1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 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. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include "opt_ddb.h" 43 #include "opt_ktrace.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/sysproto.h> 48 #include <sys/capsicum.h> 49 #include <sys/eventhandler.h> 50 #include <sys/kernel.h> 51 #include <sys/ktr.h> 52 #include <sys/malloc.h> 53 #include <sys/lock.h> 54 #include <sys/mutex.h> 55 #include <sys/proc.h> 56 #include <sys/procdesc.h> 57 #include <sys/jail.h> 58 #include <sys/tty.h> 59 #include <sys/wait.h> 60 #include <sys/vmmeter.h> 61 #include <sys/vnode.h> 62 #include <sys/racct.h> 63 #include <sys/resourcevar.h> 64 #include <sys/sbuf.h> 65 #include <sys/signalvar.h> 66 #include <sys/sched.h> 67 #include <sys/sx.h> 68 #include <sys/syscallsubr.h> 69 #include <sys/syslog.h> 70 #include <sys/ptrace.h> 71 #include <sys/acct.h> /* for acct_process() function prototype */ 72 #include <sys/filedesc.h> 73 #include <sys/sdt.h> 74 #include <sys/shm.h> 75 #include <sys/sem.h> 76 #include <sys/sysent.h> 77 #include <sys/timers.h> 78 #include <sys/umtx.h> 79 #ifdef KTRACE 80 #include <sys/ktrace.h> 81 #endif 82 83 #include <security/audit/audit.h> 84 #include <security/mac/mac_framework.h> 85 86 #include <vm/vm.h> 87 #include <vm/vm_extern.h> 88 #include <vm/vm_param.h> 89 #include <vm/pmap.h> 90 #include <vm/vm_map.h> 91 #include <vm/vm_page.h> 92 #include <vm/uma.h> 93 94 #ifdef KDTRACE_HOOKS 95 #include <sys/dtrace_bsd.h> 96 dtrace_execexit_func_t dtrace_fasttrap_exit; 97 #endif 98 99 SDT_PROVIDER_DECLARE(proc); 100 SDT_PROBE_DEFINE1(proc, , , exit, "int"); 101 102 struct proc * 103 proc_realparent(struct proc *child) 104 { 105 struct proc *p, *parent; 106 107 sx_assert(&proctree_lock, SX_LOCKED); 108 if ((child->p_treeflag & P_TREE_ORPHANED) == 0) 109 return (child->p_pptr->p_pid == child->p_oppid ? 110 child->p_pptr : child->p_reaper); 111 for (p = child; (p->p_treeflag & P_TREE_FIRST_ORPHAN) == 0;) { 112 /* Cannot use LIST_PREV(), since the list head is not known. */ 113 p = __containerof(p->p_orphan.le_prev, struct proc, 114 p_orphan.le_next); 115 KASSERT((p->p_treeflag & P_TREE_ORPHANED) != 0, 116 ("missing P_ORPHAN %p", p)); 117 } 118 parent = __containerof(p->p_orphan.le_prev, struct proc, 119 p_orphans.lh_first); 120 return (parent); 121 } 122 123 void 124 reaper_abandon_children(struct proc *p, bool exiting) 125 { 126 struct proc *p1, *p2, *ptmp; 127 128 sx_assert(&proctree_lock, SX_LOCKED); 129 KASSERT(p != initproc, ("reaper_abandon_children for initproc")); 130 if ((p->p_treeflag & P_TREE_REAPER) == 0) 131 return; 132 p1 = p->p_reaper; 133 LIST_FOREACH_SAFE(p2, &p->p_reaplist, p_reapsibling, ptmp) { 134 LIST_REMOVE(p2, p_reapsibling); 135 p2->p_reaper = p1; 136 p2->p_reapsubtree = p->p_reapsubtree; 137 LIST_INSERT_HEAD(&p1->p_reaplist, p2, p_reapsibling); 138 if (exiting && p2->p_pptr == p) { 139 PROC_LOCK(p2); 140 proc_reparent(p2, p1, true); 141 PROC_UNLOCK(p2); 142 } 143 } 144 KASSERT(LIST_EMPTY(&p->p_reaplist), ("p_reaplist not empty")); 145 p->p_treeflag &= ~P_TREE_REAPER; 146 } 147 148 static void 149 reaper_clear(struct proc *p) 150 { 151 struct proc *p1; 152 bool clear; 153 154 sx_assert(&proctree_lock, SX_LOCKED); 155 LIST_REMOVE(p, p_reapsibling); 156 if (p->p_reapsubtree == 1) 157 return; 158 clear = true; 159 LIST_FOREACH(p1, &p->p_reaper->p_reaplist, p_reapsibling) { 160 if (p1->p_reapsubtree == p->p_reapsubtree) { 161 clear = false; 162 break; 163 } 164 } 165 if (clear) 166 proc_id_clear(PROC_ID_REAP, p->p_reapsubtree); 167 } 168 169 void 170 proc_clear_orphan(struct proc *p) 171 { 172 struct proc *p1; 173 174 sx_assert(&proctree_lock, SA_XLOCKED); 175 if ((p->p_treeflag & P_TREE_ORPHANED) == 0) 176 return; 177 if ((p->p_treeflag & P_TREE_FIRST_ORPHAN) != 0) { 178 p1 = LIST_NEXT(p, p_orphan); 179 if (p1 != NULL) 180 p1->p_treeflag |= P_TREE_FIRST_ORPHAN; 181 p->p_treeflag &= ~P_TREE_FIRST_ORPHAN; 182 } 183 LIST_REMOVE(p, p_orphan); 184 p->p_treeflag &= ~P_TREE_ORPHANED; 185 } 186 187 /* 188 * exit -- death of process. 189 */ 190 void 191 sys_sys_exit(struct thread *td, struct sys_exit_args *uap) 192 { 193 194 exit1(td, uap->rval, 0); 195 /* NOTREACHED */ 196 } 197 198 /* 199 * Exit: deallocate address space and other resources, change proc state to 200 * zombie, and unlink proc from allproc and parent's lists. Save exit status 201 * and rusage for wait(). Check for child processes and orphan them. 202 */ 203 void 204 exit1(struct thread *td, int rval, int signo) 205 { 206 struct proc *p, *nq, *q, *t; 207 struct thread *tdt; 208 ksiginfo_t *ksi, *ksi1; 209 int signal_parent; 210 211 mtx_assert(&Giant, MA_NOTOWNED); 212 KASSERT(rval == 0 || signo == 0, ("exit1 rv %d sig %d", rval, signo)); 213 214 p = td->td_proc; 215 /* 216 * XXX in case we're rebooting we just let init die in order to 217 * work around an unsolved stack overflow seen very late during 218 * shutdown on sparc64 when the gmirror worker process exists. 