[PATCH RFC] s3: smbd: Consistently map EAs to user namespace

[Daniel Kobras]

Hi all!

Am 27.09.22 um 23:58 schrieb Jeremy Allison:
> On Wed, Sep 28, 2022 at 10:53:19AM +1300, Andrew Bartlett wrote:
(...)
>> We are in agreement.  What I'm saying is that it seems to be a mistake,
>> which can be observed externally, to have mapped other namespaces by
>> simply stripping a prefix.
> 
> Yes ! +1. Exposing other namespaces was the original
> bug. IMHO we should fix for 4.18.0 and announce now
> this change is coming.
> 
> If someone *really* depends on this, we could have
> an option to keep the original behavior.
> 
> But I really don't want to (add that option, that
> is :-).

The original behavior is erratic: initial read of Windows EA 'other.foo'
returns EA 'other.foo' from the filesystem; a write of Windows EA
'other.foo' is redirected to 'user.other.foo' in the filesystem;
subsequent reads of Windows EA 'other.foo' return either 'other.foo' or
'user.other.foo', depending on how the filesystem happens to order its
EAs.

Even if there were someone depending on this, pointing out the bug in
their setup and suggesting to fix it with a specific VFS module that can
perform the mapping in a reliable fashion, seems to be the proper course
of action to me.

Kind regards,

Daniel
-- 
Daniel Kobras
Principal Architect
Puzzle ITC Deutschland
+49 7071 14316 0
www.puzzle-itc.de

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