Ensure autoKi is not stored when keepalive stops or is not started. am: ae317095ec

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/23668883

Change-Id: I51da0af248afcc983c8b581fb8468363c87d78da
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/service/src/com/android/server/connectivity/AutomaticOnOffKeepaliveTracker.java b/service/src/com/android/server/connectivity/AutomaticOnOffKeepaliveTracker.java
index e2ef981..3153b20 100644
--- a/service/src/com/android/server/connectivity/AutomaticOnOffKeepaliveTracker.java
+++ b/service/src/com/android/server/connectivity/AutomaticOnOffKeepaliveTracker.java
@@ -18,6 +18,7 @@
 
 import static android.net.SocketKeepalive.ERROR_INVALID_SOCKET;
 import static android.net.SocketKeepalive.MIN_INTERVAL_SEC;
+import static android.net.SocketKeepalive.SUCCESS;
 import static android.net.SocketKeepalive.SUCCESS_PAUSED;
 import static android.provider.DeviceConfig.NAMESPACE_TETHERING;
 import static android.system.OsConstants.AF_INET;
@@ -52,6 +53,7 @@
 import android.system.StructTimeval;
 import android.util.LocalLog;
 import android.util.Log;
+import android.util.Pair;
 import android.util.SparseArray;
 
 import com.android.internal.annotations.VisibleForTesting;
@@ -377,7 +379,11 @@
             return;
         }
         autoKi.mAutomaticOnOffState = STATE_ENABLED;
-        handleResumeKeepalive(newKi);
+        final int error = handleResumeKeepalive(newKi);
+        if (error != SUCCESS) {
+            // Failed to start the keepalive
+            cleanupAutoOnOffKeepalive(autoKi);
+        }
     }
 
     /**
@@ -398,7 +404,20 @@
      * Forward to KeepaliveTracker.
      */
     public void handleEventSocketKeepalive(@NonNull NetworkAgentInfo nai, int slot, int reason) {
-        mKeepaliveTracker.handleEventSocketKeepalive(nai, slot, reason);
+        if (mKeepaliveTracker.handleEventSocketKeepalive(nai, slot, reason)) return;
+
+        // The keepalive was stopped and so the autoKi should be cleaned up.
+        final AutomaticOnOffKeepalive autoKi =
+                CollectionUtils.findFirst(
+                        mAutomaticOnOffKeepalives, it -> it.match(nai.network(), slot));
+        if (autoKi == null) {
+            // This may occur when the autoKi gets cleaned up elsewhere (i.e
+            // handleCheckKeepalivesStillValid) while waiting for the network agent to
+            // start the keepalive and the network agent returns an error event.
+            Log.e(TAG, "Attempt cleanup on unknown network, slot");
+            return;
+        }
+        cleanupAutoOnOffKeepalive(autoKi);
     }
 
     /**
@@ -421,9 +440,14 @@
      */
     public void handleStartKeepalive(Message message) {
         final AutomaticOnOffKeepalive autoKi = (AutomaticOnOffKeepalive) message.obj;
+        final int error = mKeepaliveTracker.handleStartKeepalive(autoKi.mKi);
+        if (error != SUCCESS) {
+            mEventLog.log("Failed to start keepalive " + autoKi.mCallback + " on "
+                    + autoKi.getNetwork() + " with error " + error);
+            return;
+        }
         mEventLog.log("Start keepalive " + autoKi.mCallback + " on " + autoKi.getNetwork());
         mKeepaliveStatsTracker.onStartKeepalive();
-        mKeepaliveTracker.handleStartKeepalive(autoKi.mKi);
 
         // Add automatic on/off request into list to track its life cycle.
         try {
@@ -439,10 +463,22 @@
         }
     }
 
-    private void handleResumeKeepalive(@NonNull final KeepaliveTracker.KeepaliveInfo ki) {
+    /**
+     * Handle resume keepalive with the given KeepaliveInfo
+     *
+     * @return SUCCESS if the keepalive is successfully starting and the error reason otherwise.
+     */
+    private int handleResumeKeepalive(@NonNull final KeepaliveTracker.KeepaliveInfo ki) {
+        final int error = mKeepaliveTracker.handleStartKeepalive(ki);
+        if (error != SUCCESS) {
+            mEventLog.log("Failed to resume keepalive " + ki.mCallback + " on " + ki.mNai
+                    + " with error " + error);
+            return error;
+        }
         mKeepaliveStatsTracker.onResumeKeepalive();
-        mKeepaliveTracker.handleStartKeepalive(ki);
         mEventLog.log("Resumed successfully keepalive " + ki.mCallback + " on " + ki.mNai);
+
+        return SUCCESS;
     }
 
