39
40#include "opt_compat.h"
41#include "opt_kdtrace.h"
42#include "opt_ktrace.h"
43#include "opt_core.h"
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/signalvar.h>
48#include <sys/vnode.h>
49#include <sys/acct.h>
50#include <sys/condvar.h>
51#include <sys/event.h>
52#include <sys/fcntl.h>
53#include <sys/imgact.h>
54#include <sys/kernel.h>
55#include <sys/ktr.h>
56#include <sys/ktrace.h>
57#include <sys/lock.h>
58#include <sys/malloc.h>
59#include <sys/mutex.h>
60#include <sys/namei.h>
61#include <sys/proc.h>
62#include <sys/posix4.h>
63#include <sys/pioctl.h>
64#include <sys/resourcevar.h>
65#include <sys/sdt.h>
66#include <sys/sbuf.h>
67#include <sys/sleepqueue.h>
68#include <sys/smp.h>
69#include <sys/stat.h>
70#include <sys/sx.h>
71#include <sys/syscallsubr.h>
72#include <sys/sysctl.h>
73#include <sys/sysent.h>
74#include <sys/syslog.h>
75#include <sys/sysproto.h>
76#include <sys/timers.h>
77#include <sys/unistd.h>
78#include <sys/wait.h>
79#include <vm/vm.h>
80#include <vm/vm_extern.h>
81#include <vm/uma.h>
82
83#include <sys/jail.h>
84
85#include <machine/cpu.h>
86
87#include <security/audit/audit.h>
88
89#define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
90
91SDT_PROVIDER_DECLARE(proc);
92SDT_PROBE_DEFINE(proc, kernel, , signal_send);
93SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 0, "struct thread *");
94SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 1, "struct proc *");
95SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 2, "int");
96SDT_PROBE_DEFINE(proc, kernel, , signal_clear);
97SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 0, "int");
98SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 1, "ksiginfo_t *");
99SDT_PROBE_DEFINE(proc, kernel, , signal_discard);
100SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 0, "struct thread *");
101SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 1, "struct proc *");
102SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 2, "int");
103
104static int coredump(struct thread *);
105static char *expand_name(const char *, uid_t, pid_t, struct thread *, int);
106static int killpg1(struct thread *td, int sig, int pgid, int all,
107 ksiginfo_t *ksi);
108static int issignal(struct thread *td, int stop_allowed);
109static int sigprop(int sig);
110static int tdsendsignal(struct proc *p, struct thread *td, int sig,
111 ksiginfo_t *ksi);
112static void tdsigwakeup(struct thread *, int, sig_t, int);
113static void sig_suspend_threads(struct thread *, struct proc *, int);
114static int filt_sigattach(struct knote *kn);
115static void filt_sigdetach(struct knote *kn);
116static int filt_signal(struct knote *kn, long hint);
117static struct thread *sigtd(struct proc *p, int sig, int prop);
118static void sigqueue_start(void);
119
120static uma_zone_t ksiginfo_zone = NULL;
121struct filterops sig_filtops = {
122 .f_isfd = 0,
123 .f_attach = filt_sigattach,
124 .f_detach = filt_sigdetach,
125 .f_event = filt_signal,
126};
127
128int kern_logsigexit = 1;
129SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
130 &kern_logsigexit, 0,
131 "Log processes quitting on abnormal signals to syslog(3)");
132
133static int kern_forcesigexit = 1;
134SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
135 &kern_forcesigexit, 0, "Force trap signal to be handled");
136
137SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0, "POSIX real time signal");
138
139static int max_pending_per_proc = 128;
140SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
141 &max_pending_per_proc, 0, "Max pending signals per proc");
142
143static int preallocate_siginfo = 1024;
144TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
145SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
146 &preallocate_siginfo, 0, "Preallocated signal memory size");
147
148static int signal_overflow = 0;
149SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
150 &signal_overflow, 0, "Number of signals overflew");
151
152static int signal_alloc_fail = 0;
153SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
154 &signal_alloc_fail, 0, "signals failed to be allocated");
155
156SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
157
158/*
159 * Policy -- Can ucred cr1 send SIGIO to process cr2?
160 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
161 * in the right situations.
162 */
163#define CANSIGIO(cr1, cr2) \
164 ((cr1)->cr_uid == 0 || \
165 (cr1)->cr_ruid == (cr2)->cr_ruid || \
166 (cr1)->cr_uid == (cr2)->cr_ruid || \
167 (cr1)->cr_ruid == (cr2)->cr_uid || \
168 (cr1)->cr_uid == (cr2)->cr_uid)
169
170int sugid_coredump;
171SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
172 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
173
174static int do_coredump = 1;
175SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
176 &do_coredump, 0, "Enable/Disable coredumps");
177
178static int set_core_nodump_flag = 0;
179SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
180 0, "Enable setting the NODUMP flag on coredump files");
181
182/*
183 * Signal properties and actions.
184 * The array below categorizes the signals and their default actions
185 * according to the following properties:
186 */
187#define SA_KILL 0x01 /* terminates process by default */
188#define SA_CORE 0x02 /* ditto and coredumps */
189#define SA_STOP 0x04 /* suspend process */
190#define SA_TTYSTOP 0x08 /* ditto, from tty */
191#define SA_IGNORE 0x10 /* ignore by default */
192#define SA_CONT 0x20 /* continue if suspended */
193#define SA_CANTMASK 0x40 /* non-maskable, catchable */
194#define SA_PROC 0x80 /* deliverable to any thread */
195
196static int sigproptbl[NSIG] = {
197 SA_KILL|SA_PROC, /* SIGHUP */
198 SA_KILL|SA_PROC, /* SIGINT */
199 SA_KILL|SA_CORE|SA_PROC, /* SIGQUIT */
200 SA_KILL|SA_CORE, /* SIGILL */
201 SA_KILL|SA_CORE, /* SIGTRAP */
202 SA_KILL|SA_CORE, /* SIGABRT */
203 SA_KILL|SA_CORE|SA_PROC, /* SIGEMT */
204 SA_KILL|SA_CORE, /* SIGFPE */
205 SA_KILL|SA_PROC, /* SIGKILL */
206 SA_KILL|SA_CORE, /* SIGBUS */
207 SA_KILL|SA_CORE, /* SIGSEGV */
208 SA_KILL|SA_CORE, /* SIGSYS */
209 SA_KILL|SA_PROC, /* SIGPIPE */
210 SA_KILL|SA_PROC, /* SIGALRM */
211 SA_KILL|SA_PROC, /* SIGTERM */
212 SA_IGNORE|SA_PROC, /* SIGURG */
213 SA_STOP|SA_PROC, /* SIGSTOP */
214 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTSTP */
215 SA_IGNORE|SA_CONT|SA_PROC, /* SIGCONT */
216 SA_IGNORE|SA_PROC, /* SIGCHLD */
217 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTIN */
218 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTOU */
219 SA_IGNORE|SA_PROC, /* SIGIO */
220 SA_KILL, /* SIGXCPU */
221 SA_KILL, /* SIGXFSZ */
222 SA_KILL|SA_PROC, /* SIGVTALRM */
223 SA_KILL|SA_PROC, /* SIGPROF */
224 SA_IGNORE|SA_PROC, /* SIGWINCH */
225 SA_IGNORE|SA_PROC, /* SIGINFO */
226 SA_KILL|SA_PROC, /* SIGUSR1 */
227 SA_KILL|SA_PROC, /* SIGUSR2 */
228};
229
230static void reschedule_signals(struct proc *p, sigset_t block, int flags);
231
232static void
233sigqueue_start(void)
234{
235 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
236 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
237 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
238 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
239 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
240 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
241}
242
243ksiginfo_t *
244ksiginfo_alloc(int wait)
245{
246 int flags;
247
248 flags = M_ZERO;
249 if (! wait)
250 flags |= M_NOWAIT;
251 if (ksiginfo_zone != NULL)
252 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
253 return (NULL);
254}
255
256void
257ksiginfo_free(ksiginfo_t *ksi)
258{
259 uma_zfree(ksiginfo_zone, ksi);
260}
261
262static __inline int
263ksiginfo_tryfree(ksiginfo_t *ksi)
264{
265 if (!(ksi->ksi_flags & KSI_EXT)) {
266 uma_zfree(ksiginfo_zone, ksi);
267 return (1);
268 }
269 return (0);
270}
271
272void
273sigqueue_init(sigqueue_t *list, struct proc *p)
274{
275 SIGEMPTYSET(list->sq_signals);
276 SIGEMPTYSET(list->sq_kill);
277 TAILQ_INIT(&list->sq_list);
278 list->sq_proc = p;
279 list->sq_flags = SQ_INIT;
280}
281
282/*
283 * Get a signal's ksiginfo.
284 * Return:
285 * 0 - signal not found
286 * others - signal number
287 */
288static int
289sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
290{
291 struct proc *p = sq->sq_proc;
292 struct ksiginfo *ksi, *next;
293 int count = 0;
294
295 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
296
297 if (!SIGISMEMBER(sq->sq_signals, signo))
298 return (0);
299
300 if (SIGISMEMBER(sq->sq_kill, signo)) {
301 count++;
302 SIGDELSET(sq->sq_kill, signo);
303 }
304
305 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
306 if (ksi->ksi_signo == signo) {
307 if (count == 0) {
308 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
309 ksi->ksi_sigq = NULL;
310 ksiginfo_copy(ksi, si);
311 if (ksiginfo_tryfree(ksi) && p != NULL)
312 p->p_pendingcnt--;
313 }
314 if (++count > 1)
315 break;
316 }
317 }
318
319 if (count <= 1)
320 SIGDELSET(sq->sq_signals, signo);
321 si->ksi_signo = signo;
322 return (signo);
323}
324
325void
326sigqueue_take(ksiginfo_t *ksi)
327{
328 struct ksiginfo *kp;
329 struct proc *p;
330 sigqueue_t *sq;
331
332 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
333 return;
334
335 p = sq->sq_proc;
336 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
337 ksi->ksi_sigq = NULL;
338 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
339 p->p_pendingcnt--;
340
341 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
342 kp = TAILQ_NEXT(kp, ksi_link)) {
343 if (kp->ksi_signo == ksi->ksi_signo)
344 break;
345 }
346 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
347 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
348}
349
350static int
351sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
352{
353 struct proc *p = sq->sq_proc;
354 struct ksiginfo *ksi;
355 int ret = 0;
356
357 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
358
359 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
360 SIGADDSET(sq->sq_kill, signo);
361 goto out_set_bit;
362 }
363
364 /* directly insert the ksi, don't copy it */
365 if (si->ksi_flags & KSI_INS) {
366 if (si->ksi_flags & KSI_HEAD)
367 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
368 else
369 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
370 si->ksi_sigq = sq;
371 goto out_set_bit;
372 }
373
374 if (__predict_false(ksiginfo_zone == NULL)) {
375 SIGADDSET(sq->sq_kill, signo);
376 goto out_set_bit;
377 }
378
379 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
380 signal_overflow++;
381 ret = EAGAIN;
382 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
383 signal_alloc_fail++;
384 ret = EAGAIN;
385 } else {
386 if (p != NULL)
387 p->p_pendingcnt++;
388 ksiginfo_copy(si, ksi);
389 ksi->ksi_signo = signo;
390 if (si->ksi_flags & KSI_HEAD)
391 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
392 else
393 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
394 ksi->ksi_sigq = sq;
395 }
396
397 if ((si->ksi_flags & KSI_TRAP) != 0 ||
398 (si->ksi_flags & KSI_SIGQ) == 0) {
399 if (ret != 0)
400 SIGADDSET(sq->sq_kill, signo);
401 ret = 0;
402 goto out_set_bit;
403 }
404
405 if (ret != 0)
406 return (ret);
407
408out_set_bit:
409 SIGADDSET(sq->sq_signals, signo);
410 return (ret);
411}
412
413void
414sigqueue_flush(sigqueue_t *sq)
415{
416 struct proc *p = sq->sq_proc;
417 ksiginfo_t *ksi;
418
419 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
420
421 if (p != NULL)
422 PROC_LOCK_ASSERT(p, MA_OWNED);
423
424 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
425 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
426 ksi->ksi_sigq = NULL;
427 if (ksiginfo_tryfree(ksi) && p != NULL)
428 p->p_pendingcnt--;
429 }
430
431 SIGEMPTYSET(sq->sq_signals);
432 SIGEMPTYSET(sq->sq_kill);
433}
434
435static void
436sigqueue_collect_set(sigqueue_t *sq, sigset_t *set)
437{
438 ksiginfo_t *ksi;
439
440 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
441
442 TAILQ_FOREACH(ksi, &sq->sq_list, ksi_link)
443 SIGADDSET(*set, ksi->ksi_signo);
444 SIGSETOR(*set, sq->sq_kill);
445}
446
447static void
448sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, sigset_t *setp)
449{
450 sigset_t tmp, set;
451 struct proc *p1, *p2;
452 ksiginfo_t *ksi, *next;
453
454 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
455 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
456 /*
457 * make a copy, this allows setp to point to src or dst
458 * sq_signals without trouble.
459 */
460 set = *setp;
461 p1 = src->sq_proc;
462 p2 = dst->sq_proc;
463 /* Move siginfo to target list */
464 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
465 if (SIGISMEMBER(set, ksi->ksi_signo)) {
466 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
467 if (p1 != NULL)
468 p1->p_pendingcnt--;
469 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
470 ksi->ksi_sigq = dst;
471 if (p2 != NULL)
472 p2->p_pendingcnt++;
473 }
474 }
475
476 /* Move pending bits to target list */
477 tmp = src->sq_kill;
478 SIGSETAND(tmp, set);
479 SIGSETOR(dst->sq_kill, tmp);
480 SIGSETNAND(src->sq_kill, tmp);
481
482 tmp = src->sq_signals;
483 SIGSETAND(tmp, set);
484 SIGSETOR(dst->sq_signals, tmp);
485 SIGSETNAND(src->sq_signals, tmp);
486
487 /* Finally, rescan src queue and set pending bits for it */
488 sigqueue_collect_set(src, &src->sq_signals);
489}
490
491static void
492sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
493{
494 sigset_t set;
495
496 SIGEMPTYSET(set);
497 SIGADDSET(set, signo);
498 sigqueue_move_set(src, dst, &set);
499}
500
501static void
502sigqueue_delete_set(sigqueue_t *sq, sigset_t *set)
503{
504 struct proc *p = sq->sq_proc;
505 ksiginfo_t *ksi, *next;
506
507 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
508
509 /* Remove siginfo queue */
510 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
511 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
512 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
513 ksi->ksi_sigq = NULL;
514 if (ksiginfo_tryfree(ksi) && p != NULL)
515 p->p_pendingcnt--;
516 }
517 }
518 SIGSETNAND(sq->sq_kill, *set);
519 SIGSETNAND(sq->sq_signals, *set);
520 /* Finally, rescan queue and set pending bits for it */
521 sigqueue_collect_set(sq, &sq->sq_signals);
522}
523
524void
525sigqueue_delete(sigqueue_t *sq, int signo)
526{
527 sigset_t set;
528
529 SIGEMPTYSET(set);
530 SIGADDSET(set, signo);
531 sigqueue_delete_set(sq, &set);
532}
533
534/* Remove a set of signals for a process */
535static void
536sigqueue_delete_set_proc(struct proc *p, sigset_t *set)
537{
538 sigqueue_t worklist;
539 struct thread *td0;
540
541 PROC_LOCK_ASSERT(p, MA_OWNED);
542
543 sigqueue_init(&worklist, NULL);
544 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
545
546 FOREACH_THREAD_IN_PROC(p, td0)
547 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
548
549 sigqueue_flush(&worklist);
550}
551
552void
553sigqueue_delete_proc(struct proc *p, int signo)
554{
555 sigset_t set;
556
557 SIGEMPTYSET(set);
558 SIGADDSET(set, signo);
559 sigqueue_delete_set_proc(p, &set);
560}
561
562static void
563sigqueue_delete_stopmask_proc(struct proc *p)
564{
565 sigset_t set;
566
567 SIGEMPTYSET(set);
568 SIGADDSET(set, SIGSTOP);
569 SIGADDSET(set, SIGTSTP);
570 SIGADDSET(set, SIGTTIN);
571 SIGADDSET(set, SIGTTOU);
572 sigqueue_delete_set_proc(p, &set);
573}
574
575/*
576 * Determine signal that should be delivered to process p, the current
577 * process, 0 if none. If there is a pending stop signal with default
578 * action, the process stops in issignal().
579 */
580int
581cursig(struct thread *td, int stop_allowed)
582{
583 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
584 KASSERT(stop_allowed == SIG_STOP_ALLOWED ||
585 stop_allowed == SIG_STOP_NOT_ALLOWED, ("cursig: stop_allowed"));
586 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
587 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
588 return (SIGPENDING(td) ? issignal(td, stop_allowed) : 0);
589}
590
591/*
592 * Arrange for ast() to handle unmasked pending signals on return to user
593 * mode. This must be called whenever a signal is added to td_sigqueue or
594 * unmasked in td_sigmask.
595 */
596void
597signotify(struct thread *td)
598{
599 struct proc *p;
600
601 p = td->td_proc;
602
603 PROC_LOCK_ASSERT(p, MA_OWNED);
604
605 if (SIGPENDING(td)) {
606 thread_lock(td);
607 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
608 thread_unlock(td);
609 }
610}
611
612int
613sigonstack(size_t sp)
614{
615 struct thread *td = curthread;
616
617 return ((td->td_pflags & TDP_ALTSTACK) ?
618#if defined(COMPAT_43)
619 ((td->td_sigstk.ss_size == 0) ?
620 (td->td_sigstk.ss_flags & SS_ONSTACK) :
621 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
622#else
623 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
624#endif
625 : 0);
626}
627
628static __inline int
629sigprop(int sig)
630{
631
632 if (sig > 0 && sig < NSIG)
633 return (sigproptbl[_SIG_IDX(sig)]);
634 return (0);
635}
636
637int
638sig_ffs(sigset_t *set)
639{
640 int i;
641
642 for (i = 0; i < _SIG_WORDS; i++)
643 if (set->__bits[i])
644 return (ffs(set->__bits[i]) + (i * 32));
645 return (0);
646}
647
648/*
649 * kern_sigaction
650 * sigaction
651 * freebsd4_sigaction
652 * osigaction
653 */
654int
655kern_sigaction(td, sig, act, oact, flags)
656 struct thread *td;
657 register int sig;
658 struct sigaction *act, *oact;
659 int flags;
660{
661 struct sigacts *ps;
662 struct proc *p = td->td_proc;
663
664 if (!_SIG_VALID(sig))
665 return (EINVAL);
666
667 PROC_LOCK(p);
668 ps = p->p_sigacts;
669 mtx_lock(&ps->ps_mtx);
670 if (oact) {
671 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
672 oact->sa_flags = 0;
673 if (SIGISMEMBER(ps->ps_sigonstack, sig))
674 oact->sa_flags |= SA_ONSTACK;
675 if (!SIGISMEMBER(ps->ps_sigintr, sig))
676 oact->sa_flags |= SA_RESTART;
677 if (SIGISMEMBER(ps->ps_sigreset, sig))
678 oact->sa_flags |= SA_RESETHAND;
679 if (SIGISMEMBER(ps->ps_signodefer, sig))
680 oact->sa_flags |= SA_NODEFER;
681 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
682 oact->sa_flags |= SA_SIGINFO;
683 oact->sa_sigaction =
684 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
685 } else
686 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
687 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
688 oact->sa_flags |= SA_NOCLDSTOP;
689 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
690 oact->sa_flags |= SA_NOCLDWAIT;
691 }
692 if (act) {
693 if ((sig == SIGKILL || sig == SIGSTOP) &&
694 act->sa_handler != SIG_DFL) {
695 mtx_unlock(&ps->ps_mtx);
696 PROC_UNLOCK(p);
697 return (EINVAL);
698 }
699
700 /*
701 * Change setting atomically.
702 */
703
704 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
705 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
706 if (act->sa_flags & SA_SIGINFO) {
707 ps->ps_sigact[_SIG_IDX(sig)] =
708 (__sighandler_t *)act->sa_sigaction;
709 SIGADDSET(ps->ps_siginfo, sig);
710 } else {
711 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
712 SIGDELSET(ps->ps_siginfo, sig);
713 }
714 if (!(act->sa_flags & SA_RESTART))
715 SIGADDSET(ps->ps_sigintr, sig);
716 else
717 SIGDELSET(ps->ps_sigintr, sig);
718 if (act->sa_flags & SA_ONSTACK)
719 SIGADDSET(ps->ps_sigonstack, sig);
720 else
721 SIGDELSET(ps->ps_sigonstack, sig);
722 if (act->sa_flags & SA_RESETHAND)
723 SIGADDSET(ps->ps_sigreset, sig);
724 else
725 SIGDELSET(ps->ps_sigreset, sig);
726 if (act->sa_flags & SA_NODEFER)
727 SIGADDSET(ps->ps_signodefer, sig);
728 else
729 SIGDELSET(ps->ps_signodefer, sig);
730 if (sig == SIGCHLD) {
731 if (act->sa_flags & SA_NOCLDSTOP)
732 ps->ps_flag |= PS_NOCLDSTOP;
733 else
734 ps->ps_flag &= ~PS_NOCLDSTOP;
735 if (act->sa_flags & SA_NOCLDWAIT) {
736 /*
737 * Paranoia: since SA_NOCLDWAIT is implemented
738 * by reparenting the dying child to PID 1 (and
739 * trust it to reap the zombie), PID 1 itself
740 * is forbidden to set SA_NOCLDWAIT.
741 */
742 if (p->p_pid == 1)
743 ps->ps_flag &= ~PS_NOCLDWAIT;
744 else
745 ps->ps_flag |= PS_NOCLDWAIT;
746 } else
747 ps->ps_flag &= ~PS_NOCLDWAIT;
748 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
749 ps->ps_flag |= PS_CLDSIGIGN;
750 else
751 ps->ps_flag &= ~PS_CLDSIGIGN;
752 }
753 /*
754 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
755 * and for signals set to SIG_DFL where the default is to
756 * ignore. However, don't put SIGCONT in ps_sigignore, as we
757 * have to restart the process.
758 */
759 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
760 (sigprop(sig) & SA_IGNORE &&
761 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
762 /* never to be seen again */
763 sigqueue_delete_proc(p, sig);
764 if (sig != SIGCONT)
765 /* easier in psignal */
766 SIGADDSET(ps->ps_sigignore, sig);
767 SIGDELSET(ps->ps_sigcatch, sig);
768 } else {
769 SIGDELSET(ps->ps_sigignore, sig);
770 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
771 SIGDELSET(ps->ps_sigcatch, sig);
772 else
773 SIGADDSET(ps->ps_sigcatch, sig);
774 }
775#ifdef COMPAT_FREEBSD4
776 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
777 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
778 (flags & KSA_FREEBSD4) == 0)
779 SIGDELSET(ps->ps_freebsd4, sig);
780 else
781 SIGADDSET(ps->ps_freebsd4, sig);
782#endif
783#ifdef COMPAT_43
784 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
785 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
786 (flags & KSA_OSIGSET) == 0)
787 SIGDELSET(ps->ps_osigset, sig);
788 else
789 SIGADDSET(ps->ps_osigset, sig);
790#endif
791 }
792 mtx_unlock(&ps->ps_mtx);
793 PROC_UNLOCK(p);
794 return (0);
795}
796
797#ifndef _SYS_SYSPROTO_H_
798struct sigaction_args {
799 int sig;
800 struct sigaction *act;
801 struct sigaction *oact;
802};
803#endif
804int
805sigaction(td, uap)
806 struct thread *td;
807 register struct sigaction_args *uap;
808{
809 struct sigaction act, oact;
810 register struct sigaction *actp, *oactp;
811 int error;
812
813 actp = (uap->act != NULL) ? &act : NULL;
814 oactp = (uap->oact != NULL) ? &oact : NULL;
815 if (actp) {
816 error = copyin(uap->act, actp, sizeof(act));
817 if (error)
818 return (error);
819 }
820 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
821 if (oactp && !error)
822 error = copyout(oactp, uap->oact, sizeof(oact));
823 return (error);
824}
825
826#ifdef COMPAT_FREEBSD4
827#ifndef _SYS_SYSPROTO_H_
828struct freebsd4_sigaction_args {
829 int sig;
830 struct sigaction *act;
831 struct sigaction *oact;
832};
833#endif
834int
835freebsd4_sigaction(td, uap)
836 struct thread *td;
837 register struct freebsd4_sigaction_args *uap;
838{
839 struct sigaction act, oact;
840 register struct sigaction *actp, *oactp;
841 int error;
842
843
844 actp = (uap->act != NULL) ? &act : NULL;
845 oactp = (uap->oact != NULL) ? &oact : NULL;
846 if (actp) {
847 error = copyin(uap->act, actp, sizeof(act));
848 if (error)
849 return (error);
850 }
851 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
852 if (oactp && !error)
853 error = copyout(oactp, uap->oact, sizeof(oact));
854 return (error);
855}
856#endif /* COMAPT_FREEBSD4 */
857
858#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
859#ifndef _SYS_SYSPROTO_H_
860struct osigaction_args {
861 int signum;
862 struct osigaction *nsa;
863 struct osigaction *osa;
864};
865#endif
866int
867osigaction(td, uap)
868 struct thread *td;
869 register struct osigaction_args *uap;
870{
871 struct osigaction sa;
872 struct sigaction nsa, osa;
873 register struct sigaction *nsap, *osap;
874 int error;
875
876 if (uap->signum <= 0 || uap->signum >= ONSIG)
877 return (EINVAL);
878
879 nsap = (uap->nsa != NULL) ? &nsa : NULL;
880 osap = (uap->osa != NULL) ? &osa : NULL;
881
882 if (nsap) {
883 error = copyin(uap->nsa, &sa, sizeof(sa));
884 if (error)
885 return (error);
886 nsap->sa_handler = sa.sa_handler;
887 nsap->sa_flags = sa.sa_flags;
888 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
889 }
890 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
891 if (osap && !error) {
892 sa.sa_handler = osap->sa_handler;
893 sa.sa_flags = osap->sa_flags;
894 SIG2OSIG(osap->sa_mask, sa.sa_mask);
895 error = copyout(&sa, uap->osa, sizeof(sa));
896 }
897 return (error);
898}
899
900#if !defined(__i386__)
901/* Avoid replicating the same stub everywhere */
902int
903osigreturn(td, uap)
904 struct thread *td;
905 struct osigreturn_args *uap;
906{
907
908 return (nosys(td, (struct nosys_args *)uap));
909}
910#endif
911#endif /* COMPAT_43 */
912
913/*
914 * Initialize signal state for process 0;
915 * set to ignore signals that are ignored by default.
916 */
917void
918siginit(p)
919 struct proc *p;
920{
921 register int i;
922 struct sigacts *ps;
923
924 PROC_LOCK(p);
925 ps = p->p_sigacts;
926 mtx_lock(&ps->ps_mtx);
927 for (i = 1; i <= NSIG; i++)
928 if (sigprop(i) & SA_IGNORE && i != SIGCONT)
929 SIGADDSET(ps->ps_sigignore, i);
930 mtx_unlock(&ps->ps_mtx);
931 PROC_UNLOCK(p);
932}
933
934/*
935 * Reset signals for an exec of the specified process.
936 */
937void
938execsigs(struct proc *p)
939{
940 struct sigacts *ps;
941 int sig;
942 struct thread *td;
943
944 /*
945 * Reset caught signals. Held signals remain held
946 * through td_sigmask (unless they were caught,
947 * and are now ignored by default).
