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1 /*
2 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * The contents of this file constitute Original Code as defined in and
7 * are subject to the Apple Public Source License Version 1.1 (the
8 * "License"). You may not use this file except in compliance with the
9 * License. Please obtain a copy of the License at
10 * http://www.apple.com/publicsource and read it before using this file.
11 *
12 * This Original Code and all software distributed under the License are
13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17 * License for the specific language governing rights and limitations
18 * under the License.
19 *
20 * @APPLE_LICENSE_HEADER_END@
21 */
22 /* Copyright (c) 1995, 1997 Apple Computer, Inc. All Rights Reserved */
23 /*
24 * Copyright (c) 1982, 1986, 1989, 1991, 1993
25 * The Regents of the University of California. All rights reserved.
26 * (c) UNIX System Laboratories, Inc.
27 * All or some portions of this file are derived from material licensed
28 * to the University of California by American Telephone and Telegraph
29 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
30 * the permission of UNIX System Laboratories, Inc.
31 *
32 * Redistribution and use in source and binary forms, with or without
33 * modification, are permitted provided that the following conditions
34 * are met:
35 * 1. Redistributions of source code must retain the above copyright
36 * notice, this list of conditions and the following disclaimer.
37 * 2. Redistributions in binary form must reproduce the above copyright
38 * notice, this list of conditions and the following disclaimer in the
39 * documentation and/or other materials provided with the distribution.
40 * 3. All advertising materials mentioning features or use of this software
41 * must display the following acknowledgement:
42 * This product includes software developed by the University of
43 * California, Berkeley and its contributors.
44 * 4. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * @(#)kern_fork.c 8.8 (Berkeley) 2/14/95
61 */
62
63 #include <kern/assert.h>
64 #include <sys/param.h>
65 #include <sys/systm.h>
66 #include <sys/filedesc.h>
67 #include <sys/kernel.h>
68 #include <sys/malloc.h>
69 #include <sys/proc_internal.h>
70 #include <sys/kauth.h>
71 #include <sys/user.h>
72 #include <sys/resourcevar.h>
73 #include <sys/vnode_internal.h>
74 #include <sys/file_internal.h>
75 #include <sys/acct.h>
76 #if KTRACE
77 #include <sys/ktrace.h>
78 #endif
79
80 #include <bsm/audit_kernel.h>
81
82 #include <mach/mach_types.h>
83 #include <kern/kern_types.h>
84 #include <kern/kalloc.h>
85 #include <kern/mach_param.h>
86 #include <kern/task.h>
87 #include <kern/zalloc.h>
88
89 #include <machine/spl.h>
90
91 #include <vm/vm_protos.h> // for vm_map_commpage64
92
93 thread_t cloneproc(struct proc *, int);
94 struct proc * forkproc(struct proc *, int);
95 thread_t procdup(struct proc *child, struct proc *parent);
96
97 #define DOFORK 0x1 /* fork() system call */
98 #define DOVFORK 0x2 /* vfork() system call */
99 static int fork1(struct proc *, long, register_t *);
100
101 /*
102 * fork system call.
103 */
104 int
105 fork(struct proc *p, __unused void *uap, register_t *retval)
106 {
107 return (fork1(p, (long)DOFORK, retval));
108 }
109
110 /*
111 * vfork system call
112 */
113 int
114 vfork(struct proc *p, void *uap, register_t *retval)
115 {
116 register struct proc * newproc;
117 register uid_t uid;
118 thread_t cur_act = (thread_t)current_thread();
119 int count;
120 task_t t;
121 uthread_t ut;
122
123 /*
124 * Although process entries are dynamically created, we still keep
125 * a global limit on the maximum number we will create. Don't allow
126 * a nonprivileged user to use the last process; don't let root
127 * exceed the limit. The variable nprocs is the current number of
128 * processes, maxproc is the limit.
129 */
130 uid = kauth_cred_get()->cr_ruid;
131 if ((nprocs >= maxproc - 1 && uid != 0) || nprocs >= maxproc) {
132 tablefull("proc");
133 retval[1] = 0;
134 return (EAGAIN);
135 }
136
137 /*
138 * Increment the count of procs running with this uid. Don't allow
139 * a nonprivileged user to exceed their current limit.
