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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 73ADEC433DB for ; Wed, 6 Jan 2021 00:06:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4150B22D58 for ; Wed, 6 Jan 2021 00:06:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727275AbhAFAGD (ORCPT ); Tue, 5 Jan 2021 19:06:03 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:52452 "EHLO mail.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727230AbhAFAGC (ORCPT ); Tue, 5 Jan 2021 19:06:02 -0500 Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) by mail.monkeyblade.net (Postfix) with ESMTPSA id F22AD4CE685B6; Tue, 5 Jan 2021 16:05:21 -0800 (PST) Date: Tue, 05 Jan 2021 16:05:21 -0800 (PST) Message-Id: <20210105.160521.1279064249478522010.davem@davemloft.net> To: zhutong@amazon.com Cc: sashal@kernel.org, edumazet@google.com, vvs@virtuozzo.com, netdev@vger.kernel.org, stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] neighbour: Disregard DEAD dst in neigh_update From: David Miller In-Reply-To: <20201230225415.GA490@ucf43ac461c9a53.ant.amazon.com> References: <20201230225415.GA490@ucf43ac461c9a53.ant.amazon.com> X-Mailer: Mew version 6.8 on Emacs 27.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.6.2 (mail.monkeyblade.net [0.0.0.0]); Tue, 05 Jan 2021 16:05:22 -0800 (PST) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Tong Zhu Date: Wed, 30 Dec 2020 17:54:23 -0500 > In 4.x kernel a dst in DST_OBSOLETE_DEAD state is associated > with loopback net_device and leads to loopback neighbour. It > leads to an ethernet header with all zero addresses. > > A very troubling case is working with mac80211 and ath9k. > A packet with all zero source MAC address to mac80211 will > eventually fail ieee80211_find_sta_by_ifaddr in ath9k (xmit.c). > As result, ath9k flushes tx queue (ath_tx_complete_aggr) without > updating baw (block ack window), damages baw logic and disables > transmission. > > Signed-off-by: Tong Zhu Please repost with an appropriate Fixes: tag. Thanks.