Merge "Fix possible uaf of play policy state" into qt-dev
diff --git a/drm/mediadrm/plugins/clearkey/hidl/Android.bp b/drm/mediadrm/plugins/clearkey/hidl/Android.bp
index e91e918..fdb18d0 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/Android.bp
+++ b/drm/mediadrm/plugins/clearkey/hidl/Android.bp
@@ -37,7 +37,7 @@
 
     relative_install_path: "hw",
 
-    cflags: ["-Wall", "-Werror"],
+    cflags: ["-Wall", "-Werror", "-Wthread-safety"],
 
     shared_libs: [
         "android.hardware.drm@1.0",
diff --git a/drm/mediadrm/plugins/clearkey/hidl/CryptoPlugin.cpp b/drm/mediadrm/plugins/clearkey/hidl/CryptoPlugin.cpp
index d278633..005e551 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/CryptoPlugin.cpp
+++ b/drm/mediadrm/plugins/clearkey/hidl/CryptoPlugin.cpp
@@ -142,12 +142,14 @@
 
     base = static_cast<uint8_t *>(static_cast<void *>(destBase->getPointer()));
 
-    if (destBuffer.offset + destBuffer.size > destBase->getSize()) {
+    totalSize = 0;
+    if (__builtin_add_overflow(destBuffer.offset, destBuffer.size, &totalSize) ||
+        totalSize > destBase->getSize()) {
+        android_errorWriteLog(0x534e4554, "176444622");
         _hidl_cb(Status_V1_2::ERROR_DRM_FRAME_TOO_LARGE, 0, "invalid buffer size");
         return Void();
     }
-    destPtr = static_cast<void *>(base + destination.nonsecureMemory.offset);
-
+    destPtr = static_cast<void*>(base + destination.nonsecureMemory.offset);
 
     // Calculate the output buffer size and determine if any subsamples are
     // encrypted.
diff --git a/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp b/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
index 1ae4078..f33b648 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
+++ b/drm/mediadrm/plugins/clearkey/hidl/DrmPlugin.cpp
@@ -213,6 +213,7 @@
         if (requestString.find(kOfflineLicense) != std::string::npos) {
             std::string emptyResponse;
             std::string keySetIdString(keySetId.begin(), keySetId.end());
+            Mutex::Autolock lock(mFileHandleLock);
             if (!mFileHandle.StoreLicense(keySetIdString,
                     DeviceFiles::kLicenseStateReleasing,
                     emptyResponse)) {
@@ -328,6 +329,7 @@
         }
         *keySetId = kKeySetIdPrefix + ByteArrayToHexString(
                 reinterpret_cast<const uint8_t*>(randomData.data()), randomData.size());
+        Mutex::Autolock lock(mFileHandleLock);
         if (mFileHandle.LicenseExists(*keySetId)) {
             // collision, regenerate
             ALOGV("Retry generating KeySetId");
@@ -380,6 +382,7 @@
     if (status == Status::OK) {
         if (isOfflineLicense) {
             if (isRelease) {
+                Mutex::Autolock lock(mFileHandleLock);
                 mFileHandle.DeleteLicense(keySetId);
             } else {
                 if (!makeKeySetId(&keySetId)) {
@@ -387,6 +390,7 @@
                     return Void();
                 }
 
+                Mutex::Autolock lock(mFileHandleLock);
                 bool ok = mFileHandle.StoreLicense(
                         keySetId,
                         DeviceFiles::kLicenseStateActive,
@@ -441,6 +445,7 @@
         DeviceFiles::LicenseState licenseState;
         std::string offlineLicense;
         Status status = Status::OK;
+        Mutex::Autolock lock(mFileHandleLock);
         if (!mFileHandle.RetrieveLicense(std::string(keySetId.begin(), keySetId.end()),
                 &licenseState, &offlineLicense)) {
             ALOGE("Failed to restore offline license");
@@ -692,6 +697,7 @@
 }
 
 Return<void> DrmPlugin::getOfflineLicenseKeySetIds(getOfflineLicenseKeySetIds_cb _hidl_cb) {
+    Mutex::Autolock lock(mFileHandleLock);
     std::vector<std::string> licenseNames = mFileHandle.ListLicenses();
     std::vector<KeySetId> keySetIds;
     if (mMockError != Status_V1_2::OK) {
@@ -712,6 +718,7 @@
         return toStatus_1_0(mMockError);
     }
     std::string licenseName(keySetId.begin(), keySetId.end());
+    Mutex::Autolock lock(mFileHandleLock);
     if (mFileHandle.DeleteLicense(licenseName)) {
         return Status::OK;
     }
@@ -720,6 +727,8 @@
 
 Return<void> DrmPlugin::getOfflineLicenseState(const KeySetId& keySetId,
         getOfflineLicenseState_cb _hidl_cb) {
+    Mutex::Autolock lock(mFileHandleLock);
+
     std::string licenseName(keySetId.begin(), keySetId.end());
     DeviceFiles::LicenseState state;
     std::string license;
diff --git a/drm/mediadrm/plugins/clearkey/hidl/MemoryFileSystem.cpp b/drm/mediadrm/plugins/clearkey/hidl/MemoryFileSystem.cpp
index 2dcd00f..d29acac 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/MemoryFileSystem.cpp
+++ b/drm/mediadrm/plugins/clearkey/hidl/MemoryFileSystem.cpp
@@ -24,11 +24,13 @@
 }
 
 bool MemoryFileSystem::FileExists(const std::string& fileName) const {
+    std::lock_guard<std::mutex> lock(mMemoryFileSystemLock);
     auto result = mMemoryFileSystem.find(fileName);
     return result != mMemoryFileSystem.end();
 }
 
 ssize_t MemoryFileSystem::GetFileSize(const std::string& fileName) const {
+    std::lock_guard<std::mutex> lock(mMemoryFileSystemLock);
     auto result = mMemoryFileSystem.find(fileName);
     if (result != mMemoryFileSystem.end()) {
         return static_cast<ssize_t>(result->second.getFileSize());
@@ -40,6 +42,7 @@
 
