Re: [PATCH net] tcp: check space before adding MPTCP SYN options

On Mon, Dec 9, 2024 at 1:28 PM Matthieu Baerts (NGI0) matttbe@kernel.org wrote:

From: MoYuanhao moyuanhao3676@163.com

Ensure there is enough space before adding MPTCP options in tcp_syn_options().

Without this check, 'remaining' could underflow, and causes issues. If there is not enough space, MPTCP should not be used.

Signed-off-by: MoYuanhao moyuanhao3676@163.com Fixes: cec37a6e41aa ("mptcp: Handle MP_CAPABLE options for outgoing connections") Cc: stable@vger.kernel.org Acked-by: Matthieu Baerts (NGI0) matttbe@kernel.org [ Matt: Add Fixes, cc Stable, update Description ] Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org

Reviewed-by: Eric Dumazet edumazet@google.com