Codex v4 SILENT finding: my audit Finding-2 fix made the orphan-.bak branch emit
a state_db_deleted_webui_tombstone item, but the state_db_missing_rows loop still
emitted the same sid/kind again when both a surviving .json.bak AND a state.db row
exist for one deleted session — double-counting unsafe_to_repair, violating the
no-double-classification invariant. Fix: track _bak_tombstoned_ids from the .bak
branch and skip them in the state.db loop. Regression test
test_audit_no_double_count_when_bak_and_state_db_row_both_survive (verified fails
without the dedup).
Co-authored-by: rodboev <rodboev@users.noreply.github.com>
@rodboev independently pushed fixes for messaging-tombstone (matches ours) and an
audit orphan-.bak skip — but the audit skip used _marks_deleted_webui_session
(index heuristic), which re-introduces the crash-suppression bug, and the other 4
resurrection/recovery paths were still open. Rebuilt the stage on rodboev's new
head (fc21c3f3, attribution preserved) and applied the complete superset:
- routes.py claim path: tombstone 404 gated on _state_db_session_source in
('','webui','fork') so foreign-source rows always materialize (finding B)
- models.py sidebar projection: skip tombstoned source='webui' rows w/ no live
sidecar so a deleted session can't resurface in /api/sessions (finding C)
- session_recovery.py orphan-.bak startup: skip restore when durable tombstone
present, durable-only (finding D)
- session_recovery.py audit orphan-.bak: durable-only classify as
deleted_session_skipped (corrects rodboev's index-heuristic version)
- session_recovery.py _read_state_db_missing_sidecar_rows: durable-tombstone-only
so a genuine crash (index intact, no durable tombstone) still repairs (finding F)
Regression tests (all verified fail-without-fix): sidebar-projection, orphan-.bak
startup skip, messaging-not-tombstoned, index-only-crash-repairable. Both advisors
(Codex SAFE TO SHIP + Opus ship-with-fixes) cleared the prior stage; this rebuild
carries the same fixes onto the contributor's latest work.
Co-authored-by: rodboev <rodboev@users.noreply.github.com>
Two concrete data-corruption vectors flagged in Opus review of PR #2041,
both fixed atomically so the new repair-safe endpoint is safe for production:
1. Shared tmp filename under concurrent calls
`tmp = target.with_suffix('.json.reconcile.tmp')` produced a fixed path
per session ID. Two simultaneous repair-safe POSTs would interleave bytes
in the same tmp file, then both rename → corrupted JSON. Now matches the
`Session.save()` convention at api/models.py:484 with a pid+tid suffix.
2. TOCTOU between target.exists() check and tmp.replace(target)
`os.replace()` overwrites unconditionally. If a concurrent Session.save()
for the same SID materialized the live sidecar in the microsecond window
between the existence check and the rename, the reconciliation would
silently overwrite a live sidecar with a (lossier) state.db reconstruction.
Switched to `os.link()` + `unlink(tmp)` which is atomic create-or-fail —
on FileExistsError we record `skipped: sidecar_appeared_during_reconcile`
and keep the live sidecar untouched.
Plus a round-trip schema-parity test: materialize a sidecar from state.db,
then load it back through `Session.load()` and assert the messages survive.
Catches future schema drift between `_state_db_row_to_sidecar()` and
`Session.__init__()`. Also adds a guard test confirming the .reconcile.tmp
suffix includes pid+tid (regression guard for hazard #1).
Tests: 23 passing across the recovery suite (was 21; +2 new in this commit).
Co-authored-by: ai-ag2026 <261867348+ai-ag2026@users.noreply.github.com>
Rodrigo Gomes da Silva