gre: set inner_protocol on xmit

Ensure that the inner_protocol is set on transmit so that GSO segmentation, which relies on that field, works correctly. This is achieved by setting the inner_protocol in gre_build_header rather than each caller of that function. It ensures that the inner_protocol is set when gre_fb_xmit() is used to transmit GRE which was not previously the case. I have observed this is not the case when OvS transmits GRE using lwtunnel metadata (which it always does). Fixes: 3872035 ("gre: Use inner_proto to obtain inner header protocol") Cc: Pravin Shelar <[email protected]> Acked-by: Alexander Duyck <[email protected]> Signed-off-by: Simon Horman <[email protected]> Acked-by: Pravin B Shelar <[email protected]> Signed-off-by: David S. Miller <[email protected]>
dabrace · Aug 15, 2016 · 3d7b332 · 3d7b332
1 parent 5e45789
commit 3d7b332
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Showing 3 changed files with 1 addition and 3 deletions.
diff --git a/include/net/gre.h b/include/net/gre.h
@@ -104,6 +104,7 @@ static inline void gre_build_header(struct sk_buff *skb, int hdr_len,
 
 	skb_push(skb, hdr_len);
 
+	skb_set_inner_protocol(skb, proto);
 	skb_reset_transport_header(skb);
 	greh = (struct gre_base_hdr *)skb->data;
 	greh->flags = gre_tnl_flags_to_gre_flags(flags);

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
@@ -370,7 +370,6 @@ static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
 			 tunnel->parms.o_flags, proto, tunnel->parms.o_key,
 			 htonl(tunnel->o_seqno));
 
-	skb_set_inner_protocol(skb, proto);
 	ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
 }
 

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
@@ -519,8 +519,6 @@ static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
 	gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
 			 protocol, tunnel->parms.o_key, htonl(tunnel->o_seqno));
 
-	skb_set_inner_protocol(skb, protocol);
-
 	return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
 			    NEXTHDR_GRE);
 }