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Date:   Tue, 3 Oct 2023 16:44:09 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Justin Stitt <justinstitt@google.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2] x86/tdx: replace deprecated strncpy with strtomem_pad
Message-ID: <202310031642.E858E955B2@keescook>
References: <20231003-strncpy-arch-x86-coco-tdx-tdx-c-v2-1-0bd21174a217@google.com>
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In-Reply-To: <20231003-strncpy-arch-x86-coco-tdx-tdx-c-v2-1-0bd21174a217@google.com>
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On Tue, Oct 03, 2023 at 09:54:59PM +0000, Justin Stitt wrote:
> strncpy works perfectly here in all cases, however, it is deprecated and
> as such we should prefer more robust and less ambiguous string apis.
> 
> Let's use `strtomem_pad` as this matches the functionality of `strncpy`
> and is _not_ deprecated.
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
> Link: https://github.com/KSPP/linux/issues/90
> Cc: linux-hardening@vger.kernel.org
> Cc: Kees Cook <keescook@chromium.org>
> Signed-off-by: Justin Stitt <justinstitt@google.com>

Thanks for respinning this! And yeah, I'd agree the comment probably
should stay.

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

-- 
Kees Cook