| /* Copyright (C) 2016 The Android Open Source Project |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This file implements interfaces from the file jvmti.h. This implementation |
| * is licensed under the same terms as the file jvmti.h. The |
| * copyright and license information for the file jvmti.h follows. |
| * |
| * Copyright (c) 2003, 2011, 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * 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 "ti_redefine.h" |
| |
| #include <limits> |
| |
| #include "android-base/stringprintf.h" |
| |
| #include "art_jvmti.h" |
| #include "base/array_slice.h" |
| #include "base/logging.h" |
| #include "debugger.h" |
| #include "dex_file.h" |
| #include "dex_file_types.h" |
| #include "events-inl.h" |
| #include "gc/allocation_listener.h" |
| #include "gc/heap.h" |
| #include "instrumentation.h" |
| #include "jdwp/jdwp.h" |
| #include "jdwp/jdwp_constants.h" |
| #include "jdwp/jdwp_event.h" |
| #include "jdwp/object_registry.h" |
| #include "jit/jit.h" |
| #include "jit/jit_code_cache.h" |
| #include "jni_env_ext-inl.h" |
| #include "jvmti_allocator.h" |
| #include "mirror/class-inl.h" |
| #include "mirror/class_ext.h" |
| #include "mirror/object.h" |
| #include "non_debuggable_classes.h" |
| #include "object_lock.h" |
| #include "runtime.h" |
| #include "ScopedLocalRef.h" |
| #include "ti_class_loader.h" |
| #include "transform.h" |
| #include "verifier/method_verifier.h" |
| #include "verifier/verifier_log_mode.h" |
| |
| namespace openjdkjvmti { |
| |
| using android::base::StringPrintf; |
| |
| // A helper that fills in a classes obsolete_methods_ and obsolete_dex_caches_ classExt fields as |
| // they are created. This ensures that we can always call any method of an obsolete ArtMethod object |
| // almost as soon as they are created since the GetObsoleteDexCache method will succeed. |
| class ObsoleteMap { |
| public: |
| art::ArtMethod* FindObsoleteVersion(art::ArtMethod* original) |
| REQUIRES(art::Locks::mutator_lock_, art::Roles::uninterruptible_) { |
| auto method_pair = id_map_.find(original); |
| if (method_pair != id_map_.end()) { |
| art::ArtMethod* res = obsolete_methods_->GetElementPtrSize<art::ArtMethod*>( |
| method_pair->second, art::kRuntimePointerSize); |
| DCHECK(res != nullptr); |
| DCHECK_EQ(original, res->GetNonObsoleteMethod()); |
| return res; |
| } else { |
| return nullptr; |
| } |
| } |
| |
| void RecordObsolete(art::ArtMethod* original, art::ArtMethod* obsolete) |
| REQUIRES(art::Locks::mutator_lock_, art::Roles::uninterruptible_) { |
| DCHECK(original != nullptr); |
| DCHECK(obsolete != nullptr); |
| int32_t slot = next_free_slot_++; |
| DCHECK_LT(slot, obsolete_methods_->GetLength()); |
| DCHECK(nullptr == |
| obsolete_methods_->GetElementPtrSize<art::ArtMethod*>(slot, art::kRuntimePointerSize)); |
| DCHECK(nullptr == obsolete_dex_caches_->Get(slot)); |
| obsolete_methods_->SetElementPtrSize(slot, obsolete, art::kRuntimePointerSize); |
| obsolete_dex_caches_->Set(slot, original_dex_cache_); |
| id_map_.insert({original, slot}); |
| } |
| |
| ObsoleteMap(art::ObjPtr<art::mirror::PointerArray> obsolete_methods, |
| art::ObjPtr<art::mirror::ObjectArray<art::mirror::DexCache>> obsolete_dex_caches, |
| art::ObjPtr<art::mirror::DexCache> original_dex_cache) |
| : next_free_slot_(0), |
| obsolete_methods_(obsolete_methods), |
| obsolete_dex_caches_(obsolete_dex_caches), |
| original_dex_cache_(original_dex_cache) { |
| // Figure out where the first unused slot in the obsolete_methods_ array is. |
| while (obsolete_methods_->GetElementPtrSize<art::ArtMethod*>( |
| next_free_slot_, art::kRuntimePointerSize) != nullptr) { |
| DCHECK(obsolete_dex_caches_->Get(next_free_slot_) != nullptr); |
| next_free_slot_++; |
| } |
| // Sanity check that the same slot in obsolete_dex_caches_ is free. |
| DCHECK(obsolete_dex_caches_->Get(next_free_slot_) == nullptr); |
| } |
| |
| private: |
| int32_t next_free_slot_; |
| std::unordered_map<art::ArtMethod*, int32_t> id_map_; |
| // Pointers to the fields in mirror::ClassExt. These can be held as ObjPtr since this is only used |
| // when we have an exclusive mutator_lock_ (i.e. all threads are suspended). |
| art::ObjPtr<art::mirror::PointerArray> obsolete_methods_; |
| art::ObjPtr<art::mirror::ObjectArray<art::mirror::DexCache>> obsolete_dex_caches_; |
| art::ObjPtr<art::mirror::DexCache> original_dex_cache_; |
| }; |
| |
| // This visitor walks thread stacks and allocates and sets up the obsolete methods. It also does |
| // some basic sanity checks that the obsolete method is sane. |
| class ObsoleteMethodStackVisitor : public art::StackVisitor { |
| protected: |
| ObsoleteMethodStackVisitor( |
| art::Thread* thread, |
| art::LinearAlloc* allocator, |
| const std::unordered_set<art::ArtMethod*>& obsoleted_methods, |
| ObsoleteMap* obsolete_maps) |
| : StackVisitor(thread, |
| /*context*/nullptr, |
| StackVisitor::StackWalkKind::kIncludeInlinedFrames), |
| allocator_(allocator), |
| obsoleted_methods_(obsoleted_methods), |
| obsolete_maps_(obsolete_maps) { } |
| |
| ~ObsoleteMethodStackVisitor() OVERRIDE {} |
| |
| public: |
| // Returns true if we successfully installed obsolete methods on this thread, filling |
| // obsolete_maps_ with the translations if needed. Returns false and fills error_msg if we fail. |
| // The stack is cleaned up when we fail. |
| static void UpdateObsoleteFrames( |
| art::Thread* thread, |
| art::LinearAlloc* allocator, |
| const std::unordered_set<art::ArtMethod*>& obsoleted_methods, |
| ObsoleteMap* obsolete_maps) |
| REQUIRES(art::Locks::mutator_lock_) { |
| ObsoleteMethodStackVisitor visitor(thread, |
| allocator, |
| obsoleted_methods, |
| obsolete_maps); |
| visitor.WalkStack(); |
| } |
| |
| bool VisitFrame() OVERRIDE REQUIRES(art::Locks::mutator_lock_) { |
| art::ScopedAssertNoThreadSuspension snts("Fixing up the stack for obsolete methods."); |
| art::ArtMethod* old_method = GetMethod(); |
| if (obsoleted_methods_.find(old_method) != obsoleted_methods_.end()) { |
| // We cannot ensure that the right dex file is used in inlined frames so we don't support |
| // redefining them. |
| DCHECK(!IsInInlinedFrame()) << "Inlined frames are not supported when using redefinition"; |
| art::ArtMethod* new_obsolete_method = obsolete_maps_->FindObsoleteVersion(old_method); |
| if (new_obsolete_method == nullptr) { |
| // Create a new Obsolete Method and put it in the list. |
| art::Runtime* runtime = art::Runtime::Current(); |
| art::ClassLinker* cl = runtime->GetClassLinker(); |
| auto ptr_size = cl->GetImagePointerSize(); |
| const size_t method_size = art::ArtMethod::Size(ptr_size); |
| auto* method_storage = allocator_->Alloc(art::Thread::Current(), method_size); |
| CHECK(method_storage != nullptr) << "Unable to allocate storage for obsolete version of '" |
| << old_method->PrettyMethod() << "'"; |
| new_obsolete_method = new (method_storage) art::ArtMethod(); |
| new_obsolete_method->CopyFrom(old_method, ptr_size); |
| DCHECK_EQ(new_obsolete_method->GetDeclaringClass(), old_method->GetDeclaringClass()); |
| new_obsolete_method->SetIsObsolete(); |
| new_obsolete_method->SetDontCompile(); |
| obsolete_maps_->RecordObsolete(old_method, new_obsolete_method); |
| // Update JIT Data structures to point to the new method. |
| art::jit::Jit* jit = art::Runtime::Current()->GetJit(); |
