ci: clear the checkout token in every job that does not push (#5547)

actions/checkout writes its token into .git/config as an http extraheader,
where it stays for the rest of the job. That matters more here than usual:
pull_request jobs run on self-hosted runners and execute the PR's own build.rs,
proc-macros and tests, any of which can read that file. Test and Lint holds
actions: write on top of that, so its token can cancel runs and delete the
Actions caches the whole pipeline now depends on — it was given
persist-credentials: false when that permission was added, and this extends the
same treatment to the other 45 checkouts.

Two are exempt because the token IS the credential the job needs.
helm-package's publish job pushes to rustfs/helm with it; clearing it would
break chart publishing. nix-flake-update is exempt pending verification: it
passes FLAKE_UPDATE_TOKEN to create-pull-request directly rather than reusing
.git/config, so it very likely does not need persistence, but that is unproven
and a broken weekly bot is not worth the guess. Both carry a
persist-credentials-exempt comment saying which.

scripts/security/check_persist_credentials.sh requires every checkout to either
clear its credentials or carry that comment, so the decision stays visible in
review rather than being an omission nobody notices.

Refs: rustfs/backlog#1598, rustfs/backlog#1602

.github/workflows/architecture-migration-rules.yml

@@ -49,6 +49,8 @@ jobs:
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Install ripgrep
         run: |

.github/workflows/audit.yml

@@ -80,6 +80,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       # cargo-deny compiles nothing, so the full setup composite (apt packages,
       # protoc, flatc, nextest, rustfmt/clippy) was pure overhead here. It does
@@ -119,6 +121,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Report unpinned GitHub Actions
         run: ./scripts/security/check_workflow_pins.sh --enforce
@@ -129,6 +133,9 @@ jobs:
       - name: Check every job declares a timeout
         run: ./scripts/security/check_job_timeouts.sh
 
+      - name: Check checkouts clear their credentials
+        run: ./scripts/security/check_persist_credentials.sh
+
       - name: Check preview release workflow policy
         run: ./scripts/security/check_preview_release_workflow.sh
 
@@ -143,6 +150,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Dependency Review
         uses: actions/dependency-review-action@a1d282b36b6f3519aa1f3fc636f609c47dddb294 # v5
@@ -174,6 +183,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

.github/workflows/build.yml

@@ -99,6 +99,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Determine build strategy
         id: check
@@ -257,6 +259,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
         with:
+          persist-credentials: false
           fetch-depth: 0
 
       - name: Setup Rust environment
@@ -795,6 +798,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
         with:
+          persist-credentials: false
           fetch-depth: 0
 
       - name: Create GitHub Release
@@ -852,6 +856,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Download all build artifacts
         uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7

.github/workflows/ci-docs-only.yml

@@ -79,6 +79,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Install ripgrep
         run: sudo apt-get update && sudo apt-get install -y ripgrep
@@ -125,6 +127,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       # Docs-only PRs skip the full code CI, but they are exactly where a
       # planning-type document could be slipped in (git add -f bypasses

.github/workflows/ci.yml

@@ -95,6 +95,8 @@ jobs:
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Typos check with custom config file
         uses: crate-ci/typos@37bb98842b0d8c4ffebdb75301a13db0267cef89 # master
 
@@ -112,6 +114,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Install ripgrep
         run: sudo apt-get update && sudo apt-get install -y ripgrep
@@ -353,6 +357,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -391,6 +397,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -433,6 +441,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -461,6 +471,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -492,6 +504,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -532,6 +546,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -594,6 +610,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       # Full setup with dependency caching: the smoke-suite step below
       # compiles the e2e_test crate, which pulls in most of the workspace.
@@ -678,6 +696,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -721,6 +741,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Clean up previous test run
         run: |
@@ -775,6 +797,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Download debug binary
         uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7
@@ -847,6 +871,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Download debug binary
         uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7

.github/workflows/coverage.yml

@@ -62,6 +62,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -116,6 +118,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

.github/workflows/docker.yml

@@ -98,6 +98,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
         with:
+          persist-credentials: false
           # For workflow_run events, checkout the specific commit that triggered the workflow
           ref: ${{ github.event.workflow_run.head_sha || github.sha }}
 
@@ -305,6 +306,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Login to Docker Hub
         uses: docker/login-action@c94ce9fb468520275223c153574b00df6fe4bcc9 # v3

.github/workflows/e2e-replication-nightly.yml

@@ -64,6 +64,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -124,6 +126,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

.github/workflows/e2e-s3tests.yml

@@ -142,6 +142,8 @@ jobs:
       TEST_MODE: ${{ matrix.test-mode }}
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       # Provision Python explicitly rather than trusting the runner image to
       # ship a working pip (ci-1: a bare python3 without pip is what broke the
@@ -361,6 +363,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

.github/workflows/fuzz.yml

@@ -87,6 +87,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -152,6 +154,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Download prebuilt fuzz binaries
         uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7
@@ -207,6 +211,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Download prebuilt fuzz binaries
         uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7
@@ -254,6 +260,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

