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
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
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11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
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18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
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25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * @(#)kern_sig.c 8.7 (Berkeley) 4/18/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
42 #include "opt_ktrace.h"
44 #include <sys/param.h>
45 #include <sys/ctype.h>
46 #include <sys/systm.h>
47 #include <sys/signalvar.h>
48 #include <sys/vnode.h>
51 #include <sys/capsicum.h>
52 #include <sys/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/refcount.h>
63 #include <sys/namei.h>
65 #include <sys/procdesc.h>
66 #include <sys/posix4.h>
67 #include <sys/pioctl.h>
68 #include <sys/racct.h>
69 #include <sys/resourcevar.h>
72 #include <sys/sleepqueue.h>
76 #include <sys/syscallsubr.h>
77 #include <sys/sysctl.h>
78 #include <sys/sysent.h>
79 #include <sys/syslog.h>
80 #include <sys/sysproto.h>
81 #include <sys/timers.h>
82 #include <sys/unistd.h>
85 #include <vm/vm_extern.h>
90 #include <machine/cpu.h>
92 #include <security/audit/audit.h>
94 #define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE3(proc, , , signal__send,
98 "struct thread *", "struct proc *", "int");
99 SDT_PROBE_DEFINE2(proc, , , signal__clear,
100 "int", "ksiginfo_t *");
101 SDT_PROBE_DEFINE3(proc, , , signal__discard,
102 "struct thread *", "struct proc *", "int");
104 static int coredump(struct thread *);
105 static int killpg1(struct thread *td, int sig, int pgid, int all,
107 static int issignal(struct thread *td);
108 static int sigprop(int sig);
109 static void tdsigwakeup(struct thread *, int, sig_t, int);
110 static int sig_suspend_threads(struct thread *, struct proc *, int);
111 static int filt_sigattach(struct knote *kn);
112 static void filt_sigdetach(struct knote *kn);
113 static int filt_signal(struct knote *kn, long hint);
114 static struct thread *sigtd(struct proc *p, int sig, int prop);
115 static void sigqueue_start(void);
117 static uma_zone_t ksiginfo_zone = NULL;
118 struct filterops sig_filtops = {
120 .f_attach = filt_sigattach,
121 .f_detach = filt_sigdetach,
122 .f_event = filt_signal,
125 static int kern_logsigexit = 1;
126 SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
128 "Log processes quitting on abnormal signals to syslog(3)");
130 static int kern_forcesigexit = 1;
131 SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
132 &kern_forcesigexit, 0, "Force trap signal to be handled");
134 static SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0,
135 "POSIX real time signal");
137 static int max_pending_per_proc = 128;
138 SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
139 &max_pending_per_proc, 0, "Max pending signals per proc");
141 static int preallocate_siginfo = 1024;
142 SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RDTUN,
143 &preallocate_siginfo, 0, "Preallocated signal memory size");
145 static int signal_overflow = 0;
146 SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
147 &signal_overflow, 0, "Number of signals overflew");
149 static int signal_alloc_fail = 0;
150 SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
151 &signal_alloc_fail, 0, "signals failed to be allocated");
153 SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
156 * Policy -- Can ucred cr1 send SIGIO to process cr2?
157 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
158 * in the right situations.
160 #define CANSIGIO(cr1, cr2) \
161 ((cr1)->cr_uid == 0 || \
162 (cr1)->cr_ruid == (cr2)->cr_ruid || \
163 (cr1)->cr_uid == (cr2)->cr_ruid || \
164 (cr1)->cr_ruid == (cr2)->cr_uid || \
165 (cr1)->cr_uid == (cr2)->cr_uid)
167 static int sugid_coredump;
168 SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RWTUN,
169 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
171 static int capmode_coredump;
172 SYSCTL_INT(_kern, OID_AUTO, capmode_coredump, CTLFLAG_RWTUN,
173 &capmode_coredump, 0, "Allow processes in capability mode to dump core");
175 static int do_coredump = 1;
176 SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
177 &do_coredump, 0, "Enable/Disable coredumps");
179 static int set_core_nodump_flag = 0;
180 SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
181 0, "Enable setting the NODUMP flag on coredump files");
183 static int coredump_devctl = 0;
184 SYSCTL_INT(_kern, OID_AUTO, coredump_devctl, CTLFLAG_RW, &coredump_devctl,
185 0, "Generate a devctl notification when processes coredump");
188 * Signal properties and actions.
189 * The array below categorizes the signals and their default actions
190 * according to the following properties:
192 #define SIGPROP_KILL 0x01 /* terminates process by default */
193 #define SIGPROP_CORE 0x02 /* ditto and coredumps */
194 #define SIGPROP_STOP 0x04 /* suspend process */
195 #define SIGPROP_TTYSTOP 0x08 /* ditto, from tty */
196 #define SIGPROP_IGNORE 0x10 /* ignore by default */
197 #define SIGPROP_CONT 0x20 /* continue if suspended */
198 #define SIGPROP_CANTMASK 0x40 /* non-maskable, catchable */
200 static int sigproptbl[NSIG] = {
201 [SIGHUP] = SIGPROP_KILL,
202 [SIGINT] = SIGPROP_KILL,
203 [SIGQUIT] = SIGPROP_KILL | SIGPROP_CORE,
204 [SIGILL] = SIGPROP_KILL | SIGPROP_CORE,
205 [SIGTRAP] = SIGPROP_KILL | SIGPROP_CORE,
206 [SIGABRT] = SIGPROP_KILL | SIGPROP_CORE,
207 [SIGEMT] = SIGPROP_KILL | SIGPROP_CORE,
208 [SIGFPE] = SIGPROP_KILL | SIGPROP_CORE,
209 [SIGKILL] = SIGPROP_KILL,
210 [SIGBUS] = SIGPROP_KILL | SIGPROP_CORE,
211 [SIGSEGV] = SIGPROP_KILL | SIGPROP_CORE,
212 [SIGSYS] = SIGPROP_KILL | SIGPROP_CORE,
213 [SIGPIPE] = SIGPROP_KILL,
214 [SIGALRM] = SIGPROP_KILL,
215 [SIGTERM] = SIGPROP_KILL,
216 [SIGURG] = SIGPROP_IGNORE,
217 [SIGSTOP] = SIGPROP_STOP,
218 [SIGTSTP] = SIGPROP_STOP | SIGPROP_TTYSTOP,
219 [SIGCONT] = SIGPROP_IGNORE | SIGPROP_CONT,
220 [SIGCHLD] = SIGPROP_IGNORE,
221 [SIGTTIN] = SIGPROP_STOP | SIGPROP_TTYSTOP,
222 [SIGTTOU] = SIGPROP_STOP | SIGPROP_TTYSTOP,
223 [SIGIO] = SIGPROP_IGNORE,
224 [SIGXCPU] = SIGPROP_KILL,
225 [SIGXFSZ] = SIGPROP_KILL,
226 [SIGVTALRM] = SIGPROP_KILL,
227 [SIGPROF] = SIGPROP_KILL,
228 [SIGWINCH] = SIGPROP_IGNORE,
229 [SIGINFO] = SIGPROP_IGNORE,
230 [SIGUSR1] = SIGPROP_KILL,
231 [SIGUSR2] = SIGPROP_KILL,
234 static void reschedule_signals(struct proc *p, sigset_t block, int flags);
239 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
240 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
241 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
242 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
243 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
244 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
248 ksiginfo_alloc(int wait)
255 if (ksiginfo_zone != NULL)
256 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
261 ksiginfo_free(ksiginfo_t *ksi)
263 uma_zfree(ksiginfo_zone, ksi);
267 ksiginfo_tryfree(ksiginfo_t *ksi)
269 if (!(ksi->ksi_flags & KSI_EXT)) {
270 uma_zfree(ksiginfo_zone, ksi);
277 sigqueue_init(sigqueue_t *list, struct proc *p)
279 SIGEMPTYSET(list->sq_signals);
280 SIGEMPTYSET(list->sq_kill);
281 SIGEMPTYSET(list->sq_ptrace);
282 TAILQ_INIT(&list->sq_list);
284 list->sq_flags = SQ_INIT;
288 * Get a signal's ksiginfo.
290 * 0 - signal not found
291 * others - signal number
294 sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
296 struct proc *p = sq->sq_proc;
297 struct ksiginfo *ksi, *next;
300 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
302 if (!SIGISMEMBER(sq->sq_signals, signo))
305 if (SIGISMEMBER(sq->sq_ptrace, signo)) {
307 SIGDELSET(sq->sq_ptrace, signo);
308 si->ksi_flags |= KSI_PTRACE;
310 if (SIGISMEMBER(sq->sq_kill, signo)) {
313 SIGDELSET(sq->sq_kill, signo);
316 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
317 if (ksi->ksi_signo == signo) {
319 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
320 ksi->ksi_sigq = NULL;
321 ksiginfo_copy(ksi, si);
322 if (ksiginfo_tryfree(ksi) && p != NULL)
331 SIGDELSET(sq->sq_signals, signo);
332 si->ksi_signo = signo;
337 sigqueue_take(ksiginfo_t *ksi)
343 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
347 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
348 ksi->ksi_sigq = NULL;
349 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
352 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
353 kp = TAILQ_NEXT(kp, ksi_link)) {
354 if (kp->ksi_signo == ksi->ksi_signo)
357 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo) &&
358 !SIGISMEMBER(sq->sq_ptrace, ksi->ksi_signo))
359 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
363 sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
365 struct proc *p = sq->sq_proc;
366 struct ksiginfo *ksi;
369 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
372 * SIGKILL/SIGSTOP cannot be caught or masked, so take the fast path
375 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
376 SIGADDSET(sq->sq_kill, signo);
380 /* directly insert the ksi, don't copy it */
381 if (si->ksi_flags & KSI_INS) {
382 if (si->ksi_flags & KSI_HEAD)
383 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
385 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
390 if (__predict_false(ksiginfo_zone == NULL)) {
391 SIGADDSET(sq->sq_kill, signo);
395 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
398 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
404 ksiginfo_copy(si, ksi);
405 ksi->ksi_signo = signo;
406 if (si->ksi_flags & KSI_HEAD)
407 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
409 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
414 if ((si->ksi_flags & KSI_PTRACE) != 0) {
415 SIGADDSET(sq->sq_ptrace, signo);
418 } else if ((si->ksi_flags & KSI_TRAP) != 0 ||
419 (si->ksi_flags & KSI_SIGQ) == 0) {
420 SIGADDSET(sq->sq_kill, signo);
428 SIGADDSET(sq->sq_signals, signo);
433 sigqueue_flush(sigqueue_t *sq)
435 struct proc *p = sq->sq_proc;
438 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
441 PROC_LOCK_ASSERT(p, MA_OWNED);
443 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
444 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
445 ksi->ksi_sigq = NULL;
446 if (ksiginfo_tryfree(ksi) && p != NULL)
450 SIGEMPTYSET(sq->sq_signals);
451 SIGEMPTYSET(sq->sq_kill);
452 SIGEMPTYSET(sq->sq_ptrace);
456 sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, const sigset_t *set)
459 struct proc *p1, *p2;
460 ksiginfo_t *ksi, *next;
462 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
463 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
466 /* Move siginfo to target list */
467 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
468 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
469 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
472 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
479 /* Move pending bits to target list */
481 SIGSETAND(tmp, *set);
482 SIGSETOR(dst->sq_kill, tmp);
483 SIGSETNAND(src->sq_kill, tmp);
485 tmp = src->sq_ptrace;
486 SIGSETAND(tmp, *set);
487 SIGSETOR(dst->sq_ptrace, tmp);
488 SIGSETNAND(src->sq_ptrace, tmp);
490 tmp = src->sq_signals;
491 SIGSETAND(tmp, *set);
492 SIGSETOR(dst->sq_signals, tmp);
493 SIGSETNAND(src->sq_signals, tmp);
498 sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
503 SIGADDSET(set, signo);
504 sigqueue_move_set(src, dst, &set);
509 sigqueue_delete_set(sigqueue_t *sq, const sigset_t *set)
511 struct proc *p = sq->sq_proc;
512 ksiginfo_t *ksi, *next;
514 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
516 /* Remove siginfo queue */
517 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
518 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
519 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
520 ksi->ksi_sigq = NULL;
521 if (ksiginfo_tryfree(ksi) && p != NULL)
525 SIGSETNAND(sq->sq_kill, *set);
526 SIGSETNAND(sq->sq_ptrace, *set);
527 SIGSETNAND(sq->sq_signals, *set);
531 sigqueue_delete(sigqueue_t *sq, int signo)
536 SIGADDSET(set, signo);
537 sigqueue_delete_set(sq, &set);
540 /* Remove a set of signals for a process */
542 sigqueue_delete_set_proc(struct proc *p, const sigset_t *set)
547 PROC_LOCK_ASSERT(p, MA_OWNED);
549 sigqueue_init(&worklist, NULL);
550 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
552 FOREACH_THREAD_IN_PROC(p, td0)
553 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
555 sigqueue_flush(&worklist);
559 sigqueue_delete_proc(struct proc *p, int signo)
564 SIGADDSET(set, signo);
565 sigqueue_delete_set_proc(p, &set);
569 sigqueue_delete_stopmask_proc(struct proc *p)
574 SIGADDSET(set, SIGSTOP);
575 SIGADDSET(set, SIGTSTP);
576 SIGADDSET(set, SIGTTIN);
577 SIGADDSET(set, SIGTTOU);
578 sigqueue_delete_set_proc(p, &set);
582 * Determine signal that should be delivered to thread td, the current
583 * thread, 0 if none. If there is a pending stop signal with default
584 * action, the process stops in issignal().
