2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
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8 * the permission of UNIX System Laboratories, Inc.
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13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
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34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
41 #include "opt_kdtrace.h"
42 #include "opt_ktrace.h"
44 #include "opt_procdesc.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/signalvar.h>
49 #include <sys/vnode.h>
51 #include <sys/capability.h>
52 #include <sys/condvar.h>
53 #include <sys/event.h>
54 #include <sys/fcntl.h>
55 #include <sys/imgact.h>
56 #include <sys/kernel.h>
58 #include <sys/ktrace.h>
60 #include <sys/malloc.h>
61 #include <sys/mutex.h>
62 #include <sys/namei.h>
64 #include <sys/procdesc.h>
65 #include <sys/posix4.h>
66 #include <sys/pioctl.h>
67 #include <sys/racct.h>
68 #include <sys/resourcevar.h>
71 #include <sys/sleepqueue.h>
75 #include <sys/syscallsubr.h>
76 #include <sys/sysctl.h>
77 #include <sys/sysent.h>
78 #include <sys/syslog.h>
79 #include <sys/sysproto.h>
80 #include <sys/timers.h>
81 #include <sys/unistd.h>
84 #include <vm/vm_extern.h>
89 #include <machine/cpu.h>
91 #include <security/audit/audit.h>
93 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
95 SDT_PROVIDER_DECLARE(proc);
96 SDT_PROBE_DEFINE(proc, kernel, , signal_send, signal-send);
97 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 0, "struct thread *");
98 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 1, "struct proc *");
99 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 2, "int");
100 SDT_PROBE_DEFINE(proc, kernel, , signal_clear, signal-clear);
101 SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 0, "int");
102 SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 1, "ksiginfo_t *");
103 SDT_PROBE_DEFINE(proc, kernel, , signal_discard, signal-discard);
104 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 0, "struct thread *");
105 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 1, "struct proc *");
106 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 2, "int");
108 static int coredump(struct thread *);
109 static int killpg1(struct thread *td, int sig, int pgid, int all,
111 static int issignal(struct thread *td, int stop_allowed);
112 static int sigprop(int sig);
113 static void tdsigwakeup(struct thread *, int, sig_t, int);
114 static void sig_suspend_threads(struct thread *, struct proc *, int);
115 static int filt_sigattach(struct knote *kn);
116 static void filt_sigdetach(struct knote *kn);
117 static int filt_signal(struct knote *kn, long hint);
118 static struct thread *sigtd(struct proc *p, int sig, int prop);
119 static void sigqueue_start(void);
121 static uma_zone_t ksiginfo_zone = NULL;
122 struct filterops sig_filtops = {
124 .f_attach = filt_sigattach,
125 .f_detach = filt_sigdetach,
126 .f_event = filt_signal,
129 static int kern_logsigexit = 1;
130 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
132 "Log processes quitting on abnormal signals to syslog(3)");
134 static int kern_forcesigexit = 1;
135 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
136 &kern_forcesigexit, 0, "Force trap signal to be handled");
138 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
139 "POSIX real time signal");
141 static int max_pending_per_proc = 128;
142 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
143 &max_pending_per_proc, 0, "Max pending signals per proc");
145 static int preallocate_siginfo = 1024;
146 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
147 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
148 &preallocate_siginfo, 0, "Preallocated signal memory size");
150 static int signal_overflow = 0;
151 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
152 &signal_overflow, 0, "Number of signals overflew");
154 static int signal_alloc_fail = 0;
155 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
156 &signal_alloc_fail, 0, "signals failed to be allocated");
158 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
161 * Policy -- Can ucred cr1 send SIGIO to process cr2?
162 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
163 * in the right situations.
165 #define CANSIGIO(cr1, cr2) \
166 ((cr1)->cr_uid == 0 || \
167 (cr1)->cr_ruid == (cr2)->cr_ruid || \
168 (cr1)->cr_uid == (cr2)->cr_ruid || \
169 (cr1)->cr_ruid == (cr2)->cr_uid || \
170 (cr1)->cr_uid == (cr2)->cr_uid)
172 static int sugid_coredump;
173 TUNABLE_INT("kern.sugid_coredump", &sugid_coredump);
174 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
175 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
177 static int capmode_coredump;
178 TUNABLE_INT("kern.capmode_coredump", &capmode_coredump);
179 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RW,
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");
191 * Signal properties and actions.
192 * The array below categorizes the signals and their default actions
193 * according to the following properties:
195 #define SA_KILL 0x01 /* terminates process by default */
196 #define SA_CORE 0x02 /* ditto and coredumps */
197 #define SA_STOP 0x04 /* suspend process */
198 #define SA_TTYSTOP 0x08 /* ditto, from tty */
199 #define SA_IGNORE 0x10 /* ignore by default */
200 #define SA_CONT 0x20 /* continue if suspended */
201 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
203 static int sigproptbl[NSIG] = {
204 SA_KILL, /* SIGHUP */
205 SA_KILL, /* SIGINT */
206 SA_KILL|SA_CORE, /* SIGQUIT */
207 SA_KILL|SA_CORE, /* SIGILL */
208 SA_KILL|SA_CORE, /* SIGTRAP */
209 SA_KILL|SA_CORE, /* SIGABRT */
210 SA_KILL|SA_CORE, /* SIGEMT */
211 SA_KILL|SA_CORE, /* SIGFPE */
212 SA_KILL, /* SIGKILL */
213 SA_KILL|SA_CORE, /* SIGBUS */
214 SA_KILL|SA_CORE, /* SIGSEGV */
215 SA_KILL|SA_CORE, /* SIGSYS */
216 SA_KILL, /* SIGPIPE */
217 SA_KILL, /* SIGALRM */
218 SA_KILL, /* SIGTERM */
219 SA_IGNORE, /* SIGURG */
220 SA_STOP, /* SIGSTOP */
221 SA_STOP|SA_TTYSTOP, /* SIGTSTP */
222 SA_IGNORE|SA_CONT, /* SIGCONT */
223 SA_IGNORE, /* SIGCHLD */
224 SA_STOP|SA_TTYSTOP, /* SIGTTIN */
225 SA_STOP|SA_TTYSTOP, /* SIGTTOU */
226 SA_IGNORE, /* SIGIO */
227 SA_KILL, /* SIGXCPU */
228 SA_KILL, /* SIGXFSZ */
229 SA_KILL, /* SIGVTALRM */
230 SA_KILL, /* SIGPROF */
231 SA_IGNORE, /* SIGWINCH */
232 SA_IGNORE, /* SIGINFO */
233 SA_KILL, /* SIGUSR1 */
234 SA_KILL, /* SIGUSR2 */
237 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
242 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
243 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
244 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
245 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
246 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
247 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
251 ksiginfo_alloc(int wait)
258 if (ksiginfo_zone != NULL)
259 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
264 ksiginfo_free(ksiginfo_t *ksi)
266 uma_zfree(ksiginfo_zone, ksi);
270 ksiginfo_tryfree(ksiginfo_t *ksi)
272 if (!(ksi->ksi_flags & KSI_EXT)) {
273 uma_zfree(ksiginfo_zone, ksi);
280 sigqueue_init(sigqueue_t *list, struct proc *p)
282 SIGEMPTYSET(list->sq_signals);
283 SIGEMPTYSET(list->sq_kill);
284 TAILQ_INIT(&list->sq_list);
286 list->sq_flags = SQ_INIT;
290 * Get a signal's ksiginfo.
