2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
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9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
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13 * modification, are permitted provided that the following conditions
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16 * notice, this list of conditions and the following disclaimer.
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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, bool fast_sigblock);
118 static void sigqueue_start(void);
120 static uma_zone_t ksiginfo_zone = NULL;
121 struct filterops sig_filtops = {
123 .f_attach = filt_sigattach,
124 .f_detach = filt_sigdetach,
125 .f_event = filt_signal,
128 static int kern_logsigexit = 1;
129 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
131 "Log processes quitting on abnormal signals to syslog(3)");
133 static int kern_forcesigexit = 1;
134 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
135 &kern_forcesigexit, 0, "Force trap signal to be handled");
137 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 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 sigset_t fastblock_mask;
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);
252 SIGFILLSET(fastblock_mask);
253 SIG_CANTMASK(fastblock_mask);
257 ksiginfo_alloc(int wait)
264 if (ksiginfo_zone != NULL)
265 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
270 ksiginfo_free(ksiginfo_t *ksi)
272 uma_zfree(ksiginfo_zone, ksi);
276 ksiginfo_tryfree(ksiginfo_t *ksi)
278 if (!(ksi->ksi_flags & KSI_EXT)) {
279 uma_zfree(ksiginfo_zone, ksi);
286 sigqueue_init(sigqueue_t *list, struct proc *p)
288 SIGEMPTYSET(list->sq_signals);
289 SIGEMPTYSET(list->sq_kill);
290 SIGEMPTYSET(list->sq_ptrace);
291 TAILQ_INIT(&list->sq_list);
293 list->sq_flags = SQ_INIT;
297 * Get a signal's ksiginfo.
299 * 0 - signal not found
300 * others - signal number
303 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
305 struct proc *p = sq->sq_proc;
306 struct ksiginfo *ksi, *next;
309 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
311 if (!SIGISMEMBER(sq->sq_signals, signo))
314 if (SIGISMEMBER(sq->sq_ptrace, signo)) {
316 SIGDELSET(sq->sq_ptrace, signo);
317 si->ksi_flags |= KSI_PTRACE;
319 if (SIGISMEMBER(sq->sq_kill, signo)) {
322 SIGDELSET(sq->sq_kill, signo);
325 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
326 if (ksi->ksi_signo == signo) {
328 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
329 ksi->ksi_sigq = NULL;
330 ksiginfo_copy(ksi, si);
331 if (ksiginfo_tryfree(ksi) && p != NULL)
340 SIGDELSET(sq->sq_signals, signo);
341 si->ksi_signo = signo;
346 sigqueue_take(ksiginfo_t *ksi)
352 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
356 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
357 ksi->ksi_sigq = NULL;
358 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
361 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
362 kp = TAILQ_NEXT(kp, ksi_link)) {
363 if (kp->ksi_signo == ksi->ksi_signo)
366 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) &&
367 !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo))
368 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
372 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
374 struct proc *p = sq->sq_proc;
375 struct ksiginfo *ksi;
378 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
381 * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path
384 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
385 SIGADDSET(sq->sq_kill, signo);
389 /* directly insert the ksi, don't copy it */
390 if (si->ksi_flags & KSI_INS) {
391 if (si->ksi_flags & KSI_HEAD)
392 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
394 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
399 if (__predict_false(ksiginfo_zone == NULL)) {
400 SIGADDSET(sq->sq_kill, signo);
404 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
407 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
413 ksiginfo_copy(si, ksi);
414 ksi->ksi_signo = signo;
415 if (si->ksi_flags & KSI_HEAD)
416 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
418 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
423 if ((si->ksi_flags & KSI_PTRACE) != 0) {
424 SIGADDSET(sq->sq_ptrace, signo);
427 } else if ((si->ksi_flags & KSI_TRAP) != 0 ||
428 (si->ksi_flags & KSI_SIGQ) == 0) {
429 SIGADDSET(sq->sq_kill, signo);
437 SIGADDSET(sq->sq_signals, signo);
442 sigqueue_flush(sigqueue_t *sq)
444 struct proc *p = sq->sq_proc;
447 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
450 PROC_LOCK_ASSERT(p, MA_OWNED);
452 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
453 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
454 ksi->ksi_sigq = NULL;
455 if (ksiginfo_tryfree(ksi) && p != NULL)
459 SIGEMPTYSET(sq->sq_signals);
460 SIGEMPTYSET(sq->sq_kill);
461 SIGEMPTYSET(sq->sq_ptrace);
465 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
468 struct proc *p1, *p2;
469 ksiginfo_t *ksi, *next;
471 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
472 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
475 /* Move siginfo to target list */
476 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
477 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
478 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
481 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
488 /* Move pending bits to target list */
490 SIGSETAND(tmp, *set);
491 SIGSETOR(dst->sq_kill, tmp);
492 SIGSETNAND(src->sq_kill, tmp);
494 tmp = src->sq_ptrace;
495 SIGSETAND(tmp, *set);
496 SIGSETOR(dst->sq_ptrace, tmp);
497 SIGSETNAND(src->sq_ptrace, tmp);
499 tmp = src->sq_signals;
500 SIGSETAND(tmp, *set);
501 SIGSETOR(dst->sq_signals, tmp);
502 SIGSETNAND(src->sq_signals, tmp);
507 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
512 SIGADDSET(set, signo);
513 sigqueue_move_set(src, dst, &set);
518 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
520 struct proc *p = sq->sq_proc;
521 ksiginfo_t *ksi, *next;
523 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
525 /* Remove siginfo queue */
526 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
527 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
528 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
529 ksi->ksi_sigq = NULL;
530 if (ksiginfo_tryfree(ksi) && p != NULL)
534 SIGSETNAND(sq->sq_kill, *set);
535 SIGSETNAND(sq->sq_ptrace, *set);
536 SIGSETNAND(sq->sq_signals, *set);
540 sigqueue_delete(sigqueue_t *sq, int signo)
545 SIGADDSET(set, signo);
546 sigqueue_delete_set(sq, &set);
549 /* Remove a set of signals for a process */
551 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
556 PROC_LOCK_ASSERT(p, MA_OWNED);
558 sigqueue_init(&worklist, NULL);
559 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
561 FOREACH_THREAD_IN_PROC(p, td0)
562 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
564 sigqueue_flush(&worklist);
568 sigqueue_delete_proc(struct proc *p, int signo)
573 SIGADDSET(set, signo);
574 sigqueue_delete_set_proc(p, &set);
578 sigqueue_delete_stopmask_proc(struct proc *p)
583 SIGADDSET(set, SIGSTOP);
584 SIGADDSET(set, SIGTSTP);
585 SIGADDSET(set, SIGTTIN);
586 SIGADDSET(set, SIGTTOU);
587 sigqueue_delete_set_proc(p, &set);
591 * Determine signal that should be delivered to thread td, the current
592 * thread, 0 if none. If there is a pending stop signal with default
593 * action, the process stops in issignal().
596 cursig(struct thread *td)
598 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
599 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
600 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
601 return (SIGPENDING(td) ? issignal(td) : 0);
605 * Arrange for ast() to handle unmasked pending signals on return to user
606 * mode. This must be called whenever a signal is added to td_sigqueue or
607 * unmasked in td_sigmask.
610 signotify(struct thread *td)
613 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
615 if (SIGPENDING(td)) {
617 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
623 * Returns 1 (true) if altstack is configured for the thread, and the
624 * passed stack bottom address falls into the altstack range. Handles
625 * the 43 compat special case where the alt stack size is zero.
628 sigonstack(size_t sp)
633 if ((td->td_pflags & TDP_ALTSTACK) == 0)
635 #if defined(COMPAT_43)
636 if (SV_PROC_FLAG(td->td_proc, SV_AOUT) && td->td_sigstk.ss_size == 0)
637 return ((td->td_sigstk.ss_flags & SS_ONSTACK) != 0);
639 return (sp >= (size_t)td->td_sigstk.ss_sp &&
640 sp < td->td_sigstk.ss_size + (size_t)td->td_sigstk.ss_sp);
647 if (sig > 0 && sig < nitems(sigproptbl))
648 return (sigproptbl[sig]);
653 sig_ffs(sigset_t *set)
657 for (i = 0; i < _SIG_WORDS; i++)
659 return (ffs(set->__bits[i]) + (i * 32));
664 sigact_flag_test(const struct sigaction *act, int flag)
668 * SA_SIGINFO is reset when signal disposition is set to
669 * ignore or default. Other flags are kept according to user
672 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
673 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
674 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
684 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
685 struct sigaction *oact, int flags)
688 struct proc *p = td->td_proc;
690 if (!_SIG_VALID(sig))
692 if (act != NULL && act->sa_handler != SIG_DFL &&
693 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
694 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
695 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
700 mtx_lock(&ps->ps_mtx);
702 memset(oact, 0, sizeof(*oact));
703 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
704 if (SIGISMEMBER(ps->ps_sigonstack, sig))
705 oact->sa_flags |= SA_ONSTACK;
706 if (!SIGISMEMBER(ps->ps_sigintr, sig))
707 oact->sa_flags |= SA_RESTART;
708 if (SIGISMEMBER(ps->ps_sigreset, sig))
709 oact->sa_flags |= SA_RESETHAND;
710 if (SIGISMEMBER(ps->ps_signodefer, sig))
711 oact->sa_flags |= SA_NODEFER;
712 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
713 oact->sa_flags |= SA_SIGINFO;
715 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
717 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
718 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
719 oact->sa_flags |= SA_NOCLDSTOP;
720 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
721 oact->sa_flags |= SA_NOCLDWAIT;
724 if ((sig == SIGKILL || sig == SIGSTOP) &&
725 act->sa_handler != SIG_DFL) {
726 mtx_unlock(&ps->ps_mtx);
732 * Change setting atomically.
735 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
736 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
737 if (sigact_flag_test(act, SA_SIGINFO)) {
738 ps->ps_sigact[_SIG_IDX(sig)] =
739 (__sighandler_t *)act->sa_sigaction;
740 SIGADDSET(ps->ps_siginfo, sig);
742 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
743 SIGDELSET(ps->ps_siginfo, sig);
745 if (!sigact_flag_test(act, SA_RESTART))
746 SIGADDSET(ps->ps_sigintr, sig);
748 SIGDELSET(ps->ps_sigintr, sig);
749 if (sigact_flag_test(act, SA_ONSTACK))
750 SIGADDSET(ps->ps_sigonstack, sig);
752 SIGDELSET(ps->ps_sigonstack, sig);
753 if (sigact_flag_test(act, SA_RESETHAND))
754 SIGADDSET(ps->ps_sigreset, sig);
756 SIGDELSET(ps->ps_sigreset, sig);
757 if (sigact_flag_test(act, SA_NODEFER))
758 SIGADDSET(ps->ps_signodefer, sig);
760 SIGDELSET(ps->ps_signodefer, sig);
761 if (sig == SIGCHLD) {
762 if (act->sa_flags & SA_NOCLDSTOP)
763 ps->ps_flag |= PS_NOCLDSTOP;
765 ps->ps_flag &= ~PS_NOCLDSTOP;
766 if (act->sa_flags & SA_NOCLDWAIT) {
768 * Paranoia: since SA_NOCLDWAIT is implemented
769 * by reparenting the dying child to PID 1 (and
770 * trust it to reap the zombie), PID 1 itself
771 * is forbidden to set SA_NOCLDWAIT.
