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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 75D0FC04AAA for ; Thu, 2 May 2019 14:15:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E6CA206DF for ; Thu, 2 May 2019 14:15:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726451AbfEBOPN (ORCPT ); Thu, 2 May 2019 10:15:13 -0400 Received: from mx2.suse.de ([195.135.220.15]:51400 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726310AbfEBOPM (ORCPT ); Thu, 2 May 2019 10:15:12 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 7C0B0AD8C; Thu, 2 May 2019 14:15:11 +0000 (UTC) Received: by unicorn.suse.cz (Postfix, from userid 1000) id CD0F5E00D0; Thu, 2 May 2019 16:15:10 +0200 (CEST) Message-Id: <5368071b5e287d50cf3a93805746217a2f36ff69.1556806084.git.mkubecek@suse.cz> In-Reply-To: References: From: Michal Kubecek Subject: [PATCH net-next v2 1/3] genetlink: do not validate dump requests if there is no policy To: "David S. Miller" Cc: netdev@vger.kernel.org, Johannes Berg , David Ahern , linux-kernel@vger.kernel.org Date: Thu, 2 May 2019 16:15:10 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Unlike do requests, dump genetlink requests now perform strict validation by default even if the genetlink family does not set policy and maxtype because it does validation and parsing on its own (e.g. because it wants to allow different message format for different commands). While the null policy will be ignored, maxtype (which would be zero) is still checked so that any attribute will fail validation. The solution is to only call __nla_validate() from genl_family_rcv_msg() if family->maxtype is set. Fixes: ef6243acb478 ("genetlink: optionally validate strictly/dumps") Signed-off-by: Michal Kubecek Reviewed-by: Johannes Berg --- net/netlink/genetlink.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 72668759cd2b..9814d6dbd2d6 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -537,21 +537,25 @@ static int genl_family_rcv_msg(const struct genl_family *family, return -EOPNOTSUPP; if (!(ops->validate & GENL_DONT_VALIDATE_DUMP)) { - unsigned int validate = NL_VALIDATE_STRICT; int hdrlen = GENL_HDRLEN + family->hdrsize; - if (ops->validate & GENL_DONT_VALIDATE_DUMP_STRICT) - validate = NL_VALIDATE_LIBERAL; - if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) return -EINVAL; - rc = __nla_validate(nlmsg_attrdata(nlh, hdrlen), - nlmsg_attrlen(nlh, hdrlen), - family->maxattr, family->policy, - validate, extack); - if (rc) - return rc; + if (family->maxattr) { + unsigned int validate = NL_VALIDATE_STRICT; + + if (ops->validate & + GENL_DONT_VALIDATE_DUMP_STRICT) + validate = NL_VALIDATE_LIBERAL; + rc = __nla_validate(nlmsg_attrdata(nlh, hdrlen), + nlmsg_attrlen(nlh, hdrlen), + family->maxattr, + family->policy, + validate, extack); + if (rc) + return rc; + } } if (!family->parallel_ops) { -- 2.21.0