 std::vector<std::string> MemoryFileSystem::ListFiles() const {
     std::vector<std::string> list;
+    std::lock_guard<std::mutex> lock(mMemoryFileSystemLock);
     for (const auto& filename : mMemoryFileSystem) {
         list.push_back(filename.first);
     }
@@ -48,6 +51,7 @@
 
 size_t MemoryFileSystem::Read(const std::string& path, std::string* buffer) {
     std::string key = GetFileName(path);
+    std::lock_guard<std::mutex> lock(mMemoryFileSystemLock);
     auto result = mMemoryFileSystem.find(key);
     if (result != mMemoryFileSystem.end()) {
         std::string serializedHashFile = result->second.getContent();
@@ -61,6 +65,7 @@
 
 size_t MemoryFileSystem::Write(const std::string& path, const MemoryFile& memoryFile) {
     std::string key = GetFileName(path);
+    std::lock_guard<std::mutex> lock(mMemoryFileSystemLock);
     auto result = mMemoryFileSystem.find(key);
     if (result != mMemoryFileSystem.end()) {
         mMemoryFileSystem.erase(key);
@@ -70,6 +75,7 @@
 }
 
 bool MemoryFileSystem::RemoveFile(const std::string& fileName) {
+    std::lock_guard<std::mutex> lock(mMemoryFileSystemLock);
     auto result = mMemoryFileSystem.find(fileName);
     if (result != mMemoryFileSystem.end()) {
         mMemoryFileSystem.erase(result);
@@ -81,6 +87,7 @@
 }
 
 bool MemoryFileSystem::RemoveAllFiles() {
+    std::lock_guard<std::mutex> lock(mMemoryFileSystemLock);
     mMemoryFileSystem.clear();
     return mMemoryFileSystem.empty();
 }
diff --git a/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h b/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h
index 526f019..7ea58e0 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h
+++ b/drm/mediadrm/plugins/clearkey/hidl/include/DrmPlugin.h
@@ -416,7 +416,8 @@
         mMockError = Status_V1_2::OK;
     }
 
-    DeviceFiles mFileHandle;
+    Mutex mFileHandleLock;
+    DeviceFiles mFileHandle GUARDED_BY(mFileHandleLock);
 
     CLEARKEY_DISALLOW_COPY_AND_ASSIGN_AND_NEW(DrmPlugin);
 };
diff --git a/drm/mediadrm/plugins/clearkey/hidl/include/MemoryFileSystem.h b/drm/mediadrm/plugins/clearkey/hidl/include/MemoryFileSystem.h
index bcd9fd6..6ac0e2c 100644
--- a/drm/mediadrm/plugins/clearkey/hidl/include/MemoryFileSystem.h
+++ b/drm/mediadrm/plugins/clearkey/hidl/include/MemoryFileSystem.h
@@ -5,7 +5,9 @@
 #ifndef CLEARKEY_MEMORY_FILE_SYSTEM_H_
 #define CLEARKEY_MEMORY_FILE_SYSTEM_H_
 
+#include <android-base/thread_annotations.h>
 #include <map>
+#include <mutex>
 #include <string>
 
 #include "ClearKeyTypes.h"
@@ -49,10 +51,12 @@
     size_t Write(const std::string& pathName, const MemoryFile& memoryFile);
 
  private:
+    mutable std::mutex mMemoryFileSystemLock;
+
     // License file name is made up of a unique keySetId, therefore,
     // the filename can be used as the key to locate licenses in the
     // memory file system.
-    std::map<std::string, MemoryFile> mMemoryFileSystem;
+    std::map<std::string, MemoryFile> mMemoryFileSystem GUARDED_BY(mMemoryFileSystemLock);
 
     std::string GetFileName(const std::string& path);
 
diff --git a/media/libmedia/IMediaPlayer.cpp b/media/libmedia/IMediaPlayer.cpp
index ea06665..ba1c833 100644
--- a/media/libmedia/IMediaPlayer.cpp
+++ b/media/libmedia/IMediaPlayer.cpp
@@ -17,8 +17,8 @@
 
 #include <arpa/inet.h>
 #include <stdint.h>
-#include <sys/types.h>
 
+#include <binder/IPCThreadState.h>
 #include <binder/Parcel.h>
 
 #include <media/AudioResamplerPublic.h>
@@ -85,10 +85,36 @@
 };
 
 // ModDrm helpers
-static void readVector(const Parcel& reply, Vector<uint8_t>& vector) {
-    uint32_t size = reply.readUint32();
-    vector.insertAt((size_t)0, size);
-    reply.read(vector.editArray(), size);
+static status_t readVector(const Parcel& reply, Vector<uint8_t>& vector) {
+    uint32_t size = 0;
+    status_t status = reply.readUint32(&size);
+    if (status == OK) {
+        status = size <= reply.dataAvail() ? OK : BAD_VALUE;
+    }
+    if (status == OK) {
+        status = vector.insertAt((size_t) 0, size) >= 0 ? OK : NO_MEMORY;
+    }
+    if (status == OK) {
+        status = reply.read(vector.editArray(), size);
+    }
+    if (status != OK) {
+        char errorMsg[100];
+        char buganizerId[] = "173720767";
+        snprintf(errorMsg,
+                sizeof(errorMsg),
+                "%s: failed to read array. Size: %d, status: %d.",
+                __func__,
+                size,
+                status);
+        android_errorWriteWithInfoLog(
+                /* safetyNet tag= */ 0x534e4554,
+                buganizerId,
+                IPCThreadState::self()->getCallingUid(),
+                errorMsg,
+                strlen(errorMsg));
+        ALOGE("%s (b/%s)", errorMsg, buganizerId);
+    }
+    return status;
 }
 
 static void writeVector(Parcel& data, Vector<uint8_t> const& vector) {
@@ -964,8 +990,10 @@
             uint8_t uuid[16];
             data.read(uuid, sizeof(uuid));
             Vector<uint8_t> drmSessionId;
-            readVector(data, drmSessionId);
-
+            status_t status = readVector(data, drmSessionId);
+            if (status != OK) {
+              return status;
+            }
             uint32_t result = prepareDrm(uuid, drmSessionId);
             reply->writeInt32(result);
             return OK;
diff --git a/services/oboeservice/AAudioService.cpp b/services/oboeservice/AAudioService.cpp
index e6a8375..86e26a9 100644
--- a/services/oboeservice/AAudioService.cpp
+++ b/services/oboeservice/AAudioService.cpp
@@ -23,7 +23,6 @@
 #include <sstream>
 
