The jail recorded each case's exit code but reported only timeouts,
discarding every other non-zero status. A suite with a failing assertion
exited 0 through the push gate -- the same blind spot that let an earlier
session ship 2 failing assertions in the nc_php suite. Found by negative
control, not by reading: a deliberately failing assertion still exited 0.
Propagating that status unconditionally was wrong, and caught before landing:
the jail's own usage example passes a `bogus` case that exits non-zero to
cover an error path, so a clean 5/5 = 100.00% run started failing. That is
the mode the 105-lib campaign runs in.
So the behaviour sits behind --fail-on-case-error, default off, passed only
by ci_mirror.sh and shell-tests.yml. Verified in all four quadrants:
measurement + error case = 0, gate + error case = 1, gate + clean suite = 0,
gate + broken assertion = 1.
Both gates also pass --min 0: with no --measure the jail was measuring
run_all.sh itself against its default --min 100 and failing the push at
54.55%, a coverage verdict neither gate asked for. ci_mirror.sh now prints
the jail's output on failure, so a red gate can be diagnosed.
The added flag pushed the jail over the 250-line cap, so the in-namespace
case runner moved to lib/shell_coverage_case_runner.sh, following the
existing lib/shell_coverage_jail_setup.sh split. All four quadrants were
re-run after the extraction.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016sxxsDHWgdRhmdmzNMA6XM
Investigated whether this session caused the 11:33 hard freeze. It did
not, and the evidence is recorded in the evidence artifact:
- No OOM kill, no oom_reaper, no hung-task or soft-lockup message, and
no kernel message AT ALL after 11:20. The log stops mid-line at
11:33:15 -- a hard hang, not a process the kernel was fighting.
- Last commit 11:30:32; last jail trace 11:11:57, 21 minutes earlier.
The session was idle when the machine died.
- Steam wrote a crash minidump at 11:31:10 and at-spi2 disabled an
unresponsive app at 11:32:06, on an RTX 3090. Correlation only -- a
hard hang leaves no log to prove cause.
- Nothing survived the reboot: no stray unshare/kcov, no leftover
tmpdirs, no leaked mounts, and the live /etc and /usr/local/bin
files keep their original dates.
Hardened anyway, because the jail had one genuinely unbounded
behaviour: a case could run forever. Two hangs yesterday came from a
`crontab -` fallback inheriting the caller's stdin.
Each case now runs under `timeout --kill-after=10s` (default 120s,
--timeout to override) with stdin from /dev/null, and a timed-out case
WARNS by name instead of being swallowed -- a silent timeout looks
identical to an unreachable line in the report. Verified: a `sleep 600`
subject now ends in 5s with --timeout 5s.
dot_resolver_install.sh still measures 39/39 = 100.00%.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DbD4nco3EgL1UFoZKmKsLE
nc_php.sh was the next-hardest library on the allowlist. It targets a
Debian Raspberry Pi -- it edits /etc/php/<ver>/apache2/php.ini, drives
occ as www-data and installs a crontab -- so none of its write targets
exist on this Arch host and the jail had nothing to mirror.
- --seed-dir / --seed-file create the paths a foreign-platform subject
expects. Verified with a probe: /etc/php/8.2/apache2 exists inside
the jail while /etc/php does not exist outside it.
- A failed bind is now FATAL, and missing mountpoints are created
first. A bind that fails silently is indistinguishable from
unreachable code in the report, which is the misdiagnosis this
runner exists to prevent.
- Mirroring skips unreadable targets (/root as a normal user) rather
than aborting under set -e.
nc_php.sh: 84/85 = 98.82%, 24 assertions. It STAYS on the allowlist,
because 98.82% is below the bar. Line 111 -- the crontab first-run
fallback -- hung the suite on both attempts to cover it, so it is left
uncovered and documented rather than tried a third time.
Two harness hazards found the hard way and written down: a top-level
stub function shadows the subject's own function for every later
assertion (this silently dropped coverage 83.53% -> 57.65% while the
tests still passed), and a stub for a piped-into command must drain
stdin or the writer takes SIGPIPE.
dot_resolver_install.sh still measures 39/39 = 100.00%.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DbD4nco3EgL1UFoZKmKsLE
The gate was a presence check -- 'a run_all.sh exists beside this lib' --
which an empty suite that asserts nothing satisfies. It now measures.
100% is reachable with no suppressions and no production source changes:
run the suite inside a user+mount namespace and the sudo-writes, systemd
units and nftables rules execute for real against a throwaway /etc.
- meta/scripts/shell_coverage_jail.sh: the runner, promoted out of a
session scratchpad. Two fixes it needed on the way: bind targets mirror
the real directory tree (an empty bind makes writes fail with ENOENT,
which reads as unreachable code), and sudo gets a pass-through stub
because real sudo cannot setresuid inside a userns.
- It fingerprints git status before and after and fails the run if a
write escapes the jail. Verified with a deliberate escapee.
- dot_resolver_install.sh: 39/39 = 100.00%, 28 assertions. Picked by
scoring every allowlisted lib on root ops, system writes and
destructive calls -- it scored highest in the repo. Allowlist 106 -> 105.
- jscpd was already over its own threshold at 2.45% and would have
rejected every commit staging a .sh file. Excluding vendored .venv/
shell alone gives 1.67%; also excluding lib/tests/ gives 1.47%.
The gate is deliberately NOT wired into the hook chain yet.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DbD4nco3EgL1UFoZKmKsLE
