F23 System Wide Change: Default Local DNS Resolver

[Andrew Lutomirski]

On Tue, Jun 2, 2015 at 2:44 AM, Florian Weimer <fweimer at redhat.com> wrote:
> On 06/01/2015 10:57 PM, Andrew Lutomirski wrote:
>
>> This is glibc we're talking about, though.  Have you tried to get a
>> glibc bug fixed?  It's not a pleasant experience.
>
> It is possible, but it requires effort.  Admittedly, sometimes that
> effort appears disproportionate to what is being fixed.
>
> In this particularly case, only *very* few people are familiar with
> resolv/, and test coverage for that part is extremely poor.
>
>> For example, the bug I reported has a candidate patch.  That patch
>> isn't applied, and the patch looks like the bug might be a security
>> issue.  It's been in that state for months.  This is not unusual for
>> glibc.
>
> Can you explain why you think it is a security issue?

I don't have any very specific reason, but it's a load from an array
with the entirely wrong index, and the code is inscrutable.  I don't
know whether n is attacker-controlled.

As a mitigating factor, it's a load, so it's probably not so terrible.

Regardless, this seems like a bug wrangling failure.  The fix was
committed AFAICT, but no one updated the bug.

--Andy