Merge "Fix VcnConfig garbage collection" into main
diff --git a/core/java/android/net/vcn/flags.aconfig b/core/java/android/net/vcn/flags.aconfig
index 5b30624..3d4401b 100644
--- a/core/java/android/net/vcn/flags.aconfig
+++ b/core/java/android/net/vcn/flags.aconfig
@@ -14,4 +14,14 @@
     namespace: "vcn"
     description: "Feature flag for adjustable safe mode timeout"
     bug: "317406085"
+}
+
+flag {
+    name: "fix_config_garbage_collection"
+    namespace: "vcn"
+    description: "Handle race condition in subscription change"
+    bug: "370862489"
+    metadata {
+      purpose: PURPOSE_BUGFIX
+    }
 }
\ No newline at end of file
diff --git a/services/core/java/com/android/server/VcnManagementService.java b/services/core/java/com/android/server/VcnManagementService.java
index 51c768b..dc7749c 100644
--- a/services/core/java/com/android/server/VcnManagementService.java
+++ b/services/core/java/com/android/server/VcnManagementService.java
@@ -48,6 +48,7 @@
 import android.net.Network;
 import android.net.NetworkCapabilities;
 import android.net.NetworkRequest;
+import android.net.vcn.Flags;
 import android.net.vcn.IVcnManagementService;
 import android.net.vcn.IVcnStatusCallback;
 import android.net.vcn.IVcnUnderlyingNetworkPolicyListener;
@@ -878,6 +879,7 @@
 
     private void garbageCollectAndWriteVcnConfigsLocked() {
         final SubscriptionManager subMgr = mContext.getSystemService(SubscriptionManager.class);
+        final Set<ParcelUuid> subGroups = mLastSnapshot.getAllSubscriptionGroups();
 
         boolean shouldWrite = false;
 
@@ -885,11 +887,20 @@
         while (configsIterator.hasNext()) {
             final ParcelUuid subGrp = configsIterator.next();
 
-            final List<SubscriptionInfo> subscriptions = subMgr.getSubscriptionsInGroup(subGrp);
-            if (subscriptions == null || subscriptions.isEmpty()) {
-                // Trim subGrps with no more subscriptions; must have moved to another subGrp
-                configsIterator.remove();
-                shouldWrite = true;
+            if (Flags.fixConfigGarbageCollection()) {
+                if (!subGroups.contains(subGrp)) {
+                    // Trim subGrps with no more subscriptions; must have moved to another subGrp
+                    logDbg("Garbage collect VcnConfig for group=" + subGrp);
+                    configsIterator.remove();
+                    shouldWrite = true;
+                }
+            } else {
+                final List<SubscriptionInfo> subscriptions = subMgr.getSubscriptionsInGroup(subGrp);
+                if (subscriptions == null || subscriptions.isEmpty()) {
+                    // Trim subGrps with no more subscriptions; must have moved to another subGrp
+                    configsIterator.remove();
+                    shouldWrite = true;
+                }
             }
         }
 
@@ -1094,13 +1105,7 @@
             synchronized (mLock) {
                 final Vcn vcn = mVcns.get(subGrp);
                 final VcnConfig vcnConfig = mConfigs.get(subGrp);
-                if (vcn != null) {
-                    if (vcnConfig == null) {
-                        // TODO: b/284381334 Investigate for the root cause of this issue
-                        // and handle it properly
-                        logWtf("Vcn instance exists but VcnConfig does not for " + subGrp);
-                    }
-
+                if (vcn != null && vcnConfig != null) {
                     if (vcn.getStatus() == VCN_STATUS_CODE_ACTIVE) {
                         isVcnManagedNetwork = true;
                     }
@@ -1120,6 +1125,8 @@
                             }
                         }
                     }
+                } else if (vcn != null && vcnConfig == null) {
+                    logWtf("Vcn instance exists but VcnConfig does not for " + subGrp);
                 }
             }
 
diff --git a/services/core/java/com/android/server/vcn/TelephonySubscriptionTracker.java b/services/core/java/com/android/server/vcn/TelephonySubscriptionTracker.java
index baf84cf..3392d03 100644
--- a/services/core/java/com/android/server/vcn/TelephonySubscriptionTracker.java
+++ b/services/core/java/com/android/server/vcn/TelephonySubscriptionTracker.java
@@ -436,6 +436,17 @@
             return mPrivilegedPackages.keySet();
         }
 
