linux/arch/csky/include/asm/stackprotector.h
Mao Han 2f78c73f78 csky: Initial stack protector support
This is a basic -fstack-protector support without per-task canary
switching. The protector will report something like when stack
corruption is detected:

It's tested with strcpy local array overflow in sys_kill and get:
stack-protector: Kernel stack is corrupted in: sys_kill+0x23c/0x23c

TODO:
 - Support task switch for different cannary

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2020-02-21 15:43:24 +08:00

30 lines
705 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_STACKPROTECTOR_H
#define _ASM_STACKPROTECTOR_H 1
#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;
canary &= CANARY_MASK;
current->stack_canary = canary;
__stack_chk_guard = current->stack_canary;
}
#endif /* __ASM_SH_STACKPROTECTOR_H */