__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
{
+ unsigned int vlan_depth = skb->mac_len;
__be16 type = skb->protocol;
- int vlan_depth = skb->mac_len;
/* Tunnel gso handlers can set protocol to ethernet. */
if (type == htons(ETH_P_TEB)) {
type = eth->h_proto;
}
- while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
- struct vlan_hdr *vh;
-
- if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
- return 0;
-
- vh = (struct vlan_hdr *)(skb->data + vlan_depth);
- type = vh->h_vlan_encapsulated_proto;
- vlan_depth += VLAN_HLEN;
+ /* if skb->protocol is 802.1Q/AD then the header should already be
+ * present at mac_len - VLAN_HLEN (if mac_len > 0), or at
+ * ETH_HLEN otherwise
+ */
+ if (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
+ if (vlan_depth) {
+ if (unlikely(WARN_ON(vlan_depth < VLAN_HLEN)))
+ return 0;
+ vlan_depth -= VLAN_HLEN;
+ } else {
+ vlan_depth = ETH_HLEN;
+ }
+ do {
+ struct vlan_hdr *vh;
+
+ if (unlikely(!pskb_may_pull(skb,
+ vlan_depth + VLAN_HLEN)))
+ return 0;
+
+ vh = (struct vlan_hdr *)(skb->data + vlan_depth);
+ type = vh->h_vlan_encapsulated_proto;
+ vlan_depth += VLAN_HLEN;
+ } while (type == htons(ETH_P_8021Q) ||
+ type == htons(ETH_P_8021AD));
}
*depth = vlan_depth;