| if (jit != nullptr) { |
| // Notify the JIT we are making this obsolete method. It will update the jit's internal |
| // structures to keep track of the new obsolete method. |
| jit->GetCodeCache()->MoveObsoleteMethod(old_method, new_obsolete_method); |
| } |
| } |
| DCHECK(new_obsolete_method != nullptr); |
| SetMethod(new_obsolete_method); |
| } |
| return true; |
| } |
| |
| private: |
| // The linear allocator we should use to make new methods. |
| art::LinearAlloc* allocator_; |
| // The set of all methods which could be obsoleted. |
| const std::unordered_set<art::ArtMethod*>& obsoleted_methods_; |
| // A map from the original to the newly allocated obsolete method for frames on this thread. The |
| // values in this map are added to the obsolete_methods_ (and obsolete_dex_caches_) fields of |
| // the redefined classes ClassExt as it is filled. |
| ObsoleteMap* obsolete_maps_; |
| }; |
| |
| jvmtiError Redefiner::IsModifiableClass(jvmtiEnv* env ATTRIBUTE_UNUSED, |
| jclass klass, |
| jboolean* is_redefinable) { |
| // TODO Check for the appropriate feature flags once we have enabled them. |
| art::Thread* self = art::Thread::Current(); |
| art::ScopedObjectAccess soa(self); |
| art::StackHandleScope<1> hs(self); |
| art::ObjPtr<art::mirror::Object> obj(self->DecodeJObject(klass)); |
| if (obj.IsNull()) { |
| return ERR(INVALID_CLASS); |
| } |
| art::Handle<art::mirror::Class> h_klass(hs.NewHandle(obj->AsClass())); |
| std::string err_unused; |
| *is_redefinable = |
| Redefiner::GetClassRedefinitionError(h_klass, &err_unused) == OK ? JNI_TRUE : JNI_FALSE; |
| return OK; |
| } |
| |
| jvmtiError Redefiner::GetClassRedefinitionError(art::Handle<art::mirror::Class> klass, |
| /*out*/std::string* error_msg) { |
| if (klass->IsPrimitive()) { |
| *error_msg = "Modification of primitive classes is not supported"; |
| return ERR(UNMODIFIABLE_CLASS); |
| } else if (klass->IsInterface()) { |
| *error_msg = "Modification of Interface classes is currently not supported"; |
| return ERR(UNMODIFIABLE_CLASS); |
| } else if (klass->IsStringClass()) { |
| *error_msg = "Modification of String class is not supported"; |
| return ERR(UNMODIFIABLE_CLASS); |
| } else if (klass->IsArrayClass()) { |
| *error_msg = "Modification of Array classes is not supported"; |
| return ERR(UNMODIFIABLE_CLASS); |
| } else if (klass->IsProxyClass()) { |
| *error_msg = "Modification of proxy classes is not supported"; |
| return ERR(UNMODIFIABLE_CLASS); |
| } |
| |
| for (jclass c : art::NonDebuggableClasses::GetNonDebuggableClasses()) { |
| if (klass.Get() == art::Thread::Current()->DecodeJObject(c)->AsClass()) { |
| *error_msg = "Class might have stack frames that cannot be made obsolete"; |
| return ERR(UNMODIFIABLE_CLASS); |
| } |
| } |
| |
| return OK; |
| } |
| |
| // Moves dex data to an anonymous, read-only mmap'd region. |
| std::unique_ptr<art::MemMap> Redefiner::MoveDataToMemMap(const std::string& original_location, |
| jint data_len, |
| const unsigned char* dex_data, |
| std::string* error_msg) { |
| std::unique_ptr<art::MemMap> map(art::MemMap::MapAnonymous( |
| StringPrintf("%s-transformed", original_location.c_str()).c_str(), |
| nullptr, |
| data_len, |
| PROT_READ|PROT_WRITE, |
| /*low_4gb*/false, |
| /*reuse*/false, |
| error_msg)); |
| if (map == nullptr) { |
| return map; |
| } |
| memcpy(map->Begin(), dex_data, data_len); |
| // Make the dex files mmap read only. This matches how other DexFiles are mmaped and prevents |
| // programs from corrupting it. |
| map->Protect(PROT_READ); |
| return map; |
| } |
| |
| Redefiner::ClassRedefinition::ClassRedefinition( |
| Redefiner* driver, |
| jclass klass, |
| const art::DexFile* redefined_dex_file, |
| const char* class_sig, |
| art::ArraySlice<const unsigned char> orig_dex_file) : |
| driver_(driver), |
| klass_(klass), |
| dex_file_(redefined_dex_file), |
| class_sig_(class_sig), |
| original_dex_file_(orig_dex_file) { |
| GetMirrorClass()->MonitorEnter(driver_->self_); |
| } |
| |
| Redefiner::ClassRedefinition::~ClassRedefinition() { |
| if (driver_ != nullptr) { |
| GetMirrorClass()->MonitorExit(driver_->self_); |
| } |
| } |
| |
| jvmtiError Redefiner::RedefineClasses(ArtJvmTiEnv* env, |
| EventHandler* event_handler, |
| art::Runtime* runtime, |
| art::Thread* self, |
| jint class_count, |
| const jvmtiClassDefinition* definitions, |
| /*out*/std::string* error_msg) { |
| if (env == nullptr) { |
| *error_msg = "env was null!"; |
| return ERR(INVALID_ENVIRONMENT); |
| } else if (class_count < 0) { |
| *error_msg = "class_count was less then 0"; |
| return ERR(ILLEGAL_ARGUMENT); |
| } else if (class_count == 0) { |
| // We don't actually need to do anything. Just return OK. |
| return OK; |
| } else if (definitions == nullptr) { |
| *error_msg = "null definitions!"; |
| return ERR(NULL_POINTER); |
| } |
| std::vector<ArtClassDefinition> def_vector; |
| def_vector.reserve(class_count); |
| for (jint i = 0; i < class_count; i++) { |
| jboolean is_modifiable = JNI_FALSE; |
| jvmtiError res = env->IsModifiableClass(definitions[i].klass, &is_modifiable); |
| if (res != OK) { |
| return res; |
| } else if (!is_modifiable) { |
| return ERR(UNMODIFIABLE_CLASS); |
| } |
| // We make a copy of the class_bytes to pass into the retransformation. |
| // This makes cleanup easier (since we unambiguously own the bytes) and also is useful since we |
| // will need to keep the original bytes around unaltered for subsequent RetransformClasses calls |
| // to get the passed in bytes. |
| unsigned char* class_bytes_copy = nullptr; |
| res = env->Allocate(definitions[i].class_byte_count, &class_bytes_copy); |
| if (res != OK) { |
| return res; |
| } |
| memcpy(class_bytes_copy, definitions[i].class_bytes, definitions[i].class_byte_count); |
| |
| ArtClassDefinition def; |
| def.dex_len = definitions[i].class_byte_count; |
| def.dex_data = MakeJvmtiUniquePtr(env, class_bytes_copy); |
| // We are definitely modified. |
| def.SetModified(); |
| def.original_dex_file = art::ArraySlice<const unsigned char>(definitions[i].class_bytes, |
| definitions[i].class_byte_count); |
| res = Transformer::FillInTransformationData(env, definitions[i].klass, &def); |
| if (res != OK) { |
| return res; |
| } |
| def_vector.push_back(std::move(def)); |
| } |
| // Call all the transformation events. |
| jvmtiError res = Transformer::RetransformClassesDirect(env, |
| event_handler, |
| self, |
| &def_vector); |
| if (res != OK) { |
| // Something went wrong with transformation! |
| return res; |
| } |
| return RedefineClassesDirect(env, runtime, self, def_vector, error_msg); |
| } |
| |
| jvmtiError Redefiner::RedefineClassesDirect(ArtJvmTiEnv* env, |
| art::Runtime* runtime, |
| art::Thread* self, |
| const std::vector<ArtClassDefinition>& definitions, |
| std::string* error_msg) { |
| DCHECK(env != nullptr); |
| if (definitions.size() == 0) { |
| // We don't actually need to do anything. Just return OK. |
| return OK; |
| } |
| // Stop JIT for the duration of this redefine since the JIT might concurrently compile a method we |
| // are going to redefine. |
| art::jit::ScopedJitSuspend suspend_jit; |
| // Get shared mutator lock so we can lock all the classes. |
| art::ScopedObjectAccess soa(self); |
| Redefiner r(runtime, self, error_msg); |
| for (const ArtClassDefinition& def : definitions) { |
