1 //===-- sanitizer_symbolizer_win.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 // This file is shared between AddressSanitizer and ThreadSanitizer
10 // run-time libraries.
11 // Windows-specific implementation of symbolizer parts.
12 //===----------------------------------------------------------------------===//
13
14 #include "sanitizer_platform.h"
15 #if SANITIZER_WINDOWS
16
17 #include "sanitizer_dbghelp.h"
18 #include "sanitizer_symbolizer_internal.h"
19
20 namespace __sanitizer {
21
22 decltype(::StackWalk64) *StackWalk64;
23 decltype(::SymCleanup) *SymCleanup;
24 decltype(::SymFromAddr) *SymFromAddr;
25 decltype(::SymFunctionTableAccess64) *SymFunctionTableAccess64;
26 decltype(::SymGetLineFromAddr64) *SymGetLineFromAddr64;
27 decltype(::SymGetModuleBase64) *SymGetModuleBase64;
28 decltype(::SymGetSearchPathW) *SymGetSearchPathW;
29 decltype(::SymInitialize) *SymInitialize;
30 decltype(::SymSetOptions) *SymSetOptions;
31 decltype(::SymSetSearchPathW) *SymSetSearchPathW;
32 decltype(::UnDecorateSymbolName) *UnDecorateSymbolName;
33
34 namespace {
35
36 class WinSymbolizerTool final : public SymbolizerTool {
37 public:
38 // The constructor is provided to avoid synthesized memsets.
WinSymbolizerTool()39 WinSymbolizerTool() {}
40
41 bool SymbolizePC(uptr addr, SymbolizedStack *stack) override;
SymbolizeData(uptr addr,DataInfo * info)42 bool SymbolizeData(uptr addr, DataInfo *info) override {
43 return false;
44 }
45 const char *Demangle(const char *name) override;
46 };
47
48 bool is_dbghelp_initialized = false;
49
TrySymInitialize()50 bool TrySymInitialize() {
51 SymSetOptions(SYMOPT_DEFERRED_LOADS | SYMOPT_UNDNAME | SYMOPT_LOAD_LINES);
52 return SymInitialize(GetCurrentProcess(), 0, TRUE);
53 // FIXME: We don't call SymCleanup() on exit yet - should we?
54 }
55
56 } // namespace
57
58 // Initializes DbgHelp library, if it's not yet initialized. Calls to this
59 // function should be synchronized with respect to other calls to DbgHelp API
60 // (e.g. from WinSymbolizerTool).
InitializeDbgHelpIfNeeded()61 void InitializeDbgHelpIfNeeded() {
62 if (is_dbghelp_initialized)
63 return;
64
65 HMODULE dbghelp = LoadLibraryA("dbghelp.dll");
66 CHECK(dbghelp && "failed to load dbghelp.dll");
67
68 #define DBGHELP_IMPORT(name) \
69 do { \
70 name = \
71 reinterpret_cast<decltype(::name) *>(GetProcAddress(dbghelp, #name)); \
72 CHECK(name != nullptr); \
73 } while (0)
74 DBGHELP_IMPORT(StackWalk64);
75 DBGHELP_IMPORT(SymCleanup);
76 DBGHELP_IMPORT(SymFromAddr);
77 DBGHELP_IMPORT(SymFunctionTableAccess64);
78 DBGHELP_IMPORT(SymGetLineFromAddr64);
79 DBGHELP_IMPORT(SymGetModuleBase64);
80 DBGHELP_IMPORT(SymGetSearchPathW);
81 DBGHELP_IMPORT(SymInitialize);
82 DBGHELP_IMPORT(SymSetOptions);
83 DBGHELP_IMPORT(SymSetSearchPathW);
84 DBGHELP_IMPORT(UnDecorateSymbolName);
85 #undef DBGHELP_IMPORT
86
87 if (!TrySymInitialize()) {
88 // OK, maybe the client app has called SymInitialize already.
89 // That's a bit unfortunate for us as all the DbgHelp functions are
90 // single-threaded and we can't coordinate with the app.
91 // FIXME: Can we stop the other threads at this point?
92 // Anyways, we have to reconfigure stuff to make sure that SymInitialize
93 // has all the appropriate options set.
94 // Cross our fingers and reinitialize DbgHelp.
95 Report("*** WARNING: Failed to initialize DbgHelp! ***\n");
96 Report("*** Most likely this means that the app is already ***\n");
97 Report("*** using DbgHelp, possibly with incompatible flags. ***\n");
98 Report("*** Due to technical reasons, symbolization might crash ***\n");
99 Report("*** or produce wrong results. ***\n");
100 SymCleanup(GetCurrentProcess());
101 TrySymInitialize();
102 }
103 is_dbghelp_initialized = true;
104
105 // When an executable is run from a location different from the one where it
106 // was originally built, we may not see the nearby PDB files.
