2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
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9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
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13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
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20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
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33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
42 #include "opt_ktrace.h"
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
51 #include <sys/capsicum.h>
52 #include <sys/compressor.h>
53 #include <sys/condvar.h>
54 #include <sys/event.h>
55 #include <sys/fcntl.h>
56 #include <sys/imgact.h>
57 #include <sys/kernel.h>
59 #include <sys/ktrace.h>
60 #include <sys/limits.h>
62 #include <sys/malloc.h>
63 #include <sys/mutex.h>
64 #include <sys/refcount.h>
65 #include <sys/namei.h>
67 #include <sys/procdesc.h>
68 #include <sys/ptrace.h>
69 #include <sys/posix4.h>
70 #include <sys/pioctl.h>
71 #include <sys/racct.h>
72 #include <sys/resourcevar.h>
75 #include <sys/sleepqueue.h>
79 #include <sys/syscallsubr.h>
80 #include <sys/sysctl.h>
81 #include <sys/sysent.h>
82 #include <sys/syslog.h>
83 #include <sys/sysproto.h>
84 #include <sys/timers.h>
85 #include <sys/unistd.h>
88 #include <vm/vm_extern.h>
93 #include <machine/cpu.h>
95 #include <security/audit/audit.h>
97 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
99 SDT_PROVIDER_DECLARE(proc);
100 SDT_PROBE_DEFINE3(proc, , , signal__send,
101 "struct thread *", "struct proc *", "int");
102 SDT_PROBE_DEFINE2(proc, , , signal__clear,
103 "int", "ksiginfo_t *");
104 SDT_PROBE_DEFINE3(proc, , , signal__discard,
105 "struct thread *", "struct proc *", "int");
107 static int coredump(struct thread *);
108 static int killpg1(struct thread *td, int sig, int pgid, int all,
110 static int issignal(struct thread *td);
111 static int sigprop(int sig);
112 static void tdsigwakeup(struct thread *, int, sig_t, int);
113 static int sig_suspend_threads(struct thread *, struct proc *, int);
114 static int filt_sigattach(struct knote *kn);
115 static void filt_sigdetach(struct knote *kn);
116 static int filt_signal(struct knote *kn, long hint);
117 static struct thread *sigtd(struct proc *p, int sig, int prop);
118 static void sigqueue_start(void);
120 static uma_zone_t ksiginfo_zone = NULL;
121 struct filterops sig_filtops = {
123 .f_attach = filt_sigattach,
124 .f_detach = filt_sigdetach,
125 .f_event = filt_signal,
128 static int kern_logsigexit = 1;
129 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
131 "Log processes quitting on abnormal signals to syslog(3)");
133 static int kern_forcesigexit = 1;
134 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
135 &kern_forcesigexit, 0, "Force trap signal to be handled");
137 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
138 "POSIX real time signal");
140 static int max_pending_per_proc = 128;
141 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
142 &max_pending_per_proc, 0, "Max pending signals per proc");
144 static int preallocate_siginfo = 1024;
145 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
146 &preallocate_siginfo, 0, "Preallocated signal memory size");
148 static int signal_overflow = 0;
149 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
150 &signal_overflow, 0, "Number of signals overflew");
152 static int signal_alloc_fail = 0;
153 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
154 &signal_alloc_fail, 0, "signals failed to be allocated");
156 static int kern_lognosys = 0;
157 SYSCTL_INT(_kern, OID_AUTO, lognosys, CTLFLAG_RWTUN, &kern_lognosys, 0,
158 "Log invalid syscalls");
160 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
163 * Policy -- Can ucred cr1 send SIGIO to process cr2?
164 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
165 * in the right situations.
167 #define CANSIGIO(cr1, cr2) \
168 ((cr1)->cr_uid == 0 || \
169 (cr1)->cr_ruid == (cr2)->cr_ruid || \
170 (cr1)->cr_uid == (cr2)->cr_ruid || \
171 (cr1)->cr_ruid == (cr2)->cr_uid || \
172 (cr1)->cr_uid == (cr2)->cr_uid)
174 static int sugid_coredump;
175 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
176 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
178 static int capmode_coredump;
179 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
180 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
182 static int do_coredump = 1;
183 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
184 &do_coredump, 0, "Enable/Disable coredumps");
186 static int set_core_nodump_flag = 0;
187 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
188 0, "Enable setting the NODUMP flag on coredump files");
190 static int coredump_devctl = 0;
191 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
192 0, "Generate a devctl notification when processes coredump");
195 * Signal properties and actions.
196 * The array below categorizes the signals and their default actions
197 * according to the following properties:
199 #define SIGPROP_KILL 0x01 /* terminates process by default */
200 #define SIGPROP_CORE 0x02 /* ditto and coredumps */
201 #define SIGPROP_STOP 0x04 /* suspend process */
202 #define SIGPROP_TTYSTOP 0x08 /* ditto, from tty */
203 #define SIGPROP_IGNORE 0x10 /* ignore by default */
204 #define SIGPROP_CONT 0x20 /* continue if suspended */
205 #define SIGPROP_CANTMASK 0x40 /* non-maskable, catchable */
207 static int sigproptbl[NSIG] = {
208 [SIGHUP] = SIGPROP_KILL,
209 [SIGINT] = SIGPROP_KILL,
210 [SIGQUIT] = SIGPROP_KILL | SIGPROP_CORE,
211 [SIGILL] = SIGPROP_KILL | SIGPROP_CORE,
212 [SIGTRAP] = SIGPROP_KILL | SIGPROP_CORE,
213 [SIGABRT] = SIGPROP_KILL | SIGPROP_CORE,
214 [SIGEMT] = SIGPROP_KILL | SIGPROP_CORE,
215 [SIGFPE] = SIGPROP_KILL | SIGPROP_CORE,
216 [SIGKILL] = SIGPROP_KILL,
217 [SIGBUS] = SIGPROP_KILL | SIGPROP_CORE,
218 [SIGSEGV] = SIGPROP_KILL | SIGPROP_CORE,
219 [SIGSYS] = SIGPROP_KILL | SIGPROP_CORE,
220 [SIGPIPE] = SIGPROP_KILL,
221 [SIGALRM] = SIGPROP_KILL,
222 [SIGTERM] = SIGPROP_KILL,
223 [SIGURG] = SIGPROP_IGNORE,
224 [SIGSTOP] = SIGPROP_STOP,
225 [SIGTSTP] = SIGPROP_STOP | SIGPROP_TTYSTOP,
226 [SIGCONT] = SIGPROP_IGNORE | SIGPROP_CONT,
227 [SIGCHLD] = SIGPROP_IGNORE,
228 [SIGTTIN] = SIGPROP_STOP | SIGPROP_TTYSTOP,
229 [SIGTTOU] = SIGPROP_STOP | SIGPROP_TTYSTOP,
230 [SIGIO] = SIGPROP_IGNORE,
231 [SIGXCPU] = SIGPROP_KILL,
232 [SIGXFSZ] = SIGPROP_KILL,
233 [SIGVTALRM] = SIGPROP_KILL,
234 [SIGPROF] = SIGPROP_KILL,
235 [SIGWINCH] = SIGPROP_IGNORE,
236 [SIGINFO] = SIGPROP_IGNORE,
237 [SIGUSR1] = SIGPROP_KILL,
238 [SIGUSR2] = SIGPROP_KILL,
241 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
246 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
247 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
248 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
249 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
250 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
251 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
255 ksiginfo_alloc(int wait)
262 if (ksiginfo_zone != NULL)
263 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
268 ksiginfo_free(ksiginfo_t *ksi)
270 uma_zfree(ksiginfo_zone, ksi);
274 ksiginfo_tryfree(ksiginfo_t *ksi)
276 if (!(ksi->ksi_flags & KSI_EXT)) {
277 uma_zfree(ksiginfo_zone, ksi);
284 sigqueue_init(sigqueue_t *list, struct proc *p)
286 SIGEMPTYSET(list->sq_signals);
287 SIGEMPTYSET(list->sq_kill);
288 SIGEMPTYSET(list->sq_ptrace);
289 TAILQ_INIT(&list->sq_list);
291 list->sq_flags = SQ_INIT;
295 * Get a signal's ksiginfo.
297 * 0 - signal not found
298 * others - signal number
301 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
303 struct proc *p = sq->sq_proc;
304 struct ksiginfo *ksi, *next;
307 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
309 if (!SIGISMEMBER(sq->sq_signals, signo))
312 if (SIGISMEMBER(sq->sq_ptrace, signo)) {
314 SIGDELSET(sq->sq_ptrace, signo);
315 si->ksi_flags |= KSI_PTRACE;
317 if (SIGISMEMBER(sq->sq_kill, signo)) {
320 SIGDELSET(sq->sq_kill, signo);
323 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
324 if (ksi->ksi_signo == signo) {
326 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
327 ksi->ksi_sigq = NULL;
328 ksiginfo_copy(ksi, si);
329 if (ksiginfo_tryfree(ksi) && p != NULL)
338 SIGDELSET(sq->sq_signals, signo);
339 si->ksi_signo = signo;
344 sigqueue_take(ksiginfo_t *ksi)
350 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
354 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
355 ksi->ksi_sigq = NULL;
356 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
359 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
360 kp = TAILQ_NEXT(kp, ksi_link)) {
361 if (kp->ksi_signo == ksi->ksi_signo)
364 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) &&
365 !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo))
366 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
370 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
372 struct proc *p = sq->sq_proc;
373 struct ksiginfo *ksi;
376 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
379 * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path
382 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
383 SIGADDSET(sq->sq_kill, signo);
387 /* directly insert the ksi, don't copy it */
388 if (si->ksi_flags & KSI_INS) {
389 if (si->ksi_flags & KSI_HEAD)
390 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
392 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
397 if (__predict_false(ksiginfo_zone == NULL)) {
398 SIGADDSET(sq->sq_kill, signo);
402 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
405 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
411 ksiginfo_copy(si, ksi);
412 ksi->ksi_signo = signo;
413 if (si->ksi_flags & KSI_HEAD)
414 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
416 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
421 if ((si->ksi_flags & KSI_PTRACE) != 0) {
422 SIGADDSET(sq->sq_ptrace, signo);
425 } else if ((si->ksi_flags & KSI_TRAP) != 0 ||
426 (si->ksi_flags & KSI_SIGQ) == 0) {
427 SIGADDSET(sq->sq_kill, signo);
435 SIGADDSET(sq->sq_signals, signo);
440 sigqueue_flush(sigqueue_t *sq)
442 struct proc *p = sq->sq_proc;
445 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
448 PROC_LOCK_ASSERT(p, MA_OWNED);
450 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
451 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
452 ksi->ksi_sigq = NULL;
453 if (ksiginfo_tryfree(ksi) && p != NULL)
457 SIGEMPTYSET(sq->sq_signals);
458 SIGEMPTYSET(sq->sq_kill);
459 SIGEMPTYSET(sq->sq_ptrace);
463 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
466 struct proc *p1, *p2;
467 ksiginfo_t *ksi, *next;
469 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
470 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
473 /* Move siginfo to target list */
474 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
475 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
476 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
479 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
486 /* Move pending bits to target list */
488 SIGSETAND(tmp, *set);
489 SIGSETOR(dst->sq_kill, tmp);
490 SIGSETNAND(src->sq_kill, tmp);
492 tmp = src->sq_ptrace;
493 SIGSETAND(tmp, *set);
494 SIGSETOR(dst->sq_ptrace, tmp);
495 SIGSETNAND(src->sq_ptrace, tmp);
497 tmp = src->sq_signals;
498 SIGSETAND(tmp, *set);
499 SIGSETOR(dst->sq_signals, tmp);
500 SIGSETNAND(src->sq_signals, tmp);
505 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
510 SIGADDSET(set, signo);
511 sigqueue_move_set(src, dst, &set);
516 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
518 struct proc *p = sq->sq_proc;
519 ksiginfo_t *ksi, *next;
521 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
523 /* Remove siginfo queue */
524 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
525 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
526 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
527 ksi->ksi_sigq = NULL;
528 if (ksiginfo_tryfree(ksi) && p != NULL)
532 SIGSETNAND(sq->sq_kill, *set);
533 SIGSETNAND(sq->sq_ptrace, *set);
534 SIGSETNAND(sq->sq_signals, *set);
538 sigqueue_delete(sigqueue_t *sq, int signo)
543 SIGADDSET(set, signo);
544 sigqueue_delete_set(sq, &set);
547 /* Remove a set of signals for a process */
549 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
554 PROC_LOCK_ASSERT(p, MA_OWNED);
556 sigqueue_init(&worklist, NULL);
557 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
559 FOREACH_THREAD_IN_PROC(p, td0)
560 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
562 sigqueue_flush(&worklist);
566 sigqueue_delete_proc(struct proc *p, int signo)
571 SIGADDSET(set, signo);
572 sigqueue_delete_set_proc(p, &set);
576 sigqueue_delete_stopmask_proc(struct proc *p)
581 SIGADDSET(set, SIGSTOP);
582 SIGADDSET(set, SIGTSTP);
583 SIGADDSET(set, SIGTTIN);
584 SIGADDSET(set, SIGTTOU);
585 sigqueue_delete_set_proc(p, &set);
589 * Determine signal that should be delivered to thread td, the current
590 * thread, 0 if none. If there is a pending stop signal with default
591 * action, the process stops in issignal().