948 */
949 PROC_LOCK_ASSERT(p, MA_OWNED);
950 td = FIRST_THREAD_IN_PROC(p);
951 ps = p->p_sigacts;
952 mtx_lock(&ps->ps_mtx);
953 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
954 sig = sig_ffs(&ps->ps_sigcatch);
955 SIGDELSET(ps->ps_sigcatch, sig);
956 if (sigprop(sig) & SA_IGNORE) {
957 if (sig != SIGCONT)
958 SIGADDSET(ps->ps_sigignore, sig);
959 sigqueue_delete_proc(p, sig);
960 }
961 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
962 }
963 /*
964 * Reset stack state to the user stack.
965 * Clear set of signals caught on the signal stack.
966 */
967 td->td_sigstk.ss_flags = SS_DISABLE;
968 td->td_sigstk.ss_size = 0;
969 td->td_sigstk.ss_sp = 0;
970 td->td_pflags &= ~TDP_ALTSTACK;
971 /*
972 * Reset no zombies if child dies flag as Solaris does.
973 */
974 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
975 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
976 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
977 mtx_unlock(&ps->ps_mtx);
978}
979
980/*
981 * kern_sigprocmask()
982 *
983 * Manipulate signal mask.
984 */
985int
986kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
987 int flags)
988{
989 sigset_t new_block, oset1;
990 struct proc *p;
991 int error;
992
993 p = td->td_proc;
994 if (!(flags & SIGPROCMASK_PROC_LOCKED))
995 PROC_LOCK(p);
996 if (oset != NULL)
997 *oset = td->td_sigmask;
998
999 error = 0;
1000 SIGEMPTYSET(new_block);
1001 if (set != NULL) {
1002 switch (how) {
1003 case SIG_BLOCK:
1004 SIG_CANTMASK(*set);
1005 oset1 = td->td_sigmask;
1006 SIGSETOR(td->td_sigmask, *set);
1007 new_block = td->td_sigmask;
1008 SIGSETNAND(new_block, oset1);
1009 break;
1010 case SIG_UNBLOCK:
1011 SIGSETNAND(td->td_sigmask, *set);
1012 signotify(td);
1013 break;
1014 case SIG_SETMASK:
1015 SIG_CANTMASK(*set);
1016 oset1 = td->td_sigmask;
1017 if (flags & SIGPROCMASK_OLD)
1018 SIGSETLO(td->td_sigmask, *set);
1019 else
1020 td->td_sigmask = *set;
1021 new_block = td->td_sigmask;
1022 SIGSETNAND(new_block, oset1);
1023 signotify(td);
1024 break;
1025 default:
1026 error = EINVAL;
1027 break;
1028 }
1029 }
1030
1031 /*
1032 * The new_block set contains signals that were not previously
1033 * blocked, but are blocked now.
1034 *
1035 * In case we block any signal that was not previously blocked
1036 * for td, and process has the signal pending, try to schedule
1037 * signal delivery to some thread that does not block the signal,
1038 * possibly waking it up.
1039 */
1040 if (p->p_numthreads != 1)
1041 reschedule_signals(p, new_block, flags);
1042
1043 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1044 PROC_UNLOCK(p);
1045 return (error);
1046}
1047
1048#ifndef _SYS_SYSPROTO_H_
1049struct sigprocmask_args {
1050 int how;
1051 const sigset_t *set;
1052 sigset_t *oset;
1053};
1054#endif
1055int
1056sigprocmask(td, uap)
1057 register struct thread *td;
1058 struct sigprocmask_args *uap;
1059{
1060 sigset_t set, oset;
1061 sigset_t *setp, *osetp;
1062 int error;
1063
1064 setp = (uap->set != NULL) ? &set : NULL;
1065 osetp = (uap->oset != NULL) ? &oset : NULL;
1066 if (setp) {
1067 error = copyin(uap->set, setp, sizeof(set));
1068 if (error)
1069 return (error);
1070 }
1071 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1072 if (osetp && !error) {
1073 error = copyout(osetp, uap->oset, sizeof(oset));
1074 }
1075 return (error);
1076}
1077
1078#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1079#ifndef _SYS_SYSPROTO_H_
1080struct osigprocmask_args {
1081 int how;
1082 osigset_t mask;
1083};
1084#endif
1085int
1086osigprocmask(td, uap)
1087 register struct thread *td;
1088 struct osigprocmask_args *uap;
1089{
1090 sigset_t set, oset;
1091 int error;
1092
1093 OSIG2SIG(uap->mask, set);
1094 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1095 SIG2OSIG(oset, td->td_retval[0]);
1096 return (error);
1097}
1098#endif /* COMPAT_43 */
1099
1100int
1101sigwait(struct thread *td, struct sigwait_args *uap)
1102{
1103 ksiginfo_t ksi;
1104 sigset_t set;
1105 int error;
1106
1107 error = copyin(uap->set, &set, sizeof(set));
1108 if (error) {
1109 td->td_retval[0] = error;
1110 return (0);
1111 }
1112
1113 error = kern_sigtimedwait(td, set, &ksi, NULL);
1114 if (error) {
1115 if (error == ERESTART)
1116 return (error);
1117 td->td_retval[0] = error;
1118 return (0);
1119 }
1120
1121 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1122 td->td_retval[0] = error;
1123 return (0);
1124}
1125
1126int
1127sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1128{
1129 struct timespec ts;
1130 struct timespec *timeout;
1131 sigset_t set;
1132 ksiginfo_t ksi;
1133 int error;
1134
1135 if (uap->timeout) {
1136 error = copyin(uap->timeout, &ts, sizeof(ts));
1137 if (error)
1138 return (error);
1139
1140 timeout = &ts;
1141 } else
1142 timeout = NULL;
1143
1144 error = copyin(uap->set, &set, sizeof(set));
1145 if (error)
1146 return (error);
1147
1148 error = kern_sigtimedwait(td, set, &ksi, timeout);
1149 if (error)
1150 return (error);
1151
1152 if (uap->info)
1153 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1154
1155 if (error == 0)
1156 td->td_retval[0] = ksi.ksi_signo;
1157 return (error);
1158}
1159
1160int
1161sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1162{
1163 ksiginfo_t ksi;
1164 sigset_t set;
1165 int error;
1166
1167 error = copyin(uap->set, &set, sizeof(set));
1168 if (error)
1169 return (error);
1170
1171 error = kern_sigtimedwait(td, set, &ksi, NULL);
1172 if (error)
1173 return (error);
1174
1175 if (uap->info)
1176 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1177
1178 if (error == 0)
1179 td->td_retval[0] = ksi.ksi_signo;
1180 return (error);
1181}
1182
1183int
1184kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1185 struct timespec *timeout)
1186{
1187 struct sigacts *ps;
1188 sigset_t savedmask;
1189 struct proc *p;
1190 int error, sig, hz, i, timevalid = 0;
1191 struct timespec rts, ets, ts;
1192 struct timeval tv;
1193
1194 p = td->td_proc;
1195 error = 0;
1196 sig = 0;
1197 ets.tv_sec = 0;
1198 ets.tv_nsec = 0;
1199 SIG_CANTMASK(waitset);
1200
1201 PROC_LOCK(p);
1202 ps = p->p_sigacts;
1203 savedmask = td->td_sigmask;
1204 if (timeout) {
1205 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1206 timevalid = 1;
1207 getnanouptime(&rts);
1208 ets = rts;
1209 timespecadd(&ets, timeout);
1210 }
1211 }
1212
1213restart:
1214 for (i = 1; i <= _SIG_MAXSIG; ++i) {
1215 if (!SIGISMEMBER(waitset, i))
1216 continue;
1217 if (!SIGISMEMBER(td->td_sigqueue.sq_signals, i)) {
1218 if (SIGISMEMBER(p->p_sigqueue.sq_signals, i)) {
1219 sigqueue_move(&p->p_sigqueue,
1220 &td->td_sigqueue, i);
1221 } else
1222 continue;
1223 }
1224
1225 SIGFILLSET(td->td_sigmask);
1226 SIG_CANTMASK(td->td_sigmask);
1227 SIGDELSET(td->td_sigmask, i);
1228 mtx_lock(&ps->ps_mtx);
1229 sig = cursig(td, SIG_STOP_ALLOWED);
1230 mtx_unlock(&ps->ps_mtx);
1231 if (sig)
1232 goto out;
1233 else {
1234 /*
1235 * Because cursig() may have stopped current thread,
1236 * after it is resumed, things may have already been
1237 * changed, it should rescan any pending signals.
1238 */
1239 goto restart;
1240 }
1241 }
1242
1243 if (error)
1244 goto out;
1245
1246 /*
1247 * POSIX says this must be checked after looking for pending
1248 * signals.
1249 */
1250 if (timeout) {
1251 if (!timevalid) {
1252 error = EINVAL;
1253 goto out;
1254 }
1255 getnanouptime(&rts);
1256 if (timespeccmp(&rts, &ets, >=)) {
1257 error = EAGAIN;
1258 goto out;
1259 }
1260 ts = ets;
1261 timespecsub(&ts, &rts);
1262 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1263 hz = tvtohz(&tv);
1264 } else
1265 hz = 0;
1266
1267 td->td_sigmask = savedmask;
1268 SIGSETNAND(td->td_sigmask, waitset);
1269 signotify(td);
1270 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz);
1271 if (timeout) {
1272 if (error == ERESTART) {
1273 /* timeout can not be restarted. */
1274 error = EINTR;
1275 } else if (error == EAGAIN) {
1276 /* will calculate timeout by ourself. */
1277 error = 0;
1278 }
1279 }
1280 goto restart;
1281
1282out:
1283 td->td_sigmask = savedmask;
1284 signotify(td);
1285 if (sig) {
1286 ksiginfo_init(ksi);
1287 sigqueue_get(&td->td_sigqueue, sig, ksi);
1288 ksi->ksi_signo = sig;
1289
1290 SDT_PROBE(proc, kernel, , signal_clear, sig, ksi, 0, 0, 0);
1291
1292 if (ksi->ksi_code == SI_TIMER)
1293 itimer_accept(p, ksi->ksi_timerid, ksi);
1294 error = 0;
1295
1296#ifdef KTRACE
1297 if (KTRPOINT(td, KTR_PSIG)) {
1298 sig_t action;
1299
1300 mtx_lock(&ps->ps_mtx);
1301 action = ps->ps_sigact[_SIG_IDX(sig)];
1302 mtx_unlock(&ps->ps_mtx);
1303 ktrpsig(sig, action, &td->td_sigmask, 0);
1304 }
1305#endif
1306 if (sig == SIGKILL)
1307 sigexit(td, sig);
1308 }
1309 PROC_UNLOCK(p);
1310 return (error);
1311}
1312
1313#ifndef _SYS_SYSPROTO_H_
1314struct sigpending_args {
1315 sigset_t *set;
1316};
1317#endif
1318int
1319sigpending(td, uap)
1320 struct thread *td;
1321 struct sigpending_args *uap;
1322{
1323 struct proc *p = td->td_proc;
1324 sigset_t pending;
1325
1326 PROC_LOCK(p);
1327 pending = p->p_sigqueue.sq_signals;
1328 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1329 PROC_UNLOCK(p);
1330 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1331}
1332
1333#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1334#ifndef _SYS_SYSPROTO_H_
1335struct osigpending_args {
1336 int dummy;
1337};
1338#endif
1339int
1340osigpending(td, uap)
1341 struct thread *td;
1342 struct osigpending_args *uap;
1343{
1344 struct proc *p = td->td_proc;
1345 sigset_t pending;
1346
1347 PROC_LOCK(p);
1348 pending = p->p_sigqueue.sq_signals;
1349 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1350 PROC_UNLOCK(p);
1351 SIG2OSIG(pending, td->td_retval[0]);
1352 return (0);
1353}
1354#endif /* COMPAT_43 */
1355
1356#if defined(COMPAT_43)
1357/*
1358 * Generalized interface signal handler, 4.3-compatible.
1359 */
1360#ifndef _SYS_SYSPROTO_H_
1361struct osigvec_args {
1362 int signum;
1363 struct sigvec *nsv;
1364 struct sigvec *osv;
1365};
1366#endif
1367/* ARGSUSED */
1368int
1369osigvec(td, uap)
1370 struct thread *td;
1371 register struct osigvec_args *uap;
1372{
1373 struct sigvec vec;
1374 struct sigaction nsa, osa;
1375 register struct sigaction *nsap, *osap;
1376 int error;
1377
1378 if (uap->signum <= 0 || uap->signum >= ONSIG)
1379 return (EINVAL);
1380 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1381 osap = (uap->osv != NULL) ? &osa : NULL;
1382 if (nsap) {
1383 error = copyin(uap->nsv, &vec, sizeof(vec));
1384 if (error)
1385 return (error);
1386 nsap->sa_handler = vec.sv_handler;
1387 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1388 nsap->sa_flags = vec.sv_flags;
1389 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1390 }
1391 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1392 if (osap && !error) {
1393 vec.sv_handler = osap->sa_handler;
1394 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1395 vec.sv_flags = osap->sa_flags;
1396 vec.sv_flags &= ~SA_NOCLDWAIT;
1397 vec.sv_flags ^= SA_RESTART;
1398 error = copyout(&vec, uap->osv, sizeof(vec));
1399 }
1400 return (error);
1401}
1402
1403#ifndef _SYS_SYSPROTO_H_
1404struct osigblock_args {
1405 int mask;
1406};
1407#endif
1408int
1409osigblock(td, uap)
1410 register struct thread *td;
1411 struct osigblock_args *uap;
1412{
1413 sigset_t set, oset;
1414
1415 OSIG2SIG(uap->mask, set);
1416 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1417 SIG2OSIG(oset, td->td_retval[0]);
1418 return (0);
1419}
1420
1421#ifndef _SYS_SYSPROTO_H_
1422struct osigsetmask_args {
1423 int mask;
1424};
1425#endif
1426int
1427osigsetmask(td, uap)
1428 struct thread *td;
1429 struct osigsetmask_args *uap;
1430{
1431 sigset_t set, oset;
1432
1433 OSIG2SIG(uap->mask, set);
1434 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1435 SIG2OSIG(oset, td->td_retval[0]);
1436 return (0);
1437}
1438#endif /* COMPAT_43 */
1439
1440/*
1441 * Suspend calling thread until signal, providing mask to be set in the
1442 * meantime.
1443 */
1444#ifndef _SYS_SYSPROTO_H_
1445struct sigsuspend_args {
1446 const sigset_t *sigmask;
1447};
1448#endif
1449/* ARGSUSED */
1450int
1451sigsuspend(td, uap)
1452 struct thread *td;
1453 struct sigsuspend_args *uap;
1454{
1455 sigset_t mask;
1456 int error;
1457
1458 error = copyin(uap->sigmask, &mask, sizeof(mask));
1459 if (error)
1460 return (error);
1461 return (kern_sigsuspend(td, mask));
1462}
1463
1464int
1465kern_sigsuspend(struct thread *td, sigset_t mask)
1466{
1467 struct proc *p = td->td_proc;
1468 int has_sig, sig;
1469
1470 /*
1471 * When returning from sigsuspend, we want
1472 * the old mask to be restored after the
1473 * signal handler has finished. Thus, we
1474 * save it here and mark the sigacts structure
1475 * to indicate this.
1476 */
1477 PROC_LOCK(p);
1478 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1479 SIGPROCMASK_PROC_LOCKED);
1480 td->td_pflags |= TDP_OLDMASK;
1481
1482 /*
1483 * Process signals now. Otherwise, we can get spurious wakeup
1484 * due to signal entered process queue, but delivered to other
1485 * thread. But sigsuspend should return only on signal
1486 * delivery.
1487 */
1488 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1489 for (has_sig = 0; !has_sig;) {
1490 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1491 0) == 0)
1492 /* void */;
1493 thread_suspend_check(0);
1494 mtx_lock(&p->p_sigacts->ps_mtx);
1495 while ((sig = cursig(td, SIG_STOP_ALLOWED)) != 0)
1496 has_sig += postsig(sig);
1497 mtx_unlock(&p->p_sigacts->ps_mtx);
1498 }
1499 PROC_UNLOCK(p);
1500 return (EJUSTRETURN);
1501}
1502
1503#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1504/*
1505 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1506 * convention: libc stub passes mask, not pointer, to save a copyin.
1507 */
1508#ifndef _SYS_SYSPROTO_H_
1509struct osigsuspend_args {
1510 osigset_t mask;
1511};
1512#endif
1513/* ARGSUSED */
1514int
1515osigsuspend(td, uap)
1516 struct thread *td;
1517 struct osigsuspend_args *uap;
1518{
1519 sigset_t mask;
1520
1521 OSIG2SIG(uap->mask, mask);
1522 return (kern_sigsuspend(td, mask));
1523}
1524#endif /* COMPAT_43 */
1525
1526#if defined(COMPAT_43)
1527#ifndef _SYS_SYSPROTO_H_
1528struct osigstack_args {
1529 struct sigstack *nss;
1530 struct sigstack *oss;
1531};
1532#endif
1533/* ARGSUSED */
1534int
1535osigstack(td, uap)
1536 struct thread *td;
1537 register struct osigstack_args *uap;
1538{
1539 struct sigstack nss, oss;
1540 int error = 0;
1541
1542 if (uap->nss != NULL) {
1543 error = copyin(uap->nss, &nss, sizeof(nss));
1544 if (error)
1545 return (error);
1546 }
1547 oss.ss_sp = td->td_sigstk.ss_sp;
1548 oss.ss_onstack = sigonstack(cpu_getstack(td));
1549 if (uap->nss != NULL) {
1550 td->td_sigstk.ss_sp = nss.ss_sp;
1551 td->td_sigstk.ss_size = 0;
1552 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1553 td->td_pflags |= TDP_ALTSTACK;
1554 }
1555 if (uap->oss != NULL)
1556 error = copyout(&oss, uap->oss, sizeof(oss));
1557
1558 return (error);
1559}
1560#endif /* COMPAT_43 */
1561
1562#ifndef _SYS_SYSPROTO_H_
1563struct sigaltstack_args {
1564 stack_t *ss;
1565 stack_t *oss;
1566};
1567#endif
1568/* ARGSUSED */
1569int
1570sigaltstack(td, uap)
1571 struct thread *td;
1572 register struct sigaltstack_args *uap;
1573{
1574 stack_t ss, oss;
1575 int error;
1576
1577 if (uap->ss != NULL) {
1578 error = copyin(uap->ss, &ss, sizeof(ss));
1579 if (error)
1580 return (error);
1581 }
1582 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1583 (uap->oss != NULL) ? &oss : NULL);
1584 if (error)
1585 return (error);
1586 if (uap->oss != NULL)
1587 error = copyout(&oss, uap->oss, sizeof(stack_t));
1588 return (error);
1589}
1590
1591int
1592kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1593{
1594 struct proc *p = td->td_proc;
1595 int oonstack;
1596
1597 oonstack = sigonstack(cpu_getstack(td));
1598
1599 if (oss != NULL) {
1600 *oss = td->td_sigstk;
1601 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1602 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1603 }
1604
1605 if (ss != NULL) {
1606 if (oonstack)
1607 return (EPERM);
1608 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1609 return (EINVAL);
1610 if (!(ss->ss_flags & SS_DISABLE)) {
1611 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1612 return (ENOMEM);
1613
1614 td->td_sigstk = *ss;
1615 td->td_pflags |= TDP_ALTSTACK;
1616 } else {
1617 td->td_pflags &= ~TDP_ALTSTACK;
1618 }
1619 }
1620 return (0);
1621}
1622
1623/*
1624 * Common code for kill process group/broadcast kill.
1625 * cp is calling process.
1626 */
1627static int
1628killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1629{
1630 struct proc *p;
1631 struct pgrp *pgrp;
1632 int nfound = 0;
1633
1634 if (all) {
1635 /*
1636 * broadcast
1637 */
1638 sx_slock(&allproc_lock);
1639 FOREACH_PROC_IN_SYSTEM(p) {
1640 PROC_LOCK(p);
1641 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1642 p == td->td_proc || p->p_state == PRS_NEW) {
1643 PROC_UNLOCK(p);
1644 continue;
1645 }
1646 if (p_cansignal(td, p, sig) == 0) {
1647 nfound++;
1648 if (sig)
1649 pksignal(p, sig, ksi);
1650 }
1651 PROC_UNLOCK(p);
1652 }
1653 sx_sunlock(&allproc_lock);
1654 } else {
1655 sx_slock(&proctree_lock);
1656 if (pgid == 0) {
1657 /*
1658 * zero pgid means send to my process group.
1659 */
1660 pgrp = td->td_proc->p_pgrp;
1661 PGRP_LOCK(pgrp);
1662 } else {
1663 pgrp = pgfind(pgid);
1664 if (pgrp == NULL) {
1665 sx_sunlock(&proctree_lock);
1666 return (ESRCH);
1667 }
1668 }
1669 sx_sunlock(&proctree_lock);
1670 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1671 PROC_LOCK(p);
1672 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1673 p->p_state == PRS_NEW ) {
1674 PROC_UNLOCK(p);
1675 continue;
1676 }
1677 if (p_cansignal(td, p, sig) == 0) {
1678 nfound++;
1679 if (sig)
1680 pksignal(p, sig, ksi);
1681 }
1682 PROC_UNLOCK(p);
1683 }
1684 PGRP_UNLOCK(pgrp);
1685 }
1686 return (nfound ? 0 : ESRCH);
1687}
1688
1689#ifndef _SYS_SYSPROTO_H_
1690struct kill_args {
1691 int pid;
1692 int signum;
1693};
1694#endif
1695/* ARGSUSED */
1696int
1697kill(struct thread *td, struct kill_args *uap)
1698{
1699 ksiginfo_t ksi;
1700 struct proc *p;
1701 int error;
1702
1703 AUDIT_ARG_SIGNUM(uap->signum);
1704 AUDIT_ARG_PID(uap->pid);
1705 if ((u_int)uap->signum > _SIG_MAXSIG)
1706 return (EINVAL);
1707
1708 ksiginfo_init(&ksi);
1709 ksi.ksi_signo = uap->signum;
1710 ksi.ksi_code = SI_USER;
1711 ksi.ksi_pid = td->td_proc->p_pid;
1712 ksi.ksi_uid = td->td_ucred->cr_ruid;
1713
1714 if (uap->pid > 0) {
1715 /* kill single process */
1716 if ((p = pfind(uap->pid)) == NULL) {
1717 if ((p = zpfind(uap->pid)) == NULL)
1718 return (ESRCH);
1719 }
1720 AUDIT_ARG_PROCESS(p);
1721 error = p_cansignal(td, p, uap->signum);
1722 if (error == 0 && uap->signum)
1723 pksignal(p, uap->signum, &ksi);
1724 PROC_UNLOCK(p);
1725 return (error);
1726 }
1727 switch (uap->pid) {
1728 case -1: /* broadcast signal */
1729 return (killpg1(td, uap->signum, 0, 1, &ksi));
1730 case 0: /* signal own process group */
1731 return (killpg1(td, uap->signum, 0, 0, &ksi));
1732 default: /* negative explicit process group */
1733 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1734 }
1735 /* NOTREACHED */
1736}
1737
1738#if defined(COMPAT_43)
1739#ifndef _SYS_SYSPROTO_H_
1740struct okillpg_args {
1741 int pgid;
1742 int signum;
1743};
1744#endif
1745/* ARGSUSED */
1746int
1747okillpg(struct thread *td, struct okillpg_args *uap)
1748{
1749 ksiginfo_t ksi;
1750
1751 AUDIT_ARG_SIGNUM(uap->signum);
1752 AUDIT_ARG_PID(uap->pgid);
1753 if ((u_int)uap->signum > _SIG_MAXSIG)
1754 return (EINVAL);
1755
1756 ksiginfo_init(&ksi);
1757 ksi.ksi_signo = uap->signum;
1758 ksi.ksi_code = SI_USER;
1759 ksi.ksi_pid = td->td_proc->p_pid;
1760 ksi.ksi_uid = td->td_ucred->cr_ruid;
1761 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1762}
1763#endif /* COMPAT_43 */
1764
1765#ifndef _SYS_SYSPROTO_H_
1766struct sigqueue_args {
1767 pid_t pid;
1768 int signum;
1769 /* union sigval */ void *value;
1770};
1771#endif
1772int
1773sigqueue(struct thread *td, struct sigqueue_args *uap)
1774{
1775 ksiginfo_t ksi;
1776 struct proc *p;
1777 int error;
1778
1779 if ((u_int)uap->signum > _SIG_MAXSIG)
1780 return (EINVAL);
1781
1782 /*
1783 * Specification says sigqueue can only send signal to
1784 * single process.
1785 */
1786 if (uap->pid <= 0)
1787 return (EINVAL);
1788
1789 if ((p = pfind(uap->pid)) == NULL) {
1790 if ((p = zpfind(uap->pid)) == NULL)
1791 return (ESRCH);
1792 }
1793 error = p_cansignal(td, p, uap->signum);
1794 if (error == 0 && uap->signum != 0) {
1795 ksiginfo_init(&ksi);
1796 ksi.ksi_flags = KSI_SIGQ;
1797 ksi.ksi_signo = uap->signum;
1798 ksi.ksi_code = SI_QUEUE;
1799 ksi.ksi_pid = td->td_proc->p_pid;
1800 ksi.ksi_uid = td->td_ucred->cr_ruid;
1801 ksi.ksi_value.sival_ptr = uap->value;
1802 error = pksignal(p, ksi.ksi_signo, &ksi);
1803 }
1804 PROC_UNLOCK(p);
1805 return (error);
1806}
1807
1808/*
1809 * Send a signal to a process group.
1810 */
1811void
1812gsignal(int pgid, int sig, ksiginfo_t *ksi)
1813{
1814 struct pgrp *pgrp;
1815
1816 if (pgid != 0) {
1817 sx_slock(&proctree_lock);
1818 pgrp = pgfind(pgid);
1819 sx_sunlock(&proctree_lock);
1820 if (pgrp != NULL) {
1821 pgsignal(pgrp, sig, 0, ksi);
1822 PGRP_UNLOCK(pgrp);
1823 }
1824 }
1825}
1826
1827/*
1828 * Send a signal to a process group. If checktty is 1,
1829 * limit to members which have a controlling terminal.
1830 */
1831void
1832pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1833{
1834 struct proc *p;
1835
1836 if (pgrp) {
1837 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1838 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1839 PROC_LOCK(p);
1840 if (checkctty == 0 || p->p_flag & P_CONTROLT)
1841 pksignal(p, sig, ksi);
1842 PROC_UNLOCK(p);
1843 }
1844 }
1845}
1846
1847/*
1848 * Send a signal caused by a trap to the current thread. If it will be
1849 * caught immediately, deliver it with correct code. Otherwise, post it
1850 * normally.
1851 */
1852void
1853trapsignal(struct thread *td, ksiginfo_t *ksi)
1854{
1855 struct sigacts *ps;
1856 sigset_t mask;
1857 struct proc *p;
1858 int sig;
1859 int code;
1860
1861 p = td->td_proc;
1862 sig = ksi->ksi_signo;
1863 code = ksi->ksi_code;
1864 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1865
1866 PROC_LOCK(p);
1867 ps = p->p_sigacts;
1868 mtx_lock(&ps->ps_mtx);
1869 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1870 !SIGISMEMBER(td->td_sigmask, sig)) {
1871 td->td_ru.ru_nsignals++;
1872#ifdef KTRACE
1873 if (KTRPOINT(curthread, KTR_PSIG))
1874 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1875 &td->td_sigmask, code);
1876#endif
1877 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1878 ksi, &td->td_sigmask);
1879 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1880 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1881 SIGADDSET(mask, sig);
1882 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1883 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1884 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1885 /*
1886 * See kern_sigaction() for origin of this code.
