[Samba] Strange logs: check_usershare_stat: file /var/lib/samba/usershares/ owned by uid 0 is not a regular file

[Roy Eastwood]

Thanks Andrew for your quick reply.

Here are the results of those commands:

root at lxd-m1:~# ls -l /var/lib/samba/usershares
total 0
root at lxd-m1:~# ls -l /var/lib/samba/
total 136
-rw------- 1 root root          421888 Jun 16 19:18 account_policy.tdb
drwxr-xr-x 1 root root              36 Jul 19  2019 DriverStore
-rw------- 1 root root          425984 Jul 19  2019 group_mapping.tdb
drwxr-xr-x 1 root root              98 Jul 19  2019 printers
drwxr-xr-x 1 root root             124 Jul 19  2019 private
-rw------- 1 root root          528384 Jul 19  2019 registry.tdb
-rw------- 1 root root          421888 Jul 21  2019 share_info.tdb
drwxrwx--T 1 root sambashare         0 Jul 19  2019 usershares
-rw------- 1 root root           32768 Dec  1 19:57 winbindd_cache.tdb
-rw-r--r-- 1 root root          421888 Jul 20  2019 winbindd_idmap.tdb
drwxr-x--- 1 root winbindd_priv      8 Nov  4 17:08 winbindd_privileged
root at lxd-m1:~# stat  /var/lib/samba/usershares
  File: /var/lib/samba/usershares
  Size: 0               Blocks: 0          IO Block: 4096   directory
Device: 41h/65d Inode: 24656       Links: 1
Access: (1770/drwxrwx--T)  Uid: (    0/    root)   Gid: (  111/sambashare)
Access: 2020-12-01 19:00:10.120922818 +0000
Modify: 2019-07-19 12:14:08.718571118 +0100
Change: 2020-01-17 09:43:21.506782092 +0000
 Birth: -
root at lxd-m1:~#

As far as I know I'm not using usershares.   There are no usershare directives in smb.conf which is as follows:
root at lxd-m1:~# cat /etc/samba/smb.conf
[global]

        netbios name = lxd-m1
        security = ADS
        workgroup = MICROLYNX
        realm = MICROLYNX.ORG

        # disable smb1
        client min protocol = smb2_02
        server min protocol = smb2_02

        log file = /var/log/samba/%m.log
        log level = 1

        # to prevent "Address family not supported by protocol" messages (ipv6)
        bind interfaces only = yes
        interfaces = lo eth0

        dedicated keytab file = /etc/krb5.keytab
        kerberos method = secrets and keytab
        winbind refresh tickets = yes

        winbind use default domain = yes

        # Default idmap config used for BUILTIN and local accounts/groups
        idmap config *:backend = tdb
        idmap config *:range = 2000-9999

        # idmap config for domain MICROLYNX
        idmap config MICROLYNX:backend = rid
        idmap config MICROLYNX:range = 10000-99999

        # next two lines for testing only - comment-out once working ok
        # winbind enum users = yes
        # winbind enum groups = yes

        template shell = /bin/bash
        template homedir = /srv/samba/users/%U

        vfs objects = acl_xattr
        map acl inherit = yes
        store dos attributes = yes
        username map = /etc/samba/user.map

[profiles]
        # user profiles folder for roaming profiles
        path = /srv/samba/profiles
        read only = no
        acl_xattr:ignore system acl = yes
        vfs objects = btrfs

[users]
        # user homedirs
        path = /srv/samba/users
        read only = no
        acl_xattr:ignore system acl = yes
        vfs objects = btrfs
        # Recyle bin
        recycle:repository = %U/Recycle_Bin
        recycle:versions = Yes
        recycle:keeptree = Yes
        recycle:touch = Yes
        recycle:exclude = *.tmp,~$*
        recycle:exclude_dir = %U/Recycle_Bin

I don't see any other side effects - the box seems to be operating normally as far as I can tell.

Regards,
Roy
> -----Original Message-----
> From: Andrew Bartlett <abartlet at samba.org>
> Sent: 01 December 2020 17:28
> To: Roy Eastwood <spindles7 at gmail.com>; samba at lists.samba.org
> Subject: Re: [Samba] Strange logs: check_usershare_stat: file /var/lib/samba/usershares/ owned by uid 0 is not a regular file
> 
> On Tue, 2020-12-01 at 14:30 +0000, Roy Eastwood via samba wrote:
> > These logs:
> >
> > 	Dec  1 09:31:16 lxd-m1 smbd[26323]:   check_usershare_stat:
> > file /var/lib/samba/usershares/ owned by uid 0 is not a regular file
> >
> > have started to appear this morning in sysvol.   25 such logs
> > appeared within a minute.  No changes have been made for some time on
> > this machine.  It's a member server running samba 4.13.2 on Debian
> > Buster.    Is this a known bug?
> 
> So first question:  What is it?
> 
> That is, Samba gives this error, so what does a manual shell inspection with ls -l and stat etc give?
> 
> Usershare functionality is configured via your smb.conf.
> 
> Andrew Bartlett
> 
> --
> Andrew Bartlett (he/him)       https://samba.org/~abartlet/
> Samba Team Member (since 2001) https://samba.org
> Samba Team Lead, Catalyst IT   https://catalyst.net.nz/services/samba
>