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 2265A33FE15; Sat, 30 May 2026 17:21:08 +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=1780161669; cv=none; b=OSfayMMyTcy1Xfw1CA6j3SRasFKii8FTDnMo4D/oCG8rRNf+FIWlVM60RfRu/9EnZ8leZX7DiYKxKm1l6m9ySgTDGqfASpawVd5jVXz9mLOcGae7anYBFIrpU9GHM4o59ZyBN1BGs4kWCujXmaD3jdKv92u62zIp4jtD5h42Cwo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780161669; c=relaxed/simple; bh=w0w/cG3mVaOTTPYDZNaFnf2nme3X3l0Sm3mPHM/Ab+k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G6bQY6SARzHffrgu/v3vQpdPICKENve8blhVXZ2mvgkOJf5MaRggCbUUdQXRsh4VCiEoqQT08epBaJ41KB5BUx84fgiOTS3Ain5180ImDXR4eFfMMahCcq6FHVWCJ6PwC4wtSJw20OSfyePwaTdAiKtrTsZjjyu3Xlu2mL7fHRg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JvJM0QkR; 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="JvJM0QkR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 631591F00898; Sat, 30 May 2026 17:21:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780161668; bh=8W7kHgzP2gfgsBVFiJysMVsiEo4aaUJBlC3lAPA77w8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=JvJM0QkRkzg2bRStqpn9MHUEjGTDl8ylEJAn8iDhZtxh3jTUgPUm9Z2ssx99JDeDp dHEBTYV/p2QsKnNnDgvgqQTH2/Qbhud693TL2469eKTM2HNwWX6dJxynt6Zjp0P3+/ 7Q7fmdfULT2TJGcmNknVz9j05AXNdxBy4sFYF7n8= 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 6.1 691/969] tcp: annotate data-races around tp->bytes_retrans Date: Sat, 30 May 2026 18:03:35 +0200 Message-ID: <20260530160319.591843509@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160300.485627683@linuxfoundation.org> References: <20260530160300.485627683@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 5efc7b9f7cbd43401f1af81d3d7f2be00f93390d ] tcp_get_timestamping_opt_stats() intentionally runs lockless, we must add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy. Fixes: fb31c9b9f6c8 ("tcp: add data bytes retransmitted stats") Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20260416200319.3608680-9-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 4 ++-- net/ipv4/tcp_output.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index eb59c3d022bb7..c60f8c69c19f5 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4110,8 +4110,8 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk, nla_put_u64_64bit(stats, TCP_NLA_BYTES_SENT, READ_ONCE(tp->bytes_sent), TCP_NLA_PAD); - nla_put_u64_64bit(stats, TCP_NLA_BYTES_RETRANS, tp->bytes_retrans, - TCP_NLA_PAD); + nla_put_u64_64bit(stats, TCP_NLA_BYTES_RETRANS, + READ_ONCE(tp->bytes_retrans), TCP_NLA_PAD); nla_put_u32(stats, TCP_NLA_DSACK_DUPS, tp->dsack_dups); nla_put_u32(stats, TCP_NLA_REORD_SEEN, tp->reord_seen); nla_put_u32(stats, TCP_NLA_SRTT, tp->srtt_us >> 3); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index bb023a07cb1fc..aa2832c90e272 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3289,7 +3289,7 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs) if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN) __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNRETRANS); WRITE_ONCE(tp->total_retrans, tp->total_retrans + segs); - tp->bytes_retrans += skb->len; + WRITE_ONCE(tp->bytes_retrans, tp->bytes_retrans + skb->len); /* make sure skb->data is aligned on arches that require it * and check if ack-trimming & collapsing extended the headroom -- 2.53.0