1 //===-- DynamicLoader.cpp -------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "lldb/Target/DynamicLoader.h" 10 11 #include "lldb/Core/Debugger.h" 12 #include "lldb/Core/Module.h" 13 #include "lldb/Core/ModuleList.h" 14 #include "lldb/Core/ModuleSpec.h" 15 #include "lldb/Core/PluginManager.h" 16 #include "lldb/Core/Progress.h" 17 #include "lldb/Core/Section.h" 18 #include "lldb/Symbol/ObjectFile.h" 19 #include "lldb/Target/MemoryRegionInfo.h" 20 #include "lldb/Target/Platform.h" 21 #include "lldb/Target/Process.h" 22 #include "lldb/Target/Target.h" 23 #include "lldb/Utility/ConstString.h" 24 #include "lldb/Utility/LLDBLog.h" 25 #include "lldb/Utility/Log.h" 26 #include "lldb/lldb-private-interfaces.h" 27 28 #include "llvm/ADT/StringRef.h" 29 30 #include <memory> 31 32 #include <cassert> 33 34 using namespace lldb; 35 using namespace lldb_private; 36 37 DynamicLoader *DynamicLoader::FindPlugin(Process *process, 38 llvm::StringRef plugin_name) { 39 DynamicLoaderCreateInstance create_callback = nullptr; 40 if (!plugin_name.empty()) { 41 create_callback = 42 PluginManager::GetDynamicLoaderCreateCallbackForPluginName(plugin_name); 43 if (create_callback) { 44 std::unique_ptr<DynamicLoader> instance_up( 45 create_callback(process, true)); 46 if (instance_up) 47 return instance_up.release(); 48 } 49 } else { 50 for (uint32_t idx = 0; 51 (create_callback = 52 PluginManager::GetDynamicLoaderCreateCallbackAtIndex(idx)) != 53 nullptr; 54 ++idx) { 55 std::unique_ptr<DynamicLoader> instance_up( 56 create_callback(process, false)); 57 if (instance_up) 58 return instance_up.release(); 59 } 60 } 61 return nullptr; 62 } 63 64 DynamicLoader::DynamicLoader(Process *process) : m_process(process) {} 65 66 // Accessors to the global setting as to whether to stop at image (shared 67 // library) loading/unloading. 68 69 bool DynamicLoader::GetStopWhenImagesChange() const { 70 return m_process->GetStopOnSharedLibraryEvents(); 71 } 72 73 void DynamicLoader::SetStopWhenImagesChange(bool stop) { 74 m_process->SetStopOnSharedLibraryEvents(stop); 75 } 76 77 ModuleSP DynamicLoader::GetTargetExecutable() { 78 Target &target = m_process->GetTarget(); 79 ModuleSP executable = target.GetExecutableModule(); 80 81 if (executable) { 82 if (FileSystem::Instance().Exists(executable->GetFileSpec())) { 83 ModuleSpec module_spec(executable->GetFileSpec(), 84 executable->GetArchitecture()); 85 auto module_sp = std::make_shared<Module>(module_spec); 86 87 // Check if the executable has changed and set it to the target 88 // executable if they differ. 89 if (module_sp && module_sp->GetUUID().IsValid() && 90 executable->GetUUID().IsValid()) { 91 if (module_sp->GetUUID() != executable->GetUUID()) 92 executable.reset(); 93 } else if (executable->FileHasChanged()) { 94 executable.reset(); 95 } 96 97 if (!executable) { 98 executable = target.GetOrCreateModule(module_spec, true /* notify */); 99 if (executable.get() != target.GetExecutableModulePointer()) { 100 // Don't load dependent images since we are in dyld where we will 101 // know and find out about all images that are loaded 102 target.SetExecutableModule(executable, eLoadDependentsNo); 103 } 104 } 105 } 106 } 107 return executable; 108 } 109 110 void DynamicLoader::UpdateLoadedSections(ModuleSP module, addr_t link_map_addr, 111 addr_t base_addr, 112 bool base_addr_is_offset) { 113 UpdateLoadedSectionsCommon(module, base_addr, base_addr_is_offset); 114 } 115 116 void DynamicLoader::UpdateLoadedSectionsCommon(ModuleSP module, 117 addr_t base_addr, 118 bool base_addr_is_offset) { 119 bool changed; 120 module->SetLoadAddress(m_process->GetTarget(), base_addr, base_addr_is_offset, 121 changed); 122 } 123 124 void DynamicLoader::UnloadSections(const ModuleSP module) { 125 UnloadSectionsCommon(module); 126 } 127 128 void DynamicLoader::UnloadSectionsCommon(const ModuleSP module) { 129 Target &target = m_process->GetTarget(); 130 const SectionList *sections = GetSectionListFromModule(module); 131 132 assert(sections && "SectionList missing from