1887 */
1888 SIGDELSET(ps->ps_sigcatch, sig);
1889 if (sig != SIGCONT &&
1890 sigprop(sig) & SA_IGNORE)
1891 SIGADDSET(ps->ps_sigignore, sig);
1892 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1893 }
1894 mtx_unlock(&ps->ps_mtx);
1895 } else {
1896 /*
1897 * Avoid a possible infinite loop if the thread
1898 * masking the signal or process is ignoring the
1899 * signal.
1900 */
1901 if (kern_forcesigexit &&
1902 (SIGISMEMBER(td->td_sigmask, sig) ||
1903 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1904 SIGDELSET(td->td_sigmask, sig);
1905 SIGDELSET(ps->ps_sigcatch, sig);
1906 SIGDELSET(ps->ps_sigignore, sig);
1907 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1908 }
1909 mtx_unlock(&ps->ps_mtx);
1910 p->p_code = code; /* XXX for core dump/debugger */
1911 p->p_sig = sig; /* XXX to verify code */
1912 tdsendsignal(p, td, sig, ksi);
1913 }
1914 PROC_UNLOCK(p);
1915}
1916
1917static struct thread *
1918sigtd(struct proc *p, int sig, int prop)
1919{
1920 struct thread *td, *signal_td;
1921
1922 PROC_LOCK_ASSERT(p, MA_OWNED);
1923
1924 /*
1925 * Check if current thread can handle the signal without
1926 * switching context to another thread.
1927 */
1928 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1929 return (curthread);
1930 signal_td = NULL;
1931 FOREACH_THREAD_IN_PROC(p, td) {
1932 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1933 signal_td = td;
1934 break;
1935 }
1936 }
1937 if (signal_td == NULL)
1938 signal_td = FIRST_THREAD_IN_PROC(p);
1939 return (signal_td);
1940}
1941
1942/*
1943 * Send the signal to the process. If the signal has an action, the action
1944 * is usually performed by the target process rather than the caller; we add
1945 * the signal to the set of pending signals for the process.
1946 *
1947 * Exceptions:
1948 * o When a stop signal is sent to a sleeping process that takes the
1949 * default action, the process is stopped without awakening it.
1950 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1951 * regardless of the signal action (eg, blocked or ignored).
1952 *
1953 * Other ignored signals are discarded immediately.
1954 *
1955 * NB: This function may be entered from the debugger via the "kill" DDB
1956 * command. There is little that can be done to mitigate the possibly messy
1957 * side effects of this unwise possibility.
1958 */
1959void
1960psignal(struct proc *p, int sig)
1961{
1962 ksiginfo_t ksi;
1963
1964 ksiginfo_init(&ksi);
1965 ksi.ksi_signo = sig;
1966 ksi.ksi_code = SI_KERNEL;
1967 (void) tdsendsignal(p, NULL, sig, &ksi);
1968}
1969
1970int
1971pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
1972{
1973
1974 return (tdsendsignal(p, NULL, sig, ksi));
1975}
1976
1977int
1978psignal_event(struct proc *p, struct sigevent *sigev, ksiginfo_t *ksi)
1979{
1980 struct thread *td = NULL;
1981
1982 PROC_LOCK_ASSERT(p, MA_OWNED);
1983
1984 KASSERT(!KSI_ONQ(ksi), ("psignal_event: ksi on queue"));
1985
1986 /*
1987 * ksi_code and other fields should be set before
1988 * calling this function.
1989 */
1990 ksi->ksi_signo = sigev->sigev_signo;
1991 ksi->ksi_value = sigev->sigev_value;
1992 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
1993 td = thread_find(p, sigev->sigev_notify_thread_id);
1994 if (td == NULL)
1995 return (ESRCH);
1996 }
1997 return (tdsendsignal(p, td, ksi->ksi_signo, ksi));
1998}
1999
2000void
2001tdsignal(struct thread *td, int sig)
2002{
2003 ksiginfo_t ksi;
2004
2005 ksiginfo_init(&ksi);
2006 ksi.ksi_signo = sig;
2007 ksi.ksi_code = SI_KERNEL;
2008 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2009}
2010
2011void
2012tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2013{
2014
2015 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2016}
2017
2018static int
2019tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2020{
2021 sig_t action;
2022 sigqueue_t *sigqueue;
2023 int prop;
2024 struct sigacts *ps;
2025 int intrval;
2026 int ret = 0;
2027 int wakeup_swapper;
2028
2029 PROC_LOCK_ASSERT(p, MA_OWNED);
2030
2031 if (!_SIG_VALID(sig))
2032 panic("tdsignal(): invalid signal %d", sig);
2033
2034 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("tdsignal: ksi on queue"));
2035
2036 /*
2037 * IEEE Std 1003.1-2001: return success when killing a zombie.
2038 */
2039 if (p->p_state == PRS_ZOMBIE) {
2040 if (ksi && (ksi->ksi_flags & KSI_INS))
2041 ksiginfo_tryfree(ksi);
2042 return (ret);
2043 }
2044
2045 ps = p->p_sigacts;
2046 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2047 prop = sigprop(sig);
2048
2049 if (td == NULL) {
2050 td = sigtd(p, sig, prop);
2051 sigqueue = &p->p_sigqueue;
2052 } else {
2053 KASSERT(td->td_proc == p, ("invalid thread"));
2054 sigqueue = &td->td_sigqueue;
2055 }
2056
2057 SDT_PROBE(proc, kernel, , signal_send, td, p, sig, 0, 0 );
2058
2059 /*
2060 * If the signal is being ignored,
2061 * then we forget about it immediately.
2062 * (Note: we don't set SIGCONT in ps_sigignore,
2063 * and if it is set to SIG_IGN,
2064 * action will be SIG_DFL here.)
2065 */
2066 mtx_lock(&ps->ps_mtx);
2067 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2068 SDT_PROBE(proc, kernel, , signal_discard, ps, td, sig, 0, 0 );
2069
2070 mtx_unlock(&ps->ps_mtx);
2071 if (ksi && (ksi->ksi_flags & KSI_INS))
2072 ksiginfo_tryfree(ksi);
2073 return (ret);
2074 }
2075 if (SIGISMEMBER(td->td_sigmask, sig))
2076 action = SIG_HOLD;
2077 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2078 action = SIG_CATCH;
2079 else
2080 action = SIG_DFL;
2081 if (SIGISMEMBER(ps->ps_sigintr, sig))
2082 intrval = EINTR;
2083 else
2084 intrval = ERESTART;
2085 mtx_unlock(&ps->ps_mtx);
2086
2087 if (prop & SA_CONT)
2088 sigqueue_delete_stopmask_proc(p);
2089 else if (prop & SA_STOP) {
2090 /*
2091 * If sending a tty stop signal to a member of an orphaned
2092 * process group, discard the signal here if the action
2093 * is default; don't stop the process below if sleeping,
2094 * and don't clear any pending SIGCONT.
2095 */
2096 if ((prop & SA_TTYSTOP) &&
2097 (p->p_pgrp->pg_jobc == 0) &&
2098 (action == SIG_DFL)) {
2099 if (ksi && (ksi->ksi_flags & KSI_INS))
2100 ksiginfo_tryfree(ksi);
2101 return (ret);
2102 }
2103 sigqueue_delete_proc(p, SIGCONT);
2104 if (p->p_flag & P_CONTINUED) {
2105 p->p_flag &= ~P_CONTINUED;
2106 PROC_LOCK(p->p_pptr);
2107 sigqueue_take(p->p_ksi);
2108 PROC_UNLOCK(p->p_pptr);
2109 }
2110 }
2111
2112 ret = sigqueue_add(sigqueue, sig, ksi);
2113 if (ret != 0)
2114 return (ret);
2115 signotify(td);
2116 /*
2117 * Defer further processing for signals which are held,
2118 * except that stopped processes must be continued by SIGCONT.
2119 */
2120 if (action == SIG_HOLD &&
2121 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2122 return (ret);
2123 /*
2124 * SIGKILL: Remove procfs STOPEVENTs.
2125 */
2126 if (sig == SIGKILL) {
2127 /* from procfs_ioctl.c: PIOCBIC */
2128 p->p_stops = 0;
2129 /* from procfs_ioctl.c: PIOCCONT */
2130 p->p_step = 0;
2131 wakeup(&p->p_step);
2132 }
2133 /*
2134 * Some signals have a process-wide effect and a per-thread
2135 * component. Most processing occurs when the process next
2136 * tries to cross the user boundary, however there are some
2137 * times when processing needs to be done immediatly, such as
2138 * waking up threads so that they can cross the user boundary.
2139 * We try do the per-process part here.
2140 */
2141 if (P_SHOULDSTOP(p)) {
2142 /*
2143 * The process is in stopped mode. All the threads should be
2144 * either winding down or already on the suspended queue.
2145 */
2146 if (p->p_flag & P_TRACED) {
2147 /*
2148 * The traced process is already stopped,
2149 * so no further action is necessary.
2150 * No signal can restart us.
2151 */
2152 goto out;
2153 }
2154
2155 if (sig == SIGKILL) {
2156 /*
2157 * SIGKILL sets process running.
2158 * It will die elsewhere.
2159 * All threads must be restarted.
2160 */
2161 p->p_flag &= ~P_STOPPED_SIG;
2162 goto runfast;
2163 }
2164
2165 if (prop & SA_CONT) {
2166 /*
2167 * If SIGCONT is default (or ignored), we continue the
2168 * process but don't leave the signal in sigqueue as
2169 * it has no further action. If SIGCONT is held, we
2170 * continue the process and leave the signal in
2171 * sigqueue. If the process catches SIGCONT, let it
2172 * handle the signal itself. If it isn't waiting on
2173 * an event, it goes back to run state.
2174 * Otherwise, process goes back to sleep state.
2175 */
2176 p->p_flag &= ~P_STOPPED_SIG;
2177 PROC_SLOCK(p);
2178 if (p->p_numthreads == p->p_suspcount) {
2179 PROC_SUNLOCK(p);
2180 p->p_flag |= P_CONTINUED;
2181 p->p_xstat = SIGCONT;
2182 PROC_LOCK(p->p_pptr);
2183 childproc_continued(p);
2184 PROC_UNLOCK(p->p_pptr);
2185 PROC_SLOCK(p);
2186 }
2187 if (action == SIG_DFL) {
2188 thread_unsuspend(p);
2189 PROC_SUNLOCK(p);
2190 sigqueue_delete(sigqueue, sig);
2191 goto out;
2192 }
2193 if (action == SIG_CATCH) {
2194 /*
2195 * The process wants to catch it so it needs
2196 * to run at least one thread, but which one?
2197 */
2198 PROC_SUNLOCK(p);
2199 goto runfast;
2200 }
2201 /*
2202 * The signal is not ignored or caught.
2203 */
2204 thread_unsuspend(p);
2205 PROC_SUNLOCK(p);
2206 goto out;
2207 }
2208
2209 if (prop & SA_STOP) {
2210 /*
2211 * Already stopped, don't need to stop again
2212 * (If we did the shell could get confused).
2213 * Just make sure the signal STOP bit set.
2214 */
2215 p->p_flag |= P_STOPPED_SIG;
2216 sigqueue_delete(sigqueue, sig);
2217 goto out;
2218 }
2219
2220 /*
2221 * All other kinds of signals:
2222 * If a thread is sleeping interruptibly, simulate a
2223 * wakeup so that when it is continued it will be made
2224 * runnable and can look at the signal. However, don't make
2225 * the PROCESS runnable, leave it stopped.
2226 * It may run a bit until it hits a thread_suspend_check().
2227 */
2228 wakeup_swapper = 0;
2229 PROC_SLOCK(p);
2230 thread_lock(td);
2231 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2232 wakeup_swapper = sleepq_abort(td, intrval);
2233 thread_unlock(td);
2234 PROC_SUNLOCK(p);
2235 if (wakeup_swapper)
2236 kick_proc0();
2237 goto out;
2238 /*
2239 * Mutexes are short lived. Threads waiting on them will
2240 * hit thread_suspend_check() soon.
2241 */
2242 } else if (p->p_state == PRS_NORMAL) {
2243 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2244 tdsigwakeup(td, sig, action, intrval);
2245 goto out;
2246 }
2247
2248 MPASS(action == SIG_DFL);
2249
2250 if (prop & SA_STOP) {
2251 if (p->p_flag & P_PPWAIT)
2252 goto out;
2253 p->p_flag |= P_STOPPED_SIG;
2254 p->p_xstat = sig;
2255 PROC_SLOCK(p);
2256 sig_suspend_threads(td, p, 1);
2257 if (p->p_numthreads == p->p_suspcount) {
2258 /*
2259 * only thread sending signal to another
2260 * process can reach here, if thread is sending
2261 * signal to its process, because thread does
2262 * not suspend itself here, p_numthreads
2263 * should never be equal to p_suspcount.
2264 */
2265 thread_stopped(p);
2266 PROC_SUNLOCK(p);
2267 sigqueue_delete_proc(p, p->p_xstat);
2268 } else
2269 PROC_SUNLOCK(p);
2270 goto out;
2271 }
2272 } else {
2273 /* Not in "NORMAL" state. discard the signal. */
2274 sigqueue_delete(sigqueue, sig);
2275 goto out;
2276 }
2277
2278 /*
2279 * The process is not stopped so we need to apply the signal to all the
2280 * running threads.
2281 */
2282runfast:
2283 tdsigwakeup(td, sig, action, intrval);
2284 PROC_SLOCK(p);
2285 thread_unsuspend(p);
2286 PROC_SUNLOCK(p);
2287out:
2288 /* If we jump here, proc slock should not be owned. */
2289 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2290 return (ret);
2291}
2292
2293/*
2294 * The force of a signal has been directed against a single
2295 * thread. We need to see what we can do about knocking it
2296 * out of any sleep it may be in etc.
2297 */
2298static void
2299tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2300{
2301 struct proc *p = td->td_proc;
2302 register int prop;
2303 int wakeup_swapper;
2304
2305 wakeup_swapper = 0;
2306 PROC_LOCK_ASSERT(p, MA_OWNED);
2307 prop = sigprop(sig);
2308
2309 PROC_SLOCK(p);
2310 thread_lock(td);
2311 /*
2312 * Bring the priority of a thread up if we want it to get
2313 * killed in this lifetime.
2314 */
2315 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2316 sched_prio(td, PUSER);
2317 if (TD_ON_SLEEPQ(td)) {
2318 /*
2319 * If thread is sleeping uninterruptibly
2320 * we can't interrupt the sleep... the signal will
2321 * be noticed when the process returns through
2322 * trap() or syscall().
2323 */
2324 if ((td->td_flags & TDF_SINTR) == 0)
2325 goto out;
2326 /*
2327 * If SIGCONT is default (or ignored) and process is
2328 * asleep, we are finished; the process should not
2329 * be awakened.
2330 */
2331 if ((prop & SA_CONT) && action == SIG_DFL) {
2332 thread_unlock(td);
2333 PROC_SUNLOCK(p);
2334 sigqueue_delete(&p->p_sigqueue, sig);
2335 /*
2336 * It may be on either list in this state.
2337 * Remove from both for now.
2338 */
2339 sigqueue_delete(&td->td_sigqueue, sig);
2340 return;
2341 }
2342
2343 /*
2344 * Give low priority threads a better chance to run.
2345 */
2346 if (td->td_priority > PUSER)
2347 sched_prio(td, PUSER);
2348
2349 wakeup_swapper = sleepq_abort(td, intrval);
2350 } else {
2351 /*
2352 * Other states do nothing with the signal immediately,
2353 * other than kicking ourselves if we are running.
2354 * It will either never be noticed, or noticed very soon.
2355 */
2356#ifdef SMP
2357 if (TD_IS_RUNNING(td) && td != curthread)
2358 forward_signal(td);
2359#endif
2360 }
2361out:
2362 PROC_SUNLOCK(p);
2363 thread_unlock(td);
2364 if (wakeup_swapper)
2365 kick_proc0();
2366}
2367
2368static void
2369sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2370{
2371 struct thread *td2;
2372 int wakeup_swapper;
2373
2374 PROC_LOCK_ASSERT(p, MA_OWNED);
2375 PROC_SLOCK_ASSERT(p, MA_OWNED);
2376
2377 wakeup_swapper = 0;
2378 FOREACH_THREAD_IN_PROC(p, td2) {
2379 thread_lock(td2);
2380 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2381 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2382 (td2->td_flags & TDF_SINTR)) {
2383 if (td2->td_flags & TDF_SBDRY) {
2384 if (TD_IS_SUSPENDED(td2))
2385 wakeup_swapper |=
2386 thread_unsuspend_one(td2);
2387 if (TD_ON_SLEEPQ(td2))
2388 wakeup_swapper |=
2389 sleepq_abort(td2, ERESTART);
2390 } else if (!TD_IS_SUSPENDED(td2)) {
2391 thread_suspend_one(td2);
2392 }
2393 } else if (!TD_IS_SUSPENDED(td2)) {
2394 if (sending || td != td2)
2395 td2->td_flags |= TDF_ASTPENDING;
2396#ifdef SMP
2397 if (TD_IS_RUNNING(td2) && td2 != td)
2398 forward_signal(td2);
2399#endif
2400 }
2401 thread_unlock(td2);
2402 }
2403 if (wakeup_swapper)
2404 kick_proc0();
2405}
2406
2407int
2408ptracestop(struct thread *td, int sig)
2409{
2410 struct proc *p = td->td_proc;
2411
2412 PROC_LOCK_ASSERT(p, MA_OWNED);
2413 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2414 &p->p_mtx.lock_object, "Stopping for traced signal");
2415
2416 td->td_dbgflags |= TDB_XSIG;
2417 td->td_xsig = sig;
2418 PROC_SLOCK(p);
2419 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2420 if (p->p_flag & P_SINGLE_EXIT) {
2421 td->td_dbgflags &= ~TDB_XSIG;
2422 PROC_SUNLOCK(p);
2423 return (sig);
2424 }
2425 /*
2426 * Just make wait() to work, the last stopped thread
2427 * will win.
2428 */
2429 p->p_xstat = sig;
2430 p->p_xthread = td;
2431 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2432 sig_suspend_threads(td, p, 0);
2433stopme:
2434 thread_suspend_switch(td);
2435 if (!(p->p_flag & P_TRACED)) {
2436 break;
2437 }
2438 if (td->td_dbgflags & TDB_SUSPEND) {
2439 if (p->p_flag & P_SINGLE_EXIT)
2440 break;
2441 goto stopme;
2442 }
2443 }
2444 PROC_SUNLOCK(p);
2445 return (td->td_xsig);
2446}
2447
2448static void
2449reschedule_signals(struct proc *p, sigset_t block, int flags)
2450{
2451 struct sigacts *ps;
2452 struct thread *td;
2453 int i;
2454
2455 PROC_LOCK_ASSERT(p, MA_OWNED);
2456
2457 ps = p->p_sigacts;
2458 for (i = 1; !SIGISEMPTY(block); i++) {
2459 if (!SIGISMEMBER(block, i))
2460 continue;
2461 SIGDELSET(block, i);
2462 if (!SIGISMEMBER(p->p_siglist, i))
2463 continue;
2464
2465 td = sigtd(p, i, 0);
2466 signotify(td);
2467 if (!(flags & SIGPROCMASK_PS_LOCKED))
2468 mtx_lock(&ps->ps_mtx);
2469 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, i))
2470 tdsigwakeup(td, i, SIG_CATCH,
2471 (SIGISMEMBER(ps->ps_sigintr, i) ? EINTR :
2472 ERESTART));
2473 if (!(flags & SIGPROCMASK_PS_LOCKED))
2474 mtx_unlock(&ps->ps_mtx);
2475 }
2476}
2477
2478void
2479tdsigcleanup(struct thread *td)
2480{
2481 struct proc *p;
2482 sigset_t unblocked;
2483
2484 p = td->td_proc;
2485 PROC_LOCK_ASSERT(p, MA_OWNED);
2486
2487 sigqueue_flush(&td->td_sigqueue);
2488 if (p->p_numthreads == 1)
2489 return;
2490
2491 /*
2492 * Since we cannot handle signals, notify signal post code
2493 * about this by filling the sigmask.
2494 *
2495 * Also, if needed, wake up thread(s) that do not block the
2496 * same signals as the exiting thread, since the thread might
2497 * have been selected for delivery and woken up.
2498 */
2499 SIGFILLSET(unblocked);
2500 SIGSETNAND(unblocked, td->td_sigmask);
2501 SIGFILLSET(td->td_sigmask);
2502 reschedule_signals(p, unblocked, 0);
2503
2504}
2505
2506/*
2507 * If the current process has received a signal (should be caught or cause
2508 * termination, should interrupt current syscall), return the signal number.
2509 * Stop signals with default action are processed immediately, then cleared;
2510 * they aren't returned. This is checked after each entry to the system for
2511 * a syscall or trap (though this can usually be done without calling issignal
2512 * by checking the pending signal masks in cursig.) The normal call
2513 * sequence is
2514 *
2515 * while (sig = cursig(curthread))
2516 * postsig(sig);
2517 */
2518static int
2519issignal(struct thread *td, int stop_allowed)
2520{
2521 struct proc *p;
2522 struct sigacts *ps;
2523 struct sigqueue *queue;
2524 sigset_t sigpending;
| 39
40#include "opt_compat.h"
41#include "opt_kdtrace.h"
42#include "opt_ktrace.h"
43#include "opt_core.h"
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/signalvar.h>
48#include <sys/vnode.h>
49#include <sys/acct.h>
50#include <sys/condvar.h>
51#include <sys/event.h>
52#include <sys/fcntl.h>
53#include <sys/imgact.h>
54#include <sys/kernel.h>
55#include <sys/ktr.h>
56#include <sys/ktrace.h>
57#include <sys/lock.h>
58#include <sys/malloc.h>
59#include <sys/mutex.h>
60#include <sys/namei.h>
61#include <sys/proc.h>
62#include <sys/posix4.h>
63#include <sys/pioctl.h>
64#include <sys/resourcevar.h>
65#include <sys/sdt.h>
66#include <sys/sbuf.h>
67#include <sys/sleepqueue.h>
68#include <sys/smp.h>
69#include <sys/stat.h>
70#include <sys/sx.h>
71#include <sys/syscallsubr.h>
72#include <sys/sysctl.h>
73#include <sys/sysent.h>
74#include <sys/syslog.h>
75#include <sys/sysproto.h>
76#include <sys/timers.h>
77#include <sys/unistd.h>
78#include <sys/wait.h>
79#include <vm/vm.h>
80#include <vm/vm_extern.h>
81#include <vm/uma.h>
82
83#include <sys/jail.h>
84
85#include <machine/cpu.h>
86
87#include <security/audit/audit.h>
88
89#define ONSIG 32 /* NSIG for osig* syscalls. XXX. */
90
91SDT_PROVIDER_DECLARE(proc);
92SDT_PROBE_DEFINE(proc, kernel, , signal_send);
93SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 0, "struct thread *");
94SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 1, "struct proc *");
95SDT_PROBE_ARGTYPE(proc, kernel, , signal_send, 2, "int");
96SDT_PROBE_DEFINE(proc, kernel, , signal_clear);
97SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 0, "int");
98SDT_PROBE_ARGTYPE(proc, kernel, , signal_clear, 1, "ksiginfo_t *");
99SDT_PROBE_DEFINE(proc, kernel, , signal_discard);
100SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 0, "struct thread *");
101SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 1, "struct proc *");
102SDT_PROBE_ARGTYPE(proc, kernel, , signal_discard, 2, "int");
103
104static int coredump(struct thread *);
105static char *expand_name(const char *, uid_t, pid_t, struct thread *, int);
106static int killpg1(struct thread *td, int sig, int pgid, int all,
107 ksiginfo_t *ksi);
108static int issignal(struct thread *td, int stop_allowed);
109static int sigprop(int sig);
110static int tdsendsignal(struct proc *p, struct thread *td, int sig,
111 ksiginfo_t *ksi);
112static void tdsigwakeup(struct thread *, int, sig_t, int);
113static void sig_suspend_threads(struct thread *, struct proc *, int);
114static int filt_sigattach(struct knote *kn);
115static void filt_sigdetach(struct knote *kn);
116static int filt_signal(struct knote *kn, long hint);
117static struct thread *sigtd(struct proc *p, int sig, int prop);
118static void sigqueue_start(void);
119
120static uma_zone_t ksiginfo_zone = NULL;
121struct filterops sig_filtops = {
122 .f_isfd = 0,
123 .f_attach = filt_sigattach,
124 .f_detach = filt_sigdetach,
125 .f_event = filt_signal,
126};
127
128int kern_logsigexit = 1;
129SYSCTL_INT(_kern, KERN_LOGSIGEXIT, logsigexit, CTLFLAG_RW,
130 &kern_logsigexit, 0,
131 "Log processes quitting on abnormal signals to syslog(3)");
132
133static int kern_forcesigexit = 1;
134SYSCTL_INT(_kern, OID_AUTO, forcesigexit, CTLFLAG_RW,
135 &kern_forcesigexit, 0, "Force trap signal to be handled");
136
137SYSCTL_NODE(_kern, OID_AUTO, sigqueue, CTLFLAG_RW, 0, "POSIX real time signal");
138
139static int max_pending_per_proc = 128;
140SYSCTL_INT(_kern_sigqueue, OID_AUTO, max_pending_per_proc, CTLFLAG_RW,
141 &max_pending_per_proc, 0, "Max pending signals per proc");
142
143static int preallocate_siginfo = 1024;
144TUNABLE_INT("kern.sigqueue.preallocate", &preallocate_siginfo);
145SYSCTL_INT(_kern_sigqueue, OID_AUTO, preallocate, CTLFLAG_RD,
146 &preallocate_siginfo, 0, "Preallocated signal memory size");
147
148static int signal_overflow = 0;
149SYSCTL_INT(_kern_sigqueue, OID_AUTO, overflow, CTLFLAG_RD,
150 &signal_overflow, 0, "Number of signals overflew");
151
152static int signal_alloc_fail = 0;
153SYSCTL_INT(_kern_sigqueue, OID_AUTO, alloc_fail, CTLFLAG_RD,
154 &signal_alloc_fail, 0, "signals failed to be allocated");
155
156SYSINIT(signal, SI_SUB_P1003_1B, SI_ORDER_FIRST+3, sigqueue_start, NULL);
157
158/*
159 * Policy -- Can ucred cr1 send SIGIO to process cr2?
160 * Should use cr_cansignal() once cr_cansignal() allows SIGIO and SIGURG
161 * in the right situations.
162 */
163#define CANSIGIO(cr1, cr2) \
164 ((cr1)->cr_uid == 0 || \
165 (cr1)->cr_ruid == (cr2)->cr_ruid || \
166 (cr1)->cr_uid == (cr2)->cr_ruid || \
167 (cr1)->cr_ruid == (cr2)->cr_uid || \
168 (cr1)->cr_uid == (cr2)->cr_uid)
169
170int sugid_coredump;
171SYSCTL_INT(_kern, OID_AUTO, sugid_coredump, CTLFLAG_RW,
172 &sugid_coredump, 0, "Allow setuid and setgid processes to dump core");
173
174static int do_coredump = 1;
175SYSCTL_INT(_kern, OID_AUTO, coredump, CTLFLAG_RW,
176 &do_coredump, 0, "Enable/Disable coredumps");
177
178static int set_core_nodump_flag = 0;
179SYSCTL_INT(_kern, OID_AUTO, nodump_coredump, CTLFLAG_RW, &set_core_nodump_flag,
180 0, "Enable setting the NODUMP flag on coredump files");
181
182/*
183 * Signal properties and actions.