292 * 0 - signal not found
293 * others - signal number
296 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
298 struct proc *p = sq->sq_proc;
299 struct ksiginfo *ksi, *next;
302 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
304 if (!SIGISMEMBER(sq->sq_signals, signo))
307 if (SIGISMEMBER(sq->sq_kill, signo)) {
309 SIGDELSET(sq->sq_kill, signo);
312 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
313 if (ksi->ksi_signo == signo) {
315 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
316 ksi->ksi_sigq = NULL;
317 ksiginfo_copy(ksi, si);
318 if (ksiginfo_tryfree(ksi) && p != NULL)
327 SIGDELSET(sq->sq_signals, signo);
328 si->ksi_signo = signo;
333 sigqueue_take(ksiginfo_t *ksi)
339 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
343 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
344 ksi->ksi_sigq = NULL;
345 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
348 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
349 kp = TAILQ_NEXT(kp, ksi_link)) {
350 if (kp->ksi_signo == ksi->ksi_signo)
353 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
354 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
358 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
360 struct proc *p = sq->sq_proc;
361 struct ksiginfo *ksi;
364 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
366 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
367 SIGADDSET(sq->sq_kill, signo);
371 /* directly insert the ksi, don't copy it */
372 if (si->ksi_flags & KSI_INS) {
373 if (si->ksi_flags & KSI_HEAD)
374 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
376 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
381 if (__predict_false(ksiginfo_zone == NULL)) {
382 SIGADDSET(sq->sq_kill, signo);
386 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
389 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
395 ksiginfo_copy(si, ksi);
396 ksi->ksi_signo = signo;
397 if (si->ksi_flags & KSI_HEAD)
398 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
400 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
404 if ((si->ksi_flags & KSI_TRAP) != 0 ||
405 (si->ksi_flags & KSI_SIGQ) == 0) {
407 SIGADDSET(sq->sq_kill, signo);
416 SIGADDSET(sq->sq_signals, signo);
421 sigqueue_flush(sigqueue_t *sq)
423 struct proc *p = sq->sq_proc;
426 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
429 PROC_LOCK_ASSERT(p, MA_OWNED);
431 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
432 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
433 ksi->ksi_sigq = NULL;
434 if (ksiginfo_tryfree(ksi) && p != NULL)
438 SIGEMPTYSET(sq->sq_signals);
439 SIGEMPTYSET(sq->sq_kill);
443 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
446 struct proc *p1, *p2;
447 ksiginfo_t *ksi, *next;
449 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
450 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
453 /* Move siginfo to target list */
454 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
455 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
456 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
459 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
466 /* Move pending bits to target list */
468 SIGSETAND(tmp, *set);
469 SIGSETOR(dst->sq_kill, tmp);
470 SIGSETNAND(src->sq_kill, tmp);
472 tmp = src->sq_signals;
473 SIGSETAND(tmp, *set);
474 SIGSETOR(dst->sq_signals, tmp);
475 SIGSETNAND(src->sq_signals, tmp);
480 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
485 SIGADDSET(set, signo);
486 sigqueue_move_set(src, dst, &set);
491 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
493 struct proc *p = sq->sq_proc;
494 ksiginfo_t *ksi, *next;
496 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
498 /* Remove siginfo queue */
499 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
500 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
501 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
502 ksi->ksi_sigq = NULL;
503 if (ksiginfo_tryfree(ksi) && p != NULL)
507 SIGSETNAND(sq->sq_kill, *set);
508 SIGSETNAND(sq->sq_signals, *set);
512 sigqueue_delete(sigqueue_t *sq, int signo)
517 SIGADDSET(set, signo);
518 sigqueue_delete_set(sq, &set);
521 /* Remove a set of signals for a process */
523 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
528 PROC_LOCK_ASSERT(p, MA_OWNED);
530 sigqueue_init(&worklist, NULL);
531 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
533 FOREACH_THREAD_IN_PROC(p, td0)
534 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
536 sigqueue_flush(&worklist);
540 sigqueue_delete_proc(struct proc *p, int signo)
545 SIGADDSET(set, signo);
546 sigqueue_delete_set_proc(p, &set);
550 sigqueue_delete_stopmask_proc(struct proc *p)
555 SIGADDSET(set, SIGSTOP);
556 SIGADDSET(set, SIGTSTP);
557 SIGADDSET(set, SIGTTIN);
558 SIGADDSET(set, SIGTTOU);
559 sigqueue_delete_set_proc(p, &set);
563 * Determine signal that should be delivered to process p, the current
564 * process, 0 if none. If there is a pending stop signal with default
565 * action, the process stops in issignal().
568 cursig(struct thread *td, int stop_allowed)
570 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
571 KASSERT(stop_allowed == SIG_STOP_ALLOWED ||
572 stop_allowed == SIG_STOP_NOT_ALLOWED, ("cursig: stop_allowed"));
573 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
574 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
575 return (SIGPENDING(td) ? issignal(td, stop_allowed) : 0);
579 * Arrange for ast() to handle unmasked pending signals on return to user
580 * mode. This must be called whenever a signal is added to td_sigqueue or
581 * unmasked in td_sigmask.
584 signotify(struct thread *td)
590 PROC_LOCK_ASSERT(p, MA_OWNED);
592 if (SIGPENDING(td)) {
594 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
600 sigonstack(size_t sp)
602 struct thread *td = curthread;
604 return ((td->td_pflags & TDP_ALTSTACK) ?
605 #if defined(COMPAT_43)
606 ((td->td_sigstk.ss_size == 0) ?
607 (td->td_sigstk.ss_flags & SS_ONSTACK) :
608 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
610 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
619 if (sig > 0 && sig < NSIG)
620 return (sigproptbl[_SIG_IDX(sig)]);
625 sig_ffs(sigset_t *set)
629 for (i = 0; i < _SIG_WORDS; i++)
631 return (ffs(set->__bits[i]) + (i * 32));
642 kern_sigaction(td, sig, act, oact, flags)
645 struct sigaction *act, *oact;
649 struct proc *p = td->td_proc;
651 if (!_SIG_VALID(sig))
656 mtx_lock(&ps->ps_mtx);
658 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
660 if (SIGISMEMBER(ps->ps_sigonstack, sig))
661 oact->sa_flags |= SA_ONSTACK;
662 if (!SIGISMEMBER(ps->ps_sigintr, sig))
663 oact->sa_flags |= SA_RESTART;
664 if (SIGISMEMBER(ps->ps_sigreset, sig))
665 oact->sa_flags |= SA_RESETHAND;
666 if (SIGISMEMBER(ps->ps_signodefer, sig))
667 oact->sa_flags |= SA_NODEFER;
668 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
669 oact->sa_flags |= SA_SIGINFO;
671 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
673 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
674 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
675 oact->sa_flags |= SA_NOCLDSTOP;
676 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
677 oact->sa_flags |= SA_NOCLDWAIT;
680 if ((sig == SIGKILL || sig == SIGSTOP) &&
681 act->sa_handler != SIG_DFL) {
682 mtx_unlock(&ps->ps_mtx);
688 * Change setting atomically.
691 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
692 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
693 if (act->sa_flags & SA_SIGINFO) {
694 ps->ps_sigact[_SIG_IDX(sig)] =
695 (__sighandler_t *)act->sa_sigaction;
696 SIGADDSET(ps->ps_siginfo, sig);
698 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
699 SIGDELSET(ps->ps_siginfo, sig);
701 if (!(act->sa_flags & SA_RESTART))
702 SIGADDSET(ps->ps_sigintr, sig);
704 SIGDELSET(ps->ps_sigintr, sig);
705 if (act->sa_flags & SA_ONSTACK)
706 SIGADDSET(ps->ps_sigonstack, sig);
708 SIGDELSET(ps->ps_sigonstack, sig);
709 if (act->sa_flags & SA_RESETHAND)
710 SIGADDSET(ps->ps_sigreset, sig);
712 SIGDELSET(ps->ps_sigreset, sig);
713 if (act->sa_flags & SA_NODEFER)
714 SIGADDSET(ps->ps_signodefer, sig);
716 SIGDELSET(ps->ps_signodefer, sig);
717 if (sig == SIGCHLD) {
718 if (act->sa_flags & SA_NOCLDSTOP)
719 ps->ps_flag |= PS_NOCLDSTOP;
721 ps->ps_flag &= ~PS_NOCLDSTOP;
722 if (act->sa_flags & SA_NOCLDWAIT) {
724 * Paranoia: since SA_NOCLDWAIT is implemented
725 * by reparenting the dying child to PID 1 (and
726 * trust it to reap the zombie), PID 1 itself
727 * is forbidden to set SA_NOCLDWAIT.
730 ps->ps_flag &= ~PS_NOCLDWAIT;
732 ps->ps_flag |= PS_NOCLDWAIT;
734 ps->ps_flag &= ~PS_NOCLDWAIT;
735 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
736 ps->ps_flag |= PS_CLDSIGIGN;
738 ps->ps_flag &= ~PS_CLDSIGIGN;
741 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
742 * and for signals set to SIG_DFL where the default is to
743 * ignore. However, don't put SIGCONT in ps_sigignore, as we
744 * have to restart the process.
746 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
747 (sigprop(sig) & SA_IGNORE &&
748 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
749 /* never to be seen again */
750 sigqueue_delete_proc(p, sig);
752 /* easier in psignal */
753 SIGADDSET(ps->ps_sigignore, sig);
754 SIGDELSET(ps->ps_sigcatch, sig);
756 SIGDELSET(ps->ps_sigignore, sig);
757 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
758 SIGDELSET(ps->ps_sigcatch, sig);
760 SIGADDSET(ps->ps_sigcatch, sig);
762 #ifdef COMPAT_FREEBSD4
763 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
764 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
765 (flags & KSA_FREEBSD4) == 0)
766 SIGDELSET(ps->ps_freebsd4, sig);
768 SIGADDSET(ps->ps_freebsd4, sig);
771 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
772 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
773 (flags & KSA_OSIGSET) == 0)
774 SIGDELSET(ps->ps_osigset, sig);
776 SIGADDSET(ps->ps_osigset, sig);
779 mtx_unlock(&ps->ps_mtx);
784 #ifndef _SYS_SYSPROTO_H_
785 struct sigaction_args {
787 struct sigaction *act;
788 struct sigaction *oact;
792 sys_sigaction(td, uap)
794 register struct sigaction_args *uap;
796 struct sigaction act, oact;
797 register struct sigaction *actp, *oactp;
800 actp = (uap->act != NULL) ? &act : NULL;
801 oactp = (uap->oact != NULL) ? &oact : NULL;
803 error = copyin(uap->act, actp, sizeof(act));
807 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
809 error = copyout(oactp, uap->oact, sizeof(oact));
813 #ifdef COMPAT_FREEBSD4
814 #ifndef _SYS_SYSPROTO_H_
815 struct freebsd4_sigaction_args {
817 struct sigaction *act;
818 struct sigaction *oact;
822 freebsd4_sigaction(td, uap)
824 register struct freebsd4_sigaction_args *uap;
826 struct sigaction act, oact;
827 register struct sigaction *actp, *oactp;
831 actp = (uap->act != NULL) ? &act : NULL;
832 oactp = (uap->oact != NULL) ? &oact : NULL;
834 error = copyin(uap->act, actp, sizeof(act));
838 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
840 error = copyout(oactp, uap->oact, sizeof(oact));
843 #endif /* COMAPT_FREEBSD4 */
845 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
846 #ifndef _SYS_SYSPROTO_H_
847 struct osigaction_args {
849 struct osigaction *nsa;
850 struct osigaction *osa;
856 register struct osigaction_args *uap;
858 struct osigaction sa;
859 struct sigaction nsa, osa;
860 register struct sigaction *nsap, *osap;
863 if (uap->signum <= 0 || uap->signum >= ONSIG)
866 nsap = (uap->nsa != NULL) ? &nsa : NULL;
867 osap = (uap->osa != NULL) ? &osa : NULL;
870 error = copyin(uap->nsa, &sa, sizeof(sa));
873 nsap->sa_handler = sa.sa_handler;
874 nsap->sa_flags = sa.sa_flags;
875 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
877 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
878 if (osap && !error) {
879 sa.sa_handler = osap->sa_handler;
880 sa.sa_flags = osap->sa_flags;
881 SIG2OSIG(osap->sa_mask, sa.sa_mask);
882 error = copyout(&sa, uap->osa, sizeof(sa));
887 #if !defined(__i386__)
888 /* Avoid replicating the same stub everywhere */
892 struct osigreturn_args *uap;
895 return (nosys(td, (struct nosys_args *)uap));
898 #endif /* COMPAT_43 */
901 * Initialize signal state for process 0;
902 * set to ignore signals that are ignored by default.