587 cursig(struct thread *td)
589 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
590 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
591 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
592 return (SIGPENDING(td) ? issignal(td) : 0);
596 * Arrange for ast() to handle unmasked pending signals on return to user
597 * mode. This must be called whenever a signal is added to td_sigqueue or
598 * unmasked in td_sigmask.
601 signotify(struct thread *td)
607 PROC_LOCK_ASSERT(p, MA_OWNED);
609 if (SIGPENDING(td)) {
611 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
617 sigonstack(size_t sp)
619 struct thread *td = curthread;
621 return ((td->td_pflags & TDP_ALTSTACK) ?
622 #if defined(COMPAT_43)
623 ((td->td_sigstk.ss_size == 0) ?
624 (td->td_sigstk.ss_flags & SS_ONSTACK) :
625 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
627 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
636 if (sig > 0 && sig < nitems(sigproptbl))
637 return (sigproptbl[sig]);
642 sig_ffs(sigset_t *set)
646 for (i = 0; i < _SIG_WORDS; i++)
648 return (ffs(set->__bits[i]) + (i * 32));
653 sigact_flag_test(const struct sigaction *act, int flag)
657 * SA_SIGINFO is reset when signal disposition is set to
658 * ignore or default. Other flags are kept according to user
661 return ((act->sa_flags & flag) != 0 && (flag != SA_SIGINFO ||
662 ((__sighandler_t *)act->sa_sigaction != SIG_IGN &&
663 (__sighandler_t *)act->sa_sigaction != SIG_DFL)));
673 kern_sigaction(struct thread *td, int sig, const struct sigaction *act,
674 struct sigaction *oact, int flags)
677 struct proc *p = td->td_proc;
679 if (!_SIG_VALID(sig))
681 if (act != NULL && act->sa_handler != SIG_DFL &&
682 act->sa_handler != SIG_IGN && (act->sa_flags & ~(SA_ONSTACK |
683 SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER |
684 SA_NOCLDWAIT | SA_SIGINFO)) != 0)
689 mtx_lock(&ps->ps_mtx);
691 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
693 if (SIGISMEMBER(ps->ps_sigonstack, sig))
694 oact->sa_flags |= SA_ONSTACK;
695 if (!SIGISMEMBER(ps->ps_sigintr, sig))
696 oact->sa_flags |= SA_RESTART;
697 if (SIGISMEMBER(ps->ps_sigreset, sig))
698 oact->sa_flags |= SA_RESETHAND;
699 if (SIGISMEMBER(ps->ps_signodefer, sig))
700 oact->sa_flags |= SA_NODEFER;
701 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
702 oact->sa_flags |= SA_SIGINFO;
704 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
706 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
707 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
708 oact->sa_flags |= SA_NOCLDSTOP;
709 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
710 oact->sa_flags |= SA_NOCLDWAIT;
713 if ((sig == SIGKILL || sig == SIGSTOP) &&
714 act->sa_handler != SIG_DFL) {
715 mtx_unlock(&ps->ps_mtx);
721 * Change setting atomically.
724 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
725 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
726 if (sigact_flag_test(act, SA_SIGINFO)) {
727 ps->ps_sigact[_SIG_IDX(sig)] =
728 (__sighandler_t *)act->sa_sigaction;
729 SIGADDSET(ps->ps_siginfo, sig);
731 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
732 SIGDELSET(ps->ps_siginfo, sig);
734 if (!sigact_flag_test(act, SA_RESTART))
735 SIGADDSET(ps->ps_sigintr, sig);
737 SIGDELSET(ps->ps_sigintr, sig);
738 if (sigact_flag_test(act, SA_ONSTACK))
739 SIGADDSET(ps->ps_sigonstack, sig);
741 SIGDELSET(ps->ps_sigonstack, sig);
742 if (sigact_flag_test(act, SA_RESETHAND))
743 SIGADDSET(ps->ps_sigreset, sig);
745 SIGDELSET(ps->ps_sigreset, sig);
746 if (sigact_flag_test(act, SA_NODEFER))
747 SIGADDSET(ps->ps_signodefer, sig);
749 SIGDELSET(ps->ps_signodefer, sig);
750 if (sig == SIGCHLD) {
751 if (act->sa_flags & SA_NOCLDSTOP)
752 ps->ps_flag |= PS_NOCLDSTOP;
754 ps->ps_flag &= ~PS_NOCLDSTOP;
755 if (act->sa_flags & SA_NOCLDWAIT) {
757 * Paranoia: since SA_NOCLDWAIT is implemented
758 * by reparenting the dying child to PID 1 (and
759 * trust it to reap the zombie), PID 1 itself
760 * is forbidden to set SA_NOCLDWAIT.
763 ps->ps_flag &= ~PS_NOCLDWAIT;
765 ps->ps_flag |= PS_NOCLDWAIT;
767 ps->ps_flag &= ~PS_NOCLDWAIT;
768 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
769 ps->ps_flag |= PS_CLDSIGIGN;
771 ps->ps_flag &= ~PS_CLDSIGIGN;
774 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
775 * and for signals set to SIG_DFL where the default is to
776 * ignore. However, don't put SIGCONT in ps_sigignore, as we
777 * have to restart the process.
779 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
780 (sigprop(sig) & SIGPROP_IGNORE &&
781 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
782 /* never to be seen again */
783 sigqueue_delete_proc(p, sig);
785 /* easier in psignal */
786 SIGADDSET(ps->ps_sigignore, sig);
787 SIGDELSET(ps->ps_sigcatch, sig);
789 SIGDELSET(ps->ps_sigignore, sig);
790 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
791 SIGDELSET(ps->ps_sigcatch, sig);
793 SIGADDSET(ps->ps_sigcatch, sig);
795 #ifdef COMPAT_FREEBSD4
796 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
797 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
798 (flags & KSA_FREEBSD4) == 0)
799 SIGDELSET(ps->ps_freebsd4, sig);
801 SIGADDSET(ps->ps_freebsd4, sig);
804 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
805 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
806 (flags & KSA_OSIGSET) == 0)
807 SIGDELSET(ps->ps_osigset, sig);
809 SIGADDSET(ps->ps_osigset, sig);
812 mtx_unlock(&ps->ps_mtx);
817 #ifndef _SYS_SYSPROTO_H_
818 struct sigaction_args {
820 struct sigaction *act;
821 struct sigaction *oact;
825 sys_sigaction(struct thread *td, struct sigaction_args *uap)
827 struct sigaction act, oact;
828 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, 0);
840 error = copyout(oactp, uap->oact, sizeof(oact));
844 #ifdef COMPAT_FREEBSD4
845 #ifndef _SYS_SYSPROTO_H_
846 struct freebsd4_sigaction_args {
848 struct sigaction *act;
849 struct sigaction *oact;
853 freebsd4_sigaction(struct thread *td, struct freebsd4_sigaction_args *uap)
855 struct sigaction act, oact;
856 struct sigaction *actp, *oactp;
860 actp = (uap->act != NULL) ? &act : NULL;
861 oactp = (uap->oact != NULL) ? &oact : NULL;
863 error = copyin(uap->act, actp, sizeof(act));
867 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
869 error = copyout(oactp, uap->oact, sizeof(oact));
872 #endif /* COMAPT_FREEBSD4 */
874 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
875 #ifndef _SYS_SYSPROTO_H_
876 struct osigaction_args {
878 struct osigaction *nsa;
879 struct osigaction *osa;
883 osigaction(struct thread *td, struct osigaction_args *uap)
885 struct osigaction sa;
886 struct sigaction nsa, osa;
887 struct sigaction *nsap, *osap;
890 if (uap->signum <= 0 || uap->signum >= ONSIG)
893 nsap = (uap->nsa != NULL) ? &nsa : NULL;
894 osap = (uap->osa != NULL) ? &osa : NULL;
897 error = copyin(uap->nsa, &sa, sizeof(sa));
900 nsap->sa_handler = sa.sa_handler;
901 nsap->sa_flags = sa.sa_flags;
902 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
904 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
905 if (osap && !error) {
906 sa.sa_handler = osap->sa_handler;
907 sa.sa_flags = osap->sa_flags;
908 SIG2OSIG(osap->sa_mask, sa.sa_mask);
909 error = copyout(&sa, uap->osa, sizeof(sa));
914 #if !defined(__i386__)
915 /* Avoid replicating the same stub everywhere */
917 osigreturn(struct thread *td, struct osigreturn_args *uap)
920 return (nosys(td, (struct nosys_args *)uap));
923 #endif /* COMPAT_43 */
926 * Initialize signal state for process 0;
927 * set to ignore signals that are ignored by default.
