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/* $OpenBSD: rthread_fork.c,v 1.23 2017/10/29 08:45:53 mpi Exp $ */ |
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/* |
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* Copyright (c) 2008 Kurt Miller <kurt@openbsd.org> |
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* Copyright (c) 2008 Philip Guenther <guenther@openbsd.org> |
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* Copyright (c) 2003 Daniel Eischen <deischen@freebsd.org> |
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* All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Neither the name of the author nor the names of any co-contributors |
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* may be used to endorse or promote products derived from this software |
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* without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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* |
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* $FreeBSD: /repoman/r/ncvs/src/lib/libc_r/uthread/uthread_atfork.c,v 1.1 2004/12/10 03:36:45 grog Exp $ |
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*/ |
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#ifndef NO_PIC |
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#include <sys/types.h> |
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#include <elf.h> |
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#pragma weak _DYNAMIC |
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#endif |
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#include <errno.h> |
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#include <pthread.h> |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <tib.h> |
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#include <unistd.h> |
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#include "rthread.h" |
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#include "rthread_cb.h" |
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/* make {fork,vfork,getthrid} call _thread_sys_{fork,vfork,getthrid} */ |
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REDIRECT_SYSCALL(fork); |
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REDIRECT_SYSCALL(vfork); |
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REDIRECT_SYSCALL(getthrid); |
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static pid_t |
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_dofork(pid_t (*sys_fork)(void)) |
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{ |
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pthread_t me; |
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pid_t newid; |
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extern int _post_threaded; |
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✗✓ |
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if (!_threads_ready) |
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return sys_fork(); |
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me = pthread_self(); |
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/* |
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* Protect important libc/ld.so critical areas across the fork call. |
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* dlclose() will grab the atexit lock via __cxa_finalize() so lock |
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* the dl_lock first. malloc()/free() can use arc4random(), so lock |
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* malloc_lock before arc4_lock |
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*/ |
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#ifndef NO_PIC |
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✓✗ |
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if (_DYNAMIC) |
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_rthread_dl_lock(0); |
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#endif |
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newid = _thread_dofork(sys_fork); |
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✗✓ |
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if (newid == 0) { |
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struct tib *tib = me->tib; |
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#ifndef NO_PIC |
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/* reinitialize the lock in the child */ |
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if (_DYNAMIC) |
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_rthread_dl_lock(2); |
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#endif |
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/* update this thread's structure */ |
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tib->tib_tid = getthrid(); |
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me->donesem.lock = _SPINLOCK_UNLOCKED; |
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me->flags_lock = _SPINLOCK_UNLOCKED; |
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/* reinit the thread list */ |
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LIST_INIT(&_thread_list); |
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LIST_INSERT_HEAD(&_thread_list, me, threads); |
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_thread_lock = _SPINLOCK_UNLOCKED; |
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/* single threaded now */ |
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__isthreaded = 0; |
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_post_threaded = 0; /* notyet... */ |
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} |
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#ifndef NO_PIC |
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✓✗ |
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else if (_DYNAMIC) |
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_rthread_dl_lock(1); |
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#endif |
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return newid; |
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} |
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pid_t |
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_thread_fork(void) |
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{ |
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return _dofork(&fork); |
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} |
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pid_t |
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_thread_vfork(void) |
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{ |
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return _dofork(&vfork); |
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} |