Files
home-network-k3s-impl/conformance/tests/l2-behavioral/vm-default-deny/chainsaw-test.yaml
T
jakman85andClaude Opus 4.8 3a59ef1918 fix(kubevirt): boot VMs via CDI DataVolume + EFI + real KVM (Phase 5)
VMs did not boot on the dev cluster. Three distinct live-verified causes,
all fixed GitOps-side:

1. containerDisk root failed at OCI init:
   exec "/container-disk-binary/usr/bin/container-disk": no such file.
   KubeVirt v1.9 supplies that binary to the volumerootdisk init container
   via a k8s-native `image` volume (VolumeSource.Image), gated by the ALPHA
   `ImageVolume` feature gate. k3s v1.31 has it DISABLED, so the apiserver
   silently prunes the image volume + its mount -> binary missing -> crash.
   (Proved: a server-side dry-run of a pod with an `image` volume drops it.)
   Fix: convert the VM roots in all three tests to CDI DataVolumes imported
   onto Longhorn PVCs (mounted disks bypass the container-disk/image-volume
   path). This is also the spec-required disk model (docs/06, R-STATE-01).
   vm-lifecycle now PASSES green live (VMI Running on start + restart).

2. Guest dropped to emergency mode: the containerdisks/fedora:41 image is
   UEFI-native (ESP + /boot mounted via systemd GPT auto-discovery); under
   KubeVirt's SeaBIOS default the ESP+/boot by-uuid mounts time out ->
   local-fs.target fails -> cloud-init runcmd/poweroff never runs.
   Fix: boot the VMs with EFI (OVMF, secureBoot:false) in all three tests
   and fixtures/vm.yaml. Confirmed live: emergency mode gone with EFI.

3. VMs ran under TCG software emulation (guests ~10x slow, saturating nodes
   until one went NotReady and VMs were evicted). Cause: useEmulation:true
   in the KubeVirt CR makes virt-controller NOT request devices.kubevirt.io/
   kvm, so /dev/kvm is never mounted and qemu falls back to TCG even though
   all nodes advertise kvm=1k / hypervisor=true. (Proved: `ls /dev/kvm` in a
   virt-launcher compute container = "No such file"; qemu accel = tcg.)
   Fix: useEmulation:false so the kvm device is requested and VMs run on real
   (nested) KVM. Requires Flux reconcile to take effect live (PM action).

The virt-handler clientcertificates tls.crt error is UNRELATED: node-labeller
(294 labels, hypervisor=true), device plugins, and VMI scheduling all work.

Also raised test exec timeouts to 30m (CDI import + boot) and, in
vm-default-deny, import the root BEFORE applying the default-deny NetworkPolicy
so the CDI importer's egress to quay.io is not severed by the policy.

