From b09ab9c92e5077a00602dbff606ea518f379303c Mon Sep 17 00:00:00 2001 From: Matthias May Date: Mon, 11 Jul 2022 11:17:22 +0200 Subject: [PATCH] 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 Signed-off-by: David S. Miller --- net/ipv6/ip6_tunnel.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index c7279f205817..3fda5634578c 100644 --- 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); -- 2.39.5