2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
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4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
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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 <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/signalvar.h>
47 #include <sys/vnode.h>
49 #include <sys/condvar.h>
50 #include <sys/event.h>
51 #include <sys/fcntl.h>
52 #include <sys/kernel.h>
54 #include <sys/ktrace.h>
56 #include <sys/malloc.h>
57 #include <sys/mutex.h>
58 #include <sys/namei.h>
60 #include <sys/posix4.h>
61 #include <sys/pioctl.h>
62 #include <sys/resourcevar.h>
65 #include <sys/sleepqueue.h>
69 #include <sys/syscallsubr.h>
70 #include <sys/sysctl.h>
71 #include <sys/sysent.h>
72 #include <sys/syslog.h>
73 #include <sys/sysproto.h>
74 #include <sys/timers.h>
75 #include <sys/unistd.h>
78 #include <vm/vm_extern.h>
81 #include <machine/cpu.h>
83 #include <security/audit/audit.h>
85 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
87 SDT_PROVIDER_DECLARE(proc);
88 SDT_PROBE_DEFINE(proc, kernel, , signal_send);
89 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 0, "struct thread *");
90 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 1, "struct proc *");
91 SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 2, "int");
92 SDT_PROBE_DEFINE(proc, kernel, , signal_clear);
93 SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 0, "int");
94 SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 1, "ksiginfo_t *");
95 SDT_PROBE_DEFINE(proc, kernel, , signal_discard);
96 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 0, "struct thread *");
97 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 1, "struct proc *");
98 SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 2, "int");
100 static int coredump(struct thread *);
101 static char *expand_name(const char *, uid_t, pid_t);
102 static int killpg1(struct thread *td, int sig, int pgid, int all);
103 static int issignal(struct thread *p);
104 static int sigprop(int sig);
105 static void tdsigwakeup(struct thread *, int, sig_t, int);
106 static void sig_suspend_threads(struct thread *, struct proc *, int);
107 static int filt_sigattach(struct knote *kn);
108 static void filt_sigdetach(struct knote *kn);
109 static int filt_signal(struct knote *kn, long hint);
110 static struct thread *sigtd(struct proc *p, int sig, int prop);
111 static void sigqueue_start(void);
113 static uma_zone_t ksiginfo_zone = NULL;
114 struct filterops sig_filtops =
115 { 0, filt_sigattach, filt_sigdetach, filt_signal };
117 int kern_logsigexit = 1;
118 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
120 "Log processes quitting on abnormal signals to syslog(3)");
122 static int kern_forcesigexit = 1;
123 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
124 &kern_forcesigexit, 0, "Force trap signal to be handled");
126 SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0, "POSIX real time signal");
128 static int max_pending_per_proc = 128;
129 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
130 &max_pending_per_proc, 0, "Max pending signals per proc");
132 static int preallocate_siginfo = 1024;
133 TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
134 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
135 &preallocate_siginfo, 0, "Preallocated signal memory size");
137 static int signal_overflow = 0;
138 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
139 &signal_overflow, 0, "Number of signals overflew");
141 static int signal_alloc_fail = 0;
142 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
143 &signal_alloc_fail, 0, "signals failed to be allocated");
145 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
148 * Policy -- Can ucred cr1 send SIGIO to process cr2?
149 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
150 * in the right situations.
152 #define CANSIGIO(cr1, cr2) \
153 ((cr1)->cr_uid == 0 || \
154 (cr1)->cr_ruid == (cr2)->cr_ruid || \
155 (cr1)->cr_uid == (cr2)->cr_ruid || \
156 (cr1)->cr_ruid == (cr2)->cr_uid || \
157 (cr1)->cr_uid == (cr2)->cr_uid)
160 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
161 &sugid_coredump, 0, "Enable coredumping set user/group ID processes");
163 static int do_coredump = 1;
164 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
165 &do_coredump, 0, "Enable/Disable coredumps");
167 static int set_core_nodump_flag = 0;
168 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
169 0, "Enable setting the NODUMP flag on coredump files");
172 * Signal properties and actions.
173 * The array below categorizes the signals and their default actions
174 * according to the following properties:
176 #define SA_KILL 0x01 /* terminates process by default */
177 #define SA_CORE 0x02 /* ditto and coredumps */
178 #define SA_STOP 0x04 /* suspend process */
179 #define SA_TTYSTOP 0x08 /* ditto, from tty */
180 #define SA_IGNORE 0x10 /* ignore by default */
181 #define SA_CONT 0x20 /* continue if suspended */
182 #define SA_CANTMASK 0x40 /* non-maskable, catchable */
183 #define SA_PROC 0x80 /* deliverable to any thread */
185 static int sigproptbl[NSIG] = {
186 SA_KILL|SA_PROC, /* SIGHUP */
187 SA_KILL|SA_PROC, /* SIGINT */
188 SA_KILL|SA_CORE|SA_PROC, /* SIGQUIT */
189 SA_KILL|SA_CORE, /* SIGILL */
190 SA_KILL|SA_CORE, /* SIGTRAP */
191 SA_KILL|SA_CORE, /* SIGABRT */
192 SA_KILL|SA_CORE|SA_PROC, /* SIGEMT */
193 SA_KILL|SA_CORE, /* SIGFPE */
194 SA_KILL|SA_PROC, /* SIGKILL */
195 SA_KILL|SA_CORE, /* SIGBUS */
196 SA_KILL|SA_CORE, /* SIGSEGV */
197 SA_KILL|SA_CORE, /* SIGSYS */
198 SA_KILL|SA_PROC, /* SIGPIPE */
199 SA_KILL|SA_PROC, /* SIGALRM */
200 SA_KILL|SA_PROC, /* SIGTERM */
201 SA_IGNORE|SA_PROC, /* SIGURG */
202 SA_STOP|SA_PROC, /* SIGSTOP */
203 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTSTP */
204 SA_IGNORE|SA_CONT|SA_PROC, /* SIGCONT */
205 SA_IGNORE|SA_PROC, /* SIGCHLD */
206 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTIN */
207 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTOU */
208 SA_IGNORE|SA_PROC, /* SIGIO */
209 SA_KILL, /* SIGXCPU */
210 SA_KILL, /* SIGXFSZ */
211 SA_KILL|SA_PROC, /* SIGVTALRM */
212 SA_KILL|SA_PROC, /* SIGPROF */
213 SA_IGNORE|SA_PROC, /* SIGWINCH */
214 SA_IGNORE|SA_PROC, /* SIGINFO */
215 SA_KILL|SA_PROC, /* SIGUSR1 */
216 SA_KILL|SA_PROC, /* SIGUSR2 */
222 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
223 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
224 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
225 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
226 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
227 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
231 ksiginfo_alloc(int wait)
238 if (ksiginfo_zone != NULL)
239 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
244 ksiginfo_free(ksiginfo_t *ksi)
246 uma_zfree(ksiginfo_zone, ksi);
250 ksiginfo_tryfree(ksiginfo_t *ksi)
252 if (!(ksi->ksi_flags & KSI_EXT)) {
253 uma_zfree(ksiginfo_zone, ksi);
260 sigqueue_init(sigqueue_t *list, struct proc *p)
262 SIGEMPTYSET(list->sq_signals);
263 SIGEMPTYSET(list->sq_kill);
264 TAILQ_INIT(&list->sq_list);
266 list->sq_flags = SQ_INIT;
270 * Get a signal's ksiginfo.
