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Date:   Fri, 15 Sep 2023 12:53:20 -0700
From:   Kees Cook <keescook@chromium.org>
To:     "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc:     Ishizaki Kou <kou.ishizaki@toshiba.co.jp>,
        Geoff Levand <geoff@infradead.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
        netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH][next] net: spider_net: Use size_add() in call to
 struct_size()
Message-ID: <202309151253.844C8BFCA3@keescook>
References: <ZQSvsLmJrDsKtLCa@work>
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On Fri, Sep 15, 2023 at 01:25:36PM -0600, Gustavo A. R. Silva wrote:
> If, for any reason, the open-coded arithmetic causes a wraparound,
> the protection that `struct_size()` adds against potential integer
> overflows is defeated. Fix this by hardening call to `struct_size()`
> with `size_add()`.
> 
> Fixes: 3f1071ec39f7 ("net: spider_net: Use struct_size() helper")
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

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

-- 
Kees Cook