774 ps->ps_flag &= ~PS_NOCLDWAIT;
776 ps->ps_flag |= PS_NOCLDWAIT;
778 ps->ps_flag &= ~PS_NOCLDWAIT;
779 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
780 ps->ps_flag |= PS_CLDSIGIGN;
782 ps->ps_flag &= ~PS_CLDSIGIGN;
785 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
786 * and for signals set to SIG_DFL where the default is to
787 * ignore. However, don't put SIGCONT in ps_sigignore, as we
788 * have to restart the process.
790 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
791 (sigprop(sig) & SIGPROP_IGNORE &&
792 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
793 /* never to be seen again */
794 sigqueue_delete_proc(p, sig);
796 /* easier in psignal */
797 SIGADDSET(ps->ps_sigignore, sig);
798 SIGDELSET(ps->ps_sigcatch, sig);
800 SIGDELSET(ps->ps_sigignore, sig);
801 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
802 SIGDELSET(ps->ps_sigcatch, sig);
804 SIGADDSET(ps->ps_sigcatch, sig);
806 #ifdef COMPAT_FREEBSD4
807 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
808 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
809 (flags & KSA_FREEBSD4) == 0)
810 SIGDELSET(ps->ps_freebsd4, sig);
812 SIGADDSET(ps->ps_freebsd4, sig);
815 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
816 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
817 (flags & KSA_OSIGSET) == 0)
818 SIGDELSET(ps->ps_osigset, sig);
820 SIGADDSET(ps->ps_osigset, sig);
823 mtx_unlock(&ps->ps_mtx);
828 #ifndef _SYS_SYSPROTO_H_
829 struct sigaction_args {
831 struct sigaction *act;
832 struct sigaction *oact;
836 sys_sigaction(struct thread *td, struct sigaction_args *uap)
838 struct sigaction act, oact;
839 struct sigaction *actp, *oactp;
842 actp = (uap->act != NULL) ? &act : NULL;
843 oactp = (uap->oact != NULL) ? &oact : NULL;
845 error = copyin(uap->act, actp, sizeof(act));
849 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
851 error = copyout(oactp, uap->oact, sizeof(oact));
855 #ifdef COMPAT_FREEBSD4
856 #ifndef _SYS_SYSPROTO_H_
857 struct freebsd4_sigaction_args {
859 struct sigaction *act;
860 struct sigaction *oact;
864 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
866 struct sigaction act, oact;
867 struct sigaction *actp, *oactp;
870 actp = (uap->act != NULL) ? &act : NULL;
871 oactp = (uap->oact != NULL) ? &oact : NULL;
873 error = copyin(uap->act, actp, sizeof(act));
877 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
879 error = copyout(oactp, uap->oact, sizeof(oact));
882 #endif /* COMAPT_FREEBSD4 */
884 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
885 #ifndef _SYS_SYSPROTO_H_
886 struct osigaction_args {
888 struct osigaction *nsa;
889 struct osigaction *osa;
893 osigaction(struct thread *td, struct osigaction_args *uap)
895 struct osigaction sa;
896 struct sigaction nsa, osa;
897 struct sigaction *nsap, *osap;
900 if (uap->signum <= 0 || uap->signum >= ONSIG)
903 nsap = (uap->nsa != NULL) ? &nsa : NULL;
904 osap = (uap->osa != NULL) ? &osa : NULL;
907 error = copyin(uap->nsa, &sa, sizeof(sa));
910 nsap->sa_handler = sa.sa_handler;
911 nsap->sa_flags = sa.sa_flags;
912 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
914 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
915 if (osap && !error) {
916 sa.sa_handler = osap->sa_handler;
917 sa.sa_flags = osap->sa_flags;
918 SIG2OSIG(osap->sa_mask, sa.sa_mask);
919 error = copyout(&sa, uap->osa, sizeof(sa));
924 #if !defined(__i386__)
925 /* Avoid replicating the same stub everywhere */
927 osigreturn(struct thread *td, struct osigreturn_args *uap)
930 return (nosys(td, (struct nosys_args *)uap));
933 #endif /* COMPAT_43 */
936 * Initialize signal state for process 0;
937 * set to ignore signals that are ignored by default.
940 siginit(struct proc *p)
947 mtx_lock(&ps->ps_mtx);
948 for (i = 1; i <= NSIG; i++) {
949 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
950 SIGADDSET(ps->ps_sigignore, i);
953 mtx_unlock(&ps->ps_mtx);
958 * Reset specified signal to the default disposition.
961 sigdflt(struct sigacts *ps, int sig)
964 mtx_assert(&ps->ps_mtx, MA_OWNED);
965 SIGDELSET(ps->ps_sigcatch, sig);
966 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
967 SIGADDSET(ps->ps_sigignore, sig);
968 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
969 SIGDELSET(ps->ps_siginfo, sig);
973 * Reset signals for an exec of the specified process.
976 execsigs(struct proc *p)
984 * Reset caught signals. Held signals remain held
985 * through td_sigmask (unless they were caught,
986 * and are now ignored by default).
988 PROC_LOCK_ASSERT(p, MA_OWNED);
990 mtx_lock(&ps->ps_mtx);
994 * As CloudABI processes cannot modify signal handlers, fully
995 * reset all signals to their default behavior. Do ignore
996 * SIGPIPE, as it would otherwise be impossible to recover from
997 * writes to broken pipes and sockets.
999 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
1000 osigignore = ps->ps_sigignore;
1001 while (SIGNOTEMPTY(osigignore)) {
1002 sig = sig_ffs(&osigignore);
1003 SIGDELSET(osigignore, sig);
1007 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1011 * Reset stack state to the user stack.
1012 * Clear set of signals caught on the signal stack.
1015 MPASS(td->td_proc == p);
1016 td->td_sigstk.ss_flags = SS_DISABLE;
1017 td->td_sigstk.ss_size = 0;
1018 td->td_sigstk.ss_sp = 0;
1019 td->td_pflags &= ~TDP_ALTSTACK;
1021 * Reset no zombies if child dies flag as Solaris does.
1023 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1024 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1025 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1026 mtx_unlock(&ps->ps_mtx);
1030 * kern_sigprocmask()
1032 * Manipulate signal mask.
1035 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1038 sigset_t new_block, oset1;
1043 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1044 PROC_LOCK_ASSERT(p, MA_OWNED);
1047 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1048 ? MA_OWNED : MA_NOTOWNED);
1050 *oset = td->td_sigmask;
1057 oset1 = td->td_sigmask;
1058 SIGSETOR(td->td_sigmask, *set);
1059 new_block = td->td_sigmask;
1060 SIGSETNAND(new_block, oset1);
1063 SIGSETNAND(td->td_sigmask, *set);
1068 oset1 = td->td_sigmask;
1069 if (flags & SIGPROCMASK_OLD)
1070 SIGSETLO(td->td_sigmask, *set);
1072 td->td_sigmask = *set;
1073 new_block = td->td_sigmask;
1074 SIGSETNAND(new_block, oset1);
1083 * The new_block set contains signals that were not previously
1084 * blocked, but are blocked now.
1086 * In case we block any signal that was not previously blocked
1087 * for td, and process has the signal pending, try to schedule
1088 * signal delivery to some thread that does not block the
1089 * signal, possibly waking it up.
1091 if (p->p_numthreads != 1)
1092 reschedule_signals(p, new_block, flags);
1096 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1101 #ifndef _SYS_SYSPROTO_H_
1102 struct sigprocmask_args {
1104 const sigset_t *set;
1109 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1112 sigset_t *setp, *osetp;
1115 setp = (uap->set != NULL) ? &set : NULL;
1116 osetp = (uap->oset != NULL) ? &oset : NULL;
1118 error = copyin(uap->set, setp, sizeof(set));
1122 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1123 if (osetp && !error) {
1124 error = copyout(osetp, uap->oset, sizeof(oset));
1129 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1130 #ifndef _SYS_SYSPROTO_H_
1131 struct osigprocmask_args {
1137 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1142 OSIG2SIG(uap->mask, set);
1143 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1144 SIG2OSIG(oset, td->td_retval[0]);
1147 #endif /* COMPAT_43 */
1150 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1156 error = copyin(uap->set, &set, sizeof(set));
1158 td->td_retval[0] = error;
1162 error = kern_sigtimedwait(td, set, &ksi, NULL);
1164 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1166 if (error == ERESTART)
1168 td->td_retval[0] = error;
1172 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1173 td->td_retval[0] = error;
1178 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1181 struct timespec *timeout;
1187 error = copyin(uap->timeout, &ts, sizeof(ts));
1195 error = copyin(uap->set, &set, sizeof(set));
1199 error = kern_sigtimedwait(td, set, &ksi, timeout);
1204 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1207 td->td_retval[0] = ksi.ksi_signo;
1212 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1218 error = copyin(uap->set, &set, sizeof(set));
1222 error = kern_sigtimedwait(td, set, &ksi, NULL);
1227 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1230 td->td_retval[0] = ksi.ksi_signo;
1235 proc_td_siginfo_capture(struct thread *td, siginfo_t *si)
1239 FOREACH_THREAD_IN_PROC(td->td_proc, thr) {
1243 thr->td_si.si_signo = 0;
1248 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1249 struct timespec *timeout)
1252 sigset_t saved_mask, new_block;
1254 int error, sig, timo, timevalid = 0;
1255 struct timespec rts, ets, ts;
1265 if (timeout != NULL) {
1266 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1268 getnanouptime(&rts);
1269 timespecadd(&rts, timeout, &ets);
1273 /* Some signals can not be waited for. */
1274 SIG_CANTMASK(waitset);
1277 saved_mask = td->td_sigmask;
1278 SIGSETNAND(td->td_sigmask, waitset);
1280 mtx_lock(&ps->ps_mtx);
1282 mtx_unlock(&ps->ps_mtx);
1283 KASSERT(sig >= 0, ("sig %d", sig));
1284 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1285 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1286 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1296 * POSIX says this must be checked after looking for pending
1299 if (timeout != NULL) {
1304 getnanouptime(&rts);
1305 if (timespeccmp(&rts, &ets, >=)) {
1309 timespecsub(&ets, &rts, &ts);
1310 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1321 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1323 if (timeout != NULL) {
1324 if (error == ERESTART) {
1325 /* Timeout can not be restarted. */
1327 } else if (error == EAGAIN) {
1328 /* We will calculate timeout by ourself. */
1334 * If PTRACE_SCE or PTRACE_SCX were set after
1335 * userspace entered the syscall, return spurious
1336 * EINTR after wait was done. Only do this as last
1337 * resort after rechecking for possible queued signals
1338 * and expired timeouts.