272 * 0 - signal not found
273 * others - signal number
276 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
278 struct proc *p = sq->sq_proc;
279 struct ksiginfo *ksi, *next;
282 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
284 if (!SIGISMEMBER(sq->sq_signals, signo))
287 if (SIGISMEMBER(sq->sq_kill, signo)) {
289 SIGDELSET(sq->sq_kill, signo);
292 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
293 if (ksi->ksi_signo == signo) {
295 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
296 ksi->ksi_sigq = NULL;
297 ksiginfo_copy(ksi, si);
298 if (ksiginfo_tryfree(ksi) && p != NULL)
307 SIGDELSET(sq->sq_signals, signo);
308 si->ksi_signo = signo;
313 sigqueue_take(ksiginfo_t *ksi)
319 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
323 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
324 ksi->ksi_sigq = NULL;
325 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
328 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
329 kp = TAILQ_NEXT(kp, ksi_link)) {
330 if (kp->ksi_signo == ksi->ksi_signo)
333 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
334 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
338 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
340 struct proc *p = sq->sq_proc;
341 struct ksiginfo *ksi;
344 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
346 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
347 SIGADDSET(sq->sq_kill, signo);
351 /* directly insert the ksi, don't copy it */
352 if (si->ksi_flags & KSI_INS) {
353 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
358 if (__predict_false(ksiginfo_zone == NULL)) {
359 SIGADDSET(sq->sq_kill, signo);
363 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
366 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
372 ksiginfo_copy(si, ksi);
373 ksi->ksi_signo = signo;
374 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
378 if ((si->ksi_flags & KSI_TRAP) != 0) {
380 SIGADDSET(sq->sq_kill, signo);
389 SIGADDSET(sq->sq_signals, signo);
394 sigqueue_flush(sigqueue_t *sq)
396 struct proc *p = sq->sq_proc;
399 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
402 PROC_LOCK_ASSERT(p, MA_OWNED);
404 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
405 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
406 ksi->ksi_sigq = NULL;
407 if (ksiginfo_tryfree(ksi) && p != NULL)
411 SIGEMPTYSET(sq->sq_signals);
412 SIGEMPTYSET(sq->sq_kill);
416 sigqueue_collect_set(sigqueue_t *sq, sigset_t *set)
420 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
422 TAILQ_FOREACH(ksi, &sq->sq_list, ksi_link)
423 SIGADDSET(*set, ksi->ksi_signo);
424 SIGSETOR(*set, sq->sq_kill);
428 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, sigset_t *setp)
431 struct proc *p1, *p2;
432 ksiginfo_t *ksi, *next;
434 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
435 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
437 * make a copy, this allows setp to point to src or dst
438 * sq_signals without trouble.
443 /* Move siginfo to target list */
444 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
445 if (SIGISMEMBER(set, ksi->ksi_signo)) {
446 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
449 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
456 /* Move pending bits to target list */
459 SIGSETOR(dst->sq_kill, tmp);
460 SIGSETNAND(src->sq_kill, tmp);
462 tmp = src->sq_signals;
464 SIGSETOR(dst->sq_signals, tmp);
465 SIGSETNAND(src->sq_signals, tmp);
467 /* Finally, rescan src queue and set pending bits for it */
468 sigqueue_collect_set(src, &src->sq_signals);
472 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
477 SIGADDSET(set, signo);
478 sigqueue_move_set(src, dst, &set);
482 sigqueue_delete_set(sigqueue_t *sq, sigset_t *set)
484 struct proc *p = sq->sq_proc;
485 ksiginfo_t *ksi, *next;
487 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
489 /* Remove siginfo queue */
490 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
491 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
492 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
493 ksi->ksi_sigq = NULL;
494 if (ksiginfo_tryfree(ksi) && p != NULL)
498 SIGSETNAND(sq->sq_kill, *set);
499 SIGSETNAND(sq->sq_signals, *set);
500 /* Finally, rescan queue and set pending bits for it */
501 sigqueue_collect_set(sq, &sq->sq_signals);
505 sigqueue_delete(sigqueue_t *sq, int signo)
510 SIGADDSET(set, signo);
511 sigqueue_delete_set(sq, &set);
514 /* Remove a set of signals for a process */
516 sigqueue_delete_set_proc(struct proc *p, sigset_t *set)
521 PROC_LOCK_ASSERT(p, MA_OWNED);
523 sigqueue_init(&worklist, NULL);
524 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
526 FOREACH_THREAD_IN_PROC(p, td0)
527 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
529 sigqueue_flush(&worklist);
533 sigqueue_delete_proc(struct proc *p, int signo)
538 SIGADDSET(set, signo);
539 sigqueue_delete_set_proc(p, &set);
543 sigqueue_delete_stopmask_proc(struct proc *p)
548 SIGADDSET(set, SIGSTOP);
549 SIGADDSET(set, SIGTSTP);
550 SIGADDSET(set, SIGTTIN);
551 SIGADDSET(set, SIGTTOU);
552 sigqueue_delete_set_proc(p, &set);
556 * Determine signal that should be delivered to process p, the current
557 * process, 0 if none. If there is a pending stop signal with default
558 * action, the process stops in issignal().
561 cursig(struct thread *td)
563 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
564 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
565 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
566 return (SIGPENDING(td) ? issignal(td) : 0);
570 * Arrange for ast() to handle unmasked pending signals on return to user
571 * mode. This must be called whenever a signal is added to td_sigqueue or
572 * unmasked in td_sigmask.
575 signotify(struct thread *td)
582 PROC_LOCK_ASSERT(p, MA_OWNED);
585 * If our mask changed we may have to move signal that were
586 * previously masked by all threads to our sigqueue.
