linux-kernel - Re: ksmbd: Unsupported addition info

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Date:   Wed, 17 Nov 2021 00:23:22 +0100
From:   Oleksandr Natalenko <oleksandr@...alenko.name>
To:     Marios Makassikis <mmakassikis@...ebox.fr>
Cc:     Namjae Jeon <linkinjeon@...nel.org>,
        Sergey Senozhatsky <senozhatsky@...omium.org>,
        Steve French <sfrench@...ba.org>,
        Hyunchul Lee <hyc.lee@...il.com>,
        CIFS <linux-cifs@...r.kernel.org>, linux-kernel@...r.kernel.org
Subject: Re: ksmbd: Unsupported addition info

Hello.

Thanks for your response. Please find my answers inline.

On středa 17. listopadu 2021 0:03:34 CET Marios Makassikis wrote:
> On Tue, Nov 16, 2021 at 10:44 PM Oleksandr Natalenko
> 
> <oleksandr@...alenko.name> wrote:
> > Hello Namjae et al.
> > 
> > With the latest ksmbd from the next branch I have an issue with wife's
> > Windows 10 laptop while copying/removing files from the network share. On
> > her client it looks like copy operation (server -> laptop) reaches 99%
> > and then stalls, and on the server side there's this in the kernel log:
> > 
> > ```
> > ksmbd: Unsupported addition info: 0xf)
> > ksmbd: Unsupported addition info: 0x20)
> > ```
> > 
> > repeated multiple times. I must note that in fact the file gets copied to
> > her laptop, but Windows copy dialog just hangs.
> > 
> > Any idea what it could be and how to avoid it? This also happened before
> > (I'm a pretty early ksmbd adopter), but I'm reporting it just now because
> > I naïvely hoped it would be fixed automagically :). This never happened
> > to me with userspace Samba though.
> > 
> > This is my smb.conf:
> > 
> > ```
> > [global]
> > workgroup = KANAPKA
> > server string = ksmbd server %v
> > netbios name = defiant
> > valid users = __guest
> > 
> > [Shared]
> > valid users = __guest
> > path = /mnt/shared
> > force user = _shared
> > force group = _shared
> > browsable = no
> > writeable = yes
> > veto files = /lost+found/
> > ```
> > 
> > Appreciate your time and looking forward to your response.
> 
> This sounds like an issue reported on github a couple of months ago [1].
> 
> Can you specify the exact Windows version (+ edition) ?

It is Windows 10 Pro 21H1 19043.1348

> Are you accessing the share through a network-mapped drive ? If not,
> can you try to reproduce it ?

Yes, the share is "mounted" as a network-mapped drive Z:.

> Does this happen with files of any type ?

I didn't find it depending on a specific file type. Just tried a couple of fresh 
jpgs and xslx, all hung, but another pair of old jpgs went fine instantly, 
although the same message was logged in the kernel log on the server side for 
all the files.

> IIRC, the "Unsupported addition
> info" message you're seeing is related to Windows requesting some
> attributes that are not handled yet by ksmbd. It seems it was added to fix
> windows 10 clients
> after ACLs support was added [2]. Makes me wonder if Windows doesn't like
> the fake response it is getting when it's trying to read the SACLs.

Cannot comment on this since I have no idea how things work or are supposed to 
work, but I'm ready to test patches as well as ksmbd options if there are some 
suggestions.

Thanks you!

> https://github.com/cifsd-team/ksmbd-tools/issues/208
> https://github.com/namjaejeon/ksmbd/commit/cb9167856ffca6483

-- 
Oleksandr Natalenko (post-factum)