Values: Tighten controller.image.

Due to recent changes, the controller image can be run without privilege escalation:

- https://github.com/kubernetes/ingress-nginx/issues/8499
- https://github.com/kubernetes/ingress-nginx/pull/7449

charts/ingress-nginx/README.md

@@ -316,14 +316,17 @@ As of version `1.26.0` of this chart, by simply not providing any clusterIP valu
 | controller.hostPort.ports.http | int | `80` | 'hostPort' http port |
 | controller.hostPort.ports.https | int | `443` | 'hostPort' https port |
 | controller.hostname | object | `{}` | Optionally customize the pod hostname. |
-| controller.image.allowPrivilegeEscalation | bool | `true` |  |
+| controller.image.allowPrivilegeEscalation | bool | `false` |  |
 | controller.image.chroot | bool | `false` |  |
 | controller.image.digest | string | `"sha256:5b161f051d017e55d358435f295f5e9a297e66158f136321d9b04520ec6c48a3"` |  |
 | controller.image.digestChroot | string | `"sha256:5976b1067cfbca8a21d0ba53d71f83543a73316a61ea7f7e436d6cf84ddf9b26"` |  |
 | controller.image.image | string | `"ingress-nginx/controller"` |  |
 | controller.image.pullPolicy | string | `"IfNotPresent"` |  |
+| controller.image.readOnlyRootFilesystem | bool | `false` |  |
 | controller.image.registry | string | `"registry.k8s.io"` |  |
+| controller.image.runAsNonRoot | bool | `true` |  |
 | controller.image.runAsUser | int | `101` |  |
+| controller.image.seccompProfile.type | string | `"RuntimeDefault"` |  |
 | controller.image.tag | string | `"v1.9.4"` |  |
 | controller.ingressClass | string | `"nginx"` | For backwards compatibility with ingress.class annotation, use ingressClass. Algorithm is as follows, first ingressClassName is considered, if not present, controller looks for ingress.class annotation |
 | controller.ingressClassByName | bool | `false` | Process IngressClass per name (additionally as per spec.controller). |

charts/ingress-nginx/templates/_helpers.tpl

@@ -45,16 +45,24 @@ Controller container security context.
 {{- if .Values.controller.containerSecurityContext -}}
 {{- toYaml .Values.controller.containerSecurityContext -}}
 {{- else -}}
+runAsNonRoot: {{ .Values.controller.image.runAsNonRoot }}
+runAsUser: {{ .Values.controller.image.runAsUser }}
+allowPrivilegeEscalation: {{ or .Values.controller.image.allowPrivilegeEscalation .Values.controller.image.chroot }}
+{{- if .Values.controller.image.seccompProfile }}
+seccompProfile: {{ toYaml .Values.controller.image.seccompProfile | nindent 2 }}
+{{- end }}
 capabilities:
   drop:
   - ALL
   add:
   - NET_BIND_SERVICE
   {{- if .Values.controller.image.chroot }}
+  {{- if .Values.controller.image.seccompProfile }}
+  - SYS_ADMIN
+  {{- end }}
   - SYS_CHROOT
   {{- end }}
-runAsUser: {{ .Values.controller.image.runAsUser }}
-allowPrivilegeEscalation: {{ .Values.controller.image.allowPrivilegeEscalation }}
+readOnlyRootFilesystem: {{ .Values.controller.image.readOnlyRootFilesystem }}
 {{- end -}}
 {{- end -}}
 

charts/ingress-nginx/templates/controller-psp.yaml

@@ -4,6 +4,8 @@ apiVersion: policy/v1beta1
 kind: PodSecurityPolicy
 metadata:
   name: {{ include "ingress-nginx.fullname" . }}
+  annotations:
+    seccomp.security.alpha.kubernetes.io/allowedProfileNames: "*"
   labels:
     {{- include "ingress-nginx.labels" . | nindent 4 }}
     app.kubernetes.io/component: controller
@@ -14,9 +16,7 @@ spec:
   privileged: false
   hostPID: false
   hostIPC: false
-{{- if .Values.controller.hostNetwork }}
   hostNetwork: {{ .Values.controller.hostNetwork }}
-{{- end }}
 {{- if or .Values.controller.hostNetwork .Values.controller.hostPort.enabled }}
   hostPorts:
   {{- if .Values.controller.hostNetwork }}
@@ -67,15 +67,25 @@ spec:
   readOnlyRootFilesystem: false
   runAsUser:
     rule: MustRunAsNonRoot
+  runAsGroup:
+    rule: MustRunAs
+    ranges:
+      - min: 1
+        max: 65535
   supplementalGroups:
     rule: MustRunAs
     ranges:
       - min: 1
         max: 65535
-  allowPrivilegeEscalation: true
+  allowPrivilegeEscalation: {{ or .Values.controller.image.allowPrivilegeEscalation .Values.controller.image.chroot }}
+  requiredDropCapabilities:
+    - ALL
   allowedCapabilities:
     - NET_BIND_SERVICE
   {{- if .Values.controller.image.chroot }}
+  {{- if .Values.controller.image.seccompProfile }}
+    - SYS_ADMIN
+  {{- end }}
     - SYS_CHROOT
   {{- end }}
   seLinux:

charts/ingress-nginx/values.yaml

@@ -31,9 +31,13 @@ controller:
     digest: sha256:5b161f051d017e55d358435f295f5e9a297e66158f136321d9b04520ec6c48a3
     digestChroot: sha256:5976b1067cfbca8a21d0ba53d71f83543a73316a61ea7f7e436d6cf84ddf9b26
     pullPolicy: IfNotPresent
+    runAsNonRoot: true
     # www-data -> uid 101
     runAsUser: 101
-    allowPrivilegeEscalation: true
+    allowPrivilegeEscalation: false
+    seccompProfile:
+      type: RuntimeDefault
+    readOnlyRootFilesystem: false
   # -- Use an existing PSP instead of creating one
   existingPsp: ""
   # -- Configures the controller container name