diff --git a/kernel/model/sync.go b/kernel/model/sync.go
index 62f72699b..1c122b6aa 100644
--- a/kernel/model/sync.go
+++ b/kernel/model/sync.go
@@ -69,6 +69,9 @@ func SyncData(boot, exit, byHand bool) {
 		return
 	}
 
+	syncLock.Lock()
+	defer syncLock.Unlock()
+
 	if boot {
 		util.IncBootProgress(3, "Syncing data from the cloud...")
 		BootSyncSucc = 0