588 set = p->p_sigqueue.sq_signals;
589 SIGSETNAND(set, td->td_sigmask);
590 if (! SIGISEMPTY(set))
591 sigqueue_move_set(&p->p_sigqueue, &td->td_sigqueue, &set);
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;
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(td, how, set, oset, old)
976 sigset_t *set, *oset;
981 PROC_LOCK(td->td_proc);
983 *oset = td->td_sigmask;
990 SIGSETOR(td->td_sigmask, *set);
993 SIGSETNAND(td->td_sigmask, *set);
999 SIGSETLO(td->td_sigmask, *set);
1001 td->td_sigmask = *set;
1009 PROC_UNLOCK(td->td_proc);
1013 #ifndef _SYS_SYSPROTO_H_
1014 struct sigprocmask_args {
1016 const sigset_t *set;
1021 sigprocmask(td, uap)
1022 register struct thread *td;
1023 struct sigprocmask_args *uap;
1026 sigset_t *setp, *osetp;
1029 setp = (uap->set != NULL) ? &set : NULL;
1030 osetp = (uap->oset != NULL) ? &oset : NULL;
1032 error = copyin(uap->set, setp, sizeof(set));
1036 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1037 if (osetp && !error) {
1038 error = copyout(osetp, uap->oset, sizeof(oset));
1043 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1044 #ifndef _SYS_SYSPROTO_H_
1045 struct osigprocmask_args {
1051 osigprocmask(td, uap)
1052 register struct thread *td;
1053 struct osigprocmask_args *uap;
1058 OSIG2SIG(uap->mask, set);
1059 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1060 SIG2OSIG(oset, td->td_retval[0]);
1063 #endif /* COMPAT_43 */
1066 sigwait(struct thread *td, struct sigwait_args *uap)
1072 error = copyin(uap->set, &set, sizeof(set));
1074 td->td_retval[0] = error;
1078 error = kern_sigtimedwait(td, set, &ksi, NULL);
1080 if (error == ERESTART)
1082 td->td_retval[0] = error;
1086 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1087 td->td_retval[0] = error;
1092 sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1095 struct timespec *timeout;
1101 error = copyin(uap->timeout, &ts, sizeof(ts));
1109 error = copyin(uap->set, &set, sizeof(set));
1113 error = kern_sigtimedwait(td, set, &ksi, timeout);
1118 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1121 td->td_retval[0] = ksi.ksi_signo;
1126 sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1132 error = copyin(uap->set, &set, sizeof(set));
1136 error = kern_sigtimedwait(td, set, &ksi, NULL);
1141 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1144 td->td_retval[0] = ksi.ksi_signo;
1149 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1150 struct timespec *timeout)
1155 int error, sig, hz, i, timevalid = 0;
1156 struct timespec rts, ets, ts;
1164 SIG_CANTMASK(waitset);
1168 savedmask = td->td_sigmask;
1170 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1172 getnanouptime(&rts);
1174 timespecadd(&ets, timeout);
1179 for (i = 1; i <= _SIG_MAXSIG; ++i) {
1180 if (!SIGISMEMBER(waitset, i))
1182 if (!SIGISMEMBER(td->td_sigqueue.sq_signals, i)) {
1183 if (SIGISMEMBER(p->p_sigqueue.sq_signals, i)) {
1184 sigqueue_move(&p->p_sigqueue,
1185 &td->td_sigqueue, i);
1190 SIGFILLSET(td->td_sigmask);
1191 SIG_CANTMASK(td->td_sigmask);
1192 SIGDELSET(td->td_sigmask, i);
1193 mtx_lock(&ps->ps_mtx);
1195 mtx_unlock(&ps->ps_mtx);
1200 * Because cursig() may have stopped current thread,
1201 * after it is resumed, things may have already been
1202 * changed, it should rescan any pending signals.
1212 * POSIX says this must be checked after looking for pending
1220 getnanouptime(&rts);
1221 if (timespeccmp(&rts, &ets, >=)) {
1226 timespecsub(&ts, &rts);
1227 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1232 td->td_sigmask = savedmask;
1233 SIGSETNAND(td->td_sigmask, waitset);
1235 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz);
1237 if (error == ERESTART) {
1238 /* timeout can not be restarted. */
1240 } else if (error == EAGAIN) {
1241 /* will calculate timeout by ourself. */
1248 td->td_sigmask = savedmask;
1252 sigqueue_get(&td->td_sigqueue, sig, ksi);
1253 ksi->ksi_signo = sig;
1255 SDT_PROBE(proc, kernel, , signal_clear, sig, ksi, 0, 0, 0);
1257 if (ksi->ksi_code == SI_TIMER)
1258 itimer_accept(p, ksi->ksi_timerid, ksi);
1262 if (KTRPOINT(td, KTR_PSIG)) {
1265 mtx_lock(&ps->ps_mtx);
1266 action = ps->ps_sigact[_SIG_IDX(sig)];
1267 mtx_unlock(&ps->ps_mtx);
1268 ktrpsig(sig, action, &td->td_sigmask, 0);
1278 #ifndef _SYS_SYSPROTO_H_
1279 struct sigpending_args {
1286 struct sigpending_args *uap;
1288 struct proc *p = td->td_proc;
1292 pending = p->p_sigqueue.sq_signals;
1293 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1295 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1298 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1299 #ifndef _SYS_SYSPROTO_H_
1300 struct osigpending_args {
1305 osigpending(td, uap)
1307 struct osigpending_args *uap;
1309 struct proc *p = td->td_proc;
1313 pending = p->p_sigqueue.sq_signals;
1314 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1316 SIG2OSIG(pending, td->td_retval[0]);
1319 #endif /* COMPAT_43 */
1321 #if defined(COMPAT_43)
1323 * Generalized interface signal handler, 4.3-compatible.
1325 #ifndef _SYS_SYSPROTO_H_
1326 struct osigvec_args {
1336 register struct osigvec_args *uap;
1339 struct sigaction nsa, osa;
1340 register struct sigaction *nsap, *osap;
1343 if (uap->signum <= 0 || uap->signum >= ONSIG)
1345 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1346 osap = (uap->osv != NULL) ? &osa : NULL;
1348 error = copyin(uap->nsv, &vec, sizeof(vec));
1351 nsap->sa_handler = vec.sv_handler;
1352 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1353 nsap->sa_flags = vec.sv_flags;
1354 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1356 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1357 if (osap && !error) {
1358 vec.sv_handler = osap->sa_handler;
1359 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1360 vec.sv_flags = osap->sa_flags;
1361 vec.sv_flags &= ~SA_NOCLDWAIT;
1362 vec.sv_flags ^= SA_RESTART;
1363 error = copyout(&vec, uap->osv, sizeof(vec));
1368 #ifndef _SYS_SYSPROTO_H_
1369 struct osigblock_args {
1375 register struct thread *td;
1376 struct osigblock_args *uap;
1378 struct proc *p = td->td_proc;
1381 OSIG2SIG(uap->mask, set);
1384 SIG2OSIG(td->td_sigmask, td->td_retval[0]);
1385 SIGSETOR(td->td_sigmask, set);
1390 #ifndef _SYS_SYSPROTO_H_
1391 struct osigsetmask_args {
1396 osigsetmask(td, uap)
1398 struct osigsetmask_args *uap;
1400 struct proc *p = td->td_proc;
1403 OSIG2SIG(uap->mask, set);
1406 SIG2OSIG(td->td_sigmask, td->td_retval[0]);
1407 SIGSETLO(td->td_sigmask, set);
1412 #endif /* COMPAT_43 */
1415 * Suspend calling thread until signal, providing mask to be set in the
1418 #ifndef _SYS_SYSPROTO_H_
1419 struct sigsuspend_args {
1420 const sigset_t *sigmask;
1427 struct sigsuspend_args *uap;
1432 error = copyin(uap->sigmask, &mask, sizeof(mask));
1435 return (kern_sigsuspend(td, mask));
1439 kern_sigsuspend(struct thread *td, sigset_t mask)
1441 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 td->td_oldsigmask = td->td_sigmask;
1452 td->td_pflags |= TDP_OLDMASK;
1454 td->td_sigmask = mask;
1456 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0)
1459 /* always return EINTR rather than ERESTART... */
1463 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1465 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1466 * convention: libc stub passes mask, not pointer, to save a copyin.
