From: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>
[ Upstream commit 3bc817d665ac6d9de89f59df522ad86f5b5dfc03 ]
Since ip6_tnl_parse_tlv_enc_lim() can call pskb_may_pull()
which may change skb->data, so we need to re-load ipv6h at
the right place.
Fixes: 898b29798e36 ("ip6_gre: Refactor ip6gre xmit codes")
Cc: William Tu <u9012063@xxxxxxxxx>
Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>
Acked-by: William Tu <u9012063@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv6/ip6_gre.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -680,12 +680,13 @@ static int prepare_ip6gre_xmit_ipv6(stru
struct flowi6 *fl6, __u8 *dsfield,
int *encap_limit)
{
- struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+ struct ipv6hdr *ipv6h;
struct ip6_tnl *t = netdev_priv(dev);
__u16 offset;
offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
/* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
+ ipv6h = ipv6_hdr(skb);
if (offset > 0) {
struct ipv6_tlv_tnl_enc_lim *tel;
