Memory Limits Not Defined

• Query id: b14d1bc4-a208-45db-92f0-e21f8e2588e9
• Query name: Memory Limits Not Defined
• Platform: Kubernetes
• Severity: Medium
• Category: Resource Management
• URL: Github

Description

Memory limits should be defined for each container. This prevents potential resource exhaustion by ensuring that containers consume not more than the designated amount of memory
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - yaml file

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

Positive test num. 2 - yaml file

apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-deployment
  labels:
    app: test
spec:
  replicas: 3
  selector:
    matchLabels:
      app: test
  template:
    metadata:
      labels:
        app: test
    spec:
      containers:
        - name:  pause
          image: k8s.gcr.io/pause
          resources:
            limits:
              cpu: 1
            requests:
              cpu: 0.5
              memory: 512Mi

Code samples without security vulnerabilities

Negative test num. 1 - yaml file

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