From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6782717756 for ; Wed, 9 Aug 2023 11:20:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DAED8C433C8; Wed, 9 Aug 2023 11:20:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1691580058; bh=Bep+K8XuISJoshbNZRdiMFLSSK8fBqtCThsq5emjGgE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s9N5hsgvIcIDdHqTIVzRN2pAxpwzbYcPt3IOiuhUJR9MOXQ0PdQ/WVkdqqaBbImCP R/grZ8vpKR+EYeqrjG8RU/agyfPXGRqIRCR9jgRPUBox8Od2D32vGz+SbKExvpXHQY K4sBFFXcV7W2nQfTIX8BxKabQIEkwxmOBYS2vW5U= 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 4.19 213/323] tcp: annotate data-races around rskq_defer_accept Date: Wed, 9 Aug 2023 12:40:51 +0200 Message-ID: <20230809103707.868005356@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230809103658.104386911@linuxfoundation.org> References: <20230809103658.104386911@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit ae488c74422fb1dcd807c0201804b3b5e8a322a3 ] do_tcp_getsockopt() reads rskq_defer_accept 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/20230719212857.3943972-9-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 4711963413a49..853a33bf8863e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3009,9 +3009,9 @@ static int do_tcp_setsockopt(struct sock *sk, int level, case TCP_DEFER_ACCEPT: /* Translate value in seconds to number of retransmits */ - icsk->icsk_accept_queue.rskq_defer_accept = - secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ, - TCP_RTO_MAX / HZ); + WRITE_ONCE(icsk->icsk_accept_queue.rskq_defer_accept, + secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ, + TCP_RTO_MAX / HZ)); break; case TCP_WINDOW_CLAMP: @@ -3406,8 +3406,9 @@ static int do_tcp_getsockopt(struct sock *sk, int level, val = (val ? : READ_ONCE(net->ipv4.sysctl_tcp_fin_timeout)) / HZ; break; case TCP_DEFER_ACCEPT: - val = retrans_to_secs(icsk->icsk_accept_queue.rskq_defer_accept, - TCP_TIMEOUT_INIT / HZ, TCP_RTO_MAX / HZ); + val = READ_ONCE(icsk->icsk_accept_queue.rskq_defer_accept); + val = retrans_to_secs(val, TCP_TIMEOUT_INIT / HZ, + TCP_RTO_MAX / HZ); break; case TCP_WINDOW_CLAMP: val = tp->window_clamp; -- 2.39.2