     private void handlePauseKeepalive(@NonNull final KeepaliveTracker.KeepaliveInfo ki) {
@@ -604,7 +640,22 @@
      * Forward to KeepaliveTracker.
      */
     public void handleCheckKeepalivesStillValid(NetworkAgentInfo nai) {
-        mKeepaliveTracker.handleCheckKeepalivesStillValid(nai);
+        ArrayList<Pair<AutomaticOnOffKeepalive, Integer>> invalidKeepalives = null;
+
+        for (final AutomaticOnOffKeepalive autoKi : mAutomaticOnOffKeepalives) {
+            if (!nai.equals(autoKi.mKi.mNai)) continue;
+            final int error = autoKi.mKi.isValid();
+            if (error != SUCCESS) {
+                if (invalidKeepalives == null) {
+                    invalidKeepalives = new ArrayList<>();
+                }
+                invalidKeepalives.add(Pair.create(autoKi, error));
+            }
+        }
+        if (invalidKeepalives == null) return;
+        for (final Pair<AutomaticOnOffKeepalive, Integer> keepaliveAndError : invalidKeepalives) {
+            handleStopKeepalive(keepaliveAndError.first, keepaliveAndError.second);
+        }
     }
 
     @VisibleForTesting
diff --git a/service/src/com/android/server/connectivity/KeepaliveTracker.java b/service/src/com/android/server/connectivity/KeepaliveTracker.java
index cc226ce..409b188 100644
--- a/service/src/com/android/server/connectivity/KeepaliveTracker.java
+++ b/service/src/com/android/server/connectivity/KeepaliveTracker.java
@@ -54,7 +54,6 @@
 import android.system.ErrnoException;
 import android.system.Os;
 import android.util.Log;
-import android.util.Pair;
 
 import com.android.connectivity.resources.R;
 import com.android.internal.annotations.VisibleForTesting;
@@ -337,7 +336,12 @@
             return SUCCESS;
         }
 
-        private int isValid() {
+        /**
+         * Checks if the keepalive info is valid to start.
+         *
+         * @return SUCCESS if the keepalive is valid and the error reason otherwise.
+         */
+        public int isValid() {
             synchronized (mNai) {
                 int error = checkInterval();
                 if (error == SUCCESS) error = checkLimit();
@@ -348,11 +352,17 @@
             }
         }
 
-        void start(int slot) {
+        /**
+         * Attempt to start the keepalive on the given slot.
+         *
+         * @param slot the slot to start the keepalive on.
+         * @return SUCCESS if the keepalive is successfully starting and the error reason otherwise.
+         */
+        int start(int slot) {
             // BINDER_DIED can happen if the binder died before the KeepaliveInfo was created and
             // the constructor set the state to BINDER_DIED. If that's the case, the KI is already
             // cleaned up.
-            if (BINDER_DIED == mStartedState) return;
+            if (BINDER_DIED == mStartedState) return BINDER_DIED;
             mSlot = slot;
             int error = isValid();
             if (error == SUCCESS) {
@@ -368,7 +378,7 @@
                             mTcpController.startSocketMonitor(mFd, this, mSlot);
                         } catch (InvalidSocketException e) {
                             handleStopKeepalive(mNai, mSlot, ERROR_INVALID_SOCKET);
-                            return;
+                            return ERROR_INVALID_SOCKET;
                         }
                         final TcpKeepalivePacketData tcpData = (TcpKeepalivePacketData) mPacket;
                         mNai.onAddTcpKeepalivePacketFilter(slot, tcpData);
@@ -377,13 +387,14 @@
                         break;
                     default:
                         Log.wtf(TAG, "Starting keepalive with unknown type: " + mType);
-                        handleStopKeepalive(mNai, mSlot, error);
-                        return;
+                        handleStopKeepalive(mNai, mSlot, ERROR_UNSUPPORTED);
+                        return ERROR_UNSUPPORTED;
                 }
                 mStartedState = STARTING;
+                return SUCCESS;
             } else {
                 handleStopKeepalive(mNai, mSlot, error);
-                return;
+                return error;
             }
         }
 
@@ -444,6 +455,8 @@
             }
         }
 
+        // TODO: This does not clean up the autoKi in AutomaticOnOffKeepaliveTracker and it is not
+        // possible without a big refactor.
         void onFileDescriptorInitiatedStop(final int socketKeepaliveReason) {
             handleStopKeepalive(mNai, mSlot, socketKeepaliveReason);
         }
@@ -486,12 +499,15 @@
 
     /**
      * Handle start keepalives with the message.
+     *
+     * @param ki the keepalive to start.
+     * @return SUCCESS if the keepalive is successfully starting and the error reason otherwise.
      */
-    public void handleStartKeepalive(KeepaliveInfo ki) {
+    public int handleStartKeepalive(KeepaliveInfo ki) {
         NetworkAgentInfo nai = ki.getNai();
         int slot = findFirstFreeSlot(nai);
         mKeepalives.get(nai).put(slot, ki);
-        ki.start(slot);
+        return ki.start(slot);
     }
 
     public void handleStopAllKeepalives(NetworkAgentInfo nai, int reason) {
@@ -609,24 +625,13 @@
         }
     }
 
