From patchwork Fri Jul 15 17:17:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuniyuki Iwashima X-Patchwork-Id: 12919500 X-Patchwork-Delegate: kuba@kernel.org 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 2F9A5C43334 for ; Fri, 15 Jul 2022 17:20:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235576AbiGORUS (ORCPT ); Fri, 15 Jul 2022 13:20:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234994AbiGORUQ (ORCPT ); Fri, 15 Jul 2022 13:20:16 -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 135B6286CA for ; Fri, 15 Jul 2022 10:20:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1657905615; x=1689441615; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=oRpWLG/0a0T6dlbmpF7DIbxw9CBZaBUtouHETSKvZEM=; b=t76Mxt+CEEMSIz0ImvssPnyO9hMM3ZpvCMlW4qAF/pgSGNtfTLQkMggz AYn0O6ztG7eXSSToqWFnQ4dPEEFpEUCTZsyM+pi+c5ya5zK/JGuAFyNbs +EoVl7anHekHrMMuW/Ttdpg/q6cH5x+vaG0MvnYnoAtl6cAHtY8DrwgTG k=; X-IronPort-AV: E=Sophos;i="5.92,274,1650931200"; d="scan'208";a="108935574" Received: from pdx4-co-svc-p1-lb2-vlan3.amazon.com (HELO email-inbound-relay-pdx-2c-d9fba5dd.us-west-2.amazon.com) ([10.25.36.214]) by smtp-border-fw-80007.pdx80.corp.amazon.com with ESMTP; 15 Jul 2022 17:20:15 +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-2c-d9fba5dd.us-west-2.amazon.com (Postfix) with ESMTPS id 84DAF440D1; Fri, 15 Jul 2022 17:20:14 +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 15.0.1497.36; Fri, 15 Jul 2022 17:20:14 +0000 Received: from 88665a182662.ant.amazon.com (10.43.162.124) 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 15.2.1118.9; Fri, 15 Jul 2022 17:20:11 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , David Ahern CC: Kuniyuki Iwashima , Kuniyuki Iwashima , Subject: [PATCH v1 net 08/15] tcp: Fix data-races around sysctl_tcp_migrate_req. Date: Fri, 15 Jul 2022 10:17:48 -0700 Message-ID: <20220715171755.38497-9-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220715171755.38497-1-kuniyu@amazon.com> References: <20220715171755.38497-1-kuniyu@amazon.com> MIME-Version: 1.0 X-Originating-IP: [10.43.162.124] X-ClientProxiedBy: EX13D31UWA003.ant.amazon.com (10.43.160.130) To EX19D004ANA001.ant.amazon.com (10.37.240.138) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org While reading sysctl_tcp_migrate_req, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: f9ac779f881c ("net: Introduce net.ipv4.tcp_migrate_req.") Signed-off-by: Kuniyuki Iwashima --- net/core/sock_reuseport.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c index 3f00a28fe762..5daa1fa54249 100644 --- a/net/core/sock_reuseport.c +++ b/net/core/sock_reuseport.c @@ -387,7 +387,7 @@ void reuseport_stop_listen_sock(struct sock *sk) prog = rcu_dereference_protected(reuse->prog, lockdep_is_held(&reuseport_lock)); - if (sock_net(sk)->ipv4.sysctl_tcp_migrate_req || + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_migrate_req) || (prog && prog->expected_attach_type == BPF_SK_REUSEPORT_SELECT_OR_MIGRATE)) { /* Migration capable, move sk from the listening section * to the closed section. @@ -545,7 +545,7 @@ struct sock *reuseport_migrate_sock(struct sock *sk, hash = migrating_sk->sk_hash; prog = rcu_dereference(reuse->prog); if (!prog || prog->expected_attach_type != BPF_SK_REUSEPORT_SELECT_OR_MIGRATE) { - if (sock_net(sk)->ipv4.sysctl_tcp_migrate_req) + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_migrate_req)) goto select_by_hash; goto failure; }