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-rw-r--r--sys/kern/kern_exit.c1261
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diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
new file mode 100644
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--- /dev/null
+++ b/sys/kern/kern_exit.c
@@ -0,0 +1,1261 @@
+/*-
+ * Copyright (c) 1982, 1986, 1989, 1991, 1993
+ * The Regents of the University of California. All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "opt_compat.h"
+#include "opt_kdtrace.h"
+#include "opt_ktrace.h"
+#include "opt_procdesc.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/sysproto.h>
+#include <sys/capability.h>
+#include <sys/eventhandler.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/procdesc.h>
+#include <sys/pioctl.h>
+#include <sys/jail.h>
+#include <sys/tty.h>
+#include <sys/wait.h>
+#include <sys/vmmeter.h>
+#include <sys/vnode.h>
+#include <sys/racct.h>
+#include <sys/resourcevar.h>
+#include <sys/sbuf.h>
+#include <sys/signalvar.h>
+#include <sys/sched.h>
+#include <sys/sx.h>
+#include <sys/syscallsubr.h>
+#include <sys/syslog.h>
+#include <sys/ptrace.h>
+#include <sys/acct.h> /* for acct_process() function prototype */
+#include <sys/filedesc.h>
+#include <sys/sdt.h>
+#include <sys/shm.h>
+#include <sys/sem.h>
+#ifdef KTRACE
+#include <sys/ktrace.h>
+#endif
+
+#include <security/audit/audit.h>
+#include <security/mac/mac_framework.h>
+
+#include <vm/vm.h>
+#include <vm/vm_extern.h>
+#include <vm/vm_param.h>
+#include <vm/pmap.h>
+#include <vm/vm_map.h>
+#include <vm/vm_page.h>
+#include <vm/uma.h>
+
+#ifdef KDTRACE_HOOKS
+#include <sys/dtrace_bsd.h>
+dtrace_execexit_func_t dtrace_fasttrap_exit;
+#endif
+
+SDT_PROVIDER_DECLARE(proc);
+SDT_PROBE_DEFINE1(proc, kernel, , exit, exit, "int");
+
+/* Hook for NFS teardown procedure. */
+void (*nlminfo_release_p)(struct proc *p);
+
+static void
+clear_orphan(struct proc *p)
+{
+
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+
+ if (p->p_flag & P_ORPHAN) {
+ LIST_REMOVE(p, p_orphan);
+ p->p_flag &= ~P_ORPHAN;
+ }
+}
+
+/*
+ * exit -- death of process.
+ */
+void
+sys_sys_exit(struct thread *td, struct sys_exit_args *uap)
+{
+
+ exit1(td, W_EXITCODE(uap->rval, 0));
+ /* NOTREACHED */
+}
+
+/*
+ * Exit: deallocate address space and other resources, change proc state to
+ * zombie, and unlink proc from allproc and parent's lists. Save exit status
+ * and rusage for wait(). Check for child processes and orphan them.
+ */
+void
+exit1(struct thread *td, int rv)
+{
+ struct proc *p, *nq, *q;
+ struct vnode *vtmp;
+ struct vnode *ttyvp = NULL;
+ struct plimit *plim;
+
+ mtx_assert(&Giant, MA_NOTOWNED);
+
+ p = td->td_proc;
+ /*
+ * XXX in case we're rebooting we just let init die in order to
+ * work around an unsolved stack overflow seen very late during
+ * shutdown on sparc64 when the gmirror worker process exists.
+ */
+ if (p == initproc && rebooting == 0) {
+ printf("init died (signal %d, exit %d)\n",
+ WTERMSIG(rv), WEXITSTATUS(rv));
+ panic("Going nowhere without my init!");
+ }
+
+ /*
+ * MUST abort all other threads before proceeding past here.
+ */
+ PROC_LOCK(p);
+ while (p->p_flag & P_HADTHREADS) {
+ /*
+ * First check if some other thread got here before us.
+ * If so, act appropriately: exit or suspend.
+ */
+ thread_suspend_check(0);
+
+ /*
+ * Kill off the other threads. This requires
+ * some co-operation from other parts of the kernel
+ * so it may not be instantaneous. With this state set
+ * any thread entering the kernel from userspace will
+ * thread_exit() in trap(). Any thread attempting to
+ * sleep will return immediately with EINTR or EWOULDBLOCK
+ * which will hopefully force them to back out to userland
+ * freeing resources as they go. Any thread attempting
+ * to return to userland will thread_exit() from userret().
+ * thread_exit() will unsuspend us when the last of the
+ * other threads exits.
+ * If there is already a thread singler after resumption,
+ * calling thread_single will fail; in that case, we just
+ * re-check all suspension request, the thread should
+ * either be suspended there or exit.
+ */
+ if (!thread_single(SINGLE_EXIT))
+ break;
+
+ /*
+ * All other activity in this process is now stopped.
+ * Threading support has been turned off.
