[release-4.13] use net.JoinHostPort for URL construction

[stbenjam]

Summary

Cherry-pick of commit a8f745d from release-4.14 (part of PR #2996, originally from PR #2969).

• Replaces shell-based https://[${KUBERNETES_SERVICE_HOST}]:${KUBERNETES_SERVICE_PORT} with a Go-rendered {{.KubernetesServiceURL}} template value using net.JoinHostPort() in:
  • Multus admission controller YAML (bindata/network/multus-admission-controller/admission-controller.yaml)
  • Cloud network config controller YAML (bindata/cloud-network-config-controller/managed/controller.yaml)
• The corresponding Go code (pkg/network/cloud_network.go, pkg/network/multus_admission_controller.go) now constructs the URL properly using net.JoinHostPort(), which only adds brackets for IPv6 addresses
• The env var block that injected KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT into the init container is removed since the URL is now rendered directly into the template

Root cause

The previous code unconditionally wrapped KUBERNETES_SERVICE_HOST in square brackets when constructing the Kubernetes API server URL. Go 1.24.8+ (CVE-2025-47912) rejects brackets around non-IPv6 addresses, causing URL parsing failures.

Why this is needed

The 4.14 nightly gcp-ovn-rt-upgrade job upgrades from 4.13 to 4.14. The 4.13 source cluster hits this bug before the upgrade delivers the fixed 4.14 code.

Test plan

• Verify the Go code compiles: go build ./cmd/...
• Verify the YAML templates render correctly with hostname-based API server addresses
• Verify the YAML templates still work correctly with IPv6 API server addresses
• Verify 4.13 -> 4.14 upgrade succeeds

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[openshift-ci-robot]

@stbenjam: This pull request references Jira Issue OCPBUGS-84184, which is invalid:

• expected the bug to target either version "4.13." or "openshift-4.13.", but it targets "4.14.z" instead
• expected the bug to be in one of the following states: NEW, ASSIGNED, POST, but it is Verified instead
• expected dependent Jira Issue OCPBUGS-84183 to target a version in 4.14.0, 4.14.z, but it targets "4.15.z" instead

Comment /jira refresh to re-evaluate validity if changes to the Jira bug are made, or edit the title of this pull request to link to a different bug.

The bug has been updated to refer to the pull request using the external bug tracker.

Details

In response to this:

Summary

Cherry-pick of commit a8f745d from release-4.14 (part of PR #2996, originally from PR #2969).

• Replaces shell-based https://[${KUBERNETES_SERVICE_HOST}]:${KUBERNETES_SERVICE_PORT} with a Go-rendered {{.KubernetesServiceURL}} template value using net.JoinHostPort() in:
• Multus admission controller YAML (bindata/network/multus-admission-controller/admission-controller.yaml)
• Cloud network config controller YAML (bindata/cloud-network-config-controller/managed/controller.yaml)
• The corresponding Go code (pkg/network/cloud_network.go, pkg/network/multus_admission_controller.go) now constructs the URL properly using net.JoinHostPort(), which only adds brackets for IPv6 addresses
• The env var block that injected KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT into the init container is removed since the URL is now rendered directly into the template

Root cause

The previous code unconditionally wrapped KUBERNETES_SERVICE_HOST in square brackets when constructing the Kubernetes API server URL. Go 1.24.8+ (CVE-2025-47912) rejects brackets around non-IPv6 addresses, causing URL parsing failures.

Why this is needed

The 4.14 nightly gcp-ovn-rt-upgrade job upgrades from 4.13 to 4.14. The 4.13 source cluster hits this bug before the upgrade delivers the fixed 4.14 code.

Test plan

• Verify the Go code compiles: go build ./cmd/...
• Verify the YAML templates render correctly with hostname-based API server addresses
• Verify the YAML templates still work correctly with IPv6 API server addresses
• Verify 4.13 -> 4.14 upgrade succeeds

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 openshift-eng/jira-lifecycle-plugin repository.

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: stbenjam
Once this PR has been reviewed and has the lgtm label, please assign dougbtv for approval. For more information see the Code Review Process.

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Details

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[openshift-ci-robot]

@stbenjam: No Jira issue is referenced in the title of this pull request.
To reference a jira issue, add 'XYZ-NNN:' to the title of this pull request and request another refresh with /jira refresh.

Details

In response to this:

Summary

Cherry-pick of commit a8f745d from release-4.14 (part of PR #2996, originally from PR #2969).

• Replaces shell-based https://[${KUBERNETES_SERVICE_HOST}]:${KUBERNETES_SERVICE_PORT} with a Go-rendered {{.KubernetesServiceURL}} template value using net.JoinHostPort() in:
• Multus admission controller YAML (bindata/network/multus-admission-controller/admission-controller.yaml)
• Cloud network config controller YAML (bindata/cloud-network-config-controller/managed/controller.yaml)
• The corresponding Go code (pkg/network/cloud_network.go, pkg/network/multus_admission_controller.go) now constructs the URL properly using net.JoinHostPort(), which only adds brackets for IPv6 addresses
• The env var block that injected KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT into the init container is removed since the URL is now rendered directly into the template

Root cause

The previous code unconditionally wrapped KUBERNETES_SERVICE_HOST in square brackets when constructing the Kubernetes API server URL. Go 1.24.8+ (CVE-2025-47912) rejects brackets around non-IPv6 addresses, causing URL parsing failures.

Why this is needed

The 4.14 nightly gcp-ovn-rt-upgrade job upgrades from 4.13 to 4.14. The 4.13 source cluster hits this bug before the upgrade delivers the fixed 4.14 code.

Test plan

• Verify the Go code compiles: go build ./cmd/...
• Verify the YAML templates render correctly with hostname-based API server addresses
• Verify the YAML templates still work correctly with IPv6 API server addresses
• Verify 4.13 -> 4.14 upgrade succeeds

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 openshift-eng/jira-lifecycle-plugin repository.

[openshift-ci]

@stbenjam: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-aws-ovn-windows	98d8fbc	link	true	/test e2e-aws-ovn-windows
ci/prow/e2e-aws-sdn-network-reverse-migration	98d8fbc	link	true	/test e2e-aws-sdn-network-reverse-migration
ci/prow/e2e-aws-sdn-network-migration-rollback	98d8fbc	link	true	/test e2e-aws-sdn-network-migration-rollback
ci/prow/e2e-gcp-ovn	98d8fbc	link	true	/test e2e-gcp-ovn
ci/prow/e2e-aws-ovn-network-migration	98d8fbc	link	true	/test e2e-aws-ovn-network-migration
ci/prow/e2e-gcp-sdn	98d8fbc	link	true	/test e2e-gcp-sdn
ci/prow/e2e-aws-sdn-multi	98d8fbc	link	true	/test e2e-aws-sdn-multi
ci/prow/security	98d8fbc	link	false	/test security

Full PR test history. Your PR dashboard.

Details

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