From patchwork Tue Nov 26 22:02:42 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yann Droneaud X-Patchwork-Id: 3241571 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 6566CC045B for ; Tue, 26 Nov 2013 22:04:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8B30320524 for ; Tue, 26 Nov 2013 22:04:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7955520520 for ; Tue, 26 Nov 2013 22:04:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758440Ab3KZWEl (ORCPT ); Tue, 26 Nov 2013 17:04:41 -0500 Received: from smtpfb2-g21.free.fr ([212.27.42.10]:43422 "EHLO smtpfb2-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758434Ab3KZWEl (ORCPT ); Tue, 26 Nov 2013 17:04:41 -0500 Received: from smtp4-g21.free.fr (smtp4-g21.free.fr [212.27.42.4]) by smtpfb2-g21.free.fr (Postfix) with ESMTP id A2D56D19DD7 for ; Tue, 26 Nov 2013 23:04:37 +0100 (CET) Received: from localhost.localdomain (unknown [IPv6:2a01:e35:2e9f:6ac0:8e70:5aff:fe2f:2d74]) by smtp4-g21.free.fr (Postfix) with ESMTP id 5A4414C8139; Tue, 26 Nov 2013 23:03:55 +0100 (CET) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by localhost.localdomain (8.14.7/8.14.7) with ESMTP id rAQM3rZb021415; Tue, 26 Nov 2013 23:03:53 +0100 Received: (from ydroneaud@localhost) by localhost.localdomain (8.14.7/8.14.7/Submit) id rAQM3rrs021414; Tue, 26 Nov 2013 23:03:53 +0100 From: Yann Droneaud To: Roland Dreier , linux-rdma@vger.kernel.org Cc: Or Gerlitz , Matan Barak , Yann Droneaud Subject: [PATCH for v3.13 4/7] IB/uverbs: check reserved field in extended command header Date: Tue, 26 Nov 2013 23:02:42 +0100 Message-Id: X-Mailer: git-send-email 1.8.4.2 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=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham 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 As noted by Daniel Vetter in its article "Botching up ioctls"[1] "Check *all* unused fields and flags and all the padding for whether it's 0, and reject the ioctl if that's not the case. Otherwise your nice plan for future extensions is going right down the gutters since someone *will* submit an ioctl struct with random stack garbage in the yet unused parts. Which then bakes in the ABI that those fields can never be used for anything else but garbage." It's important to ensure that reserved fields are set to known value, so that it will be possible to use them latter to extend the ABI. The same reasonning apply to comp_mask field present in newer uverbs command: per commit 22878dbc9173, unsupported values in comp_mask are rejected. [1] http://blog.ffwll.ch/2013/11/botching-up-ioctls.html Link: http://marc.info/?i=cover.1385501822.git.ydroneaud@opteya.com Signed-off-by: Yann Droneaud --- drivers/infiniband/core/uverbs_main.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c index 6c4fc6338b26..8652c13f6ea2 100644 --- a/drivers/infiniband/core/uverbs_main.c +++ b/drivers/infiniband/core/uverbs_main.c @@ -669,6 +669,9 @@ static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf, if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) return -EINVAL; + if (ex_hdr.cmd_hdr_reserved) + return -EINVAL; + response = (char __user *)(unsigned long)ex_hdr.response; if (response) {