sandboxed - Failed to open frecency/history database

[black-snow]

I have the fff pi plugin installed in my nono-sandboxed pi. At startup it errors with

Error: (fff): Failed to open frecency/history database (Failed to init frecency db: Failed to open frecency database env: Operation not permitted (os error 1)). Continuing without frecency persistence.

and I don't quite see why. It does not complain when not sandboxed. I have r/w allowed on ~/.pi/agent/fff/, which does in fact contain the DB and lock. I can stat and read the DB in there just fine from a sandboxed process, so I assume it's actually something else that fails but I can't tell what it is.

Any ideas? Nono also doesn't show any rejected reads or writes.

[dgesteves]

If you're on macOS, it isn't the files, it's LMDB's lock. fff keeps frecency/history in LMDB through heed 0.22 (Cargo.toml) without heed's posix-sem feature, and on macOS LMDB then locks with SysV semaphores: ftok() on lock.mdb, then semget()/semctl() (mdb.c, here). nono's Seatbelt profile starts from (deny default) and never allows ipc-sysv-sem; even ipc_mode: "full" only adds ipc-posix-sem* (macos.rs, v0.80.0). So semget gets EPERM, heed reports Operation not permitted (os error 1), and nono logs nothing because no file read or write was refused.

Fix: allow SysV semaphores in a profile you own. nono only applies raw Seatbelt rules from user profiles (it strips them from pack and built-in ones), so add this to the profile you run pi with, or wrap the pack in ~/.config/nono/profiles/pi-local.json:

{
  "extends": "nolabs-ai/pi",
  "meta": { "name": "pi-local", "version": "1.0.0" },
  "unsafe_macos_seatbelt_rules": ["(allow ipc-sysv-sem)"]
}

and start it with nono run --profile pi-local -- pi.

I checked this with a small C program built from the same LMDB source fff ships (lmdb-master-sys 0.2.5) that opens an env with MDB_NOTLS, under sandbox-exec on macOS: with (deny default) plus file/process/mach access it fails with Operation not permitted, adding (allow ipc-posix-sem*) still fails, and adding (allow ipc-sysv-sem) opens the env and commits a write. I didn't run nono itself. On Linux LMDB uses robust mutexes inside lock.mdb instead, so if you're on Linux this isn't your cause.

[black-snow]

Thanks for the thorough explanation. That does seem to fix it - at least the warning went away.

[dgesteves]

Glad it helped, and thanks for confirming the warning is gone.