samba - Jan 2016 - strange behavior with "dos filetime resolution = yes"

Hello,

i see a strange behavior with timestamps of files on a samba share 
(4.2.6 on SLES 12 SP1 and 4.1.8 on Ubuntu 14.04) with "dos filetime 
resolution = yes": On older samba versions, windows properties dialogue 
correctly shows only even seconds, but (at least) the two indicated 
versions show sometimes even and sometimes odd seconds if the file has 
on the server filesystem a timestamp with second.

on SLES (file has odd seconds in timestamp):
  # l --full-time fsclean_kunde.sh
-rwxrwxr-x 1 relag relag 1930 2016-01-21 18:08:41.280635200 +0100 
fsclean_kunde.sh*

on Windows 7 (seconds should be 40!):
T:\projekte\relag4i\RelagSystem\cmd>ls -l --full-time 
T:\projekte\relag4i\RelagSystem\cmd\fsclean_kunde.sh
-rw-r--r--    1 hubert   Administ     1930 Thu Jan 21 17:08:41 2016 
T:\projekte\relag4i\RelagSystem\cmd\fsclean_kunde.sh

But when you view properties via Windows Explorer, it reports 
alternately 41 and 40 seconds.

In my understanding, "dos filetime resolution = yes" should have the 
effect that only even seconds are reported by samba (and in older 3.x 
version this is the case).

smb.conf (only the relevant share):
[RELAG]
         force group = relag
         force user = relag
         # inherit acls = Yes
         path = /relag
         create mask = 0775
         directory mask = 0775
         follow symlinks = yes
         wide links = yes
         read only = No
         dos filemode = Yes
         dos filetimes = Yes
         dos filetime resolution = Yes
         fake directory create times = yes
         map archive = no

-- 
Mit freundlichem Gruß
i. A. Hubert Gilch

Systemadministrator

SEP Logistik AG
Ziegelstr. 2
D-83629 Weyarn
Tel.:     +49 8020 905-214
Fax:     +49 8020 905-100
Email: hg at sepag.de <mailto:hg at sepag.de>
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München: HRB 119679
Vorstand: Professor Dr.-Ing. Franz Demmelmeier (Vorsitzender), 
Dipl.-Ing. Konrad Schneider, MBA, Dipl.-Ing. Markus Fischbacher
Aufsichtsratsvorsitzender Michael Pelzer

On Tue, Jan 26, 2016 at 11:57:58AM +0100, Hubert Gilch
wrote:
> Hello,
> 
> i see a strange behavior with timestamps of files on a samba share
> (4.2.6 on SLES 12 SP1 and 4.1.8 on Ubuntu 14.04) with "dos filetime
> resolution = yes": On older samba versions, windows properties
> dialogue correctly shows only even seconds, but (at least) the two
> indicated versions show sometimes even and sometimes odd seconds if
> the file has on the server filesystem a timestamp with second.
> 
> on SLES (file has odd seconds in timestamp):
>  # l --full-time fsclean_kunde.sh
> -rwxrwxr-x 1 relag relag 1930 2016-01-21 18:08:41.280635200 +0100
> fsclean_kunde.sh*
> 
> on Windows 7 (seconds should be 40!):
> T:\projekte\relag4i\RelagSystem\cmd>ls -l --full-time
> T:\projekte\relag4i\RelagSystem\cmd\fsclean_kunde.sh
> -rw-r--r--    1 hubert   Administ     1930 Thu Jan 21 17:08:41 2016
> T:\projekte\relag4i\RelagSystem\cmd\fsclean_kunde.sh
> 
> But when you view properties via Windows Explorer, it reports
> alternately 41 and 40 seconds.
> 
> In my understanding, "dos filetime resolution = yes" should have
the
> effect that only even seconds are reported by samba (and in older
> 3.x version this is the case).
> 
> smb.conf (only the relevant share):
> [RELAG]
>         force group = relag
>         force user = relag
>         # inherit acls = Yes
>         path = /relag
>         create mask = 0775
>         directory mask = 0775
>         follow symlinks = yes
>         wide links = yes
>         read only = No
>         dos filemode = Yes
>         dos filetimes = Yes
>         dos filetime resolution = Yes
>         fake directory create times = yes
>         map archive = no
Can you get a wireshark trace when you're asking
for the properties ? The lp_dos_filetime_resolution()
check isn't widely used or tested so there might
be a path through that no longer does the rounding.

Seeing what call is being made should help track
that down.

Cheers,

	Jeremy.

Hello Jeremy,

thank you for your reply
> Can you get a wireshark trace when you're asking
> for the properties ? The lp_dos_filetime_resolution()
> check isn't widely used or tested so there might
> be a path through that no longer does the rounding.
I ran a trace when i opened the windows properties dialogue two times, 
the first one got me an even second (40), the second one an odd second 
(41). I wanted the two cases in different traces but didn't succeed. 
After the time it took me to start a second trace i always got 40. It 
seems that the alternating 40/41 seconds occur only when requesting the 
file properties again after relatively short time.

You can download the trace here: 
https://proximus.sepag.de/properties_fsclean_kunde.sh.pcap.gz
I also provided a client logfile (loglevel 4) with the same sequence, 
but from a later time: https://proximus.sepag.de/log.peleus.gz

Mit freundlichem Gruß
i. A. Hubert Gilch