unloaded module."); 133 134 const size_t num_sections = sections->GetSize(); 135 for (size_t i = 0; i < num_sections; ++i) { 136 SectionSP section_sp(sections->GetSectionAtIndex(i)); 137 target.SetSectionUnloaded(section_sp); 138 } 139 } 140 141 const SectionList * 142 DynamicLoader::GetSectionListFromModule(const ModuleSP module) const { 143 SectionList *sections = nullptr; 144 if (module) { 145 ObjectFile *obj_file = module->GetObjectFile(); 146 if (obj_file != nullptr) { 147 sections = obj_file->GetSectionList(); 148 } 149 } 150 return sections; 151 } 152 153 ModuleSP DynamicLoader::FindModuleViaTarget(const FileSpec &file) { 154 Target &target = m_process->GetTarget(); 155 ModuleSpec module_spec(file, target.GetArchitecture()); 156 157 if (ModuleSP module_sp = target.GetImages().FindFirstModule(module_spec)) 158 return module_sp; 159 160 if (ModuleSP module_sp = target.GetOrCreateModule(module_spec, false)) 161 return module_sp; 162 163 return nullptr; 164 } 165 166 ModuleSP DynamicLoader::LoadModuleAtAddress(const FileSpec &file, 167 addr_t link_map_addr, 168 addr_t base_addr, 169 bool base_addr_is_offset) { 170 if (ModuleSP module_sp = FindModuleViaTarget(file)) { 171 UpdateLoadedSections(module_sp, link_map_addr, base_addr, 172 base_addr_is_offset); 173 return module_sp; 174 } 175 176 return nullptr; 177 } 178 179 static ModuleSP ReadUnnamedMemoryModule(Process *process, addr_t addr, 180 llvm::StringRef name) { 181 char namebuf[80]; 182 if (name.empty()) { 183 snprintf(namebuf, sizeof(namebuf), "memory-image-0x%" PRIx64, addr); 184 name = namebuf; 185 } 186 return process->ReadModuleFromMemory(FileSpec(name), addr); 187 } 188 189 ModuleSP DynamicLoader::LoadBinaryWithUUIDAndAddress( 190 Process *process, llvm::StringRef name, UUID uuid, addr_t value, 191 bool value_is_offset, bool force_symbol_search, bool notify, 192 bool set_address_in_target, bool allow_memory_image_last_resort) { 193 ModuleSP memory_module_sp; 194 ModuleSP module_sp; 195 PlatformSP platform_sp = process->GetTarget().GetPlatform(); 196 Target &target = process->GetTarget(); 197 Status error; 198 199 StreamString prog_str; 200 if (!name.empty()) { 201 prog_str << name.str() << " "; 202 } 203 if (uuid.IsValid()) 204 prog_str << uuid.GetAsString(); 205 if (value_is_offset == 0 && value != LLDB_INVALID_ADDRESS) { 206 prog_str << "at 0x"; 207 prog_str.PutHex64(value); 208 } 209 210 if (!uuid.IsValid() && !value_is_offset) { 211 memory_module_sp = ReadUnnamedMemoryModule(process, value, name); 212 213 if (memory_module_sp) { 214 uuid = memory_module_sp->GetUUID(); 215 if (uuid.IsValid()) { 216 prog_str << " "; 217 prog_str << uuid.GetAsString(); 218 } 219 } 220 } 221 ModuleSpec module_spec; 222 module_spec.GetUUID() = uuid; 223 FileSpec name_filespec(name); 224 225 if (uuid.IsValid()) { 226 Progress progress("Locating binary", prog_str.GetString().str()); 227 228 // Has lldb already seen a module with this UUID? 229 // Or have external lookup enabled in DebugSymbols on macOS. 230 if (!module_sp) 231 error = ModuleList::GetSharedModule(module_spec, module_sp, nullptr, 232 nullptr, nullptr); 233 234 // Can lldb's symbol/executable location schemes 235 // find an executable and symbol file. 236 if (!module_sp) { 237 FileSpecList search_paths = Target::GetDefaultDebugFileSearchPaths(); 238 module_spec.GetSymbolFileSpec() = 239 PluginManager::LocateExecutableSymbolFile(module_spec, search_paths); 240 ModuleSpec objfile_module_spec = 241 PluginManager::LocateExecutableObjectFile(module_spec); 242 module_spec.GetFileSpec() = objfile_module_spec.GetFileSpec(); 243 if (FileSystem::Instance().Exists(module_spec.GetFileSpec()) && 244 FileSystem::Instance().Exists(module_spec.GetSymbolFileSpec())) { 245 module_sp = std::make_shared<Module>(module_spec); 246 } 247 } 248 249 // If we haven't found a binary, or we don't have a SymbolFile, see 250 // if there is an external search tool that can find it. 251 if (!module_sp || !module_sp->GetSymbolFileFileSpec()) { 252 