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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 9886CC43603 for ; Wed, 11 Dec 2019 14:20:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 69CF32173E for ; Wed, 11 Dec 2019 14:20:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="h3AF5TZL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729868AbfLKOUe (ORCPT ); Wed, 11 Dec 2019 09:20:34 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:38833 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729858AbfLKOUe (ORCPT ); Wed, 11 Dec 2019 09:20:34 -0500 Received: by mail-pl1-f194.google.com with SMTP id a17so1103775pls.5 for ; Wed, 11 Dec 2019 06:20:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=cW2qhaCWIP/7V8DBuGOvc6Ai8luUyTP8UuFcnaFoYV0=; b=h3AF5TZLcwNBT/uhOK8Rre1vJoz05JQnK/80h1VuJLdol3lHJMDE353QUJYJMpyMyX ismSQOYYRlkdtcFfjU6rfjsqBPrpeCpRL+mui330uCWbRMluEcUZVLE9nTEOoFPs61uH ygFetGaVmA4QpPUPMJ0arRUmjrUTgvaX0+YfDrD5yjHM3Jzneo1qdF0bVVpSS/G+lPm5 PLwlBF7v5Q8w9AoTZAd1dYNPycVgyMv3lk5Jk3YKNkpwE+CCfrqEKbiFToddu1i2panO xSeqyahLCP4tVCP1+tJS/987oF/eNwVQSLxvZG5Qpuz9hyjF4+tpxW8MsryLqx/Bvw9p oE/g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=cW2qhaCWIP/7V8DBuGOvc6Ai8luUyTP8UuFcnaFoYV0=; b=RNtYYM8Ix9JdmTzYMZnU3Uz2Up51C0Oi0GPacTFA/OzyH9DwbyrqqiHEBztKMJb1Km ucuf8Vm+XFv+eeiE9eYkGniNTGYdVa2jKSZtms2qeemt1MhE0FdaZWZ75gaVZd1NAtjx nlNvdE969sjybD+YPAkE2oPvwsjrcm9TGGsITiAsEl2D5hR7i91bVdvfxqOGscjK+DTh pCbxPKAagwOpgKc/tC5a/XisbuIDx2H+j4OhvM6pT4RMZKep9oCMuCu828zAxTMO8txN wsKzqVBcpin05EK81BScolIVsklZqm2B75V1BCge4Dzzr10nHS4C8JPabDuJ2SWDnKoE FbbA== X-Gm-Message-State: APjAAAVBYUOdyHbnp/RpTBRE6Oo+rc6YDVcYwl7jZThHTOzAwODOmKSK bWmalZ89xs6Ku14bGMz2Jrck9pt8KH8= X-Google-Smtp-Source: APXvYqx1NOXeA7I04Xao1v0iMSvyDZ6ohKCsPlWRF6OhXfFQKJD6x9PywcVJV5Nzc3V9MTfr5E5ucA== X-Received: by 2002:a17:902:b187:: with SMTP id s7mr1716066plr.97.1576074033142; Wed, 11 Dec 2019 06:20:33 -0800 (PST) Received: from dhcp-12-139.nay.redhat.com ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id b10sm3533047pff.59.2019.12.11.06.20.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Dec 2019 06:20:32 -0800 (PST) From: Hangbin Liu To: netdev@vger.kernel.org Cc: Jakub Kicinski , Jiri Benc , David Miller , Hangbin Liu Subject: [PATCH net] ipv6/addrconf: only check invalid header values when NETLINK_F_STRICT_CHK is set Date: Wed, 11 Dec 2019 22:20:16 +0800 Message-Id: <20191211142016.13215-1-liuhangbin@gmail.com> X-Mailer: git-send-email 2.19.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In patch 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for doit handlers") we add strict check for inet6_rtm_getaddr(). But we did the invalid header values check before checking if NETLINK_F_STRICT_CHK is set. This may break backwards compatibility if user already set the ifm->ifa_prefixlen, ifm->ifa_flags, ifm->ifa_scope in their netlink code. I didn't move the nlmsg_len check becuase I thought it's a valid check. Reported-by: Jianlin Shi Fixes: 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for doit handlers") Signed-off-by: Hangbin Liu --- net/ipv6/addrconf.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 98d82305d6de..39d861d00377 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -5231,16 +5231,16 @@ static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb, return -EINVAL; } + if (!netlink_strict_get_check(skb)) + return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX, + ifa_ipv6_policy, extack); + ifm = nlmsg_data(nlh); if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) { NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request"); return -EINVAL; } - if (!netlink_strict_get_check(skb)) - return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX, - ifa_ipv6_policy, extack); - err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy, extack); if (err) -- 2.19.2