From patchwork Mon Oct 21 15:14:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Matthieu Baerts (NGI0)" X-Patchwork-Id: 13844311 X-Patchwork-Delegate: matthieu.baerts@tessares.net 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 7D2DA1F9410; Mon, 21 Oct 2024 15:14:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729523675; cv=none; b=r6pjtziY42uTkpUTVhxb+Urbbu4twSC1KDsIfkRonvmkzcDELCQxHJgQZMnE1pT7geQXLpbUHt0rIrtbpCpIzlQhQDrXZJT4IiGcCQXWsgggNmWUYgx83ZoSwy+yLoam5vXmcaoYZr6xVLd36A/52tVlEckGJLtTjobop+XJYwM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729523675; c=relaxed/simple; bh=vWvfcGb12DAvG2TbXrEaAfKBZiWX/4a2tEa1csyld2M=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=LvC7xfvtbXrTQ/Z54YzKTXorle90ncM3ZDz3l9xVLXFhudXh295kSomSSDeCZLvEiLyOJSBe83Cqzc8wfFZbVX4iiEJx2c9klF5LmSWUHa4i97bbm1F4bvUkUFHF7eOGXfQyC76/LbLUQ7TiilBOoUwET0/dAup0CdVCRZdPAy0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QVIj5Nas; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QVIj5Nas" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E231C4CEE9; Mon, 21 Oct 2024 15:14:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729523675; bh=vWvfcGb12DAvG2TbXrEaAfKBZiWX/4a2tEa1csyld2M=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=QVIj5Nas6qg2VuGaA6lYMSp4x7AKP7uCXodmDOLIqWeorU7a9uAEWRuLfpoyzQdyI AtvRwqgfQMmo2swkv0EN/Eh6onC6b3GzPV12lMQV8N3u5LelYgDcDxnFCNvzRfT+u/ fJAQ6AhecnEmgzXA5HOABTxF2EjQfiq2KhDZ5Bb5L28HMHQsHzQVqwOyQlqUqvzFe5 ivHI8aKaHfgHr2fljyFd4rv7nF/Vvmupjl0JR9S69aLhBHakuASwNrFvOfPeoilD7E /Eg3ewf2CfI5Ah9vJ/6n4Gbl625gb4Ss0FG1UYP3iQ/hXVYpuHD8GkBwT9uRKvoMyq nozhB2V+ZR6Ww== From: "Matthieu Baerts (NGI0)" Date: Mon, 21 Oct 2024 17:14:04 +0200 Subject: [PATCH net-next 2/4] mptcp: annotate data-races around subflow->fully_established Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241021-net-next-mptcp-misc-6-13-v1-2-1ef02746504a@kernel.org> References: <20241021-net-next-mptcp-misc-6-13-v1-0-1ef02746504a@kernel.org> In-Reply-To: <20241021-net-next-mptcp-misc-6-13-v1-0-1ef02746504a@kernel.org> To: mptcp@lists.linux.dev, Mat Martineau , Geliang Tang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Matthieu Baerts (NGI0)" , Gang Yan X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=5751; i=matttbe@kernel.org; h=from:subject:message-id; bh=vNuVsHRC0SorCnDtGnHFJS65pDzO9H/fv+K3NOkTUQ8=; b=owEBbQKS/ZANAwAIAfa3gk9CaaBzAcsmYgBnFm/Sd0aZnbkx11rc+2lc/1xp6j6LPLwKct9KL YC+zEHLE9CJAjMEAAEIAB0WIQToy4X3aHcFem4n93r2t4JPQmmgcwUCZxZv0gAKCRD2t4JPQmmg c+N0D/9NpROylZw9WFV8780QF5og6BYKr816P4j+R9/UYOEcwLUCnVrRQkp4NRT0ojQdroqAYuf dGrNepr4/WY/1HOQezTFEDdb7TlUk7/4xAX//YdHPJb4yD80E9IaYFhNTU0Qqzokw5K1ChKhQLY WksOm0O23jEXQjIywIojAZ4j1gPxuO7m674YzHBcMauIjeks72YwyriWRdOFfTvz7tAIu7N8Hzq ZmsevHIJnjp5gX0Zh3icItCnDC5WY3rFoInLX/MUwTpVK08FnTwTiJJCs5yn7ojHcsrGFFc5gGc qsxXJyHPITL7fKO3NXD07rHVy0hnPBgI7DK/7bcbakMpm96w4SrVSwkn6IbLFKdTmWNDrMSjd+P 8akZ+jx3S1kko/AtKhiYU8IIquqJWMfR3BcUB0Gt18KC3/ubFJfM16LXZm/8uklXRE3sCZXb553 zJfGcrtTOD2fApJlddjBg1q0DXZ753Tq6uHFE5h5Zw9WpuaiI7dFLeRf9lkVgqivLV6t1tJQyrH EDDauSWdxdtXNUN14hMutyCLwyCf1aNYm5vsb1hdO646IGgvvHA6FJrQ9yAOkpoG60LyGvCtS5H Y0URh/Kw4ZvlOWiycIykB3bQK8ZJ5SGJW4iRRIdk39R/Y1HfYhFDH2alEqNhi0uRXUYaBEG1Yms YrJbgH3QGq40Jng== X-Developer-Key: i=matttbe@kernel.org; a=openpgp; fpr=E8CB85F76877057A6E27F77AF6B7824F4269A073 From: Gang Yan We introduce the same handling for potential data races with the 'fully_established' flag in subflow as previously done for msk->fully_established. Additionally, we make a crucial change: convert the subflow's 'fully_established' from 'bit_field' to 'bool' type. This is necessary because methods for avoiding data races don't work well with 'bit_field'. Specifically, the 'READ_ONCE' needs to know the size of the variable being accessed, which is not supported in 'bit_field'. Also, 'test_bit' expect the address of 'bit_field'. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/516 Signed-off-by: Gang Yan Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) --- net/mptcp/diag.c | 2 +- net/mptcp/options.c | 4 ++-- net/mptcp/protocol.c | 2 +- net/mptcp/protocol.h | 6 +++--- net/mptcp/subflow.c | 4 ++-- 5 files changed, 9 insertions(+), 9 deletions(-) diff --git a/net/mptcp/diag.c b/net/mptcp/diag.c index 2d3efb405437d85c0bca70d7a92ca3a7363365e1..02205f7994d752cc505991efdf7aa0bbbfd830db 100644 --- a/net/mptcp/diag.c +++ b/net/mptcp/diag.c @@ -47,7 +47,7 @@ static int subflow_get_info(struct sock *sk, struct sk_buff *skb) flags |= MPTCP_SUBFLOW_FLAG_BKUP_REM; if (sf->request_bkup) flags |= MPTCP_SUBFLOW_FLAG_BKUP_LOC; - if (sf->fully_established) + if (READ_ONCE(sf->fully_established)) flags |= MPTCP_SUBFLOW_FLAG_FULLY_ESTABLISHED; if (sf->conn_finished) flags |= MPTCP_SUBFLOW_FLAG_CONNECTED; diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 370c3836b7712f4ca97c99d35a20e88e85a33d70..1603b3702e2207f191fdeef2b29ea2f05fd2b910 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -461,7 +461,7 @@ static bool mptcp_established_options_mp(struct sock *sk, struct sk_buff *skb, return false; /* MPC/MPJ needed only on 3rd ack packet, DATA_FIN and TCP shutdown take precedence */ - if (subflow->fully_established || snd_data_fin_enable || + if (READ_ONCE(subflow->fully_established) || snd_data_fin_enable || subflow->snd_isn != TCP_SKB_CB(skb)->seq || sk->sk_state != TCP_ESTABLISHED) return false; @@ -930,7 +930,7 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, /* here we can process OoO, in-window pkts, only in-sequence 4th ack * will make the subflow fully established */ - if (likely(subflow->fully_established)) { + if (likely(READ_ONCE(subflow->fully_established))) { /* on passive sockets, check for 3rd ack retransmission * note that msk is always set by subflow_syn_recv_sock() * for mp_join subflows diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 1f5c63eb21f0db92341ec941cfe2aec919cdd3de..a6c9661a4c45a00e982d0f68f21621c3cf33469b 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -3511,7 +3511,7 @@ static void schedule_3rdack_retransmission(struct sock *ssk) struct tcp_sock *tp = tcp_sk(ssk); unsigned long timeout; - if (mptcp_subflow_ctx(ssk)->fully_established) + if (READ_ONCE(mptcp_subflow_ctx(ssk)->fully_established)) return; /* reschedule with a timeout above RTT, as we must look only for drop */ diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 568a72702b080d7610425ce5c3a409c7b88da13a..a93e661ef5c435155066ce9cc109092661f0711c 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -513,7 +513,6 @@ struct mptcp_subflow_context { request_bkup : 1, mp_capable : 1, /* remote is MPTCP capable */ mp_join : 1, /* remote is JOINing */ - fully_established : 1, /* path validated */ pm_notified : 1, /* PM hook called for established status */ conn_finished : 1, map_valid : 1, @@ -532,10 +531,11 @@ struct mptcp_subflow_context { is_mptfo : 1, /* subflow is doing TFO */ close_event_done : 1, /* has done the post-closed part */ mpc_drop : 1, /* the MPC option has been dropped in a rtx */ - __unused : 8; + __unused : 9; bool data_avail; bool scheduled; bool pm_listener; /* a listener managed by the kernel PM? */ + bool fully_established; /* path validated */ u32 remote_nonce; u64 thmac; u32 local_nonce; @@ -780,7 +780,7 @@ static inline bool __tcp_can_send(const struct sock *ssk) static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) { /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ - if (subflow->request_join && !subflow->fully_established) + if (subflow->request_join && !READ_ONCE(subflow->fully_established)) return false; return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 6170f2fff71e4f9d64837f2ebf4d81bba224fafb..860903e0642255cf9efb39da9e24c39f6547481f 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -800,7 +800,7 @@ void __mptcp_subflow_fully_established(struct mptcp_sock *msk, const struct mptcp_options_received *mp_opt) { subflow_set_remote_key(msk, subflow, mp_opt); - subflow->fully_established = 1; + WRITE_ONCE(subflow->fully_established, true); WRITE_ONCE(msk->fully_established, true); if (subflow->is_mptfo) @@ -2062,7 +2062,7 @@ static void subflow_ulp_clone(const struct request_sock *req, } else if (subflow_req->mp_join) { new_ctx->ssn_offset = subflow_req->ssn_offset; new_ctx->mp_join = 1; - new_ctx->fully_established = 1; + WRITE_ONCE(new_ctx->fully_established, true); new_ctx->remote_key_valid = 1; new_ctx->backup = subflow_req->backup; new_ctx->request_bkup = subflow_req->request_bkup;