Subject: Re: [PATCH 4/4] kasan: add compiler support for clang
To: Greg Hackmann <ghackmann@google.com>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Michal Marek <mmarek@suse.com>
Cc: linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com,
        linux-mm@kvack.org, linux-kbuild@vger.kernel.org,
        Matthias Kaehlcke <mka@chromium.org>, Michael Davidson <md@google.com>
References: <20170706220114.142438-1-ghackmann@google.com>
 <20170706220114.142438-5-ghackmann@google.com>
From: Andrey Ryabinin <aryabinin@virtuozzo.com>
Message-ID: <34230d2e-c134-6cbc-2a59-c78c78782526@virtuozzo.com>
Date: Mon, 10 Jul 2017 13:34:24 +0300
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On 07/07/2017 01:01 AM, Greg Hackmann wrote:
> For now we can hard-code ASAN ABI level 5, since historical clang builds
> can't build the kernel anyway.  We also need to emulate gcc's
> __SANITIZE_ADDRESS__ flag, or memset() calls won't be instrumented.
> 
> Signed-off-by: Greg Hackmann <ghackmann@google.com>
> ---
>  include/linux/compiler-clang.h | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h
> index d614c5ea1b5e..8153f793b22a 100644
> --- a/include/linux/compiler-clang.h
> +++ b/include/linux/compiler-clang.h
> @@ -23,3 +23,13 @@
>   */
>  #undef inline
>  #define inline inline __attribute__((unused)) notrace
> +
> +/* all clang versions usable with the kernel support KASAN ABI version 5
> + */

 Enclosing */ should be on the same line for single-line comments.

> +#define KASAN_ABI_VERSION 5
> +
> +/* emulate gcc's __SANITIZE_ADDRESS__ flag
> + */

Ditto.

> +#if __has_feature(address_sanitizer)
> +#define __SANITIZE_ADDRESS__
> +#endif
>