ladybird/Userland/Tests/LibC/stack-smash.cpp

/*
 * Copyright (c) 2021, Brian Gianforcaro <b.gianfo@gmail.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. 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 HOLDER 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 <cstdio>

// Note: Needs to be 'noline' so stack canary isn't optimized out.
static void __attribute__((noinline)) smasher(char* string)
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Warray-bounds"
    for (int i = 0; i < 256; i++) {
        string[i] = 'A';
    }
#pragma GCC diagnostic pop
}

// Note: Needs to be 'noline' so stack canary isn't optimized out.
static void __attribute__((noinline)) stack_to_smash()
{
    char string[8] = {};
    smasher(string);
}

int main()
{
    puts("[+] Starting the stack smash...");
    stack_to_smash();
    puts("[+] Stack smash wasn't detected!");

    return 0;
}