fix: add defence logic for PV without claime ref

[zezaeoh]

What type of PR is this?

/kind bug

What this PR does / why we need it:
App crashes when deleting PVs without ClaimRef.

I1014 03:34:47.331898       1 controller.go:1471] delete "pvc-a6f2adab-036b-4833-b5c7-eaf84626c351": started
E1014 03:34:47.332068       1 runtime.go:79] Observed a panic: "invalid memory address or nil pointer dereference" (runtime error: invalid memory address or nil pointer dereference)
goroutine 257 [running]:
k8s.io/apimachinery/pkg/util/runtime.logPanic({0x1805020?, 0x29703c0})
	/workspace/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:75 +0x99
k8s.io/apimachinery/pkg/util/runtime.HandleCrash({0x0, 0x0, 0xc0005af920?})
	/workspace/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:49 +0x75
panic({0x1805020, 0x29703c0})
	/go/pkg/csiprow.XXXXDeFLHD/go-1.18/src/runtime/panic.go:838 +0x207
github.com/kubernetes-csi/external-provisioner/pkg/controller.(*csiProvisioner).getSecretsFromSC(0xc0003b8640, {0x1cdf738, 0xc0005b4300}, 0xc00071e500, 0x0, 0xc0006f08c0)
	/workspace/pkg/controller/controller.go:1272 +0x2a2
...

When we use Custom Resource RunnerSets of action-runner-controller,

That controller sets specific PV's ClaimRef to nil to release from PVC resource
https://github.com/actions-runner-controller/actions-runner-controller/blob/master/controllers/sync_volumes.go#L161-L176

In that case, this can lead to many PVs without a ClaimRef.

Which issue(s) this PR fixes:

Fixes #None

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Fix nil pointer crash for PV without ClaimRef

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: zezaeoh / name: Zezae Oh (06ccf62)

[k8s-ci-robot]

Welcome @zezaeoh!

It looks like this is your first PR to kubernetes-csi/external-provisioner 🎉. Please refer to our pull request process documentation to help your PR have a smooth ride to approval.

You will be prompted by a bot to use commands during the review process. Do not be afraid to follow the prompts! It is okay to experiment. Here is the bot commands documentation.

You can also check if kubernetes-csi/external-provisioner has its own contribution guidelines.

You may want to refer to our testing guide if you run into trouble with your tests not passing.

If you are having difficulty getting your pull request seen, please follow the recommended escalation practices. Also, for tips and tricks in the contribution process you may want to read the Kubernetes contributor cheat sheet. We want to make sure your contribution gets all the attention it needs!

Thank you, and welcome to Kubernetes. 😃

[k8s-ci-robot]

Hi @zezaeoh. Thanks for your PR.

I'm waiting for a kubernetes-csi member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[RaunakShah]

/ok-to-test

[RaunakShah]

Can you add some logs to the PR description to show that this error is triggered?

[zezaeoh]

@RaunakShah

Could you review again? :)

[RaunakShah]

/approve
/lgtm

[Madhu-1]

Commits need to be squashed into one.

[Madhu-1]

If we dont have the secrets, dont we need to allow deletion? lets the CSI driver try to handle it

[zezaeoh]

Actually, action-runner-controller deletes PV's ClaimRef intentionally to make PV orphan and reuse.
So, i think we should leave this PV as orphan

[Madhu-1]

Yes, that is for the ReclaimPolicy=Retained PV right, not for the ReclaimPolicy=Delete?

[zezaeoh]

Oh.. you are right! @Madhu-1
I'll follow your suggestion :) thx!!

[Madhu-1]

Change LGTM, you need review or approval from @msau42 @jsafrane

[zezaeoh]

@Madhu-1 @RaunakShah

Could you review again?

[RaunakShah]

@zezaeoh changes look good, can you add also add some testing results to the description? For example, the logs showing that csi-provisioner doesn't crash but also that the CSI driver eventually does not delete the volume?

[jsafrane]

@zezaeoh do you know how it's possible that a volume for PV without ClaimRef is deleted? That should be nearly impossible.

[jsafrane]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jsafrane, RaunakShah, zezaeoh

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [jsafrane]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment