fix(icms): pin LLS migration image digest missed by the chart import

[balajinvda]

Why

The icms-api chart was imported from the upstream sis-colocated-deploy chart
repo in #834 (merged 2026-08-17). The import was taken at roughly the upstream
2.0.0/2.0.1 state, so the security fix released as upstream tag 2.0.2
("fix(security): pin LLS migration image digest and record triage", 2026-08-14)
never landed here. 2.0.2 is still the newest upstream tag, so this is the only
gap of its kind.

The consequence is live: both LLS workloads rendered by this chart (the HMAC
rotation CronJob and the LLS migrations hook Job) resolve their image
through a mutable tag with pullPolicy: IfNotPresent. A registry compromise, a
tag move, or an unsafe operator override could run unreviewed code with OpenBao
access. Upstream closed that by pinning an immutable manifest digest; this repo
never got it.

Note that the sis.image helper for the main API container already supports a
digest here. Only sis.image.full, the helper used for the LLS workloads, was
left on the tag-only path.

What changed

Four files, all under deploy/helm/icms/:

• icms-api/templates/_helpers.tpl - sis.image.full now prefers a configured
  digest and renders registry/repository@digest, falling back to the existing
  required-tag path when no digest is set. Without this the pin below is inert.
• icms-api/values.yaml - documents the optional digest field on the
  hmacRotation image and defaults it to "", so consumers publishing into their
  own registry keep today's tag-based behavior unchanged.
• icms-api/values.versions.yaml - pins the multi-architecture OCI index digest
  for migration image tag 0.16.3. The tag is deliberately kept alongside the
  digest so Renovate and release automation retain a human-readable version.
• README.md - documents the digest-over-tag precedence.

No chart version bump: Chart.yaml carries version: 0.0.0 # set by CI.

Deliberately not ported

Upstream 2.0.2 touched seven files. Three have no equivalent here and are out
of scope for this PR rather than being given an invented home:

• .security-triage.yaml - upstream's copy is scoped to the chart repo
  (project: "sis-colocated-deploy", visibility: Internal). This repo's root
  .security-triage.yaml is a different document: project: "nvcf",
  visibility: Public, covering the whole monorepo. The upstream entries added
  in 2.0.2 are triage notes citing internal merge requests and internal
  scanner finding IDs, which do not belong in a public repo's security file.
• SECURITY.md - upstream's is a chart threat model. This repo's root
  SECURITY.md is a vulnerability reporting policy. Different documents; there
  is no threat-model doc here to update.
• renovate.json - upstream extended its regex manager to capture
  currentDigest so Renovate bumps tag and digest together. Verified this repo
  has no Renovate config at all (no renovate.json, .renovaterc*, or
  .github/renovate.json), so there is nothing to extend. Consequence worth
  flagging: until Renovate is wired up here, the pinned digest will not
  auto-refresh when the tag moves, and will need a manual update.

Verification

helm lint (helm v3.20.1):

$ helm lint icms-api
engine.go:214: [INFO] Missing required value: A valid image registry (.Values.sis.image.registry) is required!
engine.go:214: [INFO] Missing required value: A valid image repository (.Values.sis.image.repository) is required!
==> Linting icms-api
[INFO] Chart.yaml: icon is recommended

1 chart(s) linted, 0 chart(s) failed

The chart requires sis.image.registry/repository and sis.lls.enabled=true
before the LLS workloads render, so rendering used this override:

sis:
  image:
    registry: nvcr.io
    repository: example/icms-api
  lls:
    enabled: true
    hmacRotation:
      image:
        registry: nvcr.io
        repository: 0651155215864979/ncp-dev/nvcf-openbao-migrations

Digest lands in both LLS workloads:

$ helm template icms-api icms-api -f icms-api/values.yaml \
    -f icms-api/values.versions.yaml -f override.yaml \
    | grep -E '^kind:|nvcf-openbao-migrations'
...
kind: CronJob
              image: "nvcr.io/0651155215864979/ncp-dev/nvcf-openbao-migrations@sha256:6bb41be51d62c74b42f4d12af6581d343f6bc7205d02787a1958d994b91a998c"
kind: Job
          image: "nvcr.io/0651155215864979/ncp-dev/nvcf-openbao-migrations@sha256:6bb41be51d62c74b42f4d12af6581d343f6bc7205d02787a1958d994b91a998c"

