Re: [PATCH 2/6] efi: Avoid fortify checks in EFI stub

From: Ard Biesheuvel
Date: Tue Jun 06 2017 - 13:13:12 EST


(+ Mark, Matt)

On 6 June 2017 at 04:52, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> This avoids CONFIG_FORTIFY_SOURCE from being enabled during the EFI stub
> build, as adding a panic() implementation may not work well. This can be
> adjusted in the future.
>
> Suggested-by: Daniel Micay <danielmicay@xxxxxxxxx>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc; Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
> ---
> drivers/firmware/efi/libstub/Makefile | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
> index f7425960f6a5..37e24f525162 100644
> --- a/drivers/firmware/efi/libstub/Makefile
> +++ b/drivers/firmware/efi/libstub/Makefile
> @@ -17,6 +17,7 @@ cflags-$(CONFIG_ARM) := $(subst -pg,,$(KBUILD_CFLAGS)) \
> cflags-$(CONFIG_EFI_ARMSTUB) += -I$(srctree)/scripts/dtc/libfdt
>
> KBUILD_CFLAGS := $(cflags-y) -DDISABLE_BRANCH_PROFILING \
> + -D__NO_FORTIFY \
> $(call cc-option,-ffreestanding) \
> $(call cc-option,-fno-stack-protector)
>

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

This is unlikely to conflict with anything going through the EFI tree,
so feel free to queue it elsewhere.