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Subject: Re: [PATCH] ksmbd: add default data stream name in
 FILE_STREAM_INFORMATION
To:     Namjae Jeon <linkinjeon@kernel.org>
Cc:     Steve French <smfrench@gmail.com>,
        CIFS <linux-cifs@vger.kernel.org>
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From:   Tom Talpey <tom@talpey.com>
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Date:   Tue, 21 Sep 2021 14:19:02 -0400
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On 9/20/2021 12:34 PM, Namjae Jeon wrote:
> 2021-09-21 1:08 GMT+09:00, Tom Talpey <tom@talpey.com>:
<snip>
>>
>> My concern here is, what's so special about directories? A special file
>> or fifo, a symlink or reparse/junction, etc. Is it appropriate to cons
>> up a ::$DATA for these? What should the size values be, if so?
> Special files in linux(ksmbd share) is showing as regular file on
> windows client.

This brings up an interesting second question. Is that a good thing?

It seems risky, and perhaps wrong, that one can open such a special file 
and read or write it over SMB3. I can see allowing read attributes, etc, 
but certainly not full access. To me, at a minimum the read or write 
should be failed by ksmbd, if not the CREATE itself. ksmbd should not be 
representing these as ordinary files.

Tom.