Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18;
From:   Kees Cook <keescook@chromium.org>
To:     Richard Weinberger <richard@nod.at>,
        Anton Ivanov <anton.ivanov@cambridgegreys.com>,
        Johannes Berg <johannes@sipsolutions.net>,
        Justin Stitt <justinstitt@google.com>
Cc:     Kees Cook <keescook@chromium.org>, linux-um@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] um: vector: refactor deprecated strncpy
Date:   Wed, 16 Aug 2023 13:50:50 -0700
Message-Id: <169221904769.1235632.10910494392812070923.b4-ty@chromium.org>
In-Reply-To: <20230807-arch-um-drivers-v1-1-10d602c5577a@google.com>
References: <20230807-arch-um-drivers-v1-1-10d602c5577a@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8bit
Precedence: bulk

On Mon, 07 Aug 2023 18:22:30 +0000, Justin Stitt wrote:
> `strncpy` is deprecated for use on NUL-terminated destination strings [1].
> 
> A suitable replacement is `strscpy` [2] due to the fact that it
> guarantees NUL-termination on its destination buffer argument which is
> _not_ the case for `strncpy`!
> 
> In this case, we are able to drop the now superfluous `... - 1`
> instances because `strscpy` will automatically truncate the last byte by
> setting it to a NUL byte if the source size exceeds the destination size
> or if the source string is not NUL-terminated.
> 
> [...]

Applied to for-next/hardening, thanks!

[1/1] um: vector: refactor deprecated strncpy
      https://git.kernel.org/kees/c/30bed99e0c63

Take care,

-- 
Kees Cook