2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1989, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
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13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
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18 * notice, this list of conditions and the following disclaimer in the
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20 * 3. Neither the name of the University nor the names of its contributors
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37 #include <sys/cdefs.h>
39 #include "opt_ktrace.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/sysproto.h>
44 #include <sys/capsicum.h>
45 #include <sys/eventhandler.h>
46 #include <sys/kernel.h>
48 #include <sys/malloc.h>
50 #include <sys/mutex.h>
52 #include <sys/procdesc.h>
56 #include <sys/vmmeter.h>
57 #include <sys/vnode.h>
58 #include <sys/racct.h>
59 #include <sys/resourcevar.h>
61 #include <sys/signalvar.h>
62 #include <sys/sched.h>
64 #include <sys/syscallsubr.h>
65 #include <sys/sysctl.h>
66 #include <sys/syslog.h>
67 #include <sys/ptrace.h>
68 #include <sys/acct.h> /* for acct_process() function prototype */
69 #include <sys/filedesc.h>
73 #include <sys/sysent.h>
74 #include <sys/timers.h>
75 #include <sys/umtxvar.h>
77 #include <sys/ktrace.h>
80 #include <security/audit/audit.h>
81 #include <security/mac/mac_framework.h>
84 #include <vm/vm_extern.h>
85 #include <vm/vm_param.h>
87 #include <vm/vm_map.h>
88 #include <vm/vm_page.h>
92 #include <sys/dtrace_bsd.h>
93 dtrace_execexit_func_t dtrace_fasttrap_exit;
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE1(proc, , , exit, "int");
99 static int kern_kill_on_dbg_exit = 1;
100 SYSCTL_INT(_kern, OID_AUTO, kill_on_debugger_exit, CTLFLAG_RWTUN,
101 &kern_kill_on_dbg_exit, 0,
102 "Kill ptraced processes when debugger exits");
104 static bool kern_wait_dequeue_sigchld = 1;
105 SYSCTL_BOOL(_kern, OID_AUTO, wait_dequeue_sigchld, CTLFLAG_RWTUN,
106 &kern_wait_dequeue_sigchld, 0,
107 "Dequeue SIGCHLD on wait(2) for live process");
110 proc_realparent(struct proc *child)
112 struct proc *p, *parent;
114 sx_assert(&proctree_lock, SX_LOCKED);
115 if ((child->p_treeflag & P_TREE_ORPHANED) == 0)
116 return (child->p_pptr->p_pid == child->p_oppid ?
117 child->p_pptr : child->p_reaper);
118 for (p = child; (p->p_treeflag & P_TREE_FIRST_ORPHAN) == 0;) {
119 /* Cannot use LIST_PREV(), since the list head is not known. */
120 p = __containerof(p->p_orphan.le_prev, struct proc,
122 KASSERT((p->p_treeflag & P_TREE_ORPHANED) != 0,
123 ("missing P_ORPHAN %p", p));
125 parent = __containerof(p->p_orphan.le_prev, struct proc,
131 reaper_abandon_children(struct proc *p, bool exiting)
133 struct proc *p1, *p2, *ptmp;
135 sx_assert(&proctree_lock, SX_XLOCKED);
136 KASSERT(p != initproc, ("reaper_abandon_children for initproc"));
137 if ((p->p_treeflag & P_TREE_REAPER) == 0)
140 LIST_FOREACH_SAFE(p2, &p->p_reaplist, p_reapsibling, ptmp) {
141 LIST_REMOVE(p2, p_reapsibling);
143 p2->p_reapsubtree = p->p_reapsubtree;
144 LIST_INSERT_HEAD(&p1->p_reaplist, p2, p_reapsibling);
145 if (exiting && p2->p_pptr == p) {
147 proc_reparent(p2, p1, true);
151 KASSERT(LIST_EMPTY(&p->p_reaplist), ("p_reaplist not empty"));
152 p->p_treeflag &= ~P_TREE_REAPER;
156 reaper_clear(struct proc *p)
161 sx_assert(&proctree_lock, SX_LOCKED);
162 LIST_REMOVE(p, p_reapsibling);
163 if (p->p_reapsubtree == 1)
166 LIST_FOREACH(p1, &p->p_reaper->p_reaplist, p_reapsibling) {
167 if (p1->p_reapsubtree == p->p_reapsubtree) {
173 proc_id_clear(PROC_ID_REAP, p->p_reapsubtree);
177 proc_clear_orphan(struct proc *p)
181 sx_assert(&proctree_lock, SA_XLOCKED);
182 if ((p->p_treeflag & P_TREE_ORPHANED) == 0)
184 if ((p->p_treeflag & P_TREE_FIRST_ORPHAN) != 0) {
185 p1 = LIST_NEXT(p, p_orphan);
187 p1->p_treeflag |= P_TREE_FIRST_ORPHAN;
188 p->p_treeflag &= ~P_TREE_FIRST_ORPHAN;
190 LIST_REMOVE(p, p_orphan);
191 p->p_treeflag &= ~P_TREE_ORPHANED;
195 exit_onexit(struct proc *p)
197 MPASS(p->p_numthreads == 1);
198 umtx_thread_exit(FIRST_THREAD_IN_PROC(p));
202 * exit -- death of process.