 #include <aaudio/AAudio.h>
-#include <mediautils/SchedulingPolicyService.h>
 #include <mediautils/ServiceUtilities.h>
 #include <utils/String16.h>
 
@@ -144,28 +143,6 @@
     }
 }
 
-// If a close request is pending then close the stream
-bool AAudioService::releaseStream(const sp<AAudioServiceStreamBase> &serviceStream) {
-    bool closed = false;
-    // decrementAndRemoveStreamByHandle() uses a lock so that if there are two simultaneous closes
-    // then only one will get the pointer and do the close.
-    sp<AAudioServiceStreamBase> foundStream = mStreamTracker.decrementAndRemoveStreamByHandle(
-            serviceStream->getHandle());
-    if (foundStream.get() != nullptr) {
-        foundStream->close();
-        pid_t pid = foundStream->getOwnerProcessId();
-        AAudioClientTracker::getInstance().unregisterClientStream(pid, foundStream);
-        closed = true;
-    }
-    return closed;
-}
-
-aaudio_result_t AAudioService::checkForPendingClose(
-        const sp<AAudioServiceStreamBase> &serviceStream,
-        aaudio_result_t defaultResult) {
-    return releaseStream(serviceStream) ? AAUDIO_ERROR_INVALID_STATE : defaultResult;
-}
-
 aaudio_result_t AAudioService::closeStream(aaudio_handle_t streamHandle) {
     // Check permission and ownership first.
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
@@ -174,17 +151,20 @@
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
 
+    // This is protected by a lock in AAudioClientTracker.
+    // It is safe to unregister the same stream twice.
     pid_t pid = serviceStream->getOwnerProcessId();
     AAudioClientTracker::getInstance().unregisterClientStream(pid, serviceStream);
+    // This is protected by a lock in mStreamTracker.
+    // It is safe to remove the same stream twice.
+    mStreamTracker.removeStreamByHandle(streamHandle);
 
-    serviceStream->markCloseNeeded();
-    (void) releaseStream(serviceStream);
-    return AAUDIO_OK;
+    return serviceStream->close();
 }
 
 sp<AAudioServiceStreamBase> AAudioService::convertHandleToServiceStream(
         aaudio_handle_t streamHandle) {
-    sp<AAudioServiceStreamBase> serviceStream = mStreamTracker.getStreamByHandleAndIncrement(
+    sp<AAudioServiceStreamBase> serviceStream = mStreamTracker.getStreamByHandle(
             streamHandle);
     if (serviceStream.get() != nullptr) {
         // Only allow owner or the aaudio service to access the stream.
@@ -197,8 +177,6 @@
         if (!allowed) {
             ALOGE("AAudioService: calling uid %d cannot access stream 0x%08X owned by %d",
                   callingUserId, streamHandle, ownerUserId);
-            // We incremented the reference count so we must check if it needs to be closed.
-            checkForPendingClose(serviceStream, AAUDIO_OK);
             serviceStream.clear();
         }
     }
@@ -213,94 +191,64 @@
         ALOGE("getStreamDescription(), illegal stream handle = 0x%0x", streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-
-    aaudio_result_t result = serviceStream->getDescription(parcelable);
-    // parcelable.dump();
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->getDescription(parcelable);
 }
 
 aaudio_result_t AAudioService::startStream(aaudio_handle_t streamHandle) {
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("startStream(), illegal stream handle = 0x%0x", streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-
-    aaudio_result_t result = serviceStream->start();
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->start();
 }
 
 aaudio_result_t AAudioService::pauseStream(aaudio_handle_t streamHandle) {
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("pauseStream(), illegal stream handle = 0x%0x", streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-    aaudio_result_t result = serviceStream->pause();
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->pause();
 }
 
 aaudio_result_t AAudioService::stopStream(aaudio_handle_t streamHandle) {
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("stopStream(), illegal stream handle = 0x%0x", streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-    aaudio_result_t result = serviceStream->stop();
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->stop();
 }
 
 aaudio_result_t AAudioService::flushStream(aaudio_handle_t streamHandle) {
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("flushStream(), illegal stream handle = 0x%0x", streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-    aaudio_result_t result = serviceStream->flush();
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->flush();
 }
 
 aaudio_result_t AAudioService::registerAudioThread(aaudio_handle_t streamHandle,
                                                    pid_t clientThreadId,
-                                                   int64_t periodNanoseconds) {
-    aaudio_result_t result = AAUDIO_OK;
+                                                   int64_t /* periodNanoseconds */) {
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("registerAudioThread(), illegal stream handle = 0x%0x", streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-    if (serviceStream->getRegisteredThread() != AAudioServiceStreamBase::ILLEGAL_THREAD_ID) {
-        ALOGE("AAudioService::registerAudioThread(), thread already registered");
-        result = AAUDIO_ERROR_INVALID_STATE;
-    } else {
-        const pid_t ownerPid = IPCThreadState::self()->getCallingPid(); // TODO review
-        serviceStream->setRegisteredThread(clientThreadId);
-        int err = android::requestPriority(ownerPid, clientThreadId,
-                                           DEFAULT_AUDIO_PRIORITY, true /* isForApp */);
-        if (err != 0) {
-            ALOGE("AAudioService::registerAudioThread(%d) failed, errno = %d, priority = %d",
-                  clientThreadId, errno, DEFAULT_AUDIO_PRIORITY);
-            result = AAUDIO_ERROR_INTERNAL;
-        }
-    }
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->registerAudioThread(clientThreadId, DEFAULT_AUDIO_PRIORITY);
 }
 
