diff options
Diffstat (limited to 'arch/x86/include/asm/stackprotector.h')
| -rw-r--r-- | arch/x86/include/asm/stackprotector.h | 17 |
1 files changed, 8 insertions, 9 deletions
diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h index c7f0d10bae7..36a700acaf2 100644 --- a/arch/x86/include/asm/stackprotector.h +++ b/arch/x86/include/asm/stackprotector.h @@ -2,7 +2,7 @@ #define _ASM_STACKPROTECTOR_H 1 #include <asm/tsc.h> -#include <asm/pda.h> +#include <asm/processor.h> /* * Initialize the stackprotector canary value. @@ -16,13 +16,12 @@ static __always_inline void boot_init_stack_canary(void) u64 tsc; /* - * 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). - * + * Build time only check to make sure the stack_canary is at + * offset 40 in the pda; this is a gcc ABI requirement + */ + BUILD_BUG_ON(offsetof(union irq_stack_union, stack_canary) != 40); + + /* * We both use the random pool and the current TSC as a source * of randomness. The TSC only matters for very early init, * there it already has some randomness on most systems. Later @@ -33,7 +32,7 @@ static __always_inline void boot_init_stack_canary(void) canary += tsc + (tsc << 32UL); current->stack_canary = canary; - write_pda(stack_canary, canary); + percpu_write(irq_stack_union.stack_canary, canary); } #endif |