[OpenIndiana-discuss] samba4

[Peter Tribble]

On Wed, Mar 19, 2025 at 8:45 AM Maurilio Longo via openindiana-discuss <
openindiana-discuss at openindiana.org> wrote:

> Hi Udo,
>
> glad you can confirm the issue.
>

I can see it on Tribblix with samba 4.18.11. Based on that:

The failing code is quite simple from the perspective of truss. Here are
the 2 lines that matter:

openat(15, "tt", O_RDONLY|O_NONBLOCK|O_NOFOLLOW) = 29
...
open("/proc/self/fd/29", O_RDWR|O_NONBLOCK|O_CREAT, 0644) Err#13 EACCES
[proc_owner]

OK, so it opens the file read-only, and gets a file descriptor. It then
opens that file
descriptor read-write. (Oh, and the first open is as root, the 2nd as the
user.) It's trivial to
write a quick test that just does the 2 opens in a row with those flags,
and it fails the same way.

This is why it only fails on existing files, because only then do you have
the first read-only open().

Looking at the samba history, I think all this came about in the vfs
rewrite in 4.14.

What I haven't managed to identify yet is where the code needs fixing.


> I see there are several patches for samba floating around like these
>
>
> https://illumos.topicbox.com/groups/omnios-discuss/Tdb139e16df7ad3e5-Mc3b299137ec346ee7c862243/samba-4-on-omnios
>
> Probably they were not submitted to samba.org and we're now 10 minor
> releases behind, which could make it a big task to reconcile everything and
> have an up to date working package.
>
> Best regards.
>
> Maurilio.
>
> > Il 18/03/2025 11:30 CET Udo Grabowski (IMKASF) <udo.grabowski at kit.edu>
> ha scritto:
> >
> >
> > On 18-03-2025 11:05, Maurilio Longo via openindiana-discuss wrote:
> > > Ok,
> > > so, having an OmniOS VM around and having OmniOS several versions of
> samba available I was able to test versions 4.17 and 4.10.
> > >
> > > 4.10 works as expected (at least as far as permission handling is
> concerned) and I can overwrite a file without problems without using NFSV4
> ACLs, but with the simple solarisacl vfs.
> > >
> > >...
> > >
> > > So, I can say that samba packages past version 4.10.18 are broken,
> from the log.smbd I can see that write is never allowed on an existing file
> even if owner/group/others have write permission.
> > >
> > > So the question becomes, is there a samba maintainer for
> Illumos/OmniOS/Openindiana that I can contact to inform that something is
> not working as
> >
> > > expected or at least to ask for the removal of the samba packages past
> 4.10.18 being that they're broken?
> >
> > Can confirm the broken behaviour for client 4.20.2-2024.0.0.0, as
> > delivered by OI Hipster 2024:07:17, and server 4.21.1.-2024.0.0.0 as
> > delivered by OI Hipster 2025.01.13. Files can be created and removed,
> > but not overwritten or extended via smbclient:
> > smb: \> put /tmp/tt t
> > NT_STATUS_ACCESS_DENIED opening remote file \t
> > smb: \> rm t
> > smb: \> put /tmp/tt t
> > putting file /tmp/tt as \t (2.9 kb/s) (average 0.7 kb/s)
> > smb: \> reput /tmp/tt t
> > NT_STATUS_ACCESS_DENIED opening remote file \t
> >
> > --
> > Dr.Udo Grabowski  Inst.of Meteorology & Climate Research IMKASF-SAT
> > https://www.imk-asf.kit.edu/english/sat.php
> > KIT - Karlsruhe Institute of Technology          https://www.kit.edu
> > Postfach 3640,76021 Karlsruhe,Germany T:(+49)721 608-26026 F:-926026
> >
> > _______________________________________________
> > openindiana-discuss mailing list
> > openindiana-discuss at openindiana.org
> > https://openindiana.org/mailman/listinfo/openindiana-discuss
>
> _______________________________________________
> openindiana-discuss mailing list
> openindiana-discuss at openindiana.org
> https://openindiana.org/mailman/listinfo/openindiana-discuss
>


-- 
-Peter Tribble
http://www.petertribble.co.uk/ - http://ptribble.blogspot.com/