+        /** Returns all subscription groups */
+        @NonNull
+        public Set<ParcelUuid> getAllSubscriptionGroups() {
+            final Set<ParcelUuid> subGroups = new ArraySet<>();
+            for (SubscriptionInfo subInfo : mSubIdToInfoMap.values()) {
+                subGroups.add(subInfo.getGroupUuid());
+            }
+
+            return subGroups;
+        }
+
         /** Checks if the provided package is carrier privileged for the specified sub group. */
         public boolean packageHasPermissionsForSubscriptionGroup(
                 @NonNull ParcelUuid subGrp, @NonNull String packageName) {
diff --git a/tests/vcn/java/com/android/server/VcnManagementServiceTest.java b/tests/vcn/java/com/android/server/VcnManagementServiceTest.java
index 7e0bbc4..3828a71 100644
--- a/tests/vcn/java/com/android/server/VcnManagementServiceTest.java
+++ b/tests/vcn/java/com/android/server/VcnManagementServiceTest.java
@@ -70,6 +70,7 @@
 import android.net.NetworkCapabilities;
 import android.net.NetworkRequest;
 import android.net.Uri;
+import android.net.vcn.Flags;
 import android.net.vcn.IVcnStatusCallback;
 import android.net.vcn.IVcnUnderlyingNetworkPolicyListener;
 import android.net.vcn.VcnConfig;
@@ -84,6 +85,7 @@
 import android.os.UserHandle;
 import android.os.UserManager;
 import android.os.test.TestLooper;
+import android.platform.test.flag.junit.SetFlagsRule;
 import android.telephony.SubscriptionInfo;
 import android.telephony.SubscriptionManager;
 import android.telephony.TelephonyManager;
@@ -102,6 +104,7 @@
 import com.android.server.vcn.util.PersistableBundleUtils.PersistableBundleWrapper;
 
 import org.junit.Before;
+import org.junit.Rule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
@@ -119,6 +122,8 @@
 @RunWith(AndroidJUnit4.class)
 @SmallTest
 public class VcnManagementServiceTest {
+    @Rule public final SetFlagsRule mSetFlagsRule = new SetFlagsRule();
+
     private static final String CONTEXT_ATTRIBUTION_TAG = "VCN";
     private static final String TEST_PACKAGE_NAME =
             VcnManagementServiceTest.class.getPackage().getName();
@@ -288,6 +293,8 @@
         doReturn(Collections.singleton(TRANSPORT_WIFI))
                 .when(mMockDeps)
                 .getRestrictedTransports(any(), any(), any());
+
+        mSetFlagsRule.enableFlags(Flags.FLAG_FIX_CONFIG_GARBAGE_COLLECTION);
     }
 
 
@@ -438,6 +445,14 @@
             return subIds;
         }).when(snapshot).getAllSubIdsInGroup(any());
 
+        doAnswer(invocation -> {
+            final Set<ParcelUuid> subGroups = new ArraySet<>();
+            for (Entry<Integer, ParcelUuid> entry : subIdToGroupMap.entrySet()) {
+                subGroups.add(entry.getValue());
+            }
+            return subGroups;
+        }).when(snapshot).getAllSubscriptionGroups();
+
         return snapshot;
     }
 
@@ -1483,6 +1498,28 @@
     }
 
     @Test
+    public void testGarbageCollectionKeepConfigUntilNewSnapshot() throws Exception {
+        setupActiveSubscription(TEST_UUID_2);
+        startAndGetVcnInstance(TEST_UUID_2);
+
+        // Report loss of subscription from mSubMgr
+        doReturn(Collections.emptyList()).when(mSubMgr).getSubscriptionsInGroup(any());
+        triggerSubscriptionTrackerCbAndGetSnapshot(
+                TEST_UUID_2,
+                Collections.singleton(TEST_UUID_2),
+                Collections.singletonMap(TEST_SUBSCRIPTION_ID, TEST_UUID_2));
+
+        assertTrue(mVcnMgmtSvc.getConfigs().containsKey(TEST_UUID_2));
+
+        // Report loss of subscription from snapshot
+        triggerSubscriptionTrackerCbAndGetSnapshot(null, Collections.emptySet());
+
+        mTestLooper.moveTimeForward(VcnManagementService.CARRIER_PRIVILEGES_LOST_TEARDOWN_DELAY_MS);
+        mTestLooper.dispatchAll();
+        assertFalse(mVcnMgmtSvc.getConfigs().containsKey(TEST_UUID_2));
+    }
+
+    @Test
     public void testVcnCarrierConfigChangeUpdatesPolicyListener() throws Exception {
         setupActiveSubscription(TEST_UUID_2);