Re: why does perl-suid not mount

[JavaFan]

There might be a check somewhere not only for the EUID, but also for the UID. Try setting $< = 0, or by using POSIX::setuid.

Having said that, you may want to get rid of perl-suid, as it has been deprecated for some time, and gotten rid of in 5.12. You're probably better of either using sudo, or putting the appropriate magic in your /etc/fstab so a file system can be mounted by a non-root user. For instance, on my home boxes, I have:

/dev/sdb1      /mnt/sdb1     auto    use    0 0
/dev/sdb2      /mnt/sdb2     auto    user   0 0

in my /etc/fstab file, allowing a non-root user to mount usb devices.

[Anonymous Monk]

$< = 0 made it, at least until perl 5.12. I had not expected that I was allowed to do that, so I didn't try this obvious step.

Thanks a lot!

Unfortunately, neither sudo nor fstab can help. It is required that user A cannot access the media of user B. fstab solutions would at best bind a user to some device node, which is determined by the order of plugging the device and does not relate to users.

In principle I could define a whole bunch of sudo rules per user, but this would require to rewrite the /etc/sudoers on all systems, whenever the central user LDAP changes. Such things tend to be unmaintainable.

[zentara]

If sudo or fstab won't help, you are probably at the point of having to make a special group, whose purpose it is to run that script/device. Then add that group to allowed users.

This is from memory, but I'm sure Ubuntu allows it's users to run mount via sudo

sudo mount -t ext4 ....etc,etc

so I don't think any sort of filesystem permission checking stops mount by non-root users. Ubuntu may even have a group called mount. ?