diff --git a/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java b/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java
index bba61d7..6f017dc 100644
--- a/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java
+++ b/Tethering/src/android/net/ip/RouterAdvertisementDaemon.java
@@ -668,7 +668,7 @@
     }
 
     private final class UnicastResponder extends Thread {
-        private final InetSocketAddress mSolicitor = new InetSocketAddress();
+        private final InetSocketAddress mSolicitor = new InetSocketAddress(0);
         // The recycled buffer for receiving Router Solicitations from clients.
         // If the RS is larger than IPV6_MIN_MTU the packets are truncated.
         // This is fine since currently only byte 0 is examined anyway.
diff --git a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
index efa711b..2119791 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
@@ -71,7 +71,6 @@
 import android.net.LinkProperties;
 import android.net.Network;
 import android.net.NetworkInfo;
-import android.net.NetworkUtils;
 import android.net.TetherStatesParcel;
 import android.net.TetheringConfigurationParcel;
 import android.net.ip.IpServer;
@@ -291,13 +290,6 @@
         filter.addAction(WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION);
         filter.addAction(UserManager.ACTION_USER_RESTRICTIONS_CHANGED);
         mContext.registerReceiver(mStateReceiver, filter, null, handler);
-
-        filter = new IntentFilter();
-        filter.addAction(Intent.ACTION_MEDIA_SHARED);
-        filter.addAction(Intent.ACTION_MEDIA_UNSHARED);
-        filter.addDataScheme("file");
-        mContext.registerReceiver(mStateReceiver, filter, null, handler);
-
     }
 
     private class TetheringThreadExecutor implements Executor {
@@ -1384,12 +1376,17 @@
 
         protected void setDnsForwarders(final Network network, final LinkProperties lp) {
             // TODO: Set v4 and/or v6 DNS per available connectivity.
-            String[] dnsServers = mConfig.defaultIPv4DNS;
             final Collection<InetAddress> dnses = lp.getDnsServers();
             // TODO: Properly support the absence of DNS servers.
+            final String[] dnsServers;
             if (dnses != null && !dnses.isEmpty()) {
-                // TODO: remove this invocation of NetworkUtils.makeStrings().
-                dnsServers = NetworkUtils.makeStrings(dnses);
+                dnsServers = new String[dnses.size()];
+                int i = 0;
+                for (InetAddress dns : dnses) {
+                    dnsServers[i++] = dns.getHostAddress();
+                }
+            } else {
+                dnsServers = mConfig.defaultIPv4DNS;
             }
             final int netId = (network != null) ? network.netId : NETID_UNSET;
             try {
diff --git a/Tethering/src/com/android/server/connectivity/tethering/TetheringConfiguration.java b/Tethering/src/com/android/server/connectivity/tethering/TetheringConfiguration.java
index 490614b..397ba8a 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/TetheringConfiguration.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/TetheringConfiguration.java
@@ -37,7 +37,6 @@
 import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.Resources;
-import android.net.ConnectivityManager;
 import android.net.TetheringConfigurationParcel;
 import android.net.util.SharedLog;
 import android.provider.Settings;
@@ -179,8 +178,8 @@
 
         pw.print("chooseUpstreamAutomatically: ");
         pw.println(chooseUpstreamAutomatically);
-        dumpStringArray(pw, "preferredUpstreamIfaceTypes",
-                preferredUpstreamNames(preferredUpstreamIfaceTypes));
+        pw.print("legacyPreredUpstreamIfaceTypes: ");
+        pw.println(Arrays.toString(toIntArray(preferredUpstreamIfaceTypes)));
 
         dumpStringArray(pw, "legacyDhcpRanges", legacyDhcpRanges);
         dumpStringArray(pw, "defaultIPv4DNS", defaultIPv4DNS);
@@ -205,7 +204,7 @@
         sj.add(String.format("isDunRequired:%s", isDunRequired));
         sj.add(String.format("chooseUpstreamAutomatically:%s", chooseUpstreamAutomatically));
         sj.add(String.format("preferredUpstreamIfaceTypes:%s",
-                makeString(preferredUpstreamNames(preferredUpstreamIfaceTypes))));
+                toIntArray(preferredUpstreamIfaceTypes)));
         sj.add(String.format("provisioningApp:%s", makeString(provisioningApp)));
         sj.add(String.format("provisioningAppNoUi:%s", provisioningAppNoUi));
         sj.add(String.format("enableLegacyDhcpServer:%s", enableLegacyDhcpServer));
@@ -234,21 +233,6 @@
         return sj.toString();
     }
 