594 cursig(struct thread *td)
596 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
597 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
598 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
599 return (SIGPENDING(td) ? issignal(td) : 0);
603 * Arrange for ast() to handle unmasked pending signals on return to user
604 * mode. This must be called whenever a signal is added to td_sigqueue or
605 * unmasked in td_sigmask.
608 signotify(struct thread *td)
611 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
613 if (SIGPENDING(td)) {
615 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
621 * Returns 1 (true) if altstack is configured for the thread, and the
622 * passed stack bottom address falls into the altstack range. Handles
623 * the 43 compat special case where the alt stack size is zero.
626 sigonstack(size_t sp)
631 if ((td->td_pflags & TDP_ALTSTACK) == 0)
633 #if defined(COMPAT_43)
634 if (SV_PROC_FLAG(td->td_proc, SV_AOUT) && td->td_sigstk.ss_size == 0)
635 return ((td->td_sigstk.ss_flags & SS_ONSTACK) != 0);
637 return (sp >= (size_t)td->td_sigstk.ss_sp &&
638 sp < td->td_sigstk.ss_size + (size_t)td->td_sigstk.ss_sp);
645 if (sig > 0 && sig < nitems(sigproptbl))
646 return (sigproptbl[sig]);
651 sig_ffs(sigset_t *set)
655 for (i = 0; i < _SIG_WORDS; i++)
657 return (ffs(set->__bits[i]) + (i * 32));
662 sigact_flag_test(const struct sigaction *act, int flag)
666 * SA_SIGINFO is reset when signal disposition is set to
667 * ignore or default. Other flags are kept according to user
670 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
671 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
672 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
682 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
683 struct sigaction *oact, int flags)
686 struct proc *p = td->td_proc;
688 if (!_SIG_VALID(sig))
690 if (act != NULL && act->sa_handler != SIG_DFL &&
691 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
692 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
693 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
698 mtx_lock(&ps->ps_mtx);
700 memset(oact, 0, sizeof(*oact));
701 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
702 if (SIGISMEMBER(ps->ps_sigonstack, sig))
703 oact->sa_flags |= SA_ONSTACK;
704 if (!SIGISMEMBER(ps->ps_sigintr, sig))
705 oact->sa_flags |= SA_RESTART;
706 if (SIGISMEMBER(ps->ps_sigreset, sig))
707 oact->sa_flags |= SA_RESETHAND;
708 if (SIGISMEMBER(ps->ps_signodefer, sig))
709 oact->sa_flags |= SA_NODEFER;
710 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
711 oact->sa_flags |= SA_SIGINFO;
713 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
715 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
716 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
717 oact->sa_flags |= SA_NOCLDSTOP;
718 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
719 oact->sa_flags |= SA_NOCLDWAIT;
722 if ((sig == SIGKILL || sig == SIGSTOP) &&
723 act->sa_handler != SIG_DFL) {
724 mtx_unlock(&ps->ps_mtx);
730 * Change setting atomically.
733 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
734 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
735 if (sigact_flag_test(act, SA_SIGINFO)) {
736 ps->ps_sigact[_SIG_IDX(sig)] =
737 (__sighandler_t *)act->sa_sigaction;
738 SIGADDSET(ps->ps_siginfo, sig);
740 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
741 SIGDELSET(ps->ps_siginfo, sig);
743 if (!sigact_flag_test(act, SA_RESTART))
744 SIGADDSET(ps->ps_sigintr, sig);
746 SIGDELSET(ps->ps_sigintr, sig);
747 if (sigact_flag_test(act, SA_ONSTACK))
748 SIGADDSET(ps->ps_sigonstack, sig);
750 SIGDELSET(ps->ps_sigonstack, sig);
751 if (sigact_flag_test(act, SA_RESETHAND))
752 SIGADDSET(ps->ps_sigreset, sig);
754 SIGDELSET(ps->ps_sigreset, sig);
755 if (sigact_flag_test(act, SA_NODEFER))
756 SIGADDSET(ps->ps_signodefer, sig);
758 SIGDELSET(ps->ps_signodefer, sig);
759 if (sig == SIGCHLD) {
760 if (act->sa_flags & SA_NOCLDSTOP)
761 ps->ps_flag |= PS_NOCLDSTOP;
763 ps->ps_flag &= ~PS_NOCLDSTOP;
764 if (act->sa_flags & SA_NOCLDWAIT) {
766 * Paranoia: since SA_NOCLDWAIT is implemented
767 * by reparenting the dying child to PID 1 (and
768 * trust it to reap the zombie), PID 1 itself
769 * is forbidden to set SA_NOCLDWAIT.
772 ps->ps_flag &= ~PS_NOCLDWAIT;
774 ps->ps_flag |= PS_NOCLDWAIT;
776 ps->ps_flag &= ~PS_NOCLDWAIT;
777 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
778 ps->ps_flag |= PS_CLDSIGIGN;
780 ps->ps_flag &= ~PS_CLDSIGIGN;
783 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
784 * and for signals set to SIG_DFL where the default is to
785 * ignore. However, don't put SIGCONT in ps_sigignore, as we
786 * have to restart the process.
788 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
789 (sigprop(sig) & SIGPROP_IGNORE &&
790 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
791 /* never to be seen again */
792 sigqueue_delete_proc(p, sig);
794 /* easier in psignal */
795 SIGADDSET(ps->ps_sigignore, sig);
796 SIGDELSET(ps->ps_sigcatch, sig);
798 SIGDELSET(ps->ps_sigignore, sig);
799 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
800 SIGDELSET(ps->ps_sigcatch, sig);
802 SIGADDSET(ps->ps_sigcatch, sig);
804 #ifdef COMPAT_FREEBSD4
805 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
806 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
807 (flags & KSA_FREEBSD4) == 0)
808 SIGDELSET(ps->ps_freebsd4, sig);
810 SIGADDSET(ps->ps_freebsd4, sig);
813 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
814 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
815 (flags & KSA_OSIGSET) == 0)
816 SIGDELSET(ps->ps_osigset, sig);
818 SIGADDSET(ps->ps_osigset, sig);
821 mtx_unlock(&ps->ps_mtx);
826 #ifndef _SYS_SYSPROTO_H_
827 struct sigaction_args {
829 struct sigaction *act;
830 struct sigaction *oact;
834 sys_sigaction(struct thread *td, struct sigaction_args *uap)
836 struct sigaction act, oact;
837 struct sigaction *actp, *oactp;
840 actp = (uap->act != NULL) ? &act : NULL;
841 oactp = (uap->oact != NULL) ? &oact : NULL;
843 error = copyin(uap->act, actp, sizeof(act));
847 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
849 error = copyout(oactp, uap->oact, sizeof(oact));
853 #ifdef COMPAT_FREEBSD4
854 #ifndef _SYS_SYSPROTO_H_
855 struct freebsd4_sigaction_args {
857 struct sigaction *act;
858 struct sigaction *oact;
862 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
864 struct sigaction act, oact;
865 struct sigaction *actp, *oactp;
869 actp = (uap->act != NULL) ? &act : NULL;
870 oactp = (uap->oact != NULL) ? &oact : NULL;
872 error = copyin(uap->act, actp, sizeof(act));
876 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
878 error = copyout(oactp, uap->oact, sizeof(oact));
881 #endif /* COMAPT_FREEBSD4 */
883 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
884 #ifndef _SYS_SYSPROTO_H_
885 struct osigaction_args {
887 struct osigaction *nsa;
888 struct osigaction *osa;
892 osigaction(struct thread *td, struct osigaction_args *uap)
894 struct osigaction sa;
895 struct sigaction nsa, osa;
896 struct sigaction *nsap, *osap;
899 if (uap->signum <= 0 || uap->signum >= ONSIG)
902 nsap = (uap->nsa != NULL) ? &nsa : NULL;
903 osap = (uap->osa != NULL) ? &osa : NULL;
906 error = copyin(uap->nsa, &sa, sizeof(sa));
909 nsap->sa_handler = sa.sa_handler;
910 nsap->sa_flags = sa.sa_flags;
911 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
913 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
914 if (osap && !error) {
915 sa.sa_handler = osap->sa_handler;
916 sa.sa_flags = osap->sa_flags;
917 SIG2OSIG(osap->sa_mask, sa.sa_mask);
918 error = copyout(&sa, uap->osa, sizeof(sa));
923 #if !defined(__i386__)
924 /* Avoid replicating the same stub everywhere */
926 osigreturn(struct thread *td, struct osigreturn_args *uap)
929 return (nosys(td, (struct nosys_args *)uap));
932 #endif /* COMPAT_43 */
935 * Initialize signal state for process 0;
936 * set to ignore signals that are ignored by default.