913 mtx_lock(&ps->ps_mtx);
914 for (i = 1; i <= NSIG; i++)
915 if (sigprop(i) & SA_IGNORE && i != SIGCONT)
916 SIGADDSET(ps->ps_sigignore, i);
917 mtx_unlock(&ps->ps_mtx);
922 * Reset signals for an exec of the specified process.
925 execsigs(struct proc *p)
932 * Reset caught signals. Held signals remain held
933 * through td_sigmask (unless they were caught,
934 * and are now ignored by default).
936 PROC_LOCK_ASSERT(p, MA_OWNED);
937 td = FIRST_THREAD_IN_PROC(p);
939 mtx_lock(&ps->ps_mtx);
940 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
941 sig = sig_ffs(&ps->ps_sigcatch);
942 SIGDELSET(ps->ps_sigcatch, sig);
943 if (sigprop(sig) & SA_IGNORE) {
945 SIGADDSET(ps->ps_sigignore, sig);
946 sigqueue_delete_proc(p, sig);
948 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
951 * Reset stack state to the user stack.
952 * Clear set of signals caught on the signal stack.
954 td->td_sigstk.ss_flags = SS_DISABLE;
955 td->td_sigstk.ss_size = 0;
956 td->td_sigstk.ss_sp = 0;
957 td->td_pflags &= ~TDP_ALTSTACK;
959 * Reset no zombies if child dies flag as Solaris does.
961 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
962 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
963 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
964 mtx_unlock(&ps->ps_mtx);
970 * Manipulate signal mask.
973 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
976 sigset_t new_block, oset1;
981 if (!(flags & SIGPROCMASK_PROC_LOCKED))
984 *oset = td->td_sigmask;
991 oset1 = td->td_sigmask;
992 SIGSETOR(td->td_sigmask, *set);
993 new_block = td->td_sigmask;
994 SIGSETNAND(new_block, oset1);
997 SIGSETNAND(td->td_sigmask, *set);
1002 oset1 = td->td_sigmask;
1003 if (flags & SIGPROCMASK_OLD)
1004 SIGSETLO(td->td_sigmask, *set);
1006 td->td_sigmask = *set;
1007 new_block = td->td_sigmask;
1008 SIGSETNAND(new_block, oset1);
1017 * The new_block set contains signals that were not previously
1018 * blocked, but are blocked now.
1020 * In case we block any signal that was not previously blocked
1021 * for td, and process has the signal pending, try to schedule
1022 * signal delivery to some thread that does not block the
1023 * signal, possibly waking it up.
1025 if (p->p_numthreads != 1)
1026 reschedule_signals(p, new_block, flags);
1030 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1035 #ifndef _SYS_SYSPROTO_H_
1036 struct sigprocmask_args {
1038 const sigset_t *set;
1043 sys_sigprocmask(td, uap)
1044 register struct thread *td;
1045 struct sigprocmask_args *uap;
1048 sigset_t *setp, *osetp;
1051 setp = (uap->set != NULL) ? &set : NULL;
1052 osetp = (uap->oset != NULL) ? &oset : NULL;
1054 error = copyin(uap->set, setp, sizeof(set));
1058 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1059 if (osetp && !error) {
1060 error = copyout(osetp, uap->oset, sizeof(oset));
1065 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1066 #ifndef _SYS_SYSPROTO_H_
1067 struct osigprocmask_args {
1073 osigprocmask(td, uap)
1074 register struct thread *td;
1075 struct osigprocmask_args *uap;
1080 OSIG2SIG(uap->mask, set);
1081 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1082 SIG2OSIG(oset, td->td_retval[0]);
1085 #endif /* COMPAT_43 */
1088 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1094 error = copyin(uap->set, &set, sizeof(set));
1096 td->td_retval[0] = error;
1100 error = kern_sigtimedwait(td, set, &ksi, NULL);
1102 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1104 if (error == ERESTART)
1106 td->td_retval[0] = error;
1110 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1111 td->td_retval[0] = error;
1116 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1119 struct timespec *timeout;
1125 error = copyin(uap->timeout, &ts, sizeof(ts));
1133 error = copyin(uap->set, &set, sizeof(set));
1137 error = kern_sigtimedwait(td, set, &ksi, timeout);
1142 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1145 td->td_retval[0] = ksi.ksi_signo;
1150 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1156 error = copyin(uap->set, &set, sizeof(set));
1160 error = kern_sigtimedwait(td, set, &ksi, NULL);
1165 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1168 td->td_retval[0] = ksi.ksi_signo;
1173 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1174 struct timespec *timeout)
1177 sigset_t saved_mask, new_block;
1179 int error, sig, timo, timevalid = 0;
1180 struct timespec rts, ets, ts;
1188 if (timeout != NULL) {
1189 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1191 getnanouptime(&rts);
1193 timespecadd(&ets, timeout);
1197 /* Some signals can not be waited for. */
1198 SIG_CANTMASK(waitset);
1201 saved_mask = td->td_sigmask;
1202 SIGSETNAND(td->td_sigmask, waitset);
1204 mtx_lock(&ps->ps_mtx);
1205 sig = cursig(td, SIG_STOP_ALLOWED);
1206 mtx_unlock(&ps->ps_mtx);
1207 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1208 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1209 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1219 * POSIX says this must be checked after looking for pending
1222 if (timeout != NULL) {
1227 getnanouptime(&rts);
1228 if (timespeccmp(&rts, &ets, >=)) {
1233 timespecsub(&ts, &rts);
1234 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1240 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1242 if (timeout != NULL) {
1243 if (error == ERESTART) {
1244 /* Timeout can not be restarted. */
1246 } else if (error == EAGAIN) {
1247 /* We will calculate timeout by ourself. */
1253 new_block = saved_mask;
1254 SIGSETNAND(new_block, td->td_sigmask);
1255 td->td_sigmask = saved_mask;
1257 * Fewer signals can be delivered to us, reschedule signal
1260 if (p->p_numthreads != 1)
1261 reschedule_signals(p, new_block, 0);
1264 SDT_PROBE(proc, kernel, , signal_clear, sig, ksi, 0, 0, 0);
1266 if (ksi->ksi_code == SI_TIMER)
1267 itimer_accept(p, ksi->ksi_timerid, ksi);
1270 if (KTRPOINT(td, KTR_PSIG)) {
1273 mtx_lock(&ps->ps_mtx);
1274 action = ps->ps_sigact[_SIG_IDX(sig)];
1275 mtx_unlock(&ps->ps_mtx);
1276 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1286 #ifndef _SYS_SYSPROTO_H_
1287 struct sigpending_args {
1292 sys_sigpending(td, uap)
1294 struct sigpending_args *uap;
1296 struct proc *p = td->td_proc;
1300 pending = p->p_sigqueue.sq_signals;
1301 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1303 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1306 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1307 #ifndef _SYS_SYSPROTO_H_
1308 struct osigpending_args {
1313 osigpending(td, uap)
1315 struct osigpending_args *uap;
1317 struct proc *p = td->td_proc;
1321 pending = p->p_sigqueue.sq_signals;
1322 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1324 SIG2OSIG(pending, td->td_retval[0]);
1327 #endif /* COMPAT_43 */
1329 #if defined(COMPAT_43)
1331 * Generalized interface signal handler, 4.3-compatible.
