1 | /* |
2 | * Copyright (c) 2000-2007, 2015 Apple Inc. All rights reserved. |
3 | * |
4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
5 | * |
6 | * This file contains Original Code and/or Modifications of Original Code |
7 | * as defined in and that are subject to the Apple Public Source License |
8 | * Version 2.0 (the 'License'). You may not use this file except in |
9 | * compliance with the License. The rights granted to you under the License |
10 | * may not be used to create, or enable the creation or redistribution of, |
11 | * unlawful or unlicensed copies of an Apple operating system, or to |
12 | * circumvent, violate, or enable the circumvention or violation of, any |
13 | * terms of an Apple operating system software license agreement. |
14 | * |
15 | * Please obtain a copy of the License at |
16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
17 | * |
18 | * The Original Code and all software distributed under the License are |
19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
23 | * Please see the License for the specific language governing rights and |
24 | * limitations under the License. |
25 | * |
26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
27 | */ |
28 | /* Copyright (c) 1995, 1997 Apple Computer, Inc. All Rights Reserved */ |
29 | /* |
30 | * Copyright (c) 1982, 1986, 1989, 1991, 1993 |
31 | * The Regents of the University of California. All rights reserved. |
32 | * (c) UNIX System Laboratories, Inc. |
33 | * All or some portions of this file are derived from material licensed |
34 | * to the University of California by American Telephone and Telegraph |
35 | * Co. or Unix System Laboratories, Inc. and are reproduced herein with |
36 | * the permission of UNIX System Laboratories, Inc. |
37 | * |
38 | * Redistribution and use in source and binary forms, with or without |
39 | * modification, are permitted provided that the following conditions |
40 | * are met: |
41 | * 1. Redistributions of source code must retain the above copyright |
42 | * notice, this list of conditions and the following disclaimer. |
43 | * 2. Redistributions in binary form must reproduce the above copyright |
44 | * notice, this list of conditions and the following disclaimer in the |
45 | * documentation and/or other materials provided with the distribution. |
46 | * 3. All advertising materials mentioning features or use of this software |
47 | * must display the following acknowledgement: |
48 | * This product includes software developed by the University of |
49 | * California, Berkeley and its contributors. |
50 | * 4. Neither the name of the University nor the names of its contributors |
51 | * may be used to endorse or promote products derived from this software |
52 | * without specific prior written permission. |
53 | * |
54 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
55 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
56 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
57 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
58 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
59 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
60 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
61 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
62 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
63 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
64 | * SUCH DAMAGE. |
65 | * |
66 | * @(#)kern_fork.c 8.8 (Berkeley) 2/14/95 |
67 | */ |
68 | /* |
69 | * NOTICE: This file was modified by McAfee Research in 2004 to introduce |
70 | * support for mandatory and extensible security protections. This notice |
71 | * is included in support of clause 2.2 (b) of the Apple Public License, |
72 | * Version 2.0. |
73 | */ |
74 | /* |
75 | * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce |
76 | * support for mandatory and extensible security protections. This notice |
77 | * is included in support of clause 2.2 (b) of the Apple Public License, |
78 | * Version 2.0. |
79 | */ |
80 | |
81 | #include <kern/assert.h> |
82 | #include <sys/param.h> |
83 | #include <sys/systm.h> |
84 | #include <sys/filedesc.h> |
85 | #include <sys/kernel.h> |
86 | #include <sys/malloc.h> |
87 | #include <sys/proc_internal.h> |
88 | #include <sys/kauth.h> |
89 | #include <sys/user.h> |
90 | #include <sys/reason.h> |
91 | #include <sys/resourcevar.h> |
92 | #include <sys/vnode_internal.h> |
93 | #include <sys/file_internal.h> |
94 | #include <sys/acct.h> |
95 | #include <sys/codesign.h> |
96 | #include <sys/sysproto.h> |
97 | #if CONFIG_PERSONAS |
98 | #include <sys/persona.h> |
99 | #endif |
100 | #include <sys/doc_tombstone.h> |
101 | #if CONFIG_DTRACE |
102 | /* Do not include dtrace.h, it redefines kmem_[alloc/free] */ |
103 | extern void (*dtrace_proc_waitfor_exec_ptr)(proc_t); |
104 | extern void dtrace_proc_fork(proc_t, proc_t, int); |
105 | |
106 | /* |
107 | * Since dtrace_proc_waitfor_exec_ptr can be added/removed in dtrace_subr.c, |
108 | * we will store its value before actually calling it. |
109 | */ |
110 | static void (*dtrace_proc_waitfor_hook)(proc_t) = NULL; |
111 | |
112 | #include <sys/dtrace_ptss.h> |
113 | #endif |
114 | |
115 | #include <security/audit/audit.h> |
116 | |
117 | #include <mach/mach_types.h> |
118 | #include <kern/coalition.h> |
119 | #include <kern/kern_types.h> |
120 | #include <kern/kalloc.h> |
121 | #include <kern/mach_param.h> |
122 | #include <kern/task.h> |
123 | #include <kern/thread.h> |
124 | #include <kern/thread_call.h> |
125 | #include <kern/zalloc.h> |
126 | |
127 | #include <os/log.h> |
128 | |
129 | #include <os/log.h> |
130 | |
131 | #if CONFIG_MACF |
132 | #include <security/mac_framework.h> |
133 | #include <security/mac_mach_internal.h> |
134 | #endif |
135 | |
136 | #include <vm/vm_map.h> |
137 | #include <vm/vm_protos.h> |
138 | #include <vm/vm_shared_region.h> |
139 | |
140 | #include <sys/shm_internal.h> /* for shmfork() */ |
141 | #include <mach/task.h> /* for thread_create() */ |
142 | #include <mach/thread_act.h> /* for thread_resume() */ |
143 | |
144 | #include <sys/sdt.h> |
145 | |
146 | #if CONFIG_MEMORYSTATUS |
147 | #include <sys/kern_memorystatus.h> |
148 | #endif |
149 | |
150 | /* XXX routines which should have Mach prototypes, but don't */ |
151 | void thread_set_parent(thread_t parent, int pid); |
152 | extern void act_thread_catt(void *ctx); |
153 | void thread_set_child(thread_t child, int pid); |
154 | void *act_thread_csave(void); |
155 | extern boolean_t task_is_exec_copy(task_t); |
156 | |
157 | |
158 | thread_t cloneproc(task_t, coalition_t *, proc_t, int, int); |
159 | proc_t forkproc(proc_t); |
160 | void forkproc_free(proc_t); |
161 | thread_t fork_create_child(task_t parent_task, |
162 | coalition_t *parent_coalitions, |
163 | proc_t child, |
164 | int inherit_memory, |
165 | int is_64bit_addr, |
166 | int is_64bit_data, |
167 | int in_exec); |
168 | void proc_vfork_begin(proc_t parent_proc); |
169 | void proc_vfork_end(proc_t parent_proc); |
170 | |
171 | #define DOFORK 0x1 /* fork() system call */ |
172 | #define DOVFORK 0x2 /* vfork() system call */ |
173 | |
174 | /* |
175 | * proc_vfork_begin |
176 | * |
177 | * Description: start a vfork on a process |
178 | * |
179 | * Parameters: parent_proc process (re)entering vfork state |
180 | * |
181 | * Returns: (void) |
182 | * |
183 | * Notes: Although this function increments a count, a count in |
184 | * excess of 1 is not currently supported. According to the |
185 | * POSIX standard, calling anything other than execve() or |
186 | * _exit() following a vfork(), including calling vfork() |
187 | * itself again, will result in undefined behaviour |
188 | */ |
189 | void |
190 | proc_vfork_begin(proc_t parent_proc) |
191 | { |
192 | proc_lock(parent_proc); |
193 | parent_proc->p_lflag |= P_LVFORK; |
194 | parent_proc->p_vforkcnt++; |
195 | proc_unlock(parent_proc); |
196 | } |
197 | |
198 | /* |
199 | * proc_vfork_end |
200 | * |
201 | * Description: stop a vfork on a process |
202 | * |
203 | * Parameters: parent_proc process leaving vfork state |
204 | * |
205 | * Returns: (void) |
206 | * |
207 | * Notes: Decrements the count; currently, reentrancy of vfork() |
