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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 35ABFC43441 for ; Sun, 11 Nov 2018 20:37:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 049C420869 for ; Sun, 11 Nov 2018 20:37:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 049C420869 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730092AbeKLFsK (ORCPT ); Mon, 12 Nov 2018 00:48:10 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:49656 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730053AbeKLFsK (ORCPT ); Mon, 12 Nov 2018 00:48:10 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gLvsW-0000l8-Bh; Sun, 11 Nov 2018 19:58:40 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gLvsT-0001bD-7q; Sun, 11 Nov 2018 19:58:37 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Chas Williams" <3chas3@gmail.com>, "David S. Miller" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 169/366] net/xen-netfront: only clean up queues if present In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Chas Williams <3chas3@gmail.com> commit 9a873c71e91cabf4c10fd9bbd8358c22deaf6c9e upstream. If you simply load and unload the module without starting the interfaces, the queues are never created and you get a bad pointer dereference. Signed-off-by: Chas Williams <3chas3@gmail.com> Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- drivers/net/xen-netfront.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1422,7 +1422,7 @@ static void xennet_disconnect_backend(st netif_carrier_off(info->netdev); - for (i = 0; i < num_queues; ++i) { + for (i = 0; i < num_queues && info->queues; ++i) { struct netfront_queue *queue = &info->queues[i]; del_timer_sync(&queue->rx_refill_timer); @@ -2294,7 +2294,8 @@ static int xennet_remove(struct xenbus_d unregister_netdev(info->netdev); - xennet_destroy_queues(info); + if (info->queues) + xennet_destroy_queues(info); xennet_free_netdev(info->netdev); return 0;