184 * The array below categorizes the signals and their default actions
185 * according to the following properties:
186 */
187#define SA_KILL 0x01 /* terminates process by default */
188#define SA_CORE 0x02 /* ditto and coredumps */
189#define SA_STOP 0x04 /* suspend process */
190#define SA_TTYSTOP 0x08 /* ditto, from tty */
191#define SA_IGNORE 0x10 /* ignore by default */
192#define SA_CONT 0x20 /* continue if suspended */
193#define SA_CANTMASK 0x40 /* non-maskable, catchable */
194#define SA_PROC 0x80 /* deliverable to any thread */
195
196static int sigproptbl[NSIG] = {
197 SA_KILL|SA_PROC, /* SIGHUP */
198 SA_KILL|SA_PROC, /* SIGINT */
199 SA_KILL|SA_CORE|SA_PROC, /* SIGQUIT */
200 SA_KILL|SA_CORE, /* SIGILL */
201 SA_KILL|SA_CORE, /* SIGTRAP */
202 SA_KILL|SA_CORE, /* SIGABRT */
203 SA_KILL|SA_CORE|SA_PROC, /* SIGEMT */
204 SA_KILL|SA_CORE, /* SIGFPE */
205 SA_KILL|SA_PROC, /* SIGKILL */
206 SA_KILL|SA_CORE, /* SIGBUS */
207 SA_KILL|SA_CORE, /* SIGSEGV */
208 SA_KILL|SA_CORE, /* SIGSYS */
209 SA_KILL|SA_PROC, /* SIGPIPE */
210 SA_KILL|SA_PROC, /* SIGALRM */
211 SA_KILL|SA_PROC, /* SIGTERM */
212 SA_IGNORE|SA_PROC, /* SIGURG */
213 SA_STOP|SA_PROC, /* SIGSTOP */
214 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTSTP */
215 SA_IGNORE|SA_CONT|SA_PROC, /* SIGCONT */
216 SA_IGNORE|SA_PROC, /* SIGCHLD */
217 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTIN */
218 SA_STOP|SA_TTYSTOP|SA_PROC, /* SIGTTOU */
219 SA_IGNORE|SA_PROC, /* SIGIO */
220 SA_KILL, /* SIGXCPU */
221 SA_KILL, /* SIGXFSZ */
222 SA_KILL|SA_PROC, /* SIGVTALRM */
223 SA_KILL|SA_PROC, /* SIGPROF */
224 SA_IGNORE|SA_PROC, /* SIGWINCH */
225 SA_IGNORE|SA_PROC, /* SIGINFO */
226 SA_KILL|SA_PROC, /* SIGUSR1 */
227 SA_KILL|SA_PROC, /* SIGUSR2 */
228};
229
230static void reschedule_signals(struct proc *p, sigset_t block, int flags);
231
232static void
233sigqueue_start(void)
234{
235 ksiginfo_zone = uma_zcreate("ksiginfo", sizeof(ksiginfo_t),
236 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
237 uma_prealloc(ksiginfo_zone, preallocate_siginfo);
238 p31b_setcfg(CTL_P1003_1B_REALTIME_SIGNALS, _POSIX_REALTIME_SIGNALS);
239 p31b_setcfg(CTL_P1003_1B_RTSIG_MAX, SIGRTMAX - SIGRTMIN + 1);
240 p31b_setcfg(CTL_P1003_1B_SIGQUEUE_MAX, max_pending_per_proc);
241}
242
243ksiginfo_t *
244ksiginfo_alloc(int wait)
245{
246 int flags;
247
248 flags = M_ZERO;
249 if (! wait)
250 flags |= M_NOWAIT;
251 if (ksiginfo_zone != NULL)
252 return ((ksiginfo_t *)uma_zalloc(ksiginfo_zone, flags));
253 return (NULL);
254}
255
256void
257ksiginfo_free(ksiginfo_t *ksi)
258{
259 uma_zfree(ksiginfo_zone, ksi);
260}
261
262static __inline int
263ksiginfo_tryfree(ksiginfo_t *ksi)
264{
265 if (!(ksi->ksi_flags & KSI_EXT)) {
266 uma_zfree(ksiginfo_zone, ksi);
267 return (1);
268 }
269 return (0);
270}
271
272void
273sigqueue_init(sigqueue_t *list, struct proc *p)
274{
275 SIGEMPTYSET(list->sq_signals);
276 SIGEMPTYSET(list->sq_kill);
277 TAILQ_INIT(&list->sq_list);
278 list->sq_proc = p;
279 list->sq_flags = SQ_INIT;
280}
281
282/*
283 * Get a signal's ksiginfo.
284 * Return:
285 * 0 - signal not found
286 * others - signal number
287 */
288static int
289sigqueue_get(sigqueue_t *sq, int signo, ksiginfo_t *si)
290{
291 struct proc *p = sq->sq_proc;
292 struct ksiginfo *ksi, *next;
293 int count = 0;
294
295 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
296
297 if (!SIGISMEMBER(sq->sq_signals, signo))
298 return (0);
299
300 if (SIGISMEMBER(sq->sq_kill, signo)) {
301 count++;
302 SIGDELSET(sq->sq_kill, signo);
303 }
304
305 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
306 if (ksi->ksi_signo == signo) {
307 if (count == 0) {
308 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
309 ksi->ksi_sigq = NULL;
310 ksiginfo_copy(ksi, si);
311 if (ksiginfo_tryfree(ksi) && p != NULL)
312 p->p_pendingcnt--;
313 }
314 if (++count > 1)
315 break;
316 }
317 }
318
319 if (count <= 1)
320 SIGDELSET(sq->sq_signals, signo);
321 si->ksi_signo = signo;
322 return (signo);
323}
324
325void
326sigqueue_take(ksiginfo_t *ksi)
327{
328 struct ksiginfo *kp;
329 struct proc *p;
330 sigqueue_t *sq;
331
332 if (ksi == NULL || (sq = ksi->ksi_sigq) == NULL)
333 return;
334
335 p = sq->sq_proc;
336 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
337 ksi->ksi_sigq = NULL;
338 if (!(ksi->ksi_flags & KSI_EXT) && p != NULL)
339 p->p_pendingcnt--;
340
341 for (kp = TAILQ_FIRST(&sq->sq_list); kp != NULL;
342 kp = TAILQ_NEXT(kp, ksi_link)) {
343 if (kp->ksi_signo == ksi->ksi_signo)
344 break;
345 }
346 if (kp == NULL && !SIGISMEMBER(sq->sq_kill, ksi->ksi_signo))
347 SIGDELSET(sq->sq_signals, ksi->ksi_signo);
348}
349
350static int
351sigqueue_add(sigqueue_t *sq, int signo, ksiginfo_t *si)
352{
353 struct proc *p = sq->sq_proc;
354 struct ksiginfo *ksi;
355 int ret = 0;
356
357 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
358
359 if (signo == SIGKILL || signo == SIGSTOP || si == NULL) {
360 SIGADDSET(sq->sq_kill, signo);
361 goto out_set_bit;
362 }
363
364 /* directly insert the ksi, don't copy it */
365 if (si->ksi_flags & KSI_INS) {
366 if (si->ksi_flags & KSI_HEAD)
367 TAILQ_INSERT_HEAD(&sq->sq_list, si, ksi_link);
368 else
369 TAILQ_INSERT_TAIL(&sq->sq_list, si, ksi_link);
370 si->ksi_sigq = sq;
371 goto out_set_bit;
372 }
373
374 if (__predict_false(ksiginfo_zone == NULL)) {
375 SIGADDSET(sq->sq_kill, signo);
376 goto out_set_bit;
377 }
378
379 if (p != NULL && p->p_pendingcnt >= max_pending_per_proc) {
380 signal_overflow++;
381 ret = EAGAIN;
382 } else if ((ksi = ksiginfo_alloc(0)) == NULL) {
383 signal_alloc_fail++;
384 ret = EAGAIN;
385 } else {
386 if (p != NULL)
387 p->p_pendingcnt++;
388 ksiginfo_copy(si, ksi);
389 ksi->ksi_signo = signo;
390 if (si->ksi_flags & KSI_HEAD)
391 TAILQ_INSERT_HEAD(&sq->sq_list, ksi, ksi_link);
392 else
393 TAILQ_INSERT_TAIL(&sq->sq_list, ksi, ksi_link);
394 ksi->ksi_sigq = sq;
395 }
396
397 if ((si->ksi_flags & KSI_TRAP) != 0 ||
398 (si->ksi_flags & KSI_SIGQ) == 0) {
399 if (ret != 0)
400 SIGADDSET(sq->sq_kill, signo);
401 ret = 0;
402 goto out_set_bit;
403 }
404
405 if (ret != 0)
406 return (ret);
407
408out_set_bit:
409 SIGADDSET(sq->sq_signals, signo);
410 return (ret);
411}
412
413void
414sigqueue_flush(sigqueue_t *sq)
415{
416 struct proc *p = sq->sq_proc;
417 ksiginfo_t *ksi;
418
419 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
420
421 if (p != NULL)
422 PROC_LOCK_ASSERT(p, MA_OWNED);
423
424 while ((ksi = TAILQ_FIRST(&sq->sq_list)) != NULL) {
425 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
426 ksi->ksi_sigq = NULL;
427 if (ksiginfo_tryfree(ksi) && p != NULL)
428 p->p_pendingcnt--;
429 }
430
431 SIGEMPTYSET(sq->sq_signals);
432 SIGEMPTYSET(sq->sq_kill);
433}
434
435static void
436sigqueue_collect_set(sigqueue_t *sq, sigset_t *set)
437{
438 ksiginfo_t *ksi;
439
440 KASSERT(sq->sq_flags & SQ_INIT, ("sigqueue not inited"));
441
442 TAILQ_FOREACH(ksi, &sq->sq_list, ksi_link)
443 SIGADDSET(*set, ksi->ksi_signo);
444 SIGSETOR(*set, sq->sq_kill);
445}
446
447static void
448sigqueue_move_set(sigqueue_t *src, sigqueue_t *dst, sigset_t *setp)
449{
450 sigset_t tmp, set;
451 struct proc *p1, *p2;
452 ksiginfo_t *ksi, *next;
453
454 KASSERT(src->sq_flags & SQ_INIT, ("src sigqueue not inited"));
455 KASSERT(dst->sq_flags & SQ_INIT, ("dst sigqueue not inited"));
456 /*
457 * make a copy, this allows setp to point to src or dst
458 * sq_signals without trouble.
459 */
460 set = *setp;
461 p1 = src->sq_proc;
462 p2 = dst->sq_proc;
463 /* Move siginfo to target list */
464 TAILQ_FOREACH_SAFE(ksi, &src->sq_list, ksi_link, next) {
465 if (SIGISMEMBER(set, ksi->ksi_signo)) {
466 TAILQ_REMOVE(&src->sq_list, ksi, ksi_link);
467 if (p1 != NULL)
468 p1->p_pendingcnt--;
469 TAILQ_INSERT_TAIL(&dst->sq_list, ksi, ksi_link);
470 ksi->ksi_sigq = dst;
471 if (p2 != NULL)
472 p2->p_pendingcnt++;
473 }
474 }
475
476 /* Move pending bits to target list */
477 tmp = src->sq_kill;
478 SIGSETAND(tmp, set);
479 SIGSETOR(dst->sq_kill, tmp);
480 SIGSETNAND(src->sq_kill, tmp);
481
482 tmp = src->sq_signals;
483 SIGSETAND(tmp, set);
484 SIGSETOR(dst->sq_signals, tmp);
485 SIGSETNAND(src->sq_signals, tmp);
486
487 /* Finally, rescan src queue and set pending bits for it */
488 sigqueue_collect_set(src, &src->sq_signals);
489}
490
491static void
492sigqueue_move(sigqueue_t *src, sigqueue_t *dst, int signo)
493{
494 sigset_t set;
495
496 SIGEMPTYSET(set);
497 SIGADDSET(set, signo);
498 sigqueue_move_set(src, dst, &set);
499}
500
501static void
502sigqueue_delete_set(sigqueue_t *sq, sigset_t *set)
503{
504 struct proc *p = sq->sq_proc;
505 ksiginfo_t *ksi, *next;
506
507 KASSERT(sq->sq_flags & SQ_INIT, ("src sigqueue not inited"));
508
509 /* Remove siginfo queue */
510 TAILQ_FOREACH_SAFE(ksi, &sq->sq_list, ksi_link, next) {
511 if (SIGISMEMBER(*set, ksi->ksi_signo)) {
512 TAILQ_REMOVE(&sq->sq_list, ksi, ksi_link);
513 ksi->ksi_sigq = NULL;
514 if (ksiginfo_tryfree(ksi) && p != NULL)
515 p->p_pendingcnt--;
516 }
517 }
518 SIGSETNAND(sq->sq_kill, *set);
519 SIGSETNAND(sq->sq_signals, *set);
520 /* Finally, rescan queue and set pending bits for it */
521 sigqueue_collect_set(sq, &sq->sq_signals);
522}
523
524void
525sigqueue_delete(sigqueue_t *sq, int signo)
526{
527 sigset_t set;
528
529 SIGEMPTYSET(set);
530 SIGADDSET(set, signo);
531 sigqueue_delete_set(sq, &set);
532}
533
534/* Remove a set of signals for a process */
535static void
536sigqueue_delete_set_proc(struct proc *p, sigset_t *set)
537{
538 sigqueue_t worklist;
539 struct thread *td0;
540
541 PROC_LOCK_ASSERT(p, MA_OWNED);
542
543 sigqueue_init(&worklist, NULL);
544 sigqueue_move_set(&p->p_sigqueue, &worklist, set);
545
546 FOREACH_THREAD_IN_PROC(p, td0)
547 sigqueue_move_set(&td0->td_sigqueue, &worklist, set);
548
549 sigqueue_flush(&worklist);
550}
551
552void
553sigqueue_delete_proc(struct proc *p, int signo)
554{
555 sigset_t set;
556
557 SIGEMPTYSET(set);
558 SIGADDSET(set, signo);
559 sigqueue_delete_set_proc(p, &set);
560}
561
562static void
563sigqueue_delete_stopmask_proc(struct proc *p)
564{
565 sigset_t set;
566
567 SIGEMPTYSET(set);
568 SIGADDSET(set, SIGSTOP);
569 SIGADDSET(set, SIGTSTP);
570 SIGADDSET(set, SIGTTIN);
571 SIGADDSET(set, SIGTTOU);
572 sigqueue_delete_set_proc(p, &set);
573}
574
575/*
576 * Determine signal that should be delivered to process p, the current
577 * process, 0 if none. If there is a pending stop signal with default
578 * action, the process stops in issignal().
579 */
580int
581cursig(struct thread *td, int stop_allowed)
582{
583 PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
584 KASSERT(stop_allowed == SIG_STOP_ALLOWED ||
585 stop_allowed == SIG_STOP_NOT_ALLOWED, ("cursig: stop_allowed"));
586 mtx_assert(&td->td_proc->p_sigacts->ps_mtx, MA_OWNED);
587 THREAD_LOCK_ASSERT(td, MA_NOTOWNED);
588 return (SIGPENDING(td) ? issignal(td, stop_allowed) : 0);
589}
590
591/*
592 * Arrange for ast() to handle unmasked pending signals on return to user
593 * mode. This must be called whenever a signal is added to td_sigqueue or
594 * unmasked in td_sigmask.
595 */
596void
597signotify(struct thread *td)
598{
599 struct proc *p;
600
601 p = td->td_proc;
602
603 PROC_LOCK_ASSERT(p, MA_OWNED);
604
605 if (SIGPENDING(td)) {
606 thread_lock(td);
607 td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
608 thread_unlock(td);
609 }
610}
611
612int
613sigonstack(size_t sp)
614{
615 struct thread *td = curthread;
616
617 return ((td->td_pflags & TDP_ALTSTACK) ?
618#if defined(COMPAT_43)
619 ((td->td_sigstk.ss_size == 0) ?
620 (td->td_sigstk.ss_flags & SS_ONSTACK) :
621 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size))
622#else
623 ((sp - (size_t)td->td_sigstk.ss_sp) < td->td_sigstk.ss_size)
624#endif
625 : 0);
626}
627
628static __inline int
629sigprop(int sig)
630{
631
632 if (sig > 0 && sig < NSIG)
633 return (sigproptbl[_SIG_IDX(sig)]);
634 return (0);
635}
636
637int
638sig_ffs(sigset_t *set)
639{
640 int i;
641
642 for (i = 0; i < _SIG_WORDS; i++)
643 if (set->__bits[i])
644 return (ffs(set->__bits[i]) + (i * 32));
645 return (0);
646}
647
648/*
649 * kern_sigaction
650 * sigaction
651 * freebsd4_sigaction
652 * osigaction
653 */
654int
655kern_sigaction(td, sig, act, oact, flags)
656 struct thread *td;
657 register int sig;
658 struct sigaction *act, *oact;
659 int flags;
660{
661 struct sigacts *ps;
662 struct proc *p = td->td_proc;
663
664 if (!_SIG_VALID(sig))
665 return (EINVAL);
666
667 PROC_LOCK(p);
668 ps = p->p_sigacts;
669 mtx_lock(&ps->ps_mtx);
670 if (oact) {
671 oact->sa_mask = ps->ps_catchmask[_SIG_IDX(sig)];
672 oact->sa_flags = 0;
673 if (SIGISMEMBER(ps->ps_sigonstack, sig))
674 oact->sa_flags |= SA_ONSTACK;
675 if (!SIGISMEMBER(ps->ps_sigintr, sig))
676 oact->sa_flags |= SA_RESTART;
677 if (SIGISMEMBER(ps->ps_sigreset, sig))
678 oact->sa_flags |= SA_RESETHAND;
679 if (SIGISMEMBER(ps->ps_signodefer, sig))
680 oact->sa_flags |= SA_NODEFER;
681 if (SIGISMEMBER(ps->ps_siginfo, sig)) {
682 oact->sa_flags |= SA_SIGINFO;
683 oact->sa_sigaction =
684 (__siginfohandler_t *)ps->ps_sigact[_SIG_IDX(sig)];
685 } else
686 oact->sa_handler = ps->ps_sigact[_SIG_IDX(sig)];
687 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDSTOP)
688 oact->sa_flags |= SA_NOCLDSTOP;
689 if (sig == SIGCHLD && ps->ps_flag & PS_NOCLDWAIT)
690 oact->sa_flags |= SA_NOCLDWAIT;
691 }
692 if (act) {
693 if ((sig == SIGKILL || sig == SIGSTOP) &&
694 act->sa_handler != SIG_DFL) {
695 mtx_unlock(&ps->ps_mtx);
696 PROC_UNLOCK(p);
697 return (EINVAL);
698 }
699
700 /*
701 * Change setting atomically.
702 */
703
704 ps->ps_catchmask[_SIG_IDX(sig)] = act->sa_mask;
705 SIG_CANTMASK(ps->ps_catchmask[_SIG_IDX(sig)]);
706 if (act->sa_flags & SA_SIGINFO) {
707 ps->ps_sigact[_SIG_IDX(sig)] =
708 (__sighandler_t *)act->sa_sigaction;
709 SIGADDSET(ps->ps_siginfo, sig);
710 } else {
711 ps->ps_sigact[_SIG_IDX(sig)] = act->sa_handler;
712 SIGDELSET(ps->ps_siginfo, sig);
713 }
714 if (!(act->sa_flags & SA_RESTART))
715 SIGADDSET(ps->ps_sigintr, sig);
716 else
717 SIGDELSET(ps->ps_sigintr, sig);
718 if (act->sa_flags & SA_ONSTACK)
719 SIGADDSET(ps->ps_sigonstack, sig);
720 else
721 SIGDELSET(ps->ps_sigonstack, sig);
722 if (act->sa_flags & SA_RESETHAND)
723 SIGADDSET(ps->ps_sigreset, sig);
724 else
725 SIGDELSET(ps->ps_sigreset, sig);
726 if (act->sa_flags & SA_NODEFER)
727 SIGADDSET(ps->ps_signodefer, sig);
728 else
729 SIGDELSET(ps->ps_signodefer, sig);
730 if (sig == SIGCHLD) {
731 if (act->sa_flags & SA_NOCLDSTOP)
732 ps->ps_flag |= PS_NOCLDSTOP;
733 else
734 ps->ps_flag &= ~PS_NOCLDSTOP;
735 if (act->sa_flags & SA_NOCLDWAIT) {
736 /*
737 * Paranoia: since SA_NOCLDWAIT is implemented
738 * by reparenting the dying child to PID 1 (and
739 * trust it to reap the zombie), PID 1 itself
740 * is forbidden to set SA_NOCLDWAIT.
741 */
742 if (p->p_pid == 1)
743 ps->ps_flag &= ~PS_NOCLDWAIT;
744 else
745 ps->ps_flag |= PS_NOCLDWAIT;
746 } else
747 ps->ps_flag &= ~PS_NOCLDWAIT;
748 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
749 ps->ps_flag |= PS_CLDSIGIGN;
750 else
751 ps->ps_flag &= ~PS_CLDSIGIGN;
752 }
753 /*
754 * Set bit in ps_sigignore for signals that are set to SIG_IGN,
755 * and for signals set to SIG_DFL where the default is to
756 * ignore. However, don't put SIGCONT in ps_sigignore, as we
757 * have to restart the process.
758 */
759 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
760 (sigprop(sig) & SA_IGNORE &&
761 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
762 /* never to be seen again */
763 sigqueue_delete_proc(p, sig);
764 if (sig != SIGCONT)
765 /* easier in psignal */
766 SIGADDSET(ps->ps_sigignore, sig);
767 SIGDELSET(ps->ps_sigcatch, sig);
768 } else {
769 SIGDELSET(ps->ps_sigignore, sig);
770 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)
771 SIGDELSET(ps->ps_sigcatch, sig);
772 else
773 SIGADDSET(ps->ps_sigcatch, sig);
774 }
775#ifdef COMPAT_FREEBSD4
776 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
777 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
778 (flags & KSA_FREEBSD4) == 0)
779 SIGDELSET(ps->ps_freebsd4, sig);
780 else
781 SIGADDSET(ps->ps_freebsd4, sig);
782#endif
783#ifdef COMPAT_43
784 if (ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN ||
785 ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL ||
786 (flags & KSA_OSIGSET) == 0)
787 SIGDELSET(ps->ps_osigset, sig);
788 else
789 SIGADDSET(ps->ps_osigset, sig);
790#endif
791 }
792 mtx_unlock(&ps->ps_mtx);
793 PROC_UNLOCK(p);
794 return (0);
795}
796
797#ifndef _SYS_SYSPROTO_H_
798struct sigaction_args {
799 int sig;
800 struct sigaction *act;
801 struct sigaction *oact;
802};
803#endif
804int
805sigaction(td, uap)
806 struct thread *td;
807 register struct sigaction_args *uap;
808{
809 struct sigaction act, oact;
810 register struct sigaction *actp, *oactp;
811 int error;
812
813 actp = (uap->act != NULL) ? &act : NULL;
814 oactp = (uap->oact != NULL) ? &oact : NULL;
815 if (actp) {
816 error = copyin(uap->act, actp, sizeof(act));
817 if (error)
818 return (error);
819 }
820 error = kern_sigaction(td, uap->sig, actp, oactp, 0);
821 if (oactp && !error)
822 error = copyout(oactp, uap->oact, sizeof(oact));
823 return (error);
824}
825
826#ifdef COMPAT_FREEBSD4
827#ifndef _SYS_SYSPROTO_H_
828struct freebsd4_sigaction_args {
829 int sig;
830 struct sigaction *act;
831 struct sigaction *oact;
832};
833#endif
834int
835freebsd4_sigaction(td, uap)
836 struct thread *td;
837 register struct freebsd4_sigaction_args *uap;
838{
839 struct sigaction act, oact;
840 register struct sigaction *actp, *oactp;
841 int error;
842
843
844 actp = (uap->act != NULL) ? &act : NULL;
845 oactp = (uap->oact != NULL) ? &oact : NULL;
846 if (actp) {
847 error = copyin(uap->act, actp, sizeof(act));
848 if (error)
849 return (error);
850 }
851 error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
852 if (oactp && !error)
853 error = copyout(oactp, uap->oact, sizeof(oact));
854 return (error);
855}
856#endif /* COMAPT_FREEBSD4 */
857
858#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
859#ifndef _SYS_SYSPROTO_H_
860struct osigaction_args {
861 int signum;
862 struct osigaction *nsa;
863 struct osigaction *osa;
864};
865#endif
866int
867osigaction(td, uap)
868 struct thread *td;
869 register struct osigaction_args *uap;
870{
871 struct osigaction sa;
872 struct sigaction nsa, osa;
873 register struct sigaction *nsap, *osap;
874 int error;
875
876 if (uap->signum <= 0 || uap->signum >= ONSIG)
877 return (EINVAL);
878
879 nsap = (uap->nsa != NULL) ? &nsa : NULL;
880 osap = (uap->osa != NULL) ? &osa : NULL;
881
882 if (nsap) {
883 error = copyin(uap->nsa, &sa, sizeof(sa));
884 if (error)
885 return (error);
886 nsap->sa_handler = sa.sa_handler;
887 nsap->sa_flags = sa.sa_flags;
888 OSIG2SIG(sa.sa_mask, nsap->sa_mask);
889 }
890 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
891 if (osap && !error) {
892 sa.sa_handler = osap->sa_handler;
893 sa.sa_flags = osap->sa_flags;
894 SIG2OSIG(osap->sa_mask, sa.sa_mask);
895 error = copyout(&sa, uap->osa, sizeof(sa));
896 }
897 return (error);
898}
899
900#if !defined(__i386__)
901/* Avoid replicating the same stub everywhere */
902int
903osigreturn(td, uap)
904 struct thread *td;
905 struct osigreturn_args *uap;
906{
907
908 return (nosys(td, (struct nosys_args *)uap));
909}
910#endif
911#endif /* COMPAT_43 */
912
913/*
914 * Initialize signal state for process 0;
915 * set to ignore signals that are ignored by default.
916 */
917void
918siginit(p)
919 struct proc *p;
920{
921 register int i;
922 struct sigacts *ps;
923
924 PROC_LOCK(p);
925 ps = p->p_sigacts;
926 mtx_lock(&ps->ps_mtx);
927 for (i = 1; i <= NSIG; i++)
928 if (sigprop(i) & SA_IGNORE && i != SIGCONT)
929 SIGADDSET(ps->ps_sigignore, i);
930 mtx_unlock(&ps->ps_mtx);
931 PROC_UNLOCK(p);
932}
933
934/*
935 * Reset signals for an exec of the specified process.
936 */
937void
938execsigs(struct proc *p)
939{
940 struct sigacts *ps;
941 int sig;
942 struct thread *td;
943
944 /*
945 * Reset caught signals. Held signals remain held
946 * through td_sigmask (unless they were caught,
947 * and are now ignored by default).
948 */
949 PROC_LOCK_ASSERT(p, MA_OWNED);
950 td = FIRST_THREAD_IN_PROC(p);
951 ps = p->p_sigacts;
952 mtx_lock(&ps->ps_mtx);
953 while (SIGNOTEMPTY(ps->ps_sigcatch)) {
954 sig = sig_ffs(&ps->ps_sigcatch);
955 SIGDELSET(ps->ps_sigcatch, sig);
956 if (sigprop(sig) & SA_IGNORE) {
957 if (sig != SIGCONT)
958 SIGADDSET(ps->ps_sigignore, sig);
959 sigqueue_delete_proc(p, sig);
960 }
961 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
962 }
963 /*
964 * Reset stack state to the user stack.
