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1//===-- DynamicLoaderPOSIXDYLD.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-exception6//7//===----------------------------------------------------------------------===//8 9// Main header include10#include "DynamicLoaderPOSIXDYLD.h"11 12#include "lldb/Breakpoint/BreakpointLocation.h"13#include "lldb/Core/Debugger.h"14#include "lldb/Core/Module.h"15#include "lldb/Core/ModuleSpec.h"16#include "lldb/Core/PluginManager.h"17#include "lldb/Core/Section.h"18#include "lldb/Symbol/Function.h"19#include "lldb/Symbol/ObjectFile.h"20#include "lldb/Target/MemoryRegionInfo.h"21#include "lldb/Target/Platform.h"22#include "lldb/Target/RegisterContext.h"23#include "lldb/Target/Target.h"24#include "lldb/Target/Thread.h"25#include "lldb/Target/ThreadPlanRunToAddress.h"26#include "lldb/Utility/LLDBLog.h"27#include "lldb/Utility/Log.h"28#include "lldb/Utility/ProcessInfo.h"29#include "llvm/Support/ThreadPool.h"30 31#include <memory>32#include <optional>33 34using namespace lldb;35using namespace lldb_private;36 37LLDB_PLUGIN_DEFINE_ADV(DynamicLoaderPOSIXDYLD, DynamicLoaderPosixDYLD)38 39void DynamicLoaderPOSIXDYLD::Initialize() {40  PluginManager::RegisterPlugin(GetPluginNameStatic(),41                                GetPluginDescriptionStatic(), CreateInstance);42}43 44void DynamicLoaderPOSIXDYLD::Terminate() {}45 46llvm::StringRef DynamicLoaderPOSIXDYLD::GetPluginDescriptionStatic() {47  return "Dynamic loader plug-in that watches for shared library "48         "loads/unloads in POSIX processes.";49}50 51DynamicLoader *DynamicLoaderPOSIXDYLD::CreateInstance(Process *process,52                                                      bool force) {53  bool create = force;54  if (!create) {55    const llvm::Triple &triple_ref =56        process->GetTarget().GetArchitecture().GetTriple();57    if (triple_ref.getOS() == llvm::Triple::FreeBSD ||58        triple_ref.getOS() == llvm::Triple::Linux ||59        triple_ref.getOS() == llvm::Triple::NetBSD ||60        triple_ref.getOS() == llvm::Triple::OpenBSD)61      create = true;62  }63 64  if (create)65    return new DynamicLoaderPOSIXDYLD(process);66  return nullptr;67}68 69DynamicLoaderPOSIXDYLD::DynamicLoaderPOSIXDYLD(Process *process)70    : DynamicLoader(process), m_rendezvous(process),71      m_load_offset(LLDB_INVALID_ADDRESS), m_entry_point(LLDB_INVALID_ADDRESS),72      m_auxv(), m_dyld_bid(LLDB_INVALID_BREAK_ID),73      m_vdso_base(LLDB_INVALID_ADDRESS),74      m_interpreter_base(LLDB_INVALID_ADDRESS), m_initial_modules_added(false) {75}76 77DynamicLoaderPOSIXDYLD::~DynamicLoaderPOSIXDYLD() {78  if (m_dyld_bid != LLDB_INVALID_BREAK_ID) {79    m_process->GetTarget().RemoveBreakpointByID(m_dyld_bid);80    m_dyld_bid = LLDB_INVALID_BREAK_ID;81  }82}83 84void DynamicLoaderPOSIXDYLD::DidAttach() {85  Log *log = GetLog(LLDBLog::DynamicLoader);86  LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s() pid %" PRIu64, __FUNCTION__,87            m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);88  m_auxv = std::make_unique<AuxVector>(m_process->GetAuxvData());89 90  LLDB_LOGF(91      log, "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64 " reloaded auxv data",92      __FUNCTION__, m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);93 94  ModuleSP executable_sp = GetTargetExecutable();95  ResolveExecutableModule(executable_sp);96  m_rendezvous.UpdateExecutablePath();97 98  // find the main process load offset99  addr_t load_offset = ComputeLoadOffset();100  LLDB_LOGF(log,101            "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64102            " executable '%s', load_offset 0x%" PRIx64,103            __FUNCTION__,104            m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID,105            executable_sp ? executable_sp->GetFileSpec().GetPath().c_str()106                          : "<null executable>",107            load_offset);108 109  EvalSpecialModulesStatus();110 111  // if we dont have a load address we cant re-base112  bool rebase_exec = load_offset != LLDB_INVALID_ADDRESS;113 114  // if the target executable should be re-based115  if (rebase_exec) {116    ModuleList module_list;117 118    module_list.Append(executable_sp);119    LLDB_LOGF(log,120              "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64121              " added executable '%s' to module load list",122              __FUNCTION__,123              m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID,124              executable_sp->GetFileSpec().GetPath().c_str());125 126    UpdateLoadedSections(executable_sp, LLDB_INVALID_ADDRESS, load_offset,127                         true);128 129    LoadAllCurrentModules();130 131    m_process->GetTarget().ModulesDidLoad(module_list);132    if (log) {133      LLDB_LOGF(log,134                "DynamicLoaderPOSIXDYLD::%s