1 files changed, 274 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/asan/asan_fuchsia.cpp b/contrib/llvm-project/compiler-rt/lib/asan/asan_fuchsia.cpp
new file mode 100644
index 000000000000..dbc4342e8338
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/asan/asan_fuchsia.cpp
@@ -0,0 +1,274 @@
+//===-- asan_fuchsia.cpp -------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===---------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// Fuchsia-specific details.
+//===---------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_fuchsia.h"
+#if SANITIZER_FUCHSIA
+
+#include <limits.h>
+#include <zircon/sanitizer.h>
+#include <zircon/syscalls.h>
+#include <zircon/threads.h>
+
+#  include "asan_interceptors.h"
+#  include "asan_internal.h"
+#  include "asan_stack.h"
+#  include "asan_thread.h"
+#  include "lsan/lsan_common.h"
+
+namespace __asan {
+
+// The system already set up the shadow memory for us.
+// __sanitizer::GetMaxUserVirtualAddress has already been called by
+// AsanInitInternal->InitializeHighMemEnd (asan_rtl.cpp).
+// Just do some additional sanity checks here.
+void InitializeShadowMemory() {
+  if (Verbosity())
+    PrintAddressSpaceLayout();
+
+  // Make sure SHADOW_OFFSET doesn't use __asan_shadow_memory_dynamic_address.
+  __asan_shadow_memory_dynamic_address = kDefaultShadowSentinel;
+  DCHECK(kLowShadowBeg != kDefaultShadowSentinel);
+  __asan_shadow_memory_dynamic_address = kLowShadowBeg;
+
+  CHECK_EQ(kShadowGapEnd, kHighShadowBeg - 1);
+  CHECK_EQ(kHighMemEnd, __sanitizer::ShadowBounds.memory_limit - 1);
+  CHECK_EQ(kHighMemBeg, __sanitizer::ShadowBounds.shadow_limit);
+  CHECK_EQ(kHighShadowBeg, __sanitizer::ShadowBounds.shadow_base);
+  CHECK_EQ(kShadowGapEnd, __sanitizer::ShadowBounds.shadow_base - 1);
+  CHECK_EQ(kLowShadowEnd, 0);
+  CHECK_EQ(kLowShadowBeg, 0);
+}
+
+void AsanApplyToGlobals(globals_op_fptr op, const void *needle) {
+  UNIMPLEMENTED();
+}
+
+void AsanCheckDynamicRTPrereqs() {}
+void AsanCheckIncompatibleRT() {}
+void InitializeAsanInterceptors() {}
+
+void InitializePlatformExceptionHandlers() {}
+void AsanOnDeadlySignal(int signo, void *siginfo, void *context) {
+  UNIMPLEMENTED();
+}
+
+bool PlatformUnpoisonStacks() {
+  // The current sp might not point to the default stack. This
+  // could be because we are in a crash stack from fuzzing for example.
+  // Unpoison the default stack and the current stack page.
+  AsanThread *curr_thread = GetCurrentThread();
+  CHECK(curr_thread != nullptr);
+  uptr top = curr_thread->stack_top();
+  uptr bottom = curr_thread->stack_bottom();
+  // The default stack grows from top to bottom. (bottom < top).
+
+  uptr local_stack = reinterpret_cast<uptr>(__builtin_frame_address(0));
+  if (local_stack >= bottom && local_stack <= top) {
+    // The current stack is the default stack.
+    // We only need to unpoison from where we are using until the end.
+    bottom = RoundDownTo(local_stack, GetPageSize());
+    UnpoisonStack(bottom, top, "default");
+  } else {
+    // The current stack is not the default stack.
+    // Unpoison the entire default stack and the current stack page.
+    UnpoisonStack(bottom, top, "default");
+    bottom = RoundDownTo(local_stack, GetPageSize());
+    top = bottom + GetPageSize();
+    UnpoisonStack(bottom, top, "unknown");
+    return true;
+  }
+
+  return false;
+}
+
+// We can use a plain thread_local variable for TSD.
