From patchwork Tue Jul 12 00:15:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuniyuki Iwashima X-Patchwork-Id: 12914396 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 A71AFC43334 for ; Tue, 12 Jul 2022 00:19:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232137AbiGLATH (ORCPT ); Mon, 11 Jul 2022 20:19:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231686AbiGLASn (ORCPT ); Mon, 11 Jul 2022 20:18:43 -0400 Received: from smtp-fw-6002.amazon.com (smtp-fw-6002.amazon.com [52.95.49.90]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9814F25CA; Mon, 11 Jul 2022 17:17:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1657585075; x=1689121075; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=CRTePnIGj4H8ALoH5op4ZiB9ClWBa861ZK27V5EF1iQ=; b=fpWJli214IGdeYR5zOtVuv5WnDmWDlypDjLctBrGtpyqMg+gl9oyMvp6 P7259xrb+iQjTYJ+alpReLakJK6LXxJ5RekfGDPzbMxeP05L7mpBFpD7Y xSvuKblMms7C+dKv/NxfePnWsZXRMnomjWjaakdvNiW4XGZfMrN9pH+HV E=; X-IronPort-AV: E=Sophos;i="5.92,264,1650931200"; d="scan'208";a="220431228" Received: from iad6-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-pdx-2a-6a4112b2.us-west-2.amazon.com) ([10.124.125.6]) by smtp-border-fw-6002.iad6.amazon.com with ESMTP; 12 Jul 2022 00:17:43 +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-2a-6a4112b2.us-west-2.amazon.com (Postfix) with ESMTPS id 70F584C0053; Tue, 12 Jul 2022 00:17:41 +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 00:17:40 +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 00:17:37 +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 06/15] icmp: Fix a data-race around sysctl_icmp_echo_ignore_broadcasts. Date: Mon, 11 Jul 2022 17:15:24 -0700 Message-ID: <20220712001533.89927-7-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_icmp_echo_ignore_broadcasts, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima --- net/ipv4/icmp.c | 2 +- net/ipv4/sysctl_net_ipv4.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index c406e324c594..4b1d84d3feaa 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -1249,7 +1249,7 @@ int icmp_rcv(struct sk_buff *skb) */ if ((icmph->type == ICMP_ECHO || icmph->type == ICMP_TIMESTAMP) && - net->ipv4.sysctl_icmp_echo_ignore_broadcasts) { + READ_ONCE(net->ipv4.sysctl_icmp_echo_ignore_broadcasts)) { reason = SKB_DROP_REASON_INVALID_PROTO; goto error; } diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index 64682a01914a..cb53476a292e 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -617,6 +617,8 @@ static struct ctl_table ipv4_net_table[] = { .maxlen = sizeof(u8), .mode = 0644, .proc_handler = proc_dou8vec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE }, { .procname = "icmp_ignore_bogus_error_responses",