Merge pull request #3978 from ChengJin01/access_check_interface_findS…

…pecial

Fix the access check in findSpecial

jcl/src/java.base/share/classes/java/lang/invoke/MethodHandles.java

@@ -549,12 +549,19 @@ private void checkClassAccess(Class<?> targetClass) throws IllegalAccessExceptio
 			throw new IllegalAccessException(com.ibm.oti.util.Msg.getString("K0680", accessClass.getName(), targetClass.getName()));  //$NON-NLS-1$
 		}
 
-		private void checkSpecialAccess(Class<?> callerClass) throws IllegalAccessException {
+		private void checkSpecialAccess(Class<?> declaringClass, Class<?> callerClass) throws IllegalAccessException {
 			if (INTERNAL_PRIVILEGED == accessMode) {
 				// Full access for use by MH implementation.
 				return;
 			}
-			if (isWeakenedLookup() || accessClass != callerClass) {
+			/* Given that findSpecial emulates the behavior of invokespecial,
+			 * calling interface methods of declaringClass should be allowed as long as 
+			 * declaringClass is an interface and callerClass can be assigned to it when
+			 * callerClass is not the same as the lookup class.
+			 */
+			if (isWeakenedLookup() 
+			|| ((accessClass != callerClass) && !(declaringClass.isInterface() && declaringClass.isAssignableFrom(callerClass)))
+			) {
 				/*[MSG "K0585", "{0} could not access {1} - private access required"]*/
 				throw new IllegalAccessException(com.ibm.oti.util.Msg.getString("K0585", accessClass.getName(), callerClass.getName())); //$NON-NLS-1$
 			}
@@ -580,12 +587,15 @@ private void checkSpecialAccess(Class<?> callerClass) throws IllegalAccessExcept
 		 */
 		public MethodHandle findSpecial(Class<?> clazz, String methodName, MethodType type, Class<?> specialToken) throws IllegalAccessException, NoSuchMethodException, SecurityException, NullPointerException {
 			nullCheck(clazz, methodName, type, specialToken);
-			checkSpecialAccess(specialToken);	/* Must happen before method resolution */
+			checkSpecialAccess(clazz, specialToken);	/* Must happen before method resolution */
 			MethodHandle handle = null;
 			try {
 				handle = findSpecialImpl(clazz, methodName, type, specialToken);
 				Class<?> handleDefc = handle.getDefc();
-				if ((handleDefc != accessClass) && !handleDefc.isAssignableFrom(accessClass)) {
+				/* Check the relationship between the lookup class and the current class
+				 * only when the requested caller class is the same as or subclass of the lookup class.
+				 */
+				if (accessClass.isAssignableFrom(specialToken) && !handleDefc.isAssignableFrom(accessClass)) {
 					/*[MSG "K0586", "Lookup class ({0}) must be the same as or subclass of the current class ({1})"]*/
 					throw new IllegalAccessException(com.ibm.oti.util.Msg.getString("K0586", accessClass, handleDefc)); //$NON-NLS-1$
 				}
@@ -1401,9 +1411,10 @@ public MethodHandle findConstructor(Class<?> declaringClass, MethodType type) th
 		 */
 		public MethodHandle unreflectSpecial(Method method, Class<?> specialToken) throws IllegalAccessException {
 			nullCheck(method, specialToken);
-			checkSpecialAccess(specialToken);	/* Must happen before method resolution */
+			Class<?> clazz = method.getDeclaringClass();
+			checkSpecialAccess(clazz, specialToken);	/* Must happen before method resolution */
 			String methodName = method.getName();
-			Map<CacheKey, WeakReference<MethodHandle>> cache = HandleCache.getSpecialCache(method.getDeclaringClass());
+			Map<CacheKey, WeakReference<MethodHandle>> cache = HandleCache.getSpecialCache(clazz);
 			MethodType type = MethodType.methodType(method.getReturnType(), method.getParameterTypes());
 			MethodHandle handle = HandleCache.getMethodWithSpecialCallerFromPerClassCache(cache, methodName, type, specialToken);
 			if (handle == null) {
@@ -1420,7 +1431,7 @@ public MethodHandle unreflectSpecial(Method method, Class<?> specialToken) throw
 			}
 
 			handle = SecurityFrameInjector.wrapHandleWithInjectedSecurityFrameIfRequired(this, handle);
-									
+
 			return handle;
 		}
 

test/functional/Jsr292/src/com/ibm/j9/jsr292/LookupAPITests_Find.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2001, 2018 IBM Corp. and others
+ * Copyright (c) 2001, 2019 IBM Corp. and others
  *
  * This program and the accompanying materials are made available under
  * the terms of the Eclipse Public License 2.0 which accompanies this
@@ -36,6 +36,7 @@
 import com.ibm.j9.jsr292.SamePackageExample.SamePackageInnerClass.SamePackageInnerClass_Nested_Level2;
 
 import examples.PackageExamples;
+import examples.CrossPackageDefaultMethodInterface;
 import examples.PackageExamples.CrossPackageInnerClass;
 
 /**
@@ -2098,6 +2099,33 @@ public void test_FindSpecial_Public_CrossPackage_InnerClass() throws Throwable {
 		AssertJUnit.assertEquals( 3, out );
 	}
 
+	/**
+	 * findSpecial test using a default method of an interface where the class (the resultant 
+	 * method handle will be bound to) is in a different package.
+	 * @throws Throwable
+	 */
+	@Test(groups = { "level.extended" })
+	public void test_FindSpecial_Default_CrossPackage_Interface() throws Throwable {
+		MethodHandle example = MethodHandles.lookup().findSpecial(CrossPackageDefaultMethodInterface.class, "addDefault", MethodType.methodType(int.class, int.class, int.class), CrossPackageDefaultMethodInterface.class);
+	}
+
+	/**
+	 * Negative findSpecial test using a public method of a class where the class (the resultant 
+	 * method handle will be bound to) is in a different package.
+	 * Note: when the lookup class is not equal to the caller class, the declaring class
+	 * must be an interface which the caller class can be assigned to.
+	 * @throws Throwable
+	 */
+	@Test(groups = { "level.extended" })
+	public void test_FindSpecial_Public_CrossPackage_Not_Interface() throws Throwable {
+		try {
+			MethodHandles.lookup().findSpecial(PackageExamples.class, "addPublic", MethodType.methodType(int.class, int.class, int.class), PackageExamples.class);
+			Assert.fail("No exception thrown finding a public method of a class in a different package");
+		} catch(IllegalAccessException e) {
+			// Exception expected, test passed
+		}
+	}
+
 	/**
 	 * Negative findSpecial test involving a private method 
 	 * @throws Throwable

test/functional/Jsr292/src/examples/CrossPackageDefaultMethodInterface.java

@@ -0,0 +1,35 @@
+/*******************************************************************************
+ * Copyright (c) 2019, 2019 IBM Corp. and others
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] http://openjdk.java.net/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
+ *******************************************************************************/
+package examples;
+
+/**
+ * Cross-package default method interface example used by LookupAPITests_Find 
+ * @author jincheng
+ *
+ */
+public interface CrossPackageDefaultMethodInterface {
+
+	default int addDefault(int a, int b) {
+		return (a + b);
+	}
+
+}