told the target about the "135                "modules that loaded:",136                __FUNCTION__);137      for (auto module_sp : module_list.Modules()) {138        LLDB_LOGF(log, "-- [module] %s (pid %" PRIu64 ")",139                  module_sp ? module_sp->GetFileSpec().GetPath().c_str()140                            : "<null>",141                  m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);142      }143    }144  }145 146  if (executable_sp.get()) {147    if (!SetRendezvousBreakpoint()) {148      // If we cannot establish rendezvous breakpoint right now we'll try again149      // at entry point.150      ProbeEntry();151    }152  }153}154 155void DynamicLoaderPOSIXDYLD::DidLaunch() {156  Log *log = GetLog(LLDBLog::DynamicLoader);157  LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s()", __FUNCTION__);158 159  ModuleSP executable;160  addr_t load_offset;161 162  m_auxv = std::make_unique<AuxVector>(m_process->GetAuxvData());163 164  executable = GetTargetExecutable();165  load_offset = ComputeLoadOffset();166  EvalSpecialModulesStatus();167 168  if (executable.get() && load_offset != LLDB_INVALID_ADDRESS) {169    ModuleList module_list;170    module_list.Append(executable);171    UpdateLoadedSections(executable, LLDB_INVALID_ADDRESS, load_offset, true);172 173    LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s about to call ProbeEntry()",174              __FUNCTION__);175 176    if (!SetRendezvousBreakpoint()) {177      // If we cannot establish rendezvous breakpoint right now we'll try again178      // at entry point.179      ProbeEntry();180    }181 182    LoadVDSO();183    m_process->GetTarget().ModulesDidLoad(module_list);184  }185}186 187Status DynamicLoaderPOSIXDYLD::CanLoadImage() { return Status(); }188 189void DynamicLoaderPOSIXDYLD::SetLoadedModule(const ModuleSP &module_sp,190                                             addr_t link_map_addr) {191  llvm::sys::ScopedWriter lock(m_loaded_modules_rw_mutex);192  m_loaded_modules[module_sp] = link_map_addr;193}194 195void DynamicLoaderPOSIXDYLD::UnloadModule(const ModuleSP &module_sp) {196  llvm::sys::ScopedWriter lock(m_loaded_modules_rw_mutex);197  m_loaded_modules.erase(module_sp);198}199 200std::optional<lldb::addr_t>201DynamicLoaderPOSIXDYLD::GetLoadedModuleLinkAddr(const ModuleSP &module_sp) {202  llvm::sys::ScopedReader lock(m_loaded_modules_rw_mutex);203  auto it = m_loaded_modules.find(module_sp);204  if (it != m_loaded_modules.end())205    return it->second;206  return std::nullopt;207}208 209void DynamicLoaderPOSIXDYLD::UpdateLoadedSections(ModuleSP module,210                                                  addr_t link_map_addr,211                                                  addr_t base_addr,212                                                  bool base_addr_is_offset) {213  SetLoadedModule(module, link_map_addr);214 215  UpdateLoadedSectionsCommon(module, base_addr, base_addr_is_offset);216}217 218void DynamicLoaderPOSIXDYLD::UnloadSections(const ModuleSP module) {219  UnloadModule(module);220 221  UnloadSectionsCommon(module);222}223 224void DynamicLoaderPOSIXDYLD::ProbeEntry() {225  Log *log = GetLog(LLDBLog::DynamicLoader);226 227  // If we have a core file, we don't need any breakpoints.228  if (IsCoreFile())229    return;230 231  const addr_t entry = GetEntryPoint();232  if (entry == LLDB_INVALID_ADDRESS) {233    LLDB_LOGF(234        log,235        "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64236        " GetEntryPoint() returned no address, not setting entry breakpoint",237        __FUNCTION__, m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);238    return;239  }240 241  LLDB_LOGF(log,242            "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64243            " GetEntryPoint() returned address 0x%" PRIx64244            ", setting entry breakpoint",245            __FUNCTION__,246            m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID, entry);247 248  if (m_process) {249    Breakpoint *const entry_break =250        m_process->GetTarget().CreateBreakpoint(entry, true, false).get();251    entry_break->SetCallback(EntryBreakpointHit, this, true);252    entry_break->SetBreakpointKind("shared-library-event");253 254    // Shoudn't hit this more than once.255    entry_break->SetOneShot(true);256  }257}258 259// The runtime linker has run and initialized the rendezvous structure once the260// process has hit its entry point.  When we hit the corresponding breakpoint261// we interrogate the rendezvous structure to get the load addresses of all262// dependent modules for the process.  