fix(link): reject forged ss owner tuples before trusting a PID

[luvs01]

Summary

• parseListenEntriesFromSs attributed a listener's owner with a row-wide /pid=(\d+)/ match. ss -p prints comm unescaped inside quotes, so a crafted 15-byte task name can place a forged pid= field ahead of the real tuple — letting a local process make port reclaim / link-join logic blame (or kill) an innocent PID.
• The users:(...) column is now parsed strictly: quoted name consumed verbatim, then pid= plus only the keys ss actually emits in that position (fd, ino, sk, v6only). Any grammar deviation — an embedded second quote, an unknown key, trailing garbage — drops the row's attribution instead of trusting a partial parse. Rows without a users: column are still skipped; a genuinely shared socket still reports every owner tuple.

Verification

• bun test tests/server/port-reclaim.test.ts — 48 pass, 2 platform skips, including a new case feeding kernel-realistic rows for the crafted task names (embedded-quote forged pid, a complete forged tuple, forged in-tuple fields with both unknown and valid ss keys, trailing garbage after the column) — all dropped, while a real shared socket keeps both owners.
• bun x tsc --noEmit.

Checklist

• Scope stays focused and avoids unrelated cleanup.
• Docs or release notes were updated when needed.
• Security-sensitive changes were reviewed for secrets, auth, and unsafe defaults.

Summary by CodeRabbit

• Bug Fixes
  • Port detection now reads process IDs only from valid listener ownership fields, avoiding false matches from process names or malformed entries.
  • When a valid socket is shared, all associated process IDs are retained.

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📒 Files selected for processing (2)

• src/server/port-reclaim.ts
• tests/server/port-reclaim.test.ts

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📝 Walkthrough

Walkthrough

The ss listener parser now validates the full users: column before associating PIDs with a local address. It accepts listed owner fields, records all valid PIDs, and skips rows with missing or invalid owner data. Tests and documentation describe the updated parsing behavior.

Changes

ss owner parsing

Layer / File(s)	Summary
Validate and apply ss owner data src/server/port-reclaim.ts, tests/server/port-reclaim.test.ts, structure/remote-link.md	The parser validates the full users: column and accepts only the listed owner fields. It records each valid positive safe-integer PID and skips rows with missing or invalid owner data. Tests cover PID-like text in quoted process names, malformed owner data, and multiple owners. The documentation describes owner parsing outside the quoted process name.

Priority: ➖ Normal

Estimated code review effort: 2 (Simple) | ~12 minutes

Change: Bug fix

Suggested reviewers: wibias

Merge Risk: ⚪ Minimal · up to 7d50e

The examined forged process names do not cause another PID to be accepted as a listener owner. No actionable merge-blocking risk remains after normal checks.

Security Architecture Review

Security architecture risk: 🔵 Low · up to 7d50e

The stricter parser blocks forged owner IDs, and the client checks ownership again before sending its key. A malformed listener row can still leave an incomplete owner list, but a resulting key-exposure path depends on a concurrent listener configuration that has not been established.

Retained concerns

• Low · security · inferred: Dropping a malformed owner row without marking the scan incomplete can make a separate, valid tunnel row appear to be the sole listener. If a foreign listener can concurrently serve that loopback port, the unchanged readiness check could send the issued key despite incomplete attribution.

Security review details

Security Blast Radius

• inferred — The identified conditional exposure is local to listener attribution on the selected port, but the gated request carries an issued link API key. The available evidence does not establish that a foreign process can concurrently receive that request.

Security Findings and Attack Paths

• inferred — A malformed foreign-owner row can be omitted while a separate valid tunnel row remains. The readiness check would then see one reported PID; key exposure additionally requires the foreign listener to share or take the destination before the keyed request arrives.

Trust Boundaries and Controls

• observed — Strict tuple validation rejects malformed owner attribution. The consumer confines checks to listeners serving 127.0.0.1, requires the spawned PID alone, repeats the scan before transmitting the key, and does not follow redirects. Those controls substantially constrain the conditional path but do not establish that the reported owner set is complete.

Resilience and Maintainability Implications

• observed — Reclamation protects observed foreign or unverified live owners and defaults TCP-row dropping off outside Windows. An omitted malformed row is not represented as a failed scan, so that protection depends on whether another source reports the owner.

Hardening Proposals

• proposed — Consider distinguishing incomplete owner attribution from a complete empty scan wherever a singleton owner or absence of protected owners grants authority. Establish whether the deployed tunnel and a foreign listener can concurrently serve the selected port before treating the conditional key path as reachable.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: rejecting forged ss owner tuples before trusting their PIDs. It matches the parser hardening, related tests, and port-reclaim objective.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 3 functions across 2 files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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Actionable comments posted: 1

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• 🪄 Fix CodeRabbit comments on this PR

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Inline comments:
Review comments at @tests/server/port-reclaim.test.ts:
- Around line 166-167: Update the provenance comment above the crafted rows in
the test to describe them as synthetic adversarial inputs for the `ss` parser,
not as kernel output for 15-byte task names. Keep the existing fixture rows and
parser coverage unchanged.

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📥 Commits

Reviewing files that changed from the base of the PR and between 99a3b93 and 8e3ad33.

