I am running Ubuntu 5.10, with a 2.6.12 kernel. When I connect a USB disk with a VFAT file system, it turns up as /media/My\ Book, with owner root.root and permissions rwx------ .

So far, so good, but I cannot chown or chmod this. These commands, run as root, simply do nothing. I have also tried to remount in various ways, to no avail. Typically the commands just return silently and nothing has changed.

I want to share this device with others, via Samba, so I should like to set something like rwxrwxrwx (we will discuss security later ;-) so where do I start?

I have also looked in /etc/udev.rules, but found nothing directly relevant.

Try looking through the man files for mount.
Try remounting it with mount -wo exec nosuid
(I think...)
Which will give it read/write acess with executable binaries allowed and ignoring user IDs.

If this doesn't help, feel free to ignore it.

Thanks, but, yes-- I also tried quite a few variations on mount. Including your suggestion. Unfortunately, nothing changes :-(

Uh yes, and I also found that remounting with various options does change at least something: when I give 'mount' the /dev/sda1 shows up with all "new" options appended. Currently it is something like user=root,....,uid=1001,... . The drive still works, and is still accessible, as long as you are root. And /media/My\ Book still has root.root drwx------ .

BTW, does anyone know exactly where a USB disk is mounted? I have been looking in the /etc/udev rules, but I do not see anything related to my problem. Should I try /etc/hotplug, or something else? Or is it in the kernel?

hi,
if not specified at run time ( boot up ) via /etc/fstab then plug and pray should take care of it:
>
cat /etc/mtab
should see something similar to:
>
cat /etc/mtab
/dev/hdb2 / ext3 rw 0 0
none /proc proc rw 0 0
none /dev/pts devpts rw,gid=5,mode=620 0 0
usbdevfs /proc/bus/usb usbdevfs rw 0 0
/dev/hdb1 /boot ext3 rw 0 0
none /dev/shm tmpfs rw 0 0
>
usbdevfs is the one
>
normally i do not create an /etc/fstab as i like to hot swap between machines.
So i just do following
fdisk -l
validate the drive is being seen then
mount /dev/sda1 /<mount point> eg usb1
>
hope that makes sense, cheers.

I could place a line specifying /dev/sda1 in /etc/fstab, of course, and I guess that would also set the permissions right. But unfortunately, sometimes it is /dev/sdb1 after it has been plugged in ... even though I have no other (SCSI or USB) devices on this machine.

That is why I am still looking for udev rules of some kind...

It's a dirty hack but you can put entries in fstab for sda1, sdb1, etc. with all needed permissions.