939 siginit(struct proc *p)
946 mtx_lock(&ps->ps_mtx);
947 for (i = 1; i <= NSIG; i++) {
948 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
949 SIGADDSET(ps->ps_sigignore, i);
952 mtx_unlock(&ps->ps_mtx);
957 * Reset specified signal to the default disposition.
960 sigdflt(struct sigacts *ps, int sig)
963 mtx_assert(&ps->ps_mtx, MA_OWNED);
964 SIGDELSET(ps->ps_sigcatch, sig);
965 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
966 SIGADDSET(ps->ps_sigignore, sig);
967 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
968 SIGDELSET(ps->ps_siginfo, sig);
972 * Reset signals for an exec of the specified process.
975 execsigs(struct proc *p)
983 * Reset caught signals. Held signals remain held
984 * through td_sigmask (unless they were caught,
985 * and are now ignored by default).
987 PROC_LOCK_ASSERT(p, MA_OWNED);
989 mtx_lock(&ps->ps_mtx);
993 * As CloudABI processes cannot modify signal handlers, fully
994 * reset all signals to their default behavior. Do ignore
995 * SIGPIPE, as it would otherwise be impossible to recover from
996 * writes to broken pipes and sockets.
998 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
999 osigignore = ps->ps_sigignore;
1000 while (SIGNOTEMPTY(osigignore)) {
1001 sig = sig_ffs(&osigignore);
1002 SIGDELSET(osigignore, sig);
1006 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1010 * Reset stack state to the user stack.
1011 * Clear set of signals caught on the signal stack.
1014 MPASS(td->td_proc == p);
1015 td->td_sigstk.ss_flags = SS_DISABLE;
1016 td->td_sigstk.ss_size = 0;
1017 td->td_sigstk.ss_sp = 0;
1018 td->td_pflags &= ~TDP_ALTSTACK;
1020 * Reset no zombies if child dies flag as Solaris does.
1022 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1023 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1024 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1025 mtx_unlock(&ps->ps_mtx);
1029 * kern_sigprocmask()
1031 * Manipulate signal mask.
1034 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1037 sigset_t new_block, oset1;
1042 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1043 PROC_LOCK_ASSERT(p, MA_OWNED);
1046 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1047 ? MA_OWNED : MA_NOTOWNED);
1049 *oset = td->td_sigmask;
1056 oset1 = td->td_sigmask;
1057 SIGSETOR(td->td_sigmask, *set);
1058 new_block = td->td_sigmask;
1059 SIGSETNAND(new_block, oset1);
1062 SIGSETNAND(td->td_sigmask, *set);
1067 oset1 = td->td_sigmask;
1068 if (flags & SIGPROCMASK_OLD)
1069 SIGSETLO(td->td_sigmask, *set);
1071 td->td_sigmask = *set;
1072 new_block = td->td_sigmask;
1073 SIGSETNAND(new_block, oset1);
1082 * The new_block set contains signals that were not previously
1083 * blocked, but are blocked now.
1085 * In case we block any signal that was not previously blocked
1086 * for td, and process has the signal pending, try to schedule
1087 * signal delivery to some thread that does not block the
1088 * signal, possibly waking it up.
1090 if (p->p_numthreads != 1)
1091 reschedule_signals(p, new_block, flags);
1095 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1100 #ifndef _SYS_SYSPROTO_H_
1101 struct sigprocmask_args {
1103 const sigset_t *set;
1108 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1111 sigset_t *setp, *osetp;
1114 setp = (uap->set != NULL) ? &set : NULL;
1115 osetp = (uap->oset != NULL) ? &oset : NULL;
1117 error = copyin(uap->set, setp, sizeof(set));
1121 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1122 if (osetp && !error) {
1123 error = copyout(osetp, uap->oset, sizeof(oset));
1128 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1129 #ifndef _SYS_SYSPROTO_H_
1130 struct osigprocmask_args {
1136 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1141 OSIG2SIG(uap->mask, set);
1142 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1143 SIG2OSIG(oset, td->td_retval[0]);
1146 #endif /* COMPAT_43 */
1149 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1155 error = copyin(uap->set, &set, sizeof(set));
1157 td->td_retval[0] = error;
1161 error = kern_sigtimedwait(td, set, &ksi, NULL);
1163 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1165 if (error == ERESTART)
1167 td->td_retval[0] = error;
1171 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1172 td->td_retval[0] = error;
1177 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1180 struct timespec *timeout;
1186 error = copyin(uap->timeout, &ts, sizeof(ts));
1194 error = copyin(uap->set, &set, sizeof(set));
1198 error = kern_sigtimedwait(td, set, &ksi, timeout);
1203 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1206 td->td_retval[0] = ksi.ksi_signo;
1211 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1217 error = copyin(uap->set, &set, sizeof(set));
1221 error = kern_sigtimedwait(td, set, &ksi, NULL);
1226 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1229 td->td_retval[0] = ksi.ksi_signo;
1234 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1238 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1242 thr->td_si.si_signo = 0;
1247 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1248 struct timespec *timeout)
1251 sigset_t saved_mask, new_block;
1253 int error, sig, timo, timevalid = 0;
1254 struct timespec rts, ets, ts;
1264 if (timeout != NULL) {
1265 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1267 getnanouptime(&rts);
1268 timespecadd(&rts, timeout, &ets);
1272 /* Some signals can not be waited for. */
1273 SIG_CANTMASK(waitset);
1276 saved_mask = td->td_sigmask;
1277 SIGSETNAND(td->td_sigmask, waitset);
1279 mtx_lock(&ps->ps_mtx);
1281 mtx_unlock(&ps->ps_mtx);
1282 KASSERT(sig >= 0, ("sig %d", sig));
1283 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1284 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1285 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1295 * POSIX says this must be checked after looking for pending
1298 if (timeout != NULL) {
1303 getnanouptime(&rts);
1304 if (timespeccmp(&rts, &ets, >=)) {
1308 timespecsub(&ets, &rts, &ts);
1309 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1320 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1322 if (timeout != NULL) {
1323 if (error == ERESTART) {
1324 /* Timeout can not be restarted. */
1326 } else if (error == EAGAIN) {
1327 /* We will calculate timeout by ourself. */
1333 * If PTRACE_SCE or PTRACE_SCX were set after
1334 * userspace entered the syscall, return spurious
1335 * EINTR after wait was done. Only do this as last
1336 * resort after rechecking for possible queued signals
1337 * and expired timeouts.
1339 if (error == 0 && (p->p_ptevents & PTRACE_SYSCALL) != 0)
1343 new_block = saved_mask;
1344 SIGSETNAND(new_block, td->td_sigmask);
1345 td->td_sigmask = saved_mask;
1347 * Fewer signals can be delivered to us, reschedule signal
1350 if (p->p_numthreads != 1)
1351 reschedule_signals(p, new_block, 0);
1354 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1356 if (ksi->ksi_code == SI_TIMER)
1357 itimer_accept(p, ksi->ksi_timerid, ksi);
1360 if (KTRPOINT(td, KTR_PSIG)) {
1363 mtx_lock(&ps->ps_mtx);
1364 action = ps->ps_sigact[_SIG_IDX(sig)];
1365 mtx_unlock(&ps->ps_mtx);
1366 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1369 if (sig == SIGKILL) {
1370 proc_td_siginfo_capture(td, &ksi->ksi_info);
1378 #ifndef _SYS_SYSPROTO_H_
1379 struct sigpending_args {
1384 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1386 struct proc *p = td->td_proc;
1390 pending = p->p_sigqueue.sq_signals;
1391 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1393 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1396 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1397 #ifndef _SYS_SYSPROTO_H_
1398 struct osigpending_args {
1403 osigpending(struct thread *td, struct osigpending_args *uap)
1405 struct proc *p = td->td_proc;
1409 pending = p->p_sigqueue.sq_signals;
1410 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1412 SIG2OSIG(pending, td->td_retval[0]);
1415 #endif /* COMPAT_43 */
1417 #if defined(COMPAT_43)
1419 * Generalized interface signal handler, 4.3-compatible.
1421 #ifndef _SYS_SYSPROTO_H_
1422 struct osigvec_args {
1430 osigvec(struct thread *td, struct osigvec_args *uap)
1433 struct sigaction nsa, osa;
1434 struct sigaction *nsap, *osap;
1437 if (uap->signum <= 0 || uap->signum >= ONSIG)
1439 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1440 osap = (uap->osv != NULL) ? &osa : NULL;
1442 error = copyin(uap->nsv, &vec, sizeof(vec));
1445 nsap->sa_handler = vec.sv_handler;
1446 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1447 nsap->sa_flags = vec.sv_flags;
1448 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1450 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1451 if (osap && !error) {
1452 vec.sv_handler = osap->sa_handler;
1453 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1454 vec.sv_flags = osap->sa_flags;
1455 vec.sv_flags &= ~SA_NOCLDWAIT;
1456 vec.sv_flags ^= SA_RESTART;
1457 error = copyout(&vec, uap->osv, sizeof(vec));
1462 #ifndef _SYS_SYSPROTO_H_
1463 struct osigblock_args {
1468 osigblock(struct thread *td, struct osigblock_args *uap)
1472 OSIG2SIG(uap->mask, set);
1473 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1474 SIG2OSIG(oset, td->td_retval[0]);
1478 #ifndef _SYS_SYSPROTO_H_
1479 struct osigsetmask_args {
1484 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1488 OSIG2SIG(uap->mask, set);
1489 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1490 SIG2OSIG(oset, td->td_retval[0]);
1493 #endif /* COMPAT_43 */
1496 * Suspend calling thread until signal, providing mask to be set in the
1499 #ifndef _SYS_SYSPROTO_H_
1500 struct sigsuspend_args {
1501 const sigset_t *sigmask;
1506 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1511 error = copyin(uap->sigmask, &mask, sizeof(mask));
1514 return (kern_sigsuspend(td, mask));
1518 kern_sigsuspend(struct thread *td, sigset_t mask)
1520 struct proc *p = td->td_proc;
1524 * When returning from sigsuspend, we want
1525 * the old mask to be restored after the
1526 * signal handler has finished. Thus, we
1527 * save it here and mark the sigacts structure
1531 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1532 SIGPROCMASK_PROC_LOCKED);
1533 td->td_pflags |= TDP_OLDMASK;
1536 * Process signals now. Otherwise, we can get spurious wakeup
1537 * due to signal entered process queue, but delivered to other
1538 * thread. But sigsuspend should return only on signal
1541 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1542 for (has_sig = 0; !has_sig;) {
1543 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1546 thread_suspend_check(0);
1547 mtx_lock(&p->p_sigacts->ps_mtx);
1548 while ((sig = cursig(td)) != 0) {
1549 KASSERT(sig >= 0, ("sig %d", sig));
1550 has_sig += postsig(sig);
1552 mtx_unlock(&p->p_sigacts->ps_mtx);
1555 * If PTRACE_SCE or PTRACE_SCX were set after
1556 * userspace entered the syscall, return spurious
1559 if ((p->p_ptevents & PTRACE_SYSCALL) != 0)
1563 td->td_errno = EINTR;
1564 td->td_pflags |= TDP_NERRNO;
1565 return (EJUSTRETURN);
1568 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1570 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1571 * convention: libc stub passes mask, not pointer, to save a copyin.
