1 /* 2 * Copyright (C) 2021 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 import dalvik.system.PathClassLoader; 18 19 public class Main { 20 static String DEX_FILE = System.getenv("DEX_LOCATION") + "/833-background-verification.jar"; 21 static String DEX_FILE_EX = System.getenv("DEX_LOCATION") + "/833-background-verification-ex.jar"; 22 main(String[] args)23 public static void main(String[] args) throws Exception { 24 runTest(new UnknownLoader(DEX_FILE_EX)); 25 runTest(new PathClassLoader(DEX_FILE_EX, new UnknownLoader(DEX_FILE))); 26 } 27 runTest(ClassLoader loader)28 public static void runTest(ClassLoader loader) throws Exception { 29 // Use the class that will be verified the last by the background verifier. This maximises our 30 // chance of hitting the race. We load it now so that the background verifier can also load 31 // it. 32 Class<?> clsa = loader.loadClass("Classa"); 33 Class<?> cls1 = Class.forName("Class1", true, loader); 34 // Give some time for the background verification to verify "Classa". 35 Thread.sleep(1000); 36 clsa.newInstance(); 37 } 38 } 39 40 class UnknownLoader extends PathClassLoader { UnknownLoader(String dexFile)41 public UnknownLoader(String dexFile) { 42 super(dexFile, Object.class.getClassLoader()); 43 } 44 } 45