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 C817EC7618A for ; Wed, 15 Mar 2023 12:20:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231800AbjCOMU3 (ORCPT ); Wed, 15 Mar 2023 08:20:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45398 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232097AbjCOMT5 (ORCPT ); Wed, 15 Mar 2023 08:19:57 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C05285B34 for ; Wed, 15 Mar 2023 05:19:46 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 035856174E for ; Wed, 15 Mar 2023 12:19:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15781C433EF; Wed, 15 Mar 2023 12:19:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678882785; bh=7H2fDWFLq7oTkhdwFhaOFYHwYK7ANczf6ioIzfc3GrY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BbNs7dalz3AWq0JoafD90CJlKoG74jp2+vF5fPw7w9GwoLRS6N/EUkbjZflChu4KM PP1Tw73kIiRY9TFCqxJznXVfArKggGXQNdDpj0ALS/a1ZxBQTvU9OwuwWliWmkXXyV e6v+bjJoeWTuVDr/iv1XMo1meUxGq//RLtCg9kr4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Florian Westphal , Pablo Neira Ayuso , Sasha Levin , =?UTF-8?q?Major=20D=C3=A1vid?= Subject: [PATCH 5.4 44/68] netfilter: tproxy: fix deadlock due to missing BH disable Date: Wed, 15 Mar 2023 13:12:38 +0100 Message-Id: <20230315115727.844456760@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230315115726.103942885@linuxfoundation.org> References: <20230315115726.103942885@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Florian Westphal [ Upstream commit 4a02426787bf024dafdb79b362285ee325de3f5e ] The xtables packet traverser performs an unconditional local_bh_disable(), but the nf_tables evaluation loop does not. Functions that are called from either xtables or nftables must assume that they can be called in process context. inet_twsk_deschedule_put() assumes that no softirq interrupt can occur. If tproxy is used from nf_tables its possible that we'll deadlock trying to aquire a lock already held in process context. Add a small helper that takes care of this and use it. Link: https://lore.kernel.org/netfilter-devel/401bd6ed-314a-a196-1cdc-e13c720cc8f2@balasys.hu/ Fixes: 4ed8eb6570a4 ("netfilter: nf_tables: Add native tproxy support") Reported-and-tested-by: Major Dávid Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- include/net/netfilter/nf_tproxy.h | 7 +++++++ net/ipv4/netfilter/nf_tproxy_ipv4.c | 2 +- net/ipv6/netfilter/nf_tproxy_ipv6.c | 2 +- 3 files changed, 9 insertions(+), 2 deletions(-) diff --git a/include/net/netfilter/nf_tproxy.h b/include/net/netfilter/nf_tproxy.h index 82d0e41b76f22..faa108b1ba675 100644 --- a/include/net/netfilter/nf_tproxy.h +++ b/include/net/netfilter/nf_tproxy.h @@ -17,6 +17,13 @@ static inline bool nf_tproxy_sk_is_transparent(struct sock *sk) return false; } +static inline void nf_tproxy_twsk_deschedule_put(struct inet_timewait_sock *tw) +{ + local_bh_disable(); + inet_twsk_deschedule_put(tw); + local_bh_enable(); +} + /* assign a socket to the skb -- consumes sk */ static inline void nf_tproxy_assign_sock(struct sk_buff *skb, struct sock *sk) { diff --git a/net/ipv4/netfilter/nf_tproxy_ipv4.c b/net/ipv4/netfilter/nf_tproxy_ipv4.c index b2bae0b0e42a1..61cb2341f50fe 100644 --- a/net/ipv4/netfilter/nf_tproxy_ipv4.c +++ b/net/ipv4/netfilter/nf_tproxy_ipv4.c @@ -38,7 +38,7 @@ nf_tproxy_handle_time_wait4(struct net *net, struct sk_buff *skb, hp->source, lport ? lport : hp->dest, skb->dev, NF_TPROXY_LOOKUP_LISTENER); if (sk2) { - inet_twsk_deschedule_put(inet_twsk(sk)); + nf_tproxy_twsk_deschedule_put(inet_twsk(sk)); sk = sk2; } } diff --git a/net/ipv6/netfilter/nf_tproxy_ipv6.c b/net/ipv6/netfilter/nf_tproxy_ipv6.c index 34d51cd426b0c..00761924f2766 100644 --- a/net/ipv6/netfilter/nf_tproxy_ipv6.c +++ b/net/ipv6/netfilter/nf_tproxy_ipv6.c @@ -63,7 +63,7 @@ nf_tproxy_handle_time_wait6(struct sk_buff *skb, int tproto, int thoff, lport ? lport : hp->dest, skb->dev, NF_TPROXY_LOOKUP_LISTENER); if (sk2) { - inet_twsk_deschedule_put(inet_twsk(sk)); + nf_tproxy_twsk_deschedule_put(inet_twsk(sk)); sk = sk2; } } -- 2.39.2