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 C75C8C00144 for ; Mon, 1 Aug 2022 11:49:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231223AbiHALtW (ORCPT ); Mon, 1 Aug 2022 07:49:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35144 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231628AbiHALsu (ORCPT ); Mon, 1 Aug 2022 07:48:50 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B1D539BAB; Mon, 1 Aug 2022 04:48:30 -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 AF528612CC; Mon, 1 Aug 2022 11:48:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA4B0C433D6; Mon, 1 Aug 2022 11:48:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1659354509; bh=axpzzvTdsutOwnImGl4YdAhWxtYB2QXjeKH3Z5s6gUo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wvDrdXrbiCiHLRYLsVPEFesfi5+8aNx35iomU+eqBsj1Pg/Z1H/dHEGGJECMwb+EB KXLBqgNdMs8C3/Z0zwZwH2FoJBhvp3CAayEX/uW902pJJRwmRwfM+Pg6Q8HoT/dZz/ Mwfu21JaXZMA9fAgfIg72Vd3Moso/Z+GDYWUTv4M= 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 20/34] tcp: Fix a data-race around sysctl_tcp_autocorking. Date: Mon, 1 Aug 2022 13:47:00 +0200 Message-Id: <20220801114128.806783683@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220801114128.025615151@linuxfoundation.org> References: <20220801114128.025615151@linuxfoundation.org> User-Agent: quilt/0.66 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 85225e6f0a76e6745bc841c9f25169c509b573d8 ] While reading sysctl_tcp_autocorking, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: f54b311142a9 ("tcp: auto corking") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 4b31f6e9ec61..0a570d5d0b38 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -697,7 +697,7 @@ static bool tcp_should_autocork(struct sock *sk, struct sk_buff *skb, int size_goal) { return skb->len < size_goal && - sock_net(sk)->ipv4.sysctl_tcp_autocorking && + READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_autocorking) && !tcp_rtx_queue_empty(sk) && refcount_read(&sk->sk_wmem_alloc) > skb->truesize; } -- 2.35.1