| //===-- DynamicLoaderMacOS.cpp --------------------------------------------===// | |
| // | |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | |
| // See https://llvm.org/LICENSE.txt for license information. | |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | |
| // | |
| //===----------------------------------------------------------------------===// | |
| #include "lldb/Breakpoint/StoppointCallbackContext.h" | |
| #include "lldb/Core/Debugger.h" | |
| #include "lldb/Core/Module.h" | |
| #include "lldb/Core/PluginManager.h" | |
| #include "lldb/Core/Section.h" | |
| #include "lldb/Symbol/ObjectFile.h" | |
| #include "lldb/Symbol/SymbolVendor.h" | |
| #include "lldb/Target/ABI.h" | |
| #include "lldb/Target/SectionLoadList.h" | |
| #include "lldb/Target/StackFrame.h" | |
| #include "lldb/Target/Target.h" | |
| #include "lldb/Target/Thread.h" | |
| #include "lldb/Utility/LLDBLog.h" | |
| #include "lldb/Utility/Log.h" | |
| #include "lldb/Utility/State.h" | |
| #include "llvm/Support/Error.h" | |
| #include "DynamicLoaderDarwin.h" | |
| #include "DynamicLoaderMacOS.h" | |
| #include "Plugins/TypeSystem/Clang/TypeSystemClang.h" | |
| using namespace lldb; | |
| using namespace lldb_private; | |
| // Create an instance of this class. This function is filled into the plugin | |
| // info class that gets handed out by the plugin factory and allows the lldb to | |
| // instantiate an instance of this class. | |
| DynamicLoader *DynamicLoaderMacOS::CreateInstance(Process *process, | |
| bool force) { | |
| bool create = force; | |
| if (!create) { | |
| create = true; | |
| Module *exe_module = process->GetTarget().GetExecutableModulePointer(); | |
| if (exe_module) { | |
| ObjectFile *object_file = exe_module->GetObjectFile(); | |
| if (object_file) { | |
| create = (object_file->GetStrata() == ObjectFile::eStrataUser); | |
| } | |
| } | |
| if (create) { | |
| const llvm::Triple &triple_ref = | |
| process->GetTarget().GetArchitecture().GetTriple(); | |
| switch (triple_ref.getOS()) { | |
| case llvm::Triple::Darwin: | |
| case llvm::Triple::MacOSX: | |
| case llvm::Triple::IOS: | |
| case llvm::Triple::TvOS: | |
| case llvm::Triple::WatchOS: | |
| case llvm::Triple::BridgeOS: | |
| case llvm::Triple::DriverKit: | |
| case llvm::Triple::XROS: | |
| create = triple_ref.getVendor() == llvm::Triple::Apple; | |
| break; | |
| default: | |
| create = false; | |
| break; | |
| } | |
| } | |
| } | |
| if (!UseDYLDSPI(process)) { | |
| create = false; | |
| } | |
| if (create) | |
| return new DynamicLoaderMacOS(process); | |
| return nullptr; | |
| } | |
| // Constructor | |
| DynamicLoaderMacOS::DynamicLoaderMacOS(Process *process) | |
| : DynamicLoaderDarwin(process), m_image_infos_stop_id(UINT32_MAX), | |
| m_break_id(LLDB_INVALID_BREAK_ID), | |
| m_dyld_handover_break_id(LLDB_INVALID_BREAK_ID), m_mutex(), | |
| m_maybe_image_infos_address(LLDB_INVALID_ADDRESS), | |
| m_libsystem_fully_initalized(false) {} | |
| // Destructor | |
| DynamicLoaderMacOS::~DynamicLoaderMacOS() { | |
| if (LLDB_BREAK_ID_IS_VALID(m_break_id)) | |
| m_process->GetTarget().RemoveBreakpointByID(m_break_id); | |
| if (LLDB_BREAK_ID_IS_VALID(m_dyld_handover_break_id)) | |
| m_process->GetTarget().RemoveBreakpointByID(m_dyld_handover_break_id); | |
| } | |
| bool DynamicLoaderMacOS::ProcessDidExec() { | |
| std::lock_guard<std::recursive_mutex> baseclass_guard(GetMutex()); | |
| bool did_exec = false; | |
| if (m_process) { | |
| // If we are stopped after an exec, we will have only one thread... | |
| if (m_process->GetThreadList().GetSize() == 1) { | |
| // Maybe we still have an image infos address around? If so see | |
| // if that has changed, and if so we have exec'ed. | |
| if (m_maybe_image_infos_address != LLDB_INVALID_ADDRESS) { | |
| lldb::addr_t image_infos_address = m_process->GetImageInfoAddress(); | |
| if (image_infos_address != m_maybe_image_infos_address) { | |
| // We don't really have to reset this here, since we are going to | |
| // call DoInitialImageFetch right away to handle the exec. But in | |
| // case anybody looks at it in the meantime, it can't hurt. | |
