Commit b6dc01a4 authored by James Chapman's avatar James Chapman Committed by David S. Miller
Browse files

l2tp: do data sequence number handling in a separate func 



This change moves some code handling data sequence numbers into a
separate function to avoid too much indentation. This is to prepare
for some changes to data sequence number handling in subsequent
patches.

Signed-off-by: default avatarJames Chapman <jchapman@katalix.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8a59bd3e

net/l2tp/l2tp_core.c

+34 −20
Original line number Diff line number Diff line
@@ -542,6 +542,38 @@ static inline int l2tp_verify_udp_checksum(struct sock *sk, 
	return __skb_checksum_complete(skb);

}



/* If packet has sequence numbers, queue it if acceptable. Returns 0 if

 * acceptable, else non-zero.

 */

static int l2tp_recv_data_seq(struct l2tp_session *session, struct sk_buff *skb)

{

	if (session->reorder_timeout != 0) {

		/* Packet reordering enabled. Add skb to session's

		 * reorder queue, in order of ns.

		 */

		l2tp_recv_queue_skb(session, skb);

	} else {

		/* Packet reordering disabled. Discard out-of-sequence

		 * packets

		 */

		if (L2TP_SKB_CB(skb)->ns != session->nr) {

			atomic_long_inc(&session->stats.rx_seq_discards);

			l2tp_dbg(session, L2TP_MSG_SEQ,

				 "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n",

				 session->name, L2TP_SKB_CB(skb)->ns,

				 L2TP_SKB_CB(skb)->length, session->nr,

				 skb_queue_len(&session->reorder_q));

			goto discard;

		}

		skb_queue_tail(&session->reorder_q, skb);

	}



	return 0;



discard:

	return 1;

}



/* Do receive processing of L2TP data frames. We handle both L2TPv2

 * and L2TPv3 data frames here.

 *
@@ -757,26 +789,8 @@ void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, 
	 * enabled. Saved L2TP protocol info is stored in skb->sb[].

	 */

	if (L2TP_SKB_CB(skb)->has_seq) {

		if (session->reorder_timeout != 0) {

			/* Packet reordering enabled. Add skb to session's

			 * reorder queue, in order of ns.

			 */

			l2tp_recv_queue_skb(session, skb);

		} else {

			/* Packet reordering disabled. Discard out-of-sequence

			 * packets

			 */

			if (L2TP_SKB_CB(skb)->ns != session->nr) {

				atomic_long_inc(&session->stats.rx_seq_discards);

				l2tp_dbg(session, L2TP_MSG_SEQ,

					 "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n",

					 session->name, L2TP_SKB_CB(skb)->ns,

					 L2TP_SKB_CB(skb)->length, session->nr,

					 skb_queue_len(&session->reorder_q));

		if (l2tp_recv_data_seq(session, skb))

			goto discard;

			}

			skb_queue_tail(&session->reorder_q, skb);

		}

	} else {

		/* No sequence numbers. Add the skb to the tail of the

		 * reorder queue. This ensures that it will be

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