205 sys_exit(struct thread *td, struct exit_args *uap)
208 exit1(td, uap->rval, 0);
213 proc_set_p2_wexit(struct proc *p)
215 PROC_LOCK_ASSERT(p, MA_OWNED);
216 p->p_flag2 |= P2_WEXIT;
220 * Exit: deallocate address space and other resources, change proc state to
221 * zombie, and unlink proc from allproc and parent's lists. Save exit status
222 * and rusage for wait(). Check for child processes and orphan them.
225 exit1(struct thread *td, int rval, int signo)
227 struct proc *p, *nq, *q, *t;
229 ksiginfo_t *ksi, *ksi1;
232 mtx_assert(&Giant, MA_NOTOWNED);
233 KASSERT(rval == 0 || signo == 0, ("exit1 rv %d sig %d", rval, signo));
234 TSPROCEXIT(td->td_proc->p_pid);
238 * In case we're rebooting we just let init die in order to
239 * work around an issues where pid 1 might get a fatal signal.
240 * For instance, if network interface serving NFS root is
241 * going down due to reboot, page-in requests for text are
244 if (p == initproc && rebooting == 0) {
245 printf("init died (signal %d, exit %d)\n", signo, rval);
246 panic("Going nowhere without my init!");
250 * Process deferred operations, designated with ASTF_KCLEAR.
251 * For instance, we need to deref SU mp, since the thread does
252 * not return to userspace, and wait for geom to stabilize.
257 * MUST abort all other threads before proceeding past here.
260 proc_set_p2_wexit(p);
263 * First check if some other thread or external request got
264 * here before us. If so, act appropriately: exit or suspend.
265 * We must ensure that stop requests are handled before we set
268 thread_suspend_check(0);
269 while (p->p_flag & P_HADTHREADS) {
271 * Kill off the other threads. This requires
272 * some co-operation from other parts of the kernel
273 * so it may not be instantaneous. With this state set
274 * any thread attempting to interruptibly
275 * sleep will return immediately with EINTR or EWOULDBLOCK
276 * which will hopefully force them to back out to userland
277 * freeing resources as they go. Any thread attempting
278 * to return to userland will thread_exit() from ast().
279 * thread_exit() will unsuspend us when the last of the
280 * other threads exits.
281 * If there is already a thread singler after resumption,
282 * calling thread_single() will fail; in that case, we just
283 * re-check all suspension request, the thread should
284 * either be suspended there or exit.
286 if (!thread_single(p, SINGLE_EXIT))
288 * All other activity in this process is now
289 * stopped. Threading support has been turned
294 * Recheck for new stop or suspend requests which
295 * might appear while process lock was dropped in
298 thread_suspend_check(0);
300 KASSERT(p->p_numthreads == 1,
301 ("exit1: proc %p exiting with %d threads", p, p->p_numthreads));
302 racct_sub(p, RACCT_NTHR, 1);
304 /* Let event handler change exit status */
309 * Ignore any pending request to stop due to a stop signal.
310 * Once P_WEXIT is set, future requests will be ignored as
313 p->p_flag &= ~P_STOPPED_SIG;
314 KASSERT(!P_SHOULDSTOP(p), ("exiting process is stopped"));
316 /* Note that we are exiting. */
317 p->p_flag |= P_WEXIT;
320 * Wait for any processes that have a hold on our vmspace to
321 * release their reference.
323 while (p->p_lock > 0)
324 msleep(&p->p_lock, &p->p_mtx, PWAIT, "exithold", 0);
327 /* Drain the limit callout while we don't have the proc locked */
328 callout_drain(&p->p_limco);
332 * The Sun BSM exit token contains two components: an exit status as
333 * passed to exit(), and a return value to indicate what sort of exit
334 * it was. The exit status is WEXITSTATUS(rv), but it's not clear
335 * what the return value is.
