)
580 SIGADDSET(set, signo);
581 sigqueue_delete_set(sq, &set);
584 /* Remove a set of signals for a process */
586 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
591 PROC_LOCK_ASSERT(p, MA_OWNED);
593 sigqueue_init(&worklist, NULL);
594 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
596 FOREACH_THREAD_IN_PROC(p, td0)
597 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
599 sigqueue_flush(&worklist);
603 sigqueue_delete_proc(struct proc *p, int signo)
608 SIGADDSET(set, signo);
609 sigqueue_delete_set_proc(p, &set);
613 sigqueue_delete_stopmask_proc(struct proc *p)
618 SIGADDSET(set, SIGSTOP);
619 SIGADDSET(set, SIGTSTP);
620 SIGADDSET(set, SIGTTIN);
621 SIGADDSET(set, SIGTTOU);
622 sigqueue_delete_set_proc(p, &set);
626 * Determine signal that should be delivered to thread td, the current
627 * thread, 0 if none. If there is a pending stop signal with default
628 * action, the process stops in issignal().
631 cursig(struct thread *td)
633 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
634 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
635 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
636 return (SIGPENDING(td) ? issignal(td) : 0);
640 * Arrange for ast() to handle unmasked pending signals on return to user
641 * mode. This must be called whenever a signal is added to td_sigqueue or
642 * unmasked in td_sigmask.
645 signotify(struct thread *td)
648 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
650 if (SIGPENDING(td)) {
652 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
658 * Returns 1 (true) if altstack is configured for the thread, and the
659 * passed stack bottom address falls into the altstack range. Handles
660 * the 43 compat special case where the alt stack size is zero.
663 sigonstack(size_t sp)
668 if ((td->td_pflags & TDP_ALTSTACK) == 0)
670 #if defined(COMPAT_43)
671 if (SV_PROC_FLAG(td->td_proc, SV_AOUT) && td->td_sigstk.ss_size == 0)
672 return ((td->td_sigstk.ss_flags & SS_ONSTACK) != 0);
674 return (sp >= (size_t)td->td_sigstk.ss_sp &&
675 sp < td->td_sigstk.ss_size + (size_t)td->td_sigstk.ss_sp);
682 if (sig > 0 && sig < nitems(sigproptbl))
683 return (sigproptbl[sig]);
688 sigact_flag_test(const struct sigaction *act, int flag)
692 * SA_SIGINFO is reset when signal disposition is set to
693 * ignore or default. Other flags are kept according to user
696 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
697 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
698 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
708 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
709 struct sigaction *oact, int flags)
712 struct proc *p = td->td_proc;
714 if (!_SIG_VALID(sig))
716 if (act != NULL && act->sa_handler != SIG_DFL &&
717 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
718 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
719 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
724 mtx_lock(&ps->ps_mtx);
726 memset(oact, 0, sizeof(*oact));
727 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
728 if (SIGISMEMBER(ps->ps_sigonstack, sig))
729 oact->sa_flags |= SA_ONSTACK;
730 if (!SIGISMEMBER(ps->ps_sigintr, sig))
731 oact->sa_flags |= SA_RESTART;
732 if (SIGISMEMBER(ps->ps_sigreset, sig))
733 oact->sa_flags |= SA_RESETHAND;
734 if (SIGISMEMBER(ps->ps_signodefer, sig))
735 oact->sa_flags |= SA_NODEFER;
736 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
737 oact->sa_flags |= SA_SIGINFO;
739 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
741 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
742 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
743 oact->sa_flags |= SA_NOCLDSTOP;
744 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
745 oact->sa_flags |= SA_NOCLDWAIT;
748 if ((sig == SIGKILL || sig == SIGSTOP) &&
749 act->sa_handler != SIG_DFL) {
750 mtx_unlock(&ps->ps_mtx);
756 * Change setting atomically.
759 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
760 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
761 if (sigact_flag_test(act, SA_SIGINFO)) {
762 ps->ps_sigact[_SIG_IDX(sig)] =
763 (__sighandler_t *)act->sa_sigaction;
764 SIGADDSET(ps->ps_siginfo, sig);
766 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
767 SIGDELSET(ps->ps_siginfo, sig);
769 if (!sigact_flag_test(act, SA_RESTART))
770 SIGADDSET(ps->ps_sigintr, sig);
772 SIGDELSET(ps->ps_sigintr, sig);
773 if (sigact_flag_test(act, SA_ONSTACK))
774 SIGADDSET(ps->ps_sigonstack, sig);
776 SIGDELSET(ps->ps_sigonstack, sig);
777 if (sigact_flag_test(act, SA_RESETHAND))
778 SIGADDSET(ps->ps_sigreset, sig);
780 SIGDELSET(ps->ps_sigreset, sig);
781 if (sigact_flag_test(act, SA_NODEFER))
782 SIGADDSET(ps->ps_signodefer, sig);
784 SIGDELSET(ps->ps_signodefer, sig);
785 if (sig == SIGCHLD) {
786 if (act->sa_flags & SA_NOCLDSTOP)
787 ps->ps_flag |= PS_NOCLDSTOP;
789 ps->ps_flag &= ~PS_NOCLDSTOP;
790 if (act->sa_flags & SA_NOCLDWAIT) {
792 * Paranoia: since SA_NOCLDWAIT is implemented
793 * by reparenting the dying child to PID 1 (and
794 * trust it to reap the zombie), PID 1 itself
795 * is forbidden to set SA_NOCLDWAIT.
798 ps->ps_flag &= ~PS_NOCLDWAIT;
800 ps->ps_flag |= PS_NOCLDWAIT;
802 ps->ps_flag &= ~PS_NOCLDWAIT;
803 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
804 ps->ps_flag |= PS_CLDSIGIGN;
806 ps->ps_flag &= ~PS_CLDSIGIGN;
809 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
810 * and for signals set to SIG_DFL where the default is to
811 * ignore. However, don't put SIGCONT in ps_sigignore, as we
812 * have to restart the process.
814 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
815 (sigprop(sig) & SIGPROP_IGNORE &&
816 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
817 /* never to be seen again */
818 sigqueue_delete_proc(p, sig);
820 /* easier in psignal */
821 SIGADDSET(ps->ps_sigignore, sig);
822 SIGDELSET(ps->ps_sigcatch, sig);
824 SIGDELSET(ps->ps_sigignore, sig);
825 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
826 SIGDELSET(ps->ps_sigcatch, sig);
828 SIGADDSET(ps->ps_sigcatch, sig);
830 #ifdef COMPAT_FREEBSD4
831 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
832 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
833 (flags & KSA_FREEBSD4) == 0)
834 SIGDELSET(ps->ps_freebsd4, sig);
836 SIGADDSET(ps->ps_freebsd4, sig);
839 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
840 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
841 (flags & KSA_OSIGSET) == 0)
842 SIGDELSET(ps->ps_osigset, sig);
844 SIGADDSET(ps->ps_osigset, sig);
847 mtx_unlock(&ps->ps_mtx);
852 #ifndef _SYS_SYSPROTO_H_
853 struct sigaction_args {
855 struct sigaction *act;
856 struct sigaction *oact;
860 sys_sigaction(struct thread *td, struct sigaction_args *uap)
862 struct sigaction act, oact;
863 struct sigaction *actp, *oactp;
866 actp = (uap->act != NULL) ? &act : NULL;
867 oactp = (uap->oact != NULL) ? &oact : NULL;
869 error = copyin(uap->act, actp, sizeof(act));
873 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
875 error = copyout(oactp, uap->oact, sizeof(oact));
879 #ifdef COMPAT_FREEBSD4
880 #ifndef _SYS_SYSPROTO_H_
881 struct freebsd4_sigaction_args {
883 struct sigaction *act;
884 struct sigaction *oact;
888 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
890 struct sigaction act, oact;
891 struct sigaction *actp, *oactp;
894 actp = (uap->act != NULL) ? &act : NULL;
895 oactp = (uap->oact != NULL) ? &oact : NULL;
897 error = copyin(uap->act, actp, sizeof(act));
901 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
903 error = copyout(oactp, uap->oact, sizeof(oact));
906 #endif /* COMAPT_FREEBSD4 */
908 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
909 #ifndef _SYS_SYSPROTO_H_
910 struct osigaction_args {
912 struct osigaction *nsa;
913 struct osigaction *osa;
917 osigaction(struct thread *td, struct osigaction_args *uap)
919 struct osigaction sa;
920 struct sigaction nsa, osa;
921 struct sigaction *nsap, *osap;
924 if (uap->signum <= 0 || uap->signum >= ONSIG)
927 nsap = (uap->nsa != NULL) ? &nsa : NULL;
928 osap = (uap->osa != NULL) ? &osa : NULL;
931 error = copyin(uap->nsa, &sa, sizeof(sa));
934 nsap->sa_handler = sa.sa_handler;
935 nsap->sa_flags = sa.sa_flags;
936 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
938 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
939 if (osap && !error) {
940 sa.sa_handler = osap->sa_handler;
941 sa.sa_flags = osap->sa_flags;
942 SIG2OSIG(osap->sa_mask, sa.sa_mask);
943 error = copyout(&sa, uap->osa, sizeof(sa));
948 #if !defined(__i386__)
949 /* Avoid replicating the same stub everywhere */
951 osigreturn(struct thread *td, struct osigreturn_args *uap)
954 return (nosys(td, (struct nosys_args *)uap));
957 #endif /* COMPAT_43 */
960 * Initialize signal state for process 0;
961 * set to ignore signals that are ignored by default.
964 siginit(struct proc *p)
971 mtx_lock(&ps->ps_mtx);
972 for (i = 1; i <= NSIG; i++) {
973 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
974 SIGADDSET(ps->ps_sigignore, i);
977 mtx_unlock(&ps->ps_mtx);
982 * Reset specified signal to the default disposition.
985 sigdflt(struct sigacts *ps, int sig)
988 mtx_assert(&ps->ps_mtx, MA_OWNED);
989 SIGDELSET(ps->ps_sigcatch, sig);
990 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
991 SIGADDSET(ps->ps_sigignore, sig);
992 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
993 SIGDELSET(ps->ps_siginfo, sig);
997 * Reset signals for an exec of the specified process.
1000 execsigs(struct proc *p)
1002 sigset_t osigignore;
1008 * Reset caught signals. Held signals remain held
1009 * through td_sigmask (unless they were caught,
1010 * and are now ignored by default).
1012 PROC_LOCK_ASSERT(p, MA_OWNED);
1014 mtx_lock(&ps->ps_mtx);
1018 * As CloudABI processes cannot modify signal handlers, fully
1019 * reset all signals to their default behavior. Do ignore
1020 * SIGPIPE, as it would otherwise be impossible to recover from
1021 * writes to broken pipes and sockets.
1023 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
1024 osigignore = ps->ps_sigignore;
1025 SIG_FOREACH(sig, &osigignore) {
1029 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1033 * Reset stack state to the user stack.
1034 * Clear set of signals caught on the signal stack.
1037 MPASS(td->td_proc == p);
1038 td->td_sigstk.ss_flags = SS_DISABLE;
1039 td->td_sigstk.ss_size = 0;
1040 td->td_sigstk.ss_sp = 0;
1041 td->td_pflags &= ~TDP_ALTSTACK;
1043 * Reset no zombies if child dies flag as Solaris does.
1045 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1046 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1047 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1048 mtx_unlock(&ps->ps_mtx);
1052 * kern_sigprocmask()
1054 * Manipulate signal mask.