Similarly, we can discover the runtime263// linker function and setup a breakpoint to notify us of any dynamically264// loaded modules (via dlopen).265bool DynamicLoaderPOSIXDYLD::EntryBreakpointHit(266    void *baton, StoppointCallbackContext *context, user_id_t break_id,267    user_id_t break_loc_id) {268  assert(baton && "null baton");269  if (!baton)270    return false;271 272  Log *log = GetLog(LLDBLog::DynamicLoader);273  DynamicLoaderPOSIXDYLD *const dyld_instance =274      static_cast<DynamicLoaderPOSIXDYLD *>(baton);275  LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s called for pid %" PRIu64,276            __FUNCTION__,277            dyld_instance->m_process ? dyld_instance->m_process->GetID()278                                     : LLDB_INVALID_PROCESS_ID);279 280  // Disable the breakpoint --- if a stop happens right after this, which we've281  // seen on occasion, we don't want the breakpoint stepping thread-plan logic282  // to show a breakpoint instruction at the disassembled entry point to the283  // program.  Disabling it prevents it.  (One-shot is not enough - one-shot284  // removal logic only happens after the breakpoint goes public, which wasn't285  // happening in our scenario).286  if (dyld_instance->m_process) {287    BreakpointSP breakpoint_sp =288        dyld_instance->m_process->GetTarget().GetBreakpointByID(break_id);289    if (breakpoint_sp) {290      LLDB_LOGF(log,291                "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64292                " disabling breakpoint id %" PRIu64,293                __FUNCTION__, dyld_instance->m_process->GetID(), break_id);294      breakpoint_sp->SetEnabled(false);295    } else {296      LLDB_LOGF(log,297                "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64298                " failed to find breakpoint for breakpoint id %" PRIu64,299                __FUNCTION__, dyld_instance->m_process->GetID(), break_id);300    }301  } else {302    LLDB_LOGF(log,303              "DynamicLoaderPOSIXDYLD::%s breakpoint id %" PRIu64304              " no Process instance!  Cannot disable breakpoint",305              __FUNCTION__, break_id);306  }307 308  dyld_instance->LoadAllCurrentModules();309  dyld_instance->SetRendezvousBreakpoint();310  return false; // Continue running.311}312 313bool DynamicLoaderPOSIXDYLD::SetRendezvousBreakpoint() {314  Log *log = GetLog(LLDBLog::DynamicLoader);315 316  // If we have a core file, we don't need any breakpoints.317  if (IsCoreFile())318    return false;319 320  if (m_dyld_bid != LLDB_INVALID_BREAK_ID) {321    LLDB_LOG(log,322             "Rendezvous breakpoint breakpoint id {0} for pid {1}"323             "is already set.",324             m_dyld_bid,325             m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);326    return true;327  }328 329  addr_t break_addr;330  Target &target = m_process->GetTarget();331  BreakpointSP dyld_break;332  if (m_rendezvous.IsValid() && m_rendezvous.GetBreakAddress() != 0) {333    break_addr = m_rendezvous.GetBreakAddress();334    LLDB_LOG(log, "Setting rendezvous break address for pid {0} at {1:x}",335             m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID,336             break_addr);337    dyld_break = target.CreateBreakpoint(break_addr, true, false);338  } else {339    LLDB_LOG(log, "Rendezvous structure is not set up yet. "340                  "Trying to locate rendezvous breakpoint in the interpreter "341                  "by symbol name.");342    // Function names from different dynamic loaders that are known to be343    // used as rendezvous between the loader and debuggers.344    static std::vector<std::string> DebugStateCandidates{345        "_dl_debug_state", "rtld_db_dlactivity", "__dl_rtld_db_dlactivity",346        "r_debug_state",   "_r_debug_state",     "_rtld_debug_state",347    };348 349    ModuleSP interpreter = LoadInterpreterModule();350    FileSpecList containingModules;351    if (interpreter)352      containingModules.Append(interpreter->GetFileSpec());353    else354      containingModules.Append(355          m_process->GetTarget().GetExecutableModulePointer()->GetFileSpec());356 357    dyld_break = target.CreateBreakpoint(358        &containingModules, /*containingSourceFiles=*/nullptr,359        DebugStateCandidates, eFunctionNameTypeFull, eLanguageTypeC,360        /*m_offset=*/0,361        /*skip_prologue=*/eLazyBoolNo,362        /*internal=*/true,363        /*request_hardware=*/false);364  }365 366  if (dyld_break->GetNumResolvedLocations() != 1) {367    LLDB_LOG(368        log,369        "Rendezvous breakpoint has abnormal number of"370        " resolved locations ({0}) in pid {1}. It's supposed to be exactly 1.",371        dyld_break->GetNumResolvedLocations(),372        m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);373 374    target.RemoveBreakpointByID(dyld_break->GetID());375    return false;376  }377 378  BreakpointLocationSP location = dyld_break->GetLocationAtIndex(0);379  LLDB_LOG(log,380           "Successfully set rendezvous breakpoint at address {0:x} "381           "for pid {1}",382           location->GetLoadAddress(),383           m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);384 385  dyld_break->SetCallback(RendezvousBreakpointHit, this, true);386  dyld_break->SetBreakpointKind("shared-library-event");387  m_dyld_bid = dyld_break->GetID();388  return true;389}390 391bool DynamicLoaderPOSIXDYLD::RendezvousBreakpointHit(392    void *baton, StoppointCallbackContext *context, user_id_t break_id,393    user_id_t break_loc_id) {394  assert(baton && "null baton");395  if (!baton)396    return false;397 398  Log *log = GetLog(LLDBLog::DynamicLoader);399  DynamicLoaderPOSIXDYLD *const dyld_instance =400      static_cast<DynamicLoaderPOSIXDYLD *>(baton);401  LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s called for pid %" PRIu64,402            __FUNCTION__,403            dyld_instance->m_process ? dyld_instance->m_process->GetID()404                                     : LLDB_INVALID_PROCESS_ID);405 406  dyld_instance->RefreshModules();407 408  // Return true to stop the target, false to just let the target run.409  const bool stop_when_images_change = dyld_instance->GetStopWhenImagesChange();410  LLDB_LOGF(log,411            "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64412            " stop_when_images_change=%s",413            __FUNCTION__,414            dyld_instance->m_process ? dyld_instance->m_process->GetID()415                                     : LLDB_INVALID_PROCESS_ID,416            stop_when_images_change ? "true" : "false");417  return stop_when_images_change;418}419 420void DynamicLoaderPOSIXDYLD::RefreshModules() {421  if (!m_rendezvous.Resolve())422    return;423 424  // The rendezvous class doesn't enumerate the main module, so track that425  // ourselves here.426  ModuleSP executable = GetTargetExecutable();427  SetLoadedModule(executable, m_rendezvous.GetLinkMapAddress());428 429  DYLDRendezvous::iterator I;430  DYLDRendezvous::iterator E;431 432  ModuleList &loaded_modules = m_process->GetTarget().GetImages();433 434  if (m_rendezvous.ModulesDidLoad() || !m_initial_modules_added) {435    ModuleList new_modules;436 437    // If this is the first time rendezvous breakpoint fires, we need438    // to take care of adding all the initial modules reported by439    // the loader.  This is necessary to list ld-linux.so on Linux,440    // and all DT_NEEDED entries on *BSD.441    if (m_initial_modules_added) {442      I = m_rendezvous.loaded_begin();443      E = m_rendezvous.loaded_end();444    } else {445      I = m_rendezvous.begin();446      E = m_rendezvous.end();447      m_initial_modules_added = true;448    }449 450    // Synchronize reading and writing of `m_interpreter_module`.451    std::mutex interpreter_module_mutex;452    // We should be able to take SOEntry as reference since the data453    // exists for the duration of this call in `m_rendezvous`.454    auto load_module_fn =455        [this, &loaded_modules, &new_modules,456         &interpreter_module_mutex](const DYLDRendezvous::SOEntry &so_entry) {457          // Don't load a duplicate copy of ld.so if we have already loaded it458          // earlier in LoadInterpreterModule. If we instead loaded then459          // unloaded it later, the section information for ld.so would be460          // removed. That information is required for placing breakpoints on461          // Arm/Thumb systems.462          {463            // `m_interpreter_module` may be modified by another thread at the464            // same time, so we guard the access here.465            std::lock_guard<std::mutex> lock(interpreter_module_mutex);466            if ((m_interpreter_module.lock() != nullptr) &&467                (so_entry.base_addr == m_interpreter_base))468              return;469          }470 471          ModuleSP module_sp = LoadModuleAtAddress(472              so_entry.file_spec, so_entry.link_addr, so_entry.base_addr,473              /*base_addr_is_offset=*/true);474          if (!module_sp.get())475            return;476 477          {478            // `m_interpreter_module` may be modified by another thread at the479            // same time, so we guard the access here.480            std::lock_guard<std::mutex> lock(interpreter_module_mutex);481            // Set the interpreter module, if this is the interpreter.482            if (module_sp->GetObjectFile()->GetBaseAddress().GetLoadAddress(483                    &m_process->GetTarget()) == m_interpreter_base) {484              ModuleSP interpreter_sp = m_interpreter_module.lock();485              if (m_interpreter_module.lock() == nullptr) {486                m_interpreter_module = module_sp;487              } else if (module_sp == interpreter_sp) {488                // Module already loaded.489                return;490              }491            }492          }493 494          // Note: in a multi-threaded environment, these module lists may be495          // appended to out-of-order. This is fine, since there's no496          // expectation for `loaded_modules` or `new_modules` to be in any497          // particular order, and appending to each module list is thread-safe.498          // Also, `new_modules` is only used for the `ModulesDidLoad` call at499          // the end of this function.500          loaded_modules.AppendIfNeeded(module_sp);501          new_modules.Append(module_sp);502        };503 504    if (m_process->GetTarget().GetParallelModuleLoad()) {505      llvm::ThreadPoolTaskGroup task_group(Debugger::GetThreadPool());506      for (; I != E; ++I)507        task_group.async(load_module_fn, *I);508      task_group.wait();509    } else {510      for (; I != E; ++I)511        load_module_fn(*I);512    }513 514    m_process->GetTarget().ModulesDidLoad(new_modules);515  }516 517  if (m_rendezvous.ModulesDidUnload()) {518    ModuleList old_modules;519 520    E = m_rendezvous.unloaded_end();521    for (I = m_rendezvous.unloaded_begin(); I != E; ++I) {522      ModuleSpec module_spec{I->file_spec};523      ModuleSP module_sp = loaded_modules.FindFirstModule(module_spec);524 525      if (module_sp.get()) {526        old_modules.Append(module_sp);527        UnloadSections(module_sp);528      }529    }530    loaded_modules.Remove(old_modules);531    m_process->GetTarget().ModulesDidUnload(old_modules, false);532  }533}534 535ThreadPlanSP536DynamicLoaderPOSIXDYLD::GetStepThroughTrampolinePlan(Thread &thread,537                                                     bool stop) {538  ThreadPlanSP thread_plan_sp;539 540  StackFrame *frame = thread.GetStackFrameAtIndex(0).get();541  const SymbolContext &context = frame->GetSymbolContext(eSymbolContextSymbol);542  Symbol *sym = context.symbol;543 544  if (sym == nullptr || !sym->IsTrampoline())545    return thread_plan_sp;546 547  ConstString sym_name = sym->GetMangled().GetName(Mangled::ePreferMangled);548  if (!sym_name)549    return thread_plan_sp;550 551  SymbolContextList target_symbols;552  Target &target = thread.GetProcess()->GetTarget();553  const ModuleList &images = target.GetImages();554 555  llvm::StringRef target_name = sym_name.GetStringRef();556  // On AArch64, the trampoline name has a prefix (__AArch64ADRPThunk_ or557  // __AArch64AbsLongThunk_) added to the function name. If we detect a558  // trampoline with the prefix, we need to remove the prefix to find the559  // function symbol.560  if (target_name.consume_front("__AArch64ADRPThunk_") ||561      target_name.consume_front("__AArch64AbsLongThunk_")) {562    // An empty target name can happen for trampolines generated for563    // section-referencing relocations.564    if (!target_name.empty()) {565      sym_name = ConstString(target_name);566    }567  }568  images.FindSymbolsWithNameAndType(sym_name, eSymbolTypeCode, target_symbols);569  if (!target_symbols.GetSize())570    return thread_plan_sp;571 572  typedef std::vector<lldb::addr_t> AddressVector;573  AddressVector addrs;574  for (const SymbolContext &context : target_symbols) {575    addr_t addr = context.GetFunctionOrSymbolAddress().GetLoadAddress(&target);576    if (addr != LLDB_INVALID_ADDRESS)577      addrs.push_back(addr);578  }579 580  if (addrs.size() > 0) {581    AddressVector::iterator start = addrs.begin();582    AddressVector::iterator end = addrs.end();583 584    llvm::sort(start, end);585    addrs.erase(std::unique(start, end), end);586    thread_plan_sp =587        std::make_shared<ThreadPlanRunToAddress>(thread, addrs, stop);588  }589 590  return thread_plan_sp;591}592 593void DynamicLoaderPOSIXDYLD::LoadVDSO() {594  if (m_vdso_base == LLDB_INVALID_ADDRESS)595    return;596 597  FileSpec file("[vdso]");598 599  MemoryRegionInfo info;600  Status status = m_process->GetMemoryRegionInfo(m_vdso_base, info);601  if (status.Fail()) {602    Log *log = GetLog(LLDBLog::DynamicLoader);603    LLDB_LOG(log, "Failed to get vdso region info: {0}", status);604    return;605  }606 607  if (ModuleSP module_sp = m_process->ReadModuleFromMemory(608          file, m_vdso_base, info.GetRange().GetByteSize())) {609    UpdateLoadedSections(module_sp, LLDB_INVALID_ADDRESS, m_vdso_base, false);610    m_process->GetTarget().GetImages().AppendIfNeeded(module_sp);611  }612}613 614ModuleSP DynamicLoaderPOSIXDYLD::LoadInterpreterModule() {615  if (m_interpreter_base == LLDB_INVALID_ADDRESS)616    return nullptr;617 618  MemoryRegionInfo info;619  Target &target = m_process->GetTarget();620  Status status = m_process->GetMemoryRegionInfo(m_interpreter_base, info);621  if (status.Fail() || info.GetMapped() != MemoryRegionInfo::eYes ||622      info.GetName().IsEmpty()) {623    Log *log = GetLog(LLDBLog::DynamicLoader);624    LLDB_LOG(log, "Failed