930 siginit(struct proc *p)
937 mtx_lock(&ps->ps_mtx);
938 for (i = 1; i <= NSIG; i++) {
939 if (sigprop(i) & SIGPROP_IGNORE && i != SIGCONT) {
940 SIGADDSET(ps->ps_sigignore, i);
943 mtx_unlock(&ps->ps_mtx);
948 * Reset specified signal to the default disposition.
951 sigdflt(struct sigacts *ps, int sig)
954 mtx_assert(&ps->ps_mtx, MA_OWNED);
955 SIGDELSET(ps->ps_sigcatch, sig);
956 if ((sigprop(sig) & SIGPROP_IGNORE) != 0 && sig != SIGCONT)
957 SIGADDSET(ps->ps_sigignore, sig);
958 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
959 SIGDELSET(ps->ps_siginfo, sig);
963 * Reset signals for an exec of the specified process.
966 execsigs(struct proc *p)
974 * Reset caught signals. Held signals remain held
975 * through td_sigmask (unless they were caught,
976 * and are now ignored by default).
978 PROC_LOCK_ASSERT(p, MA_OWNED);
979 td = FIRST_THREAD_IN_PROC(p);
981 mtx_lock(&ps->ps_mtx);
982 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
983 sig = sig_ffs(&ps->ps_sigcatch);
985 if ((sigprop(sig) & SIGPROP_IGNORE) != 0)
986 sigqueue_delete_proc(p, sig);
990 * As CloudABI processes cannot modify signal handlers, fully
991 * reset all signals to their default behavior. Do ignore
992 * SIGPIPE, as it would otherwise be impossible to recover from
993 * writes to broken pipes and sockets.
995 if (SV_PROC_ABI(p) == SV_ABI_CLOUDABI) {
996 osigignore = ps->ps_sigignore;
997 while (SIGNOTEMPTY(osigignore)) {
998 sig = sig_ffs(&osigignore);
999 SIGDELSET(osigignore, sig);
1003 SIGADDSET(ps->ps_sigignore, SIGPIPE);
1007 * Reset stack state to the user stack.
1008 * Clear set of signals caught on the signal stack.
1010 td->td_sigstk.ss_flags = SS_DISABLE;
1011 td->td_sigstk.ss_size = 0;
1012 td->td_sigstk.ss_sp = 0;
1013 td->td_pflags &= ~TDP_ALTSTACK;
1015 * Reset no zombies if child dies flag as Solaris does.
1017 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
1018 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
1019 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
1020 mtx_unlock(&ps->ps_mtx);
1024 * kern_sigprocmask()
1026 * Manipulate signal mask.
1029 kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
1032 sigset_t new_block, oset1;
1037 if ((flags & SIGPROCMASK_PROC_LOCKED) != 0)
1038 PROC_LOCK_ASSERT(p, MA_OWNED);
1041 mtx_assert(&p->p_sigacts->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0
1042 ? MA_OWNED : MA_NOTOWNED);
1044 *oset = td->td_sigmask;
1051 oset1 = td->td_sigmask;
1052 SIGSETOR(td->td_sigmask, *set);
1053 new_block = td->td_sigmask;
1054 SIGSETNAND(new_block, oset1);
1057 SIGSETNAND(td->td_sigmask, *set);
1062 oset1 = td->td_sigmask;
1063 if (flags & SIGPROCMASK_OLD)
1064 SIGSETLO(td->td_sigmask, *set);
1066 td->td_sigmask = *set;
1067 new_block = td->td_sigmask;
1068 SIGSETNAND(new_block, oset1);
1077 * The new_block set contains signals that were not previously
1078 * blocked, but are blocked now.
1080 * In case we block any signal that was not previously blocked
1081 * for td, and process has the signal pending, try to schedule
1082 * signal delivery to some thread that does not block the
1083 * signal, possibly waking it up.
1085 if (p->p_numthreads != 1)
1086 reschedule_signals(p, new_block, flags);
1090 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1095 #ifndef _SYS_SYSPROTO_H_
1096 struct sigprocmask_args {
1098 const sigset_t *set;
1103 sys_sigprocmask(struct thread *td, struct sigprocmask_args *uap)
1106 sigset_t *setp, *osetp;
1109 setp = (uap->set != NULL) ? &set : NULL;
1110 osetp = (uap->oset != NULL) ? &oset : NULL;
1112 error = copyin(uap->set, setp, sizeof(set));
1116 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1117 if (osetp && !error) {
1118 error = copyout(osetp, uap->oset, sizeof(oset));
1123 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1124 #ifndef _SYS_SYSPROTO_H_
1125 struct osigprocmask_args {
1131 osigprocmask(struct thread *td, struct osigprocmask_args *uap)
1136 OSIG2SIG(uap->mask, set);
1137 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1138 SIG2OSIG(oset, td->td_retval[0]);
1141 #endif /* COMPAT_43 */
1144 sys_sigwait(struct thread *td, struct sigwait_args *uap)
1150 error = copyin(uap->set, &set, sizeof(set));
1152 td->td_retval[0] = error;
1156 error = kern_sigtimedwait(td, set, &ksi, NULL);
1158 if (error == EINTR && td->td_proc->p_osrel < P_OSREL_SIGWAIT)
1160 if (error == ERESTART)
1162 td->td_retval[0] = error;
1166 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1167 td->td_retval[0] = error;
1172 sys_sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1175 struct timespec *timeout;
1181 error = copyin(uap->timeout, &ts, sizeof(ts));
1189 error = copyin(uap->set, &set, sizeof(set));
1193 error = kern_sigtimedwait(td, set, &ksi, timeout);
1198 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1201 td->td_retval[0] = ksi.ksi_signo;
1206 sys_sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1212 error = copyin(uap->set, &set, sizeof(set));
1216 error = kern_sigtimedwait(td, set, &ksi, NULL);
1221 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1224 td->td_retval[0] = ksi.ksi_signo;
1229 kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1230 struct timespec *timeout)
1233 sigset_t saved_mask, new_block;
1235 int error, sig, timo, timevalid = 0;
1236 struct timespec rts, ets, ts;
1244 if (timeout != NULL) {
1245 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1247 getnanouptime(&rts);
1249 timespecadd(&ets, timeout);
1253 /* Some signals can not be waited for. */
1254 SIG_CANTMASK(waitset);
1257 saved_mask = td->td_sigmask;
1258 SIGSETNAND(td->td_sigmask, waitset);
1260 mtx_lock(&ps->ps_mtx);
1262 mtx_unlock(&ps->ps_mtx);
1263 KASSERT(sig >= 0, ("sig %d", sig));
1264 if (sig != 0 && SIGISMEMBER(waitset, sig)) {
1265 if (sigqueue_get(&td->td_sigqueue, sig, ksi) != 0 ||
1266 sigqueue_get(&p->p_sigqueue, sig, ksi) != 0) {
1276 * POSIX says this must be checked after looking for pending
1279 if (timeout != NULL) {
1284 getnanouptime(&rts);
1285 if (timespeccmp(&rts, &ets, >=)) {
1290 timespecsub(&ts, &rts);
1291 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1297 error = msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", timo);
1299 if (timeout != NULL) {
1300 if (error == ERESTART) {
1301 /* Timeout can not be restarted. */
1303 } else if (error == EAGAIN) {
1304 /* We will calculate timeout by ourself. */
1310 new_block = saved_mask;
1311 SIGSETNAND(new_block, td->td_sigmask);
1312 td->td_sigmask = saved_mask;
1314 * Fewer signals can be delivered to us, reschedule signal
1317 if (p->p_numthreads != 1)
1318 reschedule_signals(p, new_block, 0);
1321 SDT_PROBE2(proc, , , signal__clear, sig, ksi);
1323 if (ksi->ksi_code == SI_TIMER)
1324 itimer_accept(p, ksi->ksi_timerid, ksi);
1327 if (KTRPOINT(td, KTR_PSIG)) {
1330 mtx_lock(&ps->ps_mtx);
1331 action = ps->ps_sigact[_SIG_IDX(sig)];
1332 mtx_unlock(&ps->ps_mtx);
1333 ktrpsig(sig, action, &td->td_sigmask, ksi->ksi_code);
1343 #ifndef _SYS_SYSPROTO_H_
1344 struct sigpending_args {
1349 sys_sigpending(struct thread *td, struct sigpending_args *uap)
1351 struct proc *p = td->td_proc;
1355 pending = p->p_sigqueue.sq_signals;
1356 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1358 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1361 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1362 #ifndef _SYS_SYSPROTO_H_
1363 struct osigpending_args {
1368 osigpending(struct thread *td, struct osigpending_args *uap)
1370 struct proc *p = td->td_proc;
1374 pending = p->p_sigqueue.sq_signals;
1375 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1377 SIG2OSIG(pending, td->td_retval[0]);
1380 #endif /* COMPAT_43 */
1382 #if defined(COMPAT_43)
1384 * Generalized interface signal handler, 4.3-compatible.
1386 #ifndef _SYS_SYSPROTO_H_
1387 struct osigvec_args {
1395 osigvec(struct thread *td, struct osigvec_args *uap)
1398 struct sigaction nsa, osa;
1399 struct sigaction *nsap, *osap;
1402 if (uap->signum <= 0 || uap->signum >= ONSIG)
1404 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1405 osap = (uap->osv != NULL) ? &osa : NULL;
1407 error = copyin(uap->nsv, &vec, sizeof(vec));
1410 nsap->sa_handler = vec.sv_handler;
1411 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1412 nsap->sa_flags = vec.sv_flags;
1413 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1415 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1416 if (osap && !error) {
1417 vec.sv_handler = osap->sa_handler;
1418 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1419 vec.sv_flags = osap->sa_flags;
1420 vec.sv_flags &= ~SA_NOCLDWAIT;
1421 vec.sv_flags ^= SA_RESTART;
1422 error = copyout(&vec, uap->osv, sizeof(vec));
1427 #ifndef _SYS_SYSPROTO_H_
1428 struct osigblock_args {
1433 osigblock(struct thread *td, struct osigblock_args *uap)
1437 OSIG2SIG(uap->mask, set);
1438 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1439 SIG2OSIG(oset, td->td_retval[0]);
1443 #ifndef _SYS_SYSPROTO_H_
1444 struct osigsetmask_args {
1449 osigsetmask(struct thread *td, struct osigsetmask_args *uap)
1453 OSIG2SIG(uap->mask, set);
1454 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1455 SIG2OSIG(oset, td->td_retval[0]);
1458 #endif /* COMPAT_43 */
1461 * Suspend calling thread until signal, providing mask to be set in the
1464 #ifndef _SYS_SYSPROTO_H_
1465 struct sigsuspend_args {
1466 const sigset_t *sigmask;
1471 sys_sigsuspend(struct thread *td, struct sigsuspend_args *uap)
1476 error = copyin(uap->sigmask, &mask, sizeof(mask));
1479 return (kern_sigsuspend(td, mask));
1483 kern_sigsuspend(struct thread *td, sigset_t mask)
1485 struct proc *p = td->td_proc;
1489 * When returning from sigsuspend, we want
1490 * the old mask to be restored after the
1491 * signal handler has finished. Thus, we
1492 * save it here and mark the sigacts structure
1496 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1497 SIGPROCMASK_PROC_LOCKED);
1498 td->td_pflags |= TDP_OLDMASK;
1501 * Process signals now. Otherwise, we can get spurious wakeup
1502 * due to signal entered process queue, but delivered to other
1503 * thread. But sigsuspend should return only on signal
1506 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1507 for (has_sig = 0; !has_sig;) {
1508 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1511 thread_suspend_check(0);
1512 mtx_lock(&p->p_sigacts->ps_mtx);
1513 while ((sig = cursig(td)) != 0) {
1514 KASSERT(sig >= 0, ("sig %d", sig));
1515 has_sig += postsig(sig);
1517 mtx_unlock(&p->p_sigacts->ps_mtx);
1520 td->td_errno = EINTR;
1521 td->td_pflags |= TDP_NERRNO;
1522 return (EJUSTRETURN);
1525 #ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1527 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1528 * convention: libc stub passes mask, not pointer, to save a copyin.
