ip6_tunnel: allow to inherit from VLAN encapsulated IP

The current code allows to inherit the TTL (hop_limit) from the
payload when skb->protocol is ETH_P_IP or ETH_P_IPV6.
However when the payload is VLAN encapsulated (e.g because the tunnel
is of type GRETAP), then this inheriting does not work, because the
visible skb->protocol is of type ETH_P_8021Q or ETH_P_8021AD.

Instead of skb->protocol, use skb_protocol().

Signed-off-by: Matthias May <matthias.may@westermo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index c7279f205817bd9017076657230d93a3086a0bf1..3fda5634578ce672a90ca5977838071a66156aa3 100644 (file)
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1080,10 +1080,13 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
        unsigned int eth_hlen = t->dev->type == ARPHRD_ETHER ? ETH_HLEN : 0;
        unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
        unsigned int max_headroom = psh_hlen;
+       __be16 payload_protocol;
        bool use_cache = false;
        u8 hop_limit;
        int err = -1;
 
+       payload_protocol = skb_protocol(skb, true);
+
        if (t->parms.collect_md) {
                hop_limit = skb_tunnel_info(skb)->key.ttl;
                goto route_lookup;
@@ -1093,7 +1096,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
 
        /* NBMA tunnel */
        if (ipv6_addr_any(&t->parms.raddr)) {
-               if (skb->protocol == htons(ETH_P_IPV6)) {
+               if (payload_protocol == htons(ETH_P_IPV6)) {
                        struct in6_addr *addr6;
                        struct neighbour *neigh;
                        int addr_type;
@@ -1114,7 +1117,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
 
                        memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
                        neigh_release(neigh);
-               } else if (skb->protocol == htons(ETH_P_IP)) {
+               } else if (payload_protocol == htons(ETH_P_IP)) {
                        const struct rtable *rt = skb_rtable(skb);
 
                        if (!rt)
@@ -1225,9 +1228,9 @@ route_lookup:
        skb_dst_set(skb, dst);
 
        if (hop_limit == 0) {
-               if (skb->protocol == htons(ETH_P_IP))
+               if (payload_protocol == htons(ETH_P_IP))
                        hop_limit = ip_hdr(skb)->ttl;
-               else if (skb->protocol == htons(ETH_P_IPV6))
+               else if (payload_protocol == htons(ETH_P_IPV6))
                        hop_limit = ipv6_hdr(skb)->hop_limit;
                else
                        hop_limit = ip6_dst_hoplimit(dst);