linux/arch/loongarch/include/asm/stackprotector.h
Huacai Chen 09f33601bf LoongArch: Add basic STACKPROTECTOR support
Add basic stack protector support similar to other architectures. A
constant canary value is set at boot time, and with help of compiler's
-fstack-protector we can detect stack corruption.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-12-14 08:41:53 +08:00

38 lines
1 KiB
C

/* 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
* on LoongArch gcc expects it to be defined by a global variable called
* "__stack_chk_guard".
*/
#ifndef _ASM_STACKPROTECTOR_H
#define _ASM_STACKPROTECTOR_H
#include <linux/random.h>
#include <linux/version.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)
{
unsigned long canary;
/* Try to get a semi random initial value. */
get_random_bytes(&canary, sizeof(canary));
canary ^= LINUX_VERSION_CODE;
current->stack_canary = canary;
__stack_chk_guard = current->stack_canary;
}
#endif /* _ASM_STACKPROTECTOR_H */