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

[Bobby Eshleman <bobbyeshleman@gmail.com>]

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(+)

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