From patchwork Thu Mar 4 21:32:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mat Martineau X-Patchwork-Id: 12116823 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-21.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 80145C433E6 for ; Thu, 4 Mar 2021 21:36:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D09064FF0 for ; Thu, 4 Mar 2021 21:36:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239573AbhCDVgF (ORCPT ); Thu, 4 Mar 2021 16:36:05 -0500 Received: from mga12.intel.com ([192.55.52.136]:5337 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239567AbhCDVfy (ORCPT ); Thu, 4 Mar 2021 16:35:54 -0500 IronPort-SDR: 9kjROWACgdZTHU6dAuM1OCxmTfCqcdg9nVcwxIxCXMJxlTtOdhDJd4+3aXSCKa5Y38SVOwMnuT 7f8A+SOrvbRQ== X-IronPort-AV: E=McAfee;i="6000,8403,9913"; a="166769417" X-IronPort-AV: E=Sophos;i="5.81,223,1610438400"; d="scan'208";a="166769417" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Mar 2021 13:32:24 -0800 IronPort-SDR: g36bec/vFOZmQ+P+UHuyl2Xhf4V6FtezIF/a+x2RPW8Z+V5NmeTJrTxrxJYUcirXgaGiOqjFz6 9UML8fiRP/lQ== X-IronPort-AV: E=Sophos;i="5.81,223,1610438400"; d="scan'208";a="368329482" Received: from mjmartin-desk2.amr.corp.intel.com (HELO mjmartin-desk2.intel.com) ([10.254.105.71]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Mar 2021 13:32:22 -0800 From: Mat Martineau To: netdev@vger.kernel.org Cc: Florian Westphal , davem@davemloft.net, kuba@kernel.org, matthieu.baerts@tessares.net, mptcp@lists.01.org, Christoph Paasch , Paolo Abeni , Mat Martineau Subject: [PATCH net 4/9] mptcp: dispose initial struct socket when its subflow is closed Date: Thu, 4 Mar 2021 13:32:11 -0800 Message-Id: <20210304213216.205472-5-mathew.j.martineau@linux.intel.com> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210304213216.205472-1-mathew.j.martineau@linux.intel.com> References: <20210304213216.205472-1-mathew.j.martineau@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Florian Westphal Christoph Paasch reported following crash: dst_release underflow WARNING: CPU: 0 PID: 1319 at net/core/dst.c:175 dst_release+0xc1/0xd0 net/core/dst.c:175 CPU: 0 PID: 1319 Comm: syz-executor217 Not tainted 5.11.0-rc6af8e85128b4d0d24083c5cac646e891227052e0c #70 Call Trace: rt_cache_route+0x12e/0x140 net/ipv4/route.c:1503 rt_set_nexthop.constprop.0+0x1fc/0x590 net/ipv4/route.c:1612 __mkroute_output net/ipv4/route.c:2484 [inline] ... The worker leaves msk->subflow alone even when it happened to close the subflow ssk associated with it. Fixes: 866f26f2a9c33b ("mptcp: always graft subflow socket to parent") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/157 Reported-by: Christoph Paasch Suggested-by: Paolo Abeni Acked-by: Paolo Abeni Signed-off-by: Florian Westphal Signed-off-by: Mat Martineau --- net/mptcp/protocol.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index aa59101ffe54..a58da04bed71 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2116,6 +2116,14 @@ static struct sock *mptcp_subflow_get_retrans(const struct mptcp_sock *msk) return backup; } +static void mptcp_dispose_initial_subflow(struct mptcp_sock *msk) +{ + if (msk->subflow) { + iput(SOCK_INODE(msk->subflow)); + msk->subflow = NULL; + } +} + /* subflow sockets can be either outgoing (connect) or incoming * (accept). * @@ -2160,6 +2168,9 @@ static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk, if (ssk == msk->last_snd) msk->last_snd = NULL; + + if (msk->subflow && ssk == msk->subflow->sk) + mptcp_dispose_initial_subflow(msk); } void mptcp_close_ssk(struct sock *sk, struct sock *ssk, @@ -2529,12 +2540,6 @@ static void __mptcp_destroy_sock(struct sock *sk) might_sleep(); - /* dispose the ancillatory tcp socket, if any */ - if (msk->subflow) { - iput(SOCK_INODE(msk->subflow)); - msk->subflow = NULL; - } - /* be sure to always acquire the join list lock, to sync vs * mptcp_finish_join(). */ @@ -2559,6 +2564,7 @@ static void __mptcp_destroy_sock(struct sock *sk) sk_stream_kill_queues(sk); xfrm_sk_free_policy(sk); sk_refcnt_debug_release(sk); + mptcp_dispose_initial_subflow(msk); sock_put(sk); }