From 7795fea34180ddf093d2f7cbdcabc9aa7630a0bc Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Fri, 22 May 2015 12:18:59 -0300 Subject: bridge: fix parsing of MLDv2 reports commit 47cc84ce0c2fe75c99ea5963c4b5704dd78ead54 upstream. When more than a multicast address is present in a MLDv2 report, all but the first address is ignored, because the code breaks out of the loop if there has not been an error adding that address. This has caused failures when two guests connected through the bridge tried to communicate using IPv6. Neighbor discoveries would not be transmitted to the other guest when both used a link-local address and a static address. This only happens when there is a MLDv2 querier in the network. The fix will only break out of the loop when there is a failure adding a multicast address. The mdb before the patch: dev ovirtmgmt port vnet0 grp ff02::1:ff7d:6603 temp dev ovirtmgmt port vnet1 grp ff02::1:ff7d:6604 temp dev ovirtmgmt port bond0.86 grp ff02::2 temp After the patch: dev ovirtmgmt port vnet0 grp ff02::1:ff7d:6603 temp dev ovirtmgmt port vnet1 grp ff02::1:ff7d:6604 temp dev ovirtmgmt port bond0.86 grp ff02::fb temp dev ovirtmgmt port bond0.86 grp ff02::2 temp dev ovirtmgmt port bond0.86 grp ff02::d temp dev ovirtmgmt port vnet0 grp ff02::1:ff00:76 temp dev ovirtmgmt port bond0.86 grp ff02::16 temp dev ovirtmgmt port vnet1 grp ff02::1:ff00:77 temp dev ovirtmgmt port bond0.86 grp ff02::1:ff00:def temp dev ovirtmgmt port bond0.86 grp ff02::1:ffa1:40bf temp Fixes: 08b202b67264 ("bridge br_multicast: IPv6 MLD support.") Reported-by: Rik Theys Signed-off-by: Thadeu Lima de Souza Cascardo Tested-by: Rik Theys Signed-off-by: David S. Miller [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings Cc: Jonathan Toppins --- net/bridge/br_multicast.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 398a297..6f20485 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -972,7 +972,7 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br, } err = br_ip6_multicast_add_group(br, port, &grec->grec_mca); - if (!err) + if (err) break; } -- cgit v1.1