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Author SHA1 Message Date
Ben
4f416fc40c fix(docker): make s6 lifecycle work for the unprivileged hermes user
Resolves the explicit "Known follow-up" left by commit 2f8ceeab9 and
the resulting CI failures in tests/docker/test_dashboard.py and
tests/docker/test_s6_profile_gateway_integration.py.

The product gap
---------------
Every hermes runtime operation inside the container runs as the
hermes user (UID 10000) via s6-setuidgid. But s6-supervise — spawned
by s6-svscan running as PID 1 — creates each service's supervise/
and top-level event/ directories with mode 0700 owned by its
effective UID (root). That left every s6-svc / s6-svstat / s6-svwait
call from hermes hitting EACCES on the supervise/control FIFO and
supervise/status — i.e. the entire S6ServiceManager lifecycle
(register, start, stop, unregister) was inert in production.

The 2f8ceeab9 commit message called this out and deferred the fix.
The audit changes that landed alongside it (defaulting docker_exec
to -u hermes) made the integration tests reproduce the bug
deterministically; the fix below resolves it.

The fix: pre-create the supervise/ skeleton hermes-owned
----------------------------------------------------------
Reading s6's source (src/supervision/s6-supervise.c::trymkdir +
control_init), the mkdir and mkfifo calls that build the supervise
tree are EEXIST-safe: if the directory or FIFO is already present,
s6-supervise reuses it and skips the chown/chmod fix-up that would
normally make event/ 03730 root:root. So if we lay the skeleton
down with hermes ownership before triggering s6-svscanctl -a,
s6-supervise inherits our layout and never touches it. The
death_tally / lock / status regular files written later by
s6-supervise (still as root) land mode 0644 — world-readable —
which is all s6-svstat needs.

New module-level helper _seed_supervise_skeleton(svc_dir) in
hermes_cli/service_manager.py lays down:
  svc_dir/event/                       hermes:hermes 03730
  svc_dir/supervise/                   hermes:hermes 0755
  svc_dir/supervise/event/             hermes:hermes 03730
  svc_dir/supervise/control            hermes:hermes 0660 (FIFO)
  svc_dir/log/event/                   hermes:hermes 03730  (if log/ present)
  svc_dir/log/supervise/               hermes:hermes 0755
  svc_dir/log/supervise/event/         hermes:hermes 03730
  svc_dir/log/supervise/control        hermes:hermes 0660 (FIFO)

The log/ branch matters because the logger is a second
s6-supervise instance — without it, unregister rmtree races on
the logger's root-owned supervise dir even after the parent
slot's supervise/ is hermes-owned. The helper is idempotent and
swallows PermissionError on chown so it works equally well when
called from root (cont-init.d) or hermes (runtime register).

Wiring
------
1. S6ServiceManager.register_profile_gateway calls
   _seed_supervise_skeleton(tmp_dir) just before publishing the
   slot via Path.replace. Runtime-registered profile gateways are
   set up by hermes.

2. container_boot._register_service does the same in the cont-init.d
   reconciliation path so boot-time-restored profile slots inherit
   the same layout.

3. New cont-init.d/015-supervise-perms script chowns the supervise/
   and event/ trees for STATIC s6-rc services (dashboard,
   main-hermes). These are spawned by s6-rc before cont-init.d
   gets to run, so the EEXIST-trick doesn't apply; we chown the
   already-existing tree instead. s6-supervise keeps using the
   same files; it never re-asserts ownership on a running service.
   The script skips s6-overlay internal services (s6rc-*,
   s6-linux-*) so the supervision tree itself stays root-only.
   015- slot is intentional: lex-sorts between 01-hermes-setup
   and 02-reconcile-profiles in the container's C-locale, so
   the chown finishes before the reconciler walks the scandir.

Unregister teardown reordering
------------------------------
S6ServiceManager.unregister_profile_gateway now fires
s6-svscanctl -an BEFORE rmtree (with a 200ms grace), so
s6-svscan reaps the supervise child and releases its file
handles on supervise/lock + supervise/status before we try to
remove the directory. Previously rmtree raced s6-supervise on a
set of files inside the supervise dir, and even with the parent
supervise/ now hermes-owned, the contained files (death_tally,
lock, status, written by root) could still be in use.

Dashboard down-state redesign
-----------------------------
The original PR #30136 review fix wrote a 'down' marker file
into /run/service/dashboard/ via cont-init.d/03-dashboard-toggle.
That approach was broken in two ways:

  (a) /run/service/dashboard is a symlink to a TRANSIENT
      /run/s6-rc:s6-rc-init:<tmpdir>/ directory while s6-rc is
      mid-transaction; the touch landed in a soon-to-be-discarded
      tmp.

