diff --git a/interfaces/kits/js/src/mod_fs/properties/read_core.cpp b/interfaces/kits/js/src/mod_fs/properties/read_core.cpp
index 2099ebce63eb8ca42436d1a78e60305fc5247ad7..1c4ac55b94bc4102ff83ef22c206ed811d66ad26 100644
--- a/interfaces/kits/js/src/mod_fs/properties/read_core.cpp
+++ b/interfaces/kits/js/src/mod_fs/properties/read_core.cpp
@@ -34,12 +34,13 @@ static tuple<bool, void *, size_t, int64_t> ValidReadArg(ArrayBuffer &arrayBuffe
     int64_t offset = -1;
     bool succ = false;
     void *buf = arrayBuffer.buf;
-    size_t bufLen = arrayBuffer.length;
 
+    size_t bufLen = arrayBuffer.length;
     if (bufLen > UINT_MAX) {
         HILOGE("Invalid arraybuffer");
         return { false, nullptr, retLen, offset };
     }
+
     optional<size_t> lengthOp = nullopt;
     optional<int64_t> offsetOp = nullopt;
     if (options.has_value()) {