+ */
+ }
+ KASSERT(p->p_numthreads == 1,
+ ("exit1: proc %p exiting with %d threads", p, p->p_numthreads));
+ racct_sub(p, RACCT_NTHR, 1);
+ /*
+ * Wakeup anyone in procfs' PIOCWAIT. They should have a hold
+ * on our vmspace, so we should block below until they have
+ * released their reference to us. Note that if they have
+ * requested S_EXIT stops we will block here until they ack
+ * via PIOCCONT.
+ */
+ _STOPEVENT(p, S_EXIT, rv);
+
+ /*
+ * Ignore any pending request to stop due to a stop signal.
+ * Once P_WEXIT is set, future requests will be ignored as
+ * well.
+ */
+ p->p_flag &= ~P_STOPPED_SIG;
+ KASSERT(!P_SHOULDSTOP(p), ("exiting process is stopped"));
+
+ /*
+ * Note that we are exiting and do another wakeup of anyone in
+ * PIOCWAIT in case they aren't listening for S_EXIT stops or
+ * decided to wait again after we told them we are exiting.
+ */
+ p->p_flag |= P_WEXIT;
+ wakeup(&p->p_stype);
+
+ /*
+ * Wait for any processes that have a hold on our vmspace to
+ * release their reference.
+ */
+ while (p->p_lock > 0)
+ msleep(&p->p_lock, &p->p_mtx, PWAIT, "exithold", 0);
+
+ p->p_xstat = rv; /* Let event handler change exit status */
+ PROC_UNLOCK(p);
+ /* Drain the limit callout while we don't have the proc locked */
+ callout_drain(&p->p_limco);
+
+#ifdef AUDIT
+ /*
+ * The Sun BSM exit token contains two components: an exit status as
+ * passed to exit(), and a return value to indicate what sort of exit
+ * it was. The exit status is WEXITSTATUS(rv), but it's not clear
+ * what the return value is.
+ */
+ AUDIT_ARG_EXIT(WEXITSTATUS(rv), 0);
+ AUDIT_SYSCALL_EXIT(0, td);
+#endif
+
+ /* Are we a task leader? */
+ if (p == p->p_leader) {
+ mtx_lock(&ppeers_lock);
+ q = p->p_peers;
+ while (q != NULL) {
+ PROC_LOCK(q);
+ kern_psignal(q, SIGKILL);
+ PROC_UNLOCK(q);
+ q = q->p_peers;
+ }
+ while (p->p_peers != NULL)
+ msleep(p, &ppeers_lock, PWAIT, "exit1", 0);
+ mtx_unlock(&ppeers_lock);
+ }
+
+ /*
+ * Check if any loadable modules need anything done at process exit.
+ * E.g. SYSV IPC stuff
+ * XXX what if one of these generates an error?
+ */
+ EVENTHANDLER_INVOKE(process_exit, p);
+
+ /*
+ * If parent is waiting for us to exit or exec,
+ * P_PPWAIT is set; we will wakeup the parent below.
+ */
+ PROC_LOCK(p);
+ rv = p->p_xstat; /* Event handler could change exit status */
+ stopprofclock(p);
+ p->p_flag &= ~(P_TRACED | P_PPWAIT | P_PPTRACE);
+
+ /*
+ * Stop the real interval timer. If the handler is currently
+ * executing, prevent it from rearming itself and let it finish.
+ */
+ if (timevalisset(&p->p_realtimer.it_value) &&
+ callout_stop(&p->p_itcallout) == 0) {
+ timevalclear(&p->p_realtimer.it_interval);
+ msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0);
+ KASSERT(!timevalisset(&p->p_realtimer.it_value),
+ ("realtime timer is still armed"));
+ }
+ PROC_UNLOCK(p);
+
+ /*
+ * Reset any sigio structures pointing to us as a result of
+ * F_SETOWN with our pid.
+ */
+ funsetownlst(&p->p_sigiolst);
+
+ /*
+ * If this process has an nlminfo data area (for lockd), release it
+ */
+ if (nlminfo_release_p != NULL && p->p_nlminfo != NULL)
+ (*nlminfo_release_p)(p);
+
+ /*
+ * Close open files and release open-file table.
+ * This may block!
+ */
+ fdescfree(td);
+
+ /*
+ * If this thread tickled GEOM, we need to wait for the giggling to
+ * stop before we return to userland
+ */
+ if (td->td_pflags & TDP_GEOM)
+ g_waitidle();
+
+ /*
+ * Remove ourself from our leader's peer list and wake our leader.
+ */
+ mtx_lock(&ppeers_lock);
+ if (p->p_leader->p_peers) {
+ q = p->p_leader;
+ while (q->p_peers != p)
+ q = q->p_peers;
+ q->p_peers = p->p_peers;
+ wakeup(p->p_leader);
+ }
+ mtx_unlock(&ppeers_lock);
+
+ vmspace_exit(td);
+
+ sx_xlock(&proctree_lock);
+ if (SESS_LEADER(p)) {
+ struct session *sp = p->p_session;
+ struct tty *tp;
+
+ /*
+ * s_ttyp is not zero'd; we use this to indicate that
+ * the session once had a controlling terminal. (for
+ * logging and informational purposes)
+ */
+ SESS_LOCK(sp);
+ ttyvp = sp->s_ttyvp;
+ tp = sp->s_ttyp;
+ sp->s_ttyvp = NULL;
+ sp->s_ttydp = NULL;
+ sp->s_leader = NULL;
+ SESS_UNLOCK(sp);
+
+ /*
+ * Signal foreground pgrp and revoke access to
+ * controlling terminal if it has not been revoked
+ * already.