208 | * is unsupported on the current process |
209 | */ |
210 | void |
211 | proc_vfork_end(proc_t parent_proc) |
212 | { |
213 | proc_lock(parent_proc); |
214 | parent_proc->p_vforkcnt--; |
215 | if (parent_proc->p_vforkcnt < 0) |
216 | panic("vfork cnt is -ve" ); |
217 | if (parent_proc->p_vforkcnt == 0) |
218 | parent_proc->p_lflag &= ~P_LVFORK; |
219 | proc_unlock(parent_proc); |
220 | } |
221 | |
222 | |
223 | /* |
224 | * vfork |
225 | * |
226 | * Description: vfork system call |
227 | * |
228 | * Parameters: void [no arguments] |
229 | * |
230 | * Retval: 0 (to child process) |
231 | * !0 pid of child (to parent process) |
232 | * -1 error (see "Returns:") |
233 | * |
234 | * Returns: EAGAIN Administrative limit reached |
235 | * EINVAL vfork() called during vfork() |
236 | * ENOMEM Failed to allocate new process |
237 | * |
238 | * Note: After a successful call to this function, the parent process |
239 | * has its task, thread, and uthread lent to the child process, |
240 | * and control is returned to the caller; if this function is |
241 | * invoked as a system call, the return is to user space, and |
242 | * is effectively running on the child process. |
243 | * |
244 | * Subsequent calls that operate on process state are permitted, |
245 | * though discouraged, and will operate on the child process; any |
246 | * operations on the task, thread, or uthread will result in |
247 | * changes in the parent state, and, if inheritable, the child |
248 | * state, when a task, thread, and uthread are realized for the |
249 | * child process at execve() time, will also be effected. Given |
250 | * this, it's recemmended that people use the posix_spawn() call |
251 | * instead. |
252 | * |
253 | * BLOCK DIAGRAM OF VFORK |
254 | * |
255 | * Before: |
256 | * |
257 | * ,----------------. ,-------------. |
258 | * | | task | | |
259 | * | parent_thread | ------> | parent_task | |
260 | * | | <.list. | | |
261 | * `----------------' `-------------' |
262 | * uthread | ^ bsd_info | ^ |
263 | * v | vc_thread v | task |
264 | * ,----------------. ,-------------. |
265 | * | | | | |
266 | * | parent_uthread | <.list. | parent_proc | <-- current_proc() |
267 | * | | | | |
268 | * `----------------' `-------------' |
269 | * uu_proc | |
270 | * v |
271 | * NULL |
272 | * |
273 | * After: |
274 | * |
275 | * ,----------------. ,-------------. |
276 | * | | task | | |
277 | * ,----> | parent_thread | ------> | parent_task | |
278 | * | | | <.list. | | |
279 | * | `----------------' `-------------' |
280 | * | uthread | ^ bsd_info | ^ |
281 | * | v | vc_thread v | task |
282 | * | ,----------------. ,-------------. |
283 | * | | | | | |
284 | * | | parent_uthread | <.list. | parent_proc | |
285 | * | | | | | |
286 | * | `----------------' `-------------' |
287 | * | uu_proc | . list |
288 | * | v v |
289 | * | ,----------------. |
290 | * `----- | | |
291 | * p_vforkact | child_proc | <-- current_proc() |
292 | * | | |
293 | * `----------------' |
294 | */ |
295 | int |
296 | vfork(proc_t parent_proc, __unused struct vfork_args *uap, int32_t *retval) |
297 | { |
298 | thread_t child_thread; |
299 | int err; |
300 | |
301 | if ((err = fork1(parent_proc, &child_thread, PROC_CREATE_VFORK, NULL)) != 0) { |
302 | retval[1] = 0; |
303 | } else { |
304 | uthread_t ut = get_bsdthread_info(current_thread()); |
305 | proc_t child_proc = ut->uu_proc; |
306 | |
307 | retval[0] = child_proc->p_pid; |
308 | retval[1] = 1; /* flag child return for user space */ |
309 | |
310 | /* |
311 | * Drop the signal lock on the child which was taken on our |
312 | * behalf by forkproc()/cloneproc() to prevent signals being |
313 | * received by the child in a partially constructed state. |
314 | */ |
315 | proc_signalend(child_proc, 0); |
316 | proc_transend(child_proc, 0); |
317 | |
318 | proc_knote(parent_proc, NOTE_FORK | child_proc->p_pid); |
319 | DTRACE_PROC1(create, proc_t, child_proc); |
320 | ut->uu_flag &= ~UT_VFORKING; |
321 | } |
322 | |
323 | return (err); |
324 | } |
325 | |
326 | |
327 | /* |
328 | * fork1 |
329 | * |
330 | * Description: common code used by all new process creation other than the |
331 | * bootstrap of the initial process on the system |
332 | * |
333 | * Parameters: parent_proc parent process of the process being |
334 | * child_threadp pointer to location to receive the |
335 | * Mach thread_t of the child process |
336 | * created |
337 | * kind kind of creation being requested |
338 | * coalitions if spawn, the set of coalitions the |
339 | * child process should join, or NULL to |
340 | * inherit the parent's. On non-spawns, |
341 | * this param is ignored and the child |
342 | * always inherits the parent's |
343 | * coalitions. |
344 | * |
345 | * Notes: Permissable values for 'kind': |
346 | * |
347 | * PROC_CREATE_FORK Create a complete process which will |
348 | * return actively running in both the |
349 | * parent and the child; the child copies |
350 | * the parent address space. |
351 | * PROC_CREATE_SPAWN Create a complete process which will |
352 | * return actively running in the parent |
353 | * only after returning actively running |
354 | * in the child; the child address space |
355 | * is newly created by an image activator, |
356 | * after which the child is run. |
357 | * PROC_CREATE_VFORK Creates a partial process which will |
358 | * borrow the parent task, thread, and |
359 | * uthread to return running in the child; |
360 | * the child address space and other parts |
361 | * are lazily created at execve() time, or |
362 | * the child is terminated, and the parent |
363 | * does not actively run until that |
364 | * happens. |
365 | * |
366 | * At first it may seem strange that we return the child thread |
367 | * address rather than process structure, since the process is |
368 | * the only part guaranteed to be "new"; however, since we do |
369 | * not actualy adjust other references between Mach and BSD (see |
370 | * the block diagram above the implementation of vfork()), this |
371 | * is the only method which guarantees us the ability to get |
372 | * back to the other information. |
373 | */ |
374 | int |
375 | fork1(proc_t parent_proc, thread_t *child_threadp, int kind, coalition_t *coalitions) |
376 | { |
377 | thread_t parent_thread = (thread_t)current_thread(); |
378 | uthread_t parent_uthread = (uthread_t)get_bsdthread_info(parent_thread); |
379 | proc_t child_proc = NULL; /* set in switch, but compiler... */ |
380 | thread_t child_thread = NULL; |
381 | uid_t uid; |
382 | int count; |
383 | int err = 0; |
384 | int spawn = 0; |
385 | |
386 | /* |
387 | * Although process entries are dynamically created, we still keep |
388 | * a global limit on the maximum number we will create. Don't allow |
389 | * a nonprivileged user to use the last process; don't let root |
390 | * exceed the limit. The variable nprocs is the current number of |
391 | * processes, maxproc is the limit. |
392 | */ |
393 | uid = kauth_getruid(); |
394 | proc_list_lock(); |
395 | if ((nprocs >= maxproc - 1 && uid != 0) || nprocs >= maxproc) { |
396 | #if (DEVELOPMENT || DEBUG) && CONFIG_EMBEDDED |
397 | /* |
398 | * On the development kernel, panic so that the fact that we hit |
399 | * the process limit is obvious, as this may very well wedge the |
400 | * system. |
401 | */ |
402 | panic("The process table is full; parent pid=%d" , parent_proc->p_pid); |
403 | #endif |
404 | proc_list_unlock(); |
405 | tablefull("proc" ); |
406 | return (EAGAIN); |
407 | } |
408 | proc_list_unlock(); |
409 | |
410 | /* |
411 | * Increment the count of procs running with this uid. Don't allow |
412 | * a nonprivileged user to exceed their current limit, which is |
413 | * always less than what an rlim_t can hold. |
414 | * (locking protection is provided by list lock held in chgproccnt) |
415 | */ |
416 | count = chgproccnt(uid, 1); |
417 | if (uid != 0 && |
418 | (rlim_t)count > parent_proc->p_rlimit[RLIMIT_NPROC].rlim_cur) { |
419 | #if (DEVELOPMENT || DEBUG) && CONFIG_EMBEDDED |
420 | /* |
421 | * On the development kernel, panic so that the fact that we hit |
