From patchwork Sun Mar 15 17:17:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Kubecek X-Patchwork-Id: 222479 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C938C10DCE for ; Sun, 15 Mar 2020 17:17:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4AFA5206E9 for ; Sun, 15 Mar 2020 17:17:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729025AbgCORR4 (ORCPT ); Sun, 15 Mar 2020 13:17:56 -0400 Received: from mx2.suse.de ([195.135.220.15]:56486 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728887AbgCORRz (ORCPT ); Sun, 15 Mar 2020 13:17:55 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id C9F64ADB5; Sun, 15 Mar 2020 17:17:53 +0000 (UTC) Received: by unicorn.suse.cz (Postfix, from userid 1000) id 37E23E0C04; Sun, 15 Mar 2020 18:17:53 +0100 (CET) Message-Id: <40d6e189e3661dc996f7646c848bfb067ac324cb.1584292182.git.mkubecek@suse.cz> In-Reply-To: References: From: Michal Kubecek Subject: [PATCH net 3/3] ethtool: reject unrecognized request flags To: David Miller , Jakub Kicinski , netdev@vger.kernel.org Cc: Johannes Berg , linux-kernel@vger.kernel.org Date: Sun, 15 Mar 2020 18:17:53 +0100 (CET) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org As pointed out by Jakub Kicinski, we ethtool netlink code should respond with an error if request head has flags set which are not recognized by kernel, either as a mistake or because it expects functionality introduced in later kernel versions. To avoid unnecessary roundtrips, use extack cookie to provide the information about supported request flags. Signed-off-by: Michal Kubecek --- net/ethtool/netlink.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c index 180c194fab07..fc9e0b806889 100644 --- a/net/ethtool/netlink.c +++ b/net/ethtool/netlink.c @@ -40,6 +40,7 @@ int ethnl_parse_header(struct ethnl_req_info *req_info, struct nlattr *tb[ETHTOOL_A_HEADER_MAX + 1]; const struct nlattr *devname_attr; struct net_device *dev = NULL; + u32 flags = 0; int ret; if (!header) { @@ -50,8 +51,17 @@ int ethnl_parse_header(struct ethnl_req_info *req_info, ethnl_header_policy, extack); if (ret < 0) return ret; - devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME]; + if (tb[ETHTOOL_A_HEADER_FLAGS]) { + flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]); + if (flags & ~ETHTOOL_FLAG_ALL) { + NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_HEADER_FLAGS], + "unrecognized request flags"); + nl_set_extack_cookie_u32(extack, ETHTOOL_FLAG_ALL); + return -EOPNOTSUPP; + } + } + devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME]; if (tb[ETHTOOL_A_HEADER_DEV_INDEX]) { u32 ifindex = nla_get_u32(tb[ETHTOOL_A_HEADER_DEV_INDEX]); @@ -90,9 +100,7 @@ int ethnl_parse_header(struct ethnl_req_info *req_info, } req_info->dev = dev; - if (tb[ETHTOOL_A_HEADER_FLAGS]) - req_info->flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]); - + req_info->flags = flags; return 0; }