Add emptyDir sizeLimit

 1apiVersion: kyverno.io/v1
 2kind: ClusterPolicy
 3metadata:
 4  name: add-emptydir-sizelimit
 5  annotations:
 6    policies.kyverno.io/title: Add emptyDir sizeLimit
 7    policies.kyverno.io/category: Other
 8    policies.kyverno.io/subject: Pod
 9    policies.kyverno.io/minversion: 1.6.0
10    kyverno.io/kyverno-version: 1.7.3,1.8.0-rc2
11    kyverno.io/kubernetes-version: "1.24"
12    policies.kyverno.io/description: >-
13      When a Pod requests an emptyDir, by default it does not have a size limit which
14      may allow it to consume excess or all of the space in the medium backing the volume.
15      This can quickly overrun a Node and may result in a denial of service for other
16      workloads. This policy adds a sizeLimit field to all Pods mounting emptyDir
17      volumes, if not present, and sets it to 100Mi.      
18spec: 
19  rules: 
20  - name: mutate-emptydir
21    match:
22      any:
23      - resources:
24          kinds:
25          - Pod
26    mutate:
27      foreach:
28      - list: "request.object.spec.volumes[]"
29        preconditions:
30          all:
31          - key: "{{element.keys(@)}}"
32            operator: AnyIn
33            value: emptyDir
34          - key: "{{element.emptyDir.sizeLimit || ''}}"
35            operator: Equals
36            value: ''
37        patchesJson6902: |-
38          - path: "/spec/volumes/{{elementIndex}}/emptyDir/sizeLimit"
39            op: add
40            value: 100Mi