invalid memory address or nil pointer dereference in getReferencedRolloutAnalyses()

[jessesuen]

Summary

v1.0.1 can panic with:

time="2021-06-02T07:22:31Z" level=error msg="Recovered from panic: runtime error: invalid memory address or nil pointer dereference
goroutine 387 [running]:
runtime/debug.Stack(0xc008507200, 0x1c18d40, 0x2d971f0)
    /usr/local/go/src/runtime/debug/stack.go:24 +0x9f
github.com/argoproj/argo-rollouts/utils/controller.processNextWorkItem.func1.1.1(0xc007c6aee0, 0xc008507b30)
    /go/src/github.com/argoproj/argo-rollouts/utils/controller/controller.go:149 +0x5b
panic(0x1c18d40, 0x2d971f0)
    /usr/local/go/src/runtime/panic.go:965 +0x1b9
github.com/argoproj/argo-rollouts/rollout.(*rolloutContext).getReferencedRolloutAnalyses(0xc008cac380, 0xc008df07f8, 0x0, 0x0)
    /go/src/github.com/argoproj/argo-rollouts/rollout/controller.go:657 +0x36a
github.com/argoproj/argo-rollouts/rollout.(*rolloutContext).getRolloutReferencedResources(0xc008cac380, 0x2dea7c8, 0x0, 0x0)
    /go/src/github.com/argoproj/argo-rollouts/rollout/controller.go:511 +0x9d
github.com/argoproj/argo-rollouts/rollout.(*rolloutContext).getRolloutValidationErrors(0xc008cac380, 0x0, 0x0)
    /go/src/github.com/argoproj/argo-rollouts/rollout/controller.go:468 +0x6c
github.com/argoproj/argo-rollouts/rollout.(*rolloutContext).reconcile(0xc008cac380, 0xc0086c0000, 0xc008cac380)
    /go/src/github.com/argoproj/argo-rollouts/rollout/context.go:53 +0x2f
github.com/argoproj/argo-rollouts/rollout.(*Controller).syncHandler(0xc0007f2000, 0xc0068a32c0, 0x47, 0x0, 0x0)
    /go/src/github.com/argoproj/argo-rollouts/rollout/controller.go:387 +0x51a
github.com/argoproj/argo-rollouts/utils/controller.processNextWorkItem.func1.1(0x0, 0x0)
    /go/src/github.com/argoproj/argo-rollouts/utils/controller/controller.go:153 +0x7c
github.com/argoproj/argo-rollouts/utils/controller.processNextWorkItem.func1(0x21621d0, 0xc000617e60, 0x1e8bdd7, 0x7, 0xc000d1be60, 0xc00098ef40, 0x1b8c1a0, 0xc0068f82b0, 0x0, 0x0)
    /go/src/github.com/argoproj/argo-rollouts/utils/controller/controller.go:157 +0x323
github.com/argoproj/argo-rollouts/utils/controller.processNextWorkItem(0x21621d0, 0xc000617e60, 0x1e8bdd7, 0x7, 0xc000d1be60, 0xc00098ef40, 0x1)
    /go/src/github.com/argoproj/argo-rollouts/utils/controller/controller.go:169 +0x9a
github.com/argoproj/argo-rollouts/utils/controller.RunWorker(...)
    /go/src/github.com/argoproj/argo-rollouts/utils/controller/controller.go:104
github.com/argoproj/argo-rollouts/rollout.(*Controller).Run.func1()
    /go/src/github.com/argoproj/argo-rollouts/rollout/controller.go:319 +0xa5
k8s.io/apimachinery/pkg/util/wait.BackoffUntil.func1(0xc003060270)
    /go/pkg/mod/k8s.io/[email protected]/pkg/util/wait/wait.go:155 +0x5f
k8s.io/apimachinery/pkg/util/wait.BackoffUntil(0xc003060270, 0x2107e40, 0xc006846db0, 0x1, 0xc0000b8c60)
    /go/pkg/mod/k8s.io/[email protected]/pkg/util/wait/wait.go:156 +0x9b
k8s.io/apimachinery/pkg/util/wait.JitterUntil(0xc003060270, 0x3b9aca00, 0x0, 0x1, 0xc0000b8c60)
    /go/pkg/mod/k8s.io/[email protected]/pkg/util/wait/wait.go:133 +0x98
k8s.io/apimachinery/pkg/util/wait.Until(0xc003060270, 0x3b9aca00, 0xc0000b8c60)
    /go/pkg/mod/k8s.io/[email protected]/pkg/util/wait/wait.go:90 +0x4d
created by github.com/argoproj/argo-rollouts/rollout.(*Controller).Run
    /go/src/github.com/argoproj/argo-rollouts/rollout/controller.go:318 +0xac
" namespace=cloud-ops-vitefatjar2-usw2-e2e rollout=cloud-ops-rollout-vite-fat-jar2-e2e-usw2

Diagnostics

What version of Argo Rollouts are you running? v1.0.1

# Paste the logs from the rollout controller

# Logs for the entire controller:
kubectl logs -n argo-rollouts deployment/argo-rollouts

# Logs for a specific rollout:
kubectl logs -n argo-rollouts deployment/argo-rollouts | grep rollout=<ROLLOUTNAME>

---

Message from the maintainers:

Impacted by this bug? Give it a 👍. We prioritize the issues with the most 👍.

[jessesuen]

Offending code is recently modified analysis validation:

	} else if c.rollout.Spec.Strategy.Canary != nil {
		canary := c.rollout.Spec.Strategy.Canary
		for i, step := range canary.Steps {
			if step.Analysis != nil {
				templates, err := c.getReferencedAnalysisTemplates(c.rollout, step.Analysis, validation.InlineAnalysis, i)
				templates.Args = step.Analysis.Args   // <<<<< nil pointer dereference
				if err != nil {
					return nil, err
				}
				analysisTemplates = append(analysisTemplates, *templates)
			}
		}

@khhirani can you take a look?