| m_maybe_image_infos_address = image_infos_address; | |
| did_exec = true; | |
| } | |
| } | |
| if (!did_exec) { | |
| // See if we are stopped at '_dyld_start' | |
| ThreadSP thread_sp(m_process->GetThreadList().GetThreadAtIndex(0)); | |
| if (thread_sp) { | |
| lldb::StackFrameSP frame_sp(thread_sp->GetStackFrameAtIndex(0)); | |
| if (frame_sp) { | |
| const Symbol *symbol = | |
| frame_sp->GetSymbolContext(eSymbolContextSymbol).symbol; | |
| if (symbol) { | |
| if (symbol->GetName() == "_dyld_start") | |
| did_exec = true; | |
| } | |
| } | |
| } | |
| } | |
| } | |
| } | |
| if (did_exec) { | |
| m_libpthread_module_wp.reset(); | |
| m_pthread_getspecific_addr.Clear(); | |
| m_libsystem_fully_initalized = false; | |
| } | |
| return did_exec; | |
| } | |
| // Clear out the state of this class. | |
| void DynamicLoaderMacOS::DoClear() { | |
| std::lock_guard<std::recursive_mutex> guard(m_mutex); | |
| if (LLDB_BREAK_ID_IS_VALID(m_break_id)) | |
| m_process->GetTarget().RemoveBreakpointByID(m_break_id); | |
| if (LLDB_BREAK_ID_IS_VALID(m_dyld_handover_break_id)) | |
| m_process->GetTarget().RemoveBreakpointByID(m_dyld_handover_break_id); | |
| m_break_id = LLDB_INVALID_BREAK_ID; | |
| m_dyld_handover_break_id = LLDB_INVALID_BREAK_ID; | |
| m_libsystem_fully_initalized = false; | |
| } | |
| bool DynamicLoaderMacOS::IsFullyInitialized() { | |
| if (m_libsystem_fully_initalized) | |
| return true; | |
| StructuredData::ObjectSP process_state_sp( | |
| m_process->GetDynamicLoaderProcessState()); | |
| if (!process_state_sp) | |
| return true; | |
| if (process_state_sp->GetAsDictionary()->HasKey("error")) | |
| return true; | |
| if (!process_state_sp->GetAsDictionary()->HasKey("process_state string")) | |
| return true; | |
| std::string proc_state = process_state_sp->GetAsDictionary() | |
| ->GetValueForKey("process_state string") | |
| ->GetAsString() | |
| ->GetValue() | |
| .str(); | |
| if (proc_state == "dyld_process_state_not_started" || | |
| proc_state == "dyld_process_state_dyld_initialized" || | |
| proc_state == "dyld_process_state_terminated_before_inits") { | |
| return false; | |
| } | |
| m_libsystem_fully_initalized = true; | |
| return true; | |
| } | |
| // Check if we have found DYLD yet | |
| bool DynamicLoaderMacOS::DidSetNotificationBreakpoint() { | |
| return LLDB_BREAK_ID_IS_VALID(m_break_id); | |
| } | |
| void DynamicLoaderMacOS::ClearNotificationBreakpoint() { | |
| if (LLDB_BREAK_ID_IS_VALID(m_break_id)) { | |
| m_process->GetTarget().RemoveBreakpointByID(m_break_id); | |
| m_break_id = LLDB_INVALID_BREAK_ID; | |
| } | |
| } | |
| void DynamicLoaderMacOS::DoInitialImageFetch() { | |
| Log *log = GetLog(LLDBLog::DynamicLoader); | |
| // Remove any binaries we pre-loaded in the Target before | |
| // launching/attaching. If the same binaries are present in the process, | |
| // we'll get them from the shared module cache, we won't need to re-load them | |
| // from disk. | |
| UnloadAllImages(); | |
| StructuredData::ObjectSP all_image_info_json_sp( | |
| m_process->GetLoadedDynamicLibrariesInfos( | |
| eBinaryInformationLevelAddrOnly)); | |
| ImageInfo::collection image_infos; | |
| if (all_image_info_json_sp.get() && | |
| all_image_info_json_sp->GetAsDictionary() && | |
| all_image_info_json_sp->GetAsDictionary()->HasKey("images") && | |
| all_image_info_json_sp->GetAsDictionary() | |
| ->GetValueForKey("images") | |
| ->GetAsArray()) { | |
| // Older debugserver (pre-2024-ish) will not recognize the | |
| // eBinaryInformationLevelAddrOnly enum above, and | |
| // will return the full binary information including mach | |
| // header and segments/load commands. The response includes | |
| // the full information on all binaries. | |
| StructuredData::Array *images = all_image_info_json_sp->GetAsDictionary() | |
| ->GetValueForKey("images") | |
| ->GetAsArray(); | |
| if (images->GetSize() > 0 && images->GetItemAtIndex(0)->GetAsDictionary() && | |
| images->GetItemAtIndex(0)->GetAsDictionary()->HasKey("mach_header")) { | |
| if (JSONImageInformationIntoImageInfo(all_image_info_json_sp, | |
| image_infos)) { | |
| LLDB_LOGF(log, "Initial module fetch: Adding %" PRIu64 " modules.\n", | |
