Re: [PATCH v3 1/2] net/handshake: Create a NETLINK service for handling handshake requests

[Hannes Reinecke <hare@suse.de>]

On 2/10/23 15:31, Chuck Lever III wrote:
> 
> 
>> On Feb 10, 2023, at 6:41 AM, Paolo Abeni <pabeni@redhat.com> wrote:
>>
>> On Thu, 2023-02-09 at 16:34 +0000, Chuck Lever III wrote:
>>>
[ .. ]
>>> All that said, the single pending list can be replaced easily. It
>>> would be straightforward to move it into struct net, for example.
>>
>> In the end I don't see a operations needing a full list traversal.
>> handshake_nl_msg_accept walk that, but it stops at netns/proto matching
>> which should be ~always /~very soon in the typical use-case. And as you
>> said it should be easy to avoid even that.
>>
>> I think it could be useful limiting the number of pending handshake to
>> some maximum, to avoid problems in pathological/malicious scenarios.
> 
> Defending against DoS is sensible. Maybe having a per-net
> maximum of 5 or 10 pending handshakes? handshake_request() can
> return an error code if a handshake is requested while we're
> over that maximum.
> 
Can we check the source settings? Having more than one handshake in the 
queue coming from the same SRC IP/SRC Port seems a bit pointless, 
doesn't it?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		           Kernel Storage Architect
hare@suse.de			                  +49 911 74053 688
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