JDK-8281000 ClassLoader::registerAsParallelCapable throws NPE if caller is null

make/test/JtregNativeJdk.gmk

@@ -62,6 +62,7 @@ ifeq ($(call isTargetOs, windows), true)
   WIN_LIB_JLI := $(SUPPORT_OUTPUTDIR)/native/java.base/libjli/jli.lib
   BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeJliLaunchTest := $(WIN_LIB_JLI)
   BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeCallerAccessTest := jvm.lib
+  BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeNullCallerClassLoaderTest := jvm.lib
   BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeNullCallerLookupTest := jvm.lib
   BUILD_JDK_JTREG_EXECUTABLES_LIBS_exerevokeall := advapi32.lib
   BUILD_JDK_JTREG_LIBRARIES_CFLAGS_libAsyncStackWalk := /EHsc
@@ -81,6 +82,7 @@ else
   endif
   BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeJliLaunchTest := -ljli
   BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeCallerAccessTest := -ljvm
+  BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeNullCallerClassLoaderTest := -ljvm
   BUILD_JDK_JTREG_EXECUTABLES_LIBS_exeNullCallerLookupTest := -ljvm
 endif
 

src/java.base/share/classes/java/lang/ClassLoader.java

@@ -1606,9 +1606,16 @@ protected Enumeration<URL> findResources(String name) throws IOException {
      * </ol>
      * <p>Note that once a class loader is registered as parallel capable, there
      * is no way to change it back.</p>
+     * <p>
+     * In cases where this method is called from a context where the caller is
+     * not a subclass of {@code ClassLoader} or there is no caller frame on the
+     * stack (e.g. when called directly from a JNI attached thread),
+     * {@code IllegalCallerException} is thrown.
+     * </p>
      *
      * @return  {@code true} if the caller is successfully registered as
      *          parallel capable and {@code false} if otherwise.
+     * @throws IllegalCallerException if the caller is not a subclass of {@code ClassLoader}
      *
      * @see #isRegisteredAsParallelCapable()
      *
@@ -1622,6 +1629,9 @@ protected static boolean registerAsParallelCapable() {
     // Caller-sensitive adapter method for reflective invocation
     @CallerSensitiveAdapter
     private static boolean registerAsParallelCapable(Class<?> caller) {
+        if ((caller == null) || !ClassLoader.class.isAssignableFrom(caller)) {
+            throw new IllegalCallerException(caller + " not a subclass of ClassLoader");
+        }
         return ParallelLoaders.register(caller.asSubclass(ClassLoader.class));
     }
 

test/jdk/java/lang/ClassLoader/BadRegisterAsParallelCapableCaller.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8281000
+ * @summary Test ClassLoader.isRegisteredAsParallelCapable() method with an
+ *   invalid caller (non-JNI cases).  This test uses reflection and opens
+ *   the java.base module so it runs separate from behavior tests of
+ *   isRegisteredParallelCapable to avoid side effects.
+ * @modules java.base/java.lang:open
+ * @run main/othervm BadRegisterAsParallelCapableCaller
+ */
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+public class BadRegisterAsParallelCapableCaller {
+
+    public static void main(String[] args) throws Exception {
+
+        Throwable thrown = null;
+        final Method m = ClassLoader.class.getDeclaredMethod("registerAsParallelCapable");
+        m.setAccessible(true);
+        try {
+            m.invoke(null);
+        } catch (InvocationTargetException ite) {
+            thrown = ite.getCause();
+        }
+        if (! (thrown instanceof IllegalCallerException)) {
+            throw new RuntimeException("Didn't get expected IllegalCallerException, got "+ thrown);
+        } else {
+            System.out.println("Invalid caller threw IllegalCallerException as expected");
+        }
+    }
+
+}