+static thread_local void *per_thread;
+
+void *AsanTSDGet() { return per_thread; }
+
+void AsanTSDSet(void *tsd) { per_thread = tsd; }
+
+// There's no initialization needed, and the passed-in destructor
+// will never be called.  Instead, our own thread destruction hook
+// (below) will call AsanThread::TSDDtor directly.
+void AsanTSDInit(void (*destructor)(void *tsd)) {
+  DCHECK(destructor == &PlatformTSDDtor);
+}
+
+void PlatformTSDDtor(void *tsd) { UNREACHABLE(__func__); }
+
+static inline size_t AsanThreadMmapSize() {
+  return RoundUpTo(sizeof(AsanThread), _zx_system_get_page_size());
+}
+
+struct AsanThread::InitOptions {
+  uptr stack_bottom, stack_size;
+};
+
+// Shared setup between thread creation and startup for the initial thread.
+static AsanThread *CreateAsanThread(StackTrace *stack, u32 parent_tid,
+                                    bool detached, const char *name) {
+  // In lieu of AsanThread::Create.
+  AsanThread *thread = (AsanThread *)MmapOrDie(AsanThreadMmapSize(), __func__);
+
+  AsanThreadContext::CreateThreadContextArgs args = {thread, stack};
+  u32 tid = asanThreadRegistry().CreateThread(0, detached, parent_tid, &args);
+  asanThreadRegistry().SetThreadName(tid, name);
+
+  return thread;
+}
+
+// This gets the same arguments passed to Init by CreateAsanThread, above.
+// We're in the creator thread before the new thread is actually started,
+// but its stack address range is already known.  We don't bother tracking
+// the static TLS address range because the system itself already uses an
+// ASan-aware allocator for that.
+void AsanThread::SetThreadStackAndTls(const AsanThread::InitOptions *options) {
+  DCHECK_NE(GetCurrentThread(), this);
+  DCHECK_NE(GetCurrentThread(), nullptr);
+  CHECK_NE(options->stack_bottom, 0);
+  CHECK_NE(options->stack_size, 0);
+  stack_bottom_ = options->stack_bottom;
+  stack_top_ = options->stack_bottom + options->stack_size;
+}
+
+// Called by __asan::AsanInitInternal (asan_rtl.c).
+AsanThread *CreateMainThread() {
+  thrd_t self = thrd_current();
+  char name[ZX_MAX_NAME_LEN];
+  CHECK_NE(__sanitizer::MainThreadStackBase, 0);
+  CHECK_GT(__sanitizer::MainThreadStackSize, 0);
+  AsanThread *t = CreateAsanThread(
+      nullptr, 0, true,
+      _zx_object_get_property(thrd_get_zx_handle(self), ZX_PROP_NAME, name,
+                              sizeof(name)) == ZX_OK
+          ? name
+          : nullptr);
+  // We need to set the current thread before calling AsanThread::Init() below,
+  // since it reads the thread ID.
+  SetCurrentThread(t);
+  DCHECK_EQ(t->tid(), 0);
+
+  const AsanThread::InitOptions options = {__sanitizer::MainThreadStackBase,
+                                           __sanitizer::MainThreadStackSize};
+  t->Init(&options);
+
+  return t;
+}
+
+// This is called before each thread creation is attempted.  So, in
+// its first call, the calling thread is the initial and sole thread.
+static void *BeforeThreadCreateHook(uptr user_id, bool detached,
+                                    const char *name, uptr stack_bottom,
+                                    uptr stack_size) {
+  EnsureMainThreadIDIsCorrect();
+  // Strict init-order checking is thread-hostile.
