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 A9F3AECAAD5 for ; Fri, 2 Sep 2022 12:22:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235999AbiIBMWh (ORCPT ); Fri, 2 Sep 2022 08:22:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235915AbiIBMVP (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 C7E4E832D5; Fri, 2 Sep 2022 05:20:58 -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 65A84620E6; Fri, 2 Sep 2022 12:20:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C0F1C433D6; Fri, 2 Sep 2022 12:20:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1662121257; bh=RHODq5FtyWYxRG+5DjCHDRBIpW/miY78MvDSDQSm8U4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ao9gXhHs2RXRb0WGcJWYh+6qy+eSifolUCAZbXDLVom6scRj8ouJfdqvO/kyHy5jr w0Eq00MiKLeRTzou3+li1+gMJmpk5jMYANmL8bvn3zFKElGeIGBymod2pyhCWzepvm S2IhQnDbW238E5aZqrglm7w3KsuFLeHwmATKfV7I= 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 08/31] net: Fix a data-race around sysctl_tstamp_allow_data. Date: Fri, 2 Sep 2022 14:18:34 +0200 Message-Id: <20220902121357.057918976@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 d2154b0afa73c0159b2856f875c6b4fe7cf6a95e ] While reading sysctl_tstamp_allow_data, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: b245be1f4db1 ("net-timestamp: no-payload only sysctl") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/core/skbuff.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 22b216629f9bc..022e26c180241 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3905,7 +3905,7 @@ static bool skb_may_tx_timestamp(struct sock *sk, bool tsonly) { bool ret; - if (likely(sysctl_tstamp_allow_data || tsonly)) + if (likely(READ_ONCE(sysctl_tstamp_allow_data) || tsonly)) return true; read_lock_bh(&sk->sk_callback_lock); -- 2.35.1