965 * Clear set of signals caught on the signal stack.
966 */
967 td->td_sigstk.ss_flags = SS_DISABLE;
968 td->td_sigstk.ss_size = 0;
969 td->td_sigstk.ss_sp = 0;
970 td->td_pflags &= ~TDP_ALTSTACK;
971 /*
972 * Reset no zombies if child dies flag as Solaris does.
973 */
974 ps->ps_flag &= ~(PS_NOCLDWAIT | PS_CLDSIGIGN);
975 if (ps->ps_sigact[_SIG_IDX(SIGCHLD)] == SIG_IGN)
976 ps->ps_sigact[_SIG_IDX(SIGCHLD)] = SIG_DFL;
977 mtx_unlock(&ps->ps_mtx);
978}
979
980/*
981 * kern_sigprocmask()
982 *
983 * Manipulate signal mask.
984 */
985int
986kern_sigprocmask(struct thread *td, int how, sigset_t *set, sigset_t *oset,
987 int flags)
988{
989 sigset_t new_block, oset1;
990 struct proc *p;
991 int error;
992
993 p = td->td_proc;
994 if (!(flags & SIGPROCMASK_PROC_LOCKED))
995 PROC_LOCK(p);
996 if (oset != NULL)
997 *oset = td->td_sigmask;
998
999 error = 0;
1000 SIGEMPTYSET(new_block);
1001 if (set != NULL) {
1002 switch (how) {
1003 case SIG_BLOCK:
1004 SIG_CANTMASK(*set);
1005 oset1 = td->td_sigmask;
1006 SIGSETOR(td->td_sigmask, *set);
1007 new_block = td->td_sigmask;
1008 SIGSETNAND(new_block, oset1);
1009 break;
1010 case SIG_UNBLOCK:
1011 SIGSETNAND(td->td_sigmask, *set);
1012 signotify(td);
1013 break;
1014 case SIG_SETMASK:
1015 SIG_CANTMASK(*set);
1016 oset1 = td->td_sigmask;
1017 if (flags & SIGPROCMASK_OLD)
1018 SIGSETLO(td->td_sigmask, *set);
1019 else
1020 td->td_sigmask = *set;
1021 new_block = td->td_sigmask;
1022 SIGSETNAND(new_block, oset1);
1023 signotify(td);
1024 break;
1025 default:
1026 error = EINVAL;
1027 break;
1028 }
1029 }
1030
1031 /*
1032 * The new_block set contains signals that were not previously
1033 * blocked, but are blocked now.
1034 *
1035 * In case we block any signal that was not previously blocked
1036 * for td, and process has the signal pending, try to schedule
1037 * signal delivery to some thread that does not block the signal,
1038 * possibly waking it up.
1039 */
1040 if (p->p_numthreads != 1)
1041 reschedule_signals(p, new_block, flags);
1042
1043 if (!(flags & SIGPROCMASK_PROC_LOCKED))
1044 PROC_UNLOCK(p);
1045 return (error);
1046}
1047
1048#ifndef _SYS_SYSPROTO_H_
1049struct sigprocmask_args {
1050 int how;
1051 const sigset_t *set;
1052 sigset_t *oset;
1053};
1054#endif
1055int
1056sigprocmask(td, uap)
1057 register struct thread *td;
1058 struct sigprocmask_args *uap;
1059{
1060 sigset_t set, oset;
1061 sigset_t *setp, *osetp;
1062 int error;
1063
1064 setp = (uap->set != NULL) ? &set : NULL;
1065 osetp = (uap->oset != NULL) ? &oset : NULL;
1066 if (setp) {
1067 error = copyin(uap->set, setp, sizeof(set));
1068 if (error)
1069 return (error);
1070 }
1071 error = kern_sigprocmask(td, uap->how, setp, osetp, 0);
1072 if (osetp && !error) {
1073 error = copyout(osetp, uap->oset, sizeof(oset));
1074 }
1075 return (error);
1076}
1077
1078#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1079#ifndef _SYS_SYSPROTO_H_
1080struct osigprocmask_args {
1081 int how;
1082 osigset_t mask;
1083};
1084#endif
1085int
1086osigprocmask(td, uap)
1087 register struct thread *td;
1088 struct osigprocmask_args *uap;
1089{
1090 sigset_t set, oset;
1091 int error;
1092
1093 OSIG2SIG(uap->mask, set);
1094 error = kern_sigprocmask(td, uap->how, &set, &oset, 1);
1095 SIG2OSIG(oset, td->td_retval[0]);
1096 return (error);
1097}
1098#endif /* COMPAT_43 */
1099
1100int
1101sigwait(struct thread *td, struct sigwait_args *uap)
1102{
1103 ksiginfo_t ksi;
1104 sigset_t set;
1105 int error;
1106
1107 error = copyin(uap->set, &set, sizeof(set));
1108 if (error) {
1109 td->td_retval[0] = error;
1110 return (0);
1111 }
1112
1113 error = kern_sigtimedwait(td, set, &ksi, NULL);
1114 if (error) {
1115 if (error == ERESTART)
1116 return (error);
1117 td->td_retval[0] = error;
1118 return (0);
1119 }
1120
1121 error = copyout(&ksi.ksi_signo, uap->sig, sizeof(ksi.ksi_signo));
1122 td->td_retval[0] = error;
1123 return (0);
1124}
1125
1126int
1127sigtimedwait(struct thread *td, struct sigtimedwait_args *uap)
1128{
1129 struct timespec ts;
1130 struct timespec *timeout;
1131 sigset_t set;
1132 ksiginfo_t ksi;
1133 int error;
1134
1135 if (uap->timeout) {
1136 error = copyin(uap->timeout, &ts, sizeof(ts));
1137 if (error)
1138 return (error);
1139
1140 timeout = &ts;
1141 } else
1142 timeout = NULL;
1143
1144 error = copyin(uap->set, &set, sizeof(set));
1145 if (error)
1146 return (error);
1147
1148 error = kern_sigtimedwait(td, set, &ksi, timeout);
1149 if (error)
1150 return (error);
1151
1152 if (uap->info)
1153 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1154
1155 if (error == 0)
1156 td->td_retval[0] = ksi.ksi_signo;
1157 return (error);
1158}
1159
1160int
1161sigwaitinfo(struct thread *td, struct sigwaitinfo_args *uap)
1162{
1163 ksiginfo_t ksi;
1164 sigset_t set;
1165 int error;
1166
1167 error = copyin(uap->set, &set, sizeof(set));
1168 if (error)
1169 return (error);
1170
1171 error = kern_sigtimedwait(td, set, &ksi, NULL);
1172 if (error)
1173 return (error);
1174
1175 if (uap->info)
1176 error = copyout(&ksi.ksi_info, uap->info, sizeof(siginfo_t));
1177
1178 if (error == 0)
1179 td->td_retval[0] = ksi.ksi_signo;
1180 return (error);
1181}
1182
1183int
1184kern_sigtimedwait(struct thread *td, sigset_t waitset, ksiginfo_t *ksi,
1185 struct timespec *timeout)
1186{
1187 struct sigacts *ps;
1188 sigset_t savedmask;
1189 struct proc *p;
1190 int error, sig, hz, i, timevalid = 0;
1191 struct timespec rts, ets, ts;
1192 struct timeval tv;
1193
1194 p = td->td_proc;
1195 error = 0;
1196 sig = 0;
1197 ets.tv_sec = 0;
1198 ets.tv_nsec = 0;
1199 SIG_CANTMASK(waitset);
1200
1201 PROC_LOCK(p);
1202 ps = p->p_sigacts;
1203 savedmask = td->td_sigmask;
1204 if (timeout) {
1205 if (timeout->tv_nsec >= 0 && timeout->tv_nsec < 1000000000) {
1206 timevalid = 1;
1207 getnanouptime(&rts);
1208 ets = rts;
1209 timespecadd(&ets, timeout);
1210 }
1211 }
1212
1213restart:
1214 for (i = 1; i <= _SIG_MAXSIG; ++i) {
1215 if (!SIGISMEMBER(waitset, i))
1216 continue;
1217 if (!SIGISMEMBER(td->td_sigqueue.sq_signals, i)) {
1218 if (SIGISMEMBER(p->p_sigqueue.sq_signals, i)) {
1219 sigqueue_move(&p->p_sigqueue,
1220 &td->td_sigqueue, i);
1221 } else
1222 continue;
1223 }
1224
1225 SIGFILLSET(td->td_sigmask);
1226 SIG_CANTMASK(td->td_sigmask);
1227 SIGDELSET(td->td_sigmask, i);
1228 mtx_lock(&ps->ps_mtx);
1229 sig = cursig(td, SIG_STOP_ALLOWED);
1230 mtx_unlock(&ps->ps_mtx);
1231 if (sig)
1232 goto out;
1233 else {
1234 /*
1235 * Because cursig() may have stopped current thread,
1236 * after it is resumed, things may have already been
1237 * changed, it should rescan any pending signals.
1238 */
1239 goto restart;
1240 }
1241 }
1242
1243 if (error)
1244 goto out;
1245
1246 /*
1247 * POSIX says this must be checked after looking for pending
1248 * signals.
1249 */
1250 if (timeout) {
1251 if (!timevalid) {
1252 error = EINVAL;
1253 goto out;
1254 }
1255 getnanouptime(&rts);
1256 if (timespeccmp(&rts, &ets, >=)) {
1257 error = EAGAIN;
1258 goto out;
1259 }
1260 ts = ets;
1261 timespecsub(&ts, &rts);
1262 TIMESPEC_TO_TIMEVAL(&tv, &ts);
1263 hz = tvtohz(&tv);
1264 } else
1265 hz = 0;
1266
1267 td->td_sigmask = savedmask;
1268 SIGSETNAND(td->td_sigmask, waitset);
1269 signotify(td);
1270 error = msleep(&ps, &p->p_mtx, PPAUSE|PCATCH, "sigwait", hz);
1271 if (timeout) {
1272 if (error == ERESTART) {
1273 /* timeout can not be restarted. */
1274 error = EINTR;
1275 } else if (error == EAGAIN) {
1276 /* will calculate timeout by ourself. */
1277 error = 0;
1278 }
1279 }
1280 goto restart;
1281
1282out:
1283 td->td_sigmask = savedmask;
1284 signotify(td);
1285 if (sig) {
1286 ksiginfo_init(ksi);
1287 sigqueue_get(&td->td_sigqueue, sig, ksi);
1288 ksi->ksi_signo = sig;
1289
1290 SDT_PROBE(proc, kernel, , signal_clear, sig, ksi, 0, 0, 0);
1291
1292 if (ksi->ksi_code == SI_TIMER)
1293 itimer_accept(p, ksi->ksi_timerid, ksi);
1294 error = 0;
1295
1296#ifdef KTRACE
1297 if (KTRPOINT(td, KTR_PSIG)) {
1298 sig_t action;
1299
1300 mtx_lock(&ps->ps_mtx);
1301 action = ps->ps_sigact[_SIG_IDX(sig)];
1302 mtx_unlock(&ps->ps_mtx);
1303 ktrpsig(sig, action, &td->td_sigmask, 0);
1304 }
1305#endif
1306 if (sig == SIGKILL)
1307 sigexit(td, sig);
1308 }
1309 PROC_UNLOCK(p);
1310 return (error);
1311}
1312
1313#ifndef _SYS_SYSPROTO_H_
1314struct sigpending_args {
1315 sigset_t *set;
1316};
1317#endif
1318int
1319sigpending(td, uap)
1320 struct thread *td;
1321 struct sigpending_args *uap;
1322{
1323 struct proc *p = td->td_proc;
1324 sigset_t pending;
1325
1326 PROC_LOCK(p);
1327 pending = p->p_sigqueue.sq_signals;
1328 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1329 PROC_UNLOCK(p);
1330 return (copyout(&pending, uap->set, sizeof(sigset_t)));
1331}
1332
1333#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1334#ifndef _SYS_SYSPROTO_H_
1335struct osigpending_args {
1336 int dummy;
1337};
1338#endif
1339int
1340osigpending(td, uap)
1341 struct thread *td;
1342 struct osigpending_args *uap;
1343{
1344 struct proc *p = td->td_proc;
1345 sigset_t pending;
1346
1347 PROC_LOCK(p);
1348 pending = p->p_sigqueue.sq_signals;
1349 SIGSETOR(pending, td->td_sigqueue.sq_signals);
1350 PROC_UNLOCK(p);
1351 SIG2OSIG(pending, td->td_retval[0]);
1352 return (0);
1353}
1354#endif /* COMPAT_43 */
1355
1356#if defined(COMPAT_43)
1357/*
1358 * Generalized interface signal handler, 4.3-compatible.
1359 */
1360#ifndef _SYS_SYSPROTO_H_
1361struct osigvec_args {
1362 int signum;
1363 struct sigvec *nsv;
1364 struct sigvec *osv;
1365};
1366#endif
1367/* ARGSUSED */
1368int
1369osigvec(td, uap)
1370 struct thread *td;
1371 register struct osigvec_args *uap;
1372{
1373 struct sigvec vec;
1374 struct sigaction nsa, osa;
1375 register struct sigaction *nsap, *osap;
1376 int error;
1377
1378 if (uap->signum <= 0 || uap->signum >= ONSIG)
1379 return (EINVAL);
1380 nsap = (uap->nsv != NULL) ? &nsa : NULL;
1381 osap = (uap->osv != NULL) ? &osa : NULL;
1382 if (nsap) {
1383 error = copyin(uap->nsv, &vec, sizeof(vec));
1384 if (error)
1385 return (error);
1386 nsap->sa_handler = vec.sv_handler;
1387 OSIG2SIG(vec.sv_mask, nsap->sa_mask);
1388 nsap->sa_flags = vec.sv_flags;
1389 nsap->sa_flags ^= SA_RESTART; /* opposite of SV_INTERRUPT */
1390 }
1391 error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
1392 if (osap && !error) {
1393 vec.sv_handler = osap->sa_handler;
1394 SIG2OSIG(osap->sa_mask, vec.sv_mask);
1395 vec.sv_flags = osap->sa_flags;
1396 vec.sv_flags &= ~SA_NOCLDWAIT;
1397 vec.sv_flags ^= SA_RESTART;
1398 error = copyout(&vec, uap->osv, sizeof(vec));
1399 }
1400 return (error);
1401}
1402
1403#ifndef _SYS_SYSPROTO_H_
1404struct osigblock_args {
1405 int mask;
1406};
1407#endif
1408int
1409osigblock(td, uap)
1410 register struct thread *td;
1411 struct osigblock_args *uap;
1412{
1413 sigset_t set, oset;
1414
1415 OSIG2SIG(uap->mask, set);
1416 kern_sigprocmask(td, SIG_BLOCK, &set, &oset, 0);
1417 SIG2OSIG(oset, td->td_retval[0]);
1418 return (0);
1419}
1420
1421#ifndef _SYS_SYSPROTO_H_
1422struct osigsetmask_args {
1423 int mask;
1424};
1425#endif
1426int
1427osigsetmask(td, uap)
1428 struct thread *td;
1429 struct osigsetmask_args *uap;
1430{
1431 sigset_t set, oset;
1432
1433 OSIG2SIG(uap->mask, set);
1434 kern_sigprocmask(td, SIG_SETMASK, &set, &oset, 0);
1435 SIG2OSIG(oset, td->td_retval[0]);
1436 return (0);
1437}
1438#endif /* COMPAT_43 */
1439
1440/*
1441 * Suspend calling thread until signal, providing mask to be set in the
1442 * meantime.
1443 */
1444#ifndef _SYS_SYSPROTO_H_
1445struct sigsuspend_args {
1446 const sigset_t *sigmask;
1447};
1448#endif
1449/* ARGSUSED */
1450int
1451sigsuspend(td, uap)
1452 struct thread *td;
1453 struct sigsuspend_args *uap;
1454{
1455 sigset_t mask;
1456 int error;
1457
1458 error = copyin(uap->sigmask, &mask, sizeof(mask));
1459 if (error)
1460 return (error);
1461 return (kern_sigsuspend(td, mask));
1462}
1463
1464int
1465kern_sigsuspend(struct thread *td, sigset_t mask)
1466{
1467 struct proc *p = td->td_proc;
1468 int has_sig, sig;
1469
1470 /*
1471 * When returning from sigsuspend, we want
1472 * the old mask to be restored after the
1473 * signal handler has finished. Thus, we
1474 * save it here and mark the sigacts structure
1475 * to indicate this.
1476 */
1477 PROC_LOCK(p);
1478 kern_sigprocmask(td, SIG_SETMASK, &mask, &td->td_oldsigmask,
1479 SIGPROCMASK_PROC_LOCKED);
1480 td->td_pflags |= TDP_OLDMASK;
1481
1482 /*
1483 * Process signals now. Otherwise, we can get spurious wakeup
1484 * due to signal entered process queue, but delivered to other
1485 * thread. But sigsuspend should return only on signal
1486 * delivery.
1487 */
1488 (p->p_sysent->sv_set_syscall_retval)(td, EINTR);
1489 for (has_sig = 0; !has_sig;) {
1490 while (msleep(&p->p_sigacts, &p->p_mtx, PPAUSE|PCATCH, "pause",
1491 0) == 0)
1492 /* void */;
1493 thread_suspend_check(0);
1494 mtx_lock(&p->p_sigacts->ps_mtx);
1495 while ((sig = cursig(td, SIG_STOP_ALLOWED)) != 0)
1496 has_sig += postsig(sig);
1497 mtx_unlock(&p->p_sigacts->ps_mtx);
1498 }
1499 PROC_UNLOCK(p);
1500 return (EJUSTRETURN);
1501}
1502
1503#ifdef COMPAT_43 /* XXX - COMPAT_FBSD3 */
1504/*
1505 * Compatibility sigsuspend call for old binaries. Note nonstandard calling
1506 * convention: libc stub passes mask, not pointer, to save a copyin.
1507 */
1508#ifndef _SYS_SYSPROTO_H_
1509struct osigsuspend_args {
1510 osigset_t mask;
1511};
1512#endif
1513/* ARGSUSED */
1514int
1515osigsuspend(td, uap)
1516 struct thread *td;
1517 struct osigsuspend_args *uap;
1518{
1519 sigset_t mask;
1520
1521 OSIG2SIG(uap->mask, mask);
1522 return (kern_sigsuspend(td, mask));
1523}
1524#endif /* COMPAT_43 */
1525
1526#if defined(COMPAT_43)
1527#ifndef _SYS_SYSPROTO_H_
1528struct osigstack_args {
1529 struct sigstack *nss;
1530 struct sigstack *oss;
1531};
1532#endif
1533/* ARGSUSED */
1534int
1535osigstack(td, uap)
1536 struct thread *td;
1537 register struct osigstack_args *uap;
1538{
1539 struct sigstack nss, oss;
1540 int error = 0;
1541
1542 if (uap->nss != NULL) {
1543 error = copyin(uap->nss, &nss, sizeof(nss));
1544 if (error)
1545 return (error);
1546 }
1547 oss.ss_sp = td->td_sigstk.ss_sp;
1548 oss.ss_onstack = sigonstack(cpu_getstack(td));
1549 if (uap->nss != NULL) {
1550 td->td_sigstk.ss_sp = nss.ss_sp;
1551 td->td_sigstk.ss_size = 0;
1552 td->td_sigstk.ss_flags |= nss.ss_onstack & SS_ONSTACK;
1553 td->td_pflags |= TDP_ALTSTACK;
1554 }
1555 if (uap->oss != NULL)
1556 error = copyout(&oss, uap->oss, sizeof(oss));
1557
1558 return (error);
1559}
1560#endif /* COMPAT_43 */
1561
1562#ifndef _SYS_SYSPROTO_H_
1563struct sigaltstack_args {
1564 stack_t *ss;
1565 stack_t *oss;
1566};
1567#endif
1568/* ARGSUSED */
1569int
1570sigaltstack(td, uap)
1571 struct thread *td;
1572 register struct sigaltstack_args *uap;
1573{
1574 stack_t ss, oss;
1575 int error;
1576
1577 if (uap->ss != NULL) {
1578 error = copyin(uap->ss, &ss, sizeof(ss));
1579 if (error)
1580 return (error);
1581 }
1582 error = kern_sigaltstack(td, (uap->ss != NULL) ? &ss : NULL,
1583 (uap->oss != NULL) ? &oss : NULL);
1584 if (error)
1585 return (error);
1586 if (uap->oss != NULL)
1587 error = copyout(&oss, uap->oss, sizeof(stack_t));
1588 return (error);
1589}
1590
1591int
1592kern_sigaltstack(struct thread *td, stack_t *ss, stack_t *oss)
1593{
1594 struct proc *p = td->td_proc;
1595 int oonstack;
1596
1597 oonstack = sigonstack(cpu_getstack(td));
1598
1599 if (oss != NULL) {
1600 *oss = td->td_sigstk;
1601 oss->ss_flags = (td->td_pflags & TDP_ALTSTACK)
1602 ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
1603 }
1604
1605 if (ss != NULL) {
1606 if (oonstack)
1607 return (EPERM);
1608 if ((ss->ss_flags & ~SS_DISABLE) != 0)
1609 return (EINVAL);
1610 if (!(ss->ss_flags & SS_DISABLE)) {
1611 if (ss->ss_size < p->p_sysent->sv_minsigstksz)
1612 return (ENOMEM);
1613
1614 td->td_sigstk = *ss;
1615 td->td_pflags |= TDP_ALTSTACK;
1616 } else {
1617 td->td_pflags &= ~TDP_ALTSTACK;
1618 }
1619 }
1620 return (0);
1621}
1622
1623/*
1624 * Common code for kill process group/broadcast kill.
1625 * cp is calling process.
1626 */
1627static int
1628killpg1(struct thread *td, int sig, int pgid, int all, ksiginfo_t *ksi)
1629{
1630 struct proc *p;
1631 struct pgrp *pgrp;
1632 int nfound = 0;
1633
1634 if (all) {
1635 /*
1636 * broadcast
1637 */
1638 sx_slock(&allproc_lock);
1639 FOREACH_PROC_IN_SYSTEM(p) {
1640 PROC_LOCK(p);
1641 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1642 p == td->td_proc || p->p_state == PRS_NEW) {
1643 PROC_UNLOCK(p);
1644 continue;
1645 }
1646 if (p_cansignal(td, p, sig) == 0) {
1647 nfound++;
1648 if (sig)
1649 pksignal(p, sig, ksi);
1650 }
1651 PROC_UNLOCK(p);
1652 }
1653 sx_sunlock(&allproc_lock);
1654 } else {
1655 sx_slock(&proctree_lock);
1656 if (pgid == 0) {
1657 /*
1658 * zero pgid means send to my process group.
1659 */
1660 pgrp = td->td_proc->p_pgrp;
1661 PGRP_LOCK(pgrp);
1662 } else {
1663 pgrp = pgfind(pgid);
1664 if (pgrp == NULL) {
1665 sx_sunlock(&proctree_lock);
1666 return (ESRCH);
1667 }
1668 }
1669 sx_sunlock(&proctree_lock);
1670 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1671 PROC_LOCK(p);
1672 if (p->p_pid <= 1 || p->p_flag & P_SYSTEM ||
1673 p->p_state == PRS_NEW ) {
1674 PROC_UNLOCK(p);
1675 continue;
1676 }
1677 if (p_cansignal(td, p, sig) == 0) {
1678 nfound++;
1679 if (sig)
1680 pksignal(p, sig, ksi);
1681 }
1682 PROC_UNLOCK(p);
1683 }
1684 PGRP_UNLOCK(pgrp);
1685 }
1686 return (nfound ? 0 : ESRCH);
1687}
1688
1689#ifndef _SYS_SYSPROTO_H_
1690struct kill_args {
1691 int pid;
1692 int signum;
1693};
1694#endif
1695/* ARGSUSED */
1696int
1697kill(struct thread *td, struct kill_args *uap)
1698{
1699 ksiginfo_t ksi;
1700 struct proc *p;
1701 int error;
1702
1703 AUDIT_ARG_SIGNUM(uap->signum);
1704 AUDIT_ARG_PID(uap->pid);
1705 if ((u_int)uap->signum > _SIG_MAXSIG)
1706 return (EINVAL);
1707
1708 ksiginfo_init(&ksi);
1709 ksi.ksi_signo = uap->signum;
1710 ksi.ksi_code = SI_USER;
1711 ksi.ksi_pid = td->td_proc->p_pid;
1712 ksi.ksi_uid = td->td_ucred->cr_ruid;
1713
1714 if (uap->pid > 0) {
1715 /* kill single process */
1716 if ((p = pfind(uap->pid)) == NULL) {
1717 if ((p = zpfind(uap->pid)) == NULL)
1718 return (ESRCH);
1719 }
1720 AUDIT_ARG_PROCESS(p);
1721 error = p_cansignal(td, p, uap->signum);
1722 if (error == 0 && uap->signum)
1723 pksignal(p, uap->signum, &ksi);
1724 PROC_UNLOCK(p);
1725 return (error);
1726 }
1727 switch (uap->pid) {
1728 case -1: /* broadcast signal */
1729 return (killpg1(td, uap->signum, 0, 1, &ksi));
1730 case 0: /* signal own process group */
1731 return (killpg1(td, uap->signum, 0, 0, &ksi));
1732 default: /* negative explicit process group */
1733 return (killpg1(td, uap->signum, -uap->pid, 0, &ksi));
1734 }
1735 /* NOTREACHED */
1736}
1737
1738#if defined(COMPAT_43)
1739#ifndef _SYS_SYSPROTO_H_
1740struct okillpg_args {
1741 int pgid;
1742 int signum;
1743};
1744#endif
1745/* ARGSUSED */
1746int
1747okillpg(struct thread *td, struct okillpg_args *uap)
1748{
1749 ksiginfo_t ksi;
1750
1751 AUDIT_ARG_SIGNUM(uap->signum);
1752 AUDIT_ARG_PID(uap->pgid);
1753 if ((u_int)uap->signum > _SIG_MAXSIG)
1754 return (EINVAL);
1755
1756 ksiginfo_init(&ksi);
1757 ksi.ksi_signo = uap->signum;
1758 ksi.ksi_code = SI_USER;
1759 ksi.ksi_pid = td->td_proc->p_pid;
1760 ksi.ksi_uid = td->td_ucred->cr_ruid;
1761 return (killpg1(td, uap->signum, uap->pgid, 0, &ksi));
1762}
1763#endif /* COMPAT_43 */
1764
1765#ifndef _SYS_SYSPROTO_H_
1766struct sigqueue_args {
1767 pid_t pid;
1768 int signum;
1769 /* union sigval */ void *value;
1770};
1771#endif
1772int
1773sigqueue(struct thread *td, struct sigqueue_args *uap)
1774{
1775 ksiginfo_t ksi;
1776 struct proc *p;
1777 int error;
1778
1779 if ((u_int)uap->signum > _SIG_MAXSIG)
1780 return (EINVAL);
1781
1782 /*
1783 * Specification says sigqueue can only send signal to
1784 * single process.
1785 */
1786 if (uap->pid <= 0)
1787 return (EINVAL);
1788
1789 if ((p = pfind(uap->pid)) == NULL) {
1790 if ((p = zpfind(uap->pid)) == NULL)
1791 return (ESRCH);
1792 }
1793 error = p_cansignal(td, p, uap->signum);
1794 if (error == 0 && uap->signum != 0) {
1795 ksiginfo_init(&ksi);
1796 ksi.ksi_flags = KSI_SIGQ;
1797 ksi.ksi_signo = uap->signum;
1798 ksi.ksi_code = SI_QUEUE;
1799 ksi.ksi_pid = td->td_proc->p_pid;
1800 ksi.ksi_uid = td->td_ucred->cr_ruid;
1801 ksi.ksi_value.sival_ptr = uap->value;
1802 error = pksignal(p, ksi.ksi_signo, &ksi);
1803 }
1804 PROC_UNLOCK(p);
1805 return (error);
1806}
1807
1808/*
1809 * Send a signal to a process group.