1530 #ifndef _SYS_SYSPROTO_H_
1531 struct osigsuspend_args {
1537 osigsuspend(struct thread *td, struct osigsuspend_args *uap)
1541 OSIG2SIG(uap->mask, mask);
1542 return (kern_sigsuspend(td, mask));
1544 #endif /* COMPAT_43 */
1546 #if defined(COMPAT_43)
1547 #ifndef _SYS_SYSPROTO_H_
1548 struct osigstack_args {
1549 struct sigstack *nss;
1550 struct sigstack *oss;
1555 osigstack(struct thread *td, struct osigstack_args *uap)
1557 struct sigstack nss, oss;
1560 if (uap->nss != NULL) {
1561 error = copyin(uap->nss, &nss, sizeof(nss));
1565 oss.ss_sp = td->td_sigstk.ss_sp;
1566 oss.ss_onstack = sigonstack(cpu_getstack(td));
1567 if (uap->nss != NULL) {
1568 td->td_sigstk.ss_sp = nss.ss_sp;
1569 td->td_sigstk.ss_size = 0;
1570 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1571 td->td_pflags |= TDP_ALTSTACK;
1573 if (uap->oss != NULL)
1574 error = copyout(&oss, uap->oss, sizeof(oss));
1578 #endif /* COMPAT_43 */
1580 #ifndef _SYS_SYSPROTO_H_
1581 struct sigaltstack_args {
1588 sys_sigaltstack(struct thread *td, struct sigaltstack_args *uap)
1593 if (uap->ss != NULL) {
1594 error = copyin(uap->ss, &ss, sizeof(ss));
1598 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1599 (uap->oss != NULL) ? &oss : NULL);
1602 if (uap->oss != NULL)
1603 error = copyout(&oss, uap->oss, sizeof(stack_t));
1608 kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1610 struct proc *p = td->td_proc;
1613 oonstack = sigonstack(cpu_getstack(td));
1616 *oss = td->td_sigstk;
1617 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1618 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1624 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1626 if (!(ss->ss_flags & SS_DISABLE)) {
1627 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1630 td->td_sigstk = *ss;
1631 td->td_pflags |= TDP_ALTSTACK;
1633 td->td_pflags &= ~TDP_ALTSTACK;
1640 * Common code for kill process group/broadcast kill.
1641 * cp is calling process.
1644 killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1656 sx_slock(&allproc_lock);
1657 FOREACH_PROC_IN_SYSTEM(p) {
1659 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1660 p == td->td_proc || p->p_state == PRS_NEW) {
1664 err = p_cansignal(td, p, sig);
1667 pksignal(p, sig, ksi);
1670 else if (ret == ESRCH)
1674 sx_sunlock(&allproc_lock);
1676 sx_slock(&proctree_lock);
1679 * zero pgid means send to my process group.
1681 pgrp = td->td_proc->p_pgrp;
1684 pgrp = pgfind(pgid);
1686 sx_sunlock(&proctree_lock);
1690 sx_sunlock(&proctree_lock);
1691 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1693 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1694 p->p_state == PRS_NEW) {
1698 err = p_cansignal(td, p, sig);
1701 pksignal(p, sig, ksi);
1704 else if (ret == ESRCH)
1713 #ifndef _SYS_SYSPROTO_H_
1721 sys_kill(struct thread *td, struct kill_args *uap)
1728 * A process in capability mode can send signals only to himself.
1729 * The main rationale behind this is that abort(3) is implemented as
1730 * kill(getpid(), SIGABRT).
1732 if (IN_CAPABILITY_MODE(td) && uap->pid != td->td_proc->p_pid)
1735 AUDIT_ARG_SIGNUM(uap->signum);
1736 AUDIT_ARG_PID(uap->pid);
1737 if ((u_int)uap->signum > _SIG_MAXSIG)
1740 ksiginfo_init(&ksi);
1741 ksi.ksi_signo = uap->signum;
1742 ksi.ksi_code = SI_USER;
1743 ksi.ksi_pid = td->td_proc->p_pid;
1744 ksi.ksi_uid = td->td_ucred->cr_ruid;
1747 /* kill single process */
1748 if ((p = pfind(uap->pid)) == NULL) {
1749 if ((p = zpfind(uap->pid)) == NULL)
1752 AUDIT_ARG_PROCESS(p);
1753 error = p_cansignal(td, p, uap->signum);
1754 if (error == 0 && uap->signum)
1755 pksignal(p, uap->signum, &ksi);
1760 case -1: /* broadcast signal */
1761 return (killpg1(td, uap->signum, 0, 1, &ksi));
1762 case 0: /* signal own process group */
1763 return (killpg1(td, uap->signum, 0, 0, &ksi));
1764 default: /* negative explicit process group */
1765 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1771 sys_pdkill(struct thread *td, struct pdkill_args *uap)
1774 cap_rights_t rights;
1777 AUDIT_ARG_SIGNUM(uap->signum);
1778 AUDIT_ARG_FD(uap->fd);
1779 if ((u_int)uap->signum > _SIG_MAXSIG)
1782 error = procdesc_find(td, uap->fd,
1783 cap_rights_init(&rights, CAP_PDKILL), &p);
1786 AUDIT_ARG_PROCESS(p);
1787 error = p_cansignal(td, p, uap->signum);
1788 if (error == 0 && uap->signum)
1789 kern_psignal(p, uap->signum);
1794 #if defined(COMPAT_43)
1795 #ifndef _SYS_SYSPROTO_H_
1796 struct okillpg_args {
1803 okillpg(struct thread *td, struct okillpg_args *uap)
1807 AUDIT_ARG_SIGNUM(uap->signum);
1808 AUDIT_ARG_PID(uap->pgid);
1809 if ((u_int)uap->signum > _SIG_MAXSIG)
1812 ksiginfo_init(&ksi);
1813 ksi.ksi_signo = uap->signum;
1814 ksi.ksi_code = SI_USER;
1815 ksi.ksi_pid = td->td_proc->p_pid;
1816 ksi.ksi_uid = td->td_ucred->cr_ruid;
1817 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1819 #endif /* COMPAT_43 */
1821 #ifndef _SYS_SYSPROTO_H_
1822 struct sigqueue_args {
1825 /* union sigval */ void *value;
1829 sys_sigqueue(struct thread *td, struct sigqueue_args *uap)
1835 if ((u_int)uap->signum > _SIG_MAXSIG)
1839 * Specification says sigqueue can only send signal to
1845 if ((p = pfind(uap->pid)) == NULL) {
1846 if ((p = zpfind(uap->pid)) == NULL)
1849 error = p_cansignal(td, p, uap->signum);
1850 if (error == 0 && uap->signum != 0) {
1851 ksiginfo_init(&ksi);
1852 ksi.ksi_flags = KSI_SIGQ;
1853 ksi.ksi_signo = uap->signum;
1854 ksi.ksi_code = SI_QUEUE;
1855 ksi.ksi_pid = td->td_proc->p_pid;
1856 ksi.ksi_uid = td->td_ucred->cr_ruid;
1857 ksi.ksi_value.sival_ptr = uap->value;
1858 error = pksignal(p, ksi.ksi_signo, &ksi);
1865 * Send a signal to a process group.
1868 gsignal(int pgid, int sig, ksiginfo_t *ksi)
1873 sx_slock(&proctree_lock);
1874 pgrp = pgfind(pgid);
1875 sx_sunlock(&proctree_lock);
1877 pgsignal(pgrp, sig, 0, ksi);
1884 * Send a signal to a process group. If checktty is 1,
1885 * limit to members which have a controlling terminal.
1888 pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1893 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1894 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1896 if (p->p_state == PRS_NORMAL &&
1897 (checkctty == 0 || p->p_flag & P_CONTROLT))
1898 pksignal(p, sig, ksi);
1906 * Recalculate the signal mask and reset the signal disposition after
1907 * usermode frame for delivery is formed. Should be called after
1908 * mach-specific routine, because sysent->sv_sendsig() needs correct
1909 * ps_siginfo and signal mask.
1912 postsig_done(int sig, struct thread *td, struct sigacts *ps)
1916 mtx_assert(&ps->ps_mtx, MA_OWNED);
1917 td->td_ru.ru_nsignals++;
1918 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1919 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1920 SIGADDSET(mask, sig);
1921 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1922 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1923 if (SIGISMEMBER(ps->ps_sigreset, sig))
1929 * Send a signal caused by a trap to the current thread. If it will be
1930 * caught immediately, deliver it with correct code. Otherwise, post it
1934 trapsignal(struct thread *td, ksiginfo_t *ksi)
1942 sig = ksi->ksi_signo;
1943 code = ksi->ksi_code;
1944 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1948 mtx_lock(&ps->ps_mtx);
1949 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1950 !SIGISMEMBER(td->td_sigmask, sig)) {
1952 if (KTRPOINT(curthread, KTR_PSIG))
1953 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1954 &td->td_sigmask, code);
1956 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1957 ksi, &td->td_sigmask);
1958 postsig_done(sig, td, ps);
1959 mtx_unlock(&ps->ps_mtx);
1962 * Avoid a possible infinite loop if the thread
1963 * masking the signal or process is ignoring the
1966 if (kern_forcesigexit &&
1967 (SIGISMEMBER(td->td_sigmask, sig) ||
1968 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1969 SIGDELSET(td->td_sigmask, sig);
1970 SIGDELSET(ps->ps_sigcatch, sig);
1971 SIGDELSET(ps->ps_sigignore, sig);
1972 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1974 mtx_unlock(&ps->ps_mtx);
1975 p->p_code = code; /* XXX for core dump/debugger */
1976 p->p_sig = sig; /* XXX to verify code */
1977 tdsendsignal(p, td, sig, ksi);
1982 static struct thread *
1983 sigtd(struct proc *p, int sig, int prop)
1985 struct thread *td, *signal_td;
1987 PROC_LOCK_ASSERT(p, MA_OWNED);
1990 * Check if current thread can handle the signal without
1991 * switching context to another thread.
