From: Hangbin Liu <liuhangbin@gmail.com>
Date: Wed, 29 Aug 2018 10:06:08 +0000 (+0800)
Subject: igmp: fix incorrect unsolicit report count when join group
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=4fb7253e4f9a8f06a986a3b317e2f79d9b43d552;p=openwrt%2Fstaging%2Fblogic.git

igmp: fix incorrect unsolicit report count when join group

We should not start timer if im->unsolicit_count equal to 0 after decrease.
Or we will send one more unsolicit report message. i.e. 3 instead of 2 by
default.

Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index cf75f8944b05..deb1f8274d71 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -820,10 +820,9 @@ static void igmp_timer_expire(struct timer_list *t)
 	spin_lock(&im->lock);
 	im->tm_running = 0;
 
-	if (im->unsolicit_count) {
-		im->unsolicit_count--;
+	if (im->unsolicit_count && --im->unsolicit_count)
 		igmp_start_timer(im, unsolicited_report_interval(in_dev));
-	}
+
 	im->reporter = 1;
 	spin_unlock(&im->lock);