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=-8.5 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 E9900C282C0 for ; Fri, 25 Jan 2019 20:35:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AAA0E218FF for ; Fri, 25 Jan 2019 20:35:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=mvista-com.20150623.gappssmtp.com header.i=@mvista-com.20150623.gappssmtp.com header.b="gt2e+PgX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729202AbfAYUfc (ORCPT ); Fri, 25 Jan 2019 15:35:32 -0500 Received: from mail-ot1-f65.google.com ([209.85.210.65]:34064 "EHLO mail-ot1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726179AbfAYUfb (ORCPT ); Fri, 25 Jan 2019 15:35:31 -0500 Received: by mail-ot1-f65.google.com with SMTP id t5so9759475otk.1 for ; Fri, 25 Jan 2019 12:35:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mvista-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:reply-to:references:mime-version :content-disposition:in-reply-to:user-agent; bh=V7Zz6B4ep/S9lo2cEqRIuyWB8Oo9z82Zia2aFv4SK0M=; b=gt2e+PgXjIbm7TYJ2AND6hu+hnnpvm9LASQWkcVJ0IyNrBFsg+5dw5OBoQdNTmY1eS VVBteq4a4G9MokMZlU2/R4nmxC0tubl4S2Qf5NEiv9eA3aKZMfGrudboTevUnkSjn5xq HazaqnFF02cvmoSbBzIi3NxZq4utCN6x+RyEl8SFfZwCrftj5wLrJYZWaBmxC7LAOm0u zA0ChV4mpETT2EY4mF1/i05CbydM+bxUo4YiGs2IQbbJ2DatzL/v1BgnMV1NtkMnVeNx Stka32Nm2la4dEUfLzWqBBPTKLWA4ilAWgo5xhyhI96j6fdVcSbwm19PVc0wri2fcfHh 5VIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:reply-to :references:mime-version:content-disposition:in-reply-to:user-agent; bh=V7Zz6B4ep/S9lo2cEqRIuyWB8Oo9z82Zia2aFv4SK0M=; b=cf5Vin0GCIvM5qdJ51uhvRNqJy0SfTPrMFciSm3D/fcz8Oz77kxU2LH7hX+wUHI9b2 6HLlDWmJrJAQzab19bOkO3j1GstWwSGwqcP7a62ZKxPQodNkBUw3d1DU1RV9AGWlFhj7 GLWkeOSS0cDv7LwlLblWRZI3rYWYt8ForaSCQWH+nDQcov0jVI04SXIPFFCFspmpZqof vwV+41MCvN+ulFtI0GcCdtYkWfGzzROV/aoCQICRlTbAhazJkJlK+q4gxHGGSvYbJxKI IwaABYRykr15jrYkCd7BeISvcHbfoslG5xzSxUmNHuPew9UQWpD9dG7sWpeSY2U8vd1U Uhng== X-Gm-Message-State: AJcUukfyhTDXdvGx6d9/pn97a10sYdaNGXzjTW9ZHEYlhz1xBELiPtoE DGSn1SS2g3x2e/Yx0Njy6/Mm2w== X-Google-Smtp-Source: ALg8bN69G3lnM7aJqDk/rPyMLx6EsXng3ItsywYGfGYkfI6jFRXZ7jqTKiVK3MPN1wVZNVaGch1xjg== X-Received: by 2002:a05:6830:165a:: with SMTP id h26mr9287581otr.299.1548448527527; Fri, 25 Jan 2019 12:35:27 -0800 (PST) Received: from minyard.net ([2001:470:b8f6:1b:a64e:31ff:fe14:d744]) by smtp.gmail.com with ESMTPSA id r9sm1746527otq.81.2019.01.25.12.35.25 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 25 Jan 2019 12:35:26 -0800 (PST) Date: Fri, 25 Jan 2019 14:35:24 -0600 From: Corey Minyard To: Yang Yingliang Cc: arnd@arndb.de, gregkh@linuxfoundation.org, openipmi-developer@lists.sourceforge.net, linux-kernel@vger.kernel.org, stable@vger.kernel.org, qiaonuohan@huawei.com Subject: Re: [PATCH] ipmi_si: fix use-after-free of resource->name Message-ID: <20190125203524.GA20851@minyard.net> Reply-To: cminyard@mvista.com References: <1548383459-38420-1-git-send-email-yangyingliang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1548383459-38420-1-git-send-email-yangyingliang@huawei.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 25, 2019 at 10:30:59AM +0800, Yang Yingliang wrote: > When we excute the following commands, we got oops > rmmod ipmi_si > cat /proc/ioports > snip... > > If io_setup is called successful in try_smi_init() but try_smi_init() > goes out_err before calling ipmi_register_smi(), so ipmi_unregister_smi() > will not be called while removing module. It leads to the resource that > allocated in io_setup() can not be freed, but the name(DEVICE_NAME) of > resource is freed while removing the module. It causes use-after-free > when cat /proc/ioports. > > Fix this by calling shutdown_smi() while removing the module and don't > call release_region() if request_region() is not called to avoid error > prints. > > Fixes: 93c303d2045b ("ipmi_si: Clean up shutdown a bit") > Cc: stable@vger.kernel.org > Reported-by: NuoHan Qiao > Signed-off-by: Yang Yingliang > --- > drivers/char/ipmi/ipmi_si_intf.c | 2 ++ > drivers/char/ipmi/ipmi_si_port_io.c | 3 +++ > 2 files changed, 5 insertions(+) > > diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c > index dc8603d..635e98a 100644 > --- a/drivers/char/ipmi/ipmi_si_intf.c > +++ b/drivers/char/ipmi/ipmi_si_intf.c > @@ -2235,6 +2235,8 @@ static void cleanup_one_si(struct smi_info *smi_info) > > if (smi_info->intf) > ipmi_unregister_smi(smi_info->intf); > + else > + shutdown_smi(smi_info); This is completely the wrong way to fix this. The general principle is that a function cleans up for itself if it returns an error. If you add hacks other places for a function failing you end up with a mess. I think the right way to fix this is to add something like: if (rv && new_smi->io.io_size && smi_info->io.io_cleanup) { smi_info->io.io_cleanup(&smi_info->io); smi_info->io.io_cleanup = NULL; } at the end of try_smi_init(). -corey > > if (smi_info->pdev) { > if (smi_info->pdev_registered) > diff --git a/drivers/char/ipmi/ipmi_si_port_io.c b/drivers/char/ipmi/ipmi_si_port_io.c > index ef6dffc..0c46a3f 100644 > --- a/drivers/char/ipmi/ipmi_si_port_io.c > +++ b/drivers/char/ipmi/ipmi_si_port_io.c > @@ -53,6 +53,9 @@ static void port_cleanup(struct si_sm_io *io) > unsigned int addr = io->addr_data; > int idx; > > + if (io->regsize != 1 && io->regsize != 2 && io->regsize != 4) > + return; > + > if (addr) { > for (idx = 0; idx < io->io_size; idx++) > release_region(addr + idx * io->regspacing, > -- > 1.8.3 > >