From patchwork Sun May 4 21:21:14 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yann Droneaud X-Patchwork-Id: 4110811 Return-Path: X-Original-To: patchwork-linux-rdma@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id AA079BFF02 for ; Sun, 4 May 2014 21:22:20 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id CCFEA203F7 for ; Sun, 4 May 2014 21:22:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E26AB201CE for ; Sun, 4 May 2014 21:22:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753866AbaEDVWR (ORCPT ); Sun, 4 May 2014 17:22:17 -0400 Received: from smtpfb1-g21.free.fr ([212.27.42.9]:56828 "EHLO smtpfb1-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753810AbaEDVWR (ORCPT ); Sun, 4 May 2014 17:22:17 -0400 Received: from smtp5-g21.free.fr (smtp5-g21.free.fr [212.27.42.5]) by smtpfb1-g21.free.fr (Postfix) with ESMTP id C6A292D577; Sun, 4 May 2014 23:22:13 +0200 (CEST) Received: from localhost.localdomain (unknown [IPv6:2a01:e35:2e9f:6ac0:cd98:86ba:f22:4471]) by smtp5-g21.free.fr (Postfix) with ESMTP id 3E703D48035; Sun, 4 May 2014 23:20:49 +0200 (CEST) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by localhost.localdomain (8.14.8/8.14.7) with ESMTP id s44LLeTv013257; Sun, 4 May 2014 23:21:40 +0200 Received: (from ydroneaud@localhost) by localhost.localdomain (8.14.8/8.14.8/Submit) id s44LLdOh013256; Sun, 4 May 2014 23:21:39 +0200 From: Yann Droneaud To: Eli Cohen , Roland Dreier Cc: Yann Droneaud , linux-rdma@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH 2/4] RDMA/mlx5: add missing padding at end of struct mlx5_ib_create_srq Date: Sun, 4 May 2014 23:21:14 +0200 Message-Id: <160c8353b2ae45be0eb516c638fe58c74ac9d0cb.1399216475.git.ydroneaud@opteya.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP i386 ABI disagree with most other ABIs regarding alignment of data type larger than 4 bytes: on most ABIs a padding must be added at end of the structures, while it is not required on i386. So for most ABI struct mlx5_ib_create_srq get implicitly padded to be aligned on a 8 bytes multiple, while for i386, such padding is not added. Tool pahole could be used to find such implicit padding: $ pahole --anon_include \ --nested_anon_include \ --recursive \ --class_name mlx5_ib_create_srq \ drivers/infiniband/hw/mlx5/mlx5_ib.o Then, structure layout can be compared between i386 and x86_64: +++ obj-i386/drivers/infiniband/hw/mlx5/mlx5_ib.o.pahole.txt 2014-03-28 11:43:07.386413682 +0100 --- obj-x86_64/drivers/infiniband/hw/mlx5/mlx5_ib.o.pahole.txt 2014-03-27 13:06:17.788472721 +0100 @@ -69,7 +68,6 @@ struct mlx5_ib_create_srq { __u64 db_addr; /* 8 8 */ __u32 flags; /* 16 4 */ - /* size: 20, cachelines: 1, members: 3 */ - /* last cacheline: 20 bytes */ + /* size: 24, cachelines: 1, members: 3 */ + /* padding: 4 */ + /* last cacheline: 24 bytes */ }; ABI disagreement will make an x86_64 kernel try to read past the buffer provided by an i386 binary. When boundary check will be implemented, the x86_64 kernel will refuse to read past the i386 userspace provided buffer and the uverb will fail. Anyway, if the structure lay in memory on a page boundary and next page is not mapped, ib_copy_from_udata() will fail and the uverb will fail. This patch makes create_srq_user() takes care of the input data size to handle the case where no padding was provided. This way, x86_64 kernel will be able to handle struct mlx5_ib_create_srq as sent by unpatched and patched i386 libmlx5. Link: http://marc.info/?i=cover.1399216475.git.ydroneaud@opteya.com Cc: stable@vger.kernel.org Fixes: e126ba97dba9e ('mlx5: Add driver for Mellanox Connect-IB adapter') Signed-off-by: Yann Droneaud --- drivers/infiniband/hw/mlx5/srq.c | 18 +++++++++++++++--- drivers/infiniband/hw/mlx5/user.h | 1 + 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/infiniband/hw/mlx5/srq.c b/drivers/infiniband/hw/mlx5/srq.c index 210b3eaf188a..38ca52181eb6 100644 --- a/drivers/infiniband/hw/mlx5/srq.c +++ b/drivers/infiniband/hw/mlx5/srq.c @@ -35,6 +35,7 @@ #include #include #include +#include #include "mlx5_ib.h" #include "user.h" @@ -84,10 +85,21 @@ static int create_srq_user(struct ib_pd *pd, struct mlx5_ib_srq *srq, int ncont; u32 offset; - if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) { - mlx5_ib_dbg(dev, "failed copy udata\n"); - return -EFAULT; + if (udata->inlen - sizeof(struct ib_uverbs_cmd_hdr) < sizeof(ucmd)) { + if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd) - sizeof(ucmd.reserved))) { + mlx5_ib_dbg(dev, "failed copy udata\n"); + return -EFAULT; + } + } else { + if (ib_copy_from_udata(&ucmd, udata, sizeof(ucmd))) { + mlx5_ib_dbg(dev, "failed copy udata\n"); + return -EFAULT; + } + + if (ucmd.reserved != 0) + return -EINVAL; } + srq->wq_sig = !!(ucmd.flags & MLX5_SRQ_FLAG_SIGNATURE); srq->umem = ib_umem_get(pd->uobject->context, ucmd.buf_addr, buf_size, diff --git a/drivers/infiniband/hw/mlx5/user.h b/drivers/infiniband/hw/mlx5/user.h index d44ecd2c2faf..d0ba264ac1ed 100644 --- a/drivers/infiniband/hw/mlx5/user.h +++ b/drivers/infiniband/hw/mlx5/user.h @@ -110,6 +110,7 @@ struct mlx5_ib_create_srq { __u64 buf_addr; __u64 db_addr; __u32 flags; + __u32 reserved; /* explicit padding (optional on i386) */ }; struct mlx5_ib_create_srq_resp {