Based on RFC 4541, 2.1.1. IGMP Forwarding Rules
The switch supporting IGMP snooping must maintain a list of
multicast routers and the ports on which they are attached. This
list can be constructed in any combination of the following ways:
a) This list should be built by the snooping switch sending
Multicast Router Solicitation messages as described in IGMP
Multicast Router Discovery [MRDISC]. It may also snoop
Multicast Router Advertisement messages sent by and to other
nodes.
b) The arrival port for IGMP Queries (sent by multicast routers)
where the source address is not 0.0.0.0.
We should not add the port to router list when receives query with source
0.0.0.0.
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
5a2de63fd1