bridge: prevent bridging wrong device
The bridge code assumes ethernet addressing, so be more strict in
the what is allowed. This showed up when GRE had a bug and was not
using correct address format.
Add some more comments for increased clarity.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index b1b3b0f..4a9f527 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -377,12 +377,16 @@
struct net_bridge_port *p;
int err = 0;
- if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
+ /* Don't allow bridging non-ethernet like devices */
+ if ((dev->flags & IFF_LOOPBACK) ||
+ dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN)
return -EINVAL;
+ /* No bridging of bridges */
if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit)
return -ELOOP;
+ /* Device is already being bridged */
if (dev->br_port != NULL)
return -EBUSY;