140 */
141 count = chgproccnt(uid, 1);
142 if (uid != 0 && count > p->p_rlimit[RLIMIT_NPROC].rlim_cur) {
143 (void)chgproccnt(uid, -1);
144 return (EAGAIN);
145 }
146
147 ut = (struct uthread *)get_bsdthread_info(cur_act);
148 if (ut->uu_flag & UT_VFORK) {
149 printf("vfork called recursively by %s\n", p->p_comm);
150 (void)chgproccnt(uid, -1);
151 return (EINVAL);
152 }
153 p->p_flag |= P_VFORK;
154 p->p_vforkcnt++;
155
156 /* The newly created process comes with signal lock held */
157 newproc = (struct proc *)forkproc(p,1);
158
159 AUDIT_ARG(pid, newproc->p_pid);
160
161 LIST_INSERT_AFTER(p, newproc, p_pglist);
162 newproc->p_pptr = p;
163 newproc->task = p->task;
164 LIST_INSERT_HEAD(&p->p_children, newproc, p_sibling);
165 LIST_INIT(&newproc->p_children);
166 LIST_INSERT_HEAD(&allproc, newproc, p_list);
167 LIST_INSERT_HEAD(PIDHASH(newproc->p_pid), newproc, p_hash);
168 TAILQ_INIT(& newproc->p_evlist);
169 newproc->p_stat = SRUN;
170 newproc->p_flag |= P_INVFORK;
171 newproc->p_vforkact = cur_act;
172
173 ut->uu_flag |= UT_VFORK;
174 ut->uu_proc = newproc;
175 ut->uu_userstate = (void *)act_thread_csave();
176 ut->uu_vforkmask = ut->uu_sigmask;
177
178 /* temporarily drop thread-set-id state */
179 if (ut->uu_flag & UT_SETUID) {
180 ut->uu_flag |= UT_WASSETUID;
181 ut->uu_flag &= ~UT_SETUID;
182 }
183
184 thread_set_child(cur_act, newproc->p_pid);
185
186 microtime(&newproc->p_stats->p_start);
187 newproc->p_acflag = AFORK;
188
189 /*
190 * Preserve synchronization semantics of vfork. If waiting for
191 * child to exec or exit, set P_PPWAIT on child, and sleep on our
192 * proc (in case of exit).
193 */
194 newproc->p_flag |= P_PPWAIT;
195
196 /* drop the signal lock on the child */
197 signal_unlock(newproc);
198
199 retval[0] = newproc->p_pid;
200 retval[1] = 1; /* mark child */
201
202 return (0);
203 }
204
205 /*
206 * Return to parent vfork ehread()
207 */
208 void
209 vfork_return(__unused thread_t th_act, struct proc *p, struct proc *p2,
210 register_t *retval)
211 {
212 thread_t cur_act = (thread_t)current_thread();
213 uthread_t ut;
214
215 ut = (struct uthread *)get_bsdthread_info(cur_act);
216
217 act_thread_catt(ut->uu_userstate);
218
219 /* Make sure only one at this time */
220 p->p_vforkcnt--;
221 if (p->p_vforkcnt <0)
222 panic("vfork cnt is -ve");
223 if (p->p_vforkcnt <=0)
224 p->p_flag &= ~P_VFORK;
225 ut->uu_userstate = 0;
226 ut->uu_flag &= ~UT_VFORK;
227 /* restore thread-set-id state */
228 if (ut->uu_flag & UT_WASSETUID) {
229 ut->uu_flag |= UT_SETUID;
230 ut->uu_flag &= UT_WASSETUID;
231 }
232 ut->uu_proc = 0;
233 ut->uu_sigmask = ut->uu_vforkmask;
234 p2->p_flag &= ~P_INVFORK;
235 p2->p_vforkact = (void *)0;
236
237 thread_set_parent(cur_act, p2->p_pid);
238
239 if (retval) {
240 retval[0] = p2->p_pid;
241 retval[1] = 0; /* mark parent */
242 }
243
244 return;
245 }
246
247 thread_t
248 procdup(struct proc *child, struct proc *parent)
249 {
250 thread_t thread;
251 task_t task;
252 kern_return_t result;
253
254 if (parent->task == kernel_task)
255 result = task_create_internal(TASK_NULL, FALSE, &task);
256 else
257 result = task_create_internal(parent->task, TRUE, &task);
258 if (result != KERN_SUCCESS)
259 printf("fork/procdup: task_create failed. Code: 0x%x\n", result);
260 child->task = task;
261 /* task->proc = child; */
262 set_bsdtask_info(task, child);
263 if (parent->p_flag & P_LP64) {
264 task_set_64bit(task, TRUE);
265 child->p_flag |= P_LP64;
266 #ifdef __PPC__
267 /* LP64todo - clean up this hacked mapping of commpage */