| (uint64_t)image_infos.size()); | |
| auto new_images = PreloadModulesFromImageInfos(image_infos); | |
| UpdateSpecialBinariesFromPreloadedModules(new_images); | |
| AddModulesUsingPreloadedModules(new_images); | |
| } | |
| } else { | |
| // This is a newer debugserver which only replied with | |
| // `load_address` for all binaries loaded in the process. | |
| // We can request detailed information in smaller chunks, | |
| // instead of one gigantic packet. | |
| size_t image_count = images->GetSize(); | |
| std::vector<addr_t> load_addresses; | |
| for (size_t i = 0; i < image_count; i++) { | |
| StructuredData::Dictionary *image = | |
| images->GetItemAtIndex(i)->GetAsDictionary(); | |
| if (image && image->HasKey("load_address")) { | |
| addr_t val = image->GetValueForKey("load_address") | |
| ->GetUnsignedIntegerValue(LLDB_INVALID_ADDRESS); | |
| if (val != LLDB_INVALID_ADDRESS) | |
| load_addresses.push_back(val); | |
| } | |
| } | |
| AddBinaries(load_addresses, /*expedited_binary_infos=*/{}); | |
| } | |
| } | |
| m_dyld_image_infos_stop_id = m_process->GetStopID(); | |
| m_maybe_image_infos_address = m_process->GetImageInfoAddress(); | |
| } | |
| bool DynamicLoaderMacOS::NeedToDoInitialImageFetch() { return true; } | |
| // Static callback function that gets called when our DYLD notification | |
| // breakpoint gets hit. We update all of our image infos and then let our super | |
| // class DynamicLoader class decide if we should stop or not (based on global | |
| // preference). | |
| bool DynamicLoaderMacOS::NotifyBreakpointHit(void *baton, | |
| StoppointCallbackContext *context, | |
| lldb::user_id_t break_id, | |
| lldb::user_id_t break_loc_id) { | |
| // | |
| // Our breakpoint on | |
| // | |
| // void lldb_image_notifier(enum dyld_image_mode mode, uint32_t infoCount, | |
| // const dyld_image_info info[]) | |
| // | |
| // has been hit. We need to read the arguments. | |
| DynamicLoaderMacOS *dyld_instance = (DynamicLoaderMacOS *)baton; | |
| ExecutionContext exe_ctx(context->exe_ctx_ref); | |
| Process *process = exe_ctx.GetProcessPtr(); | |
| // This is a sanity check just in case this dyld_instance is an old dyld | |
| // plugin's breakpoint still lying around. | |
| if (process != dyld_instance->m_process) | |
| return false; | |
| if (dyld_instance->m_image_infos_stop_id != UINT32_MAX && | |
| process->GetStopID() < dyld_instance->m_image_infos_stop_id) { | |
| return false; | |
| } | |
| const lldb::ABISP &abi = process->GetABI(); | |
| if (abi) { | |
| // Build up the value array to store the three arguments given above, then | |
| // get the values from the ABI: | |
| TypeSystemClangSP scratch_ts_sp = | |
| ScratchTypeSystemClang::GetForTarget(process->GetTarget()); | |
| if (!scratch_ts_sp) | |
| return false; | |
| ValueList argument_values; | |
| Value mode_value; // enum dyld_notify_mode { dyld_notify_adding=0, | |
| // dyld_notify_removing=1, dyld_notify_remove_all=2, | |
| // dyld_notify_dyld_moved=3 }; | |
| Value count_value; // uint32_t | |
| Value headers_value; // struct dyld_image_info machHeaders[] | |
| CompilerType clang_void_ptr_type = | |
| scratch_ts_sp->GetBasicType(eBasicTypeVoid).GetPointerType(); | |
| CompilerType clang_uint32_type = | |
| scratch_ts_sp->GetBuiltinTypeForEncodingAndBitSize(lldb::eEncodingUint, | |
| 32); | |
| CompilerType clang_uint64_type = | |
| scratch_ts_sp->GetBuiltinTypeForEncodingAndBitSize(lldb::eEncodingUint, | |
| 32); | |
| mode_value.SetValueType(Value::ValueType::Scalar); | |
| mode_value.SetCompilerType(clang_uint32_type); | |
| count_value.SetValueType(Value::ValueType::Scalar); | |
| count_value.SetCompilerType(clang_uint32_type); | |
| headers_value.SetValueType(Value::ValueType::Scalar); | |
| headers_value.SetCompilerType(clang_void_ptr_type); | |
| argument_values.PushValue(mode_value); | |
| argument_values.PushValue(count_value); | |
| argument_values.PushValue(headers_value); | |
| Thread &thread = exe_ctx.GetThreadRef(); | |
| if (abi->GetArgumentValues(thread, argument_values)) { | |
| uint32_t dyld_mode = | |
| argument_values.GetValueAtIndex(0)->GetScalar().UInt(-1); | |
