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 cf75f8944b05eb302c11cd8e2e0e9f762ab7e35c..deb1f8274d71a293fa4d731bf6ad6c4170a22b46 100644 (file)
--- 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);