+ *
+ * Because the TTY may have been revoked in the mean
+ * time and could already have a new session associated
+ * with it, make sure we don't send a SIGHUP to a
+ * foreground process group that does not belong to this
+ * session.
+ */
+
+ if (tp != NULL) {
+ tty_lock(tp);
+ if (tp->t_session == sp)
+ tty_signal_pgrp(tp, SIGHUP);
+ tty_unlock(tp);
+ }
+
+ if (ttyvp != NULL) {
+ sx_xunlock(&proctree_lock);
+ if (vn_lock(ttyvp, LK_EXCLUSIVE) == 0) {
+ VOP_REVOKE(ttyvp, REVOKEALL);
+ VOP_UNLOCK(ttyvp, 0);
+ }
+ sx_xlock(&proctree_lock);
+ }
+ }
+ fixjobc(p, p->p_pgrp, 0);
+ sx_xunlock(&proctree_lock);
+ (void)acct_process(td);
+
+ /* Release the TTY now we've unlocked everything. */
+ if (ttyvp != NULL)
+ vrele(ttyvp);
+#ifdef KTRACE
+ ktrprocexit(td);
+#endif
+ /*
+ * Release reference to text vnode
+ */
+ if ((vtmp = p->p_textvp) != NULL) {
+ p->p_textvp = NULL;
+ vrele(vtmp);
+ }
+
+ /*
+ * Release our limits structure.
+ */
+ PROC_LOCK(p);
+ plim = p->p_limit;
+ p->p_limit = NULL;
+ PROC_UNLOCK(p);
+ lim_free(plim);
+
+ tidhash_remove(td);
+
+ /*
+ * Remove proc from allproc queue and pidhash chain.
+ * Place onto zombproc. Unlink from parent's child list.
+ */
+ sx_xlock(&allproc_lock);
+ LIST_REMOVE(p, p_list);
+ LIST_INSERT_HEAD(&zombproc, p, p_list);
+ LIST_REMOVE(p, p_hash);
+ sx_xunlock(&allproc_lock);
+
+ /*
+ * Call machine-dependent code to release any
+ * machine-dependent resources other than the address space.
+ * The address space is released by "vmspace_exitfree(p)" in
+ * vm_waitproc().
+ */
+ cpu_exit(td);
+
+ WITNESS_WARN(WARN_PANIC, NULL, "process (pid %d) exiting", p->p_pid);
+
+ /*
+ * Reparent all of our children to init.
+ */
+ sx_xlock(&proctree_lock);
+ q = LIST_FIRST(&p->p_children);
+ if (q != NULL) /* only need this if any child is S_ZOMB */
+ wakeup(initproc);
+ for (; q != NULL; q = nq) {
+ nq = LIST_NEXT(q, p_sibling);
+ PROC_LOCK(q);
+ proc_reparent(q, initproc);
+ q->p_sigparent = SIGCHLD;
+ /*
+ * Traced processes are killed
+ * since their existence means someone is screwing up.
+ */
+ if (q->p_flag & P_TRACED) {
+ struct thread *temp;
+
+ /*
+ * Since q was found on our children list, the
+ * proc_reparent() call moved q to the orphan
+ * list due to present P_TRACED flag. Clear
+ * orphan link for q now while q is locked.
+ */
+ clear_orphan(q);
+ q->p_flag &= ~(P_TRACED | P_STOPPED_TRACE);
+ FOREACH_THREAD_IN_PROC(q, temp)
+ temp->td_dbgflags &= ~TDB_SUSPEND;
+ kern_psignal(q, SIGKILL);
+ }
+ PROC_UNLOCK(q);
+ }
+
+ /*
+ * Also get rid of our orphans.
+ */
+ while ((q = LIST_FIRST(&p->p_orphans)) != NULL) {
+ PROC_LOCK(q);
+ clear_orphan(q);
+ PROC_UNLOCK(q);
+ }
+
+ /* Save exit status. */
+ PROC_LOCK(p);
+ p->p_xthread = td;
+
+ /* Tell the prison that we are gone. */
+ prison_proc_free(p->p_ucred->cr_prison);
+
+#ifdef KDTRACE_HOOKS
+ /*
+ * Tell the DTrace fasttrap provider about the exit if it
+ * has declared an interest.
+ */
+ if (dtrace_fasttrap_exit)
+ dtrace_fasttrap_exit(p);
+#endif
+
+ /*
+ * Notify interested parties of our demise.