422 | * the per user process limit is obvious. This may be less dire |
423 | * than hitting the global process limit, but we cannot rely on |
424 | * that. |
425 | */ |
426 | panic("The per-user process limit has been hit; parent pid=%d, uid=%d" , parent_proc->p_pid, uid); |
427 | #endif |
428 | err = EAGAIN; |
429 | goto bad; |
430 | } |
431 | |
432 | #if CONFIG_MACF |
433 | /* |
434 | * Determine if MAC policies applied to the process will allow |
435 | * it to fork. This is an advisory-only check. |
436 | */ |
437 | err = mac_proc_check_fork(parent_proc); |
438 | if (err != 0) { |
439 | goto bad; |
440 | } |
441 | #endif |
442 | |
443 | switch(kind) { |
444 | case PROC_CREATE_VFORK: |
445 | /* |
446 | * Prevent a vfork while we are in vfork(); we should |
447 | * also likely preventing a fork here as well, and this |
448 | * check should then be outside the switch statement, |
449 | * since the proc struct contents will copy from the |
450 | * child and the tash/thread/uthread from the parent in |
451 | * that case. We do not support vfork() in vfork() |
452 | * because we don't have to; the same non-requirement |
453 | * is true of both fork() and posix_spawn() and any |
454 | * call other than execve() amd _exit(), but we've |
455 | * been historically lenient, so we continue to be so |
456 | * (for now). |
457 | * |
458 | * <rdar://6640521> Probably a source of random panics |
459 | */ |
460 | if (parent_uthread->uu_flag & UT_VFORK) { |
461 | printf("fork1 called within vfork by %s\n" , parent_proc->p_comm); |
462 | err = EINVAL; |
463 | goto bad; |
464 | } |
465 | |
466 | /* |
467 | * Flag us in progress; if we chose to support vfork() in |
468 | * vfork(), we would chain our parent at this point (in |
469 | * effect, a stack push). We don't, since we actually want |
470 | * to disallow everything not specified in the standard |
471 | */ |
472 | proc_vfork_begin(parent_proc); |
473 | |
474 | /* The newly created process comes with signal lock held */ |
475 | if ((child_proc = forkproc(parent_proc)) == NULL) { |
476 | /* Failed to allocate new process */ |
477 | proc_vfork_end(parent_proc); |
478 | err = ENOMEM; |
479 | goto bad; |
480 | } |
481 | |
482 | // XXX BEGIN: wants to move to be common code (and safe) |
483 | #if CONFIG_MACF |
484 | /* |
485 | * allow policies to associate the credential/label that |
486 | * we referenced from the parent ... with the child |
487 | * JMM - this really isn't safe, as we can drop that |
488 | * association without informing the policy in other |
489 | * situations (keep long enough to get policies changed) |
490 | */ |
491 | mac_cred_label_associate_fork(child_proc->p_ucred, child_proc); |
492 | #endif |
493 | |
494 | /* |
495 | * Propogate change of PID - may get new cred if auditing. |
496 | * |
497 | * NOTE: This has no effect in the vfork case, since |
498 | * child_proc->task != current_task(), but we duplicate it |
499 | * because this is probably, ultimately, wrong, since we |
500 | * will be running in the "child" which is the parent task |
501 | * with the wrong token until we get to the execve() or |
502 | * _exit() call; a lot of "undefined" can happen before |
503 | * that. |
504 | * |
505 | * <rdar://6640530> disallow everything but exeve()/_exit()? |
506 | */ |
507 | set_security_token(child_proc); |
508 | |
509 | AUDIT_ARG(pid, child_proc->p_pid); |
510 | |
511 | // XXX END: wants to move to be common code (and safe) |
512 | |
513 | /* |
514 | * BORROW PARENT TASK, THREAD, UTHREAD FOR CHILD |
515 | * |
516 | * Note: this is where we would "push" state instead of setting |
517 | * it for nested vfork() support (see proc_vfork_end() for |
518 | * description if issues here). |
519 | */ |
520 | child_proc->task = parent_proc->task; |
521 | |
522 | child_proc->p_lflag |= P_LINVFORK; |
523 | child_proc->p_vforkact = parent_thread; |
524 | child_proc->p_stat = SRUN; |
525 | |
526 | /* |
527 | * Until UT_VFORKING is cleared at the end of the vfork |
528 | * syscall, the process identity of this thread is slightly |
529 | * murky. |
530 | * |
531 | * As long as UT_VFORK and it's associated field (uu_proc) |
532 | * is set, current_proc() will always return the child process. |
533 | * |
534 | * However dtrace_proc_selfpid() returns the parent pid to |
535 | * ensure that e.g. the proc:::create probe actions accrue |
536 | * to the parent. (Otherwise the child magically seems to |
537 | * have created itself!) |
538 | */ |
539 | parent_uthread->uu_flag |= UT_VFORK | UT_VFORKING; |
540 | parent_uthread->uu_proc = child_proc; |
541 | parent_uthread->uu_userstate = (void *)act_thread_csave(); |
542 | parent_uthread->uu_vforkmask = parent_uthread->uu_sigmask; |
543 | |
544 | /* temporarily drop thread-set-id state */ |
545 | if (parent_uthread->uu_flag & UT_SETUID) { |
546 | parent_uthread->uu_flag |= UT_WASSETUID; |
547 | parent_uthread->uu_flag &= ~UT_SETUID; |
548 | } |
549 | |
550 | /* blow thread state information */ |
551 | /* XXX is this actually necessary, given syscall return? */ |
552 | thread_set_child(parent_thread, child_proc->p_pid); |
553 | |
554 | child_proc->p_acflag = AFORK; /* forked but not exec'ed */ |
555 | |
556 | /* |
557 | * Preserve synchronization semantics of vfork. If |
558 | * waiting for child to exec or exit, set P_PPWAIT |
559 | * on child, and sleep on our proc (in case of exit). |
560 | */ |
561 | child_proc->p_lflag |= P_LPPWAIT; |
562 | pinsertchild(parent_proc, child_proc); /* set visible */ |
563 | |
564 | break; |
565 | |
566 | case PROC_CREATE_SPAWN: |
567 | /* |
568 | * A spawned process differs from a forked process in that |
569 | * the spawned process does not carry around the parents |
570 | * baggage with regard to address space copying, dtrace, |
571 | * and so on. |
572 | */ |
573 | spawn = 1; |
574 | |
575 | /* FALLSTHROUGH */ |
576 | |
577 | case PROC_CREATE_FORK: |
578 | /* |
579 | * When we clone the parent process, we are going to inherit |
580 | * its task attributes and memory, since when we fork, we |
581 | * will, in effect, create a duplicate of it, with only minor |
582 | * differences. Contrarily, spawned processes do not inherit. |
583 | */ |
584 | if ((child_thread = cloneproc(parent_proc->task, |
585 | spawn ? coalitions : NULL, |
586 | parent_proc, |
587 | spawn ? FALSE : TRUE, |
588 | FALSE)) == NULL) { |
589 | /* Failed to create thread */ |
590 | err = EAGAIN; |
591 | goto bad; |
592 | } |
593 | |
594 | /* copy current thread state into the child thread (only for fork) */ |
595 | if (!spawn) { |
596 | thread_dup(child_thread); |
597 | } |
598 | |
599 | /* child_proc = child_thread->task->proc; */ |
600 | child_proc = (proc_t)(get_bsdtask_info(get_threadtask(child_thread))); |
601 | |
602 | // XXX BEGIN: wants to move to be common code (and safe) |
603 | #if CONFIG_MACF |
604 | /* |
605 | * allow policies to associate the credential/label that |
606 | * we referenced from the parent ... with the child |
607 | * JMM - this really isn't safe, as we can drop that |
608 | * association without informing the policy in other |
609 | * situations (keep long enough to get policies changed) |
610 | */ |
611 | mac_cred_label_associate_fork(child_proc->p_ucred, child_proc); |
612 | #endif |
613 | |
614 | /* |
615 | * Propogate change of PID - may get new cred if auditing. |
616 | * |
617 | * NOTE: This has no effect in the vfork case, since |
618 | * child_proc->task != current_task(), but we duplicate it |
619 | * because this is probably, ultimately, wrong, since we |
620 | * will be running in the "child" which is the parent task |
621 | * with the wrong token until we get to the execve() or |
622 | * _exit() call; a lot of "undefined" can happen before |
623 | * that. |
624 | * |
625 | * <rdar://6640530> disallow everything but exeve()/_exit()? |
626 | */ |
627 | set_security_token(child_proc); |
628 | |
629 | AUDIT_ARG(pid, child_proc->p_pid); |
630 | |
631 | // XXX END: wants to move to be common code (and safe) |
632 | |
633 | /* |
634 | * Blow thread state information; this is what gives the child |
635 | * process its "return" value from a fork() call. |
636 | * |
637 | * Note: this should probably move to fork() proper, since it |
