4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>
[ Upstream commit b699d0035836f6712917a41e7ae58d84359b8ff9 ]
Since iptunnel_pull_header() can call pskb_may_pull(),
we must reload any pointer that was related to skb->head.
Fixes: a09a4c8dd1ec ("tunnels: Remove encapsulation offloads on decap")
Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv6/sit.c | 1 +
1 file changed, 1 insertion(+)
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -657,6 +657,7 @@ static int ipip6_rcv(struct sk_buff *skb
if (iptunnel_pull_header(skb, 0, htons(ETH_P_IPV6),
!net_eq(tunnel->net, dev_net(tunnel->dev))))
goto out;
+ iph = ip_hdr(skb);
err = IP_ECN_decapsulate(iph, skb);
if (unlikely(err)) {