From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794585899; b=ChotRPy3RX1O1mwJjsgHQGELNaoKkneYY9U3IMOgrRychGmSWM0S7iYeA1kTQ3t/w9pk 9H15Dgk8yNALKfmSN6KA5Yk2wR7lpyWnnqswvW3l/u7eWYDtzZN2ryNbOHzN2CwhFdUDV CZ87h1qKW46WWpq9x//BxQjOxr3eErkvlbPBlZKdqTAC8kwexg8hLbS54ZWtIpkk6RuNm ++BiqyIFy3Hm7XDQ/XAJezy41/C9veR9oIoNgY3zayfFTsIL62vfbLSsjFtNYyo2Nj6Rr 1BiXppYQTiIfHJ7WEIUVcIDA06OS6xKs+awMpnRNtWQd3Nv8FCm9FD1v79A79AMMAhg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794585899; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=I4RDqc99Iemnn+j0KFG9CY/5UMe8CW4PC20keqzeLj4=; b=3FgZ+yqrr6WbLW9TUb3dH2AKJ2y27q8h5d3SqocQAs2AKOv4cdxkgSCPT8E+Vw9Ca/VJ 33VTzjtLnLbjY/OowP8OjGIKQSI8UnkpVqwF+AQQUn9hDJMCeQNzlQ39ZBE+NguXJuiV8 Q8uOqO5VBHHI8MR2b0jGw4Pl2lMKoyg51qmxG7M8npBRNjfTrNohTwqmpTy0SvPJyf/5X Eb0piq76H0TiHWzJa5vohDZ2OLNxv60jYc5IZQpK6yKbnKUUsMTrSP7PbWSfnPa3E6DdI /AvdgTpfWOzV1BZqkBYW+GLhSeRsr8B0iIUiEIF6jfR+MtA8gMYbYmK0vuSkafEZzXA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=tZCzVwGJ; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EFD07606EAAF; Fri, 13 Nov 2026 16:04:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=tZCzVwGJ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 56A781F000C4; Fri, 13 Nov 2026 16:04:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794585898; bh=I4RDqc99Iemnn+j0KFG9CY/5UMe8CW4PC20keqzeLj4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=tZCzVwGJCoXWDwhEIwFcJtA1z7vRo/N5Qcws48iVAcZQZUMWTLgwJIm1W/fJTDhLS Xp6myhSQw3j6cqGSrcLZzlHsrShOZhzzQnw8ajlVHtWZ9m4vya6ie35p2LrrDu+nCs 3Zc1RRhSp5xSspLprIMTp0vhTyh5OF4I8Ge9TtGk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Kyle Zeng , "Matthieu Baerts (NGI0)" , Paolo Abeni , Sasha Levin Subject: [PATCH 7.3 411/507] mptcp: pm: kernel: use RCU to free endpoint listeners Date: Fri, 13 Nov 2026 10:51:55 -0500 Message-ID: <20261113153810.667019509@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153753.358973689@linuxfoundation.org> References: <20261113153753.358973689@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kyle Zeng [ Upstream commit 49b09ae0bf57b4230187d4cdd0a370558e44a6e8 ] mptcp_pm_nl_create_listen_socket() starts the TCP listener directly instead of going through mptcp_listen(). It consequently misses setting SOCK_RCU_FREE on the parent MPTCP socket. tcp_child_process() can invoke the listener's subflow_data_ready() callback without holding the MPTCP parent lock or a reference to the parent. An authenticated MP_JOIN racing with endpoint teardown can therefore access the parent after its last reference has been dropped. The ADD_ADDR error path can also close an already published listener. Set SOCK_RCU_FREE before __inet_listen_sk() publishes the TCP listener, matching mptcp_listen(). This protects the parent on every subsequent close path, including a failed endpoint addition. Fixes: 1729cf186d8a ("mptcp: create the listening socket for new port") Cc: stable@vger.kernel.org Signed-off-by: Kyle Zeng Reviewed-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20261030042255.74216-1-kylebot@openai.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/mptcp/pm_kernel.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/mptcp/pm_kernel.c b/net/mptcp/pm_kernel.c index 1a77508132354..f7396628490e3 100644 --- a/net/mptcp/pm_kernel.c +++ b/net/mptcp/pm_kernel.c @@ -906,6 +906,7 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk, * old status is known (TCP_CLOSE). */ inet_sk_state_store(newsk, TCP_LISTEN); + sock_set_flag(newsk, SOCK_RCU_FREE); lock_sock(ssk); WRITE_ONCE(mptcp_subflow_ctx(ssk)->pm_listener, true); err = __inet_listen_sk(ssk, backlog); -- 2.53.0