/
oat_file_manager.cc
836 lines (739 loc) · 32.8 KB
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oat_file_manager.cc
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/*
* 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 <memory>
#include <queue>
#include <vector>
#include <sys/stat.h>
#include "android-base/file.h"
#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/mutex-inl.h"
#include "base/sdk_version.h"
#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 "jit/jit.h"
#include "jni/java_vm_ext.h"
#include "jni/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 "thread_pool.h"
#include "vdex_file.h"
#include "verifier/verifier_deps.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<const OatFile> oat_file) {
// Use class_linker vlog to match the log for dex file registration.
VLOG(class_linker) << "Registered oat file " << oat_file->GetLocation();
PaletteNotifyOatFileLoaded(oat_file->GetLocation().c_str());
WriterMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_);
CHECK(!only_use_system_oat_files_ ||
LocationIsTrusted(oat_file->GetLocation(), !Runtime::Current()->DenyArtApexDataFiles()) ||
!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<const OatFile>& 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";
}
}
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<const OatFile> compare(oat_file);
auto it = oat_files_.find(compare);
CHECK(it != oat_files_.end());
oat_files_.erase(it);
compare.release(); // NOLINT b/117926937
}
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<const OatFile>& oat_file : oat_files_) {
const std::vector<const OatDexFile*>& 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<const OatFile>& oat_file : oat_files_) {
if (oat_file->GetLocation() == oat_location) {
return oat_file.get();
}
}
return nullptr;
}
std::vector<const OatFile*> OatFileManager::GetBootOatFiles() const {
std::vector<gc::space::ImageSpace*> image_spaces =
Runtime::Current()->GetHeap()->GetBootImageSpaces();
std::vector<const OatFile*> oat_files;
oat_files.reserve(image_spaces.size());
for (gc::space::ImageSpace* image_space : image_spaces) {
oat_files.push_back(image_space->GetOatFile());
}
return oat_files;
}
OatFileManager::OatFileManager()
: 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<const OatFile*> OatFileManager::RegisterImageOatFiles(
const std::vector<gc::space::ImageSpace*>& spaces) {
std::vector<const OatFile*> oat_files;
oat_files.reserve(spaces.size());
for (gc::space::ImageSpace* space : spaces) {
oat_files.push_back(RegisterOatFile(space->ReleaseOatFile()));
}
return oat_files;
}
bool OatFileManager::ShouldLoadAppImage(const OatFile* source_oat_file) const {
Runtime* const runtime = Runtime::Current();
return kEnableAppImage && (!runtime->IsJavaDebuggable() || source_oat_file->IsDebuggable());
}
std::vector<std::unique_ptr<const DexFile>> OatFileManager::OpenDexFilesFromOat(
const char* dex_location,
jobject class_loader,
jobjectArray dex_elements,
const OatFile** out_oat_file,
std::vector<std::string>* error_msgs) {
ScopedTrace trace(StringPrintf("%s(%s)", __FUNCTION__, dex_location));
CHECK(dex_location != nullptr);
CHECK(error_msgs != nullptr);
// Verify we aren't holding the mutator lock, which could starve GC when
// hitting the disk.
Thread* const self = Thread::Current();
Locks::mutator_lock_->AssertNotHeld(self);
Runtime* const runtime = Runtime::Current();
std::vector<std::unique_ptr<const DexFile>> dex_files;
std::unique_ptr<ClassLoaderContext> context(
ClassLoaderContext::CreateContextForClassLoader(class_loader, dex_elements));
// 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?";
} else if (context != nullptr) {
OatFileAssistant oat_file_assistant(dex_location,
kRuntimeISA,
context.get(),
runtime->GetOatFilesExecutable(),
only_use_system_oat_files_);
// Get the current optimization status for trace debugging.