337 AUDIT_ARG_EXIT(rval, 0);
338 AUDIT_SYSCALL_EXIT(0, td);
341 /* Are we a task leader with peers? */
342 if (p->p_peers != NULL && p == p->p_leader) {
343 mtx_lock(&ppeers_lock);
347 kern_psignal(q, SIGKILL);
351 while (p->p_peers != NULL)
352 msleep(p, &ppeers_lock, PWAIT, "exit1", 0);
353 mtx_unlock(&ppeers_lock);
359 * Check if any loadable modules need anything done at process exit.
360 * E.g. SYSV IPC stuff.
361 * Event handler could change exit status.
362 * XXX what if one of these generates an error?
364 EVENTHANDLER_DIRECT_INVOKE(process_exit, p);
367 * If parent is waiting for us to exit or exec,
368 * P_PPWAIT is set; we will wakeup the parent below.
375 * Stop the real interval timer. If the handler is currently
376 * executing, prevent it from rearming itself and let it finish.
378 if (timevalisset(&p->p_realtimer.it_value) &&
379 callout_stop(&p->p_itcallout) == 0) {
380 timevalclear(&p->p_realtimer.it_interval);
382 callout_drain(&p->p_itcallout);
387 if (p->p_sysent->sv_onexit != NULL)
388 p->p_sysent->sv_onexit(p);
392 * Reset any sigio structures pointing to us as a result of
393 * F_SETOWN with our pid. The P_WEXIT flag interlocks with fsetown().
395 funsetownlst(&p->p_sigiolst);
398 * Close open files and release open-file table.
405 * Remove ourself from our leader's peer list and wake our leader.
407 if (p->p_leader->p_peers != NULL) {
408 mtx_lock(&ppeers_lock);
409 if (p->p_leader->p_peers != NULL) {
411 while (q->p_peers != p)
413 q->p_peers = p->p_peers;
416 mtx_unlock(&ppeers_lock);
419 exec_free_abi_mappings(p);
421 (void)acct_process(td);
427 * Release reference to text vnode etc
429 if (p->p_textvp != NULL) {
433 if (p->p_textdvp != NULL) {
437 if (p->p_binname != NULL) {
438 free(p->p_binname, M_PARGS);
443 * Release our limits structure.
445 lim_free(p->p_limit);
451 * Call machine-dependent code to release any
452 * machine-dependent resources other than the address space.
453 * The address space is released by "vmspace_exitfree(p)" in
458 WITNESS_WARN(WARN_PANIC, NULL, "process (pid %d) exiting", p->p_pid);
461 * Remove from allproc. It still sits in the hash.
463 sx_xlock(&allproc_lock);
464 LIST_REMOVE(p, p_list);
468 * Used by ddb's 'ps' command to find this process via the
471 p->p_list.le_prev = NULL;
473 prison_proc_unlink(p->p_ucred->cr_prison, p);
474 sx_xunlock(&allproc_lock);
476 sx_xlock(&proctree_lock);
477 if ((p->p_flag & (P_TRACED | P_PPWAIT | P_PPTRACE)) != 0) {
479 p->p_flag &= ~(P_TRACED | P_PPWAIT | P_PPTRACE);
484 * killjobc() might drop and re-acquire proctree_lock to
485 * revoke control tty if exiting process was a session leader.
490 * Reparent all children processes:
491 * - traced ones to the original parent (or init if we are that parent)
494 q = LIST_FIRST(&p->p_children);
495 if (q != NULL) /* only need this if any child is S_ZOMB */
497 for (; q != NULL; q = nq) {
498 nq = LIST_NEXT(q, p_sibling);
499 ksi = ksiginfo_alloc(M_WAITOK);
501 q->p_sigparent = SIGCHLD;
503 if ((q->p_flag & P_TRACED) == 0) {
504 proc_reparent(q, q->p_reaper, true);
505 if (q->p_state == PRS_ZOMBIE) {
507 * Inform reaper about the reparented
508 * zombie, since wait(2) has something
509 * new to report. Guarantee queueing
510 * of the SIGCHLD signal, similar to
511 * the _exit() behaviour, by providing
512 * our ksiginfo. Ksi is freed by the
515 if (q->p_ksi == NULL) {
518 ksiginfo_copy(q->p_ksi, ksi);
519 ksi->ksi_flags |= KSI_INS;
523 PROC_LOCK(q->p_reaper);
524 pksignal(q->p_reaper, SIGCHLD, ksi1);
525 PROC_UNLOCK(q->p_reaper);
526 } else if (q->p_pdeathsig > 0) {
528 * The child asked to received a signal
531 kern_psignal(q, q->p_pdeathsig);
535 * Traced processes are killed by default
536 * since their existence means someone is
539 t = proc_realparent(q);
541 proc_reparent(q, q->p_reaper, true);
544 proc_reparent(q, t, true);
548 * Since q was found on our children list, the
549 * proc_reparent() call moved q to the orphan
550 * list due to present P_TRACED flag. Clear
551 * orphan link for q now while q is locked.
