Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 1 | /* Copyright (C) 2016 The Android Open Source Project |
| 2 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 3 | * |
| 4 | * This file implements interfaces from the file jvmti.h. This implementation |
| 5 | * is licensed under the same terms as the file jvmti.h. The |
| 6 | * copyright and license information for the file jvmti.h follows. |
| 7 | * |
| 8 | * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. |
| 9 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 10 | * |
| 11 | * This code is free software; you can redistribute it and/or modify it |
| 12 | * under the terms of the GNU General Public License version 2 only, as |
| 13 | * published by the Free Software Foundation. Oracle designates this |
| 14 | * particular file as subject to the "Classpath" exception as provided |
| 15 | * by Oracle in the LICENSE file that accompanied this code. |
| 16 | * |
| 17 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 18 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 20 | * version 2 for more details (a copy is included in the LICENSE file that |
| 21 | * accompanied this code). |
| 22 | * |
| 23 | * You should have received a copy of the GNU General Public License version |
| 24 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 25 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 26 | * |
| 27 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| 28 | * or visit www.oracle.com if you need additional information or have any |
| 29 | * questions. |
| 30 | */ |
| 31 | |
| 32 | #include "ti_redefine.h" |
| 33 | |
| 34 | #include <limits> |
| 35 | |
Andreas Gampe | 46ee31b | 2016-12-14 10:11:49 -0800 | [diff] [blame] | 36 | #include "android-base/stringprintf.h" |
| 37 | |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 38 | #include "art_jvmti.h" |
| 39 | #include "base/logging.h" |
| 40 | #include "events-inl.h" |
| 41 | #include "gc/allocation_listener.h" |
Alex Light | 6abd539 | 2017-01-05 17:53:00 -0800 | [diff] [blame^] | 42 | #include "gc/heap.h" |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 43 | #include "instrumentation.h" |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 44 | #include "jit/jit.h" |
| 45 | #include "jit/jit_code_cache.h" |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 46 | #include "jni_env_ext-inl.h" |
| 47 | #include "jvmti_allocator.h" |
| 48 | #include "mirror/class.h" |
| 49 | #include "mirror/class_ext.h" |
| 50 | #include "mirror/object.h" |
| 51 | #include "object_lock.h" |
| 52 | #include "runtime.h" |
| 53 | #include "ScopedLocalRef.h" |
| 54 | |
| 55 | namespace openjdkjvmti { |
| 56 | |
Andreas Gampe | 46ee31b | 2016-12-14 10:11:49 -0800 | [diff] [blame] | 57 | using android::base::StringPrintf; |
| 58 | |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 59 | // This visitor walks thread stacks and allocates and sets up the obsolete methods. It also does |
| 60 | // some basic sanity checks that the obsolete method is sane. |
| 61 | class ObsoleteMethodStackVisitor : public art::StackVisitor { |
| 62 | protected: |
| 63 | ObsoleteMethodStackVisitor( |
| 64 | art::Thread* thread, |
| 65 | art::LinearAlloc* allocator, |
| 66 | const std::unordered_set<art::ArtMethod*>& obsoleted_methods, |
| 67 | /*out*/std::unordered_map<art::ArtMethod*, art::ArtMethod*>* obsolete_maps, |
| 68 | /*out*/bool* success, |
| 69 | /*out*/std::string* error_msg) |
| 70 | : StackVisitor(thread, |
| 71 | /*context*/nullptr, |
| 72 | StackVisitor::StackWalkKind::kIncludeInlinedFrames), |
| 73 | allocator_(allocator), |
| 74 | obsoleted_methods_(obsoleted_methods), |
| 75 | obsolete_maps_(obsolete_maps), |
| 76 | success_(success), |
| 77 | is_runtime_frame_(false), |
| 78 | error_msg_(error_msg) { |
| 79 | *success_ = true; |
| 80 | } |
| 81 | |
| 82 | ~ObsoleteMethodStackVisitor() OVERRIDE {} |
| 83 | |
| 84 | public: |
| 85 | // Returns true if we successfully installed obsolete methods on this thread, filling |
| 86 | // obsolete_maps_ with the translations if needed. Returns false and fills error_msg if we fail. |
| 87 | // The stack is cleaned up when we fail. |
| 88 | static bool UpdateObsoleteFrames( |
| 89 | art::Thread* thread, |
| 90 | art::LinearAlloc* allocator, |
| 91 | const std::unordered_set<art::ArtMethod*>& obsoleted_methods, |
| 92 | /*out*/std::unordered_map<art::ArtMethod*, art::ArtMethod*>* obsolete_maps, |
| 93 | /*out*/std::string* error_msg) REQUIRES(art::Locks::mutator_lock_) { |
| 94 | bool success = true; |
| 95 | ObsoleteMethodStackVisitor visitor(thread, |
| 96 | allocator, |
| 97 | obsoleted_methods, |
| 98 | obsolete_maps, |
| 99 | &success, |
| 100 | error_msg); |
| 101 | visitor.WalkStack(); |
| 102 | if (!success) { |
| 103 | RestoreFrames(thread, *obsolete_maps, error_msg); |
| 104 | return false; |
| 105 | } else { |
| 106 | return true; |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | static void RestoreFrames( |
| 111 | art::Thread* thread ATTRIBUTE_UNUSED, |
| 112 | const std::unordered_map<art::ArtMethod*, art::ArtMethod*>& obsolete_maps ATTRIBUTE_UNUSED, |
| 113 | std::string* error_msg) |
| 114 | REQUIRES(art::Locks::mutator_lock_) { |
| 115 | LOG(FATAL) << "Restoring stack frames is not yet supported. Error was: " << *error_msg; |
| 116 | } |
| 117 | |
| 118 | bool VisitFrame() OVERRIDE REQUIRES(art::Locks::mutator_lock_) { |
| 119 | art::ArtMethod* old_method = GetMethod(); |
| 120 | // TODO REMOVE once either current_method doesn't stick around through suspend points or deopt |
| 121 | // works through runtime methods. |
| 122 | bool prev_was_runtime_frame_ = is_runtime_frame_; |
| 123 | is_runtime_frame_ = old_method->IsRuntimeMethod(); |
| 124 | if (obsoleted_methods_.find(old_method) != obsoleted_methods_.end()) { |