1340 if (error == 0 && (p->p_ptevents & PTRACE_SYSCALL) != 0)
1344 new_block = saved_mask;
1345 SIGSETNAND(new_block, td->td_sigmask);
1346 td->td_sigmask = saved_mask;
1348 * Fewer signals can be delivered to us, reschedule signal
1351 if (p->p_numthreads != 1)
1352 reschedule_signals(p, new_block, 0);
1355 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1357 if (ksi->ksi_code == SI_TIMER)
1358 itimer_accept(p, ksi->ksi_timerid, ksi);
1361 if (KTRPOINT(td, KTR_PSIG)) {
1364 mtx_lock(&ps->ps_mtx);
1365 action = ps->ps_sigact[_SIG_IDX(sig)];
1366 mtx_unlock(&ps->ps_mtx);
1367 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1370 if (sig == SIGKILL) {
1371 proc_td_siginfo_capture(td, &ksi->ksi_info);
1379 #ifndef _SYS_SYSPROTO_H_
1380 struct sigpending_args {
1385 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1387 struct proc *p = td->td_proc;
1391 pending = p->p_sigqueue.sq_signals;
1392 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1394 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1397 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1398 #ifndef _SYS_SYSPROTO_H_
1399 struct osigpending_args {
1404 osigpending(struct thread *td, struct osigpending_args *uap)
1406 struct proc *p = td->td_proc;
1410 pending = p->p_sigqueue.sq_signals;
1411 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1413 SIG2OSIG(pending, td->td_retval[0]);
1416 #endif /* COMPAT_43 */
1418 #if defined(COMPAT_43)
1420 * Generalized interface signal handler, 4.3-compatible.
1422 #ifndef _SYS_SYSPROTO_H_
1423 struct osigvec_args {
1431 osigvec(struct thread *td, struct osigvec_args *uap)
1434 struct sigaction nsa, osa;
1435 struct sigaction *nsap, *osap;
1438 if (uap->signum <= 0 || uap->signum >= ONSIG)
1440 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1441 osap = (uap->osv != NULL) ? &osa : NULL;
1443 error = copyin(uap->nsv, &vec, sizeof(vec));
1446 nsap->sa_handler = vec.sv_handler;
1447 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1448 nsap->sa_flags = vec.sv_flags;
1449 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1451 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1452 if (osap && !error) {
1453 vec.sv_handler = osap->sa_handler;
1454 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1455 vec.sv_flags = osap->sa_flags;
1456 vec.sv_flags &= ~SA_NOCLDWAIT;
1457 vec.sv_flags ^= SA_RESTART;
1458 error = copyout(&vec, uap->osv, sizeof(vec));
1463 #ifndef _SYS_SYSPROTO_H_
1464 struct osigblock_args {
1469 osigblock(struct thread *td, struct osigblock_args *uap)
1473 OSIG2SIG(uap->mask, set);
1474 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1475 SIG2OSIG(oset, td->td_retval[0]);
1479 #ifndef _SYS_SYSPROTO_H_
1480 struct osigsetmask_args {
1485 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1489 OSIG2SIG(uap->mask, set);
1490 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1491 SIG2OSIG(oset, td->td_retval[0]);
1494 #endif /* COMPAT_43 */
1497 * Suspend calling thread until signal, providing mask to be set in the
1500 #ifndef _SYS_SYSPROTO_H_
1501 struct sigsuspend_args {
1502 const sigset_t *sigmask;
1507 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1512 error = copyin(uap->sigmask, &mask, sizeof(mask));
1515 return (kern_sigsuspend(td, mask));
1519 kern_sigsuspend(struct thread *td, sigset_t mask)
1521 struct proc *p = td->td_proc;
1525 * When returning from sigsuspend, we want
1526 * the old mask to be restored after the
1527 * signal handler has finished. Thus, we
1528 * save it here and mark the sigacts structure
1532 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1533 SIGPROCMASK_PROC_LOCKED);
1534 td->td_pflags |= TDP_OLDMASK;
1537 * Process signals now. Otherwise, we can get spurious wakeup
1538 * due to signal entered process queue, but delivered to other
1539 * thread. But sigsuspend should return only on signal
1542 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1543 for (has_sig = 0; !has_sig;) {
1544 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1547 thread_suspend_check(0);
1548 mtx_lock(&p->p_sigacts->ps_mtx);
1549 while ((sig = cursig(td)) != 0) {
1550 KASSERT(sig >= 0, ("sig %d", sig));
1551 has_sig += postsig(sig);
1553 mtx_unlock(&p->p_sigacts->ps_mtx);
1556 * If PTRACE_SCE or PTRACE_SCX were set after
1557 * userspace entered the syscall, return spurious
1560 if ((p->p_ptevents & PTRACE_SYSCALL) != 0)
1564 td->td_errno = EINTR;
1565 td->td_pflags |= TDP_NERRNO;
1566 return (EJUSTRETURN);
1569 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1571 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1572 * convention: libc stub passes mask, not pointer, to save a copyin.
1574 #ifndef _SYS_SYSPROTO_H_
1575 struct osigsuspend_args {
1581 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1585 OSIG2SIG(uap->mask, mask);
1586 return (kern_sigsuspend(td, mask));
1588 #endif /* COMPAT_43 */
1590 #if defined(COMPAT_43)
1591 #ifndef _SYS_SYSPROTO_H_
1592 struct osigstack_args {
1593 struct sigstack *nss;
1594 struct sigstack *oss;
1599 osigstack(struct thread *td, struct osigstack_args *uap)
1601 struct sigstack nss, oss;
1604 if (uap->nss != NULL) {
1605 error = copyin(uap->nss, &nss, sizeof(nss));
1609 oss.ss_sp = td->td_sigstk.ss_sp;
1610 oss.ss_onstack = sigonstack(cpu_getstack(td));
1611 if (uap->nss != NULL) {
1612 td->td_sigstk.ss_sp = nss.ss_sp;
1613 td->td_sigstk.ss_size = 0;
1614 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1615 td->td_pflags |= TDP_ALTSTACK;
1617 if (uap->oss != NULL)
1618 error = copyout(&oss, uap->oss, sizeof(oss));
1622 #endif /* COMPAT_43 */
1624 #ifndef _SYS_SYSPROTO_H_
1625 struct sigaltstack_args {
1632 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1637 if (uap->ss != NULL) {
1638 error = copyin(uap->ss, &ss, sizeof(ss));
1642 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1643 (uap->oss != NULL) ? &oss : NULL);
1646 if (uap->oss != NULL)
1647 error = copyout(&oss, uap->oss, sizeof(stack_t));
1652 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1654 struct proc *p = td->td_proc;
1657 oonstack = sigonstack(cpu_getstack(td));
1660 *oss = td->td_sigstk;
1661 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1662 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1668 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1670 if (!(ss->ss_flags & SS_DISABLE)) {
1671 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1674 td->td_sigstk = *ss;
1675 td->td_pflags |= TDP_ALTSTACK;
1677 td->td_pflags &= ~TDP_ALTSTACK;
1683 struct killpg1_ctx {
1693 killpg1_sendsig(struct proc *p, bool notself, struct killpg1_ctx *arg)
1697 if (p->p_pid <= 1 || (p->p_flag & P_SYSTEM) != 0 ||
1698 (notself && p == arg->td->td_proc) || p->p_state == PRS_NEW)
1701 err = p_cansignal(arg->td, p, arg->sig);
1702 if (err == 0 && arg->sig != 0)
1703 pksignal(p, arg->sig, arg->ksi);
1709 else if (arg->ret == 0 && err != ESRCH && err != EPERM)
1714 * Common code for kill process group/broadcast kill.
1715 * cp is calling process.
1718 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1722 struct killpg1_ctx arg;
1734 sx_slock(&allproc_lock);
1735 FOREACH_PROC_IN_SYSTEM(p) {
1736 killpg1_sendsig(p, true, &arg);
1738 sx_sunlock(&allproc_lock);
1740 sx_slock(&proctree_lock);
1743 * zero pgid means send to my process group.
1745 pgrp = td->td_proc->p_pgrp;
1748 pgrp = pgfind(pgid);
1750 sx_sunlock(&proctree_lock);
1754 sx_sunlock(&proctree_lock);
1755 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1756 killpg1_sendsig(p, false, &arg);
1760 MPASS(arg.ret != 0 || arg.found || !arg.sent);
1761 if (arg.ret == 0 && !arg.sent)
1762 arg.ret = arg.found ? EPERM : ESRCH;
1766 #ifndef _SYS_SYSPROTO_H_
1774 sys_kill(struct thread *td, struct kill_args *uap)
1777 return (kern_kill(td, uap->pid, uap->signum));
1781 kern_kill(struct thread *td, pid_t pid, int signum)
1788 * A process in capability mode can send signals only to himself.
1789 * The main rationale behind this is that abort(3) is implemented as
1790 * kill(getpid(), SIGABRT).
