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 #define WIN32_LEAN_AND_MEAN
  16 #include <windows.h>
  17
  18 #include <stdlib.h>
  19
  20 #include "asan_interceptors.h"
  21 #include "asan_internal.h"
  22 #include "asan_report.h"
  23 #include "asan_stack.h"
  24 #include "asan_thread.h"
  25 #include "sanitizer_common/sanitizer_libc.h"
  26 #include "sanitizer_common/sanitizer_mutex.h"
  27
  28 using namespace __asan;  // NOLINT
  29
  30 extern "C" {
  31 SANITIZER_INTERFACE_ATTRIBUTE
  32 int __asan_should_detect_stack_use_after_return() {
  33   __asan_init();
  34   return __asan_option_detect_stack_use_after_return;
  35 }
  36
  37 // -------------------- A workaround for the abscence of weak symbols ----- {{{
  38 // We don't have a direct equivalent of weak symbols when using MSVC, but we can
  39 // use the /alternatename directive to tell the linker to default a specific
  40 // symbol to a specific value, which works nicely for allocator hooks and
  41 // __asan_default_options().
  42 void __sanitizer_default_malloc_hook(void *ptr, uptr size) { }
  43 void __sanitizer_default_free_hook(void *ptr) { }
  44 const char* __asan_default_default_options() { return ""; }
  45 const char* __asan_default_default_suppressions() { return ""; }
  46 void __asan_default_on_error() {}
  47 #pragma comment(linker, "/alternatename:___sanitizer_malloc_hook=___sanitizer_default_malloc_hook")  // NOLINT
  48 #pragma comment(linker, "/alternatename:___sanitizer_free_hook=___sanitizer_default_free_hook")      // NOLINT
  49 #pragma comment(linker, "/alternatename:___asan_default_options=___asan_default_default_options")    // NOLINT
  50 #pragma comment(linker, "/alternatename:___asan_default_suppressions=___asan_default_default_suppressions")    // NOLINT
  51 #pragma comment(linker, "/alternatename:___asan_on_error=___asan_default_on_error")                  // NOLINT
  52 // }}}
  53 }  // extern "C"
  54
  55 // ---------------------- Windows-specific inteceptors ---------------- {{{
  56 INTERCEPTOR_WINAPI(void, RaiseException, void *a, void *b, void *c, void *d) {
  57   CHECK(REAL(RaiseException));
  58   __asan_handle_no_return();
  59   REAL(RaiseException)(a, b, c, d);
  60 }
  61
  62 INTERCEPTOR(int, _except_handler3, void *a, void *b, void *c, void *d) {
  63   CHECK(REAL(_except_handler3));
  64   __asan_handle_no_return();
  65   return REAL(_except_handler3)(a, b, c, d);
  66 }
  67
  68 #if ASAN_DYNAMIC
  69 // This handler is named differently in -MT and -MD CRTs.
  70 #define _except_handler4 _except_handler4_common
  71 #endif
  72 INTERCEPTOR(int, _except_handler4, void *a, void *b, void *c, void *d) {
  73   CHECK(REAL(_except_handler4));
  74   __asan_handle_no_return();
  75   return REAL(_except_handler4)(a, b, c, d);
  76 }
  77
  78 static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
  79   AsanThread *t = (AsanThread*)arg;
  80   SetCurrentThread(t);
  81   return t->ThreadStart(GetTid(), /* signal_thread_is_registered */ nullptr);
  82 }
  83
  84 INTERCEPTOR_WINAPI(DWORD, CreateThread,
  85                    void* security, uptr stack_size,
  86                    DWORD (__stdcall *start_routine)(void*), void* arg,
  87                    DWORD thr_flags, void* tid) {
  88   // Strict init-order checking is thread-hostile.
  89   if (flags()->strict_init_order)
  90     StopInitOrderChecking();
  91   GET_STACK_TRACE_THREAD;
  92   // FIXME: The CreateThread interceptor is not the same as a pthread_create
  93   // one.  This is a bandaid fix for PR22025.
  94   bool detached = false;  // FIXME: how can we determine it on Windows?
  95   u32 current_tid = GetCurrentTidOrInvalid();
  96   AsanThread *t =
  97         AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
  98   return REAL(CreateThread)(security, stack_size,
  99                             asan_thread_start, t, thr_flags, tid);
 100 }
 101
 102 namespace {
 103 BlockingMutex mu_for_thread_tracking(LINKER_INITIALIZED);
 104
 105 void EnsureWorkerThreadRegistered() {
 106   // FIXME: GetCurrentThread relies on TSD, which might not play well with
 107   // system thread pools.  We might want to use something like reference
 108   // counting to zero out GetCurrentThread() underlying storage when the last
 109   // work item finishes?  Or can we disable reclaiming of threads in the pool?
 110   BlockingMutexLock l(&mu_for_thread_tracking);
 111   if (__asan::GetCurrentThread())
 112     return;
 113
 114   AsanThread *t = AsanThread::Create(
 115       /* start_routine */ nullptr, /* arg */ nullptr,
 116       /* parent_tid */ -1, /* stack */ nullptr, /* detached */ true);
 117   t->Init();
 118   asanThreadRegistry().StartThread(t->tid(), 0, 0);
 119   SetCurrentThread(t);
 120 }
 121 }  // namespace
 122
 123 INTERCEPTOR_WINAPI(DWORD, NtWaitForWorkViaWorkerFactory, DWORD a, DWORD b) {
 124   // NtWaitForWorkViaWorkerFactory is called from system worker pool threads to
 125   // query work scheduled by BindIoCompletionCallback, QueueUserWorkItem, etc.