+ */
+ KNOTE_LOCKED(&p->p_klist, NOTE_EXIT);
+
+#ifdef KDTRACE_HOOKS
+ int reason = CLD_EXITED;
+ if (WCOREDUMP(rv))
+ reason = CLD_DUMPED;
+ else if (WIFSIGNALED(rv))
+ reason = CLD_KILLED;
+ SDT_PROBE(proc, kernel, , exit, reason, 0, 0, 0, 0);
+#endif
+
+ /*
+ * Just delete all entries in the p_klist. At this point we won't
+ * report any more events, and there are nasty race conditions that
+ * can beat us if we don't.
+ */
+ knlist_clear(&p->p_klist, 1);
+
+ /*
+ * If this is a process with a descriptor, we may not need to deliver
+ * a signal to the parent. proctree_lock is held over
+ * procdesc_exit() to serialize concurrent calls to close() and
+ * exit().
+ */
+#ifdef PROCDESC
+ if (p->p_procdesc == NULL || procdesc_exit(p)) {
+#endif
+ /*
+ * Notify parent that we're gone. If parent has the
+ * PS_NOCLDWAIT flag set, or if the handler is set to SIG_IGN,
+ * notify process 1 instead (and hope it will handle this
+ * situation).
+ */
+ PROC_LOCK(p->p_pptr);
+ mtx_lock(&p->p_pptr->p_sigacts->ps_mtx);
+ if (p->p_pptr->p_sigacts->ps_flag &
+ (PS_NOCLDWAIT | PS_CLDSIGIGN)) {
+ struct proc *pp;
+
+ mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
+ pp = p->p_pptr;
+ PROC_UNLOCK(pp);
+ proc_reparent(p, initproc);
+ p->p_sigparent = SIGCHLD;
+ PROC_LOCK(p->p_pptr);
+
+ /*
+ * Notify parent, so in case he was wait(2)ing or
+ * executing waitpid(2) with our pid, he will
+ * continue.
+ */
+ wakeup(pp);
+ } else
+ mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
+
+ if (p->p_pptr == initproc)
+ kern_psignal(p->p_pptr, SIGCHLD);
+ else if (p->p_sigparent != 0) {
+ if (p->p_sigparent == SIGCHLD)
+ childproc_exited(p);
+ else /* LINUX thread */
+ kern_psignal(p->p_pptr, p->p_sigparent);
+ }
+#ifdef PROCDESC
+ } else
+ PROC_LOCK(p->p_pptr);
+#endif
+ sx_xunlock(&proctree_lock);
+
+ /*
+ * The state PRS_ZOMBIE prevents other proesses from sending
+ * signal to the process, to avoid memory leak, we free memory
+ * for signal queue at the time when the state is set.
+ */
+ sigqueue_flush(&p->p_sigqueue);
+ sigqueue_flush(&td->td_sigqueue);
+
+ /*
+ * We have to wait until after acquiring all locks before
+ * changing p_state. We need to avoid all possible context
+ * switches (including ones from blocking on a mutex) while
+ * marked as a zombie. We also have to set the zombie state
+ * before we release the parent process' proc lock to avoid
+ * a lost wakeup. So, we first call wakeup, then we grab the
+ * sched lock, update the state, and release the parent process'
+ * proc lock.
+ */
+ wakeup(p->p_pptr);
+ cv_broadcast(&p->p_pwait);
+ sched_exit(p->p_pptr, td);
+ PROC_SLOCK(p);
+ p->p_state = PRS_ZOMBIE;
+ PROC_UNLOCK(p->p_pptr);
+
+ /*
+ * Hopefully no one will try to deliver a signal to the process this
+ * late in the game.
+ */
+ knlist_destroy(&p->p_klist);
+
+ /*
+ * Save our children's rusage information in our exit rusage.
+ */
+ ruadd(&p->p_ru, &p->p_rux, &p->p_stats->p_cru, &p->p_crux);
+
+ /*
+ * Make sure the scheduler takes this thread out of its tables etc.
+ * This will also release this thread's reference to the ucred.
+ * Other thread parts to release include pcb bits and such.
+ */
+ thread_exit();
+}
+
+
+#ifndef _SYS_SYSPROTO_H_
+struct abort2_args {
+ char *why;
+ int nargs;
+ void **args;
+};
+#endif
+
+int
+sys_abort2(struct thread *td, struct abort2_args *uap)
+{
+ struct proc *p = td->td_proc;
+ struct sbuf *sb;
+ void *uargs[16];
+ int error, i, sig;
+
+ /*
+ * Do it right now so we can log either proper call of abort2(), or
+ * note, that invalid argument was passed. 512 is big enough to
+ * handle 16 arguments' descriptions with additional comments.
+ */
+ sb = sbuf_new(NULL, NULL, 512, SBUF_FIXEDLEN);
+ sbuf_clear(sb);
+ sbuf_printf(sb, "%s(pid %d uid %d) aborted: ",
+ p->p_comm, p->p_pid, td->td_ucred->cr_uid);
+ /*
+ * Since we can't return from abort2(), send SIGKILL in cases, where
+ * abort2() was called improperly
+ */
+ sig = SIGKILL;
+ /* Prevent from DoSes from user-space. */
+ if (uap->nargs < 0 || uap->nargs > 16)
+ goto out;
+ if (uap->nargs > 0) {
+ if (uap->args == NULL)
+ goto out;
+ error = copyin(uap->args, uargs, uap->nargs * sizeof(void *));
+ if (error != 0)
+ goto out;
+ }
+ /*
+ * Limit size of 'reason' string to 128. Will fit even when
+ * maximal number of arguments was chosen to be logged.
