// Copyright 2018 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #include "include/v8-template.h" #include "src/api/api-inl.h" #include "src/debug/debug.h" #include "src/execution/frames-inl.h" #include "src/flags/flags.h" #include "src/heap/read-only-spaces.h" #include "test/cctest/cctest.h" #include "tools/debug_helper/debug-helper.h" namespace v8 { namespace internal { namespace { namespace d = v8::debug_helper; uintptr_t memory_fail_start = 0; uintptr_t memory_fail_end = 0; class MemoryFailureRegion { public: MemoryFailureRegion(uintptr_t start, uintptr_t end) { memory_fail_start = start; memory_fail_end = end; } ~MemoryFailureRegion() { memory_fail_start = 0; memory_fail_end = 0; } }; // Implement the memory-reading callback. This one just fetches memory from the // current process, but a real implementation for a debugging extension would // fetch memory from the debuggee process or crash dump. d::MemoryAccessResult ReadMemory(uintptr_t address, void* destination, size_t byte_count) { if (address >= memory_fail_start && address <= memory_fail_end) { // Simulate failure to read debuggee memory. return d::MemoryAccessResult::kAddressValidButInaccessible; } memcpy(destination, reinterpret_cast(address), byte_count); return d::MemoryAccessResult::kOk; } void CheckPropBase(const d::PropertyBase& property, const char* expected_type, const char* expected_name) { CHECK(property.type == std::string("v8::internal::TaggedValue") || property.type == std::string(expected_type)); CHECK(property.decompressed_type == std::string(expected_type)); CHECK(property.name == std::string(expected_name)); } void CheckProp(const d::ObjectProperty& property, const char* expected_type, const char* expected_name, d::PropertyKind expected_kind = d::PropertyKind::kSingle, size_t expected_num_values = 1) { CheckPropBase(property, expected_type, expected_name); CHECK_EQ(property.num_values, expected_num_values); CHECK(property.kind == expected_kind); } template void CheckProp(const d::ObjectProperty& property, const char* expected_type, const char* expected_name, TValue expected_value) { CheckProp(property, expected_type, expected_name); CHECK(*reinterpret_cast(property.address) == expected_value); } bool StartsWith(const std::string& full_string, const std::string& prefix) { return full_string.substr(0, prefix.size()) == prefix; } bool Contains(const std::string& full_string, const std::string& substr) { return full_string.find(substr) != std::string::npos; } void CheckStructProp(const d::StructProperty& property, const char* expected_type, const char* expected_name, size_t expected_offset, uint8_t expected_num_bits = 0, uint8_t expected_shift_bits = 0) { CheckPropBase(property, expected_type, expected_name); CHECK_EQ(property.offset, expected_offset); CHECK_EQ(property.num_bits, expected_num_bits); CHECK_EQ(property.shift_bits, expected_shift_bits); } const d::ObjectProperty& FindProp(const d::ObjectPropertiesResult& props, std::string name) { for (size_t i = 0; i < props.num_properties; ++i) { if (name == props.properties[i]->name) { return *props.properties[i]; } } CHECK_WITH_MSG(false, ("property '" + name + "' not found").c_str()); UNREACHABLE(); } template TValue ReadProp(const d::ObjectPropertiesResult& props, std::string name) { const d::ObjectProperty& prop = FindProp(props, name); return *reinterpret_cast(prop.address); } // A simple implementation of ExternalStringResource that lets us control the // result of IsCacheable(). class StringResource : public v8::String::ExternalStringResource { public: explicit StringResource(bool cacheable) : cacheable_(cacheable) {} const uint16_t* data() const override { return reinterpret_cast(u"abcde"); } size_t length() const override { return 5; } bool IsCacheable() const override { return cacheable_; } private: bool cacheable_; }; } // namespace TEST(GetObjectProperties) { CcTest::InitializeVM(); v8::Isolate* isolate = CcTest::isolate(); i::Isolate* i_isolate = reinterpret_cast(isolate); v8::HandleScope scope(isolate); LocalContext context; // Claim we don't know anything about the heap layout. d::HeapAddresses heap_addresses{0, 0, 0, 0}; v8::Local v = CompileRun("42"); Handle