268 pmap_map_sharedpage(task, get_map_pmap(get_task_map(task)));
269 vm_map_commpage64(get_task_map(task));
270 #endif /* __PPC__ */
271 } else {
272 task_set_64bit(task, FALSE);
273 child->p_flag &= ~P_LP64;
274 }
275 if (child->p_nice != 0)
276 resetpriority(child);
277
278 result = thread_create(task, &thread);
279 if (result != KERN_SUCCESS)
280 printf("fork/procdup: thread_create failed. Code: 0x%x\n", result);
281
282 return(thread);
283 }
284
285
286 static int
287 fork1(p1, flags, retval)
288 struct proc *p1;
289 long flags;
290 register_t *retval;
291 {
292 register struct proc *p2;
293 register uid_t uid;
294 thread_t newth;
295 int count;
296 task_t t;
297
298 /*
299 * Although process entries are dynamically created, we still keep
300 * a global limit on the maximum number we will create. Don't allow
301 * a nonprivileged user to use the last process; don't let root
302 * exceed the limit. The variable nprocs is the current number of
303 * processes, maxproc is the limit.
304 */
305 uid = kauth_cred_get()->cr_ruid;
306 if ((nprocs >= maxproc - 1 && uid != 0) || nprocs >= maxproc) {
307 tablefull("proc");
308 retval[1] = 0;
309 return (EAGAIN);
310 }
311
312 /*
313 * Increment the count of procs running with this uid. Don't allow
314 * a nonprivileged user to exceed their current limit.
315 */
316 count = chgproccnt(uid, 1);
317 if (uid != 0 && count > p1->p_rlimit[RLIMIT_NPROC].rlim_cur) {
318 (void)chgproccnt(uid, -1);
319 return (EAGAIN);
320 }
321
322 /* The newly created process comes with signal lock held */
323 newth = cloneproc(p1, 1);
324 thread_dup(newth);
325 /* p2 = newth->task->proc; */
326 p2 = (struct proc *)(get_bsdtask_info(get_threadtask(newth)));
327 set_security_token(p2); /* propagate change of PID */
328
329 AUDIT_ARG(pid, p2->p_pid);
330
331 thread_set_child(newth, p2->p_pid);
332
333 microtime(&p2->p_stats->p_start);
334 p2->p_acflag = AFORK;
335
336 /*
337 * Preserve synchronization semantics of vfork. If waiting for
338 * child to exec or exit, set P_PPWAIT on child, and sleep on our
339 * proc (in case of exit).
340 */
341 if (flags == DOVFORK)
342 p2->p_flag |= P_PPWAIT;
343 /* drop the signal lock on the child */
344 signal_unlock(p2);
345
346 (void) thread_resume(newth);
347
348 /* drop the extra references we got during the creation */
349 if ((t = (task_t)get_threadtask(newth)) != NULL) {
350 task_deallocate(t);
351 }
352 thread_deallocate(newth);
353
354 KNOTE(&p1->p_klist, NOTE_FORK | p2->p_pid);
355
356 while (p2->p_flag & P_PPWAIT)
357 tsleep(p1, PWAIT, "ppwait", 0);
358
359 retval[0] = p2->p_pid;
360 retval[1] = 0; /* mark parent */
361
362 return (0);
363 }
364
365 /*
366 * cloneproc()
367 *
368 * Create a new process from a specified process.
369 * On return newly created child process has signal
370 * lock held to block delivery of signal to it if called with
371 * lock set. fork() code needs to explicity remove this lock
372 * before signals can be delivered
373 */
374 thread_t
375 cloneproc(p1, lock)
376 register struct proc *p1;
377 register int lock;
378 {
379 register struct proc *p2;
380 thread_t th;
381
382 p2 = (struct proc *)forkproc(p1,lock);
383
384
385 th = procdup(p2, p1); /* child, parent */
386
387 LIST_INSERT_AFTER(p1, p2, p_pglist);
388 p2->p_pptr = p1;
389 LIST_INSERT_HEAD(&p1->p_children, p2, p_sibling);
390 LIST_INIT(&p2->p_children);
391 LIST_INSERT_HEAD(&allproc, p2, p_list);
392 LIST_INSERT_HEAD(PIDHASH(p2->p_pid), p2, p_hash);
393 TAILQ_INIT(&p2->p_evlist);
394 /*
395 * Make child runnable, set start time.