1057 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1060 sigset_t new_block, oset1;
1065 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1066 PROC_LOCK_ASSERT(p, MA_OWNED);
1069 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1070 ? MA_OWNED : MA_NOTOWNED);
1072 *oset = td->td_sigmask;
1079 oset1 = td->td_sigmask;
1080 SIGSETOR(td->td_sigmask, *set);
1081 new_block = td->td_sigmask;
1082 SIGSETNAND(new_block, oset1);
1085 SIGSETNAND(td->td_sigmask, *set);
1090 oset1 = td->td_sigmask;
1091 if (flags & SIGPROCMASK_OLD)
1092 SIGSETLO(td->td_sigmask, *set);
1094 td->td_sigmask = *set;
1095 new_block = td->td_sigmask;
1096 SIGSETNAND(new_block, oset1);
1105 * The new_block set contains signals that were not previously
1106 * blocked, but are blocked now.
1108 * In case we block any signal that was not previously blocked
1109 * for td, and process has the signal pending, try to schedule
1110 * signal delivery to some thread that does not block the
1111 * signal, possibly waking it up.
1113 if (p->p_numthreads != 1)
1114 reschedule_signals(p, new_block, flags);
1118 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1123 #ifndef _SYS_SYSPROTO_H_
1124 struct sigprocmask_args {
1126 const sigset_t *set;
1131 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1134 sigset_t *setp, *osetp;
1137 setp = (uap->set != NULL) ? &set : NULL;
1138 osetp = (uap->oset != NULL) ? &oset : NULL;
1140 error = copyin(uap->set, setp, sizeof(set));
1144 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1145 if (osetp && !error) {
1146 error = copyout(osetp, uap->oset, sizeof(oset));
1151 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1152 #ifndef _SYS_SYSPROTO_H_
1153 struct osigprocmask_args {
1159 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1164 OSIG2SIG(uap->mask, set);
1165 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1166 SIG2OSIG(oset, td->td_retval[0]);
1169 #endif /* COMPAT_43 */
1172 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1178 error = copyin(uap->set, &set, sizeof(set));
1180 td->td_retval[0] = error;
1184 error = kern_sigtimedwait(td, set, &ksi, NULL);
1187 * sigwait() function shall not return EINTR, but
1188 * the syscall does. Non-ancient libc provides the
1189 * wrapper which hides EINTR. Otherwise, EINTR return
1190 * is used by libthr to handle required cancellation
1191 * point in the sigwait().
1193 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1195 td->td_retval[0] = error;
1199 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1200 td->td_retval[0] = error;
1205 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1208 struct timespec *timeout;
1214 error = copyin(uap->timeout, &ts, sizeof(ts));
1222 error = copyin(uap->set, &set, sizeof(set));
1226 error = kern_sigtimedwait(td, set, &ksi, timeout);
1231 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1234 td->td_retval[0] = ksi.ksi_signo;
1239 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1245 error = copyin(uap->set, &set, sizeof(set));
1249 error = kern_sigtimedwait(td, set, &ksi, NULL);
1254 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1257 td->td_retval[0] = ksi.ksi_signo;
1262 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1266 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1270 thr->td_si.si_signo = 0;
1275 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1276 struct timespec *timeout)
1279 sigset_t saved_mask, new_block;
1281 int error, sig, timevalid = 0;
1282 sbintime_t sbt, precision, tsbt;
1290 /* Ensure the sigfastblock value is up to date. */
1291 sigfastblock_fetch(td);
1293 if (timeout != NULL) {
1294 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1297 if (ts.tv_sec < INT32_MAX / 2) {
1300 precision >>= tc_precexp;
1301 if (TIMESEL(&sbt, tsbt))
1305 precision = sbt = 0;
1308 precision = sbt = 0;
1310 /* Some signals can not be waited for. */
1311 SIG_CANTMASK(waitset);
1314 saved_mask = td->td_sigmask;
1315 SIGSETNAND(td->td_sigmask, waitset);
1316 if ((p->p_sysent->sv_flags & SV_SIG_DISCIGN) != 0 ||
1317 !kern_sig_discard_ign) {
1319 td->td_flags |= TDF_SIGWAIT;
1323 mtx_lock(&ps->ps_mtx);
1325 mtx_unlock(&ps->ps_mtx);
1326 KASSERT(sig >= 0, ("sig %d", sig));
1327 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1328 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1329 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1339 * POSIX says this must be checked after looking for pending
1342 if (timeout != NULL && !timevalid) {
1352 error = msleep_sbt(&p->p_sigacts, &p->p_mtx, PPAUSE | PCATCH,
1353 "sigwait", sbt, precision, C_ABSOLUTE);
1355 /* The syscalls can not be restarted. */
1356 if (error == ERESTART)
1360 * If PTRACE_SCE or PTRACE_SCX were set after
1361 * userspace entered the syscall, return spurious
1362 * EINTR after wait was done. Only do this as last
1363 * resort after rechecking for possible queued signals
1364 * and expired timeouts.
1366 if (error == 0 && (p->p_ptevents & PTRACE_SYSCALL) != 0)
1370 td->td_flags &= ~TDF_SIGWAIT;
1373 new_block = saved_mask;
1374 SIGSETNAND(new_block, td->td_sigmask);
1375 td->td_sigmask = saved_mask;
1377 * Fewer signals can be delivered to us, reschedule signal
1380 if (p->p_numthreads != 1)
1381 reschedule_signals(p, new_block, 0);
1384 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1386 if (ksi->ksi_code == SI_TIMER)
1387 itimer_accept(p, ksi->ksi_timerid, ksi);
1390 if (KTRPOINT(td, KTR_PSIG)) {
1393 mtx_lock(&ps->ps_mtx);
1394 action = ps->ps_sigact[_SIG_IDX(sig)];
1395 mtx_unlock(&ps->ps_mtx);
1396 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1399 if (sig == SIGKILL) {
1400 proc_td_siginfo_capture(td, &ksi->ksi_info);
1408 #ifndef _SYS_SYSPROTO_H_
1409 struct sigpending_args {
1414 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1416 struct proc *p = td->td_proc;
1420 pending = p->p_sigqueue.sq_signals;
1421 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1423 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1426 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1427 #ifndef _SYS_SYSPROTO_H_
1428 struct osigpending_args {
1433 osigpending(struct thread *td, struct osigpending_args *uap)
1435 struct proc *p = td->td_proc;
1439 pending = p->p_sigqueue.sq_signals;
1440 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1442 SIG2OSIG(pending, td->td_retval[0]);
1445 #endif /* COMPAT_43 */
1447 #if defined(COMPAT_43)
1449 * Generalized interface signal handler, 4.3-compatible.
1451 #ifndef _SYS_SYSPROTO_H_
1452 struct osigvec_args {
1460 osigvec(struct thread *td, struct osigvec_args *uap)
1463 struct sigaction nsa, osa;
1464 struct sigaction *nsap, *osap;
1467 if (uap->signum <= 0 || uap->signum >= ONSIG)
1469 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1470 osap = (uap->osv != NULL) ? &osa : NULL;
1472 error = copyin(uap->nsv, &vec, sizeof(vec));
1475 nsap->sa_handler = vec.sv_handler;
1476 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1477 nsap->sa_flags = vec.sv_flags;
1478 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1480 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1481 if (osap && !error) {
1482 vec.sv_handler = osap->sa_handler;
1483 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1484 vec.sv_flags = osap->sa_flags;
1485 vec.sv_flags &= ~SA_NOCLDWAIT;
1486 vec.sv_flags ^= SA_RESTART;
1487 error = copyout(&vec, uap->osv, sizeof(vec));
1492 #ifndef _SYS_SYSPROTO_H_
1493 struct osigblock_args {
1498 osigblock(struct thread *td, struct osigblock_args *uap)
1502 OSIG2SIG(uap->mask, set);
1503 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1504 SIG2OSIG(oset, td->td_retval[0]);
1508 #ifndef _SYS_SYSPROTO_H_
1509 struct osigsetmask_args {
1514 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1518 OSIG2SIG(uap->mask, set);
1519 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1520 SIG2OSIG(oset, td->td_retval[0]);
1523 #endif /* COMPAT_43 */
1526 * Suspend calling thread until signal, providing mask to be set in the
1529 #ifndef _SYS_SYSPROTO_H_
1530 struct sigsuspend_args {
1531 const sigset_t *sigmask;
1536 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1541 error = copyin(uap->sigmask, &mask, sizeof(mask));
1544 return (kern_sigsuspend(td, mask));
1548 kern_sigsuspend(struct thread *td, sigset_t mask)
1550 struct proc *p = td->td_proc;
1553 /* Ensure the sigfastblock value is up to date. */
1554 sigfastblock_fetch(td);
1557 * When returning from sigsuspend, we want
1558 * the old mask to be restored after the
1559 * signal handler has finished. Thus, we
1560 * save it here and mark the sigacts structure
1564 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1565 SIGPROCMASK_PROC_LOCKED);
1566 td->td_pflags |= TDP_OLDMASK;
1569 * Process signals now. Otherwise, we can get spurious wakeup
1570 * due to signal entered process queue, but delivered to other
1571 * thread. But sigsuspend should return only on signal
1574 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1575 for (has_sig = 0; !has_sig;) {
1576 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1579 thread_suspend_check(0);
1580 mtx_lock(&p->p_sigacts->ps_mtx);
1581 while ((sig = cursig(td)) != 0) {
1582 KASSERT(sig >= 0, ("sig %d", sig));
1583 has_sig += postsig(sig);
1585 mtx_unlock(&p->p_sigacts->ps_mtx);
1588 * If PTRACE_SCE or PTRACE_SCX were set after
1589 * userspace entered the syscall, return spurious
1592 if ((p->p_ptevents & PTRACE_SYSCALL) != 0)
1596 td->td_errno = EINTR;
1597 td->td_pflags |= TDP_NERRNO;
1598 return (EJUSTRETURN);
1601 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1603 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1604 * convention: libc stub passes mask, not pointer, to save a copyin.
