# Test campaign #3 — "NO MERCY" brutal chaos/edge — 2026-06-22 (demo 9201)

> **Status: empirical findings from an unattended brutal chaos campaign (2026-06-22).** Push the
> system into unintended states; verify it handles-or-fails-safe, then recovers. Every break carried a
> timed auto-revert; the Phase-0 verified PBS backup was the floor. ctrl **v0.75.0** + agent v0.39.0.
> Demo restored to baseline (25 containers, 0 unhealthy) and healthy at the end. Per-check raw evidence:
> `felhom-controller/TEST-REPORT.md`. **No silent-corruption and no path-escape/exfil found** (the two
> highest-severity classes). **No code changes shipped** — findings are behaviours logged for supervised fix.

## Result matrix
| Phase | Result |
|---|---|
| 0 baseline + verified PBS backup floor | PASS (gate open) |
| 1 resource starvation (R1 RAM 91%, R2 settings-atomicity, R3 rootfs 94%, R4 mem-gate) | PASS (fail-safe held) |
| 2 state corruption (S1 settings, S2 app.yaml, S3 quiesce marker, S4 symlink) | PASS + 1 medium (S1) |
| 3 concurrency (C1 4-way ops, C2 drive-flap×5, C3 kill-agent-mid-backup) | PASS |
| 4 time chaos (clock jumps) | SKIP (architectural — see below) |
| 5 network partitions (N1 tunnel block, N2 PBS block mid-backup) | PASS |
| 6 security fuzzing (F1 JSON, F2 traversal, F3 hostile compose, F4 weird filenames) | PASS (no escape) + 1 medium (F2) |
| 7 brutal recovery (B1 dockerd restart, B2 kill-9 ctrl, B3 reboot+flash-detached, B4 host reboot) | PASS (B1-B3); B4 SKIP |

## Findings, ranked by real-world severity

### 1. [MEDIUM] Corrupt `settings.json` → controller FATAL crash-loop (Phase 2 / S1)
A truncated/invalid `settings.json` makes the controller `[FATAL] Failed to load settings … unexpected
end of JSON input` and **crash-loop** (RestartCount climbs via docker's restart-manager) — **no
safe-defaults fallback**; the management plane is down until the file is fixed. It is *not silent*
(FATAL is logged). Apps + tunnel keep running (control/data separation). **Contrast:** per-stack
`app.yaml` corruption (S2) is handled gracefully — controller logs `[WARN] LoadAppConfig: yaml: …`,
marks that app, keeps serving others, no crash. **Recommend:** make the settings.json load path match
app.yaml's — log a WARN + load safe defaults (or boot read-only), not `[FATAL]`.

### 2. [MEDIUM, defense-in-depth] Restore `stack_name` not validated against path traversal (Phase 6 / F2)
`POST /backup/restore` proceeds with a traversal `stack_name` (`../../../etc`) into
`RestoreFromRecoveryUnit`/`RestoreApp` (`GetAppDrivePath` returns the default `/mnt/sys_drive`).
**No escape occurred** — `/etc/passwd` intact, no `/opt/etc`/`/etc/passwd/` artifacts, no `/etc` writes
— **only because** downstream `StopStack`/`StartStack` are map-based (`stack "../../../etc" not found`)
and there's no recovery-unit/volumes for a bogus name (no-op). The security boundary held, but by
luck of downstream behaviour, not by input validation. A future code path that built a filesystem path
from the raw name could escape. **Recommend:** explicit `stack_name` validation at the restore handler
(reject `/`, `..`, NUL). (Storage `where=` IS validated — `gateWhere`: `path.Clean`+`HasPrefix("/mnt/")`
rejected all 5 traversals.)

### 3. [LOW] Corrupt quiesce marker silently ignored (Phase 2 / S3)
A bad-JSON `quiesce-state.json` does **not** panic the controller at startup (good — stacks not
stranded), but the unparseable marker is **neither logged nor cleared/quarantined**. A real
corrupted-mid-quiesce marker would silently skip stack-recovery. **Recommend:** log + quarantine a
marker that fails to parse.

### 4. [INFO] Boot-ordering, re-confirmed (Phase 7 / B3)
On a guest reboot with a drive detached, docker's boot-restore attempts drive-backed bind-source
`mkdir` before mounts converge — but the **unprivileged-LXC mapping denies it** (2 denied attempts,
**no rootfs shadow dirs**), and the v0.75 mountpoint-gate covers the controller's belt/FileBrowser.
Benign but noisy. (Tracked from the v0.75 task.)

## What held (highlights)
- **No path-escape / no /etc exfil** anywhere: storage `where=` validation (F2), symlink-in-backup not
  followed (S4 — rsync preserved `EVIL_ETC -> /etc`, no contents copied), restore-traversal no-op (F2).
- **Resource pressure** (R1 91% RAM, R3 94% rootfs): controller + 25 apps stayed healthy, no OOM, no
  daemon restart, **settings.json stayed valid** (atomic tmp+rename, R2).
- **Concurrency**: single-flight serialized 4-way op storm (C1), drive flap×5 converged with the v0.75
  gate firing 5 clean skips and **0 permission-denied** (C2), agent-kill-mid-backup unwound the quiesce
  with no stack stranded (C3).
- **Partitions**: tunnel block → apps serve locally + reconnect (N1); PBS block mid-backup → backup
  fails safe + quiesce unwinds + next backup succeeds (N2).
- **Recovery**: dockerd restart → all back <8s (B1); `kill -9` controller → `unless-stopped`
  auto-recovers in 8s (B2, re-confirms Finding #1); reboot+flash-detached → apps held, **no shadow
  dirs**, reconnect recovers (B3).

## Phase 4 SKIP — time chaos not safely isolable (architectural)
The guest is an **unprivileged LXC**: it cannot set its own clock (`date -s` → `Operation not
permitted`) and shares the host's `CLOCK_REALTIME` (time namespaces don't isolate the wall clock). The
only way to jump the guest wall-clock is to change the **host** clock, which would risk the cloudflared
tunnel cert, the agent leaf-cert pin, and **agent→DooPlex hub/PBS TLS auth** (§0.1 forbids degrading
DooPlex). Proper venue: a dedicated throwaway VM with its own clock, or an injectable-clock unit test.

## Deferred / supervised / implementation
- **Fix S1** (settings.json: safe-defaults + WARN instead of FATAL crash-loop) — highest priority.
- **Fix F2** (explicit restore `stack_name` traversal validation).
- **Fix S3** (log + quarantine a corrupt quiesce marker).
- **Time chaos** (Phase 4) on a dedicated VM / injectable clock.
- **Host reboot** (B4) — supervised (no physical recovery unattended).
- `.fab` import compose-fuzzing (F3) — the only customer compose vector; not exercised.

## Cleanup
9201 running, 25 containers, 0 unhealthy; controller + cloudflared healthy; agent active; both drives
mounted; rootfs 4%/29 G free. No leftover iptables rules (host 8007, guest DOCKER-USER both 0); all
campaign timed-guards killed; corrupted files restored (settings valid, app.yaml restored, quiesce
marker removed, symlinks removed); F4 test files removed; no 9300/scratch/loopback created. Demo =
Phase-0 baseline.