| 125 | // The check below works since when we deoptimize we set shadow frames for all frames until a |
| 126 | // native/runtime transition and for those set the return PC to a function that will complete |
| 127 | // the deoptimization. This does leave us with the unfortunate side-effect that frames just |
| 128 | // below runtime frames cannot be deoptimized at the moment. |
| 129 | // TODO REMOVE once either current_method doesn't stick around through suspend points or deopt |
| 130 | // works through runtime methods. |
| 131 | // TODO b/33616143 |
| 132 | if (!IsShadowFrame() && prev_was_runtime_frame_) { |
| 133 | *error_msg_ = StringPrintf("Deoptimization failed due to runtime method in stack."); |
| 134 | *success_ = false; |
| 135 | return false; |
| 136 | } |
| 137 | // We cannot ensure that the right dex file is used in inlined frames so we don't support |
| 138 | // redefining them. |
| 139 | DCHECK(!IsInInlinedFrame()) << "Inlined frames are not supported when using redefinition"; |
| 140 | // TODO We should really support intrinsic obsolete methods. |
| 141 | // TODO We should really support redefining intrinsics. |
| 142 | // We don't support intrinsics so check for them here. |
| 143 | DCHECK(!old_method->IsIntrinsic()); |
| 144 | art::ArtMethod* new_obsolete_method = nullptr; |
| 145 | auto obsolete_method_pair = obsolete_maps_->find(old_method); |
| 146 | if (obsolete_method_pair == obsolete_maps_->end()) { |
| 147 | // Create a new Obsolete Method and put it in the list. |
| 148 | art::Runtime* runtime = art::Runtime::Current(); |
| 149 | art::ClassLinker* cl = runtime->GetClassLinker(); |
| 150 | auto ptr_size = cl->GetImagePointerSize(); |
| 151 | const size_t method_size = art::ArtMethod::Size(ptr_size); |
| 152 | auto* method_storage = allocator_->Alloc(GetThread(), method_size); |
| 153 | if (method_storage == nullptr) { |
| 154 | *success_ = false; |
| 155 | *error_msg_ = StringPrintf("Unable to allocate storage for obsolete version of '%s'", |
| 156 | old_method->PrettyMethod().c_str()); |
| 157 | return false; |
| 158 | } |
| 159 | new_obsolete_method = new (method_storage) art::ArtMethod(); |
| 160 | new_obsolete_method->CopyFrom(old_method, ptr_size); |
| 161 | DCHECK_EQ(new_obsolete_method->GetDeclaringClass(), old_method->GetDeclaringClass()); |
| 162 | new_obsolete_method->SetIsObsolete(); |
| 163 | obsolete_maps_->insert({old_method, new_obsolete_method}); |
| 164 | // Update JIT Data structures to point to the new method. |
| 165 | art::jit::Jit* jit = art::Runtime::Current()->GetJit(); |
| 166 | if (jit != nullptr) { |
| 167 | // Notify the JIT we are making this obsolete method. It will update the jit's internal |
| 168 | // structures to keep track of the new obsolete method. |
| 169 | jit->GetCodeCache()->MoveObsoleteMethod(old_method, new_obsolete_method); |
| 170 | } |
| 171 | } else { |
| 172 | new_obsolete_method = obsolete_method_pair->second; |
| 173 | } |
| 174 | DCHECK(new_obsolete_method != nullptr); |
| 175 | SetMethod(new_obsolete_method); |
| 176 | } |
| 177 | return true; |
| 178 | } |
| 179 | |
| 180 | private: |
| 181 | // The linear allocator we should use to make new methods. |
| 182 | art::LinearAlloc* allocator_; |
| 183 | // The set of all methods which could be obsoleted. |
| 184 | const std::unordered_set<art::ArtMethod*>& obsoleted_methods_; |
| 185 | // A map from the original to the newly allocated obsolete method for frames on this thread. The |
| 186 | // values in this map must be added to the obsolete_methods_ (and obsolete_dex_caches_) fields of |
| 187 | // the redefined classes ClassExt by the caller. |
| 188 | std::unordered_map<art::ArtMethod*, art::ArtMethod*>* obsolete_maps_; |
| 189 | bool* success_; |
| 190 | // TODO REMOVE once either current_method doesn't stick around through suspend points or deopt |
| 191 | // works through runtime methods. |
| 192 | bool is_runtime_frame_; |
| 193 | std::string* error_msg_; |
| 194 | }; |
| 195 | |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 196 | // Moves dex data to an anonymous, read-only mmap'd region. |
| 197 | std::unique_ptr<art::MemMap> Redefiner::MoveDataToMemMap(const std::string& original_location, |
| 198 | jint data_len, |
| 199 | unsigned char* dex_data, |
| 200 | std::string* error_msg) { |
| 201 | std::unique_ptr<art::MemMap> map(art::MemMap::MapAnonymous( |
Andreas Gampe | 46ee31b | 2016-12-14 10:11:49 -0800 | [diff] [blame] | 202 | StringPrintf("%s-transformed", original_location.c_str()).c_str(), |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 203 | nullptr, |
| 204 | data_len, |
| 205 | PROT_READ|PROT_WRITE, |
| 206 | /*low_4gb*/false, |
| 207 | /*reuse*/false, |
| 208 | error_msg)); |
| 209 | if (map == nullptr) { |
| 210 | return map; |
| 211 | } |
| 212 | memcpy(map->Begin(), dex_data, data_len); |
Alex Light | 0b77257 | 2016-12-02 17:27:31 -0800 | [diff] [blame] | 213 | // Make the dex files mmap read only. This matches how other DexFiles are mmaped and prevents |
| 214 | // programs from corrupting it. |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 215 | map->Protect(PROT_READ); |
| 216 | return map; |
| 217 | } |
| 218 | |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 219 | // TODO This should handle doing multiple classes at once so we need to do less cleanup when things |
| 220 | // go wrong. |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 221 | jvmtiError Redefiner::RedefineClass(ArtJvmTiEnv* env, |
| 222 | art::Runtime* runtime, |
| 223 | art::Thread* self, |
| 224 | jclass klass, |
| 225 | const std::string& original_dex_location, |
| 226 | jint data_len, |
| 227 | unsigned char* dex_data, |
| 228 | std::string* error_msg) { |
| 229 | std::unique_ptr<art::MemMap> map(MoveDataToMemMap(original_dex_location, |
