Vulnerability Discussion

Enabling page poisoning in OpenShift improves memory safety, mitigates memory corruption vulnerabilities, aids in fault isolation, assists with debugging. It enhances the overall security and stability of the platform, reducing the risk of memory-related exploits and improving the resilience of applications running on OpenShift.

Check

Check the current CoreOS boot loader configuration has page poisoning enabled by executing the following:

for node in $(oc get node -oname); do oc debug $node -- chroot /host /bin/bash -c 'echo -n "$HOSTNAME "; grep page_poison /boot/loader/entries/*.conf|| echo "not found"' 2>/dev/null; done

If "page_poison" is not set to "1" or returns "not found", this is a finding.

Fix

Apply the machine config to enable page poisoning by executing the following:

for mcpool in $(oc get mcp -oname | sed "s:.*/::" ); do
echo "apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
metadata:
name: 05-kernelarg-page-poison-$mcpool
labels:
machineconfiguration.openshift.io/role: $mcpool
spec:
config:
ignition:
version: 3.1.0
kernelArguments:
- page_poison=1
" | oc apply -f -
done