• Thadeu Lima de Souza Cascardo's avatar
    bridge: fix parsing of MLDv2 reports · 47cc84ce
    Thadeu Lima de Souza Cascardo authored
    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: 08b202b6 ("bridge br_multicast: IPv6 MLD support.")
    Reported-by: default avatarRik Theys <Rik.Theys@esat.kuleuven.be>
    Signed-off-by: default avatarThadeu Lima de Souza Cascardo <cascardo@redhat.com>
    Tested-by: default avatarRik Theys <Rik.Theys@esat.kuleuven.be>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    47cc84ce
br_multicast.c 51.1 KB