396 */
397 p2->p_stat = SRUN;
398
399 return(th);
400 }
401
402 struct proc *
403 forkproc(p1, lock)
404 register struct proc *p1;
405 register int lock;
406 {
407 register struct proc *p2, *newproc;
408 static int nextpid = 0, pidchecked = 0;
409
410 /* Allocate new proc. */
411 MALLOC_ZONE(newproc, struct proc *,
412 sizeof *newproc, M_PROC, M_WAITOK);
413 if (newproc == NULL)
414 panic("forkproc: M_PROC zone exhausted");
415 MALLOC_ZONE(newproc->p_stats, struct pstats *,
416 sizeof *newproc->p_stats, M_SUBPROC, M_WAITOK);
417 if (newproc->p_stats == NULL)
418 panic("forkproc: M_SUBPROC zone exhausted (p_stats)");
419 MALLOC_ZONE(newproc->p_sigacts, struct sigacts *,
420 sizeof *newproc->p_sigacts, M_SUBPROC, M_WAITOK);
421 if (newproc->p_sigacts == NULL)
422 panic("forkproc: M_SUBPROC zone exhausted (p_sigacts)");
423
424 /*
425 * Find an unused process ID. We remember a range of unused IDs
426 * ready to use (from nextpid+1 through pidchecked-1).
427 */
428 nextpid++;
429 retry:
430 /*
431 * If the process ID prototype has wrapped around,
432 * restart somewhat above 0, as the low-numbered procs
433 * tend to include daemons that don't exit.
434 */
435 if (nextpid >= PID_MAX) {
436 nextpid = 100;
437 pidchecked = 0;
438 }
439 if (nextpid >= pidchecked) {
440 int doingzomb = 0;
441
442 pidchecked = PID_MAX;
443 /*
444 * Scan the active and zombie procs to check whether this pid
445 * is in use. Remember the lowest pid that's greater
446 * than nextpid, so we can avoid checking for a while.
447 */
448 p2 = allproc.lh_first;
449 again:
450 for (; p2 != 0; p2 = p2->p_list.le_next) {
451 while (p2->p_pid == nextpid ||
452 p2->p_pgrp->pg_id == nextpid ||
453 p2->p_session->s_sid == nextpid) {
454 nextpid++;
455 if (nextpid >= pidchecked)
456 goto retry;
457 }
458 if (p2->p_pid > nextpid && pidchecked > p2->p_pid)
459 pidchecked = p2->p_pid;
460 if (p2->p_pgrp && p2->p_pgrp->pg_id > nextpid &&
461 pidchecked > p2->p_pgrp->pg_id)
462 pidchecked = p2->p_pgrp->pg_id;
463 if (p2->p_session->s_sid > nextpid &&
464 pidchecked > p2->p_session->s_sid)
465 pidchecked = p2->p_session->s_sid;
466 }
467 if (!doingzomb) {
468 doingzomb = 1;
469 p2 = zombproc.lh_first;
470 goto again;
471 }
472 }
473
474 nprocs++;
475 p2 = newproc;
476 p2->p_stat = SIDL;
477 p2->p_shutdownstate = 0;
478 p2->p_pid = nextpid;
479
480 /*
481 * Make a proc table entry for the new process.
482 * Start by zeroing the section of proc that is zero-initialized,
483 * then copy the section that is copied directly from the parent.
484 */
485 bzero(&p2->p_startzero,
486 (unsigned) ((caddr_t)&p2->p_endzero - (caddr_t)&p2->p_startzero));
487 bcopy(&p1->p_startcopy, &p2->p_startcopy,
488 (unsigned) ((caddr_t)&p2->p_endcopy - (caddr_t)&p2->p_startcopy));
489 p2->vm_shm = (void *)NULL; /* Make sure it is zero */
490
491 /*
492 * Some flags are inherited from the parent.
