linux node handler: add initial fuzz coverage

[AdamKorcz]

Signed-off-by: AdamKorcz adam@adalogics.com

Adds a fuzzer that creates a linux node handler, adds a node, refreshes, deletes, and refreshes again.
This fuzzer is meant to add initial fuzz test coverage of the linux node handler.

Add initial fuzz coverage of linux node handler.

[github-actions]

This pull request has been automatically marked as stale because it
has not had recent activity. It will be closed if no further activity
occurs. Thank you for your contributions.

[AdamKorcz]

Rebased

[dylandreimerink]

Hi @AdamKorcz, sorry you have had to wait so long for a reply on this PR, it slipped through the cracks. I stumbled upon this PR just now during some cleanup work.

I am vaguely aware of the fact that there are fuzzers running somewhere, but I believe those pre-date the official go fuzzing framework. How will we utilize these new fuzzing targets and will they get picked up by the existing systems?

[dylandreimerink]

The code itself looks sane to me

[dylandreimerink]

/test

Job 'Cilium-PR-K8s-1.24-kernel-5.4' failed:

Click to show.

Test Name

K8sDatapathConfig Encapsulation Check connectivity with transparent encryption, VXLAN, and endpoint routes

Failure Output

FAIL: Kubernetes DNS did not become ready in time

If it is a flake and a GitHub issue doesn't already exist to track it, comment /mlh new-flake Cilium-PR-K8s-1.24-kernel-5.4 so I can create one.

Job 'Cilium-PR-K8s-1.25-kernel-4.19' failed:

Click to show.

Test Name

K8sDatapathConfig Encapsulation Check connectivity with transparent encryption, VXLAN, and endpoint routes

Failure Output

FAIL: Kubernetes DNS did not become ready in time

If it is a flake and a GitHub issue doesn't already exist to track it, comment /mlh new-flake Cilium-PR-K8s-1.25-kernel-4.19 so I can create one.