Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

Steffen Klassert says:

====================
pull request (net): ipsec 2022-01-06

1) Fix xfrm policy lookups for ipv6 gre packets by initializing
   fl6_gre_key properly. From Ghalem Boudour.

2) Fix the dflt policy check on forwarding when there is no
   policy configured. The check was done for the wrong direction.
   From Nicolas Dichtel.

3) Use the correct 'struct xfrm_user_offload' when calculating
   netlink message lenghts in xfrm_sa_len(). From Eric Dumazet.

4) Tread inserting xfrm interface id 0 as an error.
   From Antony Antony.

5) Fail if xfrm state or policy is inserted with XFRMA_IF_ID 0,
   xfrm interfaces with id 0 are not allowed.
   From Antony Antony.

6) Fix inner_ipproto setting in the sec_path for tunnel mode.
   From  Raed Salem.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 25 insertions, 5 deletions

diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 229544bc70c2..4dc4a7bbe51c 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -647,10 +647,12 @@ static int xfrm_output_gso(struct net *net, struct sock *sk, struct sk_buff *skb
  * This requires hardware to know the inner packet type to calculate
  * the inner header checksum. Save inner ip protocol here to avoid
  * traversing the packet in the vendor's xmit code.
- * If the encap type is IPIP, just save skb->inner_ipproto. Otherwise,
- * get the ip protocol from the IP header.
+ * For IPsec tunnel mode save the ip protocol from the IP header of the
+ * plain text packet. Otherwise If the encap type is IPIP, just save
+ * skb->inner_ipproto in any other case get the ip protocol from the IP
+ * header.
  */
-static void xfrm_get_inner_ipproto(struct sk_buff *skb)
+static void xfrm_get_inner_ipproto(struct sk_buff *skb, struct xfrm_state *x)
 {
 	struct xfrm_offload *xo = xfrm_offload(skb);
 	const struct ethhdr *eth;
@@ -658,6 +660,25 @@ static void xfrm_get_inner_ipproto(struct sk_buff *skb)
 	if (!xo)
 		return;
 
+	if (x->outer_mode.encap == XFRM_MODE_TUNNEL) {
+		switch (x->outer_mode.family) {
+		case AF_INET:
+			xo->inner_ipproto = ip_hdr(skb)->protocol;
+			break;
+		case AF_INET6:
+			xo->inner_ipproto = ipv6_hdr(skb)->nexthdr;
+			break;
+		default:
+			break;
+		}
+
+		return;
+	}
+
+	/* non-Tunnel Mode */
+	if (!skb->encapsulation)
+		return;
+
 	if (skb->inner_protocol_type == ENCAP_TYPE_IPPROTO) {
 		xo->inner_ipproto = skb->inner_ipproto;
 		return;
@@ -712,8 +733,7 @@ int xfrm_output(struct sock *sk, struct sk_buff *skb)
 		sp->xvec[sp->len++] = x;
 		xfrm_state_hold(x);
 
-		if (skb->encapsulation)
-			xfrm_get_inner_ipproto(skb);
+		xfrm_get_inner_ipproto(skb, x);
 		skb->encapsulation = 1;
 
 		if (skb_is_gso(skb)) {