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 F334FC00140 for ; Thu, 18 Aug 2022 03:56:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242786AbiHRD4Y (ORCPT ); Wed, 17 Aug 2022 23:56:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240889AbiHRD4W (ORCPT ); Wed, 17 Aug 2022 23:56:22 -0400 Received: from smtp-fw-9103.amazon.com (smtp-fw-9103.amazon.com [207.171.188.200]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 221F6A98F8 for ; Wed, 17 Aug 2022 20:56:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1660794982; x=1692330982; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Mg8N+v1f94NKtfTePka/kejwmYZv37DBXEVyQFBF0go=; b=VVd3SGIL0fvlrgTr3z0MPrSL3et/HWiCwbg+EQCrJE6fSlVPqo26Ouai Axd9OPFIjRngAxVRqPAwf18X1DnNYr03Id2igYP3V/4z6Lzr7+llD2QYf 4MwGv3P3jIY2Kqd7xgF7vOdRPT+/wDedbPYwoc1GlwOLSGkGtOH06gWaw U=; X-IronPort-AV: E=Sophos;i="5.93,245,1654560000"; d="scan'208";a="1045471987" Received: from pdx4-co-svc-p1-lb2-vlan3.amazon.com (HELO email-inbound-relay-iad-1e-b69ea591.us-east-1.amazon.com) ([10.25.36.214]) by smtp-border-fw-9103.sea19.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2022 03:56:21 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan2.iad.amazon.com [10.40.163.34]) by email-inbound-relay-iad-1e-b69ea591.us-east-1.amazon.com (Postfix) with ESMTPS id 48CDFC0D54; Thu, 18 Aug 2022 03:56:20 +0000 (UTC) Received: from EX19D004ANA001.ant.amazon.com (10.37.240.138) by EX13MTAUWB001.ant.amazon.com (10.43.161.207) with Microsoft SMTP Server (TLS) id 15.0.1497.38; Thu, 18 Aug 2022 03:56:18 +0000 Received: from 88665a182662.ant.amazon.com.com (10.43.160.55) by EX19D004ANA001.ant.amazon.com (10.37.240.138) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1118.12; Thu, 18 Aug 2022 03:56:16 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Kuniyuki Iwashima , Kuniyuki Iwashima , , Cong Wang Subject: [PATCH v2 net 14/17] net: Fix data-races around sysctl_devconf_inherit_init_net. Date: Wed, 17 Aug 2022 20:52:24 -0700 Message-ID: <20220818035227.81567-15-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220818035227.81567-1-kuniyu@amazon.com> References: <20220818035227.81567-1-kuniyu@amazon.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.43.160.55] X-ClientProxiedBy: EX13D29UWA002.ant.amazon.com (10.43.160.63) To EX19D004ANA001.ant.amazon.com (10.37.240.138) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org While reading sysctl_devconf_inherit_init_net, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 856c395cfa63 ("net: introduce a knob to control whether to inherit devconf config") Signed-off-by: Kuniyuki Iwashima --- CC: Cong Wang --- net/ipv4/devinet.c | 6 ++++-- net/ipv6/addrconf.c | 2 +- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 92b778e423df..e92428f44f9b 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -2682,8 +2682,10 @@ static __net_init int devinet_init_net(struct net *net) #endif if (!net_eq(net, &init_net)) { + int devconf_inherit_init_net = READ_ONCE(sysctl_devconf_inherit_init_net); + if (IS_ENABLED(CONFIG_SYSCTL) && - sysctl_devconf_inherit_init_net == 3) { + devconf_inherit_init_net == 3) { /* copy from the current netns */ memcpy(all, current->nsproxy->net_ns->ipv4.devconf_all, sizeof(ipv4_devconf)); @@ -2691,7 +2693,7 @@ static __net_init int devinet_init_net(struct net *net) current->nsproxy->net_ns->ipv4.devconf_dflt, sizeof(ipv4_devconf_dflt)); } else if (!IS_ENABLED(CONFIG_SYSCTL) || - sysctl_devconf_inherit_init_net != 2) { + devconf_inherit_init_net != 2) { /* inherit == 0 or 1: copy from init_net */ memcpy(all, init_net.ipv4.devconf_all, sizeof(ipv4_devconf)); diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index b624e3d8c5f0..ac55b02bbe22 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -7164,7 +7164,7 @@ static int __net_init addrconf_init_net(struct net *net) if (IS_ENABLED(CONFIG_SYSCTL) && !net_eq(net, &init_net)) { - switch (sysctl_devconf_inherit_init_net) { + switch (READ_ONCE(sysctl_devconf_inherit_init_net)) { case 1: /* copy from init_net */ memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf)); -- 2.30.2