bridge: Pull ip header into skb->data before looking into ip header.

If lower layer driver leaves the ip header in the skb fragment, it needs to
be first pulled into skb->data before inspecting ip header length or ip version
number.

Signed-off-by: Sarveshwar Bandi <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index 68e8f364bbf8e01fbae9134eb98a24fa676d0e51..fe43bc7b063f5f49b31c237f3f418b56de15379d 100644 (file)
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -265,6 +265,9 @@ static int br_parse_ip_options(struct sk_buff *skb)
        struct net_device *dev = skb->dev;
        u32 len;
 
+       if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+               goto inhdr_error;
+
        iph = ip_hdr(skb);
        opt = &(IPCB(skb)->opt);