Index: tests/sys/net/Makefile
===================================================================
--- tests/sys/net/Makefile
+++ tests/sys/net/Makefile
@@ -9,6 +9,7 @@
 ATF_TESTS_SH+=	if_bridge_test
 TEST_METADATA.if_bridge_test+=	required_programs="python"
 ATF_TESTS_SH+=	if_clone_test
+ATF_TESTS_SH+=	if_destroy_vnet
 ATF_TESTS_SH+=	if_gif
 ATF_TESTS_SH+=	if_lagg_test
 ATF_TESTS_SH+=	if_stf
Index: tests/sys/net/if_destroy_vnet.sh
===================================================================
--- /dev/null
+++ tests/sys/net/if_destroy_vnet.sh
@@ -0,0 +1,35 @@
+. $(atf_get_srcdir)/../common/vnet.subr
+
+atf_test_case "basic" "cleanup"
+basic_head()
+{
+	# https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=264981
+	atf_set descr 'Basic interface destruction after assigned to a VNET'
+	atf_set require.user root
+}
+
+basic_body()
+{
+	vnet_init
+
+	lo_if=$(vnet_mkloopback)
+	vnet_mkjail jifdestroy ${lo_if}
+	jexec jifdestroy ifconfig ${lo_if} up
+	jail -R jifdestroy
+	# Interface ${lo_if} must be back at the host level after destroying jail
+	# Pooling for jail shutdown is not sufficient, the vnet interface
+	# does not appear immediately on the host after jail shutdown.
+	# So using a racy sleep here.
+	sleep 1
+	atf_check -s exit:0 -o ignore ifconfig ${lo_if}
+}
+
+basic_cleanup()
+{
+	vnet_cleanup
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case "basic"
+}