1993 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1996 FOREACH_THREAD_IN_PROC(p, td) {
1997 if (!SIGISMEMBER(td->td_sigmask, sig)) {
2002 if (signal_td == NULL)
2003 signal_td = FIRST_THREAD_IN_PROC(p);
2008 * Send the signal to the process. If the signal has an action, the action
2009 * is usually performed by the target process rather than the caller; we add
2010 * the signal to the set of pending signals for the process.
2013 * o When a stop signal is sent to a sleeping process that takes the
2014 * default action, the process is stopped without awakening it.
2015 * o SIGCONT restarts stopped processes (or puts them back to sleep)
2016 * regardless of the signal action (eg, blocked or ignored).
2018 * Other ignored signals are discarded immediately.
2020 * NB: This function may be entered from the debugger via the "kill" DDB
2021 * command. There is little that can be done to mitigate the possibly messy
2022 * side effects of this unwise possibility.
2025 kern_psignal(struct proc *p, int sig)
2029 ksiginfo_init(&ksi);
2030 ksi.ksi_signo = sig;
2031 ksi.ksi_code = SI_KERNEL;
2032 (void) tdsendsignal(p, NULL, sig, &ksi);
2036 pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
2039 return (tdsendsignal(p, NULL, sig, ksi));
2042 /* Utility function for finding a thread to send signal event to. */
2044 sigev_findtd(struct proc *p ,struct sigevent *sigev, struct thread **ttd)
2048 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
2049 td = tdfind(sigev->sigev_notify_thread_id, p->p_pid);
2061 tdsignal(struct thread *td, int sig)
2065 ksiginfo_init(&ksi);
2066 ksi.ksi_signo = sig;
2067 ksi.ksi_code = SI_KERNEL;
2068 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2072 tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2075 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2079 tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2082 sigqueue_t *sigqueue;
2089 MPASS(td == NULL || p == td->td_proc);
2090 PROC_LOCK_ASSERT(p, MA_OWNED);
2092 if (!_SIG_VALID(sig))
2093 panic("%s(): invalid signal %d", __func__, sig);
2095 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("%s: ksi on queue", __func__));
2098 * IEEE Std 1003.1-2001: return success when killing a zombie.
2100 if (p->p_state == PRS_ZOMBIE) {
2101 if (ksi && (ksi->ksi_flags & KSI_INS))
2102 ksiginfo_tryfree(ksi);
2107 KNOTE_LOCKED(p->p_klist, NOTE_SIGNAL | sig);
2108 prop = sigprop(sig);
2111 td = sigtd(p, sig, prop);
2112 sigqueue = &p->p_sigqueue;
2114 sigqueue = &td->td_sigqueue;
2116 SDT_PROBE3(proc, , , signal__send, td, p, sig);
2119 * If the signal is being ignored,
2120 * then we forget about it immediately.
2121 * (Note: we don't set SIGCONT in ps_sigignore,
2122 * and if it is set to SIG_IGN,
2123 * action will be SIG_DFL here.)
2125 mtx_lock(&ps->ps_mtx);
2126 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2127 SDT_PROBE3(proc, , , signal__discard, td, p, sig);
2129 mtx_unlock(&ps->ps_mtx);
2130 if (ksi && (ksi->ksi_flags & KSI_INS))
2131 ksiginfo_tryfree(ksi);
2134 if (SIGISMEMBER(td->td_sigmask, sig))
2136 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2140 if (SIGISMEMBER(ps->ps_sigintr, sig))
2144 mtx_unlock(&ps->ps_mtx);
2146 if (prop & SIGPROP_CONT)
2147 sigqueue_delete_stopmask_proc(p);
2148 else if (prop & SIGPROP_STOP) {
2150 * If sending a tty stop signal to a member of an orphaned
2151 * process group, discard the signal here if the action
2152 * is default; don't stop the process below if sleeping,
2153 * and don't clear any pending SIGCONT.
2155 if ((prop & SIGPROP_TTYSTOP) &&
2156 (p->p_pgrp->pg_jobc == 0) &&
2157 (action == SIG_DFL)) {
2158 if (ksi && (ksi->ksi_flags & KSI_INS))
2159 ksiginfo_tryfree(ksi);
2162 sigqueue_delete_proc(p, SIGCONT);
2163 if (p->p_flag & P_CONTINUED) {
2164 p->p_flag &= ~P_CONTINUED;
2165 PROC_LOCK(p->p_pptr);
2166 sigqueue_take(p->p_ksi);
2167 PROC_UNLOCK(p->p_pptr);
2171 ret = sigqueue_add(sigqueue, sig, ksi);
2176 * Defer further processing for signals which are held,
2177 * except that stopped processes must be continued by SIGCONT.
2179 if (action == SIG_HOLD &&
2180 !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
2183 /* SIGKILL: Remove procfs STOPEVENTs. */
2184 if (sig == SIGKILL) {
2185 /* from procfs_ioctl.c: PIOCBIC */
2187 /* from procfs_ioctl.c: PIOCCONT */
2192 * Some signals have a process-wide effect and a per-thread
2193 * component. Most processing occurs when the process next
2194 * tries to cross the user boundary, however there are some
2195 * times when processing needs to be done immediately, such as
2196 * waking up threads so that they can cross the user boundary.
2197 * We try to do the per-process part here.
2199 if (P_SHOULDSTOP(p)) {
2200 KASSERT(!(p->p_flag & P_WEXIT),
2201 ("signal to stopped but exiting process"));
2202 if (sig == SIGKILL) {
2204 * If traced process is already stopped,
2205 * then no further action is necessary.
2207 if (p->p_flag & P_TRACED)
2210 * SIGKILL sets process running.
2211 * It will die elsewhere.
2212 * All threads must be restarted.
2214 p->p_flag &= ~P_STOPPED_SIG;
2218 if (prop & SIGPROP_CONT) {
2220 * If traced process is already stopped,
2221 * then no further action is necessary.
2223 if (p->p_flag & P_TRACED)
2226 * If SIGCONT is default (or ignored), we continue the
2227 * process but don't leave the signal in sigqueue as
2228 * it has no further action. If SIGCONT is held, we
2229 * continue the process and leave the signal in
2230 * sigqueue. If the process catches SIGCONT, let it
2231 * handle the signal itself. If it isn't waiting on
2232 * an event, it goes back to run state.
2233 * Otherwise, process goes back to sleep state.
2235 p->p_flag &= ~P_STOPPED_SIG;
2237 if (p->p_numthreads == p->p_suspcount) {
2239 p->p_flag |= P_CONTINUED;
2240 p->p_xsig = SIGCONT;
2241 PROC_LOCK(p->p_pptr);
2242 childproc_continued(p);
2243 PROC_UNLOCK(p->p_pptr);
2246 if (action == SIG_DFL) {
2247 thread_unsuspend(p);
2249 sigqueue_delete(sigqueue, sig);
2252 if (action == SIG_CATCH) {
2254 * The process wants to catch it so it needs
2255 * to run at least one thread, but which one?
2261 * The signal is not ignored or caught.
2263 thread_unsuspend(p);
2268 if (prop & SIGPROP_STOP) {
2270 * If traced process is already stopped,
2271 * then no further action is necessary.
2273 if (p->p_flag & P_TRACED)
2276 * Already stopped, don't need to stop again
2277 * (If we did the shell could get confused).
2278 * Just make sure the signal STOP bit set.
2280 p->p_flag |= P_STOPPED_SIG;
2281 sigqueue_delete(sigqueue, sig);
2286 * All other kinds of signals:
2287 * If a thread is sleeping interruptibly, simulate a
2288 * wakeup so that when it is continued it will be made
2289 * runnable and can look at the signal. However, don't make
2290 * the PROCESS runnable, leave it stopped.
2291 * It may run a bit until it hits a thread_suspend_check().
2296 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2297 wakeup_swapper = sleepq_abort(td, intrval);
2304 * Mutexes are short lived. Threads waiting on them will
2305 * hit thread_suspend_check() soon.
2307 } else if (p->p_state == PRS_NORMAL) {
2308 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2309 tdsigwakeup(td, sig, action, intrval);
2313 MPASS(action == SIG_DFL);
2315 if (prop & SIGPROP_STOP) {
2316 if (p->p_flag & (P_PPWAIT|P_WEXIT))
2318 p->p_flag |= P_STOPPED_SIG;
2321 wakeup_swapper = sig_suspend_threads(td, p, 1);
2322 if (p->p_numthreads == p->p_suspcount) {
2324 * only thread sending signal to another
2325 * process can reach here, if thread is sending
2326 * signal to its process, because thread does
2327 * not suspend itself here, p_numthreads
2328 * should never be equal to p_suspcount.
2332 sigqueue_delete_proc(p, p->p_xsig);
2340 /* Not in "NORMAL" state. discard the signal. */
2341 sigqueue_delete(sigqueue, sig);
2346 * The process is not stopped so we need to apply the signal to all the
2350 tdsigwakeup(td, sig, action, intrval);
2352 thread_unsuspend(p);
2355 /* If we jump here, proc slock should not be owned. */
2356 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2361 * The force of a signal has been directed against a single
2362 * thread. We need to see what we can do about knocking it
2363 * out of any sleep it may be in etc.
2366 tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2368 struct proc *p = td->td_proc;
2373 PROC_LOCK_ASSERT(p, MA_OWNED);
2374 prop = sigprop(sig);
2379 * Bring the priority of a thread up if we want it to get
2380 * killed in this lifetime. Be careful to avoid bumping the
2381 * priority of the idle thread, since we still allow to signal
2384 if (action == SIG_DFL && (prop & SIGPROP_KILL) != 0 &&
2385 td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2386 sched_prio(td, PUSER);
2387 if (TD_ON_SLEEPQ(td)) {
2389 * If thread is sleeping uninterruptibly
2390 * we can't interrupt the sleep... the signal will
2391 * be noticed when the process returns through
2392 * trap() or syscall().
2394 if ((td->td_flags & TDF_SINTR) == 0)
2397 * If SIGCONT is default (or ignored) and process is
2398 * asleep, we are finished; the process should not
2401 if ((prop & SIGPROP_CONT) && action == SIG_DFL) {
2404 sigqueue_delete(&p->p_sigqueue, sig);
2406 * It may be on either list in this state.
2407 * Remove from both for now.
2409 sigqueue_delete(&td->td_sigqueue, sig);
2414 * Don't awaken a sleeping thread for SIGSTOP if the
2415 * STOP signal is deferred.
2417 if ((prop & SIGPROP_STOP) != 0 && (td->td_flags & (TDF_SBDRY |
2418 TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2422 * Give low priority threads a better chance to run.
2424 if (td->td_priority > PUSER && !TD_IS_IDLETHREAD(td))
2425 sched_prio(td, PUSER);
2427 wakeup_swapper = sleepq_abort(td, intrval);
2430 * Other states do nothing with the signal immediately,
2431 * other than kicking ourselves if we are running.
2432 * It will either never be noticed, or noticed very soon.
