diff --git a/core/java/android/net/NetworkStateSnapshot.java b/core/java/android/net/NetworkStateSnapshot.java
index 9df861a..3915634 100644
--- a/core/java/android/net/NetworkStateSnapshot.java
+++ b/core/java/android/net/NetworkStateSnapshot.java
@@ -104,7 +104,10 @@
         return mSubscriberId;
     }
 
-    /** Get the legacy type of the network associated with this snapshot. */
+    /**
+     * Get the legacy type of the network associated with this snapshot.
+     * @return the legacy network type. See {@code ConnectivityManager#TYPE_*}.
+     */
     public int getLegacyType() {
         return mLegacyType;
     }
diff --git a/services/core/java/com/android/server/NsdService.java b/services/core/java/com/android/server/NsdService.java
index a9f3a1b..f440ee8 100644
--- a/services/core/java/com/android/server/NsdService.java
+++ b/services/core/java/com/android/server/NsdService.java
@@ -871,7 +871,7 @@
 
         @Override
         public String toString() {
-            StringBuffer sb = new StringBuffer();
+            StringBuilder sb = new StringBuilder();
             sb.append("mChannel ").append(mChannel).append("\n");
             sb.append("mMessenger ").append(mMessenger).append("\n");
             sb.append("mResolvedService ").append(mResolvedService).append("\n");
diff --git a/services/core/java/com/android/server/net/NetworkStatsAccess.java b/services/core/java/com/android/server/net/NetworkStatsAccess.java
index ddc5ef2..d25eae4 100644
--- a/services/core/java/com/android/server/net/NetworkStatsAccess.java
+++ b/services/core/java/com/android/server/net/NetworkStatsAccess.java
@@ -27,6 +27,7 @@
 import android.app.admin.DevicePolicyManagerInternal;
 import android.content.Context;
 import android.content.pm.PackageManager;
+import android.os.Binder;
 import android.os.Process;
 import android.os.UserHandle;
 import android.telephony.TelephonyManager;
@@ -108,10 +109,17 @@
                 DevicePolicyManagerInternal.class);
         final TelephonyManager tm = (TelephonyManager)
                 context.getSystemService(Context.TELEPHONY_SERVICE);
-        boolean hasCarrierPrivileges = tm != null &&
-                tm.checkCarrierPrivilegesForPackageAnyPhone(callingPackage) ==
-                        TelephonyManager.CARRIER_PRIVILEGE_STATUS_HAS_ACCESS;
-        boolean isDeviceOwner = dpmi != null && dpmi.isActiveDeviceOwner(callingUid);
+        boolean hasCarrierPrivileges;
+        final long token = Binder.clearCallingIdentity();
+        try {
+            hasCarrierPrivileges = tm != null
+                    && tm.checkCarrierPrivilegesForPackageAnyPhone(callingPackage)
+                            == TelephonyManager.CARRIER_PRIVILEGE_STATUS_HAS_ACCESS;
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+
+        final boolean isDeviceOwner = dpmi != null && dpmi.isActiveDeviceOwner(callingUid);
         final int appId = UserHandle.getAppId(callingUid);
         if (hasCarrierPrivileges || isDeviceOwner
                 || appId == Process.SYSTEM_UID || appId == Process.NETWORK_STACK_UID) {
diff --git a/services/core/java/com/android/server/net/NetworkStatsCollection.java b/services/core/java/com/android/server/net/NetworkStatsCollection.java
index 6aefe41..557fa89 100644
--- a/services/core/java/com/android/server/net/NetworkStatsCollection.java
+++ b/services/core/java/com/android/server/net/NetworkStatsCollection.java
@@ -54,6 +54,8 @@
 
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.util.ArrayUtils;
+import com.android.internal.util.FastDataInput;
+import com.android.internal.util.FastDataOutput;
 import com.android.internal.util.FileRotator;
 import com.android.internal.util.IndentingPrintWriter;
 
@@ -89,6 +91,9 @@
     /** File header magic number: "ANET" */
     private static final int FILE_MAGIC = 0x414E4554;
 
+    /** Default buffer size from BufferedInputStream */
+    private static final int BUFFER_SIZE = 8192;
+
     private static final int VERSION_NETWORK_INIT = 1;
 
     private static final int VERSION_UID_INIT = 1;
@@ -434,7 +439,8 @@
 
     @Override
     public void read(InputStream in) throws IOException {
-        read((DataInput) new DataInputStream(in));
+        final FastDataInput dataIn = new FastDataInput(in, BUFFER_SIZE);
+        read(dataIn);
     }
 
     private void read(DataInput in) throws IOException {
@@ -473,8 +479,9 @@
 
     @Override
     public void write(OutputStream out) throws IOException {
-        write((DataOutput) new DataOutputStream(out));
-        out.flush();
+        final FastDataOutput dataOut = new FastDataOutput(out, BUFFER_SIZE);
+        write(dataOut);
+        dataOut.flush();
     }
 
     private void write(DataOutput out) throws IOException {
diff --git a/services/tests/servicestests/src/com/android/server/net/IpConfigStoreTest.java b/services/tests/servicestests/src/com/android/server/net/IpConfigStoreTest.java
index 401d6e3..2f77126 100644
--- a/services/tests/servicestests/src/com/android/server/net/IpConfigStoreTest.java
+++ b/services/tests/servicestests/src/com/android/server/net/IpConfigStoreTest.java
@@ -39,6 +39,8 @@
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.net.InetAddress;
+import java.util.ArrayList;
 import java.util.Arrays;
 