1792 if (IN_CAPABILITY_MODE(td) && pid != td->td_proc->p_pid)
1795 AUDIT_ARG_SIGNUM(signum);
1797 if ((u_int)signum > _SIG_MAXSIG)
1800 ksiginfo_init(&ksi);
1801 ksi.ksi_signo = signum;
1802 ksi.ksi_code = SI_USER;
1803 ksi.ksi_pid = td->td_proc->p_pid;
1804 ksi.ksi_uid = td->td_ucred->cr_ruid;
1807 /* kill single process */
1808 if ((p = pfind_any(pid)) == NULL)
1810 AUDIT_ARG_PROCESS(p);
1811 error = p_cansignal(td, p, signum);
1812 if (error == 0 && signum)
1813 pksignal(p, signum, &ksi);
1818 case -1: /* broadcast signal */
1819 return (killpg1(td, signum, 0, 1, &ksi));
1820 case 0: /* signal own process group */
1821 return (killpg1(td, signum, 0, 0, &ksi));
1822 default: /* negative explicit process group */
1823 return (killpg1(td, signum, -pid, 0, &ksi));
1829 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1834 AUDIT_ARG_SIGNUM(uap->signum);
1835 AUDIT_ARG_FD(uap->fd);
1836 if ((u_int)uap->signum > _SIG_MAXSIG)
1839 error = procdesc_find(td, uap->fd, &cap_pdkill_rights, &p);
1842 AUDIT_ARG_PROCESS(p);
1843 error = p_cansignal(td, p, uap->signum);
1844 if (error == 0 && uap->signum)
1845 kern_psignal(p, uap->signum);
1850 #if defined(COMPAT_43)
1851 #ifndef _SYS_SYSPROTO_H_
1852 struct okillpg_args {
1859 okillpg(struct thread *td, struct okillpg_args *uap)
1863 AUDIT_ARG_SIGNUM(uap->signum);
1864 AUDIT_ARG_PID(uap->pgid);
1865 if ((u_int)uap->signum > _SIG_MAXSIG)
1868 ksiginfo_init(&ksi);
1869 ksi.ksi_signo = uap->signum;
1870 ksi.ksi_code = SI_USER;
1871 ksi.ksi_pid = td->td_proc->p_pid;
1872 ksi.ksi_uid = td->td_ucred->cr_ruid;
1873 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1875 #endif /* COMPAT_43 */
1877 #ifndef _SYS_SYSPROTO_H_
1878 struct sigqueue_args {
1881 /* union sigval */ void *value;
1885 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1889 sv.sival_ptr = uap->value;
1891 return (kern_sigqueue(td, uap->pid, uap->signum, &sv));
1895 kern_sigqueue(struct thread *td, pid_t pid, int signum, union sigval *value)
1901 if ((u_int)signum > _SIG_MAXSIG)
1905 * Specification says sigqueue can only send signal to
1911 if ((p = pfind_any(pid)) == NULL)
1913 error = p_cansignal(td, p, signum);
1914 if (error == 0 && signum != 0) {
1915 ksiginfo_init(&ksi);
1916 ksi.ksi_flags = KSI_SIGQ;
1917 ksi.ksi_signo = signum;
1918 ksi.ksi_code = SI_QUEUE;
1919 ksi.ksi_pid = td->td_proc->p_pid;
1920 ksi.ksi_uid = td->td_ucred->cr_ruid;
1921 ksi.ksi_value = *value;
1922 error = pksignal(p, ksi.ksi_signo, &ksi);
1929 * Send a signal to a process group.
1932 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1937 sx_slock(&proctree_lock);
1938 pgrp = pgfind(pgid);
1939 sx_sunlock(&proctree_lock);
1941 pgsignal(pgrp, sig, 0, ksi);
1948 * Send a signal to a process group. If checktty is 1,
1949 * limit to members which have a controlling terminal.
1952 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1957 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1958 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1960 if (p->p_state == PRS_NORMAL &&
1961 (checkctty == 0 || p->p_flag & P_CONTROLT))
1962 pksignal(p, sig, ksi);
1969 * Recalculate the signal mask and reset the signal disposition after
1970 * usermode frame for delivery is formed. Should be called after
1971 * mach-specific routine, because sysent->sv_sendsig() needs correct
1972 * ps_siginfo and signal mask.
1975 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1979 mtx_assert(&ps->ps_mtx, MA_OWNED);
1980 td->td_ru.ru_nsignals++;
1981 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1982 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1983 SIGADDSET(mask, sig);
1984 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1985 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1986 if (SIGISMEMBER(ps->ps_sigreset, sig))
1991 * Send a signal caused by a trap to the current thread. If it will be
1992 * caught immediately, deliver it with correct code. Otherwise, post it
1996 trapsignal(struct thread *td, ksiginfo_t *ksi)
2004 sig = ksi->ksi_signo;
2005 code = ksi->ksi_code;
2006 KASSERT(_SIG_VALID(sig), ("invalid signal"));
2010 mtx_lock(&ps->ps_mtx);
2011 sigmask = td->td_sigmask;
2012 if (td->td_sigblock_val != 0)
2013 SIGSETOR(sigmask, fastblock_mask);
2014 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
2015 !SIGISMEMBER(sigmask, sig)) {
2017 if (KTRPOINT(curthread, KTR_PSIG))
2018 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
2019 &td->td_sigmask, code);
2021 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
2022 ksi, &td->td_sigmask);
2023 postsig_done(sig, td, ps);
2024 mtx_unlock(&ps->ps_mtx);
2027 * Avoid a possible infinite loop if the thread
2028 * masking the signal or process is ignoring the
2031 if (kern_forcesigexit && (SIGISMEMBER(sigmask, sig) ||
2032 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
2033 SIGDELSET(td->td_sigmask, sig);
2034 SIGDELSET(ps->ps_sigcatch, sig);
2035 SIGDELSET(ps->ps_sigignore, sig);
2036 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2037 td->td_pflags &= ~TDP_SIGFASTBLOCK;
2038 td->td_sigblock_val = 0;
2040 mtx_unlock(&ps->ps_mtx);
2041 p->p_sig = sig; /* XXX to verify code */
2042 tdsendsignal(p, td, sig, ksi);
2047 static struct thread *
2048 sigtd(struct proc *p, int sig, bool fast_sigblock)
2050 struct thread *td, *signal_td;
2052 PROC_LOCK_ASSERT(p, MA_OWNED);
2053 MPASS(!fast_sigblock || p == curproc);
2056 * Check if current thread can handle the signal without
2057 * switching context to another thread.
2059 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig) &&
2060 (!fast_sigblock || curthread->td_sigblock_val == 0))
2063 FOREACH_THREAD_IN_PROC(p, td) {
2064 if (!SIGISMEMBER(td->td_sigmask, sig) && (!fast_sigblock ||
2065 td != curthread || td->td_sigblock_val == 0)) {
2070 if (signal_td == NULL)
2071 signal_td = FIRST_THREAD_IN_PROC(p);
2076 * Send the signal to the process. If the signal has an action, the action
2077 * is usually performed by the target process rather than the caller; we add
2078 * the signal to the set of pending signals for the process.
2081 * o When a stop signal is sent to a sleeping process that takes the
2082 * default action, the process is stopped without awakening it.
2083 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2084 * regardless of the signal action (eg, blocked or ignored).
2086 * Other ignored signals are discarded immediately.
2088 * NB: This function may be entered from the debugger via the "kill" DDB
2089 * command. There is little that can be done to mitigate the possibly messy
2090 * side effects of this unwise possibility.
2093 kern_psignal(struct proc *p, int sig)
2097 ksiginfo_init(&ksi);
2098 ksi.ksi_signo = sig;
2099 ksi.ksi_code = SI_KERNEL;
2100 (void) tdsendsignal(p, NULL, sig, &ksi);
2104 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2107 return (tdsendsignal(p, NULL, sig, ksi));
2110 /* Utility function for finding a thread to send signal event to. */
2112 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2116 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2117 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2129 tdsignal(struct thread *td, int sig)
2133 ksiginfo_init(&ksi);
2134 ksi.ksi_signo = sig;
2135 ksi.ksi_code = SI_KERNEL;
2136 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2140 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2143 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2147 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2150 sigqueue_t *sigqueue;
2157 MPASS(td == NULL || p == td->td_proc);
2158 PROC_LOCK_ASSERT(p, MA_OWNED);
2160 if (!_SIG_VALID(sig))
2161 panic("%s(): invalid signal %d", __func__, sig);
2163 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2166 * IEEE Std 1003.1-2001: return success when killing a zombie.
2168 if (p->p_state == PRS_ZOMBIE) {
2169 if (ksi && (ksi->ksi_flags & KSI_INS))
2170 ksiginfo_tryfree(ksi);
2175 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2176 prop = sigprop(sig);
2179 td = sigtd(p, sig, false);
2180 sigqueue = &p->p_sigqueue;
2182 sigqueue = &td->td_sigqueue;
2184 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2187 * If the signal is being ignored,
2188 * then we forget about it immediately.
2189 * (Note: we don't set SIGCONT in ps_sigignore,
2190 * and if it is set to SIG_IGN,
2191 * action will be SIG_DFL here.)
2193 mtx_lock(&ps->ps_mtx);
2194 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2195 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2197 mtx_unlock(&ps->ps_mtx);
2198 if (ksi && (ksi->ksi_flags & KSI_INS))
2199 ksiginfo_tryfree(ksi);
2202 if (SIGISMEMBER(td->td_sigmask, sig))
2204 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2208 if (SIGISMEMBER(ps->ps_sigintr, sig))
2212 mtx_unlock(&ps->ps_mtx);
2214 if (prop & SIGPROP_CONT)
2215 sigqueue_delete_stopmask_proc(p);
2216 else if (prop & SIGPROP_STOP) {
2218 * If sending a tty stop signal to a member of an orphaned
2219 * process group, discard the signal here if the action
2220 * is default; don't stop the process below if sleeping,
2221 * and don't clear any pending SIGCONT.
2223 if ((prop & SIGPROP_TTYSTOP) &&
2224 (p->p_pgrp->pg_jobc == 0) &&
2225 (action == SIG_DFL)) {
2226 if (ksi && (ksi->ksi_flags & KSI_INS))
2227 ksiginfo_tryfree(ksi);
2230 sigqueue_delete_proc(p, SIGCONT);
2231 if (p->p_flag & P_CONTINUED) {
2232 p->p_flag &= ~P_CONTINUED;
2233 PROC_LOCK(p->p_pptr);
2234 sigqueue_take(p->p_ksi);
2235 PROC_UNLOCK(p->p_pptr);
2239 ret = sigqueue_add(sigqueue, sig, ksi);
2244 * Defer further processing for signals which are held,
2245 * except that stopped processes must be continued by SIGCONT.
2247 if (action == SIG_HOLD &&
2248 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2251 /* SIGKILL: Remove procfs STOPEVENTs. */
2252 if (sig == SIGKILL) {
2253 /* from procfs_ioctl.c: PIOCBIC */
2255 /* from procfs_ioctl.c: PIOCCONT */
2262 * Some signals have a process-wide effect and a per-thread
2263 * component. Most processing occurs when the process next
2264 * tries to cross the user boundary, however there are some
2265 * times when processing needs to be done immediately, such as
2266 * waking up threads so that they can cross the user boundary.
2267 * We try to do the per-process part here.
2269 if (P_SHOULDSTOP(p)) {
2270 KASSERT(!(p->p_flag & P_WEXIT),
2271 ("signal to stopped but exiting process"));
2272 if (sig == SIGKILL) {
2274 * If traced process is already stopped,
2275 * then no further action is necessary.
2277 if (p->p_flag & P_TRACED)
2280 * SIGKILL sets process running.
2281 * It will die elsewhere.
2282 * All threads must be restarted.