| 230 | data_len, |
| 231 | dex_data, |
| 232 | error_msg)); |
| 233 | std::ostringstream os; |
| 234 | char* generic_ptr_unused = nullptr; |
| 235 | char* signature_ptr = nullptr; |
| 236 | if (env->GetClassSignature(klass, &signature_ptr, &generic_ptr_unused) != OK) { |
| 237 | signature_ptr = const_cast<char*>("<UNKNOWN CLASS>"); |
| 238 | } |
| 239 | if (map.get() == nullptr) { |
| 240 | os << "Failed to create anonymous mmap for modified dex file of class " << signature_ptr |
| 241 | << "in dex file " << original_dex_location << " because: " << *error_msg; |
| 242 | *error_msg = os.str(); |
| 243 | return ERR(OUT_OF_MEMORY); |
| 244 | } |
| 245 | if (map->Size() < sizeof(art::DexFile::Header)) { |
| 246 | *error_msg = "Could not read dex file header because dex_data was too short"; |
| 247 | return ERR(INVALID_CLASS_FORMAT); |
| 248 | } |
| 249 | uint32_t checksum = reinterpret_cast<const art::DexFile::Header*>(map->Begin())->checksum_; |
| 250 | std::unique_ptr<const art::DexFile> dex_file(art::DexFile::Open(map->GetName(), |
| 251 | checksum, |
| 252 | std::move(map), |
| 253 | /*verify*/true, |
| 254 | /*verify_checksum*/true, |
| 255 | error_msg)); |
| 256 | if (dex_file.get() == nullptr) { |
| 257 | os << "Unable to load modified dex file for " << signature_ptr << ": " << *error_msg; |
| 258 | *error_msg = os.str(); |
| 259 | return ERR(INVALID_CLASS_FORMAT); |
| 260 | } |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 261 | // Stop JIT for the duration of this redefine since the JIT might concurrently compile a method we |
| 262 | // are going to redefine. |
| 263 | art::jit::ScopedJitSuspend suspend_jit; |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 264 | // Get shared mutator lock. |
| 265 | art::ScopedObjectAccess soa(self); |
| 266 | art::StackHandleScope<1> hs(self); |
| 267 | Redefiner r(runtime, self, klass, signature_ptr, dex_file, error_msg); |
| 268 | // Lock around this class to avoid races. |
| 269 | art::ObjectLock<art::mirror::Class> lock(self, hs.NewHandle(r.GetMirrorClass())); |
| 270 | return r.Run(); |
| 271 | } |
| 272 | |
| 273 | // TODO *MAJOR* This should return the actual source java.lang.DexFile object for the klass. |
| 274 | // TODO Make mirror of DexFile and associated types to make this less hellish. |
| 275 | // TODO Make mirror of BaseDexClassLoader and associated types to make this less hellish. |
| 276 | art::mirror::Object* Redefiner::FindSourceDexFileObject( |
| 277 | art::Handle<art::mirror::ClassLoader> loader) { |
| 278 | const char* dex_path_list_element_array_name = "[Ldalvik/system/DexPathList$Element;"; |
| 279 | const char* dex_path_list_element_name = "Ldalvik/system/DexPathList$Element;"; |
| 280 | const char* dex_file_name = "Ldalvik/system/DexFile;"; |
| 281 | const char* dex_path_list_name = "Ldalvik/system/DexPathList;"; |
| 282 | const char* dex_class_loader_name = "Ldalvik/system/BaseDexClassLoader;"; |
| 283 | |
| 284 | CHECK(!self_->IsExceptionPending()); |
| 285 | art::StackHandleScope<11> hs(self_); |
| 286 | art::ClassLinker* class_linker = runtime_->GetClassLinker(); |
| 287 | |
| 288 | art::Handle<art::mirror::ClassLoader> null_loader(hs.NewHandle<art::mirror::ClassLoader>( |
| 289 | nullptr)); |
| 290 | art::Handle<art::mirror::Class> base_dex_loader_class(hs.NewHandle(class_linker->FindClass( |
| 291 | self_, dex_class_loader_name, null_loader))); |
| 292 | |
| 293 | // Get all the ArtFields so we can look in the BaseDexClassLoader |
| 294 | art::ArtField* path_list_field = base_dex_loader_class->FindDeclaredInstanceField( |
| 295 | "pathList", dex_path_list_name); |
| 296 | CHECK(path_list_field != nullptr); |
| 297 | |
| 298 | art::ArtField* dex_path_list_element_field = |
| 299 | class_linker->FindClass(self_, dex_path_list_name, null_loader) |
| 300 | ->FindDeclaredInstanceField("dexElements", dex_path_list_element_array_name); |
| 301 | CHECK(dex_path_list_element_field != nullptr); |
| 302 | |
| 303 | art::ArtField* element_dex_file_field = |
| 304 | class_linker->FindClass(self_, dex_path_list_element_name, null_loader) |
| 305 | ->FindDeclaredInstanceField("dexFile", dex_file_name); |
| 306 | CHECK(element_dex_file_field != nullptr); |
| 307 | |
| 308 | // Check if loader is a BaseDexClassLoader |
| 309 | art::Handle<art::mirror::Class> loader_class(hs.NewHandle(loader->GetClass())); |
| 310 | if (!loader_class->IsSubClass(base_dex_loader_class.Get())) { |
| 311 | LOG(ERROR) << "The classloader is not a BaseDexClassLoader which is currently the only " |
| 312 | << "supported class loader type!"; |
| 313 | return nullptr; |
| 314 | } |
| 315 | // Start navigating the fields of the loader (now known to be a BaseDexClassLoader derivative) |
| 316 | art::Handle<art::mirror::Object> path_list( |
| 317 | hs.NewHandle(path_list_field->GetObject(loader.Get()))); |
| 318 | CHECK(path_list.Get() != nullptr); |
| 319 | CHECK(!self_->IsExceptionPending()); |
| 320 | art::Handle<art::mirror::ObjectArray<art::mirror::Object>> dex_elements_list(hs.NewHandle( |
| 321 | dex_path_list_element_field->GetObject(path_list.Get())-> |
| 322 | AsObjectArray<art::mirror::Object>())); |
| 323 | CHECK(!self_->IsExceptionPending()); |
| 324 | CHECK(dex_elements_list.Get() != nullptr); |
| 325 | size_t num_elements = dex_elements_list->GetLength(); |
| 326 | art::MutableHandle<art::mirror::Object> current_element( |
| 327 | hs.NewHandle<art::mirror::Object>(nullptr)); |
| 328 | art::MutableHandle<art::mirror::Object> first_dex_file( |
| 329 | hs.NewHandle<art::mirror::Object>(nullptr)); |
| 330 | // Iterate over the DexPathList$Element to find the right one |
| 331 | // TODO Or not ATM just return the first one. |
| 332 | for (size_t i = 0; i < num_elements; i++) { |