1606 #ifndef _SYS_SYSPROTO_H_
1607 struct osigsuspend_args {
1613 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1617 OSIG2SIG(uap->mask, mask);
1618 return (kern_sigsuspend(td, mask));
1620 #endif /* COMPAT_43 */
1622 #if defined(COMPAT_43)
1623 #ifndef _SYS_SYSPROTO_H_
1624 struct osigstack_args {
1625 struct sigstack *nss;
1626 struct sigstack *oss;
1631 osigstack(struct thread *td, struct osigstack_args *uap)
1633 struct sigstack nss, oss;
1636 if (uap->nss != NULL) {
1637 error = copyin(uap->nss, &nss, sizeof(nss));
1641 oss.ss_sp = td->td_sigstk.ss_sp;
1642 oss.ss_onstack = sigonstack(cpu_getstack(td));
1643 if (uap->nss != NULL) {
1644 td->td_sigstk.ss_sp = nss.ss_sp;
1645 td->td_sigstk.ss_size = 0;
1646 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1647 td->td_pflags |= TDP_ALTSTACK;
1649 if (uap->oss != NULL)
1650 error = copyout(&oss, uap->oss, sizeof(oss));
1654 #endif /* COMPAT_43 */
1656 #ifndef _SYS_SYSPROTO_H_
1657 struct sigaltstack_args {
1664 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1669 if (uap->ss != NULL) {
1670 error = copyin(uap->ss, &ss, sizeof(ss));
1674 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1675 (uap->oss != NULL) ? &oss : NULL);
1678 if (uap->oss != NULL)
1679 error = copyout(&oss, uap->oss, sizeof(stack_t));
1684 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1686 struct proc *p = td->td_proc;
1689 oonstack = sigonstack(cpu_getstack(td));
1692 *oss = td->td_sigstk;
1693 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1694 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1700 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1702 if (!(ss->ss_flags & SS_DISABLE)) {
1703 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1706 td->td_sigstk = *ss;
1707 td->td_pflags |= TDP_ALTSTACK;
1709 td->td_pflags &= ~TDP_ALTSTACK;
1715 struct killpg1_ctx {
1725 killpg1_sendsig(struct proc *p, bool notself, struct killpg1_ctx *arg)
1729 if (p->p_pid <= 1 || (p->p_flag & P_SYSTEM) != 0 ||
1730 (notself && p == arg->td->td_proc) || p->p_state == PRS_NEW)
1733 err = p_cansignal(arg->td, p, arg->sig);
1734 if (err == 0 && arg->sig != 0)
1735 pksignal(p, arg->sig, arg->ksi);
1741 else if (arg->ret == 0 && err != ESRCH && err != EPERM)
1746 * Common code for kill process group/broadcast kill.
1747 * cp is calling process.
1750 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1754 struct killpg1_ctx arg;
1766 sx_slock(&allproc_lock);
1767 FOREACH_PROC_IN_SYSTEM(p) {
1768 killpg1_sendsig(p, true, &arg);
1770 sx_sunlock(&allproc_lock);
1772 sx_slock(&proctree_lock);
1775 * zero pgid means send to my process group.
1777 pgrp = td->td_proc->p_pgrp;
1780 pgrp = pgfind(pgid);
1782 sx_sunlock(&proctree_lock);
1786 sx_sunlock(&proctree_lock);
1787 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1788 killpg1_sendsig(p, false, &arg);
1792 MPASS(arg.ret != 0 || arg.found || !arg.sent);
1793 if (arg.ret == 0 && !arg.sent)
1794 arg.ret = arg.found ? EPERM : ESRCH;
1798 #ifndef _SYS_SYSPROTO_H_
1806 sys_kill(struct thread *td, struct kill_args *uap)
1809 return (kern_kill(td, uap->pid, uap->signum));
1813 kern_kill(struct thread *td, pid_t pid, int signum)
1820 * A process in capability mode can send signals only to himself.
1821 * The main rationale behind this is that abort(3) is implemented as
1822 * kill(getpid(), SIGABRT).
1824 if (IN_CAPABILITY_MODE(td) && pid != td->td_proc->p_pid)
1827 AUDIT_ARG_SIGNUM(signum);
1829 if ((u_int)signum > _SIG_MAXSIG)
1832 ksiginfo_init(&ksi);
1833 ksi.ksi_signo = signum;
1834 ksi.ksi_code = SI_USER;
1835 ksi.ksi_pid = td->td_proc->p_pid;
1836 ksi.ksi_uid = td->td_ucred->cr_ruid;
1839 /* kill single process */
1840 if ((p = pfind_any(pid)) == NULL)
1842 AUDIT_ARG_PROCESS(p);
1843 error = p_cansignal(td, p, signum);
1844 if (error == 0 && signum)
1845 pksignal(p, signum, &ksi);
1850 case -1: /* broadcast signal */
1851 return (killpg1(td, signum, 0, 1, &ksi));
1852 case 0: /* signal own process group */
1853 return (killpg1(td, signum, 0, 0, &ksi));
1854 default: /* negative explicit process group */
1855 return (killpg1(td, signum, -pid, 0, &ksi));
1861 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1866 AUDIT_ARG_SIGNUM(uap->signum);
1867 AUDIT_ARG_FD(uap->fd);
1868 if ((u_int)uap->signum > _SIG_MAXSIG)
1871 error = procdesc_find(td, uap->fd, &cap_pdkill_rights, &p);
1874 AUDIT_ARG_PROCESS(p);
1875 error = p_cansignal(td, p, uap->signum);
1876 if (error == 0 && uap->signum)
1877 kern_psignal(p, uap->signum);
1882 #if defined(COMPAT_43)
1883 #ifndef _SYS_SYSPROTO_H_
1884 struct okillpg_args {
1891 okillpg(struct thread *td, struct okillpg_args *uap)
1895 AUDIT_ARG_SIGNUM(uap->signum);
1896 AUDIT_ARG_PID(uap->pgid);
1897 if ((u_int)uap->signum > _SIG_MAXSIG)
1900 ksiginfo_init(&ksi);
1901 ksi.ksi_signo = uap->signum;
1902 ksi.ksi_code = SI_USER;
1903 ksi.ksi_pid = td->td_proc->p_pid;
1904 ksi.ksi_uid = td->td_ucred->cr_ruid;
1905 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1907 #endif /* COMPAT_43 */
1909 #ifndef _SYS_SYSPROTO_H_
1910 struct sigqueue_args {
1913 /* union sigval */ void *value;
1917 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1921 sv.sival_ptr = uap->value;
1923 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1927 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1933 if ((u_int)signum > _SIG_MAXSIG)
1937 * Specification says sigqueue can only send signal to
1943 if ((p = pfind_any(pid)) == NULL)
1945 error = p_cansignal(td, p, signum);
1946 if (error == 0 && signum != 0) {
1947 ksiginfo_init(&ksi);
1948 ksi.ksi_flags = KSI_SIGQ;
1949 ksi.ksi_signo = signum;
1950 ksi.ksi_code = SI_QUEUE;
1951 ksi.ksi_pid = td->td_proc->p_pid;
1952 ksi.ksi_uid = td->td_ucred->cr_ruid;
1953 ksi.ksi_value = *value;
1954 error = pksignal(p, ksi.ksi_signo, &ksi);
1961 * Send a signal to a process group.
1964 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1969 sx_slock(&proctree_lock);
1970 pgrp = pgfind(pgid);
1971 sx_sunlock(&proctree_lock);
1973 pgsignal(pgrp, sig, 0, ksi);
1980 * Send a signal to a process group. If checktty is 1,
1981 * limit to members which have a controlling terminal.
1984 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1989 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1990 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1992 if (p->p_state == PRS_NORMAL &&
1993 (checkctty == 0 || p->p_flag & P_CONTROLT))
1994 pksignal(p, sig, ksi);
2001 * Recalculate the signal mask and reset the signal disposition after
2002 * usermode frame for delivery is formed. Should be called after
2003 * mach-specific routine, because sysent->sv_sendsig() needs correct
2004 * ps_siginfo and signal mask.
2007 postsig_done(int sig, struct thread *td, struct sigacts *ps)
2011 mtx_assert(&ps->ps_mtx, MA_OWNED);
2012 td->td_ru.ru_nsignals++;
2013 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2014 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2015 SIGADDSET(mask, sig);
2016 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2017 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2018 if (SIGISMEMBER(ps->ps_sigreset, sig))
2023 * Send a signal caused by a trap to the current thread. If it will be
2024 * caught immediately, deliver it with correct code. Otherwise, post it
2028 trapsignal(struct thread *td, ksiginfo_t *ksi)
2036 sig = ksi->ksi_signo;
2037 code = ksi->ksi_code;
2038 KASSERT(_SIG_VALID(sig), ("invalid signal"));
2040 sigfastblock_fetch(td);
2043 mtx_lock(&ps->ps_mtx);
2044 sigmask = td->td_sigmask;
2045 if (td->td_sigblock_val != 0)
2046 SIGSETOR(sigmask, fastblock_mask);
2047 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
2048 !SIGISMEMBER(sigmask, sig)) {
2050 if (KTRPOINT(curthread, KTR_PSIG))
2051 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
2052 &td->td_sigmask, code);
2054 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
2055 ksi, &td->td_sigmask);
2056 postsig_done(sig, td, ps);
2057 mtx_unlock(&ps->ps_mtx);
2060 * Avoid a possible infinite loop if the thread
2061 * masking the signal or process is ignoring the
2064 if (kern_forcesigexit && (SIGISMEMBER(sigmask, sig) ||
2065 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
2066 SIGDELSET(td->td_sigmask, sig);
2067 SIGDELSET(ps->ps_sigcatch, sig);
2068 SIGDELSET(ps->ps_sigignore, sig);
2069 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2070 td->td_pflags &= ~TDP_SIGFASTBLOCK;
2071 td->td_sigblock_val = 0;
2073 mtx_unlock(&ps->ps_mtx);
2074 p->p_sig = sig; /* XXX to verify code */
2075 tdsendsignal(p, td, sig, ksi);
2080 static struct thread *
2081 sigtd(struct proc *p, int sig, bool fast_sigblock)
2083 struct thread *td, *signal_td;
2085 PROC_LOCK_ASSERT(p, MA_OWNED);
2086 MPASS(!fast_sigblock || p == curproc);
2089 * Check if current thread can handle the signal without
2090 * switching context to another thread.
2092 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig) &&
2093 (!fast_sigblock || curthread->td_sigblock_val == 0))
2096 FOREACH_THREAD_IN_PROC(p, td) {
2097 if (!SIGISMEMBER(td->td_sigmask, sig) && (!fast_sigblock ||
2098 td != curthread || td->td_sigblock_val == 0)) {
2103 if (signal_td == NULL)
2104 signal_td = FIRST_THREAD_IN_PROC(p);
2109 * Send the signal to the process. If the signal has an action, the action
2110 * is usually performed by the target process rather than the caller; we add
2111 * the signal to the set of pending signals for the process.
2114 * o When a stop signal is sent to a sleeping process that takes the
2115 * default action, the process is stopped without awakening it.
2116 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2117 * regardless of the signal action (eg, blocked or ignored).
2119 * Other ignored signals are discarded immediately.
2121 * NB: This function may be entered from the debugger via the "kill" DDB
2122 * command. There is little that can be done to mitigate the possibly messy
2123 * side effects of this unwise possibility.
2126 kern_psignal(struct proc *p, int sig)
2130 ksiginfo_init(&ksi);
2131 ksi.ksi_signo = sig;
2132 ksi.ksi_code = SI_KERNEL;
2133 (void) tdsendsignal(p, NULL, sig, &ksi);
2137 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2140 return (tdsendsignal(p, NULL, sig, ksi));
2143 /* Utility function for finding a thread to send signal event to. */
2145 sigev_findtd(struct proc *p, struct sigevent *sigev, struct thread **ttd)
2149 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2150 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2162 tdsignal(struct thread *td, int sig)
2166 ksiginfo_init(&ksi);
2167 ksi.ksi_signo = sig;
2168 ksi.ksi_code = SI_KERNEL;
2169 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2173 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2176 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2180 sig_sleepq_abort(struct thread *td, int intrval)
2182 THREAD_LOCK_ASSERT(td, MA_OWNED);
2184 if (intrval == 0 && (td->td_flags & TDF_SIGWAIT) == 0) {
2188 return (sleepq_abort(td, intrval));
2192 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2195 sigqueue_t *sigqueue;
2202 MPASS(td == NULL || p == td->td_proc);
2203 PROC_LOCK_ASSERT(p, MA_OWNED);
2205 if (!_SIG_VALID(sig))
2206 panic("%s(): invalid signal %d", __func__, sig);
2208 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2211 * IEEE Std 1003.1-2001: return success when killing a zombie.
