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Date: Tue, 19 Jun 2018 08:19:03 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
Message-ID: <20180619061903.pmiy36kznlkpmanq@sirius.home.kraxel.org>
References: <20180618161729.334-1-marcandre.lureau@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v3 09/26] HACK: vhost-user-backend: allow
 to specify binary to execute
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To: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org, berrange@redhat.com

On Mon, Jun 18, 2018 at 06:17:12PM +0200, Marc-Andr=E9 Lureau wrote:
> An executable with its arguments may be given as 'cmd' property, ex:
> -object vhost-user-backend,id=3Dvui,cmd=3D"./vhost-user-input
> /dev/input..". The executable is then spawn and, by convention, the
> vhost-user socket is passed as fd=3D3. It may be considered a security
> breach to allow creating processes that may execute arbitrary
> executables, so this may be restricted to some known executables (via
> signature etc) or directory.

Hmm, maybe let the device which uses vhost-user-backend handle this?

So you use "-device vhost-user-input-pci,device=3D/dev/input/$dev" and
vhost-user-input-pci translates that into ...
=20
  argv =3D { "$dir/vhost-user-input", "-device", "/dev/input/$dev", NULL =
}

... for vhost-user-backend ?

cheers,
  Gerd