// Implementation detail note: GetOptimizationStatus will select the same
// oat file as GetBestOatFile used below, and in doing so it already pre-populates
// some OatFileAssistant internal fields.
std::string odex_location;
std::string compilation_filter;
std::string compilation_reason;
std::string odex_status;
oat_file_assistant.GetOptimizationStatus(
&odex_location,
&compilation_filter,
&compilation_reason,
&odex_status);
Runtime::Current()->GetAppInfo()->RegisterOdexStatus(
dex_location,
compilation_filter,
compilation_reason,
odex_status);
ScopedTrace odex_loading(StringPrintf(
"location=%s status=%s filter=%s reason=%s",
odex_location.c_str(),
odex_status.c_str(),
compilation_filter.c_str(),
compilation_reason.c_str()));
// Proceed with oat file loading.
std::unique_ptr<const OatFile> oat_file(oat_file_assistant.GetBestOatFile().release());
VLOG(oat) << "OatFileAssistant(" << dex_location << ").GetBestOatFile()="
<< (oat_file != nullptr ? oat_file->GetLocation() : "")
<< " (executable=" << (oat_file != nullptr ? oat_file->IsExecutable() : false) << ")";
CHECK(oat_file == nullptr || odex_location == oat_file->GetLocation())
<< "OatFileAssistant non-determinism in choosing best oat files. "
<< "optimization-status-location=" << odex_location
<< " best_oat_file-location=" << oat_file->GetLocation();
if (oat_file != nullptr) {
// Load the dex files from the oat file.
bool added_image_space = false;
if (oat_file->IsExecutable()) {
ScopedTrace app_image_timing("AppImage:Loading");
// 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<gc::space::ImageSpace> image_space;
if (ShouldLoadAppImage(oat_file.get())) {
image_space = oat_file_assistant.OpenImageSpace(oat_file.get());
}
if (image_space != nullptr) {
ScopedObjectAccess soa(self);
StackHandleScope<1> hs(self);
Handle<mirror::ClassLoader> h_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader>(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 image_space_timing("Adding image space");
added_image_space = runtime->GetClassLinker()->AddImageSpace(image_space.get(),
h_loader,
/*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(); // NOLINT b/117926937
// 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());
if (oat_file->RequiresImage()) {
LOG(WARNING) << "Loading "
<< oat_file->GetLocation()
<< "non-executable as it requires an image which we failed to load";
// file as non-executable.
OatFileAssistant nonexecutable_oat_file_assistant(dex_location,
kRuntimeISA,
context.get(),
/*load_executable=*/false,
only_use_system_oat_files_);
oat_file.reset(nonexecutable_oat_file_assistant.GetBestOatFile().release());
// The file could be deleted concurrently (for example background
// dexopt, or secondary oat file being deleted by the app).
if (oat_file == nullptr) {
LOG(WARNING) << "Failed to reload oat file non-executable " << dex_location;
}
}
if (oat_file != nullptr) {
dex_files = oat_file_assistant.LoadDexFiles(*oat_file.get(), dex_location);
// Register for tracking.
for (const auto& dex_file : dex_files) {
dex::tracking::RegisterDexFile(dex_file.get());
}
}
}
if (dex_files.empty()) {
ScopedTrace failed_to_open_dex_files("FailedToOpenDexFilesFromOat");
error_msgs->push_back("Failed to open dex files from " + odex_location);
} else {
// Opened dex files from an oat file, madvise them to their loaded state.
for (const std::unique_ptr<const DexFile>& dex_file : dex_files) {
OatDexFile::MadviseDexFile(*dex_file, MadviseState::kMadviseStateAtLoad);
}
}
if (oat_file != nullptr) {
VLOG(class_linker) << "Registering " << oat_file->GetLocation();
*out_oat_file = RegisterOatFile(std::move(oat_file));
}
} else {
// oat_file == nullptr
// Verify if any of the dex files being loaded is already in the class path.
// If so, report an error with the current stack trace.
// Most likely the developer didn't intend to do this because it will waste
// performance and memory.
if (oat_file_assistant.GetBestStatus() == OatFileAssistant::kOatContextOutOfDate) {
std::set<const DexFile*> already_exists_in_classpath =
context->CheckForDuplicateDexFiles(MakeNonOwningPointerVector(dex_files));
if (!already_exists_in_classpath.empty()) {
ScopedTrace duplicate_dex_files("DuplicateDexFilesInContext");
auto duplicate_it = already_exists_in_classpath.begin();
std::string duplicates = (*duplicate_it)->GetLocation();
for (duplicate_it++ ; duplicate_it != already_exists_in_classpath.end(); duplicate_it++) {
duplicates += "," + (*duplicate_it)->GetLocation();
}
std::ostringstream out;
out << "Trying to load dex files which is already loaded in the same ClassLoader "
<< "hierarchy.\n"
<< "This is a strong indication of bad ClassLoader construct which leads to poor "
<< "performance and wastes memory.\n"
<< "The list of duplicate dex files is: " << duplicates << "\n"
<< "The current class loader context is: "
<< context->EncodeContextForOatFile("") << "\n"
<< "Java stack trace:\n";
{
ScopedObjectAccess soa(self);
self->DumpJavaStack(out);
}
// We log this as an ERROR to stress the fact that this is most likely unintended.