 aaudio_result_t AAudioService::unregisterAudioThread(aaudio_handle_t streamHandle,
                                                      pid_t clientThreadId) {
-    aaudio_result_t result = AAUDIO_OK;
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("%s(), illegal stream handle = 0x%0x", __func__, streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-    if (serviceStream->getRegisteredThread() != clientThreadId) {
-        ALOGE("%s(), wrong thread", __func__);
-        result = AAUDIO_ERROR_ILLEGAL_ARGUMENT;
-    } else {
-        serviceStream->setRegisteredThread(0);
-    }
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->unregisterAudioThread(clientThreadId);
 }
 
 aaudio_result_t AAudioService::startClient(aaudio_handle_t streamHandle,
@@ -308,22 +256,20 @@
                                   audio_port_handle_t *clientHandle) {
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("%s(), illegal stream handle = 0x%0x", __func__, streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-    aaudio_result_t result = serviceStream->startClient(client, clientHandle);
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->startClient(client, clientHandle);
 }
 
 aaudio_result_t AAudioService::stopClient(aaudio_handle_t streamHandle,
                                           audio_port_handle_t portHandle) {
     sp<AAudioServiceStreamBase> serviceStream = convertHandleToServiceStream(streamHandle);
     if (serviceStream.get() == nullptr) {
-        ALOGE("%s(), illegal stream handle = 0x%0x", __func__, streamHandle);
+        ALOGW("%s(), invalid streamHandle = 0x%0x", __func__, streamHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
-    aaudio_result_t result = serviceStream->stopClient(portHandle);
-    return checkForPendingClose(serviceStream, result);
+    return serviceStream->stopClient(portHandle);
 }
 
 // This is only called internally when AudioFlinger wants to tear down a stream.
@@ -331,12 +277,13 @@
 aaudio_result_t AAudioService::disconnectStreamByPortHandle(audio_port_handle_t portHandle) {
     ALOGD("%s(%d) called", __func__, portHandle);
     sp<AAudioServiceStreamBase> serviceStream =
-            mStreamTracker.findStreamByPortHandleAndIncrement(portHandle);
+            mStreamTracker.findStreamByPortHandle(portHandle);
     if (serviceStream.get() == nullptr) {
         ALOGE("%s(), could not find stream with portHandle = %d", __func__, portHandle);
         return AAUDIO_ERROR_INVALID_HANDLE;
     }
+    // This is protected by a lock and will just return if already stopped.
     aaudio_result_t result = serviceStream->stop();
     serviceStream->disconnect();
-    return checkForPendingClose(serviceStream, result);
+    return result;
 }
diff --git a/services/oboeservice/AAudioService.h b/services/oboeservice/AAudioService.h
index d21b1cd..18bc33f 100644
--- a/services/oboeservice/AAudioService.h
+++ b/services/oboeservice/AAudioService.h
@@ -95,13 +95,6 @@
     sp<aaudio::AAudioServiceStreamBase> convertHandleToServiceStream(
             aaudio::aaudio_handle_t streamHandle);
 
-
-
-    bool releaseStream(const sp<aaudio::AAudioServiceStreamBase> &serviceStream);
-
-    aaudio_result_t checkForPendingClose(const sp<aaudio::AAudioServiceStreamBase> &serviceStream,
-                                         aaudio_result_t defaultResult);
-
     android::AudioClient            mAudioClient;
 
     aaudio::AAudioStreamTracker     mStreamTracker;
diff --git a/services/oboeservice/AAudioServiceEndpoint.cpp b/services/oboeservice/AAudioServiceEndpoint.cpp
index 553754e..1cffe01 100644
--- a/services/oboeservice/AAudioServiceEndpoint.cpp
+++ b/services/oboeservice/AAudioServiceEndpoint.cpp
@@ -87,15 +87,26 @@
 }
 
 void AAudioServiceEndpoint::disconnectRegisteredStreams() {
-    std::lock_guard<std::mutex> lock(mLockStreams);
+    std::vector<android::sp<AAudioServiceStreamBase>> streamsToDisconnect;
+    {
+        std::lock_guard<std::mutex> lock(mLockStreams);
+        mRegisteredStreams.swap(streamsToDisconnect);
+    }
+    // Stop and disconnect outside mLockStreams to avoid reverse
+    // ordering of AAudioServiceStreamBase::mLock and mLockStreams
     mConnected.store(false);
-    for (const auto& stream : mRegisteredStreams) {
-        ALOGD("disconnectRegisteredStreams() stop and disconnect port %d",
-              stream->getPortHandle());
+    // We need to stop all the streams before we disconnect them.
+    // Otherwise there is a race condition where the first disconnected app
+    // tries to reopen a stream as MMAP but is blocked by the second stream,
+    // which hasn't stopped yet. Then the first app ends up with a Legacy stream.
+    for (const auto &stream : streamsToDisconnect) {
+        ALOGD("%s() - stop(), port = %d", __func__, stream->getPortHandle());
         stream->stop();
+    }
+    for (const auto &stream : streamsToDisconnect) {
+        ALOGD("%s() - disconnect(), port = %d", __func__, stream->getPortHandle());
         stream->disconnect();
     }
-    mRegisteredStreams.clear();
 }
 
