diff options
Diffstat (limited to 'include/asm-x86/stackprotector.h')
| -rw-r--r-- | include/asm-x86/stackprotector.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/include/asm-x86/stackprotector.h b/include/asm-x86/stackprotector.h index dcac7a6bdba..0f91f7a2688 100644 --- a/include/asm-x86/stackprotector.h +++ b/include/asm-x86/stackprotector.h @@ -1,4 +1,24 @@ #ifndef _ASM_STACKPROTECTOR_H #define _ASM_STACKPROTECTOR_H 1 +/* + * 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 we're the non-boot CPU, nothing set the PDA stack + * canary up for us - and if we are the boot CPU we have + * a 0 stack canary. This is a good place for updating + * it, as we wont ever return from this function (so the + * invalid canaries already on the stack wont ever + * trigger): + */ + current->stack_canary = get_random_int(); + write_pda(stack_canary, current->stack_canary); +} + #endif |