[arch-dev-public] APNG patch in libpng

[Travis Willard]

On Thu, May 1, 2008 at 6:04 AM, Jan de Groot <jan at jgc.homeip.net> wrote:
>
> On Wed, 2008-04-30 at 15:44 -0400, Travis Willard wrote:
>  > Hey guys,
>  >
>  > Recent exploit found in libpng < 1.2.27
>  > (http://bugs.archlinux.org/task/10192#comment27550) is getting a lot
>  > of attention in our forums and bugtrackers, however since the APNG
>  > patch (included for firefox3's sake -
>  > http://bugs.archlinux.org/task/9570) isn't updated for the new libpng
>  > version yet, I'm blocked on updating this.
>  >
>  > If I drop APNG from libpng to ensure we get updates as quick as
>  > possible, this means firefox3 will need to be rebuilt without system
>  > PNG.  If this happens, that means firefox3 will be using a vulnerable
>  > version of the library, but I can react quicker to vulnerabilities
>  > like this in the future.
>  >
>  > I'm not sure what is the best course of action.  Wait until a new APNG
>  > patch is released? Update and force firefox3 to rebuild?
>  >
>  > >From the libpng website: "The pngtest  sample application distributed
>  > with libpng, pngcrush, and certain versions of ImageMagick are known
>  > to be affected, but the bug is otherwise believed to be quite rare." -
>  > if the bug is quite rare, can we put it off?
>  >
>  > Any input?
>
>  I tried to build libpng 1.2.27 with apng patch, this is what I did to
>  get a working package:
>
>  - apply the 1.2.25-apng patch, ignore the reject: the rejected patch
>  adds checks that don't make sense with 1.2.27 as the variables should be
>  NULL anyways.
>  - Generate a new patch out of this, so we have a clean patch against
>  1.2.27
>  - Run the whole libtoolize --force --copy, aclocal, autoconf, automake
>  crap
>  - Run every make command with "ECHO=echo" appended, as libtool 2.2
>  doesn't export this variable anymore (it's lt_ECHO now)
>
>  This resulted in a 1.2.27 package that still works with animated PNGs in
>  firefox 3.0b5.
>
>  OK to commit to testing?

Wow - you're awesome Jan.  Go for it.