From patchwork Fri Mar 6 12:06:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Wunderlich X-Patchwork-Id: 222941 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 15C6FC10DCE for ; Fri, 6 Mar 2020 12:15:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6D142072D for ; Fri, 6 Mar 2020 12:15:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726485AbgCFMPT (ORCPT ); Fri, 6 Mar 2020 07:15:19 -0500 Received: from simonwunderlich.de ([79.140.42.25]:44540 "EHLO simonwunderlich.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726026AbgCFMPS (ORCPT ); Fri, 6 Mar 2020 07:15:18 -0500 Received: from kero.packetmixer.de (p200300C597077300B0A48B46F0435C76.dip0.t-ipconnect.de [IPv6:2003:c5:9707:7300:b0a4:8b46:f043:5c76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by simonwunderlich.de (Postfix) with ESMTPSA id 3B7E762059; Fri, 6 Mar 2020 13:06:20 +0100 (CET) From: Simon Wunderlich To: davem@davemloft.net Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Sven Eckelmann , syzbot+a98f2016f40b9cd3818a@syzkaller.appspotmail.com, syzbot+ac36b6a33c28a491e929@syzkaller.appspotmail.com, Hillf Danton , Simon Wunderlich Subject: [PATCH 1/1] batman-adv: Don't schedule OGM for disabled interface Date: Fri, 6 Mar 2020 13:06:18 +0100 Message-Id: <20200306120618.25714-2-sw@simonwunderlich.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200306120618.25714-1-sw@simonwunderlich.de> References: <20200306120618.25714-1-sw@simonwunderlich.de> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sven Eckelmann A transmission scheduling for an interface which is currently dropped by batadv_iv_ogm_iface_disable could still be in progress. The B.A.T.M.A.N. V is simply cancelling the workqueue item in an synchronous way but this is not possible with B.A.T.M.A.N. IV because the OGM submissions are intertwined. Instead it has to stop submitting the OGM when it detect that the buffer pointer is set to NULL. Reported-by: syzbot+a98f2016f40b9cd3818a@syzkaller.appspotmail.com Reported-by: syzbot+ac36b6a33c28a491e929@syzkaller.appspotmail.com Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann Cc: Hillf Danton Signed-off-by: Simon Wunderlich --- net/batman-adv/bat_iv_ogm.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index f0209505e41a..a7c8dd7ae513 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -789,6 +789,10 @@ static void batadv_iv_ogm_schedule_buff(struct batadv_hard_iface *hard_iface) lockdep_assert_held(&hard_iface->bat_iv.ogm_buff_mutex); + /* interface already disabled by batadv_iv_ogm_iface_disable */ + if (!*ogm_buff) + return; + /* the interface gets activated here to avoid race conditions between * the moment of activating the interface in * hardif_activate_interface() where the originator mac is set and