Messages in this thread | | | Date | Mon, 11 Nov 2019 12:46:15 +0100 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH] media:usb:cpia2: Properly check framebuffer mmap offsets |
| |
On Sat, Nov 09, 2019 at 12:39:43PM +0100, Hans Verkuil wrote: > Hi Greg, > > On 11/8/19 9:49 PM, Greg Kroah-Hartman wrote: > > On Fri, Nov 08, 2019 at 09:50:36PM +0000, Omer Shalev wrote: > >> The cpai2 driver's mmap implementation wasn't properly check for all > >> possible offset values. Given a huge offset value , the calculation > >> start_offset + size can wrap around to a low value and pass the check > > > > I thought we checked that in the core of the kernel now, to keep all > > drivers from not having to do this type of thing (as they obviously all > > forgot to.) Why is this still needed here as well? > > Where is that checked in the core? I couldn't find anything, but I might > have been looking in the wrong place.
Sorry, took me a while to find it. Look at be83bbf80682 ("mmap: introduce sane default mmap limits") as I think this should handle the problem already.
thanks,
greg k-h
| |