219 * XXX what to do now that sparc64 is gone... remove if? 220 */ 221 if (p == initproc && rebooting == 0) { 222 printf("init died (signal %d, exit %d)\n", signo, rval); 223 panic("Going nowhere without my init!"); 224 } 225 226 /* 227 * Deref SU mp, since the thread does not return to userspace. 228 */ 229 td_softdep_cleanup(td); 230 231 /* 232 * MUST abort all other threads before proceeding past here. 233 */ 234 PROC_LOCK(p); 235 /* 236 * First check if some other thread or external request got 237 * here before us. If so, act appropriately: exit or suspend. 238 * We must ensure that stop requests are handled before we set 239 * P_WEXIT. 240 */ 241 thread_suspend_check(0); 242 while (p->p_flag & P_HADTHREADS) { 243 /* 244 * Kill off the other threads. This requires 245 * some co-operation from other parts of the kernel 246 * so it may not be instantaneous. With this state set 247 * any thread entering the kernel from userspace will 248 * thread_exit() in trap(). Any thread attempting to 249 * sleep will return immediately with EINTR or EWOULDBLOCK 250 * which will hopefully force them to back out to userland 251 * freeing resources as they go. Any thread attempting 252 * to return to userland will thread_exit() from userret(). 253 * thread_exit() will unsuspend us when the last of the 254 * other threads exits. 255 * If there is already a thread singler after resumption, 256 * calling thread_single will fail; in that case, we just 257 * re-check all suspension request, the thread should 258 * either be suspended there or exit. 259 */ 260 if (!thread_single(p, SINGLE_EXIT)) 261 /* 262 * All other activity in this process is now 263 * stopped. Threading support has been turned 264 * off. 265 */ 266 break; 267 /* 268 * Recheck for new stop or suspend requests which 269 * might appear while process lock was dropped in 270 * thread_single(). 271 */ 272 thread_suspend_check(0); 273 } 274 KASSERT(p->p_numthreads == 1, 275 ("exit1: proc %p exiting with %d threads", p, p->p_numthreads)); 276 racct_sub(p, RACCT_NTHR, 1); 277 278 /* Let event handler change exit status */ 279 p->p_xexit = rval; 280 p->p_xsig = signo; 281 282 /* 283 * Ignore any pending request to stop due to a stop signal. 284 * Once P_WEXIT is set, future requests will be ignored as 285 * well. 286 */ 287 p->p_flag &= ~P_STOPPED_SIG; 288 KASSERT(!P_SHOULDSTOP(p), ("exiting process is stopped")); 289 290 /* Note that we are exiting. */ 291 p->p_flag |= P_WEXIT; 292 293 /* 294 * Wait for any processes that have a hold on our vmspace to 295 * release their reference. 296 */ 297 while (p->p_lock > 0) 298 msleep(&p->p_lock, &p->p_mtx, PWAIT, "exithold", 0); 299 300 PROC_UNLOCK(p); 301 /* Drain the limit callout while we don't have the proc locked */ 302 callout_drain(&p->p_limco); 303 304 #ifdef AUDIT 305 /* 306 * The Sun BSM exit token contains two components: an exit status as 307 * passed to exit(), and a return value to indicate what sort of exit 308 * it was. The exit status is WEXITSTATUS(rv), but it's not clear 309 * what the return value is. 310 */ 311 AUDIT_ARG_EXIT(rval, 0); 312 AUDIT_SYSCALL_EXIT(0, td); 313 #endif 314 315 /* Are we a task leader with peers? */ 316 if (p->p_peers != NULL && p == p->p_leader) { 317 mtx_lock(&ppeers_lock); 318 q = p->p_peers; 319 while (q != NULL) { 320 PROC_LOCK(q); 321 kern_psignal(q, SIGKILL); 322 PROC_UNLOCK(q); 323 q = q->p_peers; 324 } 325 while (p->p_peers != NULL) 326 msleep(p, &ppeers_lock, PWAIT, "exit1", 0); 327 mtx_unlock(&ppeers_lock); 328 } 329 330 itimers_exit(p); 331 332 if (p->p_sysent->sv_onexit != NULL) 333 p->p_sysent->sv_onexit(p); 334 335 /* 336 * Check if any loadable modules need anything done at process exit. 337 * E.g. SYSV IPC stuff. 338 * Event handler could change exit status. 339 * XXX what if one of these generates an error? 340 */ 341 EVENTHANDLER_DIRECT_INVOKE(process_exit, p); 342 343 /* 344 * If parent is waiting for us to exit or exec, 345 * P_PPWAIT is set; we will wakeup the parent below. 346 */ 347 PROC_LOCK(p); 348 stopprofclock(p); 349 p->p_ptevents = 0; 350 351 /* 352 * Stop the real interval timer. If the handler is currently 353 * executing, prevent it from rearming itself and let it finish. 