.github/workflows/helm-package.yml

@@ -50,6 +50,8 @@ jobs:
     steps:
       - name: Checkout helm chart repo
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       # Both inputs reach the shell through env rather than `${{ }}`
       # interpolation. A git ref name may contain `$(...)` — anything without a
@@ -121,6 +123,8 @@ jobs:
       - name: Checkout helm package repo
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
         with:
+          # persist-credentials-exempt: this checkout's token IS the push credential —
+          # the job git-pushes to rustfs/helm below. Clearing it breaks chart publishing.
           repository: rustfs/helm
           token: ${{ secrets.RUSTFS_HELM_PACKAGE }}
 

.github/workflows/minio-interop.yml

@@ -58,6 +58,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup

.github/workflows/mint.yml

@@ -125,6 +125,8 @@ jobs:
     timeout-minutes: 120
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Enable buildx
         uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3
@@ -270,6 +272,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

.github/workflows/nix-flake-update.yml

@@ -40,6 +40,10 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        # persist-credentials-exempt: update-flake-lock pushes the branch and opens
+        # the PR. It passes FLAKE_UPDATE_TOKEN to create-pull-request itself rather
+        # than reusing .git/config, but that is unverified — exempt until a
+        # workflow_dispatch run confirms it (rustfs/backlog#1602).
 
       - name: Install Nix
         uses: DeterminateSystems/determinate-nix-action@629b284231c2a82554b724e357e47fc6020833c8 # v3

.github/workflows/nix.yml

@@ -71,6 +71,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Install Nix
         uses: DeterminateSystems/determinate-nix-action@4eea0b33e3d1f02ecfe37cf16e7204c424009606 # v3.21.0

.github/workflows/performance-ab.yml

@@ -99,6 +99,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
 
       - name: Setup Rust environment
         uses: ./.github/actions/setup
@@ -148,6 +150,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
         with:
+          persist-credentials: false
           fetch-depth: 0 # baseline is built from origin/main
 
       - name: Setup Rust environment
@@ -394,6 +397,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

.github/workflows/schedule-failure-alert-drill.yml

@@ -63,6 +63,8 @@ jobs:
       issues: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          persist-credentials: false
       - name: Open or update failure-tracking issue
         uses: ./.github/actions/schedule-failure-issue
         with:

scripts/security/check_persist_credentials.sh

@@ -0,0 +1,72 @@
+#!/usr/bin/env bash
+# Every actions/checkout must set persist-credentials: false, or carry an
+# explicit exemption comment.
+#
+# By default checkout writes its token into .git/config as an http extraheader,
+# where it stays for the rest of the job. On this repository that matters more
+# than usual: pull_request jobs run on self-hosted runners and execute the PR's
+# own build.rs, proc-macros and tests, any of which can read that file. The
+# Test and Lint job additionally holds actions: write, so its token can cancel
+# runs and delete the Actions caches the whole pipeline depends on.
+#
+# A checkout is exempt only when the token IS the credential the job needs —
+# helm-package pushes to rustfs/helm with it. Mark those with a comment
+# containing `persist-credentials-exempt` inside the step, so the decision is
+# visible in review instead of being an omission.
+#
+# Usage: scripts/security/check_persist_credentials.sh
+set -euo pipefail
+
+cd "$(dirname "$0")/../.."
+
+status=0
+
+for file in .github/workflows/*.yml .github/workflows/*.yaml .github/actions/*/action.yml; do
+    [ -e "$file" ] || continue
+
+    awk -v file="$file" '
+        function flush() {
+            if (pending && !found_pc && !found_exempt) {
+                printf "%s:%d: actions/checkout without `persist-credentials: false`\n", file, checkout_line > "/dev/stderr"
+                bad++
+            }
+            pending = 0; found_pc = 0; found_exempt = 0
+        }
+        {
+            line = $0
+            sub(/[[:space:]]+$/, "", line)
+            if (line ~ /^[[:space:]]*$/) next
+
+            match(line, /^[[:space:]]*/)
+            indent = RLENGTH
+
+            if (line ~ /uses:[[:space:]]*actions\/checkout@/) {
+                flush()
+                pending = 1
+                # `- uses:` puts the step keys two columns right of the dash.
+                checkout_indent = (line ~ /^[[:space:]]*- /) ? indent + 2 : indent
+                checkout_line = NR
+                next
+            }
+
+            if (!pending) next
+            if (indent < checkout_indent) { flush(); next }
+            if (line ~ /persist-credentials:/) found_pc = 1
+            if (line ~ /persist-credentials-exempt/) found_exempt = 1
+        }
+        END { flush(); exit (bad > 0) }
+    ' "$file" || status=1
+done
+
+if [ "$status" -ne 0 ]; then
+    echo "" >&2
+    echo "Add to each checkout above:" >&2
+    echo "        with:" >&2
+    echo "          persist-credentials: false" >&2
+    echo "" >&2
+    echo "If the job genuinely needs the token to push, keep it and say why in a" >&2
+    echo "comment containing 'persist-credentials-exempt'. See rustfs/backlog#1602." >&2
+    exit 1
+fi
+
+echo "OK: every actions/checkout clears its credentials or is explicitly exempt"