2435 if (TD_IS_RUNNING(td) && td != curthread)
2447 sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2452 PROC_LOCK_ASSERT(p, MA_OWNED);
2453 PROC_SLOCK_ASSERT(p, MA_OWNED);
2456 FOREACH_THREAD_IN_PROC(p, td2) {
2458 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2459 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2460 (td2->td_flags & TDF_SINTR)) {
2461 if (td2->td_flags & TDF_SBDRY) {
2463 * Once a thread is asleep with
2464 * TDF_SBDRY and without TDF_SERESTART
2465 * or TDF_SEINTR set, it should never
2466 * become suspended due to this check.
2468 KASSERT(!TD_IS_SUSPENDED(td2),
2469 ("thread with deferred stops suspended"));
2470 if (TD_SBDRY_INTR(td2) && sending) {
2471 wakeup_swapper |= sleepq_abort(td2,
2472 TD_SBDRY_ERRNO(td2));
2474 } else if (!TD_IS_SUSPENDED(td2)) {
2475 thread_suspend_one(td2);
2477 } else if (!TD_IS_SUSPENDED(td2)) {
2478 if (sending || td != td2)
2479 td2->td_flags |= TDF_ASTPENDING;
2481 if (TD_IS_RUNNING(td2) && td2 != td)
2482 forward_signal(td2);
2487 return (wakeup_swapper);
2491 * Stop the process for an event deemed interesting to the debugger. If si is
2492 * non-NULL, this is a signal exchange; the new signal requested by the
2493 * debugger will be returned for handling. If si is NULL, this is some other
2494 * type of interesting event. The debugger may request a signal be delivered in
2495 * that case as well, however it will be deferred until it can be handled.
2498 ptracestop(struct thread *td, int sig, ksiginfo_t *si)
2500 struct proc *p = td->td_proc;
2505 PROC_LOCK_ASSERT(p, MA_OWNED);
2506 KASSERT(!(p->p_flag & P_WEXIT), ("Stopping exiting process"));
2507 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2508 &p->p_mtx.lock_object, "Stopping for traced signal");
2512 if (si == NULL || (si->ksi_flags & KSI_PTRACE) == 0) {
2513 td->td_dbgflags |= TDB_XSIG;
2514 CTR4(KTR_PTRACE, "ptracestop: tid %d (pid %d) flags %#x sig %d",
2515 td->td_tid, p->p_pid, td->td_dbgflags, sig);
2517 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2520 * Ensure that, if we've been PT_KILLed, the
2521 * exit status reflects that. Another thread
2522 * may also be in ptracestop(), having just
2523 * received the SIGKILL, but this thread was
2524 * unsuspended first.
2526 td->td_dbgflags &= ~TDB_XSIG;
2527 td->td_xsig = SIGKILL;
2531 if (p->p_flag & P_SINGLE_EXIT &&
2532 !(td->td_dbgflags & TDB_EXIT)) {
2534 * Ignore ptrace stops except for thread exit
2535 * events when the process exits.
2537 td->td_dbgflags &= ~TDB_XSIG;
2543 * Make wait(2) work. Ensure that right after the
2544 * attach, the thread which was decided to become the
2545 * leader of attach gets reported to the waiter.
2546 * Otherwise, just avoid overwriting another thread's
2547 * assignment to p_xthread. If another thread has
2548 * already set p_xthread, the current thread will get
2549 * a chance to report itself upon the next iteration.
2551 if ((td->td_dbgflags & TDB_FSTP) != 0 ||
2552 ((p->p_flag2 & P2_PTRACE_FSTP) == 0 &&
2553 p->p_xthread == NULL)) {
2556 td->td_dbgflags &= ~TDB_FSTP;
2557 p->p_flag2 &= ~P2_PTRACE_FSTP;
2558 p->p_flag |= P_STOPPED_SIG | P_STOPPED_TRACE;
2559 sig_suspend_threads(td, p, 0);
2561 if ((td->td_dbgflags & TDB_STOPATFORK) != 0) {
2562 td->td_dbgflags &= ~TDB_STOPATFORK;
2563 cv_broadcast(&p->p_dbgwait);
2566 thread_suspend_switch(td, p);
2567 if (p->p_xthread == td)
2568 p->p_xthread = NULL;
2569 if (!(p->p_flag & P_TRACED))
2571 if (td->td_dbgflags & TDB_SUSPEND) {
2572 if (p->p_flag & P_SINGLE_EXIT)
2580 if (si != NULL && sig == td->td_xsig) {
2581 /* Parent wants us to take the original signal unchanged. */
2582 si->ksi_flags |= KSI_HEAD;
2583 if (sigqueue_add(&td->td_sigqueue, sig, si) != 0)
2585 } else if (td->td_xsig != 0) {
2587 * If parent wants us to take a new signal, then it will leave
2588 * it in td->td_xsig; otherwise we just look for signals again.
2590 ksiginfo_init(&ksi);
2591 ksi.ksi_signo = td->td_xsig;
2592 ksi.ksi_flags |= KSI_PTRACE;
2593 prop = sigprop(td->td_xsig);
2594 td2 = sigtd(p, td->td_xsig, prop);
2595 tdsendsignal(p, td2, td->td_xsig, &ksi);
2600 return (td->td_xsig);
2604 reschedule_signals(struct proc *p, sigset_t block, int flags)
2610 PROC_LOCK_ASSERT(p, MA_OWNED);
2612 mtx_assert(&ps->ps_mtx, (flags & SIGPROCMASK_PS_LOCKED) != 0 ?
2613 MA_OWNED : MA_NOTOWNED);
2614 if (SIGISEMPTY(p->p_siglist))
2616 SIGSETAND(block, p->p_siglist);
2617 while ((sig = sig_ffs(&block)) != 0) {
2618 SIGDELSET(block, sig);
2619 td = sigtd(p, sig, 0);
2621 if (!(flags & SIGPROCMASK_PS_LOCKED))
2622 mtx_lock(&ps->ps_mtx);
2623 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, sig))
2624 tdsigwakeup(td, sig, SIG_CATCH,
2625 (SIGISMEMBER(ps->ps_sigintr, sig) ? EINTR :
2627 if (!(flags & SIGPROCMASK_PS_LOCKED))
2628 mtx_unlock(&ps->ps_mtx);
2633 tdsigcleanup(struct thread *td)
2639 PROC_LOCK_ASSERT(p, MA_OWNED);
2641 sigqueue_flush(&td->td_sigqueue);
2642 if (p->p_numthreads == 1)
2646 * Since we cannot handle signals, notify signal post code
2647 * about this by filling the sigmask.
2649 * Also, if needed, wake up thread(s) that do not block the
2650 * same signals as the exiting thread, since the thread might
2651 * have been selected for delivery and woken up.
2653 SIGFILLSET(unblocked);
2654 SIGSETNAND(unblocked, td->td_sigmask);
2655 SIGFILLSET(td->td_sigmask);
2656 reschedule_signals(p, unblocked, 0);
2661 sigdeferstop_curr_flags(int cflags)
2664 MPASS((cflags & (TDF_SEINTR | TDF_SERESTART)) == 0 ||
2665 (cflags & TDF_SBDRY) != 0);
2666 return (cflags & (TDF_SBDRY | TDF_SEINTR | TDF_SERESTART));
2670 * Defer the delivery of SIGSTOP for the current thread, according to
2671 * the requested mode. Returns previous flags, which must be restored
2672 * by sigallowstop().
2674 * TDF_SBDRY, TDF_SEINTR, and TDF_SERESTART flags are only set and
2675 * cleared by the current thread, which allow the lock-less read-only
2679 sigdeferstop_impl(int mode)
2685 cflags = sigdeferstop_curr_flags(td->td_flags);
2687 case SIGDEFERSTOP_NOP:
2690 case SIGDEFERSTOP_OFF:
2693 case SIGDEFERSTOP_SILENT:
2694 nflags = (cflags | TDF_SBDRY) & ~(TDF_SEINTR | TDF_SERESTART);
2696 case SIGDEFERSTOP_EINTR:
2697 nflags = (cflags | TDF_SBDRY | TDF_SEINTR) & ~TDF_SERESTART;
2699 case SIGDEFERSTOP_ERESTART:
2700 nflags = (cflags | TDF_SBDRY | TDF_SERESTART) & ~TDF_SEINTR;
2703 panic("sigdeferstop: invalid mode %x", mode);
2706 if (cflags == nflags)
2707 return (SIGDEFERSTOP_VAL_NCHG);
2709 td->td_flags = (td->td_flags & ~cflags) | nflags;
2715 * Restores the STOP handling mode, typically permitting the delivery
2716 * of SIGSTOP for the current thread. This does not immediately
2717 * suspend if a stop was posted. Instead, the thread will suspend
2718 * either via ast() or a subsequent interruptible sleep.
2721 sigallowstop_impl(int prev)
2726 KASSERT(prev != SIGDEFERSTOP_VAL_NCHG, ("failed sigallowstop"));
2727 KASSERT((prev & ~(TDF_SBDRY | TDF_SEINTR | TDF_SERESTART)) == 0,
2728 ("sigallowstop: incorrect previous mode %x", prev));
2730 cflags = sigdeferstop_curr_flags(td->td_flags);
2731 if (cflags != prev) {
2733 td->td_flags = (td->td_flags & ~cflags) | prev;
2739 * If the current process has received a signal (should be caught or cause
2740 * termination, should interrupt current syscall), return the signal number.
2741 * Stop signals with default action are processed immediately, then cleared;
2742 * they aren't returned. This is checked after each entry to the system for
2743 * a syscall or trap (though this can usually be done without calling issignal
2744 * by checking the pending signal masks in cursig.) The normal call
2747 * while (sig = cursig(curthread))
2751 issignal(struct thread *td)
2755 struct sigqueue *queue;
2756 sigset_t sigpending;
2761 mtx_assert(&ps->ps_mtx, MA_OWNED);
2762 PROC_LOCK_ASSERT(p, MA_OWNED);
2764 int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
2766 sigpending = td->td_sigqueue.sq_signals;
2767 SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
2768 SIGSETNAND(sigpending, td->td_sigmask);
2770 if ((p->p_flag & P_PPWAIT) != 0 || (td->td_flags &
2771 (TDF_SBDRY | TDF_SERESTART | TDF_SEINTR)) == TDF_SBDRY)
2772 SIG_STOPSIGMASK(sigpending);
2773 if (SIGISEMPTY(sigpending)) /* no signal to send */
2775 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED &&
2776 (p->p_flag2 & P2_PTRACE_FSTP) != 0 &&
2777 SIGISMEMBER(sigpending, SIGSTOP)) {
2779 * If debugger just attached, always consume
2780 * SIGSTOP from ptrace(PT_ATTACH) first, to
2781 * execute the debugger attach ritual in
2785 td->td_dbgflags |= TDB_FSTP;
2787 sig = sig_ffs(&sigpending);
2790 if (p->p_stops & S_SIG) {
2791 mtx_unlock(&ps->ps_mtx);
2792 stopevent(p, S_SIG, sig);
2793 mtx_lock(&ps->ps_mtx);
2797 * We should see pending but ignored signals
2798 * only if P_TRACED was on when they were posted.
