From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jun Zhao <mypopydev@gmail.com>
Subject: [patch] fix error handle in ip_mc_add_src()
Date: Mon, 21 Nov 2011 23:51:40 +0800
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Cc: netdev@vger.kernel.org, Eric Dumazet <eric.dumazet@gmail.com>,
	David Stevens <dlstevens@us.ibm.com>
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from: Jun Zhao <mypopydev@gmail.com>

When add sources to interface failure, need to roll back the sfcount[MODE] 
to before state. We need to match it corresponding. 

Signed-off-by: Jun Zhao <mypopydev@gmail.com>
---
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index c7472ef..b2ca095 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1716,7 +1716,8 @@ static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
 	if (err) {
 		int j;
 
-		pmc->sfcount[sfmode]--;
+		if (!delta)
+			pmc->sfcount[sfmode]--;
 		for (j=0; j<i; j++)
 			(void) ip_mc_del1_src(pmc, sfmode, &psfsrc[j]);
 	} else if (isexclude != (pmc->sfcount[MCAST_EXCLUDE] != 0)) {