Co-Authored-By: Claude Opus 4.8 <[email protected]>
2026-08-24 23:07:10 -05:00

239 lines
12 KiB
YAML

# =============================================================================
# L2 BEHAVIORAL — Default-deny applies to a VM (R-NET-01) [RUNNABLE / self-skips]
# Catalog: docs/14 (default-deny) — the IaaS partner of the container `default-deny`
# test. Spec: docs/03 "Default-deny baseline"; docs/06 ("default-deny +
# egress classes apply to VMs too"); ADR-0005/0015.
#
# GIVEN a VM in a namespace carrying the default-deny baseline (deny all east-west +
# egress, allow only DNS to the in-cluster resolver),
# WHEN the guest probes the network from INSIDE the VM,
# THEN DNS resolves (the one standing allow) but an undeclared public TCP dial is
# BLOCKED — the same default-deny fabric that governs pods governs the VM's
# own datapath (its traffic egresses via the virt-launcher pod netns, so a
# podSelector:{} NetworkPolicy covers it). R-NET-01 for IaaS.
#
# METHOD (virtctl-free): the VM's ROOT is a CDI DataVolume on Longhorn (a mounted
# PVC — NOT an ephemeral containerDisk, whose boot path is broken on this k3s cluster:
# KubeVirt v1.9 serves the container-disk binary via a k8s `image` volume gated by the
# ALPHA `ImageVolume` feature gate, disabled on k3s v1.31, so the apiserver prunes it
# and the guest dies at OCI init. DataVolume roots bypass that path and are the
# spec-required disk model — docs/06). cloud-init runs the two probes and writes a
# PASS/FAIL verdict to a raw Longhorn block disk, then powers off (RerunOnFailure =>
# stays down). A busybox reader pod reads the verdict back. The container default-deny
# test proves the datapath fail-closed (default-deny-failclosed, L3); this asserts
# the SAME baseline is enforced for a VM.
#
# RUNNABLE / SELF-SKIPPING: skips cleanly (green) until KubeVirt + longhorn exist.
#
# NOTE (bounded live-iteration, per the WS-VM report): the in-guest probe details
# (guest block-device ordering /dev/vdb, cluster-DNS injection into the guest, sh=bash
# for /dev/tcp on the Fedora containerDisk) are authored to the KubeVirt defaults and
# confirmed on the first live Phase-5 run; the test STRUCTURE and assertion are final.
# =============================================================================
apiVersion: chainsaw.kyverno.io/v1alpha1
kind: Test
metadata:
name: vm-default-deny
labels:
conformance.home.k3s/R-NET-01: "true"
annotations:
conformance.home.k3s/requirements: "R-NET-01"
conformance.home.k3s/layer: "L2"
conformance.home.k3s/safety-critical: "false"
conformance.home.k3s/executable: "true"
conformance.home.k3s/intent: >-
A VM under the default-deny baseline reaches only DNS from inside the guest;
an undeclared public TCP dial is blocked. Skips cleanly until KubeVirt + longhorn exist.
spec:
timeouts:
exec: 30m
steps:
- name: default-deny-applies-to-the-vm-datapath
try:
- script:
content: |
set -euo pipefail
NS="$NAMESPACE"
# -- Gate: skip cleanly (green) until KubeVirt + longhorn exist. --
if ! kubectl get crd virtualmachineinstances.kubevirt.io >/dev/null 2>&1; then
echo "SKIP: KubeVirt CRDs absent"; echo VM_DEFAULT_DENY_SKIPPED_OK; exit 0
fi
if ! kubectl get storageclass longhorn >/dev/null 2>&1; then
echo "SKIP: 'longhorn' StorageClass absent"; echo VM_DEFAULT_DENY_SKIPPED_OK; exit 0
fi
CANARY="vm-deny-$(date +%s%N)"
# -- GIVEN (disk): CDI imports the Fedora root onto a Longhorn PVC. This MUST happen
# BEFORE the default-deny NetworkPolicy below: default-deny (podSelector {}) also
# matches the CDI importer pod and would sever its egress to quay.io. The import is
# a one-time provisioning step; once the PVC holds the disk the VM boots with NO
# external egress, so applying default-deny AFTER the import still proves the VM's
# own datapath is fail-closed (the runbook's app-namespace equivalent is a scoped
# CiliumNetworkPolicy for the importer — see fixtures/vm.yaml). --
kubectl -n "$NS" apply -f - <<'EOF'
apiVersion: cdi.kubevirt.io/v1beta1
kind: DataVolume
metadata:
name: prober-rootdisk
spec:
source:
registry:
url: "docker://quay.io/containerdisks/fedora:41"
storage:
accessModes:
- ReadWriteOnce
storageClassName: longhorn
resources:
requests:
storage: 6Gi
EOF
dv_phase=""
for i in $(seq 1 120); do
dv_phase="$(kubectl -n "$NS" get dv prober-rootdisk -o jsonpath='{.status.phase}' 2>/dev/null || true)"
[ "$dv_phase" = "Succeeded" ] && break
sleep 10
done
