diff --git a/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala b/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala
index c5f3f6e2b42b6..d88b25cc7e258 100644
--- a/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala
+++ b/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala
@@ -84,7 +84,7 @@ private[spark] class IndexShuffleBlockResolver(
    */
   private def checkIndexAndDataFile(index: File, data: File, blocks: Int): Array[Long] = {
     // the index file should have `block + 1` longs as offset.
-    if (index.length() != (blocks + 1) * 8) {
+    if (index.length() != (blocks + 1) * 8L) {
       return null
     }
     val lengths = new Array[Long](blocks)