o = v8::Utils::OpenHandle(*v); d::ObjectPropertiesResultPtr props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); CHECK(props->type_check_result == d::TypeCheckResult::kSmi); CHECK(props->brief == std::string("42 (0x2a)")); CHECK(props->type == std::string("v8::internal::Smi")); CHECK_EQ(props->num_properties, 0); v = CompileRun("[\"a\", \"bc\"]"); o = v8::Utils::OpenHandle(*v); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); CHECK(props->type_check_result == d::TypeCheckResult::kUsedMap); CHECK(props->type == std::string("v8::internal::JSArray")); CHECK_EQ(props->num_properties, 4); CheckProp(*props->properties[0], "v8::internal::Map", "map"); CheckProp(*props->properties[1], "v8::internal::Object", "properties_or_hash"); CheckProp(*props->properties[2], "v8::internal::FixedArrayBase", "elements"); CheckProp(*props->properties[3], "v8::internal::Object", "length", static_cast(IntToSmi(2))); // We need to supply some valid address for decompression before reading the // elements from the JSArray. heap_addresses.any_heap_pointer = o->ptr(); i::Tagged_t properties_or_hash = *reinterpret_cast(props->properties[1]->address); i::Tagged_t elements = *reinterpret_cast(props->properties[2]->address); // The properties_or_hash_code field should be an empty fixed array. Since // that is at a known offset, we should be able to detect it even without // any ability to read memory. { MemoryFailureRegion failure(0, UINTPTR_MAX); props = d::GetObjectProperties(properties_or_hash, &ReadMemory, heap_addresses); CHECK(props->type_check_result == d::TypeCheckResult::kObjectPointerValidButInaccessible); CHECK(props->type == std::string("v8::internal::HeapObject")); CHECK_EQ(props->num_properties, 1); CheckProp(*props->properties[0], "v8::internal::Map", "map"); // "maybe" prefix indicates that GetObjectProperties recognized the offset // within the page as matching a known object, but didn't know whether the // object is on the right page. This response can only happen in builds // without pointer compression, because otherwise heap addresses would be at // deterministic locations within the heap reservation. CHECK(COMPRESS_POINTERS_BOOL ? StartsWith(props->brief, "EmptyFixedArray") : Contains(props->brief, "maybe EmptyFixedArray")); // Provide a heap first page so the API can be more sure. heap_addresses.read_only_space_first_page = i_isolate->heap()->read_only_space()->FirstPageAddress(); props = d::GetObjectProperties(properties_or_hash, &ReadMemory, heap_addresses); CHECK(props->type_check_result == d::TypeCheckResult::kObjectPointerValidButInaccessible); CHECK(props->type == std::string("v8::internal::HeapObject")); CHECK_EQ(props->num_properties, 1); CheckProp(*props->properties[0], "v8::internal::Map", "map"); CHECK(StartsWith(props->brief, "EmptyFixedArray")); } props = d::GetObjectProperties(elements, &ReadMemory, heap_addresses); CHECK(props->type_check_result == d::TypeCheckResult::kUsedMap); CHECK(props->type == std::string("v8::internal::FixedArray")); CHECK_EQ(props->num_properties, 3); CheckProp(*props->properties[0], "v8::internal::Map", "map"); CheckProp(*props->properties[1], "v8::internal::Object", "length", static_cast(IntToSmi(2))); CheckProp(*props->properties[2], "v8::internal::Object", "objects", d::PropertyKind::kArrayOfKnownSize, 2); // Get the second string value from the FixedArray. i::Tagged_t second_string_address = reinterpret_cast(props->properties[2]->address)[1]; props = d::GetObjectProperties(second_string_address, &ReadMemory, heap_addresses); CHECK(props->type_check_result == d::TypeCheckResult::kUsedMap); CHECK(props->type == std::string("v8::internal::SeqOneByteString")); CHECK_EQ(props->num_properties, 4); CheckProp(*props->properties[0], "v8::internal::Map", "map"); CheckProp(*props->properties[1], "uint32_t", "raw_hash_field"); CheckProp(*props->properties[2], "int32_t", "length", 2); CheckProp(*props->properties[3], "char", "chars", d::PropertyKind::kArrayOfKnownSize, 2); CHECK_EQ( strncmp("bc", reinterpret_cast(props->properties[3]->address), 2), 0); // Read the second string again, using a type hint instead of the map. All of // its properties should match what we read