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

[Jeff Moyer]

Benjamin LaHaise <bcrl@xxxxxxxxx> 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@xxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/