diff --git a/src/server.c b/src/server.c
index c96b096e2..326568041 100644
--- a/src/server.c
+++ b/src/server.c
@@ -4155,11 +4155,15 @@ static int cli_parse_set_server(char **args, struct appctx *appctx, void *privat
 			appctx->ctx.cli.severity = LOG_ERR;
 			appctx->ctx.cli.msg = "'set server <srv> check-port' expects an integer as argument.\n";
 			appctx->st0 = CLI_ST_PRINT;
+			SPIN_UNLOCK(SERVER_LOCK, &sv->lock);
+			return 1;
 		}
 		if ((i < 0) || (i > 65535)) {
 			appctx->ctx.cli.severity = LOG_ERR;
 			appctx->ctx.cli.msg = "provided port is not valid.\n";
 			appctx->st0 = CLI_ST_PRINT;
+			SPIN_UNLOCK(SERVER_LOCK, &sv->lock);
+			return 1;
 		}
 		/* prevent the update of port to 0 if MAPPORTS are in use */
 		if ((sv->flags & SRV_F_MAPPORTS) && (i == 0)) {