638 | * is not relevent to spawn, and the value won't matter |
639 | * until we resume the child there. If you are in here |
640 | * refactoring code, consider doing this at the same time. |
641 | */ |
642 | thread_set_child(child_thread, child_proc->p_pid); |
643 | |
644 | child_proc->p_acflag = AFORK; /* forked but not exec'ed */ |
645 | |
646 | #if CONFIG_DTRACE |
647 | dtrace_proc_fork(parent_proc, child_proc, spawn); |
648 | #endif /* CONFIG_DTRACE */ |
649 | if (!spawn) { |
650 | /* |
651 | * Of note, we need to initialize the bank context behind |
652 | * the protection of the proc_trans lock to prevent a race with exit. |
653 | */ |
654 | task_bank_init(get_threadtask(child_thread)); |
655 | } |
656 | |
657 | break; |
658 | |
659 | default: |
660 | panic("fork1 called with unknown kind %d" , kind); |
661 | break; |
662 | } |
663 | |
664 | |
665 | /* return the thread pointer to the caller */ |
666 | *child_threadp = child_thread; |
667 | |
668 | bad: |
669 | /* |
670 | * In the error case, we return a 0 value for the returned pid (but |
671 | * it is ignored in the trampoline due to the error return); this |
672 | * is probably not necessary. |
673 | */ |
674 | if (err) { |
675 | (void)chgproccnt(uid, -1); |
676 | } |
677 | |
678 | return (err); |
679 | } |
680 | |
681 | |
682 | /* |
683 | * vfork_return |
684 | * |
685 | * Description: "Return" to parent vfork thread() following execve/_exit; |
686 | * this is done by reassociating the parent process structure |
687 | * with the task, thread, and uthread. |
688 | * |
689 | * Refer to the ASCII art above vfork() to figure out the |
690 | * state we're undoing. |
691 | * |
692 | * Parameters: child_proc Child process |
693 | * retval System call return value array |
694 | * rval Return value to present to parent |
695 | * |
696 | * Returns: void |
697 | * |
698 | * Notes: The caller resumes or exits the parent, as appropriate, after |
699 | * calling this function. |
700 | */ |
701 | void |
702 | vfork_return(proc_t child_proc, int32_t *retval, int rval) |
703 | { |
704 | task_t parent_task = get_threadtask(child_proc->p_vforkact); |
705 | proc_t parent_proc = get_bsdtask_info(parent_task); |
706 | thread_t th = current_thread(); |
707 | uthread_t uth = get_bsdthread_info(th); |
708 | |
709 | act_thread_catt(uth->uu_userstate); |
710 | |
711 | /* clear vfork state in parent proc structure */ |
712 | proc_vfork_end(parent_proc); |
713 | |
714 | /* REPATRIATE PARENT TASK, THREAD, UTHREAD */ |
715 | uth->uu_userstate = 0; |
716 | uth->uu_flag &= ~UT_VFORK; |
717 | /* restore thread-set-id state */ |
718 | if (uth->uu_flag & UT_WASSETUID) { |
719 | uth->uu_flag |= UT_SETUID; |
720 | uth->uu_flag &= UT_WASSETUID; |
721 | } |
722 | uth->uu_proc = 0; |
723 | uth->uu_sigmask = uth->uu_vforkmask; |
724 | |
725 | proc_lock(child_proc); |
726 | child_proc->p_lflag &= ~P_LINVFORK; |
727 | child_proc->p_vforkact = 0; |
728 | proc_unlock(child_proc); |
729 | |
730 | thread_set_parent(th, rval); |
731 | |
732 | if (retval) { |
733 | retval[0] = rval; |
734 | retval[1] = 0; /* mark parent */ |
735 | } |
736 | } |
737 | |
738 | |
739 | /* |
740 | * fork_create_child |
741 | * |
742 | * Description: Common operations associated with the creation of a child |
743 | * process |
744 | * |
745 | * Parameters: parent_task parent task |
746 | * parent_coalitions parent's set of coalitions |
747 | * child_proc child process |
748 | * inherit_memory TRUE, if the parents address space is |
749 | * to be inherited by the child |
750 | * is_64bit_addr TRUE, if the child being created will |
751 | * be associated with a 64 bit address space |
752 | * is_64bit_data TRUE if the child being created will use a |
753 | 64-bit register state |
754 | * in_exec TRUE, if called from execve or posix spawn set exec |
755 | * FALSE, if called from fork or vfexec |
756 | * |
757 | * Note: This code is called in the fork() case, from the execve() call |
758 | * graph, if implementing an execve() following a vfork(), from |
759 | * the posix_spawn() call graph (which implicitly includes a |
760 | * vfork() equivalent call, and in the system bootstrap case. |
761 | * |
762 | * It creates a new task and thread (and as a side effect of the |
763 | * thread creation, a uthread) in the parent coalition set, which is |
764 | * then associated with the process 'child'. If the parent |
765 | * process address space is to be inherited, then a flag |
766 | * indicates that the newly created task should inherit this from |
767 | * the child task. |
768 | * |
769 | * As a special concession to bootstrapping the initial process |
770 | * in the system, it's possible for 'parent_task' to be TASK_NULL; |
771 | * in this case, 'inherit_memory' MUST be FALSE. |
772 | */ |
773 | thread_t |
774 | fork_create_child(task_t parent_task, |
775 | coalition_t *parent_coalitions, |
776 | proc_t child_proc, |
777 | int inherit_memory, |
778 | int is_64bit_addr, |
779 | int is_64bit_data, |
780 | int in_exec) |
781 | { |
782 | thread_t child_thread = NULL; |
783 | task_t child_task; |
784 | kern_return_t result; |
785 | |
786 | /* Create a new task for the child process */ |
787 | result = task_create_internal(parent_task, |
788 | parent_coalitions, |
789 | inherit_memory, |
790 | is_64bit_addr, |
791 | is_64bit_data, |
792 | TF_LRETURNWAIT | TF_LRETURNWAITER, /* All created threads will wait in task_wait_to_return */ |
793 | in_exec ? TPF_EXEC_COPY : TPF_NONE, /* Mark the task exec copy if in execve */ |
794 | &child_task); |
795 | if (result != KERN_SUCCESS) { |
796 | printf("%s: task_create_internal failed. Code: %d\n" , |
797 | __func__, result); |
798 | goto bad; |
799 | } |
800 | |
801 | if (!in_exec) { |
802 | /* |
803 | * Set the child process task to the new task if not in exec, |
804 | * will set the task for exec case in proc_exec_switch_task after image activation. |
805 | */ |
806 | child_proc->task = child_task; |
807 | } |
808 | |
809 | /* Set child task process to child proc */ |
810 | set_bsdtask_info(child_task, child_proc); |
811 | |
812 | /* Propagate CPU limit timer from parent */ |
813 | if (timerisset(&child_proc->p_rlim_cpu)) |
814 | task_vtimer_set(child_task, TASK_VTIMER_RLIM); |
815 | |
816 | /* |
817 | * Set child process BSD visible scheduler priority if nice value |
818 | * inherited from parent |
819 | */ |
820 | if (child_proc->p_nice != 0) |
821 | resetpriority(child_proc); |
822 | |
823 | /* |
824 | * Create a new thread for the child process |
825 | * The new thread is waiting on the event triggered by 'task_clear_return_wait' |
826 | */ |
827 | result = thread_create_waiting(child_task, |
828 | (thread_continue_t)task_wait_to_return, |
829 | task_get_return_wait_event(child_task), |
830 | &child_thread); |
831 | |
832 | if (result != KERN_SUCCESS) { |
833 | printf("%s: thread_create failed. Code: %d\n" , |
834 | __func__, result); |
835 | task_deallocate(child_task); |
836 | child_task = NULL; |
837 | } |
838 | |
839 | /* |
840 | * Tag thread as being the first thread in its task. |
841 | */ |
842 | thread_set_tag(child_thread, THREAD_TAG_MAINTHREAD); |
843 | |
844 | bad: |
845 | thread_yield_internal(1); |
846 | |
847 | return(child_thread); |
848 | } |
849 | |
850 | |
851 | /* |
852 | * fork |
853 | * |
854 | * Description: fork system call. |
855 | * |
856 | * Parameters: parent Parent process to fork |
857 | * uap (void) [unused] |
858 | * retval Return value |
859 | * |
860 | * Returns: 0 Success |
861 | * EAGAIN Resource unavailable, try again |
862 | * |
863 | * Notes: Attempts to create a new child process which inherits state |
864 | * from the parent process. If successful, the call returns |
865 | * having created an initially suspended child process with an |
866 | * extra Mach task and thread reference, for which the thread |
867 | * is initially suspended. Until we resume the child process, |
868 | * it is not yet running. |
869 | * |
870 | * The return information to the child is contained in the |
871 | * thread state structure of the new child, and does not |
872 | * become visible to the child through a normal return process, |