| // Only try to transform classes that have been modified. |
| if (def.IsModified(self)) { |
| jvmtiError res = r.AddRedefinition(env, def); |
| if (res != OK) { |
| return res; |
| } |
| } |
| } |
| return r.Run(); |
| } |
| |
| jvmtiError Redefiner::AddRedefinition(ArtJvmTiEnv* env, const ArtClassDefinition& def) { |
| std::string original_dex_location; |
| jvmtiError ret = OK; |
| if ((ret = GetClassLocation(env, def.klass, &original_dex_location))) { |
| *error_msg_ = "Unable to get original dex file location!"; |
| return ret; |
| } |
| char* generic_ptr_unused = nullptr; |
| char* signature_ptr = nullptr; |
| if ((ret = env->GetClassSignature(def.klass, &signature_ptr, &generic_ptr_unused)) != OK) { |
| *error_msg_ = "Unable to get class signature!"; |
| return ret; |
| } |
| JvmtiUniquePtr<char> generic_unique_ptr(MakeJvmtiUniquePtr(env, generic_ptr_unused)); |
| JvmtiUniquePtr<char> signature_unique_ptr(MakeJvmtiUniquePtr(env, signature_ptr)); |
| std::unique_ptr<art::MemMap> map(MoveDataToMemMap(original_dex_location, |
| def.dex_len, |
| def.dex_data.get(), |
| error_msg_)); |
| std::ostringstream os; |
| if (map.get() == nullptr) { |
| os << "Failed to create anonymous mmap for modified dex file of class " << def.name |
| << "in dex file " << original_dex_location << " because: " << *error_msg_; |
| *error_msg_ = os.str(); |
| return ERR(OUT_OF_MEMORY); |
| } |
| if (map->Size() < sizeof(art::DexFile::Header)) { |
| *error_msg_ = "Could not read dex file header because dex_data was too short"; |
| return ERR(INVALID_CLASS_FORMAT); |
| } |
| uint32_t checksum = reinterpret_cast<const art::DexFile::Header*>(map->Begin())->checksum_; |
| std::unique_ptr<const art::DexFile> dex_file(art::DexFile::Open(map->GetName(), |
| checksum, |
| std::move(map), |
| /*verify*/true, |
| /*verify_checksum*/true, |
| error_msg_)); |
| if (dex_file.get() == nullptr) { |
| os << "Unable to load modified dex file for " << def.name << ": " << *error_msg_; |
| *error_msg_ = os.str(); |
| return ERR(INVALID_CLASS_FORMAT); |
| } |
| redefinitions_.push_back( |
| Redefiner::ClassRedefinition(this, |
| def.klass, |
| dex_file.release(), |
| signature_ptr, |
| def.original_dex_file)); |
| return OK; |
| } |
| |
| art::mirror::Class* Redefiner::ClassRedefinition::GetMirrorClass() { |
| return driver_->self_->DecodeJObject(klass_)->AsClass(); |
| } |
| |
| art::mirror::ClassLoader* Redefiner::ClassRedefinition::GetClassLoader() { |
| return GetMirrorClass()->GetClassLoader(); |
| } |
| |
| art::mirror::DexCache* Redefiner::ClassRedefinition::CreateNewDexCache( |
| art::Handle<art::mirror::ClassLoader> loader) { |
| return driver_->runtime_->GetClassLinker()->RegisterDexFile(*dex_file_, loader.Get()).Ptr(); |
| } |
| |
| void Redefiner::RecordFailure(jvmtiError result, |
| const std::string& class_sig, |
| const std::string& error_msg) { |
| *error_msg_ = StringPrintf("Unable to perform redefinition of '%s': %s", |
| class_sig.c_str(), |
| error_msg.c_str()); |
| result_ = result; |
| } |
| |
| art::mirror::ByteArray* Redefiner::ClassRedefinition::AllocateOrGetOriginalDexFileBytes() { |
| // If we have been specifically given a new set of bytes use that |
| if (original_dex_file_.size() != 0) { |
| return art::mirror::ByteArray::AllocateAndFill( |
| driver_->self_, |
| reinterpret_cast<const signed char*>(&original_dex_file_.At(0)), |
| original_dex_file_.size()); |
| } |
| |
| // See if we already have one set. |
| art::ObjPtr<art::mirror::ClassExt> ext(GetMirrorClass()->GetExtData()); |
| if (!ext.IsNull()) { |
| art::ObjPtr<art::mirror::ByteArray> old_original_bytes(ext->GetOriginalDexFileBytes()); |
| if (!old_original_bytes.IsNull()) { |
| // We do. Use it. |
| return old_original_bytes.Ptr(); |
| } |
| } |
| |
| // Copy the current dex_file |
| const art::DexFile& current_dex_file = GetMirrorClass()->GetDexFile(); |
| // TODO Handle this or make it so it cannot happen. |
| if (current_dex_file.NumClassDefs() != 1) { |
| LOG(WARNING) << "Current dex file has more than one class in it. Calling RetransformClasses " |
| << "on this class might fail if no transformations are applied to it!"; |
| } |
| return art::mirror::ByteArray::AllocateAndFill( |
| driver_->self_, |
| reinterpret_cast<const signed char*>(current_dex_file.Begin()), |
| current_dex_file.Size()); |
| } |
| |
| struct CallbackCtx { |
| ObsoleteMap* obsolete_map; |
| art::LinearAlloc* allocator; |
| std::unordered_set<art::ArtMethod*> obsolete_methods; |
| |
| explicit CallbackCtx(ObsoleteMap* map, art::LinearAlloc* alloc) |
| : obsolete_map(map), allocator(alloc) {} |
| }; |
| |
| void DoAllocateObsoleteMethodsCallback(art::Thread* t, void* vdata) NO_THREAD_SAFETY_ANALYSIS { |
| CallbackCtx* data = reinterpret_cast<CallbackCtx*>(vdata); |
| ObsoleteMethodStackVisitor::UpdateObsoleteFrames(t, |
| data->allocator, |
| data->obsolete_methods, |
| data->obsolete_map); |
| } |
| |
| // This creates any ArtMethod* structures needed for obsolete methods and ensures that the stack is |
| // updated so they will be run. |
| // TODO Rewrite so we can do this only once regardless of how many redefinitions there are. |
| void Redefiner::ClassRedefinition::FindAndAllocateObsoleteMethods(art::mirror::Class* art_klass) { |
| art::ScopedAssertNoThreadSuspension ns("No thread suspension during thread stack walking"); |
| art::mirror::ClassExt* ext = art_klass->GetExtData(); |
| CHECK(ext->GetObsoleteMethods() != nullptr); |
| art::ClassLinker* linker = driver_->runtime_->GetClassLinker(); |
| // This holds pointers to the obsolete methods map fields which are updated as needed. |
| ObsoleteMap map(ext->GetObsoleteMethods(), ext->GetObsoleteDexCaches(), art_klass->GetDexCache()); |
| CallbackCtx ctx(&map, linker->GetAllocatorForClassLoader(art_klass->GetClassLoader())); |
| // Add all the declared methods to the map |
| for (auto& m : art_klass->GetDeclaredMethods(art::kRuntimePointerSize)) { |
| if (m.IsIntrinsic()) { |
| LOG(WARNING) << "Redefining intrinsic method " << m.PrettyMethod() << ". This may cause the " |
| << "unexpected use of the original definition of " << m.PrettyMethod() << "in " |
| << "methods that have already been compiled."; |
| } |
| // It is possible to simply filter out some methods where they cannot really become obsolete, |
| // such as native methods and keep their original (possibly optimized) implementations. We don't |
| // do this, however, since we would need to mark these functions (still in the classes |
| // declared_methods array) as obsolete so we will find the correct dex file to get meta-data |
| // from (for example about stack-frame size). Furthermore we would be unable to get some useful |
| // error checking from the interpreter which ensure we don't try to start executing obsolete |
| // methods. |
| ctx.obsolete_methods.insert(&m); |
| } |
| { |
| art::MutexLock mu(driver_->self_, *art::Locks::thread_list_lock_); |
| art::ThreadList* list = art::Runtime::Current()->GetThreadList(); |
| list->ForEach(DoAllocateObsoleteMethodsCallback, static_cast<void*>(&ctx)); |
| } |
| } |
| |
| // Try and get the declared method. First try to get a virtual method then a direct method if that's |
| // not found. |
| static art::ArtMethod* FindMethod(art::Handle<art::mirror::Class> klass, |
| const char* name, |
