Re: [char-misc v4.4.y 2/2] mei: bus: type promotion bug in mei_nfc_if_version()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Sun, Sep 23, 2018 at 05:49:02AM +0000, Winkler, Tomas wrote:
> > 
> > On Tue, Sep 04, 2018 at 01:43:04AM +0300, Tomas Winkler wrote:
> > > From: Dan Carpenter <dan.carpenter@oracle.com>
> > >
> > > commit b40b3e9358fbafff6a4ba0f4b9658f6617146f9c upstream
> > >
> > > We accidentally removed the check for negative returns without
> > > considering the issue of type promotion.
> > > The "if_version_length" variable is type size_t so if __mei_cl_recv()
> > > returns a negative then "bytes_recv" is type promoted to a high
> > > positive value and treated as success.
> > >
> > > Cc: <stable@vger.kernel.org> # 4.4
> > 
> > I also need a version of this patch for 4.18.y, 4.14.y, and 4.9.y before I will
> > consider adding it to 4.4.y, as we do not want anyone to ever get a
> > regression moving to a new kernel.
> 
> Right, I've started from the wrong end. 
> Now I've posted the patches for the rest of the required long running versions.

Thanks for all of these, now queued up.

greg k-h