1333 #ifndef _SYS_SYSPROTO_H_
1334 struct osigvec_args {
1344 register struct osigvec_args *uap;
1347 struct sigaction nsa, osa;
1348 register struct sigaction *nsap, *osap;
1351 if (uap->signum <= 0 || uap->signum >= ONSIG)
1353 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1354 osap = (uap->osv != NULL) ? &osa : NULL;
1356 error = copyin(uap->nsv, &vec, sizeof(vec));
1359 nsap->sa_handler = vec.sv_handler;
1360 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1361 nsap->sa_flags = vec.sv_flags;
1362 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1364 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1365 if (osap && !error) {
1366 vec.sv_handler = osap->sa_handler;
1367 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1368 vec.sv_flags = osap->sa_flags;
1369 vec.sv_flags &= ~SA_NOCLDWAIT;
1370 vec.sv_flags ^= SA_RESTART;
1371 error = copyout(&vec, uap->osv, sizeof(vec));
1376 #ifndef _SYS_SYSPROTO_H_
1377 struct osigblock_args {
1383 register struct thread *td;
1384 struct osigblock_args *uap;
1388 OSIG2SIG(uap->mask, set);
1389 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1390 SIG2OSIG(oset, td->td_retval[0]);
1394 #ifndef _SYS_SYSPROTO_H_
1395 struct osigsetmask_args {
1400 osigsetmask(td, uap)
1402 struct osigsetmask_args *uap;
1406 OSIG2SIG(uap->mask, set);
1407 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1408 SIG2OSIG(oset, td->td_retval[0]);
1411 #endif /* COMPAT_43 */
1414 * Suspend calling thread until signal, providing mask to be set in the
1417 #ifndef _SYS_SYSPROTO_H_
1418 struct sigsuspend_args {
1419 const sigset_t *sigmask;
1424 sys_sigsuspend(td, uap)
1426 struct sigsuspend_args *uap;
1431 error = copyin(uap->sigmask, &mask, sizeof(mask));
1434 return (kern_sigsuspend(td, mask));
1438 kern_sigsuspend(struct thread *td, sigset_t mask)
1440 struct proc *p = td->td_proc;
1444 * When returning from sigsuspend, we want
1445 * the old mask to be restored after the
1446 * signal handler has finished. Thus, we
1447 * save it here and mark the sigacts structure
1451 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1452 SIGPROCMASK_PROC_LOCKED);
1453 td->td_pflags |= TDP_OLDMASK;
1456 * Process signals now. Otherwise, we can get spurious wakeup
1457 * due to signal entered process queue, but delivered to other
1458 * thread. But sigsuspend should return only on signal
1461 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1462 for (has_sig = 0; !has_sig;) {
1463 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1466 thread_suspend_check(0);
1467 mtx_lock(&p->p_sigacts->ps_mtx);
1468 while ((sig = cursig(td, SIG_STOP_ALLOWED)) != 0)
1469 has_sig += postsig(sig);
1470 mtx_unlock(&p->p_sigacts->ps_mtx);
1473 td->td_errno = EINTR;
1474 td->td_pflags |= TDP_NERRNO;
1475 return (EJUSTRETURN);
1478 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1480 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1481 * convention: libc stub passes mask, not pointer, to save a copyin.
1483 #ifndef _SYS_SYSPROTO_H_
1484 struct osigsuspend_args {
1490 osigsuspend(td, uap)
1492 struct osigsuspend_args *uap;
1496 OSIG2SIG(uap->mask, mask);
1497 return (kern_sigsuspend(td, mask));
1499 #endif /* COMPAT_43 */
1501 #if defined(COMPAT_43)
1502 #ifndef _SYS_SYSPROTO_H_
1503 struct osigstack_args {
1504 struct sigstack *nss;
1505 struct sigstack *oss;
1512 register struct osigstack_args *uap;
1514 struct sigstack nss, oss;
1517 if (uap->nss != NULL) {
1518 error = copyin(uap->nss, &nss, sizeof(nss));
1522 oss.ss_sp = td->td_sigstk.ss_sp;
1523 oss.ss_onstack = sigonstack(cpu_getstack(td));
1524 if (uap->nss != NULL) {
1525 td->td_sigstk.ss_sp = nss.ss_sp;
1526 td->td_sigstk.ss_size = 0;
1527 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1528 td->td_pflags |= TDP_ALTSTACK;
1530 if (uap->oss != NULL)
1531 error = copyout(&oss, uap->oss, sizeof(oss));
1535 #endif /* COMPAT_43 */
1537 #ifndef _SYS_SYSPROTO_H_
1538 struct sigaltstack_args {
1545 sys_sigaltstack(td, uap)
1547 register struct sigaltstack_args *uap;
1552 if (uap->ss != NULL) {
1553 error = copyin(uap->ss, &ss, sizeof(ss));
1557 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1558 (uap->oss != NULL) ? &oss : NULL);
1561 if (uap->oss != NULL)
1562 error = copyout(&oss, uap->oss, sizeof(stack_t));
1567 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1569 struct proc *p = td->td_proc;
1572 oonstack = sigonstack(cpu_getstack(td));
1575 *oss = td->td_sigstk;
1576 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1577 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1583 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1585 if (!(ss->ss_flags & SS_DISABLE)) {
1586 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1589 td->td_sigstk = *ss;
1590 td->td_pflags |= TDP_ALTSTACK;
1592 td->td_pflags &= ~TDP_ALTSTACK;
1599 * Common code for kill process group/broadcast kill.
1600 * cp is calling process.
1603 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1615 sx_slock(&allproc_lock);
1616 FOREACH_PROC_IN_SYSTEM(p) {
1618 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1619 p == td->td_proc || p->p_state == PRS_NEW) {
1623 err = p_cansignal(td, p, sig);
1626 pksignal(p, sig, ksi);
1629 else if (ret == ESRCH)
1633 sx_sunlock(&allproc_lock);
1635 sx_slock(&proctree_lock);
1638 * zero pgid means send to my process group.
1640 pgrp = td->td_proc->p_pgrp;
1643 pgrp = pgfind(pgid);
1645 sx_sunlock(&proctree_lock);
1649 sx_sunlock(&proctree_lock);
1650 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1652 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1653 p->p_state == PRS_NEW) {
1657 err = p_cansignal(td, p, sig);
1660 pksignal(p, sig, ksi);
1663 else if (ret == ESRCH)
1672 #ifndef _SYS_SYSPROTO_H_
1680 sys_kill(struct thread *td, struct kill_args *uap)
1687 * A process in capability mode can send signals only to himself.
1688 * The main rationale behind this is that abort(3) is implemented as
1689 * kill(getpid(), SIGABRT).
1691 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1694 AUDIT_ARG_SIGNUM(uap->signum);
1695 AUDIT_ARG_PID(uap->pid);
1696 if ((u_int)uap->signum > _SIG_MAXSIG)
1699 ksiginfo_init(&ksi);
1700 ksi.ksi_signo = uap->signum;
1701 ksi.ksi_code = SI_USER;
1702 ksi.ksi_pid = td->td_proc->p_pid;
1703 ksi.ksi_uid = td->td_ucred->cr_ruid;
1706 /* kill single process */
1707 if ((p = pfind(uap->pid)) == NULL) {
1708 if ((p = zpfind(uap->pid)) == NULL)
1711 AUDIT_ARG_PROCESS(p);
1712 error = p_cansignal(td, p, uap->signum);
1713 if (error == 0 && uap->signum)
1714 pksignal(p, uap->signum, &ksi);
1719 case -1: /* broadcast signal */
1720 return (killpg1(td, uap->signum, 0, 1, &ksi));
1721 case 0: /* signal own process group */
1722 return (killpg1(td, uap->signum, 0, 0, &ksi));
1723 default: /* negative explicit process group */
1724 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1732 struct pdkill_args *uap;
1738 AUDIT_ARG_SIGNUM(uap->signum);
1739 AUDIT_ARG_FD(uap->fd);
1740 if ((u_int)uap->signum > _SIG_MAXSIG)
1743 error = procdesc_find(td, uap->fd, CAP_PDKILL, &p);
1746 AUDIT_ARG_PROCESS(p);
1747 error = p_cansignal(td, p, uap->signum);
1748 if (error == 0 && uap->signum)
1749 kern_psignal(p, uap->signum);
1757 #if defined(COMPAT_43)
1758 #ifndef _SYS_SYSPROTO_H_
1759 struct okillpg_args {
1766 okillpg(struct thread *td, struct okillpg_args *uap)
1770 AUDIT_ARG_SIGNUM(uap->signum);
1771 AUDIT_ARG_PID(uap->pgid);
1772 if ((u_int)uap->signum > _SIG_MAXSIG)
1775 ksiginfo_init(&ksi);
1776 ksi.ksi_signo = uap->signum;
1777 ksi.ksi_code = SI_USER;
1778 ksi.ksi_pid = td->td_proc->p_pid;
1779 ksi.ksi_uid = td->td_ucred->cr_ruid;
1780 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1782 #endif /* COMPAT_43 */
1784 #ifndef _SYS_SYSPROTO_H_
1785 struct sigqueue_args {
1788 /* union sigval */ void *value;
1792 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1798 if ((u_int)uap->signum > _SIG_MAXSIG)
1802 * Specification says sigqueue can only send signal to
1808 if ((p = pfind(uap->pid)) == NULL) {
1809 if ((p = zpfind(uap->pid)) == NULL)
1812 error = p_cansignal(td, p, uap->signum);
1813 if (error == 0 && uap->signum != 0) {
1814 ksiginfo_init(&ksi);
1815 ksi.ksi_flags = KSI_SIGQ;
1816 ksi.ksi_signo = uap->signum;
1817 ksi.ksi_code = SI_QUEUE;
1818 ksi.ksi_pid = td->td_proc->p_pid;
1819 ksi.ksi_uid = td->td_ucred->cr_ruid;
1820 ksi.ksi_value.sival_ptr = uap->value;
1821 error = pksignal(p, ksi.ksi_signo, &ksi);
1828 * Send a signal to a process group.