-    public void handleCheckKeepalivesStillValid(NetworkAgentInfo nai) {
-        HashMap <Integer, KeepaliveInfo> networkKeepalives = mKeepalives.get(nai);
-        if (networkKeepalives != null) {
-            ArrayList<Pair<Integer, Integer>> invalidKeepalives = new ArrayList<>();
-            for (int slot : networkKeepalives.keySet()) {
-                int error = networkKeepalives.get(slot).isValid();
-                if (error != SUCCESS) {
-                    invalidKeepalives.add(Pair.create(slot, error));
-                }
-            }
-            for (Pair<Integer, Integer> slotAndError: invalidKeepalives) {
-                handleStopKeepalive(nai, slotAndError.first, slotAndError.second);
-            }
-        }
-    }
-
-    /** Handle keepalive events from lower layer. */
-    public void handleEventSocketKeepalive(@NonNull NetworkAgentInfo nai, int slot, int reason) {
+    /**
+     * Handle keepalive events from lower layer.
+     *
+     * @return false if the event caused handleStopKeepalive to be called, i.e. the keepalive is
+     *     forced to stop. Otherwise, return true.
+     */
+    public boolean handleEventSocketKeepalive(@NonNull NetworkAgentInfo nai, int slot, int reason) {
         KeepaliveInfo ki = null;
         try {
             ki = mKeepalives.get(nai).get(slot);
@@ -634,7 +639,7 @@
         if (ki == null) {
             Log.e(TAG, "Event " + NetworkAgent.EVENT_SOCKET_KEEPALIVE + "," + slot + "," + reason
                     + " for unknown keepalive " + slot + " on " + nai.toShortString());
-            return;
+            return true;
         }
 
         // This can be called in a number of situations :
@@ -667,11 +672,13 @@
                     Log.w(TAG, "Discarded " + (ki.mResumed ? "onResumed" : "onStarted")
                             + " callback for slot " + slot);
                 }
+                return true;
             } else {
                 Log.d(TAG, "Failed to start keepalive " + slot + " on " + nai.toShortString()
                         + ": " + reason);
                 // The message indicated some error trying to start: do call handleStopKeepalive.
                 handleStopKeepalive(nai, slot, reason);
+                return false;
             }
         } else if (KeepaliveInfo.STOPPING == ki.mStartedState) {
             // The message indicated result of stopping : clean up keepalive slots.
@@ -679,9 +686,12 @@
                     + " stopped: " + reason);
             ki.mStartedState = KeepaliveInfo.NOT_STARTED;
             cleanupStoppedKeepalive(nai, slot);
+            return true;
         } else {
             Log.wtf(TAG, "Event " + NetworkAgent.EVENT_SOCKET_KEEPALIVE + "," + slot + "," + reason
                     + " for keepalive in wrong state: " + ki.toString());
+            // Although this is an unexpected event, the keepalive is not stopped here.
+            return true;
         }
     }
 
diff --git a/tests/unit/java/com/android/server/connectivity/AutomaticOnOffKeepaliveTrackerTest.java b/tests/unit/java/com/android/server/connectivity/AutomaticOnOffKeepaliveTrackerTest.java
index d0b0ac4..946df07 100644
--- a/tests/unit/java/com/android/server/connectivity/AutomaticOnOffKeepaliveTrackerTest.java
+++ b/tests/unit/java/com/android/server/connectivity/AutomaticOnOffKeepaliveTrackerTest.java
@@ -25,6 +25,7 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
@@ -491,8 +492,7 @@
         final TestKeepaliveInfo testInfo =
                 doStartNattKeepalive(TEST_KEEPALIVE_INVALID_INTERVAL_SEC);
 
-        // TODO: Should be null, no keepalive should be stored.
-        assertNotNull(getAutoKiForBinder(testInfo.binder));
+        assertNull(getAutoKiForBinder(testInfo.binder));
 
         verify(testInfo.socketKeepaliveCallback).onError(SocketKeepalive.ERROR_INVALID_INTERVAL);
         verifyNoMoreInteractions(ignoreStubs(testInfo.socketKeepaliveCallback));
@@ -510,8 +510,7 @@
 
         checkAndProcessKeepaliveStop();
 
-        // TODO: Should be null, should cleanup on starting failure.
-        assertNotNull(getAutoKiForBinder(testInfo.binder));
+        assertNull(getAutoKiForBinder(testInfo.binder));
 
         verify(testInfo.socketKeepaliveCallback).onError(SocketKeepalive.ERROR_HARDWARE_ERROR);
         verifyNoMoreInteractions(ignoreStubs(testInfo.socketKeepaliveCallback));
@@ -534,8 +533,7 @@
 
         checkAndProcessKeepaliveStop();
 
-        // TODO: Should be null, keepalives that are no longer valid should be cleaned up.
-        assertNotNull(getAutoKiForBinder(testInfo.binder));
+        assertNull(getAutoKiForBinder(testInfo.binder));
 
         verify(testInfo.socketKeepaliveCallback).onError(SocketKeepalive.ERROR_INVALID_IP_ADDRESS);
         verifyNoMoreInteractions(ignoreStubs(testInfo.socketKeepaliveCallback));