Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Tue, 14 Nov 2017 13:17:18 -0800
From: Andy Lutomirski <>
To: Alexander Popov <>
Cc: Mark Rutland <>, Andy Lutomirski <>, 
	"" <>, Kees Cook <>, 
	PaX Team <>, Brad Spengler <>, 
	Ingo Molnar <>, Peter Zijlstra <>, 
	Tycho Andersen <>, Laura Abbott <>, 
	Ard Biesheuvel <>, Borislav Petkov <>, 
	Thomas Gleixner <>, "H . Peter Anvin" <>, X86 ML <>
Subject: Re: [PATCH RFC v5 2/5] gcc-plugins: Add STACKLEAK plugin for tracking
 the kernel stack

On Tue, Nov 14, 2017 at 1:09 PM, Alexander Popov <> wrote:
> Thanks, Mark!
> Please see my comments below.
> On 14.11.2017 19:33, Mark Rutland wrote:
>> On Tue, Nov 14, 2017 at 08:13:43AM -0800, Andy Lutomirski wrote:
>>> What does the STEAKLACK plugin actually do?  I haven't followed this enough.
>> The plugin adds instrumentation to track the maximum stack depth, though only
>> functions with a sufficiently large stackframe are instrumented.
> Yes. Functions with a big stack frame call track_stack() to update the
> lowest_stack value. If CONFIG_VMAP_STACK is disabled, track_stack() is compiled
> with a check for detecting stack depth overflow. This check is what I'm asking
> about.

Then you'll probably have to do something like what I did in the

That being said, I don't entirely see the point.  If you want a
hardened kernel, you're going to enable VMAP_STACK.  Are there really
users of hardened 32-bit kernels?

Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.