// Note that ART cannot do anything about it. It is up to the app to fix their logic.
// Here we are trying to give a heads up on why the app might have performance issues.
LOG(ERROR) << out.str();
}
}
}
}
// If we arrive here with an empty dex files list, it means we fail to load
// it/them through an .oat file.
if (dex_files.empty()) {
std::string error_msg;
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)) {
ScopedTrace fail_to_open_dex_from_apk("FailedToOpenDexFilesFromApk");
LOG(WARNING) << error_msg;
error_msgs->push_back("Failed to open dex files from " + std::string(dex_location)
+ " because: " + error_msg);
}
}
if (Runtime::Current()->GetJit() != nullptr) {
Runtime::Current()->GetJit()->RegisterDexFiles(dex_files, class_loader);
}
// Now that we loaded the dex/odex files, notify the runtime.
// Note that we do this everytime we load dex files.
Runtime::Current()->NotifyDexFileLoaded();
return dex_files;
}
static std::vector<const DexFile::Header*> GetDexFileHeaders(const std::vector<MemMap>& maps) {
std::vector<const DexFile::Header*> headers;
headers.reserve(maps.size());
for (const MemMap& map : maps) {
DCHECK(map.IsValid());
headers.push_back(reinterpret_cast<const DexFile::Header*>(map.Begin()));
}
return headers;
}
std::vector<std::unique_ptr<const DexFile>> OatFileManager::OpenDexFilesFromOat(
std::vector<MemMap>&& dex_mem_maps,
jobject class_loader,
jobjectArray dex_elements,
const OatFile** out_oat_file,
std::vector<std::string>* error_msgs) {
std::vector<std::unique_ptr<const DexFile>> dex_files = OpenDexFilesFromOat_Impl(
std::move(dex_mem_maps),
class_loader,
dex_elements,
out_oat_file,
error_msgs);
if (error_msgs->empty()) {
// Remove write permission from DexFile pages. We do this at the end because
// OatFile assigns OatDexFile pointer in the DexFile objects.
for (std::unique_ptr<const DexFile>& dex_file : dex_files) {
if (!dex_file->DisableWrite()) {
error_msgs->push_back("Failed to make dex file " + dex_file->GetLocation() + " read-only");
}
}
}
if (!error_msgs->empty()) {
return std::vector<std::unique_ptr<const DexFile>>();
}
return dex_files;
}
std::vector<std::unique_ptr<const DexFile>> OatFileManager::OpenDexFilesFromOat_Impl(
std::vector<MemMap>&& dex_mem_maps,
jobject class_loader,
jobjectArray dex_elements,
const OatFile** out_oat_file,
std::vector<std::string>* error_msgs) {
ScopedTrace trace(__FUNCTION__);
std::string error_msg;
DCHECK(error_msgs != nullptr);
// Extract dex file headers from `dex_mem_maps`.
const std::vector<const DexFile::Header*> dex_headers = GetDexFileHeaders(dex_mem_maps);
// Determine dex/vdex locations and the combined location checksum.
std::string dex_location;
std::string vdex_path;
bool has_vdex = OatFileAssistant::AnonymousDexVdexLocation(dex_headers,
kRuntimeISA,
&dex_location,
&vdex_path);
// Attempt to open an existing vdex and check dex file checksums match.
std::unique_ptr<VdexFile> vdex_file = nullptr;
if (has_vdex && OS::FileExists(vdex_path.c_str())) {
vdex_file = VdexFile::Open(vdex_path,
/* writable= */ false,
/* low_4gb= */ false,
/* unquicken= */ false,
&error_msg);
if (vdex_file == nullptr) {
LOG(WARNING) << "Failed to open vdex " << vdex_path << ": " << error_msg;
} else if (!vdex_file->MatchesDexFileChecksums(dex_headers)) {
LOG(WARNING) << "Failed to open vdex " << vdex_path << ": dex file checksum mismatch";
vdex_file.reset(nullptr);
}
}
// Load dex files. Skip structural dex file verification if vdex was found
// and dex checksums matched.
