From: Arjan van de Ven This patch adds the config options for -fstack-protector. Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Cc: Andi Kleen Signed-off-by: Andrew Morton --- arch/x86_64/Kconfig | 24 ++++++++++++++++++++++++ 1 files changed, 24 insertions(+) diff -puN arch/x86_64/Kconfig~fstack-protector-feature-add-the-kconfig-option arch/x86_64/Kconfig --- a/arch/x86_64/Kconfig~fstack-protector-feature-add-the-kconfig-option +++ a/arch/x86_64/Kconfig @@ -529,6 +529,30 @@ config SECCOMP If unsure, say Y. Only embedded should say N here. +config CC_STACKPROTECTOR + bool "Enable -fstack-protector buffer overflow detection (EXPRIMENTAL)" + depends on EXPERIMENTAL + 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 + 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 + neutralized via a kernel panic. + + 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 + 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. + source kernel/Kconfig.hz config REORDER _