1 //===-- asan_win.cc -------------------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of AddressSanitizer, an address sanity checker.
12 // Windows-specific details.
13 //===----------------------------------------------------------------------===//
15 #include "sanitizer_common/sanitizer_platform.h"
17 #define WIN32_LEAN_AND_MEAN
22 #include "asan_interceptors.h"
23 #include "asan_internal.h"
24 #include "asan_report.h"
25 #include "asan_stack.h"
26 #include "asan_thread.h"
27 #include "sanitizer_common/sanitizer_libc.h"
28 #include "sanitizer_common/sanitizer_mutex.h"
30 using namespace __asan; // NOLINT
33 SANITIZER_INTERFACE_ATTRIBUTE
34 int __asan_should_detect_stack_use_after_return() {
36 return __asan_option_detect_stack_use_after_return;
39 // -------------------- A workaround for the abscence of weak symbols ----- {{{
40 // We don't have a direct equivalent of weak symbols when using MSVC, but we can
41 // use the /alternatename directive to tell the linker to default a specific
42 // symbol to a specific value, which works nicely for allocator hooks and
43 // __asan_default_options().
44 void __sanitizer_default_malloc_hook(void *ptr, uptr size) { }
45 void __sanitizer_default_free_hook(void *ptr) { }
46 const char* __asan_default_default_options() { return ""; }
47 const char* __asan_default_default_suppressions() { return ""; }
48 void __asan_default_on_error() {}
49 #pragma comment(linker, "/alternatename:___sanitizer_malloc_hook=___sanitizer_default_malloc_hook") // NOLINT
50 #pragma comment(linker, "/alternatename:___sanitizer_free_hook=___sanitizer_default_free_hook") // NOLINT
51 #pragma comment(linker, "/alternatename:___asan_default_options=___asan_default_default_options") // NOLINT
52 #pragma comment(linker, "/alternatename:___asan_default_suppressions=___asan_default_default_suppressions") // NOLINT
53 #pragma comment(linker, "/alternatename:___asan_on_error=___asan_default_on_error") // NOLINT
57 // ---------------------- Windows-specific inteceptors ---------------- {{{
58 INTERCEPTOR_WINAPI(void, RaiseException, void *a, void *b, void *c, void *d) {
59 CHECK(REAL(RaiseException));
60 __asan_handle_no_return();
61 REAL(RaiseException)(a, b, c, d);
64 INTERCEPTOR(int, _except_handler3, void *a, void *b, void *c, void *d) {
65 CHECK(REAL(_except_handler3));
66 __asan_handle_no_return();
67 return REAL(_except_handler3)(a, b, c, d);
71 // This handler is named differently in -MT and -MD CRTs.
72 #define _except_handler4 _except_handler4_common
74 INTERCEPTOR(int, _except_handler4, void *a, void *b, void *c, void *d) {
75 CHECK(REAL(_except_handler4));
76 __asan_handle_no_return();
77 return REAL(_except_handler4)(a, b, c, d);
80 static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
81 AsanThread *t = (AsanThread*)arg;
83 return t->ThreadStart(GetTid(), /* signal_thread_is_registered */ nullptr);
86 INTERCEPTOR_WINAPI(DWORD, CreateThread,
87 void* security, uptr stack_size,
88 DWORD (__stdcall *start_routine)(void*), void* arg,
89 DWORD thr_flags, void* tid) {
90 // Strict init-order checking is thread-hostile.
91 if (flags()->strict_init_order)
92 StopInitOrderChecking();
93 GET_STACK_TRACE_THREAD;
94 // FIXME: The CreateThread interceptor is not the same as a pthread_create
95 // one. This is a bandaid fix for PR22025.
96 bool detached = false; // FIXME: how can we determine it on Windows?
97 u32 current_tid = GetCurrentTidOrInvalid();
99 AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
100 return REAL(CreateThread)(security, stack_size,
101 asan_thread_start, t, thr_flags, tid);
105 BlockingMutex mu_for_thread_tracking(LINKER_INITIALIZED);
107 void EnsureWorkerThreadRegistered() {
108 // FIXME: GetCurrentThread relies on TSD, which might not play well with
109 // system thread pools. We might want to use something like reference
110 // counting to zero out GetCurrentThread() underlying storage when the last
111 // work item finishes? Or can we disable reclaiming of threads in the pool?
112 BlockingMutexLock l(&mu_for_thread_tracking);
113 if (__asan::GetCurrentThread())
116 AsanThread *t = AsanThread::Create(
117 /* start_routine */ nullptr, /* arg */ nullptr,
118 /* parent_tid */ -1, /* stack */ nullptr, /* detached */ true);
120 asanThreadRegistry().StartThread(t->tid(), 0, 0);
125 INTERCEPTOR_WINAPI(DWORD, NtWaitForWorkViaWorkerFactory, DWORD a, DWORD b) {
126 // NtWaitForWorkViaWorkerFactory is called from system worker pool threads to
127 // query work scheduled by BindIoCompletionCallback, QueueUserWorkItem, etc.
