Commit 724b00c1 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

mptcp: refine opt_mp_capable determination 



OPTIONS_MPTCP_MPC is a combination of three flags.

It would be better to be strict about testing what
flag is expected, at least for code readability.

mptcp_parse_option() already makes the distinction.

- subflow_check_req() should use OPTION_MPTCP_MPC_SYN.

- mptcp_subflow_init_cookie_req() should use OPTION_MPTCP_MPC_ACK.

- subflow_finish_connect() should use OPTION_MPTCP_MPC_SYNACK

- subflow_syn_recv_sock should use OPTION_MPTCP_MPC_ACK

Suggested-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Acked-by: default avatarPaolo Abeni <pabeni@redhat.com>
Reviewed-by: default avatarMat Martineau <martineau@kernel.org>
Fixes: 74c7dfbe ("mptcp: consolidate in_opt sub-options fields in a bitmask")
Link: https://lore.kernel.org/r/20240111194917.4044654-6-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 66ff70df

net/mptcp/subflow.c

+4 −4
Original line number Diff line number Diff line
@@ -157,7 +157,7 @@ static int subflow_check_req(struct request_sock *req, 


	mptcp_get_options(skb, &mp_opt);



	opt_mp_capable = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPC);

	opt_mp_capable = !!(mp_opt.suboptions & OPTION_MPTCP_MPC_SYN);

	opt_mp_join = !!(mp_opt.suboptions & OPTION_MPTCP_MPJ_SYN);

	if (opt_mp_capable) {

		SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVE);
@@ -254,7 +254,7 @@ int mptcp_subflow_init_cookie_req(struct request_sock *req, 
	subflow_init_req(req, sk_listener);

	mptcp_get_options(skb, &mp_opt);



	opt_mp_capable = !!(mp_opt.suboptions & OPTIONS_MPTCP_MPC);

	opt_mp_capable = !!(mp_opt.suboptions & OPTION_MPTCP_MPC_ACK);

	opt_mp_join = !!(mp_opt.suboptions & OPTION_MPTCP_MPJ_ACK);

	if (opt_mp_capable && opt_mp_join)

		return -EINVAL;
@@ -486,7 +486,7 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb) 


	mptcp_get_options(skb, &mp_opt);

	if (subflow->request_mptcp) {

		if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC)) {

		if (!(mp_opt.suboptions & OPTION_MPTCP_MPC_SYNACK)) {

			MPTCP_INC_STATS(sock_net(sk),

					MPTCP_MIB_MPCAPABLEACTIVEFALLBACK);

			mptcp_do_fallback(sk);
@@ -783,7 +783,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk, 
		 * options.

		 */

		mptcp_get_options(skb, &mp_opt);

		if (!(mp_opt.suboptions & OPTIONS_MPTCP_MPC))

		if (!(mp_opt.suboptions & OPTION_MPTCP_MPC_ACK))

			fallback = true;



	} else if (subflow_req->mp_join) {