1573 #ifndef _SYS_SYSPROTO_H_
1574 struct osigsuspend_args {
1580 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1584 OSIG2SIG(uap->mask, mask);
1585 return (kern_sigsuspend(td, mask));
1587 #endif /* COMPAT_43 */
1589 #if defined(COMPAT_43)
1590 #ifndef _SYS_SYSPROTO_H_
1591 struct osigstack_args {
1592 struct sigstack *nss;
1593 struct sigstack *oss;
1598 osigstack(struct thread *td, struct osigstack_args *uap)
1600 struct sigstack nss, oss;
1603 if (uap->nss != NULL) {
1604 error = copyin(uap->nss, &nss, sizeof(nss));
1608 oss.ss_sp = td->td_sigstk.ss_sp;
1609 oss.ss_onstack = sigonstack(cpu_getstack(td));
1610 if (uap->nss != NULL) {
1611 td->td_sigstk.ss_sp = nss.ss_sp;
1612 td->td_sigstk.ss_size = 0;
1613 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1614 td->td_pflags |= TDP_ALTSTACK;
1616 if (uap->oss != NULL)
1617 error = copyout(&oss, uap->oss, sizeof(oss));
1621 #endif /* COMPAT_43 */
1623 #ifndef _SYS_SYSPROTO_H_
1624 struct sigaltstack_args {
1631 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1636 if (uap->ss != NULL) {
1637 error = copyin(uap->ss, &ss, sizeof(ss));
1641 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1642 (uap->oss != NULL) ? &oss : NULL);
1645 if (uap->oss != NULL)
1646 error = copyout(&oss, uap->oss, sizeof(stack_t));
1651 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1653 struct proc *p = td->td_proc;
1656 oonstack = sigonstack(cpu_getstack(td));
1659 *oss = td->td_sigstk;
1660 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1661 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1667 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1669 if (!(ss->ss_flags & SS_DISABLE)) {
1670 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1673 td->td_sigstk = *ss;
1674 td->td_pflags |= TDP_ALTSTACK;
1676 td->td_pflags &= ~TDP_ALTSTACK;
1682 struct killpg1_ctx {
1692 killpg1_sendsig(struct proc *p, bool notself, struct killpg1_ctx *arg)
1696 if (p->p_pid <= 1 || (p->p_flag & P_SYSTEM) != 0 ||
1697 (notself && p == arg->td->td_proc) || p->p_state == PRS_NEW)
1700 err = p_cansignal(arg->td, p, arg->sig);
1701 if (err == 0 && arg->sig != 0)
1702 pksignal(p, arg->sig, arg->ksi);
1708 else if (arg->ret == 0 && err != ESRCH && err != EPERM)
1713 * Common code for kill process group/broadcast kill.
1714 * cp is calling process.
1717 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1721 struct killpg1_ctx arg;
1733 sx_slock(&allproc_lock);
1734 FOREACH_PROC_IN_SYSTEM(p) {
1735 killpg1_sendsig(p, true, &arg);
1737 sx_sunlock(&allproc_lock);
1739 sx_slock(&proctree_lock);
1742 * zero pgid means send to my process group.
1744 pgrp = td->td_proc->p_pgrp;
1747 pgrp = pgfind(pgid);
1749 sx_sunlock(&proctree_lock);
1753 sx_sunlock(&proctree_lock);
1754 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1755 killpg1_sendsig(p, false, &arg);
1759 MPASS(arg.ret != 0 || arg.found || !arg.sent);
1760 if (arg.ret == 0 && !arg.sent)
1761 arg.ret = arg.found ? EPERM : ESRCH;
1765 #ifndef _SYS_SYSPROTO_H_
1773 sys_kill(struct thread *td, struct kill_args *uap)
1780 * A process in capability mode can send signals only to himself.
1781 * The main rationale behind this is that abort(3) is implemented as
1782 * kill(getpid(), SIGABRT).
1784 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1787 AUDIT_ARG_SIGNUM(uap->signum);
1788 AUDIT_ARG_PID(uap->pid);
1789 if ((u_int)uap->signum > _SIG_MAXSIG)
1792 ksiginfo_init(&ksi);
1793 ksi.ksi_signo = uap->signum;
1794 ksi.ksi_code = SI_USER;
1795 ksi.ksi_pid = td->td_proc->p_pid;
1796 ksi.ksi_uid = td->td_ucred->cr_ruid;
1799 /* kill single process */
1800 if ((p = pfind_any(uap->pid)) == NULL)
1802 AUDIT_ARG_PROCESS(p);
1803 error = p_cansignal(td, p, uap->signum);
1804 if (error == 0 && uap->signum)
1805 pksignal(p, uap->signum, &ksi);
1810 case -1: /* broadcast signal */
1811 return (killpg1(td, uap->signum, 0, 1, &ksi));
1812 case 0: /* signal own process group */
1813 return (killpg1(td, uap->signum, 0, 0, &ksi));
1814 default: /* negative explicit process group */
1815 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1821 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1826 AUDIT_ARG_SIGNUM(uap->signum);
1827 AUDIT_ARG_FD(uap->fd);
1828 if ((u_int)uap->signum > _SIG_MAXSIG)
1831 error = procdesc_find(td, uap->fd, &cap_pdkill_rights, &p);
1834 AUDIT_ARG_PROCESS(p);
1835 error = p_cansignal(td, p, uap->signum);
1836 if (error == 0 && uap->signum)
1837 kern_psignal(p, uap->signum);
1842 #if defined(COMPAT_43)
1843 #ifndef _SYS_SYSPROTO_H_
1844 struct okillpg_args {
1851 okillpg(struct thread *td, struct okillpg_args *uap)
1855 AUDIT_ARG_SIGNUM(uap->signum);
1856 AUDIT_ARG_PID(uap->pgid);
1857 if ((u_int)uap->signum > _SIG_MAXSIG)
1860 ksiginfo_init(&ksi);
1861 ksi.ksi_signo = uap->signum;
1862 ksi.ksi_code = SI_USER;
1863 ksi.ksi_pid = td->td_proc->p_pid;
1864 ksi.ksi_uid = td->td_ucred->cr_ruid;
1865 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1867 #endif /* COMPAT_43 */
1869 #ifndef _SYS_SYSPROTO_H_
1870 struct sigqueue_args {
1873 /* union sigval */ void *value;
1877 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1881 sv.sival_ptr = uap->value;
1883 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1887 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1893 if ((u_int)signum > _SIG_MAXSIG)
1897 * Specification says sigqueue can only send signal to
1903 if ((p = pfind_any(pid)) == NULL)
1905 error = p_cansignal(td, p, signum);
1906 if (error == 0 && signum != 0) {
1907 ksiginfo_init(&ksi);
1908 ksi.ksi_flags = KSI_SIGQ;
1909 ksi.ksi_signo = signum;
1910 ksi.ksi_code = SI_QUEUE;
1911 ksi.ksi_pid = td->td_proc->p_pid;
1912 ksi.ksi_uid = td->td_ucred->cr_ruid;
1913 ksi.ksi_value = *value;
1914 error = pksignal(p, ksi.ksi_signo, &ksi);
1921 * Send a signal to a process group.
1924 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1929 sx_slock(&proctree_lock);
1930 pgrp = pgfind(pgid);
1931 sx_sunlock(&proctree_lock);
1933 pgsignal(pgrp, sig, 0, ksi);
1940 * Send a signal to a process group. If checktty is 1,
1941 * limit to members which have a controlling terminal.
1944 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1949 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1950 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1952 if (p->p_state == PRS_NORMAL &&
1953 (checkctty == 0 || p->p_flag & P_CONTROLT))
1954 pksignal(p, sig, ksi);
1962 * Recalculate the signal mask and reset the signal disposition after
1963 * usermode frame for delivery is formed. Should be called after
1964 * mach-specific routine, because sysent->sv_sendsig() needs correct
1965 * ps_siginfo and signal mask.
1968 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1972 mtx_assert(&ps->ps_mtx, MA_OWNED);
1973 td->td_ru.ru_nsignals++;
1974 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1975 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1976 SIGADDSET(mask, sig);
1977 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1978 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1979 if (SIGISMEMBER(ps->ps_sigreset, sig))
1985 * Send a signal caused by a trap to the current thread. If it will be
1986 * caught immediately, deliver it with correct code. Otherwise, post it
1990 trapsignal(struct thread *td, ksiginfo_t *ksi)
1998 sig = ksi->ksi_signo;
1999 code = ksi->ksi_code;
2000 KASSERT(_SIG_VALID(sig), ("invalid signal"));
2004 mtx_lock(&ps->ps_mtx);
2005 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
2006 !SIGISMEMBER(td->td_sigmask, sig)) {
2008 if (KTRPOINT(curthread, KTR_PSIG))
2009 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
2010 &td->td_sigmask, code);
2012 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
2013 ksi, &td->td_sigmask);
2014 postsig_done(sig, td, ps);
2015 mtx_unlock(&ps->ps_mtx);
2018 * Avoid a possible infinite loop if the thread
2019 * masking the signal or process is ignoring the
2022 if (kern_forcesigexit &&
2023 (SIGISMEMBER(td->td_sigmask, sig) ||
2024 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
2025 SIGDELSET(td->td_sigmask, sig);
2026 SIGDELSET(ps->ps_sigcatch, sig);
2027 SIGDELSET(ps->ps_sigignore, sig);
2028 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2030 mtx_unlock(&ps->ps_mtx);
2031 p->p_sig = sig; /* XXX to verify code */
2032 tdsendsignal(p, td, sig, ksi);
2037 static struct thread *
2038 sigtd(struct proc *p, int sig, int prop)
2040 struct thread *td, *signal_td;
2042 PROC_LOCK_ASSERT(p, MA_OWNED);
2045 * Check if current thread can handle the signal without
2046 * switching context to another thread.
2048 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
2051 FOREACH_THREAD_IN_PROC(p, td) {
2052 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2057 if (signal_td == NULL)
2058 signal_td = FIRST_THREAD_IN_PROC(p);
2063 * Send the signal to the process. If the signal has an action, the action
2064 * is usually performed by the target process rather than the caller; we add
2065 * the signal to the set of pending signals for the process.
