/* * Copyright (C) 2015 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "oat_file_manager.h" #include #include #include #include "android-base/stringprintf.h" #include "android-base/strings.h" #include "art_field-inl.h" #include "base/bit_vector-inl.h" #include "base/file_utils.h" #include "base/logging.h" // For VLOG. #include "base/stl_util.h" #include "base/systrace.h" #include "class_linker.h" #include "class_loader_context.h" #include "dex/art_dex_file_loader.h" #include "dex/dex_file-inl.h" #include "dex/dex_file_loader.h" #include "dex/dex_file_tracking_registrar.h" #include "gc/scoped_gc_critical_section.h" #include "gc/space/image_space.h" #include "handle_scope-inl.h" #include "jni_internal.h" #include "mirror/class_loader.h" #include "mirror/object-inl.h" #include "oat_file.h" #include "oat_file_assistant.h" #include "obj_ptr-inl.h" #include "scoped_thread_state_change-inl.h" #include "thread-current-inl.h" #include "thread_list.h" #include "well_known_classes.h" namespace art { using android::base::StringPrintf; // If true, we attempt to load the application image if it exists. static constexpr bool kEnableAppImage = true; const OatFile* OatFileManager::RegisterOatFile(std::unique_ptr oat_file) { WriterMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_); CHECK(!only_use_system_oat_files_ || LocationIsOnSystem(oat_file->GetLocation().c_str()) || !oat_file->IsExecutable()) << "Registering a non /system oat file: " << oat_file->GetLocation(); DCHECK(oat_file != nullptr); if (kIsDebugBuild) { CHECK(oat_files_.find(oat_file) == oat_files_.end()); for (const std::unique_ptr& existing : oat_files_) { CHECK_NE(oat_file.get(), existing.get()) << oat_file->GetLocation(); // Check that we don't have an oat file with the same address. Copies of the same oat file // should be loaded at different addresses. CHECK_NE(oat_file->Begin(), existing->Begin()) << "Oat file already mapped at that location"; } } have_non_pic_oat_file_ = have_non_pic_oat_file_ || !oat_file->IsPic(); const OatFile* ret = oat_file.get(); oat_files_.insert(std::move(oat_file)); return ret; } void OatFileManager::UnRegisterAndDeleteOatFile(const OatFile* oat_file) { WriterMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_); DCHECK(oat_file != nullptr); std::unique_ptr compare(oat_file); auto it = oat_files_.find(compare); CHECK(it != oat_files_.end()); oat_files_.erase(it); compare.release(); } const OatFile* OatFileManager::FindOpenedOatFileFromDexLocation( const std::string& dex_base_location) const { ReaderMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_); for (const std::unique_ptr& oat_file : oat_files_) { const std::vector& oat_dex_files = oat_file->GetOatDexFiles(); for (const OatDexFile* oat_dex_file : oat_dex_files) { if (DexFileLoader::GetBaseLocation(oat_dex_file->GetDexFileLocation()) == dex_base_location) { return oat_file.get(); } } } return nullptr; } const OatFile* OatFileManager::FindOpenedOatFileFromOatLocation(const std::string& oat_location) const { ReaderMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_); return FindOpenedOatFileFromOatLocationLocked(oat_location); } const OatFile* OatFileManager::FindOpenedOatFileFromOatLocationLocked( const std::string& oat_location) const { for (const std::unique_ptr& oat_file : oat_files_) { if (oat_file->GetLocation() == oat_location) { return oat_file.get(); } } return nullptr; } std::vector OatFileManager::GetBootOatFiles() const { std::vector oat_files; std::vector image_spaces = Runtime::Current()->GetHeap()->GetBootImageSpaces(); for (gc::space::ImageSpace* image_space : image_spaces) { oat_files.push_back(image_space->GetOatFile()); } return oat_files; } const OatFile* OatFileManager::GetPrimaryOatFile() const { ReaderMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_); std::vector boot_oat_files = GetBootOatFiles(); if (!boot_oat_files.empty()) { for (const std::unique_ptr& oat_file : oat_files_) { if (std::find(boot_oat_files.begin(), boot_oat_files.end(), oat_file.get()) == boot_oat_files.end()) { return oat_file.get(); } } } return nullptr; } OatFileManager::OatFileManager() : have_non_pic_oat_file_(false), only_use_system_oat_files_(false) {} OatFileManager::~OatFileManager() { // Explicitly clear oat_files_ since the OatFile