Re: [PATCH net-next v14 12/12] selftests/vsock: add tests for namespace deletion

[Stefano Garzarella <sgarzare@redhat.com>]

On Mon, Jan 12, 2026 at 07:11:21PM -0800, Bobby Eshleman wrote:
>From: Bobby Eshleman <bobbyeshleman@meta.com>
>
>Add tests that validate vsock sockets are resilient to deleting
>namespaces. The vsock sockets should still function normally.
>
>The function check_ns_delete_doesnt_break_connection() is added to
>re-use the step-by-step logic of 1) setup connections, 2) delete ns,
>3) check that the connections are still ok.
>
>Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
>---
>Changes in v13:
>- remove tests that change the mode after socket creation (this is not
>  supported behavior now and the immutability property is tested in other
>  tests)
>- remove "change_mode" behavior of
>  check_ns_changes_dont_break_connection() and rename to
>  check_ns_delete_doesnt_break_connection() because we only need to test
>  namespace deletion (other tests confirm that the mode cannot change)
>
>Changes in v11:
>- remove pipefile (Stefano)
>
>Changes in v9:
>- more consistent shell style
>- clarify -u usage comment for pipefile
>---
> tools/testing/selftests/vsock/vmtest.sh | 84 +++++++++++++++++++++++++++++++++
> 1 file changed, 84 insertions(+)

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

>
>diff --git a/tools/testing/selftests/vsock/vmtest.sh b/tools/testing/selftests/vsock/vmtest.sh
>index a9eaf37bc31b..dc8dbe74a6d0 100755
>--- a/tools/testing/selftests/vsock/vmtest.sh
>+++ b/tools/testing/selftests/vsock/vmtest.sh
>@@ -68,6 +68,9 @@ readonly TEST_NAMES=(
> 	ns_same_local_loopback_ok
> 	ns_same_local_host_connect_to_local_vm_ok
> 	ns_same_local_vm_connect_to_local_host_ok
>+	ns_delete_vm_ok
>+	ns_delete_host_ok
>+	ns_delete_both_ok
> )
> readonly TEST_DESCS=(
> 	# vm_server_host_client
>@@ -135,6 +138,15 @@ readonly TEST_DESCS=(
>
> 	# ns_same_local_vm_connect_to_local_host_ok
> 	"Run vsock_test client in VM in a local ns with server in same ns."
>+
>+	# ns_delete_vm_ok
>+	"Check that deleting the VM's namespace does not break the socket connection"
>+
>+	# ns_delete_host_ok
>+	"Check that deleting the host's namespace does not break the socket connection"
>+
>+	# ns_delete_both_ok
>+	"Check that deleting the VM and host's namespaces does not break the socket connection"
> )
>
> readonly USE_SHARED_VM=(
>@@ -1287,6 +1299,78 @@ test_vm_loopback() {
> 	return "${KSFT_PASS}"
> }
>
>+check_ns_delete_doesnt_break_connection() {
>+	local pipefile pidfile outfile
>+	local ns0="global0"
>+	local ns1="global1"
>+	local port=12345
>+	local pids=()
>+	local rc=0
>+
>+	init_namespaces
>+
>+	pidfile="$(create_pidfile)"
>+	if ! vm_start "${pidfile}" "${ns0}"; then
>+		return "${KSFT_FAIL}"
>+	fi
>+	vm_wait_for_ssh "${ns0}"
>+
>+	outfile=$(mktemp)
>+	vm_ssh "${ns0}" -- \
>+		socat VSOCK-LISTEN:"${port}",fork STDOUT > "${outfile}" 2>/dev/null &
>+	pids+=($!)
>+	vm_wait_for_listener "${ns0}" "${port}" "vsock"
>+
>+	# We use a pipe here so that we can echo into the pipe instead of using
>+	# socat and a unix socket file. We just need a name for the pipe (not a
>+	# regular file) so use -u.
>+	pipefile=$(mktemp -u /tmp/vmtest_pipe_XXXX)
>+	ip netns exec "${ns1}" \
>+		socat PIPE:"${pipefile}" VSOCK-CONNECT:"${VSOCK_CID}":"${port}" &
>+	pids+=($!)
>+
>+	timeout "${WAIT_PERIOD}" \
>+		bash -c 'while [[ ! -e '"${pipefile}"' ]]; do sleep 1; done; exit 0'
>+
>+	if [[ "$1" == "vm" ]]; then
>+		ip netns del "${ns0}"
>+	elif [[ "$1" == "host" ]]; then
>+		ip netns del "${ns1}"
>+	elif [[ "$1" == "both" ]]; then
>+		ip netns del "${ns0}"
>+		ip netns del "${ns1}"
>+	fi
>+
>+	echo "TEST" > "${pipefile}"
>+
>+	timeout "${WAIT_PERIOD}" \
>+		bash -c 'while [[ ! -s '"${outfile}"' ]]; do sleep 1; done; exit 0'
>+
>+	if grep -q "TEST" "${outfile}"; then
>+		rc="${KSFT_PASS}"
>+	else
>+		rc="${KSFT_FAIL}"
>+	fi
>+
>+	terminate_pidfiles "${pidfile}"
>+	terminate_pids "${pids[@]}"
>+	rm -f "${outfile}" "${pipefile}"
>+
>+	return "${rc}"
>+}
>+
>+test_ns_delete_vm_ok() {
>+	check_ns_delete_doesnt_break_connection "vm"
>+}
>+
>+test_ns_delete_host_ok() {
>+	check_ns_delete_doesnt_break_connection "host"
>+}
>+
>+test_ns_delete_both_ok() {
>+	check_ns_delete_doesnt_break_connection "both"
>+}
>+
> shared_vm_test() {
> 	local tname
>
>
>-- 
>2.47.3
>