2068 * o When a stop signal is sent to a sleeping process that takes the
2069 * default action, the process is stopped without awakening it.
2070 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2071 * regardless of the signal action (eg, blocked or ignored).
2073 * Other ignored signals are discarded immediately.
2075 * NB: This function may be entered from the debugger via the "kill" DDB
2076 * command. There is little that can be done to mitigate the possibly messy
2077 * side effects of this unwise possibility.
2080 kern_psignal(struct proc *p, int sig)
2084 ksiginfo_init(&ksi);
2085 ksi.ksi_signo = sig;
2086 ksi.ksi_code = SI_KERNEL;
2087 (void) tdsendsignal(p, NULL, sig, &ksi);
2091 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2094 return (tdsendsignal(p, NULL, sig, ksi));
2097 /* Utility function for finding a thread to send signal event to. */
2099 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2103 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2104 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2116 tdsignal(struct thread *td, int sig)
2120 ksiginfo_init(&ksi);
2121 ksi.ksi_signo = sig;
2122 ksi.ksi_code = SI_KERNEL;
2123 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2127 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2130 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2134 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2137 sigqueue_t *sigqueue;
2144 MPASS(td == NULL || p == td->td_proc);
2145 PROC_LOCK_ASSERT(p, MA_OWNED);
2147 if (!_SIG_VALID(sig))
2148 panic("%s(): invalid signal %d", __func__, sig);
2150 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2153 * IEEE Std 1003.1-2001: return success when killing a zombie.
2155 if (p->p_state == PRS_ZOMBIE) {
2156 if (ksi && (ksi->ksi_flags & KSI_INS))
2157 ksiginfo_tryfree(ksi);
2162 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2163 prop = sigprop(sig);
2166 td = sigtd(p, sig, prop);
2167 sigqueue = &p->p_sigqueue;
2169 sigqueue = &td->td_sigqueue;
2171 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2174 * If the signal is being ignored,
2175 * then we forget about it immediately.
2176 * (Note: we don't set SIGCONT in ps_sigignore,
2177 * and if it is set to SIG_IGN,
2178 * action will be SIG_DFL here.)
2180 mtx_lock(&ps->ps_mtx);
2181 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2182 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2184 mtx_unlock(&ps->ps_mtx);
2185 if (ksi && (ksi->ksi_flags & KSI_INS))
2186 ksiginfo_tryfree(ksi);
2189 if (SIGISMEMBER(td->td_sigmask, sig))
2191 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2195 if (SIGISMEMBER(ps->ps_sigintr, sig))
2199 mtx_unlock(&ps->ps_mtx);
2201 if (prop & SIGPROP_CONT)
2202 sigqueue_delete_stopmask_proc(p);
2203 else if (prop & SIGPROP_STOP) {
2205 * If sending a tty stop signal to a member of an orphaned
2206 * process group, discard the signal here if the action
2207 * is default; don't stop the process below if sleeping,
2208 * and don't clear any pending SIGCONT.
2210 if ((prop & SIGPROP_TTYSTOP) &&
2211 (p->p_pgrp->pg_jobc == 0) &&
2212 (action == SIG_DFL)) {
2213 if (ksi && (ksi->ksi_flags & KSI_INS))
2214 ksiginfo_tryfree(ksi);
2217 sigqueue_delete_proc(p, SIGCONT);
2218 if (p->p_flag & P_CONTINUED) {
2219 p->p_flag &= ~P_CONTINUED;
2220 PROC_LOCK(p->p_pptr);
2221 sigqueue_take(p->p_ksi);
2222 PROC_UNLOCK(p->p_pptr);
2226 ret = sigqueue_add(sigqueue, sig, ksi);
2231 * Defer further processing for signals which are held,
2232 * except that stopped processes must be continued by SIGCONT.
2234 if (action == SIG_HOLD &&
2235 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2238 /* SIGKILL: Remove procfs STOPEVENTs. */
2239 if (sig == SIGKILL) {
2240 /* from procfs_ioctl.c: PIOCBIC */
2242 /* from procfs_ioctl.c: PIOCCONT */
2247 * Some signals have a process-wide effect and a per-thread
2248 * component. Most processing occurs when the process next
2249 * tries to cross the user boundary, however there are some
2250 * times when processing needs to be done immediately, such as
2251 * waking up threads so that they can cross the user boundary.
2252 * We try to do the per-process part here.
2254 if (P_SHOULDSTOP(p)) {
2255 KASSERT(!(p->p_flag & P_WEXIT),
2256 ("signal to stopped but exiting process"));
2257 if (sig == SIGKILL) {
2259 * If traced process is already stopped,
2260 * then no further action is necessary.
2262 if (p->p_flag & P_TRACED)
2265 * SIGKILL sets process running.
2266 * It will die elsewhere.
2267 * All threads must be restarted.
2269 p->p_flag &= ~P_STOPPED_SIG;
2273 if (prop & SIGPROP_CONT) {
2275 * If traced process is already stopped,
2276 * then no further action is necessary.
2278 if (p->p_flag & P_TRACED)
2281 * If SIGCONT is default (or ignored), we continue the
2282 * process but don't leave the signal in sigqueue as
2283 * it has no further action. If SIGCONT is held, we
2284 * continue the process and leave the signal in
2285 * sigqueue. If the process catches SIGCONT, let it
2286 * handle the signal itself. If it isn't waiting on
2287 * an event, it goes back to run state.
2288 * Otherwise, process goes back to sleep state.
2290 p->p_flag &= ~P_STOPPED_SIG;
2292 if (p->p_numthreads == p->p_suspcount) {
2294 p->p_flag |= P_CONTINUED;
2295 p->p_xsig = SIGCONT;
2296 PROC_LOCK(p->p_pptr);
2297 childproc_continued(p);
2298 PROC_UNLOCK(p->p_pptr);
2301 if (action == SIG_DFL) {
2302 thread_unsuspend(p);
2304 sigqueue_delete(sigqueue, sig);
2307 if (action == SIG_CATCH) {
2309 * The process wants to catch it so it needs
2310 * to run at least one thread, but which one?
2316 * The signal is not ignored or caught.
2318 thread_unsuspend(p);
2323 if (prop & SIGPROP_STOP) {
2325 * If traced process is already stopped,
2326 * then no further action is necessary.
2328 if (p->p_flag & P_TRACED)
2331 * Already stopped, don't need to stop again
2332 * (If we did the shell could get confused).
2333 * Just make sure the signal STOP bit set.
2335 p->p_flag |= P_STOPPED_SIG;
2336 sigqueue_delete(sigqueue, sig);
2341 * All other kinds of signals:
2342 * If a thread is sleeping interruptibly, simulate a
2343 * wakeup so that when it is continued it will be made
2344 * runnable and can look at the signal. However, don't make
2345 * the PROCESS runnable, leave it stopped.
2346 * It may run a bit until it hits a thread_suspend_check().
2351 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2352 wakeup_swapper = sleepq_abort(td, intrval);
2359 * Mutexes are short lived. Threads waiting on them will
2360 * hit thread_suspend_check() soon.
2362 } else if (p->p_state == PRS_NORMAL) {
2363 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2364 tdsigwakeup(td, sig, action, intrval);
2368 MPASS(action == SIG_DFL);
2370 if (prop & SIGPROP_STOP) {
2371 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2373 p->p_flag |= P_STOPPED_SIG;
2376 wakeup_swapper = sig_suspend_threads(td, p, 1);
2377 if (p->p_numthreads == p->p_suspcount) {
2379 * only thread sending signal to another
2380 * process can reach here, if thread is sending
2381 * signal to its process, because thread does
2382 * not suspend itself here, p_numthreads
2383 * should never be equal to p_suspcount.
2387 sigqueue_delete_proc(p, p->p_xsig);
2395 /* Not in "NORMAL" state. discard the signal. */
2396 sigqueue_delete(sigqueue, sig);
2401 * The process is not stopped so we need to apply the signal to all the
2405 tdsigwakeup(td, sig, action, intrval);
2407 thread_unsuspend(p);
2410 /* If we jump here, proc slock should not be owned. */
2411 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2416 * The force of a signal has been directed against a single
2417 * thread. We need to see what we can do about knocking it
2418 * out of any sleep it may be in etc.
2421 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2423 struct proc *p = td->td_proc;
2428 PROC_LOCK_ASSERT(p, MA_OWNED);
2429 prop = sigprop(sig);
2434 * Bring the priority of a thread up if we want it to get
2435 * killed in this lifetime. Be careful to avoid bumping the
2436 * priority of the idle thread, since we still allow to signal
2439 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2440 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2441 sched_prio(td, PUSER);
2442 if (TD_ON_SLEEPQ(td)) {
2444 * If thread is sleeping uninterruptibly
2445 * we can't interrupt the sleep... the signal will
2446 * be noticed when the process returns through
2447 * trap() or syscall().
2449 if ((td->td_flags & TDF_SINTR) == 0)
2452 * If SIGCONT is default (or ignored) and process is
2453 * asleep, we are finished; the process should not
2456 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2459 sigqueue_delete(&p->p_sigqueue, sig);
2461 * It may be on either list in this state.
2462 * Remove from both for now.
2464 sigqueue_delete(&td->td_sigqueue, sig);
2469 * Don't awaken a sleeping thread for SIGSTOP if the
2470 * STOP signal is deferred.
2472 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2473 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2477 * Give low priority threads a better chance to run.
2479 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2480 sched_prio(td, PUSER);
2482 wakeup_swapper = sleepq_abort(td, intrval);
2485 * Other states do nothing with the signal immediately,
2486 * other than kicking ourselves if we are running.
2487 * It will either never be noticed, or noticed very soon.
2490 if (TD_IS_RUNNING(td) && td != curthread)
2502 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2507 PROC_LOCK_ASSERT(p, MA_OWNED);
2508 PROC_SLOCK_ASSERT(p, MA_OWNED);
2509 MPASS(sending || td == curthread);
2512 FOREACH_THREAD_IN_PROC(p, td2) {
2514 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2515 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2516 (td2->td_flags & TDF_SINTR)) {
2517 if (td2->td_flags & TDF_SBDRY) {
2519 * Once a thread is asleep with
2520 * TDF_SBDRY and without TDF_SERESTART
2521 * or TDF_SEINTR set, it should never
2522 * become suspended due to this check.
