diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 560f9571f7c4..37578d52897e 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -897,9 +897,9 @@ EXPORT_SYMBOL(tcp_md5_do_lookup);
 struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
 					 const struct sock *addr_sk)
 {
-	union tcp_md5_addr *addr;
+	const union tcp_md5_addr *addr;
 
-	addr = (union tcp_md5_addr *)&sk->sk_daddr;
+	addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr;
 	return tcp_md5_do_lookup(sk, addr, AF_INET);
 }
 EXPORT_SYMBOL(tcp_v4_md5_lookup);