lkml.org 
[lkml]   [2017]   [Sep]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v7 9/9] sparc64: Add support for ADI (Application Data Integrity)
On Tue 2017-09-05 14:44:56, David Miller wrote:
> From: Pavel Machek <pavel@ucw.cz>
> Date: Mon, 4 Sep 2017 18:25:30 +0200
>
> > Will gcc be able to compile code that uses these automatically? That
> > does not sound easy to me. Can libc automatically use this in malloc()
> > to prevent accessing freed data when buffers are overrun?
> >
> > Is this for benefit of JITs?
>
> Anything that can control mappings and the virtual address used to
> access memory can use ADI.
>
> malloc() is of course one such case. It can map memory with ADI
> enabled, and return buffer addresses to malloc() callers with the
> proper virtual address bits set to satisfy the ADI key checks.
>
> And by induction anything using malloc() for it's memory allocation
> gets ADI protection as well.

I see; that's actually quite a nice trick.

I guess it does not protect against stack-based overflows, but should
help against heap-based overflows, so it improves security a bit, too.

Nice, thanks for explanation.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2017-09-07 00:32    [W:0.104 / U:1.180 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site