From 376056ca48fb5dbe3d57cea01a9fbf2ea4c35616 Mon Sep 17 00:00:00 2001 From: Aleksey Shipilev Date: Thu, 26 Sep 2024 15:14:21 +0000 Subject: [PATCH] 8336468: Reflection and MethodHandles should use more precise initializer checks Reviewed-by: liach, coleenp --- src/hotspot/share/classfile/javaClasses.cpp | 3 +- src/hotspot/share/prims/jni.cpp | 4 ++- src/hotspot/share/prims/jvm.cpp | 35 +++++++++++---------- src/hotspot/share/prims/methodHandles.cpp | 3 +- src/hotspot/share/runtime/reflection.cpp | 10 +++--- 5 files changed, 30 insertions(+), 25 deletions(-) diff --git a/src/hotspot/share/classfile/javaClasses.cpp b/src/hotspot/share/classfile/javaClasses.cpp index b6ef682ae0965..0ad36cd21dbf3 100644 --- a/src/hotspot/share/classfile/javaClasses.cpp +++ b/src/hotspot/share/classfile/javaClasses.cpp @@ -3052,9 +3052,10 @@ void java_lang_ClassFrameInfo::serialize_offsets(SerializeClosure* f) { static int get_flags(const methodHandle& m) { int flags = (jushort)( m->access_flags().as_short() & JVM_RECOGNIZED_METHOD_MODIFIERS ); - if (m->is_initializer()) { + if (m->is_object_initializer()) { flags |= java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR; } else { + // Note: Static initializers can be here. Record them as plain methods. flags |= java_lang_invoke_MemberName::MN_IS_METHOD; } if (m->caller_sensitive()) { diff --git a/src/hotspot/share/prims/jni.cpp b/src/hotspot/share/prims/jni.cpp index 1f115c783e6d7..a869e9821a0b2 100644 --- a/src/hotspot/share/prims/jni.cpp +++ b/src/hotspot/share/prims/jni.cpp @@ -444,9 +444,11 @@ JNI_ENTRY(jobject, jni_ToReflectedMethod(JNIEnv *env, jclass cls, jmethodID meth methodHandle m (THREAD, Method::resolve_jmethod_id(method_id)); assert(m->is_static() == (isStatic != 0), "jni_ToReflectedMethod access flags doesn't match"); oop reflection_method; - if (m->is_initializer()) { + if (m->is_object_initializer()) { reflection_method = Reflection::new_constructor(m, CHECK_NULL); } else { + // Note: Static initializers can theoretically be here, if JNI users manage + // to get their jmethodID. Record them as plain methods. reflection_method = Reflection::new_method(m, false, CHECK_NULL); } ret = JNIHandles::make_local(THREAD, reflection_method); diff --git a/src/hotspot/share/prims/jvm.cpp b/src/hotspot/share/prims/jvm.cpp index bf9874956bae2..a246c2c50d674 100644 --- a/src/hotspot/share/prims/jvm.cpp +++ b/src/hotspot/share/prims/jvm.cpp @@ -1826,14 +1826,6 @@ JVM_ENTRY(jobjectArray, JVM_GetRecordComponents(JNIEnv* env, jclass ofClass)) } JVM_END -static bool select_method(const methodHandle& method, bool want_constructor) { - if (want_constructor) { - return (method->is_initializer() && !method->is_static()); - } else { - return (!method->is_initializer() && !method->is_overpass()); - } -} - static jobjectArray get_class_declared_methods_helper( JNIEnv *env, jclass ofClass, jboolean publicOnly, @@ -1866,14 +1858,22 @@ static jobjectArray get_class_declared_methods_helper( GrowableArray* idnums = new GrowableArray(methods_length); int num_methods = 0; + // Select methods matching the criteria. for (int i = 0; i < methods_length; i++) { - methodHandle method(THREAD, methods->at(i)); - if (select_method(method, want_constructor)) { - if (!publicOnly || method->is_public()) { - idnums->push(method->method_idnum()); - ++num_methods; - } + Method* method = methods->at(i); + if (want_constructor && !method->is_object_initializer()) { + continue; + } + if (!want_constructor && + (method->is_object_initializer() || method->is_static_initializer() || + method->is_overpass())) { + continue; } + if (publicOnly && !method->is_public()) { + continue; + } + idnums->push(method->method_idnum()); + ++num_methods; } // Allocate result @@ -2175,10 +2175,11 @@ static jobject get_method_at_helper(const constantPoolHandle& cp, jint index, bo THROW_MSG_NULL(vmSymbols::java_lang_RuntimeException(), "Unable to look up method in target class"); } oop method; - if (!m->is_initializer() || m->is_static()) { - method = Reflection::new_method(m, true, CHECK_NULL); - } else { + if (m->is_object_initializer()) { method = Reflection::new_constructor(m, CHECK_NULL); + } else { + // new_method accepts as Method here + method = Reflection::new_method(m, true, CHECK_NULL); } return JNIHandles::make_local(THREAD, method); } diff --git a/src/hotspot/share/prims/methodHandles.cpp b/src/hotspot/share/prims/methodHandles.cpp index 4f33055d6a3fe..498da559cf526 100644 --- a/src/hotspot/share/prims/methodHandles.cpp +++ b/src/hotspot/share/prims/methodHandles.cpp @@ -313,8 +313,9 @@ oop MethodHandles::init_method_MemberName(Handle mname, CallInfo& info) { case CallInfo::direct_call: vmindex = Method::nonvirtual_vtable_index; if (m->is_static()) { + assert(!m->is_static_initializer(), "Cannot be static initializer"); flags |= IS_METHOD | (JVM_REF_invokeStatic << REFERENCE_KIND_SHIFT); - } else if (m->is_initializer()) { + } else if (m->is_object_initializer()) { flags |= IS_CONSTRUCTOR | (JVM_REF_invokeSpecial << REFERENCE_KIND_SHIFT); } else { // "special" reflects that this is a direct call, not that it diff --git a/src/hotspot/share/runtime/reflection.cpp b/src/hotspot/share/runtime/reflection.cpp index ab3d82ad7e2a4..15172b7f4c3d8 100644 --- a/src/hotspot/share/runtime/reflection.cpp +++ b/src/hotspot/share/runtime/reflection.cpp @@ -766,10 +766,10 @@ static Handle new_type(Symbol* signature, Klass* k, TRAPS) { } oop Reflection::new_method(const methodHandle& method, bool for_constant_pool_access, TRAPS) { - // Allow sun.reflect.ConstantPool to refer to methods as java.lang.reflect.Methods. - assert(!method()->is_initializer() || - (for_constant_pool_access && method()->is_static()), - "should call new_constructor instead"); + // Allow jdk.internal.reflect.ConstantPool to refer to methods as java.lang.reflect.Methods. + assert(!method()->is_object_initializer() && + (for_constant_pool_access || !method()->is_static_initializer()), + "Should not be the initializer"); InstanceKlass* holder = method->method_holder(); int slot = method->method_idnum(); @@ -817,7 +817,7 @@ oop Reflection::new_method(const methodHandle& method, bool for_constant_pool_ac oop Reflection::new_constructor(const methodHandle& method, TRAPS) { - assert(method()->is_initializer(), "should call new_method instead"); + assert(method()->is_object_initializer(), "Should be the initializer"); InstanceKlass* holder = method->method_holder(); int slot = method->method_idnum();