Bug 355247

Summary: reluctant mount coreutil
Product: [openSUSE] SUSE Linux 10.1 Reporter: Elmar Stellnberger <estellnb>
Component: BasesystemAssignee: Matthias Koenig <mkoenig>
Status: RESOLVED WONTFIX QA Contact: E-mail List <qa-bugs>
Severity: Enhancement    
Priority: P4 - Low    
Version: Final   
Target Milestone: ---   
Hardware: i686   
OS: SuSE Linux 10.1   
Whiteboard:
Found By: Community of Practice Services Priority:
Business Priority: Blocker: ---
Marketing QA Status: --- IT Deployment: ---

Description Elmar Stellnberger 2008-01-22 11:32:35 UTC 
user mode mounts can cause a lot of problems:

1.) remount is supposed to succeed if mount succeeds:
> mount /mnt/ram
> mount -o remount /mnt/ram
mount: Nur „root“ kann dies tun

2.) umount is refused if dev is mounted several times by user
> mount|grep ram
/dev/ram1 on /mnt/ram type ramfs (rw,noexec,nosuid,nodev)
/dev/ram1 on /mnt/ram type ramfs (rw,noexec,nosuid,nodev)
> umount /mnt/ram
umount: /mnt/ram scheint mehrfach eingehängt zu sein
> mount|grep ram
/dev/ram1 on /mnt/ram type ramfs (rw,noexec,nosuid,nodev)
/dev/ram1 on /mnt/ram type ramfs (rw,noexec,nosuid,nodev)

3.) privileges of user mount point remain reset
> ls -ld /mnt/ram
drwxrwxrwx 3 elm users 72 2007-06-05 10:39 /mnt/ram
> mount /mnt/ram
> ls -ld /mnt/ram
drwxr-xr-x 2 root users 0 2008-01-22 12:27 /mnt/ram
> chown elm:users /mnt/ram
chown: Ändern des Eigentümers von „/mnt/ram“: Die Operation ist nicht erlaubt
> sudo chown elm:users /mnt/ram
root's password:
> ls -ld /mnt/ram
drwxr-xr-x 2 elm users 0 2008-01-22 12:27 /mnt/ram
> grep ram /etc/fstab
/dev/ram1             /mnt/ram             ramfs      noauto,user       0 0

Consequently it is possible to mount /dev/ram1 as user, but not to access /dev/ram1 after mounting unless a root user resets the privileges of the mount point. That simply does not make sense. I would suggest mount to execute a chown for user mounts ('user' or 'users' mount option) on the mount point and additionally a chmod g+u for mounts with the 'users' option on the mount point.
Comment 1 Matthias Koenig 2008-05-13 14:36:48 UTC 
1. Currently mount disallows remounts for user, because you are able to change options when remounting and user mounts have their options defined in fstab.
If you want to allow this you will have to keep track which options should be allowed on remount.
As such a feature would require much work, please discuss this upstream on the util-linux-ng mailing list (util-linux-ng@vger.kernel.org).

2. The issue here is that the same  device has been mounted several times on the same mount point, this is fixed in the current release of util-linux-ng.

3. The permissions of the mount point are completely irrelevant. The user/group/permissions which show up are given in the filesystem which is to be mounted. I do not think that mount should touch the filesystem via chown/chmod.