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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5A19C433FE for ; Mon, 25 Oct 2021 19:22:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8E7406115C for ; Mon, 25 Oct 2021 19:22:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233284AbhJYTYb (ORCPT ); Mon, 25 Oct 2021 15:24:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:39974 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234577AbhJYTXA (ORCPT ); Mon, 25 Oct 2021 15:23:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C6481601FF; Mon, 25 Oct 2021 19:20:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1635189628; bh=uSDolIVcEtSHZGOgEFdG/ReG0f0rmtd01GIP2GotD1A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bE5gZ03bRcpaYlvrNG/m/52pqYLswii8cZ38knBDNuxnd9qDJPf4uRkoAG4sMs+Hm WB9Sp2jGTFbSKHnASxDIkV/Sg4BqLmfp+WnAuOHrZad000KftnkCLsnOGXbsxHb5eA SGGo053hCYpQ1fPJRUc7DQihT8nWfqEJ8b/Lvfj8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zheyu Ma , Marc Kleine-Budde Subject: [PATCH 4.9 33/50] can: peak_pci: peak_pci_remove(): fix UAF Date: Mon, 25 Oct 2021 21:14:20 +0200 Message-Id: <20211025190938.993672777@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211025190932.542632625@linuxfoundation.org> References: <20211025190932.542632625@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zheyu Ma commit 949fe9b35570361bc6ee2652f89a0561b26eec98 upstream. When remove the module peek_pci, referencing 'chan' again after releasing 'dev' will cause UAF. Fix this by releasing 'dev' later. The following log reveals it: [ 35.961814 ] BUG: KASAN: use-after-free in peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.963414 ] Read of size 8 at addr ffff888136998ee8 by task modprobe/5537 [ 35.965513 ] Call Trace: [ 35.965718 ] dump_stack_lvl+0xa8/0xd1 [ 35.966028 ] print_address_description+0x87/0x3b0 [ 35.966420 ] kasan_report+0x172/0x1c0 [ 35.966725 ] ? peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.967137 ] ? trace_irq_enable_rcuidle+0x10/0x170 [ 35.967529 ] ? peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.967945 ] __asan_report_load8_noabort+0x14/0x20 [ 35.968346 ] peak_pci_remove+0x16f/0x270 [peak_pci] [ 35.968752 ] pci_device_remove+0xa9/0x250 Fixes: e6d9c80b7ca1 ("can: peak_pci: add support of some new PEAK-System PCI cards") Link: https://lore.kernel.org/all/1634192913-15639-1-git-send-email-zheyuma97@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Zheyu Ma Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/sja1000/peak_pci.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/drivers/net/can/sja1000/peak_pci.c +++ b/drivers/net/can/sja1000/peak_pci.c @@ -736,16 +736,15 @@ static void peak_pci_remove(struct pci_d struct net_device *prev_dev = chan->prev_dev; dev_info(&pdev->dev, "removing device %s\n", dev->name); + /* do that only for first channel */ + if (!prev_dev && chan->pciec_card) + peak_pciec_remove(chan->pciec_card); unregister_sja1000dev(dev); free_sja1000dev(dev); dev = prev_dev; - if (!dev) { - /* do that only for first channel */ - if (chan->pciec_card) - peak_pciec_remove(chan->pciec_card); + if (!dev) break; - } priv = netdev_priv(dev); chan = priv->priv; }