493 * Duplicate sub-structures as needed.
494 * Increase reference counts on shared objects.
495 * The p_stats and p_sigacts substructs are set in vm_fork.
496 */
497 p2->p_flag = (p1->p_flag & (P_LP64 | P_CLASSIC | P_AFFINITY));
498 if (p1->p_flag & P_PROFIL)
499 startprofclock(p2);
500 /*
501 * Note that if the current thread has an assumed identity, this
502 * credential will be granted to the new process.
503 */
504 p2->p_ucred = kauth_cred_get_with_ref();
505
506 lck_mtx_init(&p2->p_mlock, proc_lck_grp, proc_lck_attr);
507 lck_mtx_init(&p2->p_fdmlock, proc_lck_grp, proc_lck_attr);
508 klist_init(&p2->p_klist);
509
510 /* bump references to the text vnode */
511 p2->p_textvp = p1->p_textvp;
512 if (p2->p_textvp) {
513 vnode_rele(p2->p_textvp);
514 }
515 /* XXX may fail to copy descriptors to child */
516 p2->p_fd = fdcopy(p1);
517
518 if (p1->vm_shm) {
519 /* XXX may fail to attach shm to child */
520 (void)shmfork(p1,p2);
521 }
522 /*
523 * If p_limit is still copy-on-write, bump refcnt,
524 * otherwise get a copy that won't be modified.
525 * (If PL_SHAREMOD is clear, the structure is shared
526 * copy-on-write.)
527 */
528 if (p1->p_limit->p_lflags & PL_SHAREMOD)
529 p2->p_limit = limcopy(p1->p_limit);
530 else {
531 p2->p_limit = p1->p_limit;
532 p2->p_limit->p_refcnt++;
533 }
534
535 bzero(&p2->p_stats->pstat_startzero,
536 (unsigned) ((caddr_t)&p2->p_stats->pstat_endzero -
537 (caddr_t)&p2->p_stats->pstat_startzero));
538 bcopy(&p1->p_stats->pstat_startcopy, &p2->p_stats->pstat_startcopy,
539 ((caddr_t)&p2->p_stats->pstat_endcopy -
540 (caddr_t)&p2->p_stats->pstat_startcopy));
541
542 bzero(&p2->p_stats->user_p_prof, sizeof(struct user_uprof));
543
544 if (p1->p_sigacts != NULL)
545 (void)memcpy(p2->p_sigacts,
546 p1->p_sigacts, sizeof *p2->p_sigacts);
547 else
548 (void)memset(p2->p_sigacts, 0, sizeof *p2->p_sigacts);
549
550 if (p1->p_session->s_ttyvp != NULL && p1->p_flag & P_CONTROLT)
551 p2->p_flag |= P_CONTROLT;
552
553 p2->p_argslen = p1->p_argslen;
554 p2->p_argc = p1->p_argc;
555 p2->p_xstat = 0;
556 p2->p_ru = NULL;
557
558 p2->p_debugger = 0; /* don't inherit */
559 lockinit(&p2->signal_lock, PVM, "signal", 0, 0);
560 /* block all signals to reach the process */
561 if (lock)
562 signal_lock(p2);
563 p2->sigwait = FALSE;
564 p2->sigwait_thread = NULL;
565 p2->exit_thread = NULL;
566 p2->user_stack = p1->user_stack;
567 p2->p_vforkcnt = 0;
568 p2->p_vforkact = 0;
569 p2->p_lflag = 0;
570 TAILQ_INIT(&p2->p_uthlist);
571 TAILQ_INIT(&p2->aio_activeq);
572 TAILQ_INIT(&p2->aio_doneq);
573 p2->aio_active_count = 0;
574 p2->aio_done_count = 0;
575
576 #if KTRACE
577 /*
578 * Copy traceflag and tracefile if enabled.
579 * If not inherited, these were zeroed above.