+ */
+ if (uap->why != NULL) {
+ error = sbuf_copyin(sb, uap->why, 128);
+ if (error < 0)
+ goto out;
+ } else {
+ sbuf_printf(sb, "(null)");
+ }
+ if (uap->nargs > 0) {
+ sbuf_printf(sb, "(");
+ for (i = 0;i < uap->nargs; i++)
+ sbuf_printf(sb, "%s%p", i == 0 ? "" : ", ", uargs[i]);
+ sbuf_printf(sb, ")");
+ }
+ /*
+ * Final stage: arguments were proper, string has been
+ * successfully copied from userspace, and copying pointers
+ * from user-space succeed.
+ */
+ sig = SIGABRT;
+out:
+ if (sig == SIGKILL) {
+ sbuf_trim(sb);
+ sbuf_printf(sb, " (Reason text inaccessible)");
+ }
+ sbuf_cat(sb, "\n");
+ sbuf_finish(sb);
+ log(LOG_INFO, "%s", sbuf_data(sb));
+ sbuf_delete(sb);
+ exit1(td, W_EXITCODE(0, sig));
+ return (0);
+}
+
+
+#ifdef COMPAT_43
+/*
+ * The dirty work is handled by kern_wait().
+ */
+int
+owait(struct thread *td, struct owait_args *uap __unused)
+{
+ int error, status;
+
+ error = kern_wait(td, WAIT_ANY, &status, 0, NULL);
+ if (error == 0)
+ td->td_retval[1] = status;
+ return (error);
+}
+#endif /* COMPAT_43 */
+
+/*
+ * The dirty work is handled by kern_wait().
+ */
+int
+sys_wait4(struct thread *td, struct wait4_args *uap)
+{
+ struct rusage ru, *rup;
+ int error, status;
+
+ if (uap->rusage != NULL)
+ rup = &ru;
+ else
+ rup = NULL;
+ error = kern_wait(td, uap->pid, &status, uap->options, rup);
+ if (uap->status != NULL && error == 0)
+ error = copyout(&status, uap->status, sizeof(status));
+ if (uap->rusage != NULL && error == 0)
+ error = copyout(&ru, uap->rusage, sizeof(struct rusage));
+ return (error);
+}
+
+int
+sys_wait6(struct thread *td, struct wait6_args *uap)
+{
+ struct __wrusage wru, *wrup;
+ siginfo_t si, *sip;
+ idtype_t idtype;
+ id_t id;
+ int error, status;
+
+ idtype = uap->idtype;
+ id = uap->id;
+
+ if (uap->wrusage != NULL)
+ wrup = &wru;
+ else
+ wrup = NULL;
+
+ if (uap->info != NULL) {
+ sip = &si;
+ bzero(sip, sizeof(*sip));
+ } else
+ sip = NULL;
+
+ /*
+ * We expect all callers of wait6() to know about WEXITED and
+ * WTRAPPED.
+ */
+ error = kern_wait6(td, idtype, id, &status, uap->options, wrup, sip);
+
+ if (uap->status != NULL && error == 0)
+ error = copyout(&status, uap->status, sizeof(status));
+ if (uap->wrusage != NULL && error == 0)
+ error = copyout(&wru, uap->wrusage, sizeof(wru));
+ if (uap->info != NULL && error == 0)
+ error = copyout(&si, uap->info, sizeof(si));
+ return (error);
+}
+
+/*
+ * Reap the remains of a zombie process and optionally return status and
+ * rusage. Asserts and will release both the proctree_lock and the process
+ * lock as part of its work.
+ */
+void
+proc_reap(struct thread *td, struct proc *p, int *status, int options)
+{
+ struct proc *q, *t;
+
+ sx_assert(&proctree_lock, SA_XLOCKED);
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+ PROC_SLOCK_ASSERT(p, MA_OWNED);
+ KASSERT(p->p_state == PRS_ZOMBIE, ("proc_reap: !PRS_ZOMBIE"));
+
+ q = td->td_proc;
+
+ PROC_SUNLOCK(p);
+ td->td_retval[0] = p->p_pid;
+ if (status)
+ *status = p->p_xstat; /* convert to int */
+ if (options & WNOWAIT) {
+ /*
+ * Only poll, returning the status. Caller does not wish to
+ * release the proc struct just yet.
+ */
+ PROC_UNLOCK(p);
+ sx_xunlock(&proctree_lock);
+ return;
+ }
+
+ PROC_LOCK(q);
+ sigqueue_take(p->p_ksi);
+ PROC_UNLOCK(q);
+ PROC_UNLOCK(p);
+
+ /*
+ * If we got the child via a ptrace 'attach', we need to give it back
+ * to the old parent.