 aaudio_result_t AAudioServiceEndpoint::registerStream(sp<AAudioServiceStreamBase>stream) {
diff --git a/services/oboeservice/AAudioServiceEndpointShared.cpp b/services/oboeservice/AAudioServiceEndpointShared.cpp
index 0a415fd..0d79cdd 100644
--- a/services/oboeservice/AAudioServiceEndpointShared.cpp
+++ b/services/oboeservice/AAudioServiceEndpointShared.cpp
@@ -166,13 +166,11 @@
 
 aaudio_result_t AAudioServiceEndpointShared::stopStream(sp<AAudioServiceStreamBase> sharedStream,
                                                         audio_port_handle_t clientHandle) {
-    // Don't lock here because the disconnectRegisteredStreams also uses the lock.
-
     // Ignore result.
     (void) getStreamInternal()->stopClient(clientHandle);
 
     if (--mRunningStreamCount == 0) { // atomic
-        stopSharingThread();
+        stopSharingThread(); // the sharing thread locks mLockStreams
         getStreamInternal()->requestStop();
     }
     return AAUDIO_OK;
diff --git a/services/oboeservice/AAudioServiceStreamBase.cpp b/services/oboeservice/AAudioServiceStreamBase.cpp
index 880a3d7..4a99ae0 100644
--- a/services/oboeservice/AAudioServiceStreamBase.cpp
+++ b/services/oboeservice/AAudioServiceStreamBase.cpp
@@ -22,6 +22,8 @@
 #include <iostream>
 #include <mutex>
 
+#include <mediautils/SchedulingPolicyService.h>
+
 #include "binding/IAAudioService.h"
 #include "binding/AAudioServiceMessage.h"
 #include "utility/AudioClock.h"
@@ -126,12 +128,17 @@
 }
 
 aaudio_result_t AAudioServiceStreamBase::close() {
+    std::lock_guard<std::mutex> lock(mLock);
+    return close_l();
+}
+
+aaudio_result_t AAudioServiceStreamBase::close_l() {
     aaudio_result_t result = AAUDIO_OK;
     if (getState() == AAUDIO_STREAM_STATE_CLOSED) {
         return AAUDIO_OK;
     }
 
-    stop();
+    stop_l();
 
     sp<AAudioServiceEndpoint> endpoint = mServiceEndpointWeak.promote();
     if (endpoint == nullptr) {
@@ -142,7 +149,7 @@
         endpointManager.closeEndpoint(endpoint);
 
         // AAudioService::closeStream() prevents two threads from closing at the same time.
-        mServiceEndpoint.clear(); // endpoint will hold the pointer until this method returns.
+        mServiceEndpoint.clear(); // endpoint will hold the pointer after this method returns.
     }
 
     {
@@ -172,7 +179,14 @@
  * An AAUDIO_SERVICE_EVENT_STARTED will be sent to the client when complete.
  */
 aaudio_result_t AAudioServiceStreamBase::start() {
-    aaudio_result_t result = AAUDIO_OK;
+    std::lock_guard<std::mutex> lock(mLock);
+
+    if (auto state = getState();
+        state == AAUDIO_STREAM_STATE_CLOSED || state == AAUDIO_STREAM_STATE_DISCONNECTED) {
+        ALOGW("%s() already CLOSED, returns INVALID_STATE, handle = %d",
+                __func__, getHandle());
+        return AAUDIO_ERROR_INVALID_STATE;
+    }
 
     if (isRunning()) {
         return AAUDIO_OK;
@@ -185,7 +199,7 @@
     mAtomicStreamTimestamp.clear();
 
     mClientHandle = AUDIO_PORT_HANDLE_NONE;
-    result = startDevice();
+    aaudio_result_t result = startDevice();
     if (result != AAUDIO_OK) goto error;
 
     // This should happen at the end of the start.
@@ -198,11 +212,16 @@
     return result;
 
 error:
-    disconnect();
+    disconnect_l();
     return result;
 }
 
 aaudio_result_t AAudioServiceStreamBase::pause() {
+    std::lock_guard<std::mutex> lock(mLock);
+    return pause_l();
+}
+
+aaudio_result_t AAudioServiceStreamBase::pause_l() {
     aaudio_result_t result = AAUDIO_OK;
     if (!isRunning()) {
         return result;
@@ -214,7 +233,7 @@
 
     result = stopTimestampThread();
     if (result != AAUDIO_OK) {
-        disconnect();
+        disconnect_l();
         return result;
     }
 
@@ -226,7 +245,7 @@
     result = endpoint->stopStream(this, mClientHandle);
     if (result != AAUDIO_OK) {
         ALOGE("%s() mServiceEndpoint returned %d, %s", __func__, result, getTypeText());
-        disconnect(); // TODO should we return or pause Base first?
+        disconnect_l(); // TODO should we return or pause Base first?
     }
 
     sendServiceEvent(AAUDIO_SERVICE_EVENT_PAUSED);
@@ -235,6 +254,11 @@
 }
 
 aaudio_result_t AAudioServiceStreamBase::stop() {
+    std::lock_guard<std::mutex> lock(mLock);
+    return stop_l();
+}
+
+aaudio_result_t AAudioServiceStreamBase::stop_l() {
     aaudio_result_t result = AAUDIO_OK;
     if (!isRunning()) {
         return result;
@@ -247,7 +271,7 @@
     sendCurrentTimestamp(); // warning - this calls a virtual function
     result = stopTimestampThread();
     if (result != AAUDIO_OK) {
-        disconnect();
+        disconnect_l();
         return result;
     }
 
@@ -260,7 +284,7 @@
     result = endpoint->stopStream(this, mClientHandle);
     if (result != AAUDIO_OK) {
         ALOGE("%s() stopStream returned %d, %s", __func__, result, getTypeText());
-        disconnect();
+        disconnect_l();
         // TODO what to do with result here?
     }
 
