Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030644AbaGCJZh (ORCPT ); Thu, 3 Jul 2014 05:25:37 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:52695 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030595AbaGCJZ2 (ORCPT ); Thu, 3 Jul 2014 05:25:28 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Benjamin LaHaise , Mateusz Guzik , Petr Matousek , Kent Overstreet , Jeff Moyer , Luis Henriques Subject: [PATCH 3.11 195/198] aio: fix kernel memory disclosure in io_getevents() introduced in v3.10 Date: Thu, 3 Jul 2014 10:20:38 +0100 Message-Id: <1404379241-8590-196-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1404379241-8590-1-git-send-email-luis.henriques@canonical.com> References: <1404379241-8590-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.11.10.13 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Benjamin LaHaise 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. [jmoyer@redhat.com: backported to 3.10] Signed-off-by: Benjamin LaHaise Cc: Mateusz Guzik Cc: Petr Matousek Cc: Kent Overstreet Cc: Jeff Moyer Signed-off-by: Luis Henriques --- fs/aio.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/aio.c b/fs/aio.c index 48f02745b876..618021906aa9 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -719,6 +719,8 @@ static long aio_read_events_ring(struct kioctx *ctx, if (head == ctx->tail) goto out; + head %= ctx->nr_events; + while (ret < nr) { long avail; struct io_event *ev; -- 1.9.1 -- 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/