[Nearby Connections] Fix UAF in OfflineServiceController during shutdown

PiperOrigin-RevId: 923343443

connections/implementation/offline_service_controller.cc

@@ -90,6 +90,7 @@ OfflineServiceController::StartListeningForIncomingConnections(
     ClientProxy* client, absl::string_view service_id,
     v3::ConnectionListener listener,
     const v3::ConnectionListeningOptions& options) {
+  if (stop_) return {{Status::kOutOfOrderApiCall}, {}};
   LOG(INFO) << "Client " << client->GetClientId()
             << " requested to start listening for service_id " << service_id;
   return pcp_manager_.StartListeningForIncomingConnections(
@@ -98,6 +99,7 @@ OfflineServiceController::StartListeningForIncomingConnections(
 
 void OfflineServiceController::StopListeningForIncomingConnections(
     ClientProxy* client) {
+  if (stop_) return;
   LOG(INFO) << "Client " << client->GetClientId()
             << " requested to stop listening for service_id "
             << client->GetListeningForIncomingConnectionsServiceId();

connections/implementation/offline_service_controller_test.cc

@@ -567,6 +567,33 @@ TEST_P(OfflineServiceControllerTest, ShutdownBwuManagerExecutors) {
   env_.Stop();
 }
 
+TEST_P(OfflineServiceControllerTest, TestNoStartListeningAfterStop) {
+  env_.Start();
+  OfflineSimulationUser user_a(kDeviceA, GetParam());
+  v3::ConnectionListener listener;
+  v3::ConnectionListeningOptions options;
+
+  user_a.Stop();
+
+  auto result = user_a.StartListeningForIncomingConnections(
+      std::string(kServiceId), listener, options);
+  EXPECT_EQ(result.first.value, Status::kOutOfOrderApiCall);
+
+  env_.Stop();
+}
+
+TEST_P(OfflineServiceControllerTest, TestNoStopListeningAfterStop) {
+  env_.Start();
+  OfflineSimulationUser user_a(kDeviceA, GetParam());
+
+  user_a.Stop();
+
+  // Verify that calling StopListening after Stop does not crash.
+  user_a.StopListeningForIncomingConnections();
+
+  env_.Stop();
+}
+
 INSTANTIATE_TEST_SUITE_P(ParametrisedOfflineServiceControllerTest,
                          OfflineServiceControllerTest,
                          ::testing::ValuesIn(kTestCases));

connections/implementation/pcp_manager.cc

@@ -122,6 +122,7 @@ PcpManager::StartListeningForIncomingConnections(
     ClientProxy* client, absl::string_view service_id,
     v3::ConnectionListener listener,
     const v3::ConnectionListeningOptions& options) {
+  if (shutdown_) return {{Status::kOutOfOrderApiCall}, {}};
   if (!SetCurrentPcpHandler(options.strategy)) {
     return {{Status::kError}, {}};
   }