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Date: Wed, 19 Sep 2012 01:24:05 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: Sjur =?iso-8859-1?Q?Br=E6ndeland?= <sjurbren@gmail.com>,
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        Ohad Ben-Cohen <ohad@wizery.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        virtualization@lists.linux-foundation.org
Subject: Re: [PATCH repost] virtio: don't crash when device is buggy
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On Mon, Sep 17, 2012 at 01:57:17PM +0930, Rusty Russell wrote:
> "Michael S. Tsirkin" <mst@redhat.com> writes:
> 
> > Because of a sanity check in virtio_dev_remove, a buggy device can crash
> > kernel.  And in case of rproc it's userspace so it's not a good idea.
> > We are unloading a driver so how bad can it be?
> > Be less aggressive in handling this error: if it's a driver bug,
> > warning once should be enough.
> >
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> >
> > --
> >
> > 3.6 material?
> 
> I have already applied, this, but it's not for stable, since it's a
> "theoretical bugfix".  That check has been in there forever and noone
> AFAIK has actually struck it.
> 
> Cheers,
> Rusty.

Yes but can't malicious userspace trigger this with remoteproc? If yes
it's not a question of whether anyone has struck it since people don't
normally run malicious userspace :)

-- 
MST