2213 if (p->p_state == PRS_ZOMBIE) {
2214 if (ksi != NULL && (ksi->ksi_flags & KSI_INS) != 0)
2215 ksiginfo_tryfree(ksi);
2220 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2221 prop = sigprop(sig);
2224 td = sigtd(p, sig, false);
2225 sigqueue = &p->p_sigqueue;
2227 sigqueue = &td->td_sigqueue;
2229 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2232 * If the signal is being ignored, then we forget about it
2233 * immediately, except when the target process executes
2234 * sigwait(). (Note: we don't set SIGCONT in ps_sigignore,
2235 * and if it is set to SIG_IGN, action will be SIG_DFL here.)
2237 mtx_lock(&ps->ps_mtx);
2238 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2239 if (kern_sig_discard_ign &&
2240 (p->p_sysent->sv_flags & SV_SIG_DISCIGN) == 0) {
2241 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2243 mtx_unlock(&ps->ps_mtx);
2244 if (ksi != NULL && (ksi->ksi_flags & KSI_INS) != 0)
2245 ksiginfo_tryfree(ksi);
2252 if (SIGISMEMBER(td->td_sigmask, sig))
2254 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2258 if (SIGISMEMBER(ps->ps_sigintr, sig))
2263 mtx_unlock(&ps->ps_mtx);
2265 if (prop & SIGPROP_CONT)
2266 sigqueue_delete_stopmask_proc(p);
2267 else if (prop & SIGPROP_STOP) {
2269 * If sending a tty stop signal to a member of an orphaned
2270 * process group, discard the signal here if the action
2271 * is default; don't stop the process below if sleeping,
2272 * and don't clear any pending SIGCONT.
2274 if ((prop & SIGPROP_TTYSTOP) != 0 &&
2275 (p->p_pgrp->pg_flags & PGRP_ORPHANED) != 0 &&
2276 action == SIG_DFL) {
2277 if (ksi != NULL && (ksi->ksi_flags & KSI_INS) != 0)
2278 ksiginfo_tryfree(ksi);
2281 sigqueue_delete_proc(p, SIGCONT);
2282 if (p->p_flag & P_CONTINUED) {
2283 p->p_flag &= ~P_CONTINUED;
2284 PROC_LOCK(p->p_pptr);
2285 sigqueue_take(p->p_ksi);
2286 PROC_UNLOCK(p->p_pptr);
2290 ret = sigqueue_add(sigqueue, sig, ksi);
2295 * Defer further processing for signals which are held,
2296 * except that stopped processes must be continued by SIGCONT.
2298 if (action == SIG_HOLD &&
2299 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2305 * Some signals have a process-wide effect and a per-thread
2306 * component. Most processing occurs when the process next
2307 * tries to cross the user boundary, however there are some
2308 * times when processing needs to be done immediately, such as
2309 * waking up threads so that they can cross the user boundary.
2310 * We try to do the per-process part here.
2312 if (P_SHOULDSTOP(p)) {
2313 KASSERT(!(p->p_flag & P_WEXIT),
2314 ("signal to stopped but exiting process"));
2315 if (sig == SIGKILL) {
2317 * If traced process is already stopped,
2318 * then no further action is necessary.
2320 if (p->p_flag & P_TRACED)
2323 * SIGKILL sets process running.
2324 * It will die elsewhere.
2325 * All threads must be restarted.
2327 p->p_flag &= ~P_STOPPED_SIG;
2331 if (prop & SIGPROP_CONT) {
2333 * If traced process is already stopped,
2334 * then no further action is necessary.
2336 if (p->p_flag & P_TRACED)
2339 * If SIGCONT is default (or ignored), we continue the
2340 * process but don't leave the signal in sigqueue as
2341 * it has no further action. If SIGCONT is held, we
2342 * continue the process and leave the signal in
2343 * sigqueue. If the process catches SIGCONT, let it
2344 * handle the signal itself. If it isn't waiting on
2345 * an event, it goes back to run state.
2346 * Otherwise, process goes back to sleep state.
2348 p->p_flag &= ~P_STOPPED_SIG;
2350 if (p->p_numthreads == p->p_suspcount) {
2352 p->p_flag |= P_CONTINUED;
2353 p->p_xsig = SIGCONT;
2354 PROC_LOCK(p->p_pptr);
2355 childproc_continued(p);
2356 PROC_UNLOCK(p->p_pptr);
2359 if (action == SIG_DFL) {
2360 thread_unsuspend(p);
2362 sigqueue_delete(sigqueue, sig);
2365 if (action == SIG_CATCH) {
2367 * The process wants to catch it so it needs
2368 * to run at least one thread, but which one?
2374 * The signal is not ignored or caught.
2376 thread_unsuspend(p);
2381 if (prop & SIGPROP_STOP) {
2383 * If traced process is already stopped,
2384 * then no further action is necessary.
2386 if (p->p_flag & P_TRACED)
2389 * Already stopped, don't need to stop again
2390 * (If we did the shell could get confused).
2391 * Just make sure the signal STOP bit set.
2393 p->p_flag |= P_STOPPED_SIG;
2394 sigqueue_delete(sigqueue, sig);
2399 * All other kinds of signals:
2400 * If a thread is sleeping interruptibly, simulate a
2401 * wakeup so that when it is continued it will be made
2402 * runnable and can look at the signal. However, don't make
2403 * the PROCESS runnable, leave it stopped.
2404 * It may run a bit until it hits a thread_suspend_check().
2408 if (TD_CAN_ABORT(td))
2409 wakeup_swapper = sig_sleepq_abort(td, intrval);
2415 * Mutexes are short lived. Threads waiting on them will
2416 * hit thread_suspend_check() soon.
2418 } else if (p->p_state == PRS_NORMAL) {
2419 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2420 tdsigwakeup(td, sig, action, intrval);
2424 MPASS(action == SIG_DFL);
2426 if (prop & SIGPROP_STOP) {
2427 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2429 p->p_flag |= P_STOPPED_SIG;
2432 wakeup_swapper = sig_suspend_threads(td, p, 1);
2433 if (p->p_numthreads == p->p_suspcount) {
2435 * only thread sending signal to another
2436 * process can reach here, if thread is sending
2437 * signal to its process, because thread does
2438 * not suspend itself here, p_numthreads
2439 * should never be equal to p_suspcount.
2443 sigqueue_delete_proc(p, p->p_xsig);
2449 /* Not in "NORMAL" state. discard the signal. */
2450 sigqueue_delete(sigqueue, sig);
2455 * The process is not stopped so we need to apply the signal to all the
2459 tdsigwakeup(td, sig, action, intrval);
2461 thread_unsuspend(p);
2464 itimer_proc_continue(p);
2465 kqtimer_proc_continue(p);
2467 /* If we jump here, proc slock should not be owned. */
2468 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2476 * The force of a signal has been directed against a single
2477 * thread. We need to see what we can do about knocking it
2478 * out of any sleep it may be in etc.
2481 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2483 struct proc *p = td->td_proc;
2484 int prop, wakeup_swapper;
2486 PROC_LOCK_ASSERT(p, MA_OWNED);
2487 prop = sigprop(sig);
2492 * Bring the priority of a thread up if we want it to get
2493 * killed in this lifetime. Be careful to avoid bumping the
2494 * priority of the idle thread, since we still allow to signal
2497 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2498 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2499 sched_prio(td, PUSER);
2500 if (TD_ON_SLEEPQ(td)) {
2502 * If thread is sleeping uninterruptibly
2503 * we can't interrupt the sleep... the signal will
2504 * be noticed when the process returns through
2505 * trap() or syscall().
2507 if ((td->td_flags & TDF_SINTR) == 0)
2510 * If SIGCONT is default (or ignored) and process is
2511 * asleep, we are finished; the process should not
2514 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2517 sigqueue_delete(&p->p_sigqueue, sig);
2519 * It may be on either list in this state.
2520 * Remove from both for now.
2522 sigqueue_delete(&td->td_sigqueue, sig);
2527 * Don't awaken a sleeping thread for SIGSTOP if the
2528 * STOP signal is deferred.
2530 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2531 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2535 * Give low priority threads a better chance to run.
2537 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2538 sched_prio(td, PUSER);
2540 wakeup_swapper = sig_sleepq_abort(td, intrval);
2548 * Other states do nothing with the signal immediately,
2549 * other than kicking ourselves if we are running.
2550 * It will either never be noticed, or noticed very soon.
2553 if (TD_IS_RUNNING(td) && td != curthread)
2563 ptrace_coredumpreq(struct thread *td, struct proc *p,
2564 struct thr_coredump_req *tcq)
2568 if (p->p_sysent->sv_coredump == NULL) {
2569 tcq->tc_error = ENOSYS;
2573 rl_cookie = vn_rangelock_wlock(tcq->tc_vp, 0, OFF_MAX);
2574 tcq->tc_error = p->p_sysent->sv_coredump(td, tcq->tc_vp,
2575 tcq->tc_limit, tcq->tc_flags);
2576 vn_rangelock_unlock(tcq->tc_vp, rl_cookie);
2580 ptrace_syscallreq(struct thread *td, struct proc *p,
2581 struct thr_syscall_req *tsr)
2583 struct sysentvec *sv;
2585 register_t rv_saved[2];
2588 bool audited, sy_thr_static;
2591 if (sv->sv_table == NULL || sv->sv_size < tsr->ts_sa.code) {
2592 tsr->ts_ret.sr_error = ENOSYS;
2596 sc = tsr->ts_sa.code;
2597 if (sc == SYS_syscall || sc == SYS___syscall) {
2598 sc = tsr->ts_sa.args[0];
2599 memmove(&tsr->ts_sa.args[0], &tsr->ts_sa.args[1],
2600 sizeof(register_t) * (tsr->ts_nargs - 1));
2603 tsr->ts_sa.callp = se = &sv->sv_table[sc];
2605 VM_CNT_INC(v_syscall);
2607 if (__predict_false(td->td_cowgen != atomic_load_int(
2608 &td->td_proc->p_cowgen)))
2609 thread_cow_update(td);
2611 #ifdef CAPABILITY_MODE
2612 if (IN_CAPABILITY_MODE(td) && (se->sy_flags & SYF_CAPENABLED) == 0) {
2613 tsr->ts_ret.sr_error = ECAPMODE;
2618 sy_thr_static = (se->sy_thrcnt & SY_THR_STATIC) != 0;
2619 audited = AUDIT_SYSCALL_ENTER(sc, td) != 0;
2621 if (!sy_thr_static) {
2622 error = syscall_thread_enter(td, se);
2624 tsr->ts_ret.sr_error = error;
2629 rv_saved[0] = td->td_retval[0];
2630 rv_saved[1] = td->td_retval[1];
2631 nerror = td->td_errno;
2632 td->td_retval[0] = 0;
2633 td->td_retval[1] = 0;
2635 #ifdef KDTRACE_HOOKS
2636 if (se->sy_entry != 0)
2637 (*systrace_probe_func)(&tsr->ts_sa, SYSTRACE_ENTRY, 0);
2639 tsr->ts_ret.sr_error = se->sy_call(td, tsr->ts_sa.args);
2640 #ifdef KDTRACE_HOOKS
2641 if (se->sy_return != 0)
2642 (*systrace_probe_func)(&tsr->ts_sa, SYSTRACE_RETURN,
2643 tsr->ts_ret.sr_error != 0 ? -1 : td->td_retval[0]);
2646 tsr->ts_ret.sr_retval[0] = td->td_retval[0];
2647 tsr->ts_ret.sr_retval[1] = td->td_retval[1];
2648 td->td_retval[0] = rv_saved[0];
2649 td->td_retval[1] = rv_saved[1];
2650 td->td_errno = nerror;
2653 AUDIT_SYSCALL_EXIT(error, td);
2655 syscall_thread_exit(td, se);
2659 ptrace_remotereq(struct thread *td, int flag)
2663 MPASS(td == curthread);
2665 PROC_LOCK_ASSERT(p, MA_OWNED);
2666 if ((td->td_dbgflags & flag) == 0)
2668 KASSERT((p->p_flag & P_STOPPED_TRACE) != 0, ("not stopped"));
2669 KASSERT(td->td_remotereq != NULL, ("td_remotereq is NULL"));
2673 case TDB_COREDUMPREQ:
2674 ptrace_coredumpreq(td, p, td->td_remotereq);
2676 case TDB_SCREMOTEREQ:
2677 ptrace_syscallreq(td, p, td->td_remotereq);
2684 MPASS((td->td_dbgflags & flag) != 0);
2685 td->td_dbgflags &= ~flag;
2686 td->td_remotereq = NULL;
2691 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2696 PROC_LOCK_ASSERT(p, MA_OWNED);
2697 PROC_SLOCK_ASSERT(p, MA_OWNED);
2698 MPASS(sending || td == curthread);
2701 FOREACH_THREAD_IN_PROC(p, td2) {
2703 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2704 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2705 (td2->td_flags & TDF_SINTR)) {
2706 if (td2->td_flags & TDF_SBDRY) {
2708 * Once a thread is asleep with
2709 * TDF_SBDRY and without TDF_SERESTART
2710 * or TDF_SEINTR set, it should never
2711 * become suspended due to this check.
