Re: [PATCH passt 0/5] Add fuzzing

["Richard W.M. Jones" <rjones@redhat.com>]

On Thu, Nov 17, 2022 at 02:58:57PM +0100, Stefano Brivio wrote:
> On Thu, 17 Nov 2022 12:26:09 +0000
> "Richard W.M. Jones" <rjones@redhat.com> wrote:
> 
> > Unfortunately I don't think the --fd option is working.  stracing the
> > code shows the socket being added to the epoll, but it somehow never
> > gets read.  It might be something obvious but I couldn't see what was
> > wrong.  (NB: The socket passed in is *connected* already).
> 
> I'm looking into this (right now just for something obvious, if
> nothing pops up, a bit later) but actually I wonder: couldn't qemu()
> from 5/5 just call socket(AF_UNIX, SOCK_STREAM, 0) and connect() on it?
> Or am I missing something?

We could create a temporary socket in the filesystem.  --fd avoids the
overhead of having to connect on one side and listen/accept on the
other side, and having something in the filesystem which needs to be
cleaned up.  (Linux has the anonymous namespace which avoids cleanup
but not the rest).

> Then sure, as you mentioned, this could be useful for something else,
> so it's probably worth it to get it working.

Right - we have spent a lot of time adding fd passing to qemu, nbdkit
& libnbd just because it's generally useful.

Rich.

-- 
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