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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A06DECCA47E for ; Tue, 7 Jun 2022 17:53:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347803AbiFGRxA (ORCPT ); Tue, 7 Jun 2022 13:53:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349933AbiFGRvm (ORCPT ); Tue, 7 Jun 2022 13:51:42 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 69A7E13CA1C; Tue, 7 Jun 2022 10:39:13 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E34426160E; Tue, 7 Jun 2022 17:38:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EB61FC385A5; Tue, 7 Jun 2022 17:38:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654623497; bh=9o9q4WD8l/Xb1LIFiZ7mZPfpN8Qs+Tj9o9Js+pnAarU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GbkgruOBNMotBLTmZ7etrqagZxvYU7OFsorDD0fU3uSLLNhsJZGnFOb6OedSDaYpg x5fmDDChQ91myVXFeekv6IYoahTyjHNK/jL+sSTHVUn5IkbykPgybQmLQvdyeGvrrf yD1sN1mZy25s0B27yTAehKFjwrQUyVI3C0Bhg0Vs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ziyang Xuan , kernel test robot , Daniel Lezcano Subject: [PATCH 5.10 439/452] thermal/core: fix a UAF bug in __thermal_cooling_device_register() Date: Tue, 7 Jun 2022 19:04:56 +0200 Message-Id: <20220607164921.644649330@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607164908.521895282@linuxfoundation.org> References: <20220607164908.521895282@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: Ziyang Xuan commit 0a5c26712f963f0500161a23e0ffff8d29f742ab upstream. When device_register() return failed, program will goto out_kfree_type to release 'cdev->device' by put_device(). That will call thermal_release() to free 'cdev'. But the follow-up processes access 'cdev' continually. That trggers the UAF bug. ==================================================================== BUG: KASAN: use-after-free in __thermal_cooling_device_register+0x75b/0xa90 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: dump_stack_lvl+0xe2/0x152 print_address_description.constprop.0+0x21/0x140 ? __thermal_cooling_device_register+0x75b/0xa90 kasan_report.cold+0x7f/0x11b ? __thermal_cooling_device_register+0x75b/0xa90 __thermal_cooling_device_register+0x75b/0xa90 ? memset+0x20/0x40 ? __sanitizer_cov_trace_pc+0x1d/0x50 ? __devres_alloc_node+0x130/0x180 devm_thermal_of_cooling_device_register+0x67/0xf0 max6650_probe.cold+0x557/0x6aa ...... Freed by task 258: kasan_save_stack+0x1b/0x40 kasan_set_track+0x1c/0x30 kasan_set_free_info+0x20/0x30 __kasan_slab_free+0x109/0x140 kfree+0x117/0x4c0 thermal_release+0xa0/0x110 device_release+0xa7/0x240 kobject_put+0x1ce/0x540 put_device+0x20/0x30 __thermal_cooling_device_register+0x731/0xa90 devm_thermal_of_cooling_device_register+0x67/0xf0 max6650_probe.cold+0x557/0x6aa [max6650] Do not use 'cdev' again after put_device() to fix the problem like doing in thermal_zone_device_register(). [dlezcano]: as requested by Rafael, change the affectation into two statements. Fixes: 584837618100 ("thermal/drivers/core: Use a char pointer for the cooling device name") Signed-off-by: Ziyang Xuan Reported-by: kernel test robot Link: https://lore.kernel.org/r/20211015024504.947520-1-william.xuanziyang@huawei.com Signed-off-by: Daniel Lezcano Signed-off-by: Greg Kroah-Hartman --- drivers/thermal/thermal_core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -1092,7 +1092,7 @@ __thermal_cooling_device_register(struct { struct thermal_cooling_device *cdev; struct thermal_zone_device *pos = NULL; - int ret; + int id, ret; if (!ops || !ops->get_max_state || !ops->get_cur_state || !ops->set_cur_state) @@ -1106,6 +1106,7 @@ __thermal_cooling_device_register(struct if (ret < 0) goto out_kfree_cdev; cdev->id = ret; + id = ret; cdev->type = kstrdup(type ? type : "", GFP_KERNEL); if (!cdev->type) { @@ -1147,8 +1148,9 @@ out_kfree_type: thermal_cooling_device_destroy_sysfs(cdev); kfree(cdev->type); put_device(&cdev->device); + cdev = NULL; out_ida_remove: - ida_simple_remove(&thermal_cdev_ida, cdev->id); + ida_simple_remove(&thermal_cdev_ida, id); out_kfree_cdev: return ERR_PTR(ret); }