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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 0D9C4C2D0DB for ; Tue, 28 Jan 2020 14:06:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0AF9205F4 for ; Tue, 28 Jan 2020 14:06:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580220365; bh=AdAeuX5VP2SyqUHm1TIqwAL6nRijuMWGMN9OphXvM6k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mRyD169QzKzpagLmOj4Md2CznS9y4VbLOBDTMlAqA3YLFUTFhqgPH6T4+7R4HVmRW 6J8Cye/9P7epnE7UeJmU6md9Zu5eGlwMWMUqnCGgHBTVbXnkcnopx2fyxpdN6FrDz+ sBUI+89qtbl9lC8P7G7qqicczXLJAVmrK8gIEtwU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727830AbgA1OGF (ORCPT ); Tue, 28 Jan 2020 09:06:05 -0500 Received: from mail.kernel.org ([198.145.29.99]:52778 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728234AbgA1OFP (ORCPT ); Tue, 28 Jan 2020 09:05:15 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9CD86205F4; Tue, 28 Jan 2020 14:05:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580220315; bh=AdAeuX5VP2SyqUHm1TIqwAL6nRijuMWGMN9OphXvM6k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=x3jwBmRQoBreWsjVFgmMi8oqUXnqjqWpe/gHzAYLKgXlsiV5HBTR7BnrptQU5hKqQ PfsnhpQyn5OaHsWYdCVP1nmYlMQAHX96tr1B0bMO7sFSOY1jRuENQMkanbqLW7Ieyu mQGSsMl+tOoR1ungB0TJULGZtlx79VZKRmB5aYAs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+156a04714799b1d480bc@syzkaller.appspotmail.com, Pablo Neira Ayuso Subject: [PATCH 5.4 102/104] netfilter: nf_tables: add __nft_chain_type_get() Date: Tue, 28 Jan 2020 15:01:03 +0100 Message-Id: <20200128135831.012305689@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200128135817.238524998@linuxfoundation.org> References: <20200128135817.238524998@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pablo Neira Ayuso commit 826035498ec14b77b62a44f0cb6b94d45530db6f upstream. This new helper function validates that unknown family and chain type coming from userspace do not trigger an out-of-bound array access. Bail out in case __nft_chain_type_get() returns NULL from nft_chain_parse_hook(). Fixes: 9370761c56b6 ("netfilter: nf_tables: convert built-in tables/chains to chain types") Reported-by: syzbot+156a04714799b1d480bc@syzkaller.appspotmail.com Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nf_tables_api.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -489,14 +489,27 @@ static inline u64 nf_tables_alloc_handle static const struct nft_chain_type *chain_type[NFPROTO_NUMPROTO][NFT_CHAIN_T_MAX]; static const struct nft_chain_type * +__nft_chain_type_get(u8 family, enum nft_chain_types type) +{ + if (family >= NFPROTO_NUMPROTO || + type >= NFT_CHAIN_T_MAX) + return NULL; + + return chain_type[family][type]; +} + +static const struct nft_chain_type * __nf_tables_chain_type_lookup(const struct nlattr *nla, u8 family) { + const struct nft_chain_type *type; int i; for (i = 0; i < NFT_CHAIN_T_MAX; i++) { - if (chain_type[family][i] != NULL && - !nla_strcmp(nla, chain_type[family][i]->name)) - return chain_type[family][i]; + type = __nft_chain_type_get(family, i); + if (!type) + continue; + if (!nla_strcmp(nla, type->name)) + return type; } return NULL; } @@ -1095,11 +1108,8 @@ static void nf_tables_table_destroy(stru void nft_register_chain_type(const struct nft_chain_type *ctype) { - if (WARN_ON(ctype->family >= NFPROTO_NUMPROTO)) - return; - nfnl_lock(NFNL_SUBSYS_NFTABLES); - if (WARN_ON(chain_type[ctype->family][ctype->type] != NULL)) { + if (WARN_ON(__nft_chain_type_get(ctype->family, ctype->type))) { nfnl_unlock(NFNL_SUBSYS_NFTABLES); return; } @@ -1551,7 +1561,10 @@ static int nft_chain_parse_hook(struct n hook->num = ntohl(nla_get_be32(ha[NFTA_HOOK_HOOKNUM])); hook->priority = ntohl(nla_get_be32(ha[NFTA_HOOK_PRIORITY])); - type = chain_type[family][NFT_CHAIN_T_DEFAULT]; + type = __nft_chain_type_get(family, NFT_CHAIN_T_DEFAULT); + if (!type) + return -EOPNOTSUPP; + if (nla[NFTA_CHAIN_TYPE]) { type = nf_tables_chain_type_lookup(net, nla[NFTA_CHAIN_TYPE], family, autoload);