Re: [PATCH] nbd: restrict sockets to TCP and UDP
From: Richard W.M. Jones
Date: Tue Nov 18 2025 - 13:16:34 EST
On Tue, Nov 18, 2025 at 06:56:33PM +0100, Pavel Machek wrote:
> Hi!
>
> > Recently, syzbot started to abuse NBD with all kinds of sockets.
> >
> > Commit cf1b2326b734 ("nbd: verify socket is supported during setup")
> > made sure the socket supported a shutdown() method.
> >
> > Explicitely accept TCP and UNIX stream sockets.
>
> Note that running nbd server and client on same machine is not safe in
> read-write mode. It may deadlock under low memory conditions.
>
> Thus I'm not sure if we should accept UNIX sockets.
Both nbd-client and nbdkit have modes where they can mlock themselves
into RAM.
Rich.
--
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