Merge branch 'core-stackprotector-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull strong stackprotector support from Ingo Molnar:
 "This tree adds a CONFIG_CC_STACKPROTECTOR_STRONG=y, a new, stronger
  stack canary checking method supported by the newest GCC versions (4.9
  and later).

  Here's the 'intensity comparison' between the various protection
  modes:

      - defconfig
        11430641 kernel text size
        36110 function bodies

      - defconfig + CONFIG_CC_STACKPROTECTOR_REGULAR
        11468490 kernel text size (+0.33%)
        1015 of 36110 functions are stack-protected (2.81%)

      - defconfig + CONFIG_CC_STACKPROTECTOR_STRONG via this patch
        11692790 kernel text size (+2.24%)
        7401 of 36110 functions are stack-protected (20.5%)

  the strong model comes with non-trivial costs, which is why we
  preserved the 'regular' and 'none' models as well"

* 'core-stackprotector-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  stackprotector: Introduce CONFIG_CC_STACKPROTECTOR_STRONG
  stackprotector: Unify the HAVE_CC_STACKPROTECTOR logic between architectures

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)