| if (dyld_mode != static_cast<uint32_t>(-1)) { | |
| // Okay the mode was right, now get the number of elements, and the | |
| // array of new elements... | |
| uint32_t image_infos_count = | |
| argument_values.GetValueAtIndex(1)->GetScalar().UInt(-1); | |
| if (image_infos_count != static_cast<uint32_t>(-1)) { | |
| addr_t header_array = | |
| argument_values.GetValueAtIndex(2)->GetScalar().ULongLong(-1); | |
| if (header_array != static_cast<uint64_t>(-1)) { | |
| std::vector<addr_t> image_load_addresses; | |
| // header_array points to an array of image_infos_count elements, | |
| // each is | |
| // struct dyld_image_info { | |
| // const struct mach_header* imageLoadAddress; | |
| // const char* imageFilePath; | |
| // uintptr_t imageFileModDate; | |
| // }; | |
| // | |
| // and we only need the imageLoadAddress fields. | |
| // The remote stub may have provided the addresses in the | |
| // stop packet already. | |
| image_load_addresses = thread.FetchNewlyAddedBinaries(); | |
| // Or, read them from memory. | |
| if (image_load_addresses.size() != image_infos_count) { | |
| image_load_addresses.clear(); | |
| ArchSpec target_arch = process->GetTarget().GetArchitecture(); | |
| const int addrsize = target_arch.GetAddressByteSize(); | |
| // Read the entire block of memory that we'll need to | |
| // iterate over in one large read, to minimize packets sent. | |
| WritableDataBufferSP buffer_sp = std::make_shared<DataBufferHeap>( | |
| addrsize * 3 * image_infos_count, 0); | |
| Status read_error; | |
| if (process->ReadMemory(header_array, buffer_sp->GetBytes(), | |
| buffer_sp->GetByteSize(), | |
| read_error) == buffer_sp->GetByteSize() && | |
| read_error.Success()) { | |
| DataExtractor added_binaries( | |
| buffer_sp, target_arch.GetByteOrder(), addrsize); | |
| offset_t offset = 0; | |
| for (uint64_t i = 0; i < image_infos_count; i++) { | |
| addr_t addr = added_binaries.GetAddress(&offset); | |
| image_load_addresses.push_back(addr); | |
| offset += 2 * addrsize; | |
| } | |
| } | |
| if (!read_error.Success()) | |
| Debugger::ReportWarning( | |
| "DynamicLoaderMacOS::NotifyBreakpointHit unable " | |
| "to read binary mach-o load address at 0x%" PRIx64, | |
| header_array); | |
| } | |
| if (dyld_mode == 0) { | |
| // dyld_notify_adding | |
| if (process->GetTarget().GetImages().GetSize() == 0) { | |
| // When all images have been removed, we're doing the | |
| // dyld handover from a launch-dyld to a shared-cache-dyld, | |
| // and we've just hit our one-shot address breakpoint in | |
| // the sc-dyld. Note that the image addresses passed to | |
| // this function are inferior sizeof(void*) not uint64_t's | |
| // like our normal notification, so don't even look at | |
| // image_load_addresses. | |
| dyld_instance->ClearDYLDHandoverBreakpoint(); | |
| dyld_instance->DoInitialImageFetch(); | |
| dyld_instance->SetNotificationBreakpoint(); | |
| } else { | |
| dyld_instance->AddBinaries(image_load_addresses, | |
| thread.FetchDetailedBinariesInfo()); | |
| } | |
| } else if (dyld_mode == 1) { | |
| // dyld_notify_removing | |
| dyld_instance->UnloadImages(image_load_addresses); | |
| } else if (dyld_mode == 2) { | |
| // dyld_notify_remove_all | |
| dyld_instance->UnloadAllImages(); | |
| } else if (dyld_mode == 3 && image_infos_count == 1) { | |
| // dyld_image_dyld_moved | |
| dyld_instance->ClearNotificationBreakpoint(); | |
| dyld_instance->UnloadAllImages(); | |
| dyld_instance->ClearDYLDModule(); | |
| process->GetTarget().GetImages().Clear(); | |
| process->GetTarget().ClearSectionLoadList(); | |
| addr_t all_image_infos = process->GetImageInfoAddress(); | |
| int addr_size = | |
| process->GetTarget().GetArchitecture().GetAddressByteSize(); | |
| addr_t notification_location = all_image_infos + 4 + // version | |
| 4 + // infoArrayCount | |
| addr_size; // infoArray | |
| llvm::Expected<lldb::addr_t> notification_addr = | |
| process->ReadPointerFromMemory(notification_location); | |
| if (!notification_addr) { | |
| llvm::consumeError(notification_addr.takeError()); | |
| Debugger::ReportWarning( | |
| "DynamicLoaderMacOS::NotifyBreakpointHit unable " | |
