Link configuration snippet to allow-snippet-annotations

[StefanLobbenmeierObjego]

What this PR does / why we need it:

Reduces confusion caused by breaking change in #10393

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• CVE Report (Scanner found CVE and adding report)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation only

Which issue/s this PR fixes

How Has This Been Tested?

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added unit and/or e2e tests to cover my changes.
• All new and existing tests passed.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: StefanLobbenmeierObjego / name: Stefan Lobbenmeier (03fbf16)

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[strongjz]

/lgtm

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: StefanLobbenmeierObjego, strongjz

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[StefanLobbenmeierObjego]

For some reason the link worked fine in the preview but seems to be broken now in the documentation. Not sure if something else broke it or I messed up the syntax?

[StefanLobbenmeierObjego]

I am guessing it was the extra /, removed it now. Sorry for the hassle.

[smanghi1]

hi @strongjz
i have a query regarding this change #10393, we recently did a big jump from v1.5.1 to v1.10.0.. don't see any issues till now. We added allow-snippet-annotations: true in our config map.. can we expect any vulnerability or security risk if we enable this flag?

[StefanLobbenmeierObjego]

can we expect any vulnerability or security risk if we enable this flag?

if you accept an inofficial answer - here is my take. allow-snippet-annotations is security relevant for multi tenant clusters

Basically if you know everyone that changes deployments to the cluster or have an approval process for it, you should be good. If you have random people changing the deployments, then they can change more via the snippet annotation that you might want. Not sure how much we are talking about, but I would expect that they can change the whole config file via this annotation.

in other words, it can give you more access to the cluster if you can already deploy and you can get more permissions. But for single tenant cluster if someone can deploy to your cluster that you do not trust you are pwned anyway.

That being said, take a look at the snippet annotations you currently have. It might be easy to migrate them away from snippets by replacing it with dedicated annotations. If you have snippets that you cannot migrate away from, I suggest you open an issue with those snippets to get further support.

(e.g. in our case we had this snippet which is trivial to replace but we did not replace it because it is not in this list: https://docs.nginx.com/nginx-ingress-controller/configuration/ingress-resources/advanced-configuration-with-annotations/)

     nginx.ingress.kubernetes.io/configuration-snippet: proxy_set_header X-Script-Name /pgadmin;

[strongjz]

The reason we implemented this kubernetes/kubernetes#126811