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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0866CCA47B for ; Mon, 11 Jul 2022 09:45:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233338AbiGKJpX (ORCPT ); Mon, 11 Jul 2022 05:45:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37384 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233413AbiGKJnx (ORCPT ); Mon, 11 Jul 2022 05:43:53 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 019FAA23BE; Mon, 11 Jul 2022 02:21:48 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B4D00B80E7A; Mon, 11 Jul 2022 09:21:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C822C34115; Mon, 11 Jul 2022 09:21:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657531305; bh=6OGDwIFv/5XaLp9/EoSSAjeNh5wIQiQh6P3Zams+wAI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wIBu4DpOJSiDWI998am5HYpqYjlA4XDk0VMU4KjjDupcI8D4x4CFc+5ZDsKWQTnN5 AhnH7TI5JdTOWPYKU/ZChxMyxjXtrJJOYigFKCSb2gOW3oIPK+ko27PG2fpQXpc+sr xzMdV/965qT7HWJjCt2bMwUH+EBan4i1tFXnBxy0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Florian Westphal , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 5.15 058/230] netfilter: nft_payload: dont allow th access for fragments Date: Mon, 11 Jul 2022 11:05:14 +0200 Message-Id: <20220711090605.724516881@linuxfoundation.org> X-Mailer: git-send-email 2.37.0 In-Reply-To: <20220711090604.055883544@linuxfoundation.org> References: <20220711090604.055883544@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: Florian Westphal [ Upstream commit a9e8503def0fd4ed89ade1f61c315f904581d439 ] Loads relative to ->thoff naturally expect that this points to the transport header, but this is only true if pkt->fragoff == 0. This has little effect for rulesets with connection tracking/nat because these enable ip defra. For other rulesets this prevents false matches. Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nft_exthdr.c | 2 +- net/netfilter/nft_payload.c | 9 +++++---- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/net/netfilter/nft_exthdr.c b/net/netfilter/nft_exthdr.c index dbe1f2e7dd9e..9e927ab4df15 100644 --- a/net/netfilter/nft_exthdr.c +++ b/net/netfilter/nft_exthdr.c @@ -167,7 +167,7 @@ nft_tcp_header_pointer(const struct nft_pktinfo *pkt, { struct tcphdr *tcph; - if (pkt->tprot != IPPROTO_TCP) + if (pkt->tprot != IPPROTO_TCP || pkt->fragoff) return NULL; tcph = skb_header_pointer(pkt->skb, nft_thoff(pkt), sizeof(*tcph), buffer); diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index ee359a4a60f5..b46e01365bd9 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -84,7 +84,7 @@ static int __nft_payload_inner_offset(struct nft_pktinfo *pkt) { unsigned int thoff = nft_thoff(pkt); - if (!(pkt->flags & NFT_PKTINFO_L4PROTO)) + if (!(pkt->flags & NFT_PKTINFO_L4PROTO) || pkt->fragoff) return -1; switch (pkt->tprot) { @@ -148,7 +148,7 @@ void nft_payload_eval(const struct nft_expr *expr, offset = skb_network_offset(skb); break; case NFT_PAYLOAD_TRANSPORT_HEADER: - if (!(pkt->flags & NFT_PKTINFO_L4PROTO)) + if (!(pkt->flags & NFT_PKTINFO_L4PROTO) || pkt->fragoff) goto err; offset = nft_thoff(pkt); break; @@ -658,7 +658,7 @@ static void nft_payload_set_eval(const struct nft_expr *expr, offset = skb_network_offset(skb); break; case NFT_PAYLOAD_TRANSPORT_HEADER: - if (!(pkt->flags & NFT_PKTINFO_L4PROTO)) + if (!(pkt->flags & NFT_PKTINFO_L4PROTO) || pkt->fragoff) goto err; offset = nft_thoff(pkt); break; @@ -697,7 +697,8 @@ static void nft_payload_set_eval(const struct nft_expr *expr, if (priv->csum_type == NFT_PAYLOAD_CSUM_SCTP && pkt->tprot == IPPROTO_SCTP && skb->ip_summed != CHECKSUM_PARTIAL) { - if (nft_payload_csum_sctp(skb, nft_thoff(pkt))) + if (pkt->fragoff == 0 && + nft_payload_csum_sctp(skb, nft_thoff(pkt))) goto err; } -- 2.35.1