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 632BDC04A68 for ; Wed, 27 Jul 2022 17:14:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229844AbiG0ROx (ORCPT ); Wed, 27 Jul 2022 13:14:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48954 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234073AbiG0RNy (ORCPT ); Wed, 27 Jul 2022 13:13:54 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4BD1276963; Wed, 27 Jul 2022 09:42:22 -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 D5BD3B821BA; Wed, 27 Jul 2022 16:42:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3BE25C433C1; Wed, 27 Jul 2022 16:42:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658940138; bh=TLs54fR9ZjrgFajJSrQMbGvCC1KeHOx8HI9w8RnTpT4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1b+dhEhgd3QrfxOkQ1TAnGIwNO45ieCg7/VlJcc6mRi+VDPXNVu8mKaQ5UmMKquk5 TSdDXePBIwxllPQ13BYHtcNmZm22zCgXpoNMUvxCn1hIMB35/E6uKYv8io8CA5HGBa 15gOptq315507pwVtRRoSCJ6S7QjzLAOSSnc9ux0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kuniyuki Iwashima , "David S. Miller" , Sasha Levin Subject: [PATCH 5.15 119/201] ip: Fix data-races around sysctl_ip_prot_sock. Date: Wed, 27 Jul 2022 18:10:23 +0200 Message-Id: <20220727161032.705219293@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220727161026.977588183@linuxfoundation.org> References: <20220727161026.977588183@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: stable@vger.kernel.org From: Kuniyuki Iwashima [ Upstream commit 9b55c20f83369dd54541d9ddbe3a018a8377f451 ] sysctl_ip_prot_sock is accessed concurrently, and there is always a chance of data-race. So, all readers and writers need some basic protection to avoid load/store-tearing. Fixes: 4548b683b781 ("Introduce a sysctl that modifies the value of PROT_SOCK.") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/net/ip.h | 2 +- net/ipv4/sysctl_net_ipv4.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index a0ac57af82dc..8462ced0c21e 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -352,7 +352,7 @@ static inline bool sysctl_dev_name_is_allowed(const char *name) static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port) { - return port < net->ipv4.sysctl_ip_prot_sock; + return port < READ_ONCE(net->ipv4.sysctl_ip_prot_sock); } #else diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index ead5db7e24ea..a36728277e32 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -97,7 +97,7 @@ static int ipv4_local_port_range(struct ctl_table *table, int write, * port limit. */ if ((range[1] < range[0]) || - (range[0] < net->ipv4.sysctl_ip_prot_sock)) + (range[0] < READ_ONCE(net->ipv4.sysctl_ip_prot_sock))) ret = -EINVAL; else set_local_port_range(net, range); @@ -123,7 +123,7 @@ static int ipv4_privileged_ports(struct ctl_table *table, int write, .extra2 = &ip_privileged_port_max, }; - pports = net->ipv4.sysctl_ip_prot_sock; + pports = READ_ONCE(net->ipv4.sysctl_ip_prot_sock); ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); @@ -135,7 +135,7 @@ static int ipv4_privileged_ports(struct ctl_table *table, int write, if (range[0] < pports) ret = -EINVAL; else - net->ipv4.sysctl_ip_prot_sock = pports; + WRITE_ONCE(net->ipv4.sysctl_ip_prot_sock, pports); } return ret; -- 2.35.1