1468 #ifndef _SYS_SYSPROTO_H_
1469 struct osigsuspend_args {
1475 osigsuspend(td, uap)
1477 struct osigsuspend_args *uap;
1479 struct proc *p = td->td_proc;
1483 td->td_oldsigmask = td->td_sigmask;
1484 td->td_pflags |= TDP_OLDMASK;
1485 OSIG2SIG(uap->mask, mask);
1487 SIGSETLO(td->td_sigmask, mask);
1489 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0)
1492 /* always return EINTR rather than ERESTART... */
1495 #endif /* COMPAT_43 */
1497 #if defined(COMPAT_43)
1498 #ifndef _SYS_SYSPROTO_H_
1499 struct osigstack_args {
1500 struct sigstack *nss;
1501 struct sigstack *oss;
1508 register struct osigstack_args *uap;
1510 struct sigstack nss, oss;
1513 if (uap->nss != NULL) {
1514 error = copyin(uap->nss, &nss, sizeof(nss));
1518 oss.ss_sp = td->td_sigstk.ss_sp;
1519 oss.ss_onstack = sigonstack(cpu_getstack(td));
1520 if (uap->nss != NULL) {
1521 td->td_sigstk.ss_sp = nss.ss_sp;
1522 td->td_sigstk.ss_size = 0;
1523 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1524 td->td_pflags |= TDP_ALTSTACK;
1526 if (uap->oss != NULL)
1527 error = copyout(&oss, uap->oss, sizeof(oss));
1531 #endif /* COMPAT_43 */
1533 #ifndef _SYS_SYSPROTO_H_
1534 struct sigaltstack_args {
1541 sigaltstack(td, uap)
1543 register struct sigaltstack_args *uap;
1548 if (uap->ss != NULL) {
1549 error = copyin(uap->ss, &ss, sizeof(ss));
1553 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1554 (uap->oss != NULL) ? &oss : NULL);
1557 if (uap->oss != NULL)
1558 error = copyout(&oss, uap->oss, sizeof(stack_t));
1563 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1565 struct proc *p = td->td_proc;
1568 oonstack = sigonstack(cpu_getstack(td));
1571 *oss = td->td_sigstk;
1572 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1573 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1579 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1581 if (!(ss->ss_flags & SS_DISABLE)) {
1582 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1585 td->td_sigstk = *ss;
1586 td->td_pflags |= TDP_ALTSTACK;
1588 td->td_pflags &= ~TDP_ALTSTACK;
1595 * Common code for kill process group/broadcast kill.
1596 * cp is calling process.
1599 killpg1(td, sig, pgid, all)
1600 register struct thread *td;
1603 register struct proc *p;
1611 sx_slock(&allproc_lock);
1612 FOREACH_PROC_IN_SYSTEM(p) {
1614 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1615 p == td->td_proc || p->p_state == PRS_NEW) {
1619 if (p_cansignal(td, p, sig) == 0) {
1626 sx_sunlock(&allproc_lock);
1628 sx_slock(&proctree_lock);
1631 * zero pgid means send to my process group.
1633 pgrp = td->td_proc->p_pgrp;
1636 pgrp = pgfind(pgid);
1638 sx_sunlock(&proctree_lock);
1642 sx_sunlock(&proctree_lock);
1643 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1645 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1646 p->p_state == PRS_NEW ) {
1650 if (p_cansignal(td, p, sig) == 0) {
1659 return (nfound ? 0 : ESRCH);
1662 #ifndef _SYS_SYSPROTO_H_
1671 register struct thread *td;
1672 register struct kill_args *uap;
1674 register struct proc *p;
1677 AUDIT_ARG(signum, uap->signum);
1678 AUDIT_ARG(pid, uap->pid);
1679 if ((u_int)uap->signum > _SIG_MAXSIG)
1683 /* kill single process */
1684 if ((p = pfind(uap->pid)) == NULL) {
1685 if ((p = zpfind(uap->pid)) == NULL)
1688 AUDIT_ARG(process, p);
1689 error = p_cansignal(td, p, uap->signum);
1690 if (error == 0 && uap->signum)
1691 psignal(p, uap->signum);
1696 case -1: /* broadcast signal */
1697 return (killpg1(td, uap->signum, 0, 1));
1698 case 0: /* signal own process group */
1699 return (killpg1(td, uap->signum, 0, 0));
1700 default: /* negative explicit process group */
1701 return (killpg1(td, uap->signum, -uap->pid, 0));
1706 #if defined(COMPAT_43)
1707 #ifndef _SYS_SYSPROTO_H_
1708 struct okillpg_args {
1717 register struct okillpg_args *uap;
1720 AUDIT_ARG(signum, uap->signum);
1721 AUDIT_ARG(pid, uap->pgid);
1722 if ((u_int)uap->signum > _SIG_MAXSIG)
1725 return (killpg1(td, uap->signum, uap->pgid, 0));
1727 #endif /* COMPAT_43 */
1729 #ifndef _SYS_SYSPROTO_H_
1730 struct sigqueue_args {
1733 /* union sigval */ void *value;
1737 sigqueue(struct thread *td, struct sigqueue_args *uap)
1743 if ((u_int)uap->signum > _SIG_MAXSIG)
1747 * Specification says sigqueue can only send signal to
1753 if ((p = pfind(uap->pid)) == NULL) {
1754 if ((p = zpfind(uap->pid)) == NULL)
1757 error = p_cansignal(td, p, uap->signum);
1758 if (error == 0 && uap->signum != 0) {
1759 ksiginfo_init(&ksi);
1760 ksi.ksi_signo = uap->signum;
1761 ksi.ksi_code = SI_QUEUE;
1762 ksi.ksi_pid = td->td_proc->p_pid;
1763 ksi.ksi_uid = td->td_ucred->cr_ruid;
1764 ksi.ksi_value.sival_ptr = uap->value;
1765 error = tdsignal(p, NULL, ksi.ksi_signo, &ksi);
1772 * Send a signal to a process group.
1781 sx_slock(&proctree_lock);
1782 pgrp = pgfind(pgid);
1783 sx_sunlock(&proctree_lock);
1785 pgsignal(pgrp, sig, 0);
1792 * Send a signal to a process group. If checktty is 1,
1793 * limit to members which have a controlling terminal.
1796 pgsignal(pgrp, sig, checkctty)
1800 register struct proc *p;
1803 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1804 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1806 if (checkctty == 0 || p->p_flag & P_CONTROLT)
1814 * Send a signal caused by a trap to the current thread. If it will be
1815 * caught immediately, deliver it with correct code. Otherwise, post it
1819 trapsignal(struct thread *td, ksiginfo_t *ksi)
1827 sig = ksi->ksi_signo;
1828 code = ksi->ksi_code;
1829 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1833 mtx_lock(&ps->ps_mtx);
1834 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1835 !SIGISMEMBER(td->td_sigmask, sig)) {
1836 td->td_ru.ru_nsignals++;
1838 if (KTRPOINT(curthread, KTR_PSIG))
1839 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1840 &td->td_sigmask, code);
1842 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1843 ksi, &td->td_sigmask);
1844 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
1845 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1846 SIGADDSET(td->td_sigmask, sig);
1847 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1849 * See kern_sigaction() for origin of this code.
1851 SIGDELSET(ps->ps_sigcatch, sig);
1852 if (sig != SIGCONT &&
1853 sigprop(sig) & SA_IGNORE)
1854 SIGADDSET(ps->ps_sigignore, sig);
1855 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1857 mtx_unlock(&ps->ps_mtx);
1860 * Avoid a possible infinite loop if the thread
1861 * masking the signal or process is ignoring the
1864 if (kern_forcesigexit &&
1865 (SIGISMEMBER(td->td_sigmask, sig) ||
1866 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1867 SIGDELSET(td->td_sigmask, sig);
1868 SIGDELSET(ps->ps_sigcatch, sig);
1869 SIGDELSET(ps->ps_sigignore, sig);
1870 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1872 mtx_unlock(&ps->ps_mtx);
1873 p->p_code = code; /* XXX for core dump/debugger */
1874 p->p_sig = sig; /* XXX to verify code */
1875 tdsignal(p, td, sig, ksi);
1880 static struct thread *
1881 sigtd(struct proc *p, int sig, int prop)
1883 struct thread *td, *signal_td;
1885 PROC_LOCK_ASSERT(p, MA_OWNED);
1888 * Check if current thread can handle the signal without
1889 * switching conetxt to another thread.
