6 files changed, 115 insertions, 1 deletions
diff --git a/libunwindstack/Android.bp b/libunwindstack/Android.bp
index f0b4f2e..8fb5c3d 100644
--- a/libunwindstack/Android.bp
+++ b/libunwindstack/Android.bp
@@ -347,6 +347,7 @@ cc_defaults {
         "tests/MemoryCacheTest.cpp",
         "tests/MemoryFileTest.cpp",
         "tests/MemoryLocalTest.cpp",
+        "tests/MemoryLocalUnsafeTest.cpp",
         "tests/MemoryOfflineBufferTest.cpp",
         "tests/MemoryOfflineTest.cpp",
         "tests/MemoryRangeTest.cpp",
diff --git a/libunwindstack/Memory.cpp b/libunwindstack/Memory.cpp
index 258c54a..0594a7a 100644
--- a/libunwindstack/Memory.cpp
+++ b/libunwindstack/Memory.cpp
@@ -40,6 +40,7 @@
 #include "MemoryCache.h"
 #include "MemoryFileAtOffset.h"
 #include "MemoryLocal.h"
+#include "MemoryLocalUnsafe.h"
 #include "MemoryOffline.h"
 #include "MemoryOfflineBuffer.h"
 #include "MemoryRange.h"
@@ -201,6 +202,10 @@ std::shared_ptr<Memory> Memory::CreateFileMemory(const std::string& path, uint64
   return nullptr;
 }
 
+std::shared_ptr<Memory> Memory::CreateProcessMemoryLocalUnsafe() {
+  return std::shared_ptr<Memory>(new MemoryLocalUnsafe());
+}
+
 std::shared_ptr<Memory> Memory::CreateProcessMemory(pid_t pid) {
   if (pid == getpid()) {
     return std::shared_ptr<Memory>(new MemoryLocal());
@@ -581,4 +586,10 @@ void MemoryThreadCache::Clear() {
   }
 }
 
+size_t MemoryLocalUnsafe::Read(uint64_t addr, void* dst, size_t size) {
+  void* raw_ptr = reinterpret_cast<void*>(addr);
+  memcpy(dst, raw_ptr, size);
+  return size;
+}
+
 }  // namespace unwindstack
diff --git a/libunwindstack/MemoryLocalUnsafe.h b/libunwindstack/MemoryLocalUnsafe.h
new file mode 100644
index 0000000..130f025
--- /dev/null
+++ b/libunwindstack/MemoryLocalUnsafe.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+#include <unwindstack/Memory.h>
+
+namespace unwindstack {
+
+class MemoryLocalUnsafe : public Memory {
+ public:
+  MemoryLocalUnsafe() = default;
+  virtual ~MemoryLocalUnsafe() = default;
+
+  size_t Read(uint64_t addr, void* dst, size_t size) override;
+};
+
+}  // namespace unwindstack
diff --git a/libunwindstack/include/unwindstack/Memory.h b/libunwindstack/include/unwindstack/Memory.h
index 112fe19..ec95bb4 100644
--- a/libunwindstack/include/unwindstack/Memory.h
+++ b/libunwindstack/include/unwindstack/Memory.h
@@ -35,6 +35,10 @@ class Memory {
   static std::shared_ptr<Memory> CreateProcessMemory(pid_t pid);
   static std::shared_ptr<Memory> CreateProcessMemoryCached(pid_t pid);
   static std::shared_ptr<Memory> CreateProcessMemoryThreadCached(pid_t pid);
+  // This should only be used for performance. Using this could result
+  // in crashes if used to try and read stack data.
+  static std::shared_ptr<Memory> CreateProcessMemoryLocalUnsafe();
+
   static std::shared_ptr<Memory> CreateOfflineMemory(const uint8_t* data, uint64_t start,
                                                      uint64_t end);
   static std::shared_ptr<Memory> CreateFileMemory(const std::string& path, uint64_t offset,
diff --git a/libunwindstack/include/unwindstack/Unwinder.h b/libunwindstack/include/unwindstack/Unwinder.h
index d78da5c..91fd1d5 100644
--- a/libunwindstack/include/unwindstack/Unwinder.h
+++ b/libunwindstack/include/unwindstack/Unwinder.h
@@ -85,7 +85,7 @@ class Unwinder {
   static std::string FormatFrame(ArchEnum arch, const FrameData& frame,
                                  bool display_build_id = true);
 
-  void SetArch(ArchEnum arch) { arch_ = arch; };
+  void SetArch(ArchEnum arch) { arch_ = arch; }
 
   void SetJitDebug(JitDebug* jit_debug);
 
diff --git a/libunwindstack/tests/MemoryLocalUnsafeTest.cpp b/libunwindstack/tests/MemoryLocalUnsafeTest.cpp
new file mode 100644
index 0000000..fdd5614
--- /dev/null
+++ b/libunwindstack/tests/MemoryLocalUnsafeTest.cpp
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdint.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <vector>
+
+#include <gtest/gtest.h>
+
+#include "MemoryLocalUnsafe.h"
+
+namespace unwindstack {
+
+TEST(MemoryLocalUnsafeTest, read_smoke) {
+  std::vector<uint8_t> src(1024);
+  memset(src.data(), 0x4c, 1024);
+
+  auto local = Memory::CreateProcessMemoryLocalUnsafe();
+
+  std::vector<uint8_t> dst(1024);
+  ASSERT_TRUE(local->ReadFully(reinterpret_cast<uint64_t>(src.data()), dst.data(), 1024));
+  ASSERT_EQ(0, memcmp(src.data(), dst.data(), 1024));
+  for (size_t i = 0; i < 1024; i++) {
+    ASSERT_EQ(0x4cU, dst[i]);
+  }
+
+  memset(src.data(), 0x23, 512);
+  ASSERT_TRUE(local->ReadFully(reinterpret_cast<uint64_t>(src.data()), dst.data(), 1024));
+  ASSERT_EQ(0, memcmp(src.data(), dst.data(), 1024));
+  for (size_t i = 0; i < 512; i++) {
+    ASSERT_EQ(0x23U, dst[i]);
+  }
+  for (size_t i = 512; i < 1024; i++) {
+    ASSERT_EQ(0x4cU, dst[i]);
+  }
+}
+
+TEST(MemoryLocalUnsafeTest, read_crash) {
+  void* mapping =
+      mmap(nullptr, getpagesize(), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  ASSERT_NE(MAP_FAILED, mapping);
+
+  mprotect(mapping, getpagesize(), PROT_NONE);
+
+  auto local = Memory::CreateProcessMemoryLocalUnsafe();
+  std::vector<uint8_t> buffer(100);
+  ASSERT_DEATH(local->Read(reinterpret_cast<uint64_t>(mapping), buffer.data(), buffer.size()), "");
+}
+
+}  // namespace unwindstack