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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 0DDEEC2D0F9 for ; Wed, 13 May 2020 09:48:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA26820740 for ; Wed, 13 May 2020 09:48:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589363337; bh=6Nj0ivymC0ECNsWFCc3YPYlbmxZtWC1YnpOr92BuU0g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kX//3MJJzpeMZ6MZRWjaUvOQ91FPhqHpbmqVOOE3HS32BsoEGs8t2NMWYwkBjA2yH 4pjlXUnuc3kwVDZuRb7fi+XoQjknFgIihn+LOUNA4zCSot5H4bNed1aNAxoSobitJM I660B6ejHapRwZSNfZuxzTR1tcafdmgZnEqt0KZA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733153AbgEMJs5 (ORCPT ); Wed, 13 May 2020 05:48:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:47418 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733126AbgEMJst (ORCPT ); Wed, 13 May 2020 05:48:49 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A9F1320753; Wed, 13 May 2020 09:48:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589363328; bh=6Nj0ivymC0ECNsWFCc3YPYlbmxZtWC1YnpOr92BuU0g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a/mUl48VaZ91nIMJvJoW7V85Lzvjoi3xcevLEbAXwQLMhc8709iKZZjAcvNiIMDD3 AA2z2aUeNRDqlHhHKkYQkH2f0AWX/sh59B6ujLSh1Nflm9JYDGfzUEzr7k/ynpbKQ9 8KSfNJa/l+Br+4fqAZBKRGAMgtStgzH/mMb5gxmk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jon Maloy , Ying Xue , Tuong Lien , "David S. Miller" Subject: [PATCH 5.4 29/90] tipc: fix partial topology connection closure Date: Wed, 13 May 2020 11:44:25 +0200 Message-Id: <20200513094411.572153309@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200513094408.810028856@linuxfoundation.org> References: <20200513094408.810028856@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tuong Lien [ Upstream commit 980d69276f3048af43a045be2925dacfb898a7be ] When an application connects to the TIPC topology server and subscribes to some services, a new connection is created along with some objects - 'tipc_subscription' to store related data correspondingly... However, there is one omission in the connection handling that when the connection or application is orderly shutdown (e.g. via SIGQUIT, etc.), the connection is not closed in kernel, the 'tipc_subscription' objects are not freed too. This results in: - The maximum number of subscriptions (65535) will be reached soon, new subscriptions will be rejected; - TIPC module cannot be removed (unless the objects are somehow forced to release first); The commit fixes the issue by closing the connection if the 'recvmsg()' returns '0' i.e. when the peer is shutdown gracefully. It also includes the other unexpected cases. Acked-by: Jon Maloy Acked-by: Ying Xue Signed-off-by: Tuong Lien Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/tipc/topsrv.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/net/tipc/topsrv.c +++ b/net/tipc/topsrv.c @@ -402,10 +402,11 @@ static int tipc_conn_rcv_from_sock(struc read_lock_bh(&sk->sk_callback_lock); ret = tipc_conn_rcv_sub(srv, con, &s); read_unlock_bh(&sk->sk_callback_lock); + if (!ret) + return 0; } - if (ret < 0) - tipc_conn_close(con); + tipc_conn_close(con); return ret; }