Re: [PATCH 0/9] tools subsystem refcounter conversions

From: Arnaldo Carvalho de Melo
Date: Wed Feb 22 2017 - 18:25:19 EST


Em Tue, Feb 21, 2017 at 12:39:35PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Tue, Feb 21, 2017 at 05:34:54PM +0200, Elena Reshetova escreveu:
> > Now when new refcount_t type and API are finally merged
> > (see include/linux/refcount.h), the following
> > patches convert various refcounters in the tools susystem from atomic_t
> > to refcount_t. By doing this we prevent intentional or accidental
> > underflows or overflows that can led to use-after-free vulnerabilities.
>
> Thanks for working on this! I was almost going to jump on doing this
> myself!
>
> I'll try and get this merged ASAP.

So, please take a look at my tmp.perf/refcount branch at:

git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git

There are multiple fixes in it to get it to build and test it, so far,
with:

perf top -F 15000 -d 0

while doing kernel builds and tight usleep 1 loops to create lots of
short lived threads with its map_groups, maps, dsos, etc.

Now running some build tests in some 36 containers with assorted distros
and cross compilers.

- Arnaldo