+ */
+ if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) {
+ PROC_LOCK(p);
+ proc_reparent(p, t);
+ p->p_oppid = 0;
+ PROC_UNLOCK(p);
+ pksignal(t, SIGCHLD, p->p_ksi);
+ wakeup(t);
+ cv_broadcast(&p->p_pwait);
+ PROC_UNLOCK(t);
+ sx_xunlock(&proctree_lock);
+ return;
+ }
+
+ /*
+ * Remove other references to this process to ensure we have an
+ * exclusive reference.
+ */
+ sx_xlock(&allproc_lock);
+ LIST_REMOVE(p, p_list); /* off zombproc */
+ sx_xunlock(&allproc_lock);
+ LIST_REMOVE(p, p_sibling);
+ PROC_LOCK(p);
+ clear_orphan(p);
+ PROC_UNLOCK(p);
+ leavepgrp(p);
+#ifdef PROCDESC
+ if (p->p_procdesc != NULL)
+ procdesc_reap(p);
+#endif
+ sx_xunlock(&proctree_lock);
+
+ /*
+ * As a side effect of this lock, we know that all other writes to
+ * this proc are visible now, so no more locking is needed for p.
+ */
+ PROC_LOCK(p);
+ p->p_xstat = 0; /* XXX: why? */
+ PROC_UNLOCK(p);
+ PROC_LOCK(q);
+ ruadd(&q->p_stats->p_cru, &q->p_crux, &p->p_ru, &p->p_rux);
+ PROC_UNLOCK(q);
+
+ /*
+ * Decrement the count of procs running with this uid.
+ */
+ (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0);
+
+ /*
+ * Destroy resource accounting information associated with the process.
+ */
+#ifdef RACCT
+ PROC_LOCK(p);
+ racct_sub(p, RACCT_NPROC, 1);
+ PROC_UNLOCK(p);
+#endif
+ racct_proc_exit(p);
+
+ /*
+ * Free credentials, arguments, and sigacts.
+ */
+ crfree(p->p_ucred);
+ p->p_ucred = NULL;
+ pargs_drop(p->p_args);
+ p->p_args = NULL;
+ sigacts_free(p->p_sigacts);
+ p->p_sigacts = NULL;
+
+ /*
+ * Do any thread-system specific cleanups.
+ */
+ thread_wait(p);
+
+ /*
+ * Give vm and machine-dependent layer a chance to free anything that
+ * cpu_exit couldn't release while still running in process context.
+ */
+ vm_waitproc(p);
+#ifdef MAC
+ mac_proc_destroy(p);
+#endif
+ KASSERT(FIRST_THREAD_IN_PROC(p),
+ ("proc_reap: no residual thread!"));
+ uma_zfree(proc_zone, p);
+ sx_xlock(&allproc_lock);
+ nprocs--;
+ sx_xunlock(&allproc_lock);
+}
+
+static int
+proc_to_reap(struct thread *td, struct proc *p, idtype_t idtype, id_t id,
+ int *status, int options, struct __wrusage *wrusage, siginfo_t *siginfo)
+{
+ struct proc *q;
+ struct rusage *rup;
+
+ sx_assert(&proctree_lock, SA_XLOCKED);
+
+ q = td->td_proc;
+ PROC_LOCK(p);
+
+ switch (idtype) {
+ case P_ALL:
+ break;
+ case P_PID:
+ if (p->p_pid != (pid_t)id) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ break;
+ case P_PGID:
+ if (p->p_pgid != (pid_t)id) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ break;
+ case P_SID:
+ if (p->p_session->s_sid != (pid_t)id) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ break;
+ case P_UID:
+ if (p->p_ucred->cr_uid != (uid_t)id) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ break;
+ case P_GID:
+ if (p->p_ucred->cr_gid != (gid_t)id) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ break;
+ case P_JAILID:
+ if (p->p_ucred->cr_prison->pr_id != (int)id) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ break;
+ /*
+ * It seems that the thread structures get zeroed out
+ * at process exit. This makes it impossible to
+ * support P_SETID, P_CID or P_CPUID.
+ */
+ default:
+ PROC_UNLOCK(p);
+ return (0);
+ }
+
+ if (p_canwait(td, p)) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+
+ if (((options & WEXITED) == 0) && (p->p_state == PRS_ZOMBIE)) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+
+ /*
+ * This special case handles a kthread spawned by linux_clone
+ * (see linux_misc.c). The linux_wait4 and linux_waitpid
+ * functions need to be able to distinguish between waiting
+ * on a process and waiting on a thread. It is a thread if
+ * p_sigparent is not SIGCHLD, and the WLINUXCLONE option
+ * signifies we want to wait for threads and not processes.
+ */
+ if ((p->p_sigparent != SIGCHLD) ^
+ ((options & WLINUXCLONE) != 0)) {
+ PROC_UNLOCK(p);
+ return (0);
+ }
+
+ PROC_SLOCK(p);
+
+ if (siginfo != NULL) {
+ bzero(siginfo, sizeof(*siginfo));
+ siginfo->si_errno = 0;
+
+ /*
+ * SUSv4 requires that the si_signo value is always
+ * SIGCHLD. Obey it despite the rfork(2) interface
+ * allows to request other signal for child exit
+ * notification.
