diff --git a/framework-t/src/android/net/NetworkStatsAccess.java b/framework-t/src/android/net/NetworkStatsAccess.java
index 23902dc..7fe499b 100644
--- a/framework-t/src/android/net/NetworkStatsAccess.java
+++ b/framework-t/src/android/net/NetworkStatsAccess.java
@@ -23,6 +23,7 @@
 
 import android.Manifest;
 import android.annotation.IntDef;
+import android.annotation.Nullable;
 import android.app.AppOpsManager;
 import android.app.admin.DevicePolicyManager;
 import android.content.Context;
@@ -109,7 +110,7 @@
 
     /** Returns the {@link NetworkStatsAccess.Level} for the given caller. */
     public static @NetworkStatsAccess.Level int checkAccessLevel(
-            Context context, int callingPid, int callingUid, String callingPackage) {
+            Context context, int callingPid, int callingUid, @Nullable String callingPackage) {
         final DevicePolicyManager mDpm = context.getSystemService(DevicePolicyManager.class);
         final TelephonyManager tm = (TelephonyManager)
                 context.getSystemService(Context.TELEPHONY_SERVICE);
diff --git a/service-t/src/com/android/server/net/NetworkStatsService.java b/service-t/src/com/android/server/net/NetworkStatsService.java
index eb75461..7cf6293 100644
--- a/service-t/src/com/android/server/net/NetworkStatsService.java
+++ b/service-t/src/com/android/server/net/NetworkStatsService.java
@@ -492,9 +492,10 @@
      */
     private static class OpenSessionKey {
         public final int uid;
+        @Nullable
         public final String packageName;
 
-        OpenSessionKey(int uid, @NonNull String packageName) {
+        OpenSessionKey(int uid, @Nullable String packageName) {
             this.uid = uid;
             this.packageName = packageName;
         }
@@ -1461,7 +1462,7 @@
         return now - lastCallTime < POLL_RATE_LIMIT_MS;
     }
 
-    private int restrictFlagsForCaller(int flags, @NonNull String callingPackage) {
+    private int restrictFlagsForCaller(int flags, @Nullable String callingPackage) {
         // All non-privileged callers are not allowed to turn off POLL_ON_OPEN.
         final boolean isPrivileged = PermissionUtils.checkAnyPermissionOf(mContext,
                 NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
@@ -1478,7 +1479,8 @@
         return flags;
     }
 
-    private INetworkStatsSession openSessionInternal(final int flags, final String callingPackage) {
+    private INetworkStatsSession openSessionInternal(
+            final int flags, @Nullable final String callingPackage) {
         final int restrictedFlags = restrictFlagsForCaller(flags, callingPackage);
         if ((restrictedFlags & (NetworkStatsManager.FLAG_POLL_ON_OPEN
                 | NetworkStatsManager.FLAG_POLL_FORCE)) != 0) {
@@ -1495,6 +1497,7 @@
 
         return new INetworkStatsSession.Stub() {
             private final int mCallingUid = Binder.getCallingUid();
+            @Nullable
             private final String mCallingPackage = callingPackage;
             private final @NetworkStatsAccess.Level int mAccessLevel = checkAccessLevel(
                     callingPackage);
@@ -1633,7 +1636,7 @@
     }
 
     private void enforceTemplatePermissions(@NonNull NetworkTemplate template,
-            @NonNull String callingPackage) {
+            @Nullable String callingPackage) {
         // For a template with wifi network keys, it is possible for a malicious
         // client to track the user locations via querying data usage. Thus, enforce
         // fine location permission check.
@@ -1654,7 +1657,7 @@
         }
     }
 
-    private @NetworkStatsAccess.Level int checkAccessLevel(String callingPackage) {
+    private @NetworkStatsAccess.Level int checkAccessLevel(@Nullable String callingPackage) {
         return NetworkStatsAccess.checkAccessLevel(
                 mContext, Binder.getCallingPid(), Binder.getCallingUid(), callingPackage);
     }
diff --git a/staticlibs/framework/com/android/net/module/util/LocationPermissionChecker.java b/staticlibs/framework/com/android/net/module/util/LocationPermissionChecker.java
index cd1f31c..f6bee69 100644
--- a/staticlibs/framework/com/android/net/module/util/LocationPermissionChecker.java
+++ b/staticlibs/framework/com/android/net/module/util/LocationPermissionChecker.java
@@ -189,8 +189,9 @@
      * @param message A message describing why the permission was checked. Only needed if this is
      *                not inside of a two-way binder call from the data receiver
      */
-    public boolean checkCallersLocationPermission(String pkgName, @Nullable String featureId,
-            int uid, boolean coarseForTargetSdkLessThanQ, @Nullable String message) {
+    public boolean checkCallersLocationPermission(@Nullable String pkgName,
+            @Nullable String featureId, int uid, boolean coarseForTargetSdkLessThanQ,
+            @Nullable String message) {
 
         boolean isTargetSdkLessThanQ = isTargetSdkLessThan(pkgName, Build.VERSION_CODES.Q, uid);