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Date:   Wed, 9 Aug 2023 22:20:54 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Justin Stitt <justinstitt@google.com>
Cc:     Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        Florian Westphal <fw@strlen.de>,
        "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 7/7] netfilter: xtables: refactor deprecated strncpy
Message-ID: <20230809202054.GC3325@breakpoint.cc>
References: <20230809-net-netfilter-v2-0-5847d707ec0a@google.com>
 <20230809-net-netfilter-v2-7-5847d707ec0a@google.com>
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Justin Stitt <justinstitt@google.com> wrote:
> Prefer `strscpy_pad` as it's a more robust interface whilst maintaing
> zero-padding behavior.
> 
> There may have existed a bug here due to both `tbl->repl.name` and
> `info->name` having a size of 32 as defined below:
> |  #define XT_TABLE_MAXNAMELEN 32
> 
> This may lead to buffer overreads in some situations -- `strscpy` solves
> this by guaranteeing NUL-termination of the dest buffer.

I don't think we need to use _pad here.