Commit 5568e4ca authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'mptcp-misc-fixes' 

Matthieu Baerts says:

====================
mptcp: misc. fixes

Here are two unrelated fixes, plus an extra patch:

- Patch 1: prevent a warning by removing an unneeded and incorrect small
  optimisation in the path-manager. A fix for v5.10.

- Patch 2: reset a subflow when MPTCP opts have been dropped after
  having correctly added a new path. A fix for v5.19.

- Patch 3: add a safety check to prevent issues like the one fixed by
  the second patch.
====================

Link: https://patch.msgid.link/20250224-net-mptcp-misc-fixes-v1-0-f550f636b435@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 18912c52 db75a168

net/mptcp/pm_netlink.c

+0 −5
Original line number Diff line number Diff line
@@ -1514,11 +1514,6 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 
		if (mptcp_pm_is_userspace(msk))

			goto next;



		if (list_empty(&msk->conn_list)) {

			mptcp_pm_remove_anno_addr(msk, addr, false);

			goto next;

		}



		lock_sock(sk);

		remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, addr);

		mptcp_pm_remove_anno_addr(msk, addr, remove_subflow &&

net/mptcp/protocol.h

+2 −0
Original line number Diff line number Diff line
@@ -1199,6 +1199,8 @@ static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 
		pr_debug("TCP fallback already done (msk=%p)\n", msk);

		return;

	}

	if (WARN_ON_ONCE(!READ_ONCE(msk->allow_infinite_fallback)))

		return;

	set_bit(MPTCP_FALLBACK_DONE, &msk->flags);

}

net/mptcp/subflow.c

+1 −14
Original line number Diff line number Diff line
@@ -1142,7 +1142,6 @@ static enum mapping_status get_mapping_status(struct sock *ssk, 
	if (data_len == 0) {

		pr_debug("infinite mapping received\n");

		MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPRX);

		subflow->map_data_len = 0;

		return MAPPING_INVALID;

	}
@@ -1286,18 +1285,6 @@ static void subflow_sched_work_if_closed(struct mptcp_sock *msk, struct sock *ss 
		mptcp_schedule_work(sk);

}



static bool subflow_can_fallback(struct mptcp_subflow_context *subflow)

{

	struct mptcp_sock *msk = mptcp_sk(subflow->conn);



	if (subflow->mp_join)

		return false;

	else if (READ_ONCE(msk->csum_enabled))

		return !subflow->valid_csum_seen;

	else

		return READ_ONCE(msk->allow_infinite_fallback);

}



static void mptcp_subflow_fail(struct mptcp_sock *msk, struct sock *ssk)

{

	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
@@ -1393,7 +1380,7 @@ static bool subflow_check_data_avail(struct sock *ssk) 
			return true;

		}



		if (!subflow_can_fallback(subflow) && subflow->map_data_len) {

		if (!READ_ONCE(msk->allow_infinite_fallback)) {

			/* fatal protocol error, close the socket.

			 * subflow_error_report() will introduce the appropriate barriers

			 */