From patchwork Tue Jul 12 00:15:32 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuniyuki Iwashima X-Patchwork-Id: 12914405 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 9B21DC433EF for ; Tue, 12 Jul 2022 00:21:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231761AbiGLAVw (ORCPT ); Mon, 11 Jul 2022 20:21:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230143AbiGLAVf (ORCPT ); Mon, 11 Jul 2022 20:21:35 -0400 Received: from smtp-fw-80006.amazon.com (smtp-fw-80006.amazon.com [99.78.197.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 45D9650732; Mon, 11 Jul 2022 17:20:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1657585242; x=1689121242; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=o2IQhksG9u/rLoWbiTge5Bm7QQEq4DXZfmZnzMQ38Jw=; b=dJl2bGJdr7BAQyTxzsHdPkd4Zfncf1hOXF6RAw83uienXtrlT6gzRYG3 wVJgO19kfqAUx8e0QnqAKRKfZiDBbhYvOIPvcdzIM+bqovwaG6wPODIy2 Zesh8ZG6Oj3QRE5FR8UxrLUKo2T70LgNZXd0QhUJE8wf08VoFUR3nh2EO Y=; X-IronPort-AV: E=Sophos;i="5.92,264,1650931200"; d="scan'208";a="107136288" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO email-inbound-relay-pdx-1box-2b-3386f33d.us-west-2.amazon.com) ([10.25.36.210]) by smtp-border-fw-80006.pdx80.corp.amazon.com with ESMTP; 12 Jul 2022 00:20:41 +0000 Received: from EX13MTAUWB001.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan3.pdx.amazon.com [10.236.137.198]) by email-inbound-relay-pdx-1box-2b-3386f33d.us-west-2.amazon.com (Postfix) with ESMTPS id 935018B64C; Tue, 12 Jul 2022 00:20:40 +0000 (UTC) Received: from EX19D004ANA001.ant.amazon.com (10.37.240.138) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1497.36; Tue, 12 Jul 2022 00:20:39 +0000 Received: from 88665a182662.ant.amazon.com.com (10.43.161.185) 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; Tue, 12 Jul 2022 00:20:36 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , David Ahern , Luis Chamberlain , Kees Cook , Iurii Zaikin CC: Kuniyuki Iwashima , Kuniyuki Iwashima , , Subject: [PATCH v1 net 14/15] ipv4: Fix data-races around sysctl_ip_dynaddr. Date: Mon, 11 Jul 2022 17:15:32 -0700 Message-ID: <20220712001533.89927-15-kuniyu@amazon.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220712001533.89927-1-kuniyu@amazon.com> References: <20220712001533.89927-1-kuniyu@amazon.com> MIME-Version: 1.0 X-Originating-IP: [10.43.161.185] X-ClientProxiedBy: EX13D04UWB002.ant.amazon.com (10.43.161.133) 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_ip_dynaddr, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima --- Documentation/networking/ip-sysctl.rst | 2 +- net/ipv4/af_inet.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index 0e58001f8580..b3a534ed0e7c 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -1179,7 +1179,7 @@ ip_autobind_reuse - BOOLEAN option should only be set by experts. Default: 0 -ip_dynaddr - BOOLEAN +ip_dynaddr - INTEGER If set non-zero, enables support for dynamic addresses. If set to a non-zero value larger than 1, a kernel log message will be printed when dynamic address rewriting diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 93da9f783bec..ac67f6b4ec70 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1246,7 +1246,7 @@ static int inet_sk_reselect_saddr(struct sock *sk) if (new_saddr == old_saddr) return 0; - if (sock_net(sk)->ipv4.sysctl_ip_dynaddr > 1) { + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) > 1) { pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n", __func__, &old_saddr, &new_saddr); } @@ -1301,7 +1301,7 @@ int inet_sk_rebuild_header(struct sock *sk) * Other protocols have to map its equivalent state to TCP_SYN_SENT. * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme */ - if (!sock_net(sk)->ipv4.sysctl_ip_dynaddr || + if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) || sk->sk_state != TCP_SYN_SENT || (sk->sk_userlocks & SOCK_BINDADDR_LOCK) || (err = inet_sk_reselect_saddr(sk)) != 0)