fix(ci): harden GitHub Actions workflows (#14789)

.github/workflows/bot_pytest.yml

@@ -18,7 +18,25 @@ jobs:
       pull-requests: write
     outputs:
       comment_id: ${{ steps.comment.outputs.comment_id }}
+      authorized: ${{ steps.auth.outputs.authorized }}
     steps:
+      - name: Authorize commenter
+        id: auth
+        env:
+          AUTHOR_ASSOCIATION: ${{ github.event.comment.author_association }}
+          ACTOR: ${{ github.actor }}
+        run: |
+          case "$AUTHOR_ASSOCIATION" in
+            OWNER|MEMBER|COLLABORATOR)
+              echo "authorized=true" >> "$GITHUB_OUTPUT"
+              ;;
+            *)
+              echo "::error::User '${ACTOR}' (association: ${AUTHOR_ASSOCIATION}) is not authorized to trigger this workflow."
+              echo "authorized=false" >> "$GITHUB_OUTPUT"
+              exit 1
+              ;;
+          esac
+
       - name: Acknowledge with 👀
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -46,6 +64,7 @@ jobs:
   gpu:
     name: Run pytest on GPU
     needs: gate
+    if: ${{ needs.gate.outputs.authorized == 'true' }}
     # A newer command on the same PR supersedes an in-flight one. Scoped to this job
     # only so the superseded run's `report` still updates its comment.
     concurrency:
@@ -75,7 +94,7 @@ jobs:
         shell: bash
     steps:
       - name: Checkout PR head
-        uses: actions/checkout@v7
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           # Works for forks too — no fork credentials needed.
           ref: refs/pull/${{ github.event.issue.number }}/head
@@ -116,7 +135,7 @@ jobs:
 
       - name: Test suite reports artifacts
         if: ${{ always() }}
-        uses: actions/upload-artifact@v7.0.1
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: bot_gpu_test_reports
           path: reports
@@ -126,7 +145,7 @@ jobs:
     needs: [gate, gpu]
     # Always run so the comment is updated on success, failure, or cancellation —
     # but only if `gate` actually posted a comment to update.
-    if: ${{ always() && needs.gate.outputs.comment_id != '' }}
+    if: ${{ always() && needs.gate.outputs.authorized == 'true' && needs.gate.outputs.comment_id != '' }}
     runs-on: ubuntu-22.04
     permissions:
       pull-requests: write

.github/workflows/claude_review.yml

@@ -6,13 +6,15 @@ on:
   pull_request_review_comment:
     types: [created]
 
-permissions:
-  contents: write
-  pull-requests: write
-  issues: read
+
+permissions: {}
 
 jobs:
   claude-review:
+    permissions:
+      contents: write
+      issues: read
+      pull-requests: write
     if: |
       (
         github.event_name == 'issue_comment' &&
@@ -34,7 +36,7 @@ jobs:
       cancel-in-progress: false
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 #v7.0.1
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           fetch-depth: 1
 

.github/workflows/issue_labeler.yml

@@ -4,12 +4,14 @@ on:
   issues:
     types: [opened]
 
-permissions:
-  contents: read
-  issues: write
+
+permissions: {}
 
 jobs:
   label:
+    permissions:
+      contents: read
+      issues: write
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
@@ -22,7 +24,14 @@ jobs:
           ISSUE_TITLE: ${{ github.event.issue.title }}
           ISSUE_BODY: ${{ github.event.issue.body }}
         run: |
-          LABELS=$(python utils/label_issues.py)
+          # Issue title/body are untrusted user input: bound their length before
+          # they are handed to the LLM. utils/label_issues.py must wrap them in a
+          # clearly delimited user-content block and instruct the model to never
+          # follow instructions contained inside that block.
+          ISSUE_TITLE=$(printf '%s' "$ISSUE_TITLE" | head -c 500)
+          ISSUE_BODY=$(printf '%s' "$ISSUE_BODY" | head -c 4000)
+          export ISSUE_TITLE ISSUE_BODY
+          LABELS=$(python utils/label_issues.py | tr -d '\r\n')
           echo "labels=$LABELS" >> "$GITHUB_OUTPUT"
       - name: Apply labels
         if: steps.get-labels.outputs.labels != ''
@@ -31,6 +40,17 @@ jobs:
           ISSUE_NUMBER: ${{ github.event.issue.number }}
           LABELS: ${{ steps.get-labels.outputs.labels }}
         run: |
-          for label in $(echo "$LABELS" | python -c "import json,sys; print('\n'.join(json.load(sys.stdin)))"); do
-            gh issue edit "$ISSUE_NUMBER" --add-label "$label"
-          done
+          # The model output is untrusted (it can be steered by the issue author).
+          # Validate every returned label against a fixed server-side allowlist
+          # before mutating the issue with the write-scoped token.
+          ALLOWED_LABELS=$'bug\nenhancement\ndocumentation\nquestion\nfeature request\ngood first issue\nhelp wanted'
+          printf '%s' "$LABELS" \
+            | python -c "import json,sys; data=json.load(sys.stdin); data=data if isinstance(data,list) else []; print('\n'.join(str(x) for x in data[:10]))" \
+            | while IFS= read -r label; do
+                [ -n "$label" ] || continue
+                if ! printf '%s\n' "$ALLOWED_LABELS" | grep -Fxq -- "$label"; then
+                  echo "Skipping label not in allowlist: $label"
+                  continue
+                fi
+                gh issue edit "$ISSUE_NUMBER" --add-label "$label"
+              done

