[PATCH v11 12/12] efi/libstub: disable SCS

[Sami Tolvanen]

Shadow stacks are not available in the EFI stub, filter out SCS flags.

Suggested-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
 drivers/firmware/efi/libstub/Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 094eabdecfe6..b52ae8c29560 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -32,6 +32,9 @@ KBUILD_CFLAGS			:= $(cflags-y) -DDISABLE_BRANCH_PROFILING \
 				   $(call cc-option,-fno-stack-protector) \
 				   -D__DISABLE_EXPORTS
 
+# remove SCS flags from all objects in this directory
+KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
+
 GCOV_PROFILE			:= n
 KASAN_SANITIZE			:= n
 UBSAN_SANITIZE			:= n
-- 
2.26.1.301.g55bc3eb7cb9-goog