1891 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1894 FOREACH_THREAD_IN_PROC(p, td) {
1895 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1900 if (signal_td == NULL)
1901 signal_td = FIRST_THREAD_IN_PROC(p);
1906 * Send the signal to the process. If the signal has an action, the action
1907 * is usually performed by the target process rather than the caller; we add
1908 * the signal to the set of pending signals for the process.
1911 * o When a stop signal is sent to a sleeping process that takes the
1912 * default action, the process is stopped without awakening it.
1913 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1914 * regardless of the signal action (eg, blocked or ignored).
1916 * Other ignored signals are discarded immediately.
1918 * NB: This function may be entered from the debugger via the "kill" DDB
1919 * command. There is little that can be done to mitigate the possibly messy
1920 * side effects of this unwise possibility.
1923 psignal(struct proc *p, int sig)
1925 (void) tdsignal(p, NULL, sig, NULL);
1929 psignal_event(struct proc *p, struct sigevent *sigev, ksiginfo_t *ksi)
1931 struct thread *td = NULL;
1933 PROC_LOCK_ASSERT(p, MA_OWNED);
1935 KASSERT(!KSI_ONQ(ksi), ("psignal_event: ksi on queue"));
1938 * ksi_code and other fields should be set before
1939 * calling this function.
1941 ksi->ksi_signo = sigev->sigev_signo;
1942 ksi->ksi_value = sigev->sigev_value;
1943 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
1944 td = thread_find(p, sigev->sigev_notify_thread_id);
1948 return (tdsignal(p, td, ksi->ksi_signo, ksi));
1952 tdsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
1955 sigqueue_t *sigqueue;
1962 PROC_LOCK_ASSERT(p, MA_OWNED);
1964 if (!_SIG_VALID(sig))
1965 panic("tdsignal(): invalid signal %d", sig);
1967 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("tdsignal: ksi on queue"));
1970 * IEEE Std 1003.1-2001: return success when killing a zombie.
1972 if (p->p_state == PRS_ZOMBIE) {
1973 if (ksi && (ksi->ksi_flags & KSI_INS))
1974 ksiginfo_tryfree(ksi);
1979 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
1980 prop = sigprop(sig);
1983 * If the signal is blocked and not destined for this thread, then
1984 * assign it to the process so that we can find it later in the first
1985 * thread that unblocks it. Otherwise, assign it to this thread now.
1988 td = sigtd(p, sig, prop);
1989 if (SIGISMEMBER(td->td_sigmask, sig))
1990 sigqueue = &p->p_sigqueue;
1992 sigqueue = &td->td_sigqueue;
1994 KASSERT(td->td_proc == p, ("invalid thread"));
1995 sigqueue = &td->td_sigqueue;
1998 SDT_PROBE(proc, kernel, , signal_send, td, p, sig, 0, 0 );
2001 * If the signal is being ignored,
2002 * then we forget about it immediately.
2003 * (Note: we don't set SIGCONT in ps_sigignore,
2004 * and if it is set to SIG_IGN,
2005 * action will be SIG_DFL here.)
2007 mtx_lock(&ps->ps_mtx);
2008 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2009 SDT_PROBE(proc, kernel, , signal_discard, ps, td, sig, 0, 0 );
2011 mtx_unlock(&ps->ps_mtx);
2012 if (ksi && (ksi->ksi_flags & KSI_INS))
2013 ksiginfo_tryfree(ksi);
2016 if (SIGISMEMBER(td->td_sigmask, sig))
2018 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2022 if (SIGISMEMBER(ps->ps_sigintr, sig))
2026 mtx_unlock(&ps->ps_mtx);
2029 sigqueue_delete_stopmask_proc(p);
2030 else if (prop & SA_STOP) {
2032 * If sending a tty stop signal to a member of an orphaned
2033 * process group, discard the signal here if the action
2034 * is default; don't stop the process below if sleeping,
2035 * and don't clear any pending SIGCONT.
2037 if ((prop & SA_TTYSTOP) &&
2038 (p->p_pgrp->pg_jobc == 0) &&
2039 (action == SIG_DFL)) {
2040 if (ksi && (ksi->ksi_flags & KSI_INS))
2041 ksiginfo_tryfree(ksi);
2044 sigqueue_delete_proc(p, SIGCONT);
2045 if (p->p_flag & P_CONTINUED) {
2046 p->p_flag &= ~P_CONTINUED;
2047 PROC_LOCK(p->p_pptr);
2048 sigqueue_take(p->p_ksi);
2049 PROC_UNLOCK(p->p_pptr);
2053 ret = sigqueue_add(sigqueue, sig, ksi);
2058 * Defer further processing for signals which are held,
2059 * except that stopped processes must be continued by SIGCONT.
2061 if (action == SIG_HOLD &&
2062 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2065 * SIGKILL: Remove procfs STOPEVENTs.
2067 if (sig == SIGKILL) {
2068 /* from procfs_ioctl.c: PIOCBIC */
2070 /* from procfs_ioctl.c: PIOCCONT */
2075 * Some signals have a process-wide effect and a per-thread
2076 * component. Most processing occurs when the process next
2077 * tries to cross the user boundary, however there are some
2078 * times when processing needs to be done immediatly, such as
2079 * waking up threads so that they can cross the user boundary.
2080 * We try do the per-process part here.
2082 if (P_SHOULDSTOP(p)) {
2084 * The process is in stopped mode. All the threads should be
2085 * either winding down or already on the suspended queue.
2087 if (p->p_flag & P_TRACED) {
2089 * The traced process is already stopped,
2090 * so no further action is necessary.
2091 * No signal can restart us.
2096 if (sig == SIGKILL) {
2098 * SIGKILL sets process running.
2099 * It will die elsewhere.
2100 * All threads must be restarted.
2102 p->p_flag &= ~P_STOPPED_SIG;
2106 if (prop & SA_CONT) {
2108 * If SIGCONT is default (or ignored), we continue the
2109 * process but don't leave the signal in sigqueue as
2110 * it has no further action. If SIGCONT is held, we
2111 * continue the process and leave the signal in
2112 * sigqueue. If the process catches SIGCONT, let it
2113 * handle the signal itself. If it isn't waiting on
2114 * an event, it goes back to run state.
2115 * Otherwise, process goes back to sleep state.
2117 p->p_flag &= ~P_STOPPED_SIG;
2119 if (p->p_numthreads == p->p_suspcount) {
2121 p->p_flag |= P_CONTINUED;
2122 p->p_xstat = SIGCONT;
2123 PROC_LOCK(p->p_pptr);
2124 childproc_continued(p);
2125 PROC_UNLOCK(p->p_pptr);
2128 if (action == SIG_DFL) {
2129 thread_unsuspend(p);
2131 sigqueue_delete(sigqueue, sig);
2134 if (action == SIG_CATCH) {
2136 * The process wants to catch it so it needs
2137 * to run at least one thread, but which one?
2143 * The signal is not ignored or caught.
2145 thread_unsuspend(p);
2150 if (prop & SA_STOP) {
2152 * Already stopped, don't need to stop again
2153 * (If we did the shell could get confused).
2154 * Just make sure the signal STOP bit set.
2156 p->p_flag |= P_STOPPED_SIG;
2157 sigqueue_delete(sigqueue, sig);
2162 * All other kinds of signals:
2163 * If a thread is sleeping interruptibly, simulate a
2164 * wakeup so that when it is continued it will be made
2165 * runnable and can look at the signal. However, don't make
2166 * the PROCESS runnable, leave it stopped.
