samba - Dec 2012 - Read only behaviour of a file when opened two or more times.

Hello,
My samba server (version samba-3.0.33-3.39.el5_8) on CentOS 5.8 (kernel
2.6.18-308.1.1.el5) opens files as read only once it has been opened from the
second time onwards.  The first time the file is opened, it is possible to edit
the file and save these changes.  Once the file has been closed and then opened
again, it is opened as a read only file and when making changes, it is not
possible to save using the same file name however a different name needs
specifying (save as).
In smbd.log I see some of the following, sanitised:

Works:-
[2012/12/19 22:10:48, 4] smbd/open.c:open_file_ntcreate(1605)
  calling open_file with flags=0x2 flags2=0x0 mode=0744, access_mask = 0x20196,
open_access_mask = 0x20196
[2012/12/19 22:10:48, 2] smbd/open.c:open_file(391)
  USER opened file FILE read=No write=Yes (numopen=2)

Doesn't work:-
[2012/12/19 22:10:48, 3] smbd/vfs.c:reduce_name(922)
  reduce_name: FILE reduced to /path/FILE
[2012/12/19 22:10:48, 4] smbd/open.c:open_file_ntcreate(1605)
  calling open_file with flags=0x0 flags2=0x0 mode=0744, access_mask = 0x20089,
open_access_mask = 0x20089
[2012/12/19 22:10:48, 2] smbd/open.c:open_file(391)
  USER opened file FILE read=Yes write=No (numopen=2)

Note the difference in access_mask and open_access_mask.

This is something that has recently developed, my colleagues nor I have made
changes to the samba config.  The windows attributes on the file do not have
'read only' checked.  The share is an nfs export from a netapp, again,
no configurations have been made.  'read only = No', 'map read-only
= no' and 'readonly = no' has been set in /etc/samba/smb.conf.

Has anyone seen this kind of behaviour?
Help would be greatly appreciated, thanks in advance.

Regards,
Sebastien

S?bastien Torres
Desktop Administrator ? GlobalIT - PGS<http://www.pgs.com/>
T: +44 1 932 376 505  | M: +44 7 787 743 974 | VOIP: 74416505

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