1 files changed, 71 insertions, 0 deletions
diff --git a/lib/ubsan/ubsan_signals_standalone.cpp b/lib/ubsan/ubsan_signals_standalone.cpp
new file mode 100644
index 000000000000..2c91db8ca397
--- /dev/null
+++ b/lib/ubsan/ubsan_signals_standalone.cpp
@@ -0,0 +1,71 @@
+//=-- ubsan_signals_standalone.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
+//
+//===----------------------------------------------------------------------===//
+//
+// Installs signal handlers and related interceptors for UBSan standalone.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ubsan_platform.h"
+#include "sanitizer_common/sanitizer_platform.h"
+#if CAN_SANITIZE_UB
+#include "interception/interception.h"
+#include "sanitizer_common/sanitizer_stacktrace.h"
+#include "ubsan_diag.h"
+#include "ubsan_init.h"
+
+// Interception of signals breaks too many things on Android.
+// * It requires that ubsan is the first dependency of the main executable for
+// the interceptors to work correctly. This complicates deployment, as it
+// prevents us from enabling ubsan on random platform modules independently.
+// * For this to work with ART VM, ubsan signal handler has to be set after the
+// debuggerd handler, but before the ART handler.
+// * Interceptors don't work at all when ubsan runtime is loaded late, ex. when
+// it is part of an APK that does not use wrap.sh method.
+#if SANITIZER_FUCHSIA || SANITIZER_ANDROID
+
+namespace __ubsan {
+void InitializeDeadlySignals() {}
+}
+
+#else
+
+#define COMMON_INTERCEPT_FUNCTION(name) INTERCEPT_FUNCTION(name)
+#include "sanitizer_common/sanitizer_signal_interceptors.inc"
+
+// TODO(yln): Temporary workaround. Will be removed.
+void ubsan_GetStackTrace(BufferedStackTrace *stack, uptr max_depth,
+                         uptr pc, uptr bp, void *context, bool fast);
+
+namespace __ubsan {
+
+static void OnStackUnwind(const SignalContext &sig, const void *,
+                          BufferedStackTrace *stack) {
+  ubsan_GetStackTrace(stack, kStackTraceMax,
+                      StackTrace::GetNextInstructionPc(sig.pc), sig.bp,
+                      sig.context, common_flags()->fast_unwind_on_fatal);
+}
+
+static void UBsanOnDeadlySignal(int signo, void *siginfo, void *context) {
+  HandleDeadlySignal(siginfo, context, GetTid(), &OnStackUnwind, nullptr);
+}
+
+static bool is_initialized = false;
+
+void InitializeDeadlySignals() {
+  if (is_initialized)
+    return;
+  is_initialized = true;
+  InitializeSignalInterceptors();
+  InstallDeadlySignalHandlers(&UBsanOnDeadlySignal);
+}
+
+} // namespace __ubsan
+
+#endif
+
+#endif // CAN_SANITIZE_UB