CI sees: openshift-cloud-network-config-controller_cloud-network-config-controller-7d9d894d87-ljwql_controller_previous.log.gz:E0818 07:49:23.163444 1 runtime.go:79] Observed a panic: "invalid memory address or nil pointer dereference"

example job: https://prow.ci.openshift.org/view/gs/origin-ci-test/logs/periodic-ci-openshift-multiarch-master-nightly-4.14-ocp-e2e-ovn-serial-aws-arm64/1692412344522510336

: Undiagnosed panic detected in pod expand_less0s{  pods/openshift-cloud-network-config-controller_cloud-network-config-controller-7d9d894d87-ljwql_controller_previous.log.gz:E0818 07:49:23.163444       1 runtime.go:79] Observed a panic: "invalid memory address or nil pointer dereference" (runtime error: invalid memory address or nil pointer dereference)}

I only saw 1 instance in 14 days according to search.ci:

$ podman run -it corbinu/alpine-w3m -dump -cols 200 "https://search.ci.openshift.org/?search=openshift-cloud-network-config-controller_cloud-network-config.*invalid+memory+address+or+nil+pointer+dereference&maxAge=336h&context=1&type=junit&name=.*4.14.*&excludeName=&maxMatches=5&maxBytes=20971520&groupBy=job" 
[openshift-cloud-netw] [14d] [Links     ] [junit          ]
[Search]
Job:
[.*4.14.*            ] [                    ] [5                   ] [20971520            ] [job  ]
[ ] Wrap lines
periodic-ci-openshift-multiarch-master-nightly-4.14-ocp-e2e-ovn-serial-aws-arm64 (all) - 31 runs, 29% failed, 11% of failures match = 3% impact
#1692412344522510336                                                                                                                                                         junit                                       7 days ago
# Undiagnosed panic detected in pod
pods/openshift-cloud-network-config-controller_cloud-network-config-controller-7d9d894d87-ljwql_controller_previous.log.gz:E0818 07:49:23.163444       1 runtime.go:79] Observed a panic: "invalid memory address or nil pointer dereference" (runtime error: invalid memory address or nil pointer dereference)


Found in 0.01% of runs (0.02% of failures) across 12046 total runs and 737 jobs (41.76% failed) in 1.045s - clear search | chart view - source code located on github

1.
2.
3.

stack trace in https://gcsweb-ci.apps.ci.l2s4.p1.openshiftapps.com/gcs/origin-ci-test/logs/periodic-ci-openshift-multiarch-master-nightly-4.14-ocp-e2e-ovn-serial-aws-arm64/1692412344522510336/artifacts/ocp-e2e-ovn-serial-aws-arm64/gather-extra/artifacts/pods/openshift-cloud-network-config-controller_cloud-network-config-controller-7d9d894d87-ljwql_controller_previous.log:

E0818 07:49:23.163444       1 runtime.go:79] Observed a panic: "invalid memory address or nil pointer dereference" (runtime error: invalid memory address or nil pointer dereference)
goroutine 147 [running]:
k8s.io/apimachinery/pkg/util/runtime.logPanic({0x257b020?, 0x44b20b0})
	/go/src/github.com/openshift/cloud-network-config-controller/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:75 +0x7c
k8s.io/apimachinery/pkg/util/runtime.HandleCrash({0x0, 0x0, 0x4000bec080?})
	/go/src/github.com/openshift/cloud-network-config-controller/vendor/k8s.io/apimachinery/pkg/util/runtime/runtime.go:49 +0x78
panic({0x257b020, 0x44b20b0})
	/usr/lib/golang/src/runtime/panic.go:884 +0x1f4
github.com/openshift/cloud-network-config-controller/pkg/cloudprovider.(*AWS).getSubnet(0x400048ad20, 0x4000b40420)
	/go/src/github.com/openshift/cloud-network-config-controller/pkg/cloudprovider/aws.go:266 +0x250
github.com/openshift/cloud-network-config-controller/pkg/cloudprovider.(*AWS).GetNodeEgressIPConfiguration(0x227b2c7d7d7d7d7d?, 0x2f2ec60?, {0x0, 0x0, 0x0})
	/go/src/github.com/openshift/cloud-network-config-controller/pkg/cloudprovider/aws.go:200 +0x158
github.com/openshift/cloud-network-config-controller/pkg/controller/node.(*NodeController).SyncHandler(0x4000b408f0, {0x400076eba0, 0x27})
	/go/src/github.com/openshift/cloud-network-config-controller/pkg/controller/node/node_controller.go:129 +0x384
github.com/openshift/cloud-network-config-controller/pkg/controller.(*CloudNetworkConfigController).processNextWorkItem.func1(0x4000b0bc20, {0x2367ec0?, 0x4000bec080?})
	/go/src/github.com/openshift/cloud-network-config-controller/pkg/controller/controller.go:152 +0xd0
github.com/openshift/cloud-network-config-controller/pkg/controller.(*CloudNetworkConfigController).processNextWorkItem(0x4000b0bc20)
	/go/src/github.com/openshift/cloud-network-config-controller/pkg/controller/controller.go:162 +0x44
github.com/openshift/cloud-network-config-controller/pkg/controller.(*CloudNetworkConfigController).runWorker(...)
	/go/src/github.com/openshift/cloud-network-config-controller/pkg/controller/controller.go:113
k8s.io/apimachinery/pkg/util/wait.BackoffUntil.func1(0x0?)
	/go/src/github.com/openshift/cloud-network-config-controller/vendor/k8s.io/apimachinery/pkg/util/wait/backoff.go:226 +0x40
k8s.io/apimachinery/pkg/util/wait.BackoffUntil(0x0?, {0x2f04380, 0x40005fa5d0}, 0x1, 0x4000190660)
	/go/src/github.com/openshift/cloud-network-config-controller/vendor/k8s.io/apimachinery/pkg/util/wait/backoff.go:227 +0x90
k8s.io/apimachinery/pkg/util/wait.JitterUntil(0x0?, 0x3b9aca00, 0x0, 0x0?, 0x0?)
	/go/src/github.com/openshift/cloud-network-config-controller/vendor/k8s.io/apimachinery/pkg/util/wait/backoff.go:204 +0x80
k8s.io/apimachinery/pkg/util/wait.Until(0x0?, 0x0?, 0x0?)
	/go/src/github.com/openshift/cloud-network-config-controller/vendor/k8s.io/apimachinery/pkg/util/wait/backoff.go:161 +0x28
created by github.com/openshift/cloud-network-config-controller/pkg/controller.(*CloudNetworkConfigController).Run
	/go/src/github.com/openshift/cloud-network-config-controller/pkg/controller/controller.go:99 +0x2e4
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
	panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x20d4d70]