diff --git a/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.cpp b/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.cpp
index 548285a..9be9ea7 100644
--- a/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.cpp
+++ b/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.cpp
@@ -31,6 +31,14 @@
 GeneratorHub::GeneratorHub(const OnHalEvent& onHalEvent)
     : mOnHalEvent(onHalEvent), mThread(&GeneratorHub::run, this) {}
 
+GeneratorHub::~GeneratorHub() {
+    mShuttingDownFlag.store(true);
+    mCond.notify_all();
+    if (mThread.joinable()) {
+        mThread.join();
+    }
+}
+
 void GeneratorHub::registerGenerator(int32_t cookie, FakeValueGeneratorPtr generator) {
     {
         std::lock_guard<std::mutex> g(mLock);
@@ -58,15 +66,18 @@
 }
 
 void GeneratorHub::run() {
-    while (true) {
+    while (!mShuttingDownFlag.load()) {
         std::unique_lock<std::mutex> g(mLock);
         // Pop events whose generator does not exist (may be already unregistered)
         while (!mEventQueue.empty()
                && mGenerators.find(mEventQueue.top().cookie) == mGenerators.end()) {
              mEventQueue.pop();
         }
-        // Wait until event queue is not empty
-        mCond.wait(g, [this] { return !mEventQueue.empty(); });
+        // Wait until event queue is not empty or shutting down flag is set
+        mCond.wait(g, [this] { return !mEventQueue.empty() || mShuttingDownFlag.load(); });
+        if (mShuttingDownFlag.load()) {
+            break;
+        }
 
         const VhalEvent& curEvent = mEventQueue.top();
 
diff --git a/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.h b/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.h
index dcf6a4f..b25dbf1 100644
--- a/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.h
+++ b/automotive/vehicle/2.0/default/impl/vhal_v2_0/GeneratorHub.h
@@ -58,7 +58,7 @@
 
 public:
     GeneratorHub(const OnHalEvent& onHalEvent);
-    ~GeneratorHub() = default;
+    ~GeneratorHub();
 
     /**
      * Register a new generator. The generator will be discarded if it could not produce next event.
@@ -84,6 +84,7 @@
     mutable std::mutex mLock;
     std::condition_variable mCond;
     std::thread mThread;
+    std::atomic<bool> mShuttingDownFlag{false};
 };
 
 }  // namespace impl
diff --git a/camera/common/1.0/default/CameraModule.cpp b/camera/common/1.0/default/CameraModule.cpp
index 27e74f1..16fb85c 100644
--- a/camera/common/1.0/default/CameraModule.cpp
+++ b/camera/common/1.0/default/CameraModule.cpp
@@ -549,7 +549,6 @@
                 }
             }
         }
-        free_camera_metadata(metadata);
     }
 
     mCameraInfoMap.removeItem(cameraId);
diff --git a/drm/1.0/default/Android.bp b/drm/1.0/default/Android.bp
index af1c076..a5cba5c 100644
--- a/drm/1.0/default/Android.bp
+++ b/drm/1.0/default/Android.bp
@@ -32,6 +32,7 @@
         "-Werror",
         "-Wextra",
         "-Wall",
+        "-Wthread-safety",
     ],
     shared_libs: [
         "liblog",
@@ -42,7 +43,7 @@
     export_header_lib_headers: [
         "libutils_headers",
     ],
-    export_include_dirs : ["include"]
+    export_include_dirs: ["include"],
 }
 
 soong_config_module_type {
diff --git a/drm/1.0/default/CryptoPlugin.cpp b/drm/1.0/default/CryptoPlugin.cpp
index 2db3607..8dea7e9 100644
--- a/drm/1.0/default/CryptoPlugin.cpp
+++ b/drm/1.0/default/CryptoPlugin.cpp
@@ -53,6 +53,8 @@
             uint32_t bufferId) {
         sp<IMemory> hidlMemory = mapMemory(base);
 
+        std::lock_guard<std::mutex> shared_buffer_lock(mSharedBufferLock);
+
         // allow mapMemory to return nullptr
         mSharedBufferMap[bufferId] = hidlMemory;
         return Void();
@@ -65,7 +67,7 @@
             const SharedBuffer& source, uint64_t offset,
             const DestinationBuffer& destination,
             decrypt_cb _hidl_cb) {
-
+        std::unique_lock<std::mutex> shared_buffer_lock(mSharedBufferLock);
         if (mSharedBufferMap.find(source.bufferId) == mSharedBufferMap.end()) {
             _hidl_cb(Status::ERROR_DRM_CANNOT_HANDLE, 0, "source decrypt buffer base not set");
             return Void();
@@ -79,7 +81,7 @@
             }
         }
 