to get interpreter region info: {0}", status);625    return nullptr;626  }627 628  FileSpec file(info.GetName().GetCString());629  ModuleSpec module_spec(file, target.GetArchitecture());630 631  // Don't notify that module is added here because its loading section632  // addresses are not updated yet. We manually notify it below.633  if (ModuleSP module_sp =634          target.GetOrCreateModule(module_spec, /*notify=*/false)) {635    UpdateLoadedSections(module_sp, LLDB_INVALID_ADDRESS, m_interpreter_base,636                         false);637    // Manually notify that dynamic linker is loaded after updating load section638    // addersses so that breakpoints can be resolved.639    ModuleList module_list;640    module_list.Append(module_sp);641    target.ModulesDidLoad(module_list);642    m_interpreter_module = module_sp;643    return module_sp;644  }645  return nullptr;646}647 648ModuleSP DynamicLoaderPOSIXDYLD::LoadModuleAtAddress(const FileSpec &file,649                                                     addr_t link_map_addr,650                                                     addr_t base_addr,651                                                     bool base_addr_is_offset) {652  if (ModuleSP module_sp = DynamicLoader::LoadModuleAtAddress(653          file, link_map_addr, base_addr, base_addr_is_offset))654    return module_sp;655 656  // This works around an dynamic linker "bug" on android <= 23, where the657  // dynamic linker would report the application name658  // (e.g. com.example.myapplication) instead of the main process binary659  // (/system/bin/app_process(32)). The logic is not sound in general (it660  // assumes base_addr is the real address, even though it actually is a load661  // bias), but it happens to work on android because app_process has a file662  // address of zero.663  // This should be removed after we drop support for android-23.664  if (m_process->GetTarget().GetArchitecture().GetTriple().isAndroid()) {665    MemoryRegionInfo memory_info;666    Status error = m_process->GetMemoryRegionInfo(base_addr, memory_info);667    if (error.Success() && memory_info.GetMapped() &&668        memory_info.GetRange().GetRangeBase() == base_addr &&669        !(memory_info.GetName().IsEmpty())) {670      if (ModuleSP module_sp = DynamicLoader::LoadModuleAtAddress(671              FileSpec(memory_info.GetName().GetStringRef()), link_map_addr,672              base_addr, base_addr_is_offset))673        return module_sp;674    }675  }676 677  return nullptr;678}679 680void DynamicLoaderPOSIXDYLD::LoadAllCurrentModules() {681  DYLDRendezvous::iterator I;682  DYLDRendezvous::iterator E;683  ModuleList module_list;684  Log *log = GetLog(LLDBLog::DynamicLoader);685 686  LoadVDSO();687 688  if (!m_rendezvous.Resolve()) {689    LLDB_LOGF(log,690              "DynamicLoaderPOSIXDYLD::%s unable to resolve POSIX DYLD "691              "rendezvous address",692              __FUNCTION__);693    return;694  }695 696  // The rendezvous class doesn't enumerate the main module, so track that697  // ourselves here.698  ModuleSP executable = GetTargetExecutable();699  SetLoadedModule(executable, m_rendezvous.GetLinkMapAddress());700 701  std::vector<FileSpec> module_names;702  for (I = m_rendezvous.begin(), E = m_rendezvous.end(); I != E; ++I)703    module_names.push_back(I->file_spec);704  m_process->PrefetchModuleSpecs(705      module_names, m_process->GetTarget().GetArchitecture().GetTriple());706 707  auto load_module_fn = [this, &module_list,708                         &log](const DYLDRendezvous::SOEntry &so_entry) {709    ModuleSP module_sp = LoadModuleAtAddress(710        so_entry.file_spec, so_entry.link_addr, so_entry.base_addr, true);711    if (module_sp.get()) {712      LLDB_LOG(log, "LoadAllCurrentModules loading module: {0}",713               so_entry.file_spec.GetFilename());714      module_list.Append(module_sp);715    } else {716      Log *log = GetLog(LLDBLog::DynamicLoader);717      LLDB_LOGF(718          log,719          "DynamicLoaderPOSIXDYLD::%s failed loading module %s at 0x%" PRIx64,720          __FUNCTION__, so_entry.file_spec.GetPath().c_str(),721          so_entry.base_addr);722    }723  };724  if (m_process->GetTarget().GetParallelModuleLoad()) {725    llvm::ThreadPoolTaskGroup task_group(Debugger::GetThreadPool());726    for (I = m_rendezvous.begin(), E = m_rendezvous.end(); I != E; ++I)727      task_group.async(load_module_fn, *I);728    task_group.wait();729  } else {730    for (I = m_rendezvous.begin(), E = m_rendezvous.end(); I != E; ++I)731      load_module_fn(*I);732  }733 734  m_process->GetTarget().ModulesDidLoad(module_list);735  m_initial_modules_added = true;736}737 738addr_t DynamicLoaderPOSIXDYLD::ComputeLoadOffset() {739  addr_t virt_entry;740 741  if (m_load_offset != LLDB_INVALID_ADDRESS)742    return m_load_offset;743 