diff --git a/framework-t/src/android/net/NetworkTemplate.java b/framework-t/src/android/net/NetworkTemplate.java
index b3c70cf..9d0476e 100644
--- a/framework-t/src/android/net/NetworkTemplate.java
+++ b/framework-t/src/android/net/NetworkTemplate.java
@@ -61,6 +61,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
 import java.util.Set;
@@ -194,8 +195,22 @@
     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.TIRAMISU,
             publicAlternatives = "Use {@code Builder} instead.")
     public static NetworkTemplate buildTemplateMobileAll(@NonNull String subscriberId) {
+        final Set<String> set;
+        // Prevent from crash for b/273963543, where the OEMs still call into this method
+        // with null subscriberId and get crashed.
+        final int firstSdk = Build.VERSION.DEVICE_INITIAL_SDK_INT;
+        if (firstSdk > Build.VERSION_CODES.TIRAMISU && subscriberId == null) {
+            throw new IllegalArgumentException("buildTemplateMobileAll does not accept null"
+                    + " subscriberId on Android U devices or above");
+        }
+        if (subscriberId == null) {
+            set = new HashSet<>();
+            set.add(null);
+        } else {
+            set = Set.of(subscriberId);
+        }
         return new NetworkTemplate.Builder(MATCH_MOBILE).setMeteredness(METERED_YES)
-                .setSubscriberIds(Set.of(subscriberId)).build();
+                .setSubscriberIds(set).build();
     }
 
     /**
@@ -410,12 +425,20 @@
             // subscriber ID.
             case MATCH_CARRIER:
                 if (matchSubscriberIds.length == 0) {
-                    throw new IllegalArgumentException("checkValidMatchSubscriberIds with empty"
-                            + " list of ids for rule" + getMatchRuleName(matchRule));
+                    throw new IllegalArgumentException("matchSubscriberIds may not contain"
+                            + " null for rule " + getMatchRuleName(matchRule));
                 }
-                // fall through
-            case MATCH_MOBILE:
                 if (CollectionUtils.contains(matchSubscriberIds, null)) {
+                    throw new IllegalArgumentException("matchSubscriberIds may not contain"
+                            + " null for rule " + getMatchRuleName(matchRule));
+                }
+                break;
+            case MATCH_MOBILE:
+                // Prevent from crash for b/273963543, where the OEMs still call into unsupported
+                // buildTemplateMobileAll with null subscriberId and get crashed.
+                final int firstSdk = Build.VERSION.DEVICE_INITIAL_SDK_INT;
+                if (firstSdk > Build.VERSION_CODES.TIRAMISU
+                        && CollectionUtils.contains(matchSubscriberIds, null)) {
                     throw new IllegalArgumentException("checkValidMatchSubscriberIds list of ids"
                             + " may not contain null for rule " + getMatchRuleName(matchRule));
                 }
diff --git a/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp b/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
index 3d22aac..dc5732f 100644
--- a/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
+++ b/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
@@ -136,10 +136,12 @@
 }
 
 void NetworkTraceHandler::OnStart(const StartArgs&) {
+  if (mIsTest) return;  // Don't touch non-hermetic bpf in test.
   mStarted = sPoller.Start(mPollMs);
 }
 
 void NetworkTraceHandler::OnStop(const StopArgs&) {
+  if (mIsTest) return;  // Don't touch non-hermetic bpf in test.
   if (mStarted) sPoller.Stop();
   mStarted = false;
 }
diff --git a/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp b/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
index 27dce75..f2c1a86 100644
--- a/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
+++ b/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
@@ -33,14 +33,6 @@
 using ::perfetto::protos::TracePacket;
 using ::perfetto::protos::TrafficDirection;
 
-// This handler makes OnStart and OnStop a no-op so that tracing is not really
-// started on the device.
-class HandlerForTest : public NetworkTraceHandler {
- public:
-  void OnStart(const StartArgs&) override {}
-  void OnStop(const StopArgs&) override {}
-};
-
 class NetworkTraceHandlerTest : public testing::Test {
  protected:
   // Starts a tracing session with the handler under test.
@@ -52,7 +44,7 @@
 
     perfetto::DataSourceDescriptor dsd;
     dsd.set_name("test.network_packets");
-    HandlerForTest::Register(dsd);
+    NetworkTraceHandler::Register(dsd, /*isTest=*/true);
 
     perfetto::TraceConfig cfg;
     cfg.add_buffers()->set_size_kb(1024);
@@ -94,7 +86,7 @@
                            std::vector<TracePacket>* output,
                            NetworkPacketTraceConfig config = {}) {
     auto session = StartTracing(config);
-    HandlerForTest::Trace([&](HandlerForTest::TraceContext ctx) {
+    NetworkTraceHandler::Trace([&](NetworkTraceHandler::TraceContext ctx) {
       ctx.GetDataSourceLocked()->Write(input, ctx);
       ctx.Flush();
     });
@@ -357,7 +349,7 @@
 
   auto session = StartTracing(config);
 
-  HandlerForTest::Trace([&](HandlerForTest::TraceContext ctx) {
+  NetworkTraceHandler::Trace([&](NetworkTraceHandler::TraceContext ctx) {
     ctx.GetDataSourceLocked()->Write(inputs[0], ctx);
     ctx.GetDataSourceLocked()->Write(inputs[1], ctx);
     ctx.GetDataSourceLocked()->Write(inputs[2], ctx);
diff --git a/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h b/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
index 9bc777b..bc10e68 100644
--- a/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
+++ b/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
@@ -70,6 +70,9 @@
   // Connects to the system Perfetto daemon and registers the trace handler.
   static void InitPerfettoTracing();
 
