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 16984C38145 for ; Fri, 2 Sep 2022 12:22:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236108AbiIBMWr (ORCPT ); Fri, 2 Sep 2022 08:22:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235922AbiIBMVP (ORCPT ); Fri, 2 Sep 2022 08:21:15 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F058B9E6A2; Fri, 2 Sep 2022 05:21:04 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8C093620C5; Fri, 2 Sep 2022 12:21:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88058C433D6; Fri, 2 Sep 2022 12:21:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1662121264; bh=YpPCSFJZjYQX+u7yAHu3e5lF3mBjH9JLx9Fx7DDAunA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iZ5Y2bX0WPSpHnGJRJrnyLoQVZr61q5R5ihLyuAxXyMw1H4BwF9YXOuol4g5DyPks S/GOooeUrttlTb3hxGK5UGWauC3dnvDIkSTmMHCc18XpWFl79sKJVgg20V5wVaW/gB KADJjxjZZeq57XQ1pdyQTseEbnEt7SicJIgFzh20= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kuniyuki Iwashima , "David S. Miller" , Sasha Levin Subject: [PATCH 4.9 10/31] net: Fix a data-race around sysctl_net_busy_read. Date: Fri, 2 Sep 2022 14:18:36 +0200 Message-Id: <20220902121357.135932728@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220902121356.732130937@linuxfoundation.org> References: <20220902121356.732130937@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kuniyuki Iwashima [ Upstream commit e59ef36f0795696ab229569c153936bfd068d21c ] 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 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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 1845a37d9f7e1..e4b28c10901ec 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2508,7 +2508,7 @@ 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 = ~0U; -- 2.35.1