From 848bf15f361c7c22da7998c81d50ed3dffbc827d Mon Sep 17 00:00:00 2001
From: Vijay Subramanian <subramanian.vijay@gmail.com>
Date: Thu, 31 Jan 2013 08:24:06 +0000
Subject: [PATCH] tcp: Update MIB counters for drops

This patch updates LINUX_MIB_LISTENDROPS in tcp_v4_conn_request() and
tcp_v4_err(). tcp_v4_conn_request() in particular can drop SYNs for various
reasons which are not currently tracked.

Signed-off-by: Vijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/ipv4/tcp_ipv4.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 629937d514eb..eadb693eef55 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -496,6 +496,7 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
 		 * errors returned from accept().
 		 */
 		inet_csk_reqsk_queue_drop(sk, req, prev);
+		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
 		goto out;
 
 	case TCP_SYN_SENT:
@@ -1502,7 +1503,6 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 	 */
 	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;
 	}
 
@@ -1669,6 +1669,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 drop_and_free:
 	reqsk_free(req);
 drop:
+	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
 	return 0;
 }
 EXPORT_SYMBOL(tcp_v4_conn_request);
-- 
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