Re: SanDisk USB stick problem

[Celejar <celejar@gmail.com>]

On Wed, 9 Dec 2020 19:10:42 +0000
Joe <joe@jretrading.com> wrote:

> On Wed, 9 Dec 2020 13:35:57 -0500
> Celejar <celejar@gmail.com> wrote:
> 
> > On Tue, 8 Dec 2020 20:39:35 -0800
> > David Christensen <dpchrist@holgerdanske.com> wrote:
> > 
> > ...
> > 
> > > As you have not stated how you mounted the drive, I will assume
> > > that you plugged it in, an icon appeared on the desktop, you
> > > interacted with the icon, and the drive was mounted at /media/usb0.
> > >  If so, AIUI the various Debian desktops with automounting use
> > > FUSE.  The user account running   
> > 
> > They do? Do you have documentation of this? I can't find anything
> > about this in the documentation of, say, Xfce4's thunar-volman:
> > 
> > https://docs.xfce.org/xfce/thunar/using-removable-media
> > 
> > > the desktop and automounter will have whatever access controls that
> > > are supported by the filesystem and/or by FUSE.  But all other user 
> > > accounts, including the root account (!), are denied access to the 
> > > filesystem.  This is a security feature of FUSE.  See
> > > mount.fuse(8).  
> > 
> 
> I haven't investigated it thoroughly, but when I have casually checked
> what is mounted, I see that any USB sticks plugged in are on fuse. Xfce
> on sid, no usbmount, automounting done by systemd, by the way.

Interesting. I haven't been using automounting, but I just enabled
Xfce's native automounting (Thunar / Edit / Preferences / Advanced /
Volume Management:Configure / Mount removable drives when hot-plugged)
and stuck in a flash drive. It gets mounted and I don't see any FUSE
involved:

~$ mount | grep sdb
/dev/sdb on /media/<username>/disk type vfat (rw,nosuid,nodev,relatime,uid=1000,gid=1000,fmask=0022,dmask=0022,codepage=437,iocharset=ascii,shortname=mixed,showexec,utf8,flush,errors=remount-ro,uhelper=udisks2)

~$ mount | grep fuse
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
portal on /run/user/1000/doc type fuse.portal (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)

I'm curious about this because I can't imagine that FUSE performance is
as good as native, so why would automounters pay the performance
penalty of FUSE when native mounting would seem easy enough to do?

Celejar