From nobody Fri Dec 19 19:07:36 2025 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 E6311C00144 for ; Mon, 1 Aug 2022 12:00:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232920AbiHAMAQ (ORCPT ); Mon, 1 Aug 2022 08:00:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33392 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232891AbiHAL66 (ORCPT ); Mon, 1 Aug 2022 07:58:58 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 41BE94A80D; Mon, 1 Aug 2022 04:52:28 -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 9C6BDB81173; Mon, 1 Aug 2022 11:52:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F02C5C43140; Mon, 1 Aug 2022 11:52:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1659354746; bh=/aiidocJnBedxF7hINvURb2iXWFTCt5ZfPgv11oB8As=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SLsQGX2FdKb6UPoJhK4PIuZSc3vR6zaH6oTSMbcvJhuEMY+/QVScaQwvXKXU845hA glaPHgG/p2NLCEvF9T2NE0Sf6n+Nasoxd3prg8DyGWEXntH38AY9w6QdR0wShgQFCp RYsEmoBN329N0IjR2cYUxF4udEzCzEWsrlTBmefY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kuniyuki Iwashima , Wei Wang , "David S. Miller" , Sasha Levin Subject: [PATCH 5.10 39/65] tcp: Fix data-races around sysctl_tcp_reflect_tos. Date: Mon, 1 Aug 2022 13:46:56 +0200 Message-Id: <20220801114135.345687804@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220801114133.641770326@linuxfoundation.org> References: <20220801114133.641770326@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Kuniyuki Iwashima [ Upstream commit 870e3a634b6a6cb1543b359007aca73fe6a03ac5 ] While reading sysctl_tcp_reflect_tos, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: ac8f1710c12b ("tcp: reflect tos value received in SYN to the socket") Signed-off-by: Kuniyuki Iwashima Acked-by: Wei Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/tcp_ipv4.c | 4 ++-- net/ipv6/tcp_ipv6.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index d5f13ff7d900..0d165ce2d80a 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -983,7 +983,7 @@ static int tcp_v4_send_synack(const struct sock *sk, st= ruct dst_entry *dst, if (skb) { __tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr); =20 - tos =3D sock_net(sk)->ipv4.sysctl_tcp_reflect_tos ? + tos =3D READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos) ? (tcp_rsk(req)->syn_tos & ~INET_ECN_MASK) | (inet_sk(sk)->tos & INET_ECN_MASK) : inet_sk(sk)->tos; @@ -1558,7 +1558,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *= sk, struct sk_buff *skb, /* Set ToS of the new socket based upon the value of incoming SYN. * ECT bits are set later in tcp_init_transfer(). */ - if (sock_net(sk)->ipv4.sysctl_tcp_reflect_tos) + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos)) newinet->tos =3D tcp_rsk(req)->syn_tos & ~INET_ECN_MASK; =20 if (!dst) { diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 303b54414a6c..8d91f36cb11b 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -542,7 +542,7 @@ static int tcp_v6_send_synack(const struct sock *sk, st= ruct dst_entry *dst, if (np->repflow && ireq->pktopts) fl6->flowlabel =3D ip6_flowlabel(ipv6_hdr(ireq->pktopts)); =20 - tclass =3D sock_net(sk)->ipv4.sysctl_tcp_reflect_tos ? + tclass =3D READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos) ? (tcp_rsk(req)->syn_tos & ~INET_ECN_MASK) | (np->tclass & INET_ECN_MASK) : np->tclass; @@ -1344,7 +1344,7 @@ static struct sock *tcp_v6_syn_recv_sock(const struct= sock *sk, struct sk_buff * /* Set ToS of the new socket based upon the value of incoming SYN. * ECT bits are set later in tcp_init_transfer(). */ - if (sock_net(sk)->ipv4.sysctl_tcp_reflect_tos) + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos)) newnp->tclass =3D tcp_rsk(req)->syn_tos & ~INET_ECN_MASK; =20 /* Clone native IPv6 options from listening socket (if any) --=20 2.35.1