blob: eddd94074012bf0a86995fd08bf6682ab00f9087 [file] [log] [blame]
Elliott Hughesfc69a8a2016-03-04 11:53:09 -08001/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17// Deliberately overwrite the stack canary.
18__attribute__((noinline)) void modify_stack_protector_test() {
Elliott Hughesfc69a8a2016-03-04 11:53:09 -080019 // We can't use memset here because it's fortified, and we want to test
20 // the line of defense *after* that.
Elliott Hughes6057d182016-04-01 14:51:10 -070021 // Without volatile, the generic x86/x86-64 targets don't write to the stack.
Elliott Hughes23ce50c2022-09-27 22:37:03 +000022 // We can't make a constant change, since the existing byte might already have
23 // had that value.
24 volatile char* p = reinterpret_cast<volatile char*>(&p + 1);
25 *p = ~*p;
Elliott Hughesfc69a8a2016-03-04 11:53:09 -080026}