@@ -279,6 +303,7 @@
 }
 
 aaudio_result_t AAudioServiceStreamBase::flush() {
+    std::lock_guard<std::mutex> lock(mLock);
     aaudio_result_t result = AAudio_isFlushAllowed(getState());
     if (result != AAUDIO_OK) {
         return result;
@@ -319,12 +344,60 @@
 }
 
 void AAudioServiceStreamBase::disconnect() {
-    if (getState() != AAUDIO_STREAM_STATE_DISCONNECTED) {
+    std::lock_guard<std::mutex> lock(mLock);
+    disconnect_l();
+}
+
+void AAudioServiceStreamBase::disconnect_l() {
+    if (getState() != AAUDIO_STREAM_STATE_DISCONNECTED
+        && getState() != AAUDIO_STREAM_STATE_CLOSED) {
         sendServiceEvent(AAUDIO_SERVICE_EVENT_DISCONNECTED);
         setState(AAUDIO_STREAM_STATE_DISCONNECTED);
     }
 }
 
+aaudio_result_t AAudioServiceStreamBase::registerAudioThread(pid_t clientThreadId,
+        int priority) {
+    std::lock_guard<std::mutex> lock(mLock);
+    aaudio_result_t result = AAUDIO_OK;
+    if (getRegisteredThread() != AAudioServiceStreamBase::ILLEGAL_THREAD_ID) {
+        ALOGE("AAudioService::registerAudioThread(), thread already registered");
+        result = AAUDIO_ERROR_INVALID_STATE;
+    } else {
+        const pid_t ownerPid = IPCThreadState::self()->getCallingPid(); // TODO review
+        setRegisteredThread(clientThreadId);
+        int err = android::requestPriority(ownerPid, clientThreadId,
+                                           priority, true /* isForApp */);
+        if (err != 0) {
+            ALOGE("AAudioService::registerAudioThread(%d) failed, errno = %d, priority = %d",
+                  clientThreadId, errno, priority);
+            result = AAUDIO_ERROR_INTERNAL;
+        }
+    }
+    return result;
+}
+
+aaudio_result_t AAudioServiceStreamBase::unregisterAudioThread(pid_t clientThreadId) {
+    std::lock_guard<std::mutex> lock(mLock);
+    aaudio_result_t result = AAUDIO_OK;
+    if (getRegisteredThread() != clientThreadId) {
+        ALOGE("%s(), wrong thread", __func__);
+        result = AAUDIO_ERROR_ILLEGAL_ARGUMENT;
+    } else {
+        setRegisteredThread(0);
+    }
+    return result;
+}
+
+void AAudioServiceStreamBase::setState(aaudio_stream_state_t state) {
+    // CLOSED is a final state.
+    if (mState != AAUDIO_STREAM_STATE_CLOSED) {
+        mState = state;
+    } else {
+        ALOGW_IF(mState != state, "%s(%d) when already CLOSED", __func__, state);
+    }
+}
+
 aaudio_result_t AAudioServiceStreamBase::sendServiceEvent(aaudio_service_event_t event,
                                                           double  dataDouble) {
     AAudioServiceMessage command;
@@ -422,6 +495,7 @@
  * used to communicate with the underlying HAL or Service.
  */
 aaudio_result_t AAudioServiceStreamBase::getDescription(AudioEndpointParcelable &parcelable) {
+    std::lock_guard<std::mutex> lock(mLock);
     {
         std::lock_guard<std::mutex> lock(mUpMessageQueueLock);
         if (mUpMessageQueue == nullptr) {
diff --git a/services/oboeservice/AAudioServiceStreamBase.h b/services/oboeservice/AAudioServiceStreamBase.h
index 097bc64..32db728 100644
--- a/services/oboeservice/AAudioServiceStreamBase.h
+++ b/services/oboeservice/AAudioServiceStreamBase.h
@@ -74,7 +74,7 @@
      */
     virtual aaudio_result_t open(const aaudio::AAudioStreamRequest &request) = 0;
 
-    virtual aaudio_result_t close();
+    aaudio_result_t close();
 
     /**
      * Start the flow of audio data.
@@ -82,7 +82,7 @@
      * This is not guaranteed to be synchronous but it currently is.
      * An AAUDIO_SERVICE_EVENT_STARTED will be sent to the client when complete.
      */
-    virtual aaudio_result_t start();
+    aaudio_result_t start();
 
     /**
      * Stop the flow of data so that start() can resume without loss of data.
@@ -90,7 +90,7 @@
      * This is not guaranteed to be synchronous but it currently is.
      * An AAUDIO_SERVICE_EVENT_PAUSED will be sent to the client when complete.
     */
-    virtual aaudio_result_t pause();
+    aaudio_result_t pause();
 
     /**
      * Stop the flow of data after the currently queued data has finished playing.
@@ -99,17 +99,14 @@
      * An AAUDIO_SERVICE_EVENT_STOPPED will be sent to the client when complete.
      *
      */
-    virtual aaudio_result_t stop();
-
-    aaudio_result_t stopTimestampThread();
+    aaudio_result_t stop();
 
     /**
      * Discard any data held by the underlying HAL or Service.
      *
      * An AAUDIO_SERVICE_EVENT_FLUSHED will be sent to the client when complete.
      */
-    virtual aaudio_result_t flush();
-
+    aaudio_result_t flush();
 
     virtual aaudio_result_t startClient(const android::AudioClient& client __unused,
                                         audio_port_handle_t *clientHandle __unused) {
@@ -122,29 +119,19 @@
         return AAUDIO_ERROR_UNAVAILABLE;
     }
 
+    aaudio_result_t registerAudioThread(pid_t clientThreadId, int priority);
+
+    aaudio_result_t unregisterAudioThread(pid_t clientThreadId);
+
     bool isRunning() const {
         return mState == AAUDIO_STREAM_STATE_STARTED;
     }
 