| art::Signature sig) REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| art::ArtMethod* m = klass->FindDeclaredVirtualMethod(name, sig, art::kRuntimePointerSize); |
| if (m == nullptr) { |
| m = klass->FindDeclaredDirectMethod(name, sig, art::kRuntimePointerSize); |
| } |
| return m; |
| } |
| |
| bool Redefiner::ClassRedefinition::CheckSameMethods() { |
| art::StackHandleScope<1> hs(driver_->self_); |
| art::Handle<art::mirror::Class> h_klass(hs.NewHandle(GetMirrorClass())); |
| DCHECK_EQ(dex_file_->NumClassDefs(), 1u); |
| |
| art::ClassDataItemIterator new_iter(*dex_file_, |
| dex_file_->GetClassData(dex_file_->GetClassDef(0))); |
| |
| // Make sure we have the same number of methods. |
| uint32_t num_new_method = new_iter.NumVirtualMethods() + new_iter.NumDirectMethods(); |
| uint32_t num_old_method = h_klass->GetDeclaredMethodsSlice(art::kRuntimePointerSize).size(); |
| if (num_new_method != num_old_method) { |
| bool bigger = num_new_method > num_old_method; |
| RecordFailure(bigger ? ERR(UNSUPPORTED_REDEFINITION_METHOD_ADDED) |
| : ERR(UNSUPPORTED_REDEFINITION_METHOD_DELETED), |
| StringPrintf("Total number of declared methods changed from %d to %d", |
| num_old_method, num_new_method)); |
| return false; |
| } |
| |
| // Skip all of the fields. We should have already checked this. |
| while (new_iter.HasNextStaticField() || new_iter.HasNextInstanceField()) { |
| new_iter.Next(); |
| } |
| // Check each of the methods. NB we don't need to specifically check for removals since the 2 dex |
| // files have the same number of methods, which means there must be an equal amount of additions |
| // and removals. |
| for (; new_iter.HasNextVirtualMethod() || new_iter.HasNextDirectMethod(); new_iter.Next()) { |
| // Get the data on the method we are searching for |
| const art::DexFile::MethodId& new_method_id = dex_file_->GetMethodId(new_iter.GetMemberIndex()); |
| const char* new_method_name = dex_file_->GetMethodName(new_method_id); |
| art::Signature new_method_signature = dex_file_->GetMethodSignature(new_method_id); |
| art::ArtMethod* old_method = FindMethod(h_klass, new_method_name, new_method_signature); |
| // If we got past the check for the same number of methods above that means there must be at |
| // least one added and one removed method. We will return the ADDED failure message since it is |
| // easier to get a useful error report for it. |
| if (old_method == nullptr) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_METHOD_ADDED), |
| StringPrintf("Unknown method '%s' (sig: %s) was added!", |
| new_method_name, |
| new_method_signature.ToString().c_str())); |
| return false; |
| } |
| // Since direct methods have different flags than virtual ones (specifically direct methods must |
| // have kAccPrivate or kAccStatic or kAccConstructor flags) we can tell if a method changes from |
| // virtual to direct. |
| uint32_t new_flags = new_iter.GetMethodAccessFlags(); |
| if (new_flags != (old_method->GetAccessFlags() & art::kAccValidMethodFlags)) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_METHOD_MODIFIERS_CHANGED), |
| StringPrintf("method '%s' (sig: %s) had different access flags", |
| new_method_name, |
| new_method_signature.ToString().c_str())); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| bool Redefiner::ClassRedefinition::CheckSameFields() { |
| art::StackHandleScope<1> hs(driver_->self_); |
| art::Handle<art::mirror::Class> h_klass(hs.NewHandle(GetMirrorClass())); |
| DCHECK_EQ(dex_file_->NumClassDefs(), 1u); |
| art::ClassDataItemIterator new_iter(*dex_file_, |
| dex_file_->GetClassData(dex_file_->GetClassDef(0))); |
| const art::DexFile& old_dex_file = h_klass->GetDexFile(); |
| art::ClassDataItemIterator old_iter(old_dex_file, |
| old_dex_file.GetClassData(*h_klass->GetClassDef())); |
| // Instance and static fields can be differentiated by their flags so no need to check them |
| // separately. |
| while (new_iter.HasNextInstanceField() || new_iter.HasNextStaticField()) { |
| // Get the data on the method we are searching for |
| const art::DexFile::FieldId& new_field_id = dex_file_->GetFieldId(new_iter.GetMemberIndex()); |
| const char* new_field_name = dex_file_->GetFieldName(new_field_id); |
| const char* new_field_type = dex_file_->GetFieldTypeDescriptor(new_field_id); |
| |
| if (!(old_iter.HasNextInstanceField() || old_iter.HasNextStaticField())) { |
| // We are missing the old version of this method! |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_SCHEMA_CHANGED), |
| StringPrintf("Unknown field '%s' (type: %s) added!", |
| new_field_name, |
| new_field_type)); |
| return false; |
| } |
| |
| const art::DexFile::FieldId& old_field_id = old_dex_file.GetFieldId(old_iter.GetMemberIndex()); |
| const char* old_field_name = old_dex_file.GetFieldName(old_field_id); |
| const char* old_field_type = old_dex_file.GetFieldTypeDescriptor(old_field_id); |
| |
| // Check name and type. |
| if (strcmp(old_field_name, new_field_name) != 0 || |
| strcmp(old_field_type, new_field_type) != 0) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_SCHEMA_CHANGED), |
| StringPrintf("Field changed from '%s' (sig: %s) to '%s' (sig: %s)!", |
| old_field_name, |
| old_field_type, |
| new_field_name, |
| new_field_type)); |
| return false; |
| } |
| |
| // Since static fields have different flags than instance ones (specifically static fields must |
| // have the kAccStatic flag) we can tell if a field changes from static to instance. |
| if (new_iter.GetFieldAccessFlags() != old_iter.GetFieldAccessFlags()) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_SCHEMA_CHANGED), |
| StringPrintf("Field '%s' (sig: %s) had different access flags", |
| new_field_name, |
| new_field_type)); |
| return false; |
| } |
| |
| new_iter.Next(); |
| old_iter.Next(); |
| } |
| if (old_iter.HasNextInstanceField() || old_iter.HasNextStaticField()) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_SCHEMA_CHANGED), |
| StringPrintf("field '%s' (sig: %s) is missing!", |
| old_dex_file.GetFieldName(old_dex_file.GetFieldId( |
| old_iter.GetMemberIndex())), |
| old_dex_file.GetFieldTypeDescriptor(old_dex_file.GetFieldId( |
| old_iter.GetMemberIndex())))); |
| return false; |
| } |
| return true; |
| } |
| |
| bool Redefiner::ClassRedefinition::CheckClass() { |
| art::StackHandleScope<1> hs(driver_->self_); |
| // Easy check that only 1 class def is present. |
| if (dex_file_->NumClassDefs() != 1) { |
| RecordFailure(ERR(ILLEGAL_ARGUMENT), |
| StringPrintf("Expected 1 class def in dex file but found %d", |
| dex_file_->NumClassDefs())); |
| return false; |
| } |
| // Get the ClassDef from the new DexFile. |
| // Since the dex file has only a single class def the index is always 0. |
| const art::DexFile::ClassDef& def = dex_file_->GetClassDef(0); |
| // Get the class as it is now. |
| art::Handle<art::mirror::Class> current_class(hs.NewHandle(GetMirrorClass())); |
| |
| // Check the access flags didn't change. |
| if (def.GetJavaAccessFlags() != (current_class->GetAccessFlags() & art::kAccValidClassFlags)) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_CLASS_MODIFIERS_CHANGED), |
| "Cannot change modifiers of class by redefinition"); |
| return false; |
| } |
| |
| // Check class name. |
| // These should have been checked by the dexfile verifier on load. |
