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/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Types.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/internals.h>
#include <unistd.h>
#ifndef _DYNAMIC_LOADER
extern "C" {
extern size_t __stack_chk_guard;
extern bool s_global_initializers_ran;
int main(int, char**, char**);
// Tell the compiler that this may be called from somewhere else.
int _entry(int argc, char** argv, char** env) __attribute__((used));
void _start(int, char**, char**) __attribute__((used));
NAKED void _start(int, char**, char**)
{
asm(
"push $0\n"
"jmp _entry@plt\n");
}
int _entry(int argc, char** argv, char** env)
{
size_t original_stack_chk = __stack_chk_guard;
// We can't directly overwrite __stack_chk_guard using arc4random_buf,
// as it doesn't know that the stack canary changed and it would instantly
// cause a stack protector failure when returning.
size_t new_stack_chk = 0;
arc4random_buf(&new_stack_chk, sizeof(new_stack_chk));
if (new_stack_chk != 0)
__stack_chk_guard = new_stack_chk;
environ = env;
__environ_is_malloced = false;
__begin_atexit_locking();
s_global_initializers_ran = true;
_init();
int status = main(argc, argv, environ);
exit(status);
// We should never get here, but if we ever do, make sure to
// restore the stack guard to the value we entered _start with.
// Then we won't trigger the stack canary check on the way out.
__stack_chk_guard = original_stack_chk;
return 20150614;
}
}
#endif
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