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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,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 76810C282E3 for ; Thu, 23 May 2019 19:14:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4EC0A21841 for ; Thu, 23 May 2019 19:14:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558638890; bh=jMH2V8R1fuWoPmimjUQZRU65tG7hPgPWcO3zfI/9mnk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=f3Gks/hAo/oEbjOnca9ZDWGbTa30efF79143FeraxnRbaLWRQ+fHwGjqKRAZ3EsVi Td1d/5uXgGDRJGT901u2HvaWusjzgCOzhr9i2hXqM3ywCOlMc6B1naMunTfJcwzvLs DJEoSjE5uEAhg/7qrdgYLE43ODCNF2PH/Y8/Y7o0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388843AbfEWTOt (ORCPT ); Thu, 23 May 2019 15:14:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:48878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388821AbfEWTOp (ORCPT ); Thu, 23 May 2019 15:14:45 -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 1035C217D7; Thu, 23 May 2019 19:14:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558638884; bh=jMH2V8R1fuWoPmimjUQZRU65tG7hPgPWcO3zfI/9mnk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uyl8BKZce0dsLMzUURcn1Pa3VtoT9ucWeVFfsuYUB+ECSIqqN0w7ZKrfkXlqA1qdI SeKvhdXvc1RvfkANN0fAAnHbB2X5ngNjwklnqVQAMsVXR76D/KuD5cu23wsCGLWcl9 DPgrASirRtDqHI+0dezvMSuhndhBL28eMAn1kmVw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Junwei Hu , Wang Wang , Xiaogang Wang , "David S. Miller" Subject: [PATCH 4.19 011/114] tipc: switch order of device registration to fix a crash Date: Thu, 23 May 2019 21:05:10 +0200 Message-Id: <20190523181732.687297111@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190523181731.372074275@linuxfoundation.org> References: <20190523181731.372074275@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: Junwei Hu [ Upstream commit 7e27e8d6130c5e88fac9ddec4249f7f2337fe7f8 ] When tipc is loaded while many processes try to create a TIPC socket, a crash occurs: PANIC: Unable to handle kernel paging request at virtual address "dfff20000000021d" pc : tipc_sk_create+0x374/0x1180 [tipc] lr : tipc_sk_create+0x374/0x1180 [tipc] Exception class = DABT (current EL), IL = 32 bits Call trace: tipc_sk_create+0x374/0x1180 [tipc] __sock_create+0x1cc/0x408 __sys_socket+0xec/0x1f0 __arm64_sys_socket+0x74/0xa8 ... This is due to race between sock_create and unfinished register_pernet_device. tipc_sk_insert tries to do "net_generic(net, tipc_net_id)". but tipc_net_id is not initialized yet. So switch the order of the two to close the race. This can be reproduced with multiple processes doing socket(AF_TIPC, ...) and one process doing module removal. Fixes: a62fbccecd62 ("tipc: make subscriber server support net namespace") Signed-off-by: Junwei Hu Reported-by: Wang Wang Reviewed-by: Xiaogang Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/tipc/core.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) --- a/net/tipc/core.c +++ b/net/tipc/core.c @@ -129,10 +129,6 @@ static int __init tipc_init(void) if (err) goto out_netlink_compat; - err = tipc_socket_init(); - if (err) - goto out_socket; - err = tipc_register_sysctl(); if (err) goto out_sysctl; @@ -141,6 +137,10 @@ static int __init tipc_init(void) if (err) goto out_pernet; + err = tipc_socket_init(); + if (err) + goto out_socket; + err = tipc_bearer_setup(); if (err) goto out_bearer; @@ -148,12 +148,12 @@ static int __init tipc_init(void) pr_info("Started in single node mode\n"); return 0; out_bearer: + tipc_socket_stop(); +out_socket: unregister_pernet_subsys(&tipc_net_ops); out_pernet: tipc_unregister_sysctl(); out_sysctl: - tipc_socket_stop(); -out_socket: tipc_netlink_compat_stop(); out_netlink_compat: tipc_netlink_stop(); @@ -165,10 +165,10 @@ out_netlink: static void __exit tipc_exit(void) { tipc_bearer_cleanup(); + tipc_socket_stop(); unregister_pernet_subsys(&tipc_net_ops); tipc_netlink_stop(); tipc_netlink_compat_stop(); - tipc_socket_stop(); tipc_unregister_sysctl(); pr_info("Deactivated\n");