--- old/src/share/classes/sun/misc/InnocuousThread.java Wed Jan 17 15:56:50 2018 +++ new/src/share/classes/sun/misc/InnocuousThread.java Wed Jan 17 15:56:50 2018 @@ -26,7 +26,10 @@ package sun.misc; import java.security.AccessControlContext; +import java.security.AccessController; import java.security.ProtectionDomain; +import java.security.PrivilegedAction; +import java.util.concurrent.atomic.AtomicInteger; /** * A thread that has no permissions, is not a member of any user-defined @@ -36,18 +39,47 @@ */ public final class InnocuousThread extends Thread { private static final Unsafe UNSAFE; - private static final ThreadGroup THREADGROUP; + private static final long THREAD_LOCALS; + private static final long INHERITABLE_THREAD_LOCALS; + private static final ThreadGroup INNOCUOUSTHREADGROUP; private static final AccessControlContext ACC; - private static final long THREADLOCALS; - private static final long INHERITABLETHREADLOCALS; private static final long INHERITEDACCESSCONTROLCONTEXT; + private static final long CONTEXTCLASSLOADER; + private static final AtomicInteger threadNumber = new AtomicInteger(1); + private static String newName() { + return "InnocuousThread-" + threadNumber.getAndIncrement(); + } + + /** + * Returns a new InnocuousThread with an auto-generated thread name. + * Its context class loader is set to null. + */ + public static Thread newSystemThread(Runnable target) { + return newSystemThread(newName(), target); + } + + /** + * Returns a new InnocuousThread with null context class loader. + */ + public static Thread newSystemThread(String name, Runnable target) { + return new InnocuousThread(INNOCUOUSTHREADGROUP, + target, name, null); + } + public InnocuousThread(Runnable target) { - super(THREADGROUP, target, "anInnocuousThread"); + super(INNOCUOUSTHREADGROUP, target, newName()); UNSAFE.putOrderedObject(this, INHERITEDACCESSCONTROLCONTEXT, ACC); eraseThreadLocals(); } + private InnocuousThread(ThreadGroup group, Runnable target, String name, ClassLoader tccl) { + super(group, target, name, 0L); + UNSAFE.putOrderedObject(this, INHERITEDACCESSCONTROLCONTEXT, ACC); + UNSAFE.putOrderedObject(this, CONTEXTCLASSLOADER, tccl); + eraseThreadLocals(); + } + @Override public ClassLoader getContextClassLoader() { // always report system class loader @@ -79,8 +111,8 @@ * Drops all thread locals (and inherited thread locals). */ public void eraseThreadLocals() { - UNSAFE.putObject(this, THREADLOCALS, null); - UNSAFE.putObject(this, INHERITABLETHREADLOCALS, null); + UNSAFE.putObject(this, THREAD_LOCALS, null); + UNSAFE.putObject(this, INHERITABLE_THREAD_LOCALS, null); } // Use Unsafe to access Thread group and ThreadGroup parent fields @@ -95,12 +127,14 @@ Class tk = Thread.class; Class gk = ThreadGroup.class; - THREADLOCALS = UNSAFE.objectFieldOffset + THREAD_LOCALS = UNSAFE.objectFieldOffset (tk.getDeclaredField("threadLocals")); - INHERITABLETHREADLOCALS = UNSAFE.objectFieldOffset + INHERITABLE_THREAD_LOCALS = UNSAFE.objectFieldOffset (tk.getDeclaredField("inheritableThreadLocals")); INHERITEDACCESSCONTROLCONTEXT = UNSAFE.objectFieldOffset (tk.getDeclaredField("inheritedAccessControlContext")); + CONTEXTCLASSLOADER = UNSAFE.objectFieldOffset + (tk.getDeclaredField("contextClassLoader")); long tg = UNSAFE.objectFieldOffset(tk.getDeclaredField("group")); long gp = UNSAFE.objectFieldOffset(gk.getDeclaredField("parent")); @@ -113,7 +147,14 @@ break; group = parent; } - THREADGROUP = new ThreadGroup(group, "InnocuousThreadGroup"); + final ThreadGroup root = group; + INNOCUOUSTHREADGROUP = AccessController.doPrivileged( + new PrivilegedAction() { + @Override + public ThreadGroup run() { + return new ThreadGroup(root, "InnocuousThreadGroup"); + } + }); } catch (Exception e) { throw new Error(e); }