diff --git a/src/com/android/phone/LocationAccessPolicy.java b/src/com/android/phone/LocationAccessPolicy.java
new file mode 100644
index 0000000..6f2a5ec
--- /dev/null
+++ b/src/com/android/phone/LocationAccessPolicy.java
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.phone;
+
+import android.Manifest;
+import android.annotation.NonNull;
+import android.annotation.UserIdInt;
+import android.app.ActivityManager;
+import android.app.AppOpsManager;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.content.pm.UserInfo;
+import android.os.Build;
+import android.os.UserHandle;
+import android.os.UserManager;
+import android.provider.Settings;
+
+import java.util.List;
+
+/**
+ * Helper for performing location access checks.
+ */
+final class LocationAccessPolicy {
+
+    private LocationAccessPolicy() {
+        /* do nothing - hide ctor */
+    }
+
+    /**
+     * API to determine if the caller has permissions to get cell location.
+     *
+     * @param pkgName Package name of the application requesting access
+     * @param uid The uid of the package
+     * @param message Message to add to the exception if no location permission
+     * @return boolean true or false if permissions is granted
+     */
+    static boolean canAccessCellLocation(@NonNull Context context, @NonNull String pkgName,
+            int uid, String message) throws SecurityException {
+        context.getSystemService(AppOpsManager.class).checkPackage(uid, pkgName);
+        // We always require the location permission and also require the
+        // location mode to be on for non-legacy apps. Legacy apps are
+        // required to be in the foreground to at least mitigate the case
+        // where a legacy app the user is not using tracks their location.
+
+        // Grating ACCESS_FINE_LOCATION to an app automatically grants it ACCESS_COARSE_LOCATION.
+        context.enforceCallingOrSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION, message);
+        final int opCode = AppOpsManager.permissionToOpCode(
+                Manifest.permission.ACCESS_COARSE_LOCATION);
+        if (opCode != AppOpsManager.OP_NONE && context.getSystemService(AppOpsManager.class)
+                .noteOp(opCode, uid, pkgName) != AppOpsManager.MODE_ALLOWED) {
+            return false;
+        }
+        if (!isLocationModeEnabled(context, UserHandle.getUserId(uid))
+                && !isLegacyForeground(context, pkgName)) {
+            return false;
+        }
+        // If the user or profile is current, permission is granted.
+        // Otherwise, uid must have INTERACT_ACROSS_USERS_FULL permission.
+        return isCurrentProfile(context, uid) || checkInteractAcrossUsersFull(context);
+    }
+
+    private static boolean isLocationModeEnabled(@NonNull Context context, @UserIdInt int userId) {
+        return Settings.Secure.getIntForUser(context.getContentResolver(),
+                Settings.Secure.LOCATION_MODE, Settings.Secure.LOCATION_MODE_OFF, userId)
+                != Settings.Secure.LOCATION_MODE_OFF;
+    }
+
+    private static boolean isLegacyForeground(@NonNull Context context, @NonNull String pkgName) {
+        return isLegacyVersion(context, pkgName) && isForegroundApp(context, pkgName);
+    }
+
+    private static boolean isLegacyVersion(@NonNull Context context, @NonNull String pkgName) {
+        try {
+            if (context.getPackageManager().getApplicationInfo(pkgName, 0)
+                    .targetSdkVersion <= Build.VERSION_CODES.O) {
+                return true;
+            }
+        } catch (PackageManager.NameNotFoundException e) {
+            // In case of exception, assume known app (more strict checking)
+            // Note: This case will never happen since checkPackage is
+            // called to verify validity before checking app's version.
+        }
+        return false;
+    }
+
+    private static boolean isForegroundApp(@NonNull Context context, @NonNull String pkgName) {
+        final ActivityManager am = context.getSystemService(ActivityManager.class);
+        final List<ActivityManager.RunningTaskInfo> tasks = am.getRunningTasks(1);
+        if (!tasks.isEmpty()) {
+            return pkgName.equals(tasks.get(0).topActivity.getPackageName());
+        }
+        return false;
+    }
+
+    private static boolean checkInteractAcrossUsersFull(@NonNull Context context) {
+        return context.checkCallingOrSelfPermission(
+                android.Manifest.permission.INTERACT_ACROSS_USERS_FULL)
+                == PackageManager.PERMISSION_GRANTED;
+    }
+
+    private static boolean isCurrentProfile(@NonNull Context context, int uid) {
+        final int currentUser = ActivityManager.getCurrentUser();
+        final int callingUserId = UserHandle.getUserId(uid);
+        if (callingUserId == currentUser) {
+            return true;
+        } else {
+            List<UserInfo> userProfiles = context.getSystemService(
+                    UserManager.class).getProfiles(currentUser);
+            for (UserInfo user: userProfiles) {
+                if (user.id == callingUserId) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+}
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index 4933ed8..253c5f9 100644
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -55,7 +55,6 @@
 import android.telephony.CellInfo;
 import android.telephony.ClientRequestStats;
 import android.telephony.IccOpenLogicalChannelResponse;
-import android.telephony.LocationAccessPolicy;
 import android.telephony.ModemActivityInfo;
 import android.telephony.NeighboringCellInfo;
 import android.telephony.NetworkScanRequest;
@@ -1653,10 +1652,8 @@
 
     @Override
     public Bundle getCellLocation(String callingPackage) {
-        mPhone.getContext().getSystemService(AppOpsManager.class)
-                .checkPackage(Binder.getCallingUid(), callingPackage);
         if (!LocationAccessPolicy.canAccessCellLocation(mPhone.getContext(),
-                callingPackage, Binder.getCallingUid(),Binder.getCallingPid())) {
+                callingPackage, Binder.getCallingUid(), "getCellLocation")) {
             return null;
         }
 
@@ -1723,10 +1720,8 @@
     @Override
     @SuppressWarnings("unchecked")
     public List<NeighboringCellInfo> getNeighboringCellInfo(String callingPackage) {
-        mPhone.getContext().getSystemService(AppOpsManager.class)
-                .checkPackage(Binder.getCallingUid(), callingPackage);
         if (!LocationAccessPolicy.canAccessCellLocation(mPhone.getContext(),
-                callingPackage, Binder.getCallingUid(), Binder.getCallingPid())) {
+                callingPackage, Binder.getCallingUid(), "getNeighboringCellInfo")) {
             return null;
         }
 
@@ -1753,10 +1748,8 @@
 
     @Override
     public List<CellInfo> getAllCellInfo(String callingPackage) {
-        mPhone.getContext().getSystemService(AppOpsManager.class)
-                .checkPackage(Binder.getCallingUid(), callingPackage);
         if (!LocationAccessPolicy.canAccessCellLocation(mPhone.getContext(),
-                callingPackage, Binder.getCallingUid(), Binder.getCallingPid())) {
+                callingPackage, Binder.getCallingUid(), "getAllCellInfo")) {
             return null;
         }