354 */ 355 if (timevalisset(&p->p_realtimer.it_value) && 356 _callout_stop_safe(&p->p_itcallout, CS_EXECUTING, NULL) == 0) { 357 timevalclear(&p->p_realtimer.it_interval); 358 msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0); 359 KASSERT(!timevalisset(&p->p_realtimer.it_value), 360 ("realtime timer is still armed")); 361 } 362 363 PROC_UNLOCK(p); 364 365 umtx_thread_exit(td); 366 seltdfini(td); 367 368 /* 369 * Reset any sigio structures pointing to us as a result of 370 * F_SETOWN with our pid. The P_WEXIT flag interlocks with fsetown(). 371 */ 372 funsetownlst(&p->p_sigiolst); 373 374 /* 375 * Close open files and release open-file table. 376 * This may block! 377 */ 378 pdescfree(td); 379 fdescfree(td); 380 381 /* 382 * If this thread tickled GEOM, we need to wait for the giggling to 383 * stop before we return to userland 384 */ 385 if (td->td_pflags & TDP_GEOM) 386 g_waitidle(); 387 388 /* 389 * Remove ourself from our leader's peer list and wake our leader. 390 */ 391 if (p->p_leader->p_peers != NULL) { 392 mtx_lock(&ppeers_lock); 393 if (p->p_leader->p_peers != NULL) { 394 q = p->p_leader; 395 while (q->p_peers != p) 396 q = q->p_peers; 397 q->p_peers = p->p_peers; 398 wakeup(p->p_leader); 399 } 400 mtx_unlock(&ppeers_lock); 401 } 402 403 vmspace_exit(td); 404 (void)acct_process(td); 405 406 #ifdef KTRACE 407 ktrprocexit(td); 408 #endif 409 /* 410 * Release reference to text vnode 411 */ 412 if (p->p_textvp != NULL) { 413 vrele(p->p_textvp); 414 p->p_textvp = NULL; 415 } 416 417 /* 418 * Release our limits structure. 419 */ 420 lim_free(p->p_limit); 421 p->p_limit = NULL; 422 423 tidhash_remove(td); 424 425 /* 426 * Call machine-dependent code to release any 427 * machine-dependent resources other than the address space. 428 * The address space is released by "vmspace_exitfree(p)" in 429 * vm_waitproc(). 430 */ 431 cpu_exit(td); 432 433 WITNESS_WARN(WARN_PANIC, NULL, "process (pid %d) exiting", p->p_pid); 434 435 /* 436 * Remove from allproc. It still sits in the hash. 437 */ 438 sx_xlock(&allproc_lock); 439 LIST_REMOVE(p, p_list); 440 441 #ifdef DDB 442 /* 443 * Used by ddb's 'ps' command to find this process via the 444 * pidhash. 445 */ 446 p->p_list.le_prev = NULL; 447 #endif 448 sx_xunlock(&allproc_lock); 449 450 sx_xlock(&proctree_lock); 451 PROC_LOCK(p); 452 p->p_flag &= ~(P_TRACED | P_PPWAIT | P_PPTRACE); 453 PROC_UNLOCK(p); 454 455 /* 456 * killjobc() might drop and re-acquire proctree_lock to 457 * revoke control tty if exiting process was a session leader. 458 */ 459 killjobc(); 460 461 /* 462 * Reparent all children processes: 463 * - traced ones to the original parent (or init if we are that parent) 464 * - the rest to init 465 */ 466 q = LIST_FIRST(&p->p_children); 467 if (q != NULL) /* only need this if any child is S_ZOMB */ 468 wakeup(q->p_reaper); 469 for (; q != NULL; q = nq) { 470 nq = LIST_NEXT(q, p_sibling); 471 ksi = ksiginfo_alloc(TRUE); 472 PROC_LOCK(q); 473 q->p_sigparent = SIGCHLD; 474 475 if ((q->p_flag & P_TRACED) == 0) { 476 proc_reparent(q, q->p_reaper, true); 477 if (q->p_state == PRS_ZOMBIE) { 478 /* 479 * Inform reaper about the reparented 480 * zombie, since wait(2) has something 481 * new to report. Guarantee queueing 482 * of the SIGCHLD signal, similar to 483 * the _exit() behaviour, by providing 484 * our ksiginfo. Ksi is freed by the 485 * signal delivery. 486 */ 487 if (q->p_ksi == NULL) { 488 ksi1 = NULL; 489 } else { 490 ksiginfo_copy(q->p_ksi, ksi); 491 ksi->ksi_flags |= KSI_INS; 492 ksi1 = ksi; 493 ksi = NULL; 494 } 495 PROC_LOCK(q->p_reaper); 496 pksignal(q->p_reaper, SIGCHLD, ksi1); 497 PROC_UNLOCK(q->p_reaper); 498 } else if (q->p_pdeathsig > 0) { 499 /* 500 * The child asked to received a signal 501 * when we exit. 502 */ 503 kern_psignal(q, q->p_pdeathsig); 504 } 505 } else { 506 /* 507 * Traced processes are killed since their existence 508 * means someone is screwing up. 509 */ 510 t = proc_realparent(q); 511 if (t == p) { 512 proc_reparent(q, q->p_reaper, true); 513 } else { 514 PROC_LOCK(t); 515 proc_reparent(q, t, true); 516 PROC_UNLOCK(t); 517 } 518 /* 519 * Since q was found on our children list, the 520 * proc_reparent() call moved q to the orphan 521 * list due to present P_TRACED flag. Clear 522 * orphan link for q now while q is locked. 523 */ 524 proc_clear_orphan(q); 525 q->p_flag &= ~(P_TRACED | P_STOPPED_TRACE); 526 q->p_flag2 &= ~P2_PTRACE_FSTP; 527 q->p_ptevents = 0; 528 FOREACH_THREAD_IN_PROC(q, tdt) { 529 tdt->td_dbgflags &= ~(TDB_SUSPEND | TDB_XSIG | 530 TDB_FSTP); 531 } 532 kern_psignal(q, SIGKILL); 533 } 534 PROC_UNLOCK(q); 535 if (ksi != NULL) 536 ksiginfo_free(ksi); 537 } 538 539 /* 540 * Also get rid of our orphans. 