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 CAFF0C04A68 for ; Wed, 27 Jul 2022 16:26:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236811AbiG0Q02 (ORCPT ); Wed, 27 Jul 2022 12:26:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51006 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236666AbiG0QY3 (ORCPT ); Wed, 27 Jul 2022 12:24:29 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB9B24E845; Wed, 27 Jul 2022 09:23:23 -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 EE0C6B821BB; Wed, 27 Jul 2022 16:23:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51EA6C433D7; Wed, 27 Jul 2022 16:23:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658939000; bh=r0WuzXOU/MtFRqnw6hVIfAgCFARb/edyBT/qqkSehkg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hnsOVOKhgzuklAxWR8j3f6z6PMA1jhQVOu4TTMEZ3ot9tBFc+bEXdc56LDFO1R15j shnBQrqWgWSwZAupt6rHPERnY+/6V5JTndKzKx+AMy0cabnI9HfCOG9HVQHl+VUGSc HAAMPhmCKbmb3hYF1KNWpScQm5mWREYmAPwfNlyc= 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 4.14 08/37] tcp: Fix a data-race around sysctl_tcp_probe_interval. Date: Wed, 27 Jul 2022 18:10:34 +0200 Message-Id: <20220727161001.198867753@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220727161000.822869853@linuxfoundation.org> References: <20220727161000.822869853@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 2a85388f1d94a9f8b5a529118a2c5eaa0520d85c ] While reading sysctl_tcp_probe_interval, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 05cbc0db03e8 ("ipv4: Create probe timer for tcp PMTU as per RFC4821") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/ipv4/tcp_output.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 8ac23e8439c3..5e9b7dfd9d2d 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2005,7 +2005,7 @@ static inline void tcp_mtu_check_reprobe(struct sock *sk) u32 interval; s32 delta; - interval = net->ipv4.sysctl_tcp_probe_interval; + interval = READ_ONCE(net->ipv4.sysctl_tcp_probe_interval); delta = tcp_jiffies32 - icsk->icsk_mtup.probe_timestamp; if (unlikely(delta >= interval * HZ)) { int mss = tcp_current_mss(sk); -- 2.35.1