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 3A9411EA8C for ; Wed, 7 Jun 2023 20:40:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A5CB2C433D2; Wed, 7 Jun 2023 20:40:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1686170446; bh=NsrZFUFLvKBKYWIfkiq1Q9cTLVDj36iBv0zSu72ihFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Da6YOEnSTjlI078YV2ScOMyszfnzfcNnOyu94JmvSMM2tuII7ZHrLJ6sS1w7b4mh0 HaX/qZcglKO8G50bsa3m3P/Jgk0GGjw2stmrIxNeH1dWDCp7l6TlcO3gMpTd7qaLxo SaPlRIKAb5o8NojC0YvjAmC9ljX1orR2hxy4pHLk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mat Martineau , Paolo Abeni , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 058/225] mptcp: fix data race around msk->first access Date: Wed, 7 Jun 2023 22:14:11 +0200 Message-ID: <20230607200916.251557726@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230607200913.334991024@linuxfoundation.org> References: <20230607200913.334991024@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: Paolo Abeni [ Upstream commit 1b1b43ee7a208096ecd79e626f2fc90d4a321111 ] The first subflow socket is accessed outside the msk socket lock by mptcp_subflow_fail(), we need to annotate each write access with WRITE_ONCE, but a few spots still lacks it. Fixes: 76a13b315709 ("mptcp: invoke MP_FAIL response when needed") Reviewed-by: Mat Martineau Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/mptcp/protocol.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 6f6b65d3eed1a..f4206001e2fe5 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -111,7 +111,7 @@ static int __mptcp_socket_create(struct mptcp_sock *msk) if (err) return err; - msk->first = ssock->sk; + WRITE_ONCE(msk->first, ssock->sk); WRITE_ONCE(msk->subflow, ssock); subflow = mptcp_subflow_ctx(ssock->sk); list_add(&subflow->node, &msk->conn_list); @@ -2405,7 +2405,7 @@ static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk, sock_put(ssk); if (ssk == msk->first) - msk->first = NULL; + WRITE_ONCE(msk->first, NULL); out: if (ssk == msk->last_snd) @@ -2706,7 +2706,7 @@ static int __mptcp_init_sock(struct sock *sk) WRITE_ONCE(msk->rmem_released, 0); msk->timer_ival = TCP_RTO_MIN; - msk->first = NULL; + WRITE_ONCE(msk->first, NULL); inet_csk(sk)->icsk_sync_mss = mptcp_sync_mss; WRITE_ONCE(msk->csum_enabled, mptcp_is_checksum_enabled(sock_net(sk))); WRITE_ONCE(msk->allow_infinite_fallback, true); -- 2.39.2