fix(agent-team): harden github intake per /sh-security-review (CWE-918, idempotency)

Fixes from the high-recall detector fan-out on the durable-dedup change:

- INTAKE-LOGIC-01 (idempotency): switch the IngestStore seam from
  check-then-record (seen/mark) to claim-then-do (claim/release). The id is
  now reserved BEFORE the non-idempotent start_task side effect, so a crash in
  that window cannot re-spawn a duplicate task on the next run; a raising
  start_task releases the claim so transient failures stay retryable. Adds
  delete_issue_ingested to the schema layer for the release path.
- INTAKE-SSRF-001 / INTAKE-PATHSPLICE-002 (CWE-918) in build_default_issue_client:
  drop the caller-overridable api_root (hardcode GITHUB_API_ROOT) and validate
  owner/repo against an anchored charset before splicing them into the
  token-bearing API URL — mirrors the sibling ci_fetcher BLOCK-3/FIX-3 fixes.

Tests cover cross-process duplicate prevention, release-on-failure retry, and
the owner/repo + api_root rejection. 982 tests pass, ruff clean.

Follow-up (pre-existing, not introduced here): the label-only intake has no
author allowlist (cf. AGENT_TEAM_SLACK_OWNER_IDS on the Slack listener); the
Slack answer gate bounds the blast radius. Track as separate hardening.
This commit is contained in:
Adam Moussa 2026-06-22 17:06:56 -04:00
parent 3c8317b06e
commit ebc350aee5
3 changed files with 190 additions and 41 deletions

View file

@ -37,6 +37,7 @@ __all__ = [
"QUESTION_STATES",
"answer_question",
"connect",
"delete_issue_ingested",
"expire_question",
"find_open_question_by_channel_ref",
"init_db",
@ -311,6 +312,22 @@ def record_issue_ingested(
return cur.rowcount > 0
def delete_issue_ingested(
conn: sqlite3.Connection, *, source: str, issue_id: str
) -> bool:
"""Undo a recorded ingest of ``(source, issue_id)``; True if a row was removed.
Used to RELEASE a claim made via :func:`record_issue_ingested` when the
downstream intake (``start_task``) raises, so a transiently-failed issue
stays eligible for retry on the next poll rather than being silently dropped.
"""
cur = conn.execute(
"DELETE FROM ingested_issues WHERE source = ? AND issue_id = ?",
(source, issue_id),
)
return cur.rowcount > 0
def answer_question(
conn: sqlite3.Connection,
*,