580 */
581 if (p1->p_traceflag&KTRFAC_INHERIT) {
582 p2->p_traceflag = p1->p_traceflag;
583 if ((p2->p_tracep = p1->p_tracep) != NULL) {
584 vnode_ref(p2->p_tracep);
585 }
586 }
587 #endif
588 return(p2);
589
590 }
591
592 void
593 proc_lock(proc_t p)
594 {
595 lck_mtx_lock(&p->p_mlock);
596 }
597
598 void
599 proc_unlock(proc_t p)
600 {
601 lck_mtx_unlock(&p->p_mlock);
602 }
603
604 #include <kern/zalloc.h>
605
606 struct zone *uthread_zone;
607 int uthread_zone_inited = 0;
608
609 void
610 uthread_zone_init(void)
611 {
612 if (!uthread_zone_inited) {
613 uthread_zone = zinit(sizeof(struct uthread),
614 THREAD_MAX * sizeof(struct uthread),
615 THREAD_CHUNK * sizeof(struct uthread),
616 "uthreads");
617 uthread_zone_inited = 1;
618 }
619 }
620
621 void *
622 uthread_alloc(task_t task, thread_t thr_act )
623 {
624 struct proc *p;
625 struct uthread *uth, *uth_parent;
626 void *ut;
627 boolean_t funnel_state;
628
629 if (!uthread_zone_inited)
630 uthread_zone_init();
631
632 ut = (void *)zalloc(uthread_zone);
633 bzero(ut, sizeof(struct uthread));
634
635 p = (struct proc *) get_bsdtask_info(task);
636 uth = (struct uthread *)ut;
637
638 /*
639 * Thread inherits credential from the creating thread, if both
640 * are in the same task.
641 *
642 * If the creating thread has no credential or is from another
643 * task we can leave the new thread credential NULL. If it needs
644 * one later, it will be lazily assigned from the task's process.
645 */
646 uth_parent = (struct uthread *)get_bsdthread_info(current_thread());
647 if ((task == current_task()) &&
648 (uth_parent != NULL) &&
649 (uth_parent->uu_ucred != NOCRED)) {
650 uth->uu_ucred = uth_parent->uu_ucred;
651 kauth_cred_ref(uth->uu_ucred);
652 /* the credential we just inherited is an assumed credential */
653 if (uth_parent->uu_flag & UT_SETUID)
654 uth->uu_flag |= UT_SETUID;
655 } else {
656 uth->uu_ucred = NOCRED;
657 }
658
659 if (task != kernel_task) {
660
661 funnel_state = thread_funnel_set(kernel_flock, TRUE);
662 if (uth_parent) {
663 if (uth_parent->uu_flag & UT_SAS_OLDMASK)
664 uth->uu_sigmask = uth_parent->uu_oldmask;
665 else
666 uth->uu_sigmask = uth_parent->uu_sigmask;
667 }
668 uth->uu_act = thr_act;
669 //signal_lock(p);
670 if (p) {
671 TAILQ_INSERT_TAIL(&p->p_uthlist, uth, uu_list);
672 }
673 //signal_unlock(p);
674 (void)thread_funnel_set(kernel_flock, funnel_state);
675 }
676
677 return (ut);
678 }
679
680
681 void
682 uthread_free(task_t task, void *uthread, void * bsd_info)
683 {
684 struct _select *sel;
685 struct uthread *uth = (struct uthread *)uthread;
686 struct proc * p = (struct proc *)bsd_info;
687 boolean_t funnel_state;
688
689 /*
690 * Per-thread audit state should never last beyond system
691 * call return. Since we don't audit the thread creation/
692 * removal, the thread state pointer should never be
693 * non-NULL when we get here.
694 */
695 assert(uth->uu_ar == NULL);
696
697 sel = &uth->uu_select;
698 /* cleanup the select bit space */
699 if (sel->nbytes) {
700 FREE(sel->ibits, M_TEMP);
701 FREE(sel->obits, M_TEMP);
702 }
703
704 if (sel->allocsize && sel->wqset){
705 kfree(sel->wqset, sel->allocsize);
706 sel->count = 0;
707 sel->allocsize = 0;
708 sel->wqset = 0;
709 sel->wql = 0;
710 }
711
712 if (uth->uu_ucred != NOCRED)
713 kauth_cred_rele(uth->uu_ucred);
714
715 if ((task != kernel_task) && p) {
716 funnel_state = thread_funnel_set(kernel_flock, TRUE);
717 //signal_lock(p);
718 TAILQ_REMOVE(&p->p_uthlist, uth, uu_list);
719 //signal_unlock(p);
720 (void)thread_funnel_set(kernel_flock, funnel_state);
721 }
722 /* and free the uthread itself */
723 zfree(uthread_zone, uthread);
724 }