+  if (flags()->strict_init_order)
+    StopInitOrderChecking();
+
+  GET_STACK_TRACE_THREAD;
+  u32 parent_tid = GetCurrentTidOrInvalid();
+
+  AsanThread *thread = CreateAsanThread(&stack, parent_tid, detached, name);
+
+  // On other systems, AsanThread::Init() is called from the new
+  // thread itself.  But on Fuchsia we already know the stack address
+  // range beforehand, so we can do most of the setup right now.
+  const AsanThread::InitOptions options = {stack_bottom, stack_size};
+  thread->Init(&options);
+  return thread;
+}
+
+// This is called after creating a new thread (in the creating thread),
+// with the pointer returned by BeforeThreadCreateHook (above).
+static void ThreadCreateHook(void *hook, bool aborted) {
+  AsanThread *thread = static_cast<AsanThread *>(hook);
+  if (!aborted) {
+    // The thread was created successfully.
+    // ThreadStartHook is already running in the new thread.
+  } else {
+    // The thread wasn't created after all.
+    // Clean up everything we set up in BeforeThreadCreateHook.
+    asanThreadRegistry().FinishThread(thread->tid());
+    UnmapOrDie(thread, AsanThreadMmapSize());
+  }
+}
+
+// This is called in the newly-created thread before it runs anything else,
+// with the pointer returned by BeforeThreadCreateHook (above).
+// cf. asan_interceptors.cpp:asan_thread_start
+static void ThreadStartHook(void *hook, uptr os_id) {
+  AsanThread *thread = static_cast<AsanThread *>(hook);
+  SetCurrentThread(thread);
+
+  // In lieu of AsanThread::ThreadStart.
+  asanThreadRegistry().StartThread(thread->tid(), os_id, ThreadType::Regular,
+                                   nullptr);
+}
+
+// Each thread runs this just before it exits,
+// with the pointer returned by BeforeThreadCreateHook (above).
+// All per-thread destructors have already been called.
+static void ThreadExitHook(void *hook, uptr os_id) {
+  AsanThread::TSDDtor(per_thread);
+}
+
+bool HandleDlopenInit() {
+  // Not supported on this platform.
+  static_assert(!SANITIZER_SUPPORTS_INIT_FOR_DLOPEN,
+                "Expected SANITIZER_SUPPORTS_INIT_FOR_DLOPEN to be false");
+  return false;
+}
+
+void FlushUnneededASanShadowMemory(uptr p, uptr size) {
+  __sanitizer_fill_shadow(p, size, 0, 0);
+}
+
+// On Fuchsia, leak detection is done by a special hook after atexit hooks.
+// So this doesn't install any atexit hook like on other platforms.
+void InstallAtExitCheckLeaks() {}
+
+void InstallAtForkHandler() {}
+
+}  // namespace __asan
+
+namespace __lsan {
+
+bool UseExitcodeOnLeak() { return __asan::flags()->halt_on_error; }
+
+}  // namespace __lsan
+
+// These are declared (in extern "C") by <zircon/sanitizer.h>.
+// The system runtime will call our definitions directly.
+
+void *__sanitizer_before_thread_create_hook(thrd_t thread, bool detached,
+                                            const char *name, void *stack_base,
+                                            size_t stack_size) {
+  return __asan::BeforeThreadCreateHook(
+      reinterpret_cast<uptr>(thread), detached, name,
+      reinterpret_cast<uptr>(stack_base), stack_size);
+}
+
+void __sanitizer_thread_create_hook(void *hook, thrd_t thread, int error) {
+  __asan::ThreadCreateHook(hook, error != thrd_success);
+}
+
+void __sanitizer_thread_start_hook(void *hook, thrd_t self) {
+  __asan::ThreadStartHook(hook, reinterpret_cast<uptr>(self));
+}
+
+void __sanitizer_thread_exit_hook(void *hook, thrd_t self) {
+  __asan::ThreadExitHook(hook, reinterpret_cast<uptr>(self));
+}
+
+#endif  // SANITIZER_FUCHSIA