-        android::CryptoPlugin::Mode legacyMode;
+        android::CryptoPlugin::Mode legacyMode = android::CryptoPlugin::kMode_Unencrypted;
         switch(mode) {
         case Mode::UNENCRYPTED:
             legacyMode = android::CryptoPlugin::kMode_Unencrypted;
@@ -124,7 +126,11 @@
             return Void();
         }
 
-        if (source.offset + offset + source.size > sourceBase->getSize()) {
+        size_t totalSize = 0;
+        if (__builtin_add_overflow(source.offset, offset, &totalSize) ||
+            __builtin_add_overflow(totalSize, source.size, &totalSize) ||
+            totalSize > sourceBase->getSize()) {
+            android_errorWriteLog(0x534e4554, "176496160");
             _hidl_cb(Status::ERROR_DRM_CANNOT_HANDLE, 0, "invalid buffer size");
             return Void();
         }
@@ -142,7 +148,10 @@
                 return Void();
             }
 
-            if (destBuffer.offset + destBuffer.size > destBase->getSize()) {
+            size_t totalSize = 0;
+            if (__builtin_add_overflow(destBuffer.offset, destBuffer.size, &totalSize) ||
+                totalSize > destBase->getSize()) {
+                android_errorWriteLog(0x534e4554, "176496353");
                 _hidl_cb(Status::ERROR_DRM_CANNOT_HANDLE, 0, "invalid buffer size");
                 return Void();
             }
@@ -153,7 +162,7 @@
             }
 
             base = static_cast<uint8_t *>(static_cast<void *>(destBase->getPointer()));
-            destPtr = static_cast<void *>(base + destination.nonsecureMemory.offset);
+            destPtr = static_cast<void*>(base + destination.nonsecureMemory.offset);
         } else if (destination.type == BufferType::NATIVE_HANDLE) {
             if (!secure) {
                 _hidl_cb(Status::BAD_VALUE, 0, "native handle destination must be secure");
@@ -166,6 +175,10 @@
             _hidl_cb(Status::BAD_VALUE, 0, "invalid destination type");
             return Void();
         }
+
+        // release mSharedBufferLock
+        shared_buffer_lock.unlock();
+
         ssize_t result = mLegacyPlugin->decrypt(secure, keyId.data(), iv.data(),
                 legacyMode, legacyPattern, srcPtr, legacySubSamples.get(),
                 subSamples.size(), destPtr, &detailMessage);
diff --git a/drm/1.0/default/CryptoPlugin.h b/drm/1.0/default/CryptoPlugin.h
index 11cc2aa..0d091fa 100644
--- a/drm/1.0/default/CryptoPlugin.h
+++ b/drm/1.0/default/CryptoPlugin.h
@@ -17,11 +17,14 @@
 #ifndef ANDROID_HARDWARE_DRM_V1_0__CRYPTOPLUGIN_H
 #define ANDROID_HARDWARE_DRM_V1_0__CRYPTOPLUGIN_H
 
-#include <android/hidl/memory/1.0/IMemory.h>
+#include <android-base/thread_annotations.h>
 #include <android/hardware/drm/1.0/ICryptoPlugin.h>
+#include <android/hidl/memory/1.0/IMemory.h>
 #include <hidl/Status.h>
 #include <media/hardware/CryptoAPI.h>
 
+#include <mutex>
+
 namespace android {
 namespace hardware {
 namespace drm {
@@ -60,19 +63,21 @@
     Return<void> setSharedBufferBase(const ::android::hardware::hidl_memory& base,
         uint32_t bufferId) override;
 
-    Return<void> decrypt(bool secure, const hidl_array<uint8_t, 16>& keyId,
-            const hidl_array<uint8_t, 16>& iv, Mode mode, const Pattern& pattern,
-            const hidl_vec<SubSample>& subSamples, const SharedBuffer& source,
-            uint64_t offset, const DestinationBuffer& destination,
-            decrypt_cb _hidl_cb) override;
+    Return<void> decrypt(
+            bool secure, const hidl_array<uint8_t, 16>& keyId, const hidl_array<uint8_t, 16>& iv,
+            Mode mode, const Pattern& pattern, const hidl_vec<SubSample>& subSamples,
+            const SharedBuffer& source, uint64_t offset, const DestinationBuffer& destination,
+            decrypt_cb _hidl_cb) override NO_THREAD_SAFETY_ANALYSIS;  // use unique_lock
 
-private:
+  private:
     android::CryptoPlugin *mLegacyPlugin;
-    std::map<uint32_t, sp<IMemory> > mSharedBufferMap;
+    std::map<uint32_t, sp<IMemory>> mSharedBufferMap GUARDED_BY(mSharedBufferLock);
 
     CryptoPlugin() = delete;
     CryptoPlugin(const CryptoPlugin &) = delete;
     void operator=(const CryptoPlugin &) = delete;
+
+    std::mutex mSharedBufferLock;
 };
 
 }  // namespace implementation