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 649D7C32772 for ; Tue, 23 Aug 2022 19:15:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230482AbiHWTPq (ORCPT ); Tue, 23 Aug 2022 15:15:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233022AbiHWTO6 (ORCPT ); Tue, 23 Aug 2022 15:14:58 -0400 Received: from smtp-fw-80007.amazon.com (smtp-fw-80007.amazon.com [99.78.197.218]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7AC8F9F0D4 for ; Tue, 23 Aug 2022 10:52:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1661277142; x=1692813142; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=6twB4CeMTUwa9Ft3vw4/Yav1Jcmh0dSXJXVNECF9zSk=; b=ZrtL4pQGUIP3UDJ45MdGP6ekTZKkRHTlCXfOzB5IAlvZqXl9PL+fUXYh L3pVGsmkfPyPVz9/ucVh0p5XbbOI7KhJda4yVXWHV0bEPhNjqefWFXhLC 5uNgu4IEl4up2XB7U949RMePKsE16j1hNQ+Xi21bkQkHND3QqohtAtiM1 k=; X-IronPort-AV: E=Sophos;i="5.93,258,1654560000"; d="scan'208";a="122631715" Received: from pdx4-co-svc-p1-lb2-vlan3.amazon.com (HELO email-inbound-relay-pdx-2b-31df91b1.us-west-2.amazon.com) ([10.25.36.214]) by smtp-border-fw-80007.pdx80.corp.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Aug 2022 17:51:33 +0000 Received: from EX13MTAUWB001.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan2.pdx.amazon.com [10.236.137.194]) by email-inbound-relay-pdx-2b-31df91b1.us-west-2.amazon.com (Postfix) with ESMTPS id AFC4445202; Tue, 23 Aug 2022 17:51:31 +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; Tue, 23 Aug 2022 17:51:31 +0000 Received: from 88665a182662.ant.amazon.com (10.43.160.160) 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; Tue, 23 Aug 2022 17:51:28 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Kuniyuki Iwashima , Kuniyuki Iwashima , Subject: [PATCH v4 net 13/17] net: Fix data-races around sysctl_fb_tunnels_only_for_init_net. Date: Tue, 23 Aug 2022 10:46:56 -0700 Message-ID: <20220823174700.88411-14-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220823174700.88411-1-kuniyu@amazon.com> References: <20220823174700.88411-1-kuniyu@amazon.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Originating-IP: [10.43.160.160] X-ClientProxiedBy: EX13D07UWA003.ant.amazon.com (10.43.160.35) To EX19D004ANA001.ant.amazon.com (10.37.240.138) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org While reading sysctl_fb_tunnels_only_for_init_net, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 79134e6ce2c9 ("net: do not create fallback tunnels for non-default namespaces") Signed-off-by: Kuniyuki Iwashima --- include/linux/netdevice.h | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 1a3cb93c3dcc..6d3a33fd0cdb 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -640,9 +640,14 @@ extern int sysctl_devconf_inherit_init_net; */ static inline bool net_has_fallback_tunnels(const struct net *net) { - return !IS_ENABLED(CONFIG_SYSCTL) || - !sysctl_fb_tunnels_only_for_init_net || - (net == &init_net && sysctl_fb_tunnels_only_for_init_net == 1); +#if IS_ENABLED(CONFIG_SYSCTL) + int fb_tunnels_only_for_init_net = READ_ONCE(sysctl_fb_tunnels_only_for_init_net); + + return !fb_tunnels_only_for_init_net || + (net_eq(net, &init_net) && fb_tunnels_only_for_init_net == 1); +#else + return true; +#endif } static inline int netdev_queue_numa_node_read(const struct netdev_queue *q) -- 2.30.2