  (b) Even when written to the final /run/s6-rc/servicedirs/
      location, the 'down' file is only consulted by s6-supervise
      at slot startup. s6-rc's user-bundle explicitly transitions
      'dashboard' to 'up' on every boot, overriding any down
      marker.

The right fix is the canonical s6 pattern: when HERMES_DASHBOARD
is unset, the dashboard run script exits 0 and a companion
finish script exits 125. Per s6-supervise(8), exit code 125 from
the finish script is the 'permanent failure, do not restart'
marker — equivalent to s6-svc -O. The slot reports as 'down' to
s6-svstat, matching the reality that no dashboard process is
running. When HERMES_DASHBOARD IS truthy, finish exits 0 and
restart-on-crash semantics apply.

03-dashboard-toggle is removed (its function is now subsumed by
the run/finish pair).

Tests
-----
Adds four unit tests for _seed_supervise_skeleton covering the
produced layout, the log/ subservice case, the skip-when-no-log
case, and idempotency. The live-container verification continues
to live in tests/docker/test_s6_profile_gateway_integration.py and
tests/docker/test_dashboard.py — both now pass against the
rebuilt image.

References
----------
* Skarnet skaware mailing list 2020-02-02 (Laurent Bercot
  + Guillermo Diaz Hartusch) on unprivileged s6 tool semantics:
  http://skarnet.org/lists/skaware/1424.html
* just-containers/s6-overlay#130 — same EEXIST-preseed pattern,
  community-validated 2016 onward
* https://skarnet.org/software/s6/servicedir.html — exit-code 125
  semantics in finish scripts

(cherry picked from commit c41f908ad4)
2026-05-25 12:23:23 +10:00
Ben
1dfabe47b3
fix(docker): dashboard slot stays 'down' when HERMES_DASHBOARD unset
PR #30136 review caught a false positive: when HERMES_DASHBOARD was
unset, the dashboard run script did `exec sleep infinity`, so
`s6-svstat /run/service/dashboard` reported the slot as 'up'.
`hermes doctor` and any other s6-svstat-based health check saw the
dashboard as supervised-running even though no dashboard process
existed.

Add cont-init.d/03-dashboard-toggle: writes a `down` marker file
into `/run/service/dashboard/` when HERMES_DASHBOARD is falsy,
removes any leftover marker when it's truthy. s6-supervise honors
`down` by not starting the service, so s6-svstat reports 'down' —
matching reality.

The run script's HERMES_DASHBOARD case-statement stays in place as
a belt-and-suspenders guard, so the two layers can never disagree.

Two new integration tests lock the behavior: slot reports down
when unset; slot reports up when set to 1.
2026-05-24 18:05:33 -07:00
Ben
fc39296e1f
fix(service_manager): s6 detection works for unprivileged hermes user
PR #30136 review surfaced two issues, both rooted in the same audit gap:
docker integration tests were running as root, not the unprivileged
`hermes` user (UID 10000) that the runtime actually uses via
`s6-setuidgid hermes`. Anything that probed PID-1 state or wrote to
the s6 control surface worked as root in the tests but was inert in
production.

Fixes:

1. `_s6_running()` previously called `Path("/proc/1/exe").resolve()`,
   which is root-only readable. For UID 10000 the symlink yields
   PermissionError, `resolve()` silently returns the unresolved path,
   and `exe.name == "exe"` — so detection always returned False, the
   service-manager runtime-registration path was inert, and every
   `hermes profile create` / `hermes -p X gateway start` silently
   skipped the s6 hook. Replace with `/proc/1/comm` (world-readable)
   + `/run/s6/basedir` (s6-overlay-specific) — both required, fail
   closed.

2. `02-reconcile-profiles` now also chowns `/run/service/.s6-svscan/`
   {control,lock} to hermes so `s6-svscanctl -a/-an` works without
   root. Previously the directory chown stopped at `/run/service`
   and the FIFO inside stayed root-owned, so `register_profile_gateway`
   from hermes failed at the rescan-trigger step with EACCES — the
   wrapper in profiles.py caught the exception and printed a swallowed
   warning, so profile creation appeared to succeed while the slot
   was rolled back.

Audit changes to flush this class of bug next time:

- Add `docker_exec` / `docker_exec_sh` helpers to `tests/docker/conftest.py`
  that default to `-u hermes`. The module docstring explains why and
  flags `user="root"` as opt-in only for tests that explicitly need
  root (none currently do).
- Refactor every `docker exec` call in tests/docker/ through the new
  helpers (test_dashboard.py, test_zombie_reaping.py, test_profile_gateway.py,
  test_container_restart.py, test_s6_profile_gateway_integration.py).
- Add 5 unit tests covering `_s6_running` under various probe states
  (both signals present; comm wrong; basedir missing; PermissionError
  on /proc/1/comm; missing /proc — non-Linux). The PermissionError
  test is the explicit regression guard for the original bug.

