Re: more build problems with "Makefile: move stackprotector availability out of Kconfig"

[Kees Cook]

On Wed, Oct 18, 2017 at 5:41 PM, Masahiro Yamada
<yamada.masahiro@xxxxxxxxxxxxx> wrote:
> Hi Kees,
>
> 2017-10-18 5:06 GMT+09:00 Kees Cook <keescook@xxxxxxxxxxxx>:
>> On Tue, Oct 17, 2017 at 12:56 PM, Andrew Morton
>> <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
>>> On Tue, 17 Oct 2017 11:53:10 -0700 Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>>>
>>>> On Tue, Oct 17, 2017 at 11:52 AM, Mark Brown <broonie@xxxxxxxxxx> wrote:
>>>> > On Tue, Oct 17, 2017 at 08:47:06PM +0200, Arnd Bergmann wrote:
>>>> >
>>>> >> To clarify: with my gcc-4.9/gcc-5 build, -mstack-protector-guard=tls
>>>> >> has no effect,
>>>> >> the output is the same as with -mstack-protector-guard=global using the Ubuntu
>>>> >> compilers of the same version.
>>>> >
>>>> > Jumping in here...  on IRC Arnd suggested reverting 123c48cf899d
>>>> > ("Makefile: introduce CONFIG_CC_STACKPROTECTOR_AUTO") from -next.  What
>>>> > do you think Kees?
>>>>
>>>> Until we sort this out, yes, agreed. Andrew, can you pull the patches?
>>>
>>> Sure.  All these?
>>>
>>> sh-boot-add-static-stack-protector-to-pre-kernel.patch
>>> makefile-move-stackprotector-availability-out-of-kconfig.patch
>>
>> This one can stay. (It does actually fix another case no one else noticed.)
>>
>>> makefile-introduce-config_cc_stackprotector_auto.patch
>>> makefile-introduce-config_cc_stackprotector_auto-fix.patch
>>> makefile-introduce-config_cc_stackprotector_auto-fix-2.patch
>>> makefile-introduce-config_cc_stackprotector_auto-fix-3.patch
>>
>> Yes, these should get dropped for the moment, thanks. Arnd and I have
>> been trying to get to the bottom of it.
>>
>> -Kees
>
>
> I see this series is repeating apply/drop,
> so I am not tracking down the latest status.

They're currently dropped from -next while I figure out what's
breaking 0-day (I haven't had a chance to track it down yet).

> When you have a chance for re-spin,
> please replace
>
>    KBUILD_CFLAGS += -DCONFIG_CC_STACKPROTECTOR
>    KBUILD_AFLAGS += -DCONFIG_CC_STACKPROTECTOR
>
> with
>
>    KBUILD_CPPFLAGS += -DCONFIG_CC_STACKPROTECTOR

Ah! Sure. For some reason I thought CPPFLAGS weren't include in .S builds.

-Kees

-- 
Kees Cook
Pixel Security