-    private static String[] preferredUpstreamNames(Collection<Integer> upstreamTypes) {
-        String[] upstreamNames = null;
-
-        if (upstreamTypes != null) {
-            upstreamNames = new String[upstreamTypes.size()];
-            int i = 0;
-            for (Integer netType : upstreamTypes) {
-                upstreamNames[i] = ConnectivityManager.getNetworkTypeName(netType);
-                i++;
-            }
-        }
-
-        return upstreamNames;
-    }
-
     /** Check whether dun is required. */
     public static boolean checkDunRequired(Context ctx) {
         final TelephonyManager tm = (TelephonyManager) ctx.getSystemService(TELEPHONY_SERVICE);
@@ -388,6 +372,15 @@
         return false;
     }
 
+    private static int[] toIntArray(Collection<Integer> values) {
+        final int[] result = new int[values.size()];
+        int index = 0;
+        for (Integer value : values) {
+            result[index++] = value;
+        }
+        return result;
+    }
+
     /**
      * Convert this TetheringConfiguration to a TetheringConfigurationParcel.
      */
@@ -400,12 +393,7 @@
         parcel.isDunRequired = isDunRequired;
         parcel.chooseUpstreamAutomatically = chooseUpstreamAutomatically;
 
-        int[] preferredTypes = new int[preferredUpstreamIfaceTypes.size()];
-        int index = 0;
-        for (Integer type : preferredUpstreamIfaceTypes) {
-            preferredTypes[index++] = type;
-        }
-        parcel.preferredUpstreamIfaceTypes = preferredTypes;
+        parcel.preferredUpstreamIfaceTypes = toIntArray(preferredUpstreamIfaceTypes);
 
         parcel.legacyDhcpRanges = legacyDhcpRanges;
         parcel.defaultIPv4DNS = defaultIPv4DNS;
diff --git a/Tethering/src/com/android/server/connectivity/tethering/TetheringInterfaceUtils.java b/Tethering/src/com/android/server/connectivity/tethering/TetheringInterfaceUtils.java
index 6334c20..d5cdd8a 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/TetheringInterfaceUtils.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/TetheringInterfaceUtils.java
@@ -22,14 +22,17 @@
 import android.net.RouteInfo;
 import android.net.util.InterfaceSet;
 
-import java.net.Inet4Address;
-import java.net.Inet6Address;
 import java.net.InetAddress;
+import java.net.UnknownHostException;
 
 /**
  * @hide
  */
 public final class TetheringInterfaceUtils {
+    private static final InetAddress IN6ADDR_ANY = getByAddress(
+            new byte[] {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0});
+    private static final InetAddress INADDR_ANY = getByAddress(new byte[] {0, 0, 0, 0});
+
     /**
      * Get upstream interfaces for tethering based on default routes for IPv4/IPv6.
      * @return null if there is no usable interface, or a set of at least one interface otherwise.
@@ -40,7 +43,7 @@
         }
 
         final LinkProperties lp = ns.linkProperties;
-        final String if4 = getInterfaceForDestination(lp, Inet4Address.ANY);
+        final String if4 = getInterfaceForDestination(lp, INADDR_ANY);
         final String if6 = getIPv6Interface(ns);
 
         return (if4 == null && if6 == null) ? null : new InterfaceSet(if4, if6);
@@ -76,7 +79,7 @@
                 && ns.networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR);
 
         return canTether
-                ? getInterfaceForDestination(ns.linkProperties, Inet6Address.ANY)
+                ? getInterfaceForDestination(ns.linkProperties, IN6ADDR_ANY)
                 : null;
     }
 
