stackprotector: Unify the HAVE_CC_STACKPROTECTOR logic between architectures

Instead of duplicating the CC_STACKPROTECTOR Kconfig and
Makefile logic in each architecture, switch to using
HAVE_CC_STACKPROTECTOR and keep everything in one place. This
retains the x86-specific bug verification scripts.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@linux-mips.org
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/1387481759-14535-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 1 insertions, 18 deletions

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 9b0979f4df7a..ce298317a73e 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -66,6 +66,7 @@ config SUPERH32
         select PERF_EVENTS
         select ARCH_HIBERNATION_POSSIBLE if MMU
         select SPARSE_IRQ
+        select HAVE_CC_STACKPROTECTOR
 
 config SUPERH64
         def_bool ARCH = "sh64"
@@ -695,20 +696,6 @@ config SECCOMP
 
           If unsure, say N.
 
-config CC_STACKPROTECTOR
-        bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
-        depends on SUPERH32
-        help
-          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
-          neutralized via a kernel panic.
-
-          This feature requires gcc version 4.2 or above.
-
 config SMP
         bool "Symmetric multi-processing support"
         depends on SYS_SUPPORTS_SMP
diff --git a/arch/sh/Makefile b/arch/sh/Makefile
index aed701c7b11b..d4d16e4be07c 100644
--- a/arch/sh/Makefile
+++ b/arch/sh/Makefile
@@ -199,10 +199,6 @@ ifeq ($(CONFIG_DWARF_UNWINDER),y)
   KBUILD_CFLAGS += -fasynchronous-unwind-tables
 endif
 
-ifeq ($(CONFIG_CC_STACKPROTECTOR),y)
-  KBUILD_CFLAGS += -fstack-protector
-endif
-
 libs-$(CONFIG_SUPERH32)         := arch/sh/lib/ $(libs-y)
 libs-$(CONFIG_SUPERH64)         := arch/sh/lib64/ $(libs-y)