From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 2A88A348C55; Wed, 20 May 2026 18:19:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779301158; cv=none; b=WENNXE69Q3FmATbBFcpCT/ELL5v+gXrR7gLj/5wYm6y5yEtysofSDm2OCNHEI2M5SUjAlTSw+djbYUNGqrfjyXbYrFnwm88aVG0NfEcIBHoKBl2x4I2twm/08P1puAgylF1hMpxpXRbm9S9xBibdyvi0VEwtq96Z5PxFYGNaUsY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779301158; c=relaxed/simple; bh=pIMZ4j4pdc1zYrsXvn2vHs0Ob+ZYCgfrToiLBHGI9vg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=g/zWzX2IPt+PJC0oEvoYRA1eGTAsxUXdqTiV/qiNWo5S7FlNJGvB6lyUeJiVcfCunpG2dBURVKY5r6vqKWvPKXsK9mkRsSCOSpHx4iwL30ShL3uNvNDPoC15TdGukBBrWnO2TbpEl7pdg2Fb+Tp9wpzWzvvoqgeO72Bgq3+VtSc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=eRCtjCXc; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="eRCtjCXc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8ED901F000E9; Wed, 20 May 2026 18:19:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779301157; bh=oqZhHYzSgNM40pbhlbznbKY7V0EoK7htHV4Gis9EdE0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=eRCtjCXc8MMIhvAWfQitbQEV2bsooo/8QFvs4sfNXxhAlA6oPVighqS1M7wePGm2l R9unduxsqWb6mG65AD0/wOvFKralOqx5e5VIuUD2etH/gle7tyF9CUmjQGEC1z5ocL 0NX/8cj/VU5e38YBhJQiarw7sDdSG+phE88yBw8I= 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 6.12 449/666] tcp: add data-race annotations around tp->data_segs_out and tp->total_retrans Date: Wed, 20 May 2026 18:21:00 +0200 Message-ID: <20260520162121.003240495@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162111.222830634@linuxfoundation.org> References: <20260520162111.222830634@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 21e92a38cfd891538598ba8f805e0165a820d532 ] tcp_get_timestamping_opt_stats() intentionally runs lockless, we must add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy. Fixes: 7e98102f4897 ("tcp: record pkts sent and retransmistted") Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20260416200319.3608680-3-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 4 ++-- net/ipv4/tcp_output.c | 8 +++++--- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 9c5fc44647831..382c2895ec311 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4276,9 +4276,9 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk, nla_put_u64_64bit(stats, TCP_NLA_SNDBUF_LIMITED, info.tcpi_sndbuf_limited, TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_DATA_SEGS_OUT, - tp->data_segs_out, TCP_NLA_PAD); + READ_ONCE(tp->data_segs_out), TCP_NLA_PAD); nla_put_u64_64bit(stats, TCP_NLA_TOTAL_RETRANS, - tp->total_retrans, TCP_NLA_PAD); + READ_ONCE(tp->total_retrans), TCP_NLA_PAD); rate = READ_ONCE(sk->sk_pacing_rate); rate64 = (rate != ~0UL) ? rate : ~0ULL; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 5e37dc45639db..dbe39ad886821 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1446,7 +1446,8 @@ static int __tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, if (skb->len != tcp_header_size) { tcp_event_data_sent(tp, sk); - tp->data_segs_out += tcp_skb_pcount(skb); + WRITE_ONCE(tp->data_segs_out, + tp->data_segs_out + tcp_skb_pcount(skb)); tp->bytes_sent += skb->len - tcp_header_size; } @@ -3411,7 +3412,7 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs) TCP_ADD_STATS(sock_net(sk), TCP_MIB_RETRANSSEGS, segs); if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN) __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNRETRANS); - tp->total_retrans += segs; + WRITE_ONCE(tp->total_retrans, tp->total_retrans + segs); tp->bytes_retrans += skb->len; /* make sure skb->data is aligned on arches that require it @@ -4433,7 +4434,8 @@ int tcp_rtx_synack(const struct sock *sk, struct request_sock *req) * However in this case, we are dealing with a passive fastopen * socket thus we can change total_retrans value. */ - tcp_sk_rw(sk)->total_retrans++; + WRITE_ONCE(tcp_sk_rw(sk)->total_retrans, + tcp_sk_rw(sk)->total_retrans + 1); } trace_tcp_retransmit_synack(sk, req); } -- 2.53.0