std::vector<std::unique_ptr<const DexFile>> dex_files;
for (size_t i = 0; i < dex_mem_maps.size(); ++i) {
static constexpr bool kVerifyChecksum = true;
const ArtDexFileLoader dex_file_loader;
std::unique_ptr<const DexFile> dex_file(dex_file_loader.Open(
DexFileLoader::GetMultiDexLocation(i, dex_location.c_str()),
dex_headers[i]->checksum_,
std::move(dex_mem_maps[i]),
/* verify= */ (vdex_file == nullptr) && Runtime::Current()->IsVerificationEnabled(),
kVerifyChecksum,
&error_msg));
if (dex_file != nullptr) {
dex::tracking::RegisterDexFile(dex_file.get()); // Register for tracking.
dex_files.push_back(std::move(dex_file));
} else {
error_msgs->push_back("Failed to open dex files from memory: " + error_msg);
}
}
// Check if we should proceed to creating an OatFile instance backed by the vdex.
// We need: (a) an existing vdex, (b) class loader (can be null if invoked via reflection),
// and (c) no errors during dex file loading.
if (vdex_file == nullptr || class_loader == nullptr || !error_msgs->empty()) {
return dex_files;
}
// Attempt to create a class loader context, check OpenDexFiles succeeds (prerequisite
// for using the context later).
std::unique_ptr<ClassLoaderContext> context = ClassLoaderContext::CreateContextForClassLoader(
class_loader,
dex_elements);
if (context == nullptr) {
LOG(ERROR) << "Could not create class loader context for " << vdex_path;
return dex_files;
}
DCHECK(context->OpenDexFiles())
<< "Context created from already opened dex files should not attempt to open again";
// Initialize an OatFile instance backed by the loaded vdex.
std::unique_ptr<OatFile> oat_file(OatFile::OpenFromVdex(MakeNonOwningPointerVector(dex_files),
std::move(vdex_file),
dex_location));
if (oat_file != nullptr) {
VLOG(class_linker) << "Registering " << oat_file->GetLocation();
*out_oat_file = RegisterOatFile(std::move(oat_file));
}
return dex_files;
}
// Check how many vdex files exist in the same directory as the vdex file we are about
// to write. If more than or equal to kAnonymousVdexCacheSize, unlink the least
// recently used one(s) (according to stat-reported atime).
static bool UnlinkLeastRecentlyUsedVdexIfNeeded(const std::string& vdex_path_to_add,
std::string* error_msg) {
std::string basename = android::base::Basename(vdex_path_to_add);
if (!OatFileAssistant::IsAnonymousVdexBasename(basename)) {
// File is not for in memory dex files.
return true;
}
if (OS::FileExists(vdex_path_to_add.c_str())) {
// File already exists and will be overwritten.
// This will not change the number of entries in the cache.
return true;
}
auto last_slash = vdex_path_to_add.rfind('/');
CHECK(last_slash != std::string::npos);
std::string vdex_dir = vdex_path_to_add.substr(0, last_slash + 1);
if (!OS::DirectoryExists(vdex_dir.c_str())) {
// Folder does not exist yet. Cache has zero entries.
return true;
}
std::vector<std::pair<time_t, std::string>> cache;
DIR* c_dir = opendir(vdex_dir.c_str());
if (c_dir == nullptr) {
*error_msg = "Unable to open " + vdex_dir + " to delete unused vdex files";
return false;
}
for (struct dirent* de = readdir(c_dir); de != nullptr; de = readdir(c_dir)) {
if (de->d_type != DT_REG) {
continue;
}
basename = de->d_name;
if (!OatFileAssistant::IsAnonymousVdexBasename(basename)) {
continue;
}
std::string fullname = vdex_dir + basename;
struct stat s;
int rc = TEMP_FAILURE_RETRY(stat(fullname.c_str(), &s));
if (rc == -1) {
*error_msg = "Failed to stat() anonymous vdex file " + fullname;
return false;
}
cache.push_back(std::make_pair(s.st_atime, fullname));
}
CHECK_EQ(0, closedir(c_dir)) << "Unable to close directory.";
if (cache.size() < OatFileManager::kAnonymousVdexCacheSize) {
return true;
}
std::sort(cache.begin(),
cache.end(),
[](const auto& a, const auto& b) { return a.first < b.first; });
for (size_t i = OatFileManager::kAnonymousVdexCacheSize - 1; i < cache.size(); ++i) {
if (unlink(cache[i].second.c_str()) != 0) {
*error_msg = "Could not unlink anonymous vdex file " + cache[i].second;
return false;
}
}
return true;
}
class BackgroundVerificationTask final : public Task {
public:
BackgroundVerificationTask(const std::vector<const DexFile*>& dex_files,
jobject class_loader,
const std::string& vdex_path)
: dex_files_(dex_files),
vdex_path_(vdex_path) {
Thread* const self = Thread::Current();
ScopedObjectAccess soa(self);
// Create a global ref for `class_loader` because it will be accessed from a different thread.
