diff --git a/core/src/main/scala/org/apache/spark/storage/DiskBlockManager.scala b/core/src/main/scala/org/apache/spark/storage/DiskBlockManager.scala
index e29f3fc1b805..a7ed9226c574 100644
--- a/core/src/main/scala/org/apache/spark/storage/DiskBlockManager.scala
+++ b/core/src/main/scala/org/apache/spark/storage/DiskBlockManager.scala
@@ -19,7 +19,7 @@ package org.apache.spark.storage
 
 import java.io.{File, IOException}
 import java.nio.file.Files
-import java.nio.file.attribute.PosixFilePermission
+import java.nio.file.attribute.{PosixFilePermission, PosixFilePermissions}
 import java.util.UUID
 
 import scala.collection.mutable.HashMap
@@ -301,9 +301,6 @@ private[spark] class DiskBlockManager(
    * Create a directory that is writable by the group.
    * Grant the permission 770 "rwxrwx---" to the directory so the shuffle server can
    * create subdirs/files within the merge folder.
-   * TODO: Find out why can't we create a dir using java api with permission 770
-   *  Files.createDirectories(mergeDir.toPath, PosixFilePermissions.asFileAttribute(
-   *  PosixFilePermissions.fromString("rwxrwx---")))
    */
   def createDirWithPermission770(dirToCreate: File): Unit = {
     var attempts = 0
@@ -315,16 +312,13 @@ private[spark] class DiskBlockManager(
         throw SparkCoreErrors.failToCreateDirectoryError(dirToCreate.getAbsolutePath, maxAttempts)
       }
       try {
-        val builder = new ProcessBuilder().command(
-          "mkdir", "-p", "-m770", dirToCreate.getAbsolutePath)
-        val proc = builder.start()
-        val exitCode = proc.waitFor()
+        dirToCreate.mkdirs()
+        Files.setPosixFilePermissions(
+          dirToCreate.toPath, PosixFilePermissions.fromString("rwxrwx---"))
         if (dirToCreate.exists()) {
           created = dirToCreate
         }
-        logDebug(
-          s"Created directory at ${dirToCreate.getAbsolutePath} with permission " +
-            s"770 and exitCode $exitCode")
+        logDebug(s"Created directory at ${dirToCreate.getAbsolutePath} with permission 770")
       } catch {
         case e: SecurityException =>
           logWarning(s"Failed to create directory ${dirToCreate.getAbsolutePath} " +