2713 KASSERT(!TD_IS_SUSPENDED(td2),
2714 ("thread with deferred stops suspended"));
2715 if (TD_SBDRY_INTR(td2)) {
2716 wakeup_swapper |= sleepq_abort(td2,
2717 TD_SBDRY_ERRNO(td2));
2720 } else if (!TD_IS_SUSPENDED(td2))
2721 thread_suspend_one(td2);
2722 } else if (!TD_IS_SUSPENDED(td2)) {
2723 if (sending || td != td2)
2724 td2->td_flags |= TDF_ASTPENDING;
2726 if (TD_IS_RUNNING(td2) && td2 != td)
2727 forward_signal(td2);
2732 return (wakeup_swapper);
2736 * Stop the process for an event deemed interesting to the debugger. If si is
2737 * non-NULL, this is a signal exchange; the new signal requested by the
2738 * debugger will be returned for handling. If si is NULL, this is some other
2739 * type of interesting event. The debugger may request a signal be delivered in
2740 * that case as well, however it will be deferred until it can be handled.
2743 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2745 struct proc *p = td->td_proc;
2749 PROC_LOCK_ASSERT(p, MA_OWNED);
2750 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2751 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2752 &p->p_mtx.lock_object, "Stopping for traced signal");
2756 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2757 td->td_dbgflags |= TDB_XSIG;
2758 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2759 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2761 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2764 * Ensure that, if we've been PT_KILLed, the
2765 * exit status reflects that. Another thread
2766 * may also be in ptracestop(), having just
2767 * received the SIGKILL, but this thread was
2768 * unsuspended first.
2770 td->td_dbgflags &= ~TDB_XSIG;
2771 td->td_xsig = SIGKILL;
2775 if (p->p_flag & P_SINGLE_EXIT &&
2776 !(td->td_dbgflags & TDB_EXIT)) {
2778 * Ignore ptrace stops except for thread exit
2779 * events when the process exits.
2781 td->td_dbgflags &= ~TDB_XSIG;
2787 * Make wait(2) work. Ensure that right after the
2788 * attach, the thread which was decided to become the
2789 * leader of attach gets reported to the waiter.
2790 * Otherwise, just avoid overwriting another thread's
2791 * assignment to p_xthread. If another thread has
2792 * already set p_xthread, the current thread will get
2793 * a chance to report itself upon the next iteration.
2795 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2796 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2797 p->p_xthread == NULL)) {
2802 * If we are on sleepqueue already,
2803 * let sleepqueue code decide if it
2804 * needs to go sleep after attach.
2806 if (td->td_wchan == NULL)
2807 td->td_dbgflags &= ~TDB_FSTP;
2809 p->p_flag2 &= ~P2_PTRACE_FSTP;
2810 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2811 sig_suspend_threads(td, p, 0);
2813 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2814 td->td_dbgflags &= ~TDB_STOPATFORK;
2817 td->td_dbgflags |= TDB_SSWITCH;
2818 thread_suspend_switch(td, p);
2819 td->td_dbgflags &= ~TDB_SSWITCH;
2820 if ((td->td_dbgflags & (TDB_COREDUMPREQ |
2821 TDB_SCREMOTEREQ)) != 0) {
2822 MPASS((td->td_dbgflags & (TDB_COREDUMPREQ |
2823 TDB_SCREMOTEREQ)) !=
2824 (TDB_COREDUMPREQ | TDB_SCREMOTEREQ));
2826 ptrace_remotereq(td, td->td_dbgflags &
2827 (TDB_COREDUMPREQ | TDB_SCREMOTEREQ));
2831 if (p->p_xthread == td)
2832 p->p_xthread = NULL;
2833 if (!(p->p_flag & P_TRACED))
2835 if (td->td_dbgflags & TDB_SUSPEND) {
2836 if (p->p_flag & P_SINGLE_EXIT)
2844 if (si != NULL && sig == td->td_xsig) {
2845 /* Parent wants us to take the original signal unchanged. */
2846 si->ksi_flags |= KSI_HEAD;
2847 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2849 } else if (td->td_xsig != 0) {
2851 * If parent wants us to take a new signal, then it will leave
2852 * it in td->td_xsig; otherwise we just look for signals again.
2854 ksiginfo_init(&ksi);
2855 ksi.ksi_signo = td->td_xsig;
2856 ksi.ksi_flags |= KSI_PTRACE;
2857 td2 = sigtd(p, td->td_xsig, false);
2858 tdsendsignal(p, td2, td->td_xsig, &ksi);
2863 return (td->td_xsig);
2867 reschedule_signals(struct proc *p, sigset_t block, int flags)
2872 bool fastblk, pslocked;
2874 PROC_LOCK_ASSERT(p, MA_OWNED);
2876 pslocked = (flags & SIGPROCMASK_PS_LOCKED) != 0;
2877 mtx_assert(&ps->ps_mtx, pslocked ? MA_OWNED : MA_NOTOWNED);
2878 if (SIGISEMPTY(p->p_siglist))
2880 SIGSETAND(block, p->p_siglist);
2881 fastblk = (flags & SIGPROCMASK_FASTBLK) != 0;
2882 SIG_FOREACH(sig, &block) {
2883 td = sigtd(p, sig, fastblk);
2886 * If sigtd() selected us despite sigfastblock is
2887 * blocking, do not activate AST or wake us, to avoid
2888 * loop in AST handler.
2890 if (fastblk && td == curthread)
2895 mtx_lock(&ps->ps_mtx);
2896 if (p->p_flag & P_TRACED ||
2897 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2898 !SIGISMEMBER(td->td_sigmask, sig))) {
2899 tdsigwakeup(td, sig, SIG_CATCH,
2900 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2904 mtx_unlock(&ps->ps_mtx);
2909 tdsigcleanup(struct thread *td)
2915 PROC_LOCK_ASSERT(p, MA_OWNED);
2917 sigqueue_flush(&td->td_sigqueue);
2918 if (p->p_numthreads == 1)
2922 * Since we cannot handle signals, notify signal post code
2923 * about this by filling the sigmask.
2925 * Also, if needed, wake up thread(s) that do not block the
2926 * same signals as the exiting thread, since the thread might
2927 * have been selected for delivery and woken up.
2929 SIGFILLSET(unblocked);
2930 SIGSETNAND(unblocked, td->td_sigmask);
2931 SIGFILLSET(td->td_sigmask);
2932 reschedule_signals(p, unblocked, 0);
2937 sigdeferstop_curr_flags(int cflags)
2940 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2941 (cflags & TDF_SBDRY) != 0);
2942 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2946 * Defer the delivery of SIGSTOP for the current thread, according to
2947 * the requested mode. Returns previous flags, which must be restored
2948 * by sigallowstop().
2950 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2951 * cleared by the current thread, which allow the lock-less read-only
2955 sigdeferstop_impl(int mode)
2961 cflags = sigdeferstop_curr_flags(td->td_flags);
2963 case SIGDEFERSTOP_NOP:
2966 case SIGDEFERSTOP_OFF:
2969 case SIGDEFERSTOP_SILENT:
2970 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2972 case SIGDEFERSTOP_EINTR:
2973 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2975 case SIGDEFERSTOP_ERESTART:
2976 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2979 panic("sigdeferstop: invalid mode %x", mode);
2982 if (cflags == nflags)
2983 return (SIGDEFERSTOP_VAL_NCHG);
2985 td->td_flags = (td->td_flags & ~cflags) | nflags;
2991 * Restores the STOP handling mode, typically permitting the delivery
2992 * of SIGSTOP for the current thread. This does not immediately
2993 * suspend if a stop was posted. Instead, the thread will suspend
2994 * either via ast() or a subsequent interruptible sleep.
2997 sigallowstop_impl(int prev)
3002 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
3003 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
3004 ("sigallowstop: incorrect previous mode %x", prev));
3006 cflags = sigdeferstop_curr_flags(td->td_flags);
3007 if (cflags != prev) {
3009 td->td_flags = (td->td_flags & ~cflags) | prev;
3018 SIGSTATUS_SBDRY_STOP,
3022 * The thread has signal "sig" pending. Figure out what to do with it:
3024 * _HANDLE -> the caller should handle the signal
3025 * _HANDLED -> handled internally, reload pending signal set
3026 * _IGNORE -> ignored, remove from the set of pending signals and try the
3027 * next pending signal
3028 * _SBDRY_STOP -> the signal should stop the thread but this is not
3029 * permitted in the current context
3031 static enum sigstatus
3032 sigprocess(struct thread *td, int sig)
3036 struct sigqueue *queue;
3040 KASSERT(_SIG_VALID(sig), ("%s: invalid signal %d", __func__, sig));
3044 mtx_assert(&ps->ps_mtx, MA_OWNED);
3045 PROC_LOCK_ASSERT(p, MA_OWNED);
3048 * We should allow pending but ignored signals below
3049 * if there is sigwait() active, or P_TRACED was
3050 * on when they were posted.
3052 if (SIGISMEMBER(ps->ps_sigignore, sig) &&
3053 (p->p_flag & P_TRACED) == 0 &&
3054 (td->td_flags & TDF_SIGWAIT) == 0) {
3055 return (SIGSTATUS_IGNORE);
3059 * If the process is going to single-thread mode to prepare
3060 * for exit, there is no sense in delivering any signal
3061 * to usermode. Another important consequence is that
3062 * msleep(..., PCATCH, ...) now is only interruptible by a
3065 if ((p->p_flag2 & P2_WEXIT) != 0)
3066 return (SIGSTATUS_IGNORE);
3068 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
3070 * If traced, always stop.