Known follow-up: the per-service `supervise/control` FIFO inside each
`/run/service/gateway-<profile>/supervise/` is created root-owned by
s6-supervise (which runs as root because s6-svscan is PID 1). `s6-svc
-u/-d/-t` from the hermes user will get EACCES on those. The audit
under `-u hermes` will reveal this in lifecycle tests — surfacing the
issue cleanly so it can be fixed in a focused follow-up (likely via a
small SUID helper or a polling chown loop in cont-init.d). The
detection + svscanctl fixes here are independent and complete on
their own.
2026-05-24 18:05:33 -07:00
Ben
2afefc501c
feat(docker): per-profile s6 supervision + container-restart reconciliation
Phase 4 of the s6-overlay supervision plan. Activates the Phase 3
S6ServiceManager by hooking it into the profile lifecycle and the
`hermes gateway start/stop/restart` dispatcher, and adds a cont-
init.d-time reconciliation pass that survives `docker restart`.

Task 4.0 — container-boot reconciliation:
  /run/service/ is tmpfs, so every `docker restart` wipes every
  per-profile gateway slot. /etc/cont-init.d/02-reconcile-profiles
  invokes hermes_cli.container_boot.reconcile_profile_gateways() on
  every boot, which walks $HERMES_HOME/profiles/<name>/, reads each
  gateway_state.json, recreates the s6 service slot, and auto-starts
  only those whose last state was 'running'. Other states
  (stopped, starting, startup_failed, missing) register the slot
  in the down state — avoiding crash-loops across restarts for a
  gateway that was broken last boot. Per-profile outcome is recorded
  to $HERMES_HOME/logs/container-boot.log.

  Implementation: hermes_cli/container_boot.py + 12 unit tests.
  Profile-marker is SOUL.md, not config.yaml, because `hermes profile
  create` only seeds SOUL.md by default (config.yaml comes from
  `hermes setup`).

Task 4.1 / 4.2 — profile create/delete hooks:
  hermes_cli/profiles.py::create_profile now calls
  _maybe_register_gateway_service(<canon>) at the end, which routes
  through ServiceManager.register_profile_gateway when running on s6
  and no-ops on host backends. delete_profile mirrors with
  _maybe_unregister_gateway_service. _allocate_gateway_port produces
  a deterministic SHA-256-derived port in [9200, 9800).

Task 4.3 — gateway dispatch + remove rejection arms:
  _dispatch_via_service_manager_if_s6(action) intercepts
  start/stop/restart at the top of each subcommand and routes them
  through S6ServiceManager.{start,stop,restart}. The pre-Phase-4
  `elif is_container():` rejection arms are kept as fallback for
  pre-s6 containers / unsupported runtimes, but only ever fire when
  detect_service_manager() != 's6'. install/uninstall under s6
  print informational guidance pointing users at profile create/delete.

  Removed the two xfail(strict=True) markers from
  tests/docker/test_profile_gateway.py — both tests now pass strictly.

Task 4.4 — status reporting:
  get_gateway_runtime_snapshot() reports
  Manager: 's6 (container supervisor)' inside an s6 container instead
  of 'docker (foreground)'.

Plan-vs-reality drift fixed in this commit:
  - Plan's S6ServiceManager._render_run_script used
    `gateway start --foreground --port {port}` — invented args; the
    real CLI is `gateway run`. Switched accordingly. port arg
    retained for API parity but now documented as 'currently ignored'.
  - Plan's reconciler keyed on config.yaml; switched to SOUL.md
    (config.yaml is created by hermes setup, not by hermes profile
    create, so the original gate caught nothing).
  - The plan's _dispatch helper used _profile_arg() which returns
    '--profile <name>' (i.e. with the flag prefix). Switched to
    _profile_suffix() which returns the bare name.
  - Architecture B's docker exec doesn't get /command on PATH or
    the venv on PATH; Dockerfile's runtime PATH now includes
    /opt/hermes/.venv/bin so 'docker exec <c> hermes ...' works
    without sourcing the venv.
  - stage2-hook now chowns $HERMES_HOME/profiles to hermes on every
    boot, not just on the UID-remap path. Without this, files created
    by docker-exec-as-root accumulate and the next reconciler run
    fails with PermissionError reading SOUL.md.

Test harness:
  19 passed, 0 xfailed (the two pre-Phase-4 xfail targets flip to
  passing). 78 unit tests across service_manager + container_boot +
  profiles_s6_hooks + gateway_s6_dispatch. Hadolint + shellcheck
  pass cleanly.

Refs: docs/plans/2026-05-07-s6-overlay-dynamic-subagent-gateways.md
2026-05-24 18:05:33 -07:00