2800 if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
2801 sigqueue_delete(&td->td_sigqueue, sig);
2802 sigqueue_delete(&p->p_sigqueue, sig);
2805 if ((p->p_flag & (P_TRACED | P_PPTRACE)) == P_TRACED) {
2807 * If traced, always stop.
2808 * Remove old signal from queue before the stop.
2809 * XXX shrug off debugger, it causes siginfo to
2812 queue = &td->td_sigqueue;
2813 td->td_dbgksi.ksi_signo = 0;
2814 if (sigqueue_get(queue, sig, &td->td_dbgksi) == 0) {
2815 queue = &p->p_sigqueue;
2816 sigqueue_get(queue, sig, &td->td_dbgksi);
2819 mtx_unlock(&ps->ps_mtx);
2820 sig = ptracestop(td, sig, &td->td_dbgksi);
2821 mtx_lock(&ps->ps_mtx);
2824 * Keep looking if the debugger discarded the signal
2825 * or replaced it with a masked signal.
2827 * If the traced bit got turned off, go back up
2828 * to the top to rescan signals. This ensures
2829 * that p_sig* and p_sigact are consistent.
2831 if (sig == 0 || (p->p_flag & P_TRACED) == 0)
2835 prop = sigprop(sig);
2838 * Decide whether the signal should be returned.
2839 * Return the signal's number, or fall through
2840 * to clear it from the pending mask.
2842 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2844 case (intptr_t)SIG_DFL:
2846 * Don't take default actions on system processes.
2848 if (p->p_pid <= 1) {
2851 * Are you sure you want to ignore SIGSEGV
2854 printf("Process (pid %lu) got signal %d\n",
2855 (u_long)p->p_pid, sig);
2857 break; /* == ignore */
2860 * If there is a pending stop signal to process with
2861 * default action, stop here, then clear the signal.
2862 * Traced or exiting processes should ignore stops.
2863 * Additionally, a member of an orphaned process group
2864 * should ignore tty stops.
2866 if (prop & SIGPROP_STOP) {
2868 (P_TRACED | P_WEXIT | P_SINGLE_EXIT) ||
2869 (p->p_pgrp->pg_jobc == 0 &&
2870 prop & SIGPROP_TTYSTOP))
2871 break; /* == ignore */
2872 if (TD_SBDRY_INTR(td)) {
2873 KASSERT((td->td_flags & TDF_SBDRY) != 0,
2874 ("lost TDF_SBDRY"));
2877 mtx_unlock(&ps->ps_mtx);
2878 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2879 &p->p_mtx.lock_object, "Catching SIGSTOP");
2880 sigqueue_delete(&td->td_sigqueue, sig);
2881 sigqueue_delete(&p->p_sigqueue, sig);
2882 p->p_flag |= P_STOPPED_SIG;
2885 sig_suspend_threads(td, p, 0);
2886 thread_suspend_switch(td, p);
2888 mtx_lock(&ps->ps_mtx);
2890 } else if (prop & SIGPROP_IGNORE) {
2892 * Except for SIGCONT, shouldn't get here.
2893 * Default action is to ignore; drop it.
2895 break; /* == ignore */
2900 case (intptr_t)SIG_IGN:
2902 * Masking above should prevent us ever trying
2903 * to take action on an ignored signal other
2904 * than SIGCONT, unless process is traced.
2906 if ((prop & SIGPROP_CONT) == 0 &&
2907 (p->p_flag & P_TRACED) == 0)
2908 printf("issignal\n");
2909 break; /* == ignore */
2913 * This signal has an action, let
2914 * postsig() process it.
2918 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2919 sigqueue_delete(&p->p_sigqueue, sig);
2926 thread_stopped(struct proc *p)
2930 PROC_LOCK_ASSERT(p, MA_OWNED);
2931 PROC_SLOCK_ASSERT(p, MA_OWNED);
2935 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2937 p->p_flag &= ~P_WAITED;
2938 PROC_LOCK(p->p_pptr);
2939 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2940 CLD_TRAPPED : CLD_STOPPED);
2941 PROC_UNLOCK(p->p_pptr);
2947 * Take the action for the specified signal
2948 * from the current set of pending signals.
2954 struct thread *td = curthread;
2955 struct proc *p = td->td_proc;
2959 sigset_t returnmask;
2961 KASSERT(sig != 0, ("postsig"));
2963 PROC_LOCK_ASSERT(p, MA_OWNED);
2965 mtx_assert(&ps->ps_mtx, MA_OWNED);
2966 ksiginfo_init(&ksi);
2967 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2968 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2970 ksi.ksi_signo = sig;
2971 if (ksi.ksi_code == SI_TIMER)
2972 itimer_accept(p, ksi.ksi_timerid, &ksi);
2973 action = ps->ps_sigact[_SIG_IDX(sig)];
2975 if (KTRPOINT(td, KTR_PSIG))
2976 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2977 &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
2979 if (p->p_stops & S_SIG) {
2980 mtx_unlock(&ps->ps_mtx);
2981 stopevent(p, S_SIG, sig);
2982 mtx_lock(&ps->ps_mtx);
2985 if (action == SIG_DFL) {
2987 * Default action, where the default is to kill
2988 * the process. (Other cases were ignored above.)
2990 mtx_unlock(&ps->ps_mtx);
2995 * If we get here, the signal must be caught.
2997 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2998 ("postsig action"));
3000 * Set the new mask value and also defer further
3001 * occurrences of this signal.
3003 * Special case: user has done a sigsuspend. Here the
3004 * current mask is not of interest, but rather the
3005 * mask from before the sigsuspend is what we want
3006 * restored after the signal processing is completed.
3008 if (td->td_pflags & TDP_OLDMASK) {
3009 returnmask = td->td_oldsigmask;
3010 td->td_pflags &= ~TDP_OLDMASK;
3012 returnmask = td->td_sigmask;
3014 if (p->p_sig == sig) {
3018 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
3019 postsig_done(sig, td, ps);
3025 * Kill the current process for stated reason.
3028 killproc(struct proc *p, char *why)
3031 PROC_LOCK_ASSERT(p, MA_OWNED);
3032 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)", p, p->p_pid,
3034 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid,
3035 p->p_comm, p->p_ucred ? p->p_ucred->cr_uid : -1, why);
3036 p->p_flag |= P_WKILLED;
3037 kern_psignal(p, SIGKILL);
3041 * Force the current process to exit with the specified signal, dumping core
3042 * if appropriate. We bypass the normal tests for masked and caught signals,
3043 * allowing unrecoverable failures to terminate the process without changing
3044 * signal state. Mark the accounting record with the signal termination.
3045 * If dumping core, save the signal number for the debugger. Calls exit and
3049 sigexit(struct thread *td, int sig)
3051 struct proc *p = td->td_proc;
3053 PROC_LOCK_ASSERT(p, MA_OWNED);
3054 p->p_acflag |= AXSIG;
3056 * We must be single-threading to generate a core dump. This
3057 * ensures that the registers in the core file are up-to-date.
3058 * Also, the ELF dump handler assumes that the thread list doesn't
3059 * change out from under it.
3061 * XXX If another thread attempts to single-thread before us
3062 * (e.g. via fork()), we won't get a dump at all.
3064 if ((sigprop(sig) & SIGPROP_CORE) &&
3065 thread_single(p, SINGLE_NO_EXIT) == 0) {
3068 * Log signals which would cause core dumps
3069 * (Log as LOG_INFO to appease those who don't want
3071 * XXX : Todo, as well as euid, write out ruid too
3072 * Note that coredump() drops proc lock.
3074 if (coredump(td) == 0)
3076 if (kern_logsigexit)
3078 "pid %d (%s), uid %d: exited on signal %d%s\n",
3079 p->p_pid, p->p_comm,
3080 td->td_ucred ? td->td_ucred->cr_uid : -1,
3082 sig & WCOREFLAG ? " (core dumped)" : "");
3090 * Send queued SIGCHLD to parent when child process's state
3094 sigparent(struct proc *p, int reason, int status)
3096 PROC_LOCK_ASSERT(p, MA_OWNED);
3097 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3099 if (p->p_ksi != NULL) {
3100 p->p_ksi->ksi_signo = SIGCHLD;
3101 p->p_ksi->ksi_code = reason;
3102 p->p_ksi->ksi_status = status;
3103 p->p_ksi->ksi_pid = p->p_pid;
3104 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
3105 if (KSI_ONQ(p->p_ksi))
3108 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
3112 childproc_jobstate(struct proc *p, int reason, int sig)
3116 PROC_LOCK_ASSERT(p, MA_OWNED);
3117 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
3120 * Wake up parent sleeping in kern_wait(), also send
3121 * SIGCHLD to parent, but SIGCHLD does not guarantee
3122 * that parent will awake, because parent may masked
3125 p->p_pptr->p_flag |= P_STATCHILD;
3128 ps = p->p_pptr->p_sigacts;
3129 mtx_lock(&ps->ps_mtx);
3130 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
3131 mtx_unlock(&ps->ps_mtx);
3132 sigparent(p, reason, sig);
3134 mtx_unlock(&ps->ps_mtx);
3138 childproc_stopped(struct proc *p, int reason)
3141 childproc_jobstate(p, reason, p->p_xsig);
3145 childproc_continued(struct proc *p)
3147 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
3151 childproc_exited(struct proc *p)
3155 if (WCOREDUMP(p->p_xsig)) {
3156 reason = CLD_DUMPED;
3157 status = WTERMSIG(p->p_xsig);
3158 } else if (WIFSIGNALED(p->p_xsig)) {
3159 reason = CLD_KILLED;
3160 status = WTERMSIG(p->p_xsig);
3162 reason = CLD_EXITED;
3163 status = p->p_xexit;
3166 * XXX avoid calling wakeup(p->p_pptr), the work is
3169 sigparent(p, reason, status);
3173 * We only have 1 character for the core count in the format
3174 * string, so the range will be 0-9
3176 #define MAX_NUM_CORE_FILES 10
3177 #ifndef NUM_CORE_FILES
3178 #define NUM_CORE_FILES 5
3180 CTASSERT(NUM_CORE_FILES >= 0 && NUM_CORE_FILES <= MAX_NUM_CORE_FILES);
3181 static int num_cores = NUM_CORE_FILES;
3184 sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
3189 new_val = num_cores;
3190 error = sysctl_handle_int(oidp, &new_val, 0, req);
3191 if (error != 0 || req->newptr == NULL)
3193 if (new_val > MAX_NUM_CORE_FILES)
3194 new_val = MAX_NUM_CORE_FILES;
3197 num_cores = new_val;
3200 SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
3201 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
3203 #define GZ_SUFFIX ".gz"
3206 static int compress_user_cores = 1;
3207 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RWTUN,
3208 &compress_user_cores, 0, "Compression of user corefiles");
3210 int compress_user_cores_gzlevel = 6;
3211 SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RWTUN,
3212 &compress_user_cores_gzlevel, 0, "Corefile gzip compression level");
3214 static int compress_user_cores = 0;
3218 * Protect the access to corefilename[] by allproc_lock.
