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 EF541C2D0FD for ; Wed, 13 May 2020 10:00:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C652720575 for ; Wed, 13 May 2020 10:00:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589364015; bh=bkmkk4bP/D3Sq7OZCDTSZpVQIw/X4y2O9aX1jXh4CDc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YbwZcRxnY0AvcfrCPw3ToGFAWnoB92ae4or6Akas8CyXuv16Pi4hddCAWSckXKvEo oCvNZXF4Y+z54qBps/7UfE9kAxrj0KSMo7czu2eITomZvBmSbSy4U3egO+X9t4nkoV lUIHU9Rt2IciJNQqrwnt2RXWAc/Clad7ATkAo5W4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387771AbgEMJwR (ORCPT ); Wed, 13 May 2020 05:52:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:53514 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387762AbgEMJwN (ORCPT ); Wed, 13 May 2020 05:52:13 -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 193F3206D6; Wed, 13 May 2020 09:52:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589363533; bh=bkmkk4bP/D3Sq7OZCDTSZpVQIw/X4y2O9aX1jXh4CDc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J6Eq7gy1yYINPeOLhGCReiMZKFDqtl1YB8FOnr4+77J4xnTGwowCaeIVt3/dtW1ET t2/5P9qXA9zQobxACbq/pvKGV6O41SDz1UOi8evYoo2ep3mXzXQ7ohYAu69Qt9aGxl Nt8FcjLDmEjQpCZypMLEm67r3y4I8jC5E5DyfoFs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Allen Pais , Florian Fainelli , "David S. Miller" Subject: [PATCH 5.6 022/118] net: dsa: Do not leave DSA master with NULL netdev_ops Date: Wed, 13 May 2020 11:44:01 +0200 Message-Id: <20200513094419.651633965@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200513094417.618129545@linuxfoundation.org> References: <20200513094417.618129545@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: Florian Fainelli [ Upstream commit 050569fc8384c8056bacefcc246bcb2dfe574936 ] When ndo_get_phys_port_name() for the CPU port was added we introduced an early check for when the DSA master network device in dsa_master_ndo_setup() already implements ndo_get_phys_port_name(). When we perform the teardown operation in dsa_master_ndo_teardown() we would not be checking that cpu_dp->orig_ndo_ops was successfully allocated and non-NULL initialized. With network device drivers such as virtio_net, this leads to a NPD as soon as the DSA switch hanging off of it gets torn down because we are now assigning the virtio_net device's netdev_ops a NULL pointer. Fixes: da7b9e9b00d4 ("net: dsa: Add ndo_get_phys_port_name() for CPU port") Reported-by: Allen Pais Signed-off-by: Florian Fainelli Tested-by: Allen Pais Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/dsa/master.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/dsa/master.c +++ b/net/dsa/master.c @@ -289,7 +289,8 @@ static void dsa_master_ndo_teardown(stru { struct dsa_port *cpu_dp = dev->dsa_ptr; - dev->netdev_ops = cpu_dp->orig_ndo_ops; + if (cpu_dp->orig_ndo_ops) + dev->netdev_ops = cpu_dp->orig_ndo_ops; cpu_dp->orig_ndo_ops = NULL; }