View file

@ -36,8 +36,11 @@ De-duplication:
run and spawn duplicate tasks. The box is read-only (no write token to
remove the intake label), so durable de-dup is the only correct guard.
The id is recorded only AFTER ``start_task`` returns, so a failing intake
leaves the issue eligible for retry on the next poll rather than a silent drop.
The poller uses **claim-then-do**: it reserves the id on the store BEFORE
the non-idempotent ``start_task`` call, and releases the claim if that call
raises. So a transient failure stays retryable, a re-run never double-spawns,
and only a hard crash in the (tiny) window between claim and call drops the
issue — the safe failure for a read-only source whose label persists.
Design constraints honoured here (pre-deployment scaffolding):
* **No live infrastructure.** Nothing is provisioned or called at import.
@ -56,6 +59,7 @@ Design constraints honoured here (pre-deployment scaffolding):
from __future__ import annotations
import logging
import re
from typing import Any, Iterable, Protocol
__all__ = [
@ -77,6 +81,17 @@ GITHUB_TRANSPORT_NAME = "github"
# time (never stored in source/state). Mirrors the github_adapter default.
DEFAULT_TOKEN_ENV = "GITHUB_TOKEN"
# The GitHub REST host, HARDCODED (mirrors ci_fetcher FIX-3): the production
# client does NOT accept a caller-overridable api_root, so a token-bearing GET
# can never be redirected at an attacker host / file:// (CWE-918).
GITHUB_API_ROOT = "https://api.github.com"
# owner/repo are spliced into the API URL path; validate them (anchored) before
# URL construction so a crafted owner/repo cannot splice extra path/query
# segments or traversal into the authenticated request (mirrors ci_fetcher's
# _OWNER_REPO_RE / BLOCK-3). GitHub logins and repo names are a subset of this.
_OWNER_REPO_RE = re.compile(r"[A-Za-z0-9_.-]{1,100}")
class GithubIssueClient(Protocol):
"""Injected GitHub issue source: list open issues carrying a label.
@ -98,21 +113,27 @@ class IngestStore(Protocol):
A narrow seam so the poller's de-dup is swappable: a per-process in-memory
set for tests/one-off runs, or the durable SQLite ledger store for a
scheduled intake (see the module docstring). ``seen``/``mark`` mirror the
check-then-record discipline; ``snapshot`` exposes the current id set for
introspection/logging.
scheduled intake (see the module docstring).
The contract is **claim-then-do** (not check-then-record): :meth:`claim`
atomically reserves an id and reports whether THIS caller won the claim, so
the id is reserved BEFORE the (non-idempotent) ``start_task`` side effect
runs — closing the window where a crash between starting a task and recording
the id would re-spawn a duplicate. :meth:`release` undoes a claim when
``start_task`` raises, keeping a transiently-failed issue retryable.
"""
def seen(self, issue_id: str) -> bool:
"""Return True if ``issue_id`` has already been ingested."""
def claim(self, issue_id: str) -> bool:
"""Atomically reserve ``issue_id``. True if newly claimed (caller should
ingest); False if already claimed/ingested (caller skips)."""
...
def mark(self, issue_id: str) -> None:
"""Record ``issue_id`` as ingested (idempotent)."""
def release(self, issue_id: str) -> None:
"""Undo a claim so the issue is retryable (used when ``start_task`` raises)."""
...
def snapshot(self) -> frozenset[str]:
"""Return a read-only snapshot of the ingested ids."""
"""Return a read-only snapshot of the claimed/ingested ids."""
...
@ -127,11 +148,14 @@ class _InMemoryIngestStore:
def __init__(self) -> None:
self._ids: set[str] = set()
def seen(self, issue_id: str) -> bool:
return issue_id in self._ids
def mark(self, issue_id: str) -> None:
def claim(self, issue_id: str) -> bool:
if issue_id in self._ids:
return False
self._ids.add(issue_id)
return True
def release(self, issue_id: str) -> None:
self._ids.discard(issue_id)
def snapshot(self) -> frozenset[str]:
return frozenset(self._ids)
@ -248,17 +272,20 @@ class GithubIntake:
1. Ask the injected client for the open issues carrying the configured
label (:meth:`GithubIssueClient.list_open_issues`).
2. For each issue NOT already in the in-memory ingested set, call
2. For each issue, **claim** its id on the store first
(:meth:`IngestStore.claim`); if the claim is lost (already
claimed/ingested) the issue is skipped. Only the winning claim calls
``coordinator.start_task(task_text=<title+body>,
transport_name="github")`` and record its id so a subsequent poll
does not re-ingest it.
transport_name="github")``.
Issues already ingested this process are skipped (the in-memory de-dup),
and any issue the client returns without the label is *not* expected
(the client filters by label) but is ignored defensively if present.
An issue id is recorded as ingested ONLY after ``start_task`` returns,
so a failing intake leaves the issue eligible for retry on the next poll
