fix(provision): write managed hook scripts atomically at 0o755#143
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The hook writers wrote each script at mkstemp's 0600 default and set the exec bit in a SEPARATE chmod step — and omi-enforce.py never got a chmod at all. When a re-provision runs as root and the B2 guard-config hardening then chowns the hook to root, that 0600 window (or the never-widened enforce hook) is unreadable by the agent user, so `python3 omi-enforce.py` fails with EACCES mid-reprovision — the transient "the guard hook is dead" blip. Thread mode= through _write_managed/_write_if_absent into atomic_write_text (which already applies the mode to the temp file BEFORE the rename), and drop the separate post-rename dest.chmod(0o755) at all five hook sites. The destination is now never briefly at 0600. Adds a regression test asserting every provisioned hook is 0o755 (world-readable, so a chown-root can't render it unreadable). Full suite: 725 passed, 1 skipped; ruff clean. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01JFuGddPx3UhUkcC74KBXZB
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Atomic-0o755 hook provisioning fix (#143): managed hook scripts get their mode set on the temp file before the atomic rename, so a root-run re-provision never leaves a hook briefly at 0600 (unreadable by the agent user after the B2 chown-root) — the transient omi-enforce.py EACCES blip. Version 3.7.7 -> 3.7.8 (pyproject + __init__ + uv.lock); CHANGELOG. Full suite: 725 passed, 1 skipped; ruff clean. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01JFuGddPx3UhUkcC74KBXZB
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Summary
Fixes the transient "the guard hook is dead" blip:
python3 omi-enforce.pyfailing with EACCES right after a re-provision.Root cause: the managed-hook writers (
omi-enforce.py,omi-guard.sh,omi-gate-reset.sh,git-fresh-base.sh,secret-output-guard.sh) wrote each script atmkstemp's 0600 default and set the exec bit in a separatedest.chmod(0o755)step — andomi-enforce.pynever got a chmod at all.atomic_write_textalready applies amodeto the temp file before the rename, but the writers never passed one. So when a re-provision runs as root and the B2 hardening thenchowns the hook toroot, that 0600 window (or the never-widened enforce hook) is unreadable by the agent user -> EACCES.Fix: thread
mode=through_write_managed/_write_if_absentintoatomic_write_text, passmode=0o755at all five hook sites, and drop the now-redundant post-renamechmod. The destination lands 0755 atomically and is never briefly at 0600, so a subsequentchown rootcan't render it unreadable.Verification
ruff check .-> cleanpytest-> 725 passed, 1 skippedtest_managed_hook_scripts_are_written_0755_atomicallyasserts every provisioned hook is0o755(fails if a writer reverts to the bare 0600 write).Staged under
[Unreleased]; the version bump/tag is a separate batched release step.🤖 Generated with Claude Code
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