destructor calls back into OatFileManager for // UnRegisterOatFileLocation. oat_files_.clear(); } std::vector OatFileManager::RegisterImageOatFiles( std::vector spaces) { std::vector oat_files; for (gc::space::ImageSpace* space : spaces) { oat_files.push_back(RegisterOatFile(space->ReleaseOatFile())); } return oat_files; } class TypeIndexInfo { public: explicit TypeIndexInfo(const DexFile* dex_file) : type_indexes_(GenerateTypeIndexes(dex_file)), iter_(type_indexes_.Indexes().begin()), end_(type_indexes_.Indexes().end()) { } BitVector& GetTypeIndexes() { return type_indexes_; } BitVector::IndexIterator& GetIterator() { return iter_; } BitVector::IndexIterator& GetIteratorEnd() { return end_; } void AdvanceIterator() { iter_++; } private: static BitVector GenerateTypeIndexes(const DexFile* dex_file) { BitVector type_indexes(/*start_bits*/0, /*expandable*/true, Allocator::GetMallocAllocator()); for (uint16_t i = 0; i < dex_file->NumClassDefs(); ++i) { const DexFile::ClassDef& class_def = dex_file->GetClassDef(i); uint16_t type_idx = class_def.class_idx_.index_; type_indexes.SetBit(type_idx); } return type_indexes; } // BitVector with bits set for the type indexes of all classes in the input dex file. BitVector type_indexes_; BitVector::IndexIterator iter_; BitVector::IndexIterator end_; }; class DexFileAndClassPair : ValueObject { public: DexFileAndClassPair(const DexFile* dex_file, TypeIndexInfo* type_info, bool from_loaded_oat) : type_info_(type_info), dex_file_(dex_file), cached_descriptor_(dex_file_->StringByTypeIdx(dex::TypeIndex(*type_info->GetIterator()))), from_loaded_oat_(from_loaded_oat) { type_info_->AdvanceIterator(); } DexFileAndClassPair(const DexFileAndClassPair& rhs) = default; DexFileAndClassPair& operator=(const DexFileAndClassPair& rhs) = default; const char* GetCachedDescriptor() const { return cached_descriptor_; } bool operator<(const DexFileAndClassPair& rhs) const { const int cmp = strcmp(cached_descriptor_, rhs.cached_descriptor_); if (cmp != 0) { // Note that the order must be reversed. We want to iterate over the classes in dex files. // They are sorted lexicographically. Thus, the priority-queue must be a min-queue. return cmp > 0; } return dex_file_ < rhs.dex_file_; } bool DexFileHasMoreClasses() const { return type_info_->GetIterator() != type_info_->GetIteratorEnd(); } void Next() { cached_descriptor_ = dex_file_->StringByTypeIdx(dex::TypeIndex(*type_info_->GetIterator())); type_info_->AdvanceIterator(); } bool FromLoadedOat() const { return from_loaded_oat_; } const DexFile* GetDexFile() const { return dex_file_; } private: TypeIndexInfo* type_info_; const DexFile* dex_file_; const char* cached_descriptor_; bool from_loaded_oat_; // We only need to compare mismatches between what we load now // and what was loaded before. Any old duplicates must have been // OK, and any new "internal" duplicates are as well (they must // be from multidex, which resolves correctly). }; static void AddDexFilesFromOat( const OatFile* oat_file, /*out*/std::vector* dex_files, std::vector>* opened_dex_files) { for (const OatDexFile* oat_dex_file : oat_file->GetOatDexFiles()) { std::string error; std::unique_ptr dex_file = oat_dex_file->OpenDexFile(&error); if (dex_file == nullptr) { LOG(WARNING) << "Could not create dex file from oat file: " << error; } else if (dex_file->NumClassDefs() > 0U) { dex_files->push_back(dex_file.get()); opened_dex_files->push_back(std::move(dex_file)); } } } static void AddNext(/*inout*/DexFileAndClassPair& original, /*inout*/std::priority_queue& heap) { if (original.DexFileHasMoreClasses()) { original.Next(); heap.push(std::move(original)); } } static bool CollisionCheck(std::vector& dex_files_loaded, std::vector& dex_files_unloaded, std::string* error_msg /*out*/) { // Generate type index information for each dex file. std::vector loaded_types; for (const DexFile* dex_file : dex_files_loaded) { loaded_types.push_back(TypeIndexInfo(dex_file)); } std::vector unloaded_types; for (const DexFile* dex_file : dex_files_unloaded) { unloaded_types.push_back(TypeIndexInfo(dex_file)); } // Populate the queue of dex file and class pairs with the loaded and unloaded dex files. std::priority_queue queue; for (size_t i = 0; i < dex_files_loaded.size(); ++i) { if (loaded_types[i].GetIterator() != loaded_types[i].GetIteratorEnd()) { queue.emplace(dex_files_loaded[i], &loaded_types[i], /*from_loaded_oat*/true); } } for (size_t i = 0; i < dex_files_unloaded.size(); ++i) { if (unloaded_types[i].GetIterator() != unloaded_types[i].GetIteratorEnd()) { queue.emplace(dex_files_unloaded[i], &unloaded_types[i], /*from_loaded_oat*/false); } } // Now drain the queue. bool has_duplicates = false; error_msg->clear(); while (!queue.empty()) { // Modifying the top element is only safe if we pop right after. DexFileAndClassPair compare_pop(queue.top()); queue.pop(); // Compare against the following elements. while (!queue.empty()) { DexFileAndClassPair top(queue.top()); if (strcmp(compare_pop.GetCachedDescriptor(), top.GetCachedDescriptor()) == 0) { // Same descriptor. Check whether it's crossing old-oat-files to new-oat-files. if (compare_pop.FromLoadedOat() != top.FromLoadedOat()) { error_msg->append( StringPrintf("Found duplicated class when checking oat files: '%s' in %s and %s\n", compare_pop.GetCachedDescriptor(), compare_pop.GetDexFile()->GetLocation().c_str(), top.GetDexFile()->GetLocation().c_str())); if (!VLOG_IS_ON(oat)) { return true; } has_duplicates = true; } queue.pop(); AddNext(top, queue); } else { // Something else. Done here. break; } } AddNext(compare_pop, queue); } return has_duplicates; } // Check for class-def collisions in dex files. // // This first walks the class loader chain present in the given context, getting all the dex files // from the class loader. // // If the context is null (which means the initial class loader was null or unsupported) // this returns false. b/37777332. // // This first checks whether all class loaders in the context have the same type and // classpath. If so, we exit early. Otherwise, we do the collision check. // // The collision check works by maintaining a heap with one class from each dex file, sorted by the // class descriptor. Then a dex-file/class pair is continually removed from the heap and compared // against the following top element. If the descriptor is the same, it is now checked whether // the two elements agree on whether their dex file was from an already-loaded oat-file or the // new oat file. Any disagreement indicates a collision. bool OatFileManager::HasCollisions(const OatFile* oat_file, const ClassLoaderContext* context, std::string* error_msg /*out*/) const { DCHECK(oat_file != nullptr); DCHECK(error_msg != nullptr); // The context might be null if there are unrecognized class loaders in the chain or they // don't meet sensible sanity conditions. In this case we assume that the app knows what it's // doing and accept the oat file. // Note that this has correctness implications as we cannot guarantee that the class resolution // used during compilation is OK (b/37777332). if (context == nullptr) { LOG(WARNING) << "Skipping duplicate class check due to unsupported classloader"; return false; } // If the pat file loading context matches the context used during compilation then we accept // the oat file without addition checks if (context->VerifyClassLoaderContextMatch(oat_file->GetClassLoaderContext())) { return false; } // The class loader context does not match. Perform a full duplicate classes check. std::vector dex_files_loaded = context->FlattenOpenedDexFiles(); // Vector that holds the newly opened dex files live, this is done to prevent leaks. std::vector> opened_dex_files; ScopedTrace st("Collision check"); // Add dex files from the oat file to check. std::vector dex_files_unloaded; AddDexFilesFromOat(oat_file, &dex_files_unloaded, &opened_dex_files); return CollisionCheck(dex_files_loaded, dex_files_unloaded, error_msg); } std::vector> OatFileManager::OpenDexFilesFromOat( const char* dex_location, jobject class_loader, jobjectArray dex_elements, const OatFile** out_oat_file, std::vector* error_msgs) { ScopedTrace trace(__FUNCTION__); CHECK(dex_location != nullptr); CHECK(error_msgs != nullptr); // Verify we aren't holding the mutator lock, which could starve GC if we // have to generate or relocate an oat file. Thread* const self = Thread::Current(); Locks::mutator_lock_->AssertNotHeld(self); Runtime* const runtime = Runtime::Current(); std::unique_ptr context; // If the class_loader is null