src/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cc

   1 //===-- sanitizer_symbolizer_win.cc ---------------------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file is shared between AddressSanitizer and ThreadSanitizer
  11 // run-time libraries.
  12 // Windows-specific implementation of symbolizer parts.
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "sanitizer_platform.h"
  16 #if SANITIZER_WINDOWS
  17 #define WIN32_LEAN_AND_MEAN
  18 #include <windows.h>
  19 #include <dbghelp.h>
  20 #pragma comment(lib, "dbghelp.lib")
  21
  22 #include "sanitizer_symbolizer_internal.h"
  23
  24 namespace __sanitizer {
  25
  26 namespace {
  27
  28 class WinSymbolizerTool : public SymbolizerTool {
  29  public:
  30   bool SymbolizePC(uptr addr, SymbolizedStack *stack) override;
  31   bool SymbolizeData(uptr addr, DataInfo *info) override {
  32     return false;
  33   }
  34   const char *Demangle(const char *name) override;
  35 };
  36
  37 bool is_dbghelp_initialized = false;
  38
  39 bool TrySymInitialize() {
  40   SymSetOptions(SYMOPT_DEFERRED_LOADS | SYMOPT_UNDNAME | SYMOPT_LOAD_LINES);
  41   return SymInitialize(GetCurrentProcess(), 0, TRUE);
  42   // FIXME: We don't call SymCleanup() on exit yet - should we?
  43 }
  44
  45 // Initializes DbgHelp library, if it's not yet initialized. Calls to this
  46 // function should be synchronized with respect to other calls to DbgHelp API
  47 // (e.g. from WinSymbolizerTool).
  48 void InitializeDbgHelpIfNeeded() {
  49   if (is_dbghelp_initialized)
  50     return;
  51   if (!TrySymInitialize()) {
  52     // OK, maybe the client app has called SymInitialize already.
  53     // That's a bit unfortunate for us as all the DbgHelp functions are
  54     // single-threaded and we can't coordinate with the app.
  55     // FIXME: Can we stop the other threads at this point?
  56     // Anyways, we have to reconfigure stuff to make sure that SymInitialize
  57     // has all the appropriate options set.
  58     // Cross our fingers and reinitialize DbgHelp.
  59     Report("*** WARNING: Failed to initialize DbgHelp!              ***\n");
  60     Report("*** Most likely this means that the app is already      ***\n");
  61     Report("*** using DbgHelp, possibly with incompatible flags.    ***\n");
  62     Report("*** Due to technical reasons, symbolization might crash ***\n");
  63     Report("*** or produce wrong results.                           ***\n");
  64     SymCleanup(GetCurrentProcess());
  65     TrySymInitialize();
  66   }
  67   is_dbghelp_initialized = true;
  68
  69   // When an executable is run from a location different from the one where it
  70   // was originally built, we may not see the nearby PDB files.
  71   // To work around this, let's append the directory of the main module
  72   // to the symbol search path.  All the failures below are not fatal.
  73   const size_t kSymPathSize = 2048;
  74   static wchar_t path_buffer[kSymPathSize + 1 + MAX_PATH];
  75   if (!SymGetSearchPathW(GetCurrentProcess(), path_buffer, kSymPathSize)) {
  76     Report("*** WARNING: Failed to SymGetSearchPathW ***\n");
  77     return;
  78   }
  79   size_t sz = wcslen(path_buffer);
  80   if (sz) {
  81     CHECK_EQ(0, wcscat_s(path_buffer, L";"));
  82     sz++;
  83   }
  84   DWORD res = GetModuleFileNameW(NULL, path_buffer + sz, MAX_PATH);
  85   if (res == 0 || res == MAX_PATH) {
  86     Report("*** WARNING: Failed to getting the EXE directory ***\n");
  87     return;
  88   }
  89   // Write the zero character in place of the last backslash to get the
  90   // directory of the main module at the end of path_buffer.