744  if ((virt_entry = GetEntryPoint()) == LLDB_INVALID_ADDRESS)745    return LLDB_INVALID_ADDRESS;746 747  ModuleSP module = m_process->GetTarget().GetExecutableModule();748  if (!module)749    return LLDB_INVALID_ADDRESS;750 751  ObjectFile *exe = module->GetObjectFile();752  if (!exe)753    return LLDB_INVALID_ADDRESS;754 755  Address file_entry = exe->GetEntryPointAddress();756 757  if (!file_entry.IsValid())758    return LLDB_INVALID_ADDRESS;759 760  m_load_offset = virt_entry - file_entry.GetFileAddress();761  return m_load_offset;762}763 764void DynamicLoaderPOSIXDYLD::EvalSpecialModulesStatus() {765  if (std::optional<uint64_t> vdso_base =766          m_auxv->GetAuxValue(AuxVector::AUXV_AT_SYSINFO_EHDR))767    m_vdso_base = *vdso_base;768 769  if (std::optional<uint64_t> interpreter_base =770          m_auxv->GetAuxValue(AuxVector::AUXV_AT_BASE))771    m_interpreter_base = *interpreter_base;772}773 774addr_t DynamicLoaderPOSIXDYLD::GetEntryPoint() {775  if (m_entry_point != LLDB_INVALID_ADDRESS)776    return m_entry_point;777 778  if (m_auxv == nullptr)779    return LLDB_INVALID_ADDRESS;780 781  std::optional<uint64_t> entry_point =782      m_auxv->GetAuxValue(AuxVector::AUXV_AT_ENTRY);783  if (!entry_point)784    return LLDB_INVALID_ADDRESS;785 786  m_entry_point = static_cast<addr_t>(*entry_point);787 788  const ArchSpec &arch = m_process->GetTarget().GetArchitecture();789 790  // On ppc64, the entry point is actually a descriptor.  Dereference it.791  if (arch.GetMachine() == llvm::Triple::ppc64)792    m_entry_point = ReadUnsignedIntWithSizeInBytes(m_entry_point, 8);793 794  return m_entry_point;795}796 797lldb::addr_t798DynamicLoaderPOSIXDYLD::GetThreadLocalData(const lldb::ModuleSP module_sp,799                                           const lldb::ThreadSP thread,800                                           lldb::addr_t tls_file_addr) {801  Log *log = GetLog(LLDBLog::DynamicLoader);802  std::optional<addr_t> link_map_addr_opt = GetLoadedModuleLinkAddr(module_sp);803  if (!link_map_addr_opt.has_value()) {804    LLDB_LOGF(805        log, "GetThreadLocalData error: module(%s) not found in loaded modules",806        module_sp->GetObjectName().AsCString());807    return LLDB_INVALID_ADDRESS;808  }809 810  addr_t link_map = link_map_addr_opt.value();811  if (link_map == LLDB_INVALID_ADDRESS || link_map == 0) {812    LLDB_LOGF(log,813              "GetThreadLocalData error: invalid link map address=0x%" PRIx64,814              link_map);815    return LLDB_INVALID_ADDRESS;816  }817 818  const DYLDRendezvous::ThreadInfo &metadata = m_rendezvous.GetThreadInfo();819  if (!metadata.valid) {820    LLDB_LOGF(log,821              "GetThreadLocalData error: fail to read thread info metadata");822    return LLDB_INVALID_ADDRESS;823  }824 825  LLDB_LOGF(log,826            "GetThreadLocalData info: link_map=0x%" PRIx64827            ", thread info metadata: "828            "modid_offset=0x%" PRIx32 ", dtv_offset=0x%" PRIx32829            ", tls_offset=0x%" PRIx32 ", dtv_slot_size=%" PRIx32 "\n",830            link_map, metadata.modid_offset, metadata.dtv_offset,831            metadata.tls_offset, metadata.dtv_slot_size);832 833  // Get the thread pointer.834  addr_t tp = thread->GetThreadPointer();835  if (tp == LLDB_INVALID_ADDRESS) {836    LLDB_LOGF(log, "GetThreadLocalData error: fail to read thread pointer");837    return LLDB_INVALID_ADDRESS;838  }839 840  // Find the module's modid.841  int modid_size = 4; // FIXME(spucci): This isn't right for big-endian 64-bit842  int64_t modid = ReadUnsignedIntWithSizeInBytes(843      link_map + metadata.modid_offset, modid_size);844  if (modid == -1) {845    LLDB_LOGF(log, "GetThreadLocalData error: fail to read modid");846    return LLDB_INVALID_ADDRESS;847  }848 849  // Lookup the DTV structure for this thread.850  addr_t dtv_ptr = tp + metadata.dtv_offset;851  addr_t dtv = ReadPointer(dtv_ptr);852  if (dtv == LLDB_INVALID_ADDRESS) {853    LLDB_LOGF(log, "GetThreadLocalData error: fail to read dtv");854    return LLDB_INVALID_ADDRESS;855  }856 857  // Find the TLS block for this module.858  addr_t dtv_slot = dtv + metadata.dtv_slot_size * modid;859  addr_t tls_block = ReadPointer(dtv_slot + metadata.tls_offset);860 861  LLDB_LOGF(log,862            "DynamicLoaderPOSIXDYLD::Performed TLS lookup: "863            "module=%s, link_map=0x%" PRIx64 ", tp=0x%" PRIx64864            ", modid=%" PRId64 ", tls_block=0x%" PRIx64 "\n",865            module_sp->GetObjectName().AsCString(""), link_map, tp,866            (int64_t)modid, tls_block);867 868  if (tls_block == LLDB_INVALID_ADDRESS) {869    LLDB_LOGF(log, "GetThreadLocalData error: fail to read tls_block");870    return LLDB_INVALID_ADDRESS;871  } else872    return tls_block + tls_file_addr;873}874 875void DynamicLoaderPOSIXDYLD::ResolveExecutableModule(876    