541 */ 542 while ((q = LIST_FIRST(&p->p_orphans)) != NULL) { 543 PROC_LOCK(q); 544 KASSERT(q->p_oppid == p->p_pid, 545 ("orphan %p of %p has unexpected oppid %d", q, p, 546 q->p_oppid)); 547 q->p_oppid = q->p_reaper->p_pid; 548 549 /* 550 * If we are the real parent of this process 551 * but it has been reparented to a debugger, then 552 * check if it asked for a signal when we exit. 553 */ 554 if (q->p_pdeathsig > 0) 555 kern_psignal(q, q->p_pdeathsig); 556 CTR2(KTR_PTRACE, "exit: pid %d, clearing orphan %d", p->p_pid, 557 q->p_pid); 558 proc_clear_orphan(q); 559 PROC_UNLOCK(q); 560 } 561 562 #ifdef KDTRACE_HOOKS 563 if (SDT_PROBES_ENABLED()) { 564 int reason = CLD_EXITED; 565 if (WCOREDUMP(signo)) 566 reason = CLD_DUMPED; 567 else if (WIFSIGNALED(signo)) 568 reason = CLD_KILLED; 569 SDT_PROBE1(proc, , , exit, reason); 570 } 571 #endif 572 573 /* Save exit status. */ 574 PROC_LOCK(p); 575 p->p_xthread = td; 576 577 if (p->p_sysent->sv_ontdexit != NULL) 578 p->p_sysent->sv_ontdexit(td); 579 580 #ifdef KDTRACE_HOOKS 581 /* 582 * Tell the DTrace fasttrap provider about the exit if it 583 * has declared an interest. 584 */ 585 if (dtrace_fasttrap_exit) 586 dtrace_fasttrap_exit(p); 587 #endif 588 589 /* 590 * Notify interested parties of our demise. 591 */ 592 KNOTE_LOCKED(p->p_klist, NOTE_EXIT); 593 594 /* 595 * If this is a process with a descriptor, we may not need to deliver 596 * a signal to the parent. proctree_lock is held over 597 * procdesc_exit() to serialize concurrent calls to close() and 598 * exit(). 599 */ 600 signal_parent = 0; 601 if (p->p_procdesc == NULL || procdesc_exit(p)) { 602 /* 603 * Notify parent that we're gone. If parent has the 604 * PS_NOCLDWAIT flag set, or if the handler is set to SIG_IGN, 605 * notify process 1 instead (and hope it will handle this 606 * situation). 607 */ 608 PROC_LOCK(p->p_pptr); 609 mtx_lock(&p->p_pptr->p_sigacts->ps_mtx); 610 if (p->p_pptr->p_sigacts->ps_flag & 611 (PS_NOCLDWAIT | PS_CLDSIGIGN)) { 612 struct proc *pp; 613 614 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); 615 pp = p->p_pptr; 616 PROC_UNLOCK(pp); 617 proc_reparent(p, p->p_reaper, true); 618 p->p_sigparent = SIGCHLD; 619 PROC_LOCK(p->p_pptr); 620 621 /* 622 * Notify parent, so in case he was wait(2)ing or 623 * executing waitpid(2) with our pid, he will 624 * continue. 625 */ 626 wakeup(pp); 627 } else 628 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); 629 630 if (p->p_pptr == p->p_reaper || p->p_pptr == initproc) { 631 signal_parent = 1; 632 } else if (p->p_sigparent != 0) { 633 if (p->p_sigparent == SIGCHLD) { 634 signal_parent = 1; 635 } else { /* LINUX thread */ 636 signal_parent = 2; 637 } 638 } 639 } else 640 PROC_LOCK(p->p_pptr); 641 sx_xunlock(&proctree_lock); 642 643 if (signal_parent == 1) { 644 childproc_exited(p); 645 } else if (signal_parent == 2) { 646 kern_psignal(p->p_pptr, p->p_sigparent); 647 } 648 649 /* Tell the prison that we are gone. */ 650 prison_proc_free(p->p_ucred->cr_prison); 651 652 /* 653 * The state PRS_ZOMBIE prevents other proesses from sending 654 * signal to the process, to avoid memory leak, we free memory 655 * for signal queue at the time when the state is set. 656 */ 657 sigqueue_flush(&p->p_sigqueue); 658 sigqueue_flush(&td->td_sigqueue); 659 660 /* 661 * We have to wait until after acquiring all locks before 662 * changing p_state. We need to avoid all possible context 663 * switches (including ones from blocking on a mutex) while 664 * marked as a zombie. We also have to set the zombie state 665 * before we release the parent process' proc lock to avoid 666 * a lost wakeup. So, we first call wakeup, then we grab the 667 * sched lock, update the state, and release the parent process' 668 * proc lock. 669 */ 670 wakeup(p->p_pptr); 671 cv_broadcast(&p->p_pwait); 672 sched_exit(p->p_pptr, td); 673 PROC_SLOCK(p); 674 p->p_state = PRS_ZOMBIE; 675 PROC_UNLOCK(p->p_pptr); 676 677 /* 678 * Save our children's rusage information in our exit rusage. 679 */ 680 PROC_STATLOCK(p); 681 ruadd(&p->p_ru, &p->p_rux, &p->p_stats->p_cru, &p->p_crux); 682 PROC_STATUNLOCK(p); 683 684 /* 685 * Make sure the scheduler takes this thread out of its tables etc. 686 * This will also release this thread's reference to the ucred. 687 * Other thread parts to release include pcb bits and such. 688 */ 689 thread_exit(); 690 } 691 692 #ifndef _SYS_SYSPROTO_H_ 693 struct abort2_args { 694 char *why; 695 int nargs; 696 void **args; 697 }; 698 #endif 699 700 int 701 sys_abort2(struct thread *td, struct abort2_args *uap) 702 { 703 struct proc *p = td->td_proc; 704 struct sbuf *sb; 705 void *uargs[16]; 706 int error, i, sig; 707 708 /* 709 * Do it right now so we can log either proper call of abort2(), or 710 * note, that invalid argument was passed. 