test/jdk/java/lang/ClassLoader/exeNullCallerClassLoaderTest/NullCallerClassLoaderTest.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+/**
+ * @test
+ * @bug 8281000
+ * @summary Test uses custom launcher that starts VM using JNI that verifies
+ *          ClassLoader.registerAsParallelCapable with null caller class
+ *          throws an IllegalCallerException.
+ * @library /test/lib
+ * @requires os.family != "aix"
+ * @run main/native NullCallerClassLoaderTest
+ */
+
+// Test disabled on AIX since we cannot invoke the JVM on the primordial thread.
+
+import java.io.File;
+import java.util.Map;
+import jdk.test.lib.Platform;
+import jdk.test.lib.process.OutputAnalyzer;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+public class NullCallerClassLoaderTest {
+    public static void main(String[] args) throws IOException {
+        Path launcher = Path.of(System.getProperty("test.nativepath"), "NullCallerClassLoaderTest");
+        ProcessBuilder pb = new ProcessBuilder(launcher.toString());
+        Map<String, String> env = pb.environment();
+
+        String libDir = Platform.libDir().toString();
+        String vmDir = Platform.jvmLibDir().toString();
+
+        // set up shared library path
+        String sharedLibraryPathEnvName = Platform.sharedLibraryPathVariableName();
+        env.compute(sharedLibraryPathEnvName,
+                (k, v) -> (v == null) ? libDir : v + File.pathSeparator + libDir);
+        env.compute(sharedLibraryPathEnvName,
+                (k, v) -> (v == null) ? vmDir : v + File.pathSeparator + vmDir);
+
+        System.out.println("Launching: " + launcher + " shared library path: " +
+                env.get(sharedLibraryPathEnvName));
+        new OutputAnalyzer(pb.start())
+                .outputTo(System.out)
+                .errorTo(System.err)
+                .shouldHaveExitValue(0);
+    }
+}
+

test/jdk/java/lang/ClassLoader/exeNullCallerClassLoaderTest/exeNullCallerClassLoaderTest.c

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "jni.h"
+#include "assert.h"
+
+static jclass class_IllegalCallerException;
+
+int checkAndClearIllegalCallerExceptionThrown(JNIEnv *env) {
+    jthrowable t = (*env)->ExceptionOccurred(env);
+    if ((*env)->IsInstanceOf(env, t, class_IllegalCallerException) == JNI_TRUE) {
+        (*env)->ExceptionClear(env);
+        return JNI_TRUE;
+    }
+    return JNI_FALSE;
+}
+
+int main(int argc, char** args) {
+    JavaVM *jvm;
+    JNIEnv *env;
+    JavaVMInitArgs vm_args;
+    JavaVMOption options[1];
+    jint rc;
+
+
+    vm_args.version = JNI_VERSION_1_2;
+    vm_args.nOptions = 0;
+    vm_args.options = options;
+
+    if ((rc = JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args)) != JNI_OK) {
+        printf("ERROR: cannot create VM.\n");
+        exit(-1);
+    }
+    class_IllegalCallerException = (*env)->FindClass(env, "java/lang/IllegalCallerException");
+    assert (class_IllegalCallerException != NULL);
+
+    // call ClassLoader.registerAsParallelCapable()
+    jclass class_ClassLoader = (*env)->FindClass(env, "java/lang/ClassLoader");
+    assert(class_ClassLoader != NULL);
+    jmethodID mid_ClassLoader_registerAsParallelCapable = (*env)->GetStaticMethodID(env, class_ClassLoader, "registerAsParallelCapable", "()Z" );
+    assert(mid_ClassLoader_registerAsParallelCapable != NULL);
+    jboolean b = (*env)->CallStaticBooleanMethod(env, class_ClassLoader, mid_ClassLoader_registerAsParallelCapable );
+    if ((rc = checkAndClearIllegalCallerExceptionThrown(env)) != JNI_TRUE) {
+        printf("ERROR: Didn't get the expected IllegalCallerException.\n");
+        exit(-1);
+    }
+
+    printf("Expected IllegalCallerException was thrown\n");
+
+    (*jvm)->DestroyJavaVM(jvm);
+    return 0;
+}
+