toolchain/buildroot: properly handle SSP

The current SSP handling is incomplete.

First we need to build uClibc with SSP support for a complete
"experience".

Second, it doesn't hurt to add -fstack-protector-all to the
CFLAGS/CXXFLAGS since most users would expect buildroot to do this
rather than adding the flags themselves.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/Makefile.in

@@ -124,6 +124,11 @@ TARGET_CFLAGS += -msep-data
 TARGET_CXXFLAGS += -msep-data
 endif
 
+ifeq ($(BR2_TOOLCHAIN_BUILDROOT_USE_SSP),y)
+TARGET_CFLAGS += -fstack-protector-all
+TARGET_CXXFLAGS += -fstack-protector-all
+endif
+
 ifeq ($(BR2_TOOLCHAIN_BUILDROOT)$(BR2_TOOLCHAIN_CTNG),y)
 TARGET_CROSS=$(HOST_DIR)/usr/bin/$(GNU_TARGET_NAME)-
 else

package/uclibc/uclibc.mk

@@ -251,9 +251,15 @@ endif
 # SSP
 #
 ifeq ($(BR2_TOOLCHAIN_BUILDROOT_USE_SSP),y)
-UCLIBC_SSP_CONFIG = $(call UCLIBC_OPT_SET,UCLIBC_HAS_SSP,y,$(@D))
+define UCLIBC_SSP_CONFIG
+	$(call UCLIBC_OPT_SET,UCLIBC_HAS_SSP,y,$(@D))
+	$(call UCLIBC_OPT_SET,UCLIBC_BUILD_SSP,y,$(@D))
+endef
 else
-UCLIBC_SSP_CONFIG = $(call UCLIBC_OPT_UNSET,UCLIBC_HAS_SSP,$(@D))
+define UCLIBC_SSP_CONFIG
+	$(call UCLIBC_OPT_UNSET,UCLIBC_HAS_SSP,$(@D))
+	$(call UCLIBC_OPT_UNSET,UCLIBC_BUILD_SSP,$(@D))
+endef
 endif
 
 #

toolchain/toolchain-buildroot/Config.in.2

@@ -21,7 +21,7 @@ config BR2_TOOLCHAIN_BUILDROOT_USE_SSP
 	bool "Enable stack protection support"
 	help
 	  Enable stack smashing protection support using GCCs
-	  -fstack-protector[-all] option.
+	  -fstack-protector-all option.
 
 	  See http://www.linuxfromscratch.org/hints/downloads/files/ssp.txt
 	  for details.