Re: [PATCH] mm/vmalloc: Sanitize __get_vm_area() arguments

[Sakari Ailus]

Hi Christoph,

On Mon, Apr 06, 2020 at 06:01:55AM -0700, Christoph Hellwig wrote:
> On Fri, Apr 03, 2020 at 06:32:53PM +0200, Peter Zijlstra wrote:
> > 
> > __get_vm_area() is an exported symbol, make sure the callers stay in
> > the expected memory range. When calling this function with memory
> > ranges outside of the VMALLOC range *bad* things can happen.
> > 
> > (I noticed this when I managed to corrupt the kernel text by accident)
> 
> Maybe it is time to unexport it?  There are only two users:
> 
>  - staging/media/ipu3 really should be using vmap.  And given that it
>    is a staging driver it really doesn't matter anyway if we break it.

It's not very polite to suggest breaking other people's drivers for such a
small matter, staging or not. That'd be bound to break kernel compilation
for a lot of people, if for nothing else.

Anyway, thanks for cc'ing me. I agree with suggestion and I'll submit a
patch to address it.

-- 
Regards,

Sakari Ailus