| DCHECK_NE(def.class_idx_, art::dex::TypeIndex::Invalid()) << "Invalid type index"; |
| const char* descriptor = dex_file_->StringByTypeIdx(def.class_idx_); |
| DCHECK(descriptor != nullptr) << "Invalid dex file structure!"; |
| if (!current_class->DescriptorEquals(descriptor)) { |
| std::string storage; |
| RecordFailure(ERR(NAMES_DONT_MATCH), |
| StringPrintf("expected file to contain class called '%s' but found '%s'!", |
| current_class->GetDescriptor(&storage), |
| descriptor)); |
| return false; |
| } |
| if (current_class->IsObjectClass()) { |
| if (def.superclass_idx_ != art::dex::TypeIndex::Invalid()) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Superclass added!"); |
| return false; |
| } |
| } else { |
| const char* super_descriptor = dex_file_->StringByTypeIdx(def.superclass_idx_); |
| DCHECK(descriptor != nullptr) << "Invalid dex file structure!"; |
| if (!current_class->GetSuperClass()->DescriptorEquals(super_descriptor)) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Superclass changed"); |
| return false; |
| } |
| } |
| const art::DexFile::TypeList* interfaces = dex_file_->GetInterfacesList(def); |
| if (interfaces == nullptr) { |
| if (current_class->NumDirectInterfaces() != 0) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Interfaces added"); |
| return false; |
| } |
| } else { |
| DCHECK(!current_class->IsProxyClass()); |
| const art::DexFile::TypeList* current_interfaces = current_class->GetInterfaceTypeList(); |
| if (current_interfaces == nullptr || current_interfaces->Size() != interfaces->Size()) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), "Interfaces added or removed"); |
| return false; |
| } |
| // The order of interfaces is (barely) meaningful so we error if it changes. |
| const art::DexFile& orig_dex_file = current_class->GetDexFile(); |
| for (uint32_t i = 0; i < interfaces->Size(); i++) { |
| if (strcmp( |
| dex_file_->StringByTypeIdx(interfaces->GetTypeItem(i).type_idx_), |
| orig_dex_file.StringByTypeIdx(current_interfaces->GetTypeItem(i).type_idx_)) != 0) { |
| RecordFailure(ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED), |
| "Interfaces changed or re-ordered"); |
| return false; |
| } |
| } |
| } |
| return true; |
| } |
| |
| bool Redefiner::ClassRedefinition::CheckRedefinable() { |
| std::string err; |
| art::StackHandleScope<1> hs(driver_->self_); |
| |
| art::Handle<art::mirror::Class> h_klass(hs.NewHandle(GetMirrorClass())); |
| jvmtiError res = Redefiner::GetClassRedefinitionError(h_klass, &err); |
| if (res != OK) { |
| RecordFailure(res, err); |
| return false; |
| } else { |
| return true; |
| } |
| } |
| |
| bool Redefiner::ClassRedefinition::CheckRedefinitionIsValid() { |
| return CheckRedefinable() && |
| CheckClass() && |
| CheckSameFields() && |
| CheckSameMethods(); |
| } |
| |
| class RedefinitionDataIter; |
| |
| // A wrapper that lets us hold onto the arbitrary sized data needed for redefinitions in a |
| // reasonably sane way. This adds no fields to the normal ObjectArray. By doing this we can avoid |
| // having to deal with the fact that we need to hold an arbitrary number of references live. |
| class RedefinitionDataHolder { |
| public: |
| enum DataSlot : int32_t { |
| kSlotSourceClassLoader = 0, |
| kSlotJavaDexFile = 1, |
| kSlotNewDexFileCookie = 2, |
| kSlotNewDexCache = 3, |
| kSlotMirrorClass = 4, |
| kSlotOrigDexFile = 5, |
| |
| // Must be last one. |
| kNumSlots = 6, |
| }; |
| |
| // This needs to have a HandleScope passed in that is capable of creating a new Handle without |
| // overflowing. Only one handle will be created. This object has a lifetime identical to that of |
| // the passed in handle-scope. |
| RedefinitionDataHolder(art::StackHandleScope<1>* hs, |
| art::Runtime* runtime, |
| art::Thread* self, |
| std::vector<Redefiner::ClassRedefinition>* redefinitions) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) : |
| arr_( |
| hs->NewHandle( |
| art::mirror::ObjectArray<art::mirror::Object>::Alloc( |
| self, |
| runtime->GetClassLinker()->GetClassRoot(art::ClassLinker::kObjectArrayClass), |
| redefinitions->size() * kNumSlots))), |
| redefinitions_(redefinitions) {} |
| |
| bool IsNull() const REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return arr_.IsNull(); |
| } |
| |
| // TODO Maybe make an iterable view type to simplify using this. |
| art::mirror::ClassLoader* GetSourceClassLoader(jint klass_index) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return art::down_cast<art::mirror::ClassLoader*>(GetSlot(klass_index, kSlotSourceClassLoader)); |
| } |
| art::mirror::Object* GetJavaDexFile(jint klass_index) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return GetSlot(klass_index, kSlotJavaDexFile); |
| } |
| art::mirror::LongArray* GetNewDexFileCookie(jint klass_index) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return art::down_cast<art::mirror::LongArray*>(GetSlot(klass_index, kSlotNewDexFileCookie)); |
| } |
| art::mirror::DexCache* GetNewDexCache(jint klass_index) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return art::down_cast<art::mirror::DexCache*>(GetSlot(klass_index, kSlotNewDexCache)); |
| } |
| art::mirror::Class* GetMirrorClass(jint klass_index) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return art::down_cast<art::mirror::Class*>(GetSlot(klass_index, kSlotMirrorClass)); |
| } |
| |
| art::mirror::ByteArray* GetOriginalDexFileBytes(jint klass_index) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return art::down_cast<art::mirror::ByteArray*>(GetSlot(klass_index, kSlotOrigDexFile)); |
| } |
| |
| void SetSourceClassLoader(jint klass_index, art::mirror::ClassLoader* loader) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| SetSlot(klass_index, kSlotSourceClassLoader, loader); |
| } |
| void SetJavaDexFile(jint klass_index, art::mirror::Object* dexfile) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| SetSlot(klass_index, kSlotJavaDexFile, dexfile); |
| } |
| void SetNewDexFileCookie(jint klass_index, art::mirror::LongArray* cookie) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| SetSlot(klass_index, kSlotNewDexFileCookie, cookie); |
| } |
| void SetNewDexCache(jint klass_index, art::mirror::DexCache* cache) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| SetSlot(klass_index, kSlotNewDexCache, cache); |
| } |
| void SetMirrorClass(jint klass_index, art::mirror::Class* klass) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| SetSlot(klass_index, kSlotMirrorClass, klass); |
| } |
| void SetOriginalDexFileBytes(jint klass_index, art::mirror::ByteArray* bytes) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| SetSlot(klass_index, kSlotOrigDexFile, bytes); |
| } |
| |
| int32_t Length() const REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return arr_->GetLength() / kNumSlots; |
| } |
| |
| std::vector<Redefiner::ClassRedefinition>* GetRedefinitions() |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return redefinitions_; |
| } |
| |
| bool operator==(const RedefinitionDataHolder& other) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return arr_.Get() == other.arr_.Get(); |
| } |
| |
| bool operator!=(const RedefinitionDataHolder& other) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return !(*this == other); |
| } |
| |
| RedefinitionDataIter begin() REQUIRES_SHARED(art::Locks::mutator_lock_); |
