🛡️ Sentinel: [HIGH] 원자적 파일 이동(Atomic Move)을 통한 Race Condition 방지

[seonghobae]

🚨 Severity: HIGH
💡 Vulnerability: 파일 쓰기 시 임시 파일(tempPath)에서 최종 대상(indexPath)으로 파일을 이동할 때 원자적 이동(ATOMIC_MOVE)을 사용하지 않아, 파일 교체 도중 다른 프로세스나 웹 서버에서 불완전한 상태의 index.html을 읽게 될 수 있는 Race Condition(경쟁 상태)이 존재했습니다.
🎯 Impact: 이로 인해 사용자가 손상되거나 불완전한 디렉토리 인덱스 HTML을 보게 되며, 특정 상황에서는 의도치 않은 파일 상태가 노출되어 무결성이 훼손될 수 있습니다.
🔧 Fix: Files.move 수행 시 StandardCopyOption.ATOMIC_MOVE 옵션을 사용하는 atomic_move 래퍼 함수를 도입했습니다. 만약 대상 파일 시스템이 이를 지원하지 않아 AtomicMoveNotSupportedException이 발생하면 기존 방식인 REPLACE_EXISTING으로 우아하게 폴백(Fallback)하도록 처리했습니다.
✅ Verification: 100% 테스트 커버리지를 위해 atomic_move 함수 호출과 Exception 폴백 상황을 모두 검증하는 단위 테스트(AtomicMoveTest2.kt)를 추가하여 jacocoTestCoverageVerification을 통과함을 확인했습니다.

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PR created automatically by Jules for task 2084004960696294969 started by @seonghobae

[google-labs-jules]

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[opencode-agent]

Pull request overview

OpenCode cannot approve yet because required coverage evidence did not pass.

Review outcome

1. HIGH .github/workflows/opencode-review.yml:1 - Coverage evidence did not prove required test/docstring evidence

• Problem: The required coverage-evidence job result was failure, so OpenCode cannot establish approval sufficiency for this head.

• Root cause: Automated approval is only valid when the same-head coverage-evidence job proves supported repository test suites passed and configured docstring gates passed or were advisory, or reports not applicable because no supported source files or package manifests exist. Missing, failed, skipped, unavailable, or unsupported-tooling test evidence is a blocker.

• Fix: Install or configure the repository test/docstring evidence tooling when source files or package manifests exist, rerun the current-head coverage-evidence job, and approve only after it reports success with required evidence or explicit no-source not-applicable evidence.

• Regression test: Keep the approval branch checking needs.coverage-evidence.result == success before posting APPROVE, and publish REQUEST_CHANGES when coverage-evidence blocker states such as cancelled, skipped, failed, unsupported-tooling, or below-100 evidence are present.

• Result: REQUEST_CHANGES

• Reason: coverage-evidence result was failure, so required test/docstring evidence was not proven for current head dad22f8de441244a4656f4ff62b341c55672e640.

• Head SHA: dad22f8de441244a4656f4ff62b341c55672e640

• Workflow run: 30424171192

• Workflow attempt: 1

Coverage evidence

Coverage evidence job did not run or did not publish coverage evidence.

Changed-File Evidence Map

flowchart LR
  PR["PR changed files"] --> Evidence["OpenCode bounded evidence"]
  Evidence --> S1["Changed file (3 files)"]
  S1 --> I1["repository behavior"]
  I1 --> R1["Review risk: Changed file (3 files)"]
  R1 --> V1["required checks"]

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[opencode-agent]

OpenCode Review Overview

• Head SHA: dad22f8de441244a4656f4ff62b341c55672e640
• Workflow run: 30424171192
• Workflow attempt: 1
• Gate result: REQUEST_CHANGES (approval step)

Pull request overview

OpenCode cannot approve yet because required coverage evidence did not pass.

Review outcome

1. HIGH .github/workflows/opencode-review.yml:1 - Coverage evidence did not prove required test/docstring evidence

• Problem: The required coverage-evidence job result was failure, so OpenCode cannot establish approval sufficiency for this head.

• Root cause: Automated approval is only valid when the same-head coverage-evidence job proves supported repository test suites passed and configured docstring gates passed or were advisory, or reports not applicable because no supported source files or package manifests exist. Missing, failed, skipped, unavailable, or unsupported-tooling test evidence is a blocker.

• Fix: Install or configure the repository test/docstring evidence tooling when source files or package manifests exist, rerun the current-head coverage-evidence job, and approve only after it reports success with required evidence or explicit no-source not-applicable evidence.

• Regression test: Keep the approval branch checking needs.coverage-evidence.result == success before posting APPROVE, and publish REQUEST_CHANGES when coverage-evidence blocker states such as cancelled, skipped, failed, unsupported-tooling, or below-100 evidence are present.

• Result: REQUEST_CHANGES

• Reason: coverage-evidence result was failure, so required test/docstring evidence was not proven for current head dad22f8de441244a4656f4ff62b341c55672e640.

• Head SHA: dad22f8de441244a4656f4ff62b341c55672e640

• Workflow run: 30424171192

• Workflow attempt: 1

Coverage evidence

Coverage evidence job did not run or did not publish coverage evidence.

Changed-File Evidence Map

flowchart LR
  PR["PR changed files"] --> Evidence["OpenCode bounded evidence"]
  Evidence --> S1["Changed file (3 files)"]
  S1 --> I1["repository behavior"]
  I1 --> R1["Review risk: Changed file (3 files)"]
  R1 --> V1["required checks"]

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[seonghobae]

Closing as superseded by draft canonical #296. The same atomic move and unsupported-filesystem fallback intent is retained there, but #296 avoids overstating the fallback as eliminating every race/TOCTOU risk and defines the required post-#363 update, deterministic publication/failure tests, complete JaCoCo branches, KDoc, APA 7 doctoring, changelog, exact-head checks, and independent approval. No evidence from this duplicate head is reused.

[google-labs-jules]

Closing as superseded by draft canonical #296. The same atomic move and unsupported-filesystem fallback intent is retained there, but #296 avoids overstating the fallback as eliminating every race/TOCTOU risk and defines the required post-#363 update, deterministic publication/failure tests, complete JaCoCo branches, KDoc, APA 7 doctoring, changelog, exact-head checks, and independent approval. No evidence from this duplicate head is reused.

Understood. Acknowledging that this work is now obsolete and stopping work on this task.