From mboxrd@z Thu Jan 1 00:00:00 1970 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 5171DC4332D for ; Mon, 11 Jan 2021 13:08:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13108229C4 for ; Mon, 11 Jan 2021 13:08:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730643AbhAKNIi (ORCPT ); Mon, 11 Jan 2021 08:08:38 -0500 Received: from mail.kernel.org ([198.145.29.99]:54288 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730591AbhAKNHa (ORCPT ); Mon, 11 Jan 2021 08:07:30 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id E35BA22515; Mon, 11 Jan 2021 13:07:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610370435; bh=99pWozPUTAovepm9asQ1gDQbcAldCs2aL9E+joD8nIw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C6YLZ8ntb4toBt+5uw3w7ShaTS1E9WH2uSz2SfWjw0Z9vNV06ulRLrTchJvA1V+nD U0IEixlipWXyB8wG0eaifJjKfbbso6I0u1bSRRcqOmyYoAoPHSjje81C8H8u0YmPHd 1L9VhzmakpTcxvDSQGNTpUx4snuqqLSDVeU2N/Ck= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Petr Machata , Jakub Kicinski Subject: [PATCH 4.19 20/77] net: dcb: Validate netlink message in DCB handler Date: Mon, 11 Jan 2021 14:01:29 +0100 Message-Id: <20210111130037.389318488@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210111130036.414620026@linuxfoundation.org> References: <20210111130036.414620026@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Petr Machata [ Upstream commit 826f328e2b7e8854dd42ea44e6519cd75018e7b1 ] DCB uses the same handler function for both RTM_GETDCB and RTM_SETDCB messages. dcb_doit() bounces RTM_SETDCB mesasges if the user does not have the CAP_NET_ADMIN capability. However, the operation to be performed is not decided from the DCB message type, but from the DCB command. Thus DCB_CMD_*_GET commands are used for reading DCB objects, the corresponding SET and DEL commands are used for manipulation. The assumption is that set-like commands will be sent via an RTM_SETDCB message, and get-like ones via RTM_GETDCB. However, this assumption is not enforced. It is therefore possible to manipulate DCB objects without CAP_NET_ADMIN capability by sending the corresponding command in an RTM_GETDCB message. That is a bug. Fix it by validating the type of the request message against the type used for the response. Fixes: 2f90b8657ec9 ("ixgbe: this patch adds support for DCB to the kernel and ixgbe driver") Signed-off-by: Petr Machata Link: https://lore.kernel.org/r/a2a9b88418f3a58ef211b718f2970128ef9e3793.1608673640.git.me@pmachata.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/dcb/dcbnl.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/dcb/dcbnl.c +++ b/net/dcb/dcbnl.c @@ -1756,6 +1756,8 @@ static int dcb_doit(struct sk_buff *skb, fn = &reply_funcs[dcb->cmd]; if (!fn->cb) return -EOPNOTSUPP; + if (fn->type != nlh->nlmsg_type) + return -EPERM; if (!tb[DCB_ATTR_IFNAME]) return -EINVAL;