  91   wchar_t *last_bslash = wcsrchr(path_buffer + sz, L'\\');
  92   CHECK_NE(last_bslash, 0);
  93   *last_bslash = L'\0';
  94   if (!SymSetSearchPathW(GetCurrentProcess(), path_buffer)) {
  95     Report("*** WARNING: Failed to SymSetSearchPathW\n");
  96     return;
  97   }
  98 }
  99
 100 }  // namespace
 101
 102 bool WinSymbolizerTool::SymbolizePC(uptr addr, SymbolizedStack *frame) {
 103   InitializeDbgHelpIfNeeded();
 104
 105   // See http://msdn.microsoft.com/en-us/library/ms680578(VS.85).aspx
 106   char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(CHAR)];
 107   PSYMBOL_INFO symbol = (PSYMBOL_INFO)buffer;
 108   symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
 109   symbol->MaxNameLen = MAX_SYM_NAME;
 110   DWORD64 offset = 0;
 111   BOOL got_objname = SymFromAddr(GetCurrentProcess(),
 112                                  (DWORD64)addr, &offset, symbol);
 113   if (!got_objname)
 114     return false;
 115
 116   DWORD unused;
 117   IMAGEHLP_LINE64 line_info;
 118   line_info.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
 119   BOOL got_fileline = SymGetLineFromAddr64(GetCurrentProcess(), (DWORD64)addr,
 120                                            &unused, &line_info);
 121   frame->info.function = internal_strdup(symbol->Name);
 122   frame->info.function_offset = (uptr)offset;
 123   if (got_fileline) {
 124     frame->info.file = internal_strdup(line_info.FileName);
 125     frame->info.line = line_info.LineNumber;
 126   }
 127   // Only consider this a successful symbolization attempt if we got file info.
 128   // Otherwise, try llvm-symbolizer.
 129   return got_fileline;
 130 }
 131
 132 const char *WinSymbolizerTool::Demangle(const char *name) {
 133   CHECK(is_dbghelp_initialized);
 134   static char demangle_buffer[1000];
 135   if (name[0] == '\01' &&
 136       UnDecorateSymbolName(name + 1, demangle_buffer, sizeof(demangle_buffer),
 137                            UNDNAME_NAME_ONLY))
 138     return demangle_buffer;
 139   else
 140     return name;
 141 }
 142
 143 const char *Symbolizer::PlatformDemangle(const char *name) {
 144   return name;
 145 }
 146
 147 void Symbolizer::PlatformPrepareForSandboxing() {
 148   // Do nothing.
 149 }
 150
 151 namespace {
 152 struct ScopedHandle {
 153   ScopedHandle() : h_(nullptr) {}
 154   explicit ScopedHandle(HANDLE h) : h_(h) {}
 155   ~ScopedHandle() {
 156     if (h_)
 157       ::CloseHandle(h_);
 158   }
 159   HANDLE get() { return h_; }
 160   HANDLE *receive() { return &h_; }
 161   HANDLE release() {
 162     HANDLE h = h_;
 163     h_ = nullptr;
 164     return h;
 165   }
 166   HANDLE h_;
 167 };
 168 } // namespace
 169
 170 bool SymbolizerProcess::StartSymbolizerSubprocess() {
 171   // Create inherited pipes for stdin and stdout.
 172   ScopedHandle stdin_read, stdin_write;
 173   ScopedHandle stdout_read, stdout_write;
 174   SECURITY_ATTRIBUTES attrs;
 175   attrs.nLength = sizeof(SECURITY_ATTRIBUTES);
 176   attrs.bInheritHandle = TRUE;
 177   attrs.lpSecurityDescriptor = nullptr;
 178   if (!::CreatePipe(stdin_read.receive(), stdin_write.receive(), &attrs, 0) ||
 179       !::CreatePipe(stdout_read.receive(), stdout_write.receive(), &attrs, 0)) {
 180     VReport(2, "WARNING: %s CreatePipe failed (error code: %d)\n",
 181             SanitizerToolName, path_, GetLastError());
 182     return false;
 183   }
 184
 185   // Don't inherit the writing end of stdin or the reading end of stdout.
 186   if (!SetHandleInformation(stdin_write.get(), HANDLE_FLAG_INHERIT, 0) ||
 187       !SetHandleInformation(stdout_read.get(), HANDLE_FLAG_INHERIT, 0)) {
 188     VReport(2, "WARNING: %s SetHandleInformation failed (error code: %d)\n",
 189             SanitizerToolName, path_, GetLastError());
 190     return false;
 191   }
 192
 193   // Compute the command line. Wrap double quotes around everything.
