nfs_initialise_sb(sb);
 }
 
+/*
+ * If the user didn't specify a port, set the port number to
+ * the NFS version 4 default port.
+ */
+static void nfs4_default_port(struct sockaddr *sap)
+{
+       switch (sap->sa_family) {
+       case AF_INET: {
+               struct sockaddr_in *ap = (struct sockaddr_in *)sap;
+               if (ap->sin_port == 0)
+                       ap->sin_port = htons(NFS_PORT);
+               break;
+       }
+       case AF_INET6: {
+               struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
+               if (ap->sin6_port == 0)
+                       ap->sin6_port = htons(NFS_PORT);
+               break;
+       }
+       }
+}
+
 /*
  * Validate NFSv4 mount options
  */
                                   data->host_addr,
                                   sizeof(args->nfs_server.address)))
                        return -EFAULT;
-               if (args->nfs_server.address.sin_port == 0)
-                       args->nfs_server.address.sin_port = htons(NFS_PORT);
                if (!nfs_verify_server_address((struct sockaddr *)
                                                &args->nfs_server.address))
                        goto out_no_address;
 
+               nfs4_default_port((struct sockaddr *)
+                                 &args->nfs_server.address);
+
                switch (data->auth_flavourlen) {
                case 0:
                        args->auth_flavors[0] = RPC_AUTH_UNIX;
                if (nfs_parse_mount_options((char *)options, args) == 0)
                        return -EINVAL;
 
-               if (args->nfs_server.address.sin_port == 0)
-                       args->nfs_server.address.sin_port = htons(NFS_PORT);
                if (!nfs_verify_server_address((struct sockaddr *)
                                                &args->nfs_server.address))
                        return -EINVAL;
 
+               nfs4_default_port((struct sockaddr *)
+                                 &args->nfs_server.address);
+
                switch (args->auth_flavor_len) {
                case 0:
                        args->auth_flavors[0] = RPC_AUTH_UNIX;