smbmount and ownership of dir for mounting

[Urban Widmark]

On Mon, 17 Dec 2001, Brenton Judge wrote:

> Why can a user only mount on a directory which he owns with smbmount?
> Surely write permission should be enough worst case and likely this too
> should not be required.  Other mount code allow mounts to occur without

Paranoia. 'smbmount //evil_server/evil_share /tmp' and now I own all the
tempfiles created. Are you certain that no program ever creates sensitive
data on /tmp?

And if I don't need write permission, then how about
'smbmount //evil_server/evil_share /bin'
"Oh look, root started a shell. Now I have a shell too."

If you need to change this you can edit the mount_ok function in
source/client/smbmnt.c. It has a test at the end that checks if getuid
equals st_uid of the mountpoint.


> ownership (for example the CD-ROM mounting to /mnt/cdrom when ANY user types
> mount /mnt/cdrom without either ownership or write permission).  It seems
> inconsistent.  If the problem is in mounting over other people stuff then
> surely there should be an exception if it is listed is /etc/fstab

smbmount should not allow any user mounts except those that are listed in
/etc/fstab. It should work like any other fs.

It doesn't parse /etc/fstab itself and allow mounts based on that as some
people thought adding that dependency was a bad idea.

On a 2.5.something kernel, with an updated mount from a not-yet released
util-linux and with "smbconnect" from a future samba version smbfs will be
mounted just like any other fs. All the normal mount options will work,
user, noauto, noexec without complaints.

If you want to test this now you can, if you let me dig up the patches. I 
think I even wrote some instructions ...

/Urban