[X25]: Fix to be PKT_CAN_SHARE_SKB.

net/x25/af_x25.c

@@ -1345,6 +1345,7 @@ SOCKOPS_WRAP(x25_proto, AF_X25);
 static struct packet_type x25_packet_type = {
 	.type =	__constant_htons(ETH_P_X25),
 	.func =	x25_lapb_receive_frame,
+	.data = PKT_CAN_SHARE_SKB,
 };
 
 struct notifier_block x25_dev_notifier = {

net/x25/x25_dev.c

@@ -100,9 +100,14 @@ static int x25_receive_data(struct sk_buff *skb, struct x25_neigh *nb)
 int x25_lapb_receive_frame(struct sk_buff *skb, struct net_device *dev,
 			   struct packet_type *ptype)
 {
+	struct sk_buff *nskb;
 	struct x25_neigh *nb;
 
-	skb->sk = NULL;
+	nskb = skb_copy(skb, GFP_ATOMIC);
+	if (!nskb)
+		goto drop;
+	kfree_skb(skb);
+	skb = nskb;
 
 	/*
 	 * Packet received from unrecognised device, throw it away.