/* SPDX-License-Identifier: GPL-2.0 *//* * GCC stack protector support. * * Stack protector works by putting predefined pattern at the start of * the stack frame and verifying that it hasn't been overwritten when * returning from the function.  The pattern is called stack canary * and gcc expects it to be defined by a global variable called * "__stack_chk_guard" on ARM.  This unfortunately means that on SMP * we cannot have a different canary value per task. */ #ifndef __ASM_STACKPROTECTOR_H#define __ASM_STACKPROTECTOR_H #include <asm/pointer_auth.h> extern unsigned long __stack_chk_guard; /* * Initialize the stackprotector canary value. * * NOTE: this must only be called from functions that never return, * and it must always be inlined. */static __always_inline void boot_init_stack_canary(void){#if defined(CONFIG_STACKPROTECTOR)	unsigned long canary = get_random_canary(); 	current->stack_canary = canary;	if (!IS_ENABLED(CONFIG_STACKPROTECTOR_PER_TASK))		__stack_chk_guard = current->stack_canary;#endif	ptrauth_thread_init_kernel(current);	ptrauth_thread_switch_kernel(current);	ptrauth_enable();} #endif	/* _ASM_STACKPROTECTOR_H */