diff --git a/daemon/container.go b/daemon/container.go
index a972f8b712..da5745650c 100644
--- a/daemon/container.go
+++ b/daemon/container.go
@@ -102,13 +102,17 @@ func (container *Container) FromDisk() error {
 		return err
 	}
 
-	data, err := ioutil.ReadFile(pth)
+	jsonSource, err := os.Open(pth)
 	if err != nil {
 		return err
 	}
+	defer jsonSource.Close()
+
+	dec := json.NewDecoder(jsonSource)
+
 	// Load container settings
 	// udp broke compat of docker.PortMapping, but it's not used when loading a container, we can skip it
-	if err := json.Unmarshal(data, container); err != nil && !strings.Contains(err.Error(), "docker.PortMapping") {
+	if err := dec.Decode(container); err != nil && !strings.Contains(err.Error(), "docker.PortMapping") {
 		return err
 	}