1831 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1836 sx_slock(&proctree_lock);
1837 pgrp = pgfind(pgid);
1838 sx_sunlock(&proctree_lock);
1840 pgsignal(pgrp, sig, 0, ksi);
1847 * Send a signal to a process group. If checktty is 1,
1848 * limit to members which have a controlling terminal.
1851 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1856 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1857 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1859 if (p->p_state == PRS_NORMAL &&
1860 (checkctty == 0 || p->p_flag & P_CONTROLT))
1861 pksignal(p, sig, ksi);
1868 * Send a signal caused by a trap to the current thread. If it will be
1869 * caught immediately, deliver it with correct code. Otherwise, post it
1873 trapsignal(struct thread *td, ksiginfo_t *ksi)
1882 sig = ksi->ksi_signo;
1883 code = ksi->ksi_code;
1884 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1888 mtx_lock(&ps->ps_mtx);
1889 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1890 !SIGISMEMBER(td->td_sigmask, sig)) {
1891 td->td_ru.ru_nsignals++;
1893 if (KTRPOINT(curthread, KTR_PSIG))
1894 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1895 &td->td_sigmask, code);
1897 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1898 ksi, &td->td_sigmask);
1899 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1900 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1901 SIGADDSET(mask, sig);
1902 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1903 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1904 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1906 * See kern_sigaction() for origin of this code.
1908 SIGDELSET(ps->ps_sigcatch, sig);
1909 if (sig != SIGCONT &&
1910 sigprop(sig) & SA_IGNORE)
1911 SIGADDSET(ps->ps_sigignore, sig);
1912 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1914 mtx_unlock(&ps->ps_mtx);
1917 * Avoid a possible infinite loop if the thread
1918 * masking the signal or process is ignoring the
1921 if (kern_forcesigexit &&
1922 (SIGISMEMBER(td->td_sigmask, sig) ||
1923 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1924 SIGDELSET(td->td_sigmask, sig);
1925 SIGDELSET(ps->ps_sigcatch, sig);
1926 SIGDELSET(ps->ps_sigignore, sig);
1927 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1929 mtx_unlock(&ps->ps_mtx);
1930 p->p_code = code; /* XXX for core dump/debugger */
1931 p->p_sig = sig; /* XXX to verify code */
1932 tdsendsignal(p, td, sig, ksi);
1937 static struct thread *
1938 sigtd(struct proc *p, int sig, int prop)
1940 struct thread *td, *signal_td;
1942 PROC_LOCK_ASSERT(p, MA_OWNED);
1945 * Check if current thread can handle the signal without
1946 * switching context to another thread.
1948 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1951 FOREACH_THREAD_IN_PROC(p, td) {
1952 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1957 if (signal_td == NULL)
1958 signal_td = FIRST_THREAD_IN_PROC(p);
1963 * Send the signal to the process. If the signal has an action, the action
1964 * is usually performed by the target process rather than the caller; we add
1965 * the signal to the set of pending signals for the process.
1968 * o When a stop signal is sent to a sleeping process that takes the
1969 * default action, the process is stopped without awakening it.
1970 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1971 * regardless of the signal action (eg, blocked or ignored).
1973 * Other ignored signals are discarded immediately.
1975 * NB: This function may be entered from the debugger via the "kill" DDB
1976 * command. There is little that can be done to mitigate the possibly messy
1977 * side effects of this unwise possibility.
1980 kern_psignal(struct proc *p, int sig)
1984 ksiginfo_init(&ksi);
1985 ksi.ksi_signo = sig;
1986 ksi.ksi_code = SI_KERNEL;
1987 (void) tdsendsignal(p, NULL, sig, &ksi);
1991 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
1994 return (tdsendsignal(p, NULL, sig, ksi));
1997 /* Utility function for finding a thread to send signal event to. */
1999 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2003 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2004 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2016 tdsignal(struct thread *td, int sig)
2020 ksiginfo_init(&ksi);
2021 ksi.ksi_signo = sig;
2022 ksi.ksi_code = SI_KERNEL;
2023 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2027 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2030 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2034 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2037 sigqueue_t *sigqueue;
2044 MPASS(td == NULL || p == td->td_proc);
2045 PROC_LOCK_ASSERT(p, MA_OWNED);
2047 if (!_SIG_VALID(sig))
2048 panic("%s(): invalid signal %d", __func__, sig);
2050 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2053 * IEEE Std 1003.1-2001: return success when killing a zombie.
2055 if (p->p_state == PRS_ZOMBIE) {
2056 if (ksi && (ksi->ksi_flags & KSI_INS))
2057 ksiginfo_tryfree(ksi);
2062 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2063 prop = sigprop(sig);
2066 td = sigtd(p, sig, prop);
2067 sigqueue = &p->p_sigqueue;
2069 KASSERT(td->td_proc == p, ("invalid thread"));
2070 sigqueue = &td->td_sigqueue;
2073 SDT_PROBE(proc, kernel, , signal_send, td, p, sig, 0, 0 );
2076 * If the signal is being ignored,
2077 * then we forget about it immediately.
2078 * (Note: we don't set SIGCONT in ps_sigignore,
2079 * and if it is set to SIG_IGN,
2080 * action will be SIG_DFL here.)
2082 mtx_lock(&ps->ps_mtx);
2083 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2084 SDT_PROBE(proc, kernel, , signal_discard, td, p, sig, 0, 0 );
2086 mtx_unlock(&ps->ps_mtx);
2087 if (ksi && (ksi->ksi_flags & KSI_INS))
2088 ksiginfo_tryfree(ksi);
2091 if (SIGISMEMBER(td->td_sigmask, sig))
2093 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2097 if (SIGISMEMBER(ps->ps_sigintr, sig))
2101 mtx_unlock(&ps->ps_mtx);
2104 sigqueue_delete_stopmask_proc(p);
2105 else if (prop & SA_STOP) {
2107 * If sending a tty stop signal to a member of an orphaned
2108 * process group, discard the signal here if the action
2109 * is default; don't stop the process below if sleeping,
2110 * and don't clear any pending SIGCONT.
2112 if ((prop & SA_TTYSTOP) &&
2113 (p->p_pgrp->pg_jobc == 0) &&
2114 (action == SIG_DFL)) {
2115 if (ksi && (ksi->ksi_flags & KSI_INS))
2116 ksiginfo_tryfree(ksi);
2119 sigqueue_delete_proc(p, SIGCONT);
2120 if (p->p_flag & P_CONTINUED) {
2121 p->p_flag &= ~P_CONTINUED;
2122 PROC_LOCK(p->p_pptr);
2123 sigqueue_take(p->p_ksi);
2124 PROC_UNLOCK(p->p_pptr);
2128 ret = sigqueue_add(sigqueue, sig, ksi);
2133 * Defer further processing for signals which are held,
2134 * except that stopped processes must be continued by SIGCONT.
2136 if (action == SIG_HOLD &&
2137 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2140 * SIGKILL: Remove procfs STOPEVENTs.
2142 if (sig == SIGKILL) {
2143 /* from procfs_ioctl.c: PIOCBIC */
2145 /* from procfs_ioctl.c: PIOCCONT */
2150 * Some signals have a process-wide effect and a per-thread
2151 * component. Most processing occurs when the process next
2152 * tries to cross the user boundary, however there are some
2153 * times when processing needs to be done immediatly, such as
2154 * waking up threads so that they can cross the user boundary.
2155 * We try do the per-process part here.
2157 if (P_SHOULDSTOP(p)) {
2158 KASSERT(!(p->p_flag & P_WEXIT),
2159 ("signal to stopped but exiting process"));
2160 if (sig == SIGKILL) {
2162 * If traced process is already stopped,
2163 * then no further action is necessary.
2165 if (p->p_flag & P_TRACED)
2168 * SIGKILL sets process running.
2169 * It will die elsewhere.
2170 * All threads must be restarted.
2172 p->p_flag &= ~P_STOPPED_SIG;
2176 if (prop & SA_CONT) {
2178 * If traced process is already stopped,
2179 * then no further action is necessary.
2181 if (p->p_flag & P_TRACED)
2184 * If SIGCONT is default (or ignored), we continue the
2185 * process but don't leave the signal in sigqueue as
2186 * it has no further action. If SIGCONT is held, we
2187 * continue the process and leave the signal in
2188 * sigqueue. If the process catches SIGCONT, let it
2189 * handle the signal itself. If it isn't waiting on
2190 * an event, it goes back to run state.
2191 * Otherwise, process goes back to sleep state.
2193 p->p_flag &= ~P_STOPPED_SIG;
2195 if (p->p_numthreads == p->p_suspcount) {
2197 p->p_flag |= P_CONTINUED;
2198 p->p_xstat = SIGCONT;
2199 PROC_LOCK(p->p_pptr);
2200 childproc_continued(p);
2201 PROC_UNLOCK(p->p_pptr);
2204 if (action == SIG_DFL) {
2205 thread_unsuspend(p);
2207 sigqueue_delete(sigqueue, sig);
2210 if (action == SIG_CATCH) {
2212 * The process wants to catch it so it needs
2213 * to run at least one thread, but which one?
2219 * The signal is not ignored or caught.
2221 thread_unsuspend(p);
2226 if (prop & SA_STOP) {
2228 * If traced process is already stopped,
2229 * then no further action is necessary.
2231 if (p->p_flag & P_TRACED)
2234 * Already stopped, don't need to stop again
2235 * (If we did the shell could get confused).
