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 EB3E2C001E0 for ; Tue, 25 Jul 2023 11:01:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233583AbjGYLBD (ORCPT ); Tue, 25 Jul 2023 07:01:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233527AbjGYLAk (ORCPT ); Tue, 25 Jul 2023 07:00:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D7822D4E for ; Tue, 25 Jul 2023 03:57:54 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B917D61680 for ; Tue, 25 Jul 2023 10:57:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA713C433C8; Tue, 25 Jul 2023 10:57:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690282673; bh=mJfq2p5ZqmyVjPNRQmQlxmn4cXTm/uV598W1kffiFYY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WGVx0CHAe4R77K+uQi7u4l/bK23xKyh4/+hG+PpNKBl89r5CAirnX0ZuEP3FMsuFH nL4XljEwngBzRJkyS460XRql92pbb86mdDNiWbH12WhTyYDbKLY5SycU3zZy5vtQp9 QS1OB/GejhR/JWzCSnCArPWnY41Sx3MPseug4puU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.4 213/227] tcp: annotate data-races around tp->linger2 Date: Tue, 25 Jul 2023 12:46:20 +0200 Message-ID: <20230725104523.565831972@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104514.821564989@linuxfoundation.org> References: <20230725104514.821564989@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: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit 9df5335ca974e688389c875546e5819778a80d59 ] do_tcp_getsockopt() reads tp->linger2 while another cpu might change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Link: https://lore.kernel.org/r/20230719212857.3943972-8-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 488cf4ae75fab..0ebe775bde688 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3694,11 +3694,11 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname, case TCP_LINGER2: if (val < 0) - tp->linger2 = -1; + WRITE_ONCE(tp->linger2, -1); else if (val > TCP_FIN_TIMEOUT_MAX / HZ) - tp->linger2 = TCP_FIN_TIMEOUT_MAX; + WRITE_ONCE(tp->linger2, TCP_FIN_TIMEOUT_MAX); else - tp->linger2 = val * HZ; + WRITE_ONCE(tp->linger2, val * HZ); break; case TCP_DEFER_ACCEPT: @@ -4106,7 +4106,7 @@ int do_tcp_getsockopt(struct sock *sk, int level, READ_ONCE(net->ipv4.sysctl_tcp_syn_retries); break; case TCP_LINGER2: - val = tp->linger2; + val = READ_ONCE(tp->linger2); if (val >= 0) val = (val ? : READ_ONCE(net->ipv4.sysctl_tcp_fin_timeout)) / HZ; break; -- 2.39.2