512 is big enough to 711 * handle 16 arguments' descriptions with additional comments. 712 */ 713 sb = sbuf_new(NULL, NULL, 512, SBUF_FIXEDLEN); 714 sbuf_clear(sb); 715 sbuf_printf(sb, "%s(pid %d uid %d) aborted: ", 716 p->p_comm, p->p_pid, td->td_ucred->cr_uid); 717 /* 718 * Since we can't return from abort2(), send SIGKILL in cases, where 719 * abort2() was called improperly 720 */ 721 sig = SIGKILL; 722 /* Prevent from DoSes from user-space. */ 723 if (uap->nargs < 0 || uap->nargs > 16) 724 goto out; 725 if (uap->nargs > 0) { 726 if (uap->args == NULL) 727 goto out; 728 error = copyin(uap->args, uargs, uap->nargs * sizeof(void *)); 729 if (error != 0) 730 goto out; 731 } 732 /* 733 * Limit size of 'reason' string to 128. Will fit even when 734 * maximal number of arguments was chosen to be logged. 735 */ 736 if (uap->why != NULL) { 737 error = sbuf_copyin(sb, uap->why, 128); 738 if (error < 0) 739 goto out; 740 } else { 741 sbuf_printf(sb, "(null)"); 742 } 743 if (uap->nargs > 0) { 744 sbuf_printf(sb, "("); 745 for (i = 0;i < uap->nargs; i++) 746 sbuf_printf(sb, "%s%p", i == 0 ? "" : ", ", uargs[i]); 747 sbuf_printf(sb, ")"); 748 } 749 /* 750 * Final stage: arguments were proper, string has been 751 * successfully copied from userspace, and copying pointers 752 * from user-space succeed. 753 */ 754 sig = SIGABRT; 755 out: 756 if (sig == SIGKILL) { 757 sbuf_trim(sb); 758 sbuf_printf(sb, " (Reason text inaccessible)"); 759 } 760 sbuf_cat(sb, "\n"); 761 sbuf_finish(sb); 762 log(LOG_INFO, "%s", sbuf_data(sb)); 763 sbuf_delete(sb); 764 exit1(td, 0, sig); 765 return (0); 766 } 767 768 #ifdef COMPAT_43 769 /* 770 * The dirty work is handled by kern_wait(). 771 */ 772 int 773 owait(struct thread *td, struct owait_args *uap __unused) 774 { 775 int error, status; 776 777 error = kern_wait(td, WAIT_ANY, &status, 0, NULL); 778 if (error == 0) 779 td->td_retval[1] = status; 780 return (error); 781 } 782 #endif /* COMPAT_43 */ 783 784 /* 785 * The dirty work is handled by kern_wait(). 786 */ 787 int 788 sys_wait4(struct thread *td, struct wait4_args *uap) 789 { 790 struct rusage ru, *rup; 791 int error, status; 792 793 if (uap->rusage != NULL) 794 rup = &ru; 795 else 796 rup = NULL; 797 error = kern_wait(td, uap->pid, &status, uap->options, rup); 798 if (uap->status != NULL && error == 0 && td->td_retval[0] != 0) 799 error = copyout(&status, uap->status, sizeof(status)); 800 if (uap->rusage != NULL && error == 0 && td->td_retval[0] != 0) 801 error = copyout(&ru, uap->rusage, sizeof(struct rusage)); 802 return (error); 803 } 804 805 int 806 sys_wait6(struct thread *td, struct wait6_args *uap) 807 { 808 struct __wrusage wru, *wrup; 809 siginfo_t si, *sip; 810 idtype_t idtype; 811 id_t id; 812 int error, status; 813 814 idtype = uap->idtype; 815 id = uap->id; 816 817 if (uap->wrusage != NULL) 818 wrup = &wru; 819 else 820 wrup = NULL; 821 822 if (uap->info != NULL) { 823 sip = &si; 824 bzero(sip, sizeof(*sip)); 825 } else 826 sip = NULL; 827 828 /* 829 * We expect all callers of wait6() to know about WEXITED and 830 * WTRAPPED. 831 */ 832 error = kern_wait6(td, idtype, id, &status, uap->options, wrup, sip); 833 834 if (uap->status != NULL && error == 0 && td->td_retval[0] != 0) 835 error = copyout(&status, uap->status, sizeof(status)); 836 if (uap->wrusage != NULL && error == 0 && td->td_retval[0] != 0) 837 error = copyout(&wru, uap->wrusage, sizeof(wru)); 838 if (uap->info != NULL && error == 0) 839 error = copyout(&si, uap->info, sizeof(si)); 840 return (error); 841 } 842 843 /* 844 * Reap the remains of a zombie process and optionally return status and 845 * rusage. Asserts and will release both the proctree_lock and the process 846 * lock as part of its work. 847 */ 848 void 849 proc_reap(struct thread *td, struct proc *p, int *status, int options) 850 { 851 struct proc *q, *t; 852 853 sx_assert(&proctree_lock, SA_XLOCKED); 854 PROC_LOCK_ASSERT(p, MA_OWNED); 855 KASSERT(p->p_state == PRS_ZOMBIE, ("proc_reap: !PRS_ZOMBIE")); 856 857 mtx_spin_wait_unlocked(&p->p_slock); 858 859 q = td->td_proc; 860 861 if (status) 862 *status = KW_EXITCODE(p->p_xexit, p->p_xsig); 863 if (options & WNOWAIT) { 864 /* 865 * Only poll, returning the status. Caller does not wish to 866 * release the proc struct just yet. 867 */ 868 PROC_UNLOCK(p); 869 sx_xunlock(&proctree_lock); 870 return; 871 } 872 873 PROC_LOCK(q); 874 sigqueue_take(p->p_ksi); 875 PROC_UNLOCK(q); 876 877 /* 878 * If we got the child via a ptrace 'attach', we need to give it back 879 * to the old parent. 