| RedefinitionDataIter end() REQUIRES_SHARED(art::Locks::mutator_lock_); |
| |
| private: |
| mutable art::Handle<art::mirror::ObjectArray<art::mirror::Object>> arr_; |
| std::vector<Redefiner::ClassRedefinition>* redefinitions_; |
| |
| art::mirror::Object* GetSlot(jint klass_index, |
| DataSlot slot) const REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| DCHECK_LT(klass_index, Length()); |
| return arr_->Get((kNumSlots * klass_index) + slot); |
| } |
| |
| void SetSlot(jint klass_index, |
| DataSlot slot, |
| art::ObjPtr<art::mirror::Object> obj) REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| DCHECK(!art::Runtime::Current()->IsActiveTransaction()); |
| DCHECK_LT(klass_index, Length()); |
| arr_->Set<false>((kNumSlots * klass_index) + slot, obj); |
| } |
| |
| DISALLOW_COPY_AND_ASSIGN(RedefinitionDataHolder); |
| }; |
| |
| class RedefinitionDataIter { |
| public: |
| RedefinitionDataIter(int32_t idx, RedefinitionDataHolder& holder) : idx_(idx), holder_(holder) {} |
| |
| RedefinitionDataIter(const RedefinitionDataIter&) = default; |
| RedefinitionDataIter(RedefinitionDataIter&&) = default; |
| RedefinitionDataIter& operator=(const RedefinitionDataIter&) = default; |
| RedefinitionDataIter& operator=(RedefinitionDataIter&&) = default; |
| |
| bool operator==(const RedefinitionDataIter& other) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return idx_ == other.idx_ && holder_ == other.holder_; |
| } |
| |
| bool operator!=(const RedefinitionDataIter& other) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return !(*this == other); |
| } |
| |
| RedefinitionDataIter operator++() { // Value after modification. |
| idx_++; |
| return *this; |
| } |
| |
| RedefinitionDataIter operator++(int) { |
| RedefinitionDataIter temp = *this; |
| idx_++; |
| return temp; |
| } |
| |
| RedefinitionDataIter operator+(ssize_t delta) const { |
| RedefinitionDataIter temp = *this; |
| temp += delta; |
| return temp; |
| } |
| |
| RedefinitionDataIter& operator+=(ssize_t delta) { |
| idx_ += delta; |
| return *this; |
| } |
| |
| Redefiner::ClassRedefinition& GetRedefinition() REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return (*holder_.GetRedefinitions())[idx_]; |
| } |
| |
| RedefinitionDataHolder& GetHolder() { |
| return holder_; |
| } |
| |
| art::mirror::ClassLoader* GetSourceClassLoader() const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return holder_.GetSourceClassLoader(idx_); |
| } |
| art::mirror::Object* GetJavaDexFile() const REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return holder_.GetJavaDexFile(idx_); |
| } |
| art::mirror::LongArray* GetNewDexFileCookie() const REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return holder_.GetNewDexFileCookie(idx_); |
| } |
| art::mirror::DexCache* GetNewDexCache() const REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return holder_.GetNewDexCache(idx_); |
| } |
| art::mirror::Class* GetMirrorClass() const REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return holder_.GetMirrorClass(idx_); |
| } |
| art::mirror::ByteArray* GetOriginalDexFileBytes() const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| return holder_.GetOriginalDexFileBytes(idx_); |
| } |
| int32_t GetIndex() const { |
| return idx_; |
| } |
| |
| void SetSourceClassLoader(art::mirror::ClassLoader* loader) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| holder_.SetSourceClassLoader(idx_, loader); |
| } |
| void SetJavaDexFile(art::mirror::Object* dexfile) REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| holder_.SetJavaDexFile(idx_, dexfile); |
| } |
| void SetNewDexFileCookie(art::mirror::LongArray* cookie) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| holder_.SetNewDexFileCookie(idx_, cookie); |
| } |
| void SetNewDexCache(art::mirror::DexCache* cache) REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| holder_.SetNewDexCache(idx_, cache); |
| } |
| void SetMirrorClass(art::mirror::Class* klass) REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| holder_.SetMirrorClass(idx_, klass); |
| } |
| void SetOriginalDexFileBytes(art::mirror::ByteArray* bytes) |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| holder_.SetOriginalDexFileBytes(idx_, bytes); |
| } |
| |
| private: |
| int32_t idx_; |
| RedefinitionDataHolder& holder_; |
| }; |
| |
| RedefinitionDataIter RedefinitionDataHolder::begin() { |
| return RedefinitionDataIter(0, *this); |
| } |
| |
| RedefinitionDataIter RedefinitionDataHolder::end() { |
| return RedefinitionDataIter(Length(), *this); |
| } |
| |
| bool Redefiner::ClassRedefinition::CheckVerification(const RedefinitionDataIter& iter) { |
| DCHECK_EQ(dex_file_->NumClassDefs(), 1u); |
| art::StackHandleScope<2> hs(driver_->self_); |
| std::string error; |
| // TODO Make verification log level lower |
| art::verifier::MethodVerifier::FailureKind failure = |
| art::verifier::MethodVerifier::VerifyClass(driver_->self_, |
| dex_file_.get(), |
| hs.NewHandle(iter.GetNewDexCache()), |
| hs.NewHandle(GetClassLoader()), |
| dex_file_->GetClassDef(0), /*class_def*/ |
| nullptr, /*compiler_callbacks*/ |
| false, /*allow_soft_failures*/ |
| /*log_level*/ |
| art::verifier::HardFailLogMode::kLogWarning, |
| &error); |
| bool passes = failure == art::verifier::MethodVerifier::kNoFailure; |
| if (!passes) { |
| RecordFailure(ERR(FAILS_VERIFICATION), "Failed to verify class. Error was: " + error); |
| } |
| return passes; |
| } |
| |
| // Looks through the previously allocated cookies to see if we need to update them with another new |
| // dexfile. This is so that even if multiple classes with the same classloader are redefined at |
| // once they are all added to the classloader. |
| bool Redefiner::ClassRedefinition::AllocateAndRememberNewDexFileCookie( |
| art::Handle<art::mirror::ClassLoader> source_class_loader, |
| art::Handle<art::mirror::Object> dex_file_obj, |
| /*out*/RedefinitionDataIter* cur_data) { |
| art::StackHandleScope<2> hs(driver_->self_); |
| art::MutableHandle<art::mirror::LongArray> old_cookie( |
| hs.NewHandle<art::mirror::LongArray>(nullptr)); |
| bool has_older_cookie = false; |
| // See if we already have a cookie that a previous redefinition got from the same classloader. |
| for (auto old_data = cur_data->GetHolder().begin(); old_data != *cur_data; ++old_data) { |
| if (old_data.GetSourceClassLoader() == source_class_loader.Get()) { |
| // Since every instance of this classloader should have the same cookie associated with it we |
| // can stop looking here. |
| has_older_cookie = true; |
| old_cookie.Assign(old_data.GetNewDexFileCookie()); |
| break; |
| } |
| } |
| if (old_cookie.IsNull()) { |
| // No older cookie. Get it directly from the dex_file_obj |
| // We should not have seen this classloader elsewhere. |
| CHECK(!has_older_cookie); |
| old_cookie.Assign(ClassLoaderHelper::GetDexFileCookie(dex_file_obj)); |
| } |
| // Use the old cookie to generate the new one with the new DexFile* added in. |
| art::Handle<art::mirror::LongArray> |
| new_cookie(hs.NewHandle(ClassLoaderHelper::AllocateNewDexFileCookie(driver_->self_, |
| old_cookie, |
| dex_file_.get()))); |
| // Make sure the allocation worked. |
| if (new_cookie.IsNull()) { |
| return false; |
| } |
| |
| // Save the cookie. |
| cur_data->SetNewDexFileCookie(new_cookie.Get()); |
