[PATCH net-next v10 09/11] selftests/vsock: add namespace tests for CID collisions

Bobby Eshleman posted 11 patches 2 weeks ago
There is a newer version of this series
[PATCH net-next v10 09/11] selftests/vsock: add namespace tests for CID collisions
Posted by Bobby Eshleman 2 weeks ago
From: Bobby Eshleman <bobbyeshleman@meta.com>

Add tests to verify CID collision rules across different vsock namespace
modes.

1. Two VMs with the same CID cannot start in different global namespaces
   (ns_global_same_cid_fails)
2. Two VMs with the same CID can start in different local namespaces
   (ns_local_same_cid_ok)
3. VMs with the same CID can coexist when one is in a global namespace
   and another is in a local namespace (ns_global_local_same_cid_ok and
   ns_local_global_same_cid_ok)

The tests ns_global_local_same_cid_ok and ns_local_global_same_cid_ok
make sure that ordering does not matter.

The tests use a shared helper function namespaces_can_boot_same_cid()
that attempts to start two VMs with identical CIDs in the specified
namespaces and verifies whether VM initialization failed or succeeded.

Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
---
 tools/testing/selftests/vsock/vmtest.sh | 73 +++++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)

diff --git a/tools/testing/selftests/vsock/vmtest.sh b/tools/testing/selftests/vsock/vmtest.sh
index 86483249f490..a8bf78a5075d 100755
--- a/tools/testing/selftests/vsock/vmtest.sh
+++ b/tools/testing/selftests/vsock/vmtest.sh
@@ -48,6 +48,10 @@ readonly TEST_NAMES=(
 	ns_host_vsock_ns_mode_ok
 	ns_host_vsock_ns_mode_write_once_ok
 	ns_vm_local_mode_rejected
+	ns_global_same_cid_fails
+	ns_local_same_cid_ok
+	ns_global_local_same_cid_ok
+	ns_local_global_same_cid_ok
 )
 readonly TEST_DESCS=(
 	# vm_server_host_client
@@ -67,6 +71,17 @@ readonly TEST_DESCS=(
 
 	# ns_vm_local_mode_rejected
 	"Test that guest VM with G2H transport cannot set namespace mode to 'local'"
+	# ns_global_same_cid_fails
+	"Check QEMU fails to start two VMs with same CID in two different global namespaces."
+
+	# ns_local_same_cid_ok
+	"Check QEMU successfully starts two VMs with same CID in two different local namespaces."
+
+	# ns_global_local_same_cid_ok
+	"Check QEMU successfully starts one VM in a global ns and then another VM in a local ns with the same CID."
+
+	# ns_local_global_same_cid_ok
+	"Check QEMU successfully starts one VM in a local ns and then another VM in a global ns with the same CID."
 )
 
 readonly USE_SHARED_VM=(
@@ -553,6 +568,64 @@ test_ns_host_vsock_ns_mode_ok() {
 	return "${KSFT_PASS}"
 }
 
+namespaces_can_boot_same_cid() {
+	local ns0=$1
+	local ns1=$2
+	local pidfile1 pidfile2
+	local rc
+
+	pidfile1="$(create_pidfile)"
+	vm_start "${pidfile1}" "${ns0}"
+
+	pidfile2="$(create_pidfile)"
+	vm_start "${pidfile2}" "${ns1}"
+
+	rc=$?
+	terminate_pidfiles "${pidfile1}" "${pidfile2}"
+
+	return "${rc}"
+}
+
+test_ns_global_same_cid_fails() {
+	init_namespaces
+
+	if namespaces_can_boot_same_cid "global0" "global1"; then
+		return "${KSFT_FAIL}"
+	fi
+
+	return "${KSFT_PASS}"
+}
+
+test_ns_local_global_same_cid_ok() {
+	init_namespaces
+
+	if namespaces_can_boot_same_cid "local0" "global0"; then
+		return "${KSFT_PASS}"
+	fi
+
+	return "${KSFT_FAIL}"
+}
+
+test_ns_global_local_same_cid_ok() {
+	init_namespaces
+
+	if namespaces_can_boot_same_cid "global0" "local0"; then
+		return "${KSFT_PASS}"
+	fi
+
+	return "${KSFT_FAIL}"
+}
+
+test_ns_local_same_cid_ok() {
+	init_namespaces
+
+	if namespaces_can_boot_same_cid "local0" "local0"; then
+		return "${KSFT_FAIL}"
+	fi
+
+	return "${KSFT_PASS}"
+}
+
 test_ns_host_vsock_ns_mode_write_once_ok() {
 	for mode in "${NS_MODES[@]}"; do
 		local ns="${mode}0"

