bridge: do not add port to router list when receives query with source 0.0.0.0
authorHangbin Liu <liuhangbin@gmail.com>
Fri, 26 Oct 2018 02:28:43 +0000 (10:28 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 4 Nov 2018 13:52:48 +0000 (14:52 +0100)
commit1bd68d5612af83ed392f066861eb5033bfcad28c
tree1a39f4f7d37241b4e38a0b80b8cd3fb5c13f0f27
parentb6534b3e08e8e10e871b53ce5a1e9ce4bcb94907
bridge: do not add port to router list when receives query with source 0.0.0.0

commit 5a2de63fd1a59c30c02526d427bc014b98adf508 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/bridge/br_multicast.c