.github/workflows/mirror_community_pipeline.yml

@@ -69,13 +69,13 @@ jobs:
         run: |
           echo "CHECKOUT_REF: ${{ env.CHECKOUT_REF }}"
           echo "PATH_IN_REPO: ${{ env.PATH_IN_REPO }}"
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           ref: ${{ env.CHECKOUT_REF }}
 
       # Setup + install dependencies
       - name: Set up Python
-        uses: actions/setup-python@v7.0.0
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
         with:
           python-version: "3.10"
       - name: Install dependencies

.github/workflows/notify_slack_about_release.yml

@@ -13,10 +13,10 @@ jobs:
     runs-on: ubuntu-22.04
 
     steps:
-    - uses: actions/checkout@v7
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
     - name: Setup Python
-      uses: actions/setup-python@v7.0.0
+      uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
       with:
         python-version: '3.10'
 

.github/workflows/pr_dependency_test.yml

@@ -22,9 +22,9 @@ jobs:
   check_dependencies:
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Set up Python
-        uses: actions/setup-python@v7.0.0
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
         with:
           python-version: "3.10"
       - name: Install dependencies

.github/workflows/pr_labeler.yml

@@ -1,22 +1,27 @@
 name: PR Labeler
 
 on:
-  pull_request_target:
+  pull_request:
     types: [opened, synchronize, reopened]
 
-permissions:
-  contents: read
-  pull-requests: write
+
+permissions: {}
 
 jobs:
   label:
+    permissions:
+      contents: read
+      pull-requests: write
     runs-on: ubuntu-latest
     steps:
       - uses: actions/labeler@bf12e9b00b37c5c0ca2b87b79b2daf7891dbda13  # v7.0.0
         with:
           sync-labels: true
 
   missing-tests:
+    permissions:
+      contents: read
+      pull-requests: write
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
@@ -50,6 +55,9 @@ jobs:
           fi
 
   fixes-issue:
+    permissions:
+      issues: read
+      pull-requests: write
     runs-on: ubuntu-latest
     steps:
       - name: Check for linked closing issues
@@ -85,6 +93,8 @@ jobs:
           fi
 
   size-label:
+    permissions:
+      pull-requests: write
     runs-on: ubuntu-latest
     steps:
       - name: Label PR by diff size

.github/workflows/pr_modular_tests.yml

@@ -44,9 +44,9 @@ jobs:
   check_code_quality:
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Set up Python
-        uses: actions/setup-python@v7.0.0
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
         with:
           python-version: "3.10"
       - name: Install dependencies
@@ -64,9 +64,9 @@ jobs:
     needs: check_code_quality
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Set up Python
-        uses: actions/setup-python@v7.0.0
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
         with:
           python-version: "3.10"
       - name: Install dependencies
@@ -92,7 +92,7 @@ jobs:
     container:
       image: diffusers/diffusers-pytorch-cpu
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Install dependencies
         run: |
           printf 'torch==2.10.0\ntorchvision==0.25.0\ntorchaudio==2.10.0\n' > "$UV_OVERRIDE"
@@ -122,7 +122,7 @@ jobs:
 
     steps:
     - name: Checkout diffusers
-      uses: actions/checkout@v7
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with:
         fetch-depth: 2
 
@@ -151,7 +151,7 @@ jobs:
 
     - name: Test suite reports artifacts
       if: ${{ always() }}
-      uses: actions/upload-artifact@v7.0.1
+      uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
       with:
         name: pr_pytorch_pipelines_torch_cpu_modular_pipelines_test_reports
         path: reports

.github/workflows/pr_test_fetcher.yml

@@ -31,7 +31,7 @@ jobs:
       test_map: ${{ steps.set_matrix.outputs.test_map }}
     steps:
     - name: Checkout diffusers
-      uses: actions/checkout@v7
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with:
         fetch-depth: 0
     - name: Install dependencies
@@ -45,7 +45,7 @@ jobs:
       run: |
         python utils/tests_fetcher.py | tee test_preparation.txt
     - name: Report fetched tests
-      uses: actions/upload-artifact@v7.0.1
+      uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
       with:
         name: test_fetched
         path: test_preparation.txt
@@ -86,7 +86,7 @@ jobs:
         shell: bash
     steps:
     - name: Checkout diffusers
-      uses: actions/checkout@v7
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with:
         fetch-depth: 2
 
@@ -112,7 +112,7 @@ jobs:
 
     - name: Test suite reports artifacts
       if: ${{ always() }}
-      uses: actions/upload-artifact@v7.0.1
+      uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
       with:
           name: ${{ matrix.modules }}_test_reports
           path: reports
@@ -141,7 +141,7 @@ jobs:
 
     steps:
     - name: Checkout diffusers
-      uses: actions/checkout@v7
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with:
         fetch-depth: 2
 
@@ -167,7 +167,7 @@ jobs:
 
     - name: Test suite reports artifacts
       if: ${{ always() }}
-      uses: actions/upload-artifact@v7.0.1
+      uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
       with:
         name: pr_${{ matrix.config.report }}_test_reports
         path: reports