From 4f4da033b3c298fab56c7d21b38f734b092f7ccd Mon Sep 17 00:00:00 2001
From: Moritz Clasmeier <mclasmeier@redhat.com>
Date: Mon, 18 May 2026 13:26:29 +0200
Subject: [PATCH] Guard CI workflows against fork PRs provisioning
 infrastructure
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Add fork-origin checks to all jobs in pr.yml and docker-build.yml that
depend on repository secrets or provision real infrastructure (GKE and
OpenShift clusters via infractl).

The guard `github.event.pull_request.head.repo.full_name == github.repository`
ensures these jobs only run for PRs originating from the same repository,
not from external forks. This is defensive infrastructure practice for
public repositories because:

1. GitHub withholds repository secrets from fork PRs by design, so
   secret-dependent jobs (registry login, infra token auth, GCP SA)
   would fail anyway — but they fail late, after consuming CI minutes
   and producing confusing check statuses.

2. More critically, this prevents a future misconfiguration from becoming
   a security incident. If someone later changes the trigger from
   `pull_request` to `pull_request_target` (a common "fix" for the
   fork-secrets problem), the guard still blocks fork PRs from accessing
   INFRA_CI_TOKEN, ROXIE_CI_AUTOMATION_GCP_SA, and the ability to
   provision or delete GKE/OpenShift clusters on internal infrastructure.

3. Without the guard, fork PRs can trigger cluster creation attempts
   that fail with opaque auth errors, wasting time for both the
   contributor and reviewers trying to interpret the CI results.

For docker-build.yml, the guard additionally allows push events (tag
and branch pushes) to pass through unconditionally, since those are
not subject to the fork-PR threat model.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 .github/workflows/docker-build.yml |  1 +
 .github/workflows/pr.yml           | 10 +++++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/docker-build.yml b/.github/workflows/docker-build.yml
index 2fa98a5..16042b4 100644
--- a/.github/workflows/docker-build.yml
+++ b/.github/workflows/docker-build.yml
@@ -14,6 +14,7 @@ env:
 
 jobs:
   docker-build-push:
+    if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name == github.repository
     name: Build and Push Multi-arch Image
     runs-on: ubuntu-latest
     permissions:
diff --git a/.github/workflows/pr.yml b/.github/workflows/pr.yml
index 8da1082..126016b 100644
--- a/.github/workflows/pr.yml
+++ b/.github/workflows/pr.yml
@@ -29,6 +29,7 @@ jobs:
           fi
 
   create-gke-cluster:
+    if: github.event.pull_request.head.repo.full_name == github.repository
     uses: ./.github/workflows/create-dev-cluster.yml
     with:
       cluster-name: infra-roxie-pr-${{ github.event.pull_request.number }}-gke
@@ -38,7 +39,7 @@ jobs:
 
   create-openshift-cluster:
     needs: check-olm-label
-    if: needs.check-olm-label.outputs.has-label == 'true'
+    if: needs.check-olm-label.outputs.has-label == 'true' && github.event.pull_request.head.repo.full_name == github.repository
     uses: ./.github/workflows/create-dev-cluster.yml
     with:
       cluster-name: infra-roxie-pr-${{ github.event.pull_request.number }}-openshift
@@ -47,6 +48,7 @@ jobs:
     secrets: inherit
 
   build-roxie-image:
+    if: github.event.pull_request.head.repo.full_name == github.repository
     uses: ./.github/workflows/build-roxie-image.yml
     permissions:
       contents: read
@@ -54,6 +56,7 @@ jobs:
     secrets: inherit
 
   e2e-tests:
+    if: github.event.pull_request.head.repo.full_name == github.repository
     needs: [ create-gke-cluster, build-roxie-image ]
     uses: ./.github/workflows/e2e-tests.yml
     with:
@@ -62,6 +65,7 @@ jobs:
     secrets: inherit
 
   e2e-tests-openshift:
+    if: github.event.pull_request.head.repo.full_name == github.repository
     needs: [ create-openshift-cluster, build-roxie-image ]
     uses: ./.github/workflows/e2e-tests.yml
     with:
@@ -72,7 +76,7 @@ jobs:
     secrets: inherit
 
   delete-gke-cluster:
-    if: ${{ always() && needs.create-gke-cluster.result == 'success' }}
+    if: ${{ always() && needs.create-gke-cluster.result == 'success' && github.event.pull_request.head.repo.full_name == github.repository }}
     needs: [ create-gke-cluster, e2e-tests ]
     uses: ./.github/workflows/delete-dev-cluster.yml
     with:
@@ -80,7 +84,7 @@ jobs:
     secrets: inherit
 
   delete-openshift-cluster:
-    if: ${{ always() && needs.create-openshift-cluster.result == 'success' }}
+    if: ${{ always() && needs.create-openshift-cluster.result == 'success' && github.event.pull_request.head.repo.full_name == github.repository }}
     needs: [ create-openshift-cluster, e2e-tests-openshift ]
     uses: ./.github/workflows/delete-dev-cluster.yml
     with: