1 files changed, 162 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/gwp_asan/crash_handler.cpp b/contrib/llvm-project/compiler-rt/lib/gwp_asan/crash_handler.cpp
new file mode 100644
index 000000000000..555365c6e6f4
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/gwp_asan/crash_handler.cpp
@@ -0,0 +1,162 @@
+//===-- crash_handler.cpp ---------------------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "gwp_asan/common.h"
+#include "gwp_asan/stack_trace_compressor.h"
+
+#include <assert.h>
+#include <stdint.h>
+#include <string.h>
+
+using AllocationMetadata = gwp_asan::AllocationMetadata;
+using Error = gwp_asan::Error;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+bool __gwp_asan_error_is_mine(const gwp_asan::AllocatorState *State,
+                              uintptr_t ErrorPtr) {
+  assert(State && "State should not be nullptr.");
+  if (State->FailureType != Error::UNKNOWN && State->FailureAddress != 0)
+    return true;
+
+  return ErrorPtr < State->GuardedPagePoolEnd &&
+         State->GuardedPagePool <= ErrorPtr;
+}
+
+uintptr_t
+__gwp_asan_get_internal_crash_address(const gwp_asan::AllocatorState *State,
+                                      uintptr_t ErrorPtr) {
+  // There can be a race between internally- and externally-raised faults. The
+  // fault address from the signal handler is used to discriminate whether it's
+  // internally- or externally-raised, and the pool maintains a special page at
+  // the end of the GuardedPagePool specifically for the internally-raised
+  // faults.
+  if (ErrorPtr != State->internallyDetectedErrorFaultAddress())
+    return 0u;
+  return State->FailureAddress;
+}
+
+static const AllocationMetadata *
+addrToMetadata(const gwp_asan::AllocatorState *State,
+               const AllocationMetadata *Metadata, uintptr_t Ptr) {
+  // Note - Similar implementation in guarded_pool_allocator.cpp.
+  return &Metadata[State->getNearestSlot(Ptr)];
+}
+
+gwp_asan::Error
+__gwp_asan_diagnose_error(const gwp_asan::AllocatorState *State,
+                          const gwp_asan::AllocationMetadata *Metadata,
+                          uintptr_t ErrorPtr) {
+  if (!__gwp_asan_error_is_mine(State, ErrorPtr))
+    return Error::UNKNOWN;
+
+  if (State->FailureType != Error::UNKNOWN)
+    return State->FailureType;
+
+  // Check for use-after-free.
+  if (addrToMetadata(State, Metadata, ErrorPtr)->IsDeallocated)
+    return Error::USE_AFTER_FREE;
+
+  // Check for buffer-overflow. Because of allocation alignment or left/right
+  // page placement, we can have buffer-overflows that don't touch a guarded
+  // page, but these are not possible to detect unless it's also a
+  // use-after-free, which is handled above.
+  if (State->isGuardPage(ErrorPtr)) {
+    size_t Slot = State->getNearestSlot(ErrorPtr);
+    const AllocationMetadata *SlotMeta =
+        addrToMetadata(State, Metadata, State->slotToAddr(Slot));
+
+    // Ensure that this slot was allocated once upon a time.
+    if (!SlotMeta->Addr)
+      return Error::UNKNOWN;
+
+    if (SlotMeta->Addr < ErrorPtr)
+      return Error::BUFFER_OVERFLOW;
+    return Error::BUFFER_UNDERFLOW;
+  }
+
+  // If we have reached here, the error is still unknown.
+  return Error::UNKNOWN;
+}
+
+const gwp_asan::AllocationMetadata *
+__gwp_asan_get_metadata(const gwp_asan::AllocatorState *State,
+                        const gwp_asan::AllocationMetadata *Metadata,
+                        uintptr_t ErrorPtr) {
+  if (!__gwp_asan_error_is_mine(State, ErrorPtr))
+    return nullptr;
+
+  if (ErrorPtr >= State->GuardedPagePoolEnd ||
+      State->GuardedPagePool > ErrorPtr)
+    return nullptr;
+
+  const AllocationMetadata *Meta = addrToMetadata(State, Metadata, ErrorPtr);
+  if (Meta->Addr == 0)
+    return nullptr;
+
+  return Meta;
+}
+
+uintptr_t __gwp_asan_get_allocation_address(
+    const gwp_asan::AllocationMetadata *AllocationMeta) {
+  return AllocationMeta->Addr;
+}
+
+size_t __gwp_asan_get_allocation_size(
+    const gwp_asan::AllocationMetadata *AllocationMeta) {
+  return AllocationMeta->RequestedSize;
+}
+
+uint64_t __gwp_asan_get_allocation_thread_id(
+    const gwp_asan::AllocationMetadata *AllocationMeta) {
+  return AllocationMeta->AllocationTrace.ThreadID;
+}
+
+size_t __gwp_asan_get_allocation_trace(
+    const gwp_asan::AllocationMetadata *AllocationMeta, uintptr_t *Buffer,
+    size_t BufferLen) {
+  uintptr_t UncompressedBuffer[AllocationMetadata::kMaxTraceLengthToCollect];
+  size_t UnpackedLength = gwp_asan::compression::unpack(
+      AllocationMeta->AllocationTrace.CompressedTrace,
+      AllocationMeta->AllocationTrace.TraceSize, UncompressedBuffer,
+      AllocationMetadata::kMaxTraceLengthToCollect);
+  if (UnpackedLength < BufferLen)
+    BufferLen = UnpackedLength;
+  memcpy(Buffer, UncompressedBuffer, BufferLen * sizeof(*Buffer));
+  return UnpackedLength;
+}
+
+bool __gwp_asan_is_deallocated(
+    const gwp_asan::AllocationMetadata *AllocationMeta) {
+  return AllocationMeta->IsDeallocated;
+}
+
+uint64_t __gwp_asan_get_deallocation_thread_id(
+    const gwp_asan::AllocationMetadata *AllocationMeta) {
+  return AllocationMeta->DeallocationTrace.ThreadID;
+}
+
+size_t __gwp_asan_get_deallocation_trace(
+    const gwp_asan::AllocationMetadata *AllocationMeta, uintptr_t *Buffer,
+    size_t BufferLen) {
+  uintptr_t UncompressedBuffer[AllocationMetadata::kMaxTraceLengthToCollect];
+  size_t UnpackedLength = gwp_asan::compression::unpack(
+      AllocationMeta->DeallocationTrace.CompressedTrace,
+      AllocationMeta->DeallocationTrace.TraceSize, UncompressedBuffer,
+      AllocationMetadata::kMaxTraceLengthToCollect);
+  if (UnpackedLength < BufferLen)
+    BufferLen = UnpackedLength;
+  memcpy(Buffer, UncompressedBuffer, BufferLen * sizeof(*Buffer));
+  return UnpackedLength;
+}
+
+#ifdef __cplusplus
+} // extern "C"
+#endif