2236 * Just make sure the signal STOP bit set.
2238 p->p_flag |= P_STOPPED_SIG;
2239 sigqueue_delete(sigqueue, sig);
2244 * All other kinds of signals:
2245 * If a thread is sleeping interruptibly, simulate a
2246 * wakeup so that when it is continued it will be made
2247 * runnable and can look at the signal. However, don't make
2248 * the PROCESS runnable, leave it stopped.
2249 * It may run a bit until it hits a thread_suspend_check().
2254 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2255 wakeup_swapper = sleepq_abort(td, intrval);
2262 * Mutexes are short lived. Threads waiting on them will
2263 * hit thread_suspend_check() soon.
2265 } else if (p->p_state == PRS_NORMAL) {
2266 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2267 tdsigwakeup(td, sig, action, intrval);
2271 MPASS(action == SIG_DFL);
2273 if (prop & SA_STOP) {
2274 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2276 p->p_flag |= P_STOPPED_SIG;
2279 sig_suspend_threads(td, p, 1);
2280 if (p->p_numthreads == p->p_suspcount) {
2282 * only thread sending signal to another
2283 * process can reach here, if thread is sending
2284 * signal to its process, because thread does
2285 * not suspend itself here, p_numthreads
2286 * should never be equal to p_suspcount.
2290 sigqueue_delete_proc(p, p->p_xstat);
2296 /* Not in "NORMAL" state. discard the signal. */
2297 sigqueue_delete(sigqueue, sig);
2302 * The process is not stopped so we need to apply the signal to all the
2306 tdsigwakeup(td, sig, action, intrval);
2308 thread_unsuspend(p);
2311 /* If we jump here, proc slock should not be owned. */
2312 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2317 * The force of a signal has been directed against a single
2318 * thread. We need to see what we can do about knocking it
2319 * out of any sleep it may be in etc.
2322 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2324 struct proc *p = td->td_proc;
2329 PROC_LOCK_ASSERT(p, MA_OWNED);
2330 prop = sigprop(sig);
2335 * Bring the priority of a thread up if we want it to get
2336 * killed in this lifetime.
2338 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2339 sched_prio(td, PUSER);
2340 if (TD_ON_SLEEPQ(td)) {
2342 * If thread is sleeping uninterruptibly
2343 * we can't interrupt the sleep... the signal will
2344 * be noticed when the process returns through
2345 * trap() or syscall().
2347 if ((td->td_flags & TDF_SINTR) == 0)
2350 * If SIGCONT is default (or ignored) and process is
2351 * asleep, we are finished; the process should not
2354 if ((prop & SA_CONT) && action == SIG_DFL) {
2357 sigqueue_delete(&p->p_sigqueue, sig);
2359 * It may be on either list in this state.
2360 * Remove from both for now.
2362 sigqueue_delete(&td->td_sigqueue, sig);
2367 * Don't awaken a sleeping thread for SIGSTOP if the
2368 * STOP signal is deferred.
2370 if ((prop & SA_STOP) && (td->td_flags & TDF_SBDRY))
2374 * Give low priority threads a better chance to run.
2376 if (td->td_priority > PUSER)
2377 sched_prio(td, PUSER);
2379 wakeup_swapper = sleepq_abort(td, intrval);
2382 * Other states do nothing with the signal immediately,
2383 * other than kicking ourselves if we are running.
2384 * It will either never be noticed, or noticed very soon.
2387 if (TD_IS_RUNNING(td) && td != curthread)
2399 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2404 PROC_LOCK_ASSERT(p, MA_OWNED);
2405 PROC_SLOCK_ASSERT(p, MA_OWNED);
2408 FOREACH_THREAD_IN_PROC(p, td2) {
2410 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2411 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2412 (td2->td_flags & TDF_SINTR)) {
2413 if (td2->td_flags & TDF_SBDRY) {
2415 * Once a thread is asleep with
2416 * TDF_SBDRY set, it should never
2417 * become suspended due to this check.
2419 KASSERT(!TD_IS_SUSPENDED(td2),
2420 ("thread with deferred stops suspended"));
2421 } else if (!TD_IS_SUSPENDED(td2)) {
2422 thread_suspend_one(td2);
2424 } else if (!TD_IS_SUSPENDED(td2)) {
2425 if (sending || td != td2)
2426 td2->td_flags |= TDF_ASTPENDING;
2428 if (TD_IS_RUNNING(td2) && td2 != td)
2429 forward_signal(td2);
2439 ptracestop(struct thread *td, int sig)
2441 struct proc *p = td->td_proc;
2443 PROC_LOCK_ASSERT(p, MA_OWNED);
2444 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2445 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2446 &p->p_mtx.lock_object, "Stopping for traced signal");
2448 td->td_dbgflags |= TDB_XSIG;
2451 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2452 if (p->p_flag & P_SINGLE_EXIT) {
2453 td->td_dbgflags &= ~TDB_XSIG;
2458 * Just make wait() to work, the last stopped thread
2463 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2464 sig_suspend_threads(td, p, 0);
2465 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2466 td->td_dbgflags &= ~TDB_STOPATFORK;
2467 cv_broadcast(&p->p_dbgwait);
2470 thread_suspend_switch(td);
2471 if (p->p_xthread == td)
2472 p->p_xthread = NULL;
2473 if (!(p->p_flag & P_TRACED))
2475 if (td->td_dbgflags & TDB_SUSPEND) {
2476 if (p->p_flag & P_SINGLE_EXIT)
2482 return (td->td_xsig);
2486 reschedule_signals(struct proc *p, sigset_t block, int flags)
2492 PROC_LOCK_ASSERT(p, MA_OWNED);
2493 if (SIGISEMPTY(p->p_siglist))
2496 SIGSETAND(block, p->p_siglist);
2497 while ((sig = sig_ffs(&block)) != 0) {
2498 SIGDELSET(block, sig);
2499 td = sigtd(p, sig, 0);
2501 if (!(flags & SIGPROCMASK_PS_LOCKED))
2502 mtx_lock(&ps->ps_mtx);
2503 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2504 tdsigwakeup(td, sig, SIG_CATCH,
2505 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2507 if (!(flags & SIGPROCMASK_PS_LOCKED))
2508 mtx_unlock(&ps->ps_mtx);
2513 tdsigcleanup(struct thread *td)
2519 PROC_LOCK_ASSERT(p, MA_OWNED);
2521 sigqueue_flush(&td->td_sigqueue);
2522 if (p->p_numthreads == 1)
2526 * Since we cannot handle signals, notify signal post code
2527 * about this by filling the sigmask.
2529 * Also, if needed, wake up thread(s) that do not block the
2530 * same signals as the exiting thread, since the thread might
2531 * have been selected for delivery and woken up.
2533 SIGFILLSET(unblocked);
2534 SIGSETNAND(unblocked, td->td_sigmask);
2535 SIGFILLSET(td->td_sigmask);
2536 reschedule_signals(p, unblocked, 0);
2540 /* Defer the delivery of SIGSTOP for the current thread. */
2542 sigdeferstop(struct thread *td)
2545 KASSERT(!(td->td_flags & TDF_SBDRY),
2546 ("attempt to set TDF_SBDRY recursively"));
2548 td->td_flags |= TDF_SBDRY;
2553 * Permit the delivery of SIGSTOP for the current thread. This does
2554 * not immediately suspend if a stop was posted. Instead, the thread
2555 * will suspend either via ast() or a subsequent interruptible sleep.
2558 sigallowstop(struct thread *td)
2561 KASSERT(td->td_flags & TDF_SBDRY,
2562 ("attempt to clear already-cleared TDF_SBDRY"));
2564 td->td_flags &= ~TDF_SBDRY;
2569 * If the current process has received a signal (should be caught or cause
2570 * termination, should interrupt current syscall), return the signal number.
2571 * Stop signals with default action are processed immediately, then cleared;
2572 * they aren't returned. This is checked after each entry to the system for
2573 * a syscall or trap (though this can usually be done without calling issignal
2574 * by checking the pending signal masks in cursig.) The normal call
2577 * while (sig = cursig(curthread))
2581 issignal(struct thread *td, int stop_allowed)
2585 struct sigqueue *queue;
2586 sigset_t sigpending;
2587 int sig, prop, newsig;
2591 mtx_assert(&ps->ps_mtx, MA_OWNED);
2592 PROC_LOCK_ASSERT(p, MA_OWNED);
2594 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2596 sigpending = td->td_sigqueue.sq_signals;
2597 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2598 SIGSETNAND(sigpending, td->td_sigmask);
2600 if (p->p_flag & P_PPWAIT || td->td_flags & TDF_SBDRY)
2601 SIG_STOPSIGMASK(sigpending);
2602 if (SIGISEMPTY(sigpending)) /* no signal to send */
2604 sig = sig_ffs(&sigpending);
2606 if (p->p_stops & S_SIG) {
2607 mtx_unlock(&ps->ps_mtx);
2608 stopevent(p, S_SIG, sig);
2609 mtx_lock(&ps->ps_mtx);
2613 * We should see pending but ignored signals
2614 * only if P_TRACED was on when they were posted.
2616 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2617 sigqueue_delete(&td->td_sigqueue, sig);
2618 sigqueue_delete(&p->p_sigqueue, sig);
2621 if (p->p_flag & P_TRACED && (p->p_flag & P_PPTRACE) == 0) {
2623 * If traced, always stop.
