[Samba] Cannot delete/write after system update

Rowland Penny
Mon, 27 Apr 2015 09:56:05 -0000

On 26/04/15 05:38, Bob Bell wrote:
> After upgrading one of my home servers, and I can no longer delete or
> write files via Samba.  I would very much appreciate assitance.  I
> will explain my situation and provide logs for the case of deleting a
> simple file.
>
> My configuration is to access my shares as a guest, which should be
> mapped to the smbuser Linux account.
>
> To achieve this I have set the following globally:
>  map to guest = Bad Password ## I added this after the upgrade, to
> replace "security = share"
>  guest ok = yes
>  guest account = smbuser
>
> And the following on my share:
>  public = yes
>  writeable = yes
>  guest ok = yes ## Redundant, I guess
>  create mask = 0664
>  directory mask = 6775
>
> My desire is that if a directory is writable by the smbuser group,
> then it is writable via Samba.  But this is not what I see (since the
> upgrade).
>
> If I create a directory owned by smbuser:smbuser with 0777
> permissions, I can upload a file, and delete the same file (using
> smbclient).  The uploaded file is owned by smbuser:smbuser, confirming
> (to me) that the mapping to guest is functioning correctly.
>
> However, if I remove the other write permission (i.e., drop
> permissions to 0775), I can no longer delete files or write files.  I
> get an NT_STATUS_ACCESS_DENIED error.
>
> I'm a seasoned programmer, and I've actually spent hours tried to
> debug this, but I am coming up short.  I can see that the
> NT_STATUS_ACCESS_DENIED is coming from se_access_check(), because the
> delete bit is not cleared, but I really lack the context to understand
> WHY.  I would greatly appreciate your assistance.
>
> I've run through as simple an interaction as I can think of: using
> smbclient to attempt to delete a "deleteme" file.  I set debug
logging
> to 10 for this example, and collected a client-specific log.  I
> believe the key log line may be line 1599:
>
> [2015/04/26 00:07:17.457393, 10, pid=22294, effective(1001, 1001),
> real(1001, 0)] ../source3/smbd/open.c:171(smbd_check_access_rights)
>  smbd_check_access_rights: file deleteme requesting 0x10000 returning
> 0x10000 (NT_STATUS_ACCESS_DENIED)
>
> Note that the smbuser UID is 1001, and the smbuser GID is 1001.
>
> I've uploaded the full log file to http://n01se.net/paste/Kmz for
> anyone who would be so kind to offer their expertise.
>
> Thank you in advance,
> Bob

Any chance you can post your smb.conf ?

Rowland