Re: [PATCH v4 00/17] khwasan: kernel hardware assisted address sanitizer

From: Dan Carpenter
Date: Fri Jun 29 2018 - 09:45:18 EST


On Fri, Jun 29, 2018 at 01:26:14PM +0200, Luc Van Oostenryck wrote:
> On Fri, Jun 29, 2018 at 12:04:22PM +0100, Dave Martin wrote:
> >
> > Can sparse be hacked to identify pointer subtractions where the pointers
> > are cannot be statically proved to point into the same allocation?
>
> sparse only see the (deatils of) the function it analyses and all
> visible declarations, nothing more.
>
> It would be more a job for smatch which do global analysis.
> But to identify such subtractions yu must already have a (good)
> pointer alias analysis which I don't think smatch do (but I can
> be wrong, Dan & smatch's ml added in CC).

That would be hard to manage. Maybe in a year from now...

Pointer math errors tend to get caught pretty quick because they're on
the success path so I don't imagine there are huge numbers of bugs.

regards,
dan carpenter