3071 * Remove old signal from queue before the stop.
3072 * XXX shrug off debugger, it causes siginfo to
3075 queue = &td->td_sigqueue;
3076 ksiginfo_init(&ksi);
3077 if (sigqueue_get(queue, sig, &ksi) == 0) {
3078 queue = &p->p_sigqueue;
3079 sigqueue_get(queue, sig, &ksi);
3081 td->td_si = ksi.ksi_info;
3083 mtx_unlock(&ps->ps_mtx);
3084 sig = ptracestop(td, sig, &ksi);
3085 mtx_lock(&ps->ps_mtx);
3087 td->td_si.si_signo = 0;
3090 * Keep looking if the debugger discarded or
3091 * replaced the signal.
3094 return (SIGSTATUS_HANDLED);
3097 * If the signal became masked, re-queue it.
3099 if (SIGISMEMBER(td->td_sigmask, sig)) {
3100 ksi.ksi_flags |= KSI_HEAD;
3101 sigqueue_add(&p->p_sigqueue, sig, &ksi);
3102 return (SIGSTATUS_HANDLED);
3106 * If the traced bit got turned off, requeue the signal and
3107 * reload the set of pending signals. This ensures that p_sig*
3108 * and p_sigact are consistent.
3110 if ((p->p_flag & P_TRACED) == 0) {
3111 if ((ksi.ksi_flags & KSI_PTRACE) == 0) {
3112 ksi.ksi_flags |= KSI_HEAD;
3113 sigqueue_add(queue, sig, &ksi);
3115 return (SIGSTATUS_HANDLED);
3120 * Decide whether the signal should be returned.
3121 * Return the signal's number, or fall through
3122 * to clear it from the pending mask.
3124 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
3125 case (intptr_t)SIG_DFL:
3127 * Don't take default actions on system processes.
3129 if (p->p_pid <= 1) {
3132 * Are you sure you want to ignore SIGSEGV
3135 printf("Process (pid %lu) got signal %d\n",
3136 (u_long)p->p_pid, sig);
3138 return (SIGSTATUS_IGNORE);
3142 * If there is a pending stop signal to process with
3143 * default action, stop here, then clear the signal.
3144 * Traced or exiting processes should ignore stops.
3145 * Additionally, a member of an orphaned process group
3146 * should ignore tty stops.
3148 prop = sigprop(sig);
3149 if (prop & SIGPROP_STOP) {
3150 mtx_unlock(&ps->ps_mtx);
3151 if ((p->p_flag & (P_TRACED | P_WEXIT |
3152 P_SINGLE_EXIT)) != 0 || ((p->p_pgrp->
3153 pg_flags & PGRP_ORPHANED) != 0 &&
3154 (prop & SIGPROP_TTYSTOP) != 0)) {
3155 mtx_lock(&ps->ps_mtx);
3156 return (SIGSTATUS_IGNORE);
3158 if (TD_SBDRY_INTR(td)) {
3159 KASSERT((td->td_flags & TDF_SBDRY) != 0,
3160 ("lost TDF_SBDRY"));
3161 mtx_lock(&ps->ps_mtx);
3162 return (SIGSTATUS_SBDRY_STOP);
3164 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
3165 &p->p_mtx.lock_object, "Catching SIGSTOP");
3166 sigqueue_delete(&td->td_sigqueue, sig);
3167 sigqueue_delete(&p->p_sigqueue, sig);
3168 p->p_flag |= P_STOPPED_SIG;
3171 sig_suspend_threads(td, p, 0);
3172 thread_suspend_switch(td, p);
3174 mtx_lock(&ps->ps_mtx);
3175 return (SIGSTATUS_HANDLED);
3176 } else if ((prop & SIGPROP_IGNORE) != 0 &&
3177 (td->td_flags & TDF_SIGWAIT) == 0) {
3179 * Default action is to ignore; drop it if
3180 * not in kern_sigtimedwait().
3182 return (SIGSTATUS_IGNORE);
3184 return (SIGSTATUS_HANDLE);
3187 case (intptr_t)SIG_IGN:
3188 if ((td->td_flags & TDF_SIGWAIT) == 0)
3189 return (SIGSTATUS_IGNORE);
3191 return (SIGSTATUS_HANDLE);
3195 * This signal has an action, let postsig() process it.
3197 return (SIGSTATUS_HANDLE);
3202 * If the current process has received a signal (should be caught or cause
3203 * termination, should interrupt current syscall), return the signal number.
3204 * Stop signals with default action are processed immediately, then cleared;
3205 * they aren't returned. This is checked after each entry to the system for
3206 * a syscall or trap (though this can usually be done without calling
3207 * issignal by checking the pending signal masks in cursig.) The normal call
3210 * while (sig = cursig(curthread))
3214 issignal(struct thread *td)
3217 sigset_t sigpending;
3221 PROC_LOCK_ASSERT(p, MA_OWNED);
3224 sigpending = td->td_sigqueue.sq_signals;
3225 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
3226 SIGSETNAND(sigpending, td->td_sigmask);
3228 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
3229 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
3230 SIG_STOPSIGMASK(sigpending);
3231 if (SIGISEMPTY(sigpending)) /* no signal to send */
3235 * Do fast sigblock if requested by usermode. Since
3236 * we do know that there was a signal pending at this
3237 * point, set the FAST_SIGBLOCK_PEND as indicator for
3238 * usermode to perform a dummy call to
3239 * FAST_SIGBLOCK_UNBLOCK, which causes immediate
3240 * delivery of postponed pending signal.
3242 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
3243 if (td->td_sigblock_val != 0)
3244 SIGSETNAND(sigpending, fastblock_mask);
3245 if (SIGISEMPTY(sigpending)) {
3246 td->td_pflags |= TDP_SIGFASTPENDING;
3251 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
3252 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
3253 SIGISMEMBER(sigpending, SIGSTOP)) {
3255 * If debugger just attached, always consume
3256 * SIGSTOP from ptrace(PT_ATTACH) first, to
3257 * execute the debugger attach ritual in
3260 td->td_dbgflags |= TDB_FSTP;
3261 SIGEMPTYSET(sigpending);
3262 SIGADDSET(sigpending, SIGSTOP);
3265 SIG_FOREACH(sig, &sigpending) {
3266 switch (sigprocess(td, sig)) {
3267 case SIGSTATUS_HANDLE:
3269 case SIGSTATUS_HANDLED:
3271 case SIGSTATUS_IGNORE:
3272 sigqueue_delete(&td->td_sigqueue, sig);
3273 sigqueue_delete(&p->p_sigqueue, sig);
3275 case SIGSTATUS_SBDRY_STOP:
3284 thread_stopped(struct proc *p)
3288 PROC_LOCK_ASSERT(p, MA_OWNED);
3289 PROC_SLOCK_ASSERT(p, MA_OWNED);
3293 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
3295 p->p_flag &= ~P_WAITED;
3296 PROC_LOCK(p->p_pptr);
3297 childproc_stopped(p, (p->p_flag & P_TRACED) ?
3298 CLD_TRAPPED : CLD_STOPPED);
3299 PROC_UNLOCK(p->p_pptr);
3305 * Take the action for the specified signal
3306 * from the current set of pending signals.
3316 sigset_t returnmask;
3318 KASSERT(sig != 0, ("postsig"));
3322 PROC_LOCK_ASSERT(p, MA_OWNED);
3324 mtx_assert(&ps->ps_mtx, MA_OWNED);
3325 ksiginfo_init(&ksi);
3326 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3327 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3329 ksi.ksi_signo = sig;
3330 if (ksi.ksi_code == SI_TIMER)
3331 itimer_accept(p, ksi.ksi_timerid, &ksi);
3332 action = ps->ps_sigact[_SIG_IDX(sig)];
3334 if (KTRPOINT(td, KTR_PSIG))
3335 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3336 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3339 if (action == SIG_DFL) {
3341 * Default action, where the default is to kill
3342 * the process. (Other cases were ignored above.)
3344 mtx_unlock(&ps->ps_mtx);
3345 proc_td_siginfo_capture(td, &ksi.ksi_info);
3350 * If we get here, the signal must be caught.
3352 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3353 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3354 ("postsig action: blocked sig %d", sig));
3357 * Set the new mask value and also defer further
3358 * occurrences of this signal.
3360 * Special case: user has done a sigsuspend. Here the
3361 * current mask is not of interest, but rather the
3362 * mask from before the sigsuspend is what we want
3363 * restored after the signal processing is completed.
3365 if (td->td_pflags & TDP_OLDMASK) {
3366 returnmask = td->td_oldsigmask;
3367 td->td_pflags &= ~TDP_OLDMASK;
3369 returnmask = td->td_sigmask;
3371 if (p->p_sig == sig) {
3374 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3375 postsig_done(sig, td, ps);
3381 sig_ast_checksusp(struct thread *td)
3383 struct proc *p __diagused;
3387 PROC_LOCK_ASSERT(p, MA_OWNED);
3389 if ((td->td_flags & TDF_NEEDSUSPCHK) == 0)
3392 ret = thread_suspend_check(1);
3393 MPASS(ret == 0 || ret == EINTR || ret == ERESTART);
3398 sig_ast_needsigchk(struct thread *td)
3405 PROC_LOCK_ASSERT(p, MA_OWNED);
3407 if ((td->td_flags & TDF_NEEDSIGCHK) == 0)
3411 mtx_lock(&ps->ps_mtx);
3414 mtx_unlock(&ps->ps_mtx);
3415 KASSERT((td->td_flags & TDF_SBDRY) != 0, ("lost TDF_SBDRY"));
3416 KASSERT(TD_SBDRY_INTR(td),
3417 ("lost TDF_SERESTART of TDF_SEINTR"));
3418 KASSERT((td->td_flags & (TDF_SEINTR | TDF_SERESTART)) !=
3419 (TDF_SEINTR | TDF_SERESTART),
3420 ("both TDF_SEINTR and TDF_SERESTART"));
3421 ret = TD_SBDRY_ERRNO(td);
3422 } else if (sig != 0) {
3423 ret = SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR : ERESTART;
3424 mtx_unlock(&ps->ps_mtx);
3426 mtx_unlock(&ps->ps_mtx);
3431 * Do not go into sleep if this thread was the ptrace(2)
3432 * attach leader. cursig() consumed SIGSTOP from PT_ATTACH,
3433 * but we usually act on the signal by interrupting sleep, and
3434 * should do that here as well.
3436 if ((td->td_dbgflags & TDB_FSTP) != 0) {
3439 td->td_dbgflags &= ~TDB_FSTP;
3453 if ((td->td_flags & (TDF_NEEDSIGCHK | TDF_NEEDSUSPCHK)) == 0)
3459 ret = sig_ast_checksusp(td);
3461 ret = sig_ast_needsigchk(td);
3467 curproc_sigkilled(void)
3475 if ((td->td_flags & TDF_NEEDSIGCHK) == 0)
3481 mtx_lock(&ps->ps_mtx);
3482 res = SIGISMEMBER(td->td_sigqueue.sq_signals, SIGKILL) ||
3483 SIGISMEMBER(p->p_sigqueue.sq_signals, SIGKILL);
3484 mtx_unlock(&ps->ps_mtx);
3490 proc_wkilled(struct proc *p)
3493 PROC_LOCK_ASSERT(p, MA_OWNED);
3494 if ((p->p_flag & P_WKILLED) == 0) {
3495 p->p_flag |= P_WKILLED;
3497 * Notify swapper that there is a process to swap in.