| "to read address of dyld-handover notification function at " | |
| "0x%" PRIx64, | |
| notification_location); | |
| } else { | |
| dyld_instance->SetDYLDHandoverBreakpoint( | |
| process->FixCodeAddress(*notification_addr)); | |
| } | |
| } | |
| } | |
| } | |
| } | |
| } | |
| } else { | |
| Target &target = process->GetTarget(); | |
| Debugger::ReportWarning( | |
| "no ABI plugin located for triple " + | |
| target.GetArchitecture().GetTriple().getTriple() + | |
| ": shared libraries will not be registered", | |
| target.GetDebugger().GetID()); | |
| } | |
| // Return true to stop the target, false to just let the target run | |
| return dyld_instance->GetStopWhenImagesChange(); | |
| } | |
| static size_t LibraryInfosCount(StructuredData::ObjectSP binaries_info_sp) { | |
| if (!binaries_info_sp) | |
| return 0; | |
| if (StructuredData::Dictionary *dict = binaries_info_sp->GetAsDictionary()) { | |
| if (!dict->HasKey("images")) | |
| return 0; | |
| if (StructuredData::Array *images = | |
| dict->GetValueForKey("images")->GetAsArray()) | |
| return images->GetSize(); | |
| } | |
| return 0; | |
| } | |
| void DynamicLoaderMacOS::AddBinaries( | |
| const std::vector<lldb::addr_t> &load_addresses, | |
| StructuredData::ObjectSP expedited_binary_infos) { | |
| Log *log = GetLog(LLDBLog::DynamicLoader); | |
| ImageInfo::collection image_infos; | |
| if (load_addresses.empty()) | |
| return; | |
| // If the expedited detailed binaries information covers | |
| // all of the newly added binaries, use that info and | |
| // return. | |
| if (LibraryInfosCount(expedited_binary_infos) == load_addresses.size() && | |
| JSONImageInformationIntoImageInfo(expedited_binary_infos, image_infos)) { | |
| auto new_images = PreloadModulesFromImageInfos(image_infos); | |
| UpdateSpecialBinariesFromPreloadedModules(new_images); | |
| AddModulesUsingPreloadedModules(new_images); | |
| m_dyld_image_infos_stop_id = m_process->GetStopID(); | |
| return; | |
| } | |
| // For now, hardcode a limit of fetching 600 binaries at once. | |
| // Fetching the full binary information for a large number of | |
| // binaries can cause debugserver to use too much memory on | |
| // memory-limited environments, and get killed. | |
| const size_t image_fetch_max = 600; | |
| size_t fetched = 0; | |
| size_t total_image_size = load_addresses.size(); | |
| while (fetched < total_image_size) { | |
| size_t this_fetch_amt = | |
| std::min(image_fetch_max, total_image_size - fetched); | |
| std::vector<addr_t> fetch_binaries(load_addresses.begin() + fetched, | |
| load_addresses.begin() + fetched + | |
| this_fetch_amt); | |
| LLDB_LOGF(log, "Adding %" PRId64 " modules.", | |
| (uint64_t)fetch_binaries.size()); | |
| image_infos.clear(); | |
| StructuredData::ObjectSP binaries_info_sp = | |
| m_process->GetLoadedDynamicLibrariesInfos(eBinaryInformationLevelFull, | |
| fetch_binaries); | |
| if (LibraryInfosCount(binaries_info_sp) == fetch_binaries.size()) { | |
| if (JSONImageInformationIntoImageInfo(binaries_info_sp, image_infos)) { | |
| auto new_images = PreloadModulesFromImageInfos(image_infos); | |
| UpdateSpecialBinariesFromPreloadedModules(new_images); | |
| AddModulesUsingPreloadedModules(new_images); | |
| } | |
| } | |
| fetched += this_fetch_amt; | |
| } | |
| m_dyld_image_infos_stop_id = m_process->GetStopID(); | |
| } | |
| // Dump the _dyld_all_image_infos members and all current image infos that we | |
| // have parsed to the file handle provided. | |
| void DynamicLoaderMacOS::PutToLog(Log *log) const { | |
| if (log == nullptr) | |
| return; | |
| } | |
| // Look in dyld's dyld_all_image_infos structure for the address | |
| // of the notification function. | |
| // We can find the address of dyld_all_image_infos by a system | |
| // call, even if we don't have a dyld binary registered in lldb's | |
| // image list. | |
| // At process launch time - before dyld has executed any instructions - | |
| // the address of the notification function is not a resolved vm address | |
| // yet. dyld_all_image_infos also has a field with its own address | |
| // in it, and this will also be unresolved when we're at this state. | |
