[compiler-rt] r224823 - [ASan/Win] Bandaid fix for PR22025 -- deadlocks when creating suspended threads

[Timur Iskhodzhanov]

Author: timurrrr
Date: Wed Dec 24 10:14:16 2014
New Revision: 224823

URL: http://llvm.org/viewvc/llvm-project?rev=224823&view=rev
Log:
[ASan/Win] Bandaid fix for PR22025 -- deadlocks when creating suspended threads

Added:
    compiler-rt/trunk/test/asan/TestCases/Windows/thread_suspended.cc
Modified:
    compiler-rt/trunk/lib/asan/asan_interceptors.cc

Modified: compiler-rt/trunk/lib/asan/asan_interceptors.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_interceptors.cc?rev=224823&r1=224822&r2=224823&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_interceptors.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_interceptors.cc Wed Dec 24 10:14:16 2014
@@ -196,6 +196,12 @@ struct ThreadStartParam {
 };
 
 static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
+#if SANITIZER_WINDOWS
+  // FIXME: this is a bandaid fix for PR22025.
+  AsanThread *t = (AsanThread*)arg;
+  SetCurrentThread(t);
+  return t->ThreadStart(GetTid(), /* signal_thread_is_registered */ nullptr);
+#else
   ThreadStartParam *param = reinterpret_cast<ThreadStartParam *>(arg);
   AsanThread *t = nullptr;
   while ((t = reinterpret_cast<AsanThread *>(
@@ -203,6 +209,7 @@ static thread_return_t THREAD_CALLING_CO
     internal_sched_yield();
   SetCurrentThread(t);
   return t->ThreadStart(GetTid(), &param->is_registered);
+#endif
 }
 
 #if ASAN_INTERCEPT_PTHREAD_CREATE
@@ -807,23 +814,14 @@ INTERCEPTOR_WINAPI(DWORD, CreateThread,
   if (flags()->strict_init_order)
     StopInitOrderChecking();
   GET_STACK_TRACE_THREAD;
+  // FIXME: The CreateThread interceptor is not the same as a pthread_create
+  // one.  This is a bandaid fix for PR22025.
   bool detached = false;  // FIXME: how can we determine it on Windows?
-  ThreadStartParam param;
-  atomic_store(&param.t, 0, memory_order_relaxed);
-  atomic_store(&param.is_registered, 0, memory_order_relaxed);
-  DWORD result = REAL(CreateThread)(security, stack_size, asan_thread_start,
-                                    &param, thr_flags, tid);
-  if (result) {
-    u32 current_tid = GetCurrentTidOrInvalid();
-    AsanThread *t =
+  u32 current_tid = GetCurrentTidOrInvalid();
+  AsanThread *t =
         AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
-    atomic_store(&param.t, reinterpret_cast<uptr>(t), memory_order_release);
-    // The pthread_create interceptor waits here, so we do the same for
-    // consistency.
-    while (atomic_load(&param.is_registered, memory_order_acquire) == 0)
-      internal_sched_yield();
-  }
-  return result;
+  return REAL(CreateThread)(security, stack_size,
+                            asan_thread_start, t, thr_flags, tid);
 }
 
 namespace __asan {

Added: compiler-rt/trunk/test/asan/TestCases/Windows/thread_suspended.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/asan/TestCases/Windows/thread_suspended.cc?rev=224823&view=auto
==============================================================================
--- compiler-rt/trunk/test/asan/TestCases/Windows/thread_suspended.cc (added)
+++ compiler-rt/trunk/test/asan/TestCases/Windows/thread_suspended.cc Wed Dec 24 10:14:16 2014
@@ -0,0 +1,27 @@
+// RUN: %clang_cl_asan -O0 %s -Fe%t
+// RUN: %run %t
+
+#include <windows.h>
+
+DWORD WINAPI thread_proc(void *) {
+  volatile char stack_buffer[42];
+  for (int i = 0; i < sizeof(stack_buffer); ++i)
+    stack_buffer[i] = 42;
+  return 0x42;
+}
+
+int main() {
+  DWORD exitcode;
+  HANDLE thr = CreateThread(NULL, 0, thread_proc, NULL, CREATE_SUSPENDED, NULL);
+  ResumeThread(thr);
+  if (thr == 0)
+    return 1;
+  if (WAIT_OBJECT_0 != WaitForSingleObject(thr, INFINITE))
+    return 2;
+
+  GetExitCodeThread(thr, &exitcode);
+  if (exitcode != 0x42)
+    return 3;
+  CloseHandle(thr);
+}
+