PluginManager::DownloadObjectAndSymbolFile(module_spec, error, 253 force_symbol_search); 254 if (FileSystem::Instance().Exists(module_spec.GetFileSpec())) { 255 module_sp = std::make_shared<Module>(module_spec); 256 } else if (force_symbol_search && error.AsCString("") && 257 error.AsCString("")[0] != '\0') { 258 target.GetDebugger().GetErrorStream() << error.AsCString(); 259 } 260 } 261 262 // If we only found the executable, create a Module based on that. 263 if (!module_sp && FileSystem::Instance().Exists(module_spec.GetFileSpec())) 264 module_sp = std::make_shared<Module>(module_spec); 265 } 266 267 // If we couldn't find the binary anywhere else, as a last resort, 268 // read it out of memory. 269 if (allow_memory_image_last_resort && !module_sp.get() && 270 value != LLDB_INVALID_ADDRESS && !value_is_offset) { 271 if (!memory_module_sp) 272 memory_module_sp = ReadUnnamedMemoryModule(process, value, name); 273 if (memory_module_sp) 274 module_sp = memory_module_sp; 275 } 276 277 Log *log = GetLog(LLDBLog::DynamicLoader); 278 if (module_sp.get()) { 279 // Ensure the Target has an architecture set in case 280 // we need it while processing this binary/eh_frame/debug info. 281 if (!target.GetArchitecture().IsValid()) 282 target.SetArchitecture(module_sp->GetArchitecture()); 283 target.GetImages().AppendIfNeeded(module_sp, false); 284 285 bool changed = false; 286 if (set_address_in_target) { 287 if (module_sp->GetObjectFile()) { 288 if (value != LLDB_INVALID_ADDRESS) { 289 LLDB_LOGF(log, 290 "DynamicLoader::LoadBinaryWithUUIDAndAddress Loading " 291 "binary %s UUID %s at %s 0x%" PRIx64, 292 name.str().c_str(), uuid.GetAsString().c_str(), 293 value_is_offset ? "offset" : "address", value); 294 module_sp->SetLoadAddress(target, value, value_is_offset, changed); 295 } else { 296 // No address/offset/slide, load the binary at file address, 297 // offset 0. 298 LLDB_LOGF(log, 299 "DynamicLoader::LoadBinaryWithUUIDAndAddress Loading " 300 "binary %s UUID %s at file address", 301 name.str().c_str(), uuid.GetAsString().c_str()); 302 module_sp->SetLoadAddress(target, 0, true /* value_is_slide */, 303 changed); 304 } 305 } else { 306 // In-memory image, load at its true address, offset 0. 307 LLDB_LOGF(log, 308 "DynamicLoader::LoadBinaryWithUUIDAndAddress Loading binary " 309 "%s UUID %s from memory at address 0x%" PRIx64, 310 name.str().c_str(), uuid.GetAsString().c_str(), value); 311 module_sp->SetLoadAddress(target, 0, true /* value_is_slide */, 312 changed); 313 } 314 } 315 316 if (notify) { 317 ModuleList added_module; 318 added_module.Append(module_sp, false); 319 target.ModulesDidLoad(added_module); 320 } 321 } else { 322 if (force_symbol_search) { 323 Stream &s = target.GetDebugger().GetErrorStream(); 324 s.Printf("Unable to find file"); 325 if (!name.empty()) 326 s.Printf(" %s", name.str().c_str()); 327 if (uuid.IsValid()) 328 s.Printf(" with UUID %s", uuid.GetAsString().c_str()); 329 if (value != LLDB_INVALID_ADDRESS) { 330 if (value_is_offset) 331 s.Printf(" with slide 0x%" PRIx64, value); 332 else 333 s.Printf(" at address 0x%" PRIx64, value); 334 } 335 s.Printf("\n"); 336 } 337 LLDB_LOGF(log, 338 "Unable to find binary %s with UUID %s and load it at " 339 "%s 0x%" PRIx64, 340 name.str().c_str(), uuid.GetAsString().c_str(), 341 value_is_offset ? "offset" : "address", value); 342 } 343 344 return module_sp; 345 } 346 347 int64_t DynamicLoader::ReadUnsignedIntWithSizeInBytes(addr_t addr, 348 int size_in_bytes) { 349 Status error; 350 uint64_t value = 351 m_process->ReadUnsignedIntegerFromMemory(addr, size_in_bytes, 0, error); 352 if (error.Fail()) 353 return -1; 354 else 355 return (int64_t)value; 356 } 357 358 addr_t DynamicLoader::ReadPointer(addr_t addr) { 359 Status error; 360 addr_t value = m_process->ReadPointerFromMemory(addr, error); 361 if (error.Fail()) 362 return LLDB_INVALID_ADDRESS; 363 else 364 return value; 365 } 366 367 void DynamicLoader::LoadOperatingSystemPlugin(bool flush) 368 { 369 if (m_process) 370 m_process->LoadOperatingSystemPlugin(flush); 371 } 372 373