2284 p->p_flag &= ~P_STOPPED_SIG;
2288 if (prop & SIGPROP_CONT) {
2290 * If traced process is already stopped,
2291 * then no further action is necessary.
2293 if (p->p_flag & P_TRACED)
2296 * If SIGCONT is default (or ignored), we continue the
2297 * process but don't leave the signal in sigqueue as
2298 * it has no further action. If SIGCONT is held, we
2299 * continue the process and leave the signal in
2300 * sigqueue. If the process catches SIGCONT, let it
2301 * handle the signal itself. If it isn't waiting on
2302 * an event, it goes back to run state.
2303 * Otherwise, process goes back to sleep state.
2305 p->p_flag &= ~P_STOPPED_SIG;
2307 if (p->p_numthreads == p->p_suspcount) {
2309 p->p_flag |= P_CONTINUED;
2310 p->p_xsig = SIGCONT;
2311 PROC_LOCK(p->p_pptr);
2312 childproc_continued(p);
2313 PROC_UNLOCK(p->p_pptr);
2316 if (action == SIG_DFL) {
2317 thread_unsuspend(p);
2319 sigqueue_delete(sigqueue, sig);
2322 if (action == SIG_CATCH) {
2324 * The process wants to catch it so it needs
2325 * to run at least one thread, but which one?
2331 * The signal is not ignored or caught.
2333 thread_unsuspend(p);
2338 if (prop & SIGPROP_STOP) {
2340 * If traced process is already stopped,
2341 * then no further action is necessary.
2343 if (p->p_flag & P_TRACED)
2346 * Already stopped, don't need to stop again
2347 * (If we did the shell could get confused).
2348 * Just make sure the signal STOP bit set.
2350 p->p_flag |= P_STOPPED_SIG;
2351 sigqueue_delete(sigqueue, sig);
2356 * All other kinds of signals:
2357 * If a thread is sleeping interruptibly, simulate a
2358 * wakeup so that when it is continued it will be made
2359 * runnable and can look at the signal. However, don't make
2360 * the PROCESS runnable, leave it stopped.
2361 * It may run a bit until it hits a thread_suspend_check().
2365 if (TD_CAN_ABORT(td))
2366 wakeup_swapper = sleepq_abort(td, intrval);
2372 * Mutexes are short lived. Threads waiting on them will
2373 * hit thread_suspend_check() soon.
2375 } else if (p->p_state == PRS_NORMAL) {
2376 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2377 tdsigwakeup(td, sig, action, intrval);
2381 MPASS(action == SIG_DFL);
2383 if (prop & SIGPROP_STOP) {
2384 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2386 p->p_flag |= P_STOPPED_SIG;
2389 wakeup_swapper = sig_suspend_threads(td, p, 1);
2390 if (p->p_numthreads == p->p_suspcount) {
2392 * only thread sending signal to another
2393 * process can reach here, if thread is sending
2394 * signal to its process, because thread does
2395 * not suspend itself here, p_numthreads
2396 * should never be equal to p_suspcount.
2400 sigqueue_delete_proc(p, p->p_xsig);
2406 /* Not in "NORMAL" state. discard the signal. */
2407 sigqueue_delete(sigqueue, sig);
2412 * The process is not stopped so we need to apply the signal to all the
2416 tdsigwakeup(td, sig, action, intrval);
2418 thread_unsuspend(p);
2421 /* If we jump here, proc slock should not be owned. */
2422 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2430 * The force of a signal has been directed against a single
2431 * thread. We need to see what we can do about knocking it
2432 * out of any sleep it may be in etc.
2435 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2437 struct proc *p = td->td_proc;
2438 int prop, wakeup_swapper;
2440 PROC_LOCK_ASSERT(p, MA_OWNED);
2441 prop = sigprop(sig);
2446 * Bring the priority of a thread up if we want it to get
2447 * killed in this lifetime. Be careful to avoid bumping the
2448 * priority of the idle thread, since we still allow to signal
2451 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2452 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2453 sched_prio(td, PUSER);
2454 if (TD_ON_SLEEPQ(td)) {
2456 * If thread is sleeping uninterruptibly
2457 * we can't interrupt the sleep... the signal will
2458 * be noticed when the process returns through
2459 * trap() or syscall().
2461 if ((td->td_flags & TDF_SINTR) == 0)
2464 * If SIGCONT is default (or ignored) and process is
2465 * asleep, we are finished; the process should not
2468 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2471 sigqueue_delete(&p->p_sigqueue, sig);
2473 * It may be on either list in this state.
2474 * Remove from both for now.
2476 sigqueue_delete(&td->td_sigqueue, sig);
2481 * Don't awaken a sleeping thread for SIGSTOP if the
2482 * STOP signal is deferred.
2484 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2485 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2489 * Give low priority threads a better chance to run.
2491 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2492 sched_prio(td, PUSER);
2494 wakeup_swapper = sleepq_abort(td, intrval);
2502 * Other states do nothing with the signal immediately,
2503 * other than kicking ourselves if we are running.
2504 * It will either never be noticed, or noticed very soon.
2507 if (TD_IS_RUNNING(td) && td != curthread)
2517 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2522 PROC_LOCK_ASSERT(p, MA_OWNED);
2523 PROC_SLOCK_ASSERT(p, MA_OWNED);
2524 MPASS(sending || td == curthread);
2527 FOREACH_THREAD_IN_PROC(p, td2) {
2529 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2530 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2531 (td2->td_flags & TDF_SINTR)) {
2532 if (td2->td_flags & TDF_SBDRY) {
2534 * Once a thread is asleep with
2535 * TDF_SBDRY and without TDF_SERESTART
2536 * or TDF_SEINTR set, it should never
2537 * become suspended due to this check.
2539 KASSERT(!TD_IS_SUSPENDED(td2),
2540 ("thread with deferred stops suspended"));
2541 if (TD_SBDRY_INTR(td2)) {
2542 wakeup_swapper |= sleepq_abort(td2,
2543 TD_SBDRY_ERRNO(td2));
2546 } else if (!TD_IS_SUSPENDED(td2))
2547 thread_suspend_one(td2);
2548 } else if (!TD_IS_SUSPENDED(td2)) {
2549 if (sending || td != td2)
2550 td2->td_flags |= TDF_ASTPENDING;
2552 if (TD_IS_RUNNING(td2) && td2 != td)
2553 forward_signal(td2);
2558 return (wakeup_swapper);
2562 * Stop the process for an event deemed interesting to the debugger. If si is
2563 * non-NULL, this is a signal exchange; the new signal requested by the
2564 * debugger will be returned for handling. If si is NULL, this is some other
2565 * type of interesting event. The debugger may request a signal be delivered in
2566 * that case as well, however it will be deferred until it can be handled.
2569 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2571 struct proc *p = td->td_proc;
2575 PROC_LOCK_ASSERT(p, MA_OWNED);
2576 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2577 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2578 &p->p_mtx.lock_object, "Stopping for traced signal");
2582 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2583 td->td_dbgflags |= TDB_XSIG;
2584 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2585 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2587 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2590 * Ensure that, if we've been PT_KILLed, the
2591 * exit status reflects that. Another thread
2592 * may also be in ptracestop(), having just
2593 * received the SIGKILL, but this thread was
2594 * unsuspended first.
2596 td->td_dbgflags &= ~TDB_XSIG;
2597 td->td_xsig = SIGKILL;
2601 if (p->p_flag & P_SINGLE_EXIT &&
2602 !(td->td_dbgflags & TDB_EXIT)) {
2604 * Ignore ptrace stops except for thread exit
2605 * events when the process exits.
2607 td->td_dbgflags &= ~TDB_XSIG;
2613 * Make wait(2) work. Ensure that right after the
2614 * attach, the thread which was decided to become the
2615 * leader of attach gets reported to the waiter.
2616 * Otherwise, just avoid overwriting another thread's
2617 * assignment to p_xthread. If another thread has
2618 * already set p_xthread, the current thread will get
2619 * a chance to report itself upon the next iteration.
2621 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2622 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2623 p->p_xthread == NULL)) {
2628 * If we are on sleepqueue already,
2629 * let sleepqueue code decide if it
2630 * needs to go sleep after attach.
2632 if (td->td_wchan == NULL)
2633 td->td_dbgflags &= ~TDB_FSTP;
2635 p->p_flag2 &= ~P2_PTRACE_FSTP;
2636 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2637 sig_suspend_threads(td, p, 0);
2639 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2640 td->td_dbgflags &= ~TDB_STOPATFORK;
2643 thread_suspend_switch(td, p);
2644 if (p->p_xthread == td)
2645 p->p_xthread = NULL;
2646 if (!(p->p_flag & P_TRACED))
2648 if (td->td_dbgflags & TDB_SUSPEND) {
2649 if (p->p_flag & P_SINGLE_EXIT)
2657 if (si != NULL && sig == td->td_xsig) {
2658 /* Parent wants us to take the original signal unchanged. */
2659 si->ksi_flags |= KSI_HEAD;
2660 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2662 } else if (td->td_xsig != 0) {
2664 * If parent wants us to take a new signal, then it will leave
2665 * it in td->td_xsig; otherwise we just look for signals again.
2667 ksiginfo_init(&ksi);
2668 ksi.ksi_signo = td->td_xsig;
2669 ksi.ksi_flags |= KSI_PTRACE;
2670 td2 = sigtd(p, td->td_xsig, false);
2671 tdsendsignal(p, td2, td->td_xsig, &ksi);
2676 return (td->td_xsig);
2680 reschedule_signals(struct proc *p, sigset_t block, int flags)
2685 bool fastblk, pslocked;
2687 PROC_LOCK_ASSERT(p, MA_OWNED);
2689 pslocked = (flags & SIGPROCMASK_PS_LOCKED) != 0;
2690 mtx_assert(&ps->ps_mtx, pslocked ? MA_OWNED : MA_NOTOWNED);
2691 if (SIGISEMPTY(p->p_siglist))
2693 SIGSETAND(block, p->p_siglist);
2694 fastblk = (flags & SIGPROCMASK_FASTBLK) != 0;
2695 while ((sig = sig_ffs(&block)) != 0) {
2696 SIGDELSET(block, sig);
2697 td = sigtd(p, sig, fastblk);
2700 * If sigtd() selected us despite sigfastblock is
2701 * blocking, do not activate AST or wake us, to avoid
2702 * loop in AST handler.