873 | * since it never made the call into the kernel itself in the |
874 | * first place. |
875 | * |
876 | * After resuming the thread, this function returns directly to |
877 | * the parent process which invoked the fork() system call. |
878 | * |
879 | * Important: The child thread_resume occurs before the parent returns; |
880 | * depending on scheduling latency, this means that it is not |
881 | * deterministic as to whether the parent or child is scheduled |
882 | * to run first. It is entirely possible that the child could |
883 | * run to completion prior to the parent running. |
884 | */ |
885 | int |
886 | fork(proc_t parent_proc, __unused struct fork_args *uap, int32_t *retval) |
887 | { |
888 | thread_t child_thread; |
889 | int err; |
890 | |
891 | retval[1] = 0; /* flag parent return for user space */ |
892 | |
893 | if ((err = fork1(parent_proc, &child_thread, PROC_CREATE_FORK, NULL)) == 0) { |
894 | task_t child_task; |
895 | proc_t child_proc; |
896 | |
897 | /* Return to the parent */ |
898 | child_proc = (proc_t)get_bsdthreadtask_info(child_thread); |
899 | retval[0] = child_proc->p_pid; |
900 | |
901 | /* |
902 | * Drop the signal lock on the child which was taken on our |
903 | * behalf by forkproc()/cloneproc() to prevent signals being |
904 | * received by the child in a partially constructed state. |
905 | */ |
906 | proc_signalend(child_proc, 0); |
907 | proc_transend(child_proc, 0); |
908 | |
909 | /* flag the fork has occurred */ |
910 | proc_knote(parent_proc, NOTE_FORK | child_proc->p_pid); |
911 | DTRACE_PROC1(create, proc_t, child_proc); |
912 | |
913 | #if CONFIG_DTRACE |
914 | if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) |
915 | (*dtrace_proc_waitfor_hook)(child_proc); |
916 | #endif |
917 | |
918 | /* "Return" to the child */ |
919 | task_clear_return_wait(get_threadtask(child_thread)); |
920 | |
921 | /* drop the extra references we got during the creation */ |
922 | if ((child_task = (task_t)get_threadtask(child_thread)) != NULL) { |
923 | task_deallocate(child_task); |
924 | } |
925 | thread_deallocate(child_thread); |
926 | } |
927 | |
928 | return(err); |
929 | } |
930 | |
931 | |
932 | /* |
933 | * cloneproc |
934 | * |
935 | * Description: Create a new process from a specified process. |
936 | * |
937 | * Parameters: parent_task The parent task to be cloned, or |
938 | * TASK_NULL is task characteristics |
939 | * are not to be inherited |
940 | * be cloned, or TASK_NULL if the new |
941 | * task is not to inherit the VM |
942 | * characteristics of the parent |
943 | * parent_proc The parent process to be cloned |
944 | * inherit_memory True if the child is to inherit |
945 | * memory from the parent; if this is |
946 | * non-NULL, then the parent_task must |
947 | * also be non-NULL |
948 | * memstat_internal Whether to track the process in the |
949 | * jetsam priority list (if configured) |
950 | * |
951 | * Returns: !NULL pointer to new child thread |
952 | * NULL Failure (unspecified) |
953 | * |
954 | * Note: On return newly created child process has signal lock held |
955 | * to block delivery of signal to it if called with lock set. |
956 | * fork() code needs to explicity remove this lock before |
957 | * signals can be delivered |
958 | * |
959 | * In the case of bootstrap, this function can be called from |
960 | * bsd_utaskbootstrap() in order to bootstrap the first process; |
961 | * the net effect is to provide a uthread structure for the |
962 | * kernel process associated with the kernel task. |
963 | * |
964 | * XXX: Tristating using the value parent_task as the major key |
965 | * and inherit_memory as the minor key is something we should |
966 | * refactor later; we owe the current semantics, ultimately, |
967 | * to the semantics of task_create_internal. For now, we will |
968 | * live with this being somewhat awkward. |
969 | */ |
970 | thread_t |
971 | cloneproc(task_t parent_task, coalition_t *parent_coalitions, proc_t parent_proc, int inherit_memory, int memstat_internal) |
972 | { |
973 | #if !CONFIG_MEMORYSTATUS |
974 | #pragma unused(memstat_internal) |
975 | #endif |
976 | task_t child_task; |
977 | proc_t child_proc; |
978 | thread_t child_thread = NULL; |
979 | |
980 | if ((child_proc = forkproc(parent_proc)) == NULL) { |
981 | /* Failed to allocate new process */ |
982 | goto bad; |
983 | } |
984 | |
985 | /* |
986 | * In the case where the parent_task is TASK_NULL (during the init path) |
987 | * we make the assumption that the register size will be the same as the |
988 | * address space size since there's no way to determine the possible |
989 | * register size until an image is exec'd. |
990 | * |
991 | * The only architecture that has different address space and register sizes |
992 | * (arm64_32) isn't being used within kernel-space, so the above assumption |
993 | * always holds true for the init path. |
994 | */ |
995 | const int parent_64bit_addr = parent_proc->p_flag & P_LP64; |
996 | const int parent_64bit_data = (parent_task == TASK_NULL) ? parent_64bit_addr : task_get_64bit_data(parent_task); |
997 | |
998 | child_thread = fork_create_child(parent_task, |
999 | parent_coalitions, |
1000 | child_proc, |
1001 | inherit_memory, |
1002 | parent_64bit_addr, |
1003 | parent_64bit_data, |
1004 | FALSE); |
1005 | |
1006 | if (child_thread == NULL) { |
1007 | /* |
1008 | * Failed to create thread; now we must deconstruct the new |
1009 | * process previously obtained from forkproc(). |
1010 | */ |
1011 | forkproc_free(child_proc); |
1012 | goto bad; |
1013 | } |
1014 | |
1015 | child_task = get_threadtask(child_thread); |
1016 | if (parent_64bit_addr) { |
1017 | OSBitOrAtomic(P_LP64, (UInt32 *)&child_proc->p_flag); |
1018 | } else { |
1019 | OSBitAndAtomic(~((uint32_t)P_LP64), (UInt32 *)&child_proc->p_flag); |
1020 | } |
1021 | |
1022 | #if CONFIG_MEMORYSTATUS |
1023 | if (memstat_internal) { |
1024 | proc_list_lock(); |
1025 | child_proc->p_memstat_state |= P_MEMSTAT_INTERNAL; |
1026 | proc_list_unlock(); |
1027 | } |
1028 | #endif |
1029 | |
1030 | /* make child visible */ |
1031 | pinsertchild(parent_proc, child_proc); |
1032 | |
1033 | /* |
1034 | * Make child runnable, set start time. |
1035 | */ |
1036 | child_proc->p_stat = SRUN; |
1037 | bad: |
1038 | return(child_thread); |
1039 | } |
1040 | |
1041 | |
1042 | /* |
1043 | * Destroy a process structure that resulted from a call to forkproc(), but |
1044 | * which must be returned to the system because of a subsequent failure |
1045 | * preventing it from becoming active. |
1046 | * |
1047 | * Parameters: p The incomplete process from forkproc() |
1048 | * |
1049 | * Returns: (void) |
1050 | * |
1051 | * Note: This function should only be used in an error handler following |
1052 | * a call to forkproc(). |
1053 | * |
1054 | * Operations occur in reverse order of those in forkproc(). |
1055 | */ |
1056 | void |
1057 | forkproc_free(proc_t p) |
1058 | { |
1059 | #if CONFIG_PERSONAS |
1060 | persona_proc_drop(p); |
1061 | #endif /* CONFIG_PERSONAS */ |
1062 | |
1063 | #if PSYNCH |
1064 | pth_proc_hashdelete(p); |
1065 | #endif /* PSYNCH */ |
1066 | |
1067 | /* We held signal and a transition locks; drop them */ |
1068 | proc_signalend(p, 0); |
1069 | proc_transend(p, 0); |
1070 | |
1071 | /* |
1072 | * If we have our own copy of the resource limits structure, we |
1073 | * need to free it. If it's a shared copy, we need to drop our |
1074 | * reference on it. |
1075 | */ |
1076 | proc_limitdrop(p, 0); |
1077 | p->p_limit = NULL; |
1078 | |
1079 | #if SYSV_SHM |
1080 | /* Need to drop references to the shared memory segment(s), if any */ |
1081 | if (p->vm_shm) { |
1082 | /* |
1083 | * Use shmexec(): we have no address space, so no mappings |
1084 | * |
1085 | * XXX Yes, the routine is badly named. |
1086 | */ |
1087 | shmexec(p); |
1088 | } |
1089 | #endif |
1090 | |
1091 | /* Need to undo the effects of the fdcopy(), if any */ |
1092 | fdfree(p); |
1093 | |
1094 | /* |
1095 | * Drop the reference on a text vnode pointer, if any |
1096 | * XXX This code is broken in forkproc(); see <rdar://4256419>; |
1097 | * XXX if anyone ever uses this field, we will be extremely unhappy. |
1098 | */ |
