diff --git a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
index 4d1e7ef..e6e99f4 100644
--- a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
+++ b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
@@ -359,6 +359,7 @@
         } catch (IllegalStateException e) {
             // Silent if the rule already exists. Note that the errno EEXIST was rethrown as
             // IllegalStateException. See BpfMap#insertEntry.
+            return false;
         }
         return true;
     }
diff --git a/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java b/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java
index d28a397..026b1c3 100644
--- a/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java
+++ b/Tethering/apishim/common/com/android/networkstack/tethering/apishim/common/BpfCoordinatorShim.java
@@ -140,6 +140,8 @@
 
     /**
      * Adds a tethering IPv4 offload rule to appropriate BPF map.
+     *
+     * @return true iff the map was modified, false if the key already exists or there was an error.
      */
     public abstract boolean tetherOffloadRuleAdd(boolean downstream, @NonNull Tether4Key key,
             @NonNull Tether4Value value);
diff --git a/framework/src/android/net/ConnectivityManager.java b/framework/src/android/net/ConnectivityManager.java
index 63a6cd2..1ebc4a3 100644
--- a/framework/src/android/net/ConnectivityManager.java
+++ b/framework/src/android/net/ConnectivityManager.java
@@ -6734,4 +6734,33 @@
             throw e.rethrowFromSystemServer();
         }
     }
+
+    /**
+     * Get the specified ConnectivityService feature status. This method is for test code to check
+     * whether the feature is enabled or not.
+     * Note that tests can not just read DeviceConfig since ConnectivityService reads flag at
+     * startup. For example, it's possible that the current flag value is "disable"(-1) but the
+     * feature is enabled since the flag value was "enable"(1) when ConnectivityService started up.
+     * If the ConnectivityManager needs to check the ConnectivityService feature status for non-test
+     * purpose, define feature in {@link ConnectivityManagerFeature} and use
+     * {@link #isFeatureEnabled} instead.
+     *
+     * @param featureFlag  target flag for feature
+     * @return {@code true} if the feature is enabled, {@code false} if the feature is disabled.
+     * @throws IllegalArgumentException if the flag is invalid
+     *
+     * @hide
+     */
+    @RequiresPermission(anyOf = {
+            android.Manifest.permission.NETWORK_SETTINGS,
+            android.Manifest.permission.NETWORK_STACK,
+            NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK
+    })
+    public boolean isConnectivityServiceFeatureEnabledForTesting(final String featureFlag) {
+        try {
+            return mService.isConnectivityServiceFeatureEnabledForTesting(featureFlag);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
 }
diff --git a/framework/src/android/net/IConnectivityManager.aidl b/framework/src/android/net/IConnectivityManager.aidl
index 988cc92..47b3316 100644
--- a/framework/src/android/net/IConnectivityManager.aidl
+++ b/framework/src/android/net/IConnectivityManager.aidl
@@ -262,4 +262,6 @@
     IBinder getRoutingCoordinatorService();
 
     long getEnabledConnectivityManagerFeatures();
+
+    boolean isConnectivityServiceFeatureEnabledForTesting(String featureFlag);
 }
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index 9af250b..990f43e 100755
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -14505,4 +14505,14 @@
         }
         return features;
     }
+
+    @Override
+    public boolean isConnectivityServiceFeatureEnabledForTesting(String featureFlag) {
+        switch (featureFlag) {
+            case INGRESS_TO_VPN_ADDRESS_FILTERING:
+                return mIngressToVpnAddressFiltering;
+            default:
+                throw new IllegalArgumentException("Unknown flag: " + featureFlag);
+        }
+    }
 }
diff --git a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
index e186c6b..2db1db5 100755
--- a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
+++ b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
@@ -213,6 +213,8 @@
 
     private static final String AUTOMATIC_ON_OFF_KEEPALIVE_VERSION =
                 "automatic_on_off_keepalive_version";
+    private static final String INGRESS_TO_VPN_ADDRESS_FILTERING =
+            "ingress_to_vpn_address_filtering";
     // Enabled since version 1 means it's always enabled because the version is always above 1
     private static final String AUTOMATIC_ON_OFF_KEEPALIVE_ENABLED = "1";
     private static final long TEST_TCP_POLLING_TIMER_EXPIRED_PERIOD_MS = 60_000L;
@@ -1949,6 +1951,9 @@
      */
     private void doTestDropPacketToVpnAddress(final boolean duplicatedAddress)
             throws Exception {
+        assumeTrue(mCM.isConnectivityServiceFeatureEnabledForTesting(
+                INGRESS_TO_VPN_ADDRESS_FILTERING));
+
         final NetworkRequest request = new NetworkRequest.Builder()
                 .removeCapability(NetworkCapabilities.NET_CAPABILITY_NOT_VPN)
                 .removeCapability(NetworkCapabilities.NET_CAPABILITY_TRUSTED)