3498 * The notification is racy, at worst it would take 10
3499 * seconds for the swapper process to notice.
3501 if ((p->p_flag & (P_INMEM | P_SWAPPINGIN)) == 0)
3507 * Kill the current process for stated reason.
3510 killproc(struct proc *p, const char *why)
3513 PROC_LOCK_ASSERT(p, MA_OWNED);
3514 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3516 log(LOG_ERR, "pid %d (%s), jid %d, uid %d, was killed: %s\n",
3517 p->p_pid, p->p_comm, p->p_ucred->cr_prison->pr_id,
3518 p->p_ucred->cr_uid, why);
3520 kern_psignal(p, SIGKILL);
3524 * Force the current process to exit with the specified signal, dumping core
3525 * if appropriate. We bypass the normal tests for masked and caught signals,
3526 * allowing unrecoverable failures to terminate the process without changing
3527 * signal state. Mark the accounting record with the signal termination.
3528 * If dumping core, save the signal number for the debugger. Calls exit and
3532 sigexit(struct thread *td, int sig)
3534 struct proc *p = td->td_proc;
3536 PROC_LOCK_ASSERT(p, MA_OWNED);
3537 proc_set_p2_wexit(p);
3539 p->p_acflag |= AXSIG;
3541 * We must be single-threading to generate a core dump. This
3542 * ensures that the registers in the core file are up-to-date.
3543 * Also, the ELF dump handler assumes that the thread list doesn't
3544 * change out from under it.
3546 * XXX If another thread attempts to single-thread before us
3547 * (e.g. via fork()), we won't get a dump at all.
3549 if ((sigprop(sig) & SIGPROP_CORE) &&
3550 thread_single(p, SINGLE_NO_EXIT) == 0) {
3553 * Log signals which would cause core dumps
3554 * (Log as LOG_INFO to appease those who don't want
3556 * XXX : Todo, as well as euid, write out ruid too
3557 * Note that coredump() drops proc lock.
3559 if (coredump(td) == 0)
3561 if (kern_logsigexit)
3563 "pid %d (%s), jid %d, uid %d: exited on "
3564 "signal %d%s\n", p->p_pid, p->p_comm,
3565 p->p_ucred->cr_prison->pr_id,
3566 td->td_ucred->cr_uid,
3568 sig & WCOREFLAG ? " (core dumped)" : "");
3576 * Send queued SIGCHLD to parent when child process's state
3580 sigparent(struct proc *p, int reason, int status)
3582 PROC_LOCK_ASSERT(p, MA_OWNED);
3583 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3585 if (p->p_ksi != NULL) {
3586 p->p_ksi->ksi_signo = SIGCHLD;
3587 p->p_ksi->ksi_code = reason;
3588 p->p_ksi->ksi_status = status;
3589 p->p_ksi->ksi_pid = p->p_pid;
3590 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3591 if (KSI_ONQ(p->p_ksi))
3594 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3598 childproc_jobstate(struct proc *p, int reason, int sig)
3602 PROC_LOCK_ASSERT(p, MA_OWNED);
3603 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3606 * Wake up parent sleeping in kern_wait(), also send
3607 * SIGCHLD to parent, but SIGCHLD does not guarantee
3608 * that parent will awake, because parent may masked
3611 p->p_pptr->p_flag |= P_STATCHILD;
3614 ps = p->p_pptr->p_sigacts;
3615 mtx_lock(&ps->ps_mtx);
3616 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3617 mtx_unlock(&ps->ps_mtx);
3618 sigparent(p, reason, sig);
3620 mtx_unlock(&ps->ps_mtx);
3624 childproc_stopped(struct proc *p, int reason)
3627 childproc_jobstate(p, reason, p->p_xsig);
3631 childproc_continued(struct proc *p)
3633 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3637 childproc_exited(struct proc *p)
3641 if (WCOREDUMP(p->p_xsig)) {
3642 reason = CLD_DUMPED;
3643 status = WTERMSIG(p->p_xsig);
3644 } else if (WIFSIGNALED(p->p_xsig)) {
3645 reason = CLD_KILLED;
3646 status = WTERMSIG(p->p_xsig);
3648 reason = CLD_EXITED;
3649 status = p->p_xexit;
3652 * XXX avoid calling wakeup(p->p_pptr), the work is
3655 sigparent(p, reason, status);
3658 #define MAX_NUM_CORE_FILES 100000
3659 #ifndef NUM_CORE_FILES
3660 #define NUM_CORE_FILES 5
3662 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3663 static int num_cores = NUM_CORE_FILES;
3666 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3671 new_val = num_cores;
3672 error = sysctl_handle_int(oidp, &new_val, 0, req);
3673 if (error != 0 || req->newptr == NULL)
3675 if (new_val > MAX_NUM_CORE_FILES)
3676 new_val = MAX_NUM_CORE_FILES;
3679 num_cores = new_val;
3682 SYSCTL_PROC(_debug, OID_AUTO, ncores,
3683 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, sizeof(int),
3684 sysctl_debug_num_cores_check, "I",
3685 "Maximum number of generated process corefiles while using index format");
3687 #define GZIP_SUFFIX ".gz"
3688 #define ZSTD_SUFFIX ".zst"
3690 int compress_user_cores = 0;
3693 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3697 val = compress_user_cores;
3698 error = sysctl_handle_int(oidp, &val, 0, req);
3699 if (error != 0 || req->newptr == NULL)
3701 if (val != 0 && !compressor_avail(val))
3703 compress_user_cores = val;
3706 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores,
3707 CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, 0, sizeof(int),
3708 sysctl_compress_user_cores, "I",
3709 "Enable compression of user corefiles ("
3710 __XSTRING(COMPRESS_GZIP) " = gzip, "
3711 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3713 int compress_user_cores_level = 6;
3714 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3715 &compress_user_cores_level, 0,
3716 "Corefile compression level");
3719 * Protect the access to corefilename[] by allproc_lock.
3721 #define corefilename_lock allproc_lock
3723 static char corefilename[MAXPATHLEN] = {"%N.core"};
3724 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3727 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3731 sx_xlock(&corefilename_lock);
3732 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3734 sx_xunlock(&corefilename_lock);
3738 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3739 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3740 "Process corefile name format string");
3743 vnode_close_locked(struct thread *td, struct vnode *vp)
3747 vn_close(vp, FWRITE, td->td_ucred, td);
3751 * If the core format has a %I in it, then we need to check
3752 * for existing corefiles before defining a name.
3753 * To do this we iterate over 0..ncores to find a
3754 * non-existing core file name to use. If all core files are
3755 * already used we choose the oldest one.
3758 corefile_open_last(struct thread *td, char *name, int indexpos,
3759 int indexlen, int ncores, struct vnode **vpp)
3761 struct vnode *oldvp, *nextvp, *vp;
3763 struct nameidata nd;
3764 int error, i, flags, oflags, cmode;
3766 struct timespec lasttime;
3768 nextvp = oldvp = NULL;
3769 cmode = S_IRUSR | S_IWUSR;
3770 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3771 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3773 for (i = 0; i < ncores; i++) {
3774 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3776 ch = name[indexpos + indexlen];
3777 (void)snprintf(name + indexpos, indexlen + 1, "%.*u", indexlen,
3779 name[indexpos + indexlen] = ch;
3781 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3782 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3788 NDFREE(&nd, NDF_ONLY_PNBUF);
3789 if ((flags & O_CREAT) == O_CREAT) {
3794 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
3796 vnode_close_locked(td, vp);
3800 if (oldvp == NULL ||
3801 lasttime.tv_sec > vattr.va_mtime.tv_sec ||
3802 (lasttime.tv_sec == vattr.va_mtime.tv_sec &&
3803 lasttime.tv_nsec >= vattr.va_mtime.tv_nsec)) {
3805 vn_close(oldvp, FWRITE, td->td_ucred, td);
3808 lasttime = vattr.va_mtime;
3810 vnode_close_locked(td, vp);
3814 if (oldvp != NULL) {
3815 if (nextvp == NULL) {
3816 if ((td->td_proc->p_flag & P_SUGID) != 0) {
3818 vn_close(oldvp, FWRITE, td->td_ucred, td);
3821 error = vn_lock(nextvp, LK_EXCLUSIVE);
3823 vn_close(nextvp, FWRITE, td->td_ucred,
3829 vn_close(oldvp, FWRITE, td->td_ucred, td);
3834 vnode_close_locked(td, oldvp);
3843 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3844 * Expand the name described in corefilename, using name, uid, and pid
3845 * and open/create core file.
3846 * corefilename is a printf-like string, with three format specifiers:
3847 * %N name of process ("name")
3848 * %P process id (pid)
3850 * For example, "%N.core" is the default; they can be disabled completely
3851 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3852 * This is controlled by the sysctl variable kern.corefile (see above).
3855 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3856 int compress, int signum, struct vnode **vpp, char **namep)
3859 struct nameidata nd;
3861 char *hostname, *name;
3862 int cmode, error, flags, i, indexpos, indexlen, oflags, ncores;
3865 format = corefilename;
3866 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3870 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3871 sx_slock(&corefilename_lock);
3872 for (i = 0; format[i] != '\0'; i++) {
3873 switch (format[i]) {
3874 case '%': /* Format character */
3876 switch (format[i]) {
3878 sbuf_putc(&sb, '%');
3880 case 'H': /* hostname */
3881 if (hostname == NULL) {
3882 hostname = malloc(MAXHOSTNAMELEN,
3885 getcredhostname(td->td_ucred, hostname,
3887 sbuf_printf(&sb, "%s", hostname);
3889 case 'I': /* autoincrementing index */
3890 if (indexpos != -1) {
3891 sbuf_printf(&sb, "%%I");
3895 indexpos = sbuf_len(&sb);
3896 sbuf_printf(&sb, "%u", ncores - 1);
3897 indexlen = sbuf_len(&sb) - indexpos;
3899 case 'N': /* process name */
3900 sbuf_printf(&sb, "%s", comm);
3902 case 'P': /* process id */
3903 sbuf_printf(&sb, "%u", pid);
3905 case 'S': /* signal number */
3906 sbuf_printf(&sb, "%i", signum);
3908 case 'U': /* user id */
3909 sbuf_printf(&sb, "%u", uid);
3913 "Unknown format character %c in "
3914 "corename `%s'\n", format[i], format);
3919 sbuf_putc(&sb, format[i]);
3923 sx_sunlock(&corefilename_lock);
3924 free(hostname, M_TEMP);
3925 if (compress == COMPRESS_GZIP)
3926 sbuf_printf(&sb, GZIP_SUFFIX);
3927 else if (compress == COMPRESS_ZSTD)
3928 sbuf_printf(&sb, ZSTD_SUFFIX);
3929 if (sbuf_error(&sb) != 0) {
3930 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3931 "long\n", (long)pid, comm, (u_long)uid);
3939 if (indexpos != -1) {
3940 error = corefile_open_last(td, name, indexpos, indexlen, ncores,
3944 "pid %d (%s), uid (%u): Path `%s' failed "
3945 "on initial open test, error = %d\n",
3946 pid, comm, uid, name, error);
3949 cmode = S_IRUSR | S_IWUSR;
3950 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3951 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3952 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3953 if ((td->td_proc->p_flag & P_SUGID) != 0)
3956 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3957 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3961 NDFREE(&nd, NDF_ONLY_PNBUF);
3967 audit_proc_coredump(td, name, error);
3977 * Dump a process' core. The main routine does some
3978 * policy checking, and creates the name of the coredump;
3979 * then it passes on a vnode and a size limit to the process-specific
3980 * coredump routine if there is one; if there _is not_ one, it returns
3981 * ENOSYS; otherwise it returns the error from the process-specific routine.