553 proc_clear_orphan(q);
554 q->p_flag &= ~P_TRACED;
555 q->p_flag2 &= ~P2_PTRACE_FSTP;
558 FOREACH_THREAD_IN_PROC(q, tdt) {
559 tdt->td_dbgflags &= ~(TDB_SUSPEND | TDB_XSIG |
563 if (kern_kill_on_dbg_exit) {
564 q->p_flag &= ~P_STOPPED_TRACE;
565 kern_psignal(q, SIGKILL);
566 } else if ((q->p_flag & (P_STOPPED_TRACE |
567 P_STOPPED_SIG)) != 0) {
568 sigqueue_delete_proc(q, SIGTRAP);
578 * Also get rid of our orphans.
580 while ((q = LIST_FIRST(&p->p_orphans)) != NULL) {
582 KASSERT(q->p_oppid == p->p_pid,
583 ("orphan %p of %p has unexpected oppid %d", q, p,
585 q->p_oppid = q->p_reaper->p_pid;
588 * If we are the real parent of this process
589 * but it has been reparented to a debugger, then
590 * check if it asked for a signal when we exit.
592 if (q->p_pdeathsig > 0)
593 kern_psignal(q, q->p_pdeathsig);
594 CTR2(KTR_PTRACE, "exit: pid %d, clearing orphan %d", p->p_pid,
596 proc_clear_orphan(q);
601 if (SDT_PROBES_ENABLED()) {
602 int reason = CLD_EXITED;
603 if (WCOREDUMP(signo))
605 else if (WIFSIGNALED(signo))
607 SDT_PROBE1(proc, , , exit, reason);
611 /* Save exit status. */
615 if (p->p_sysent->sv_ontdexit != NULL)
616 p->p_sysent->sv_ontdexit(td);
620 * Tell the DTrace fasttrap provider about the exit if it
621 * has declared an interest.
623 if (dtrace_fasttrap_exit)
624 dtrace_fasttrap_exit(p);
628 * Notify interested parties of our demise.
630 KNOTE_LOCKED(p->p_klist, NOTE_EXIT);
633 * If this is a process with a descriptor, we may not need to deliver
634 * a signal to the parent. proctree_lock is held over
635 * procdesc_exit() to serialize concurrent calls to close() and
639 if (p->p_procdesc == NULL || procdesc_exit(p)) {
641 * Notify parent that we're gone. If parent has the
642 * PS_NOCLDWAIT flag set, or if the handler is set to SIG_IGN,
643 * notify process 1 instead (and hope it will handle this
646 PROC_LOCK(p->p_pptr);
647 mtx_lock(&p->p_pptr->p_sigacts->ps_mtx);
648 if (p->p_pptr->p_sigacts->ps_flag &
649 (PS_NOCLDWAIT | PS_CLDSIGIGN)) {
652 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
655 proc_reparent(p, p->p_reaper, true);
656 p->p_sigparent = SIGCHLD;
657 PROC_LOCK(p->p_pptr);
660 * Notify parent, so in case he was wait(2)ing or
661 * executing waitpid(2) with our pid, he will
666 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
668 if (p->p_pptr == p->p_reaper || p->p_pptr == initproc) {
670 } else if (p->p_sigparent != 0) {
671 if (p->p_sigparent == SIGCHLD) {
673 } else { /* LINUX thread */
678 PROC_LOCK(p->p_pptr);
679 sx_xunlock(&proctree_lock);
681 if (signal_parent == 1) {
683 } else if (signal_parent == 2) {
684 kern_psignal(p->p_pptr, p->p_sigparent);
687 /* Tell the prison that we are gone. */
688 prison_proc_free(p->p_ucred->cr_prison);
691 * The state PRS_ZOMBIE prevents other processes from sending
692 * signal to the process, to avoid memory leak, we free memory
693 * for signal queue at the time when the state is set.
695 sigqueue_flush(&p->p_sigqueue);
696 sigqueue_flush(&td->td_sigqueue);
699 * We have to wait until after acquiring all locks before
700 * changing p_state. We need to avoid all possible context
701 * switches (including ones from blocking on a mutex) while
702 * marked as a zombie. We also have to set the zombie state
703 * before we release the parent process' proc lock to avoid
704 * a lost wakeup. So, we first call wakeup, then we grab the
705 * sched lock, update the state, and release the parent process'
709 cv_broadcast(&p->p_pwait);
710 sched_exit(p->p_pptr, td);
712 p->p_state = PRS_ZOMBIE;
713 PROC_UNLOCK(p->p_pptr);
716 * Save our children's rusage information in our exit rusage.