-- 
2.47.3
Re: [PATCH net-next v10 09/11] selftests/vsock: add namespace tests for CID collisions
Posted by Stefano Garzarella 1 week, 6 days ago
On Mon, Nov 17, 2025 at 06:00:32PM -0800, Bobby Eshleman wrote:
>From: Bobby Eshleman <bobbyeshleman@meta.com>
>
>Add tests to verify CID collision rules across different vsock namespace
>modes.
>
>1. Two VMs with the same CID cannot start in different global namespaces
>   (ns_global_same_cid_fails)
>2. Two VMs with the same CID can start in different local namespaces
>   (ns_local_same_cid_ok)
>3. VMs with the same CID can coexist when one is in a global namespace
>   and another is in a local namespace (ns_global_local_same_cid_ok and
>   ns_local_global_same_cid_ok)
>
>The tests ns_global_local_same_cid_ok and ns_local_global_same_cid_ok
>make sure that ordering does not matter.
>
>The tests use a shared helper function namespaces_can_boot_same_cid()
>that attempts to start two VMs with identical CIDs in the specified
>namespaces and verifies whether VM initialization failed or succeeded.
>
>Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
>---
> tools/testing/selftests/vsock/vmtest.sh | 73 +++++++++++++++++++++++++++++++++
> 1 file changed, 73 insertions(+)
>
>diff --git a/tools/testing/selftests/vsock/vmtest.sh b/tools/testing/selftests/vsock/vmtest.sh
>index 86483249f490..a8bf78a5075d 100755
>--- a/tools/testing/selftests/vsock/vmtest.sh
>+++ b/tools/testing/selftests/vsock/vmtest.sh
>@@ -48,6 +48,10 @@ readonly TEST_NAMES=(
> 	ns_host_vsock_ns_mode_ok
> 	ns_host_vsock_ns_mode_write_once_ok
> 	ns_vm_local_mode_rejected
>+	ns_global_same_cid_fails
>+	ns_local_same_cid_ok
>+	ns_global_local_same_cid_ok
>+	ns_local_global_same_cid_ok
> )
> readonly TEST_DESCS=(
> 	# vm_server_host_client
>@@ -67,6 +71,17 @@ readonly TEST_DESCS=(
>
> 	# ns_vm_local_mode_rejected
> 	"Test that guest VM with G2H transport cannot set namespace mode to 'local'"
>+	# ns_global_same_cid_fails
>+	"Check QEMU fails to start two VMs with same CID in two different global namespaces."
>+
>+	# ns_local_same_cid_ok
>+	"Check QEMU successfully starts two VMs with same CID in two different local namespaces."
>+
>+	# ns_global_local_same_cid_ok
>+	"Check QEMU successfully starts one VM in a global ns and then another VM in a local ns with the same CID."
>+
>+	# ns_local_global_same_cid_ok
>+	"Check QEMU successfully starts one VM in a local ns and then another VM in a global ns with the same CID."
> )
>
> readonly USE_SHARED_VM=(
>@@ -553,6 +568,64 @@ test_ns_host_vsock_ns_mode_ok() {
> 	return "${KSFT_PASS}"
> }
>
>+namespaces_can_boot_same_cid() {
>+	local ns0=$1
>+	local ns1=$2
>+	local pidfile1 pidfile2
>+	local rc
>+
>+	pidfile1="$(create_pidfile)"
>+	vm_start "${pidfile1}" "${ns0}"

Should we check also this return value or return an AND of both?

>+
>+	pidfile2="$(create_pidfile)"
>+	vm_start "${pidfile2}" "${ns1}"
>+
>+	rc=$?
>+	terminate_pidfiles "${pidfile1}" "${pidfile2}"
>+
>+	return "${rc}"
>+}
>+
>+test_ns_global_same_cid_fails() {
>+	init_namespaces
>+
>+	if namespaces_can_boot_same_cid "global0" "global1"; then
>+		return "${KSFT_FAIL}"
>+	fi
>+
>+	return "${KSFT_PASS}"
>+}
>+
>+test_ns_local_global_same_cid_ok() {
>+	init_namespaces
>+
>+	if namespaces_can_boot_same_cid "local0" "global0"; then
>+		return "${KSFT_PASS}"
>+	fi
>+
>+	return "${KSFT_FAIL}"
>+}
>+
>+test_ns_global_local_same_cid_ok() {
>+	init_namespaces
>+
>+	if namespaces_can_boot_same_cid "global0" "local0"; then
>+		return "${KSFT_PASS}"
>+	fi
>+
>+	return "${KSFT_FAIL}"
>+}
>+
>+test_ns_local_same_cid_ok() {

IIUC the naming convention, should this be with _fails() suffix?

Thanks,
Stefano

>+	init_namespaces
>+
>+	if namespaces_can_boot_same_cid "local0" "local0"; then
>+		return "${KSFT_FAIL}"
>+	fi
>+
>+	return "${KSFT_PASS}"
>+}
>+
> test_ns_host_vsock_ns_mode_write_once_ok() {
> 	for mode in "${NS_MODES[@]}"; do
> 		local ns="${mode}0"
>
>-- 
>2.47.3
>