From mboxrd@z Thu Jan 1 00:00:00 1970 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=-24.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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=unavailable 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 C33F5C43603 for ; Fri, 19 Mar 2021 12:21:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD0CD64F8B for ; Fri, 19 Mar 2021 12:21:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231482AbhCSMVT (ORCPT ); Fri, 19 Mar 2021 08:21:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:59320 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231154AbhCSMUv (ORCPT ); Fri, 19 Mar 2021 08:20:51 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C8B0964F6E; Fri, 19 Mar 2021 12:20:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1616156451; bh=nY6YsqPYxFmKHe2OjtlwfkshWJEhQXXf+JGu0beZnkA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TuoKzhyC0RU8ZLFr6nmFMM7V9UUppXmyrOmMRN67vXEqJpkESFqV7zeKnZTiQ9jik jhz3lJNi8J6aQvcB3VjQBAMi5TH3SpCeoqHyzJuyafdvyGkUZq7jASf4guCc3gAASf evoD4T75Hr8otd7P/oU0k7GiW+gQPku+3/iHM/3E= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christoph Paasch , Paolo Abeni , Florian Westphal , Mat Martineau , "David S. Miller" , Sasha Levin Subject: [PATCH 5.11 06/31] mptcp: dispose initial struct socket when its subflow is closed Date: Fri, 19 Mar 2021 13:19:00 +0100 Message-Id: <20210319121747.415250250@linuxfoundation.org> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20210319121747.203523570@linuxfoundation.org> References: <20210319121747.203523570@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Florian Westphal [ Upstream commit 17aee05dc8822e354f5ad2d68ee39e3ba4b6acf2 ] 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 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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 64b8a49652ae..7345df40385a 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2100,6 +2100,14 @@ 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). * @@ -2144,6 +2152,9 @@ 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); } static unsigned int mptcp_sync_mss(struct sock *sk, u32 pmtu) @@ -2533,12 +2544,6 @@ 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(). */ @@ -2563,6 +2568,7 @@ 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); } -- 2.30.1