@@ -86,4 +89,12 @@
                 : null;
         return (ri != null) ? ri.getInterface() : null;
     }
+
+    private static InetAddress getByAddress(final byte[] addr) {
+        try {
+            return InetAddress.getByAddress(null, addr);
+        } catch (UnknownHostException e) {
+            throw new AssertionError("illegal address length" + addr.length);
+        }
+    }
 }
diff --git a/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java b/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java
index 775484e..e4e4a09 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java
@@ -26,11 +26,11 @@
 import android.app.Service;
 import android.content.Context;
 import android.content.Intent;
-import android.net.ConnectivityManager;
 import android.net.IIntResultListener;
 import android.net.INetworkStackConnector;
 import android.net.ITetheringConnector;
 import android.net.ITetheringEventCallback;
+import android.net.NetworkCapabilities;
 import android.net.NetworkRequest;
 import android.net.dhcp.DhcpServerCallbacks;
 import android.net.dhcp.DhcpServingParamsParcel;
@@ -307,9 +307,15 @@
             mDeps = new TetheringDependencies() {
                 @Override
                 public NetworkRequest getDefaultNetworkRequest() {
-                    ConnectivityManager cm = (ConnectivityManager) mContext.getSystemService(
-                            Context.CONNECTIVITY_SERVICE);
-                    return cm.getDefaultRequest();
+                    // TODO: b/147280869, add a proper system API to replace this.
+                    final NetworkRequest trackDefaultRequest = new NetworkRequest.Builder()
+                            .clearCapabilities()
+                            .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED)
+                            .addCapability(NetworkCapabilities.NET_CAPABILITY_TRUSTED)
+                            .addCapability(NetworkCapabilities.NET_CAPABILITY_NOT_VPN)
+                            .addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
+                            .build();
+                    return trackDefaultRequest;
                 }
 
                 @Override
diff --git a/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java b/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
index 22150f6..fe3f517 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
@@ -19,7 +19,6 @@
 import static android.net.ConnectivityManager.TYPE_MOBILE_DUN;
 import static android.net.ConnectivityManager.TYPE_MOBILE_HIPRI;
 import static android.net.ConnectivityManager.TYPE_NONE;
-import static android.net.ConnectivityManager.getNetworkTypeName;
 import static android.net.NetworkCapabilities.NET_CAPABILITY_DUN;
 import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_VPN;
 import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;
@@ -35,7 +34,6 @@
 import android.net.util.PrefixUtils;
 import android.net.util.SharedLog;
 import android.os.Handler;
-import android.os.Process;
 import android.util.Log;
 
 import com.android.internal.annotations.VisibleForTesting;
@@ -130,15 +128,15 @@
      */
     public void startTrackDefaultNetwork(NetworkRequest defaultNetworkRequest,
             EntitlementManager entitle) {
-        // This is not really a "request", just a way of tracking the system default network.
-        // It's guaranteed not to actually bring up any networks because it's the same request
-        // as the ConnectivityService default request, and thus shares fate with it. We can't
-        // use registerDefaultNetworkCallback because it will not track the system default
-        // network if there is a VPN that applies to our UID.
+
+        // defaultNetworkRequest is not really a "request", just a way of tracking the system
+        // default network. It's guaranteed not to actually bring up any networks because it's
+        // the should be the same request as the ConnectivityService default request, and thus
+        // shares fate with it. We can't use registerDefaultNetworkCallback because it will not
+        // track the system default network if there is a VPN that applies to our UID.
         if (mDefaultNetworkCallback == null) {
-            final NetworkRequest trackDefaultRequest = new NetworkRequest(defaultNetworkRequest);
             mDefaultNetworkCallback = new UpstreamNetworkCallback(CALLBACK_DEFAULT_INTERNET);
-            cm().requestNetwork(trackDefaultRequest, mDefaultNetworkCallback, mHandler);
+            cm().requestNetwork(defaultNetworkRequest, mDefaultNetworkCallback, mHandler);
         }
         if (mEntitlementMgr == null) {
             mEntitlementMgr = entitle;
@@ -239,7 +237,7 @@
         final TypeStatePair typeStatePair = findFirstAvailableUpstreamByType(
                 mNetworkMap.values(), preferredTypes, isCellularUpstreamPermitted());
 
-        mLog.log("preferred upstream type: " + getNetworkTypeName(typeStatePair.type));
+        mLog.log("preferred upstream type: " + typeStatePair.type);
 
         switch (typeStatePair.type) {
             case TYPE_MOBILE_DUN:
@@ -514,16 +512,13 @@
             try {
                 nc = ConnectivityManager.networkCapabilitiesForType(type);
             } catch (IllegalArgumentException iae) {
-                Log.e(TAG, "No NetworkCapabilities mapping for legacy type: "
-                        + ConnectivityManager.getNetworkTypeName(type));
+                Log.e(TAG, "No NetworkCapabilities mapping for legacy type: " + type);
                 continue;
             }
             if (!isCellularUpstreamPermitted && isCellular(nc)) {
                 continue;
             }
 
-            nc.setSingleUid(Process.myUid());
-
             for (UpstreamNetworkState value : netStates) {
                 if (!nc.satisfiedByNetworkCapabilities(value.networkCapabilities)) {
                     continue;