cifs mounts: unable to move dangling symlinks (case of svn ceckout with symlinks)

[casbon]

Binary package hint: smbfs

Sometimes, a cifs mount refuses to remove an empty directory. It can easily be removed on the samba server, but not on the client.

james@palermo:~/lib/.svn$ mount
...
//newyork/james on /home/james type cifs (rw,mand)
...
james@palermo:~/lib/.svn$ ls -al tmp/
total 0
drwxr-xr-x 2 james james 0 2007-05-30 11:22 .
drwxr-xr-x 3 james james 0 2007-05-30 11:22 ..
james@palermo:~/lib/.svn$ rm tmp/
rm: cannot remove `tmp/': Is a directory
james@palermo:~/lib/.svn$ rmdir tmp/
rmdir: tmp/: Directory not empty
james@palermo:~/lib/.svn$ rm -rf tmp/
rm: cannot remove directory `tmp/': Directory not empty

[casbon (casbon)]

This seems to be due to the fact that samba refuses to show dangling symlinks:

james@palermo:~$ mkdir test1
james@palermo:~$ touch test1/dest
james@palermo:~$ ln -s test1/dest test1/link
james@palermo:~$ rm test1/dest
james@palermo:~$ ls -l test1/
total 0
james@palermo:~$ rmdir test1
rmdir: test1: Directory not empty

[Mathias Gug (mathiaz)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Could you specify which version of smbfs you're using ?

[casbon (casbon)]

version on client: 3.0.24-2ubuntu1

version of samba on server: 3.0.22-1ubuntu3

[Mathias Gug (mathiaz)]

I cannot reproduce your problem here.

On Thu, Sep 20, 2007 at 10:54:29AM -0000, casbon wrote:
> version on client: 3.0.24-2ubuntu1
>
> version of samba on server: 3.0.22-1ubuntu3
>

Could you try updating to the latest version of samba ? The versions
you've reported are not the latest security updates for both feisty and
dapper.

[casbon (casbon)]

I updated the packages to the latest for dapper ( samba 3.0.22-1ubuntu3.3) and feisty (3.0.24-2ubuntu1.2).

Still seeing the problem:

james@palermo:~$ mkdir bug
james@palermo:~$ touch bug/real
james@palermo:~$ ln -s bug/real bug/link
james@palermo:~$ rm bug/real
james@palermo:~$ ls -l bug/
total 0
james@palermo:~$ rm -rf bug/
rm: cannot remove directory `bug/': Directory not empty
james@palermo:~$ rm bug/link
james@palermo:~$ rm -rf bug/
james@palermo:~$

[Mathias Gug (mathiaz)]

Can you post the smb.conf file from the dapper server ? and the line that mounts the cifs share in fstab in the feisty client ?

[casbon (casbon)]

Its mounted through pam mount, not fstab:

in /etc/security.d/pam_mount:
volume * cifs newyork & /home/& severino - -

from mount command:
//newyork/james on /home/james type cifs (rw,mand)

[Mathias Gug (mathiaz)]

On Fri, Sep 21, 2007 at 04:41:24PM -0000, casbon wrote:
> Its mounted through pam mount, not fstab:
>
> in /etc/security.d/pam_mount:
> volume * cifs newyork & /home/& severino - -
>
> from mount command:
> //newyork/james on /home/james type cifs (rw,mand)
>

Could you try with an fstab entry or manually mounting the share ?

[casbon (casbon)]

Still the same problem:
james@palermo:/mnt$ tail -1 /etc/fstab
//newyork/james /mnt/test cifs user=james
james@palermo:/mnt$ sudo mount test/
Password:
james@palermo:/mnt$ cd test/
james@palermo:/mnt/test$ mkdir bug
james@palermo:/mnt/test$ touch bug/real
james@palermo:/mnt/test$ ln -s bug/real bug/link
james@palermo:/mnt/test$ rm bug/real
james@palermo:/mnt/test$ ls bug/
james@palermo:/mnt/test$ rm -rf bug/
rm: cannot remove directory `bug/': Directory not empty
james@palermo:/mnt/test$ rm bug/link
james@palermo:/mnt/test$ rm -rf bug/

[Mathias Gug (mathiaz)]

Looking at your smb.conf file, you've enabled the option "hide unreadable" in the general section :

[global]

..

hide unreadable = yes

That's the reason why dangling symlinks are not listed on the client.

[casbon (casbon)]

Ok thanks, that shows the link. Unfortunately, now I cannot move a broken symlink.

james@palermo:~/bug$ rm *
james@palermo:~/bug$ touch real
james@palermo:~/bug$ ln -s real link
james@palermo:~/bug$ rm real
james@palermo:~/bug$ mv link link2
mv: cannot move `link' to `link2': No such file or directory
james@palermo:~/bug$ ls -l
total 0
lrwxrwxrwx 1 james james 4 2007-09-23 20:48 link -> real

BTW - why I am trying to do this? svn does not work on cifs partitions because of this error. If it checks out a directory with links in, it moves the real file before the link, and the breaks because the link won't move.

[Mathias Gug (mathiaz)]

I can reproduce your problem. Thanks for giving the reason why you're trying to do that.

nfs doesn't have this problem. Could you use nfs instead of cifs to mount your home from your client ?

[Laurent Dinclaux (dreadlox)]

Using NFS is not a fix but a workaround and NFS is not to be not so secure....

CIFS has broken symlink support as I can browse the symlinks using nautilus (smb://) and not using CIFS (for the same share)

[spencerrecneps (spencerjgardner)]

Has anything ever been done with this bug? I'm running into the same issue and can't find a satisfactory response anywhere online.

[Fredrik Persson (frepe)]

I am experiencing this same bug right now. Has anything been done to correct it? I have not been able to find a solution online either.

[Marcerino (mastervanleeuwen)]

I've also exprienced this problem, although for a different reason. The problem seems to have been fixed in recent versions (3.3.x) of samba. See:
https://bugzilla.samba.org/show_bug.cgi?id=6090

I tested removing dangling symlinks using Ubuntu 8.10 (Intrepid Ibex) as a server and that seems to work. As far as I understand, that should mean that moving them also works.

As an aside: I am interested in this issue because I would like to pam_mount homedirs using cifs. firefox creates a lock file that is a dangling symlink. If the lock file cannot be removed, firefox cannot be started...

[casbon (casbon)]

2009/4/10 Marcerino <email address hidden>:
> As an aside: I am interested in this issue because I would like to
> pam_mount homedirs using cifs. firefox creates a lock file that is a
> dangling symlink. If the lock file cannot be removed, firefox cannot be
> started...

Last time I tried firefox uses sqlite, which thinks all databases are
locked if they're opened on cifs.

[Thierry Carrez (ttx)]

This should have been fixed in 3.3.1, so the problem should be gone in Jaunty.
Could anyone affected please confirm that this is fixed in Jaunty ?

[lordlaurin (lordlaurin)]

I've just upgraded to Jaunty and I am still experiencing this problem.

[cult_hero13 (cult-hero13)]

I have a samba server set up on a very up-to-date build of Gentoo and am accessing it using a samba client on SuSE 10.0 OSS. I have the exact same problem with Firefox and Thunderbird lock files not being removed.

I can also replicate it by creating a file, creating a symlink to it, then removing the file. I will not be able to remove the symlink on the client side, but I can on the server.