107 // To work around this, let's append the directory of the main module
108 // to the symbol search path. All the failures below are not fatal.
109 const size_t kSymPathSize = 2048;
110 static wchar_t path_buffer[kSymPathSize + 1 + MAX_PATH];
111 if (!SymGetSearchPathW(GetCurrentProcess(), path_buffer, kSymPathSize)) {
112 Report("*** WARNING: Failed to SymGetSearchPathW ***\n");
113 return;
114 }
115 size_t sz = wcslen(path_buffer);
116 if (sz) {
117 CHECK_EQ(0, wcscat_s(path_buffer, L";"));
118 sz++;
119 }
120 DWORD res = GetModuleFileNameW(NULL, path_buffer + sz, MAX_PATH);
121 if (res == 0 || res == MAX_PATH) {
122 Report("*** WARNING: Failed to getting the EXE directory ***\n");
123 return;
124 }
125 // Write the zero character in place of the last backslash to get the
126 // directory of the main module at the end of path_buffer.
127 wchar_t *last_bslash = wcsrchr(path_buffer + sz, L'\\');
128 CHECK_NE(last_bslash, 0);
129 *last_bslash = L'\0';
130 if (!SymSetSearchPathW(GetCurrentProcess(), path_buffer)) {
131 Report("*** WARNING: Failed to SymSetSearchPathW\n");
132 return;
133 }
134 }
135
SymbolizePC(uptr addr,SymbolizedStack * frame)136 bool WinSymbolizerTool::SymbolizePC(uptr addr, SymbolizedStack *frame) {
137 InitializeDbgHelpIfNeeded();
138
139 // See http://msdn.microsoft.com/en-us/library/ms680578(VS.85).aspx
140 char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(CHAR)];
141 PSYMBOL_INFO symbol = (PSYMBOL_INFO)buffer;
142 symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
143 symbol->MaxNameLen = MAX_SYM_NAME;
144 DWORD64 offset = 0;
145 BOOL got_objname = SymFromAddr(GetCurrentProcess(),
146 (DWORD64)addr, &offset, symbol);
147 if (!got_objname)
148 return false;
149
150 DWORD unused;
151 IMAGEHLP_LINE64 line_info;
152 line_info.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
153 BOOL got_fileline = SymGetLineFromAddr64(GetCurrentProcess(), (DWORD64)addr,
154 &unused, &line_info);
155 frame->info.function = internal_strdup(symbol->Name);
156 frame->info.function_offset = (uptr)offset;
157 if (got_fileline) {
158 frame->info.file = internal_strdup(line_info.FileName);
159 frame->info.line = line_info.LineNumber;
160 }
161 // Only consider this a successful symbolization attempt if we got file info.
162 // Otherwise, try llvm-symbolizer.
163 return got_fileline;
164 }
165
Demangle(const char * name)166 const char *WinSymbolizerTool::Demangle(const char *name) {
167 CHECK(is_dbghelp_initialized);
168 static char demangle_buffer[1000];
169 if (name[0] == '\01' &&
170 UnDecorateSymbolName(name + 1, demangle_buffer, sizeof(demangle_buffer),
171 UNDNAME_NAME_ONLY))
172 return demangle_buffer;
173 else
174 return name;
175 }
176
PlatformDemangle(const char * name)177 const char *Symbolizer::PlatformDemangle(const char *name) {
178 return name;
179 }
180
181 namespace {
182 struct ScopedHandle {
ScopedHandle__sanitizer::__anonb587223f0211::ScopedHandle183 ScopedHandle() : h_(nullptr) {}
ScopedHandle__sanitizer::__anonb587223f0211::ScopedHandle184 explicit ScopedHandle(HANDLE h) : h_(h) {}
~ScopedHandle__sanitizer::__anonb587223f0211::ScopedHandle185 ~ScopedHandle() {
186 if (h_)
187 ::CloseHandle(h_);
188 }
get__sanitizer::__anonb587223f0211::ScopedHandle189 HANDLE get() { return h_; }
receive__sanitizer::__anonb587223f0211::ScopedHandle190 HANDLE *receive() { return &h_; }
release__sanitizer::__anonb587223f0211::ScopedHandle191 HANDLE release() {
192 HANDLE h = h_;
193 h_ = nullptr;
194 return h;
195 }
196 HANDLE h_;
197 };
198 } // namespace
199
StartSymbolizerSubprocess()200 bool SymbolizerProcess::StartSymbolizerSubprocess() {
201 // Create inherited pipes for stdin and stdout.