+  // When isTest is true, skip non-hermetic code.
+  NetworkTraceHandler(bool isTest = false) : mIsTest(isTest) {}
+
   // perfetto::DataSource overrides:
   void OnSetup(const SetupArgs& args) override;
   void OnStart(const StartArgs&) override;
@@ -92,6 +95,7 @@
 
   static internal::NetworkTracePoller sPoller;
   bool mStarted;
+  bool mIsTest;
 
   // Values from config, see proto for details.
   uint32_t mPollMs;
diff --git a/tests/common/java/android/net/netstats/NetworkTemplateTest.kt b/tests/common/java/android/net/netstats/NetworkTemplateTest.kt
index fb6759e..fd7bd74 100644
--- a/tests/common/java/android/net/netstats/NetworkTemplateTest.kt
+++ b/tests/common/java/android/net/netstats/NetworkTemplateTest.kt
@@ -30,16 +30,17 @@
 import android.net.NetworkTemplate.MATCH_WIFI
 import android.net.NetworkTemplate.NETWORK_TYPE_ALL
 import android.net.NetworkTemplate.OEM_MANAGED_ALL
+import android.os.Build
 import android.telephony.TelephonyManager
 import com.android.testutils.ConnectivityModuleTest
 import com.android.testutils.DevSdkIgnoreRule
 import com.android.testutils.SC_V2
+import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.junit.runners.JUnit4
-import kotlin.test.assertEquals
-import kotlin.test.assertFailsWith
 
 private const val TEST_IMSI1 = "imsi"
 private const val TEST_WIFI_KEY1 = "wifiKey1"
@@ -96,9 +97,27 @@
         }
 
         // Verify carrier and mobile template cannot contain one of subscriber Id is null.
-        listOf(MATCH_MOBILE, MATCH_CARRIER).forEach {
+        assertFailsWith<IllegalArgumentException> {
+            NetworkTemplate.Builder(MATCH_CARRIER).setSubscriberIds(setOf(null)).build()
+        }
+        val firstSdk = Build.VERSION.DEVICE_INITIAL_SDK_INT
+        if (firstSdk > Build.VERSION_CODES.TIRAMISU) {
             assertFailsWith<IllegalArgumentException> {
-                NetworkTemplate.Builder(it).setSubscriberIds(setOf(null)).build()
+                NetworkTemplate.Builder(MATCH_MOBILE).setSubscriberIds(setOf(null)).build()
+            }
+        } else {
+            NetworkTemplate.Builder(MATCH_MOBILE).setSubscriberIds(setOf(null)).build().let {
+                val expectedTemplate = NetworkTemplate(
+                    MATCH_MOBILE,
+                    arrayOfNulls<String>(1) /*subscriberIds*/,
+                    emptyArray<String>() /*wifiNetworkKey*/,
+                    METERED_ALL,
+                    ROAMING_ALL,
+                    DEFAULT_NETWORK_ALL,
+                    NETWORK_TYPE_ALL,
+                    OEM_MANAGED_ALL
+                )
+                assertEquals(expectedTemplate, it)
             }
         }
 
diff --git a/tests/unit/java/android/net/NetworkTemplateTest.kt b/tests/unit/java/android/net/NetworkTemplateTest.kt
index fc25fd8..2f6c76b 100644
--- a/tests/unit/java/android/net/NetworkTemplateTest.kt
+++ b/tests/unit/java/android/net/NetworkTemplateTest.kt
@@ -50,16 +50,17 @@
 import com.android.testutils.DevSdkIgnoreRule
 import com.android.testutils.DevSdkIgnoreRunner
 import com.android.testutils.assertParcelSane
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertNotEquals
+import kotlin.test.assertTrue
 import org.junit.Before
+import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.mockito.Mockito.mock
 import org.mockito.Mockito.`when`
 import org.mockito.MockitoAnnotations
-import kotlin.test.assertEquals
-import kotlin.test.assertFalse
-import kotlin.test.assertNotEquals
-import kotlin.test.assertTrue
 
 private const val TEST_IMSI1 = "imsi1"
 private const val TEST_IMSI2 = "imsi2"
@@ -70,6 +71,8 @@
 @RunWith(DevSdkIgnoreRunner::class)
 @DevSdkIgnoreRule.IgnoreUpTo(Build.VERSION_CODES.S_V2)
 class NetworkTemplateTest {
+    @get:Rule
+    val ignoreRule = DevSdkIgnoreRule()
     private val mockContext = mock(Context::class.java)
     private val mockWifiInfo = mock(WifiInfo::class.java)
 
@@ -215,6 +218,18 @@
         templateNullWifiKey.assertDoesNotMatch(identWifiNullKey)
     }
 
+    @DevSdkIgnoreRule.IgnoreAfter(Build.VERSION_CODES.TIRAMISU)
+    @Test
+    fun testBuildTemplateMobileAll_nullSubscriberId() {
+        val templateMobileAllWithNullImsi = buildTemplateMobileAll(null)
+        val setWithNull = HashSet<String?>().apply {
+            add(null)
+        }
+        val templateFromBuilder = NetworkTemplate.Builder(MATCH_MOBILE).setMeteredness(METERED_YES)
+            .setSubscriberIds(setWithNull).build()
+        assertEquals(templateFromBuilder, templateMobileAllWithNullImsi)
+    }
+
     @Test
     fun testMobileMatches() {
         val templateMobileImsi1 = buildTemplateMobileAll(TEST_IMSI1)