Memory Requests Not Defined

• Query id: 229588ef-8fde-40c8-8756-f4f2b5825ded
• Query name: Memory Requests Not Defined
• Platform: Kubernetes
• Severity: Medium
• Category: Resource Management
• URL: Github

Description

Memory requests should be defined for each container. This allows the kubelet to reserve the requested amount of system resources and prevents over-provisioning on individual nodes
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - yaml file

apiVersion: v1
kind: Pod
metadata:
  name: memory-demo
  namespace: mem-example
spec:
  containers:
  - name: memory-demo-ctr-1
    image: polinux/stress
    resources:
      limits:
        memory: "200Mi"
      requests:
        cpu: "0.5"
    command: ["stress"]
    args: ["--vm", "1", "--vm-bytes", "150M", "--vm-hang", "1"]
---
apiVersion: v1
kind: Pod
metadata:
  name: memory-demo-1
  namespace: mem-example
spec:
  containers:
  - name: memory-demo-ctr-2
    image: polinux/stress
    resources:
      limits:
        memory: "200Mi"
    command: ["stress"]
    args: ["--vm", "1", "--vm-bytes", "150M", "--vm-hang", "1"]
---
apiVersion: v1
kind: Pod
metadata:
  name: memory-demo-2
  namespace: mem-example
spec:
  containers:
  - name: memory-demo-ctr-3
    image: polinux/stress
    command: ["stress"]
    args: ["--vm", "1", "--vm-bytes", "150M", "--vm-hang", "1"]
---
apiVersion: v1
kind: Pod
metadata:
  name: memory-demo-3
  namespace: mem-example
spec:
  securityContext:
    runAsUser: 1000
    runAsGroup: 3000
    fsGroup: 2000
  volumes:
    - name: sec-ctx-vol
      emptyDir: { }
  containers:
  - name: memory-demo-ctr-4
    image: polinux/stress
    command: ["stress"]

Positive test num. 2 - yaml file

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-deployment2
  labels:
    app: test2
spec:
  replicas: 3
  selector:
    matchLabels:
      app: test2
  template:
    metadata:
      labels:
        app: test2
    spec:
      containers:
        - name:  pause
          image: k8s.gcr.io/pause
          resources:
            limits:
              cpu: 0.5
              memory: 512Mi

Code samples without security vulnerabilities

Negative test num. 1 - yaml file

apiVersion: v1
kind: Pod
metadata:
  name: memory-demo
  namespace: mem-example
spec:
  containers:
  - name: memory-demo-ctr
    image: polinux/stress
    resources:
      limits:
        memory: "200Mi"
      requests:
        memory: "100Mi"
    command: ["stress"]
    args: ["--vm", "1", "--vm-bytes", "150M", "--vm-hang", "1"]

Negative test num. 2 - yaml file

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-deployment-ctr-neg
  labels:
    app: test-neg
spec:
  replicas: 3
  selector:
    matchLabels:
      app: test-ctr-neg
  template:
    metadata:
      labels:
        app: test-ctr-neg
    spec:
      containers:
        - name:  pause
          image: k8s.gcr.io/pause
          resources:
            limits:
              cpu: 0.5
              memory: 512Mi
            requests:
              cpu: 0.5
              memory: 512Mi