[IPV4]: multicast API "join" issues

[net-next-2.6.git] / net / ipv4 / igmp.c

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 111eb678cbac20c80cf6cbc99324cde3f6450d89..e21ebe7599078b0a5fdda868fa69df0fc98ef00b 100644 (file)
--- 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;
 }