Re: FUSE merging?

From: Miklos Szeredi
Date: Fri Jul 01 2005 - 01:37:49 EST


> However, a few things:
>
> - is there anything in the current implementation of the permission stuff
> which might tie our hands if it is later reimplemented? IOW: does the
> current FUSE user interface in any way lock us into the current FUSE
> implementation (fuse_allow_task())?

No. This thing is above the userspace interface and completely
independent. Either a task is allowed, and then the request goes
through to the interface. Or if it's not, the request is stopped
right there, and never reaches the userspace interface.

> - the fuse mount options don't seem to be documented

True. I'll send a patch (they are documented in the README of the
fuse distribution).

> - aren't we going to remove the nfs semi-server feature?

I leave the decision to you ;) It's a separate independent patch
already (fuse-nfs-export.patch).

> - Frank points out that a user can send a sigstop to his own setuid(0)
> task and he intimates that this could cause DoS problems with FUSE. More
> details needed please?

Will follow up in Franks answer.

> - I don't recall seeing an exhaustive investigation of how an
> unprivileged user could use a FUSE mount to implement DoS attacks against
> other users or against root.

Here's a description of a theoretical DoS scenario:

http://marc.theaimsgroup.com/?l=linux-fsdevel&m=111522019516694&w=2

Miklos

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/