1 // Copyright 2022 Code Intelligence GmbH 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package com.code_intelligence.jazzer.utils; 16 17 import java.lang.reflect.Field; 18 import java.util.Arrays; 19 import sun.misc.Unsafe; 20 21 public final class UnsafeProvider { 22 private static final Unsafe UNSAFE = getUnsafeInternal(); 23 getUnsafe()24 public static Unsafe getUnsafe() { 25 return UNSAFE; 26 } 27 getUnsafeInternal()28 private static Unsafe getUnsafeInternal() { 29 try { 30 // The Jazzer runtime is loaded by the bootstrap class loader and should thus pass the 31 // security checks in getUnsafe, so try that first. 32 return Unsafe.getUnsafe(); 33 } catch (Throwable unused) { 34 // If not running as an agent, use the classical reflection trick to get an Unsafe instance, 35 // taking into account that the private field may have a name other than "theUnsafe": 36 // https://android.googlesource.com/platform/libcore/+/gingerbread/luni/src/main/java/sun/misc/Unsafe.java#32 37 for (Field f : Unsafe.class.getDeclaredFields()) { 38 if (f.getType() == Unsafe.class) { 39 f.setAccessible(true); 40 try { 41 return (Unsafe) f.get(null); 42 } catch (IllegalAccessException e) { 43 throw new IllegalStateException( 44 "Please file a bug at https://github.com/CodeIntelligenceTesting/jazzer/issues/new " 45 + "with this information: Failed to access Unsafe member on Unsafe class", 46 e); 47 } 48 } 49 } 50 throw new IllegalStateException(String.format( 51 "Please file a bug at https://github.com/CodeIntelligenceTesting/jazzer/issues/new with " 52 + "this information: Failed to find Unsafe member on Unsafe class, have: " 53 + Arrays.deepToString(Unsafe.class.getDeclaredFields()))); 54 } 55 } 56 } 57