| // So we can compare the address of the object with this field and if | |
| // they differ, dyld hasn't started executing yet and we can't get the | |
| // notification address this way. | |
| addr_t DynamicLoaderMacOS::GetNotificationFuncAddrFromImageInfos() { | |
| addr_t notification_addr = LLDB_INVALID_ADDRESS; | |
| if (!m_process) | |
| return notification_addr; | |
| addr_t all_image_infos_addr = m_process->GetImageInfoAddress(); | |
| if (all_image_infos_addr == LLDB_INVALID_ADDRESS) | |
| return notification_addr; | |
| const uint32_t addr_size = | |
| m_process->GetTarget().GetArchitecture().GetAddressByteSize(); | |
| offset_t registered_infos_addr_offset = | |
| sizeof(uint32_t) + // version | |
| sizeof(uint32_t) + // infoArrayCount | |
| addr_size + // infoArray | |
| addr_size + // notification | |
| addr_size + // processDetachedFromSharedRegion + | |
| // libSystemInitialized + pad | |
| addr_size + // dyldImageLoadAddress | |
| addr_size + // jitInfo | |
| addr_size + // dyldVersion | |
| addr_size + // errorMessage | |
| addr_size + // terminationFlags | |
| addr_size + // coreSymbolicationShmPage | |
| addr_size + // systemOrderFlag | |
| addr_size + // uuidArrayCount | |
| addr_size; // uuidArray | |
| // dyldAllImageInfosAddress | |
| // If the dyldAllImageInfosAddress does not match | |
| // the actual address of this struct, dyld has not started | |
| // executing yet. The 'notification' field can't be used by | |
| // lldb until it's resolved to an actual address. | |
| llvm::Expected<lldb::addr_t> registered_infos_addr = | |
| m_process->ReadPointerFromMemory(all_image_infos_addr + | |
| registered_infos_addr_offset); | |
| if (!registered_infos_addr) { | |
| llvm::consumeError(registered_infos_addr.takeError()); | |
| return notification_addr; | |
| } | |
| if (*registered_infos_addr != all_image_infos_addr) | |
| return notification_addr; | |
| offset_t notification_fptr_offset = sizeof(uint32_t) + // version | |
| sizeof(uint32_t) + // infoArrayCount | |
| addr_size; // infoArray | |
| llvm::Expected<lldb::addr_t> notification_fptr = | |
| m_process->ReadPointerFromMemory(all_image_infos_addr + | |
| notification_fptr_offset); | |
| if (notification_fptr) | |
| notification_addr = m_process->FixCodeAddress(*notification_fptr); | |
| else | |
| llvm::consumeError(notification_fptr.takeError()); | |
| return notification_addr; | |
| } | |
| // We want to put a breakpoint on dyld's lldb_image_notifier() | |
| // but we may have attached to the process during the | |
| // transition from on-disk-dyld to shared-cache-dyld, so there's | |
| // officially no dyld binary loaded in the process (libdyld will | |
| // report none when asked), but the kernel can find the dyld_all_image_infos | |
| // struct and the function pointer for lldb_image_notifier is in | |
| // that struct. | |
| bool DynamicLoaderMacOS::SetNotificationBreakpoint() { | |
| // First try to find the notification breakpoint function by name | |
| if (m_break_id == LLDB_INVALID_BREAK_ID) { | |
| ModuleSP dyld_sp(GetDYLDModule()); | |
| if (dyld_sp) { | |
| bool internal = true; | |
| bool hardware = false; | |
| LazyBool skip_prologue = eLazyBoolNo; | |
| FileSpecList *source_files = nullptr; | |
| FileSpecList dyld_filelist; | |
| dyld_filelist.Append(dyld_sp->GetFileSpec()); | |
| Breakpoint *breakpoint = | |
| m_process->GetTarget() | |
| .CreateBreakpoint(&dyld_filelist, source_files, | |
| "lldb_image_notifier", eFunctionNameTypeFull, | |
| eLanguageTypeUnknown, 0, false, skip_prologue, | |
| internal, hardware) | |
| .get(); | |
| breakpoint->SetCallback(DynamicLoaderMacOS::NotifyBreakpointHit, this, | |
| true); | |
| breakpoint->SetBreakpointKind("shared-library-event"); | |
| if (breakpoint->HasResolvedLocations()) | |
| m_break_id = breakpoint->GetID(); | |
| else | |
| m_process->GetTarget().RemoveBreakpointByID(breakpoint->GetID()); | |
| if (m_break_id == LLDB_INVALID_BREAK_ID) { | |
| Breakpoint *breakpoint = | |
| m_process->GetTarget() | |
| .CreateBreakpoint(&dyld_filelist, source_files, | |
| "gdb_image_notifier", eFunctionNameTypeFull, | |
