net: Fix missing meta data in skb with vlan packet

skb_reorder_vlan_header() should move XDP meta data with ethernet header
if XDP meta data exists.

Fixes: de8f3a83 ("bpf: add meta pointer for direct access")
Signed-off-by: Yuya Kusakabe <yuya.kusakabe@gmail.com>
Signed-off-by: Takeru Hayasaka <taketarou2@gmail.com>
Co-developed-by: Takeru Hayasaka <taketarou2@gmail.com>
Reviewed-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/skbuff.c

@@ -5083,7 +5083,8 @@ EXPORT_SYMBOL_GPL(skb_gso_validate_mac_len);
 
 static struct sk_buff *skb_reorder_vlan_header(struct sk_buff *skb)
 {
-	int mac_len;
+	int mac_len, meta_len;
+	void *meta;
 
 	if (skb_cow(skb, skb_headroom(skb)) < 0) {
 		kfree_skb(skb);
@@ -5095,6 +5096,13 @@ static struct sk_buff *skb_reorder_vlan_header(struct sk_buff *skb)
 		memmove(skb_mac_header(skb) + VLAN_HLEN, skb_mac_header(skb),
 			mac_len - VLAN_HLEN - ETH_TLEN);
 	}
+
+	meta_len = skb_metadata_len(skb);
+	if (meta_len) {
+		meta = skb_metadata_end(skb) - meta_len;
+		memmove(meta + VLAN_HLEN, meta, meta_len);
+	}
+
 	skb->mac_header += VLAN_HLEN;
 	return skb;
 }