2167 * It may run a bit until it hits a thread_suspend_check().
2172 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2173 wakeup_swapper = sleepq_abort(td, intrval);
2180 * Mutexes are short lived. Threads waiting on them will
2181 * hit thread_suspend_check() soon.
2183 } else if (p->p_state == PRS_NORMAL) {
2184 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2185 tdsigwakeup(td, sig, action, intrval);
2189 MPASS(action == SIG_DFL);
2191 if (prop & SA_STOP) {
2192 if (p->p_flag & P_PPWAIT)
2194 p->p_flag |= P_STOPPED_SIG;
2197 sig_suspend_threads(td, p, 1);
2198 if (p->p_numthreads == p->p_suspcount) {
2200 * only thread sending signal to another
2201 * process can reach here, if thread is sending
2202 * signal to its process, because thread does
2203 * not suspend itself here, p_numthreads
2204 * should never be equal to p_suspcount.
2208 sigqueue_delete_proc(p, p->p_xstat);
2214 /* Not in "NORMAL" state. discard the signal. */
2215 sigqueue_delete(sigqueue, sig);
2220 * The process is not stopped so we need to apply the signal to all the
2224 tdsigwakeup(td, sig, action, intrval);
2226 thread_unsuspend(p);
2229 /* If we jump here, proc slock should not be owned. */
2230 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2235 * The force of a signal has been directed against a single
2236 * thread. We need to see what we can do about knocking it
2237 * out of any sleep it may be in etc.
2240 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2242 struct proc *p = td->td_proc;
2247 PROC_LOCK_ASSERT(p, MA_OWNED);
2248 prop = sigprop(sig);
2253 * Bring the priority of a thread up if we want it to get
2254 * killed in this lifetime.
2256 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2257 sched_prio(td, PUSER);
2258 if (TD_ON_SLEEPQ(td)) {
2260 * If thread is sleeping uninterruptibly
2261 * we can't interrupt the sleep... the signal will
2262 * be noticed when the process returns through
2263 * trap() or syscall().
2265 if ((td->td_flags & TDF_SINTR) == 0)
2268 * If SIGCONT is default (or ignored) and process is
2269 * asleep, we are finished; the process should not
2272 if ((prop & SA_CONT) && action == SIG_DFL) {
2275 sigqueue_delete(&p->p_sigqueue, sig);
2277 * It may be on either list in this state.
2278 * Remove from both for now.
2280 sigqueue_delete(&td->td_sigqueue, sig);
2285 * Give low priority threads a better chance to run.
2287 if (td->td_priority > PUSER)
2288 sched_prio(td, PUSER);
2290 wakeup_swapper = sleepq_abort(td, intrval);
2293 * Other states do nothing with the signal immediately,
2294 * other than kicking ourselves if we are running.
2295 * It will either never be noticed, or noticed very soon.
2298 if (TD_IS_RUNNING(td) && td != curthread)
2310 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2314 PROC_LOCK_ASSERT(p, MA_OWNED);
2315 PROC_SLOCK_ASSERT(p, MA_OWNED);
2317 FOREACH_THREAD_IN_PROC(p, td2) {
2319 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2320 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2321 (td2->td_flags & TDF_SINTR) &&
2322 !TD_IS_SUSPENDED(td2)) {
2323 thread_suspend_one(td2);
2325 if (sending || td != td2)
2326 td2->td_flags |= TDF_ASTPENDING;
2328 if (TD_IS_RUNNING(td2) && td2 != td)
2329 forward_signal(td2);
2337 ptracestop(struct thread *td, int sig)
2339 struct proc *p = td->td_proc;
2341 PROC_LOCK_ASSERT(p, MA_OWNED);
2342 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2343 &p->p_mtx.lock_object, "Stopping for traced signal");
2346 td->td_flags |= TDF_XSIG;
2350 while ((p->p_flag & P_TRACED) && (td->td_flags & TDF_XSIG)) {
2351 if (p->p_flag & P_SINGLE_EXIT) {
2353 td->td_flags &= ~TDF_XSIG;
2359 * Just make wait() to work, the last stopped thread
2364 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2365 sig_suspend_threads(td, p, 0);
2367 thread_suspend_switch(td);
2368 if (!(p->p_flag & P_TRACED)) {
2371 if (td->td_flags & TDF_DBSUSPEND) {
2372 if (p->p_flag & P_SINGLE_EXIT)
2378 return (td->td_xsig);
2382 * If the current process has received a signal (should be caught or cause
2383 * termination, should interrupt current syscall), return the signal number.
2384 * Stop signals with default action are processed immediately, then cleared;
2385 * they aren't returned. This is checked after each entry to the system for
2386 * a syscall or trap (though this can usually be done without calling issignal
2387 * by checking the pending signal masks in cursig.) The normal call
2390 * while (sig = cursig(curthread))
2399 sigset_t sigpending;
2400 int sig, prop, newsig;
2404 mtx_assert(&ps->ps_mtx, MA_OWNED);
2405 PROC_LOCK_ASSERT(p, MA_OWNED);
2407 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2409 sigpending = td->td_sigqueue.sq_signals;
2410 SIGSETNAND(sigpending, td->td_sigmask);
2412 if (p->p_flag & P_PPWAIT)
2413 SIG_STOPSIGMASK(sigpending);
2414 if (SIGISEMPTY(sigpending)) /* no signal to send */
2416 sig = sig_ffs(&sigpending);
2418 if (p->p_stops & S_SIG) {
2419 mtx_unlock(&ps->ps_mtx);
2420 stopevent(p, S_SIG, sig);
2421 mtx_lock(&ps->ps_mtx);
2425 * We should see pending but ignored signals
2426 * only if P_TRACED was on when they were posted.
2428 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2429 sigqueue_delete(&td->td_sigqueue, sig);
2432 if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
2434 * If traced, always stop.
2436 mtx_unlock(&ps->ps_mtx);
2437 newsig = ptracestop(td, sig);
2438 mtx_lock(&ps->ps_mtx);
2440 if (sig != newsig) {
2444 * XXX shrug off debugger, it causes siginfo to
2447 sigqueue_get(&td->td_sigqueue, sig, &ksi);
2450 * If parent wants us to take the signal,
2451 * then it will leave it in p->p_xstat;
2452 * otherwise we just look for signals again.
2459 * Put the new signal into td_sigqueue. If the
2460 * signal is being masked, look for other signals.
2462 SIGADDSET(td->td_sigqueue.sq_signals, sig);
2463 if (SIGISMEMBER(td->td_sigmask, sig))
2469 * If the traced bit got turned off, go back up
2470 * to the top to rescan signals. This ensures
2471 * that p_sig* and p_sigact are consistent.
2473 if ((p->p_flag & P_TRACED) == 0)
2477 prop = sigprop(sig);
2480 * Decide whether the signal should be returned.
2481 * Return the signal's number, or fall through
2482 * to clear it from the pending mask.
2484 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2486 case (intptr_t)SIG_DFL:
2488 * Don't take default actions on system processes.
2490 if (p->p_pid <= 1) {
2493 * Are you sure you want to ignore SIGSEGV
2496 printf("Process (pid %lu) got signal %d\n",
2497 (u_long)p->p_pid, sig);
2499 break; /* == ignore */
2502 * If there is a pending stop signal to process
2503 * with default action, stop here,
2504 * then clear the signal. However,
2505 * if process is member of an orphaned
2506 * process group, ignore tty stop signals.