2524 KASSERT(!TD_IS_SUSPENDED(td2),
2525 ("thread with deferred stops suspended"));
2526 if (TD_SBDRY_INTR(td2))
2527 wakeup_swapper |= sleepq_abort(td2,
2528 TD_SBDRY_ERRNO(td2));
2529 } else if (!TD_IS_SUSPENDED(td2)) {
2530 thread_suspend_one(td2);
2532 } else if (!TD_IS_SUSPENDED(td2)) {
2533 if (sending || td != td2)
2534 td2->td_flags |= TDF_ASTPENDING;
2536 if (TD_IS_RUNNING(td2) && td2 != td)
2537 forward_signal(td2);
2542 return (wakeup_swapper);
2546 * Stop the process for an event deemed interesting to the debugger. If si is
2547 * non-NULL, this is a signal exchange; the new signal requested by the
2548 * debugger will be returned for handling. If si is NULL, this is some other
2549 * type of interesting event. The debugger may request a signal be delivered in
2550 * that case as well, however it will be deferred until it can be handled.
2553 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2555 struct proc *p = td->td_proc;
2560 PROC_LOCK_ASSERT(p, MA_OWNED);
2561 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2562 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2563 &p->p_mtx.lock_object, "Stopping for traced signal");
2567 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2568 td->td_dbgflags |= TDB_XSIG;
2569 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2570 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2572 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2575 * Ensure that, if we've been PT_KILLed, the
2576 * exit status reflects that. Another thread
2577 * may also be in ptracestop(), having just
2578 * received the SIGKILL, but this thread was
2579 * unsuspended first.
2581 td->td_dbgflags &= ~TDB_XSIG;
2582 td->td_xsig = SIGKILL;
2586 if (p->p_flag & P_SINGLE_EXIT &&
2587 !(td->td_dbgflags & TDB_EXIT)) {
2589 * Ignore ptrace stops except for thread exit
2590 * events when the process exits.
2592 td->td_dbgflags &= ~TDB_XSIG;
2598 * Make wait(2) work. Ensure that right after the
2599 * attach, the thread which was decided to become the
2600 * leader of attach gets reported to the waiter.
2601 * Otherwise, just avoid overwriting another thread's
2602 * assignment to p_xthread. If another thread has
2603 * already set p_xthread, the current thread will get
2604 * a chance to report itself upon the next iteration.
2606 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2607 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2608 p->p_xthread == NULL)) {
2613 * If we are on sleepqueue already,
2614 * let sleepqueue code decide if it
2615 * needs to go sleep after attach.
2617 if (td->td_wchan == NULL)
2618 td->td_dbgflags &= ~TDB_FSTP;
2620 p->p_flag2 &= ~P2_PTRACE_FSTP;
2621 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2622 sig_suspend_threads(td, p, 0);
2624 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2625 td->td_dbgflags &= ~TDB_STOPATFORK;
2628 thread_suspend_switch(td, p);
2629 if (p->p_xthread == td)
2630 p->p_xthread = NULL;
2631 if (!(p->p_flag & P_TRACED))
2633 if (td->td_dbgflags & TDB_SUSPEND) {
2634 if (p->p_flag & P_SINGLE_EXIT)
2642 if (si != NULL && sig == td->td_xsig) {
2643 /* Parent wants us to take the original signal unchanged. */
2644 si->ksi_flags |= KSI_HEAD;
2645 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2647 } else if (td->td_xsig != 0) {
2649 * If parent wants us to take a new signal, then it will leave
2650 * it in td->td_xsig; otherwise we just look for signals again.
2652 ksiginfo_init(&ksi);
2653 ksi.ksi_signo = td->td_xsig;
2654 ksi.ksi_flags |= KSI_PTRACE;
2655 prop = sigprop(td->td_xsig);
2656 td2 = sigtd(p, td->td_xsig, prop);
2657 tdsendsignal(p, td2, td->td_xsig, &ksi);
2662 return (td->td_xsig);
2666 reschedule_signals(struct proc *p, sigset_t block, int flags)
2672 PROC_LOCK_ASSERT(p, MA_OWNED);
2674 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2675 MA_OWNED : MA_NOTOWNED);
2676 if (SIGISEMPTY(p->p_siglist))
2678 SIGSETAND(block, p->p_siglist);
2679 while ((sig = sig_ffs(&block)) != 0) {
2680 SIGDELSET(block, sig);
2681 td = sigtd(p, sig, 0);
2683 if (!(flags & SIGPROCMASK_PS_LOCKED))
2684 mtx_lock(&ps->ps_mtx);
2685 if (p->p_flag & P_TRACED ||
2686 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2687 !SIGISMEMBER(td->td_sigmask, sig)))
2688 tdsigwakeup(td, sig, SIG_CATCH,
2689 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2691 if (!(flags & SIGPROCMASK_PS_LOCKED))
2692 mtx_unlock(&ps->ps_mtx);
2697 tdsigcleanup(struct thread *td)
2703 PROC_LOCK_ASSERT(p, MA_OWNED);
2705 sigqueue_flush(&td->td_sigqueue);
2706 if (p->p_numthreads == 1)
2710 * Since we cannot handle signals, notify signal post code
2711 * about this by filling the sigmask.
2713 * Also, if needed, wake up thread(s) that do not block the
2714 * same signals as the exiting thread, since the thread might
2715 * have been selected for delivery and woken up.
2717 SIGFILLSET(unblocked);
2718 SIGSETNAND(unblocked, td->td_sigmask);
2719 SIGFILLSET(td->td_sigmask);
2720 reschedule_signals(p, unblocked, 0);
2725 sigdeferstop_curr_flags(int cflags)
2728 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2729 (cflags & TDF_SBDRY) != 0);
2730 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2734 * Defer the delivery of SIGSTOP for the current thread, according to
2735 * the requested mode. Returns previous flags, which must be restored
2736 * by sigallowstop().
2738 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2739 * cleared by the current thread, which allow the lock-less read-only
2743 sigdeferstop_impl(int mode)
2749 cflags = sigdeferstop_curr_flags(td->td_flags);
2751 case SIGDEFERSTOP_NOP:
2754 case SIGDEFERSTOP_OFF:
2757 case SIGDEFERSTOP_SILENT:
2758 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2760 case SIGDEFERSTOP_EINTR:
2761 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2763 case SIGDEFERSTOP_ERESTART:
2764 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2767 panic("sigdeferstop: invalid mode %x", mode);
2770 if (cflags == nflags)
2771 return (SIGDEFERSTOP_VAL_NCHG);
2773 td->td_flags = (td->td_flags & ~cflags) | nflags;
2779 * Restores the STOP handling mode, typically permitting the delivery
2780 * of SIGSTOP for the current thread. This does not immediately
2781 * suspend if a stop was posted. Instead, the thread will suspend
2782 * either via ast() or a subsequent interruptible sleep.
2785 sigallowstop_impl(int prev)
2790 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2791 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2792 ("sigallowstop: incorrect previous mode %x", prev));
2794 cflags = sigdeferstop_curr_flags(td->td_flags);
2795 if (cflags != prev) {
2797 td->td_flags = (td->td_flags & ~cflags) | prev;
2803 * If the current process has received a signal (should be caught or cause
2804 * termination, should interrupt current syscall), return the signal number.
2805 * Stop signals with default action are processed immediately, then cleared;
2806 * they aren't returned. This is checked after each entry to the system for
2807 * a syscall or trap (though this can usually be done without calling issignal
2808 * by checking the pending signal masks in cursig.) The normal call
2811 * while (sig = cursig(curthread))
2815 issignal(struct thread *td)
2819 struct sigqueue *queue;
2820 sigset_t sigpending;
2822 int prop, sig, traced;
2826 mtx_assert(&ps->ps_mtx, MA_OWNED);
2827 PROC_LOCK_ASSERT(p, MA_OWNED);
2829 traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2831 sigpending = td->td_sigqueue.sq_signals;
2832 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2833 SIGSETNAND(sigpending, td->td_sigmask);
2835 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
2836 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2837 SIG_STOPSIGMASK(sigpending);
2838 if (SIGISEMPTY(sigpending)) /* no signal to send */
2840 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2841 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2842 SIGISMEMBER(sigpending, SIGSTOP)) {
2844 * If debugger just attached, always consume
2845 * SIGSTOP from ptrace(PT_ATTACH) first, to
2846 * execute the debugger attach ritual in
2850 td->td_dbgflags |= TDB_FSTP;
2852 sig = sig_ffs(&sigpending);
2855 if (p->p_stops & S_SIG) {
2856 mtx_unlock(&ps->ps_mtx);
2857 stopevent(p, S_SIG, sig);
2858 mtx_lock(&ps->ps_mtx);
2862 * We should see pending but ignored signals
2863 * only if P_TRACED was on when they were posted.
2865 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2866 sigqueue_delete(&td->td_sigqueue, sig);
2867 sigqueue_delete(&p->p_sigqueue, sig);
2870 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2872 * If traced, always stop.
2873 * Remove old signal from queue before the stop.
2874 * XXX shrug off debugger, it causes siginfo to
2877 queue = &td->td_sigqueue;
2878 ksiginfo_init(&ksi);
2879 if (sigqueue_get(queue, sig, &ksi) == 0) {
2880 queue = &p->p_sigqueue;
2881 sigqueue_get(queue, sig, &ksi);
2883 td->td_si = ksi.ksi_info;
2885 mtx_unlock(&ps->ps_mtx);
2886 sig = ptracestop(td, sig, &ksi);
2887 mtx_lock(&ps->ps_mtx);
2889 td->td_si.si_signo = 0;
2892 * Keep looking if the debugger discarded or
2893 * replaced the signal.
2899 * If the signal became masked, re-queue it.
2901 if (SIGISMEMBER(td->td_sigmask, sig)) {
2902 ksi.ksi_flags |= KSI_HEAD;
2903 sigqueue_add(&p->p_sigqueue, sig, &ksi);
2908 * If the traced bit got turned off, requeue
2909 * the signal and go back up to the top to
2910 * rescan signals. This ensures that p_sig*
2911 * and p_sigact are consistent.
2913 if ((p->p_flag & P_TRACED) == 0) {
2914 ksi.ksi_flags |= KSI_HEAD;
2915 sigqueue_add(queue, sig, &ksi);
2920 prop = sigprop(sig);
2923 * Decide whether the signal should be returned.
2924 * Return the signal's number, or fall through
2925 * to clear it from the pending mask.
2927 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2929 case (intptr_t)SIG_DFL:
2931 * Don't take default actions on system processes.
2933 if (p->p_pid <= 1) {
2936 * Are you sure you want to ignore SIGSEGV
2939 printf("Process (pid %lu) got signal %d\n",
2940 (u_long)p->p_pid, sig);
2942 break; /* == ignore */
2945 * If there is a pending stop signal to process with
2946 * default action, stop here, then clear the signal.
2947 * Traced or exiting processes should ignore stops.
2948 * Additionally, a member of an orphaned process group
2949 * should ignore tty stops.
