mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-21 18:14:48 +08:00
7f6240858c
Defer enabling pointer authentication on boot core until after its required to be enabled by cpufeature framework. This will help in controlling the feature dynamically with a boot parameter. Signed-off-by: Ajay Patil <pajay@qti.qualcomm.com> Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org> Signed-off-by: Srinivas Ramana <sramana@codeaurora.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/1610152163-16554-2-git-send-email-sramana@codeaurora.org Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: David Brazdil <dbrazdil@google.com> Link: https://lore.kernel.org/r/20210208095732.3267263-22-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
48 lines
1.3 KiB
C
48 lines
1.3 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 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 <linux/random.h>
|
|
#include <linux/version.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;
|
|
|
|
/* 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;
|
|
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 */
|