Tag fallback is unchanged when no digest is set (no break for consumers using
their own registry):

$ helm template ... --set sis.lls.hmacRotation.image.tag=0.16.3   # no versions file
              image: "nvcr.io/0651155215864979/ncp-dev/nvcf-openbao-migrations:0.16.3"
          image: "nvcr.io/0651155215864979/ncp-dev/nvcf-openbao-migrations:0.16.3"

Digest wins when both are set:

$ helm template ... -f icms-api/values.versions.yaml --set sis.lls.hmacRotation.image.tag=9.9.9
              image: "nvcr.io/0651155215864979/ncp-dev/nvcf-openbao-migrations@sha256:6bb41be51d62c74b42f4d12af6581d343f6bc7205d02787a1958d994b91a998c"

Neither set still fails loudly rather than rendering a bare image name:

Error: execution error at (helm-nvcf-sis/templates/hook-lls-migrations.yaml:45:21):
A valid image tag is required for sis.lls.hmacRotation.image.tag

Digest string is now present in the repo, where it previously appeared nowhere:

$ grep -rn 6bb41be51d62c74b42f4d12af6581d343f6bc7205d02787a1958d994b91a998c .
deploy/helm/icms/icms-api/values.versions.yaml:33:        digest: "sha256:6bb41be51d62c74b42f4d12af6581d343f6bc7205d02787a1958d994b91a998c"

Testing

Helm lint and template only. Chart-values change with no unit-testable code
path; the render assertions above cover digest precedence, tag fallback, and the
missing-both error case.

References

Follows up #834.

Summary by CodeRabbit

• New Features

  • Added support for configuring immutable image digests for LLS migration and HMAC rotation images.
  • Configured digests take precedence over image tags when both are provided.
  • Added support for pinned multi-architecture OCI image references.

• Documentation

  • Updated Helm configuration guidance for image tags, digests, and immutable version pinning.

[coderabbitai]

📝 Walkthrough

Walkthrough

The Helm chart now supports immutable digests for LLS migration images. Configured digests take precedence over tags. The version overrides pin the HMAC rotation image to a multi-architecture OCI index digest.

Changes

LLS image digest configuration

Layer / File(s)	Summary
Digest configuration and rendering deploy/helm/icms/icms-api/values.yaml, deploy/helm/icms/icms-api/templates/_helpers.tpl	The LLS migration image accepts an optional digest. sis.image.full renders registry/repository@digest when configured and otherwise uses the tag.
Pinned image defaults and documentation deploy/helm/icms/icms-api/values.versions.yaml, deploy/helm/icms/README.md	The version overrides add the multi-architecture OCI index digest for hmacRotation:0.16.3. Documentation describes digest precedence and image pinning.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: 🔵 Low · up to 328e1

The change correctly adds immutable image pinning for the LLS workloads, but merge should proceed with explicit owner awareness to confirm that the committed registry endpoint is appropriate for repository configuration and that the digest matches the intended multi-architecture image.

Sequence Diagram(s)

sequenceDiagram
  participant HelmValues
  participant sisImageFull
  participant LLSWorkloads
  HelmValues->>sisImageFull: provide optional image digest
  sisImageFull->>LLSWorkloads: render digest-based image reference

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Suggested reviewers: athappa-nv

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title uses valid Conventional Commits syntax with the required scope. The fix type accurately describes pinning the LLS migration image to an immutable digest to address a security fix.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

Full details: Docstring Coverage

Explanation

No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0 files. (4 skipped: 4 unsupported.)

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/icms-port-sis-2-0-2-digest-pin

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[coderabbitai]

Actionable comments posted: 1

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Inline comments:
In `@deploy/helm/icms/icms-api/values.versions.yaml`:
- Line 31: Remove the Renovate metadata comment referencing the internal nvcr.io
NCP dev registry from values.versions.yaml, and rely on the approved private
Renovate configuration for this dependency instead.

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Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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📥 Commits

Reviewing files that changed from the base of the PR and between f8b622d and 328e1b6.

📒 Files selected for processing (4)

• deploy/helm/icms/README.md
• deploy/helm/icms/icms-api/templates/_helpers.tpl
• deploy/helm/icms/icms-api/values.versions.yaml
• deploy/helm/icms/icms-api/values.yaml

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