class_loader_ = soa.Vm()->AddGlobalRef(self, soa.Decode<mirror::ClassLoader>(class_loader));
CHECK(class_loader_ != nullptr);
}
~BackgroundVerificationTask() {
Thread* const self = Thread::Current();
ScopedObjectAccess soa(self);
soa.Vm()->DeleteGlobalRef(self, class_loader_);
}
void Run(Thread* self) override {
std::string error_msg;
ClassLinker* const class_linker = Runtime::Current()->GetClassLinker();
verifier::VerifierDeps verifier_deps(dex_files_);
// Iterate over all classes and verify them.
for (const DexFile* dex_file : dex_files_) {
for (uint32_t cdef_idx = 0; cdef_idx < dex_file->NumClassDefs(); cdef_idx++) {
const dex::ClassDef& class_def = dex_file->GetClassDef(cdef_idx);
// Take handles inside the loop. The background verification is low priority
// and we want to minimize the risk of blocking anyone else.
ScopedObjectAccess soa(self);
StackHandleScope<2> hs(self);
Handle<mirror::ClassLoader> h_loader(hs.NewHandle(
soa.Decode<mirror::ClassLoader>(class_loader_)));
Handle<mirror::Class> h_class(hs.NewHandle<mirror::Class>(class_linker->FindClass(
self,
dex_file->GetClassDescriptor(class_def),
h_loader)));
if (h_class == nullptr) {
CHECK(self->IsExceptionPending());
self->ClearException();
continue;
}
if (&h_class->GetDexFile() != dex_file) {
// There is a different class in the class path or a parent class loader
// with the same descriptor. This `h_class` is not resolvable, skip it.
continue;
}
CHECK(h_class->IsResolved()) << h_class->PrettyDescriptor();
class_linker->VerifyClass(self, &verifier_deps, h_class);
if (h_class->IsErroneous()) {
// ClassLinker::VerifyClass throws, which isn't useful here.
CHECK(soa.Self()->IsExceptionPending());
soa.Self()->ClearException();
}
CHECK(h_class->IsVerified() || h_class->IsErroneous())
<< h_class->PrettyDescriptor() << ": state=" << h_class->GetStatus();
if (h_class->IsVerified()) {
verifier_deps.RecordClassVerified(*dex_file, class_def);
}
}
}
// Delete old vdex files if there are too many in the folder.
if (!UnlinkLeastRecentlyUsedVdexIfNeeded(vdex_path_, &error_msg)) {
LOG(ERROR) << "Could not unlink old vdex files " << vdex_path_ << ": " << error_msg;
return;
}
// Construct a vdex file and write `verifier_deps` into it.
if (!VdexFile::WriteToDisk(vdex_path_,
dex_files_,
verifier_deps,
&error_msg)) {
LOG(ERROR) << "Could not write anonymous vdex " << vdex_path_ << ": " << error_msg;
return;
}
}
void Finalize() override {
delete this;
}
private:
const std::vector<const DexFile*> dex_files_;
jobject class_loader_;
const std::string vdex_path_;
DISALLOW_COPY_AND_ASSIGN(BackgroundVerificationTask);
};
void OatFileManager::RunBackgroundVerification(const std::vector<const DexFile*>& dex_files,
jobject class_loader) {
Runtime* const runtime = Runtime::Current();
Thread* const self = Thread::Current();
if (runtime->IsJavaDebuggable()) {
// Threads created by ThreadPool ("runtime threads") are not allowed to load
// classes when debuggable to match class-initialization semantics
// expectations. Do not verify in the background.
return;
}
if (!IsSdkVersionSetAndAtLeast(runtime->GetTargetSdkVersion(), SdkVersion::kQ)) {
// Do not run for legacy apps as they may depend on the previous class loader behaviour.
return;
}
if (runtime->IsShuttingDown(self)) {
// Not allowed to create new threads during runtime shutdown.
return;
}
if (dex_files.size() < 1) {
// Nothing to verify.
return;
}
std::string dex_location = dex_files[0]->GetLocation();
const std::string& data_dir = Runtime::Current()->GetProcessDataDirectory();
if (!android::base::StartsWith(dex_location, data_dir)) {
// For now, we only run background verification for secondary dex files.
