1 /* 2 * Copyright (c) 2012-2014 Wind River Systems, Inc. 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 /** 8 * @file 9 * @brief Compiler stack protection (kernel part) 10 * 11 * This module provides functions to support compiler stack protection 12 * using canaries. This feature is enabled with configuration 13 * CONFIG_STACK_CANARIES=y. 14 * 15 * When this feature is enabled, the compiler generated code refers to 16 * function __stack_chk_fail and global variable __stack_chk_guard. 17 */ 18 19 #include <zephyr/toolchain.h> /* compiler specific configurations */ 20 21 #include <zephyr/kernel_structs.h> 22 #include <zephyr/toolchain.h> 23 #include <zephyr/linker/sections.h> 24 #include <zephyr/kernel.h> 25 #include <zephyr/app_memory/app_memdomain.h> 26 27 /** 28 * 29 * @brief Stack canary error handler 30 * 31 * This function is invoked when a stack canary error is detected. 32 * 33 * @return Does not return 34 */ _StackCheckHandler(void)35void _StackCheckHandler(void) 36 { 37 /* Stack canary error is a software fatal condition; treat it as such. 38 */ 39 z_except_reason(K_ERR_STACK_CHK_FAIL); 40 CODE_UNREACHABLE; /* LCOV_EXCL_LINE */ 41 } 42 43 /* Global variable */ 44 45 /* 46 * Symbol referenced by GCC compiler generated code for canary value. 47 * The canary value gets initialized in z_cstart(). 48 */ 49 #ifdef CONFIG_STACK_CANARIES_TLS 50 __thread uintptr_t __stack_chk_guard; 51 #elif CONFIG_USERSPACE 52 K_APP_DMEM(z_libc_partition) uintptr_t __stack_chk_guard; 53 #else 54 __noinit uintptr_t __stack_chk_guard; 55 #endif 56 57 /** 58 * 59 * @brief Referenced by GCC compiler generated code 60 * 61 * This routine is invoked when a stack canary error is detected, indicating 62 * a buffer overflow or stack corruption problem. 63 */ 64 FUNC_ALIAS(_StackCheckHandler, __stack_chk_fail, void); 65
