Can't disable unused filesystems

Posted Feb 23, 2013 12:39 UTC (Sat) by cortana (subscriber, #24596)
In reply to: Can't disable unused filesystems by jmorris42
Parent article: A story of three kernel vulnerabilities

It might be possible to implement something like this today with udev rules... if you could set the UDISKS_SYSTEM_INTERNAL property on a disk based on the value of one of its partitions ID_FS_TYPE properties. However I don't know how well that would interact with more interesting disk layouts (e.g., NTFS filesystem inside a LUKS container only unlocked once the user has double-clicked on it in the GUI).

As for /etc/filesystems and /proc/filesystems, these days mount itself only seems to consult them if '-t auto' is used (or '-t' is absent entirely) and if libblkid fails to identify the correct filesystem. So I get the feeling that /etc/filesystems is really a remnant of an obsolete feature that hasn't been used since kernel module autoloading went in.

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Can't disable unused filesystems

Posted Mar 2, 2013 16:59 UTC (Sat) by jmorris42 (guest, #2203) [Link] (2 responses)

Yea, /etc/filesystems is documented as only being consulted for -t auto or leaving the switch off entirely. If you explicitly specify a filesystem you expect the system to do what you told it.

But the key point remains, after several replies nobody can point to a way to actually solve a problem that exists on all graphical desktops.

udev is clearly not intended to be modified by the end user. It isn't documented, the files controlling it are written in a way to be hostile to manual editing and the entire subsystem has been churning for years.

Simply stopping the modules from loading isn't a good solution either.

You can't even reliably suppress the icons from appearing on a desktop. I once found a way to do it, it worked until the next Fedora.

Can't disable unused filesystems

Posted Mar 3, 2013 15:42 UTC (Sun) by cortana (subscriber, #24596) [Link] (1 responses)

udisks does provide properties you can use to prevent volumes from being mounted by and/or shown to the user, so this should be possible. The churn is a huge pain in the arse, however. And I see it's about to get worse, since udisks is being replaced by udisks2... :/

Can't disable unused filesystems

Posted Mar 4, 2013 15:27 UTC (Mon) by nix (subscriber, #2304) [Link]

In effect udisks has been unmaintained for ages. I've reported several bugs that could well be security holes upstream (writes through null pointers, writes through uninitalized, pointers, the code quality is really quite dire). Not one has ever got a response.