diff options
| author | Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> | 2014-05-26 15:15:53 +0900 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-06-02 13:38:23 -0700 |
| commit | e0d7968ab6c8bce2437b36fa7f04117e333f196d (patch) | |
| tree | 8b066b3ba7134569ba12b5dd21b31be2621adf3c /net/bridge/br_vlan.c | |
| parent | bfc5184b69cf9eeb286137640351c650c27f118a (diff) | |
bridge: Prevent insertion of FDB entry with disallowed vlan
br_handle_local_finish() is allowing us to insert an FDB entry with
disallowed vlan. For example, when port 1 and 2 are communicating in
vlan 10, and even if vlan 10 is disallowed on port 3, port 3 can
interfere with their communication by spoofed src mac address with
vlan id 10.
Note: Even if it is judged that a frame should not be learned, it should
not be dropped because it is destined for not forwarding layer but higher
layer. See IEEE 802.1Q-2011 8.13.10.
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/bridge/br_vlan.c')
| -rw-r--r-- | net/bridge/br_vlan.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c index 4a3716102789..5fee2feaf292 100644 --- a/net/bridge/br_vlan.c +++ b/net/bridge/br_vlan.c @@ -241,6 +241,34 @@ bool br_allowed_egress(struct net_bridge *br, return false; } +/* Called under RCU */ +bool br_should_learn(struct net_bridge_port *p, struct sk_buff *skb, u16 *vid) +{ + struct net_bridge *br = p->br; + struct net_port_vlans *v; + + if (!br->vlan_enabled) + return true; + + v = rcu_dereference(p->vlan_info); + if (!v) + return false; + + br_vlan_get_tag(skb, vid); + if (!*vid) { + *vid = br_get_pvid(v); + if (*vid == VLAN_N_VID) + return false; + + return true; + } + + if (test_bit(*vid, v->vlan_bitmap)) + return true; + + return false; +} + /* Must be protected by RTNL. * Must be called with vid in range from 1 to 4094 inclusive. */ |