[ "$dv_phase" = "Succeeded" ] || { echo "FAIL: CDI import did not Succeed (last='$dv_phase')" >&2; exit 1; }
echo "CDI import complete: prober-rootdisk Succeeded (Longhorn PVC)"
# -- GIVEN: the default-deny baseline in this namespace (deny all, allow only DNS to
# kube-system) — the exact shape Kyverno generates for app namespaces (docs/03).
# Applied AFTER the import so it governs the running VM's datapath (the point of the test). --
kubectl -n "$NS" apply -f - <<'EOF'
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: default-deny
spec:
podSelector: {}
policyTypes: [Ingress, Egress]
ingress: []
egress:
- to:
- namespaceSelector:
matchLabels:
kubernetes.io/metadata.name: kube-system
ports:
- { protocol: UDP, port: 53 }
- { protocol: TCP, port: 53 }
EOF
# -- The verdict block disk (Longhorn). --
kubectl -n "$NS" apply -f - <<'EOF'
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: vm-verdict
spec:
accessModes: [ReadWriteOnce]
volumeMode: Block
storageClassName: longhorn
resources:
requests:
storage: 1Gi
EOF
# -- The VM + the in-guest probe (quoted heredoc: many '$' in the probe; __CANARY__ sed'd). --
cat > /tmp/vm-deny.yaml <<'EOF'
apiVersion: kubevirt.io/v1
kind: VirtualMachine
metadata:
name: prober
spec:
runStrategy: RerunOnFailure
template:
metadata:
labels:
kubevirt.io/vm: prober
homelab.keithjackson.dev/egress-class: internet
spec:
domain:
# The containerdisks/fedora:41 image is UEFI-native (ESP + /boot mounted via
# systemd GPT auto-discovery). KubeVirt defaults to SeaBIOS, under which the guest
# boots to emergency mode (ESP + /boot by-uuid mounts time out -> local-fs.target
# fails) and cloud-init's runcmd/poweroff never runs. Boot with EFI (OVMF) so the
# guest reaches multi-user and the probe executes. secureBoot:false => no SMM needed.
firmware:
bootloader:
efi:
secureBoot: false
cpu: { cores: 1 }
memory: { guest: 1024Mi }
devices:
disks:
- name: rootdisk
disk: { bus: virtio }
- name: verdict
disk: { bus: virtio }
- name: cloudinit
disk: { bus: virtio }
resources:
requests:
memory: 1024Mi
volumes:
- name: rootdisk
dataVolume:
name: prober-rootdisk
- name: verdict
persistentVolumeClaim:
claimName: vm-verdict
- name: cloudinit
cloudInitNoCloud:
userData: |-
#cloud-config
runcmd:
- [ sh, -c, "getent hosts quay.io >/dev/null 2>&1 && DNS=1 || DNS=0; timeout 5 sh -c 'echo > /dev/tcp/1.1.1.1/443' >/dev/null 2>&1 && DENY=0 || DENY=1; V=FAIL; [ \"$DNS\" = 1 ] && [ \"$DENY\" = 1 ] && V=PASS; printf '%s' \"$V:__CANARY__\" | dd of=/dev/vdb bs=1 seek=0 conv=notrunc; sync; sleep 3; poweroff" ]
EOF
sed -i "s/__CANARY__/$CANARY/" /tmp/vm-deny.yaml
kubectl -n "$NS" apply -f /tmp/vm-deny.yaml
# -- WHEN: wait until the guest has run the probes and powered off. --
ok=""
for i in $(seq 1 90); do
phase="$(kubectl -n "$NS" get vmi prober -o jsonpath='{.status.phase}' 2>/dev/null || true)"
if [ "$phase" = "Succeeded" ] || { [ -z "$phase" ] && [ "$i" -gt 3 ]; }; then ok=1; break; fi
sleep 10
done
[ -n "$ok" ] || { echo "FAIL: guest never completed the probes+poweroff (last='$phase')" >&2; exit 1; }
# -- THEN: read the verdict from the Longhorn disk via a throwaway reader. --
kubectl -n "$NS" delete vm prober --wait=true --timeout=180s
kubectl -n "$NS" apply -f - <<'EOF'
apiVersion: v1
kind: Pod
metadata:
name: verdict-reader
spec:
restartPolicy: Never
containers:
- name: app
image: busybox:1.36.1
command: ["sh","-c","sleep 3600"]
volumeDevices:
- name: v
devicePath: /dev/verdict
volumes:
- name: v
persistentVolumeClaim:
claimName: vm-verdict
EOF
kubectl -n "$NS" wait --for=condition=Ready pod/verdict-reader --timeout=240s
GOT="$(kubectl -n "$NS" exec verdict-reader -- sh -c "dd if=/dev/verdict bs=1 count=$((5 + ${#CANARY})) 2>/dev/null")"
echo "verdict='$GOT' (expected PASS:$CANARY)"
case "$GOT" in
PASS:"$CANARY") echo VM_DEFAULT_DENY_OK ;;
*) echo "FAIL: default-deny not enforced for the VM (verdict='$GOT')" >&2; exit 1 ;;
esac
check:
(contains($stdout, 'VM_DEFAULT_DENY_OK') || contains($stdout, 'VM_DEFAULT_DENY_SKIPPED_OK')): true
finally:
- script:
content: |
kubectl -n "$NAMESPACE" delete vm prober --ignore-not-found --wait=false || true
kubectl -n "$NAMESPACE" delete pod verdict-reader --ignore-not-found --wait=false || true
kubectl -n "$NAMESPACE" delete dv prober-rootdisk --ignore-not-found --wait=false || true
kubectl -n "$NAMESPACE" delete pvc vm-verdict --ignore-not-found --wait=false || true
echo "cleanup best-effort; chainsaw namespace teardown finalizes"