2508 if (prop & SA_STOP) {
2509 if (p->p_flag & P_TRACED ||
2510 (p->p_pgrp->pg_jobc == 0 &&
2512 break; /* == ignore */
2513 mtx_unlock(&ps->ps_mtx);
2514 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2515 &p->p_mtx.lock_object, "Catching SIGSTOP");
2516 p->p_flag |= P_STOPPED_SIG;
2519 sig_suspend_threads(td, p, 0);
2520 thread_suspend_switch(td);
2522 mtx_lock(&ps->ps_mtx);
2524 } else if (prop & SA_IGNORE) {
2526 * Except for SIGCONT, shouldn't get here.
2527 * Default action is to ignore; drop it.
2529 break; /* == ignore */
2534 case (intptr_t)SIG_IGN:
2536 * Masking above should prevent us ever trying
2537 * to take action on an ignored signal other
2538 * than SIGCONT, unless process is traced.
2540 if ((prop & SA_CONT) == 0 &&
2541 (p->p_flag & P_TRACED) == 0)
2542 printf("issignal\n");
2543 break; /* == ignore */
2547 * This signal has an action, let
2548 * postsig() process it.
2552 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2558 thread_stopped(struct proc *p)
2562 PROC_LOCK_ASSERT(p, MA_OWNED);
2563 PROC_SLOCK_ASSERT(p, MA_OWNED);
2567 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2569 p->p_flag &= ~P_WAITED;
2570 PROC_LOCK(p->p_pptr);
2571 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2572 CLD_TRAPPED : CLD_STOPPED);
2573 PROC_UNLOCK(p->p_pptr);
2579 * Take the action for the specified signal
2580 * from the current set of pending signals.
2586 struct thread *td = curthread;
2587 register struct proc *p = td->td_proc;
2591 sigset_t returnmask;
2594 KASSERT(sig != 0, ("postsig"));
2596 PROC_LOCK_ASSERT(p, MA_OWNED);
2598 mtx_assert(&ps->ps_mtx, MA_OWNED);
2599 ksiginfo_init(&ksi);
2600 sigqueue_get(&td->td_sigqueue, sig, &ksi);
2601 ksi.ksi_signo = sig;
2602 if (ksi.ksi_code == SI_TIMER)
2603 itimer_accept(p, ksi.ksi_timerid, &ksi);
2604 action = ps->ps_sigact[_SIG_IDX(sig)];
2606 if (KTRPOINT(td, KTR_PSIG))
2607 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2608 &td->td_oldsigmask : &td->td_sigmask, 0);
2610 if (p->p_stops & S_SIG) {
2611 mtx_unlock(&ps->ps_mtx);
2612 stopevent(p, S_SIG, sig);
2613 mtx_lock(&ps->ps_mtx);
2616 if (action == SIG_DFL) {
2618 * Default action, where the default is to kill
2619 * the process. (Other cases were ignored above.)
2621 mtx_unlock(&ps->ps_mtx);
2626 * If we get here, the signal must be caught.
2628 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2629 ("postsig action"));
2631 * Set the new mask value and also defer further
2632 * occurrences of this signal.
2634 * Special case: user has done a sigsuspend. Here the
2635 * current mask is not of interest, but rather the
2636 * mask from before the sigsuspend is what we want
2637 * restored after the signal processing is completed.
2639 if (td->td_pflags & TDP_OLDMASK) {
2640 returnmask = td->td_oldsigmask;
2641 td->td_pflags &= ~TDP_OLDMASK;
2643 returnmask = td->td_sigmask;
2645 SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
2646 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2647 SIGADDSET(td->td_sigmask, sig);
2649 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2651 * See kern_sigaction() for origin of this code.
2653 SIGDELSET(ps->ps_sigcatch, sig);
2654 if (sig != SIGCONT &&
2655 sigprop(sig) & SA_IGNORE)
2656 SIGADDSET(ps->ps_sigignore, sig);
2657 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2659 td->td_ru.ru_nsignals++;
2660 if (p->p_sig != sig) {
2667 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2672 * Kill the current process for stated reason.
2680 PROC_LOCK_ASSERT(p, MA_OWNED);
2681 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)",
2682 p, p->p_pid, p->p_comm);
2683 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
2684 p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2685 psignal(p, SIGKILL);
2689 * Force the current process to exit with the specified signal, dumping core
2690 * if appropriate. We bypass the normal tests for masked and caught signals,
2691 * allowing unrecoverable failures to terminate the process without changing
2692 * signal state. Mark the accounting record with the signal termination.
2693 * If dumping core, save the signal number for the debugger. Calls exit and
2701 struct proc *p = td->td_proc;
2703 PROC_LOCK_ASSERT(p, MA_OWNED);
2704 p->p_acflag |= AXSIG;
2706 * We must be single-threading to generate a core dump. This
2707 * ensures that the registers in the core file are up-to-date.
2708 * Also, the ELF dump handler assumes that the thread list doesn't
2709 * change out from under it.
2711 * XXX If another thread attempts to single-thread before us
2712 * (e.g. via fork()), we won't get a dump at all.
2714 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2717 * Log signals which would cause core dumps
2718 * (Log as LOG_INFO to appease those who don't want
2720 * XXX : Todo, as well as euid, write out ruid too
2721 * Note that coredump() drops proc lock.
2723 if (coredump(td) == 0)
2725 if (kern_logsigexit)
2727 "pid %d (%s), uid %d: exited on signal %d%s\n",
2728 p->p_pid, p->p_comm,
2729 td->td_ucred ? td->td_ucred->cr_uid : -1,
2731 sig & WCOREFLAG ? " (core dumped)" : "");
2734 exit1(td, W_EXITCODE(0, sig));
2739 * Send queued SIGCHLD to parent when child process's state
2743 sigparent(struct proc *p, int reason, int status)
2745 PROC_LOCK_ASSERT(p, MA_OWNED);
2746 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2748 if (p->p_ksi != NULL) {
2749 p->p_ksi->ksi_signo = SIGCHLD;
2750 p->p_ksi->ksi_code = reason;
2751 p->p_ksi->ksi_status = status;
2752 p->p_ksi->ksi_pid = p->p_pid;
2753 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2754 if (KSI_ONQ(p->p_ksi))
2757 tdsignal(p->p_pptr, NULL, SIGCHLD, p->p_ksi);
2761 childproc_jobstate(struct proc *p, int reason, int status)
2765 PROC_LOCK_ASSERT(p, MA_OWNED);
2766 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2769 * Wake up parent sleeping in kern_wait(), also send
2770 * SIGCHLD to parent, but SIGCHLD does not guarantee
2771 * that parent will awake, because parent may masked
2774 p->p_pptr->p_flag |= P_STATCHILD;
2777 ps = p->p_pptr->p_sigacts;
2778 mtx_lock(&ps->ps_mtx);
2779 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2780 mtx_unlock(&ps->ps_mtx);
2781 sigparent(p, reason, status);
2783 mtx_unlock(&ps->ps_mtx);
2787 childproc_stopped(struct proc *p, int reason)
2789 childproc_jobstate(p, reason, p->p_xstat);
2793 childproc_continued(struct proc *p)
2795 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
2799 childproc_exited(struct proc *p)
2802 int status = p->p_xstat; /* convert to int */
2804 reason = CLD_EXITED;
2805 if (WCOREDUMP(status))
2806 reason = CLD_DUMPED;
2807 else if (WIFSIGNALED(status))
2808 reason = CLD_KILLED;
2810 * XXX avoid calling wakeup(p->p_pptr), the work is
2813 sigparent(p, reason, status);
2816 static char corefilename[MAXPATHLEN] = {"%N.core"};
2817 SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
2818 sizeof(corefilename), "process corefile name format string");
2821 * expand_name(name, uid, pid)
2822 * Expand the name described in corefilename, using name, uid, and pid.
