Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Kees Cook <keescook@chromium.org>
To:     andy@kernel.org, Andrew Morton <akpm@linux-foundation.org>,
        glider@google.com
Cc:     Kees Cook <keescook@chromium.org>, nathan@kernel.org,
        dvyukov@google.com, elver@google.com, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, kasan-dev@googlegroups.com,
        ndesaulniers@google.com
Subject: Re: [PATCH v2] string: use __builtin_memcpy() in strlcpy/strlcat
Date:   Tue, 30 May 2023 16:10:46 -0700
Message-Id: <168548824525.1351231.6995242566921339574.b4-ty@chromium.org>
In-Reply-To: <20230530083911.1104336-1-glider@google.com>
References: <20230530083911.1104336-1-glider@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8bit
Precedence: bulk

On Tue, 30 May 2023 10:39:11 +0200, Alexander Potapenko wrote:
> lib/string.c is built with -ffreestanding, which prevents the compiler
> from replacing certain functions with calls to their library versions.
> 
> On the other hand, this also prevents Clang and GCC from instrumenting
> calls to memcpy() when building with KASAN, KCSAN or KMSAN:
>  - KASAN normally replaces memcpy() with __asan_memcpy() with the
>    additional cc-param,asan-kernel-mem-intrinsic-prefix=1;
>  - KCSAN and KMSAN replace memcpy() with __tsan_memcpy() and
>    __msan_memcpy() by default.
> 
> [...]

Applied to for-next/hardening, thanks!

[1/1] string: use __builtin_memcpy() in strlcpy/strlcat
      https://git.kernel.org/kees/c/cfe93c8c9a7a

-- 
Kees Cook