202 ScopedHandle stdin_read, stdin_write;
203 ScopedHandle stdout_read, stdout_write;
204 SECURITY_ATTRIBUTES attrs;
205 attrs.nLength = sizeof(SECURITY_ATTRIBUTES);
206 attrs.bInheritHandle = TRUE;
207 attrs.lpSecurityDescriptor = nullptr;
208 if (!::CreatePipe(stdin_read.receive(), stdin_write.receive(), &attrs, 0) ||
209 !::CreatePipe(stdout_read.receive(), stdout_write.receive(), &attrs, 0)) {
210 VReport(2, "WARNING: %s CreatePipe failed (error code: %d)\n",
211 SanitizerToolName, path_, GetLastError());
212 return false;
213 }
214
215 // Don't inherit the writing end of stdin or the reading end of stdout.
216 if (!SetHandleInformation(stdin_write.get(), HANDLE_FLAG_INHERIT, 0) ||
217 !SetHandleInformation(stdout_read.get(), HANDLE_FLAG_INHERIT, 0)) {
218 VReport(2, "WARNING: %s SetHandleInformation failed (error code: %d)\n",
219 SanitizerToolName, path_, GetLastError());
220 return false;
221 }
222
223 // Compute the command line. Wrap double quotes around everything.
224 const char *argv[kArgVMax];
225 GetArgV(path_, argv);
226 InternalScopedString command_line(kMaxPathLength * 3);
227 for (int i = 0; argv[i]; i++) {
228 const char *arg = argv[i];
229 int arglen = internal_strlen(arg);
230 // Check that tool command lines are simple and that complete escaping is
231 // unnecessary.
232 CHECK(!internal_strchr(arg, '"') && "quotes in args unsupported");
233 CHECK(!internal_strstr(arg, "\\\\") &&
234 "double backslashes in args unsupported");
235 CHECK(arglen > 0 && arg[arglen - 1] != '\\' &&
236 "args ending in backslash and empty args unsupported");
237 command_line.append("\"%s\" ", arg);
238 }
239 VReport(3, "Launching symbolizer command: %s\n", command_line.data());
240
241 // Launch llvm-symbolizer with stdin and stdout redirected.
242 STARTUPINFOA si;
243 memset(&si, 0, sizeof(si));
244 si.cb = sizeof(si);
245 si.dwFlags |= STARTF_USESTDHANDLES;
246 si.hStdInput = stdin_read.get();
247 si.hStdOutput = stdout_write.get();
248 PROCESS_INFORMATION pi;
249 memset(&pi, 0, sizeof(pi));
250 if (!CreateProcessA(path_, // Executable
251 command_line.data(), // Command line
252 nullptr, // Process handle not inheritable
253 nullptr, // Thread handle not inheritable
254 TRUE, // Set handle inheritance to TRUE
255 0, // Creation flags
256 nullptr, // Use parent's environment block
257 nullptr, // Use parent's starting directory
258 &si, &pi)) {
259 VReport(2, "WARNING: %s failed to create process for %s (error code: %d)\n",
260 SanitizerToolName, path_, GetLastError());
261 return false;
262 }
263
264 // Process creation succeeded, so transfer handle ownership into the fields.
265 input_fd_ = stdout_read.release();
266 output_fd_ = stdin_write.release();
267
268 // The llvm-symbolizer process is responsible for quitting itself when the
269 // stdin pipe is closed, so we don't need these handles. Close them to prevent
270 // leaks. If we ever want to try to kill the symbolizer process from the
271 // parent, we'll want to hang on to these handles.
272 CloseHandle(pi.hProcess);
273 CloseHandle(pi.hThread);
274 return true;
275 }
276
ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> * list,LowLevelAllocator * allocator)277 static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
278 LowLevelAllocator *allocator) {
279 if (!common_flags()->symbolize) {
280 VReport(2, "Symbolizer is disabled.\n");
281 return;
282 }
283
284 // Add llvm-symbolizer in case the binary has dwarf.
285 const char *user_path = common_flags()->external_symbolizer_path;
286 const char *path =
287 user_path ? user_path : FindPathToBinary("llvm-symbolizer.exe");
288 if (path) {
289 VReport(2, "Using llvm-symbolizer at %spath: %s\n",
290 user_path ? "user-specified " : "", path);
291 list->push_back(new(*allocator) LLVMSymbolizer(path, allocator));
292 } else {
293 if (user_path && user_path[0] == '\0') {
294 VReport(2, "External symbolizer is explicitly disabled.\n");
295 } else {
296 VReport(2, "External symbolizer is not present.\n");
297 }
298 }
299
300 // Add the dbghelp based symbolizer.
301 list->push_back(new(*allocator) WinSymbolizerTool());
302 }
303
PlatformInit()304 Symbolizer *Symbolizer::PlatformInit() {
305 IntrusiveList<SymbolizerTool> list;
306 list.clear();
307 ChooseSymbolizerTools(&list, &symbolizer_allocator_);
308
309 return new(symbolizer_allocator_) Symbolizer(list);
310 }
311
LateInitialize()312 void Symbolizer::LateInitialize() {
313 Symbolizer::GetOrInit()->LateInitializeTools();
314 }
315
316 } // namespace __sanitizer
317
318 #endif // _WIN32
319