| 333 | current_element.Assign(dex_elements_list->Get(i)); |
| 334 | CHECK(current_element.Get() != nullptr); |
| 335 | CHECK(!self_->IsExceptionPending()); |
| 336 | CHECK(dex_elements_list.Get() != nullptr); |
| 337 | CHECK_EQ(current_element->GetClass(), class_linker->FindClass(self_, |
| 338 | dex_path_list_element_name, |
| 339 | null_loader)); |
| 340 | // TODO It would be cleaner to put the art::DexFile into the dalvik.system.DexFile the class |
| 341 | // comes from but it is more annoying because we would need to find this class. It is not |
| 342 | // necessary for proper function since we just need to be in front of the classes old dex file |
| 343 | // in the path. |
| 344 | first_dex_file.Assign(element_dex_file_field->GetObject(current_element.Get())); |
| 345 | if (first_dex_file.Get() != nullptr) { |
| 346 | return first_dex_file.Get(); |
| 347 | } |
| 348 | } |
| 349 | return nullptr; |
| 350 | } |
| 351 | |
| 352 | art::mirror::Class* Redefiner::GetMirrorClass() { |
| 353 | return self_->DecodeJObject(klass_)->AsClass(); |
| 354 | } |
| 355 | |
| 356 | art::mirror::ClassLoader* Redefiner::GetClassLoader() { |
| 357 | return GetMirrorClass()->GetClassLoader(); |
| 358 | } |
| 359 | |
| 360 | art::mirror::DexCache* Redefiner::CreateNewDexCache(art::Handle<art::mirror::ClassLoader> loader) { |
| 361 | return runtime_->GetClassLinker()->RegisterDexFile(*dex_file_, loader.Get()); |
| 362 | } |
| 363 | |
| 364 | // TODO Really wishing I had that mirror of java.lang.DexFile now. |
| 365 | art::mirror::LongArray* Redefiner::AllocateDexFileCookie( |
| 366 | art::Handle<art::mirror::Object> java_dex_file_obj) { |
| 367 | art::StackHandleScope<2> hs(self_); |
| 368 | // mCookie is nulled out if the DexFile has been closed but mInternalCookie sticks around until |
| 369 | // the object is finalized. Since they always point to the same array if mCookie is not null we |
| 370 | // just use the mInternalCookie field. We will update one or both of these fields later. |
| 371 | // TODO Should I get the class from the classloader or directly? |
| 372 | art::ArtField* internal_cookie_field = java_dex_file_obj->GetClass()->FindDeclaredInstanceField( |
| 373 | "mInternalCookie", "Ljava/lang/Object;"); |
| 374 | // TODO Add check that mCookie is either null or same as mInternalCookie |
| 375 | CHECK(internal_cookie_field != nullptr); |
| 376 | art::Handle<art::mirror::LongArray> cookie( |
| 377 | hs.NewHandle(internal_cookie_field->GetObject(java_dex_file_obj.Get())->AsLongArray())); |
| 378 | // TODO Maybe make these non-fatal. |
| 379 | CHECK(cookie.Get() != nullptr); |
| 380 | CHECK_GE(cookie->GetLength(), 1); |
| 381 | art::Handle<art::mirror::LongArray> new_cookie( |
| 382 | hs.NewHandle(art::mirror::LongArray::Alloc(self_, cookie->GetLength() + 1))); |
| 383 | if (new_cookie.Get() == nullptr) { |
| 384 | self_->AssertPendingOOMException(); |
| 385 | return nullptr; |
| 386 | } |
| 387 | // Copy the oat-dex field at the start. |
| 388 | // TODO Should I clear this field? |
| 389 | // TODO This is a really crappy thing here with the first element being different. |
| 390 | new_cookie->SetWithoutChecks<false>(0, cookie->GetWithoutChecks(0)); |
| 391 | new_cookie->SetWithoutChecks<false>( |
| 392 | 1, static_cast<int64_t>(reinterpret_cast<intptr_t>(dex_file_.get()))); |
| 393 | new_cookie->Memcpy(2, cookie.Get(), 1, cookie->GetLength() - 1); |
| 394 | return new_cookie.Get(); |
| 395 | } |
| 396 | |
| 397 | void Redefiner::RecordFailure(jvmtiError result, const std::string& error_msg) { |
Andreas Gampe | 46ee31b | 2016-12-14 10:11:49 -0800 | [diff] [blame] | 398 | *error_msg_ = StringPrintf("Unable to perform redefinition of '%s': %s", |
| 399 | class_sig_, |
| 400 | error_msg.c_str()); |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 401 | result_ = result; |
| 402 | } |
| 403 | |
| 404 | bool Redefiner::FinishRemainingAllocations( |
| 405 | /*out*/art::MutableHandle<art::mirror::ClassLoader>* source_class_loader, |
| 406 | /*out*/art::MutableHandle<art::mirror::Object>* java_dex_file_obj, |
| 407 | /*out*/art::MutableHandle<art::mirror::LongArray>* new_dex_file_cookie, |
| 408 | /*out*/art::MutableHandle<art::mirror::DexCache>* new_dex_cache) { |
| 409 | art::StackHandleScope<4> hs(self_); |
| 410 | // This shouldn't allocate |
| 411 | art::Handle<art::mirror::ClassLoader> loader(hs.NewHandle(GetClassLoader())); |
| 412 | if (loader.Get() == nullptr) { |
| 413 | // TODO Better error msg. |
| 414 | RecordFailure(ERR(INTERNAL), "Unable to find class loader!"); |
| 415 | return false; |
| 416 | } |
| 417 | art::Handle<art::mirror::Object> dex_file_obj(hs.NewHandle(FindSourceDexFileObject(loader))); |
| 418 | if (dex_file_obj.Get() == nullptr) { |
| 419 | // TODO Better error msg. |
| 420 | RecordFailure(ERR(INTERNAL), "Unable to find class loader!"); |
| 421 | return false; |
| 422 | } |
| 423 | art::Handle<art::mirror::LongArray> new_cookie(hs.NewHandle(AllocateDexFileCookie(dex_file_obj))); |
| 424 | if (new_cookie.Get() == nullptr) { |
| 425 | self_->AssertPendingOOMException(); |
| 426 | self_->ClearException(); |
| 427 | RecordFailure(ERR(OUT_OF_MEMORY), "Unable to allocate dex file array for class loader"); |
| 428 | return false; |
| 429 | } |
| 430 | art::Handle<art::mirror::DexCache> dex_cache(hs.NewHandle(CreateNewDexCache(loader))); |
| 431 | if (dex_cache.Get() == nullptr) { |
| 432 | self_->AssertPendingOOMException(); |
| 433 | self_->ClearException(); |
| 434 | RecordFailure(ERR(OUT_OF_MEMORY), "Unable to allocate DexCache"); |
| 435 | return false; |
| 436 | } |
| 437 | source_class_loader->Assign(loader.Get()); |
| 438 | java_dex_file_obj->Assign(dex_file_obj.Get()); |
| 439 | new_dex_file_cookie->Assign(new_cookie.Get()); |
| 440 | new_dex_cache->Assign(dex_cache.Get()); |
