batman-adv: check incoming packet type for bla
If the gateway functionality is used, some broadcast packets (DHCP
requests) may be transmitted as unicast packets. As the bridge loop
avoidance code now only considers the payload Ethernet destination,
it may drop the DHCP request for clients which are claimed by other
backbone gateways, because it falsely infers from the broadcast address
that the right backbone gateway should havehandled the broadcast.
Fix this by checking and delegating the batman-adv packet type used
for transmission.
Reported-by: Guido Iribarren <guidoiribarren@buenosaireslibre.org>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 6e2530b..a0ec0e4 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -256,7 +256,11 @@
struct bat_priv *bat_priv = netdev_priv(soft_iface);
struct ethhdr *ethhdr;
struct vlan_ethhdr *vhdr;
+ struct batman_header *batadv_header = (struct batman_header *)skb->data;
short vid __maybe_unused = -1;
+ bool is_bcast;
+
+ is_bcast = (batadv_header->packet_type == BAT_BCAST);
/* check if enough space is available for pulling, and pull */
if (!pskb_may_pull(skb, hdr_size))
@@ -302,7 +306,7 @@
/* Let the bridge loop avoidance check the packet. If will
* not handle it, we can safely push it up.
*/
- if (bla_rx(bat_priv, skb, vid))
+ if (bla_rx(bat_priv, skb, vid, is_bcast))
goto out;
netif_rx(skb);