-    // -------------------------------------------------------------------
-
-    /**
-     * Send a message to the client with an int64_t data value.
-     */
-    aaudio_result_t sendServiceEvent(aaudio_service_event_t event,
-                                     int64_t dataLong = 0);
-    /**
-     * Send a message to the client with an double data value.
-     */
-    aaudio_result_t sendServiceEvent(aaudio_service_event_t event,
-                                     double  dataDouble);
-
     /**
      * Fill in a parcelable description of stream.
      */
     aaudio_result_t getDescription(AudioEndpointParcelable &parcelable);
 
-
     void setRegisteredThread(pid_t pid) {
         mRegisteredClientThread = pid;
     }
@@ -258,9 +245,13 @@
     aaudio_result_t open(const aaudio::AAudioStreamRequest &request,
                          aaudio_sharing_mode_t sharingMode);
 
-    void setState(aaudio_stream_state_t state) {
-        mState = state;
-    }
+    // These must be called under mLock
+    virtual aaudio_result_t close_l();
+    virtual aaudio_result_t pause_l();
+    virtual aaudio_result_t stop_l();
+    void disconnect_l();
+
+    void setState(aaudio_stream_state_t state);
 
     /**
      * Device specific startup.
@@ -292,6 +283,10 @@
     SharedRingBuffer*       mUpMessageQueue;
     std::mutex              mUpMessageQueueLock;
 
+    // Locking order is important.
+    // Always acquire mLock before acquiring AAudioServiceEndpoint::mLockStreams
+    std::mutex              mLock; // Prevent start/stop/close etcetera from colliding
+
     AAudioThread            mTimestampThread;
     // This is used by one thread to tell another thread to exit. So it must be atomic.
     std::atomic<bool>       mThreadEnabled{false};
@@ -313,6 +308,19 @@
 
 private:
 
+    aaudio_result_t stopTimestampThread();
+
+    /**
+     * Send a message to the client with an int64_t data value.
+     */
+    aaudio_result_t sendServiceEvent(aaudio_service_event_t event,
+                                     int64_t dataLong = 0);
+    /**
+     * Send a message to the client with a double data value.
+     */
+    aaudio_result_t sendServiceEvent(aaudio_service_event_t event,
+                                     double dataDouble);
+
     /**
      * @return true if the queue is getting full.
      */
diff --git a/services/oboeservice/AAudioServiceStreamMMAP.cpp b/services/oboeservice/AAudioServiceStreamMMAP.cpp
index 837b080..8e4217a 100644
--- a/services/oboeservice/AAudioServiceStreamMMAP.cpp
+++ b/services/oboeservice/AAudioServiceStreamMMAP.cpp
@@ -49,16 +49,6 @@
         , mInService(inService) {
 }
 
-aaudio_result_t AAudioServiceStreamMMAP::close() {
-    if (getState() == AAUDIO_STREAM_STATE_CLOSED) {
-        return AAUDIO_OK;
-    }
-
-    stop();
-
-    return AAudioServiceStreamBase::close();
-}
-
 // Open stream on HAL and pass information about the shared memory buffer back to the client.
 aaudio_result_t AAudioServiceStreamMMAP::open(const aaudio::AAudioStreamRequest &request) {
 
@@ -102,11 +92,11 @@
 }
 
 // Stop the flow of data such that start() can resume with loss of data.
-aaudio_result_t AAudioServiceStreamMMAP::pause() {
+aaudio_result_t AAudioServiceStreamMMAP::pause_l() {
     if (!isRunning()) {
         return AAUDIO_OK;
     }
-    aaudio_result_t result = AAudioServiceStreamBase::pause();
+    aaudio_result_t result = AAudioServiceStreamBase::pause_l();
     // TODO put before base::pause()?
     if (!mInService) {
         (void) stopClient(mClientHandle);
@@ -114,11 +104,11 @@
     return result;
 }
 
-aaudio_result_t AAudioServiceStreamMMAP::stop() {
+aaudio_result_t AAudioServiceStreamMMAP::stop_l() {
     if (!isRunning()) {
         return AAUDIO_OK;
     }
-    aaudio_result_t result = AAudioServiceStreamBase::stop();
+    aaudio_result_t result = AAudioServiceStreamBase::stop_l();
     // TODO put before base::stop()?
     if (!mInService) {
         (void) stopClient(mClientHandle);
diff --git a/services/oboeservice/AAudioServiceStreamMMAP.h b/services/oboeservice/AAudioServiceStreamMMAP.h
index 1509f7d..141174e 100644
--- a/services/oboeservice/AAudioServiceStreamMMAP.h
+++ b/services/oboeservice/AAudioServiceStreamMMAP.h
@@ -52,26 +52,24 @@
 
     aaudio_result_t open(const aaudio::AAudioStreamRequest &request) override;
 
+    aaudio_result_t startClient(const android::AudioClient& client,
+                                audio_port_handle_t *clientHandle) override;
+
+    aaudio_result_t stopClient(audio_port_handle_t clientHandle) override;
+
+    const char *getTypeText() const override { return "MMAP"; }
+
+protected:
+
     /**
      * Stop the flow of data so that start() can resume without loss of data.
      *
      * This is not guaranteed to be synchronous but it currently is.
      * An AAUDIO_SERVICE_EVENT_PAUSED will be sent to the client when complete.
     */
-    aaudio_result_t pause() override;
+    aaudio_result_t pause_l() override;
 
-    aaudio_result_t stop() override;
-
-    aaudio_result_t startClient(const android::AudioClient& client,
-                                audio_port_handle_t *clientHandle) override;
-
-    aaudio_result_t stopClient(audio_port_handle_t clientHandle) override;
-
-    aaudio_result_t close() override;
-
-    const char *getTypeText() const override { return "MMAP"; }
-
-protected:
+    aaudio_result_t stop_l() override;
 
     aaudio_result_t getAudioDataDescription(AudioEndpointParcelable &parcelable) override;
 
diff --git a/services/oboeservice/AAudioServiceStreamShared.cpp b/services/oboeservice/AAudioServiceStreamShared.cpp
index 2ca847a..01b1c2e 100644
--- a/services/oboeservice/AAudioServiceStreamShared.cpp
+++ b/services/oboeservice/AAudioServiceStreamShared.cpp
@@ -203,9 +203,8 @@
     return result;
 }
 
