diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index b7635ef..cd7c46f 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1421,6 +1421,8 @@
 				       xfrm_address_t *saddr,
 				       unsigned short family,
 				       u8 mode, u8 proto, u32 reqid);
+struct xfrm_state *xfrm_state_lookup_byspi(struct net *net, __be32 spi,
+					      unsigned short family);
 int xfrm_state_check_expire(struct xfrm_state *x);
 void xfrm_state_insert(struct xfrm_state *x);
 int xfrm_state_add(struct xfrm_state *x);