1099 | if (p->p_textvp) { |
1100 | vnode_rele(p->p_textvp); |
1101 | p->p_textvp = NULL; |
1102 | } |
1103 | |
1104 | /* Stop the profiling clock */ |
1105 | stopprofclock(p); |
1106 | |
1107 | /* Update the audit session proc count */ |
1108 | AUDIT_SESSION_PROCEXIT(p); |
1109 | |
1110 | #if CONFIG_FINE_LOCK_GROUPS |
1111 | lck_mtx_destroy(&p->p_mlock, proc_mlock_grp); |
1112 | lck_mtx_destroy(&p->p_fdmlock, proc_fdmlock_grp); |
1113 | lck_mtx_destroy(&p->p_ucred_mlock, proc_ucred_mlock_grp); |
1114 | #if CONFIG_DTRACE |
1115 | lck_mtx_destroy(&p->p_dtrace_sprlock, proc_lck_grp); |
1116 | #endif |
1117 | lck_spin_destroy(&p->p_slock, proc_slock_grp); |
1118 | #else /* CONFIG_FINE_LOCK_GROUPS */ |
1119 | lck_mtx_destroy(&p->p_mlock, proc_lck_grp); |
1120 | lck_mtx_destroy(&p->p_fdmlock, proc_lck_grp); |
1121 | lck_mtx_destroy(&p->p_ucred_mlock, proc_lck_grp); |
1122 | #if CONFIG_DTRACE |
1123 | lck_mtx_destroy(&p->p_dtrace_sprlock, proc_lck_grp); |
1124 | #endif |
1125 | lck_spin_destroy(&p->p_slock, proc_lck_grp); |
1126 | #endif /* CONFIG_FINE_LOCK_GROUPS */ |
1127 | |
1128 | /* Release the credential reference */ |
1129 | kauth_cred_unref(&p->p_ucred); |
1130 | |
1131 | proc_list_lock(); |
1132 | /* Decrement the count of processes in the system */ |
1133 | nprocs--; |
1134 | |
1135 | /* Take it out of process hash */ |
1136 | LIST_REMOVE(p, p_hash); |
1137 | |
1138 | proc_list_unlock(); |
1139 | |
1140 | thread_call_free(p->p_rcall); |
1141 | |
1142 | /* Free allocated memory */ |
1143 | FREE_ZONE(p->p_sigacts, sizeof *p->p_sigacts, M_SIGACTS); |
1144 | p->p_sigacts = NULL; |
1145 | FREE_ZONE(p->p_stats, sizeof *p->p_stats, M_PSTATS); |
1146 | p->p_stats = NULL; |
1147 | |
1148 | proc_checkdeadrefs(p); |
1149 | FREE_ZONE(p, sizeof *p, M_PROC); |
1150 | } |
1151 | |
1152 | |
1153 | /* |
1154 | * forkproc |
1155 | * |
1156 | * Description: Create a new process structure, given a parent process |
1157 | * structure. |
1158 | * |
1159 | * Parameters: parent_proc The parent process |
1160 | * |
1161 | * Returns: !NULL The new process structure |
1162 | * NULL Error (insufficient free memory) |
1163 | * |
1164 | * Note: When successful, the newly created process structure is |
1165 | * partially initialized; if a caller needs to deconstruct the |
1166 | * returned structure, they must call forkproc_free() to do so. |
1167 | */ |
1168 | proc_t |
1169 | forkproc(proc_t parent_proc) |
1170 | { |
1171 | proc_t child_proc; /* Our new process */ |
1172 | static int nextpid = 0, pidwrap = 0, nextpidversion = 0; |
1173 | static uint64_t nextuniqueid = 0; |
1174 | int error = 0; |
1175 | struct session *sessp; |
1176 | uthread_t parent_uthread = (uthread_t)get_bsdthread_info(current_thread()); |
1177 | |
1178 | MALLOC_ZONE(child_proc, proc_t , sizeof *child_proc, M_PROC, M_WAITOK); |
1179 | if (child_proc == NULL) { |
1180 | printf("forkproc: M_PROC zone exhausted\n" ); |
1181 | goto bad; |
1182 | } |
1183 | /* zero it out as we need to insert in hash */ |
1184 | bzero(child_proc, sizeof *child_proc); |
1185 | |
1186 | MALLOC_ZONE(child_proc->p_stats, struct pstats *, |
1187 | sizeof *child_proc->p_stats, M_PSTATS, M_WAITOK); |
1188 | if (child_proc->p_stats == NULL) { |
1189 | printf("forkproc: M_SUBPROC zone exhausted (p_stats)\n" ); |
1190 | FREE_ZONE(child_proc, sizeof *child_proc, M_PROC); |
1191 | child_proc = NULL; |
1192 | goto bad; |
1193 | } |
1194 | MALLOC_ZONE(child_proc->p_sigacts, struct sigacts *, |
1195 | sizeof *child_proc->p_sigacts, M_SIGACTS, M_WAITOK); |
1196 | if (child_proc->p_sigacts == NULL) { |
1197 | printf("forkproc: M_SUBPROC zone exhausted (p_sigacts)\n" ); |
1198 | FREE_ZONE(child_proc->p_stats, sizeof *child_proc->p_stats, M_PSTATS); |
1199 | child_proc->p_stats = NULL; |
1200 | FREE_ZONE(child_proc, sizeof *child_proc, M_PROC); |
1201 | child_proc = NULL; |
1202 | goto bad; |
1203 | } |
1204 | |
1205 | /* allocate a callout for use by interval timers */ |
1206 | child_proc->p_rcall = thread_call_allocate((thread_call_func_t)realitexpire, child_proc); |
1207 | if (child_proc->p_rcall == NULL) { |
1208 | FREE_ZONE(child_proc->p_sigacts, sizeof *child_proc->p_sigacts, M_SIGACTS); |
1209 | child_proc->p_sigacts = NULL; |
1210 | FREE_ZONE(child_proc->p_stats, sizeof *child_proc->p_stats, M_PSTATS); |
1211 | child_proc->p_stats = NULL; |
1212 | FREE_ZONE(child_proc, sizeof *child_proc, M_PROC); |
1213 | child_proc = NULL; |
1214 | goto bad; |
1215 | } |
1216 | |
1217 | |
1218 | /* |
1219 | * Find an unused PID. |
1220 | */ |
1221 | |
1222 | proc_list_lock(); |
1223 | |
1224 | nextpid++; |
1225 | retry: |
1226 | /* |
1227 | * If the process ID prototype has wrapped around, |
1228 | * restart somewhat above 0, as the low-numbered procs |
1229 | * tend to include daemons that don't exit. |
1230 | */ |
1231 | if (nextpid >= PID_MAX) { |
1232 | nextpid = 100; |
1233 | pidwrap = 1; |
1234 | } |
1235 | if (pidwrap != 0) { |
1236 | |
1237 | /* if the pid stays in hash both for zombie and runniing state */ |
1238 | if (pfind_locked(nextpid) != PROC_NULL) { |
1239 | nextpid++; |
1240 | goto retry; |
1241 | } |
1242 | |
1243 | if (pgfind_internal(nextpid) != PGRP_NULL) { |
1244 | nextpid++; |
1245 | goto retry; |
1246 | } |
1247 | if (session_find_internal(nextpid) != SESSION_NULL) { |
1248 | nextpid++; |
1249 | goto retry; |
1250 | } |
1251 | } |
1252 | nprocs++; |
1253 | child_proc->p_pid = nextpid; |
1254 | child_proc->p_responsible_pid = nextpid; /* initially responsible for self */ |
1255 | child_proc->p_idversion = nextpidversion++; |
1256 | /* kernel process is handcrafted and not from fork, so start from 1 */ |
1257 | child_proc->p_uniqueid = ++nextuniqueid; |
1258 | #if 1 |
1259 | if (child_proc->p_pid != 0) { |
1260 | if (pfind_locked(child_proc->p_pid) != PROC_NULL) |
1261 | panic("proc in the list already\n" ); |
1262 | } |
1263 | #endif |
1264 | /* Insert in the hash */ |
1265 | child_proc->p_listflag |= (P_LIST_INHASH | P_LIST_INCREATE); |
1266 | LIST_INSERT_HEAD(PIDHASH(child_proc->p_pid), child_proc, p_hash); |
1267 | proc_list_unlock(); |
1268 | |
1269 | if (child_proc->p_uniqueid == startup_serial_num_procs) { |
1270 | /* |
1271 | * Turn off startup serial logging now that we have reached |
1272 | * the defined number of startup processes. |
1273 | */ |
1274 | startup_serial_logging_active = false; |
1275 | } |
1276 | |
1277 | /* |
1278 | * We've identified the PID we are going to use; initialize the new |
1279 | * process structure. |
1280 | */ |
1281 | child_proc->p_stat = SIDL; |
1282 | child_proc->p_pgrpid = PGRPID_DEAD; |
1283 | |
1284 | /* |
1285 | * The zero'ing of the proc was at the allocation time due to need |
1286 | * for insertion to hash. Copy the section that is to be copied |
1287 | * directly from the parent. |
1288 | */ |
1289 | bcopy(&parent_proc->p_startcopy, &child_proc->p_startcopy, |
1290 | (unsigned) ((caddr_t)&child_proc->p_endcopy - (caddr_t)&child_proc->p_startcopy)); |
1291 | |
1292 | /* |
1293 | * Some flags are inherited from the parent. |
1294 | * Duplicate sub-structures as needed. |
1295 | * Increase reference counts on shared objects. |
1296 | * The p_stats and p_sigacts substructs are set in vm_fork. |
1297 | */ |
1298 | #if !CONFIG_EMBEDDED |
1299 | child_proc->p_flag = (parent_proc->p_flag & (P_LP64 | P_DISABLE_ASLR | P_DELAYIDLESLEEP | P_SUGID)); |
1300 | #else /* !CONFIG_EMBEDDED */ |
1301 | child_proc->p_flag = (parent_proc->p_flag & (P_LP64 | P_DISABLE_ASLR | P_SUGID)); |
1302 | #endif /* !CONFIG_EMBEDDED */ |
1303 | if (parent_proc->p_flag & P_PROFIL) |
1304 | startprofclock(child_proc); |
1305 | |
1306 | child_proc->p_vfs_iopolicy = (parent_proc->p_vfs_iopolicy & (P_VFS_IOPOLICY_VALID_MASK)); |
1307 | |
1308 | /* |
1309 | * Note that if the current thread has an assumed identity, this |
1310 | * credential will be granted to the new process. |
1311 | */ |
1312 | child_proc->p_ucred = kauth_cred_get_with_ref(); |
1313 | /* update cred on proc */ |
1314 | PROC_UPDATE_CREDS_ONPROC(child_proc); |
1315 | /* update audit session proc count */ |
1316 | AUDIT_SESSION_PROCNEW(child_proc); |
1317 | |
1318 | #if CONFIG_FINE_LOCK_GROUPS |