880 */ 881 if (p->p_oppid != p->p_pptr->p_pid) { 882 PROC_UNLOCK(p); 883 t = proc_realparent(p); 884 PROC_LOCK(t); 885 PROC_LOCK(p); 886 CTR2(KTR_PTRACE, 887 "wait: traced child %d moved back to parent %d", p->p_pid, 888 t->p_pid); 889 proc_reparent(p, t, false); 890 PROC_UNLOCK(p); 891 pksignal(t, SIGCHLD, p->p_ksi); 892 wakeup(t); 893 cv_broadcast(&p->p_pwait); 894 PROC_UNLOCK(t); 895 sx_xunlock(&proctree_lock); 896 return; 897 } 898 PROC_UNLOCK(p); 899 900 /* 901 * Remove other references to this process to ensure we have an 902 * exclusive reference. 903 */ 904 sx_xlock(PIDHASHLOCK(p->p_pid)); 905 LIST_REMOVE(p, p_hash); 906 sx_xunlock(PIDHASHLOCK(p->p_pid)); 907 LIST_REMOVE(p, p_sibling); 908 reaper_abandon_children(p, true); 909 reaper_clear(p); 910 PROC_LOCK(p); 911 proc_clear_orphan(p); 912 PROC_UNLOCK(p); 913 leavepgrp(p); 914 if (p->p_procdesc != NULL) 915 procdesc_reap(p); 916 sx_xunlock(&proctree_lock); 917 918 proc_id_clear(PROC_ID_PID, p->p_pid); 919 920 PROC_LOCK(p); 921 knlist_detach(p->p_klist); 922 p->p_klist = NULL; 923 PROC_UNLOCK(p); 924 925 /* 926 * Removal from allproc list and process group list paired with 927 * PROC_LOCK which was executed during that time should guarantee 928 * nothing can reach this process anymore. As such further locking 929 * is unnecessary. 930 */ 931 p->p_xexit = p->p_xsig = 0; /* XXX: why? */ 932 933 PROC_LOCK(q); 934 ruadd(&q->p_stats->p_cru, &q->p_crux, &p->p_ru, &p->p_rux); 935 PROC_UNLOCK(q); 936 937 /* 938 * Decrement the count of procs running with this uid. 939 */ 940 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0); 941 942 /* 943 * Destroy resource accounting information associated with the process. 944 */ 945 #ifdef RACCT 946 if (racct_enable) { 947 PROC_LOCK(p); 948 racct_sub(p, RACCT_NPROC, 1); 949 PROC_UNLOCK(p); 950 } 951 #endif 952 racct_proc_exit(p); 953 954 /* 955 * Free credentials, arguments, and sigacts. 956 */ 957 proc_unset_cred(p); 958 pargs_drop(p->p_args); 959 p->p_args = NULL; 960 sigacts_free(p->p_sigacts); 961 p->p_sigacts = NULL; 962 963 /* 964 * Do any thread-system specific cleanups. 965 */ 966 thread_wait(p); 967 968 /* 969 * Give vm and machine-dependent layer a chance to free anything that 970 * cpu_exit couldn't release while still running in process context. 971 */ 972 vm_waitproc(p); 973 #ifdef MAC 974 mac_proc_destroy(p); 975 #endif 976 977 KASSERT(FIRST_THREAD_IN_PROC(p), 978 ("proc_reap: no residual thread!")); 979 uma_zfree(proc_zone, p); 980 atomic_add_int(&nprocs, -1); 981 } 982 983 static int 984 proc_to_reap(struct thread *td, struct proc *p, idtype_t idtype, id_t id, 985 int *status, int options, struct __wrusage *wrusage, siginfo_t *siginfo, 986 int check_only) 987 { 988 struct rusage *rup; 989 990 sx_assert(&proctree_lock, SA_XLOCKED); 991 992 PROC_LOCK(p); 993 994 switch (idtype) { 995 case P_ALL: 996 if (p->p_procdesc == NULL || 997 (p->p_pptr == td->td_proc && 998 (p->p_flag & P_TRACED) != 0)) { 999 break; 1000 } 1001 1002 PROC_UNLOCK(p); 1003 return (0); 1004 case P_PID: 1005 if (p->p_pid != (pid_t)id) { 1006 PROC_UNLOCK(p); 1007 return (0); 1008 } 1009 break; 1010 case P_PGID: 1011 if (p->p_pgid != (pid_t)id) { 1012 PROC_UNLOCK(p); 1013 return (0); 1014 } 1015 break; 1016 case P_SID: 1017 if (p->p_session->s_sid != (pid_t)id) { 1018 PROC_UNLOCK(p); 1019 return (0); 1020 } 1021 break; 1022 case P_UID: 1023 if (p->p_ucred->cr_uid != (uid_t)id) { 1024 PROC_UNLOCK(p); 1025 return (0); 1026 } 1027 break; 1028 case P_GID: 1029 if (p->p_ucred->cr_gid != (gid_t)id) { 1030 PROC_UNLOCK(p); 1031 return (0); 1032 } 1033 break; 1034 case P_JAILID: 1035 if (p->p_ucred->cr_prison->pr_id != (int)id) { 1036 PROC_UNLOCK(p); 1037 return (0); 1038 } 1039 break; 1040 /* 1041 * It seems that the thread structures get zeroed out 1042 * at process exit. This makes it impossible to 1043 * support P_SETID, P_CID or P_CPUID. 1044 */ 1045 default: 1046 PROC_UNLOCK(p); 1047 return (0); 1048 } 1049 1050 if (p_canwait(td, p)) { 1051 PROC_UNLOCK(p); 1052 return (0); 1053 } 1054 1055 if (((options & WEXITED) == 0) && (p->p_state == PRS_ZOMBIE)) { 1056 PROC_UNLOCK(p); 1057 return (0); 1058 } 1059 1060 /* 1061 * This special case handles a kthread spawned by linux_clone 1062 * (see linux_misc.c). The linux_wait4 and linux_waitpid 1063 * functions need to be able to distinguish between waiting 1064 * on a process and waiting on a thread. It is a thread if 1065 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option 1066 * signifies we want to wait for threads and not processes. 