From e89d4eec3eda03ea6b2a31bbe17159edf584da9b Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Fri, 16 Mar 2018 11:29:10 +0100 Subject: batman-adv: fix header size check in batadv_dbg_arp() [ Upstream commit 6f27d2c2a8c236d296201c19abb8533ec20d212b ] Checking for 0 is insufficient: when an SKB without a batadv header, but with a VLAN header is received, hdr_size will be 4, making the following code interpret the Ethernet header as a batadv header. Fixes: be1db4f6615b ("batman-adv: make the Distributed ARP Table vlan aware") Signed-off-by: Matthias Schiffer Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/distributed-arp-table.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 5f19133c5530..c2dff7c6e960 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -374,7 +374,7 @@ static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb, batadv_arp_hw_src(skb, hdr_size), &ip_src, batadv_arp_hw_dst(skb, hdr_size), &ip_dst); - if (hdr_size == 0) + if (hdr_size < sizeof(struct batadv_unicast_packet)) return; unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data; -- cgit v1.2.3