Merging upstream version 5.10.216.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 58d8e6260..1f016af06 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -333,6 +333,39 @@ static inline bool pskb_inet_may_pull(struct sk_buff *skb)
 	return pskb_network_may_pull(skb, nhlen);
 }
 
+/* Variant of pskb_inet_may_pull().
+ */
+static inline bool skb_vlan_inet_prepare(struct sk_buff *skb)
+{
+	int nhlen = 0, maclen = ETH_HLEN;
+	__be16 type = skb->protocol;
+
+	/* Essentially this is skb_protocol(skb, true)
+	 * And we get MAC len.
+	 */
+	if (eth_type_vlan(type))
+		type = __vlan_get_protocol(skb, type, &maclen);
+
+	switch (type) {
+#if IS_ENABLED(CONFIG_IPV6)
+	case htons(ETH_P_IPV6):
+		nhlen = sizeof(struct ipv6hdr);
+		break;
+#endif
+	case htons(ETH_P_IP):
+		nhlen = sizeof(struct iphdr);
+		break;
+	}
+	/* For ETH_P_IPV6/ETH_P_IP we make sure to pull
+	 * a base network header in skb->head.
+	 */
+	if (!pskb_may_pull(skb, maclen + nhlen))
+		return false;
+
+	skb_set_network_header(skb, maclen);
+	return true;
+}
+
 static inline int ip_encap_hlen(struct ip_tunnel_encap *e)
 {
 	const struct ip_tunnel_encap_ops *ops;