Commit 113c5413 authored by Ingo Molnar's avatar Ingo Molnar Committed by Thomas Gleixner
Browse files

x86: unify stackprotector features 



streamline the stackprotector features under a single option
and make the stronger feature the one accessible.

Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 960a672b

arch/x86/Kconfig

+9 −13
Original line number Diff line number Diff line
@@ -1140,13 +1140,17 @@ config SECCOMP 


	  If unsure, say Y. Only embedded should say N here.



config CC_STACKPROTECTOR_ALL

	bool



config CC_STACKPROTECTOR

	bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"

	depends on X86_64

	select CC_STACKPROTECTOR_ALL

	help

          This option turns on the -fstack-protector GCC feature. This

	  feature puts, at the beginning of critical functions, a canary

	  value on the stack just before the return address, and validates

	  feature puts, at the beginning of functions, a canary value on

	  the stack just before the return address, and validates

	  the value just before actually returning.  Stack based buffer

	  overflows (that need to overwrite this return address) now also

	  overwrite the canary, which gets detected and the attack is then
@@ -1154,16 +1158,8 @@ config CC_STACKPROTECTOR 


	  This feature requires gcc version 4.2 or above, or a distribution

	  gcc with the feature backported. Older versions are automatically

	  detected and for those versions, this configuration option is ignored.



config CC_STACKPROTECTOR_ALL

	bool "Use stack-protector for all functions"

	depends on CC_STACKPROTECTOR

	default y

	help

	  Normally, GCC only inserts the canary value protection for

	  functions that use large-ish on-stack buffers. By enabling

	  this option, GCC will be asked to do this for ALL functions.

	  detected and for those versions, this configuration option is

	  ignored. (and a warning is printed during bootup)



source kernel/Kconfig.hz