| 441 | return true; |
| 442 | } |
| 443 | |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 444 | struct CallbackCtx { |
| 445 | Redefiner* const r; |
| 446 | art::LinearAlloc* allocator; |
| 447 | std::unordered_map<art::ArtMethod*, art::ArtMethod*> obsolete_map; |
| 448 | std::unordered_set<art::ArtMethod*> obsolete_methods; |
| 449 | bool success; |
| 450 | std::string* error_msg; |
| 451 | |
| 452 | CallbackCtx(Redefiner* self, art::LinearAlloc* alloc, std::string* error) |
| 453 | : r(self), allocator(alloc), success(true), error_msg(error) {} |
| 454 | }; |
| 455 | |
| 456 | void DoRestoreObsoleteMethodsCallback(art::Thread* t, void* vdata) NO_THREAD_SAFETY_ANALYSIS { |
| 457 | CallbackCtx* data = reinterpret_cast<CallbackCtx*>(vdata); |
| 458 | ObsoleteMethodStackVisitor::RestoreFrames(t, data->obsolete_map, data->error_msg); |
| 459 | } |
| 460 | |
| 461 | void DoAllocateObsoleteMethodsCallback(art::Thread* t, void* vdata) NO_THREAD_SAFETY_ANALYSIS { |
| 462 | CallbackCtx* data = reinterpret_cast<CallbackCtx*>(vdata); |
| 463 | if (data->success) { |
| 464 | // Don't do anything if we already failed once. |
| 465 | data->success = ObsoleteMethodStackVisitor::UpdateObsoleteFrames(t, |
| 466 | data->allocator, |
| 467 | data->obsolete_methods, |
| 468 | &data->obsolete_map, |
| 469 | data->error_msg); |
| 470 | } |
| 471 | } |
| 472 | |
| 473 | // This creates any ArtMethod* structures needed for obsolete methods and ensures that the stack is |
| 474 | // updated so they will be run. |
| 475 | bool Redefiner::FindAndAllocateObsoleteMethods(art::mirror::Class* art_klass) { |
| 476 | art::ScopedAssertNoThreadSuspension ns("No thread suspension during thread stack walking"); |
| 477 | art::mirror::ClassExt* ext = art_klass->GetExtData(); |
| 478 | CHECK(ext->GetObsoleteMethods() != nullptr); |
| 479 | CallbackCtx ctx(this, art_klass->GetClassLoader()->GetAllocator(), error_msg_); |
| 480 | // Add all the declared methods to the map |
| 481 | for (auto& m : art_klass->GetDeclaredMethods(art::kRuntimePointerSize)) { |
| 482 | ctx.obsolete_methods.insert(&m); |
| 483 | } |
| 484 | for (art::ArtMethod* old_method : ctx.obsolete_methods) { |
| 485 | if (old_method->IsIntrinsic()) { |
| 486 | *error_msg_ = StringPrintf("Method '%s' is intrinsic and cannot be made obsolete!", |
| 487 | old_method->PrettyMethod().c_str()); |
| 488 | return false; |
| 489 | } |
| 490 | } |
| 491 | { |
| 492 | art::MutexLock mu(self_, *art::Locks::thread_list_lock_); |
| 493 | art::ThreadList* list = art::Runtime::Current()->GetThreadList(); |
| 494 | list->ForEach(DoAllocateObsoleteMethodsCallback, static_cast<void*>(&ctx)); |
| 495 | if (!ctx.success) { |
| 496 | list->ForEach(DoRestoreObsoleteMethodsCallback, static_cast<void*>(&ctx)); |
| 497 | return false; |
| 498 | } |
| 499 | } |
| 500 | FillObsoleteMethodMap(art_klass, ctx.obsolete_map); |
| 501 | return true; |
| 502 | } |
| 503 | |
| 504 | // Fills the obsolete method map in the art_klass's extData. This is so obsolete methods are able to |
| 505 | // figure out their DexCaches. |
| 506 | void Redefiner::FillObsoleteMethodMap( |
| 507 | art::mirror::Class* art_klass, |
| 508 | const std::unordered_map<art::ArtMethod*, art::ArtMethod*>& obsoletes) { |
| 509 | int32_t index = 0; |
| 510 | art::mirror::ClassExt* ext_data = art_klass->GetExtData(); |
| 511 | art::mirror::PointerArray* obsolete_methods = ext_data->GetObsoleteMethods(); |
| 512 | art::mirror::ObjectArray<art::mirror::DexCache>* obsolete_dex_caches = |
| 513 | ext_data->GetObsoleteDexCaches(); |
| 514 | int32_t num_method_slots = obsolete_methods->GetLength(); |
| 515 | // Find the first empty index. |
| 516 | for (; index < num_method_slots; index++) { |
| 517 | if (obsolete_methods->GetElementPtrSize<art::ArtMethod*>( |
| 518 | index, art::kRuntimePointerSize) == nullptr) { |
| 519 | break; |
| 520 | } |
| 521 | } |
| 522 | // Make sure we have enough space. |
| 523 | CHECK_GT(num_method_slots, static_cast<int32_t>(obsoletes.size() + index)); |
| 524 | CHECK(obsolete_dex_caches->Get(index) == nullptr); |
| 525 | // Fill in the map. |
| 526 | for (auto& obs : obsoletes) { |
| 527 | obsolete_methods->SetElementPtrSize(index, obs.second, art::kRuntimePointerSize); |
| 528 | obsolete_dex_caches->Set(index, art_klass->GetDexCache()); |
| 529 | index++; |
| 530 | } |
| 531 | } |
| 532 | |
| 533 | // TODO It should be possible to only deoptimize the specific obsolete methods. |
| 534 | // TODO ReJitEverything can (sort of) fail. In certain cases it will skip deoptimizing some frames. |
| 535 | // If one of these frames is an obsolete method we have a problem. b/33616143 |
| 536 | // TODO This shouldn't be necessary once we can ensure that the current method is not kept in |
| 537 | // registers across suspend points. |
| 538 | // TODO Pending b/33630159 |
| 539 | void Redefiner::EnsureObsoleteMethodsAreDeoptimized() { |
| 540 | art::ScopedAssertNoThreadSuspension nts("Deoptimizing everything!"); |
| 541 | art::instrumentation::Instrumentation* i = runtime_->GetInstrumentation(); |
| 542 | i->ReJitEverything("libOpenJkdJvmti - Class Redefinition"); |
| 543 | } |
| 544 | |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 545 | jvmtiError Redefiner::Run() { |
| 546 | art::StackHandleScope<5> hs(self_); |
| 547 | // TODO We might want to have a global lock (or one based on the class being redefined at least) |
| 548 | // in order to make cleanup easier. Not a huge deal though. |
| 549 | // |
| 550 | // First we just allocate the ClassExt and its fields that we need. These can be updated |
| 551 | // atomically without any issues (since we allocate the map arrays as empty) so we don't bother |
| 552 | // doing a try loop. The other allocations we need to ensure that nothing has changed in the time |