rather than silently dropping it.
Claim-then-do (not record-after): the id is reserved BEFORE the
non-idempotent ``start_task`` side effect, so a crash between starting
the task and finishing the pass cannot re-spawn a duplicate on the next
run. If ``start_task`` *raises*, the claim is RELEASED so a transient
failure stays retryable (no silent drop). The only residual is a hard
crash (SIGKILL/OOM/reboot) between the claim and the call, which drops
the issue rather than duplicating it — the safer failure for a read-only
source whose label persists for an operator to re-trigger.
Returns the list of issue ids ingested on THIS pass (empty when nothing
new), so an operator loop can log/meter intake volume.
@ -266,7 +293,7 @@ class GithubIntake:
ingested_now: list[str] = []
for issue in self._client.list_open_issues(label=self._label):
issue_id = _issue_id(issue)
if self._store.seen(issue_id):
if not self._store.claim(issue_id):
_LOG.debug("github-intake: issue %s already ingested; skip", issue_id)
continue
@ -276,15 +303,18 @@ class GithubIntake:
issue_id,
self._label,
)
# start_task is the committed coordinator intake entry; the resulting
# task's clarifier question-sets route over the GitHub adapter. Record
# the id only after the call returns so a raise leaves the issue
# eligible for retry on the next poll (no silent drop).
self._coordinator.start_task(
task_text=task_text,
transport_name=GITHUB_TRANSPORT_NAME,
)
self._store.mark(issue_id)
# The claim above reserved the id BEFORE this non-idempotent intake
# call (coordinator.start_task mints a fresh thread + an open question
# row). On a raise, RELEASE the claim so the transient failure is
# retryable on the next poll rather than a silent drop.
try:
self._coordinator.start_task(
task_text=task_text,
transport_name=GITHUB_TRANSPORT_NAME,
)
except Exception:
self._store.release(issue_id)
raise
ingested_now.append(issue_id)
return ingested_now
@ -295,7 +325,6 @@ def build_default_issue_client(
owner: str,
repo: str,
token_env: str = DEFAULT_TOKEN_ENV,
api_root: str = "https://api.github.com",
) -> GithubIssueClient:
"""Build the production read-only issue client (deferred SDK/HTTP import).
@ -307,8 +336,15 @@ def build_default_issue_client(
unit tests (which inject a fake client) never reach this path.
The token is read from ``token_env`` at call time and sent as a bearer
credential; it is never stored in source or logged. ``api_root`` is
overridable for GitHub Enterprise.
credential; it is never stored in source or logged.
Security (mirrors ci_fetcher BLOCK-3 / FIX-3, CWE-918): the GitHub host is
HARDCODED (:data:`GITHUB_API_ROOT`) — there is no caller-overridable
``api_root``, so the token-bearing GET can never be redirected at an
attacker host or ``file://``. ``owner`` and ``repo`` are validated against
an anchored charset (:data:`_OWNER_REPO_RE`) BEFORE being spliced into the
URL path, failing closed so a crafted value cannot inject extra path/query
segments or traversal.
This is intentionally a thin, read-only lister: it issues a single GET to
the issues endpoint with ``state=open&labels=<label>`` and returns the
@ -316,6 +352,12 @@ def build_default_issue_client(
already carries ``id`` / ``number`` / ``title`` / ``body``). It performs no
CI, OIDC, write, or GitHub-Actions call; it only reads issues.
"""
for _field, _value in (("owner", owner), ("repo", repo)):
if not _OWNER_REPO_RE.fullmatch(_value):
raise ValueError(
f"invalid GitHub {_field} {_value!r}: must match "
f"{_OWNER_REPO_RE.pattern} (refusing to build an unsafe API URL)"
)
class _RestIssueClient:
"""Stdlib-only GitHub REST issue lister (built lazily, no import-time HTTP)."""
@ -324,7 +366,8 @@ def build_default_issue_client(
self._owner = owner
self._repo = repo
self._token_env = token_env
self._api_root = api_root.rstrip("/")
# Hardcoded host (no overridable api_root); owner/repo already validated.
self._api_root = GITHUB_API_ROOT
def list_open_issues(self, *, label: str) -> Iterable[dict[str, Any]]:
import json
@ -391,13 +434,16 @@ def build_ledger_ingest_store(*, db_path: Any, source: str) -> IngestStore:
# not been init_db'd yet (idempotent CREATE IF NOT EXISTS).
self._conn.execute(_schema.INGESTED_ISSUES_DDL)
def seen(self, issue_id: str) -> bool:
return _schema.issue_already_ingested(
def claim(self, issue_id: str) -> bool:
# INSERT OR IGNORE under the (source, issue_id) primary key: returns
# True only if THIS call inserted the row (won the claim), so two
# concurrent pollers or a re-run can never both ingest the same issue.
return _schema.record_issue_ingested(
self._conn, source=self._source, issue_id=issue_id
)
def mark(self, issue_id: str) -> None:
_schema.record_issue_ingested(
def release(self, issue_id: str) -> None:
_schema.delete_issue_ingested(
self._conn, source=self._source, issue_id=issue_id
)

