mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-03 17:40:04 +00:00
![Christophe Leroy](/assets/img/avatar_default.png)
On PPC64, as register r13 points to the paca_struct at all time, this patch adds a copy of the canary there, which is copied at task_switch. That new canary is then used by using the following GCC options: -mstack-protector-guard=tls -mstack-protector-guard-reg=r13 -mstack-protector-guard-offset=offsetof(struct paca_struct, canary)) Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
38 lines
788 B
C
38 lines
788 B
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* GCC stack protector support.
|
|
*
|
|
*/
|
|
|
|
#ifndef _ASM_STACKPROTECTOR_H
|
|
#define _ASM_STACKPROTECTOR_H
|
|
|
|
#include <linux/random.h>
|
|
#include <linux/version.h>
|
|
#include <asm/reg.h>
|
|
#include <asm/current.h>
|
|
#include <asm/paca.h>
|
|
|
|
/*
|
|
* 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. */
|
|
canary = get_random_canary();
|
|
canary ^= mftb();
|
|
canary ^= LINUX_VERSION_CODE;
|
|
canary &= CANARY_MASK;
|
|
|
|
current->stack_canary = canary;
|
|
#ifdef CONFIG_PPC64
|
|
get_paca()->canary = canary;
|
|
#endif
|
|
}
|
|
|
|
#endif /* _ASM_STACKPROTECTOR_H */
|