| 553 | // between allocating them and pausing all threads before we can update them so we need to do a |
| 554 | // try loop. |
| 555 | if (!EnsureRedefinitionIsValid() || !EnsureClassAllocationsFinished()) { |
| 556 | return result_; |
| 557 | } |
| 558 | art::MutableHandle<art::mirror::ClassLoader> source_class_loader( |
| 559 | hs.NewHandle<art::mirror::ClassLoader>(nullptr)); |
| 560 | art::MutableHandle<art::mirror::Object> java_dex_file( |
| 561 | hs.NewHandle<art::mirror::Object>(nullptr)); |
| 562 | art::MutableHandle<art::mirror::LongArray> new_dex_file_cookie( |
| 563 | hs.NewHandle<art::mirror::LongArray>(nullptr)); |
| 564 | art::MutableHandle<art::mirror::DexCache> new_dex_cache( |
| 565 | hs.NewHandle<art::mirror::DexCache>(nullptr)); |
| 566 | if (!FinishRemainingAllocations(&source_class_loader, |
| 567 | &java_dex_file, |
| 568 | &new_dex_file_cookie, |
| 569 | &new_dex_cache)) { |
| 570 | // TODO Null out the ClassExt fields we allocated (if possible, might be racing with another |
| 571 | // redefineclass call which made it even bigger. Leak shouldn't be huge (2x array of size |
| 572 | // declared_methods_.length) but would be good to get rid of. |
| 573 | // new_dex_file_cookie & new_dex_cache should be cleaned up by the GC. |
| 574 | return result_; |
| 575 | } |
| 576 | // Get the mirror class now that we aren't allocating anymore. |
| 577 | art::Handle<art::mirror::Class> art_class(hs.NewHandle(GetMirrorClass())); |
Alex Light | 6abd539 | 2017-01-05 17:53:00 -0800 | [diff] [blame^] | 578 | // Disable GC and wait for it to be done if we are a moving GC. This is fine since we are done |
| 579 | // allocating so no deadlocks. |
| 580 | art::gc::Heap* heap = runtime_->GetHeap(); |
| 581 | if (heap->IsGcConcurrentAndMoving()) { |
| 582 | // GC moving objects can cause deadlocks as we are deoptimizing the stack. |
| 583 | heap->IncrementDisableMovingGC(self_); |
| 584 | } |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 585 | // Enable assertion that this thread isn't interrupted during this installation. |
| 586 | // After this we will need to do real cleanup in case of failure. Prior to this we could simply |
| 587 | // return and would let everything get cleaned up or harmlessly leaked. |
| 588 | // Do transition to final suspension |
| 589 | // TODO We might want to give this its own suspended state! |
| 590 | // TODO This isn't right. We need to change state without any chance of suspend ideally! |
| 591 | self_->TransitionFromRunnableToSuspended(art::ThreadState::kNative); |
| 592 | runtime_->GetThreadList()->SuspendAll( |
| 593 | "Final installation of redefined Class!", /*long_suspend*/true); |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 594 | // TODO We need to invalidate all breakpoints in the redefined class with the debugger. |
| 595 | // TODO We need to deal with any instrumentation/debugger deoptimized_methods_. |
| 596 | // TODO We need to update all debugger MethodIDs so they note the method they point to is |
| 597 | // obsolete or implement some other well defined semantics. |
| 598 | // TODO We need to decide on & implement semantics for JNI jmethodids when we redefine methods. |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 599 | // TODO Might want to move this into a different type. |
| 600 | // Now we reach the part where we must do active cleanup if something fails. |
| 601 | // TODO We should really Retry if this fails instead of simply aborting. |
| 602 | // Set the new DexFileCookie returns the original so we can fix it back up if redefinition fails |
| 603 | art::ObjPtr<art::mirror::LongArray> original_dex_file_cookie(nullptr); |
| 604 | if (!UpdateJavaDexFile(java_dex_file.Get(), |
| 605 | new_dex_file_cookie.Get(), |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 606 | &original_dex_file_cookie) || |
| 607 | !FindAndAllocateObsoleteMethods(art_class.Get())) { |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 608 | // Release suspendAll |
| 609 | runtime_->GetThreadList()->ResumeAll(); |
| 610 | // Get back shared mutator lock as expected for return. |
| 611 | self_->TransitionFromSuspendedToRunnable(); |
Alex Light | 6abd539 | 2017-01-05 17:53:00 -0800 | [diff] [blame^] | 612 | if (heap->IsGcConcurrentAndMoving()) { |
| 613 | heap->DecrementDisableMovingGC(self_); |
| 614 | } |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 615 | return result_; |
| 616 | } |
| 617 | if (!UpdateClass(art_class.Get(), new_dex_cache.Get())) { |
| 618 | // TODO Should have some form of scope to do this. |
| 619 | RestoreJavaDexFile(java_dex_file.Get(), original_dex_file_cookie); |
| 620 | // Release suspendAll |
| 621 | runtime_->GetThreadList()->ResumeAll(); |
| 622 | // Get back shared mutator lock as expected for return. |
| 623 | self_->TransitionFromSuspendedToRunnable(); |
Alex Light | 6abd539 | 2017-01-05 17:53:00 -0800 | [diff] [blame^] | 624 | if (heap->IsGcConcurrentAndMoving()) { |
| 625 | heap->DecrementDisableMovingGC(self_); |
| 626 | } |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 627 | return result_; |
| 628 | } |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 629 | // Ensure that obsolete methods are deoptimized. This is needed since optimized methods may have |
| 630 | // pointers to their ArtMethod's stashed in registers that they then use to attempt to hit the |
| 631 | // DexCache. |
| 632 | // TODO This can fail (leave some methods optimized) near runtime methods (including |
| 633 | // quick-to-interpreter transition function). |
| 634 | // TODO We probably don't need this at all once we have a way to ensure that the |
| 635 | // current_art_method is never stashed in a (physical) register by the JIT and lost to the |
