diff --git a/tests/cts/net/src/android/net/cts/DscpPolicyTest.kt b/tests/cts/net/src/android/net/cts/DscpPolicyTest.kt
index 1f39fee..886b078 100644
--- a/tests/cts/net/src/android/net/cts/DscpPolicyTest.kt
+++ b/tests/cts/net/src/android/net/cts/DscpPolicyTest.kt
@@ -146,8 +146,9 @@
     fun tearDown() {
         agentsToCleanUp.forEach { it.unregister() }
         callbacksToCleanUp.forEach { cm.unregisterNetworkCallback(it) }
+
+        // reader.stop() cleans up tun fd
         reader.handler.post { reader.stop() }
-        Os.close(iface.fileDescriptor.fileDescriptor)
         handlerThread.quitSafely()
     }
 
@@ -519,4 +520,4 @@
 
 private fun <T> Context.assertHasService(manager: Class<T>): T {
     return getSystemService(manager) ?: fail("Service $manager not found")
-}
\ No newline at end of file
+}