[PATCH] vfprint: validate nargs and argument-based offsets

[Carlos O'Donell]

On Mon, Mar 5, 2012 at 1:06 PM, Kees Cook <kees@outflux.net> wrote:
>> A commenter in Red Hat bugzilla proposed different fix:
>>
>> https://bugzilla.redhat.com/show_bug.cgi?id=794766#c8
>>
>>   The easiest fix would have been to restrict "nargs" to NL_ARGMAX.
>>
>>   http://www.opengroup.org/onlinepubs/9699919799/basedefs/limits.h.html#tag_13_23_03_07
>>
>> which has the benefit of avoiding possibly large heap allocation in the
>> bad case.  Kees, have you considered such approach?
>
> I have no problem with this. I opted against it originally since it seemed
> like a needless limit to nargs when other options for handling it existed.
>
> That said, it's a much simpler fix. :) Would anyone else prefer it over
> the current fix?

We should avoid arbitrary limits.

Your fix has a high QoI and solves the problem.

Cheers,
Carlos.