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 D30CEC433EF for ; Sun, 9 Jan 2022 23:17:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237481AbiAIXRW (ORCPT ); Sun, 9 Jan 2022 18:17:22 -0500 Received: from mail.netfilter.org ([217.70.188.207]:42126 "EHLO mail.netfilter.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237477AbiAIXRI (ORCPT ); Sun, 9 Jan 2022 18:17:08 -0500 Received: from localhost.localdomain (unknown [78.30.32.163]) by mail.netfilter.org (Postfix) with ESMTPSA id 86A55607C1; Mon, 10 Jan 2022 00:14:18 +0100 (CET) From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org Subject: [PATCH net-next 31/32] netfilter: nft_payload: cancel register tracking after payload update Date: Mon, 10 Jan 2022 00:16:39 +0100 Message-Id: <20220109231640.104123-32-pablo@netfilter.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220109231640.104123-1-pablo@netfilter.org> References: <20220109231640.104123-1-pablo@netfilter.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The payload expression might mangle the packet, cancel register tracking since any payload data in the registers is stale. Finer grain register tracking cancellation by inspecting the payload base, offset and length on the register is also possible. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_payload.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index f518bf634997..10f422caa76a 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -798,12 +798,33 @@ static int nft_payload_set_dump(struct sk_buff *skb, const struct nft_expr *expr return -1; } +static bool nft_payload_set_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + int i; + + for (i = 0; i < NFT_REG32_NUM; i++) { + if (!track->regs[i].selector) + continue; + + if (track->regs[i].selector->ops != &nft_payload_ops && + track->regs[i].selector->ops != &nft_payload_fast_ops) + continue; + + track->regs[i].selector = NULL; + track->regs[i].bitwise = NULL; + } + + return false; +} + static const struct nft_expr_ops nft_payload_set_ops = { .type = &nft_payload_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_payload_set)), .eval = nft_payload_set_eval, .init = nft_payload_set_init, .dump = nft_payload_set_dump, + .reduce = nft_payload_set_reduce, }; static const struct nft_expr_ops * -- 2.30.2