Multicast packets are not bridged from ethernet to wireless interface

[saurav barik <saurav.barik@xxxxxxxxx>]

Hello,

I am working on an Access Point device (AP1) running linux kernel 3.0.34 on which my bridge configuration is as follows.

~ # brctl show
bridge name     bridge id               STP enabled     interfaces
mbr             8000.xxxxxxxx0271       no                eth1
                                                                          wlan0

wlan0 is connected by a wlan link to another access point AP2. This mbr on AP1 gets IP address via wlan0. I have a laptop connected to eth1 interface and it too gets IP address via eth1-bridged-wlan0 (wlan0 is the only uplink port). All the unicast packets (ping traffic) from the laptop via eth1-bridged-wlan0 works fine. However when I start a multicast tx (iperf multicast) from the laptop, the multicast packet reaches eth1 and then gets dropped in the bridge module. I debugged and found the packets are dropped at -

br_multicast_flood(struct net_bridge_mdb_entry *mdst, ....)

.... <code snippet>

        while (p || rp) {
....       
        rp = rcu_dereference(hlist_first_rcu(&br->router_list));
        p = mdst ? rcu_dereference(mdst->ports) : NULL;
        }

        if (!prev)
        {

 /******* packets getting dropped here.  *********/

                goto out;
        }
........

The three pointers mdst, p and rp  are NULL. Prior to reaching here, the packet traversed successfully via br_handle_frame()->br_handle_frame_finish()->br_multicast_forward()->br_multicast_flood(). The source and multicast destination address in the skb look alright.

Additional Note: I have another ethernet interface on AP1 which is eth0. If I remove wlan0 and add eth0, then multicast packets successfully pass from eth1 to eth0 in the bridge module.

Could anybody share some pointer on this? Thank you.

With Regards,

Saurav