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Date:   Thu, 14 Sep 2023 22:18:05 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Justin Stitt <justinstitt@google.com>
Cc:     Ed Brindley <kernel@maidavale.org>,
        Denis Pauk <pauk.denis@gmail.com>,
        Jean Delvare <jdelvare@suse.com>,
        Guenter Roeck <linux@roeck-us.net>,
        linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH] hwmon: (asus_wmi_sensors) refactor deprecated strncpy
Message-ID: <202309142217.52EEAEA1@keescook>
References: <20230914-strncpy-drivers-hwmon-asus_wmi_sensors-c-v1-1-e1703cf91693@google.com>
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In-Reply-To: <20230914-strncpy-drivers-hwmon-asus_wmi_sensors-c-v1-1-e1703cf91693@google.com>
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On Thu, Sep 14, 2023 at 11:10:34PM +0000, Justin Stitt wrote:
> `strncpy` is deprecated for use on NUL-terminated destination strings [1].
> 
> We should prefer more robust and less ambiguous string interfaces.
> 
> A suitable replacement is `strscpy` [2] due to the fact that it
> guarantees NUL-termination on the destination buffer without
> unnecessarily NUL-padding. If, for any reason, NUL-padding is needed
> let's opt for `strscpy_pad`.
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
> Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
> Link: https://github.com/KSPP/linux/issues/90
> Cc: linux-hardening@vger.kernel.org
> Signed-off-by: Justin Stitt <justinstitt@google.com>

A classic replacement. :)

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook