| /* |
| * Copyright 2019 The Hafnium Authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * https://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include <stdint.h> |
| #include <stdnoreturn.h> |
| |
| #include "hf/panic.h" |
| |
| /** |
| * This is the value that is used as the stack canary. It is written to the top |
| * of the stack when entering a function and compared against the stack when |
| * exiting a function. If there is a mismatch, a failure is triggered. |
| * |
| * As the value must be the same at the beginning and end of the function, this |
| * is a global variable and there are multiple CPUs executing concurrently, this |
| * value cannot change after being initialized. |
| * |
| * TODO: initialize to a random value at boot. |
| */ |
| uint64_t __attribute__((used)) __stack_chk_guard = 0x72afaf72bad0feed; |
| |
| /** |
| * Called when the stack canary is invalid. The stack can no longer be trusted |
| * so this function must not return. |
| */ |
| noreturn void __stack_chk_fail(void) |
| { |
| panic("stack corruption"); |
| } |
