x86: unify stackprotector features

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

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Ingo Molnar 2008-02-14 10:36:03 +01:00 committed by Thomas Gleixner
parent 960a672bd9
commit 113c5413cf

View file

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