View file

@ -17,6 +17,7 @@ import pytest
from agent_team.transport.github_intake import (
GITHUB_TRANSPORT_NAME,
GithubIntake,
build_default_issue_client,
build_ledger_ingest_store,
issue_task_text,
)
@ -304,3 +305,88 @@ def test_durable_store_namespaces_by_source(tmp_path: Path) -> None:
def test_build_ledger_ingest_store_rejects_empty_source(tmp_path: Path) -> None:
with pytest.raises(ValueError):
build_ledger_ingest_store(db_path=tmp_path / "x.sqlite", source="")
# --------------------------------------------------------------------------- #
# Claim-then-do durability (INTAKE-LOGIC-01 fix) + client hardening
# --------------------------------------------------------------------------- #
def test_durable_claim_without_release_prevents_duplicate(tmp_path: Path) -> None:
"""Claim-then-do: a claim recorded but never released (a crash around
start_task) must NOT re-ingest on a fresh process — no duplicate task."""
db = tmp_path / "ledger.sqlite"
source = "github:o/r"
# Simulate a poller that won the claim then 'crashed' before releasing.
store1 = build_ledger_ingest_store(db_path=db, source=source)
assert store1.claim("42") is True
assert store1.claim("42") is False # same store: re-claim loses
# Fresh process over the same DB: the claim persists, so poll skips it.
store2 = build_ledger_ingest_store(db_path=db, source=source)
coord = FakeCoordinator()
intake = GithubIntake(
client=FakeIssueClient([_issue(42)]),
coordinator=coord,
label=INTAKE_LABEL,
store=store2,
)
assert intake.poll_once() == []
assert coord.calls == []
def test_failed_start_task_releases_durable_claim_for_retry(tmp_path: Path) -> None:
"""A raising start_task releases the durable claim so a later poll retries."""
db = tmp_path / "ledger.sqlite"
source = "github:o/r"
class FlakyCoordinator:
def __init__(self) -> None:
self.attempts = 0
def start_task(self, *, task_text: str, transport_name: str) -> str:
self.attempts += 1
if self.attempts == 1:
raise RuntimeError("transient intake failure")
return "thread-ok"
coord = FlakyCoordinator()
intake = GithubIntake(
client=FakeIssueClient([_issue(1)]),
coordinator=coord,
label=INTAKE_LABEL,
store=build_ledger_ingest_store(db_path=db, source=source),
)
with pytest.raises(RuntimeError):
intake.poll_once()
# The claim was released, so a fresh process sees the issue as unclaimed.
intake2 = GithubIntake(
client=FakeIssueClient([_issue(1)]),
coordinator=coord,
label=INTAKE_LABEL,
store=build_ledger_ingest_store(db_path=db, source=source),
)
assert intake2.poll_once() == ["1"]
assert coord.attempts == 2
def test_build_default_issue_client_rejects_unsafe_owner_repo() -> None:
"""owner/repo are validated before URL construction (path-splice / CWE-918)."""
with pytest.raises(ValueError):
build_default_issue_client(owner="../../..", repo="r")
with pytest.raises(ValueError):
build_default_issue_client(owner="o", repo="r/issues?labels=admin")
with pytest.raises(ValueError):
build_default_issue_client(owner="", repo="r")
# A normal owner/repo builds fine.
client = build_default_issue_client(
owner="Sea-Haven-Industries", repo="orchestrator"
)
assert hasattr(client, "list_open_issues")
def test_build_default_issue_client_rejects_api_root_kwarg() -> None:
"""No caller-overridable api_root (SSRF/host-redirect, mirrors ci_fetcher FIX-3)."""
with pytest.raises(TypeError):
build_default_issue_client(owner="o", repo="r", api_root="https://evil.example")