2704 if (fastblk && td == curthread)
2709 mtx_lock(&ps->ps_mtx);
2710 if (p->p_flag & P_TRACED ||
2711 (SIGISMEMBER(ps->ps_sigcatch, sig) &&
2712 !SIGISMEMBER(td->td_sigmask, sig))) {
2713 tdsigwakeup(td, sig, SIG_CATCH,
2714 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2718 mtx_unlock(&ps->ps_mtx);
2723 tdsigcleanup(struct thread *td)
2729 PROC_LOCK_ASSERT(p, MA_OWNED);
2731 sigqueue_flush(&td->td_sigqueue);
2732 if (p->p_numthreads == 1)
2736 * Since we cannot handle signals, notify signal post code
2737 * about this by filling the sigmask.
2739 * Also, if needed, wake up thread(s) that do not block the
2740 * same signals as the exiting thread, since the thread might
2741 * have been selected for delivery and woken up.
2743 SIGFILLSET(unblocked);
2744 SIGSETNAND(unblocked, td->td_sigmask);
2745 SIGFILLSET(td->td_sigmask);
2746 reschedule_signals(p, unblocked, 0);
2751 sigdeferstop_curr_flags(int cflags)
2754 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2755 (cflags & TDF_SBDRY) != 0);
2756 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2760 * Defer the delivery of SIGSTOP for the current thread, according to
2761 * the requested mode. Returns previous flags, which must be restored
2762 * by sigallowstop().
2764 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2765 * cleared by the current thread, which allow the lock-less read-only
2769 sigdeferstop_impl(int mode)
2775 cflags = sigdeferstop_curr_flags(td->td_flags);
2777 case SIGDEFERSTOP_NOP:
2780 case SIGDEFERSTOP_OFF:
2783 case SIGDEFERSTOP_SILENT:
2784 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2786 case SIGDEFERSTOP_EINTR:
2787 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2789 case SIGDEFERSTOP_ERESTART:
2790 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2793 panic("sigdeferstop: invalid mode %x", mode);
2796 if (cflags == nflags)
2797 return (SIGDEFERSTOP_VAL_NCHG);
2799 td->td_flags = (td->td_flags & ~cflags) | nflags;
2805 * Restores the STOP handling mode, typically permitting the delivery
2806 * of SIGSTOP for the current thread. This does not immediately
2807 * suspend if a stop was posted. Instead, the thread will suspend
2808 * either via ast() or a subsequent interruptible sleep.
2811 sigallowstop_impl(int prev)
2816 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2817 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2818 ("sigallowstop: incorrect previous mode %x", prev));
2820 cflags = sigdeferstop_curr_flags(td->td_flags);
2821 if (cflags != prev) {
2823 td->td_flags = (td->td_flags & ~cflags) | prev;
2829 * If the current process has received a signal (should be caught or cause
2830 * termination, should interrupt current syscall), return the signal number.
2831 * Stop signals with default action are processed immediately, then cleared;
2832 * they aren't returned. This is checked after each entry to the system for
2833 * a syscall or trap (though this can usually be done without calling issignal
2834 * by checking the pending signal masks in cursig.) The normal call
2837 * while (sig = cursig(curthread))
2841 issignal(struct thread *td)
2845 struct sigqueue *queue;
2846 sigset_t sigpending;
2848 int prop, sig, traced;
2852 mtx_assert(&ps->ps_mtx, MA_OWNED);
2853 PROC_LOCK_ASSERT(p, MA_OWNED);
2855 traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2857 sigpending = td->td_sigqueue.sq_signals;
2858 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2859 SIGSETNAND(sigpending, td->td_sigmask);
2861 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
2862 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2863 SIG_STOPSIGMASK(sigpending);
2864 if (SIGISEMPTY(sigpending)) /* no signal to send */
2868 * Do fast sigblock if requested by usermode. Since
2869 * we do know that there was a signal pending at this
2870 * point, set the FAST_SIGBLOCK_PEND as indicator for
2871 * usermode to perform a dummy call to
2872 * FAST_SIGBLOCK_UNBLOCK, which causes immediate
2873 * delivery of postponed pending signal.
2875 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
2876 if (td->td_sigblock_val != 0)
2877 SIGSETNAND(sigpending, fastblock_mask);
2878 if (SIGISEMPTY(sigpending)) {
2879 td->td_pflags |= TDP_SIGFASTPENDING;
2884 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2885 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2886 SIGISMEMBER(sigpending, SIGSTOP)) {
2888 * If debugger just attached, always consume
2889 * SIGSTOP from ptrace(PT_ATTACH) first, to
2890 * execute the debugger attach ritual in
2894 td->td_dbgflags |= TDB_FSTP;
2896 sig = sig_ffs(&sigpending);
2899 if (p->p_stops & S_SIG) {
2900 mtx_unlock(&ps->ps_mtx);
2901 stopevent(p, S_SIG, sig);
2902 mtx_lock(&ps->ps_mtx);
2906 * We should see pending but ignored signals
2907 * only if P_TRACED was on when they were posted.
2909 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2910 sigqueue_delete(&td->td_sigqueue, sig);
2911 sigqueue_delete(&p->p_sigqueue, sig);
2914 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2916 * If traced, always stop.
2917 * Remove old signal from queue before the stop.
2918 * XXX shrug off debugger, it causes siginfo to
2921 queue = &td->td_sigqueue;
2922 ksiginfo_init(&ksi);
2923 if (sigqueue_get(queue, sig, &ksi) == 0) {
2924 queue = &p->p_sigqueue;
2925 sigqueue_get(queue, sig, &ksi);
2927 td->td_si = ksi.ksi_info;
2929 mtx_unlock(&ps->ps_mtx);
2930 sig = ptracestop(td, sig, &ksi);
2931 mtx_lock(&ps->ps_mtx);
2933 td->td_si.si_signo = 0;
2936 * Keep looking if the debugger discarded or
2937 * replaced the signal.
2943 * If the signal became masked, re-queue it.
2945 if (SIGISMEMBER(td->td_sigmask, sig)) {
2946 ksi.ksi_flags |= KSI_HEAD;
2947 sigqueue_add(&p->p_sigqueue, sig, &ksi);
2952 * If the traced bit got turned off, requeue
2953 * the signal and go back up to the top to
2954 * rescan signals. This ensures that p_sig*
2955 * and p_sigact are consistent.
2957 if ((p->p_flag & P_TRACED) == 0) {
2958 ksi.ksi_flags |= KSI_HEAD;
2959 sigqueue_add(queue, sig, &ksi);
2964 prop = sigprop(sig);
2967 * Decide whether the signal should be returned.
2968 * Return the signal's number, or fall through
2969 * to clear it from the pending mask.
2971 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2973 case (intptr_t)SIG_DFL:
2975 * Don't take default actions on system processes.
2977 if (p->p_pid <= 1) {
2980 * Are you sure you want to ignore SIGSEGV
2983 printf("Process (pid %lu) got signal %d\n",
2984 (u_long)p->p_pid, sig);
2986 break; /* == ignore */
2989 * If there is a pending stop signal to process with
2990 * default action, stop here, then clear the signal.
2991 * Traced or exiting processes should ignore stops.
2992 * Additionally, a member of an orphaned process group
2993 * should ignore tty stops.
2995 if (prop & SIGPROP_STOP) {
2997 (P_TRACED | P_WEXIT | P_SINGLE_EXIT) ||
2998 (p->p_pgrp->pg_jobc == 0 &&
2999 prop & SIGPROP_TTYSTOP))
3000 break; /* == ignore */
3001 if (TD_SBDRY_INTR(td)) {
3002 KASSERT((td->td_flags & TDF_SBDRY) != 0,
3003 ("lost TDF_SBDRY"));
3006 mtx_unlock(&ps->ps_mtx);
3007 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
3008 &p->p_mtx.lock_object, "Catching SIGSTOP");
3009 sigqueue_delete(&td->td_sigqueue, sig);
3010 sigqueue_delete(&p->p_sigqueue, sig);
3011 p->p_flag |= P_STOPPED_SIG;
3014 sig_suspend_threads(td, p, 0);
3015 thread_suspend_switch(td, p);
3017 mtx_lock(&ps->ps_mtx);
3019 } else if (prop & SIGPROP_IGNORE) {
3021 * Except for SIGCONT, shouldn't get here.
3022 * Default action is to ignore; drop it.
3024 break; /* == ignore */
3029 case (intptr_t)SIG_IGN:
3031 * Masking above should prevent us ever trying
3032 * to take action on an ignored signal other
3033 * than SIGCONT, unless process is traced.
3035 if ((prop & SIGPROP_CONT) == 0 &&
3036 (p->p_flag & P_TRACED) == 0)
3037 printf("issignal\n");
3038 break; /* == ignore */
3042 * This signal has an action, let
3043 * postsig() process it.
3047 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
3048 sigqueue_delete(&p->p_sigqueue, sig);
3055 thread_stopped(struct proc *p)
3059 PROC_LOCK_ASSERT(p, MA_OWNED);
3060 PROC_SLOCK_ASSERT(p, MA_OWNED);
3064 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
3066 p->p_flag &= ~P_WAITED;
3067 PROC_LOCK(p->p_pptr);
3068 childproc_stopped(p, (p->p_flag & P_TRACED) ?
3069 CLD_TRAPPED : CLD_STOPPED);
3070 PROC_UNLOCK(p->p_pptr);
3076 * Take the action for the specified signal
3077 * from the current set of pending signals.
3087 sigset_t returnmask;
3089 KASSERT(sig != 0, ("postsig"));
3093 PROC_LOCK_ASSERT(p, MA_OWNED);
3095 mtx_assert(&ps->ps_mtx, MA_OWNED);
3096 ksiginfo_init(&ksi);
3097 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
3098 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
3100 ksi.ksi_signo = sig;
3101 if (ksi.ksi_code == SI_TIMER)
3102 itimer_accept(p, ksi.ksi_timerid, &ksi);
3103 action = ps->ps_sigact[_SIG_IDX(sig)];
3105 if (KTRPOINT(td, KTR_PSIG))
3106 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
3107 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
3109 if ((p->p_stops & S_SIG) != 0) {
3110 mtx_unlock(&ps->ps_mtx);
3111 stopevent(p, S_SIG, sig);
3112 mtx_lock(&ps->ps_mtx);
3115 if (action == SIG_DFL) {
3117 * Default action, where the default is to kill
3118 * the process. (Other cases were ignored above.)
3120 mtx_unlock(&ps->ps_mtx);
3121 proc_td_siginfo_capture(td, &ksi.ksi_info);
3126 * If we get here, the signal must be caught.
3128 KASSERT(action != SIG_IGN, ("postsig action %p", action));
3129 KASSERT(!SIGISMEMBER(td->td_sigmask, sig),
3130 ("postsig action: blocked sig %d", sig));
3133 * Set the new mask value and also defer further
3134 * occurrences of this signal.
3136 * Special case: user has done a sigsuspend. Here the
3137 * current mask is not of interest, but rather the
3138 * mask from before the sigsuspend is what we want
3139 * restored after the signal processing is completed.