1810 */
1811void
1812gsignal(int pgid, int sig, ksiginfo_t *ksi)
1813{
1814 struct pgrp *pgrp;
1815
1816 if (pgid != 0) {
1817 sx_slock(&proctree_lock);
1818 pgrp = pgfind(pgid);
1819 sx_sunlock(&proctree_lock);
1820 if (pgrp != NULL) {
1821 pgsignal(pgrp, sig, 0, ksi);
1822 PGRP_UNLOCK(pgrp);
1823 }
1824 }
1825}
1826
1827/*
1828 * Send a signal to a process group. If checktty is 1,
1829 * limit to members which have a controlling terminal.
1830 */
1831void
1832pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi)
1833{
1834 struct proc *p;
1835
1836 if (pgrp) {
1837 PGRP_LOCK_ASSERT(pgrp, MA_OWNED);
1838 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1839 PROC_LOCK(p);
1840 if (checkctty == 0 || p->p_flag & P_CONTROLT)
1841 pksignal(p, sig, ksi);
1842 PROC_UNLOCK(p);
1843 }
1844 }
1845}
1846
1847/*
1848 * Send a signal caused by a trap to the current thread. If it will be
1849 * caught immediately, deliver it with correct code. Otherwise, post it
1850 * normally.
1851 */
1852void
1853trapsignal(struct thread *td, ksiginfo_t *ksi)
1854{
1855 struct sigacts *ps;
1856 sigset_t mask;
1857 struct proc *p;
1858 int sig;
1859 int code;
1860
1861 p = td->td_proc;
1862 sig = ksi->ksi_signo;
1863 code = ksi->ksi_code;
1864 KASSERT(_SIG_VALID(sig), ("invalid signal"));
1865
1866 PROC_LOCK(p);
1867 ps = p->p_sigacts;
1868 mtx_lock(&ps->ps_mtx);
1869 if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(ps->ps_sigcatch, sig) &&
1870 !SIGISMEMBER(td->td_sigmask, sig)) {
1871 td->td_ru.ru_nsignals++;
1872#ifdef KTRACE
1873 if (KTRPOINT(curthread, KTR_PSIG))
1874 ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
1875 &td->td_sigmask, code);
1876#endif
1877 (*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)],
1878 ksi, &td->td_sigmask);
1879 mask = ps->ps_catchmask[_SIG_IDX(sig)];
1880 if (!SIGISMEMBER(ps->ps_signodefer, sig))
1881 SIGADDSET(mask, sig);
1882 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
1883 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
1884 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
1885 /*
1886 * See kern_sigaction() for origin of this code.
1887 */
1888 SIGDELSET(ps->ps_sigcatch, sig);
1889 if (sig != SIGCONT &&
1890 sigprop(sig) & SA_IGNORE)
1891 SIGADDSET(ps->ps_sigignore, sig);
1892 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1893 }
1894 mtx_unlock(&ps->ps_mtx);
1895 } else {
1896 /*
1897 * Avoid a possible infinite loop if the thread
1898 * masking the signal or process is ignoring the
1899 * signal.
1900 */
1901 if (kern_forcesigexit &&
1902 (SIGISMEMBER(td->td_sigmask, sig) ||
1903 ps->ps_sigact[_SIG_IDX(sig)] == SIG_IGN)) {
1904 SIGDELSET(td->td_sigmask, sig);
1905 SIGDELSET(ps->ps_sigcatch, sig);
1906 SIGDELSET(ps->ps_sigignore, sig);
1907 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
1908 }
1909 mtx_unlock(&ps->ps_mtx);
1910 p->p_code = code; /* XXX for core dump/debugger */
1911 p->p_sig = sig; /* XXX to verify code */
1912 tdsendsignal(p, td, sig, ksi);
1913 }
1914 PROC_UNLOCK(p);
1915}
1916
1917static struct thread *
1918sigtd(struct proc *p, int sig, int prop)
1919{
1920 struct thread *td, *signal_td;
1921
1922 PROC_LOCK_ASSERT(p, MA_OWNED);
1923
1924 /*
1925 * Check if current thread can handle the signal without
1926 * switching context to another thread.
1927 */
1928 if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig))
1929 return (curthread);
1930 signal_td = NULL;
1931 FOREACH_THREAD_IN_PROC(p, td) {
1932 if (!SIGISMEMBER(td->td_sigmask, sig)) {
1933 signal_td = td;
1934 break;
1935 }
1936 }
1937 if (signal_td == NULL)
1938 signal_td = FIRST_THREAD_IN_PROC(p);
1939 return (signal_td);
1940}
1941
1942/*
1943 * Send the signal to the process. If the signal has an action, the action
1944 * is usually performed by the target process rather than the caller; we add
1945 * the signal to the set of pending signals for the process.
1946 *
1947 * Exceptions:
1948 * o When a stop signal is sent to a sleeping process that takes the
1949 * default action, the process is stopped without awakening it.
1950 * o SIGCONT restarts stopped processes (or puts them back to sleep)
1951 * regardless of the signal action (eg, blocked or ignored).
1952 *
1953 * Other ignored signals are discarded immediately.
1954 *
1955 * NB: This function may be entered from the debugger via the "kill" DDB
1956 * command. There is little that can be done to mitigate the possibly messy
1957 * side effects of this unwise possibility.
1958 */
1959void
1960psignal(struct proc *p, int sig)
1961{
1962 ksiginfo_t ksi;
1963
1964 ksiginfo_init(&ksi);
1965 ksi.ksi_signo = sig;
1966 ksi.ksi_code = SI_KERNEL;
1967 (void) tdsendsignal(p, NULL, sig, &ksi);
1968}
1969
1970int
1971pksignal(struct proc *p, int sig, ksiginfo_t *ksi)
1972{
1973
1974 return (tdsendsignal(p, NULL, sig, ksi));
1975}
1976
1977int
1978psignal_event(struct proc *p, struct sigevent *sigev, ksiginfo_t *ksi)
1979{
1980 struct thread *td = NULL;
1981
1982 PROC_LOCK_ASSERT(p, MA_OWNED);
1983
1984 KASSERT(!KSI_ONQ(ksi), ("psignal_event: ksi on queue"));
1985
1986 /*
1987 * ksi_code and other fields should be set before
1988 * calling this function.
1989 */
1990 ksi->ksi_signo = sigev->sigev_signo;
1991 ksi->ksi_value = sigev->sigev_value;
1992 if (sigev->sigev_notify == SIGEV_THREAD_ID) {
1993 td = thread_find(p, sigev->sigev_notify_thread_id);
1994 if (td == NULL)
1995 return (ESRCH);
1996 }
1997 return (tdsendsignal(p, td, ksi->ksi_signo, ksi));
1998}
1999
2000void
2001tdsignal(struct thread *td, int sig)
2002{
2003 ksiginfo_t ksi;
2004
2005 ksiginfo_init(&ksi);
2006 ksi.ksi_signo = sig;
2007 ksi.ksi_code = SI_KERNEL;
2008 (void) tdsendsignal(td->td_proc, td, sig, &ksi);
2009}
2010
2011void
2012tdksignal(struct thread *td, int sig, ksiginfo_t *ksi)
2013{
2014
2015 (void) tdsendsignal(td->td_proc, td, sig, ksi);
2016}
2017
2018static int
2019tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
2020{
2021 sig_t action;
2022 sigqueue_t *sigqueue;
2023 int prop;
2024 struct sigacts *ps;
2025 int intrval;
2026 int ret = 0;
2027 int wakeup_swapper;
2028
2029 PROC_LOCK_ASSERT(p, MA_OWNED);
2030
2031 if (!_SIG_VALID(sig))
2032 panic("tdsignal(): invalid signal %d", sig);
2033
2034 KASSERT(ksi == NULL || !KSI_ONQ(ksi), ("tdsignal: ksi on queue"));
2035
2036 /*
2037 * IEEE Std 1003.1-2001: return success when killing a zombie.
2038 */
2039 if (p->p_state == PRS_ZOMBIE) {
2040 if (ksi && (ksi->ksi_flags & KSI_INS))
2041 ksiginfo_tryfree(ksi);
2042 return (ret);
2043 }
2044
2045 ps = p->p_sigacts;
2046 KNOTE_LOCKED(&p->p_klist, NOTE_SIGNAL | sig);
2047 prop = sigprop(sig);
2048
2049 if (td == NULL) {
2050 td = sigtd(p, sig, prop);
2051 sigqueue = &p->p_sigqueue;
2052 } else {
2053 KASSERT(td->td_proc == p, ("invalid thread"));
2054 sigqueue = &td->td_sigqueue;
2055 }
2056
2057 SDT_PROBE(proc, kernel, , signal_send, td, p, sig, 0, 0 );
2058
2059 /*
2060 * If the signal is being ignored,
2061 * then we forget about it immediately.
2062 * (Note: we don't set SIGCONT in ps_sigignore,
2063 * and if it is set to SIG_IGN,
2064 * action will be SIG_DFL here.)
2065 */
2066 mtx_lock(&ps->ps_mtx);
2067 if (SIGISMEMBER(ps->ps_sigignore, sig)) {
2068 SDT_PROBE(proc, kernel, , signal_discard, ps, td, sig, 0, 0 );
2069
2070 mtx_unlock(&ps->ps_mtx);
2071 if (ksi && (ksi->ksi_flags & KSI_INS))
2072 ksiginfo_tryfree(ksi);
2073 return (ret);
2074 }
2075 if (SIGISMEMBER(td->td_sigmask, sig))
2076 action = SIG_HOLD;
2077 else if (SIGISMEMBER(ps->ps_sigcatch, sig))
2078 action = SIG_CATCH;
2079 else
2080 action = SIG_DFL;
2081 if (SIGISMEMBER(ps->ps_sigintr, sig))
2082 intrval = EINTR;
2083 else
2084 intrval = ERESTART;
2085 mtx_unlock(&ps->ps_mtx);
2086
2087 if (prop & SA_CONT)
2088 sigqueue_delete_stopmask_proc(p);
2089 else if (prop & SA_STOP) {
2090 /*
2091 * If sending a tty stop signal to a member of an orphaned
2092 * process group, discard the signal here if the action
2093 * is default; don't stop the process below if sleeping,
2094 * and don't clear any pending SIGCONT.
2095 */
2096 if ((prop & SA_TTYSTOP) &&
2097 (p->p_pgrp->pg_jobc == 0) &&
2098 (action == SIG_DFL)) {
2099 if (ksi && (ksi->ksi_flags & KSI_INS))
2100 ksiginfo_tryfree(ksi);
2101 return (ret);
2102 }
2103 sigqueue_delete_proc(p, SIGCONT);
2104 if (p->p_flag & P_CONTINUED) {
2105 p->p_flag &= ~P_CONTINUED;
2106 PROC_LOCK(p->p_pptr);
2107 sigqueue_take(p->p_ksi);
2108 PROC_UNLOCK(p->p_pptr);
2109 }
2110 }
2111
2112 ret = sigqueue_add(sigqueue, sig, ksi);
2113 if (ret != 0)
2114 return (ret);
2115 signotify(td);
2116 /*
2117 * Defer further processing for signals which are held,
2118 * except that stopped processes must be continued by SIGCONT.
2119 */
2120 if (action == SIG_HOLD &&
2121 !((prop & SA_CONT) && (p->p_flag & P_STOPPED_SIG)))
2122 return (ret);
2123 /*
2124 * SIGKILL: Remove procfs STOPEVENTs.
2125 */
2126 if (sig == SIGKILL) {
2127 /* from procfs_ioctl.c: PIOCBIC */
2128 p->p_stops = 0;
2129 /* from procfs_ioctl.c: PIOCCONT */
2130 p->p_step = 0;
2131 wakeup(&p->p_step);
2132 }
2133 /*
2134 * Some signals have a process-wide effect and a per-thread
2135 * component. Most processing occurs when the process next
2136 * tries to cross the user boundary, however there are some
2137 * times when processing needs to be done immediatly, such as
2138 * waking up threads so that they can cross the user boundary.
2139 * We try do the per-process part here.
2140 */
2141 if (P_SHOULDSTOP(p)) {
2142 /*
2143 * The process is in stopped mode. All the threads should be
2144 * either winding down or already on the suspended queue.
2145 */
2146 if (p->p_flag & P_TRACED) {
2147 /*
2148 * The traced process is already stopped,
2149 * so no further action is necessary.
2150 * No signal can restart us.
2151 */
2152 goto out;
2153 }
2154
2155 if (sig == SIGKILL) {
2156 /*
2157 * SIGKILL sets process running.
2158 * It will die elsewhere.
2159 * All threads must be restarted.
2160 */
2161 p->p_flag &= ~P_STOPPED_SIG;
2162 goto runfast;
2163 }
2164
2165 if (prop & SA_CONT) {
2166 /*
2167 * If SIGCONT is default (or ignored), we continue the
2168 * process but don't leave the signal in sigqueue as
2169 * it has no further action. If SIGCONT is held, we
2170 * continue the process and leave the signal in
2171 * sigqueue. If the process catches SIGCONT, let it
2172 * handle the signal itself. If it isn't waiting on
2173 * an event, it goes back to run state.
2174 * Otherwise, process goes back to sleep state.
2175 */
2176 p->p_flag &= ~P_STOPPED_SIG;
2177 PROC_SLOCK(p);
2178 if (p->p_numthreads == p->p_suspcount) {
2179 PROC_SUNLOCK(p);
2180 p->p_flag |= P_CONTINUED;
2181 p->p_xstat = SIGCONT;
2182 PROC_LOCK(p->p_pptr);
2183 childproc_continued(p);
2184 PROC_UNLOCK(p->p_pptr);
2185 PROC_SLOCK(p);
2186 }
2187 if (action == SIG_DFL) {
2188 thread_unsuspend(p);
2189 PROC_SUNLOCK(p);
2190 sigqueue_delete(sigqueue, sig);
2191 goto out;
2192 }
2193 if (action == SIG_CATCH) {
2194 /*
2195 * The process wants to catch it so it needs
2196 * to run at least one thread, but which one?
2197 */
2198 PROC_SUNLOCK(p);
2199 goto runfast;
2200 }
2201 /*
2202 * The signal is not ignored or caught.
2203 */
2204 thread_unsuspend(p);
2205 PROC_SUNLOCK(p);
2206 goto out;
2207 }
2208
2209 if (prop & SA_STOP) {
2210 /*
2211 * Already stopped, don't need to stop again
2212 * (If we did the shell could get confused).
2213 * Just make sure the signal STOP bit set.
2214 */
2215 p->p_flag |= P_STOPPED_SIG;
2216 sigqueue_delete(sigqueue, sig);
2217 goto out;
2218 }
2219
2220 /*
2221 * All other kinds of signals:
2222 * If a thread is sleeping interruptibly, simulate a
2223 * wakeup so that when it is continued it will be made
2224 * runnable and can look at the signal. However, don't make
2225 * the PROCESS runnable, leave it stopped.
2226 * It may run a bit until it hits a thread_suspend_check().
2227 */
2228 wakeup_swapper = 0;
2229 PROC_SLOCK(p);
2230 thread_lock(td);
2231 if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR))
2232 wakeup_swapper = sleepq_abort(td, intrval);
2233 thread_unlock(td);
2234 PROC_SUNLOCK(p);
2235 if (wakeup_swapper)
2236 kick_proc0();
2237 goto out;
2238 /*
2239 * Mutexes are short lived. Threads waiting on them will
2240 * hit thread_suspend_check() soon.
2241 */
2242 } else if (p->p_state == PRS_NORMAL) {
2243 if (p->p_flag & P_TRACED || action == SIG_CATCH) {
2244 tdsigwakeup(td, sig, action, intrval);
2245 goto out;
2246 }
2247
2248 MPASS(action == SIG_DFL);
2249
2250 if (prop & SA_STOP) {
2251 if (p->p_flag & P_PPWAIT)
2252 goto out;
2253 p->p_flag |= P_STOPPED_SIG;
2254 p->p_xstat = sig;
2255 PROC_SLOCK(p);
2256 sig_suspend_threads(td, p, 1);
2257 if (p->p_numthreads == p->p_suspcount) {
2258 /*
2259 * only thread sending signal to another
2260 * process can reach here, if thread is sending
2261 * signal to its process, because thread does
2262 * not suspend itself here, p_numthreads
2263 * should never be equal to p_suspcount.
2264 */
2265 thread_stopped(p);
2266 PROC_SUNLOCK(p);
2267 sigqueue_delete_proc(p, p->p_xstat);
2268 } else
2269 PROC_SUNLOCK(p);
2270 goto out;
2271 }
2272 } else {
2273 /* Not in "NORMAL" state. discard the signal. */
2274 sigqueue_delete(sigqueue, sig);
2275 goto out;
2276 }
2277
2278 /*
2279 * The process is not stopped so we need to apply the signal to all the
2280 * running threads.
2281 */
2282runfast:
2283 tdsigwakeup(td, sig, action, intrval);
2284 PROC_SLOCK(p);
2285 thread_unsuspend(p);
2286 PROC_SUNLOCK(p);
2287out:
2288 /* If we jump here, proc slock should not be owned. */
2289 PROC_SLOCK_ASSERT(p, MA_NOTOWNED);
2290 return (ret);
2291}
2292
2293/*
2294 * The force of a signal has been directed against a single
2295 * thread. We need to see what we can do about knocking it
2296 * out of any sleep it may be in etc.
2297 */
2298static void
2299tdsigwakeup(struct thread *td, int sig, sig_t action, int intrval)
2300{
2301 struct proc *p = td->td_proc;
2302 register int prop;
2303 int wakeup_swapper;
2304
2305 wakeup_swapper = 0;
2306 PROC_LOCK_ASSERT(p, MA_OWNED);
2307 prop = sigprop(sig);
2308
2309 PROC_SLOCK(p);
2310 thread_lock(td);
2311 /*
2312 * Bring the priority of a thread up if we want it to get
2313 * killed in this lifetime.
2314 */
2315 if (action == SIG_DFL && (prop & SA_KILL) && td->td_priority > PUSER)
2316 sched_prio(td, PUSER);
2317 if (TD_ON_SLEEPQ(td)) {
2318 /*
2319 * If thread is sleeping uninterruptibly
2320 * we can't interrupt the sleep... the signal will
2321 * be noticed when the process returns through
2322 * trap() or syscall().
2323 */
2324 if ((td->td_flags & TDF_SINTR) == 0)
2325 goto out;
2326 /*
2327 * If SIGCONT is default (or ignored) and process is
2328 * asleep, we are finished; the process should not
2329 * be awakened.
2330 */
2331 if ((prop & SA_CONT) && action == SIG_DFL) {
2332 thread_unlock(td);
2333 PROC_SUNLOCK(p);
2334 sigqueue_delete(&p->p_sigqueue, sig);
2335 /*
2336 * It may be on either list in this state.
2337 * Remove from both for now.
2338 */
2339 sigqueue_delete(&td->td_sigqueue, sig);
2340 return;
2341 }
2342
2343 /*
2344 * Give low priority threads a better chance to run.
2345 */
2346 if (td->td_priority > PUSER)
2347 sched_prio(td, PUSER);
2348
2349 wakeup_swapper = sleepq_abort(td, intrval);
2350 } else {
2351 /*
2352 * Other states do nothing with the signal immediately,
2353 * other than kicking ourselves if we are running.
2354 * It will either never be noticed, or noticed very soon.
2355 */
2356#ifdef SMP
2357 if (TD_IS_RUNNING(td) && td != curthread)
2358 forward_signal(td);
2359#endif
2360 }
2361out:
2362 PROC_SUNLOCK(p);
2363 thread_unlock(td);
2364 if (wakeup_swapper)
2365 kick_proc0();
2366}
2367
2368static void
2369sig_suspend_threads(struct thread *td, struct proc *p, int sending)
2370{
2371 struct thread *td2;
2372 int wakeup_swapper;
2373
2374 PROC_LOCK_ASSERT(p, MA_OWNED);
2375 PROC_SLOCK_ASSERT(p, MA_OWNED);
2376
2377 wakeup_swapper = 0;
2378 FOREACH_THREAD_IN_PROC(p, td2) {
2379 thread_lock(td2);
2380 td2->td_flags |= TDF_ASTPENDING | TDF_NEEDSUSPCHK;
2381 if ((TD_IS_SLEEPING(td2) || TD_IS_SWAPPED(td2)) &&
2382 (td2->td_flags & TDF_SINTR)) {
2383 if (td2->td_flags & TDF_SBDRY) {
2384 if (TD_IS_SUSPENDED(td2))
2385 wakeup_swapper |=
2386 thread_unsuspend_one(td2);
2387 if (TD_ON_SLEEPQ(td2))
2388 wakeup_swapper |=
2389 sleepq_abort(td2, ERESTART);
2390 } else if (!TD_IS_SUSPENDED(td2)) {
2391 thread_suspend_one(td2);
2392 }
2393 } else if (!TD_IS_SUSPENDED(td2)) {
2394 if (sending || td != td2)
2395 td2->td_flags |= TDF_ASTPENDING;
2396#ifdef SMP
2397 if (TD_IS_RUNNING(td2) && td2 != td)
2398 forward_signal(td2);
2399#endif
2400 }
2401 thread_unlock(td2);
2402 }
2403 if (wakeup_swapper)
2404 kick_proc0();
2405}
2406
2407int
2408ptracestop(struct thread *td, int sig)
2409{
2410 struct proc *p = td->td_proc;
2411
2412 PROC_LOCK_ASSERT(p, MA_OWNED);
2413 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2414 &p->p_mtx.lock_object, "Stopping for traced signal");
2415
2416 td->td_dbgflags |= TDB_XSIG;
2417 td->td_xsig = sig;
2418 PROC_SLOCK(p);
2419 while ((p->p_flag & P_TRACED) && (td->td_dbgflags & TDB_XSIG)) {
2420 if (p->p_flag & P_SINGLE_EXIT) {
2421 td->td_dbgflags &= ~TDB_XSIG;
2422 PROC_SUNLOCK(p);
2423 return (sig);
2424 }
2425 /*
2426 * Just make wait() to work, the last stopped thread
2427 * will win.
2428 */
2429 p->p_xstat = sig;
2430 p->p_xthread = td;
2431 p->p_flag |= (P_STOPPED_SIG|P_STOPPED_TRACE);
2432 sig_suspend_threads(td, p, 0);
2433stopme:
2434 thread_suspend_switch(td);
2435 if (!(p->p_flag & P_TRACED)) {
2436 break;
2437 }
2438 if (td->td_dbgflags & TDB_SUSPEND) {
2439 if (p->p_flag & P_SINGLE_EXIT)
2440 break;
2441 goto stopme;
2442 }
2443 }
2444 PROC_SUNLOCK(p);
2445 return (td->td_xsig);
2446}
2447
2448static void
2449reschedule_signals(struct proc *p, sigset_t block, int flags)
2450{
2451 struct sigacts *ps;
2452 struct thread *td;
2453 int i;
2454
2455 PROC_LOCK_ASSERT(p, MA_OWNED);
2456
2457 ps = p->p_sigacts;
2458 for (i = 1; !SIGISEMPTY(block); i++) {
2459 if (!SIGISMEMBER(block, i))
2460 continue;
2461 SIGDELSET(block, i);
2462 if (!SIGISMEMBER(p->p_siglist, i))
2463 continue;
2464
2465 td = sigtd(p, i, 0);
2466 signotify(td);
2467 if (!(flags & SIGPROCMASK_PS_LOCKED))
2468 mtx_lock(&ps->ps_mtx);
2469 if (p->p_flag & P_TRACED || SIGISMEMBER(ps->ps_sigcatch, i))
2470 tdsigwakeup(td, i, SIG_CATCH,
2471 (SIGISMEMBER(ps->ps_sigintr, i) ? EINTR :
2472 ERESTART));
2473 if (!(flags & SIGPROCMASK_PS_LOCKED))
2474 mtx_unlock(&ps->ps_mtx);
2475 }
2476}
2477
2478void
2479tdsigcleanup(struct thread *td)
2480{
2481 struct proc *p;
2482 sigset_t unblocked;
2483
2484 p = td->td_proc;
2485 PROC_LOCK_ASSERT(p, MA_OWNED);
2486
2487 sigqueue_flush(&td->td_sigqueue);
2488 if (p->p_numthreads == 1)
2489 return;
2490
2491 /*
2492 * Since we cannot handle signals, notify signal post code
2493 * about this by filling the sigmask.
2494 *
2495 * Also, if needed, wake up thread(s) that do not block the
2496 * same signals as the exiting thread, since the thread might
2497 * have been selected for delivery and woken up.
2498 */
2499 SIGFILLSET(unblocked);
2500 SIGSETNAND(unblocked, td->td_sigmask);
2501 SIGFILLSET(td->td_sigmask);
2502 reschedule_signals(p, unblocked, 0);
2503
2504}
2505
2506/*
2507 * If the current process has received a signal (should be caught or cause
2508 * termination, should interrupt current syscall), return the signal number.
2509 * Stop signals with default action are processed immediately, then cleared;
2510 * they aren't returned. This is checked after each entry to the system for
2511 * a syscall or trap (though this can usually be done without calling issignal
2512 * by checking the pending signal masks in cursig.) The normal call
2513 * sequence is
2514 *
2515 * while (sig = cursig(curthread))
2516 * postsig(sig);
2517 */
2518static int
2519issignal(struct thread *td, int stop_allowed)
2520{
2521 struct proc *p;
2522 struct sigacts *ps;
2523 struct sigqueue *queue;
2524 sigset_t sigpending;
|
2605 sigqueue_add(&td->td_sigqueue, sig,
2606 NULL);
2607 }
2608
2609 /*
2610 * If the traced bit got turned off, go back up
2611 * to the top to rescan signals. This ensures
2612 * that p_sig* and p_sigact are consistent.
2613 */
2614 if ((p->p_flag & P_TRACED) == 0)
2615 continue;
2616 }
2617
2618 prop = sigprop(sig);
2619
2620 /*
2621 * Decide whether the signal should be returned.
2622 * Return the signal's number, or fall through
2623 * to clear it from the pending mask.
2624 */
2625 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2626
2627 case (intptr_t)SIG_DFL:
2628 /*
2629 * Don't take default actions on system processes.
2630 */
2631 if (p->p_pid <= 1) {
2632#ifdef DIAGNOSTIC
2633 /*
2634 * Are you sure you want to ignore SIGSEGV
2635 * in init? XXX
2636 */
2637 printf("Process (pid %lu) got signal %d\n",
2638 (u_long)p->p_pid, sig);
2639#endif
2640 break; /* == ignore */
2641 }
2642 /*
2643 * If there is a pending stop signal to process
2644 * with default action, stop here,
2645 * then clear the signal. However,
2646 * if process is member of an orphaned
2647 * process group, ignore tty stop signals.
2648 */
2649 if (prop & SA_STOP) {
2650 if (p->p_flag & P_TRACED ||
2651 (p->p_pgrp->pg_jobc == 0 &&
2652 prop & SA_TTYSTOP))
2653 break; /* == ignore */
2654
2655 /* Ignore, but do not drop the stop signal. */
2656 if (stop_allowed != SIG_STOP_ALLOWED)
2657 return (sig);
2658 mtx_unlock(&ps->ps_mtx);
2659 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2660 &p->p_mtx.lock_object, "Catching SIGSTOP");
2661 p->p_flag |= P_STOPPED_SIG;
2662 p->p_xstat = sig;
2663 PROC_SLOCK(p);
2664 sig_suspend_threads(td, p, 0);
2665 thread_suspend_switch(td);
2666 PROC_SUNLOCK(p);
2667 mtx_lock(&ps->ps_mtx);
2668 break;
2669 } else if (prop & SA_IGNORE) {
2670 /*
2671 * Except for SIGCONT, shouldn't get here.