+ */
+ siginfo->si_signo = SIGCHLD;
+
+ /*
+ * This is still a rough estimate. We will fix the
+ * cases TRAPPED, STOPPED, and CONTINUED later.
+ */
+ if (WCOREDUMP(p->p_xstat))
+ siginfo->si_code = CLD_DUMPED;
+ else if (WIFSIGNALED(p->p_xstat))
+ siginfo->si_code = CLD_KILLED;
+ else
+ siginfo->si_code = CLD_EXITED;
+
+ siginfo->si_pid = p->p_pid;
+ siginfo->si_uid = p->p_ucred->cr_uid;
+ siginfo->si_status = p->p_xstat;
+
+ /*
+ * The si_addr field would be useful additional
+ * detail, but apparently the PC value may be lost
+ * when we reach this point. bzero() above sets
+ * siginfo->si_addr to NULL.
+ */
+ }
+
+ /*
+ * There should be no reason to limit resources usage info to
+ * exited processes only. A snapshot about any resources used
+ * by a stopped process may be exactly what is needed.
+ */
+ if (wrusage != NULL) {
+ rup = &wrusage->wru_self;
+ *rup = p->p_ru;
+ calcru(p, &rup->ru_utime, &rup->ru_stime);
+
+ rup = &wrusage->wru_children;
+ *rup = p->p_stats->p_cru;
+ calccru(p, &rup->ru_utime, &rup->ru_stime);
+ }
+
+ if (p->p_state == PRS_ZOMBIE) {
+ proc_reap(td, p, status, options);
+ return (-1);
+ }
+ PROC_SUNLOCK(p);
+ PROC_UNLOCK(p);
+ return (1);
+}
+
+int
+kern_wait(struct thread *td, pid_t pid, int *status, int options,
+ struct rusage *rusage)
+{
+ struct __wrusage wru, *wrup;
+ idtype_t idtype;
+ id_t id;
+ int ret;
+
+ /*
+ * Translate the special pid values into the (idtype, pid)
+ * pair for kern_wait6. The WAIT_MYPGRP case is handled by
+ * kern_wait6() on its own.
+ */
+ if (pid == WAIT_ANY) {
+ idtype = P_ALL;
+ id = 0;
+ } else if (pid < 0) {
+ idtype = P_PGID;
+ id = (id_t)-pid;
+ } else {
+ idtype = P_PID;
+ id = (id_t)pid;
+ }
+
+ if (rusage != NULL)
+ wrup = &wru;
+ else
+ wrup = NULL;
+
+ /*
+ * For backward compatibility we implicitly add flags WEXITED
+ * and WTRAPPED here.
+ */
+ options |= WEXITED | WTRAPPED;
+ ret = kern_wait6(td, idtype, id, status, options, wrup, NULL);
+ if (rusage != NULL)
+ *rusage = wru.wru_self;
+ return (ret);
+}
+
+int
+kern_wait6(struct thread *td, idtype_t idtype, id_t id, int *status,
+ int options, struct __wrusage *wrusage, siginfo_t *siginfo)
+{
+ struct proc *p, *q;
+ int error, nfound, ret;
+
+ AUDIT_ARG_VALUE((int)idtype); /* XXX - This is likely wrong! */
+ AUDIT_ARG_PID((pid_t)id); /* XXX - This may be wrong! */
+ AUDIT_ARG_VALUE(options);
+
+ q = td->td_proc;
+
+ if ((pid_t)id == WAIT_MYPGRP && (idtype == P_PID || idtype == P_PGID)) {
+ PROC_LOCK(q);
+ id = (id_t)q->p_pgid;
+ PROC_UNLOCK(q);
+ idtype = P_PGID;
+ }
+
+ /* If we don't know the option, just return. */
+ if ((options & ~(WUNTRACED | WNOHANG | WCONTINUED | WNOWAIT |
+ WEXITED | WTRAPPED | WLINUXCLONE)) != 0)
+ return (EINVAL);
+ if ((options & (WEXITED | WUNTRACED | WCONTINUED | WTRAPPED)) == 0) {
+ /*
+ * We will be unable to find any matching processes,
+ * because there are no known events to look for.
+ * Prefer to return error instead of blocking
+ * indefinitely.
