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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include "logd.h"
void *__stack_chk_guard = 0;
/* Initialize the canary with a random value from /dev/urandom.
* If that fails, use the "terminator canary". */
static void __attribute__ ((constructor))
__guard_setup(void)
{
int fd;
fd = open("/dev/urandom", O_RDONLY);
if (fd != -1) {
ssize_t len = read(fd, &__stack_chk_guard,
sizeof(__stack_chk_guard));
close(fd);
if (len == sizeof(__stack_chk_guard))
return;
}
/* If that failed, switch to 'terminator canary' */
((unsigned char *)&__stack_chk_guard)[0] = 0;
((unsigned char *)&__stack_chk_guard)[1] = 0;
((unsigned char *)&__stack_chk_guard)[2] = '\n';
((unsigned char *)&__stack_chk_guard)[3] = 255;
}
/* This is the crash handler.
* Does a best effort at logging and calls _exit to terminate
* the process immediately (without atexit handlers, etc.) */
void __stack_chk_fail(void)
{
struct sigaction sa;
sigset_t sigmask;
static const char message[] = "stack corruption detected: aborted";
char path[PATH_MAX];
int count;
/* Immediately block all (but SIGABRT) signal handlers from running code */
sigfillset(&sigmask);
sigdelset(&sigmask, SIGABRT);
sigprocmask(SIG_BLOCK, &sigmask, NULL);
/* Use /proc/self/exe link to obtain the program name for logging
* purposes. If it's not available, we set it to "<unknown>" */
if ((count = readlink("/proc/self/exe", path, sizeof(path) - 1)) == -1) {
strlcpy(path, "<unknown>", sizeof(path));
} else {
path[count] = '\0';
}
/* Do a best effort at logging. This ends up calling writev(2) */
__libc_android_log_print(ANDROID_LOG_FATAL, path, message);
/* Make sure there is no default action for SIGABRT */
bzero(&sa, sizeof(struct sigaction));
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sa.sa_handler = SIG_DFL;
sigaction(SIGABRT, &sa, NULL);
/* Terminate the process and exit immediately */
kill(getpid(), SIGABRT);
_exit(127);
}
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