ScanRequestProxy: Clear scan request timestamps on app removal

Ensure we cleanup any scan request timestamps stored on removal of the
app.
Note: Apps have the same package name across multiple users, but they
have different UID's allocated. So, modify the timestamps cache in
ScanRequestProxy to store both the package name and the uid.

Bug: 77588735
Test: Manually Verified app removal cleans up the throttling timestamps
(using the Android power team's scan app)
Test: Unit tests

Change-Id: I7d82d7a742ac4d0ec299adca115648f8786f96ae

2 files changed, 34 insertions, 7 deletions

diff --git a/service/java/com/android/server/wifi/ScanRequestProxy.java b/service/java/com/android/server/wifi/ScanRequestProxy.java
index b9e48ea56..d9071bd83 100644
--- a/service/java/com/android/server/wifi/ScanRequestProxy.java
+++ b/service/java/com/android/server/wifi/ScanRequestProxy.java
@@ -16,6 +16,7 @@
 
 package com.android.server.wifi;
 
+import android.annotation.NonNull;
 import android.app.ActivityManager;
 import android.app.AppOpsManager;
 import android.content.Context;
@@ -28,6 +29,7 @@ import android.os.UserHandle;
 import android.os.WorkSource;
 import android.util.ArrayMap;
 import android.util.Log;
+import android.util.Pair;
 
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.server.wifi.util.WifiPermissionsUtil;
@@ -90,7 +92,10 @@ public class ScanRequestProxy {
     // Timestamps for the last scan requested by any background app.
     private long mLastScanTimestampForBgApps = 0;
     // Timestamps for the list of last few scan requests by each foreground app.
-    private final ArrayMap<String, LinkedList<Long>> mLastScanTimestampsForFgApps = new ArrayMap();
+    // Keys in the map = Pair<Uid, PackageName> of the app.
+    // Values in the map = List of the last few scan request timestamps from the app.
+    private final ArrayMap<Pair<Integer, String>, LinkedList<Long>> mLastScanTimestampsForFgApps =
+            new ArrayMap();
     // Scan results cached from the last full single scan request.
     private final List<ScanResult> mLastScanResults = new ArrayList<>();
     // Common scan listener for scan requests.
@@ -246,11 +251,14 @@ public class ScanRequestProxy {
         }
     }
 
-    private LinkedList<Long> getOrCreateScanRequestTimestampsForForegroundApp(String packageName) {
-        LinkedList<Long> scanRequestTimestamps = mLastScanTimestampsForFgApps.get(packageName);
+    private LinkedList<Long> getOrCreateScanRequestTimestampsForForegroundApp(
+            int callingUid, String packageName) {
+        Pair<Integer, String> uidAndPackageNamePair = Pair.create(callingUid, packageName);
+        LinkedList<Long> scanRequestTimestamps =
+                mLastScanTimestampsForFgApps.get(uidAndPackageNamePair);
         if (scanRequestTimestamps == null) {
             scanRequestTimestamps = new LinkedList<>();
-            mLastScanTimestampsForFgApps.put(packageName, scanRequestTimestamps);
+            mLastScanTimestampsForFgApps.put(uidAndPackageNamePair, scanRequestTimestamps);
         }
         return scanRequestTimestamps;
     }
@@ -261,9 +269,10 @@ public class ScanRequestProxy {
      * The throttle limit allows a max of {@link #SCAN_REQUEST_THROTTLE_MAX_IN_TIME_WINDOW_FG_APPS}
      * in {@link #SCAN_REQUEST_THROTTLE_TIME_WINDOW_FG_APPS_MS} window.
      */
-    private boolean shouldScanRequestBeThrottledForForegroundApp(String packageName) {
+    private boolean shouldScanRequestBeThrottledForForegroundApp(
+            int callingUid, String packageName) {
         LinkedList<Long> scanRequestTimestamps =
-                getOrCreateScanRequestTimestampsForForegroundApp(packageName);
+                getOrCreateScanRequestTimestampsForForegroundApp(callingUid, packageName);
         long currentTimeMillis = mClock.getElapsedSinceBootMillis();
         // First evict old entries from the list.
         trimPastScanRequestTimesForForegroundApp(scanRequestTimestamps, currentTimeMillis);
@@ -324,7 +333,7 @@ public class ScanRequestProxy {
                 mWifiMetrics.incrementExternalBackgroundAppOneshotScanRequestsThrottledCount();
             }
         } else {
-            isThrottled = shouldScanRequestBeThrottledForForegroundApp(packageName);
+            isThrottled = shouldScanRequestBeThrottledForForegroundApp(callingUid, packageName);
             if (isThrottled) {
                 if (mVerboseLoggingEnabled) {
                     Log.v(TAG, "Foreground scan app request [" + callingUid + ", "
@@ -398,4 +407,18 @@ public class ScanRequestProxy {
         mLastScanTimestampForBgApps = 0;
         mLastScanTimestampsForFgApps.clear();
     }
+
+    /**
+     * Clear any scan timestamps being stored for the app.
+     *
+     * @param uid Uid of the package.
+     * @param packageName Name of the package.
+     */
+    public void clearScanRequestTimestampsForApp(@NonNull String packageName, int uid) {
+        if (mVerboseLoggingEnabled) {
+            Log.v(TAG, "Clearing scan request timestamps for uid=" + uid + ", packageName="
+                    + packageName);
+        }
+        mLastScanTimestampsForFgApps.remove(Pair.create(uid, packageName));
+    }
 }
diff --git a/service/java/com/android/server/wifi/WifiServiceImpl.java b/service/java/com/android/server/wifi/WifiServiceImpl.java
index cb3628b98..3f566c355 100644
--- a/service/java/com/android/server/wifi/WifiServiceImpl.java
+++ b/service/java/com/android/server/wifi/WifiServiceImpl.java
@@ -2449,6 +2449,10 @@ public class WifiServiceImpl extends IWifiManager.Stub {
                     }
                     String pkgName = uri.getSchemeSpecificPart();
                     mWifiStateMachine.removeAppConfigs(pkgName, uid);
+                    // Call the method in WSM thread.
+                    mWifiStateMachineHandler.post(() -> {
+                        mScanRequestProxy.clearScanRequestTimestampsForApp(pkgName, uid);
+                    });
                 }
             }
         }, intentFilter);