| eLanguageTypeUnknown, 0, | |
| /*offset_is_insn_count = */ false, | |
| skip_prologue, internal, hardware) | |
| .get(); | |
| breakpoint->SetCallback(DynamicLoaderMacOS::NotifyBreakpointHit, this, | |
| true); | |
| breakpoint->SetBreakpointKind("shared-library-event"); | |
| if (breakpoint->HasResolvedLocations()) | |
| m_break_id = breakpoint->GetID(); | |
| else | |
| m_process->GetTarget().RemoveBreakpointByID(breakpoint->GetID()); | |
| } | |
| } | |
| } | |
| // Failing that, find dyld_all_image_infos struct in memory, | |
| // read the notification function pointer at the offset. | |
| if (m_break_id == LLDB_INVALID_BREAK_ID) { | |
| addr_t notification_addr = GetNotificationFuncAddrFromImageInfos(); | |
| if (notification_addr != LLDB_INVALID_ADDRESS) { | |
| Address so_addr; | |
| // We may not have a dyld binary mapped to this address yet; | |
| // don't try to express the Address object as section+offset, | |
| // only as a raw load address. | |
| so_addr.SetRawAddress(notification_addr); | |
| Breakpoint *dyld_break = | |
| m_process->GetTarget().CreateBreakpoint(so_addr, true, false).get(); | |
| dyld_break->SetCallback(DynamicLoaderMacOS::NotifyBreakpointHit, this, | |
| true); | |
| dyld_break->SetBreakpointKind("shared-library-event"); | |
| if (dyld_break->HasResolvedLocations()) | |
| m_break_id = dyld_break->GetID(); | |
| else | |
| m_process->GetTarget().RemoveBreakpointByID(dyld_break->GetID()); | |
| } | |
| } | |
| return m_break_id != LLDB_INVALID_BREAK_ID; | |
| } | |
| bool DynamicLoaderMacOS::SetDYLDHandoverBreakpoint( | |
| addr_t notification_address) { | |
| if (m_dyld_handover_break_id == LLDB_INVALID_BREAK_ID) { | |
| BreakpointSP dyld_handover_bp = m_process->GetTarget().CreateBreakpoint( | |
| notification_address, true, false); | |
| dyld_handover_bp->SetCallback(DynamicLoaderMacOS::NotifyBreakpointHit, this, | |
| true); | |
| dyld_handover_bp->SetOneShot(true); | |
| m_dyld_handover_break_id = dyld_handover_bp->GetID(); | |
| return true; | |
| } | |
| return false; | |
| } | |
| void DynamicLoaderMacOS::ClearDYLDHandoverBreakpoint() { | |
| if (LLDB_BREAK_ID_IS_VALID(m_dyld_handover_break_id)) | |
| m_process->GetTarget().RemoveBreakpointByID(m_dyld_handover_break_id); | |
| m_dyld_handover_break_id = LLDB_INVALID_BREAK_ID; | |
| } | |
| addr_t | |
| DynamicLoaderMacOS::GetDyldLockVariableAddressFromModule(Module *module) { | |
| SymbolContext sc; | |
| Target &target = m_process->GetTarget(); | |
| if (Symtab *symtab = module->GetSymtab()) { | |
| std::vector<uint32_t> match_indexes; | |
| ConstString g_symbol_name("_dyld_global_lock_held"); | |
| uint32_t num_matches = 0; | |
| num_matches = | |
| symtab->AppendSymbolIndexesWithName(g_symbol_name, match_indexes); | |
| if (num_matches == 1) { | |
| const Symbol *symbol = symtab->SymbolAtIndex(match_indexes[0]); | |
| if (symbol && | |
| (symbol->ValueIsAddress() || symbol->GetAddressRef().IsValid())) { | |
| return symbol->GetAddressRef().GetOpcodeLoadAddress(&target); | |
| } | |
| } | |
| } | |
| return LLDB_INVALID_ADDRESS; | |
| } | |
| // Look for this symbol: | |
| // | |
| // int __attribute__((visibility("hidden"))) _dyld_global_lock_held = | |
| // 0; | |
| // | |
| // in libdyld.dylib. | |
| Status DynamicLoaderMacOS::CanLoadImage() { | |
| Status error; | |
| addr_t symbol_address = LLDB_INVALID_ADDRESS; | |
| ConstString g_libdyld_name("libdyld.dylib"); | |
| Target &target = m_process->GetTarget(); | |
| const ModuleList &target_modules = target.GetImages(); | |
| std::lock_guard<std::recursive_mutex> guard(target_modules.GetMutex()); | |
| // Find any modules named "libdyld.dylib" and look for the symbol there first | |
| for (ModuleSP module_sp : target.GetImages().ModulesNoLocking()) { | |
| if (module_sp) { | |
| if (module_sp->GetFileSpec().GetFilename() == g_libdyld_name) { | |
| symbol_address = GetDyldLockVariableAddressFromModule(module_sp.get()); | |
| if (symbol_address != LLDB_INVALID_ADDRESS) | |
| break; | |
| } | |
| } | |
| } | |
| // Search through all modules looking for the symbol in them | |
| if (symbol_address == LLDB_INVALID_ADDRESS) { | |