last time. d::ObjectPropertiesResultPtr props2; { d::HeapAddresses heap_addresses_without_ro_space = heap_addresses; heap_addresses_without_ro_space.read_only_space_first_page = 0; uintptr_t map_ptr = props->properties[0]->address; uintptr_t map_map_ptr = *reinterpret_cast(map_ptr); #if V8_MAP_PACKING map_map_ptr = reinterpret_cast(&map_map_ptr)->ToMap().ptr(); #endif uintptr_t map_address = d::GetObjectProperties(map_map_ptr, &ReadMemory, heap_addresses_without_ro_space) ->properties[0] ->address; MemoryFailureRegion failure(map_address, map_address + i::Map::kSize); props2 = d::GetObjectProperties(second_string_address, &ReadMemory, heap_addresses_without_ro_space, "v8::internal::String"); if (COMPRESS_POINTERS_BOOL) { // The first page of each heap space can be automatically detected when // pointer compression is active, so we expect to use known maps instead // of the type hint. CHECK_EQ(props2->type_check_result, d::TypeCheckResult::kKnownMapPointer); CHECK(props2->type == std::string("v8::internal::SeqOneByteString")); CHECK_EQ(props2->num_properties, 4); CheckProp(*props2->properties[3], "char", "chars", d::PropertyKind::kArrayOfKnownSize, 2); CHECK_EQ(props2->num_guessed_types, 0); } else { CHECK_EQ(props2->type_check_result, d::TypeCheckResult::kUsedTypeHint); CHECK(props2->type == std::string("v8::internal::String")); CHECK_EQ(props2->num_properties, 3); // The type hint we provided was the abstract class String, but // GetObjectProperties should have recognized that the Map pointer looked // like the right value for a SeqOneByteString. CHECK_EQ(props2->num_guessed_types, 1); CHECK(std::string(props2->guessed_types[0]) == std::string("v8::internal::SeqOneByteString")); } CheckProp(*props2->properties[0], "v8::internal::Map", "map", *reinterpret_cast(props->properties[0]->address)); CheckProp(*props2->properties[1], "uint32_t", "raw_hash_field", *reinterpret_cast(props->properties[1]->address)); CheckProp(*props2->properties[2], "int32_t", "length", 2); } // Try a weak reference. props2 = d::GetObjectProperties(second_string_address | kWeakHeapObjectMask, &ReadMemory, heap_addresses); std::string weak_ref_prefix = "weak ref to "; CHECK(weak_ref_prefix + props->brief == props2->brief); CHECK(props2->type_check_result == d::TypeCheckResult::kUsedMap); CHECK(props2->type == std::string("v8::internal::SeqOneByteString")); CHECK_EQ(props2->num_properties, 4); CheckProp(*props2->properties[0], "v8::internal::Map", "map", *reinterpret_cast(props->properties[0]->address)); CheckProp(*props2->properties[1], "uint32_t", "raw_hash_field", *reinterpret_cast(props->properties[1]->address)); CheckProp(*props2->properties[2], "int32_t", "length", 2); // Build a complicated string (multi-level cons with slices inside) to test // string printing. v = CompileRun(R"( const alphabet = "abcdefghijklmnopqrstuvwxyz"; alphabet.substr(3,20) + alphabet.toUpperCase().substr(5,15) + "7")"); o = v8::Utils::OpenHandle(*v); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); CHECK(Contains(props->brief, "\"defghijklmnopqrstuvwFGHIJKLMNOPQRST7\"")); // Cause a failure when reading the "second" pointer within the top-level // ConsString. { CheckProp(*props->properties[4], "v8::internal::String", "second"); uintptr_t second_address = props->properties[4]->address; MemoryFailureRegion failure(second_address, second_address + 4); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); CHECK(Contains(props->brief, "\"defghijklmnopqrstuvwFGHIJKLMNOPQRST...\"")); } // Build a very long string. v = CompileRun("'a'.repeat(1000)"); o = v8::Utils::OpenHandle(*v); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); CHECK(Contains(props->brief, "\"" + std::string(80, 'a') + "...