2672 * Default action is to ignore; drop it.
2673 */
2674 break; /* == ignore */
2675 } else
2676 return (sig);
2677 /*NOTREACHED*/
2678
2679 case (intptr_t)SIG_IGN:
2680 /*
2681 * Masking above should prevent us ever trying
2682 * to take action on an ignored signal other
2683 * than SIGCONT, unless process is traced.
2684 */
2685 if ((prop & SA_CONT) == 0 &&
2686 (p->p_flag & P_TRACED) == 0)
2687 printf("issignal\n");
2688 break; /* == ignore */
2689
2690 default:
2691 /*
2692 * This signal has an action, let
2693 * postsig() process it.
2694 */
2695 return (sig);
2696 }
2697 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2698 sigqueue_delete(&p->p_sigqueue, sig);
2699 }
2700 /* NOTREACHED */
2701}
2702
2703void
2704thread_stopped(struct proc *p)
2705{
2706 int n;
2707
2708 PROC_LOCK_ASSERT(p, MA_OWNED);
2709 PROC_SLOCK_ASSERT(p, MA_OWNED);
2710 n = p->p_suspcount;
2711 if (p == curproc)
2712 n++;
2713 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2714 PROC_SUNLOCK(p);
2715 p->p_flag &= ~P_WAITED;
2716 PROC_LOCK(p->p_pptr);
2717 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2718 CLD_TRAPPED : CLD_STOPPED);
2719 PROC_UNLOCK(p->p_pptr);
2720 PROC_SLOCK(p);
2721 }
2722}
2723
2724/*
2725 * Take the action for the specified signal
2726 * from the current set of pending signals.
2727 */
2728int
2729postsig(sig)
2730 register int sig;
2731{
2732 struct thread *td = curthread;
2733 register struct proc *p = td->td_proc;
2734 struct sigacts *ps;
2735 sig_t action;
2736 ksiginfo_t ksi;
2737 sigset_t returnmask, mask;
2738
2739 KASSERT(sig != 0, ("postsig"));
2740
2741 PROC_LOCK_ASSERT(p, MA_OWNED);
2742 ps = p->p_sigacts;
2743 mtx_assert(&ps->ps_mtx, MA_OWNED);
2744 ksiginfo_init(&ksi);
2745 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2746 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2747 return (0);
2748 ksi.ksi_signo = sig;
2749 if (ksi.ksi_code == SI_TIMER)
2750 itimer_accept(p, ksi.ksi_timerid, &ksi);
2751 action = ps->ps_sigact[_SIG_IDX(sig)];
2752#ifdef KTRACE
2753 if (KTRPOINT(td, KTR_PSIG))
2754 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2755 &td->td_oldsigmask : &td->td_sigmask, 0);
2756#endif
2757 if (p->p_stops & S_SIG) {
2758 mtx_unlock(&ps->ps_mtx);
2759 stopevent(p, S_SIG, sig);
2760 mtx_lock(&ps->ps_mtx);
2761 }
2762
2763 if (action == SIG_DFL) {
2764 /*
2765 * Default action, where the default is to kill
2766 * the process. (Other cases were ignored above.)
2767 */
2768 mtx_unlock(&ps->ps_mtx);
2769 sigexit(td, sig);
2770 /* NOTREACHED */
2771 } else {
2772 /*
2773 * If we get here, the signal must be caught.
2774 */
2775 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2776 ("postsig action"));
2777 /*
2778 * Set the new mask value and also defer further
2779 * occurrences of this signal.
2780 *
2781 * Special case: user has done a sigsuspend. Here the
2782 * current mask is not of interest, but rather the
2783 * mask from before the sigsuspend is what we want
2784 * restored after the signal processing is completed.
2785 */
2786 if (td->td_pflags & TDP_OLDMASK) {
2787 returnmask = td->td_oldsigmask;
2788 td->td_pflags &= ~TDP_OLDMASK;
2789 } else
2790 returnmask = td->td_sigmask;
2791
2792 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2793 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2794 SIGADDSET(mask, sig);
2795 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2796 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2797
2798 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2799 /*
2800 * See kern_sigaction() for origin of this code.
2801 */
2802 SIGDELSET(ps->ps_sigcatch, sig);
2803 if (sig != SIGCONT &&
2804 sigprop(sig) & SA_IGNORE)
2805 SIGADDSET(ps->ps_sigignore, sig);
2806 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2807 }
2808 td->td_ru.ru_nsignals++;
2809 if (p->p_sig == sig) {
2810 p->p_code = 0;
2811 p->p_sig = 0;
2812 }
2813 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2814 }
2815 return (1);
2816}
2817
2818/*
2819 * Kill the current process for stated reason.
2820 */
2821void
2822killproc(p, why)
2823 struct proc *p;
2824 char *why;
2825{
2826
2827 PROC_LOCK_ASSERT(p, MA_OWNED);
2828 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)",
2829 p, p->p_pid, p->p_comm);
2830 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
2831 p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2832 p->p_flag |= P_WKILLED;
2833 psignal(p, SIGKILL);
2834}
2835
2836/*
2837 * Force the current process to exit with the specified signal, dumping core
2838 * if appropriate. We bypass the normal tests for masked and caught signals,
2839 * allowing unrecoverable failures to terminate the process without changing
2840 * signal state. Mark the accounting record with the signal termination.
2841 * If dumping core, save the signal number for the debugger. Calls exit and
2842 * does not return.
2843 */
2844void
2845sigexit(td, sig)
2846 struct thread *td;
2847 int sig;
2848{
2849 struct proc *p = td->td_proc;
2850
2851 PROC_LOCK_ASSERT(p, MA_OWNED);
2852 p->p_acflag |= AXSIG;
2853 /*
2854 * We must be single-threading to generate a core dump. This
2855 * ensures that the registers in the core file are up-to-date.
2856 * Also, the ELF dump handler assumes that the thread list doesn't
2857 * change out from under it.
2858 *
2859 * XXX If another thread attempts to single-thread before us
2860 * (e.g. via fork()), we won't get a dump at all.
2861 */
2862 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2863 p->p_sig = sig;
2864 /*
2865 * Log signals which would cause core dumps
2866 * (Log as LOG_INFO to appease those who don't want
2867 * these messages.)
2868 * XXX : Todo, as well as euid, write out ruid too
2869 * Note that coredump() drops proc lock.
2870 */
2871 if (coredump(td) == 0)
2872 sig |= WCOREFLAG;
2873 if (kern_logsigexit)
2874 log(LOG_INFO,
2875 "pid %d (%s), uid %d: exited on signal %d%s\n",
2876 p->p_pid, p->p_comm,
2877 td->td_ucred ? td->td_ucred->cr_uid : -1,
2878 sig &~ WCOREFLAG,
2879 sig & WCOREFLAG ? " (core dumped)" : "");
2880 } else
2881 PROC_UNLOCK(p);
2882 exit1(td, W_EXITCODE(0, sig));
2883 /* NOTREACHED */
2884}
2885
2886/*
2887 * Send queued SIGCHLD to parent when child process's state
2888 * is changed.
2889 */
2890static void
2891sigparent(struct proc *p, int reason, int status)
2892{
2893 PROC_LOCK_ASSERT(p, MA_OWNED);
2894 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2895
2896 if (p->p_ksi != NULL) {
2897 p->p_ksi->ksi_signo = SIGCHLD;
2898 p->p_ksi->ksi_code = reason;
2899 p->p_ksi->ksi_status = status;
2900 p->p_ksi->ksi_pid = p->p_pid;
2901 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2902 if (KSI_ONQ(p->p_ksi))
2903 return;
2904 }
2905 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2906}
2907
2908static void
2909childproc_jobstate(struct proc *p, int reason, int status)
2910{
2911 struct sigacts *ps;
2912
2913 PROC_LOCK_ASSERT(p, MA_OWNED);
2914 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2915
2916 /*
2917 * Wake up parent sleeping in kern_wait(), also send
2918 * SIGCHLD to parent, but SIGCHLD does not guarantee
2919 * that parent will awake, because parent may masked
2920 * the signal.
2921 */
2922 p->p_pptr->p_flag |= P_STATCHILD;
2923 wakeup(p->p_pptr);
2924
2925 ps = p->p_pptr->p_sigacts;
2926 mtx_lock(&ps->ps_mtx);
2927 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2928 mtx_unlock(&ps->ps_mtx);
2929 sigparent(p, reason, status);
2930 } else
2931 mtx_unlock(&ps->ps_mtx);
2932}
2933
2934void
2935childproc_stopped(struct proc *p, int reason)
2936{
2937 childproc_jobstate(p, reason, p->p_xstat);
2938}
2939
2940void
2941childproc_continued(struct proc *p)
2942{
2943 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
2944}
2945
2946void
2947childproc_exited(struct proc *p)
2948{
2949 int reason;
2950 int status = p->p_xstat; /* convert to int */
2951
2952 reason = CLD_EXITED;
2953 if (WCOREDUMP(status))
2954 reason = CLD_DUMPED;
2955 else if (WIFSIGNALED(status))
2956 reason = CLD_KILLED;
2957 /*
2958 * XXX avoid calling wakeup(p->p_pptr), the work is
2959 * done in exit1().
2960 */
2961 sigparent(p, reason, status);
2962}
2963
2964/*
2965 * We only have 1 character for the core count in the format
2966 * string, so the range will be 0-9
2967 */
2968#define MAX_NUM_CORES 10
2969static int num_cores = 5;
2970
2971static int
2972sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
2973{
2974 int error;
2975 int new_val;
2976
2977 new_val = num_cores;
2978 error = sysctl_handle_int(oidp, &new_val, 0, req);
2979 if (error != 0 || req->newptr == NULL)
2980 return (error);
2981 if (new_val > MAX_NUM_CORES)
2982 new_val = MAX_NUM_CORES;
2983 if (new_val < 0)
2984 new_val = 0;
2985 num_cores = new_val;
2986 return (0);
2987}
2988SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
2989 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
2990
2991#if defined(COMPRESS_USER_CORES)
2992int compress_user_cores = 1;
2993SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
2994 &compress_user_cores, 0, "");
2995
2996int compress_user_cores_gzlevel = -1; /* default level */
2997SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
2998 &compress_user_cores_gzlevel, -1, "user core gz compression level");
2999
3000#define GZ_SUFFIX ".gz"
3001#define GZ_SUFFIX_LEN 3
3002#endif
3003
3004static char corefilename[MAXPATHLEN] = {"%N.core"};
3005SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3006 sizeof(corefilename), "process corefile name format string");
3007
3008/*
3009 * expand_name(name, uid, pid, td, compress)
3010 * Expand the name described in corefilename, using name, uid, and pid.
3011 * corefilename is a printf-like string, with three format specifiers:
3012 * %N name of process ("name")
3013 * %P process id (pid)
3014 * %U user id (uid)
3015 * For example, "%N.core" is the default; they can be disabled completely
3016 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3017 * This is controlled by the sysctl variable kern.corefile (see above).
3018 */
3019static char *
3020expand_name(const char *name, uid_t uid, pid_t pid, struct thread *td,
3021 int compress)
3022{
3023 struct sbuf sb;
3024 const char *format;
3025 char *temp;
3026 size_t i;
3027 int indexpos;
3028 char *hostname;
3029
3030 hostname = NULL;
3031 format = corefilename;
3032 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
3033 if (temp == NULL)
3034 return (NULL);
3035 indexpos = -1;
3036 (void)sbuf_new(&sb, temp, MAXPATHLEN, SBUF_FIXEDLEN);
3037 for (i = 0; format[i]; i++) {
3038 switch (format[i]) {
3039 case '%': /* Format character */
3040 i++;
3041 switch (format[i]) {
3042 case '%':
3043 sbuf_putc(&sb, '%');
3044 break;
3045 case 'H': /* hostname */
3046 if (hostname == NULL) {
3047 hostname = malloc(MAXHOSTNAMELEN,
3048 M_TEMP, M_NOWAIT);
3049 if (hostname == NULL) {
3050 log(LOG_ERR,
3051 "pid %ld (%s), uid (%lu): "
3052 "unable to alloc memory "
3053 "for corefile hostname\n",
3054 (long)pid, name,
3055 (u_long)uid);
3056 goto nomem;
3057 }
3058 }
3059 getcredhostname(td->td_ucred, hostname,
3060 MAXHOSTNAMELEN);
3061 sbuf_printf(&sb, "%s", hostname);
3062 break;
3063 case 'I': /* autoincrementing index */
3064 sbuf_printf(&sb, "0");
3065 indexpos = sbuf_len(&sb) - 1;
3066 break;
3067 case 'N': /* process name */
3068 sbuf_printf(&sb, "%s", name);
3069 break;
3070 case 'P': /* process id */
3071 sbuf_printf(&sb, "%u", pid);
3072 break;
3073 case 'U': /* user id */
3074 sbuf_printf(&sb, "%u", uid);
3075 break;
3076 default:
3077 log(LOG_ERR,
3078 "Unknown format character %c in "
3079 "corename `%s'\n", format[i], format);
3080 }
3081 break;
3082 default:
3083 sbuf_putc(&sb, format[i]);
3084 }
3085 }
3086 free(hostname, M_TEMP);
3087#ifdef COMPRESS_USER_CORES
3088 if (compress) {
3089 sbuf_printf(&sb, GZ_SUFFIX);
3090 }
3091#endif
3092 if (sbuf_overflowed(&sb)) {
3093 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3094 "long\n", (long)pid, name, (u_long)uid);
3095nomem:
3096 sbuf_delete(&sb);
3097 free(temp, M_TEMP);
3098 return (NULL);
3099 }
3100 sbuf_finish(&sb);
3101 sbuf_delete(&sb);
3102
3103 /*
3104 * If the core format has a %I in it, then we need to check
3105 * for existing corefiles before returning a name.
3106 * To do this we iterate over 0..num_cores to find a
3107 * non-existing core file name to use.
3108 */
3109 if (indexpos != -1) {
3110 struct nameidata nd;
3111 int error, n;
3112 int flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3113 int cmode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
3114 int vfslocked;
3115
3116 for (n = 0; n < num_cores; n++) {
3117 temp[indexpos] = '0' + n;
3118 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE,
3119 temp, td);
3120 error = vn_open(&nd, &flags, cmode, NULL);
3121 if (error) {
3122 if (error == EEXIST) {
3123 continue;
3124 }
3125 log(LOG_ERR,
3126 "pid %d (%s), uid (%u): Path `%s' failed "
3127 "on initial open test, error = %d\n",
3128 pid, name, uid, temp, error);
3129 free(temp, M_TEMP);
3130 return (NULL);
3131 }
3132 vfslocked = NDHASGIANT(&nd);
3133 NDFREE(&nd, NDF_ONLY_PNBUF);
3134 VOP_UNLOCK(nd.ni_vp, 0);
3135 error = vn_close(nd.ni_vp, FWRITE, td->td_ucred, td);
3136 VFS_UNLOCK_GIANT(vfslocked);
3137 if (error) {
3138 log(LOG_ERR,
3139 "pid %d (%s), uid (%u): Path `%s' failed "
3140 "on close after initial open test, "
3141 "error = %d\n",
3142 pid, name, uid, temp, error);
3143 free(temp, M_TEMP);
3144 return (NULL);
3145 }
3146 break;
3147 }
3148 }
3149 return (temp);
3150}
3151
3152/*
3153 * Dump a process' core. The main routine does some
3154 * policy checking, and creates the name of the coredump;
3155 * then it passes on a vnode and a size limit to the process-specific
3156 * coredump routine if there is one; if there _is not_ one, it returns
3157 * ENOSYS; otherwise it returns the error from the process-specific routine.
3158 */
3159
3160static int
3161coredump(struct thread *td)
3162{
3163 struct proc *p = td->td_proc;
3164 register struct vnode *vp;
3165 register struct ucred *cred = td->td_ucred;
3166 struct flock lf;
3167 struct nameidata nd;
3168 struct vattr vattr;
3169 int error, error1, flags, locked;
3170 struct mount *mp;
3171 char *name; /* name of corefile */
3172 off_t limit;
3173 int vfslocked;
3174 int compress;
3175
3176#ifdef COMPRESS_USER_CORES
3177 compress = compress_user_cores;
3178#else
3179 compress = 0;
3180#endif
3181 PROC_LOCK_ASSERT(p, MA_OWNED);
3182 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3183 _STOPEVENT(p, S_CORE, 0);
3184
3185 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid, td,
3186 compress);
3187 if (name == NULL) {
3188 PROC_UNLOCK(p);
3189#ifdef AUDIT
3190 audit_proc_coredump(td, NULL, EINVAL);
3191#endif
3192 return (EINVAL);
3193 }
3194 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) {
3195 PROC_UNLOCK(p);
3196#ifdef AUDIT
3197 audit_proc_coredump(td, name, EFAULT);
3198#endif
3199 free(name, M_TEMP);
3200 return (EFAULT);
3201 }
3202
3203 /*
3204 * Note that the bulk of limit checking is done after
3205 * the corefile is created. The exception is if the limit
3206 * for corefiles is 0, in which case we don't bother
3207 * creating the corefile at all. This layout means that
3208 * a corefile is truncated instead of not being created,
3209 * if it is larger than the limit.
3210 */
3211 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3212 PROC_UNLOCK(p);
3213 if (limit == 0) {
3214#ifdef AUDIT
3215 audit_proc_coredump(td, name, EFBIG);
3216#endif
3217 free(name, M_TEMP);
3218 return (EFBIG);
3219 }
3220
3221restart:
3222 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, name, td);
3223 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3224 error = vn_open_cred(&nd, &flags, S_IRUSR | S_IWUSR, VN_OPEN_NOAUDIT,
3225 cred, NULL);
3226 if (error) {
3227#ifdef AUDIT
3228 audit_proc_coredump(td, name, error);
3229#endif
3230 free(name, M_TEMP);
3231 return (error);
3232 }
3233 vfslocked = NDHASGIANT(&nd);
3234 NDFREE(&nd, NDF_ONLY_PNBUF);
3235 vp = nd.ni_vp;
3236
3237 /* Don't dump to non-regular files or files with links. */
3238 if (vp->v_type != VREG ||
3239 VOP_GETATTR(vp, &vattr, cred) || vattr.va_nlink != 1) {
3240 VOP_UNLOCK(vp, 0);
3241 error = EFAULT;
3242 goto close;
3243 }
3244
3245 VOP_UNLOCK(vp, 0);
3246 lf.l_whence = SEEK_SET;
3247 lf.l_start = 0;
3248 lf.l_len = 0;
3249 lf.l_type = F_WRLCK;
3250 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3251
3252 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3253 lf.l_type = F_UNLCK;
3254 if (locked)
3255 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3256 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3257 goto out;
3258 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3259 goto out;
3260 VFS_UNLOCK_GIANT(vfslocked);
3261 goto restart;
3262 }
3263
3264 VATTR_NULL(&vattr);
3265 vattr.va_size = 0;
3266 if (set_core_nodump_flag)
3267 vattr.va_flags = UF_NODUMP;
3268 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3269 VOP_SETATTR(vp, &vattr, cred);
3270 VOP_UNLOCK(vp, 0);
3271 vn_finished_write(mp);
3272 PROC_LOCK(p);
3273 p->p_acflag |= ACORE;
3274 PROC_UNLOCK(p);
3275
3276 error = p->p_sysent->sv_coredump ?
3277 p->p_sysent->sv_coredump(td, vp, limit, compress ? IMGACT_CORE_COMPRESS : 0) :
3278 ENOSYS;
3279
3280 if (locked) {
3281 lf.l_type = F_UNLCK;
3282 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3283 }
3284close:
3285 error1 = vn_close(vp, FWRITE, cred, td);
3286 if (error == 0)
3287 error = error1;
3288out:
3289#ifdef AUDIT
3290 audit_proc_coredump(td, name, error);
3291#endif
3292 free(name, M_TEMP);
3293 VFS_UNLOCK_GIANT(vfslocked);
3294 return (error);
3295}
3296
3297/*
3298 * Nonexistent system call-- signal process (may want to handle it). Flag
3299 * error in case process won't see signal immediately (blocked or ignored).
3300 */
3301#ifndef _SYS_SYSPROTO_H_
3302struct nosys_args {
3303 int dummy;
3304};
3305#endif
3306/* ARGSUSED */
3307int
3308nosys(td, args)
3309 struct thread *td;
3310 struct nosys_args *args;
3311{
3312 struct proc *p = td->td_proc;
3313
3314 PROC_LOCK(p);
3315 psignal(p, SIGSYS);
3316 PROC_UNLOCK(p);
3317 return (ENOSYS);
3318}
3319
3320/*
3321 * Send a SIGIO or SIGURG signal to a process or process group using stored
3322 * credentials rather than those of the current process.
3323 */
3324void
3325pgsigio(sigiop, sig, checkctty)
3326 struct sigio **sigiop;
3327 int sig, checkctty;
3328{
3329 ksiginfo_t ksi;
3330 struct sigio *sigio;
3331
3332 ksiginfo_init(&ksi);
3333 ksi.ksi_signo = sig;
3334 ksi.ksi_code = SI_KERNEL;
3335
3336 SIGIO_LOCK();
3337 sigio = *sigiop;
3338 if (sigio == NULL) {
3339 SIGIO_UNLOCK();
3340 return;
3341 }
3342 if (sigio->sio_pgid > 0) {
3343 PROC_LOCK(sigio->sio_proc);
3344 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3345 psignal(sigio->sio_proc, sig);
3346 PROC_UNLOCK(sigio->sio_proc);
3347 } else if (sigio->sio_pgid < 0) {
3348 struct proc *p;
3349
3350 PGRP_LOCK(sigio->sio_pgrp);
3351 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3352 PROC_LOCK(p);
3353 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3354 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3355 psignal(p, sig);
3356 PROC_UNLOCK(p);
3357 }
3358 PGRP_UNLOCK(sigio->sio_pgrp);
3359 }
3360 SIGIO_UNLOCK();
3361}
3362
3363static int
3364filt_sigattach(struct knote *kn)
3365{
3366 struct proc *p = curproc;
3367
3368 kn->kn_ptr.p_proc = p;
3369 kn->kn_flags |= EV_CLEAR; /* automatically set */
3370
3371 knlist_add(&p->p_klist, kn, 0);
3372
3373 return (0);
3374}
3375
3376static void
3377filt_sigdetach(struct knote *kn)
3378{
3379 struct proc *p = kn->kn_ptr.p_proc;
3380
3381 knlist_remove(&p->p_klist, kn, 0);
3382}
3383
3384/*
3385 * signal knotes are shared with proc knotes, so we apply a mask to
3386 * the hint in order to differentiate them from process hints. This
3387 * could be avoided by using a signal-specific knote list, but probably
3388 * isn't worth the trouble.
3389 */
3390static int
3391filt_signal(struct knote *kn, long hint)
3392{
3393
3394 if (hint & NOTE_SIGNAL) {
3395 hint &= ~NOTE_SIGNAL;
3396
3397 if (kn->kn_id == hint)
3398 kn->kn_data++;
3399 }
3400 return (kn->kn_data != 0);
3401}
3402
3403struct sigacts *
3404sigacts_alloc(void)
3405{
3406 struct sigacts *ps;
3407
3408 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3409 ps->ps_refcnt = 1;
3410 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3411 return (ps);
3412}
3413
3414void
3415sigacts_free(struct sigacts *ps)
3416{
3417
3418 mtx_lock(&ps->ps_mtx);
3419 ps->ps_refcnt--;
3420 if (ps->ps_refcnt == 0) {
3421 mtx_destroy(&ps->ps_mtx);
3422 free(ps, M_SUBPROC);
3423 } else
3424 mtx_unlock(&ps->ps_mtx);
3425}
3426
3427struct sigacts *
3428sigacts_hold(struct sigacts *ps)
3429{
3430 mtx_lock(&ps->ps_mtx);
3431 ps->ps_refcnt++;
3432 mtx_unlock(&ps->ps_mtx);
3433 return (ps);
3434}
3435
3436void
3437sigacts_copy(struct sigacts *dest, struct sigacts *src)
3438{
3439
3440 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3441 mtx_lock(&src->ps_mtx);
3442 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3443 mtx_unlock(&src->ps_mtx);
3444}
3445
3446int
3447sigacts_shared(struct sigacts *ps)
3448{
3449 int shared;
3450
3451 mtx_lock(&ps->ps_mtx);
3452 shared = ps->ps_refcnt > 1;
3453 mtx_unlock(&ps->ps_mtx);
3454 return (shared);
3455}
| 2604 sigqueue_add(&td->td_sigqueue, sig,
2605 NULL);
2606 }
2607
2608 /*
2609 * If the traced bit got turned off, go back up
2610 * to the top to rescan signals. This ensures
2611 * that p_sig* and p_sigact are consistent.
2612 */
2613 if ((p->p_flag & P_TRACED) == 0)
2614 continue;
2615 }
2616
2617 prop = sigprop(sig);
2618
2619 /*
2620 * Decide whether the signal should be returned.
2621 * Return the signal's number, or fall through
2622 * to clear it from the pending mask.
2623 */
2624 switch ((intptr_t)p->p_sigacts->ps_sigact[_SIG_IDX(sig)]) {
2625
2626 case (intptr_t)SIG_DFL:
2627 /*
2628 * Don't take default actions on system processes.
2629 */
2630 if (p->p_pid <= 1) {
2631#ifdef DIAGNOSTIC
2632 /*
2633 * Are you sure you want to ignore SIGSEGV
2634 * in init? XXX
2635 */
2636 printf("Process (pid %lu) got signal %d\n",
2637 (u_long)p->p_pid, sig);
2638#endif
2639 break; /* == ignore */
2640 }
2641 /*
2642 * If there is a pending stop signal to process
2643 * with default action, stop here,
2644 * then clear the signal. However,
2645 * if process is member of an orphaned
2646 * process group, ignore tty stop signals.
2647 */
2648 if (prop & SA_STOP) {
2649 if (p->p_flag & P_TRACED ||
2650 (p->p_pgrp->pg_jobc == 0 &&
2651 prop & SA_TTYSTOP))
2652 break; /* == ignore */
2653
2654 /* Ignore, but do not drop the stop signal. */
2655 if (stop_allowed != SIG_STOP_ALLOWED)
2656 return (sig);
2657 mtx_unlock(&ps->ps_mtx);
2658 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK,
2659 &p->p_mtx.lock_object, "Catching SIGSTOP");
2660 p->p_flag |= P_STOPPED_SIG;
2661 p->p_xstat = sig;
2662 PROC_SLOCK(p);
2663 sig_suspend_threads(td, p, 0);
2664 thread_suspend_switch(td);
2665 PROC_SUNLOCK(p);
2666 mtx_lock(&ps->ps_mtx);
2667 break;
2668 } else if (prop & SA_IGNORE) {
2669 /*
2670 * Except for SIGCONT, shouldn't get here.
2671 * Default action is to ignore; drop it.
2672 */
2673 break; /* == ignore */
2674 } else
2675 return (sig);
2676 /*NOTREACHED*/
2677
2678 case (intptr_t)SIG_IGN:
2679 /*
2680 * Masking above should prevent us ever trying
2681 * to take action on an ignored signal other
2682 * than SIGCONT, unless process is traced.
