releases/4.9.136/bridge-do-not-add-port-to-router-list-when-receives-query-with-source-0.0.0.0.patch

   1 From 5a2de63fd1a59c30c02526d427bc014b98adf508 Mon Sep 17 00:00:00 2001
   2 From: Hangbin Liu <liuhangbin@gmail.com>
   3 Date: Fri, 26 Oct 2018 10:28:43 +0800
   4 Subject: bridge: do not add port to router list when receives query with source 0.0.0.0
   5
   6 From: Hangbin Liu <liuhangbin@gmail.com>
   7
   8 commit 5a2de63fd1a59c30c02526d427bc014b98adf508 upstream.
   9
  10 Based on RFC 4541, 2.1.1.  IGMP Forwarding Rules
  11
  12   The switch supporting IGMP snooping must maintain a list of
  13   multicast routers and the ports on which they are attached.  This
  14   list can be constructed in any combination of the following ways:
  15
  16   a) This list should be built by the snooping switch sending
  17      Multicast Router Solicitation messages as described in IGMP
  18      Multicast Router Discovery [MRDISC].  It may also snoop
  19      Multicast Router Advertisement messages sent by and to other
  20      nodes.
  21
  22   b) The arrival port for IGMP Queries (sent by multicast routers)
  23      where the source address is not 0.0.0.0.
  24
  25 We should not add the port to router list when receives query with source
  26 0.0.0.0.
  27
  28 Reported-by: Ying Xu <yinxu@redhat.com>
  29 Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
  30 Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
  31 Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
  32 Signed-off-by: David S. Miller <davem@davemloft.net>
  33 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  34
  35 ---
  36  net/bridge/br_multicast.c |   10 +++++++++-
  37  1 file changed, 9 insertions(+), 1 deletion(-)
  38
  39 --- a/net/bridge/br_multicast.c
  40 +++ b/net/bridge/br_multicast.c
  41 @@ -1287,7 +1287,15 @@ static void br_multicast_query_received(
  42                 return;
  43
  44         br_multicast_update_query_timer(br, query, max_delay);
  45 -       br_multicast_mark_router(br, port);
  46 +
  47 +       /* Based on RFC4541, section 2.1.1 IGMP Forwarding Rules,
  48 +        * the arrival port for IGMP Queries where the source address
  49 +        * is 0.0.0.0 should not be added to router port list.
  50 +        */
  51 +       if ((saddr->proto == htons(ETH_P_IP) && saddr->u.ip4) ||
  52 +           (saddr->proto == htons(ETH_P_IPV6) &&
  53 +            !ipv6_addr_any(&saddr->u.ip6)))
  54 +               br_multicast_mark_router(br, port);
  55  }
  56
  57  static int br_ip4_multicast_query(struct net_bridge *br,