[BUG] OT-CONTAINER-KIT/redis-operator: An incomplete cr.spec.kubernetesConfig.redisSecret causes nil-pointer reference inside operator

[Essoz]

What version of redis operator are you using?

redis-operator version: We are using redis-operator built from the HEAD and built from the latest release

• OT-CONTAINER-KIT/redis-operator@f1c547e

Does this issue reproduce with the latest release?
Yes, the problem reproduces with quay.io/opstree/redis-operator:v0.10.0

What operating system and processor architecture are you using (kubectl version)?

kubectl version Output

$ kubectl version
Client Version: version.Info{Major:"1", Minor:"23", GitVersion:"v1.23.1", GitCommit:"86ec240af8cbd1b60bcc4c03c20da9b98005b92e", GitTreeState:"clean", BuildDate:"2021-12-16T11:41:01Z", GoVersion:"go1.17.5", Compiler:"gc", Platform:"linux/amd64"}

What did you do?

To reproduce, apply the below cr file

cr_cluster.yaml

apiVersion: redis.redis.opstreelabs.in/v1beta1
kind: RedisCluster
metadata:
  name: test-cluster
spec:
  clusterSize: 3
  kubernetesConfig:
    image: quay.io/opstree/redis:v6.2.5
    imagePullPolicy: IfNotPresent
    redisSecret:
      name: igxkfdfzwl
    resources:
      limits:
        cpu: 101m
        memory: 128Mi
      requests:
        cpu: 101m
        memory: 128Mi
  redisExporter:
    enabled: true
    image: quay.io/opstree/redis-exporter:1.0
    imagePullPolicy: IfNotPresent
    resources:
      limits:
        cpu: 100m
        memory: 128Mi
      requests:
        cpu: 100m
        memory: 128Mi
  redisFollower:
    livenessProbe:
      tcpSocket: null
  storage:
    volumeClaimTemplate:
      spec:
        accessModes:
        - ReadWriteOnce
        resources:
          requests:
            storage: 1Gi

Observe that the operator crashes and restarts. Below is the operator crash log:

kubectl logs deployment.apps/redis-operator -n redis-operator output

1.6542940573701448e+09	INFO	controller_redis	Redis statefulset get action failed	{"Request.StatefulSet.Namespace": "default", "Request.StatefulSet.Name": "test-cluster-leader"}
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x141516d]
goroutine 344 [running]:

redis-operator/k8sutils.getEnvironmentVariables({0x17259a9, 0x7}, 0x0, 0xc0003be9d1, 0xc0006ab380, 0x0, 0xc0003be9d1, 0x0, 0x0)

/workspace/k8sutils/statefulset.go:419 +0x66d

redis-operator/k8sutils.generateContainerDef({0xc0000ff140, 0x0}, {{0xc00069e800, 0x1c}, {0xc0003be7d0, 0xc}, 0xc0006ab360, {0xc0006b03c0, 0x22}, {0xc0003be820, ...}, ...}, ...)

/workspace/k8sutils/statefulset.go:215 +0xcd

redis-operator/k8sutils.generateStatefulSetsDef({{0xc0000ff140, 0x13}, {0x0, 0x0}, {0xc0003be7c0, 0x7}, {0x0, 0x0}, {0x0, 0x0}, ...}, ...)

/workspace/k8sutils/statefulset.go:133 +0x145

redis-operator/k8sutils.CreateOrUpdateStateFul({_, _}, {{0xc0000ff140, 0x13}, {0x0, 0x0}, {0xc0003be7c0, 0x7}, {0x0, 0x0}, ...}, ...)

/workspace/k8sutils/statefulset.go:62 +0x1e7

redis-operator/k8sutils.RedisClusterSTS.CreateRedisClusterSetup({{0x1724f41, 0x6}, 0x0, 0x0, 0x0, 0x0}, 0xc0005af8c0)

/workspace/k8sutils/redis-cluster.go:155 +0x685

redis-operator/k8sutils.CreateRedisLeader(0xc0005af8c0)

/workspace/k8sutils/redis-cluster.go:108 +0xf1

redis-operator/controllers.(*RedisClusterReconciler).Reconcile(0xc00079f290, {0xc000623e90, 0x155c060}, {{{0xc0003be7c0, 0x1666c40}, {0xc0003be7b0, 0x30}}})

/workspace/controllers/rediscluster_controller.go:69 +0x316

sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Reconcile(0xc0000f40b0, {0x1940918, 0xc000623e90}, {{{0xc0003be7c0, 0x1666c40}, {0xc0003be7b0, 0x413a94}}})

/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:114 +0x26f

sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler(0xc0000f40b0, {0x1940870, 0xc0007b8a00}, {0x15b1740, 0xc0002ce240})

/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:311 +0x33e

sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem(0xc0000f40b0, {0x1940870, 0xc0007b8a00})

/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:266 +0x205

sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2()

/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:227 +0x85

created by sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2

/go/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:223 +0x357

What did you expect to see?
Redis-operator does not crash and (perhaps) rejecting the cr input.

What did you see instead?
Redis-operator crashed with the forementioned cr yaml file

Possible root cause
Neither key nor name are required under the field cr.spec.kubernetesConfig.redisSecret according to the CRD #L155-L163 inside the operator repo.

The operator crashes due to a nil-pointer reference when only one of the two fields: key and name is specified. The nil pointer reference is at https://github.com/OT-CONTAINER-KIT/redis-operator/blob/f1c547e26ece015c0c5cd8a8549ff277e8e7c2ab/k8sutils/statefulset.go#L412-L414

[tylergu]

The operator crashes due to a nil-pointer reference when only one of the two fields: key and name is specified. The nil pointer reference is at https://github.com/OT-CONTAINER-KIT/redis-operator/blob/f1c547e26ece015c0c5cd8a8549ff277e8e7c2ab/k8sutils/redis-cluster.go#L59-L62.

I think you need to refer to the actual dereference site, instead of this assignment site. The actual dereference site is here: https://github.com/OT-CONTAINER-KIT/redis-operator/blob/f1c547e26ece015c0c5cd8a8549ff277e8e7c2ab/k8sutils/statefulset.go#L412

This bug actually can be considered as two separate bugs, as there are two fields that can cause nil pointer dereference

[Essoz]

This makes sense.
I updated the link in the issue post.

[tylergu]

Issued: OT-CONTAINER-KIT/redis-operator#286

[Essoz]

Fixed: OT-CONTAINER-KIT/redis-operator#293