| 636 | // stack-walker. |
| 637 | EnsureObsoleteMethodsAreDeoptimized(); |
| 638 | // TODO Verify the new Class. |
| 639 | // TODO Failure then undo updates to class |
| 640 | // TODO Shrink the obsolete method maps if possible? |
| 641 | // TODO find appropriate class loader. |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 642 | // TODO Put this into a scoped thing. |
| 643 | runtime_->GetThreadList()->ResumeAll(); |
| 644 | // Get back shared mutator lock as expected for return. |
| 645 | self_->TransitionFromSuspendedToRunnable(); |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 646 | // TODO Do the dex_file_ release at a more reasonable place. This works but it muddles who really |
| 647 | // owns the DexFile. |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 648 | dex_file_.release(); |
Alex Light | 6abd539 | 2017-01-05 17:53:00 -0800 | [diff] [blame^] | 649 | if (heap->IsGcConcurrentAndMoving()) { |
| 650 | heap->DecrementDisableMovingGC(self_); |
| 651 | } |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 652 | return OK; |
| 653 | } |
| 654 | |
| 655 | void Redefiner::RestoreJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file, |
| 656 | art::ObjPtr<art::mirror::LongArray> orig_cookie) { |
| 657 | art::ArtField* internal_cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField( |
| 658 | "mInternalCookie", "Ljava/lang/Object;"); |
| 659 | art::ArtField* cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField( |
| 660 | "mCookie", "Ljava/lang/Object;"); |
| 661 | art::ObjPtr<art::mirror::LongArray> new_cookie( |
| 662 | cookie_field->GetObject(java_dex_file)->AsLongArray()); |
| 663 | internal_cookie_field->SetObject<false>(java_dex_file, orig_cookie); |
| 664 | if (!new_cookie.IsNull()) { |
| 665 | cookie_field->SetObject<false>(java_dex_file, orig_cookie); |
| 666 | } |
| 667 | } |
| 668 | |
Alex Light | 200b9d7 | 2016-12-15 11:34:13 -0800 | [diff] [blame] | 669 | bool Redefiner::UpdateMethods(art::ObjPtr<art::mirror::Class> mclass, |
| 670 | art::ObjPtr<art::mirror::DexCache> new_dex_cache, |
| 671 | const art::DexFile::ClassDef& class_def) { |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 672 | art::ClassLinker* linker = runtime_->GetClassLinker(); |
| 673 | art::PointerSize image_pointer_size = linker->GetImagePointerSize(); |
Alex Light | 200b9d7 | 2016-12-15 11:34:13 -0800 | [diff] [blame] | 674 | const art::DexFile::TypeId& declaring_class_id = dex_file_->GetTypeId(class_def.class_idx_); |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 675 | const art::DexFile& old_dex_file = mclass->GetDexFile(); |
Alex Light | 200b9d7 | 2016-12-15 11:34:13 -0800 | [diff] [blame] | 676 | // Update methods. |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 677 | for (art::ArtMethod& method : mclass->GetMethods(image_pointer_size)) { |
| 678 | const art::DexFile::StringId* new_name_id = dex_file_->FindStringId(method.GetName()); |
| 679 | art::dex::TypeIndex method_return_idx = |
| 680 | dex_file_->GetIndexForTypeId(*dex_file_->FindTypeId(method.GetReturnTypeDescriptor())); |
| 681 | const auto* old_type_list = method.GetParameterTypeList(); |
| 682 | std::vector<art::dex::TypeIndex> new_type_list; |
| 683 | for (uint32_t i = 0; old_type_list != nullptr && i < old_type_list->Size(); i++) { |
| 684 | new_type_list.push_back( |
| 685 | dex_file_->GetIndexForTypeId( |
| 686 | *dex_file_->FindTypeId( |
| 687 | old_dex_file.GetTypeDescriptor( |
| 688 | old_dex_file.GetTypeId( |
| 689 | old_type_list->GetTypeItem(i).type_idx_))))); |
| 690 | } |
| 691 | const art::DexFile::ProtoId* proto_id = dex_file_->FindProtoId(method_return_idx, |
| 692 | new_type_list); |
Nicolas Geoffray | f6abcda | 2016-12-21 09:26:18 +0000 | [diff] [blame] | 693 | // TODO Return false, cleanup. |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 694 | CHECK(proto_id != nullptr || old_type_list == nullptr); |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 695 | const art::DexFile::MethodId* method_id = dex_file_->FindMethodId(declaring_class_id, |
| 696 | *new_name_id, |
| 697 | *proto_id); |
Nicolas Geoffray | f6abcda | 2016-12-21 09:26:18 +0000 | [diff] [blame] | 698 | // TODO Return false, cleanup. |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 699 | CHECK(method_id != nullptr); |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 700 | uint32_t dex_method_idx = dex_file_->GetIndexForMethodId(*method_id); |
| 701 | method.SetDexMethodIndex(dex_method_idx); |
| 702 | linker->SetEntryPointsToInterpreter(&method); |
Alex Light | 200b9d7 | 2016-12-15 11:34:13 -0800 | [diff] [blame] | 703 | method.SetCodeItemOffset(dex_file_->FindCodeItemOffset(class_def, dex_method_idx)); |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 704 | method.SetDexCacheResolvedMethods(new_dex_cache->GetResolvedMethods(), image_pointer_size); |
| 705 | method.SetDexCacheResolvedTypes(new_dex_cache->GetResolvedTypes(), image_pointer_size); |
Alex Light | dba6148 | 2016-12-21 08:20:29 -0800 | [diff] [blame] | 706 | // Notify the jit that this method is redefined. |
| 707 | art::jit::Jit* jit = runtime_->GetJit(); |
| 708 | if (jit != nullptr) { |
| 709 | jit->GetCodeCache()->NotifyMethodRedefined(&method); |
| 710 | } |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 711 | } |
Alex Light | 200b9d7 | 2016-12-15 11:34:13 -0800 | [diff] [blame] | 712 | return true; |
| 713 | } |
| 714 | |
| 715 | bool Redefiner::UpdateFields(art::ObjPtr<art::mirror::Class> mclass) { |
| 716 | // TODO The IFields & SFields pointers should be combined like the methods_ arrays were. |
| 717 | for (auto fields_iter : {mclass->GetIFields(), mclass->GetSFields()}) { |
| 718 | for (art::ArtField& field : fields_iter) { |
| 719 | std::string declaring_class_name; |