2683 */
2684 if ((prop & SA_CONT) == 0 &&
2685 (p->p_flag & P_TRACED) == 0)
2686 printf("issignal\n");
2687 break; /* == ignore */
2688
2689 default:
2690 /*
2691 * This signal has an action, let
2692 * postsig() process it.
2693 */
2694 return (sig);
2695 }
2696 sigqueue_delete(&td->td_sigqueue, sig); /* take the signal! */
2697 sigqueue_delete(&p->p_sigqueue, sig);
2698 }
2699 /* NOTREACHED */
2700}
2701
2702void
2703thread_stopped(struct proc *p)
2704{
2705 int n;
2706
2707 PROC_LOCK_ASSERT(p, MA_OWNED);
2708 PROC_SLOCK_ASSERT(p, MA_OWNED);
2709 n = p->p_suspcount;
2710 if (p == curproc)
2711 n++;
2712 if ((p->p_flag & P_STOPPED_SIG) && (n == p->p_numthreads)) {
2713 PROC_SUNLOCK(p);
2714 p->p_flag &= ~P_WAITED;
2715 PROC_LOCK(p->p_pptr);
2716 childproc_stopped(p, (p->p_flag & P_TRACED) ?
2717 CLD_TRAPPED : CLD_STOPPED);
2718 PROC_UNLOCK(p->p_pptr);
2719 PROC_SLOCK(p);
2720 }
2721}
2722
2723/*
2724 * Take the action for the specified signal
2725 * from the current set of pending signals.
2726 */
2727int
2728postsig(sig)
2729 register int sig;
2730{
2731 struct thread *td = curthread;
2732 register struct proc *p = td->td_proc;
2733 struct sigacts *ps;
2734 sig_t action;
2735 ksiginfo_t ksi;
2736 sigset_t returnmask, mask;
2737
2738 KASSERT(sig != 0, ("postsig"));
2739
2740 PROC_LOCK_ASSERT(p, MA_OWNED);
2741 ps = p->p_sigacts;
2742 mtx_assert(&ps->ps_mtx, MA_OWNED);
2743 ksiginfo_init(&ksi);
2744 if (sigqueue_get(&td->td_sigqueue, sig, &ksi) == 0 &&
2745 sigqueue_get(&p->p_sigqueue, sig, &ksi) == 0)
2746 return (0);
2747 ksi.ksi_signo = sig;
2748 if (ksi.ksi_code == SI_TIMER)
2749 itimer_accept(p, ksi.ksi_timerid, &ksi);
2750 action = ps->ps_sigact[_SIG_IDX(sig)];
2751#ifdef KTRACE
2752 if (KTRPOINT(td, KTR_PSIG))
2753 ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
2754 &td->td_oldsigmask : &td->td_sigmask, 0);
2755#endif
2756 if (p->p_stops & S_SIG) {
2757 mtx_unlock(&ps->ps_mtx);
2758 stopevent(p, S_SIG, sig);
2759 mtx_lock(&ps->ps_mtx);
2760 }
2761
2762 if (action == SIG_DFL) {
2763 /*
2764 * Default action, where the default is to kill
2765 * the process. (Other cases were ignored above.)
2766 */
2767 mtx_unlock(&ps->ps_mtx);
2768 sigexit(td, sig);
2769 /* NOTREACHED */
2770 } else {
2771 /*
2772 * If we get here, the signal must be caught.
2773 */
2774 KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
2775 ("postsig action"));
2776 /*
2777 * Set the new mask value and also defer further
2778 * occurrences of this signal.
2779 *
2780 * Special case: user has done a sigsuspend. Here the
2781 * current mask is not of interest, but rather the
2782 * mask from before the sigsuspend is what we want
2783 * restored after the signal processing is completed.
2784 */
2785 if (td->td_pflags & TDP_OLDMASK) {
2786 returnmask = td->td_oldsigmask;
2787 td->td_pflags &= ~TDP_OLDMASK;
2788 } else
2789 returnmask = td->td_sigmask;
2790
2791 mask = ps->ps_catchmask[_SIG_IDX(sig)];
2792 if (!SIGISMEMBER(ps->ps_signodefer, sig))
2793 SIGADDSET(mask, sig);
2794 kern_sigprocmask(td, SIG_BLOCK, &mask, NULL,
2795 SIGPROCMASK_PROC_LOCKED | SIGPROCMASK_PS_LOCKED);
2796
2797 if (SIGISMEMBER(ps->ps_sigreset, sig)) {
2798 /*
2799 * See kern_sigaction() for origin of this code.
2800 */
2801 SIGDELSET(ps->ps_sigcatch, sig);
2802 if (sig != SIGCONT &&
2803 sigprop(sig) & SA_IGNORE)
2804 SIGADDSET(ps->ps_sigignore, sig);
2805 ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
2806 }
2807 td->td_ru.ru_nsignals++;
2808 if (p->p_sig == sig) {
2809 p->p_code = 0;
2810 p->p_sig = 0;
2811 }
2812 (*p->p_sysent->sv_sendsig)(action, &ksi, &returnmask);
2813 }
2814 return (1);
2815}
2816
2817/*
2818 * Kill the current process for stated reason.
2819 */
2820void
2821killproc(p, why)
2822 struct proc *p;
2823 char *why;
2824{
2825
2826 PROC_LOCK_ASSERT(p, MA_OWNED);
2827 CTR3(KTR_PROC, "killproc: proc %p (pid %d, %s)",
2828 p, p->p_pid, p->p_comm);
2829 log(LOG_ERR, "pid %d (%s), uid %d, was killed: %s\n", p->p_pid, p->p_comm,
2830 p->p_ucred ? p->p_ucred->cr_uid : -1, why);
2831 p->p_flag |= P_WKILLED;
2832 psignal(p, SIGKILL);
2833}
2834
2835/*
2836 * Force the current process to exit with the specified signal, dumping core
2837 * if appropriate. We bypass the normal tests for masked and caught signals,
2838 * allowing unrecoverable failures to terminate the process without changing
2839 * signal state. Mark the accounting record with the signal termination.
2840 * If dumping core, save the signal number for the debugger. Calls exit and
2841 * does not return.
2842 */
2843void
2844sigexit(td, sig)
2845 struct thread *td;
2846 int sig;
2847{
2848 struct proc *p = td->td_proc;
2849
2850 PROC_LOCK_ASSERT(p, MA_OWNED);
2851 p->p_acflag |= AXSIG;
2852 /*
2853 * We must be single-threading to generate a core dump. This
2854 * ensures that the registers in the core file are up-to-date.
2855 * Also, the ELF dump handler assumes that the thread list doesn't
2856 * change out from under it.
2857 *
2858 * XXX If another thread attempts to single-thread before us
2859 * (e.g. via fork()), we won't get a dump at all.
2860 */
2861 if ((sigprop(sig) & SA_CORE) && (thread_single(SINGLE_NO_EXIT) == 0)) {
2862 p->p_sig = sig;
2863 /*
2864 * Log signals which would cause core dumps
2865 * (Log as LOG_INFO to appease those who don't want
2866 * these messages.)
2867 * XXX : Todo, as well as euid, write out ruid too
2868 * Note that coredump() drops proc lock.
2869 */
2870 if (coredump(td) == 0)
2871 sig |= WCOREFLAG;
2872 if (kern_logsigexit)
2873 log(LOG_INFO,
2874 "pid %d (%s), uid %d: exited on signal %d%s\n",
2875 p->p_pid, p->p_comm,
2876 td->td_ucred ? td->td_ucred->cr_uid : -1,
2877 sig &~ WCOREFLAG,
2878 sig & WCOREFLAG ? " (core dumped)" : "");
2879 } else
2880 PROC_UNLOCK(p);
2881 exit1(td, W_EXITCODE(0, sig));
2882 /* NOTREACHED */
2883}
2884
2885/*
2886 * Send queued SIGCHLD to parent when child process's state
2887 * is changed.
2888 */
2889static void
2890sigparent(struct proc *p, int reason, int status)
2891{
2892 PROC_LOCK_ASSERT(p, MA_OWNED);
2893 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2894
2895 if (p->p_ksi != NULL) {
2896 p->p_ksi->ksi_signo = SIGCHLD;
2897 p->p_ksi->ksi_code = reason;
2898 p->p_ksi->ksi_status = status;
2899 p->p_ksi->ksi_pid = p->p_pid;
2900 p->p_ksi->ksi_uid = p->p_ucred->cr_ruid;
2901 if (KSI_ONQ(p->p_ksi))
2902 return;
2903 }
2904 pksignal(p->p_pptr, SIGCHLD, p->p_ksi);
2905}
2906
2907static void
2908childproc_jobstate(struct proc *p, int reason, int status)
2909{
2910 struct sigacts *ps;
2911
2912 PROC_LOCK_ASSERT(p, MA_OWNED);
2913 PROC_LOCK_ASSERT(p->p_pptr, MA_OWNED);
2914
2915 /*
2916 * Wake up parent sleeping in kern_wait(), also send
2917 * SIGCHLD to parent, but SIGCHLD does not guarantee
2918 * that parent will awake, because parent may masked
2919 * the signal.
2920 */
2921 p->p_pptr->p_flag |= P_STATCHILD;
2922 wakeup(p->p_pptr);
2923
2924 ps = p->p_pptr->p_sigacts;
2925 mtx_lock(&ps->ps_mtx);
2926 if ((ps->ps_flag & PS_NOCLDSTOP) == 0) {
2927 mtx_unlock(&ps->ps_mtx);
2928 sigparent(p, reason, status);
2929 } else
2930 mtx_unlock(&ps->ps_mtx);
2931}
2932
2933void
2934childproc_stopped(struct proc *p, int reason)
2935{
2936 childproc_jobstate(p, reason, p->p_xstat);
2937}
2938
2939void
2940childproc_continued(struct proc *p)
2941{
2942 childproc_jobstate(p, CLD_CONTINUED, SIGCONT);
2943}
2944
2945void
2946childproc_exited(struct proc *p)
2947{
2948 int reason;
2949 int status = p->p_xstat; /* convert to int */
2950
2951 reason = CLD_EXITED;
2952 if (WCOREDUMP(status))
2953 reason = CLD_DUMPED;
2954 else if (WIFSIGNALED(status))
2955 reason = CLD_KILLED;
2956 /*
2957 * XXX avoid calling wakeup(p->p_pptr), the work is
2958 * done in exit1().
2959 */
2960 sigparent(p, reason, status);
2961}
2962
2963/*
2964 * We only have 1 character for the core count in the format
2965 * string, so the range will be 0-9
2966 */
2967#define MAX_NUM_CORES 10
2968static int num_cores = 5;
2969
2970static int
2971sysctl_debug_num_cores_check (SYSCTL_HANDLER_ARGS)
2972{
2973 int error;
2974 int new_val;
2975
2976 new_val = num_cores;
2977 error = sysctl_handle_int(oidp, &new_val, 0, req);
2978 if (error != 0 || req->newptr == NULL)
2979 return (error);
2980 if (new_val > MAX_NUM_CORES)
2981 new_val = MAX_NUM_CORES;
2982 if (new_val < 0)
2983 new_val = 0;
2984 num_cores = new_val;
2985 return (0);
2986}
2987SYSCTL_PROC(_debug, OID_AUTO, ncores, CTLTYPE_INT|CTLFLAG_RW,
2988 0, sizeof(int), sysctl_debug_num_cores_check, "I", "");
2989
2990#if defined(COMPRESS_USER_CORES)
2991int compress_user_cores = 1;
2992SYSCTL_INT(_kern, OID_AUTO, compress_user_cores, CTLFLAG_RW,
2993 &compress_user_cores, 0, "");
2994
2995int compress_user_cores_gzlevel = -1; /* default level */
2996SYSCTL_INT(_kern, OID_AUTO, compress_user_cores_gzlevel, CTLFLAG_RW,
2997 &compress_user_cores_gzlevel, -1, "user core gz compression level");
2998
2999#define GZ_SUFFIX ".gz"
3000#define GZ_SUFFIX_LEN 3
3001#endif
3002
3003static char corefilename[MAXPATHLEN] = {"%N.core"};
3004SYSCTL_STRING(_kern, OID_AUTO, corefile, CTLFLAG_RW, corefilename,
3005 sizeof(corefilename), "process corefile name format string");
3006
3007/*
3008 * expand_name(name, uid, pid, td, compress)
3009 * Expand the name described in corefilename, using name, uid, and pid.
3010 * corefilename is a printf-like string, with three format specifiers:
3011 * %N name of process ("name")
3012 * %P process id (pid)
3013 * %U user id (uid)
3014 * For example, "%N.core" is the default; they can be disabled completely
3015 * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
3016 * This is controlled by the sysctl variable kern.corefile (see above).
3017 */
3018static char *
3019expand_name(const char *name, uid_t uid, pid_t pid, struct thread *td,
3020 int compress)
3021{
3022 struct sbuf sb;
3023 const char *format;
3024 char *temp;
3025 size_t i;
3026 int indexpos;
3027 char *hostname;
3028
3029 hostname = NULL;
3030 format = corefilename;
3031 temp = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
3032 if (temp == NULL)
3033 return (NULL);
3034 indexpos = -1;
3035 (void)sbuf_new(&sb, temp, MAXPATHLEN, SBUF_FIXEDLEN);
3036 for (i = 0; format[i]; i++) {
3037 switch (format[i]) {
3038 case '%': /* Format character */
3039 i++;
3040 switch (format[i]) {
3041 case '%':
3042 sbuf_putc(&sb, '%');
3043 break;
3044 case 'H': /* hostname */
3045 if (hostname == NULL) {
3046 hostname = malloc(MAXHOSTNAMELEN,
3047 M_TEMP, M_NOWAIT);
3048 if (hostname == NULL) {
3049 log(LOG_ERR,
3050 "pid %ld (%s), uid (%lu): "
3051 "unable to alloc memory "
3052 "for corefile hostname\n",
3053 (long)pid, name,
3054 (u_long)uid);
3055 goto nomem;
3056 }
3057 }
3058 getcredhostname(td->td_ucred, hostname,
3059 MAXHOSTNAMELEN);
3060 sbuf_printf(&sb, "%s", hostname);
3061 break;
3062 case 'I': /* autoincrementing index */
3063 sbuf_printf(&sb, "0");
3064 indexpos = sbuf_len(&sb) - 1;
3065 break;
3066 case 'N': /* process name */
3067 sbuf_printf(&sb, "%s", name);
3068 break;
3069 case 'P': /* process id */
3070 sbuf_printf(&sb, "%u", pid);
3071 break;
3072 case 'U': /* user id */
3073 sbuf_printf(&sb, "%u", uid);
3074 break;
3075 default:
3076 log(LOG_ERR,
3077 "Unknown format character %c in "
3078 "corename `%s'\n", format[i], format);
3079 }
3080 break;
3081 default:
3082 sbuf_putc(&sb, format[i]);
3083 }
3084 }
3085 free(hostname, M_TEMP);
3086#ifdef COMPRESS_USER_CORES
3087 if (compress) {
3088 sbuf_printf(&sb, GZ_SUFFIX);
3089 }
3090#endif
3091 if (sbuf_overflowed(&sb)) {
3092 log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too "
3093 "long\n", (long)pid, name, (u_long)uid);
3094nomem:
3095 sbuf_delete(&sb);
3096 free(temp, M_TEMP);
3097 return (NULL);
3098 }
3099 sbuf_finish(&sb);
3100 sbuf_delete(&sb);
3101
3102 /*
3103 * If the core format has a %I in it, then we need to check
3104 * for existing corefiles before returning a name.
3105 * To do this we iterate over 0..num_cores to find a
3106 * non-existing core file name to use.
3107 */
3108 if (indexpos != -1) {
3109 struct nameidata nd;
3110 int error, n;
3111 int flags = O_CREAT | O_EXCL | FWRITE | O_NOFOLLOW;
3112 int cmode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
3113 int vfslocked;
3114
3115 for (n = 0; n < num_cores; n++) {
3116 temp[indexpos] = '0' + n;
3117 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE,
3118 temp, td);
3119 error = vn_open(&nd, &flags, cmode, NULL);
3120 if (error) {
3121 if (error == EEXIST) {
3122 continue;
3123 }
3124 log(LOG_ERR,
3125 "pid %d (%s), uid (%u): Path `%s' failed "
3126 "on initial open test, error = %d\n",
3127 pid, name, uid, temp, error);
3128 free(temp, M_TEMP);
3129 return (NULL);
3130 }
3131 vfslocked = NDHASGIANT(&nd);
3132 NDFREE(&nd, NDF_ONLY_PNBUF);
3133 VOP_UNLOCK(nd.ni_vp, 0);
3134 error = vn_close(nd.ni_vp, FWRITE, td->td_ucred, td);
3135 VFS_UNLOCK_GIANT(vfslocked);
3136 if (error) {
3137 log(LOG_ERR,
3138 "pid %d (%s), uid (%u): Path `%s' failed "
3139 "on close after initial open test, "
3140 "error = %d\n",
3141 pid, name, uid, temp, error);
3142 free(temp, M_TEMP);
3143 return (NULL);
3144 }
3145 break;
3146 }
3147 }
3148 return (temp);
3149}
3150
3151/*
3152 * Dump a process' core. The main routine does some
3153 * policy checking, and creates the name of the coredump;
3154 * then it passes on a vnode and a size limit to the process-specific
3155 * coredump routine if there is one; if there _is not_ one, it returns
3156 * ENOSYS; otherwise it returns the error from the process-specific routine.
3157 */
3158
3159static int
3160coredump(struct thread *td)
3161{
3162 struct proc *p = td->td_proc;
3163 register struct vnode *vp;
3164 register struct ucred *cred = td->td_ucred;
3165 struct flock lf;
3166 struct nameidata nd;
3167 struct vattr vattr;
3168 int error, error1, flags, locked;
3169 struct mount *mp;
3170 char *name; /* name of corefile */
3171 off_t limit;
3172 int vfslocked;
3173 int compress;
3174
3175#ifdef COMPRESS_USER_CORES
3176 compress = compress_user_cores;
3177#else
3178 compress = 0;
3179#endif
3180 PROC_LOCK_ASSERT(p, MA_OWNED);
3181 MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
3182 _STOPEVENT(p, S_CORE, 0);
3183
3184 name = expand_name(p->p_comm, td->td_ucred->cr_uid, p->p_pid, td,
3185 compress);
3186 if (name == NULL) {
3187 PROC_UNLOCK(p);
3188#ifdef AUDIT
3189 audit_proc_coredump(td, NULL, EINVAL);
3190#endif
3191 return (EINVAL);
3192 }
3193 if (((sugid_coredump == 0) && p->p_flag & P_SUGID) || do_coredump == 0) {
3194 PROC_UNLOCK(p);
3195#ifdef AUDIT
3196 audit_proc_coredump(td, name, EFAULT);
3197#endif
3198 free(name, M_TEMP);
3199 return (EFAULT);
3200 }
3201
3202 /*
3203 * Note that the bulk of limit checking is done after
3204 * the corefile is created. The exception is if the limit
3205 * for corefiles is 0, in which case we don't bother
3206 * creating the corefile at all. This layout means that
3207 * a corefile is truncated instead of not being created,
3208 * if it is larger than the limit.
3209 */
3210 limit = (off_t)lim_cur(p, RLIMIT_CORE);
3211 PROC_UNLOCK(p);
3212 if (limit == 0) {
3213#ifdef AUDIT
3214 audit_proc_coredump(td, name, EFBIG);
3215#endif
3216 free(name, M_TEMP);
3217 return (EFBIG);
3218 }
3219
3220restart:
3221 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, name, td);
3222 flags = O_CREAT | FWRITE | O_NOFOLLOW;
3223 error = vn_open_cred(&nd, &flags, S_IRUSR | S_IWUSR, VN_OPEN_NOAUDIT,
3224 cred, NULL);
3225 if (error) {
3226#ifdef AUDIT
3227 audit_proc_coredump(td, name, error);
3228#endif
3229 free(name, M_TEMP);
3230 return (error);
3231 }
3232 vfslocked = NDHASGIANT(&nd);
3233 NDFREE(&nd, NDF_ONLY_PNBUF);
3234 vp = nd.ni_vp;
3235
3236 /* Don't dump to non-regular files or files with links. */
3237 if (vp->v_type != VREG ||
3238 VOP_GETATTR(vp, &vattr, cred) || vattr.va_nlink != 1) {
3239 VOP_UNLOCK(vp, 0);
3240 error = EFAULT;
3241 goto close;
3242 }
3243
3244 VOP_UNLOCK(vp, 0);
3245 lf.l_whence = SEEK_SET;
3246 lf.l_start = 0;
3247 lf.l_len = 0;
3248 lf.l_type = F_WRLCK;
3249 locked = (VOP_ADVLOCK(vp, (caddr_t)p, F_SETLK, &lf, F_FLOCK) == 0);
3250
3251 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) {
3252 lf.l_type = F_UNLCK;
3253 if (locked)
3254 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3255 if ((error = vn_close(vp, FWRITE, cred, td)) != 0)
3256 goto out;
3257 if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
3258 goto out;
3259 VFS_UNLOCK_GIANT(vfslocked);
3260 goto restart;
3261 }
3262
3263 VATTR_NULL(&vattr);
3264 vattr.va_size = 0;
3265 if (set_core_nodump_flag)
3266 vattr.va_flags = UF_NODUMP;
3267 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3268 VOP_SETATTR(vp, &vattr, cred);
3269 VOP_UNLOCK(vp, 0);
3270 vn_finished_write(mp);
3271 PROC_LOCK(p);
3272 p->p_acflag |= ACORE;
3273 PROC_UNLOCK(p);
3274
3275 error = p->p_sysent->sv_coredump ?
3276 p->p_sysent->sv_coredump(td, vp, limit, compress ? IMGACT_CORE_COMPRESS : 0) :
3277 ENOSYS;
3278
3279 if (locked) {
3280 lf.l_type = F_UNLCK;
3281 VOP_ADVLOCK(vp, (caddr_t)p, F_UNLCK, &lf, F_FLOCK);
3282 }
3283close:
3284 error1 = vn_close(vp, FWRITE, cred, td);
3285 if (error == 0)
3286 error = error1;
3287out:
3288#ifdef AUDIT
3289 audit_proc_coredump(td, name, error);
3290#endif
3291 free(name, M_TEMP);
3292 VFS_UNLOCK_GIANT(vfslocked);
3293 return (error);
3294}
3295
3296/*
3297 * Nonexistent system call-- signal process (may want to handle it). Flag
3298 * error in case process won't see signal immediately (blocked or ignored).
3299 */
3300#ifndef _SYS_SYSPROTO_H_
3301struct nosys_args {
3302 int dummy;
3303};
3304#endif
3305/* ARGSUSED */
3306int
3307nosys(td, args)
3308 struct thread *td;
3309 struct nosys_args *args;
3310{
3311 struct proc *p = td->td_proc;
3312
3313 PROC_LOCK(p);
3314 psignal(p, SIGSYS);
3315 PROC_UNLOCK(p);
3316 return (ENOSYS);
3317}
3318
3319/*
3320 * Send a SIGIO or SIGURG signal to a process or process group using stored
3321 * credentials rather than those of the current process.
3322 */
3323void
3324pgsigio(sigiop, sig, checkctty)
3325 struct sigio **sigiop;
3326 int sig, checkctty;
3327{
3328 ksiginfo_t ksi;
3329 struct sigio *sigio;
3330
3331 ksiginfo_init(&ksi);
3332 ksi.ksi_signo = sig;
3333 ksi.ksi_code = SI_KERNEL;
3334
3335 SIGIO_LOCK();
3336 sigio = *sigiop;
3337 if (sigio == NULL) {
3338 SIGIO_UNLOCK();
3339 return;
3340 }
3341 if (sigio->sio_pgid > 0) {
3342 PROC_LOCK(sigio->sio_proc);
3343 if (CANSIGIO(sigio->sio_ucred, sigio->sio_proc->p_ucred))
3344 psignal(sigio->sio_proc, sig);
3345 PROC_UNLOCK(sigio->sio_proc);
3346 } else if (sigio->sio_pgid < 0) {
3347 struct proc *p;
3348
3349 PGRP_LOCK(sigio->sio_pgrp);
3350 LIST_FOREACH(p, &sigio->sio_pgrp->pg_members, p_pglist) {
3351 PROC_LOCK(p);
3352 if (CANSIGIO(sigio->sio_ucred, p->p_ucred) &&
3353 (checkctty == 0 || (p->p_flag & P_CONTROLT)))
3354 psignal(p, sig);
3355 PROC_UNLOCK(p);
3356 }
3357 PGRP_UNLOCK(sigio->sio_pgrp);
3358 }
3359 SIGIO_UNLOCK();
3360}
3361
3362static int
3363filt_sigattach(struct knote *kn)
3364{
3365 struct proc *p = curproc;
3366
3367 kn->kn_ptr.p_proc = p;
3368 kn->kn_flags |= EV_CLEAR; /* automatically set */
3369
3370 knlist_add(&p->p_klist, kn, 0);
3371
3372 return (0);
3373}
3374
3375static void
3376filt_sigdetach(struct knote *kn)
3377{
3378 struct proc *p = kn->kn_ptr.p_proc;
3379
3380 knlist_remove(&p->p_klist, kn, 0);
3381}
3382
3383/*
3384 * signal knotes are shared with proc knotes, so we apply a mask to
3385 * the hint in order to differentiate them from process hints. This
3386 * could be avoided by using a signal-specific knote list, but probably
3387 * isn't worth the trouble.
3388 */
3389static int
3390filt_signal(struct knote *kn, long hint)
3391{
3392
3393 if (hint & NOTE_SIGNAL) {
3394 hint &= ~NOTE_SIGNAL;
3395
3396 if (kn->kn_id == hint)
3397 kn->kn_data++;
3398 }
3399 return (kn->kn_data != 0);
3400}
3401
3402struct sigacts *
3403sigacts_alloc(void)
3404{
3405 struct sigacts *ps;
3406
3407 ps = malloc(sizeof(struct sigacts), M_SUBPROC, M_WAITOK | M_ZERO);
3408 ps->ps_refcnt = 1;
3409 mtx_init(&ps->ps_mtx, "sigacts", NULL, MTX_DEF);
3410 return (ps);
3411}
3412
3413void
3414sigacts_free(struct sigacts *ps)
3415{
3416
3417 mtx_lock(&ps->ps_mtx);
3418 ps->ps_refcnt--;
3419 if (ps->ps_refcnt == 0) {
3420 mtx_destroy(&ps->ps_mtx);
3421 free(ps, M_SUBPROC);
3422 } else
3423 mtx_unlock(&ps->ps_mtx);
3424}
3425
3426struct sigacts *
3427sigacts_hold(struct sigacts *ps)
3428{
3429 mtx_lock(&ps->ps_mtx);
3430 ps->ps_refcnt++;
3431 mtx_unlock(&ps->ps_mtx);
3432 return (ps);
3433}
3434
3435void
3436sigacts_copy(struct sigacts *dest, struct sigacts *src)
3437{
3438
3439 KASSERT(dest->ps_refcnt == 1, ("sigacts_copy to shared dest"));
3440 mtx_lock(&src->ps_mtx);
3441 bcopy(src, dest, offsetof(struct sigacts, ps_refcnt));
3442 mtx_unlock(&src->ps_mtx);
3443}
3444
3445int
3446sigacts_shared(struct sigacts *ps)
3447{
3448 int shared;
3449
3450 mtx_lock(&ps->ps_mtx);
3451 shared = ps->ps_refcnt > 1;
3452 mtx_unlock(&ps->ps_mtx);
3453 return (shared);
3454}
|