Repository : ssh://git@open-mesh.org/batman-adv

On branch : maint

commit 7d2f8a773bae5e07cadc9a9f74ac21abe32cde13 Author: Sven Eckelmann sven@narfation.org Date: Fri Feb 26 17:56:13 2016 +0100

batman-adv: Check skb size before using encapsulated ETH+VLAN header

The encapsulated ethernet and VLAN header may be outside the received ethernet frame. Thus the skb buffer size has to be checked before it can be parsed to find out if it encapsulates another batman-adv packet.

Fixes: 48628bb9419f ("batman-adv: softif bridge loop avoidance") Signed-off-by: Sven Eckelmann sven@narfation.org Signed-off-by: Marek Lindner mareklindner@neomailbox.ch

7d2f8a773bae5e07cadc9a9f74ac21abe32cde13 net/batman-adv/soft-interface.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 6c65de9..64d721c 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -407,11 +407,17 @@ void batadv_interface_rx(struct net_device *soft_iface, */ nf_reset(skb);

+ if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) + goto dropped; + vid = batadv_get_vid(skb, 0); ethhdr = eth_hdr(skb);

switch (ntohs(ethhdr->h_proto)) { case ETH_P_8021Q: + if (!pskb_may_pull(skb, VLAN_ETH_HLEN)) + goto dropped; + vhdr = (struct vlan_ethhdr *)skb->data;

if (vhdr->h_vlan_encapsulated_proto != ethertype) @@ -423,8 +429,6 @@ void batadv_interface_rx(struct net_device *soft_iface, }

/* skb->dev & skb->pkt_type are set here */ - if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) - goto dropped; skb->protocol = eth_type_trans(skb, soft_iface);

/* should not be necessary anymore as we use skb_pull_rcsum()