719 ruadd(&p->p_ru, &p->p_rux, &p->p_stats->p_cru, &p->p_crux);
723 * Make sure the scheduler takes this thread out of its tables etc.
724 * This will also release this thread's reference to the ucred.
725 * Other thread parts to release include pcb bits and such.
730 #ifndef _SYS_SYSPROTO_H_
739 sys_abort2(struct thread *td, struct abort2_args *uap)
746 if (nargs < 0 || nargs > nitems(uargs))
750 if (uap->args != NULL) {
751 error = copyin(uap->args, uargs,
752 nargs * sizeof(void *));
760 return (kern_abort2(td, uap->why, nargs, uargsp));
766 * why - user pointer to why
767 * nargs - number of arguments copied or -1 if an error occurred in copying
768 * args - pointer to an array of pointers in kernel format
771 kern_abort2(struct thread *td, const char *why, int nargs, void **uargs)
773 struct proc *p = td->td_proc;
778 * Do it right now so we can log either proper call of abort2(), or
779 * note, that invalid argument was passed. 512 is big enough to
780 * handle 16 arguments' descriptions with additional comments.
782 sb = sbuf_new(NULL, NULL, 512, SBUF_FIXEDLEN);
784 sbuf_printf(sb, "%s(pid %d uid %d) aborted: ",
785 p->p_comm, p->p_pid, td->td_ucred->cr_uid);
787 * Since we can't return from abort2(), send SIGKILL in cases, where
788 * abort2() was called improperly
791 /* Prevent from DoSes from user-space. */
794 KASSERT(nargs >= 0 && nargs <= 16, ("called with too many args (%d)",
797 * Limit size of 'reason' string to 128. Will fit even when
798 * maximal number of arguments was chosen to be logged.
801 error = sbuf_copyin(sb, why, 128);
805 sbuf_cat(sb, "(null)");
809 for (i = 0;i < nargs; i++)
810 sbuf_printf(sb, "%s%p", i == 0 ? "" : ", ", uargs[i]);
814 * Final stage: arguments were proper, string has been
815 * successfully copied from userspace, and copying pointers
816 * from user-space succeed.
820 if (sig == SIGKILL) {
822 sbuf_cat(sb, " (Reason text inaccessible)");
826 log(LOG_INFO, "%s", sbuf_data(sb));
835 * The dirty work is handled by kern_wait().
838 owait(struct thread *td, struct owait_args *uap __unused)
842 error = kern_wait(td, WAIT_ANY, &status, 0, NULL);
844 td->td_retval[1] = status;
847 #endif /* COMPAT_43 */
850 * The dirty work is handled by kern_wait().
853 sys_wait4(struct thread *td, struct wait4_args *uap)
855 struct rusage ru, *rup;
858 if (uap->rusage != NULL)
862 error = kern_wait(td, uap->pid, &status, uap->options, rup);
863 if (uap->status != NULL && error == 0 && td->td_retval[0] != 0)
864 error = copyout(&status, uap->status, sizeof(status));
865 if (uap->rusage != NULL && error == 0 && td->td_retval[0] != 0)
866 error = copyout(&ru, uap->rusage, sizeof(struct rusage));
871 sys_wait6(struct thread *td, struct wait6_args *uap)
873 struct __wrusage wru, *wrup;
879 idtype = uap->idtype;
882 if (uap->wrusage != NULL)
887 if (uap->info != NULL) {
889 bzero(sip, sizeof(*sip));
894 * We expect all callers of wait6() to know about WEXITED and
897 error = kern_wait6(td, idtype, id, &status, uap->options, wrup, sip);
899 if (uap->status != NULL && error == 0 && td->td_retval[0] != 0)
900 error = copyout(&status, uap->status, sizeof(status));
901 if (uap->wrusage != NULL && error == 0 && td->td_retval[0] != 0)
902 error = copyout(&wru, uap->wrusage, sizeof(wru));
903 if (uap->info != NULL && error == 0)
904 error = copyout(&si, uap->info, sizeof(si));
909 * Reap the remains of a zombie process and optionally return status and
910 * rusage. Asserts and will release both the proctree_lock and the process
911 * lock as part of its work.