1067 */ 1068 if ((p->p_sigparent != SIGCHLD) ^ 1069 ((options & WLINUXCLONE) != 0)) { 1070 PROC_UNLOCK(p); 1071 return (0); 1072 } 1073 1074 if (siginfo != NULL) { 1075 bzero(siginfo, sizeof(*siginfo)); 1076 siginfo->si_errno = 0; 1077 1078 /* 1079 * SUSv4 requires that the si_signo value is always 1080 * SIGCHLD. Obey it despite the rfork(2) interface 1081 * allows to request other signal for child exit 1082 * notification. 1083 */ 1084 siginfo->si_signo = SIGCHLD; 1085 1086 /* 1087 * This is still a rough estimate. We will fix the 1088 * cases TRAPPED, STOPPED, and CONTINUED later. 1089 */ 1090 if (WCOREDUMP(p->p_xsig)) { 1091 siginfo->si_code = CLD_DUMPED; 1092 siginfo->si_status = WTERMSIG(p->p_xsig); 1093 } else if (WIFSIGNALED(p->p_xsig)) { 1094 siginfo->si_code = CLD_KILLED; 1095 siginfo->si_status = WTERMSIG(p->p_xsig); 1096 } else { 1097 siginfo->si_code = CLD_EXITED; 1098 siginfo->si_status = p->p_xexit; 1099 } 1100 1101 siginfo->si_pid = p->p_pid; 1102 siginfo->si_uid = p->p_ucred->cr_uid; 1103 1104 /* 1105 * The si_addr field would be useful additional 1106 * detail, but apparently the PC value may be lost 1107 * when we reach this point. bzero() above sets 1108 * siginfo->si_addr to NULL. 1109 */ 1110 } 1111 1112 /* 1113 * There should be no reason to limit resources usage info to 1114 * exited processes only. A snapshot about any resources used 1115 * by a stopped process may be exactly what is needed. 1116 */ 1117 if (wrusage != NULL) { 1118 rup = &wrusage->wru_self; 1119 *rup = p->p_ru; 1120 PROC_STATLOCK(p); 1121 calcru(p, &rup->ru_utime, &rup->ru_stime); 1122 PROC_STATUNLOCK(p); 1123 1124 rup = &wrusage->wru_children; 1125 *rup = p->p_stats->p_cru; 1126 calccru(p, &rup->ru_utime, &rup->ru_stime); 1127 } 1128 1129 if (p->p_state == PRS_ZOMBIE && !check_only) { 1130 proc_reap(td, p, status, options); 1131 return (-1); 1132 } 1133 return (1); 1134 } 1135 1136 int 1137 kern_wait(struct thread *td, pid_t pid, int *status, int options, 1138 struct rusage *rusage) 1139 { 1140 struct __wrusage wru, *wrup; 1141 idtype_t idtype; 1142 id_t id; 1143 int ret; 1144 1145 /* 1146 * Translate the special pid values into the (idtype, pid) 1147 * pair for kern_wait6. The WAIT_MYPGRP case is handled by 1148 * kern_wait6() on its own. 1149 */ 1150 if (pid == WAIT_ANY) { 1151 idtype = P_ALL; 1152 id = 0; 1153 } else if (pid < 0) { 1154 idtype = P_PGID; 1155 id = (id_t)-pid; 1156 } else { 1157 idtype = P_PID; 1158 id = (id_t)pid; 1159 } 1160 1161 if (rusage != NULL) 1162 wrup = &wru; 1163 else 1164 wrup = NULL; 1165 1166 /* 1167 * For backward compatibility we implicitly add flags WEXITED 1168 * and WTRAPPED here. 1169 */ 1170 options |= WEXITED | WTRAPPED; 1171 ret = kern_wait6(td, idtype, id, status, options, wrup, NULL); 1172 if (rusage != NULL) 1173 *rusage = wru.wru_self; 1174 return (ret); 1175 } 1176 1177 static void 1178 report_alive_proc(struct thread *td, struct proc *p, siginfo_t *siginfo, 1179 int *status, int options, int si_code) 1180 { 1181 bool cont; 1182 1183 PROC_LOCK_ASSERT(p, MA_OWNED); 1184 sx_assert(&proctree_lock, SA_XLOCKED); 1185 MPASS(si_code == CLD_TRAPPED || si_code == CLD_STOPPED || 1186 si_code == CLD_CONTINUED); 1187 1188 cont = si_code == CLD_CONTINUED; 1189 if ((options & WNOWAIT) == 0) { 1190 if (cont) 1191 p->p_flag &= ~P_CONTINUED; 1192 else 1193 p->p_flag |= P_WAITED; 1194 PROC_LOCK(td->td_proc); 1195 sigqueue_take(p->p_ksi); 1196 PROC_UNLOCK(td->td_proc); 1197 } 1198 sx_xunlock(&proctree_lock); 1199 if (siginfo != NULL) { 1200 siginfo->si_code = si_code; 1201 siginfo->si_status = cont ? SIGCONT : p->p_xsig; 1202 } 1203 if (status != NULL) 1204 *status = cont ? SIGCONT : W_STOPCODE(p->p_xsig); 1205 PROC_UNLOCK(p); 1206 td->td_retval[0] = p->p_pid; 1207 } 1208 1209 int 1210 kern_wait6(struct thread *td, idtype_t idtype, id_t id, int *status, 1211 int options, struct __wrusage *wrusage, siginfo_t *siginfo) 1212 { 1213 struct proc *p, *q; 1214 pid_t pid; 1215 int error, nfound, ret; 1216 bool report; 1217 1218 AUDIT_ARG_VALUE((int)idtype); /* XXX - This is likely wrong! */ 1219 AUDIT_ARG_PID((pid_t)id); /* XXX - This may be wrong! */ 1220 AUDIT_ARG_VALUE(options); 1221 1222 q = td->td_proc; 1223 1224 if ((pid_t)id == WAIT_MYPGRP && (idtype == P_PID || idtype == P_PGID)) { 1225 PROC_LOCK(q); 1226 id = (id_t)q->p_pgid; 1227 PROC_UNLOCK(q); 1228 idtype = P_PGID; 1229 } 1230 1231 /* If we don't know the option, just return. */ 1232 if ((options & ~(WUNTRACED | WNOHANG | WCONTINUED | WNOWAIT | 1233 WEXITED | WTRAPPED | WLINUXCLONE)) != 0) 1234 return (EINVAL); 1235 if ((options & (WEXITED | WUNTRACED | WCONTINUED | WTRAPPED)) == 0) { 1236 /* 1237 * We will be unable to find any matching processes, 1238 * because there are no known events to look for. 1239 * Prefer to return error instead of blocking 1240 * indefinitely. 