diff --git a/media/libaudioclient/IAudioFlinger.cpp b/media/libaudioclient/IAudioFlinger.cpp
index 77cfe4d..8c9d3c1 100644
--- a/media/libaudioclient/IAudioFlinger.cpp
+++ b/media/libaudioclient/IAudioFlinger.cpp
@@ -24,6 +24,7 @@
 
 #include <binder/IPCThreadState.h>
 #include <binder/Parcel.h>
+#include <cutils/multiuser.h>
 #include <media/TimeCheck.h>
 #include <private/android_filesystem_config.h>
 
@@ -904,8 +905,7 @@
         case SET_MIC_MUTE:
         case SET_LOW_RAM_DEVICE:
         case SYSTEM_READY: {
-            uid_t multiUserClientUid = IPCThreadState::self()->getCallingUid() % AID_USER_OFFSET;
-            if (multiUserClientUid >= AID_APP_START) {
+            if (multiuser_get_app_id(IPCThreadState::self()->getCallingUid()) >= AID_APP_START) {
                 ALOGW("%s: transaction %d received from PID %d unauthorized UID %d",
                       __func__, code, IPCThreadState::self()->getCallingPid(),
                       IPCThreadState::self()->getCallingUid());
diff --git a/media/libaudioclient/IAudioPolicyService.cpp b/media/libaudioclient/IAudioPolicyService.cpp
index f87fcc4..35f9727 100644
--- a/media/libaudioclient/IAudioPolicyService.cpp
+++ b/media/libaudioclient/IAudioPolicyService.cpp
@@ -24,7 +24,7 @@
 
 #include <binder/IPCThreadState.h>
 #include <binder/Parcel.h>
-
+#include <cutils/multiuser.h>
 #include <media/AudioEffect.h>
 #include <media/IAudioPolicyService.h>
 #include <media/TimeCheck.h>
@@ -875,8 +875,7 @@
         case SET_MASTER_MONO:
         case START_AUDIO_SOURCE:
         case STOP_AUDIO_SOURCE: {
-            uid_t multiUserClientUid = IPCThreadState::self()->getCallingUid() % AID_USER_OFFSET;
-            if (multiUserClientUid >= AID_APP_START) {
+            if (multiuser_get_app_id(IPCThreadState::self()->getCallingUid()) >= AID_APP_START) {
                 ALOGW("%s: transaction %d received from PID %d unauthorized UID %d",
                       __func__, code, IPCThreadState::self()->getCallingPid(),
                       IPCThreadState::self()->getCallingUid());
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 54121cd..949b570 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -28,6 +28,7 @@
 
 #include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
+#include <cutils/multiuser.h>
 #include <utils/Log.h>
 #include <utils/Trace.h>
 #include <binder/Parcel.h>
@@ -1178,16 +1179,59 @@
     }
 }
 
+// Filter reserved keys from setParameters() before forwarding to audio HAL or acting upon.
+// Some keys are used for audio routing and audio path configuration and should be reserved for use
+// by audio policy and audio flinger for functional, privacy and security reasons.
+void AudioFlinger::filterReservedParameters(String8& keyValuePairs, uid_t callingUid)
+{
+    static const String8 kReservedParameters[] = {
+        String8(AudioParameter::keyRouting),
+        String8(AudioParameter::keySamplingRate),
+        String8(AudioParameter::keyFormat),
+        String8(AudioParameter::keyChannels),
+        String8(AudioParameter::keyFrameCount),
+        String8(AudioParameter::keyInputSource),
+        String8(AudioParameter::keyMonoOutput),
+        String8(AudioParameter::keyStreamConnect),
+        String8(AudioParameter::keyStreamDisconnect),
+        String8(AudioParameter::keyStreamSupportedFormats),
+        String8(AudioParameter::keyStreamSupportedChannels),
+        String8(AudioParameter::keyStreamSupportedSamplingRates),
+    };
+
+    // multiuser friendly app ID check for requests coming from audioserver
+    if (multiuser_get_app_id(callingUid) == AID_AUDIOSERVER) {
+        return;
+    }
+
+    AudioParameter param = AudioParameter(keyValuePairs);
+    String8 value;
+    for (auto& key : kReservedParameters) {
+        if (param.get(key, value) == NO_ERROR) {
+            ALOGW("%s: filtering key %s value %s from uid %d",
+                  __func__, key.string(), value.string(), callingUid);
+            param.remove(key);
+        }
+    }
+    keyValuePairs = param.toString();
+}
+
 status_t AudioFlinger::setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs)
 {
-    ALOGV("setParameters(): io %d, keyvalue %s, calling pid %d",
-            ioHandle, keyValuePairs.string(), IPCThreadState::self()->getCallingPid());
+    ALOGV("setParameters(): io %d, keyvalue %s, calling pid %d calling uid %d",
+            ioHandle, keyValuePairs.string(),
+            IPCThreadState::self()->getCallingPid(), IPCThreadState::self()->getCallingUid());
 
