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 1DB3CC00140 for ; Thu, 18 Aug 2022 03:55:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243084AbiHRDzM (ORCPT ); Wed, 17 Aug 2022 23:55:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242986AbiHRDzK (ORCPT ); Wed, 17 Aug 2022 23:55:10 -0400 Received: from smtp-fw-33001.amazon.com (smtp-fw-33001.amazon.com [207.171.190.10]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07EEBA8971 for ; Wed, 17 Aug 2022 20:55:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1660794909; x=1692330909; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=QkBT3InCcPgr3TJ/MADQsKpY17JGgMcbWCggup6nInk=; b=pj3TZ3Y4PGolxL1aj+ZTfJHfUGcvhJWWBoXe6e8Aor82N91GxvbQh4AD /vzftekFDRzyIxxs2mI4ZkYJMlg3qlk+fZBHuwjzdJ1IinsB8T758GIzB F6XzSIba/rOD1JgBsTiytV/bW2h4jRN+NInwo2NjEwtSoCWv9NW9Vi6Nm Y=; X-IronPort-AV: E=Sophos;i="5.93,245,1654560000"; d="scan'208";a="218841321" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-iad-1a-828bd003.us-east-1.amazon.com) ([10.43.8.6]) by smtp-border-fw-33001.sea14.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2022 03:55:08 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan2.iad.amazon.com [10.40.163.34]) by email-inbound-relay-iad-1a-828bd003.us-east-1.amazon.com (Postfix) with ESMTPS id 10ED681255; Thu, 18 Aug 2022 03:55:05 +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 03:55:04 +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 03:55:02 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni CC: Kuniyuki Iwashima , Kuniyuki Iwashima , , Eliezer Tamir Subject: [PATCH v2 net 09/17] net: Fix a data-race around sysctl_net_busy_read. Date: Wed, 17 Aug 2022 20:52:19 -0700 Message-ID: <20220818035227.81567-10-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 sysctl_net_busy_read, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 2d48d67fa8cd ("net: poll/select low latency socket support") Signed-off-by: Kuniyuki Iwashima --- CC: Eliezer Tamir --- net/core/sock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/sock.c b/net/core/sock.c index 95abf4604d88..788c1372663c 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -3367,7 +3367,7 @@ void sock_init_data(struct socket *sock, struct sock *sk) #ifdef CONFIG_NET_RX_BUSY_POLL sk->sk_napi_id = 0; - sk->sk_ll_usec = sysctl_net_busy_read; + sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read); #endif sk->sk_max_pacing_rate = ~0UL; -- 2.30.2