RE: [PATCH] kasan: Add CONFIG_KASAN_WHITELIST_ONLY mode

[Joey Jiao (QUIC)]

Right, it will be only useful for low memory kernel where 'KASAN_SANITIZE :=y' has to be added explicitly in local as hotfix.

-----Original Message-----
From: Masahiro Yamada <masahiroy@xxxxxxxxxx> 
Sent: Saturday, September 30, 2023 6:12 PM
To: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Joey Jiao (QUIC) <quic_jiangenj@xxxxxxxxxxx>; kasan-dev@xxxxxxxxxxxxxxxx; Kevin Ding (QUIC) <quic_likaid@xxxxxxxxxxx>; Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>; Andrey Konovalov <andreyknvl@xxxxxxxxx>; Dmitry Vyukov <dvyukov@xxxxxxxxxx>; Vincenzo Frascino <vincenzo.frascino@xxxxxxx>; Nathan Chancellor <nathan@xxxxxxxxxx>; Nick Desaulniers <ndesaulniers@xxxxxxxxxx>; Nicolas Schier <nicolas@xxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; linux-kbuild@xxxxxxxxxxxxxxx
Subject: Re: [PATCH] kasan: Add CONFIG_KASAN_WHITELIST_ONLY mode

On Fri, Sep 29, 2023 at 11:06 PM Alexander Potapenko <glider@xxxxxxxxxx> wrote:
>
> (CC Masahiro Yamada)
>
> On Thu, Sep 28, 2023 at 6:16 AM Joey Jiao <quic_jiangenj@xxxxxxxxxxx> wrote:
> >
> > Fow low memory device, full enabled kasan just not work.
> > Set KASAN_SANITIZE to n when CONFIG_KASAN_WHITELIST_ONLY=y.
> > So we can enable kasan for single file or module.
>
> I don't have technical objections here, but it bothers me a bit that 
> we are adding support for KASAN_SANITIZE:=y, although nobody will be 
> adding KASAN_SANITIZE:=y to upstream Makefiles - only development 
> kernels when debugging on low-end devices.
>
> Masahiro, is this something worth having in upstream Kconfig code?


Even if we apply this patch to the upstream, you will end up with adding 'KASAN_SANITIZE :=y'
to the single file/Makefile.

I am not convinced with this patch
since this nod is not so useful standalone.



> > Signed-off-by: Joey Jiao <quic_jiangenj@xxxxxxxxxxx>
> Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx>



--
Best Regards
Masahiro Yamada