ACK/Cmnt: [PATCH 0/14][Focal,Groovy][linux] Enable CIFS GCM256

[Tim Gardner]

On 5/5/21 2:36 AM, Stefan Bader wrote:
> On 02.05.21 23:00, Tim Gardner wrote:
>> BugLink: https://bugs.launchpad.net/bugs/1921916
>>
>> [Impact]
>>
>> Microsoft has asked to enable CIFS GCM256 encryption support.
>> SF#00307143
>> This looks like a safe enough feature that the manline kernel
>> would benefit from its inclusion. GCM256 is only enabled with
>> module parameters, so the default behavior remains unchanged.
> 
> Being opt-in is a key argument for allowing this into stable releases. 
> With patch #7 this is not easy to tell but I think it more or less 
> appears to be ok (from what I can tell) and I saw no follow-ups, yet.
> 
>>
>> [Test Plan]
>>
>> Microsoft has tested Focal and Groovy mainline kernels with these
>> patch sets. No regression issues were found.
>>
>> [Where problems could occur]
>>
>> Samba servers without GCM256 support may not connect.
> 
> This might be related to this change which I noticed (not saying I think 
> it should be added now but maybe is something that gets asked for once 
> we have the basic support in):
> 
> commit acf96fef46f271642b90aa658ba49e33ae34ddf0
> Author: Steve French <stfrench at microsoft.com>
> Date:   Sat Oct 17 03:54:27 2020 -0500
> 
>      smb3.1.1: do not fail if no encryption required but server doesn't 
> support it
> 

While this is a righteous patch all on it's own, it is unrelated to this 
series in that it impacts _all_ encryption support (or lack thereof). If 
someone complains then I think it should be a separate bug report.

rtg

-----------
Tim Gardner
Canonical, Inc