From patchwork Tue Mar 22 10:41:01 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 600741 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 3qTqM05FDWz9s9Z; Tue, 22 Mar 2016 21:54:04 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1aiJwn-0008P6-L2; Tue, 22 Mar 2016 10:54:01 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1aiJmN-0003K1-0g for kernel-team@lists.ubuntu.com; Tue, 22 Mar 2016 10:43:15 +0000 Received: from av-217-129-130-179.netvisao.pt ([217.129.130.179] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1aiJmM-0000uR-KQ; Tue, 22 Mar 2016 10:43:14 +0000 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.16.y-ckt 132/142] AIO: properly check iovec sizes Date: Tue, 22 Mar 2016 10:41:01 +0000 Message-Id: <1458643271-4227-133-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1458643271-4227-1-git-send-email-luis.henriques@canonical.com> References: <1458643271-4227-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Cc: Greg Kroah-Hartman , Moritz Muehlenhoff X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.16.7-ckt26 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Greg Kroah-Hartman In Linus's tree, the iovec code has been reworked massively, but in older kernels the AIO layer should be checking this before passing the request on to other layers. Many thanks to Ben Hawkes of Google Project Zero for pointing out the issue. Reported-by: Ben Hawkes Acked-by: Benjamin LaHaise Tested-by: Willy Tarreau Signed-off-by: Greg Kroah-Hartman Cc: Moritz Muehlenhoff Signed-off-by: Luis Henriques --- fs/aio.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index a6f86dae34be..7aaa4164bba5 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1378,11 +1378,16 @@ static ssize_t aio_setup_single_vector(struct kiocb *kiocb, unsigned long *nr_segs, struct iovec *iovec) { - if (unlikely(!access_ok(!rw, buf, kiocb->ki_nbytes))) + size_t len = kiocb->ki_nbytes; + + if (len > MAX_RW_COUNT) + len = MAX_RW_COUNT; + + if (unlikely(!access_ok(!rw, buf, len))) return -EFAULT; iovec->iov_base = buf; - iovec->iov_len = kiocb->ki_nbytes; + iovec->iov_len = len; *nr_segs = 1; return 0; }