Re: [PATCH] lkdtm: Fix targets for objcopy usage

From: Mark Rutland
Date: Fri Jul 29 2016 - 05:38:15 EST


Hi,

On Thu, Jul 28, 2016 at 07:30:39PM -0700, Kees Cook wrote:
> The targets for lkdtm's objcopy were missing which caused them to always
> be rebuilt. This corrects the problem.
>
> Additionally, commit f8fa70f392fa ("arm64: localise Image objcopy flags")
> has landed now, so this removes the work-around for the global OBJCOPY
> flag setting.
>
> Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

With this applied, LKDTM builds fine for me on arm64, the redundant
rebuilds are gone, and the result appears to work. So FWIW:

Tested-by: Mark Rutland <mark.rutland@xxxxxxx>

Thanks,
Mark.

> ---
> drivers/misc/Makefile | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
> index 4387ccb79e64..132f4e3462ba 100644
> --- a/drivers/misc/Makefile
> +++ b/drivers/misc/Makefile
> @@ -65,9 +65,9 @@ lkdtm-$(CONFIG_LKDTM) += lkdtm_perms.o
> lkdtm-$(CONFIG_LKDTM) += lkdtm_rodata_objcopy.o
> lkdtm-$(CONFIG_LKDTM) += lkdtm_usercopy.o
>
> -OBJCOPYFLAGS :=
> OBJCOPYFLAGS_lkdtm_rodata_objcopy.o := \
> --set-section-flags .text=alloc,readonly \
> --rename-section .text=.rodata
> -$(obj)/lkdtm_rodata_objcopy.o: $(obj)/lkdtm_rodata.o
> +targets += lkdtm_rodata.o lkdtm_rodata_objcopy.o
> +$(obj)/lkdtm_rodata_objcopy.o: $(obj)/lkdtm_rodata.o FORCE
> $(call if_changed,objcopy)
> --
> 2.7.4
>
>
> --
> Kees Cook
> Brillo & Chrome OS Security
>