1 files changed, 9 insertions, 0 deletions

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 111eb678cbac..e21ebe759907 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1724,6 +1724,7 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
         struct in_device *in_dev = NULL;
         struct inet_sock *inet = inet_sk(sk);
         struct ip_sf_socklist *psl;
+        int leavegroup = 0;
         int i, j, rv;
 
         if (!MULTICAST(addr))
@@ -1775,6 +1776,12 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
                 if (rv)         /* source not found */
                         goto done;
 
+                /* special case - (INCLUDE, empty) == LEAVE_GROUP */
+                if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
+                        leavegroup = 1;
+                        goto done;
+                }
+
                 /* update the interface filter */
                 ip_mc_del_src(in_dev, &mreqs->imr_multiaddr, omode, 1, 
                         &mreqs->imr_sourceaddr, 1);
@@ -1831,6 +1838,8 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
                 &mreqs->imr_sourceaddr, 1);
 done:
         rtnl_shunlock();
+        if (leavegroup)
+                return ip_mc_leave_group(sk, &imr);
         return err;
 }