     // check calling permissions
     if (!settingsAllowed()) {
         return PERMISSION_DENIED;
     }
 
+    String8 filteredKeyValuePairs = keyValuePairs;
+    filterReservedParameters(filteredKeyValuePairs, IPCThreadState::self()->getCallingUid());
+
+    ALOGV("%s: filtered keyvalue %s", __func__, filteredKeyValuePairs.string());
+
     // AUDIO_IO_HANDLE_NONE means the parameters are global to the audio hardware interface
     if (ioHandle == AUDIO_IO_HANDLE_NONE) {
         Mutex::Autolock _l(mLock);
@@ -1198,7 +1242,7 @@
             mHardwareStatus = AUDIO_HW_SET_PARAMETER;
             for (size_t i = 0; i < mAudioHwDevs.size(); i++) {
                 sp<DeviceHalInterface> dev = mAudioHwDevs.valueAt(i)->hwDevice();
-                status_t result = dev->setParameters(keyValuePairs);
+                status_t result = dev->setParameters(filteredKeyValuePairs);
                 // return success if at least one audio device accepts the parameters as not all
                 // HALs are requested to support all parameters. If no audio device supports the
                 // requested parameters, the last error is reported.
@@ -1209,7 +1253,7 @@
             mHardwareStatus = AUDIO_HW_IDLE;
         }
         // disable AEC and NS if the device is a BT SCO headset supporting those pre processings
-        AudioParameter param = AudioParameter(keyValuePairs);
+        AudioParameter param = AudioParameter(filteredKeyValuePairs);
         String8 value;
         if (param.get(String8(AudioParameter::keyBtNrec), value) == NO_ERROR) {
             bool btNrecIsOff = (value == AudioParameter::valueOff);
@@ -1242,16 +1286,16 @@
             }
         } else if (thread == primaryPlaybackThread_l()) {
             // indicate output device change to all input threads for pre processing
-            AudioParameter param = AudioParameter(keyValuePairs);
+            AudioParameter param = AudioParameter(filteredKeyValuePairs);
             int value;
             if ((param.getInt(String8(AudioParameter::keyRouting), value) == NO_ERROR) &&
                     (value != 0)) {
-                broacastParametersToRecordThreads_l(keyValuePairs);
+                broacastParametersToRecordThreads_l(filteredKeyValuePairs);
             }
         }
     }
     if (thread != 0) {
-        return thread->setParameters(keyValuePairs);
+        return thread->setParameters(filteredKeyValuePairs);
     }
     return BAD_VALUE;
 }
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 3302868..963a87d 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -798,6 +798,8 @@
 
     status_t    checkStreamType(audio_stream_type_t stream) const;
 
+    void        filterReservedParameters(String8& keyValuePairs, uid_t callingUid);
+
 #ifdef TEE_SINK
     // all record threads serially share a common tee sink, which is re-created on format change
     sp<NBAIO_Sink>   mRecordTeeSink;
diff --git a/services/audiopolicy/service/AudioPolicyService.cpp b/services/audiopolicy/service/AudioPolicyService.cpp
index 13bf605..f3cddc3 100644
--- a/services/audiopolicy/service/AudioPolicyService.cpp
+++ b/services/audiopolicy/service/AudioPolicyService.cpp
@@ -26,6 +26,7 @@
 #include <sys/time.h>
 #include <binder/IServiceManager.h>
 #include <utils/Log.h>
+#include <cutils/multiuser.h>
 #include <cutils/properties.h>
 #include <binder/IPCThreadState.h>
 #include <binder/ActivityManager.h>
@@ -274,7 +275,7 @@
 void AudioPolicyService::NotificationClient::onDynamicPolicyMixStateUpdate(
         const String8& regId, int32_t state)
 {
-    if (mAudioPolicyServiceClient != 0 && (mUid % AID_USER_OFFSET) < AID_APP_START) {
+    if (mAudioPolicyServiceClient != 0 && multiuser_get_app_id(mUid) < AID_APP_START) {
         mAudioPolicyServiceClient->onDynamicPolicyMixStateUpdate(regId, state);
     }
 }
@@ -284,7 +285,7 @@
         const audio_config_base_t *clientConfig, const audio_config_base_t *deviceConfig,
         audio_patch_handle_t patchHandle)
 {
-    if (mAudioPolicyServiceClient != 0 && (mUid % AID_USER_OFFSET) < AID_APP_START) {
+    if (mAudioPolicyServiceClient != 0 && multiuser_get_app_id(mUid) < AID_APP_START) {
         mAudioPolicyServiceClient->onRecordingConfigurationUpdate(event, clientInfo,
                 clientConfig, deviceConfig, patchHandle);
     }
@@ -577,7 +578,7 @@
 }
 
 bool AudioPolicyService::UidPolicy::isServiceUid(uid_t uid) const {
-    return uid % AID_USER_OFFSET < AID_APP_START;
+    return multiuser_get_app_id(uid) < AID_APP_START;
 }
 
 void AudioPolicyService::UidPolicy::notifyService(uid_t uid, bool active) {