1319 | lck_mtx_init(&child_proc->p_mlock, proc_mlock_grp, proc_lck_attr); |
1320 | lck_mtx_init(&child_proc->p_fdmlock, proc_fdmlock_grp, proc_lck_attr); |
1321 | lck_mtx_init(&child_proc->p_ucred_mlock, proc_ucred_mlock_grp, proc_lck_attr); |
1322 | #if CONFIG_DTRACE |
1323 | lck_mtx_init(&child_proc->p_dtrace_sprlock, proc_lck_grp, proc_lck_attr); |
1324 | #endif |
1325 | lck_spin_init(&child_proc->p_slock, proc_slock_grp, proc_lck_attr); |
1326 | #else /* !CONFIG_FINE_LOCK_GROUPS */ |
1327 | lck_mtx_init(&child_proc->p_mlock, proc_lck_grp, proc_lck_attr); |
1328 | lck_mtx_init(&child_proc->p_fdmlock, proc_lck_grp, proc_lck_attr); |
1329 | lck_mtx_init(&child_proc->p_ucred_mlock, proc_lck_grp, proc_lck_attr); |
1330 | #if CONFIG_DTRACE |
1331 | lck_mtx_init(&child_proc->p_dtrace_sprlock, proc_lck_grp, proc_lck_attr); |
1332 | #endif |
1333 | lck_spin_init(&child_proc->p_slock, proc_lck_grp, proc_lck_attr); |
1334 | #endif /* !CONFIG_FINE_LOCK_GROUPS */ |
1335 | klist_init(&child_proc->p_klist); |
1336 | |
1337 | if (child_proc->p_textvp != NULLVP) { |
1338 | /* bump references to the text vnode */ |
1339 | /* Need to hold iocount across the ref call */ |
1340 | if (vnode_getwithref(child_proc->p_textvp) == 0) { |
1341 | error = vnode_ref(child_proc->p_textvp); |
1342 | vnode_put(child_proc->p_textvp); |
1343 | if (error != 0) |
1344 | child_proc->p_textvp = NULLVP; |
1345 | } |
1346 | } |
1347 | |
1348 | /* |
1349 | * Copy the parents per process open file table to the child; if |
1350 | * there is a per-thread current working directory, set the childs |
1351 | * per-process current working directory to that instead of the |
1352 | * parents. |
1353 | * |
1354 | * XXX may fail to copy descriptors to child |
1355 | */ |
1356 | child_proc->p_fd = fdcopy(parent_proc, parent_uthread->uu_cdir); |
1357 | |
1358 | #if SYSV_SHM |
1359 | if (parent_proc->vm_shm) { |
1360 | /* XXX may fail to attach shm to child */ |
1361 | (void)shmfork(parent_proc, child_proc); |
1362 | } |
1363 | #endif |
1364 | /* |
1365 | * inherit the limit structure to child |
1366 | */ |
1367 | proc_limitfork(parent_proc, child_proc); |
1368 | |
1369 | if (child_proc->p_limit->pl_rlimit[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { |
1370 | uint64_t rlim_cur = child_proc->p_limit->pl_rlimit[RLIMIT_CPU].rlim_cur; |
1371 | child_proc->p_rlim_cpu.tv_sec = (rlim_cur > __INT_MAX__) ? __INT_MAX__ : rlim_cur; |
1372 | } |
1373 | |
1374 | /* Intialize new process stats, including start time */ |
1375 | /* <rdar://6640543> non-zeroed portion contains garbage AFAICT */ |
1376 | bzero(child_proc->p_stats, sizeof(*child_proc->p_stats)); |
1377 | microtime_with_abstime(&child_proc->p_start, &child_proc->p_stats->ps_start); |
1378 | |
1379 | if (parent_proc->p_sigacts != NULL) |
1380 | (void)memcpy(child_proc->p_sigacts, |
1381 | parent_proc->p_sigacts, sizeof *child_proc->p_sigacts); |
1382 | else |
1383 | (void)memset(child_proc->p_sigacts, 0, sizeof *child_proc->p_sigacts); |
1384 | |
1385 | sessp = proc_session(parent_proc); |
1386 | if (sessp->s_ttyvp != NULL && parent_proc->p_flag & P_CONTROLT) |
1387 | OSBitOrAtomic(P_CONTROLT, &child_proc->p_flag); |
1388 | session_rele(sessp); |
1389 | |
1390 | /* |
1391 | * block all signals to reach the process. |
1392 | * no transition race should be occuring with the child yet, |
1393 | * but indicate that the process is in (the creation) transition. |
1394 | */ |
1395 | proc_signalstart(child_proc, 0); |
1396 | proc_transstart(child_proc, 0, 0); |
1397 | |
1398 | child_proc->p_pcaction = 0; |
1399 | |
1400 | TAILQ_INIT(&child_proc->p_uthlist); |
1401 | TAILQ_INIT(&child_proc->p_aio_activeq); |
1402 | TAILQ_INIT(&child_proc->p_aio_doneq); |
1403 | |
1404 | /* Inherit the parent flags for code sign */ |
1405 | child_proc->p_csflags = (parent_proc->p_csflags & ~CS_KILLED); |
1406 | |
1407 | /* |
1408 | * Copy work queue information |
1409 | * |
1410 | * Note: This should probably only happen in the case where we are |
1411 | * creating a child that is a copy of the parent; since this |
1412 | * routine is called in the non-duplication case of vfork() |
1413 | * or posix_spawn(), then this information should likely not |
1414 | * be duplicated. |
1415 | * |
1416 | * <rdar://6640553> Work queue pointers that no longer point to code |
1417 | */ |
1418 | child_proc->p_wqthread = parent_proc->p_wqthread; |
1419 | child_proc->p_threadstart = parent_proc->p_threadstart; |
1420 | child_proc->p_pthsize = parent_proc->p_pthsize; |
1421 | if ((parent_proc->p_lflag & P_LREGISTER) != 0) { |
1422 | child_proc->p_lflag |= P_LREGISTER; |
1423 | } |
1424 | child_proc->p_dispatchqueue_offset = parent_proc->p_dispatchqueue_offset; |
1425 | child_proc->p_dispatchqueue_serialno_offset = parent_proc->p_dispatchqueue_serialno_offset; |
1426 | child_proc->p_return_to_kernel_offset = parent_proc->p_return_to_kernel_offset; |
1427 | child_proc->p_mach_thread_self_offset = parent_proc->p_mach_thread_self_offset; |
1428 | child_proc->p_pth_tsd_offset = parent_proc->p_pth_tsd_offset; |
1429 | #if PSYNCH |
1430 | pth_proc_hashinit(child_proc); |
1431 | #endif /* PSYNCH */ |
1432 | |
1433 | #if CONFIG_PERSONAS |
1434 | child_proc->p_persona = NULL; |
1435 | error = persona_proc_inherit(child_proc, parent_proc); |
1436 | if (error != 0) { |
1437 | printf("forkproc: persona_proc_inherit failed (persona %d being destroyed?)\n" , persona_get_uid(parent_proc->p_persona)); |
1438 | forkproc_free(child_proc); |
1439 | child_proc = NULL; |
1440 | goto bad; |
1441 | } |
1442 | #endif |
1443 | |
1444 | #if CONFIG_MEMORYSTATUS |
1445 | /* Memorystatus init */ |
1446 | child_proc->p_memstat_state = 0; |
1447 | child_proc->p_memstat_effectivepriority = JETSAM_PRIORITY_DEFAULT; |
1448 | child_proc->p_memstat_requestedpriority = JETSAM_PRIORITY_DEFAULT; |
1449 | child_proc->p_memstat_userdata = 0; |
1450 | child_proc->p_memstat_idle_start = 0; |
1451 | child_proc->p_memstat_idle_delta = 0; |
1452 | child_proc->p_memstat_memlimit = 0; |
1453 | child_proc->p_memstat_memlimit_active = 0; |
1454 | child_proc->p_memstat_memlimit_inactive = 0; |
1455 | #if CONFIG_FREEZE |
1456 | child_proc->p_memstat_freeze_sharedanon_pages = 0; |
1457 | #endif |
1458 | child_proc->p_memstat_dirty = 0; |
1459 | child_proc->p_memstat_idledeadline = 0; |
1460 | #endif /* CONFIG_MEMORYSTATUS */ |
1461 | |
1462 | bad: |
1463 | return(child_proc); |
1464 | } |
1465 | |
1466 | void |
1467 | proc_lock(proc_t p) |
1468 | { |
1469 | LCK_MTX_ASSERT(proc_list_mlock, LCK_MTX_ASSERT_NOTOWNED); |
1470 | lck_mtx_lock(&p->p_mlock); |
1471 | } |
1472 | |
1473 | void |
1474 | proc_unlock(proc_t p) |
1475 | { |
1476 | lck_mtx_unlock(&p->p_mlock); |
1477 | } |
1478 | |
1479 | void |
1480 | proc_spinlock(proc_t p) |
1481 | { |
1482 | lck_spin_lock(&p->p_slock); |
1483 | } |
1484 | |
1485 | void |
1486 | proc_spinunlock(proc_t p) |
1487 | { |
1488 | lck_spin_unlock(&p->p_slock); |
1489 | } |
1490 | |
1491 | void |
1492 | proc_list_lock(void) |
1493 | { |
1494 | lck_mtx_lock(proc_list_mlock); |
1495 | } |
1496 | |
1497 | void |
1498 | proc_list_unlock(void) |
1499 | { |
1500 | lck_mtx_unlock(proc_list_mlock); |
1501 | } |
1502 | |
1503 | void |
1504 | proc_ucred_lock(proc_t p) |
1505 | { |
1506 | lck_mtx_lock(&p->p_ucred_mlock); |
1507 | } |
1508 | |
1509 | void |
1510 | proc_ucred_unlock(proc_t p) |
1511 | { |
1512 | lck_mtx_unlock(&p->p_ucred_mlock); |
1513 | } |
1514 | |
1515 | #include <kern/zalloc.h> |
1516 | |
1517 | struct zone *uthread_zone = NULL; |
1518 | |
1519 | static lck_grp_t *rethrottle_lock_grp; |
1520 | static lck_attr_t *rethrottle_lock_attr; |
1521 | static lck_grp_attr_t *rethrottle_lock_grp_attr; |
1522 | |
1523 | static void |
1524 | uthread_zone_init(void) |
1525 | { |
1526 | assert(uthread_zone == NULL); |
1527 | |
1528 | rethrottle_lock_grp_attr = lck_grp_attr_alloc_init(); |
1529 | rethrottle_lock_grp = lck_grp_alloc_init("rethrottle" , rethrottle_lock_grp_attr); |
1530 | rethrottle_lock_attr = lck_attr_alloc_init(); |
1531 | |
1532 | uthread_zone = zinit(sizeof(struct uthread), |
1533 | thread_max * sizeof(struct uthread), |
1534 | THREAD_CHUNK * sizeof(struct uthread), |
