Re: SOCKET_URING_OP_GETSOCKOPT SOL_SOCKET restriction

[Stefan Metzmacher <metze@samba.org>]

Am 28.03.25 um 16:02 schrieb Stefan Metzmacher:
> Am 28.03.25 um 15:30 schrieb Jens Axboe:
>> On 3/28/25 8:27 AM, Stefan Metzmacher wrote:
>>> Hi Jens,
>>>
>>> while playing with the kernel QUIC driver [1],
>>> I noticed it does a lot of getsockopt() and setsockopt()
>>> calls to sync the required state into and out of the kernel.
>>>
>>> My long term plan is to let the userspace quic handshake logic
>>> work with SOCKET_URING_OP_GETSOCKOPT and SOCKET_URING_OP_SETSOCKOPT.
>>>
>>> The used level is SOL_QUIC and that won't work
>>> as io_uring_cmd_getsockopt() has a restriction to
>>> SOL_SOCKET, while there's no restriction in
>>> io_uring_cmd_setsockopt().
>>>
>>> What's the reason to have that restriction?
>>> And why is it only for the get path and not
>>> the set path?
>>
>> There's absolutely no reason for that, looks like a pure oversight?!
> 
> It seems RFC had the limitation on both:
> https://lore.kernel.org/io-uring/20230724142237.358769-1-leitao@debian.org/
> 
> v0 had it only for get because of some userpointer restrictions:
> https://lore.kernel.org/io-uring/20230724142237.358769-1-leitao@debian.org/
> 
> The merged v7 also talks about the restriction:
> https://lore.kernel.org/all/20231016134750.1381153-1-leitao@debian.org/
> 
> Adding Breno ...
> 
> It seems proto_ops->getsockopt is the problem as it's not changed
> to sockptr_t yet.

commit a7b75c5a8c41445f33efb663887ff5f5c3b4454b
Author: Christoph Hellwig <hch@lst.de>
Date:   Thu Jul 23 08:09:07 2020 +0200

     net: pass a sockptr_t into ->setsockopt

     Rework the remaining setsockopt code to pass a sockptr_t instead of a
     plain user pointer.  This removes the last remaining set_fs(KERNEL_DS)
     outside of architecture specific code.

     Signed-off-by: Christoph Hellwig <hch@lst.de>
     Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
     Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
     Signed-off-by: David S. Miller <davem@davemloft.net>

only converted setsockopt function pointer...

Is there any reason not to change getsockopt too?
Except for someone needs to do the work?

metze