Re: [PATCH 2/2] aio: fix kernel memory disclosure in io_getevents() introduced in v3.10

[Jeff Moyer <jmoyer@redhat.com>]

Benjamin LaHaise <bcrl@kvack.org> writes:

> On Tue, Jun 24, 2014 at 02:23:20PM -0400, Jeff Moyer wrote:
>> Benjamin LaHaise <bcrl@kvack.org> writes:
>> 
>> > A kernel memory disclosure was introduced in aio_read_events_ring() in v3.10
>> > by commit a31ad380bed817aa25f8830ad23e1a0480fef797.  The changes made to
>> > aio_read_events_ring() failed to correctly limit the index into
>> > ctx->ring_pages[], allowing an attacked to cause the subsequent kmap() of
>> > an arbitrary page with a copy_to_user() to copy the contents into userspace.
>> > This vulnerability has been assigned CVE-2014-0206.  Thanks to Mateusz and
>> > Petr for disclosing this issue.
>> >
>> > This patch applies to v3.12+.  A separate backport is needed for 3.10/3.11.
>> 
>> Note that a 3.10 backport will need to remove this line from free_ioctx
>> as well:
>>                 atomic_sub(avail, &ctx->reqs_active);
>> 
>> Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
>
> Can you post the backport for 3.10 so the -stable folks have something they 
> can use that was tested?  Cheers,

Sure thing.

Cheers,
Jeff