Re: [PATCH mptcp-next RFC 2/3] mptcp: reject MP_JOIN earlier
Paolo Abeni <[email protected]>
| Newsgroups | dev.linux.lists.mptcp |
|---|---|
| Message-ID | <[email protected]> |
On 8/14/26 8:31 PM, Matthieu Baerts (NGI0) wrote:
> @@ -91,12 +92,22 @@ static struct mptcp_sock *subflow_token_join_request(struct request_sock *req)
> msk = mptcp_token_get_sock(sock_net(req_to_sk(req)), subflow_req->token);
> if (!msk) {
> SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINNOTOKEN);
> + *reason = MPTCP_RST_EMPTCP;
> + return NULL;
> + }
> +
> + /* Stop it early if the subflow cannot be accepted */
> + if (!mptcp_can_accept_new_subflow(msk)) {
Side note: the above is inherently racy, the consistency safeguard is
given by the fallback check at finish_join time.
Minor nit: I'm not sure this check belongs here or in
subflow_check_req(). The latter option would avoid the additional
argument and possibly produce a smaller diff (and smaller code).
/P