128 // System worker pool threads are created at arbitraty point in time and
129 // without using CreateThread, so we wrap NtWaitForWorkViaWorkerFactory
130 // instead and don't register a specific parent_tid/stack.
131 EnsureWorkerThreadRegistered();
132 return REAL(NtWaitForWorkViaWorkerFactory)(a, b);
139 void InitializePlatformInterceptors() {
140 ASAN_INTERCEPT_FUNC(CreateThread);
141 ASAN_INTERCEPT_FUNC(RaiseException);
142 ASAN_INTERCEPT_FUNC(_except_handler3);
143 ASAN_INTERCEPT_FUNC(_except_handler4);
145 // NtWaitForWorkViaWorkerFactory is always linked dynamically.
146 CHECK(::__interception::OverrideFunction(
147 "NtWaitForWorkViaWorkerFactory",
148 (uptr)WRAP(NtWaitForWorkViaWorkerFactory),
149 (uptr *)&REAL(NtWaitForWorkViaWorkerFactory)));
152 // ---------------------- TSD ---------------- {{{
153 static bool tsd_key_inited = false;
155 static __declspec(thread) void *fake_tsd = 0;
157 void AsanTSDInit(void (*destructor)(void *tsd)) {
158 // FIXME: we're ignoring the destructor for now.
159 tsd_key_inited = true;
163 CHECK(tsd_key_inited);
167 void AsanTSDSet(void *tsd) {
168 CHECK(tsd_key_inited);
172 void PlatformTSDDtor(void *tsd) {
173 AsanThread::TSDDtor(tsd);
177 // ---------------------- Various stuff ---------------- {{{
178 void *AsanDoesNotSupportStaticLinkage() {
180 #error Please build the runtime with a non-debug CRT: /MD or /MT
185 void AsanCheckDynamicRTPrereqs() {}
187 void AsanCheckIncompatibleRT() {}
189 void ReadContextStack(void *context, uptr *stack, uptr *ssize) {
193 void AsanOnDeadlySignal(int, void *siginfo, void *context) {
197 static LPTOP_LEVEL_EXCEPTION_FILTER default_seh_handler;
199 static long WINAPI SEHHandler(EXCEPTION_POINTERS *info) {
200 EXCEPTION_RECORD *exception_record = info->ExceptionRecord;
201 CONTEXT *context = info->ContextRecord;
203 if (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION ||
204 exception_record->ExceptionCode == EXCEPTION_IN_PAGE_ERROR) {
205 const char *description =
206 (exception_record->ExceptionCode == EXCEPTION_ACCESS_VIOLATION)
209 SignalContext sig = SignalContext::Create(exception_record, context);
210 ReportDeadlySignal(description, sig);
213 // FIXME: Handle EXCEPTION_STACK_OVERFLOW here.
215 return default_seh_handler(info);
218 // We want to install our own exception handler (EH) to print helpful reports
219 // on access violations and whatnot. Unfortunately, the CRT initializers assume
220 // they are run before any user code and drop any previously-installed EHs on
221 // the floor, so we can't install our handler inside __asan_init.
222 // (See crt0dat.c in the CRT sources for the details)
224 // Things get even more complicated with the dynamic runtime, as it finishes its
225 // initialization before the .exe module CRT begins to initialize.
227 // For the static runtime (-MT), it's enough to put a callback to
228 // __asan_set_seh_filter in the last section for C initializers.
230 // For the dynamic runtime (-MD), we want link the same
231 // asan_dynamic_runtime_thunk.lib to all the modules, thus __asan_set_seh_filter
232 // will be called for each instrumented module. This ensures that at least one
233 // __asan_set_seh_filter call happens after the .exe module CRT is initialized.
234 extern "C" SANITIZER_INTERFACE_ATTRIBUTE
235 int __asan_set_seh_filter() {
236 // We should only store the previous handler if it's not our own handler in
237 // order to avoid loops in the EH chain.
238 auto prev_seh_handler = SetUnhandledExceptionFilter(SEHHandler);
239 if (prev_seh_handler != &SEHHandler)
240 default_seh_handler = prev_seh_handler;
245 // Put a pointer to __asan_set_seh_filter at the end of the global list
246 // of C initializers, after the default EH is set by the CRT.
247 #pragma section(".CRT$XIZ", long, read) // NOLINT
248 __declspec(allocate(".CRT$XIZ"))
249 int (*__intercept_seh)() = __asan_set_seh_filter;
252 } // namespace __asan