libsanitizer/asan/asan_win.cc

   1 //===-- asan_win.cc -------------------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of AddressSanitizer, an address sanity checker.
   9 //
  10 // Windows-specific details.
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "sanitizer_common/sanitizer_platform.h"
  14 #if SANITIZER_WINDOWS
  15 #include <windows.h>
  16
  17 #include <stdlib.h>
  18
  19 #include "asan_interceptors.h"
  20 #include "asan_internal.h"
  21 #include "asan_report.h"
  22 #include "asan_stack.h"
  23 #include "asan_thread.h"
  24 #include "sanitizer_common/sanitizer_libc.h"
  25 #include "sanitizer_common/sanitizer_mutex.h"
  26
  27 using namespace __asan;  // NOLINT
  28
  29 extern "C" {
  30 SANITIZER_INTERFACE_ATTRIBUTE
  31 int __asan_should_detect_stack_use_after_return() {
  32   __asan_init();
  33   return __asan_option_detect_stack_use_after_return;
  34 }
  35
  36 // -------------------- A workaround for the abscence of weak symbols ----- {{{
  37 // We don't have a direct equivalent of weak symbols when using MSVC, but we can
  38 // use the /alternatename directive to tell the linker to default a specific
  39 // symbol to a specific value, which works nicely for allocator hooks and
  40 // __asan_default_options().
  41 void __sanitizer_default_malloc_hook(void *ptr, uptr size) { }
  42 void __sanitizer_default_free_hook(void *ptr) { }
  43 const char* __asan_default_default_options() { return ""; }
  44 const char* __asan_default_default_suppressions() { return ""; }
  45 void __asan_default_on_error() {}
  46 #pragma comment(linker, "/alternatename:___sanitizer_malloc_hook=___sanitizer_default_malloc_hook")  // NOLINT
  47 #pragma comment(linker, "/alternatename:___sanitizer_free_hook=___sanitizer_default_free_hook")      // NOLINT
  48 #pragma comment(linker, "/alternatename:___asan_default_options=___asan_default_default_options")    // NOLINT
  49 #pragma comment(linker, "/alternatename:___asan_default_suppressions=___asan_default_default_suppressions")    // NOLINT
  50 #pragma comment(linker, "/alternatename:___asan_on_error=___asan_default_on_error")                  // NOLINT
  51 // }}}
  52 }  // extern "C"
  53
  54 // ---------------------- Windows-specific inteceptors ---------------- {{{
  55 INTERCEPTOR_WINAPI(void, RaiseException, void *a, void *b, void *c, void *d) {
  56   CHECK(REAL(RaiseException));
  57   __asan_handle_no_return();
  58   REAL(RaiseException)(a, b, c, d);
  59 }
  60
  61 INTERCEPTOR(int, _except_handler3, void *a, void *b, void *c, void *d) {
  62   CHECK(REAL(_except_handler3));
  63   __asan_handle_no_return();
  64   return REAL(_except_handler3)(a, b, c, d);
  65 }
  66
  67 #if ASAN_DYNAMIC
  68 // This handler is named differently in -MT and -MD CRTs.
  69 #define _except_handler4 _except_handler4_common
  70 #endif
  71 INTERCEPTOR(int, _except_handler4, void *a, void *b, void *c, void *d) {
  72   CHECK(REAL(_except_handler4));
  73   __asan_handle_no_return();
  74   return REAL(_except_handler4)(a, b, c, d);
  75 }
  76
  77 static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
  78   AsanThread *t = (AsanThread*)arg;
  79   SetCurrentThread(t);
  80   return t->ThreadStart(GetTid(), /* signal_thread_is_registered */ nullptr);
  81 }
  82
  83 INTERCEPTOR_WINAPI(DWORD, CreateThread,
  84                    void* security, uptr stack_size,
  85                    DWORD (__stdcall *start_routine)(void*), void* arg,
  86                    DWORD thr_flags, void* tid) {
  87   // Strict init-order checking is thread-hostile.
  88   if (flags()->strict_init_order)
  89     StopInitOrderChecking();
  90   GET_STACK_TRACE_THREAD;
  91   // FIXME: The CreateThread interceptor is not the same as a pthread_create
  92   // one.  This is a bandaid fix for PR22025.
  93   bool detached = false;  // FIXME: how can we determine it on Windows?
  94   u32 current_tid = GetCurrentTidOrInvalid();
  95   AsanThread *t =
  96         AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
  97   return REAL(CreateThread)(security, stack_size,
  98                             asan_thread_start, t, thr_flags, tid);
  99 }
 100
 101 namespace {
 102 BlockingMutex mu_for_thread_tracking(LINKER_INITIALIZED);
 103
 104 void EnsureWorkerThreadRegistered() {
 105   // FIXME: GetCurrentThread relies on TSD, which might not play well with
 106   // system thread pools.  We might want to use something like reference
 107   // counting to zero out GetCurrentThread() underlying storage when the last
 108   // work item finishes?  Or can we disable reclaiming of threads in the pool?
 109   BlockingMutexLock l(&mu_for_thread_tracking);
 110   if (__asan::GetCurrentThread())
 111     return;
 112
 113   AsanThread *t = AsanThread::Create(
 114       /* start_routine */ nullptr, /* arg */ nullptr,
 115       /* parent_tid */ -1, /* stack */ nullptr, /* detached */ true);
 116   t->Init();
 117   asanThreadRegistry().StartThread(t->tid(), 0, 0);
 118   SetCurrentThread(t);
 119 }
 120 }  // namespace
 121
 122 INTERCEPTOR_WINAPI(DWORD, NtWaitForWorkViaWorkerFactory, DWORD a, DWORD b) {
 123   // NtWaitForWorkViaWorkerFactory is called from system worker pool threads to
 124   // query work scheduled by BindIoCompletionCallback, QueueUserWorkItem, etc.
