1 files changed, 207 insertions, 38 deletions

diff --git a/libsanitizer/asan/asan_thread.cc b/libsanitizer/asan/asan_thread.cc
index 02f49dd59ef..1da714c6013 100644
--- a/libsanitizer/asan/asan_thread.cc
+++ b/libsanitizer/asan/asan_thread.cc
@@ -11,46 +11,82 @@
 //===----------------------------------------------------------------------===//
 #include "asan_allocator.h"
 #include "asan_interceptors.h"
+#include "asan_poisoning.h"
 #include "asan_stack.h"
 #include "asan_thread.h"
-#include "asan_thread_registry.h"
 #include "asan_mapping.h"
 #include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_placement_new.h"
+#include "lsan/lsan_common.h"
 
 namespace __asan {
 
-AsanThread::AsanThread(LinkerInitialized x)
-    : fake_stack_(x),
-      malloc_storage_(x),
-      stats_(x) { }
+// AsanThreadContext implementation.
 
-AsanThread *AsanThread::Create(u32 parent_tid, thread_callback_t start_routine,
-                               void *arg, StackTrace *stack) {
+void AsanThreadContext::OnCreated(void *arg) {
+  CreateThreadContextArgs *args = static_cast<CreateThreadContextArgs*>(arg);
+  if (args->stack) {
+    internal_memcpy(&stack, args->stack, sizeof(stack));
+  }
+  thread = args->thread;
+  thread->set_context(this);
+}
+
+void AsanThreadContext::OnFinished() {
+  // Drop the link to the AsanThread object.
+  thread = 0;
+}
+
+// MIPS requires aligned address
+static ALIGNED(16) char thread_registry_placeholder[sizeof(ThreadRegistry)];
+static ThreadRegistry *asan_thread_registry;
+
+static ThreadContextBase *GetAsanThreadContext(u32 tid) {
+  void *mem = MmapOrDie(sizeof(AsanThreadContext), "AsanThreadContext");
+  return new(mem) AsanThreadContext(tid);
+}
+
+ThreadRegistry &asanThreadRegistry() {
+  static bool initialized;
+  // Don't worry about thread_safety - this should be called when there is
+  // a single thread.
+  if (!initialized) {
+    // Never reuse ASan threads: we store pointer to AsanThreadContext
+    // in TSD and can't reliably tell when no more TSD destructors will
+    // be called. It would be wrong to reuse AsanThreadContext for another
+    // thread before all TSD destructors will be called for it.
+    asan_thread_registry = new(thread_registry_placeholder) ThreadRegistry(
+        GetAsanThreadContext, kMaxNumberOfThreads, kMaxNumberOfThreads);
+    initialized = true;
+  }
+  return *asan_thread_registry;
+}
+
+AsanThreadContext *GetThreadContextByTidLocked(u32 tid) {
+  return static_cast<AsanThreadContext *>(
+      asanThreadRegistry().GetThreadLocked(tid));
+}
+
+// AsanThread implementation.
+
+AsanThread *AsanThread::Create(thread_callback_t start_routine,
+                               void *arg) {
   uptr PageSize = GetPageSizeCached();
   uptr size = RoundUpTo(sizeof(AsanThread), PageSize);
   AsanThread *thread = (AsanThread*)MmapOrDie(size, __FUNCTION__);
   thread->start_routine_ = start_routine;
   thread->arg_ = arg;
-
-  const uptr kSummaryAllocSize = PageSize;
-  CHECK_LE(sizeof(AsanThreadSummary), kSummaryAllocSize);
-  AsanThreadSummary *summary =
-      (AsanThreadSummary*)MmapOrDie(PageSize, "AsanThreadSummary");
-  summary->Init(parent_tid, stack);
-  summary->set_thread(thread);
-  thread->set_summary(summary);
+  thread->context_ = 0;
 
   return thread;
 }
 
-void AsanThreadSummary::TSDDtor(void *tsd) {
-  AsanThreadSummary *summary = (AsanThreadSummary*)tsd;
-  if (flags()->verbosity >= 1) {
-    Report("T%d TSDDtor\n", summary->tid());
-  }
-  if (summary->thread()) {
-    summary->thread()->Destroy();
-  }
+void AsanThread::TSDDtor(void *tsd) {
+  AsanThreadContext *context = (AsanThreadContext*)tsd;
+  if (flags()->verbosity >= 1)
+    Report("T%d TSDDtor\n", context->tid);
+  if (context->thread)
+    context->thread->Destroy();
 }
 
 void AsanThread::Destroy() {
@@ -58,41 +94,68 @@ void AsanThread::Destroy() {
     Report("T%d exited\n", tid());
   }
 