914 proc_reap(struct thread *td, struct proc *p, int *status, int options)
918 sx_assert(&proctree_lock, SA_XLOCKED);
919 PROC_LOCK_ASSERT(p, MA_OWNED);
920 KASSERT(p->p_state == PRS_ZOMBIE, ("proc_reap: !PRS_ZOMBIE"));
922 mtx_spin_wait_unlocked(&p->p_slock);
927 *status = KW_EXITCODE(p->p_xexit, p->p_xsig);
928 if (options & WNOWAIT) {
930 * Only poll, returning the status. Caller does not wish to
931 * release the proc struct just yet.
934 sx_xunlock(&proctree_lock);
939 sigqueue_take(p->p_ksi);
943 * If we got the child via a ptrace 'attach', we need to give it back
946 if (p->p_oppid != p->p_pptr->p_pid) {
948 t = proc_realparent(p);
952 "wait: traced child %d moved back to parent %d", p->p_pid,
954 proc_reparent(p, t, false);
956 pksignal(t, SIGCHLD, p->p_ksi);
958 cv_broadcast(&p->p_pwait);
960 sx_xunlock(&proctree_lock);
966 * Remove other references to this process to ensure we have an
967 * exclusive reference.
969 sx_xlock(PIDHASHLOCK(p->p_pid));
970 LIST_REMOVE(p, p_hash);
971 sx_xunlock(PIDHASHLOCK(p->p_pid));
972 LIST_REMOVE(p, p_sibling);
973 reaper_abandon_children(p, true);
976 proc_clear_orphan(p);
979 if (p->p_procdesc != NULL)
981 sx_xunlock(&proctree_lock);
983 proc_id_clear(PROC_ID_PID, p->p_pid);
986 knlist_detach(p->p_klist);
991 * Removal from allproc list and process group list paired with
992 * PROC_LOCK which was executed during that time should guarantee
993 * nothing can reach this process anymore. As such further locking
996 p->p_xexit = p->p_xsig = 0; /* XXX: why? */
999 ruadd(&q->p_stats->p_cru, &q->p_crux, &p->p_ru, &p->p_rux);
1003 * Decrement the count of procs running with this uid.
1005 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0);
1008 * Destroy resource accounting information associated with the process.
1013 racct_sub(p, RACCT_NPROC, 1);
1020 * Free credentials, arguments, and sigacts.
1023 pargs_drop(p->p_args);
1025 sigacts_free(p->p_sigacts);
1026 p->p_sigacts = NULL;
1029 * Do any thread-system specific cleanups.
1034 * Give vm and machine-dependent layer a chance to free anything that
1035 * cpu_exit couldn't release while still running in process context.
1039 mac_proc_destroy(p);
1042 KASSERT(FIRST_THREAD_IN_PROC(p),
1043 ("proc_reap: no residual thread!"));
1044 uma_zfree(proc_zone, p);
1045 atomic_add_int(&nprocs, -1);
1049 proc_to_reap(struct thread *td, struct proc *p, idtype_t idtype, id_t id,
1050 int *status, int options, struct __wrusage *wrusage, siginfo_t *siginfo,
1055 sx_assert(&proctree_lock, SA_XLOCKED);
1061 if (p->p_procdesc == NULL ||
1062 (p->p_pptr == td->td_proc &&
1063 (p->p_flag & P_TRACED) != 0)) {
1070 if (p->p_pid != (pid_t)id) {
1076 if (p->p_pgid != (pid_t)id) {
1082 if (p->p_session->s_sid != (pid_t)id) {
1088 if (p->p_ucred->cr_uid != (uid_t)id) {
1094 if (p->p_ucred->cr_gid != (gid_t)id) {
1100 if (p->p_ucred->cr_prison->pr_id != (int)id) {
1106 * It seems that the thread structures get zeroed out
1107 * at process exit. This makes it impossible to
1108 * support P_SETID, P_CID or P_CPUID.
1115 if (p_canwait(td, p)) {
1120 if (((options & WEXITED) == 0) && (p->p_state == PRS_ZOMBIE)) {
1126 * This special case handles a kthread spawned by linux_clone
1127 * (see linux_misc.c). The linux_wait4 and linux_waitpid
1128 * functions need to be able to distinguish between waiting
1129 * on a process and waiting on a thread. It is a thread if
1130 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option
1131 * signifies we want to wait for threads and not processes.
1133 if ((p->p_sigparent != SIGCHLD) ^
1134 ((options & WLINUXCLONE) != 0)) {
1139 if (siginfo != NULL) {
1140 bzero(siginfo, sizeof(*siginfo));
1141 siginfo->si_errno = 0;
1144 * SUSv4 requires that the si_signo value is always
1145 * SIGCHLD. Obey it despite the rfork(2) interface
1146 * allows to request other signal for child exit
1149 siginfo->si_signo = SIGCHLD;
1152 * This is still a rough estimate. We will fix the
1153 * cases TRAPPED, STOPPED, and CONTINUED later.