3141 if (td->td_pflags & TDP_OLDMASK) {
3142 returnmask = td->td_oldsigmask;
3143 td->td_pflags &= ~TDP_OLDMASK;
3145 returnmask = td->td_sigmask;
3147 if (p->p_sig == sig) {
3150 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3151 postsig_done(sig, td, ps);
3157 proc_wkilled(struct proc *p)
3160 PROC_LOCK_ASSERT(p, MA_OWNED);
3161 if ((p->p_flag & P_WKILLED) == 0) {
3162 p->p_flag |= P_WKILLED;
3164 * Notify swapper that there is a process to swap in.
3165 * The notification is racy, at worst it would take 10
3166 * seconds for the swapper process to notice.
3168 if ((p->p_flag & (P_INMEM | P_SWAPPINGIN)) == 0)
3174 * Kill the current process for stated reason.
3177 killproc(struct proc *p, char *why)
3180 PROC_LOCK_ASSERT(p, MA_OWNED);
3181 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3183 log(LOG_ERR, "pid %d (%s), jid %d, uid %d, was killed: %s\n",
3184 p->p_pid, p->p_comm, p->p_ucred->cr_prison->pr_id,
3185 p->p_ucred->cr_uid, why);
3187 kern_psignal(p, SIGKILL);
3191 * Force the current process to exit with the specified signal, dumping core
3192 * if appropriate. We bypass the normal tests for masked and caught signals,
3193 * allowing unrecoverable failures to terminate the process without changing
3194 * signal state. Mark the accounting record with the signal termination.
3195 * If dumping core, save the signal number for the debugger. Calls exit and
3199 sigexit(struct thread *td, int sig)
3201 struct proc *p = td->td_proc;
3203 PROC_LOCK_ASSERT(p, MA_OWNED);
3204 p->p_acflag |= AXSIG;
3206 * We must be single-threading to generate a core dump. This
3207 * ensures that the registers in the core file are up-to-date.
3208 * Also, the ELF dump handler assumes that the thread list doesn't
3209 * change out from under it.
3211 * XXX If another thread attempts to single-thread before us
3212 * (e.g. via fork()), we won't get a dump at all.
3214 if ((sigprop(sig) & SIGPROP_CORE) &&
3215 thread_single(p, SINGLE_NO_EXIT) == 0) {
3218 * Log signals which would cause core dumps
3219 * (Log as LOG_INFO to appease those who don't want
3221 * XXX : Todo, as well as euid, write out ruid too
3222 * Note that coredump() drops proc lock.
3224 if (coredump(td) == 0)
3226 if (kern_logsigexit)
3228 "pid %d (%s), jid %d, uid %d: exited on "
3229 "signal %d%s\n", p->p_pid, p->p_comm,
3230 p->p_ucred->cr_prison->pr_id,
3231 td->td_ucred->cr_uid,
3233 sig & WCOREFLAG ? " (core dumped)" : "");
3241 * Send queued SIGCHLD to parent when child process's state
3245 sigparent(struct proc *p, int reason, int status)
3247 PROC_LOCK_ASSERT(p, MA_OWNED);
3248 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3250 if (p->p_ksi != NULL) {
3251 p->p_ksi->ksi_signo = SIGCHLD;
3252 p->p_ksi->ksi_code = reason;
3253 p->p_ksi->ksi_status = status;
3254 p->p_ksi->ksi_pid = p->p_pid;
3255 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3256 if (KSI_ONQ(p->p_ksi))
3259 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3263 childproc_jobstate(struct proc *p, int reason, int sig)
3267 PROC_LOCK_ASSERT(p, MA_OWNED);
3268 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3271 * Wake up parent sleeping in kern_wait(), also send
3272 * SIGCHLD to parent, but SIGCHLD does not guarantee
3273 * that parent will awake, because parent may masked
3276 p->p_pptr->p_flag |= P_STATCHILD;
3279 ps = p->p_pptr->p_sigacts;
3280 mtx_lock(&ps->ps_mtx);
3281 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3282 mtx_unlock(&ps->ps_mtx);
3283 sigparent(p, reason, sig);
3285 mtx_unlock(&ps->ps_mtx);
3289 childproc_stopped(struct proc *p, int reason)
3292 childproc_jobstate(p, reason, p->p_xsig);
3296 childproc_continued(struct proc *p)
3298 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3302 childproc_exited(struct proc *p)
3306 if (WCOREDUMP(p->p_xsig)) {
3307 reason = CLD_DUMPED;
3308 status = WTERMSIG(p->p_xsig);
3309 } else if (WIFSIGNALED(p->p_xsig)) {
3310 reason = CLD_KILLED;
3311 status = WTERMSIG(p->p_xsig);
3313 reason = CLD_EXITED;
3314 status = p->p_xexit;
3317 * XXX avoid calling wakeup(p->p_pptr), the work is
3320 sigparent(p, reason, status);
3323 #define MAX_NUM_CORE_FILES 100000
3324 #ifndef NUM_CORE_FILES
3325 #define NUM_CORE_FILES 5
3327 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3328 static int num_cores = NUM_CORE_FILES;
3331 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3336 new_val = num_cores;
3337 error = sysctl_handle_int(oidp, &new_val, 0, req);
3338 if (error != 0 || req->newptr == NULL)
3340 if (new_val > MAX_NUM_CORE_FILES)
3341 new_val = MAX_NUM_CORE_FILES;
3344 num_cores = new_val;
3347 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3348 0, sizeof(int), sysctl_debug_num_cores_check, "I",
3349 "Maximum number of generated process corefiles while using index format");
3351 #define GZIP_SUFFIX ".gz"
3352 #define ZSTD_SUFFIX ".zst"
3354 int compress_user_cores = 0;
3357 sysctl_compress_user_cores(SYSCTL_HANDLER_ARGS)
3361 val = compress_user_cores;
3362 error = sysctl_handle_int(oidp, &val, 0, req);
3363 if (error != 0 || req->newptr == NULL)
3365 if (val != 0 && !compressor_avail(val))
3367 compress_user_cores = val;
3370 SYSCTL_PROC(_kern, OID_AUTO, compress_user_cores, CTLTYPE_INT | CTLFLAG_RWTUN,
3371 0, sizeof(int), sysctl_compress_user_cores, "I",
3372 "Enable compression of user corefiles ("
3373 __XSTRING(COMPRESS_GZIP) " = gzip, "
3374 __XSTRING(COMPRESS_ZSTD) " = zstd)");
3376 int compress_user_cores_level = 6;
3377 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_level, CTLFLAG_RWTUN,
3378 &compress_user_cores_level, 0,
3379 "Corefile compression level");
3382 * Protect the access to corefilename[] by allproc_lock.
3384 #define corefilename_lock allproc_lock
3386 static char corefilename[MAXPATHLEN] = {"%N.core"};
3387 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3390 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3394 sx_xlock(&corefilename_lock);
3395 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3397 sx_xunlock(&corefilename_lock);
3401 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3402 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3403 "Process corefile name format string");
3406 vnode_close_locked(struct thread *td, struct vnode *vp)
3410 vn_close(vp, FWRITE, td->td_ucred, td);
3414 * If the core format has a %I in it, then we need to check
3415 * for existing corefiles before defining a name.
3416 * To do this we iterate over 0..ncores to find a
3417 * non-existing core file name to use. If all core files are
3418 * already used we choose the oldest one.
3421 corefile_open_last(struct thread *td, char *name, int indexpos,
3422 int indexlen, int ncores, struct vnode **vpp)
3424 struct vnode *oldvp, *nextvp, *vp;
3426 struct nameidata nd;
3427 int error, i, flags, oflags, cmode;
3429 struct timespec lasttime;
3431 nextvp = oldvp = NULL;
3432 cmode = S_IRUSR | S_IWUSR;
3433 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3434 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3436 for (i = 0; i < ncores; i++) {
3437 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3439 ch = name[indexpos + indexlen];
3440 (void)snprintf(name + indexpos, indexlen + 1, "%.*u", indexlen,
3442 name[indexpos + indexlen] = ch;
3444 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3445 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3451 NDFREE(&nd, NDF_ONLY_PNBUF);
3452 if ((flags & O_CREAT) == O_CREAT) {
3457 error = VOP_GETATTR(vp, &vattr, td->td_ucred);
3459 vnode_close_locked(td, vp);
3463 if (oldvp == NULL ||
3464 lasttime.tv_sec > vattr.va_mtime.tv_sec ||
3465 (lasttime.tv_sec == vattr.va_mtime.tv_sec &&
3466 lasttime.tv_nsec >= vattr.va_mtime.tv_nsec)) {
3468 vnode_close_locked(td, oldvp);
3470 lasttime = vattr.va_mtime;
3472 vnode_close_locked(td, vp);
3476 if (oldvp != NULL) {
3477 if (nextvp == NULL) {
3478 if ((td->td_proc->p_flag & P_SUGID) != 0) {
3480 vnode_close_locked(td, oldvp);
3485 vnode_close_locked(td, oldvp);
3490 vnode_close_locked(td, oldvp);
3499 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3500 * Expand the name described in corefilename, using name, uid, and pid
3501 * and open/create core file.
3502 * corefilename is a printf-like string, with three format specifiers:
3503 * %N name of process ("name")
3504 * %P process id (pid)
3506 * For example, "%N.core" is the default; they can be disabled completely
3507 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3508 * This is controlled by the sysctl variable kern.corefile (see above).
