Re: [RFC PATCH] media: vidtv: fix uaf in vidtv_bridge_on_new_pkts_avail

From: Greg KH

Date: Thu Aug 27 2026 - 01:20:53 EST


On Thu, Aug 27, 2026 at 10:45:08AM +0530, Jeffin Philip wrote:
> On Thu, 27 Aug 2026 06:51:21 +0200, Greg KH wrote:
>
> >While "fun", this is not a normal path that users ever will hit. See
> >this thread where I propose tainting the kernel if you attempt to do
> >this:
> > https://lore.kernel.org/r/20260826-bind_taint-v1-0-52b05f4a965c@xxxxxxxxxxxxxxxxxxx
>
> Thanks for the reference. The task hang is not possible
> then. However, the UAF will be triggered anyway as we are just simulating
> an unbind. Even if the driver's .release is called naturally, if we are
> streaming data, it could cause the UAF, no?

I'm not saying your patch is incorrect, just that using bind/unbind in a
way to justify code changes isn't ok on it's own (we are seeing some
crazy platform and pci driver patches being proposed because of this...)

It's up to the maintainers here, just wanted to point out that this is
NOT a normal codepath that users can ever exercise and think it's not
going to possibly cause problem.

thanks,

greg k-h