2951 if (prop & SIGPROP_STOP) {
2953 (P_TRACED | P_WEXIT | P_SINGLE_EXIT) ||
2954 (p->p_pgrp->pg_jobc == 0 &&
2955 prop & SIGPROP_TTYSTOP))
2956 break; /* == ignore */
2957 if (TD_SBDRY_INTR(td)) {
2958 KASSERT((td->td_flags & TDF_SBDRY) != 0,
2959 ("lost TDF_SBDRY"));
2962 mtx_unlock(&ps->ps_mtx);
2963 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2964 &p->p_mtx.lock_object, "Catching SIGSTOP");
2965 sigqueue_delete(&td->td_sigqueue, sig);
2966 sigqueue_delete(&p->p_sigqueue, sig);
2967 p->p_flag |= P_STOPPED_SIG;
2970 sig_suspend_threads(td, p, 0);
2971 thread_suspend_switch(td, p);
2973 mtx_lock(&ps->ps_mtx);
2975 } else if (prop & SIGPROP_IGNORE) {
2977 * Except for SIGCONT, shouldn't get here.
2978 * Default action is to ignore; drop it.
2980 break; /* == ignore */
2985 case (intptr_t)SIG_IGN:
2987 * Masking above should prevent us ever trying
2988 * to take action on an ignored signal other
2989 * than SIGCONT, unless process is traced.
2991 if ((prop & SIGPROP_CONT) == 0 &&
2992 (p->p_flag & P_TRACED) == 0)
2993 printf("issignal\n");
2994 break; /* == ignore */
2998 * This signal has an action, let
2999 * postsig() process it.
3003 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
3004 sigqueue_delete(&p->p_sigqueue, sig);
3011 thread_stopped(struct proc *p)
3015 PROC_LOCK_ASSERT(p, MA_OWNED);
3016 PROC_SLOCK_ASSERT(p, MA_OWNED);
3020 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
3022 p->p_flag &= ~P_WAITED;
3023 PROC_LOCK(p->p_pptr);
3024 childproc_stopped(p, (p->p_flag & P_TRACED) ?
3025 CLD_TRAPPED : CLD_STOPPED);
3026 PROC_UNLOCK(p->p_pptr);
3032 * Take the action for the specified signal
3033 * from the current set of pending signals.
3043 sigset_t returnmask;
3045 KASSERT(sig != 0, ("postsig"));
3049 PROC_LOCK_ASSERT(p, MA_OWNED);
3051 mtx_assert(&ps->ps_mtx, MA_OWNED);
3052 ksiginfo_init(&ksi);
3053 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3054 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3056 ksi.ksi_signo = sig;
3057 if (ksi.ksi_code == SI_TIMER)
3058 itimer_accept(p, ksi.ksi_timerid, &ksi);
3059 action = ps->ps_sigact[_SIG_IDX(sig)];
3061 if (KTRPOINT(td, KTR_PSIG))
3062 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3063 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3065 if ((p->p_stops & S_SIG) != 0) {
3066 mtx_unlock(&ps->ps_mtx);
3067 stopevent(p, S_SIG, sig);
3068 mtx_lock(&ps->ps_mtx);
3071 if (action == SIG_DFL) {
3073 * Default action, where the default is to kill
3074 * the process. (Other cases were ignored above.)
3076 mtx_unlock(&ps->ps_mtx);
3077 proc_td_siginfo_capture(td, &ksi.ksi_info);
3082 * If we get here, the signal must be caught.
3084 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3085 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3086 ("postsig action: blocked sig %d", sig));
3089 * Set the new mask value and also defer further
3090 * occurrences of this signal.
3092 * Special case: user has done a sigsuspend. Here the
3093 * current mask is not of interest, but rather the
3094 * mask from before the sigsuspend is what we want
3095 * restored after the signal processing is completed.
3097 if (td->td_pflags & TDP_OLDMASK) {
3098 returnmask = td->td_oldsigmask;
3099 td->td_pflags &= ~TDP_OLDMASK;
3101 returnmask = td->td_sigmask;
3103 if (p->p_sig == sig) {
3106 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3107 postsig_done(sig, td, ps);
3113 proc_wkilled(struct proc *p)
3116 PROC_LOCK_ASSERT(p, MA_OWNED);
3117 if ((p->p_flag & P_WKILLED) == 0) {
3118 p->p_flag |= P_WKILLED;
3120 * Notify swapper that there is a process to swap in.
3121 * The notification is racy, at worst it would take 10
3122 * seconds for the swapper process to notice.
3124 if ((p->p_flag & (P_INMEM | P_SWAPPINGIN)) == 0)
3130 * Kill the current process for stated reason.
3133 killproc(struct proc *p, char *why)
3136 PROC_LOCK_ASSERT(p, MA_OWNED);
3137 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3139 log(LOG_ERR, "pid %d (%s), jid %d, uid %d, was killed: %s\n",
3140 p->p_pid, p->p_comm, p->p_ucred->cr_prison->pr_id,
3141 p->p_ucred->cr_uid, why);
3143 kern_psignal(p, SIGKILL);
3147 * Force the current process to exit with the specified signal, dumping core
3148 * if appropriate. We bypass the normal tests for masked and caught signals,
3149 * allowing unrecoverable failures to terminate the process without changing
3150 * signal state. Mark the accounting record with the signal termination.
3151 * If dumping core, save the signal number for the debugger. Calls exit and
3155 sigexit(struct thread *td, int sig)
3157 struct proc *p = td->td_proc;
3159 PROC_LOCK_ASSERT(p, MA_OWNED);
3160 p->p_acflag |= AXSIG;
3162 * We must be single-threading to generate a core dump. This
3163 * ensures that the registers in the core file are up-to-date.
3164 * Also, the ELF dump handler assumes that the thread list doesn't
3165 * change out from under it.
3167 * XXX If another thread attempts to single-thread before us
3168 * (e.g. via fork()), we won't get a dump at all.
3170 if ((sigprop(sig) & SIGPROP_CORE) &&
3171 thread_single(p, SINGLE_NO_EXIT) == 0) {
3174 * Log signals which would cause core dumps
3175 * (Log as LOG_INFO to appease those who don't want
3177 * XXX : Todo, as well as euid, write out ruid too
3178 * Note that coredump() drops proc lock.
3180 if (coredump(td) == 0)
3182 if (kern_logsigexit)
3184 "pid %d (%s), jid %d, uid %d: exited on "
3185 "signal %d%s\n", p->p_pid, p->p_comm,
3186 p->p_ucred->cr_prison->pr_id,
3187 td->td_ucred->cr_uid,
3189 sig & WCOREFLAG ? " (core dumped)" : "");
3197 * Send queued SIGCHLD to parent when child process's state
3201 sigparent(struct proc *p, int reason, int status)
3203 PROC_LOCK_ASSERT(p, MA_OWNED);
3204 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3206 if (p->p_ksi != NULL) {
3207 p->p_ksi->ksi_signo = SIGCHLD;
3208 p->p_ksi->ksi_code = reason;
3209 p->p_ksi->ksi_status = status;
3210 p->p_ksi->ksi_pid = p->p_pid;
3211 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3212 if (KSI_ONQ(p->p_ksi))
3215 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3219 childproc_jobstate(struct proc *p, int reason, int sig)
3223 PROC_LOCK_ASSERT(p, MA_OWNED);
3224 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3227 * Wake up parent sleeping in kern_wait(), also send
3228 * SIGCHLD to parent, but SIGCHLD does not guarantee
3229 * that parent will awake, because parent may masked
3232 p->p_pptr->p_flag |= P_STATCHILD;
3235 ps = p->p_pptr->p_sigacts;
3236 mtx_lock(&ps->ps_mtx);
3237 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3238 mtx_unlock(&ps->ps_mtx);
3239 sigparent(p, reason, sig);
3241 mtx_unlock(&ps->ps_mtx);
3245 childproc_stopped(struct proc *p, int reason)
3248 childproc_jobstate(p, reason, p->p_xsig);
3252 childproc_continued(struct proc *p)
3254 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3258 childproc_exited(struct proc *p)
3262 if (WCOREDUMP(p->p_xsig)) {
3263 reason = CLD_DUMPED;
3264 status = WTERMSIG(p->p_xsig);
3265 } else if (WIFSIGNALED(p->p_xsig)) {
3266 reason = CLD_KILLED;
3267 status = WTERMSIG(p->p_xsig);
3269 reason = CLD_EXITED;
3270 status = p->p_xexit;
3273 * XXX avoid calling wakeup(p->p_pptr), the work is
3276 sigparent(p, reason, status);
3279 #define MAX_NUM_CORE_FILES 100000
3280 #ifndef NUM_CORE_FILES
3281 #define NUM_CORE_FILES 5
3283 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3284 static int num_cores = NUM_CORE_FILES;
3287 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3292 new_val = num_cores;
3293 error = sysctl_handle_int(oidp, &new_val, 0, req);
3294 if (error != 0 || req->newptr == NULL)
3296 if (new_val > MAX_NUM_CORE_FILES)
3297 new_val = MAX_NUM_CORE_FILES;
3300 num_cores = new_val;
3303 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3304 0, sizeof(int), sysctl_debug_num_cores_check, "I",
3305 "Maximum number of generated process corefiles while using index format");
3307 #define GZIP_SUFFIX ".gz"
3308 #define ZSTD_SUFFIX ".zst"
3310 int compress_user_cores = 0;
3313 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3317 val = compress_user_cores;
3318 error = sysctl_handle_int(oidp, &val, 0, req);
3319 if (error != 0 || req->newptr == NULL)
3321 if (val != 0 && !compressor_avail(val))
3323 compress_user_cores = val;
3326 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores, CTLTYPE_INT | CTLFLAG_RWTUN,
3327 0, sizeof(int), sysctl_compress_user_cores, "I",
3328 "Enable compression of user corefiles ("
3329 __XSTRING(COMPRESS_GZIP) " = gzip, "
3330 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3332 int compress_user_cores_level = 6;
3333 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3334 &compress_user_cores_level, 0,
3335 "Corefile compression level");
3338 * Protect the access to corefilename[] by allproc_lock.
3340 #define corefilename_lock allproc_lock
3342 static char corefilename[MAXPATHLEN] = {"%N.core"};
3343 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3346 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3350 sx_xlock(&corefilename_lock);
3351 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3353 sx_xunlock(&corefilename_lock);
3357 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3358 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3359 "Process corefile name format string");
3362 vnode_close_locked(struct thread *td, struct vnode *vp)
3366 vn_close(vp, FWRITE, td->td_ucred, td);
3370 * If the core format has a %I in it, then we need to check
3371 * for existing corefiles before defining a name.
3372 * To do this we iterate over 0..ncores to find a
3373 * non-existing core file name to use. If all core files are
3374 * already used we choose the oldest one.