3985 coredump(struct thread *td)
3987 struct proc *p = td->td_proc;
3988 struct ucred *cred = td->td_ucred;
3992 size_t fullpathsize;
3993 int error, error1, locked;
3994 char *name; /* name of corefile */
3997 char *fullpath, *freepath = NULL;
4000 PROC_LOCK_ASSERT(p, MA_OWNED);
4001 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
4003 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
4004 (p->p_flag2 & P2_NOTRACE) != 0) {
4010 * Note that the bulk of limit checking is done after
4011 * the corefile is created. The exception is if the limit
4012 * for corefiles is 0, in which case we don't bother
4013 * creating the corefile at all. This layout means that
4014 * a corefile is truncated instead of not being created,
4015 * if it is larger than the limit.
4017 limit = (off_t)lim_cur(td, RLIMIT_CORE);
4018 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
4024 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
4025 compress_user_cores, p->p_sig, &vp, &name);
4030 * Don't dump to non-regular files or files with links.
4031 * Do not dump into system files. Effective user must own the corefile.
4033 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
4034 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0 ||
4035 vattr.va_uid != cred->cr_uid) {
4043 /* Postpone other writers, including core dumps of other processes. */
4044 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
4046 lf.l_whence = SEEK_SET;
4049 lf.l_type = F_WRLCK;
4050 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
4054 if (set_core_nodump_flag)
4055 vattr.va_flags = UF_NODUMP;
4056 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
4057 VOP_SETATTR(vp, &vattr, cred);
4060 p->p_acflag |= ACORE;
4063 if (p->p_sysent->sv_coredump != NULL) {
4064 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
4070 lf.l_type = F_UNLCK;
4071 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
4073 vn_rangelock_unlock(vp, rl_cookie);
4076 * Notify the userland helper that a process triggered a core dump.
4077 * This allows the helper to run an automated debugging session.
4079 if (error != 0 || coredump_devctl == 0)
4081 sb = sbuf_new_auto();
4082 if (vn_fullpath_global(p->p_textvp, &fullpath, &freepath) != 0)
4084 sbuf_printf(sb, "comm=\"");
4085 devctl_safe_quote_sb(sb, fullpath);
4086 free(freepath, M_TEMP);
4087 sbuf_printf(sb, "\" core=\"");
4090 * We can't lookup core file vp directly. When we're replacing a core, and
4091 * other random times, we flush the name cache, so it will fail. Instead,
4092 * if the path of the core is relative, add the current dir in front if it.
4094 if (name[0] != '/') {
4095 fullpathsize = MAXPATHLEN;
4096 freepath = malloc(fullpathsize, M_TEMP, M_WAITOK);
4097 if (vn_getcwd(freepath, &fullpath, &fullpathsize) != 0) {
4098 free(freepath, M_TEMP);
4101 devctl_safe_quote_sb(sb, fullpath);
4102 free(freepath, M_TEMP);
4105 devctl_safe_quote_sb(sb, name);
4106 sbuf_printf(sb, "\"");
4107 if (sbuf_finish(sb) == 0)
4108 devctl_notify("kernel", "signal", "coredump", sbuf_data(sb));
4112 error1 = vn_close(vp, FWRITE, cred, td);
4116 audit_proc_coredump(td, name, error);
4123 * Nonexistent system call-- signal process (may want to handle it). Flag
4124 * error in case process won't see signal immediately (blocked or ignored).
4126 #ifndef _SYS_SYSPROTO_H_
4133 nosys(struct thread *td, struct nosys_args *args)
4140 tdsignal(td, SIGSYS);
4142 if (kern_lognosys == 1 || kern_lognosys == 3) {
4143 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
4146 if (kern_lognosys == 2 || kern_lognosys == 3 ||
4147 (p->p_pid == 1 && (kern_lognosys & 3) == 0)) {
4148 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
4155 * Send a SIGIO or SIGURG signal to a process or process group using stored
4156 * credentials rather than those of the current process.
4159 pgsigio(struct sigio **sigiop, int sig, int checkctty)
4162 struct sigio *sigio;
4164 ksiginfo_init(&ksi);
4165 ksi.ksi_signo = sig;
4166 ksi.ksi_code = SI_KERNEL;
4170 if (sigio == NULL) {
4174 if (sigio->sio_pgid > 0) {
4175 PROC_LOCK(sigio->sio_proc);
4176 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
4177 kern_psignal(sigio->sio_proc, sig);
4178 PROC_UNLOCK(sigio->sio_proc);
4179 } else if (sigio->sio_pgid < 0) {
4182 PGRP_LOCK(sigio->sio_pgrp);
4183 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
4185 if (p->p_state == PRS_NORMAL &&
4186 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
4187 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
4188 kern_psignal(p, sig);
4191 PGRP_UNLOCK(sigio->sio_pgrp);
4197 filt_sigattach(struct knote *kn)
4199 struct proc *p = curproc;
4201 kn->kn_ptr.p_proc = p;
4202 kn->kn_flags |= EV_CLEAR; /* automatically set */
4204 knlist_add(p->p_klist, kn, 0);
4210 filt_sigdetach(struct knote *kn)
4212 struct proc *p = kn->kn_ptr.p_proc;
4214 knlist_remove(p->p_klist, kn, 0);
4218 * signal knotes are shared with proc knotes, so we apply a mask to
4219 * the hint in order to differentiate them from process hints. This
4220 * could be avoided by using a signal-specific knote list, but probably
4221 * isn't worth the trouble.
4224 filt_signal(struct knote *kn, long hint)
4227 if (hint & NOTE_SIGNAL) {
4228 hint &= ~NOTE_SIGNAL;
4230 if (kn->kn_id == hint)
4233 return (kn->kn_data != 0);
4241 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
4242 refcount_init(&ps->ps_refcnt, 1);
4243 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
4248 sigacts_free(struct sigacts *ps)
4251 if (refcount_release(&ps->ps_refcnt) == 0)
4253 mtx_destroy(&ps->ps_mtx);
4254 free(ps, M_SUBPROC);
4258 sigacts_hold(struct sigacts *ps)
4261 refcount_acquire(&ps->ps_refcnt);
4266 sigacts_copy(struct sigacts *dest, struct sigacts *src)
4269 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
4270 mtx_lock(&src->ps_mtx);
4271 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
4272 mtx_unlock(&src->ps_mtx);
4276 sigacts_shared(struct sigacts *ps)
4279 return (ps->ps_refcnt > 1);
4283 sig_drop_caught(struct proc *p)
4289 PROC_LOCK_ASSERT(p, MA_OWNED);
4290 mtx_assert(&ps->ps_mtx, MA_OWNED);
4291 SIG_FOREACH(sig, &ps->ps_sigcatch) {
4293 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
4294 sigqueue_delete_proc(p, sig);
4299 sigfastblock_failed(struct thread *td, bool sendsig, bool write)
4304 * Prevent further fetches and SIGSEGVs, allowing thread to
4305 * issue syscalls despite corruption.
4307 sigfastblock_clear(td);
4311 ksiginfo_init_trap(&ksi);
4312 ksi.ksi_signo = SIGSEGV;
4313 ksi.ksi_code = write ? SEGV_ACCERR : SEGV_MAPERR;
4314 ksi.ksi_addr = td->td_sigblock_ptr;
4315 trapsignal(td, &ksi);
4319 sigfastblock_fetch_sig(struct thread *td, bool sendsig, uint32_t *valp)
4323 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0)
4325 if (fueword32((void *)td->td_sigblock_ptr, &res) == -1) {
4326 sigfastblock_failed(td, sendsig, false);
4330 td->td_sigblock_val = res & ~SIGFASTBLOCK_FLAGS;
4335 sigfastblock_resched(struct thread *td, bool resched)
4342 reschedule_signals(p, td->td_sigmask, 0);
4346 td->td_flags |= TDF_ASTPENDING | TDF_NEEDSIGCHK;
4351 sys_sigfastblock(struct thread *td, struct sigfastblock_args *uap)
4360 case SIGFASTBLOCK_SETPTR:
4361 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
4365 if (((uintptr_t)(uap->ptr) & (sizeof(uint32_t) - 1)) != 0) {
4369 td->td_pflags |= TDP_SIGFASTBLOCK;
4370 td->td_sigblock_ptr = uap->ptr;
4373 case SIGFASTBLOCK_UNBLOCK:
4374 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) {
4380 res = casueword32(td->td_sigblock_ptr,
4381 SIGFASTBLOCK_PEND, &oldval, 0);
4384 sigfastblock_failed(td, false, true);
4390 if (oldval != SIGFASTBLOCK_PEND) {
4394 error = thread_check_susp(td, false);
4402 * td_sigblock_val is cleared there, but not on a
4403 * syscall exit. The end effect is that a single
4404 * interruptible sleep, while user sigblock word is
4405 * set, might return EINTR or ERESTART to usermode
4406 * without delivering signal. All further sleeps,
4407 * until userspace clears the word and does
4408 * sigfastblock(UNBLOCK), observe current word and no
4409 * longer get interrupted. It is slight
4410 * non-conformance, with alternative to have read the
4411 * sigblock word on each syscall entry.
4413 td->td_sigblock_val = 0;
4416 * Rely on normal ast mechanism to deliver pending
4417 * signals to current thread. But notify others about
4420 sigfastblock_resched(td, error == 0 && p->p_numthreads != 1);
4424 case SIGFASTBLOCK_UNSETPTR:
4425 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) {
4429 if (!sigfastblock_fetch_sig(td, false, &oldval)) {
4433 if (oldval != 0 && oldval != SIGFASTBLOCK_PEND) {
4437 sigfastblock_clear(td);
4448 sigfastblock_clear(struct thread *td)
4452 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0)
4454 td->td_sigblock_val = 0;
4455 resched = (td->td_pflags & TDP_SIGFASTPENDING) != 0 ||
4457 td->td_pflags &= ~(TDP_SIGFASTBLOCK | TDP_SIGFASTPENDING);
4458 sigfastblock_resched(td, resched);
4462 sigfastblock_fetch(struct thread *td)
4466 (void)sigfastblock_fetch_sig(td, true, &val);
4470 sigfastblock_setpend1(struct thread *td)
4475 if ((td->td_pflags & TDP_SIGFASTPENDING) == 0)
4477 res = fueword32((void *)td->td_sigblock_ptr, &oldval);
4479 sigfastblock_failed(td, true, false);
4483 res = casueword32(td->td_sigblock_ptr, oldval, &oldval,
4484 oldval | SIGFASTBLOCK_PEND);
4486 sigfastblock_failed(td, true, true);
4490 td->td_sigblock_val = oldval & ~SIGFASTBLOCK_FLAGS;
4491 td->td_pflags &= ~TDP_SIGFASTPENDING;
4495 if (thread_check_susp(td, false) != 0)
4501 sigfastblock_setpend(struct thread *td, bool resched)
4505 sigfastblock_setpend1(td);
4509 reschedule_signals(p, fastblock_mask, SIGPROCMASK_FASTBLK);