📒 Files selected for processing (3)

• src/server/port-reclaim.ts
• structure/remote-link.md
• tests/server/port-reclaim.test.ts

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[lidge-jun]

리뷰 · 우선순위 64 / 80

이 PR은 ss -p 출력에서 포트를 연 프로세스 번호를 고르는 방식을 바꿉니다. 예전 코드는 줄 전체에서 pid= 뒤의 숫자를 처음 본 것을 주인으로 삼았습니다. ss는 프로세스 이름을 따옴표 안에 바꾸지 않고 그대로 넣습니다. 이름은 15바이트까지입니다. 그 안에 따옴표와 pid=를 넣으면, 가짜 번호가 진짜 주인보다 앞에 섭니다. 포트 회수는 그 번호를 끝낼 수 있고, 링크 가입은 그 번호가 터널과 같으면 열쇠를 보낼 수 있습니다.

지금은 users:(...) 칸만 읽습니다. 이름은 따옴표 한 쌍이어야 하고, 바로 뒤에 pid=가 와야 합니다. 그 다음 칸은 fd, ino, sk, v6only만 허용합니다. 모양이 어긋나면 그 줄의 주인은 모두 버립니다. 소켓을 둘이 같이 쓰면 둘 다 남습니다. 빈 이름 ""는 거절합니다. 바탕 브랜치는 dev입니다. types.ts와 config.ts를 나누는 작업과 파일이 겹치지 않습니다. 같은 파서를 고치는 다른 열린 PR은 없습니다.

라인 - src/server/port-reclaim.ts parseSsOwnerPids. 주석은 가짜 튜플을 하나 더 넣으려면 ",pid=N,fd=N),("가 필요해서 15바이트 이름에는 안 들어간다고 적혀 있습니다. 파서는 fd가 없어도 튜플을 받습니다. 이름 a",pid=123),("b는 15바이트입니다. ss가 이 이름을 찍으면 users:(("a",pid=123),("b",pid=진짜,fd=4))가 됩니다. 이 함수는 [123, 진짜]를 돌려줍니다. 테스트는 빈 이름과 깨진 칸만 버리고, 이 15바이트 이름은 안 봅니다.

이 줄이 통과하면 링크 가입은 주인이 둘이므로 열쇠를 보내지 않습니다. 포트 회수는 목록의 번호를 하나씩 확인합니다. 123이 살아 있고 ocx로 확인되면, 포트를 연 프로세스가 아니어도 그 프로세스를 끝냅니다. 15바이트 안에서는 이렇게 붙는 가짜 번호가 999를 넘기 어렵습니다.

라인 - tests/server/port-reclaim.test.ts의 가짜 줄 주석. 그 문장은 커널이 그 줄을 찍는다고 합니다. 실제로 그 바이트는 ss가 이름을 따옴표 안에 넣어 만든 줄입니다.

메인테이너의 판단이 필요한 지점

지금 배포하는 ss는 튜플마다 fd=를 붙입니다. 파서도 튜플마다 fd=를 요구하면, 15바이트짜리 가짜 둘째 튜플은 문법에서 떨어집니다. fd 없이 pid만 찍는 오래된 ss가 있으면, 그 줄은 주인이 없는 줄로 버려집니다. 그 호환을 남길지는 여기서 정해야 합니다.

너의 추천

머지 전에 각 튜플에 fd=를 요구하세요. 테스트에 15바이트 이름 a",pid=123),("b를 넣고, 그 줄 전체가 버려지는지 확인하세요. 주석의 15바이트 설명도 그 조건과 맞추세요. 닫을 중복 PR은 없습니다.

이 댓글은 grok-bot이 작성했습니다

[Ingwannu]

Reviewed exact head 8e3ad33. The tuple parser still does not require fd= on each owner tuple. A real 15-byte Linux comm value such as a",pid=123),("b can make ss emit a users field shaped like users:(("a",pid=123),("b",pid=<real>,fd=...)); the parser accepts both the injected pid and the real listener pid. If the injected PID independently looks like an OpenCodex process, port reclaim may terminate it even though it does not own the socket.

Require each accepted owner tuple to contain its own fd= field, then add this exact 15-byte comm counterexample as a regression. Exact-head CI is green but does not cover this shape.

[Ingwannu]

Reviewed exact head 7d50ebbb9a46dcbf4f78351961fd18acadf27ac9. The previous blocker is fixed: every accepted owner tuple now requires its own fd=, hasFd resets per tuple, and any malformed later tuple rejects the row. The exact 15-byte embedded-quote forgery regression and shared-owner case are covered; exact-head four Linux shards and gates are green. No remaining P0-P2. Desktop shell is still running, so merge remains gated on aggregate CI completion. @lidge-jun please take the final pass after CI.

[luvs01]

Addressed the exact-head review finding: an owner tuple's pid= is no longer trusted without its own fd=.

• parseSsOwnerPids now requires every accepted owner tuple to carry its own fd= field before its pid= is attributed (src/server/port-reclaim.ts). A 15-byte comm such as a",pid=123),("b yields a first tuple whose pid= is present but fd= is absent, so the users: column is rejected rather than adopting the injected PID.
• Regression: added that exact counterexample - users:(("a",pid=123),("b",pid=<real>,fd=4)) is dropped and pid=123 never reaches the owner list (tests/server/port-reclaim.test.ts).
• Verified: bun test tests/server/port-reclaim.test.ts passes; typecheck clean.

New head: 7d50ebb