 125   // System worker pool threads are created at arbitraty point in time and
 126   // without using CreateThread, so we wrap NtWaitForWorkViaWorkerFactory
 127   // instead and don't register a specific parent_tid/stack.
 128   EnsureWorkerThreadRegistered();
 129   return REAL(NtWaitForWorkViaWorkerFactory)(a, b);
 130 }
 131
 132 // }}}
 133
 134 namespace __asan {
 135
 136 void InitializePlatformInterceptors() {
 137   ASAN_INTERCEPT_FUNC(CreateThread);
 138   ASAN_INTERCEPT_FUNC(RaiseException);
 139   ASAN_INTERCEPT_FUNC(_except_handler3);
 140   ASAN_INTERCEPT_FUNC(_except_handler4);
 141
 142   // NtWaitForWorkViaWorkerFactory is always linked dynamically.
 143   CHECK(::__interception::OverrideFunction(
 144       "NtWaitForWorkViaWorkerFactory",
 145       (uptr)WRAP(NtWaitForWorkViaWorkerFactory),
 146       (uptr *)&REAL(NtWaitForWorkViaWorkerFactory)));
 147 }
 148
 149 // ---------------------- TSD ---------------- {{{
 150 static bool tsd_key_inited = false;
 151
 152 static __declspec(thread) void *fake_tsd = 0;
 153
 154 void AsanTSDInit(void (*destructor)(void *tsd)) {
 155   // FIXME: we're ignoring the destructor for now.
 156   tsd_key_inited = true;
 157 }
 158
 159 void *AsanTSDGet() {
 160   CHECK(tsd_key_inited);
 161   return fake_tsd;
 162 }
 163
 164 void AsanTSDSet(void *tsd) {
 165   CHECK(tsd_key_inited);
 166   fake_tsd = tsd;
 167 }
 168
 169 void PlatformTSDDtor(void *tsd) {
 170   AsanThread::TSDDtor(tsd);
 171 }
 172 // }}}
 173
 174 // ---------------------- Various stuff ---------------- {{{
 175 void DisableReexec() {
 176   // No need to re-exec on Windows.
 177 }
 178
 179 void MaybeReexec() {
 180   // No need to re-exec on Windows.
 181 }
 182
 183 void *AsanDoesNotSupportStaticLinkage() {
 184 #if defined(_DEBUG)
 185 #error Please build the runtime with a non-debug CRT: /MD or /MT
 186 #endif
 187   return 0;
 188 }
 189
 190 void AsanCheckDynamicRTPrereqs() {}
 191
 192 void AsanCheckIncompatibleRT() {}
 193
 194 void ReadContextStack(void *context, uptr *stack, uptr *ssize) {
 195   UNIMPLEMENTED();
 196 }
 197
 198 void AsanOnDeadlySignal(int, void *siginfo, void *context) {
 199   UNIMPLEMENTED();
 200 }
 201
 202 static LPTOP_LEVEL_EXCEPTION_FILTER default_seh_handler;
 203
 204 static long WINAPI SEHHandler(EXCEPTION_POINTERS *info) {
 205   EXCEPTION_RECORD *exception_record = info->ExceptionRecord;
 206   CONTEXT *context = info->ContextRecord;
 207
 208   if (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION ||
 209       exception_record->ExceptionCode == EXCEPTION_IN_PAGE_ERROR) {
 210     const char *description =
 211         (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
 212             ? "access-violation"
 213             : "in-page-error";
 214     SignalContext sig = SignalContext::Create(exception_record, context);
 215     ReportDeadlySignal(description, sig);
 216   }
 217
 218   // FIXME: Handle EXCEPTION_STACK_OVERFLOW here.
 219
 220   return default_seh_handler(info);
 221 }
 222
 223 // We want to install our own exception handler (EH) to print helpful reports
 224 // on access violations and whatnot.  Unfortunately, the CRT initializers assume
 225 // they are run before any user code and drop any previously-installed EHs on
 226 // the floor, so we can't install our handler inside __asan_init.
 227 // (See crt0dat.c in the CRT sources for the details)
 228 //
 229 // Things get even more complicated with the dynamic runtime, as it finishes its
 230 // initialization before the .exe module CRT begins to initialize.
 231 //
 232 // For the static runtime (-MT), it's enough to put a callback to
 233 // __asan_set_seh_filter in the last section for C initializers.
 234 //
 235 // For the dynamic runtime (-MD), we want link the same
 236 // asan_dynamic_runtime_thunk.lib to all the modules, thus __asan_set_seh_filter
 237 // will be called for each instrumented module.  This ensures that at least one
 238 // __asan_set_seh_filter call happens after the .exe module CRT is initialized.
 239 extern "C" SANITIZER_INTERFACE_ATTRIBUTE
 240 int __asan_set_seh_filter() {
 241   // We should only store the previous handler if it's not our own handler in
 242   // order to avoid loops in the EH chain.
 243   auto prev_seh_handler = SetUnhandledExceptionFilter(SEHHandler);
 244   if (prev_seh_handler != &SEHHandler)
 245     default_seh_handler = prev_seh_handler;
 246   return 0;
 247 }
 248
 249 #if !ASAN_DYNAMIC
 250 // Put a pointer to __asan_set_seh_filter at the end of the global list
 251 // of C initializers, after the default EH is set by the CRT.
 252 #pragma section(".CRT$XIZ", long, read)  // NOLINT
 253 __declspec(allocate(".CRT$XIZ"))
 254     int (*__intercept_seh)() = __asan_set_seh_filter;
 255 #endif
 256 // }}}
 257 }  // namespace __asan
 258
 259 #endif  // _WIN32