| // If there are other copies of this same classloader we need to make sure that we all have the |
| // same cookie. |
| if (has_older_cookie) { |
| for (auto old_data = cur_data->GetHolder().begin(); old_data != *cur_data; ++old_data) { |
| // We will let the GC take care of the cookie we allocated for this one. |
| if (old_data.GetSourceClassLoader() == source_class_loader.Get()) { |
| old_data.SetNewDexFileCookie(new_cookie.Get()); |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| bool Redefiner::ClassRedefinition::FinishRemainingAllocations( |
| /*out*/RedefinitionDataIter* cur_data) { |
| art::ScopedObjectAccessUnchecked soa(driver_->self_); |
| art::StackHandleScope<2> hs(driver_->self_); |
| cur_data->SetMirrorClass(GetMirrorClass()); |
| // This shouldn't allocate |
| art::Handle<art::mirror::ClassLoader> loader(hs.NewHandle(GetClassLoader())); |
| // The bootclasspath is handled specially so it doesn't have a j.l.DexFile. |
| if (!art::ClassLinker::IsBootClassLoader(soa, loader.Get())) { |
| cur_data->SetSourceClassLoader(loader.Get()); |
| art::Handle<art::mirror::Object> dex_file_obj(hs.NewHandle( |
| ClassLoaderHelper::FindSourceDexFileObject(driver_->self_, loader))); |
| cur_data->SetJavaDexFile(dex_file_obj.Get()); |
| if (dex_file_obj == nullptr) { |
| RecordFailure(ERR(INTERNAL), "Unable to find dex file!"); |
| return false; |
| } |
| // Allocate the new dex file cookie. |
| if (!AllocateAndRememberNewDexFileCookie(loader, dex_file_obj, cur_data)) { |
| driver_->self_->AssertPendingOOMException(); |
| driver_->self_->ClearException(); |
| RecordFailure(ERR(OUT_OF_MEMORY), "Unable to allocate dex file array for class loader"); |
| return false; |
| } |
| } |
| cur_data->SetNewDexCache(CreateNewDexCache(loader)); |
| if (cur_data->GetNewDexCache() == nullptr) { |
| driver_->self_->AssertPendingException(); |
| driver_->self_->ClearException(); |
| RecordFailure(ERR(OUT_OF_MEMORY), "Unable to allocate DexCache"); |
| return false; |
| } |
| |
| // We won't always need to set this field. |
| cur_data->SetOriginalDexFileBytes(AllocateOrGetOriginalDexFileBytes()); |
| if (cur_data->GetOriginalDexFileBytes() == nullptr) { |
| driver_->self_->AssertPendingOOMException(); |
| driver_->self_->ClearException(); |
| RecordFailure(ERR(OUT_OF_MEMORY), "Unable to allocate array for original dex file"); |
| return false; |
| } |
| return true; |
| } |
| |
| void Redefiner::ClassRedefinition::UnregisterBreakpoints() { |
| DCHECK(art::Dbg::IsDebuggerActive()); |
| art::JDWP::JdwpState* state = art::Dbg::GetJdwpState(); |
| if (state != nullptr) { |
| state->UnregisterLocationEventsOnClass(GetMirrorClass()); |
| } |
| } |
| |
| void Redefiner::UnregisterAllBreakpoints() { |
| if (LIKELY(!art::Dbg::IsDebuggerActive())) { |
| return; |
| } |
| for (Redefiner::ClassRedefinition& redef : redefinitions_) { |
| redef.UnregisterBreakpoints(); |
| } |
| } |
| |
| bool Redefiner::CheckAllRedefinitionAreValid() { |
| for (Redefiner::ClassRedefinition& redef : redefinitions_) { |
| if (!redef.CheckRedefinitionIsValid()) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| bool Redefiner::EnsureAllClassAllocationsFinished() { |
| for (Redefiner::ClassRedefinition& redef : redefinitions_) { |
| if (!redef.EnsureClassAllocationsFinished()) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| bool Redefiner::FinishAllRemainingAllocations(RedefinitionDataHolder& holder) { |
| for (RedefinitionDataIter data = holder.begin(); data != holder.end(); ++data) { |
| // Allocate the data this redefinition requires. |
| if (!data.GetRedefinition().FinishRemainingAllocations(&data)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| void Redefiner::ClassRedefinition::ReleaseDexFile() { |
| dex_file_.release(); |
| } |
| |
| void Redefiner::ReleaseAllDexFiles() { |
| for (Redefiner::ClassRedefinition& redef : redefinitions_) { |
| redef.ReleaseDexFile(); |
| } |
| } |
| |
| bool Redefiner::CheckAllClassesAreVerified(RedefinitionDataHolder& holder) { |
| for (RedefinitionDataIter data = holder.begin(); data != holder.end(); ++data) { |
| if (!data.GetRedefinition().CheckVerification(data)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| class ScopedDisableConcurrentAndMovingGc { |
| public: |
| ScopedDisableConcurrentAndMovingGc(art::gc::Heap* heap, art::Thread* self) |
| : heap_(heap), self_(self) { |
| if (heap_->IsGcConcurrentAndMoving()) { |
| heap_->IncrementDisableMovingGC(self_); |
| } |
| } |
| |
| ~ScopedDisableConcurrentAndMovingGc() { |
| if (heap_->IsGcConcurrentAndMoving()) { |
| heap_->DecrementDisableMovingGC(self_); |
| } |
| } |
| private: |
| art::gc::Heap* heap_; |
| art::Thread* self_; |
| }; |
| |
| jvmtiError Redefiner::Run() { |
| art::StackHandleScope<1> hs(self_); |
| // Allocate an array to hold onto all java temporary objects associated with this redefinition. |
| // We will let this be collected after the end of this function. |
| RedefinitionDataHolder holder(&hs, runtime_, self_, &redefinitions_); |
| if (holder.IsNull()) { |
| self_->AssertPendingOOMException(); |
| self_->ClearException(); |
| RecordFailure(ERR(OUT_OF_MEMORY), "Could not allocate storage for temporaries"); |
| return result_; |
| } |
| |
| // First we just allocate the ClassExt and its fields that we need. These can be updated |
| // atomically without any issues (since we allocate the map arrays as empty) so we don't bother |
| // doing a try loop. The other allocations we need to ensure that nothing has changed in the time |
| // between allocating them and pausing all threads before we can update them so we need to do a |
| // try loop. |
| if (!CheckAllRedefinitionAreValid() || |
| !EnsureAllClassAllocationsFinished() || |
| !FinishAllRemainingAllocations(holder) || |
| !CheckAllClassesAreVerified(holder)) { |
| // TODO Null out the ClassExt fields we allocated (if possible, might be racing with another |
| // redefineclass call which made it even bigger. Leak shouldn't be huge (2x array of size |
| // declared_methods_.length) but would be good to get rid of. All other allocations should be |
| // cleaned up by the GC eventually. |
| return result_; |
| } |
| |
| // At this point we can no longer fail without corrupting the runtime state. |
| for (RedefinitionDataIter data = holder.begin(); data != holder.end(); ++data) { |
| if (data.GetSourceClassLoader() == nullptr) { |
| runtime_->GetClassLinker()->AppendToBootClassPath(self_, data.GetRedefinition().GetDexFile()); |
| } |
| } |
| UnregisterAllBreakpoints(); |
| |
| // Disable GC and wait for it to be done if we are a moving GC. This is fine since we are done |
| // allocating so no deadlocks. |
| ScopedDisableConcurrentAndMovingGc sdcamgc(runtime_->GetHeap(), self_); |
| |
| // Do transition to final suspension |
| // TODO We might want to give this its own suspended state! |
| // TODO This isn't right. We need to change state without any chance of suspend ideally! |
| art::ScopedThreadSuspension sts(self_, art::ThreadState::kNative); |
| art::ScopedSuspendAll ssa("Final installation of redefined Classes!", /*long_suspend*/true); |
| for (RedefinitionDataIter data = holder.begin(); data != holder.end(); ++data) { |
| art::ScopedAssertNoThreadSuspension nts("Updating runtime objects for redefinition"); |
| ClassRedefinition& redef = data.GetRedefinition(); |
| if (data.GetSourceClassLoader() != nullptr) { |