3220 #define corefilename_lock allproc_lock
3222 static char corefilename[MAXPATHLEN] = {"%N.core"};
3223 TUNABLE_STR("kern.corefile", corefilename, sizeof(corefilename));
3226 sysctl_kern_corefile(SYSCTL_HANDLER_ARGS)
3230 sx_xlock(&corefilename_lock);
3231 error = sysctl_handle_string(oidp, corefilename, sizeof(corefilename),
3233 sx_xunlock(&corefilename_lock);
3237 SYSCTL_PROC(_kern, OID_AUTO, corefile, CTLTYPE_STRING | CTLFLAG_RW |
3238 CTLFLAG_MPSAFE, 0, 0, sysctl_kern_corefile, "A",
3239 "Process corefile name format string");
3242 * corefile_open(comm, uid, pid, td, compress, vpp, namep)
3243 * Expand the name described in corefilename, using name, uid, and pid
3244 * and open/create core file.
3245 * corefilename is a printf-like string, with three format specifiers:
3246 * %N name of process ("name")
3247 * %P process id (pid)
3249 * For example, "%N.core" is the default; they can be disabled completely
3250 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3251 * This is controlled by the sysctl variable kern.corefile (see above).
3254 corefile_open(const char *comm, uid_t uid, pid_t pid, struct thread *td,
3255 int compress, struct vnode **vpp, char **namep)
3257 struct nameidata nd;
3260 char *hostname, *name;
3261 int indexpos, i, error, cmode, flags, oflags;
3264 format = corefilename;
3265 name = malloc(MAXPATHLEN, M_TEMP, M_WAITOK | M_ZERO);
3267 (void)sbuf_new(&sb, name, MAXPATHLEN, SBUF_FIXEDLEN);
3268 sx_slock(&corefilename_lock);
3269 for (i = 0; format[i] != '\0'; i++) {
3270 switch (format[i]) {
3271 case '%': /* Format character */
3273 switch (format[i]) {
3275 sbuf_putc(&sb, '%');
3277 case 'H': /* hostname */
3278 if (hostname == NULL) {
3279 hostname = malloc(MAXHOSTNAMELEN,
3282 getcredhostname(td->td_ucred, hostname,
3284 sbuf_printf(&sb, "%s", hostname);
3286 case 'I': /* autoincrementing index */
3287 sbuf_printf(&sb, "0");
3288 indexpos = sbuf_len(&sb) - 1;
3290 case 'N': /* process name */
3291 sbuf_printf(&sb, "%s", comm);
3293 case 'P': /* process id */
3294 sbuf_printf(&sb, "%u", pid);
3296 case 'U': /* user id */
3297 sbuf_printf(&sb, "%u", uid);
3301 "Unknown format character %c in "
3302 "corename `%s'\n", format[i], format);
3307 sbuf_putc(&sb, format[i]);
3311 sx_sunlock(&corefilename_lock);
3312 free(hostname, M_TEMP);
3314 sbuf_printf(&sb, GZ_SUFFIX);
3315 if (sbuf_error(&sb) != 0) {
3316 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3317 "long\n", (long)pid, comm, (u_long)uid);
3325 cmode = S_IRUSR | S_IWUSR;
3326 oflags = VN_OPEN_NOAUDIT | VN_OPEN_NAMECACHE |
3327 (capmode_coredump ? VN_OPEN_NOCAPCHECK : 0);
3330 * If the core format has a %I in it, then we need to check
3331 * for existing corefiles before returning a name.
3332 * To do this we iterate over 0..num_cores to find a
3333 * non-existing core file name to use.
3335 if (indexpos != -1) {
3336 for (i = 0; i < num_cores; i++) {
3337 flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3338 name[indexpos] = '0' + i;
3339 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3340 error = vn_open_cred(&nd, &flags, cmode, oflags,
3341 td->td_ucred, NULL);
3343 if (error == EEXIST)
3346 "pid %d (%s), uid (%u): Path `%s' failed "
3347 "on initial open test, error = %d\n",
3348 pid, comm, uid, name, error);
3354 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3355 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, td);
3356 error = vn_open_cred(&nd, &flags, cmode, oflags, td->td_ucred, NULL);
3360 audit_proc_coredump(td, name, error);
3365 NDFREE(&nd, NDF_ONLY_PNBUF);
3372 coredump_sanitise_path(const char *path)
3377 * Only send a subset of ASCII to devd(8) because it
3378 * might pass these strings to sh -c.
3380 for (i = 0; path[i]; i++)
3381 if (!(isalpha(path[i]) || isdigit(path[i])) &&
3382 path[i] != '/' && path[i] != '.' &&
3390 * Dump a process' core. The main routine does some
3391 * policy checking, and creates the name of the coredump;
3392 * then it passes on a vnode and a size limit to the process-specific
3393 * coredump routine if there is one; if there _is not_ one, it returns
3394 * ENOSYS; otherwise it returns the error from the process-specific routine.
3398 coredump(struct thread *td)
3400 struct proc *p = td->td_proc;
3401 struct ucred *cred = td->td_ucred;
3405 int error, error1, locked;
3406 char *name; /* name of corefile */
3410 char *fullpath, *freepath = NULL;
3412 static const char comm_name[] = "comm=";
3413 static const char core_name[] = "core=";
3415 PROC_LOCK_ASSERT(p, MA_OWNED);
3416 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3417 _STOPEVENT(p, S_CORE, 0);
3419 if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
3420 (p->p_flag2 & P2_NOTRACE) != 0) {
3426 * Note that the bulk of limit checking is done after
3427 * the corefile is created. The exception is if the limit
3428 * for corefiles is 0, in which case we don't bother
3429 * creating the corefile at all. This layout means that
3430 * a corefile is truncated instead of not being created,
3431 * if it is larger than the limit.
3433 limit = (off_t)lim_cur(td, RLIMIT_CORE);
3434 if (limit == 0 || racct_get_available(p, RACCT_CORE) == 0) {
3440 error = corefile_open(p->p_comm, cred->cr_uid, p->p_pid, td,
3441 compress_user_cores, &vp, &name);
3446 * Don't dump to non-regular files or files with links.
3447 * Do not dump into system files.
3449 if (vp->v_type != VREG || VOP_GETATTR(vp, &vattr, cred) != 0 ||
3450 vattr.va_nlink != 1 || (vp->v_vflag & VV_SYSTEM) != 0) {
3458 /* Postpone other writers, including core dumps of other processes. */
3459 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
3461 lf.l_whence = SEEK_SET;
3464 lf.l_type = F_WRLCK;
3465 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3469 if (set_core_nodump_flag)
3470 vattr.va_flags = UF_NODUMP;
3471 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3472 VOP_SETATTR(vp, &vattr, cred);
3475 p->p_acflag |= ACORE;
3478 if (p->p_sysent->sv_coredump != NULL) {
3479 error = p->p_sysent->sv_coredump(td, vp, limit,
3480 compress_user_cores ? IMGACT_CORE_COMPRESS : 0);
3486 lf.l_type = F_UNLCK;
3487 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3489 vn_rangelock_unlock(vp, rl_cookie);
3492 * Notify the userland helper that a process triggered a core dump.
3493 * This allows the helper to run an automated debugging session.
3495 if (error != 0 || coredump_devctl == 0)
3497 len = MAXPATHLEN * 2 + sizeof(comm_name) - 1 +
3498 sizeof(' ') + sizeof(core_name) - 1;
3499 data = malloc(len, M_TEMP, M_WAITOK);
3500 if (vn_fullpath_global(td, p->p_textvp, &fullpath, &freepath) != 0)
3502 if (!coredump_sanitise_path(fullpath))
3504 snprintf(data, len, "%s%s ", comm_name, fullpath);
3505 free(freepath, M_TEMP);
3507 if (vn_fullpath_global(td, vp, &fullpath, &freepath) != 0)
3509 if (!coredump_sanitise_path(fullpath))
3511 strlcat(data, core_name, len);
3512 strlcat(data, fullpath, len);
3513 devctl_notify("kernel", "signal", "coredump", data);
3515 error1 = vn_close(vp, FWRITE, cred, td);
3519 audit_proc_coredump(td, name, error);
3521 free(freepath, M_TEMP);
3528 * Nonexistent system call-- signal process (may want to handle it). Flag
3529 * error in case process won't see signal immediately (blocked or ignored).
3531 #ifndef _SYS_SYSPROTO_H_
3538 nosys(struct thread *td, struct nosys_args *args)
3540 struct proc *p = td->td_proc;
3543 tdsignal(td, SIGSYS);
3549 * Send a SIGIO or SIGURG signal to a process or process group using stored
3550 * credentials rather than those of the current process.
3553 pgsigio(struct sigio **sigiop, int sig, int checkctty)
3556 struct sigio *sigio;
3558 ksiginfo_init(&ksi);
3559 ksi.ksi_signo = sig;
3560 ksi.ksi_code = SI_KERNEL;
3564 if (sigio == NULL) {
3568 if (sigio->sio_pgid > 0) {
3569 PROC_LOCK(sigio->sio_proc);
3570 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3571 kern_psignal(sigio->sio_proc, sig);
3572 PROC_UNLOCK(sigio->sio_proc);
3573 } else if (sigio->sio_pgid < 0) {
3576 PGRP_LOCK(sigio->sio_pgrp);
3577 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3579 if (p->p_state == PRS_NORMAL &&
3580 CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3581 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3582 kern_psignal(p, sig);
3585 PGRP_UNLOCK(sigio->sio_pgrp);
3591 filt_sigattach(struct knote *kn)
3593 struct proc *p = curproc;
3595 kn->kn_ptr.p_proc = p;
3596 kn->kn_flags |= EV_CLEAR; /* automatically set */
3598 knlist_add(p->p_klist, kn, 0);
3604 filt_sigdetach(struct knote *kn)
3606 struct proc *p = kn->kn_ptr.p_proc;
3608 knlist_remove(p->p_klist, kn, 0);
3612 * signal knotes are shared with proc knotes, so we apply a mask to
3613 * the hint in order to differentiate them from process hints. This
3614 * could be avoided by using a signal-specific knote list, but probably
3615 * isn't worth the trouble.
3618 filt_signal(struct knote *kn, long hint)
3621 if (hint & NOTE_SIGNAL) {
3622 hint &= ~NOTE_SIGNAL;
3624 if (kn->kn_id == hint)
3627 return (kn->kn_data != 0);
3635 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3636 refcount_init(&ps->ps_refcnt, 1);
3637 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3642 sigacts_free(struct sigacts *ps)
3645 if (refcount_release(&ps->ps_refcnt) == 0)
3647 mtx_destroy(&ps->ps_mtx);
3648 free(ps, M_SUBPROC);
3652 sigacts_hold(struct sigacts *ps)
3655 refcount_acquire(&ps->ps_refcnt);
3660 sigacts_copy(struct sigacts *dest, struct sigacts *src)
3663 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3664 mtx_lock(&src->ps_mtx);
3665 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3666 mtx_unlock(&src->ps_mtx);
3670 sigacts_shared(struct sigacts *ps)
3673 return (ps->ps_refcnt > 1);