/* * Copyright (c) 2018-2020, Andreas Kling * * SPDX-License-Identifier: BSD-2-Clause */ #include #include #include #include #include #include #ifndef _DYNAMIC_LOADER extern "C" { extern size_t __stack_chk_guard; 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; arc4random_buf(&__stack_chk_guard, sizeof(__stack_chk_guard)); if (__stack_chk_guard == 0) __stack_chk_guard = original_stack_chk; environ = env; __environ_is_malloced = false; __begin_atexit_locking(); _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