diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 6e9a59e..46bdd0d 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1908,8 +1908,11 @@
 		skb->dev = tun->dev;
 		break;
 	case IFF_TAP:
-		if (!frags)
-			skb->protocol = eth_type_trans(skb, tun->dev);
+		if (frags && !pskb_may_pull(skb, ETH_HLEN)) {
+			err = -ENOMEM;
+			goto drop;
+		}
+		skb->protocol = eth_type_trans(skb, tun->dev);
 		break;
 	}
 
@@ -1966,9 +1969,12 @@
 	}
 
 	if (frags) {
+		u32 headlen;
+
 		/* Exercise flow dissector code path. */
-		u32 headlen = eth_get_headlen(tun->dev, skb->data,
-					      skb_headlen(skb));
+		skb_push(skb, ETH_HLEN);
+		headlen = eth_get_headlen(tun->dev, skb->data,
+					  skb_headlen(skb));
 
 		if (unlikely(headlen > skb_headlen(skb))) {
 			this_cpu_inc(tun->pcpu_stats->rx_dropped);