diff --git a/pkg/filemanager/driver/local/local.go b/pkg/filemanager/driver/local/local.go
index 3efb081e..33f6ea93 100644
--- a/pkg/filemanager/driver/local/local.go
+++ b/pkg/filemanager/driver/local/local.go
@@ -229,7 +229,9 @@ func (handler *Driver) Token(ctx context.Context, uploadSession *fs.UploadSessio
 	} else {
 		// When disk pre-allocation is disabled, concurrent chunk uploads must be 1
 		// to avoid disk fragmentation and write contention on local storage.
-		handler.Policy.Settings.ChunkConcurrency = 1
+ 		settings := *handler.Policy.Settings
+ 		settings.ChunkConcurrency = 1
+ 		handler.Policy.Settings = &settings
 	}
 
 	return &fs.UploadCredential{