Let the RC attester read the lab's root-owned evidence

With the host-interface canary in place, v6.4.5-rc.4 passed the
schema-v7 systemd and rootful Docker lab (run 36594651903), but the
attestation step then failed with Permission denied on receipt.json,
which the privileged lab writes as root into the bind-mounted evidence
directory. Hand that directory to the runner user after a passing lab
and before attestation, without touching its content.

.github/workflows/qualify-secure-runtime-release.yml

@@ -331,6 +331,11 @@ jobs:
             --env "PULSE_SECURE_RUNTIME_TRANSCRIPT_RECORD_PATH=docs/release-control/v6/internal/records/secure-agent-runtime-systemd-transcript-v7-${TAG}.jsonl" \
             "${container}" \
             sh -c 'cd /workspace/scripts/installtests && exec /harness/installtests-linux-amd64.test -test.run "^TestSecureRuntimeSystemdDockerV7Lab$" -test.count=1 -test.v'
+          # The lab writes its receipt and transcript as root inside the
+          # privileged host. Hand the evidence directory to the runner user so
+          # the attester can read it and write the attestation beside it. The
+          # evidence content itself is not touched.
+          docker exec "${container}" chown -R "$(id -u):$(id -g)" /evidence
           elapsed="$(( $(date +%s) - start_epoch ))"
           if [[ "${elapsed}" -lt 1 ]]; then elapsed=1; fi
           echo "elapsed_seconds=${elapsed}" >> "$GITHUB_OUTPUT"

docs/release-control/v6/internal/subsystems/deployment-installability.md

@@ -1304,6 +1304,10 @@ artifact-selection behaviour.
    helper's private network isolation. Canary setup and the no-default-route
    check must fail qualification before that lab if the boundary is absent;
    they must not skip the lab or change the release packet under test.
+   The lab writes its receipt and transcript as root inside that container.
+   After a passing lab and before attestation, the workflow must hand the
+   evidence directory to the runner user without altering its content, so the
+   attester can read the receipt and write the attestation beside it.
    PVE jobs must consume their runner users' persistent local Go and npm caches
    directly; disposable-runner Actions cache restore/save phases must remain
    disabled because archiving those same caches adds network work after the

scripts/installtests/build_release_assets_test.go

@@ -2856,6 +2856,7 @@ func TestSecureRuntimeQualificationPacketIsHostedAndReleaseBound(t *testing.T) {
 		`ip link add pulse-can0 type veth peer name pulse-can1`,
 		`ip address add 192.0.2.1/32 dev pulse-can0`,
 		`test -z "$(ip -4 route show default)"`,
+		`docker exec "${container}" chown -R "$(id -u):$(id -g)" /evidence`,
 		`pulse-secure-runtime-fixture:v7`,
 		"--verify-release-packet-only",
 		"--verified-packet-dir",
@@ -2878,6 +2879,11 @@ func TestSecureRuntimeQualificationPacketIsHostedAndReleaseBound(t *testing.T) {
 	if canaryIndex <= privilegedExecutionIndex || labIndex <= canaryIndex {
 		t.Fatal("the isolated host-interface canary must be configured before running the immutable RC lab")
 	}
+	ownershipIndex := strings.Index(qualificationWorkflow, `docker exec "${container}" chown -R "$(id -u):$(id -g)" /evidence`)
+	attestIndex := strings.Index(qualificationWorkflow, `--output "${evidence_dir}/attestation.json"`)
+	if ownershipIndex <= labIndex || attestIndex <= ownershipIndex {
+		t.Fatal("the lab evidence must be handed to the runner user after the lab and before attestation")
+	}
 	if !strings.Contains(qualificationWorkflow, `--privileged \
             --network none \
             --cgroupns=host`) {