2823 * corefilename is a printf-like string, with three format specifiers:
2824 * %N name of process ("name")
2825 * %P process id (pid)
2827 * For example, "%N.core" is the default; they can be disabled completely
2828 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
2829 * This is controlled by the sysctl variable kern.corefile (see above).
2832 expand_name(name, uid, pid)
2842 format = corefilename;
2843 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
2846 (void)sbuf_new(&sb, temp, MAXPATHLEN, SBUF_FIXEDLEN);
2847 for (i = 0; format[i]; i++) {
2848 switch (format[i]) {
2849 case '%': /* Format character */
2851 switch (format[i]) {
2853 sbuf_putc(&sb, '%');
2855 case 'N': /* process name */
2856 sbuf_printf(&sb, "%s", name);
2858 case 'P': /* process id */
2859 sbuf_printf(&sb, "%u", pid);
2861 case 'U': /* user id */
2862 sbuf_printf(&sb, "%u", uid);
2866 "Unknown format character %c in "
2867 "corename `%s'\n", format[i], format);
2871 sbuf_putc(&sb, format[i]);
2874 if (sbuf_overflowed(&sb)) {
2876 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
2877 "long\n", (long)pid, name, (u_long)uid);
2887 * Dump a process' core. The main routine does some
2888 * policy checking, and creates the name of the coredump;
2889 * then it passes on a vnode and a size limit to the process-specific
2890 * coredump routine if there is one; if there _is not_ one, it returns
2891 * ENOSYS; otherwise it returns the error from the process-specific routine.
2895 coredump(struct thread *td)
2897 struct proc *p = td->td_proc;
2898 register struct vnode *vp;
2899 register struct ucred *cred = td->td_ucred;
2901 struct nameidata nd;
2903 int error, error1, flags, locked;
2905 char *name; /* name of corefile */
2909 PROC_LOCK_ASSERT(p, MA_OWNED);
2910 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
2911 _STOPEVENT(p, S_CORE, 0);
2913 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid);
2917 audit_proc_coredump(td, NULL, EINVAL);
2921 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) {
2924 audit_proc_coredump(td, name, EFAULT);
2931 * Note that the bulk of limit checking is done after
2932 * the corefile is created. The exception is if the limit
2933 * for corefiles is 0, in which case we don't bother
2934 * creating the corefile at all. This layout means that
2935 * a corefile is truncated instead of not being created,
2936 * if it is larger than the limit.
2938 limit = (off_t)lim_cur(p, RLIMIT_CORE);
2942 audit_proc_coredump(td, name, EFBIG);
2949 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, name, td);
2950 flags = O_CREAT | FWRITE | O_NOFOLLOW;
2951 error = vn_open(&nd, &flags, S_IRUSR | S_IWUSR, NULL);
2954 audit_proc_coredump(td, name, error);
2959 vfslocked = NDHASGIANT(&nd);
2960 NDFREE(&nd, NDF_ONLY_PNBUF);
2963 /* Don't dump to non-regular files or files with links. */
2964 if (vp->v_type != VREG ||
2965 VOP_GETATTR(vp, &vattr, cred, td) || vattr.va_nlink != 1) {
2972 lf.l_whence = SEEK_SET;
2975 lf.l_type = F_WRLCK;
2976 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
2978 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
2979 lf.l_type = F_UNLCK;
2981 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
2982 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
2984 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
2986 VFS_UNLOCK_GIANT(vfslocked);
2992 if (set_core_nodump_flag)
2993 vattr.va_flags = UF_NODUMP;
2994 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2995 VOP_LEASE(vp, td, cred, LEASE_WRITE);
2996 VOP_SETATTR(vp, &vattr, cred, td);
2998 vn_finished_write(mp);
3000 p->p_acflag |= ACORE;
3003 error = p->p_sysent->sv_coredump ?
3004 p->p_sysent->sv_coredump(td, vp, limit) :
3008 lf.l_type = F_UNLCK;
3009 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3012 error1 = vn_close(vp, FWRITE, cred, td);
3017 audit_proc_coredump(td, name, error);
3020 VFS_UNLOCK_GIANT(vfslocked);
3025 * Nonexistent system call-- signal process (may want to handle it). Flag
3026 * error in case process won't see signal immediately (blocked or ignored).
3028 #ifndef _SYS_SYSPROTO_H_
3037 struct nosys_args *args;
3039 struct proc *p = td->td_proc;
3048 * Send a SIGIO or SIGURG signal to a process or process group using stored
3049 * credentials rather than those of the current process.
3052 pgsigio(sigiop, sig, checkctty)
3053 struct sigio **sigiop;
3056 struct sigio *sigio;
3060 if (sigio == NULL) {
3064 if (sigio->sio_pgid > 0) {
3065 PROC_LOCK(sigio->sio_proc);
3066 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3067 psignal(sigio->sio_proc, sig);
3068 PROC_UNLOCK(sigio->sio_proc);
3069 } else if (sigio->sio_pgid < 0) {
3072 PGRP_LOCK(sigio->sio_pgrp);
3073 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3075 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3076 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3080 PGRP_UNLOCK(sigio->sio_pgrp);
3086 filt_sigattach(struct knote *kn)
3088 struct proc *p = curproc;
3090 kn->kn_ptr.p_proc = p;
3091 kn->kn_flags |= EV_CLEAR; /* automatically set */
3093 knlist_add(&p->p_klist, kn, 0);
3099 filt_sigdetach(struct knote *kn)
3101 struct proc *p = kn->kn_ptr.p_proc;
3103 knlist_remove(&p->p_klist, kn, 0);
3107 * signal knotes are shared with proc knotes, so we apply a mask to
3108 * the hint in order to differentiate them from process hints. This
3109 * could be avoided by using a signal-specific knote list, but probably
3110 * isn't worth the trouble.
3113 filt_signal(struct knote *kn, long hint)
3116 if (hint & NOTE_SIGNAL) {
3117 hint &= ~NOTE_SIGNAL;
3119 if (kn->kn_id == hint)
3122 return (kn->kn_data != 0);
3130 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3132 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3137 sigacts_free(struct sigacts *ps)
3140 mtx_lock(&ps->ps_mtx);
3142 if (ps->ps_refcnt == 0) {
3143 mtx_destroy(&ps->ps_mtx);
3144 free(ps, M_SUBPROC);
3146 mtx_unlock(&ps->ps_mtx);
3150 sigacts_hold(struct sigacts *ps)
3152 mtx_lock(&ps->ps_mtx);
3154 mtx_unlock(&ps->ps_mtx);
3159 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3162 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3163 mtx_lock(&src->ps_mtx);
3164 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3165 mtx_unlock(&src->ps_mtx);
3169 sigacts_shared(struct sigacts *ps)
3173 mtx_lock(&ps->ps_mtx);
3174 shared = ps->ps_refcnt > 1;
3175 mtx_unlock(&ps->ps_mtx);