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

[Eric Dumazet]

On Mon, Dec 9, 2024 at 1:28 PM Matthieu Baerts (NGI0)
<matttbe@xxxxxxxxxx> wrote:
>
> From: MoYuanhao <moyuanhao3676@xxxxxxx>
>
> 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@xxxxxxx>
> Fixes: cec37a6e41aa ("mptcp: Handle MP_CAPABLE options for outgoing connections")
> Cc: stable@xxxxxxxxxxxxxxx
> Acked-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
> [ Matt: Add Fixes, cc Stable, update Description ]
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>

Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>