From: Ilan Tayari <ilant@mellanox.com>
Date: Tue, 1 Aug 2017 12:49:09 +0300
Subject: xfrm: Clear RX SKB secpath xfrm_offload
Patch-mainline: v4.14-rc1
Git-commit: 7e9e9202bccc3a8224ae10ad5d69cac8627f9c7b
References: bsc#1076830

If an incoming packet undergoes XFRM crypto-offload, its secpath is
filled with xfrm_offload struct denoting offload information.

If the SKB is then forwarded to a device which supports crypto-
offload, the stack wrongfully attempts to offload it (even though
the output SA may not exist on the device) due to the leftover
secpath xo.

Clear the ingress xo by zeroizing secpath->olen just before
delivering the decapsulated packet to the network stack.

Fixes: d77e38e612a0 ("xfrm: Add an IPsec hardware offloading API")
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Michal Kubecek <mkubecek@suse.cz>

---
 net/xfrm/xfrm_input.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index f2f7ad03cc3d..fc40de07fcc9 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -434,6 +434,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 	nf_reset(skb);
 
 	if (decaps) {
+		skb->sp->olen = 0;
 		skb_dst_drop(skb);
 		gro_cells_receive(&gro_cells, skb);
 		return 0;
@@ -444,6 +445,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 
 		err = x->inner_mode->afinfo->transport_finish(skb, xfrm_gro || async);
 		if (xfrm_gro) {
+			skb->sp->olen = 0;
 			skb_dst_drop(skb);
 			gro_cells_receive(&gro_cells, skb);
 			return err;
-- 
2.15.1