\"")); // GetObjectProperties can read cacheable external strings. auto external_string = v8::String::NewExternalTwoByte(isolate, new StringResource(true)); o = v8::Utils::OpenHandle(*external_string.ToLocalChecked()); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); CHECK(Contains(props->brief, "\"abcde\"")); // GetObjectProperties cannot read uncacheable external strings. external_string = v8::String::NewExternalTwoByte(isolate, new StringResource(false)); o = v8::Utils::OpenHandle(*external_string.ToLocalChecked()); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); CHECK_EQ(std::string(props->brief).find("\""), std::string::npos); // Build a basic JS object and get its properties. v = CompileRun("({a: 1, b: 2})"); o = v8::Utils::OpenHandle(*v); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); // Objects constructed from literals get their properties placed inline, so // the GetObjectProperties response should include an array. const d::ObjectProperty& prop = FindProp(*props, "in-object properties"); CheckProp(prop, "v8::internal::Object", "in-object properties", d::PropertyKind::kArrayOfKnownSize, 2); // The second item in that array is the SMI value 2 from the object literal. props2 = d::GetObjectProperties(reinterpret_cast(prop.address)[1], &ReadMemory, heap_addresses); CHECK(props2->brief == std::string("2 (0x2)")); // Verify the result for a heap object field which is itself a struct: the // "descriptors" field on a DescriptorArray. // Start by getting the object's map and the map's descriptor array. uintptr_t map_ptr = ReadProp(*props, "map"); #if V8_MAP_PACKING map_ptr = reinterpret_cast(&map_ptr)->ToMap().ptr(); #endif props = d::GetObjectProperties(map_ptr, &ReadMemory, heap_addresses); props = d::GetObjectProperties( ReadProp(*props, "instance_descriptors"), &ReadMemory, heap_addresses); // It should have at least two descriptors (possibly plus slack). CheckProp(*props->properties[1], "uint16_t", "number_of_all_descriptors"); uint16_t number_of_all_descriptors = *reinterpret_cast(props->properties[1]->address); CHECK_GE(number_of_all_descriptors, 2); // The "descriptors" property should describe the struct layout for each // element in the array. const d::ObjectProperty& descriptors = *props->properties[6]; // No C++ type is reported directly because there may not be an actual C++ // struct with this layout, hence the empty string in this check. CheckProp(descriptors, /*type=*/"", "descriptors", d::PropertyKind::kArrayOfKnownSize, number_of_all_descriptors); CHECK_EQ(descriptors.size, 3 * i::kTaggedSize); CHECK_EQ(descriptors.num_struct_fields, 3); CheckStructProp(*descriptors.struct_fields[0], "v8::internal::PrimitiveHeapObject", "key", 0 * i::kTaggedSize); CheckStructProp(*descriptors.struct_fields[1], "v8::internal::Object", "details", 1 * i::kTaggedSize); CheckStructProp(*descriptors.struct_fields[2], "v8::internal::Object", "value", 2 * i::kTaggedSize); // Build a basic JS function and get its properties. This will allow us to // exercise bitfield functionality. v = CompileRun("(function () {})"); o = v8::Utils::OpenHandle(*v); props = d::GetObjectProperties(o->ptr(), &ReadMemory, heap_addresses); props = d::GetObjectProperties( ReadProp(*props, "shared_function_info"), &ReadMemory, heap_addresses); const d::ObjectProperty& flags = FindProp(*props, "flags"); CHECK_GE(flags.num_struct_fields, 3); CheckStructProp(*flags.struct_fields[0], "FunctionKind", "function_kind", 0, 5, 0); CheckStructProp(*flags.struct_fields[1], "bool", "is_native", 0, 1, 5); CheckStructProp(*flags.struct_fields[2], "bool", "is_strict", 0, 1, 6); // Get data about a different bitfield struct which is contained within a smi. Handle function = Handle::cast(o); Handle shared(function->shared(), i_isolate); Handle debug_info = i_isolate->debug()->GetOrCreateDebugInfo(shared); props = d::GetObjectProperties(debug_info->ptr(), &ReadMemory, heap_addresses); const d::ObjectProperty& debug_flags = FindProp(*props, "flags"); CHECK_GE(debug_flags.num_struct_fields, 5); CheckStructProp(*debug_flags.struct_fields[0], "bool", "has_break_info", 0, 1, i::kSmiTagSize + i::kSmiShiftSize); CheckStructProp(*debug_flags.struct_fields[4], "bool", "can_break_at_entry", 0, 1, i::kSmiTagSize + i::kSmiShiftSize + 4); } TEST(ListObjectClasses) { CcTest::InitializeVM(); // The ListObjectClasses result will change as classes are added, removed, or // renamed. Just check that a few expected classes are included in the list, // and that there are no duplicates. const d::ClassList* class_list = d::ListObjectClasses(); std::unordered_set class_set; for (size_t i = 0; i < class_list->num_class_names; ++i) { CHECK_WITH_MSG(class_set.insert(class_list->class_names[i]).second, "there should be no duplicate entries"); } CHECK_NE(class_set.find("v8::internal::HeapObject"), class_set.end()); CHECK_NE(class_set.find("v8::internal::String"), class_set.end()); CHECK_NE(class_set.find("v8::internal::JSRegExp"), class_set.end()); } static void FrameIterationCheck( v8::Local name, const v8::PropertyCallbackInfo& info) { i::StackFrameIterator iter(reinterpret_cast(info.GetIsolate())); for (int i = 0; !iter.done(); i++) { i::StackFrame* frame = iter.frame(); CHECK(i != 0 || (frame->type() == i::StackFrame::EXIT)); d::StackFrameResultPtr props = d::GetStackFrame(frame->fp(), &ReadMemory); if (frame->is_java_script()) { JavaScriptFrame* js_frame = JavaScriptFrame::cast(frame); CHECK_EQ(props->num_properties, 5); auto js_function = js_frame->function(); CheckProp(*props->properties[0], "v8::internal::JSFunction", "currently_executing_jsfunction", js_function.ptr()); auto shared_function_info = js_function.shared(); auto script = i::Script::cast(shared_function_info.script()); CheckProp(*props->properties[1], "v8::internal::Object", "script_name", static_cast(script.name().ptr())); CheckProp(*props->properties[2], "v8::internal::Object", "script_source", static_cast(script.source().ptr())); auto scope_info = shared_function_info.scope_info(); CheckProp(*props->properties[3], "v8::internal::Object", "function_name", static_cast(scope_info.FunctionName().ptr())); CheckProp(*props->properties[4], "", "function_character_offset"); const d::ObjectProperty& function_character_offset = *props->properties[4]; CHECK_EQ(function_character_offset.num_struct_fields, 2); CheckStructProp(*function_character_offset.struct_fields[0], "v8::internal::Object", "start", 0); CheckStructProp(*function_character_offset.struct_fields[1], "v8::internal::Object", "end", 4); } else { CHECK_EQ(props->num_properties, 0); } iter.Advance(); } } THREADED_TEST(GetFrameStack) { LocalContext env; v8::Isolate* isolate = env->GetIsolate(); v8::HandleScope scope(isolate); v8::Local obj = v8::ObjectTemplate::New(isolate); obj->SetAccessor(v8_str("xxx"), FrameIterationCheck); CHECK(env->Global() ->Set(env.local(), v8_str("obj"), obj->NewInstance(env.local()).ToLocalChecked()) .FromJust()); v8::Script::Compile(env.local(), v8_str("function foo() {" " return obj.xxx;" "}" "foo();")) .ToLocalChecked() ->Run(env.local()) .ToLocalChecked(); } TEST(SmallOrderedHashSetGetObjectProperties) { LocalContext context; Isolate* isolate = reinterpret_cast((*context)->GetIsolate()); Factory* factory = isolate->factory(); HandleScope scope(isolate); Handle set = factory->NewSmallOrderedHashSet(); const size_t number_of_buckets = 2; CHECK_EQ(number_of_buckets, set->NumberOfBuckets()); CHECK_EQ(0, set->NumberOfElements()); // Verify with the definition of SmallOrderedHashSet in // src\objects\ordered-hash-table.tq. d::HeapAddresses heap_addresses{0, 0, 0, 0}; d::ObjectPropertiesResultPtr props = d::GetObjectProperties(set->ptr(), &ReadMemory, heap_addresses); CHECK_EQ(props->type_check_result, d::TypeCheckResult::kUsedMap); CHECK_EQ(props->type, std::string("v8::internal::SmallOrderedHashSet")); CHECK_EQ(props->num_properties, 8); CheckProp(*props->properties[0], "v8::internal::Map", "map"); CheckProp(*props->properties[1], "uint8_t", "number_of_elements"); CheckProp(*props->properties[2], "uint8_t", "number_of_deleted_elements"); CheckProp(*props->properties[3], "uint8_t", "number_of_buckets"); #if TAGGED_SIZE_8_BYTES CheckProp(*props->properties[4], "uint8_t", "padding", d::PropertyKind::kArrayOfKnownSize, 5); #else CheckProp(*props->properties[4], "uint8_t", "padding", d::PropertyKind::kArrayOfKnownSize, 1); #endif CheckProp(*props->properties[5], "v8::internal::Object", "data_table", d::PropertyKind::kArrayOfKnownSize, number_of_buckets * OrderedHashMap::kLoadFactor); CheckProp(*props->properties[6], "uint8_t", "hash_table", d::PropertyKind::kArrayOfKnownSize, number_of_buckets); CheckProp(*props->properties[7], "uint8_t", "chain_table", d::PropertyKind::kArrayOfKnownSize, number_of_buckets * OrderedHashMap::kLoadFactor); } } // namespace internal } // namespace v8