ipv6: set skb->protocol on tcp, raw and ip6_append_data genereated skbs

Currently we don't initialize skb->protocol when transmitting data via
tcp, raw(with and without inclhdr) or udp+ufo or appending data directly
to the socket transmit queue (via ip6_append_data). This needs to be
done so that we can get the correct mtu in the xfrm layer.

Setting of skb->protocol happens only in functions where we also have
a transmitting socket and a new skb, so we don't overwrite old values.

Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

2 files changed, 4 insertions, 0 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 6e3ddf806ec2..e7ceb6c871d1 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -238,6 +238,7 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
         hdr->saddr = fl6->saddr;
         hdr->daddr = *first_hop;
 
+        skb->protocol = htons(ETH_P_IPV6);
         skb->priority = sk->sk_priority;
         skb->mark = sk->sk_mark;
 
@@ -1057,6 +1058,7 @@ static inline int ip6_ufo_append_data(struct sock *sk,
                 /* initialize protocol header pointer */
                 skb->transport_header = skb->network_header + fragheaderlen;
 
+                skb->protocol = htons(ETH_P_IPV6);
                 skb->ip_summed = CHECKSUM_PARTIAL;
                 skb->csum = 0;
         }
@@ -1359,6 +1361,7 @@ alloc_new_skb:
                         /*
                          *      Fill in the control structures
                          */
+                        skb->protocol = htons(ETH_P_IPV6);
                         skb->ip_summed = CHECKSUM_NONE;
                         skb->csum = 0;
                         /* reserve for fragmentation and ipsec header */
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index c45f7a5c36e9..cdaed47ba932 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -628,6 +628,7 @@ static int rawv6_send_hdrinc(struct sock *sk, void *from, int length,
                 goto error;
         skb_reserve(skb, hlen);
 
+        skb->protocol = htons(ETH_P_IPV6);
         skb->priority = sk->sk_priority;
         skb->mark = sk->sk_mark;
         skb_dst_set(skb, &rt->dst);