l2tp: test for ethernet header in l2tp_eth_dev_recv()
close https://bugzilla.kernel.org/show_bug.cgi?id=16529
Before calling dev_forward_skb(), we should make sure skb head contains
at least an ethernet header, even if length included in upper layer said
so. Use pskb_may_pull() to make sure this ethernet header is present in
skb head.
Reported-by: Thomas Heil <heil@terminal-consulting.de>
Reported-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c
index 58c6c4c..1ae6976 100644
--- a/net/l2tp/l2tp_eth.c
+++ b/net/l2tp/l2tp_eth.c
@@ -132,7 +132,7 @@
printk("\n");
}
- if (data_len < ETH_HLEN)
+ if (!pskb_may_pull(skb, sizeof(ETH_HLEN)))
goto error;
secpath_reset(skb);