Re: [PATCH v2] misc: fastrpc: restrict user apps from sending kernel RPC messages

From: Greg Kroah-Hartman
Date: Mon Mar 01 2021 - 10:49:52 EST


On Mon, Mar 01, 2021 at 06:34:10PM +0300, Dmitry Baryshkov wrote:
> On Sat, 13 Feb 2021 at 11:25, Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On Fri, Feb 12, 2021 at 10:26:58PM +0300, Dmitry Baryshkov wrote:
> > > Verify that user applications are not using the kernel RPC message
> > > handle to restrict them from directly attaching to guest OS on the
> > > remote subsystem. This is a port of CVE-2019-2308 fix.
> >
> > A port of the fix of what to what?
>
> I'm sorry for the confusion. It is a port of the original
> Qualcomm/CodeAurora fix to the upstream driver.
>
> See https://source.codeaurora.org/quic/la/kernel/msm-4.9/commit/?id=cc2e11eeb988964af72309f71b0fb21c11ed6ca9,

So this is a fix from 2019 that you never submitted upstream causing all
of these kernels to be vulnerable?

Shouldn't the porting process go the other way, upstream first and then
backport? That ensures we don't end up with 2 years old bugs like this
:(

Ugh.

What's going to change in the development process of this code to
prevent this from happening again?

thanks,

greg k-h