| ClassLoaderHelper::UpdateJavaDexFile(data.GetJavaDexFile(), data.GetNewDexFileCookie()); |
| } |
| art::mirror::Class* klass = data.GetMirrorClass(); |
| // TODO Rewrite so we don't do a stack walk for each and every class. |
| redef.FindAndAllocateObsoleteMethods(klass); |
| redef.UpdateClass(klass, data.GetNewDexCache(), data.GetOriginalDexFileBytes()); |
| } |
| // TODO We should check for if any of the redefined methods are intrinsic methods here and, if any |
| // are, force a full-world deoptimization before finishing redefinition. If we don't do this then |
| // methods that have been jitted prior to the current redefinition being applied might continue |
| // to use the old versions of the intrinsics! |
| // TODO Shrink the obsolete method maps if possible? |
| // TODO Do the dex_file release at a more reasonable place. This works but it muddles who really |
| // owns the DexFile and when ownership is transferred. |
| ReleaseAllDexFiles(); |
| return OK; |
| } |
| |
| void Redefiner::ClassRedefinition::UpdateMethods(art::ObjPtr<art::mirror::Class> mclass, |
| art::ObjPtr<art::mirror::DexCache> new_dex_cache, |
| const art::DexFile::ClassDef& class_def) { |
| art::ClassLinker* linker = driver_->runtime_->GetClassLinker(); |
| art::PointerSize image_pointer_size = linker->GetImagePointerSize(); |
| const art::DexFile::TypeId& declaring_class_id = dex_file_->GetTypeId(class_def.class_idx_); |
| const art::DexFile& old_dex_file = mclass->GetDexFile(); |
| // Update methods. |
| for (art::ArtMethod& method : mclass->GetMethods(image_pointer_size)) { |
| const art::DexFile::StringId* new_name_id = dex_file_->FindStringId(method.GetName()); |
| art::dex::TypeIndex method_return_idx = |
| dex_file_->GetIndexForTypeId(*dex_file_->FindTypeId(method.GetReturnTypeDescriptor())); |
| const auto* old_type_list = method.GetParameterTypeList(); |
| std::vector<art::dex::TypeIndex> new_type_list; |
| for (uint32_t i = 0; old_type_list != nullptr && i < old_type_list->Size(); i++) { |
| new_type_list.push_back( |
| dex_file_->GetIndexForTypeId( |
| *dex_file_->FindTypeId( |
| old_dex_file.GetTypeDescriptor( |
| old_dex_file.GetTypeId( |
| old_type_list->GetTypeItem(i).type_idx_))))); |
| } |
| const art::DexFile::ProtoId* proto_id = dex_file_->FindProtoId(method_return_idx, |
| new_type_list); |
| CHECK(proto_id != nullptr || old_type_list == nullptr); |
| const art::DexFile::MethodId* method_id = dex_file_->FindMethodId(declaring_class_id, |
| *new_name_id, |
| *proto_id); |
| CHECK(method_id != nullptr); |
| uint32_t dex_method_idx = dex_file_->GetIndexForMethodId(*method_id); |
| method.SetDexMethodIndex(dex_method_idx); |
| linker->SetEntryPointsToInterpreter(&method); |
| method.SetCodeItemOffset(dex_file_->FindCodeItemOffset(class_def, dex_method_idx)); |
| method.SetDexCacheResolvedMethods(new_dex_cache->GetResolvedMethods(), image_pointer_size); |
| // Clear all the intrinsics related flags. |
| method.ClearAccessFlags(art::kAccIntrinsic | (~art::kAccFlagsNotUsedByIntrinsic)); |
| // Notify the jit that this method is redefined. |
| art::jit::Jit* jit = driver_->runtime_->GetJit(); |
| if (jit != nullptr) { |
| jit->GetCodeCache()->NotifyMethodRedefined(&method); |
| } |
| } |
| } |
| |
| void Redefiner::ClassRedefinition::UpdateFields(art::ObjPtr<art::mirror::Class> mclass) { |
| // TODO The IFields & SFields pointers should be combined like the methods_ arrays were. |
| for (auto fields_iter : {mclass->GetIFields(), mclass->GetSFields()}) { |
| for (art::ArtField& field : fields_iter) { |
| std::string declaring_class_name; |
| const art::DexFile::TypeId* new_declaring_id = |
| dex_file_->FindTypeId(field.GetDeclaringClass()->GetDescriptor(&declaring_class_name)); |
| const art::DexFile::StringId* new_name_id = dex_file_->FindStringId(field.GetName()); |
| const art::DexFile::TypeId* new_type_id = dex_file_->FindTypeId(field.GetTypeDescriptor()); |
| CHECK(new_name_id != nullptr && new_type_id != nullptr && new_declaring_id != nullptr); |
| const art::DexFile::FieldId* new_field_id = |
| dex_file_->FindFieldId(*new_declaring_id, *new_name_id, *new_type_id); |
| CHECK(new_field_id != nullptr); |
| // We only need to update the index since the other data in the ArtField cannot be updated. |
| field.SetDexFieldIndex(dex_file_->GetIndexForFieldId(*new_field_id)); |
| } |
| } |
| } |
| |
| // Performs updates to class that will allow us to verify it. |
| void Redefiner::ClassRedefinition::UpdateClass( |
| art::ObjPtr<art::mirror::Class> mclass, |
| art::ObjPtr<art::mirror::DexCache> new_dex_cache, |
| art::ObjPtr<art::mirror::ByteArray> original_dex_file) { |
| DCHECK_EQ(dex_file_->NumClassDefs(), 1u); |
| const art::DexFile::ClassDef& class_def = dex_file_->GetClassDef(0); |
| UpdateMethods(mclass, new_dex_cache, class_def); |
| UpdateFields(mclass); |
| |
| // Update the class fields. |
| // Need to update class last since the ArtMethod gets its DexFile from the class (which is needed |
| // to call GetReturnTypeDescriptor and GetParameterTypeList above). |
| mclass->SetDexCache(new_dex_cache.Ptr()); |
| mclass->SetDexClassDefIndex(dex_file_->GetIndexForClassDef(class_def)); |
| mclass->SetDexTypeIndex(dex_file_->GetIndexForTypeId(*dex_file_->FindTypeId(class_sig_.c_str()))); |
| art::ObjPtr<art::mirror::ClassExt> ext(mclass->GetExtData()); |
| CHECK(!ext.IsNull()); |
| ext->SetOriginalDexFileBytes(original_dex_file); |
| } |
| |
| // This function does all (java) allocations we need to do for the Class being redefined. |
| // TODO Change this name maybe? |
| bool Redefiner::ClassRedefinition::EnsureClassAllocationsFinished() { |
| art::StackHandleScope<2> hs(driver_->self_); |
| art::Handle<art::mirror::Class> klass(hs.NewHandle( |
| driver_->self_->DecodeJObject(klass_)->AsClass())); |
| if (klass == nullptr) { |
| RecordFailure(ERR(INVALID_CLASS), "Unable to decode class argument!"); |
| return false; |
| } |
| // Allocate the classExt |
| art::Handle<art::mirror::ClassExt> ext(hs.NewHandle(klass->EnsureExtDataPresent(driver_->self_))); |
| if (ext == nullptr) { |
| // No memory. Clear exception (it's not useful) and return error. |
| driver_->self_->AssertPendingOOMException(); |
| driver_->self_->ClearException(); |
| RecordFailure(ERR(OUT_OF_MEMORY), "Could not allocate ClassExt"); |
| return false; |
| } |
| // Allocate the 2 arrays that make up the obsolete methods map. Since the contents of the arrays |
| // are only modified when all threads (other than the modifying one) are suspended we don't need |
| // to worry about missing the unsyncronized writes to the array. We do synchronize when setting it |
| // however, since that can happen at any time. |
| // TODO Clear these after we walk the stacks in order to free them in the (likely?) event there |
| // are no obsolete methods. |
| { |
| art::ObjectLock<art::mirror::ClassExt> lock(driver_->self_, ext); |
| if (!ext->ExtendObsoleteArrays( |
| driver_->self_, klass->GetDeclaredMethodsSlice(art::kRuntimePointerSize).size())) { |
| // OOM. Clear exception and return error. |
| driver_->self_->AssertPendingOOMException(); |
| driver_->self_->ClearException(); |
| RecordFailure(ERR(OUT_OF_MEMORY), "Unable to allocate/extend obsolete methods map"); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| } // namespace openjdkjvmti |