🤖 The Codex Security Review gate trusted GitHub's `author_association`
(`MEMBER`/`OWNER`), but GitHub only reports `MEMBER` to viewers who can
see the membership. The workflow `GITHUB_TOKEN` cannot see private
`block` org membership, which is GitHub's default, so most Block
employees read as `CONTRIBUTOR` and their PRs never reviewed
automatically. The same applied to the comment path, where private
members could not authorize a review with `@buzz-security-review <sha>`.
Trust is now repo write access, read from `GET
/repos/{owner}/{repo}/collaborators/{user}/permission` via
`getCollaboratorPermissionLevel`, which is independent of membership
visibility and works with the authorize job's existing `contents: read`
and `pull-requests: read` permissions. A user is trusted only when
`permission` is `write` (which includes `maintain`) or `admin`. A
successful lookup is not enough: on this public repository, an account
with no relationship to it returns `200` with `read`, not 404. Outside
contributors can only push to forks and come back `read`, so they still
need an explicit command from a trusted user.
The check covers the PR author on `pull_request_target`, the commenter
on `issue_comment` (the job-level `author_association` filter is removed
so the trusted script makes that decision), and the stale-marking path
on PR updates. Transient API errors are retried. Authorization fails
closed: any lookup error other than 404 fails the job instead of
authorizing. Stale-marking is conservative: an existing review is always
marked stale without consulting permissions, and a failed lookup counts
as untrusted, so a previous range's review can never appear current for
a new head. A commenter without write access is logged and ignored
instead of failing the run.
---------
Signed-off-by: Will Pfleger <pfleger.will@gmail.com>
Co-authored-by: Duncan <dcfd242e557282d7a1e2cf2e6877522682f1e5c6156dc92ca7d90eaedd3b0f95@buzz.block.builderlab.xyz>
The Codex security review workflow now authorizes automatic reviews from
the live pull request instead of the webhook snapshot. This prevents a
stale author association from sending an internal PR down the
external-contributor invalidation path.
Internal PRs with no previous review now exit without attempting a
comment or label mutation. The jobs that update PR comments and labels
use `pull-requests: write`, and the review job runs only after the
trusted prepare step emits `authorized=true`.
Regression tests cover stale author associations in both directions, the
no-op invalidation path, and the mutation-job permission contract.
Checked with `just ci`, `just security-review-check`, and `actionlint
.github/workflows/codex-security-review.yml`.
The failing `Mark Previous Review Stale` check on this PR runs the
pre-fix `pull_request_target` workflow from `main`. GitHub will not
execute this branch’s trusted workflow until it is merged; the new
workflow contract and state-machine tests exercise the fix before then.
Signed-off-by: Jordan Mecom <jm@squareup.com>
Add a gated Codex security review for Buzz pull requests.
Reviews run automatically for Block organization members. External PRs
require a `@buzz-security-review` comment from a Block member, and every
new external push invalidates the previous result.
Codex reviews the PR SHA in a read-only, network-restricted job with no
write GitHub token. A separate trusted job validates and sanitizes
structured findings before posting them. The workflow uses the dedicated
`CODEX_REVIEW_API_KEY` secret.
---------
Signed-off-by: Jordan Mecom <jm@squareup.com>
