diff --git a/src/canonicalIdentityLock.js b/src/canonicalIdentityLock.js
index 236b9f2c..382e8d01 100644
--- a/src/canonicalIdentityLock.js
+++ b/src/canonicalIdentityLock.js
@@ -298,7 +298,7 @@ function prepareOwnerFile(lockDir, token) {
       mode: PRIVATE_FILE_MODE,
       flag: 'wx',
     });
-    descriptor = fs.openSync(preparedOwnerFile, 'r');
+    descriptor = fs.openSync(preparedOwnerFile, 'r+');
     fs.fdatasyncSync(descriptor);
     fs.closeSync(descriptor);
     descriptor = null;