From nobody Sun Sep 7 12:18:20 2025 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 441FFC38145 for ; Fri, 2 Sep 2022 12:34:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236886AbiIBMev (ORCPT ); Fri, 2 Sep 2022 08:34:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52314 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236921AbiIBMdo (ORCPT ); Fri, 2 Sep 2022 08:33:44 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E848FE3420; Fri, 2 Sep 2022 05:28:03 -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 ams.source.kernel.org (Postfix) with ESMTPS id 11954B82AA5; Fri, 2 Sep 2022 12:28:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50655C433C1; Fri, 2 Sep 2022 12:28:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1662121680; bh=MUaU73BWKwBTtGsQu2MymRJAHGJQxN5FzuhKUXGRAns=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k5qEtf2kIx9jDLjEUZGzDYVP5pvLxBoVglI2E8UpxYn4Spvu6f5F1B7vnpo0Mz7ia CrOUjtJeerH4XM/Dv5N5MNUKGIpuhzGmapEaTE9vdLg6DE57F0b82xm+zcpfIFWj+c ssn122FXg9//cTv0n8yi0NrCeRmsIlx4CSEQxV0s= 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 5.4 31/77] net: Fix a data-race around sysctl_net_busy_read. Date: Fri, 2 Sep 2022 14:18:40 +0200 Message-Id: <20220902121404.678101927@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220902121403.569927325@linuxfoundation.org> References: <20220902121403.569927325@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 c84f68bff7f58..a2b12a5cf42bc 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2946,7 +2946,7 @@ void sock_init_data(struct socket *sock, struct sock = *sk) =20 #ifdef CONFIG_NET_RX_BUSY_POLL sk->sk_napi_id =3D 0; - sk->sk_ll_usec =3D sysctl_net_busy_read; + sk->sk_ll_usec =3D READ_ONCE(sysctl_net_busy_read); #endif =20 sk->sk_max_pacing_rate =3D ~0UL; --=20 2.35.1