diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index 04805c7..434ef30 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -44,6 +44,7 @@
 {
 	struct dst_entry *dst = skb->dst;
 	struct xfrm_state *x = dst->xfrm;
+	struct iphdr *iph;
 	int err;
 
 	if (x->props.mode == XFRM_MODE_TUNNEL) {
@@ -56,6 +57,10 @@
 	if (err)
 		goto error_nolock;
 
+	iph = ip_hdr(skb);
+	iph->tot_len = htons(skb->len);
+	ip_send_check(iph);
+
 	IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
 	err = 0;