arm-trusted-firmware/lib/stack_protector/aarch32/asm_stack_protector.S
dp-arm 82cb2c1ad9 Use SPDX license identifiers
To make software license auditing simpler, use SPDX[0] license
identifiers instead of duplicating the license text in every file.

NOTE: Files that have been imported by FreeBSD have not been modified.

[0]: https://spdx.org/

Change-Id: I80a00e1f641b8cc075ca5a95b10607ed9ed8761a
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
2017-05-03 09:39:28 +01:00

34 lines
949 B
ArmAsm

/*
* Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch.h>
#include <asm_macros.S>
#include <assert_macros.S>
.globl update_stack_protector_canary
/* -----------------------------------------------------------------------
* void update_stack_protector_canary(void)
*
* Change the value of the canary used for stack smashing attacks protection.
* Note: This must be called when it is safe to call C code, but this cannot be
* called by C code. Doing this will make the check fail when the calling
* function returns.
* -----------------------------------------------------------------------
*/
func update_stack_protector_canary
/* Use r4 as it is callee-saved */
mov r4, lr
bl plat_get_stack_protector_canary
/* Update the canary with the returned value */
ldr r1, =__stack_chk_guard
str r0, [r1]
bx r4
endfunc update_stack_protector_canary