Re: kernel-5.18.8 breaks cifs mounts

["Georg Müller" <georgmueller@gmx.net>]

Hi,

Am 12.07.22 um 06:36 schrieb Steve French:
> I was able to reproduce it to older Samba server (4.12.5) and could
> workaround the Samba server bug by using mount option "compress" on
> the client (which won't do anything different since it is not
> supported but  interestingly it avoids the problem by adding another
> context at the end).


The general problem might be solved by just moving the now optional hostname
context in fs/cifs/smb2pdu.c back between build_encrypt_ctxt and build_posix_ctxt.

I encounter the issue with a Synology Diskstation, and there might be
much more people running into the problem when this kernel becomes more
common...


> On Wed, Jul 6, 2022 at 6:18 AM Julian Sikorski <belegdol@gmail.com> wrote:
>>
>> Am 04.07.22 um 18:29 schrieb Julian Sikorski:
>>>
>>>
>>> Am 03.07.22 um 19:51 schrieb Stefan Metzmacher:
>>>> Am 03.07.22 um 07:01 schrieb Steve French:
>>>>> I lean toward thinking that this is a Samba bug (although I don't see
>>>>> it on my local system - it works to samba for me, although I was
>>>>> trying against a slightly different version, Samba 4.15.5-Ubuntu).
>>>>>
>>>>> Looking at the traces in more detail they look the same (failing vs.
>>>>> working) other than the order of the negotiate context, which fails
>>>>> with POSIX as the 3rd context, and netname as the 4th, but works with
>>>>> the order reversed (although same contexts, and same overall length)
>>>>> ie with POSIX context as the fourth one and netname context as the
>>>>> third one.
>>>>>
>>>>> The failing server code in Samba is in
>>>>> smbd_smb2_request_process_negprot but I don't see changes to it
>>>>> recently around this error.
>>>>>
>>>>> Does this fail to anyone else's Samba version?
>>>>>
>>>>> This is probably a Samba server bug but ... seems odd since it doesn't
>>>>> fail to Samba for me.
>>>>>
>>>>> Jeremy/Metze,
>>>>> Does this look familiar?
>>>>
>>>> Maybe this one:
>>>>
>>>> https://git.samba.org/?p=samba.git;a=commitdiff;h=147dd9d58a429695a3b6c6e45c8b0eaafc67908a
>>>>
>>>>
>>>> that went only into 4.15 and higher.
>>>>
>>>> metze
>>>
>>> Nice catch, I can confirm that adding this patch to debian samba
>>> 2:4.13.13+dfsg-1~deb11u3 package makes the mounts work again. How do we
>>> get this patch into debian?
>>>
>>> Best regards,
>>> Julian
>> I have now filed a bug against debian samba package:
>> https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1014453
>>
>> Best regards,
>> Julian
>
>
>