Re: [Bug report] dvbv5-zap crash dvb-tool ARMHF builds

[Mauro Carvalho Chehab <mchehab+samsung@kernel.org>]

Em Thu, 21 Mar 2019 09:41:28 +0000
Sean Young <sean@mess.org> escreveu:

> On Wed, Mar 20, 2019 at 08:38:52PM +0100, Gregor Jasny wrote:
> > Hello Mauro,
> > 
> > On 19.03.19 20:45, Mauro Carvalho Chehab wrote:
> > > Hi Gregor,
> > > 
> > > Samuel reported in priv that the issues he had with user after free were
> > > solved by the patchsets merged at 1.12 and 1.16 stable branches.
> > > 
> > > Could you please generate a new staging release for them?
> > 
> > Sure, I can create a new 1.12 and 1.16 stable release. But when reviewing
> > the patches for approval by debian release managers I noticed an additional
> > double-free that Sean addressed with the following patch:
> > 
> > > https://git.linuxtv.org/v4l-utils.git/commit/?id=ebd890019ba7383b8b486d829f6683c8f49fdbda
> > 
> > Could you please give that patch a thorough review, some testing, and
> > cherry-pick it to stable-1.12 and -1.16 as well?
> 
> I did test it myself (and also under valgrind). The bad paths are hard
> to hit though. I'd say just go ahead with merging and releasing, the patch
> isn't that controversial (I hope!).

I went ahead and cherry-picked the relevant patches to -1.12, -1.14 and
-1.16, and tested both dvbv5-zap and dvbv5-scan with all versions. So, we can
release a new minor version for all those stable branches.

After the patches, on my tests, I didn't get any memory leaks or
double-free issues.

It should be noticed that I had to add a new patch at -1.14, due to
the usage of minor() and major() macros, as one of the files there
were not including sys/sysmacros.h. Without that, I was getting
compilation errors.

Funny enough, this header was already included on two other places
within -1.14.

As the major() and minor() macros were added at glibc 2.3.3[1], released
in 2004 [2], it should be save to include sys/sysmacros.h
unconditionally at stable-1.14.

[1] according with "man 3 makedev", as pointed by:
https://stackoverflow.com/questions/22240973/major-and-minor-macros-defined-in-sys-sysmacros-h-pulled-in-by-iterator

[2] https://ftp.gnu.org/gnu/libc/'s glibc tarball is from 2004-08-03.

Thanks,
Mauro