From: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Date: Mon, 3 Sep 2018 11:36:52 +0000 (-0700)
Subject: xfrm: reset transport header back to network header after all input transforms ahave... 
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bfc0698bebcb16d19ecfc89574ad4d696955e5d3;p=linux.git

xfrm: reset transport header back to network header after all input transforms ahave been applied

A policy may have been set up with multiple transforms (e.g., ESP
and ipcomp). In this situation, the ingress IPsec processing
iterates in xfrm_input() and applies each transform in turn,
processing the nexthdr to find any additional xfrm that may apply.

This patch resets the transport header back to network header
only after the last transformation so that subsequent xfrms
can find the correct transport header.

Fixes: 7785bba299a8 ("esp: Add a software GRO codepath")
Suggested-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---

diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index bcfc00e88756d..f8de2482a5292 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -67,6 +67,7 @@ int xfrm4_transport_finish(struct sk_buff *skb, int async)
 
 	if (xo && (xo->flags & XFRM_GRO)) {
 		skb_mac_header_rebuild(skb);
+		skb_reset_transport_header(skb);
 		return 0;
 	}
 
diff --git a/net/ipv4/xfrm4_mode_transport.c b/net/ipv4/xfrm4_mode_transport.c
index 3d36644890bb6..1ad2c2c4e250f 100644
--- a/net/ipv4/xfrm4_mode_transport.c
+++ b/net/ipv4/xfrm4_mode_transport.c
@@ -46,7 +46,6 @@ static int xfrm4_transport_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int ihl = skb->data - skb_transport_header(skb);
-	struct xfrm_offload *xo = xfrm_offload(skb);
 
 	if (skb->transport_header != skb->network_header) {
 		memmove(skb_transport_header(skb),
@@ -54,8 +53,7 @@ static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 		skb->network_header = skb->transport_header;
 	}
 	ip_hdr(skb)->tot_len = htons(skb->len + ihl);
-	if (!xo || !(xo->flags & XFRM_GRO))
-		skb_reset_transport_header(skb);
+	skb_reset_transport_header(skb);
 	return 0;
 }
 
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 841f4a07438e8..9ef490dddcea2 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -59,6 +59,7 @@ int xfrm6_transport_finish(struct sk_buff *skb, int async)
 
 	if (xo && (xo->flags & XFRM_GRO)) {
 		skb_mac_header_rebuild(skb);
+		skb_reset_transport_header(skb);
 		return -1;
 	}
 
diff --git a/net/ipv6/xfrm6_mode_transport.c b/net/ipv6/xfrm6_mode_transport.c
index 9ad07a91708ef..3c29da5defe6c 100644
--- a/net/ipv6/xfrm6_mode_transport.c
+++ b/net/ipv6/xfrm6_mode_transport.c
@@ -51,7 +51,6 @@ static int xfrm6_transport_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int ihl = skb->data - skb_transport_header(skb);
-	struct xfrm_offload *xo = xfrm_offload(skb);
 
 	if (skb->transport_header != skb->network_header) {
 		memmove(skb_transport_header(skb),
@@ -60,8 +59,7 @@ static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 	}
 	ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 					   sizeof(struct ipv6hdr));
-	if (!xo || !(xo->flags & XFRM_GRO))
-		skb_reset_transport_header(skb);
+	skb_reset_transport_header(skb);
 	return 0;
 }