-  asanThreadRegistry().UnregisterThread(this);
-  CHECK(summary()->thread() == 0);
+  asanThreadRegistry().FinishThread(tid());
+  FlushToDeadThreadStats(&stats_);
   // We also clear the shadow on thread destruction because
   // some code may still be executing in later TSD destructors
   // and we don't want it to have any poisoned stack.
-  ClearShadowForThreadStack();
-  fake_stack().Cleanup();
+  ClearShadowForThreadStackAndTLS();
+  DeleteFakeStack();
   uptr size = RoundUpTo(sizeof(AsanThread), GetPageSizeCached());
   UnmapOrDie(this, size);
 }
 
+// We want to create the FakeStack lazyly on the first use, but not eralier
+// than the stack size is known and the procedure has to be async-signal safe.
+FakeStack *AsanThread::AsyncSignalSafeLazyInitFakeStack() {
+  uptr stack_size = this->stack_size();
+  if (stack_size == 0)  // stack_size is not yet available, don't use FakeStack.
+    return 0;
+  uptr old_val = 0;
+  // fake_stack_ has 3 states:
+  // 0   -- not initialized
+  // 1   -- being initialized
+  // ptr -- initialized
+  // This CAS checks if the state was 0 and if so changes it to state 1,
+  // if that was successfull, it initilizes the pointer.
+  if (atomic_compare_exchange_strong(
+      reinterpret_cast<atomic_uintptr_t *>(&fake_stack_), &old_val, 1UL,
+      memory_order_relaxed)) {
+    uptr stack_size_log = Log2(RoundUpToPowerOfTwo(stack_size));
+    if (flags()->uar_stack_size_log)
+      stack_size_log = static_cast<uptr>(flags()->uar_stack_size_log);
+    fake_stack_ = FakeStack::Create(stack_size_log);
+    SetTLSFakeStack(fake_stack_);
+    return fake_stack_;
+  }
+  return 0;
+}
+
 void AsanThread::Init() {
-  SetThreadStackTopAndBottom();
+  SetThreadStackAndTls();
   CHECK(AddrIsInMem(stack_bottom_));
   CHECK(AddrIsInMem(stack_top_ - 1));
-  ClearShadowForThreadStack();
+  ClearShadowForThreadStackAndTLS();
   if (flags()->verbosity >= 1) {
     int local = 0;
     Report("T%d: stack [%p,%p) size 0x%zx; local=%p\n",
            tid(), (void*)stack_bottom_, (void*)stack_top_,
            stack_top_ - stack_bottom_, &local);
   }
-  fake_stack_.Init(stack_size());
+  fake_stack_ = 0;  // Will be initialized lazily if needed.
   AsanPlatformThreadInit();
 }
 
-thread_return_t AsanThread::ThreadStart() {
+thread_return_t AsanThread::ThreadStart(uptr os_id) {
   Init();
+  asanThreadRegistry().StartThread(tid(), os_id, 0);
   if (flags()->use_sigaltstack) SetAlternateSignalStack();
 
   if (!start_routine_) {
     // start_routine_ == 0 if we're on the main thread or on one of the
     // OS X libdispatch worker threads. But nobody is supposed to call
     // ThreadStart() for the worker threads.
-    CHECK(tid() == 0);
+    CHECK_EQ(tid(), 0);
     return 0;
   }
 
@@ -105,24 +168,33 @@ thread_return_t AsanThread::ThreadStart() {
   return res;
 }
 
-void AsanThread::SetThreadStackTopAndBottom() {
-  GetThreadStackTopAndBottom(tid() == 0, &stack_top_, &stack_bottom_);
+void AsanThread::SetThreadStackAndTls() {
+  uptr tls_size = 0;
+  GetThreadStackAndTls(tid() == 0, &stack_bottom_, &stack_size_, &tls_begin_,
+                       &tls_size);
+  stack_top_ = stack_bottom_ + stack_size_;
+  tls_end_ = tls_begin_ + tls_size;
+
   int local;
   CHECK(AddrIsInStack((uptr)&local));
 }
 
-void AsanThread::ClearShadowForThreadStack() {
+void AsanThread::ClearShadowForThreadStackAndTLS() {
   PoisonShadow(stack_bottom_, stack_top_ - stack_bottom_, 0);
+  if (tls_begin_ != tls_end_)
+    PoisonShadow(tls_begin_, tls_end_ - tls_begin_, 0);
 }
 
-const char *AsanThread::GetFrameNameByAddr(uptr addr, uptr *offset) {
+const char *AsanThread::GetFrameNameByAddr(uptr addr, uptr *offset,
+                                           uptr *frame_pc) {
   uptr bottom = 0;
   if (AddrIsInStack(addr)) {
     bottom = stack_bottom();
-  } else {
-    bottom = fake_stack().AddrIsInFakeStack(addr);
+  } else if (has_fake_stack()) {
+    bottom = fake_stack()->AddrIsInFakeStack(addr);
     CHECK(bottom);
     *offset = addr - bottom;
+    *frame_pc = ((uptr*)bottom)[2];
     return  (const char *)((uptr*)bottom)[1];
   }
   uptr aligned_addr = addr & ~(SANITIZER_WORDSIZE/8 - 1);  // align addr.
@@ -147,7 +219,104 @@ const char *AsanThread::GetFrameNameByAddr(uptr addr, uptr *offset) {
   uptr* ptr = (uptr*)SHADOW_TO_MEM((uptr)(shadow_ptr + 1));
   CHECK(ptr[0] == kCurrentStackFrameMagic);
   *offset = addr - (uptr)ptr;
+  *frame_pc = ptr[2];
   return (const char*)ptr[1];
 }
 
+static bool ThreadStackContainsAddress(ThreadContextBase *tctx_base,
+                                       void *addr) {
+  AsanThreadContext *tctx = static_cast<AsanThreadContext*>(tctx_base);
+  AsanThread *t = tctx->thread;
+  if (!t) return false;
+  if (t->AddrIsInStack((uptr)addr)) return true;
+  if (t->has_fake_stack() && t->fake_stack()->AddrIsInFakeStack((uptr)addr))
+    return true;
+  return false;
+}
+
+AsanThread *GetCurrentThread() {
+  AsanThreadContext *context =
+      reinterpret_cast<AsanThreadContext *>(AsanTSDGet());
+  if (!context) {
+    if (SANITIZER_ANDROID) {
+      // On Android, libc constructor is called _after_ asan_init, and cleans up
+      // TSD. Try to figure out if this is still the main thread by the stack
+      // address. We are not entirely sure that we have correct main thread
+      // limits, so only do this magic on Android, and only if the found thread
+      // is the main thread.
+      AsanThreadContext *tctx = GetThreadContextByTidLocked(0);
+      if (ThreadStackContainsAddress(tctx, &context)) {
+        SetCurrentThread(tctx->thread);
+        return tctx->thread;
+      }
+    }
+    return 0;
+  }
+  return context->thread;
+}
+
+void SetCurrentThread(AsanThread *t) {
+  CHECK(t->context());
+  if (flags()->verbosity >= 2) {
+    Report("SetCurrentThread: %p for thread %p\n",
+           t->context(), (void*)GetThreadSelf());
+  }
+  // Make sure we do not reset the current AsanThread.
+  CHECK_EQ(0, AsanTSDGet());
+  AsanTSDSet(t->context());
+  CHECK_EQ(t->context(), AsanTSDGet());
+}
+
+u32 GetCurrentTidOrInvalid() {
+  AsanThread *t = GetCurrentThread();
+  return t ? t->tid() : kInvalidTid;
+}
+
+AsanThread *FindThreadByStackAddress(uptr addr) {
+  asanThreadRegistry().CheckLocked();
+  AsanThreadContext *tctx = static_cast<AsanThreadContext *>(
+      asanThreadRegistry().FindThreadContextLocked(ThreadStackContainsAddress,
+                                                   (void *)addr));
+  return tctx ? tctx->thread : 0;
+}
+
+void EnsureMainThreadIDIsCorrect() {
+  AsanThreadContext *context =
+      reinterpret_cast<AsanThreadContext *>(AsanTSDGet());
+  if (context && (context->tid == 0))
+    context->os_id = GetTid();
+}
 }  // namespace __asan
+
+// --- Implementation of LSan-specific functions --- {{{1
+namespace __lsan {
+bool GetThreadRangesLocked(uptr os_id, uptr *stack_begin, uptr *stack_end,
+                           uptr *tls_begin, uptr *tls_end,
+                           uptr *cache_begin, uptr *cache_end) {
+  __asan::AsanThreadContext *context = static_cast<__asan::AsanThreadContext *>(
+      __asan::asanThreadRegistry().FindThreadContextByOsIDLocked(os_id));
+  if (!context) return false;
+  __asan::AsanThread *t = context->thread;
+  if (!t) return false;
+  *stack_begin = t->stack_bottom();
+  *stack_end = t->stack_top();
+  *tls_begin = t->tls_begin();
+  *tls_end = t->tls_end();
+  // ASan doesn't keep allocator caches in TLS, so these are unused.
+  *cache_begin = 0;
+  *cache_end = 0;
+  return true;
+}
+
+void LockThreadRegistry() {
+  __asan::asanThreadRegistry().Lock();
+}
+
+void UnlockThreadRegistry() {
+  __asan::asanThreadRegistry().Unlock();
+}
+
+void EnsureMainThreadIDIsCorrect() {
+  __asan::EnsureMainThreadIDIsCorrect();
+}
+}  // namespace __lsan