forked from unom/punktfunk
enricobuehlerandClaude Fable 5
47d22b6082
A retrying unpaired client parks one QUIC connection per knock, but the delegated-approval waiters were keyed on fingerprint alone — one console Approve resolved ALL of them. Observed live (2026-07-10): an iPad knocked 3x, one Approve admitted three full sessions, three Mutter virtual monitors were created within ~200us plus an ApplyMonitorsConfig, and gnome-shell SIGSEGV'd inside meta_monitor_manager_rebuild — dropping the box to the GDM greeter, unreachable until reboot (GDM auto-login runs once per boot) while the lingering host spammed "RemoteDesktop ... not activatable" libei errors. Four fixes, outermost symptom inward: - Knock generations (native_pairing): note_pending returns a per-knock generation; a re-knock bumps it and wakes the previous waiter, which resolves the new PairingDecision::Superseded (connection closes; the console list is unchanged). An approval records WHICH generation it admitted, so a stale waiter polling only after the pending entry is cleared still loses the tie — exactly one admission, no matter the interleaving. - TOPOLOGY_LOCK (vdisplay/mutter): every Mutter monitor mutation (pre-snapshot -> RecordVirtual -> ApplyMonitorsConfig, and the teardown Stop) is serialized process-wide. Concurrent rebuilds are what segfault the shell (second on-glass crash of this class — the teardown race is already documented in-file), and serialization also keeps wait_virtual_connector's snapshot diff from attributing a sibling's connector. Create timeout 20s -> 45s for lock queueing. - Session-env hygiene (vdisplay): when detection finds NOTHING live, clear the previous connect's XDG_CURRENT_DESKTOP/WAYLAND_DISPLAY retarget. A stale GNOME value kept mutter::is_available() true after the crash, routing explicit-backend connects into the dead session (create timeouts + libei error loops) instead of the crisp "no live graphical session" handshake error. - Opt-in recovery hook (config + punktfunk1): PUNKTFUNK_RECOVER_SESSION_CMD fires (detached via sh -c, debounced to one launch/min) when a client connects while no graphical session is live — e.g. `sudo -n systemctl restart gdm` re-runs auto-login and the client's retry lands in the recovered desktop. The handshake error tells the client to retry. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>