diff options
author | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2010-08-16 18:42:58 +0100 |
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committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2010-08-16 18:42:58 +0100 |
commit | e4862f2f6f5653dfb67f3ba2b6f0bc74516ed51a (patch) | |
tree | 1db5a0540a4eecfad9b7daee476b985e82ddc810 /arch/arm/include/asm/stackprotector.h | |
parent | ec62dbd7eb8e3dddb221da89ecbcea0fc3dee8c1 (diff) | |
parent | b2c1e07b81a126e5846dfc3d36f559d861df59f4 (diff) |
Merge branch 'for-2.6.36' into for-2.6.37
Fairly simple conflicts, the most serious ones are the i.MX ones which I
suspect now need another rename.
Conflicts:
arch/arm/mach-mx2/clock_imx27.c
arch/arm/mach-mx2/devices.c
arch/arm/mach-omap2/board-rx51-peripherals.c
arch/arm/mach-omap2/board-zoom2.c
sound/soc/fsl/mpc5200_dma.c
sound/soc/fsl/mpc5200_dma.h
sound/soc/fsl/mpc8610_hpcd.c
sound/soc/pxa/spitz.c
Diffstat (limited to 'arch/arm/include/asm/stackprotector.h')
-rw-r--r-- | arch/arm/include/asm/stackprotector.h | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/arch/arm/include/asm/stackprotector.h b/arch/arm/include/asm/stackprotector.h new file mode 100644 index 00000000000..de003327be9 --- /dev/null +++ b/arch/arm/include/asm/stackprotector.h @@ -0,0 +1,38 @@ +/* + * 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 1 + +#include <linux/random.h> +#include <linux/version.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) +{ + unsigned long canary; + + /* Try to get a semi random initial value. */ + get_random_bytes(&canary, sizeof(canary)); + canary ^= LINUX_VERSION_CODE; + + current->stack_canary = canary; + __stack_chk_guard = current->stack_canary; +} + +#endif /* _ASM_STACKPROTECTOR_H */ |