Re: Linux Kernel 5.7.9 DRM Double Free

[Greg KH <greg () kroah com>]

On Wed, Aug 19, 2020 at 06:57:22PM +0200, Greg KH wrote:
> On Wed, Aug 19, 2020 at 05:55:16PM +0200, Greg KH wrote:
> > On Wed, Aug 19, 2020 at 03:42:33PM +0000, zdi-disclosures () trendmicro com wrote:
> > > The specific flaw exists within DRM memory management. The issue results from the lack of validating the 
> > > existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability 
> > > to escalate privileges and execute code in the context of the kernel.
> >
> > Note, this "vulnerability" was only accessible by root, so there's not
> > all that many privileges that could really be escalated there.  Don't
> > know why the original poster did not say that here, as they acknowledged
> > it in the "bug report" they sent many of us.
>
> And to be specific, as I was asked, this was only an issue in the
> nouveau drm driver, not in the DRM "core" at all.  So only that one
> driver was affected.

And to be more specific, as someone else reminded me, you had to enable
fault injection to be able to trip this up as well, something that only
root could do.

thanks,

greg k-h