 194   const char *argv[kArgVMax];
 195   GetArgV(path_, argv);
 196   InternalScopedString command_line(kMaxPathLength * 3);
 197   for (int i = 0; argv[i]; i++) {
 198     const char *arg = argv[i];
 199     int arglen = internal_strlen(arg);
 200     // Check that tool command lines are simple and that complete escaping is
 201     // unnecessary.
 202     CHECK(!internal_strchr(arg, '"') && "quotes in args unsupported");
 203     CHECK(!internal_strstr(arg, "\\\\") &&
 204           "double backslashes in args unsupported");
 205     CHECK(arglen > 0 && arg[arglen - 1] != '\\' &&
 206           "args ending in backslash and empty args unsupported");
 207     command_line.append("\"%s\" ", arg);
 208   }
 209   VReport(3, "Launching symbolizer command: %s\n", command_line.data());
 210
 211   // Launch llvm-symbolizer with stdin and stdout redirected.
 212   STARTUPINFOA si;
 213   memset(&si, 0, sizeof(si));
 214   si.cb = sizeof(si);
 215   si.dwFlags |= STARTF_USESTDHANDLES;
 216   si.hStdInput = stdin_read.get();
 217   si.hStdOutput = stdout_write.get();
 218   PROCESS_INFORMATION pi;
 219   memset(&pi, 0, sizeof(pi));
 220   if (!CreateProcessA(path_,               // Executable
 221                       command_line.data(), // Command line
 222                       nullptr,             // Process handle not inheritable
 223                       nullptr,             // Thread handle not inheritable
 224                       TRUE,                // Set handle inheritance to TRUE
 225                       0,                   // Creation flags
 226                       nullptr,             // Use parent's environment block
 227                       nullptr,             // Use parent's starting directory
 228                       &si, &pi)) {
 229     VReport(2, "WARNING: %s failed to create process for %s (error code: %d)\n",
 230             SanitizerToolName, path_, GetLastError());
 231     return false;
 232   }
 233
 234   // Process creation succeeded, so transfer handle ownership into the fields.
 235   input_fd_ = stdout_read.release();
 236   output_fd_ = stdin_write.release();
 237
 238   // The llvm-symbolizer process is responsible for quitting itself when the
 239   // stdin pipe is closed, so we don't need these handles. Close them to prevent
 240   // leaks. If we ever want to try to kill the symbolizer process from the
 241   // parent, we'll want to hang on to these handles.
 242   CloseHandle(pi.hProcess);
 243   CloseHandle(pi.hThread);
 244   return true;
 245 }
 246
 247 static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
 248                                   LowLevelAllocator *allocator) {
 249   if (!common_flags()->symbolize) {
 250     VReport(2, "Symbolizer is disabled.\n");
 251     return;
 252   }
 253
 254   // Add llvm-symbolizer in case the binary has dwarf.
 255   const char *user_path = common_flags()->external_symbolizer_path;
 256   const char *path =
 257       user_path ? user_path : FindPathToBinary("llvm-symbolizer.exe");
 258   if (path) {
 259     VReport(2, "Using llvm-symbolizer at %spath: %s\n",
 260             user_path ? "user-specified " : "", path);
 261     list->push_back(new(*allocator) LLVMSymbolizer(path, allocator));
 262   } else {
 263     if (user_path && user_path[0] == '\0') {
 264       VReport(2, "External symbolizer is explicitly disabled.\n");
 265     } else {
 266       VReport(2, "External symbolizer is not present.\n");
 267     }
 268   }
 269
 270   // Add the dbghelp based symbolizer.
 271   list->push_back(new(*allocator) WinSymbolizerTool());
 272 }
 273
 274 Symbolizer *Symbolizer::PlatformInit() {
 275   IntrusiveList<SymbolizerTool> list;
 276   list.clear();
 277   ChooseSymbolizerTools(&list, &symbolizer_allocator_);
 278
 279   return new(symbolizer_allocator_) Symbolizer(list);
 280 }
 281
 282 }  // namespace __sanitizer
 283
 284 #endif  // _WIN32