3377 corefile_open_last(struct thread *td, char *name, int indexpos,
3378 int indexlen, int ncores, struct vnode **vpp)
3380 struct vnode *oldvp, *nextvp, *vp;
3382 struct nameidata nd;
3383 int error, i, flags, oflags, cmode;
3385 struct timespec lasttime;
3387 nextvp = oldvp = NULL;
3388 cmode = S_IRUSR | S_IWUSR;
3389 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3390 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3392 for (i = 0; i < ncores; i++) {
3393 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3395 ch = name[indexpos + indexlen];
3396 (void)snprintf(name + indexpos, indexlen + 1, "%.*u", indexlen,
3398 name[indexpos + indexlen] = ch;
3400 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3401 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3407 NDFREE(&nd, NDF_ONLY_PNBUF);
3408 if ((flags & O_CREAT) == O_CREAT) {
3413 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
3415 vnode_close_locked(td, vp);
3419 if (oldvp == NULL ||
3420 lasttime.tv_sec > vattr.va_mtime.tv_sec ||
3421 (lasttime.tv_sec == vattr.va_mtime.tv_sec &&
3422 lasttime.tv_nsec >= vattr.va_mtime.tv_nsec)) {
3424 vnode_close_locked(td, oldvp);
3426 lasttime = vattr.va_mtime;
3428 vnode_close_locked(td, vp);
3432 if (oldvp != NULL) {
3433 if (nextvp == NULL) {
3434 if ((td->td_proc->p_flag & P_SUGID) != 0) {
3436 vnode_close_locked(td, oldvp);
3441 vnode_close_locked(td, oldvp);
3446 vnode_close_locked(td, oldvp);
3455 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3456 * Expand the name described in corefilename, using name, uid, and pid
3457 * and open/create core file.
3458 * corefilename is a printf-like string, with three format specifiers:
3459 * %N name of process ("name")
3460 * %P process id (pid)
3462 * For example, "%N.core" is the default; they can be disabled completely
3463 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3464 * This is controlled by the sysctl variable kern.corefile (see above).
3467 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3468 int compress, int signum, struct vnode **vpp, char **namep)
3471 struct nameidata nd;
3473 char *hostname, *name;
3474 int cmode, error, flags, i, indexpos, indexlen, oflags, ncores;
3477 format = corefilename;
3478 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3482 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3483 sx_slock(&corefilename_lock);
3484 for (i = 0; format[i] != '\0'; i++) {
3485 switch (format[i]) {
3486 case '%': /* Format character */
3488 switch (format[i]) {
3490 sbuf_putc(&sb, '%');
3492 case 'H': /* hostname */
3493 if (hostname == NULL) {
3494 hostname = malloc(MAXHOSTNAMELEN,
3497 getcredhostname(td->td_ucred, hostname,
3499 sbuf_printf(&sb, "%s", hostname);
3501 case 'I': /* autoincrementing index */
3502 if (indexpos != -1) {
3503 sbuf_printf(&sb, "%%I");
3507 indexpos = sbuf_len(&sb);
3508 sbuf_printf(&sb, "%u", ncores - 1);
3509 indexlen = sbuf_len(&sb) - indexpos;
3511 case 'N': /* process name */
3512 sbuf_printf(&sb, "%s", comm);
3514 case 'P': /* process id */
3515 sbuf_printf(&sb, "%u", pid);
3517 case 'S': /* signal number */
3518 sbuf_printf(&sb, "%i", signum);
3520 case 'U': /* user id */
3521 sbuf_printf(&sb, "%u", uid);
3525 "Unknown format character %c in "
3526 "corename `%s'\n", format[i], format);
3531 sbuf_putc(&sb, format[i]);
3535 sx_sunlock(&corefilename_lock);
3536 free(hostname, M_TEMP);
3537 if (compress == COMPRESS_GZIP)
3538 sbuf_printf(&sb, GZIP_SUFFIX);
3539 else if (compress == COMPRESS_ZSTD)
3540 sbuf_printf(&sb, ZSTD_SUFFIX);
3541 if (sbuf_error(&sb) != 0) {
3542 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3543 "long\n", (long)pid, comm, (u_long)uid);
3551 if (indexpos != -1) {
3552 error = corefile_open_last(td, name, indexpos, indexlen, ncores,
3556 "pid %d (%s), uid (%u): Path `%s' failed "
3557 "on initial open test, error = %d\n",
3558 pid, comm, uid, name, error);
3561 cmode = S_IRUSR | S_IWUSR;
3562 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3563 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3564 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3565 if ((td->td_proc->p_flag & P_SUGID) != 0)
3568 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3569 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3573 NDFREE(&nd, NDF_ONLY_PNBUF);
3579 audit_proc_coredump(td, name, error);
3589 * Dump a process' core. The main routine does some
3590 * policy checking, and creates the name of the coredump;
3591 * then it passes on a vnode and a size limit to the process-specific
3592 * coredump routine if there is one; if there _is not_ one, it returns
3593 * ENOSYS; otherwise it returns the error from the process-specific routine.
3597 coredump(struct thread *td)
3599 struct proc *p = td->td_proc;
3600 struct ucred *cred = td->td_ucred;
3604 int error, error1, locked;
3605 char *name; /* name of corefile */
3608 char *fullpath, *freepath = NULL;
3611 PROC_LOCK_ASSERT(p, MA_OWNED);
3612 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3613 _STOPEVENT(p, S_CORE, 0);
3615 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3616 (p->p_flag2 & P2_NOTRACE) != 0) {
3622 * Note that the bulk of limit checking is done after
3623 * the corefile is created. The exception is if the limit
3624 * for corefiles is 0, in which case we don't bother
3625 * creating the corefile at all. This layout means that
3626 * a corefile is truncated instead of not being created,
3627 * if it is larger than the limit.
3629 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3630 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3636 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3637 compress_user_cores, p->p_sig, &vp, &name);
3642 * Don't dump to non-regular files or files with links.
3643 * Do not dump into system files. Effective user must own the corefile.
3645 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3646 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0 ||
3647 vattr.va_uid != cred->cr_uid) {
3655 /* Postpone other writers, including core dumps of other processes. */
3656 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3658 lf.l_whence = SEEK_SET;
3661 lf.l_type = F_WRLCK;
3662 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3666 if (set_core_nodump_flag)
3667 vattr.va_flags = UF_NODUMP;
3668 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3669 VOP_SETATTR(vp, &vattr, cred);
3672 p->p_acflag |= ACORE;
3675 if (p->p_sysent->sv_coredump != NULL) {
3676 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3682 lf.l_type = F_UNLCK;
3683 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3685 vn_rangelock_unlock(vp, rl_cookie);
3688 * Notify the userland helper that a process triggered a core dump.
3689 * This allows the helper to run an automated debugging session.
3691 if (error != 0 || coredump_devctl == 0)
3693 sb = sbuf_new_auto();
3694 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3696 sbuf_printf(sb, "comm=\"");
3697 devctl_safe_quote_sb(sb, fullpath);
3698 free(freepath, M_TEMP);
3699 sbuf_printf(sb, "\" core=\"");
3702 * We can't lookup core file vp directly. When we're replacing a core, and
3703 * other random times, we flush the name cache, so it will fail. Instead,
3704 * if the path of the core is relative, add the current dir in front if it.
3706 if (name[0] != '/') {
3707 fullpath = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
3708 if (kern___getcwd(td, fullpath, UIO_SYSSPACE, MAXPATHLEN, MAXPATHLEN) != 0) {
3709 free(fullpath, M_TEMP);
3712 devctl_safe_quote_sb(sb, fullpath);
3713 free(fullpath, M_TEMP);
3716 devctl_safe_quote_sb(sb, name);
3717 sbuf_printf(sb, "\"");
3718 if (sbuf_finish(sb) == 0)
3719 devctl_notify("kernel", "signal", "coredump", sbuf_data(sb));
3723 error1 = vn_close(vp, FWRITE, cred, td);
3727 audit_proc_coredump(td, name, error);
3734 * Nonexistent system call-- signal process (may want to handle it). Flag
3735 * error in case process won't see signal immediately (blocked or ignored).
3737 #ifndef _SYS_SYSPROTO_H_
3744 nosys(struct thread *td, struct nosys_args *args)
3751 tdsignal(td, SIGSYS);
3753 if (kern_lognosys == 1 || kern_lognosys == 3) {
3754 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3757 if (kern_lognosys == 2 || kern_lognosys == 3) {
3758 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3765 * Send a SIGIO or SIGURG signal to a process or process group using stored
3766 * credentials rather than those of the current process.
3769 pgsigio(struct sigio **sigiop, int sig, int checkctty)
3772 struct sigio *sigio;
3774 ksiginfo_init(&ksi);
3775 ksi.ksi_signo = sig;
3776 ksi.ksi_code = SI_KERNEL;
3780 if (sigio == NULL) {
3784 if (sigio->sio_pgid > 0) {
3785 PROC_LOCK(sigio->sio_proc);
3786 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3787 kern_psignal(sigio->sio_proc, sig);
3788 PROC_UNLOCK(sigio->sio_proc);
3789 } else if (sigio->sio_pgid < 0) {
3792 PGRP_LOCK(sigio->sio_pgrp);
3793 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3795 if (p->p_state == PRS_NORMAL &&
3796 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3797 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3798 kern_psignal(p, sig);
3801 PGRP_UNLOCK(sigio->sio_pgrp);
3807 filt_sigattach(struct knote *kn)
3809 struct proc *p = curproc;
3811 kn->kn_ptr.p_proc = p;
3812 kn->kn_flags |= EV_CLEAR; /* automatically set */
3814 knlist_add(p->p_klist, kn, 0);
3820 filt_sigdetach(struct knote *kn)
3822 struct proc *p = kn->kn_ptr.p_proc;
3824 knlist_remove(p->p_klist, kn, 0);
3828 * signal knotes are shared with proc knotes, so we apply a mask to
3829 * the hint in order to differentiate them from process hints. This
3830 * could be avoided by using a signal-specific knote list, but probably
3831 * isn't worth the trouble.
3834 filt_signal(struct knote *kn, long hint)
3837 if (hint & NOTE_SIGNAL) {
3838 hint &= ~NOTE_SIGNAL;
3840 if (kn->kn_id == hint)
3843 return (kn->kn_data != 0);
3851 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3852 refcount_init(&ps->ps_refcnt, 1);
3853 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3858 sigacts_free(struct sigacts *ps)
3861 if (refcount_release(&ps->ps_refcnt) == 0)
3863 mtx_destroy(&ps->ps_mtx);
3864 free(ps, M_SUBPROC);
3868 sigacts_hold(struct sigacts *ps)
3871 refcount_acquire(&ps->ps_refcnt);
3876 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3879 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3880 mtx_lock(&src->ps_mtx);
3881 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3882 mtx_unlock(&src->ps_mtx);
3886 sigacts_shared(struct sigacts *ps)
3889 return (ps->ps_refcnt > 1);
3893 sig_drop_caught(struct proc *p)
3899 PROC_LOCK_ASSERT(p, MA_OWNED);
3900 mtx_assert(&ps->ps_mtx, MA_OWNED);
3901 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
3902 sig = sig_ffs(&ps->ps_sigcatch);
3904 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
3905 sigqueue_delete_proc(p, sig);