2624 * Remove old signal from queue before the stop.
2625 * XXX shrug off debugger, it causes siginfo to
2628 queue = &td->td_sigqueue;
2629 td->td_dbgksi.ksi_signo = 0;
2630 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2631 queue = &p->p_sigqueue;
2632 sigqueue_get(queue, sig, &td->td_dbgksi);
2635 mtx_unlock(&ps->ps_mtx);
2636 newsig = ptracestop(td, sig);
2637 mtx_lock(&ps->ps_mtx);
2639 if (sig != newsig) {
2642 * If parent wants us to take the signal,
2643 * then it will leave it in p->p_xstat;
2644 * otherwise we just look for signals again.
2651 * Put the new signal into td_sigqueue. If the
2652 * signal is being masked, look for other
2655 sigqueue_add(queue, sig, NULL);
2656 if (SIGISMEMBER(td->td_sigmask, sig))
2660 if (td->td_dbgksi.ksi_signo != 0) {
2661 td->td_dbgksi.ksi_flags |= KSI_HEAD;
2662 if (sigqueue_add(&td->td_sigqueue, sig,
2663 &td->td_dbgksi) != 0)
2664 td->td_dbgksi.ksi_signo = 0;
2666 if (td->td_dbgksi.ksi_signo == 0)
2667 sigqueue_add(&td->td_sigqueue, sig,
2672 * If the traced bit got turned off, go back up
2673 * to the top to rescan signals. This ensures
2674 * that p_sig* and p_sigact are consistent.
2676 if ((p->p_flag & P_TRACED) == 0)
2680 prop = sigprop(sig);
2683 * Decide whether the signal should be returned.
2684 * Return the signal's number, or fall through
2685 * to clear it from the pending mask.
2687 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2689 case (intptr_t)SIG_DFL:
2691 * Don't take default actions on system processes.
2693 if (p->p_pid <= 1) {
2696 * Are you sure you want to ignore SIGSEGV
2699 printf("Process (pid %lu) got signal %d\n",
2700 (u_long)p->p_pid, sig);
2702 break; /* == ignore */
2705 * If there is a pending stop signal to process
2706 * with default action, stop here,
2707 * then clear the signal. However,
2708 * if process is member of an orphaned
2709 * process group, ignore tty stop signals.
2711 if (prop & SA_STOP) {
2712 if (p->p_flag & (P_TRACED|P_WEXIT) ||
2713 (p->p_pgrp->pg_jobc == 0 &&
2715 break; /* == ignore */
2716 mtx_unlock(&ps->ps_mtx);
2717 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2718 &p->p_mtx.lock_object, "Catching SIGSTOP");
2719 p->p_flag |= P_STOPPED_SIG;
2722 sig_suspend_threads(td, p, 0);
2723 thread_suspend_switch(td);
2725 mtx_lock(&ps->ps_mtx);
2727 } else if (prop & SA_IGNORE) {
2729 * Except for SIGCONT, shouldn't get here.
2730 * Default action is to ignore; drop it.
2732 break; /* == ignore */
2737 case (intptr_t)SIG_IGN:
2739 * Masking above should prevent us ever trying
2740 * to take action on an ignored signal other
2741 * than SIGCONT, unless process is traced.
2743 if ((prop & SA_CONT) == 0 &&
2744 (p->p_flag & P_TRACED) == 0)
2745 printf("issignal\n");
2746 break; /* == ignore */
2750 * This signal has an action, let
2751 * postsig() process it.
2755 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2756 sigqueue_delete(&p->p_sigqueue, sig);
2762 thread_stopped(struct proc *p)
2766 PROC_LOCK_ASSERT(p, MA_OWNED);
2767 PROC_SLOCK_ASSERT(p, MA_OWNED);
2771 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2773 p->p_flag &= ~P_WAITED;
2774 PROC_LOCK(p->p_pptr);
2775 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2776 CLD_TRAPPED : CLD_STOPPED);
2777 PROC_UNLOCK(p->p_pptr);
2783 * Take the action for the specified signal
2784 * from the current set of pending signals.
2790 struct thread *td = curthread;
2791 register struct proc *p = td->td_proc;
2795 sigset_t returnmask, mask;
2797 KASSERT(sig != 0, ("postsig"));
2799 PROC_LOCK_ASSERT(p, MA_OWNED);
2801 mtx_assert(&ps->ps_mtx, MA_OWNED);
2802 ksiginfo_init(&ksi);
2803 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2804 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2806 ksi.ksi_signo = sig;
2807 if (ksi.ksi_code == SI_TIMER)
2808 itimer_accept(p, ksi.ksi_timerid, &ksi);
2809 action = ps->ps_sigact[_SIG_IDX(sig)];
2811 if (KTRPOINT(td, KTR_PSIG))
2812 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2813 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2815 if (p->p_stops & S_SIG) {
2816 mtx_unlock(&ps->ps_mtx);
2817 stopevent(p, S_SIG, sig);
2818 mtx_lock(&ps->ps_mtx);
2821 if (action == SIG_DFL) {
2823 * Default action, where the default is to kill
2824 * the process. (Other cases were ignored above.)
2826 mtx_unlock(&ps->ps_mtx);
2831 * If we get here, the signal must be caught.
2833 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2834 ("postsig action"));
2836 * Set the new mask value and also defer further
2837 * occurrences of this signal.
2839 * Special case: user has done a sigsuspend. Here the
2840 * current mask is not of interest, but rather the
2841 * mask from before the sigsuspend is what we want
2842 * restored after the signal processing is completed.
2844 if (td->td_pflags & TDP_OLDMASK) {
2845 returnmask = td->td_oldsigmask;
2846 td->td_pflags &= ~TDP_OLDMASK;
2848 returnmask = td->td_sigmask;
2850 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2851 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2852 SIGADDSET(mask, sig);
2853 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2854 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2856 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2858 * See kern_sigaction() for origin of this code.
2860 SIGDELSET(ps->ps_sigcatch, sig);
2861 if (sig != SIGCONT &&
2862 sigprop(sig) & SA_IGNORE)
2863 SIGADDSET(ps->ps_sigignore, sig);
2864 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2866 td->td_ru.ru_nsignals++;
2867 if (p->p_sig == sig) {
2871 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2877 * Kill the current process for stated reason.
2885 PROC_LOCK_ASSERT(p, MA_OWNED);
2886 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
2888 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
2889 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2890 p->p_flag |= P_WKILLED;
2891 kern_psignal(p, SIGKILL);
2895 * Force the current process to exit with the specified signal, dumping core
2896 * if appropriate. We bypass the normal tests for masked and caught signals,
2897 * allowing unrecoverable failures to terminate the process without changing
2898 * signal state. Mark the accounting record with the signal termination.
2899 * If dumping core, save the signal number for the debugger. Calls exit and
2907 struct proc *p = td->td_proc;
2909 PROC_LOCK_ASSERT(p, MA_OWNED);
2910 p->p_acflag |= AXSIG;
2912 * We must be single-threading to generate a core dump. This
2913 * ensures that the registers in the core file are up-to-date.
2914 * Also, the ELF dump handler assumes that the thread list doesn't
2915 * change out from under it.
2917 * XXX If another thread attempts to single-thread before us
2918 * (e.g. via fork()), we won't get a dump at all.
2920 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2923 * Log signals which would cause core dumps
2924 * (Log as LOG_INFO to appease those who don't want
2926 * XXX : Todo, as well as euid, write out ruid too
2927 * Note that coredump() drops proc lock.
2929 if (coredump(td) == 0)
2931 if (kern_logsigexit)
2933 "pid %d (%s), uid %d: exited on signal %d%s\n",
2934 p->p_pid, p->p_comm,
2935 td->td_ucred ? td->td_ucred->cr_uid : -1,
2937 sig & WCOREFLAG ? " (core dumped)" : "");
2940 exit1(td, W_EXITCODE(0, sig));
2945 * Send queued SIGCHLD to parent when child process's state
2949 sigparent(struct proc *p, int reason, int status)
2951 PROC_LOCK_ASSERT(p, MA_OWNED);
2952 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2954 if (p->p_ksi != NULL) {
2955 p->p_ksi->ksi_signo = SIGCHLD;
2956 p->p_ksi->ksi_code = reason;
2957 p->p_ksi->ksi_status = status;
2958 p->p_ksi->ksi_pid = p->p_pid;
2959 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2960 if (KSI_ONQ(p->p_ksi))
2963 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2967 childproc_jobstate(struct proc *p, int reason, int status)
2971 PROC_LOCK_ASSERT(p, MA_OWNED);
2972 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2975 * Wake up parent sleeping in kern_wait(), also send
2976 * SIGCHLD to parent, but SIGCHLD does not guarantee
2977 * that parent will awake, because parent may masked
2980 p->p_pptr->p_flag |= P_STATCHILD;
2983 ps = p->p_pptr->p_sigacts;
2984 mtx_lock(&ps->ps_mtx);
2985 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2986 mtx_unlock(&ps->ps_mtx);
2987 sigparent(p, reason, status);
2989 mtx_unlock(&ps->ps_mtx);
2993 childproc_stopped(struct proc *p, int reason)
2995 childproc_jobstate(p, reason, p->p_xstat);
2999 childproc_continued(struct proc *p)
3001 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3005 childproc_exited(struct proc *p)
3008 int status = p->p_xstat; /* convert to int */
3010 reason = CLD_EXITED;
3011 if (WCOREDUMP(status))
3012 reason = CLD_DUMPED;
3013 else if (WIFSIGNALED(status))
3014 reason = CLD_KILLED;
3016 * XXX avoid calling wakeup(p->p_pptr), the work is
3019 sigparent(p, reason, status);
3023 * We only have 1 character for the core count in the format
3024 * string, so the range will be 0-9
3026 #define MAX_NUM_CORES 10
3027 static int num_cores = 5;
3030 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3035 new_val = num_cores;
3036 error = sysctl_handle_int(oidp, &new_val, 0, req);
3037 if (error != 0 || req->newptr == NULL)
3039 if (new_val > MAX_NUM_CORES)
3040 new_val = MAX_NUM_CORES;
3043 num_cores = new_val;
3046 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3047 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3049 #if defined(COMPRESS_USER_CORES)
3050 int compress_user_cores = 1;
3051 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
3052 &compress_user_cores, 0, "Compression of user corefiles");
3054 int compress_user_cores_gzlevel = -1; /* default level */
3055 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
3056 &compress_user_cores_gzlevel, -1, "Corefile gzip compression level");
3058 #define GZ_SUFFIX ".gz"
3059 #define GZ_SUFFIX_LEN 3
3062 static char corefilename[MAXPATHLEN] = {"%N.core"};
3063 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3064 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3065 sizeof(corefilename), "Process corefile name format string");
3068 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3069 * Expand the name described in corefilename, using name, uid, and pid
3070 * and open/create core file.