3511 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3512 int compress, int signum, struct vnode **vpp, char **namep)
3515 struct nameidata nd;
3517 char *hostname, *name;
3518 int cmode, error, flags, i, indexpos, indexlen, oflags, ncores;
3521 format = corefilename;
3522 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3526 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3527 sx_slock(&corefilename_lock);
3528 for (i = 0; format[i] != '\0'; i++) {
3529 switch (format[i]) {
3530 case '%': /* Format character */
3532 switch (format[i]) {
3534 sbuf_putc(&sb, '%');
3536 case 'H': /* hostname */
3537 if (hostname == NULL) {
3538 hostname = malloc(MAXHOSTNAMELEN,
3541 getcredhostname(td->td_ucred, hostname,
3543 sbuf_printf(&sb, "%s", hostname);
3545 case 'I': /* autoincrementing index */
3546 if (indexpos != -1) {
3547 sbuf_printf(&sb, "%%I");
3551 indexpos = sbuf_len(&sb);
3552 sbuf_printf(&sb, "%u", ncores - 1);
3553 indexlen = sbuf_len(&sb) - indexpos;
3555 case 'N': /* process name */
3556 sbuf_printf(&sb, "%s", comm);
3558 case 'P': /* process id */
3559 sbuf_printf(&sb, "%u", pid);
3561 case 'S': /* signal number */
3562 sbuf_printf(&sb, "%i", signum);
3564 case 'U': /* user id */
3565 sbuf_printf(&sb, "%u", uid);
3569 "Unknown format character %c in "
3570 "corename `%s'\n", format[i], format);
3575 sbuf_putc(&sb, format[i]);
3579 sx_sunlock(&corefilename_lock);
3580 free(hostname, M_TEMP);
3581 if (compress == COMPRESS_GZIP)
3582 sbuf_printf(&sb, GZIP_SUFFIX);
3583 else if (compress == COMPRESS_ZSTD)
3584 sbuf_printf(&sb, ZSTD_SUFFIX);
3585 if (sbuf_error(&sb) != 0) {
3586 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3587 "long\n", (long)pid, comm, (u_long)uid);
3595 if (indexpos != -1) {
3596 error = corefile_open_last(td, name, indexpos, indexlen, ncores,
3600 "pid %d (%s), uid (%u): Path `%s' failed "
3601 "on initial open test, error = %d\n",
3602 pid, comm, uid, name, error);
3605 cmode = S_IRUSR | S_IWUSR;
3606 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3607 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3608 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3609 if ((td->td_proc->p_flag & P_SUGID) != 0)
3612 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3613 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred,
3617 NDFREE(&nd, NDF_ONLY_PNBUF);
3623 audit_proc_coredump(td, name, error);
3633 * Dump a process' core. The main routine does some
3634 * policy checking, and creates the name of the coredump;
3635 * then it passes on a vnode and a size limit to the process-specific
3636 * coredump routine if there is one; if there _is not_ one, it returns
3637 * ENOSYS; otherwise it returns the error from the process-specific routine.
3641 coredump(struct thread *td)
3643 struct proc *p = td->td_proc;
3644 struct ucred *cred = td->td_ucred;
3648 size_t fullpathsize;
3649 int error, error1, locked;
3650 char *name; /* name of corefile */
3653 char *fullpath, *freepath = NULL;
3656 PROC_LOCK_ASSERT(p, MA_OWNED);
3657 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3658 _STOPEVENT(p, S_CORE, 0);
3660 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3661 (p->p_flag2 & P2_NOTRACE) != 0) {
3667 * Note that the bulk of limit checking is done after
3668 * the corefile is created. The exception is if the limit
3669 * for corefiles is 0, in which case we don't bother
3670 * creating the corefile at all. This layout means that
3671 * a corefile is truncated instead of not being created,
3672 * if it is larger than the limit.
3674 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3675 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3681 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3682 compress_user_cores, p->p_sig, &vp, &name);
3687 * Don't dump to non-regular files or files with links.
3688 * Do not dump into system files. Effective user must own the corefile.
3690 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3691 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0 ||
3692 vattr.va_uid != cred->cr_uid) {
3700 /* Postpone other writers, including core dumps of other processes. */
3701 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3703 lf.l_whence = SEEK_SET;
3706 lf.l_type = F_WRLCK;
3707 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3711 if (set_core_nodump_flag)
3712 vattr.va_flags = UF_NODUMP;
3713 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3714 VOP_SETATTR(vp, &vattr, cred);
3717 p->p_acflag |= ACORE;
3720 if (p->p_sysent->sv_coredump != NULL) {
3721 error = p->p_sysent->sv_coredump(td, vp, limit, 0);
3727 lf.l_type = F_UNLCK;
3728 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3730 vn_rangelock_unlock(vp, rl_cookie);
3733 * Notify the userland helper that a process triggered a core dump.
3734 * This allows the helper to run an automated debugging session.
3736 if (error != 0 || coredump_devctl == 0)
3738 sb = sbuf_new_auto();
3739 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3741 sbuf_printf(sb, "comm=\"");
3742 devctl_safe_quote_sb(sb, fullpath);
3743 free(freepath, M_TEMP);
3744 sbuf_printf(sb, "\" core=\"");
3747 * We can't lookup core file vp directly. When we're replacing a core, and
3748 * other random times, we flush the name cache, so it will fail. Instead,
3749 * if the path of the core is relative, add the current dir in front if it.
3751 if (name[0] != '/') {
3752 fullpathsize = MAXPATHLEN;
3753 freepath = malloc(fullpathsize, M_TEMP, M_WAITOK);
3754 if (vn_getcwd(td, freepath, &fullpath, &fullpathsize) != 0) {
3755 free(freepath, M_TEMP);
3758 devctl_safe_quote_sb(sb, fullpath);
3759 free(freepath, M_TEMP);
3762 devctl_safe_quote_sb(sb, name);
3763 sbuf_printf(sb, "\"");
3764 if (sbuf_finish(sb) == 0)
3765 devctl_notify("kernel", "signal", "coredump", sbuf_data(sb));
3769 error1 = vn_close(vp, FWRITE, cred, td);
3773 audit_proc_coredump(td, name, error);
3780 * Nonexistent system call-- signal process (may want to handle it). Flag
3781 * error in case process won't see signal immediately (blocked or ignored).
3783 #ifndef _SYS_SYSPROTO_H_
3790 nosys(struct thread *td, struct nosys_args *args)
3797 tdsignal(td, SIGSYS);
3799 if (kern_lognosys == 1 || kern_lognosys == 3) {
3800 uprintf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3803 if (kern_lognosys == 2 || kern_lognosys == 3) {
3804 printf("pid %d comm %s: nosys %d\n", p->p_pid, p->p_comm,
3811 * Send a SIGIO or SIGURG signal to a process or process group using stored
3812 * credentials rather than those of the current process.
3815 pgsigio(struct sigio **sigiop, int sig, int checkctty)
3818 struct sigio *sigio;
3820 ksiginfo_init(&ksi);
3821 ksi.ksi_signo = sig;
3822 ksi.ksi_code = SI_KERNEL;
3826 if (sigio == NULL) {
3830 if (sigio->sio_pgid > 0) {
3831 PROC_LOCK(sigio->sio_proc);
3832 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3833 kern_psignal(sigio->sio_proc, sig);
3834 PROC_UNLOCK(sigio->sio_proc);
3835 } else if (sigio->sio_pgid < 0) {
3838 PGRP_LOCK(sigio->sio_pgrp);
3839 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3841 if (p->p_state == PRS_NORMAL &&
3842 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3843 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3844 kern_psignal(p, sig);
3847 PGRP_UNLOCK(sigio->sio_pgrp);
3853 filt_sigattach(struct knote *kn)
3855 struct proc *p = curproc;
3857 kn->kn_ptr.p_proc = p;
3858 kn->kn_flags |= EV_CLEAR; /* automatically set */
3860 knlist_add(p->p_klist, kn, 0);
3866 filt_sigdetach(struct knote *kn)
3868 struct proc *p = kn->kn_ptr.p_proc;
3870 knlist_remove(p->p_klist, kn, 0);
3874 * signal knotes are shared with proc knotes, so we apply a mask to
3875 * the hint in order to differentiate them from process hints. This
3876 * could be avoided by using a signal-specific knote list, but probably
3877 * isn't worth the trouble.
3880 filt_signal(struct knote *kn, long hint)
3883 if (hint & NOTE_SIGNAL) {
3884 hint &= ~NOTE_SIGNAL;
3886 if (kn->kn_id == hint)
3889 return (kn->kn_data != 0);
3897 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3898 refcount_init(&ps->ps_refcnt, 1);
3899 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3904 sigacts_free(struct sigacts *ps)
3907 if (refcount_release(&ps->ps_refcnt) == 0)
3909 mtx_destroy(&ps->ps_mtx);
3910 free(ps, M_SUBPROC);
3914 sigacts_hold(struct sigacts *ps)
3917 refcount_acquire(&ps->ps_refcnt);
3922 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3925 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3926 mtx_lock(&src->ps_mtx);
3927 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3928 mtx_unlock(&src->ps_mtx);
3932 sigacts_shared(struct sigacts *ps)
3935 return (ps->ps_refcnt > 1);
3939 sig_drop_caught(struct proc *p)
3945 PROC_LOCK_ASSERT(p, MA_OWNED);
3946 mtx_assert(&ps->ps_mtx, MA_OWNED);
3947 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
3948 sig = sig_ffs(&ps->ps_sigcatch);
3950 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
3951 sigqueue_delete_proc(p, sig);
3956 sys_sigfastblock(struct thread *td, struct sigfastblock_args *uap)
3964 case SIGFASTBLOCK_SETPTR:
3965 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
3969 if (((uintptr_t)(uap->ptr) & (sizeof(uint32_t) - 1)) != 0) {
3973 td->td_pflags |= TDP_SIGFASTBLOCK;
3974 td->td_sigblock_ptr = uap->ptr;
3977 case SIGFASTBLOCK_UNBLOCK:
3978 if ((td->td_pflags & TDP_SIGFASTBLOCK) != 0) {
3983 res = casueword32(td->td_sigblock_ptr, SIGFASTBLOCK_PEND,
3990 if (oldval != SIGFASTBLOCK_PEND) {
3994 error = thread_check_susp(td, false);
3999 td->td_sigblock_val = 0;
4002 * Rely on normal ast mechanism to deliver pending
4003 * signals to current thread. But notify others about
4007 if (error == 0 && p->p_numthreads != 1) {
4009 reschedule_signals(p, td->td_sigmask, 0);
4014 case SIGFASTBLOCK_UNSETPTR:
4015 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0) {
4019 res = fueword32(td->td_sigblock_ptr, &oldval);
4024 if (oldval != 0 && oldval != SIGFASTBLOCK_PEND) {
4028 td->td_pflags &= ~TDP_SIGFASTBLOCK;
4029 td->td_sigblock_val = 0;
4040 fetch_sigfastblock(struct thread *td)
4043 if ((td->td_pflags & TDP_SIGFASTBLOCK) == 0)
4045 if (fueword32(td->td_sigblock_ptr, &td->td_sigblock_val) == -1) {
4046 fetch_sigfastblock_failed(td, false);
4049 td->td_sigblock_val &= ~SIGFASTBLOCK_FLAGS;
4053 fetch_sigfastblock_failed(struct thread *td, bool write)
4058 * Prevent further fetches and SIGSEGVs, allowing thread to
4059 * issue syscalls despite corruption.
4061 td->td_pflags &= ~TDP_SIGFASTBLOCK;
4063 ksiginfo_init_trap(&ksi);
4064 ksi.ksi_signo = SIGSEGV;
4065 ksi.ksi_code = write ? SEGV_ACCERR : SEGV_MAPERR;
4066 ksi.ksi_addr = td->td_sigblock_ptr;
4067 trapsignal(td, &ksi);