1 files changed, 44 insertions, 13 deletions

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 3e4184088082..63f7bacf628a 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -399,7 +399,10 @@ static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
 				  iph->saddr, iph->daddr, tpi->key);
 
 	if (tunnel) {
-		skb_pop_mac_header(skb);
+		if (tunnel->dev->type != ARPHRD_NONE)
+			skb_pop_mac_header(skb);
+		else
+			skb_reset_mac_header(skb);
 		if (tunnel->collect_md) {
 			__be16 flags;
 			__be64 tun_id;
@@ -499,6 +502,10 @@ static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
 static struct sk_buff *gre_handle_offloads(struct sk_buff *skb,
 					   bool csum)
 {
+	unsigned char *skb_checksum_start = skb->head + skb->csum_start;
+
+	if (csum && skb_checksum_start < skb->data)
+		return ERR_PTR(-EINVAL);
 	return iptunnel_handle_offloads(skb, csum,
 					csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
 }
@@ -520,7 +527,8 @@ static struct rtable *gre_get_rt(struct sk_buff *skb,
 	return ip_route_output_key(net, fl);
 }
 
-static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev)
+static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
+			__be16 proto)
 {
 	struct ip_tunnel_info *tun_info;
 	const struct ip_tunnel_key *key;
@@ -563,7 +571,7 @@ static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev)
 	}
 
 	flags = tun_info->key.tun_flags & (TUNNEL_CSUM | TUNNEL_KEY);
-	build_header(skb, tunnel_hlen, flags, htons(ETH_P_TEB),
+	build_header(skb, tunnel_hlen, flags, proto,
 		     tunnel_id_to_key(tun_info->key.tun_id), 0);
 
 	df = key->tun_flags & TUNNEL_DONT_FRAGMENT ?  htons(IP_DF) : 0;
@@ -605,7 +613,7 @@ static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
 	const struct iphdr *tnl_params;
 
 	if (tunnel->collect_md) {
-		gre_fb_xmit(skb, dev);
+		gre_fb_xmit(skb, dev, skb->protocol);
 		return NETDEV_TX_OK;
 	}
 
@@ -649,7 +657,7 @@ static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
 	struct ip_tunnel *tunnel = netdev_priv(dev);
 
 	if (tunnel->collect_md) {
-		gre_fb_xmit(skb, dev);
+		gre_fb_xmit(skb, dev, htons(ETH_P_TEB));
 		return NETDEV_TX_OK;
 	}
 
@@ -851,9 +859,16 @@ static void __gre_tunnel_init(struct net_device *dev)
 	dev->hw_features	|= GRE_FEATURES;
 
 	if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) {
-		/* TCP offload with GRE SEQ is not supported. */
-		dev->features    |= NETIF_F_GSO_SOFTWARE;
-		dev->hw_features |= NETIF_F_GSO_SOFTWARE;
+		/* TCP offload with GRE SEQ is not supported, nor
+		 * can we support 2 levels of outer headers requiring
+		 * an update.
+		 */
+		if (!(tunnel->parms.o_flags & TUNNEL_CSUM) ||
+		    (tunnel->encap.type == TUNNEL_ENCAP_NONE)) {
+			dev->features    |= NETIF_F_GSO_SOFTWARE;
+			dev->hw_features |= NETIF_F_GSO_SOFTWARE;
+		}
+
 		/* Can use a lockless transmit, unless we generate
 		 * output sequences
 		 */
@@ -875,7 +890,7 @@ static int ipgre_tunnel_init(struct net_device *dev)
 	netif_keep_dst(dev);
 	dev->addr_len		= 4;
 
-	if (iph->daddr) {
+	if (iph->daddr && !tunnel->collect_md) {
 #ifdef CONFIG_NET_IPGRE_BROADCAST
 		if (ipv4_is_multicast(iph->daddr)) {
 			if (!iph->saddr)
@@ -884,8 +899,9 @@ static int ipgre_tunnel_init(struct net_device *dev)
 			dev->header_ops = &ipgre_header_ops;
 		}
 #endif
-	} else
+	} else if (!tunnel->collect_md) {
 		dev->header_ops = &ipgre_header_ops;
+	}
 
 	return ip_tunnel_init(dev);
 }
@@ -928,6 +944,11 @@ static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
 	if (flags & (GRE_VERSION|GRE_ROUTING))
 		return -EINVAL;
 
+	if (data[IFLA_GRE_COLLECT_METADATA] &&
+	    data[IFLA_GRE_ENCAP_TYPE] &&
+	    nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE)
+		return -EINVAL;
+
 	return 0;
 }
 
@@ -1001,6 +1022,8 @@ static void ipgre_netlink_parms(struct net_device *dev,
 		struct ip_tunnel *t = netdev_priv(dev);
 
 		t->collect_md = true;
+		if (dev->type == ARPHRD_IPGRE)
+			dev->type = ARPHRD_NONE;
 	}
 }
 
@@ -1230,6 +1253,7 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 {
 	struct nlattr *tb[IFLA_MAX + 1];
 	struct net_device *dev;
+	LIST_HEAD(list_kill);
 	struct ip_tunnel *t;
 	int err;
 
@@ -1245,8 +1269,10 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 	t->collect_md = true;
 
 	err = ipgre_newlink(net, dev, tb, NULL);
-	if (err < 0)
-		goto out;
+	if (err < 0) {
+		free_netdev(dev);
+		return ERR_PTR(err);
+	}
 
 	/* openvswitch users expect packet sizes to be unrestricted,
 	 * so set the largest MTU we can.
@@ -1255,9 +1281,14 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 	if (err)
 		goto out;
 
+	err = rtnl_configure_link(dev, NULL);
+	if (err < 0)
+		goto out;
+
 	return dev;
 out:
-	free_netdev(dev);
+	ip_tunnel_dellink(dev, &list_kill);
+	unregister_netdevice_many(&list_kill);
 	return ERR_PTR(err);
 }
 EXPORT_SYMBOL_GPL(gretap_fb_dev_create);