+ */
+ return (EINVAL);
+ }
+
+loop:
+ if (q->p_flag & P_STATCHILD) {
+ PROC_LOCK(q);
+ q->p_flag &= ~P_STATCHILD;
+ PROC_UNLOCK(q);
+ }
+ nfound = 0;
+ sx_xlock(&proctree_lock);
+ LIST_FOREACH(p, &q->p_children, p_sibling) {
+ ret = proc_to_reap(td, p, idtype, id, status, options,
+ wrusage, siginfo);
+ if (ret == 0)
+ continue;
+ else if (ret == 1)
+ nfound++;
+ else
+ return (0);
+
+ PROC_LOCK(p);
+ PROC_SLOCK(p);
+
+ if ((options & WTRAPPED) != 0 &&
+ (p->p_flag & P_TRACED) != 0 &&
+ (p->p_flag & (P_STOPPED_TRACE | P_STOPPED_SIG)) != 0 &&
+ (p->p_suspcount == p->p_numthreads) &&
+ ((p->p_flag & P_WAITED) == 0)) {
+ PROC_SUNLOCK(p);
+ if ((options & WNOWAIT) == 0)
+ p->p_flag |= P_WAITED;
+ sx_xunlock(&proctree_lock);
+ td->td_retval[0] = p->p_pid;
+
+ if (status != NULL)
+ *status = W_STOPCODE(p->p_xstat);
+ if (siginfo != NULL) {
+ siginfo->si_status = p->p_xstat;
+ siginfo->si_code = CLD_TRAPPED;
+ }
+ if ((options & WNOWAIT) == 0) {
+ PROC_LOCK(q);
+ sigqueue_take(p->p_ksi);
+ PROC_UNLOCK(q);
+ }
+
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ if ((options & WUNTRACED) != 0 &&
+ (p->p_flag & P_STOPPED_SIG) != 0 &&
+ (p->p_suspcount == p->p_numthreads) &&
+ ((p->p_flag & P_WAITED) == 0)) {
+ PROC_SUNLOCK(p);
+ if ((options & WNOWAIT) == 0)
+ p->p_flag |= P_WAITED;
+ sx_xunlock(&proctree_lock);
+ td->td_retval[0] = p->p_pid;
+
+ if (status != NULL)
+ *status = W_STOPCODE(p->p_xstat);
+ if (siginfo != NULL) {
+ siginfo->si_status = p->p_xstat;
+ siginfo->si_code = CLD_STOPPED;
+ }
+ if ((options & WNOWAIT) == 0) {
+ PROC_LOCK(q);
+ sigqueue_take(p->p_ksi);
+ PROC_UNLOCK(q);
+ }
+
+ PROC_UNLOCK(p);
+ return (0);
+ }
+ PROC_SUNLOCK(p);
+ if ((options & WCONTINUED) != 0 &&
+ (p->p_flag & P_CONTINUED) != 0) {
+ sx_xunlock(&proctree_lock);
+ td->td_retval[0] = p->p_pid;
+ if ((options & WNOWAIT) == 0) {
+ p->p_flag &= ~P_CONTINUED;
+ PROC_LOCK(q);
+ sigqueue_take(p->p_ksi);
+ PROC_UNLOCK(q);
+ }
+ PROC_UNLOCK(p);
+
+ if (status != NULL)
+ *status = SIGCONT;
+ if (siginfo != NULL) {
+ siginfo->si_status = SIGCONT;
+ siginfo->si_code = CLD_CONTINUED;
+ }
+ return (0);
+ }
+ PROC_UNLOCK(p);
+ }
+
+ /*
+ * Look in the orphans list too, to allow the parent to
+ * collect it's child exit status even if child is being
+ * debugged.
+ *
+ * Debugger detaches from the parent upon successful
+ * switch-over from parent to child. At this point due to
+ * re-parenting the parent loses the child to debugger and a
+ * wait4(2) call would report that it has no children to wait
+ * for. By maintaining a list of orphans we allow the parent
+ * to successfully wait until the child becomes a zombie.
+ */
+ LIST_FOREACH(p, &q->p_orphans, p_orphan) {
+ ret = proc_to_reap(td, p, idtype, id, status, options,
+ wrusage, siginfo);
+ if (ret == 0)
+ continue;
+ else if (ret == 1)
+ nfound++;
+ else
+ return (0);
+ }
+ if (nfound == 0) {
+ sx_xunlock(&proctree_lock);
+ return (ECHILD);
+ }
+ if (options & WNOHANG) {
+ sx_xunlock(&proctree_lock);
+ td->td_retval[0] = 0;
+ return (0);
+ }
+ PROC_LOCK(q);
+ sx_xunlock(&proctree_lock);
+ if (q->p_flag & P_STATCHILD) {
+ q->p_flag &= ~P_STATCHILD;
+ error = 0;
+ } else
+ error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0);
+ PROC_UNLOCK(q);
+ if (error)
+ return (error);
+ goto loop;
+}
+
+/*
+ * Make process 'parent' the new parent of process 'child'.
+ * Must be called with an exclusive hold of proctree lock.
+ */
+void
+proc_reparent(struct proc *child, struct proc *parent)
+{
+
+ sx_assert(&proctree_lock, SX_XLOCKED);
+ PROC_LOCK_ASSERT(child, MA_OWNED);
+ if (child->p_pptr == parent)
+ return;
+
+ PROC_LOCK(child->p_pptr);
+ sigqueue_take(child->p_ksi);
+ PROC_UNLOCK(child->p_pptr);
+ LIST_REMOVE(child, p_sibling);
+ LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
+
+ clear_orphan(child);
+ if (child->p_flag & P_TRACED) {
+ LIST_INSERT_HEAD(&child->p_pptr->p_orphans, child, p_orphan);
+ child->p_flag |= P_ORPHAN;
+ }
+
+ child->p_pptr = parent;
+}
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