1155 if (WCOREDUMP(p->p_xsig)) {
1156 siginfo->si_code = CLD_DUMPED;
1157 siginfo->si_status = WTERMSIG(p->p_xsig);
1158 } else if (WIFSIGNALED(p->p_xsig)) {
1159 siginfo->si_code = CLD_KILLED;
1160 siginfo->si_status = WTERMSIG(p->p_xsig);
1162 siginfo->si_code = CLD_EXITED;
1163 siginfo->si_status = p->p_xexit;
1166 siginfo->si_pid = p->p_pid;
1167 siginfo->si_uid = p->p_ucred->cr_uid;
1170 * The si_addr field would be useful additional
1171 * detail, but apparently the PC value may be lost
1172 * when we reach this point. bzero() above sets
1173 * siginfo->si_addr to NULL.
1178 * There should be no reason to limit resources usage info to
1179 * exited processes only. A snapshot about any resources used
1180 * by a stopped process may be exactly what is needed.
1182 if (wrusage != NULL) {
1183 rup = &wrusage->wru_self;
1186 calcru(p, &rup->ru_utime, &rup->ru_stime);
1189 rup = &wrusage->wru_children;
1190 *rup = p->p_stats->p_cru;
1191 calccru(p, &rup->ru_utime, &rup->ru_stime);
1194 if (p->p_state == PRS_ZOMBIE && !check_only) {
1195 proc_reap(td, p, status, options);
1202 kern_wait(struct thread *td, pid_t pid, int *status, int options,
1203 struct rusage *rusage)
1205 struct __wrusage wru, *wrup;
1211 * Translate the special pid values into the (idtype, pid)
1212 * pair for kern_wait6. The WAIT_MYPGRP case is handled by
1213 * kern_wait6() on its own.
1215 if (pid == WAIT_ANY) {
1218 } else if (pid < 0) {
1232 * For backward compatibility we implicitly add flags WEXITED
1233 * and WTRAPPED here.
1235 options |= WEXITED | WTRAPPED;
1236 ret = kern_wait6(td, idtype, id, status, options, wrup, NULL);
1238 *rusage = wru.wru_self;
1243 report_alive_proc(struct thread *td, struct proc *p, siginfo_t *siginfo,
1244 int *status, int options, int si_code)
1248 PROC_LOCK_ASSERT(p, MA_OWNED);
1249 sx_assert(&proctree_lock, SA_XLOCKED);
1250 MPASS(si_code == CLD_TRAPPED || si_code == CLD_STOPPED ||
1251 si_code == CLD_CONTINUED);
1253 cont = si_code == CLD_CONTINUED;
1254 if ((options & WNOWAIT) == 0) {
1256 p->p_flag &= ~P_CONTINUED;
1258 p->p_flag |= P_WAITED;
1259 if (kern_wait_dequeue_sigchld &&
1260 (td->td_proc->p_sysent->sv_flags & SV_SIG_WAITNDQ) == 0) {
1261 PROC_LOCK(td->td_proc);
1262 sigqueue_take(p->p_ksi);
1263 PROC_UNLOCK(td->td_proc);
1266 sx_xunlock(&proctree_lock);
1267 if (siginfo != NULL) {
1268 siginfo->si_code = si_code;
1269 siginfo->si_status = cont ? SIGCONT : p->p_xsig;
1272 *status = cont ? SIGCONT : W_STOPCODE(p->p_xsig);
1273 td->td_retval[0] = p->p_pid;
1278 kern_wait6(struct thread *td, idtype_t idtype, id_t id, int *status,
1279 int options, struct __wrusage *wrusage, siginfo_t *siginfo)
1283 int error, nfound, ret;
1286 AUDIT_ARG_VALUE((int)idtype); /* XXX - This is likely wrong! */
1287 AUDIT_ARG_PID((pid_t)id); /* XXX - This may be wrong! */
1288 AUDIT_ARG_VALUE(options);
1292 if ((pid_t)id == WAIT_MYPGRP && (idtype == P_PID || idtype == P_PGID)) {
1294 id = (id_t)q->p_pgid;
1299 /* If we don't know the option, just return. */
1300 if ((options & ~(WUNTRACED | WNOHANG | WCONTINUED | WNOWAIT |
1301 WEXITED | WTRAPPED | WLINUXCLONE)) != 0)
1303 if ((options & (WEXITED | WUNTRACED | WCONTINUED | WTRAPPED)) == 0) {
1305 * We will be unable to find any matching processes,
1306 * because there are no known events to look for.
