Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756339AbaF3Mrk (ORCPT ); Mon, 30 Jun 2014 08:47:40 -0400 Received: from ip4-83-240-18-248.cust.nbox.cz ([83.240.18.248]:53045 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754361AbaF3Mao (ORCPT ); Mon, 30 Jun 2014 08:30:44 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Benjamin LaHaise , Mateusz Guzik , Petr Matousek , Kent Overstreet , Jeff Moyer , Jiri Slaby Subject: [PATCH 3.12 161/181] aio: fix kernel memory disclosure in io_getevents() introduced in v3.10 Date: Mon, 30 Jun 2014 13:53:02 +0200 Message-Id: X-Mailer: git-send-email 2.0.0 In-Reply-To: <61844d8e25eb8899b0836afa9796fa239db80f1f.1404128997.git.jslaby@suse.cz> References: <61844d8e25eb8899b0836afa9796fa239db80f1f.1404128997.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Benjamin LaHaise 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit edfbbf388f293d70bf4b7c0bc38774d05e6f711a upstream. 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. Signed-off-by: Benjamin LaHaise Cc: Mateusz Guzik Cc: Petr Matousek Cc: Kent Overstreet Cc: Jeff Moyer Signed-off-by: Jiri Slaby --- fs/aio.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/aio.c b/fs/aio.c index e609e15f36b9..0abde33de70e 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1066,6 +1066,9 @@ static long aio_read_events_ring(struct kioctx *ctx, head %= ctx->nr_events; tail %= ctx->nr_events; + head %= ctx->nr_events; + tail %= ctx->nr_events; + while (ret < nr) { long avail; struct io_event *ev; -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/