Commit 0e4f35d7 authored by Paolo Abeni's avatar Paolo Abeni Committed by Jakub Kicinski
Browse files

mptcp: subflows garbage collection 



The msk can close MP_JOIN subflows if the initial handshake
fails. Currently such subflows are kept alive in the
conn_list until the msk itself is closed.

Beyond the wasted memory, we could end-up sending the
DATA_FIN and the DATA_FIN ack on such socket, even after a
reset.

Fixes: 43b54c6e ("mptcp: Use full MPTCP-level disconnect state machine")
Reviewed-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent d5824847

net/mptcp/protocol.c

+17 −0
Original line number Diff line number Diff line
@@ -1383,6 +1383,20 @@ static void pm_work(struct mptcp_sock *msk) 
	spin_unlock_bh(&msk->pm.lock);

}



static void __mptcp_close_subflow(struct mptcp_sock *msk)

{

	struct mptcp_subflow_context *subflow, *tmp;



	list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) {

		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);



		if (inet_sk_state_load(ssk) != TCP_CLOSE)

			continue;



		__mptcp_close_ssk((struct sock *)msk, ssk, subflow, 0);

	}

}



static void mptcp_worker(struct work_struct *work)

{

	struct mptcp_sock *msk = container_of(work, struct mptcp_sock, work);
@@ -1400,6 +1414,9 @@ static void mptcp_worker(struct work_struct *work) 
	mptcp_clean_una(sk);

	mptcp_check_data_fin_ack(sk);

	__mptcp_flush_join_list(msk);

	if (test_and_clear_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags))

		__mptcp_close_subflow(msk);



	__mptcp_move_skbs(msk);



	if (msk->pm.status)

net/mptcp/protocol.h

+1 −0
Original line number Diff line number Diff line
@@ -90,6 +90,7 @@ 
#define MPTCP_WORK_RTX		2

#define MPTCP_WORK_EOF		3

#define MPTCP_FALLBACK_DONE	4

#define MPTCP_WORK_CLOSE_SUBFLOW 5



struct mptcp_options_received {

	u64	sndr_key;

net/mptcp/subflow.c

+6 −0
Original line number Diff line number Diff line
@@ -272,9 +272,15 @@ static bool subflow_thmac_valid(struct mptcp_subflow_context *subflow) 


void mptcp_subflow_reset(struct sock *ssk)

{

	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);

	struct sock *sk = subflow->conn;



	tcp_set_state(ssk, TCP_CLOSE);

	tcp_send_active_reset(ssk, GFP_ATOMIC);

	tcp_done(ssk);

	if (!test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &mptcp_sk(sk)->flags) &&

	    schedule_work(&mptcp_sk(sk)->work))

		sock_hold(sk);

}



static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)

CRA Git | Maintained and supported by SUSTech CRA and CCSE