• Nikolay Aleksandrov's avatar
    bridge: mdb: zero out the local br_ip variable before use · f07f6f98
    Nikolay Aleksandrov authored
    commit f1158b74 upstream.
    
    Since commit b0e9a30d ("bridge: Add vlan id to multicast groups")
    there's a check in br_ip_equal() for a matching vlan id, but the mdb
    functions were not modified to use (or at least zero it) so when an
    entry was added it would have a garbage vlan id (from the local br_ip
    variable in __br_mdb_add/del) and this would prevent it from being
    matched and also deleted. So zero out the whole local ip var to protect
    ourselves from future changes and also to fix the current bug, since
    there's no vlan id support in the mdb uapi - use always vlan id 0.
    Example before patch:
    root@debian:~# bridge mdb add dev br0 port eth1 grp 239.0.0.1 permanent
    root@debian:~# bridge mdb
    dev br0 port eth1 grp 239.0.0.1 permanent
    root@debian:~# bridge mdb del dev br0 port eth1 grp 239.0.0.1 permanent
    RTNETLINK answers: Invalid argument
    
    After patch:
    root@debian:~# bridge mdb add dev br0 port eth1 grp 239.0.0.1 permanent
    root@debian:~# bridge mdb
    dev br0 port eth1 grp 239.0.0.1 permanent
    root@debian:~# bridge mdb del dev br0 port eth1 grp 239.0.0.1 permanent
    root@debian:~# bridge mdb
    Signed-off-by: default avatarNikolay Aleksandrov <razor@blackwall.org>
    Fixes: b0e9a30d ("bridge: Add vlan id to multicast groups")
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
    f07f6f98
br_mdb.c 11.2 KB