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Date:   Wed, 9 Aug 2023 23:54:48 +0200 (CEST)
From:   Jan Engelhardt <jengelh@inai.de>
To:     Justin Stitt <justinstitt@google.com>
cc:     Florian Westphal <fw@strlen.de>,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        linux-hardening@vger.kernel.org, Kees Cook <keescook@chromium.org>,
        netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/7] netfilter: ipset: refactor deprecated strncpy
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On Wednesday 2023-08-09 23:40, Justin Stitt wrote:
>On Wed, Aug 9, 2023 at 1:19 PM Florian Westphal <fw@strlen.de> wrote:
>>
>> Justin Stitt <justinstitt@google.com> wrote:
>> > Use `strscpy_pad` instead of `strncpy`.
>>
>> I don't think that any of these need zero-padding.
>It's a more consistent change with the rest of the series and I don't
>believe it has much different behavior to `strncpy` (other than
>NUL-termination) as that will continue to pad to `n` as well.
>
>Do you think the `_pad` for 1/7, 6/7 and 7/7 should be changed back to
>`strscpy` in a v3? I really am shooting in the dark as it is quite
>hard to tell whether or not a buffer is expected to be NUL-padded or
>not.

I don't recall either NF userspace or kernelspace code doing memcmp
with name-like fields, so padding should not be strictly needed.