| 720 | const art::DexFile::TypeId* new_declaring_id = |
| 721 | dex_file_->FindTypeId(field.GetDeclaringClass()->GetDescriptor(&declaring_class_name)); |
| 722 | const art::DexFile::StringId* new_name_id = dex_file_->FindStringId(field.GetName()); |
| 723 | const art::DexFile::TypeId* new_type_id = dex_file_->FindTypeId(field.GetTypeDescriptor()); |
| 724 | // TODO Handle error, cleanup. |
| 725 | CHECK(new_name_id != nullptr && new_type_id != nullptr && new_declaring_id != nullptr); |
| 726 | const art::DexFile::FieldId* new_field_id = |
| 727 | dex_file_->FindFieldId(*new_declaring_id, *new_name_id, *new_type_id); |
| 728 | CHECK(new_field_id != nullptr); |
| 729 | // We only need to update the index since the other data in the ArtField cannot be updated. |
| 730 | field.SetDexFieldIndex(dex_file_->GetIndexForFieldId(*new_field_id)); |
| 731 | } |
| 732 | } |
| 733 | return true; |
| 734 | } |
| 735 | |
| 736 | // Performs updates to class that will allow us to verify it. |
| 737 | bool Redefiner::UpdateClass(art::ObjPtr<art::mirror::Class> mclass, |
| 738 | art::ObjPtr<art::mirror::DexCache> new_dex_cache) { |
| 739 | const art::DexFile::ClassDef* class_def = art::OatFile::OatDexFile::FindClassDef( |
| 740 | *dex_file_, class_sig_, art::ComputeModifiedUtf8Hash(class_sig_)); |
| 741 | if (class_def == nullptr) { |
| 742 | RecordFailure(ERR(INVALID_CLASS_FORMAT), "Unable to find ClassDef!"); |
| 743 | return false; |
| 744 | } |
| 745 | if (!UpdateMethods(mclass, new_dex_cache, *class_def)) { |
| 746 | // TODO Investigate appropriate error types. |
| 747 | RecordFailure(ERR(INTERNAL), "Unable to update class methods."); |
| 748 | return false; |
| 749 | } |
| 750 | if (!UpdateFields(mclass)) { |
| 751 | // TODO Investigate appropriate error types. |
| 752 | RecordFailure(ERR(INTERNAL), "Unable to update class fields."); |
| 753 | return false; |
| 754 | } |
| 755 | |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 756 | // Update the class fields. |
| 757 | // Need to update class last since the ArtMethod gets its DexFile from the class (which is needed |
| 758 | // to call GetReturnTypeDescriptor and GetParameterTypeList above). |
| 759 | mclass->SetDexCache(new_dex_cache.Ptr()); |
Alex Light | a01de59 | 2016-11-15 10:43:06 -0800 | [diff] [blame] | 760 | mclass->SetDexClassDefIndex(dex_file_->GetIndexForClassDef(*class_def)); |
| 761 | mclass->SetDexTypeIndex(dex_file_->GetIndexForTypeId(*dex_file_->FindTypeId(class_sig_))); |
| 762 | return true; |
| 763 | } |
| 764 | |
| 765 | bool Redefiner::UpdateJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file, |
| 766 | art::ObjPtr<art::mirror::LongArray> new_cookie, |
| 767 | /*out*/art::ObjPtr<art::mirror::LongArray>* original_cookie) { |
| 768 | art::ArtField* internal_cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField( |
| 769 | "mInternalCookie", "Ljava/lang/Object;"); |
| 770 | art::ArtField* cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField( |
| 771 | "mCookie", "Ljava/lang/Object;"); |
| 772 | CHECK(internal_cookie_field != nullptr); |
| 773 | art::ObjPtr<art::mirror::LongArray> orig_internal_cookie( |
| 774 | internal_cookie_field->GetObject(java_dex_file)->AsLongArray()); |
| 775 | art::ObjPtr<art::mirror::LongArray> orig_cookie( |
| 776 | cookie_field->GetObject(java_dex_file)->AsLongArray()); |
| 777 | internal_cookie_field->SetObject<false>(java_dex_file, new_cookie); |
| 778 | *original_cookie = orig_internal_cookie; |
| 779 | if (!orig_cookie.IsNull()) { |
| 780 | cookie_field->SetObject<false>(java_dex_file, new_cookie); |
| 781 | } |
| 782 | return true; |
| 783 | } |
| 784 | |
| 785 | // This function does all (java) allocations we need to do for the Class being redefined. |
| 786 | // TODO Change this name maybe? |
| 787 | bool Redefiner::EnsureClassAllocationsFinished() { |
| 788 | art::StackHandleScope<2> hs(self_); |
| 789 | art::Handle<art::mirror::Class> klass(hs.NewHandle(self_->DecodeJObject(klass_)->AsClass())); |
| 790 | if (klass.Get() == nullptr) { |
| 791 | RecordFailure(ERR(INVALID_CLASS), "Unable to decode class argument!"); |
| 792 | return false; |
| 793 | } |
| 794 | // Allocate the classExt |
| 795 | art::Handle<art::mirror::ClassExt> ext(hs.NewHandle(klass->EnsureExtDataPresent(self_))); |
| 796 | if (ext.Get() == nullptr) { |
| 797 | // No memory. Clear exception (it's not useful) and return error. |
| 798 | // TODO This doesn't need to be fatal. We could just not support obsolete methods after hitting |
| 799 | // this case. |
| 800 | self_->AssertPendingOOMException(); |
| 801 | self_->ClearException(); |
| 802 | RecordFailure(ERR(OUT_OF_MEMORY), "Could not allocate ClassExt"); |
| 803 | return false; |
| 804 | } |
| 805 | // Allocate the 2 arrays that make up the obsolete methods map. Since the contents of the arrays |
| 806 | // are only modified when all threads (other than the modifying one) are suspended we don't need |
| 807 | // to worry about missing the unsyncronized writes to the array. We do synchronize when setting it |
| 808 | // however, since that can happen at any time. |
| 809 | // TODO Clear these after we walk the stacks in order to free them in the (likely?) event there |
| 810 | // are no obsolete methods. |
| 811 | { |
| 812 | art::ObjectLock<art::mirror::ClassExt> lock(self_, ext); |
| 813 | if (!ext->ExtendObsoleteArrays( |
| 814 | self_, klass->GetDeclaredMethodsSlice(art::kRuntimePointerSize).size())) { |
| 815 | // OOM. Clear exception and return error. |
| 816 | self_->AssertPendingOOMException(); |
| 817 | self_->ClearException(); |
| 818 | RecordFailure(ERR(OUT_OF_MEMORY), "Unable to allocate/extend obsolete methods map"); |
| 819 | return false; |
| 820 | } |
| 821 | } |
| 822 | return true; |
| 823 | } |
| 824 | |
| 825 | } // namespace openjdkjvmti |