there's not much we can do. This happens if a dex files is loaded // directly with DexFile APIs instead of using class loaders. if (class_loader == nullptr) { LOG(WARNING) << "Opening an oat file without a class loader. " << "Are you using the deprecated DexFile APIs?"; context = nullptr; } else { context = ClassLoaderContext::CreateContextForClassLoader(class_loader, dex_elements); } OatFileAssistant oat_file_assistant(dex_location, kRuntimeISA, !runtime->IsAotCompiler(), only_use_system_oat_files_); // Lock the target oat location to avoid races generating and loading the // oat file. std::string error_msg; if (!oat_file_assistant.Lock(/*out*/&error_msg)) { // Don't worry too much if this fails. If it does fail, it's unlikely we // can generate an oat file anyway. VLOG(class_linker) << "OatFileAssistant::Lock: " << error_msg; } const OatFile* source_oat_file = nullptr; if (!oat_file_assistant.IsUpToDate()) { // Update the oat file on disk if we can, based on the --compiler-filter // option derived from the current runtime options. // This may fail, but that's okay. Best effort is all that matters here. // TODO(calin): b/64530081 b/66984396. Pass a null context to verify and compile // secondary dex files in isolation (and avoid to extract/verify the main apk // if it's in the class path). Note this trades correctness for performance // since the resulting slow down is unacceptable in some cases until b/64530081 // is fixed. // We still pass the class loader context when the classpath string of the runtime // is not empty, which is the situation when ART is invoked standalone. ClassLoaderContext* actual_context = Runtime::Current()->GetClassPathString().empty() ? nullptr : context.get(); switch (oat_file_assistant.MakeUpToDate(/*profile_changed*/ false, actual_context, /*out*/ &error_msg)) { case OatFileAssistant::kUpdateFailed: LOG(WARNING) << error_msg; break; case OatFileAssistant::kUpdateNotAttempted: // Avoid spamming the logs if we decided not to attempt making the oat // file up to date. VLOG(oat) << error_msg; break; case OatFileAssistant::kUpdateSucceeded: // Nothing to do. break; } } // Get the oat file on disk. std::unique_ptr oat_file(oat_file_assistant.GetBestOatFile().release()); VLOG(oat) << "OatFileAssistant(" << dex_location << ").GetBestOatFile()=" << reinterpret_cast(oat_file.get()) << " (executable=" << (oat_file != nullptr ? oat_file->IsExecutable() : false) << ")"; if ((class_loader != nullptr || dex_elements != nullptr) && oat_file != nullptr) { // Prevent oat files from being loaded if no class_loader or dex_elements are provided. // This can happen when the deprecated DexFile.(String) is called directly, and it // could load oat files without checking the classpath, which would be incorrect. // Take the file only if it has no collisions, or we must take it because of preopting. bool accept_oat_file = !HasCollisions(oat_file.get(), context.get(), /*out*/ &error_msg); if (!accept_oat_file) { // Failed the collision check. Print warning. if (Runtime::Current()->IsDexFileFallbackEnabled()) { if (!oat_file_assistant.HasOriginalDexFiles()) { // We need to fallback but don't have original dex files. We have to // fallback to opening the existing oat file. This is potentially // unsafe so we warn about it. accept_oat_file = true; LOG(WARNING) << "Dex location " << dex_location << " does not seem to include dex file. " << "Allow oat file use. This is potentially dangerous."; } else { // We have to fallback and found original dex files - extract them from an APK. // Also warn about this operation because it's potentially wasteful. LOG(WARNING) << "Found duplicate classes, falling back to extracting from APK : " << dex_location; LOG(WARNING) << "NOTE: This wastes RAM and hurts startup performance."; } } else { // TODO: We should remove this. The fact that we're here implies -Xno-dex-file-fallback // was set, which means that we should never fallback. If we don't have original dex // files, we should just fail resolution as the flag intended. if (!oat_file_assistant.HasOriginalDexFiles()) { accept_oat_file = true; } LOG(WARNING) << "Found duplicate classes, dex-file-fallback disabled, will be failing to " " load classes for " << dex_location; } LOG(WARNING) << error_msg; } if (accept_oat_file) { VLOG(class_linker) << "Registering " << oat_file->GetLocation(); source_oat_file = RegisterOatFile(std::move(oat_file)); *out_oat_file = source_oat_file; } } std::vector> dex_files; // Load the dex files from the oat file. if (source_oat_file != nullptr) { bool added_image_space = false; if (source_oat_file->IsExecutable()) { // We need to throw away the image space if we are debuggable but the oat-file source of the // image is not otherwise we might get classes with inlined methods or other such things. std::unique_ptr image_space; if (kEnableAppImage && (!runtime->IsJavaDebuggable() || source_oat_file->IsDebuggable())) { image_space = oat_file_assistant.OpenImageSpace(source_oat_file); } else { image_space = nullptr; } if (image_space != nullptr) { ScopedObjectAccess soa(self); StackHandleScope<1> hs(self); Handle h_loader( hs.NewHandle(soa.Decode(class_loader))); // Can not load app image without class loader. if (h_loader != nullptr) { std::string temp_error_msg; // Add image space has a race condition since other threads could be reading from the // spaces array. { ScopedThreadSuspension sts(self, kSuspended); gc::ScopedGCCriticalSection gcs(self, gc::kGcCauseAddRemoveAppImageSpace, gc::kCollectorTypeAddRemoveAppImageSpace); ScopedSuspendAll ssa("Add image space"); runtime->GetHeap()->AddSpace(image_space.get()); } { ScopedTrace trace2(StringPrintf("Adding image space for location %s", dex_location)); added_image_space = runtime->GetClassLinker()->AddImageSpace(image_space.get(), h_loader, dex_elements, dex_location, /*out*/&dex_files, /*out*/&temp_error_msg); } if (added_image_space) { // Successfully added image space to heap, release the map so that it does not get // freed. image_space.release(); // Register for tracking. for (const auto& dex_file : dex_files) { dex::tracking::RegisterDexFile(dex_file.get()); } } else { LOG(INFO) << "Failed to add image file " << temp_error_msg; dex_files.clear(); { ScopedThreadSuspension sts(self, kSuspended); gc::ScopedGCCriticalSection gcs(self, gc::kGcCauseAddRemoveAppImageSpace, gc::kCollectorTypeAddRemoveAppImageSpace); ScopedSuspendAll ssa("Remove image space"); runtime->GetHeap()->RemoveSpace(image_space.get()); } // Non-fatal, don't update error_msg. } } } } if (!added_image_space) { DCHECK(dex_files.empty()); dex_files = oat_file_assistant.LoadDexFiles(*source_oat_file, dex_location); // Register for tracking. for (const auto& dex_file : dex_files) { dex::tracking::RegisterDexFile(dex_file.get()); } } if (dex_files.empty()) { error_msgs->push_back("Failed to open dex files from " + source_oat_file->GetLocation()); } else { // Opened dex files from an oat file, madvise them to their loaded state. for (const std::unique_ptr& dex_file : dex_files) { OatDexFile::MadviseDexFile(*dex_file, MadviseState::kMadviseStateAtLoad); } } } // Fall back to running out of the original dex file if we couldn't load any // dex_files from the oat file. if (dex_files.empty()) { if (oat_file_assistant.HasOriginalDexFiles()) { if (Runtime::Current()->IsDexFileFallbackEnabled()) { static constexpr bool kVerifyChecksum = true; const ArtDexFileLoader dex_file_loader; if (!dex_file_loader.Open(dex_location, dex_location, Runtime::Current()->IsVerificationEnabled(), kVerifyChecksum, /*out*/ &error_msg, &dex_files)) { LOG(WARNING) << error_msg; error_msgs->push_back("Failed to open dex files from " + std::string(dex_location) + " because: " + error_msg); } } else { error_msgs->push_back("Fallback mode disabled, skipping dex files."); } } else { error_msgs->push_back("No original dex files found for dex location " + std::string(dex_location)); } } return dex_files; } void OatFileManager::SetOnlyUseSystemOatFiles() { ReaderMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_); CHECK_EQ(oat_files_.size(), GetBootOatFiles().size()); only_use_system_oat_files_ = true; } void OatFileManager::DumpForSigQuit(std::ostream& os) { ReaderMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_); std::vector boot_oat_files = GetBootOatFiles(); for (const std::unique_ptr& oat_file : oat_files_) { if (ContainsElement(boot_oat_files, oat_file.get())) { continue; } os << oat_file->GetLocation() << ": " << oat_file->GetCompilerFilter() << "\n"; } } } // namespace art