Commit 31bf11de authored by Paolo Abeni's avatar Paolo Abeni Committed by Jakub Kicinski
Browse files

mptcp: introduce MAPPING_BAD_CSUM 



This allow moving a couple of conditional out of the fast path,
making the code more easy to follow and will simplify the next
patch.

Fixes: ae66fb2b ("mptcp: Do TCP fallback on early DSS checksum failure")
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 0c1f78a4

net/mptcp/subflow.c

+9 −9
Original line number Diff line number Diff line
@@ -843,7 +843,8 @@ enum mapping_status { 
	MAPPING_INVALID,

	MAPPING_EMPTY,

	MAPPING_DATA_FIN,

	MAPPING_DUMMY

	MAPPING_DUMMY,

	MAPPING_BAD_CSUM

};



static void dbg_bad_map(struct mptcp_subflow_context *subflow, u32 ssn)
@@ -958,9 +959,7 @@ static enum mapping_status validate_data_csum(struct sock *ssk, struct sk_buff * 
				 subflow->map_data_csum);

	if (unlikely(csum)) {

		MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DATACSUMERR);

		if (subflow->mp_join || subflow->valid_csum_seen)

			subflow->send_mp_fail = 1;

		return subflow->mp_join ? MAPPING_INVALID : MAPPING_DUMMY;

		return MAPPING_BAD_CSUM;

	}



	subflow->valid_csum_seen = 1;
@@ -1182,10 +1181,8 @@ static bool subflow_check_data_avail(struct sock *ssk) 


		status = get_mapping_status(ssk, msk);

		trace_subflow_check_data_avail(status, skb_peek(&ssk->sk_receive_queue));

		if (unlikely(status == MAPPING_INVALID))

			goto fallback;



		if (unlikely(status == MAPPING_DUMMY))

		if (unlikely(status == MAPPING_INVALID || status == MAPPING_DUMMY ||

			     status == MAPPING_BAD_CSUM))

			goto fallback;



		if (status != MAPPING_OK)
@@ -1227,7 +1224,10 @@ static bool subflow_check_data_avail(struct sock *ssk) 
fallback:

	if (!__mptcp_check_fallback(msk)) {

		/* RFC 8684 section 3.7. */

		if (subflow->send_mp_fail) {

		if (status == MAPPING_BAD_CSUM &&

		    (subflow->mp_join || subflow->valid_csum_seen)) {

			subflow->send_mp_fail = 1;



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

				ssk->sk_err = EBADMSG;

				tcp_set_state(ssk, TCP_CLOSE);