mount_smbfs/umount for non root user.
Malcolm Kay
malcolm.kay at internode.on.net
Fri Oct 27 15:51:11 UTC 2006
Running mount_smbfs as a regular user generates a permission
denial in relation to iconv in the kernel.
This is apparently a well known problem which can be circumvented
by setting the set-user-id-on-execution bit for mount_smbfs.
This works for me but leads to the problem that the mount is now
seen as belonging to root and the regular user gets a denial on
umount.
Allowing regular users to mount smb shares with mount_smbfs seems
to me fairly benign but to set the set-user-id-on-execution bit
for umount would be extremely dangerous.
Is there a way around this problem -- this is under FreeBSD 5.4.
Taking a look at the sources for mount_smbfs and the associated
library, libsmb, I see that conditional compilation for APPLE
(Darwin?) switches the effective user id when the
set-user-id-on-execution bit is set with the code executed
mostly under the identity of the real user and switching to
privileged mode only for a few brief activities - notably for
installing the iconv table and a few error conditions. Apart from
this the code looks very similar to (but not quite identical
with) the FreeBSD code.
I presume (without any real justification) that these differences
in the APPLE version are intended to circumvent the difficulty I
am having when running under Darwin.
The question is if I modify the FreeBSD code to perform similar
switchings of effective user id and recompile am I likely to
achieve my desired goal? Has anyone else tried this?
Any comments would be welcome.
Malcolm
More information about the freebsd-questions
mailing list