Re: [PATCH] video: hgafb: correctly handle card detect failure during probe

From: Greg Kroah-Hartman
Date: Thu May 20 2021 - 10:00:03 EST


On Thu, May 20, 2021 at 07:10:39PM +0530, Anirudh Rayabharam wrote:
> On Mon, May 17, 2021 at 12:57:14AM +0530, Anirudh Rayabharam wrote:
> > The return value of hga_card_detect() is not properly handled causing
> > the probe to succeed even though hga_card_detect() failed. Since probe
> > succeeds, hgafb_open() can be called which will end up operating on an
> > unmapped hga_vram. This results in an out-of-bounds access as reported
> > by kernel test robot [1].
> >
> > To fix this, correctly detect failure of hga_card_detect() by checking
> > for a non-zero error code.
> >
> > [1]: https://lore.kernel.org/lkml/20210516150019.GB25903@xsang-OptiPlex-9020/
> >
> > Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> > Fixes: dc13cac4862c ("video: hgafb: fix potential NULL pointer dereference")
>
> Greg, this is one of the UMN fixes we did. So, do you want to take this
> patch into your tree?

Yes, will queue it up in a few days after Linus takes the current pull
request I sent him for this.

thanks,

greg k-h