When creating a pod with an additional network that contains a `spec.config.ipam.exclude` range, any address within the excluded range is still iterated while searching for a suitable IP candidate. As a result, pod creation times out when large exclude ranges are used.

with big exclude ranges, 100%

1. create network-attachment-definition with a large range:

$ cat <<EOF| oc apply -f -       
apiVersion: k8s.cni.cncf.io/v1                                            
kind: NetworkAttachmentDefinition
metadata:
  name: nad-w-excludes
spec:
  config: |-
    {
      "cniVersion": "0.3.1",
      "name": "macvlan-net",
      "type": "macvlan",
      "master": "ens3",
      "mode": "bridge",
      "ipam": {
         "type": "whereabouts",
         "range": "fd43:01f1:3daa:0baa::/64",
         "exclude": [ "fd43:01f1:3daa:0baa::/100" ],
         "log_file": "/tmp/whereabouts.log",
         "log_level" : "debug"
      }
    }
EOF
2. create a pod with the network attached:

$ cat <<EOF|oc apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: pod-with-exclude-range
  annotations:
    k8s.v1.cni.cncf.io/networks: nad-w-excludes
spec:
  containers:
  - name: pod-1
    image: openshift/hello-openshift
EOF

3. check pod status, event log and whereabouts logs after a while: 

$ oc get pods
NAME                        READY   STATUS              RESTARTS   AGE
pod-with-exclude-range      0/1     ContainerCreating   0          2m23s

$ oc get events
<...>
6m39s       Normal    Scheduled                                    pod/pod-with-exclude-range                   Successfully assigned default/pod-with-exclude-range to <worker-node>
6m37s       Normal    AddedInterface                               pod/pod-with-exclude-range                   Add eth0 [10.129.2.49/23] from openshift-sdn
2m39s       Warning   FailedCreatePodSandBox                       pod/pod-with-exclude-range                   Failed to create pod sandbox: rpc error: code = DeadlineExceeded desc = context deadline exceeded

$ oc debug node/<worker-node> - tail /host/tmp/whereabouts.log
Starting pod/<worker-node>-debug ...
To use host binaries, run `chroot /host`
2022-10-27T14:14:50Z [debug] Finished leader election
2022-10-27T14:14:50Z [debug] IPManagement: {fd43:1f1:3daa:baa::1 ffffffffffffffff0000000000000000} , <nil>
2022-10-27T14:14:59Z [debug] Used defaults from parsed flat file config @ /etc/kubernetes/cni/net.d/whereabouts.d/whereabouts.conf
2022-10-27T14:14:59Z [debug] ADD - IPAM configuration successfully read: {Name:macvlan-net Type:whereabouts Routes:[] Datastore:kubernetes Addresses:[] OmitRanges:[fd43:01f1:3daa:0baa::/80] DNS: {Nameservers:[] Domain: Search:[] Options:[]} Range:fd43:1f1:3daa:baa::/64 RangeStart:fd43:1f1:3daa:baa:: RangeEnd:<nil> GatewayStr: EtcdHost: EtcdUsername: EtcdPassword:********* EtcdKeyFile: EtcdCertFile: EtcdCACertFile: LeaderLeaseDuration:1500 LeaderRenewDeadline:1000 LeaderRetryPeriod:500 LogFile:/tmp/whereabouts.log LogLevel:debug OverlappingRanges:true SleepForRace:0 Gateway:<nil> Kubernetes: {KubeConfigPath:/etc/kubernetes/cni/net.d/whereabouts.d/whereabouts.kubeconfig K8sAPIRoot:} ConfigurationPath:PodName:pod-with-exclude-range PodNamespace:default} 
2022-10-27T14:14:59Z [debug] Beginning IPAM for ContainerID: f4ffd0e07d6c1a2b6ffb0fa29910c795258792bb1a1710ff66f6b48fab37af82
2022-10-27T14:14:59Z [debug] Started leader election
2022-10-27T14:14:59Z [debug] OnStartedLeading() called
2022-10-27T14:14:59Z [debug] Elected as leader, do processing
2022-10-27T14:14:59Z [debug] IPManagement - mode: 0 / containerID:f4ffd0e07d6c1a2b6ffb0fa29910c795258792bb1a1710ff66f6b48fab37af82 / podRef: default/pod-with-exclude-range
2022-10-27T14:14:59Z [debug] IterateForAssignment input >> ip: fd43:1f1:3daa:baa:: | ipnet: {fd43:1f1:3daa:baa:: ffffffffffffffff0000000000000000} | first IP: fd43:1f1:3daa:baa::1 | last IP: fd43:1f1:3daa:baa:ffff:ffff:ffff:ffff

Failed to create pod sandbox: rpc error: code = DeadlineExceeded desc = context deadline exceeded

additional network gets attached to the pod