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 DC984C00140 for ; Thu, 18 Aug 2022 03:54:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243005AbiHRDyZ (ORCPT ); Wed, 17 Aug 2022 23:54:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48130 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242765AbiHRDyW (ORCPT ); Wed, 17 Aug 2022 23:54:22 -0400 Received: from smtp-fw-9102.amazon.com (smtp-fw-9102.amazon.com [207.171.184.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25A729F1B6 for ; Wed, 17 Aug 2022 20:54:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1660794861; x=1692330861; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=pmwCB1rtML/9o8e4ui5GvkioOpZG4mwOUDHFknLWzWw=; b=XfwV+qA9ExmTISnVyHwXpDGwT2bEojogB3TP8eoC8Ed1zP+945l0fDoa yiFvT8VOSwQACDr8a+wxlhlDYytX5tQUJmGYZISz3v9Qz86kNfutZXGr3 dzqh5ahL7d0lbn7WrLTFThbOxIk1PiuOLAVThSlhOwnljnYutPaEp1ekC E=; X-IronPort-AV: E=Sophos;i="5.93,245,1654560000"; d="scan'208";a="250092845" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO email-inbound-relay-iad-1e-90d70b14.us-east-1.amazon.com) ([10.25.36.210]) by smtp-border-fw-9102.sea19.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2022 03:54:05 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan3.iad.amazon.com [10.40.163.38]) by email-inbound-relay-iad-1e-90d70b14.us-east-1.amazon.com (Postfix) with ESMTPS id 9F4D9C02CB; Thu, 18 Aug 2022 03:54:03 +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 03:54:02 +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 03:54:00 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Kuniyuki Iwashima , Kuniyuki Iwashima , Subject: [PATCH v2 net 05/17] ratelimit: Fix data-races in ___ratelimit(). Date: Wed, 17 Aug 2022 20:52:15 -0700 Message-ID: <20220818035227.81567-6-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 rs->interval and rs->burst, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima --- lib/ratelimit.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/lib/ratelimit.c b/lib/ratelimit.c index e01a93f46f83..b59a1d3d0cc3 100644 --- a/lib/ratelimit.c +++ b/lib/ratelimit.c @@ -26,10 +26,12 @@ */ int ___ratelimit(struct ratelimit_state *rs, const char *func) { + int interval = READ_ONCE(rs->interval); + int burst = READ_ONCE(rs->burst); unsigned long flags; int ret; - if (!rs->interval) + if (!interval) return 1; /* @@ -44,7 +46,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func) if (!rs->begin) rs->begin = jiffies; - if (time_is_before_jiffies(rs->begin + rs->interval)) { + if (time_is_before_jiffies(rs->begin + interval)) { if (rs->missed) { if (!(rs->flags & RATELIMIT_MSG_ON_RELEASE)) { printk_deferred(KERN_WARNING @@ -56,7 +58,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func) rs->begin = jiffies; rs->printed = 0; } - if (rs->burst && rs->burst > rs->printed) { + if (burst && burst > rs->printed) { rs->printed++; ret = 1; } else { -- 2.30.2