 126   // System worker pool threads are created at arbitraty point in time and
 127   // without using CreateThread, so we wrap NtWaitForWorkViaWorkerFactory
 128   // instead and don't register a specific parent_tid/stack.
 129   EnsureWorkerThreadRegistered();
 130   return REAL(NtWaitForWorkViaWorkerFactory)(a, b);
 131 }
 132
 133 // }}}
 134
 135 namespace __asan {
 136
 137 void InitializePlatformInterceptors() {
 138   ASAN_INTERCEPT_FUNC(CreateThread);
 139   ASAN_INTERCEPT_FUNC(RaiseException);
 140   ASAN_INTERCEPT_FUNC(_except_handler3);
 141   ASAN_INTERCEPT_FUNC(_except_handler4);
 142
 143   // NtWaitForWorkViaWorkerFactory is always linked dynamically.
 144   CHECK(::__interception::OverrideFunction(
 145       "NtWaitForWorkViaWorkerFactory",
 146       (uptr)WRAP(NtWaitForWorkViaWorkerFactory),
 147       (uptr *)&REAL(NtWaitForWorkViaWorkerFactory)));
 148 }
 149
 150 // ---------------------- TSD ---------------- {{{
 151 static bool tsd_key_inited = false;
 152
 153 static __declspec(thread) void *fake_tsd = 0;
 154
 155 void AsanTSDInit(void (*destructor)(void *tsd)) {
 156   // FIXME: we're ignoring the destructor for now.
 157   tsd_key_inited = true;
 158 }
 159
 160 void *AsanTSDGet() {
 161   CHECK(tsd_key_inited);
 162   return fake_tsd;
 163 }
 164
 165 void AsanTSDSet(void *tsd) {
 166   CHECK(tsd_key_inited);
 167   fake_tsd = tsd;
 168 }
 169
 170 void PlatformTSDDtor(void *tsd) {
 171   AsanThread::TSDDtor(tsd);
 172 }
 173 // }}}
 174
 175 // ---------------------- Various stuff ---------------- {{{
 176 void DisableReexec() {
 177   // No need to re-exec on Windows.
 178 }
 179
 180 void MaybeReexec() {
 181   // No need to re-exec on Windows.
 182 }
 183
 184 void *AsanDoesNotSupportStaticLinkage() {
 185 #if defined(_DEBUG)
 186 #error Please build the runtime with a non-debug CRT: /MD or /MT
 187 #endif
 188   return 0;
 189 }
 190
 191 void AsanCheckDynamicRTPrereqs() {}
 192
 193 void AsanCheckIncompatibleRT() {}
 194
 195 void ReadContextStack(void *context, uptr *stack, uptr *ssize) {
 196   UNIMPLEMENTED();
 197 }
 198
 199 void AsanOnDeadlySignal(int, void *siginfo, void *context) {
 200   UNIMPLEMENTED();
 201 }
 202
 203 static LPTOP_LEVEL_EXCEPTION_FILTER default_seh_handler;
 204
 205 static long WINAPI SEHHandler(EXCEPTION_POINTERS *info) {
 206   EXCEPTION_RECORD *exception_record = info->ExceptionRecord;
 207   CONTEXT *context = info->ContextRecord;
 208
 209   if (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION ||
 210       exception_record->ExceptionCode == EXCEPTION_IN_PAGE_ERROR) {
 211     const char *description =
 212         (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
 213             ? "access-violation"
 214             : "in-page-error";
 215     SignalContext sig = SignalContext::Create(exception_record, context);
 216     ReportDeadlySignal(description, sig);
 217   }
 218
 219   // FIXME: Handle EXCEPTION_STACK_OVERFLOW here.
 220
 221   return default_seh_handler(info);
 222 }
 223
 224 // We want to install our own exception handler (EH) to print helpful reports
 225 // on access violations and whatnot.  Unfortunately, the CRT initializers assume
 226 // they are run before any user code and drop any previously-installed EHs on
 227 // the floor, so we can't install our handler inside __asan_init.
 228 // (See crt0dat.c in the CRT sources for the details)
 229 //
 230 // Things get even more complicated with the dynamic runtime, as it finishes its
 231 // initialization before the .exe module CRT begins to initialize.
 232 //
 233 // For the static runtime (-MT), it's enough to put a callback to
 234 // __asan_set_seh_filter in the last section for C initializers.
 235 //
 236 // For the dynamic runtime (-MD), we want link the same
 237 // asan_dynamic_runtime_thunk.lib to all the modules, thus __asan_set_seh_filter
 238 // will be called for each instrumented module.  This ensures that at least one
 239 // __asan_set_seh_filter call happens after the .exe module CRT is initialized.
 240 extern "C" SANITIZER_INTERFACE_ATTRIBUTE
 241 int __asan_set_seh_filter() {
 242   // We should only store the previous handler if it's not our own handler in
 243   // order to avoid loops in the EH chain.
 244   auto prev_seh_handler = SetUnhandledExceptionFilter(SEHHandler);
 245   if (prev_seh_handler != &SEHHandler)
 246     default_seh_handler = prev_seh_handler;
 247   return 0;
 248 }
 249
 250 #if !ASAN_DYNAMIC
 251 // Put a pointer to __asan_set_seh_filter at the end of the global list
 252 // of C initializers, after the default EH is set by the CRT.
 253 #pragma section(".CRT$XIZ", long, read)  // NOLINT
 254 __declspec(allocate(".CRT$XIZ"))
 255     int (*__intercept_seh)() = __asan_set_seh_filter;
 256 #endif
 257 // }}}
 258 }  // namespace __asan
 259
 260 #endif  // _WIN32