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 77EDD3EFD22; Wed, 20 May 2026 17:00:11 +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=1779296412; cv=none; b=D9cWV2JAHOZoiQN/LFkT+7FbCBuj6U5mHfaRPwPO4A+wmEJED/9oR6EFfXS1Z6G6u9W/M64ffMSnOv0qa5sVaLef5rdeIcTcfnqXWRQvD1KRa8Mig6VVegYRc1e3J9bHjpca0oEDh0pYX/1AfmI4v8mnCXWU/OjeXW4g1HP6wMs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779296412; c=relaxed/simple; bh=fk3lzRXpNfkz+IgBOPS9hfJ3IQWQnLrcg5i+PTB0ixI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sWexQH4gzy3+vFsZNVgPhZN3bsmBE0XvJh7svaTGsLqemU7Wero1jK7nposqb7NkySkHJ3hWdle2U3KzeMkVN64mV+t6lwoRoKr80wJPrhOm9gtl1E0Wu9PvfKZrXMgDY5VPLEFvhjcScANi2yn52ABzl9tXYoHMC9CFgUA253Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=piX8r96x; 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="piX8r96x" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DDD081F000E9; Wed, 20 May 2026 17:00:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779296411; bh=sDtqvqKkgm7U3Wp8LiaET7FFq1XfQKcYhW9cvn5HUjQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=piX8r96xN8OC1+xlpbbHQejkBcekdi3qlg1ova3NjkPhg2vFWjTcGxYql3rsX2TRc 08q054+TZ4u8fn+8PGZkpehWIkCpac3MbEl6Ev854HUCUiMOH/q8kl6mXW1bu3c4Nc PRgovZ919f+KvtuOLbhgc4YXIcBkY0WR0v1X4OAY= 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 7.0 0790/1146] tcp: annotate data-races around tp->srtt_us Date: Wed, 20 May 2026 18:17:20 +0200 Message-ID: <20260520162206.103601353@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162148.390695140@linuxfoundation.org> References: <20260520162148.390695140@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 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 290b693ce7c9d48588d88b15a782a3efc6fa036b ] tcp_get_timestamping_opt_stats() intentionally runs lockless, we must add READ_ONCE() and WRITE_ONCE() annotations to keep KCSAN happy. Fixes: e8bd8fca6773 ("tcp: add SRTT to SCM_TIMESTAMPING_OPT_STATS") Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20260416200319.3608680-12-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 5 +++-- net/ipv4/tcp_input.c | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 80274554eaa12..566a04088fdc5 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3656,7 +3656,8 @@ static void tcp_enable_tx_delay(struct sock *sk, int val) if (delta && sk->sk_state == TCP_ESTABLISHED) { s64 srtt = (s64)tp->srtt_us + delta; - tp->srtt_us = clamp_t(s64, srtt, 1, ~0U); + WRITE_ONCE(tp->srtt_us, + clamp_t(s64, srtt, 1, ~0U)); /* Note: does not deal with non zero icsk_backoff */ tcp_set_rto(sk); @@ -4501,7 +4502,7 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk, READ_ONCE(tp->bytes_retrans), TCP_NLA_PAD); nla_put_u32(stats, TCP_NLA_DSACK_DUPS, READ_ONCE(tp->dsack_dups)); nla_put_u32(stats, TCP_NLA_REORD_SEEN, READ_ONCE(tp->reord_seen)); - nla_put_u32(stats, TCP_NLA_SRTT, tp->srtt_us >> 3); + nla_put_u32(stats, TCP_NLA_SRTT, READ_ONCE(tp->srtt_us) >> 3); nla_put_u16(stats, TCP_NLA_TIMEOUT_REHASH, tp->timeout_rehash); nla_put_u32(stats, TCP_NLA_BYTES_NOTSENT, max_t(int, 0, tp->write_seq - tp->snd_nxt)); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index eee460d19e254..c6c55c51a6409 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1133,7 +1133,7 @@ static void tcp_rtt_estimator(struct sock *sk, long mrtt_us) tcp_bpf_rtt(sk, mrtt_us, srtt); } - tp->srtt_us = max(1U, srtt); + WRITE_ONCE(tp->srtt_us, max(1U, srtt)); } void tcp_update_pacing_rate(struct sock *sk) -- 2.53.0