Merge branch 'seg6-fixes-to-Segment-Routing-in-IPv6'

Andrea Mayer says:

====================
seg6: fixes to Segment Routing in IPv6

This patchset is divided in 2 patches and it introduces some fixes
to Segment Routing in IPv6, which are:

- in function get_srh() fix the srh pointer after calling
  pskb_may_pull();

- fix the skb->transport_header after calling decap_and_validate()
  function;

Any comments on the patchset are welcome.
====================

Signed-off-by: David S. Miller <[email protected]>

Author: davem330

net/ipv6/seg6_local.c

@@ -81,6 +81,11 @@ static struct ipv6_sr_hdr *get_srh(struct sk_buff *skb)
 	if (!pskb_may_pull(skb, srhoff + len))
 		return NULL;
 
+	/* note that pskb_may_pull may change pointers in header;
+	 * for this reason it is necessary to reload them when needed.
+	 */
+	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+
 	if (!seg6_validate_srh(srh, len))
 		return NULL;
 
@@ -336,6 +341,8 @@ static int input_action_end_dx6(struct sk_buff *skb,
 	if (!ipv6_addr_any(&slwt->nh6))
 		nhaddr = &slwt->nh6;
 
+	skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+
 	seg6_lookup_nexthop(skb, nhaddr, 0);
 
 	return dst_input(skb);
@@ -365,6 +372,8 @@ static int input_action_end_dx4(struct sk_buff *skb,
 
 	skb_dst_drop(skb);
 
+	skb_set_transport_header(skb, sizeof(struct iphdr));
+
 	err = ip_route_input(skb, nhaddr, iph->saddr, 0, skb->dev);
 	if (err)
 		goto drop;
@@ -385,6 +394,8 @@ static int input_action_end_dt6(struct sk_buff *skb,
 	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 		goto drop;
 
+	skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+
 	seg6_lookup_nexthop(skb, NULL, slwt->table);
 
 	return dst_input(skb);