Commit 2aeef18d authored Jan 28, 2013 by Nivedita Singhvi Committed by David S. Miller Jan 29, 2013

tcp: Increment LISTENOVERFLOW and LISTENDROPS in tcp_v4_conn_request()



We drop a connection request if the accept backlog is full and there are
sufficient packets in the syn queue to warrant starting drops. Increment the
appropriate counters so this isn't silent, for accurate stats and help in
debugging.

This patch assumes LINUX_MIB_LISTENDROPS is a superset of/includes the
counter LINUX_MIB_LISTENOVERFLOWS.

Signed-off-by: Nivedita Singhvi <niv@us.ibm.com>
Acked-by: Vijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 5e98a36e

net/ipv4/tcp_ipv4.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1500,8 +1500,11 @@ int tcp_v4_conn_request(struct sock sk, struct sk_buff skb)
		* clogging syn queue with openreqs with exponentially increasing
		* timeout.
		*/
		if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
		if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) {
		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
		goto drop;
		}

		req = inet_reqsk_alloc(&tcp_request_sock_ops);
		if (!req)

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