diff --git a/infra/control/config.go b/infra/control/config.go
index 8fca11b0b..504975a8c 100644
--- a/infra/control/config.go
+++ b/infra/control/config.go
@@ -41,7 +41,9 @@ func (c *ConfigCommand) Execute(args []string) error {
 		r, err := c.LoadArg(arg)
 		common.Must(err)
 		c, err := serial.DecodeJSONConfig(r)
-		common.Must(err)
+		if err != nil {
+			ctllog.Fatalln(err)
+		}
 		conf.Override(c, arg)
 	}
 
diff --git a/main/main.go b/main/main.go
index 2d6f2f803..298e97d12 100644
--- a/main/main.go
+++ b/main/main.go
@@ -46,7 +46,9 @@ func readConfDir(dirPath string) {
 		log.Fatalln(err)
 	}
 	for _, f := range confs {
-		configFiles.Set(path.Join(dirPath, f.Name()))
+		if strings.HasSuffix(f.Name(), ".json") {
+			configFiles.Set(path.Join(dirPath, f.Name()))
+		}
 	}
 }