// Running it for primary or split APKs could have some undesirable
// side-effects, like overloading the device on app startup.
return;
}
std::string error_msg;
std::string odex_filename;
if (!OatFileAssistant::DexLocationToOdexFilename(dex_location,
kRuntimeISA,
&odex_filename,
&error_msg)) {
LOG(WARNING) << "Could not get odex filename for " << dex_location << ": " << error_msg;
return;
}
if (LocationIsOnArtApexData(odex_filename) && Runtime::Current()->DenyArtApexDataFiles()) {
// Ignore vdex file associated with this odex file as the odex file is not trustworthy.
return;
}
{
WriterMutexLock mu(self, *Locks::oat_file_manager_lock_);
if (verification_thread_pool_ == nullptr) {
verification_thread_pool_.reset(
new ThreadPool("Verification thread pool", /* num_threads= */ 1));
verification_thread_pool_->StartWorkers(self);
}
}
verification_thread_pool_->AddTask(self, new BackgroundVerificationTask(
dex_files,
class_loader,
GetVdexFilename(odex_filename)));
}
void OatFileManager::WaitForWorkersToBeCreated() {
DCHECK(!Runtime::Current()->IsShuttingDown(Thread::Current()))
<< "Cannot create new threads during runtime shutdown";
if (verification_thread_pool_ != nullptr) {
verification_thread_pool_->WaitForWorkersToBeCreated();
}
}
void OatFileManager::DeleteThreadPool() {
verification_thread_pool_.reset(nullptr);
}
void OatFileManager::WaitForBackgroundVerificationTasks() {
if (verification_thread_pool_ != nullptr) {
Thread* const self = Thread::Current();
verification_thread_pool_->WaitForWorkersToBeCreated();
verification_thread_pool_->Wait(self, /* do_work= */ true, /* may_hold_locks= */ false);
}
}
void OatFileManager::SetOnlyUseTrustedOatFiles() {
ReaderMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_);
// Make sure all files that were loaded up to this point are on /system.
// Skip the image files as they can encode locations that don't exist (eg not
// containing the arch in the path, or for JIT zygote /nonx/existent).
std::vector<const OatFile*> boot_vector = GetBootOatFiles();
std::unordered_set<const OatFile*> boot_set(boot_vector.begin(), boot_vector.end());
for (const std::unique_ptr<const OatFile>& oat_file : oat_files_) {
if (boot_set.find(oat_file.get()) == boot_set.end()) {
// This method is called during runtime initialization before we can call
// Runtime::Current()->DenyArtApexDataFiles(). Since we don't want to fail hard if
// the ART APEX data files are untrusted, just treat them as trusted for the check here.
const bool trust_art_apex_data_files = true;
if (!LocationIsTrusted(oat_file->GetLocation(), trust_art_apex_data_files)) {
// When the file is not in a trusted location, we check whether the oat file has any
// AOT or DEX code. It is a fatal error if it has.
if (CompilerFilter::IsAotCompilationEnabled(oat_file->GetCompilerFilter()) ||
oat_file->ContainsDexCode()) {
LOG(FATAL) << "Executing untrusted code from " << oat_file->GetLocation();
}
}
}
}
only_use_system_oat_files_ = true;
}
void OatFileManager::DumpForSigQuit(std::ostream& os) {
ReaderMutexLock mu(Thread::Current(), *Locks::oat_file_manager_lock_);
std::vector<const OatFile*> boot_oat_files = GetBootOatFiles();
for (const std::unique_ptr<const OatFile>& oat_file : oat_files_) {
if (ContainsElement(boot_oat_files, oat_file.get())) {
continue;
}
os << oat_file->GetLocation() << ": " << oat_file->GetCompilerFilter() << "\n";
}
}
} // namespace art