1241 */ 1242 return (EINVAL); 1243 } 1244 1245 loop: 1246 if (q->p_flag & P_STATCHILD) { 1247 PROC_LOCK(q); 1248 q->p_flag &= ~P_STATCHILD; 1249 PROC_UNLOCK(q); 1250 } 1251 sx_xlock(&proctree_lock); 1252 loop_locked: 1253 nfound = 0; 1254 LIST_FOREACH(p, &q->p_children, p_sibling) { 1255 pid = p->p_pid; 1256 ret = proc_to_reap(td, p, idtype, id, status, options, 1257 wrusage, siginfo, 0); 1258 if (ret == 0) 1259 continue; 1260 else if (ret != 1) { 1261 td->td_retval[0] = pid; 1262 return (0); 1263 } 1264 1265 nfound++; 1266 PROC_LOCK_ASSERT(p, MA_OWNED); 1267 1268 if ((options & WTRAPPED) != 0 && 1269 (p->p_flag & P_TRACED) != 0) { 1270 PROC_SLOCK(p); 1271 report = 1272 ((p->p_flag & (P_STOPPED_TRACE | P_STOPPED_SIG)) && 1273 p->p_suspcount == p->p_numthreads && 1274 (p->p_flag & P_WAITED) == 0); 1275 PROC_SUNLOCK(p); 1276 if (report) { 1277 CTR4(KTR_PTRACE, 1278 "wait: returning trapped pid %d status %#x " 1279 "(xstat %d) xthread %d", 1280 p->p_pid, W_STOPCODE(p->p_xsig), p->p_xsig, 1281 p->p_xthread != NULL ? 1282 p->p_xthread->td_tid : -1); 1283 report_alive_proc(td, p, siginfo, status, 1284 options, CLD_TRAPPED); 1285 return (0); 1286 } 1287 } 1288 if ((options & WUNTRACED) != 0 && 1289 (p->p_flag & P_STOPPED_SIG) != 0) { 1290 PROC_SLOCK(p); 1291 report = (p->p_suspcount == p->p_numthreads && 1292 ((p->p_flag & P_WAITED) == 0)); 1293 PROC_SUNLOCK(p); 1294 if (report) { 1295 report_alive_proc(td, p, siginfo, status, 1296 options, CLD_STOPPED); 1297 return (0); 1298 } 1299 } 1300 if ((options & WCONTINUED) != 0 && 1301 (p->p_flag & P_CONTINUED) != 0) { 1302 report_alive_proc(td, p, siginfo, status, options, 1303 CLD_CONTINUED); 1304 return (0); 1305 } 1306 PROC_UNLOCK(p); 1307 } 1308 1309 /* 1310 * Look in the orphans list too, to allow the parent to 1311 * collect it's child exit status even if child is being 1312 * debugged. 1313 * 1314 * Debugger detaches from the parent upon successful 1315 * switch-over from parent to child. At this point due to 1316 * re-parenting the parent loses the child to debugger and a 1317 * wait4(2) call would report that it has no children to wait 1318 * for. By maintaining a list of orphans we allow the parent 1319 * to successfully wait until the child becomes a zombie. 1320 */ 1321 if (nfound == 0) { 1322 LIST_FOREACH(p, &q->p_orphans, p_orphan) { 1323 ret = proc_to_reap(td, p, idtype, id, NULL, options, 1324 NULL, NULL, 1); 1325 if (ret != 0) { 1326 KASSERT(ret != -1, ("reaped an orphan (pid %d)", 1327 (int)td->td_retval[0])); 1328 PROC_UNLOCK(p); 1329 nfound++; 1330 break; 1331 } 1332 } 1333 } 1334 if (nfound == 0) { 1335 sx_xunlock(&proctree_lock); 1336 return (ECHILD); 1337 } 1338 if (options & WNOHANG) { 1339 sx_xunlock(&proctree_lock); 1340 td->td_retval[0] = 0; 1341 return (0); 1342 } 1343 PROC_LOCK(q); 1344 if (q->p_flag & P_STATCHILD) { 1345 q->p_flag &= ~P_STATCHILD; 1346 PROC_UNLOCK(q); 1347 goto loop_locked; 1348 } 1349 sx_xunlock(&proctree_lock); 1350 error = msleep(q, &q->p_mtx, PWAIT | PCATCH | PDROP, "wait", 0); 1351 if (error) 1352 return (error); 1353 goto loop; 1354 } 1355 1356 void 1357 proc_add_orphan(struct proc *child, struct proc *parent) 1358 { 1359 1360 sx_assert(&proctree_lock, SX_XLOCKED); 1361 KASSERT((child->p_flag & P_TRACED) != 0, 1362 ("proc_add_orphan: not traced")); 1363 1364 if (LIST_EMPTY(&parent->p_orphans)) { 1365 child->p_treeflag |= P_TREE_FIRST_ORPHAN; 1366 LIST_INSERT_HEAD(&parent->p_orphans, child, p_orphan); 1367 } else { 1368 LIST_INSERT_AFTER(LIST_FIRST(&parent->p_orphans), 1369 child, p_orphan); 1370 } 1371 child->p_treeflag |= P_TREE_ORPHANED; 1372 } 1373 1374 /* 1375 * Make process 'parent' the new parent of process 'child'. 1376 * Must be called with an exclusive hold of proctree lock. 1377 */ 1378 void 1379 proc_reparent(struct proc *child, struct proc *parent, bool set_oppid) 1380 { 1381 1382 sx_assert(&proctree_lock, SX_XLOCKED); 1383 PROC_LOCK_ASSERT(child, MA_OWNED); 1384 if (child->p_pptr == parent) 1385 return; 1386 1387 PROC_LOCK(child->p_pptr); 1388 sigqueue_take(child->p_ksi); 1389 PROC_UNLOCK(child->p_pptr); 1390 LIST_REMOVE(child, p_sibling); 1391 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling); 1392 1393 proc_clear_orphan(child); 1394 if ((child->p_flag & P_TRACED) != 0) { 1395 proc_add_orphan(child, child->p_pptr); 1396 } 1397 1398 child->p_pptr = parent; 1399 if (set_oppid) 1400 child->p_oppid = parent->p_pid; 1401 } 1402