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Date:   Tue, 3 Oct 2023 16:46:49 -0700
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Subject: Re: [PATCH v2] x86/tdx: replace deprecated strncpy with strtomem_pad
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To:     Justin Stitt <justinstitt@google.com>,
        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>
Cc:     linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org,
        Kees Cook <keescook@chromium.org>
References: <20231003-strncpy-arch-x86-coco-tdx-tdx-c-v2-1-0bd21174a217@google.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20231003-strncpy-arch-x86-coco-tdx-tdx-c-v2-1-0bd21174a217@google.com>
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On 10/3/23 14:54, Justin Stitt wrote:
> Note: Ingo Molnar has some concerns about the comment being out of sync
> [1] but I believe the comment still has a place as we can still
> theoretically copy 64 bytes into our destination buffer without a
> NUL-byte. The extra information about the 65th byte being NUL may serve
> helpful to future travelers of this code. What do we think? I can drop
> the comment in a v3 if needed.

The comment looks fine to me as you've left it.  It _might_ be better to
say something like:

	Empty space in 'message.str' needs to be overwritten
	but does not need to be NULL-terminated.

But I wouldn't bother messing with it any more.

Acked-by: Dave Hansen <dave.hansen@linux.intel.com>

I'll stick this into the tdx branch tomorrow unless someone has stronger
feelings about it.