diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 6ec6900eb300364bc908de8707b2a175abf04b77..a20e7f03d5f7d81ccf7e92de9bfbbcc3e2df6718 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -943,9 +943,9 @@ struct tcp_md5sig_key *tcp_md5_do_lookup(const struct sock *sk,
 }
 EXPORT_SYMBOL(tcp_md5_do_lookup);
 
-struct tcp_md5sig_key *tcp_md5_do_lookup_exact(const struct sock *sk,
-					       const union tcp_md5_addr *addr,
-					       int family, u8 prefixlen)
+static struct tcp_md5sig_key *tcp_md5_do_lookup_exact(const struct sock *sk,
+						      const union tcp_md5_addr *addr,
+						      int family, u8 prefixlen)
 {
 	const struct tcp_sock *tp = tcp_sk(sk);
 	struct tcp_md5sig_key *key;