3071 * corefilename is a printf-like string, with three format specifiers:
3072 * %N name of process ("name")
3073 * %P process id (pid)
3075 * For example, "%N.core" is the default; they can be disabled completely
3076 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3077 * This is controlled by the sysctl variable kern.corefile (see above).
3080 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3081 int compress, struct vnode **vpp, char **namep)
3083 struct nameidata nd;
3086 char *hostname, *name;
3087 int indexpos, i, error, cmode, flags, oflags;
3090 format = corefilename;
3091 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3093 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3094 for (i = 0; format[i] != '\0'; i++) {
3095 switch (format[i]) {
3096 case '%': /* Format character */
3098 switch (format[i]) {
3100 sbuf_putc(&sb, '%');
3102 case 'H': /* hostname */
3103 if (hostname == NULL) {
3104 hostname = malloc(MAXHOSTNAMELEN,
3107 getcredhostname(td->td_ucred, hostname,
3109 sbuf_printf(&sb, "%s", hostname);
3111 case 'I': /* autoincrementing index */
3112 sbuf_printf(&sb, "0");
3113 indexpos = sbuf_len(&sb) - 1;
3115 case 'N': /* process name */
3116 sbuf_printf(&sb, "%s", comm);
3118 case 'P': /* process id */
3119 sbuf_printf(&sb, "%u", pid);
3121 case 'U': /* user id */
3122 sbuf_printf(&sb, "%u", uid);
3126 "Unknown format character %c in "
3127 "corename `%s'\n", format[i], format);
3132 sbuf_putc(&sb, format[i]);
3135 free(hostname, M_TEMP);
3136 #ifdef COMPRESS_USER_CORES
3138 sbuf_printf(&sb, GZ_SUFFIX);
3140 if (sbuf_error(&sb) != 0) {
3141 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3142 "long\n", (long)pid, comm, (u_long)uid);
3150 cmode = S_IRUSR | S_IWUSR;
3151 oflags = VN_OPEN_NOAUDIT | (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3154 * If the core format has a %I in it, then we need to check
3155 * for existing corefiles before returning a name.
3156 * To do this we iterate over 0..num_cores to find a
3157 * non-existing core file name to use.
3159 if (indexpos != -1) {
3160 for (i = 0; i < num_cores; i++) {
3161 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3162 name[indexpos] = '0' + i;
3163 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3164 error = vn_open_cred(&nd, &flags, cmode, oflags,
3165 td->td_ucred, NULL);
3167 if (error == EEXIST)
3170 "pid %d (%s), uid (%u): Path `%s' failed "
3171 "on initial open test, error = %d\n",
3172 pid, comm, uid, name, error);
3178 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3179 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3180 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3184 audit_proc_coredump(td, name, error);
3189 NDFREE(&nd, NDF_ONLY_PNBUF);
3196 * Dump a process' core. The main routine does some
3197 * policy checking, and creates the name of the coredump;
3198 * then it passes on a vnode and a size limit to the process-specific
3199 * coredump routine if there is one; if there _is not_ one, it returns
3200 * ENOSYS; otherwise it returns the error from the process-specific routine.
3204 coredump(struct thread *td)
3206 struct proc *p = td->td_proc;
3207 struct ucred *cred = td->td_ucred;
3211 int error, error1, locked;
3213 char *name; /* name of corefile */
3217 #ifdef COMPRESS_USER_CORES
3218 compress = compress_user_cores;
3222 PROC_LOCK_ASSERT(p, MA_OWNED);
3223 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3224 _STOPEVENT(p, S_CORE, 0);
3226 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0)) {
3232 * Note that the bulk of limit checking is done after
3233 * the corefile is created. The exception is if the limit
3234 * for corefiles is 0, in which case we don't bother
3235 * creating the corefile at all. This layout means that
3236 * a corefile is truncated instead of not being created,
3237 * if it is larger than the limit.
3239 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3240 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3247 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td, compress,
3252 /* Don't dump to non-regular files or files with links. */
3253 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3254 vattr.va_nlink != 1) {
3261 lf.l_whence = SEEK_SET;
3264 lf.l_type = F_WRLCK;
3265 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3267 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3268 lf.l_type = F_UNLCK;
3270 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3271 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3273 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3280 if (set_core_nodump_flag)
3281 vattr.va_flags = UF_NODUMP;
3282 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3283 VOP_SETATTR(vp, &vattr, cred);
3285 vn_finished_write(mp);
3287 p->p_acflag |= ACORE;
3290 if (p->p_sysent->sv_coredump != NULL) {
3291 error = p->p_sysent->sv_coredump(td, vp, limit,
3292 compress ? IMGACT_CORE_COMPRESS : 0);
3298 lf.l_type = F_UNLCK;
3299 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3302 error1 = vn_close(vp, FWRITE, cred, td);
3307 audit_proc_coredump(td, name, error);
3314 * Nonexistent system call-- signal process (may want to handle it). Flag
3315 * error in case process won't see signal immediately (blocked or ignored).
3317 #ifndef _SYS_SYSPROTO_H_
3326 struct nosys_args *args;
3328 struct proc *p = td->td_proc;
3331 tdsignal(td, SIGSYS);
3337 * Send a SIGIO or SIGURG signal to a process or process group using stored
3338 * credentials rather than those of the current process.
3341 pgsigio(sigiop, sig, checkctty)
3342 struct sigio **sigiop;
3346 struct sigio *sigio;
3348 ksiginfo_init(&ksi);
3349 ksi.ksi_signo = sig;
3350 ksi.ksi_code = SI_KERNEL;
3354 if (sigio == NULL) {
3358 if (sigio->sio_pgid > 0) {
3359 PROC_LOCK(sigio->sio_proc);
3360 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3361 kern_psignal(sigio->sio_proc, sig);
3362 PROC_UNLOCK(sigio->sio_proc);
3363 } else if (sigio->sio_pgid < 0) {
3366 PGRP_LOCK(sigio->sio_pgrp);
3367 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3369 if (p->p_state == PRS_NORMAL &&
3370 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3371 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3372 kern_psignal(p, sig);
3375 PGRP_UNLOCK(sigio->sio_pgrp);
3381 filt_sigattach(struct knote *kn)
3383 struct proc *p = curproc;
3385 kn->kn_ptr.p_proc = p;
3386 kn->kn_flags |= EV_CLEAR; /* automatically set */
3388 knlist_add(&p->p_klist, kn, 0);
3394 filt_sigdetach(struct knote *kn)
3396 struct proc *p = kn->kn_ptr.p_proc;
3398 knlist_remove(&p->p_klist, kn, 0);
3402 * signal knotes are shared with proc knotes, so we apply a mask to
3403 * the hint in order to differentiate them from process hints. This
3404 * could be avoided by using a signal-specific knote list, but probably
3405 * isn't worth the trouble.
3408 filt_signal(struct knote *kn, long hint)
3411 if (hint & NOTE_SIGNAL) {
3412 hint &= ~NOTE_SIGNAL;
3414 if (kn->kn_id == hint)
3417 return (kn->kn_data != 0);
3425 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3427 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3432 sigacts_free(struct sigacts *ps)
3435 mtx_lock(&ps->ps_mtx);
3437 if (ps->ps_refcnt == 0) {
3438 mtx_destroy(&ps->ps_mtx);
3439 free(ps, M_SUBPROC);
3441 mtx_unlock(&ps->ps_mtx);
3445 sigacts_hold(struct sigacts *ps)
3447 mtx_lock(&ps->ps_mtx);
3449 mtx_unlock(&ps->ps_mtx);
3454 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3457 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3458 mtx_lock(&src->ps_mtx);
3459 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3460 mtx_unlock(&src->ps_mtx);
3464 sigacts_shared(struct sigacts *ps)
3468 mtx_lock(&ps->ps_mtx);
3469 shared = ps->ps_refcnt > 1;
3470 mtx_unlock(&ps->ps_mtx);