Permissions – Fix CIFS Mounted NAS Box Permission Issues

permissionssamba

I'm running the latest version of Ubuntu, and have mounted a SMB share via a line in rc.local.

The share mounts correctly, and I can browse files freely, create new files, and then delete them without problems.

But when I try and rsync a directory onto the mounted share:

rsync -a --delete /MySource/ /SharedMountPoint/

I get lots of errors:

rsync: failed to set times on "/SharedMountPoint/SomeDir": Operation not permitted (1)

and similar errors about being unable to create temp files.

All the files and directories on the share are listed with numeric uid/guid – which I suppose is reasonable, as they were originally created via a sync from a windows box.

I have no great need for access control – its just a box on a LAN that me and my family use as a dropbox – I'd basically just like anyone to be able to access it (provided they've done basic authentication).

Best Answer

When mounting, use -o uid=youruid. Then, all files on that cifs share will be owned by you so that you can edit/remove them.
E.g.:

mount -o uid=1000 //nas/share /SharedMountPoint

You can find your numeric uid in /etc/passwd

grep `whoami` /etc/passwd | cut -d : -f 3

or:

id -u `whoami`

Related Solutions

Linux – Make all files under a directory read-only without changing permissions

This answer works on Debian (tested on lenny and squeeze). After investigation, it seems to work only thanks to a Debian patch; users of other distributions such as Ubuntu may be out of luck.

You can use mount --bind. Mount the “real” filesystem under a directory that's not publicly accessible. Make a read-only bind mount that's more widely accessible. Make a read-write bind mount for the part you want to expose with read-write access.

mkdir /media/hidden /media/hidden/sdz99
chmod 700 /media/hidden
mount /dev/sdz99 /media/hidden/sdz99
mount -o bind,ro /media/hidden/sdz99/world-readable /media/world-readable
mount -o bind /media/hidden/sdz99/world-writable /media/world-writable

In your use case, I think you can do:

mkdir /var/smb/hidden
mv /var/smb/snapshot /var/smb/hidden
mkdir /var/smb/snapshot
chmod 700 /var/smb/hidden
chmod 755 /var/smb/hidden/snapshot
mount -o bind,ro /var/smb/hidden/snapshot /var/smb/hidden/snapshot

I.e. put the real snapshot directory under a restricted directory, but give snapshot read permissions for everyone. It won't be directly accessible because its parent has restricted access. Bind-mount it read-only in an accessible location, so that everyone can read it through that path.

(Read-only bind mounts only became possible several years after bind mounts were introduced, so you might remember a time when they didn't work. I don't know offhand since when they work, but they already worked in Debian lenny (i.e. now oldstable).)

Cannot mount samba share: Mount error (22)

Try adding sec=ntlm to your option flags for mount, eg sudo mount -t cifs -o user=user,sec=ntlm //server/share /mnt/sth. Solved the same problem for me.

Source: https://bbs.archlinux.org/viewtopic.php?id=160047

Best Answer

Related Solutions

Linux – Make all files under a directory read-only without changing permissions

Cannot mount samba share: Mount error (22)

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