 /**
@@ -53,8 +55,8 @@
         ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
         DataOutputStream outputStream = new DataOutputStream(byteStream);
 
-        IpConfiguration expectedConfig = new IpConfiguration(IpAssignment.DHCP,
-                ProxySettings.NONE, null, null);
+        final IpConfiguration expectedConfig =
+                newIpConfiguration(IpAssignment.DHCP, ProxySettings.NONE, null, null);
 
         // Emulate writing to old format.
         writeDhcpConfigV2(outputStream, KEY_CONFIG, expectedConfig);
@@ -78,18 +80,23 @@
         final String DNS_IP_ADDR_1 = "1.2.3.4";
         final String DNS_IP_ADDR_2 = "5.6.7.8";
 
-        StaticIpConfiguration staticIpConfiguration = new StaticIpConfiguration();
-        staticIpConfiguration.ipAddress = new LinkAddress(IP_ADDR_1);
-        staticIpConfiguration.dnsServers.add(InetAddresses.parseNumericAddress(DNS_IP_ADDR_1));
-        staticIpConfiguration.dnsServers.add(InetAddresses.parseNumericAddress(DNS_IP_ADDR_2));
+        final ArrayList<InetAddress> dnsServers = new ArrayList<>();
+        dnsServers.add(InetAddresses.parseNumericAddress(DNS_IP_ADDR_1));
+        dnsServers.add(InetAddresses.parseNumericAddress(DNS_IP_ADDR_2));
+        final StaticIpConfiguration staticIpConfiguration1 = new StaticIpConfiguration.Builder()
+                .setIpAddress(new LinkAddress(IP_ADDR_1))
+                .setDnsServers(dnsServers).build();
+        final StaticIpConfiguration staticIpConfiguration2 = new StaticIpConfiguration.Builder()
+                .setIpAddress(new LinkAddress(IP_ADDR_2))
+                .setDnsServers(dnsServers).build();
 
         ProxyInfo proxyInfo =
                 ProxyInfo.buildDirectProxy("10.10.10.10", 88, Arrays.asList("host1", "host2"));
 
-        IpConfiguration expectedConfig1 = new IpConfiguration(IpAssignment.STATIC,
-                ProxySettings.STATIC, staticIpConfiguration, proxyInfo);
-        IpConfiguration expectedConfig2 = new IpConfiguration(expectedConfig1);
-        expectedConfig2.getStaticIpConfiguration().ipAddress = new LinkAddress(IP_ADDR_2);
+        IpConfiguration expectedConfig1 = newIpConfiguration(IpAssignment.STATIC,
+                ProxySettings.STATIC, staticIpConfiguration1, proxyInfo);
+        IpConfiguration expectedConfig2 = newIpConfiguration(IpAssignment.STATIC,
+                ProxySettings.STATIC, staticIpConfiguration2, proxyInfo);
 
         ArrayMap<String, IpConfiguration> expectedNetworks = new ArrayMap<>();
         expectedNetworks.put(IFACE_1, expectedConfig1);
@@ -107,14 +114,24 @@
         assertEquals(expectedNetworks.get(IFACE_2), actualNetworks.get(IFACE_2));
     }
 
+    private IpConfiguration newIpConfiguration(IpAssignment ipAssignment,
+            ProxySettings proxySettings, StaticIpConfiguration staticIpConfig, ProxyInfo info) {
+        final IpConfiguration config = new IpConfiguration();
+        config.setIpAssignment(ipAssignment);
+        config.setProxySettings(proxySettings);
+        config.setStaticIpConfiguration(staticIpConfig);
+        config.setHttpProxy(info);
+        return config;
+    }
+
     // This is simplified snapshot of code that was used to store values in V2 format (key as int).
     private static void writeDhcpConfigV2(DataOutputStream out, int configKey,
             IpConfiguration config) throws IOException {
         out.writeInt(2);  // VERSION 2
-        switch (config.ipAssignment) {
+        switch (config.getIpAssignment()) {
             case DHCP:
                 out.writeUTF("ipAssignment");
-                out.writeUTF(config.ipAssignment.toString());
+                out.writeUTF(config.getIpAssignment().toString());
                 break;
             default:
                 fail("Not supported in test environment");