1307 * Prefer to return error instead of blocking
1314 if (q->p_flag & P_STATCHILD) {
1316 q->p_flag &= ~P_STATCHILD;
1319 sx_xlock(&proctree_lock);
1322 LIST_FOREACH(p, &q->p_children, p_sibling) {
1324 ret = proc_to_reap(td, p, idtype, id, status, options,
1325 wrusage, siginfo, 0);
1328 else if (ret != 1) {
1329 td->td_retval[0] = pid;
1334 PROC_LOCK_ASSERT(p, MA_OWNED);
1336 if ((options & WTRAPPED) != 0 &&
1337 (p->p_flag & P_TRACED) != 0) {
1340 ((p->p_flag & (P_STOPPED_TRACE | P_STOPPED_SIG)) &&
1341 p->p_suspcount == p->p_numthreads &&
1342 (p->p_flag & P_WAITED) == 0);
1346 "wait: returning trapped pid %d status %#x "
1347 "(xstat %d) xthread %d",
1348 p->p_pid, W_STOPCODE(p->p_xsig), p->p_xsig,
1349 p->p_xthread != NULL ?
1350 p->p_xthread->td_tid : -1);
1351 report_alive_proc(td, p, siginfo, status,
1352 options, CLD_TRAPPED);
1356 if ((options & WUNTRACED) != 0 &&
1357 (p->p_flag & P_STOPPED_SIG) != 0) {
1359 report = (p->p_suspcount == p->p_numthreads &&
1360 ((p->p_flag & P_WAITED) == 0));
1363 report_alive_proc(td, p, siginfo, status,
1364 options, CLD_STOPPED);
1368 if ((options & WCONTINUED) != 0 &&
1369 (p->p_flag & P_CONTINUED) != 0) {
1370 report_alive_proc(td, p, siginfo, status, options,
1378 * Look in the orphans list too, to allow the parent to
1379 * collect it's child exit status even if child is being
1382 * Debugger detaches from the parent upon successful
1383 * switch-over from parent to child. At this point due to
1384 * re-parenting the parent loses the child to debugger and a
1385 * wait4(2) call would report that it has no children to wait
1386 * for. By maintaining a list of orphans we allow the parent
1387 * to successfully wait until the child becomes a zombie.
1390 LIST_FOREACH(p, &q->p_orphans, p_orphan) {
1391 ret = proc_to_reap(td, p, idtype, id, NULL, options,
1394 KASSERT(ret != -1, ("reaped an orphan (pid %d)",
1395 (int)td->td_retval[0]));
1403 sx_xunlock(&proctree_lock);
1406 if (options & WNOHANG) {
1407 sx_xunlock(&proctree_lock);
1408 td->td_retval[0] = 0;
1412 if (q->p_flag & P_STATCHILD) {
1413 q->p_flag &= ~P_STATCHILD;
1417 sx_xunlock(&proctree_lock);
1418 error = msleep(q, &q->p_mtx, PWAIT | PCATCH | PDROP, "wait", 0);
1425 proc_add_orphan(struct proc *child, struct proc *parent)
1428 sx_assert(&proctree_lock, SX_XLOCKED);
1429 KASSERT((child->p_flag & P_TRACED) != 0,
1430 ("proc_add_orphan: not traced"));
1432 if (LIST_EMPTY(&parent->p_orphans)) {
1433 child->p_treeflag |= P_TREE_FIRST_ORPHAN;
1434 LIST_INSERT_HEAD(&parent->p_orphans, child, p_orphan);
1436 LIST_INSERT_AFTER(LIST_FIRST(&parent->p_orphans),
1439 child->p_treeflag |= P_TREE_ORPHANED;
1443 * Make process 'parent' the new parent of process 'child'.
1444 * Must be called with an exclusive hold of proctree lock.
1447 proc_reparent(struct proc *child, struct proc *parent, bool set_oppid)
1450 sx_assert(&proctree_lock, SX_XLOCKED);
1451 PROC_LOCK_ASSERT(child, MA_OWNED);
1452 if (child->p_pptr == parent)
1455 PROC_LOCK(child->p_pptr);
1456 sigqueue_take(child->p_ksi);
1457 PROC_UNLOCK(child->p_pptr);
1458 LIST_REMOVE(child, p_sibling);
1459 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
1461 proc_clear_orphan(child);
1462 if ((child->p_flag & P_TRACED) != 0) {
1463 proc_add_orphan(child, child->p_pptr);
1466 child->p_pptr = parent;
1468 child->p_oppid = parent->p_pid;