lldb::ModuleSP &module_sp) {877  Log *log = GetLog(LLDBLog::DynamicLoader);878 879  if (m_process == nullptr)880    return;881 882  auto &target = m_process->GetTarget();883  const auto platform_sp = target.GetPlatform();884 885  ProcessInstanceInfo process_info;886  if (!m_process->GetProcessInfo(process_info)) {887    LLDB_LOGF(log,888              "DynamicLoaderPOSIXDYLD::%s - failed to get process info for "889              "pid %" PRIu64,890              __FUNCTION__, m_process->GetID());891    return;892  }893 894  LLDB_LOGF(895      log, "DynamicLoaderPOSIXDYLD::%s - got executable by pid %" PRIu64 ": %s",896      __FUNCTION__, m_process->GetID(),897      process_info.GetExecutableFile().GetPath().c_str());898 899  ModuleSpec module_spec(process_info.GetExecutableFile(),900                         process_info.GetArchitecture());901  if (module_sp && module_sp->MatchesModuleSpec(module_spec))902    return;903 904  module_spec.SetTarget(target.shared_from_this());905  const auto executable_search_paths(Target::GetDefaultExecutableSearchPaths());906  auto error = platform_sp->ResolveExecutable(module_spec, module_sp);907  if (error.Fail()) {908    StreamString stream;909    module_spec.Dump(stream);910 911    LLDB_LOGF(log,912              "DynamicLoaderPOSIXDYLD::%s - failed to resolve executable "913              "with module spec \"%s\": %s",914              __FUNCTION__, stream.GetData(), error.AsCString());915    return;916  }917 918  target.SetExecutableModule(module_sp, eLoadDependentsNo);919}920 921bool DynamicLoaderPOSIXDYLD::AlwaysRelyOnEHUnwindInfo(922    lldb_private::SymbolContext &sym_ctx) {923  ModuleSP module_sp;924  if (sym_ctx.symbol)925    module_sp = sym_ctx.symbol->GetAddressRef().GetModule();926  if (!module_sp && sym_ctx.function)927    module_sp = sym_ctx.function->GetAddress().GetModule();928  if (!module_sp)929    return false;930 931  return module_sp->GetFileSpec().GetPath() == "[vdso]";932}933 934bool DynamicLoaderPOSIXDYLD::IsCoreFile() const {935  return !m_process->IsLiveDebugSession();936}937 938// For our ELF/POSIX builds save off the fs_base/gs_base regions939static void AddThreadLocalMemoryRegions(Process &process, ThreadSP &thread_sp,940                                        std::vector<MemoryRegionInfo> &ranges) {941  lldb::RegisterContextSP reg_ctx = thread_sp->GetRegisterContext();942  if (!reg_ctx)943    return;944 945  const RegisterInfo *reg_info = reg_ctx->GetRegisterInfo(946      lldb::RegisterKind::eRegisterKindGeneric, LLDB_REGNUM_GENERIC_TP);947  if (!reg_info)948    return;949 950  lldb_private::RegisterValue thread_local_register_value;951  bool success = reg_ctx->ReadRegister(reg_info, thread_local_register_value);952  if (!success)953    return;954 955  const uint64_t fail_value = UINT64_MAX;956  bool readSuccess = false;957  const lldb::addr_t reg_value_addr =958      thread_local_register_value.GetAsUInt64(fail_value, &readSuccess);959  if (!readSuccess || reg_value_addr == fail_value)960    return;961 962  MemoryRegionInfo thread_local_region;963  Status err = process.GetMemoryRegionInfo(reg_value_addr, thread_local_region);964  if (err.Fail())965    return;966 967  ranges.push_back(thread_local_region);968}969 970// Save off the link map for core files.971static void AddLinkMapSections(Process &process,972                               std::vector<MemoryRegionInfo> &ranges) {973  ModuleList &module_list = process.GetTarget().GetImages();974  Target *target = &process.GetTarget();975  for (size_t idx = 0; idx < module_list.GetSize(); idx++) {976    ModuleSP module_sp = module_list.GetModuleAtIndex(idx);977    if (!module_sp)978      continue;979 980    ObjectFile *obj = module_sp->GetObjectFile();981    if (!obj)982      continue;983    Address addr = obj->GetImageInfoAddress(target);984    addr_t load_addr = addr.GetLoadAddress(target);985    if (load_addr == LLDB_INVALID_ADDRESS)986      continue;987 988    MemoryRegionInfo link_map_section;989    Status err = process.GetMemoryRegionInfo(load_addr, link_map_section);990    if (err.Fail())991      continue;992 993    ranges.push_back(link_map_section);994  }995}996 997void DynamicLoaderPOSIXDYLD::CalculateDynamicSaveCoreRanges(998    lldb_private::Process &process,999    std::vector<lldb_private::MemoryRegionInfo> &ranges,1000    llvm::function_ref<bool(const lldb_private::Thread &)>1001        save_thread_predicate) {1002  ThreadList &thread_list = process.GetThreadList();1003  for (size_t idx = 0; idx < thread_list.GetSize(); idx++) {1004    ThreadSP thread_sp = thread_list.GetThreadAtIndex(idx);1005    if (!thread_sp)1006      continue;1007 1008    if (!save_thread_predicate(*thread_sp))1009      continue;1010 1011    AddThreadLocalMemoryRegions(process, thread_sp, ranges);1012  }1013 1014  AddLinkMapSections(process, ranges);1015}1016