| for (ModuleSP module_sp : target.GetImages().Modules()) { | |
| if (module_sp) { | |
| addr_t symbol_address = | |
| GetDyldLockVariableAddressFromModule(module_sp.get()); | |
| if (symbol_address != LLDB_INVALID_ADDRESS) | |
| break; | |
| } | |
| } | |
| } | |
| // Default assumption is that it is OK to load images. Only say that we | |
| // cannot load images if we find the symbol in libdyld and it indicates that | |
| // we cannot. | |
| if (symbol_address != LLDB_INVALID_ADDRESS) { | |
| { | |
| int lock_held = | |
| m_process->ReadUnsignedIntegerFromMemory(symbol_address, 4, 0, error); | |
| if (lock_held != 0) { | |
| error = | |
| Status::FromErrorString("dyld lock held - unsafe to load images."); | |
| } | |
| } | |
| } else { | |
| // If we were unable to find _dyld_global_lock_held in any modules, or it | |
| // is not loaded into memory yet, we may be at process startup (sitting at | |
| // _dyld_start) - so we should not allow dlopen calls. But if we found more | |
| // than one module then we are clearly past _dyld_start so in that case | |
| // we'll default to "it's safe". | |
| if (target.GetImages().GetSize() <= 1) | |
| error = Status::FromErrorString("could not find the dyld library or " | |
| "the dyld lock symbol"); | |
| } | |
| return error; | |
| } | |
| bool DynamicLoaderMacOS::GetSharedCacheInformation( | |
| lldb::addr_t &base_address, UUID &uuid, LazyBool &using_shared_cache, | |
| LazyBool &private_shared_cache, FileSpec &shared_cache_path, | |
| std::optional<uint64_t> &size) { | |
| base_address = LLDB_INVALID_ADDRESS; | |
| uuid.Clear(); | |
| using_shared_cache = eLazyBoolCalculate; | |
| private_shared_cache = eLazyBoolCalculate; | |
| size.reset(); | |
| if (m_process) { | |
| StructuredData::ObjectSP info = m_process->GetSharedCacheInfo(); | |
| StructuredData::Dictionary *info_dict = nullptr; | |
| if (info.get() && info->GetAsDictionary()) { | |
| info_dict = info->GetAsDictionary(); | |
| } | |
| // { "shared_cache_base_address":6580879360, | |
| // "shared_cache_uuid":"71E62C65-D8D9-32D0-9A0B-7F5154C8049F", | |
| // "no_shared_cache":false, | |
| // "shared_cache_private_cache":false, | |
| // "shared_cache_path":"/S/V/P/C/OS/Sm/L/dyld/dyld_shared_cache_arm64e", | |
| // "shared_cache_size":6012010496 | |
| // } | |
| if (info_dict && info_dict->HasKey("shared_cache_uuid") && | |
| info_dict->HasKey("no_shared_cache") && | |
| info_dict->HasKey("shared_cache_private_cache") && | |
| info_dict->HasKey("shared_cache_base_address")) { | |
| base_address = info_dict->GetValueForKey("shared_cache_base_address") | |
| ->GetUnsignedIntegerValue(LLDB_INVALID_ADDRESS); | |
| std::string uuid_str = std::string( | |
| info_dict->GetValueForKey("shared_cache_uuid")->GetStringValue()); | |
| if (!uuid_str.empty()) | |
| uuid.SetFromStringRef(uuid_str); | |
| if (!info_dict->GetValueForKey("no_shared_cache")->GetBooleanValue()) | |
| using_shared_cache = eLazyBoolYes; | |
| else | |
| using_shared_cache = eLazyBoolNo; | |
| if (info_dict->GetValueForKey("shared_cache_private_cache") | |
| ->GetBooleanValue()) | |
| private_shared_cache = eLazyBoolYes; | |
| else | |
| private_shared_cache = eLazyBoolNo; | |
| if (info_dict->HasKey("shared_cache_path")) { | |
| llvm::StringRef filepath = | |
| info_dict->GetValueForKey("shared_cache_path")->GetStringValue(); | |
| shared_cache_path.SetPath(filepath); | |
| } | |
| if (info_dict->HasKey("shared_cache_size")) { | |
| uint64_t val = info_dict->GetValueForKey("shared_cache_size") | |
| ->GetUnsignedIntegerValue(LLDB_INVALID_ADDRESS); | |
| if (val != LLDB_INVALID_ADDRESS) | |
| size = val; | |
| } | |
| return true; | |
| } | |
| } | |
| return false; | |
| } | |
| void DynamicLoaderMacOS::Initialize() { | |
| PluginManager::RegisterPlugin(GetPluginNameStatic(), | |
| GetPluginDescriptionStatic(), CreateInstance); | |
| } | |
| void DynamicLoaderMacOS::Terminate() { | |
| PluginManager::UnregisterPlugin(CreateInstance); | |
| } | |
| llvm::StringRef DynamicLoaderMacOS::GetPluginDescriptionStatic() { | |
| return "Dynamic loader plug-in that watches for shared library loads/unloads " | |
| "in MacOSX user processes."; | |
| } |