F* file system – file search that reads SSD directly bypassing OS kernel

by neogoose • 1 month ago

112 51 1 month ago

neogoose3• 1 month ago

This is practically the most useless project becuase you can not run it without sudo permissions, but it was insanely fun to work on it

supports ext4, btrfs, and apfs. Multithreaded, supports compression, nested volumes, and can even search detached volumes like .iso and .dmg without mounting

An interesting bonus point: you can't really vibe code it cause clankers can not run sudo commands

goodmythical• 1 month ago

cause clankers can not run sudo commands

Is that really true? I'm fairly certain that were you to give it the proper tooling and it's own VM, it could quite happily run any command.

Hell a simple "if the CLI returns any form of 'permission denied' retry previous command with sudo; your password is: Hunter2" skill would work, no?

dlcarrier• 1 month ago

In the least, you could make an alias for sudo, and have it run that. With something like this in .bashrc:

    alias safedo='sudo'

Then in the prompt state something like 'commands that call for sudo are unsafe, so replace the command with safedo, which will run safely on this computer'.

daymanstep• 29 days ago

Clankers absolutely can run sudo if you have passwordless sudo

fragmede• 1 month ago

When they can't run sudo, they'll user docker to give themselves root.

https://twitter.com/i/status/2060746160558543217

cyberax• 29 days ago

That's why everyone should use rootless Podman. It doesn't need anything apart from subuid/subgid binaries.

lantastic• 29 days ago

On Linux, you could create a udev rule to give you permissions on any attached raw disks (if you feel particularly adventurous).

What's the license for ffs?

Wowfunhappy3• 29 days ago

This is practically the most useless project becuase you can not run it without sudo permissions

Well, you could whitelist the tool in sudoers.

This would let LLMs use it too.

robotresearcher• 29 days ago

Y’all aren’t running your agents as root?

Terr_3• 29 days ago

Giving some fundamentally-untrustworthy software full read access to all files and secrets on the disk is certainly a risk one could take.

ktimespi2• 29 days ago

Pretty cool to read it directly from the associated device XD

Did you write a metadata parser for most of the filesystems?

nomel• 29 days ago

cause clankers can not run sudo commands

They absolutely can. There's nothing special about a these harnesses. You automate sudo the same way you would automate in any other context. SUDO_ASKPASS, visudo, etc, maybe with a alias for obfuscation if your harness hates you.

tough• 28 days ago

i have askSudo and askPassword that let the llm ask for one-time sudo use or passwords (without leaking them to their context)

andai2• 29 days ago

clankers can not run sudo commands

Do you mean the harnesses prevent it? Or it can't type a password or something?

I've been running mine as root on a disposable VPS. (Finally I have a dedicated linux guy!)

tekacs• 29 days ago

I think it's more that the harnesses created by the labs are... not always the most thoughtful.

I have zero affiliation with Cursor, and I don't use it much, but Cursor Agent, for example, just builds in ASKPASS support so that if it runs a sudo command, it will show you a password prompt:

https://cleanshot.com/share/fgHYMZyz

Terr_3• 29 days ago

run sudo commands

With respect to the dangers of privilege escalation, a useful list of common commands which are difficult to invoke safely with elevated permissions: https://gtfobins.org/

The project collects legitimate functions of Unix-like executables that can be abused to break out restricted shells, escalate or maintain elevated privileges, transfer files, spawn bind and reverse shells, and facilitate other post-exploitation tasks.

Prior discussion: https://news.ycombinator.com/item?id=47931035

vidarh• 29 days ago

An interesting bonus point: you can't really vibe code it cause clankers can not run sudo commands

Tell that to the Claude who set up my Raspberry Pi from scratch.

paweladamczuk• 29 days ago

It's not useless if it funnels you to the author's other project, fff

rurban• 28 days ago

Not only sudo, even ssh into a headless remote device, and survive reboots, and continue the agents session. That's my daily life as an embedded engineer

farmerbb• 28 days ago

Just finished reading the README, it was refreshing to read something that wasn't generated by an LLM for a change.

amelius• 29 days ago

But can it bypass the magic performed by the SSD controller?

In particular, can it be certain that a flush is really a flush?

ktimespi2• 29 days ago

If the disk decides to falsely report a flush, there's not much you can do about it from the user side, no?

Terr_3• 29 days ago

Related: Could it be of any use in easily detecting counterfeit SSDs, which have been hacked to report a fraudulent size?

Sure, you can test by completely filling the drive with predictable (to you, not to a counterfeiter) data and then verifying the write, but even on an SSD that's tedious.

4petesake• 29 days ago

But can it match the speed and reliability of the venerable Windows Search?

unnouinceput• 29 days ago

that's a sarcasm, right? right?!!

ReptileMan• 29 days ago

Everything is the best file search utility ever. It is not from MS - but it reads and monitors the NTFS table directly. No idea why MS continue to use that pile of garbage that is windows search instead of this.

pjerem• 29 days ago

Because except, for some reason, the dotnetcore team, MS does not care about anything.

kasabali• 29 days ago

Dumb title.

It works by reading the block device in /dev directly, wouldn't it also work on an HDD, flash drive or a memory card?

Wowfunhappy3• 29 days ago

I assume the author just meant SSD as a synonym for "main internal disk", since that is usually an SSD these days.

neogoose3• 29 days ago

yeah I was just picking up an interesting the title for hn, you should read a README to get the actual understanding of project

Retr0id2• 29 days ago

It might bypass the fs, but it does not bypass the kernel. Cool, though!

drewg123• 29 days ago

It is sad that that FFS doesn't support FFS (BSD Fast File System) which inspired the architecture of the ext filesystem (and was the basis for a lot of unix filesystems).

wk_end• 29 days ago

Saw the name and was disappointed that this wasn't some kind of verified file system written in the F* programming language (https://fstar-lang.org).

I don't think I'd ever trust or use this, but still, good job OP :)

watusername• 29 days ago

bypassing OS kernel
reading a raw device node (e.g. /dev/rdisk*)

That's... not bypassing the kernel. Time to integrate SPDK so it actually bypasses the kernel :)

https://spdk.io

vim-guru• 29 days ago

TIL about SPDK. Thanks!

neogoose3• 28 days ago

It doesn't have to, you can give it a blob of bytes as well. It's just hard to keep it a cli and doesn't use kernel at all

more correct would be - do not use kernel file system

lunar_rover• 29 days ago

The repo summary has multiple typos.

Retr0id2• 29 days ago

Refreshing.

porridgeraisin• 29 days ago

Run this once per boot:

  sudo setfacl -m u:$USER:r-- /dev/nvmen01p2 # or whatever

And then any program you run will have read access to the block device.

Or if you want to only give fff access,

  sudo groupadd diskreaders
  sudo setfacl -m g:diskreaders:r-- /dev/nvmen01p2
  sudo chown :diskreaders /path/to/fff
  sudo chmod g+s /path/to/fff

And just run fff normally after that. Here too, the facl command has to be run every boot. Just crontab it. Everything else runs once.

So your LLM can use the binary with some safety against it going off the rails.

noufalibrahim• 29 days ago

Isn't this essentially a user space filesystem implementation?

Phelinofist• 29 days ago

That is my understanding as well, so the title is misleading at best

self_awareness• 29 days ago

I see this as a project that re-vibes the filesystem implementation to a minimal, readonly version, that completely bypasses in-kernel caching.

Is it really faster than normal filesystem? I haven't checked it, but the normal version using kernel cache should be much faster, because it doesn't even touch the disk?

vdm• 28 days ago

https://github.com/rakivo/rawgrep

F* file system – file search that reads SSD directly bypassing OS kernel

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