1535 | "uthreads" ); |
1536 | } |
1537 | |
1538 | void * |
1539 | uthread_alloc(task_t task, thread_t thread, int noinherit) |
1540 | { |
1541 | proc_t p; |
1542 | uthread_t uth; |
1543 | uthread_t uth_parent; |
1544 | void *ut; |
1545 | |
1546 | if (uthread_zone == NULL) |
1547 | uthread_zone_init(); |
1548 | |
1549 | ut = (void *)zalloc(uthread_zone); |
1550 | bzero(ut, sizeof(struct uthread)); |
1551 | |
1552 | p = (proc_t) get_bsdtask_info(task); |
1553 | uth = (uthread_t)ut; |
1554 | uth->uu_thread = thread; |
1555 | |
1556 | lck_spin_init(&uth->uu_rethrottle_lock, rethrottle_lock_grp, |
1557 | rethrottle_lock_attr); |
1558 | |
1559 | /* |
1560 | * Thread inherits credential from the creating thread, if both |
1561 | * are in the same task. |
1562 | * |
1563 | * If the creating thread has no credential or is from another |
1564 | * task we can leave the new thread credential NULL. If it needs |
1565 | * one later, it will be lazily assigned from the task's process. |
1566 | */ |
1567 | uth_parent = (uthread_t)get_bsdthread_info(current_thread()); |
1568 | if ((noinherit == 0) && task == current_task() && |
1569 | uth_parent != NULL && |
1570 | IS_VALID_CRED(uth_parent->uu_ucred)) { |
1571 | /* |
1572 | * XXX The new thread is, in theory, being created in context |
1573 | * XXX of parent thread, so a direct reference to the parent |
1574 | * XXX is OK. |
1575 | */ |
1576 | kauth_cred_ref(uth_parent->uu_ucred); |
1577 | uth->uu_ucred = uth_parent->uu_ucred; |
1578 | /* the credential we just inherited is an assumed credential */ |
1579 | if (uth_parent->uu_flag & UT_SETUID) |
1580 | uth->uu_flag |= UT_SETUID; |
1581 | } else { |
1582 | /* sometimes workqueue threads are created out task context */ |
1583 | if ((task != kernel_task) && (p != PROC_NULL)) |
1584 | uth->uu_ucred = kauth_cred_proc_ref(p); |
1585 | else |
1586 | uth->uu_ucred = NOCRED; |
1587 | } |
1588 | |
1589 | |
1590 | if ((task != kernel_task) && p) { |
1591 | |
1592 | proc_lock(p); |
1593 | if (noinherit != 0) { |
1594 | /* workq threads will not inherit masks */ |
1595 | uth->uu_sigmask = ~workq_threadmask; |
1596 | } else if (uth_parent) { |
1597 | if (uth_parent->uu_flag & UT_SAS_OLDMASK) |
1598 | uth->uu_sigmask = uth_parent->uu_oldmask; |
1599 | else |
1600 | uth->uu_sigmask = uth_parent->uu_sigmask; |
1601 | } |
1602 | uth->uu_context.vc_thread = thread; |
1603 | /* |
1604 | * Do not add the uthread to proc uthlist for exec copy task, |
1605 | * since they do not hold a ref on proc. |
1606 | */ |
1607 | if (!task_is_exec_copy(task)) { |
1608 | TAILQ_INSERT_TAIL(&p->p_uthlist, uth, uu_list); |
1609 | } |
1610 | proc_unlock(p); |
1611 | |
1612 | #if CONFIG_DTRACE |
1613 | if (p->p_dtrace_ptss_pages != NULL && !task_is_exec_copy(task)) { |
1614 | uth->t_dtrace_scratch = dtrace_ptss_claim_entry(p); |
1615 | } |
1616 | #endif |
1617 | } |
1618 | |
1619 | return (ut); |
1620 | } |
1621 | |
1622 | /* |
1623 | * This routine frees the thread name field of the uthread_t structure. Split out of |
1624 | * uthread_cleanup() so thread name does not get deallocated while generating a corpse fork. |
1625 | */ |
1626 | void |
1627 | uthread_cleanup_name(void *uthread) |
1628 | { |
1629 | uthread_t uth = (uthread_t)uthread; |
1630 | |
1631 | /* |
1632 | * <rdar://17834538> |
1633 | * Set pth_name to NULL before calling free(). |
1634 | * Previously there was a race condition in the |
1635 | * case this code was executing during a stackshot |
1636 | * where the stackshot could try and copy pth_name |
1637 | * after it had been freed and before if was marked |
1638 | * as null. |
1639 | */ |
1640 | if (uth->pth_name != NULL) { |
1641 | void *pth_name = uth->pth_name; |
1642 | uth->pth_name = NULL; |
1643 | kfree(pth_name, MAXTHREADNAMESIZE); |
1644 | } |
1645 | return; |
1646 | } |
1647 | |
1648 | /* |
1649 | * This routine frees all the BSD context in uthread except the credential. |
1650 | * It does not free the uthread structure as well |
1651 | */ |
1652 | void |
1653 | uthread_cleanup(task_t task, void *uthread, void * bsd_info) |
1654 | { |
1655 | struct _select *sel; |
1656 | uthread_t uth = (uthread_t)uthread; |
1657 | proc_t p = (proc_t)bsd_info; |
1658 | |
1659 | #if PROC_REF_DEBUG |
1660 | if (__improbable(uthread_get_proc_refcount(uthread) != 0)) { |
1661 | panic("uthread_cleanup called for uthread %p with uu_proc_refcount != 0" , uthread); |
1662 | } |
1663 | #endif |
1664 | |
1665 | if (uth->uu_lowpri_window || uth->uu_throttle_info) { |
1666 | /* |
1667 | * task is marked as a low priority I/O type |
1668 | * and we've somehow managed to not dismiss the throttle |
1669 | * through the normal exit paths back to user space... |
1670 | * no need to throttle this thread since its going away |
1671 | * but we do need to update our bookeeping w/r to throttled threads |
1672 | * |
1673 | * Calling this routine will clean up any throttle info reference |
1674 | * still inuse by the thread. |
1675 | */ |
1676 | throttle_lowpri_io(0); |
1677 | } |
1678 | /* |
1679 | * Per-thread audit state should never last beyond system |
1680 | * call return. Since we don't audit the thread creation/ |
1681 | * removal, the thread state pointer should never be |
1682 | * non-NULL when we get here. |
1683 | */ |
1684 | assert(uth->uu_ar == NULL); |
1685 | |
1686 | if (uth->uu_kqr_bound) { |
1687 | kqueue_threadreq_unbind(p, uth->uu_kqr_bound); |
1688 | } |
1689 | |
1690 | sel = &uth->uu_select; |
1691 | /* cleanup the select bit space */ |
1692 | if (sel->nbytes) { |
1693 | FREE(sel->ibits, M_TEMP); |
1694 | FREE(sel->obits, M_TEMP); |
1695 | sel->nbytes = 0; |
1696 | } |
1697 | |
1698 | if (uth->uu_cdir) { |
1699 | vnode_rele(uth->uu_cdir); |
1700 | uth->uu_cdir = NULLVP; |
1701 | } |
1702 | |
1703 | if (uth->uu_wqset) { |
1704 | if (waitq_set_is_valid(uth->uu_wqset)) |
1705 | waitq_set_deinit(uth->uu_wqset); |
1706 | FREE(uth->uu_wqset, M_SELECT); |
1707 | uth->uu_wqset = NULL; |
1708 | uth->uu_wqstate_sz = 0; |
1709 | } |
1710 | |
1711 | os_reason_free(uth->uu_exit_reason); |
1712 | |
1713 | if ((task != kernel_task) && p) { |
1714 | |
1715 | if (((uth->uu_flag & UT_VFORK) == UT_VFORK) && (uth->uu_proc != PROC_NULL)) { |
1716 | vfork_exit_internal(uth->uu_proc, 0, 1); |
1717 | } |
1718 | /* |
1719 | * Remove the thread from the process list and |
1720 | * transfer [appropriate] pending signals to the process. |
1721 | * Do not remove the uthread from proc uthlist for exec |
1722 | * copy task, since they does not have a ref on proc and |
1723 | * would not have been added to the list. |
1724 | */ |
1725 | if (get_bsdtask_info(task) == p && !task_is_exec_copy(task)) { |
1726 | proc_lock(p); |
1727 | |
1728 | TAILQ_REMOVE(&p->p_uthlist, uth, uu_list); |
1729 | p->p_siglist |= (uth->uu_siglist & execmask & (~p->p_sigignore | sigcantmask)); |
1730 | proc_unlock(p); |
1731 | } |
1732 | #if CONFIG_DTRACE |
1733 | struct dtrace_ptss_page_entry *tmpptr = uth->t_dtrace_scratch; |
1734 | uth->t_dtrace_scratch = NULL; |
1735 | if (tmpptr != NULL && !task_is_exec_copy(task)) { |
1736 | dtrace_ptss_release_entry(p, tmpptr); |
1737 | } |
1738 | #endif |
1739 | } |
1740 | } |
1741 | |
1742 | /* This routine releases the credential stored in uthread */ |
1743 | void |
1744 | uthread_cred_free(void *uthread) |
1745 | { |
1746 | uthread_t uth = (uthread_t)uthread; |
1747 | |
1748 | /* and free the uthread itself */ |
1749 | if (IS_VALID_CRED(uth->uu_ucred)) { |
1750 | kauth_cred_t oldcred = uth->uu_ucred; |
1751 | uth->uu_ucred = NOCRED; |
1752 | kauth_cred_unref(&oldcred); |
1753 | } |
1754 | } |
1755 | |
1756 | /* This routine frees the uthread structure held in thread structure */ |
1757 | void |
1758 | uthread_zone_free(void *uthread) |
1759 | { |
1760 | uthread_t uth = (uthread_t)uthread; |
1761 | |
1762 | if (uth->t_tombstone) { |
1763 | kfree(uth->t_tombstone, sizeof(struct doc_tombstone)); |
1764 | uth->t_tombstone = NULL; |
1765 | } |
1766 | |
1767 | lck_spin_destroy(&uth->uu_rethrottle_lock, rethrottle_lock_grp); |
1768 | |
1769 | uthread_cleanup_name(uthread); |
1770 | /* and free the uthread itself */ |
1771 | zfree(uthread_zone, uthread); |
1772 | } |
1773 | |