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=-5.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 CF04EC432C0 for ; Mon, 18 Nov 2019 03:21:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A8AB5206CC for ; Mon, 18 Nov 2019 03:21:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tKIWcTVd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726345AbfKRDVP (ORCPT ); Sun, 17 Nov 2019 22:21:15 -0500 Received: from mail-pj1-f68.google.com ([209.85.216.68]:43248 "EHLO mail-pj1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726266AbfKRDVP (ORCPT ); Sun, 17 Nov 2019 22:21:15 -0500 Received: by mail-pj1-f68.google.com with SMTP id a10so1053919pju.10; Sun, 17 Nov 2019 19:21:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=48DDJ4D4S0wYE8hxlSX2K0AyEjit/Lx1WwVnZYqsT+I=; b=tKIWcTVdlUNglY4T7xTItt1EokO0F0BFh+0tRyrNSllt1rWGK6pONI9ryn0ODwybI+ nYAE3Jp169TRLeByPK7RUzvFPxBqlaqdqAD8cI0HmFrFyIbTukYFZXfoI1+VR67+3omx 4xv+ctgCbaxoVrfdf7e/V9spby8F8HPxTgPPC2vFL7kYuPgM9tv4EAh4bk3GfeBvAvUd 2PWklx3VNiUCDijpsy99xTNwLtX9UScAyua297oD8wLLkl+JvIkeZ3uQaNqEf/RuIRQY WxjPXNMpKdlP+HMj/WOhUWk2WM4AQRyErQ74vJKkp0xdvD8ix9ozkA1URwBykdasuE1f hOtg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=48DDJ4D4S0wYE8hxlSX2K0AyEjit/Lx1WwVnZYqsT+I=; b=G2pR1f1pTcwRZKwmwGXp/Lxws3mqMbCbiUmHn8LNMUStOxCHHYTYhwmNs5s1HiQe+I H69Y1c3+XnqkUIhDQKx5CpGj4+vBW8cTU5wEaJnneaPKp8BoFmhaYzIfITEDvYwyf4II 3Jgxt80vgJ0eQxEUDRsM78qcmU4LCjY9llDwqbPiqMnBvppehA4C1A0GLVYvfmimaM4P 9XwQeieaWIGU3fJjFPFhiuBx3NHT0rzmUXQFZQK1RHI5U6Rj3SL9aPrwqqMfexZALxFn Yi814sZ8tUskKU+TMVflPuG7w4dMToXOmvQWCCktCLmhrcpctvHvfx+jSXe3ZMYwHtTW 8/AQ== X-Gm-Message-State: APjAAAUnkEWe05rjNia/TULvSnuxVrI6vEGod2tHk/Auw9bS2Ycbv7iE T524Zef8Y3BD8qauPay2hHA= X-Google-Smtp-Source: APXvYqyLqXWScSf+XWbQzxGoSJwp4nYlzU0v5ikM1XZHIGdOwpKlBh9HvQY9U3AyW06XnWbvX7mb8w== X-Received: by 2002:a17:90a:234c:: with SMTP id f70mr35952404pje.109.1574047274609; Sun, 17 Nov 2019 19:21:14 -0800 (PST) Received: from dahern-DO-MB.local ([2601:282:800:fd80:bd88:fb6d:6b19:f7d1]) by smtp.googlemail.com with ESMTPSA id u9sm18891455pfm.102.2019.11.17.19.21.13 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 17 Nov 2019 19:21:13 -0800 (PST) Subject: Re: [PATCH] vrf: Fix possible NULL pointer oops when delete nic To: "wangxiaogang (F)" , dsahern@kernel.org, shrijeet@gmail.com, davem@davemloft.net Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, hujunwei4@huawei.com, xuhanbing@huawei.com References: <60e827cb-2bba-2b7e-55dc-651103e9905f@huawei.com> <7fe948a8-debd-e336-9584-e66153e90701@gmail.com> From: David Ahern Message-ID: Date: Sun, 17 Nov 2019 20:21:12 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 11/17/19 8:16 PM, wangxiaogang (F) wrote: > > > On 2019/11/16 0:59, David Ahern wrote: >> On 11/14/19 11:22 PM, wangxiaogang (F) wrote: >>> diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c >>> index b8228f5..86c4b8c 100644 >>> --- a/drivers/net/vrf.c >>> +++ b/drivers/net/vrf.c >>> @@ -1427,6 +1427,9 @@ static int vrf_device_event(struct notifier_block *unused, >>> goto out; >>> >>> vrf_dev = netdev_master_upper_dev_get(dev); >>> + if (!vrf_dev) >>> + goto out; >>> + >>> vrf_del_slave(vrf_dev, dev); >>> } >>> out: >> >> BTW, I believe this is the wrong fix. A device can not be a VRF slave >> AND not have an upper device. Something is fundamentally wrong. >> >> > > this problem occurs when our testers deleted the NIC and vrf in parallel. > I will try to recurring this problem later. > The deletes are serial in the kernel due to the rtnl, but dev changes are under rcu...