-
-aaudio_result_t AAudioServiceStreamShared::close()  {
-    aaudio_result_t result = AAudioServiceStreamBase::close();
+aaudio_result_t AAudioServiceStreamShared::close_l()  {
+    aaudio_result_t result = AAudioServiceStreamBase::close_l();
 
     {
         std::lock_guard<std::mutex> lock(mAudioDataQueueLock);
diff --git a/services/oboeservice/AAudioServiceStreamShared.h b/services/oboeservice/AAudioServiceStreamShared.h
index 61769b5..abcb782 100644
--- a/services/oboeservice/AAudioServiceStreamShared.h
+++ b/services/oboeservice/AAudioServiceStreamShared.h
@@ -52,7 +52,7 @@
 
     aaudio_result_t open(const aaudio::AAudioStreamRequest &request) override;
 
-    aaudio_result_t close() override;
+    aaudio_result_t close_l() override;
 
     /**
      * This must be locked when calling getAudioDataFifoBuffer_l() and while
diff --git a/services/oboeservice/AAudioStreamTracker.cpp b/services/oboeservice/AAudioStreamTracker.cpp
index 3328159..8e66b94 100644
--- a/services/oboeservice/AAudioStreamTracker.cpp
+++ b/services/oboeservice/AAudioStreamTracker.cpp
@@ -30,32 +30,20 @@
 using namespace android;
 using namespace aaudio;
 
-sp<AAudioServiceStreamBase> AAudioStreamTracker::decrementAndRemoveStreamByHandle(
+int32_t AAudioStreamTracker::removeStreamByHandle(
         aaudio_handle_t streamHandle) {
     std::lock_guard<std::mutex> lock(mHandleLock);
-    sp<AAudioServiceStreamBase> serviceStream;
-    auto it = mStreamsByHandle.find(streamHandle);
-    if (it != mStreamsByHandle.end()) {
-        sp<AAudioServiceStreamBase> tempStream = it->second;
-        // Does the caller need to close the stream?
-        // The reference count should never be negative.
-        // But it is safer to check for <= 0 than == 0.
-        if ((tempStream->decrementServiceReferenceCount_l() <= 0) && tempStream->isCloseNeeded()) {
-            serviceStream = tempStream; // Only return stream if ready to be closed.
-            mStreamsByHandle.erase(it);
-        }
-    }
-    return serviceStream;
+    auto count = mStreamsByHandle.erase(streamHandle);
+    return static_cast<int32_t>(count);
 }
 
-sp<AAudioServiceStreamBase> AAudioStreamTracker::getStreamByHandleAndIncrement(
+sp<AAudioServiceStreamBase> AAudioStreamTracker::getStreamByHandle(
         aaudio_handle_t streamHandle) {
     std::lock_guard<std::mutex> lock(mHandleLock);
     sp<AAudioServiceStreamBase> serviceStream;
     auto it = mStreamsByHandle.find(streamHandle);
     if (it != mStreamsByHandle.end()) {
         serviceStream = it->second;
-        serviceStream->incrementServiceReferenceCount_l();
     }
     return serviceStream;
 }
@@ -63,7 +51,7 @@
 // The port handle is only available when the stream is started.
 // So we have to iterate over all the streams.
 // Luckily this rarely happens.
-sp<AAudioServiceStreamBase> AAudioStreamTracker::findStreamByPortHandleAndIncrement(
+sp<AAudioServiceStreamBase> AAudioStreamTracker::findStreamByPortHandle(
         audio_port_handle_t portHandle) {
     std::lock_guard<std::mutex> lock(mHandleLock);
     sp<AAudioServiceStreamBase> serviceStream;
@@ -72,7 +60,6 @@
         auto candidate = it->second;
         if (candidate->getPortHandle() == portHandle) {
             serviceStream = candidate;
-            serviceStream->incrementServiceReferenceCount_l();
             break;
         }
         it++;
diff --git a/services/oboeservice/AAudioStreamTracker.h b/services/oboeservice/AAudioStreamTracker.h
index 57ec426..d1301a2 100644
--- a/services/oboeservice/AAudioStreamTracker.h
+++ b/services/oboeservice/AAudioStreamTracker.h
@@ -32,25 +32,20 @@
 
 public:
     /**
-     * Find the stream associated with the handle.
-     * Decrement its reference counter. If zero and the stream needs
-     * to be closed then remove the stream and return a pointer to the stream.
-     * Otherwise return null if it does not need to be closed.
+     * Remove any streams with the matching handle.
      *
      * @param streamHandle
-     * @return strong pointer to the stream if it needs to be closed, or nullptr
+     * @return number of streams removed
      */
-    android::sp<AAudioServiceStreamBase> decrementAndRemoveStreamByHandle(
-            aaudio_handle_t streamHandle);
+    int32_t removeStreamByHandle(aaudio_handle_t streamHandle);
 
     /**
      * Look up a stream based on the handle.
-     * Increment its service reference count if found.
      *
      * @param streamHandle
      * @return strong pointer to the stream if found, or nullptr
      */
-    android::sp<aaudio::AAudioServiceStreamBase> getStreamByHandleAndIncrement(
+    android::sp<aaudio::AAudioServiceStreamBase> getStreamByHandle(
             aaudio_handle_t streamHandle);
 
     /**
@@ -60,7 +55,7 @@
      * @param portHandle
      * @return strong pointer to the stream if found, or nullptr
      */
-    android::sp<aaudio::AAudioServiceStreamBase> findStreamByPortHandleAndIncrement(
+    android::sp<aaudio::AAudioServiceStreamBase> findStreamByPortHandle(
             audio_port_handle_t portHandle);
 
     /**