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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 60E87ECE599 for ; Wed, 16 Oct 2019 22:19:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3836821925 for ; Wed, 16 Oct 2019 22:19:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571264343; bh=JlMX2lzPSZonYYQe8neGfCYmIhxJDq7CPBzUWvY4DJk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=J6A3tWhcUGsWJhijAen+f3enyR8jiEt0yOQ5BkRhOyB+w+qtL7bST5w9DR8/j7gUD IM1sYGKRuyc6bZr6WO7RHGUmcDelpmvZ9Jq9GXHRTENI33CaRND99ZWzBT/brgdqTW dqtlUMxC0en6846rkXYwwvFD1n33eHCiYV9jKKbs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394012AbfJPWTC (ORCPT ); Wed, 16 Oct 2019 18:19:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:44010 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2394953AbfJPVyR (ORCPT ); Wed, 16 Oct 2019 17:54:17 -0400 Received: from localhost (unknown [192.55.54.58]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D9C5B20872; Wed, 16 Oct 2019 21:54:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571262856; bh=JlMX2lzPSZonYYQe8neGfCYmIhxJDq7CPBzUWvY4DJk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GThWAOSaO4yFRpjmjF6tnLcsj/79J+CQzvKxFFbdB7PTtN9xIP+9l2NCWrc/Kax4R BcfgzwCs8QVrgwsJuO5F9FstnnBK7hbQbpNBiBqUJkifJzdwg7mAVUt0cnZaFuMHNM jNAAM40KN1tDeyIVZ/Z0sYS/rnI+U2IZVJ7/bx5I= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jiri Pirko , Ido Schimmel , Zhang Rui , Sasha Levin Subject: [PATCH 4.9 22/92] thermal: Fix use-after-free when unregistering thermal zone device Date: Wed, 16 Oct 2019 14:49:55 -0700 Message-Id: <20191016214818.632056648@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016214759.600329427@linuxfoundation.org> References: <20191016214759.600329427@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ido Schimmel [ Upstream commit 1851799e1d2978f68eea5d9dff322e121dcf59c1 ] thermal_zone_device_unregister() cancels the delayed work that polls the thermal zone, but it does not wait for it to finish. This is racy with respect to the freeing of the thermal zone device, which can result in a use-after-free [1]. Fix this by waiting for the delayed work to finish before freeing the thermal zone device. Note that thermal_zone_device_set_polling() is never invoked from an atomic context, so it is safe to call cancel_delayed_work_sync() that can block. [1] [ +0.002221] ================================================================== [ +0.000064] BUG: KASAN: use-after-free in __mutex_lock+0x1076/0x11c0 [ +0.000016] Read of size 8 at addr ffff8881e48e0450 by task kworker/1:0/17 [ +0.000023] CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.2.0-rc6-custom-02495-g8e73ca3be4af #1701 [ +0.000010] Hardware name: Mellanox Technologies Ltd. MSN2100-CB2FO/SA001017, BIOS 5.6.5 06/07/2016 [ +0.000016] Workqueue: events_freezable_power_ thermal_zone_device_check [ +0.000012] Call Trace: [ +0.000021] dump_stack+0xa9/0x10e [ +0.000020] print_address_description.cold.2+0x9/0x25e [ +0.000018] __kasan_report.cold.3+0x78/0x9d [ +0.000016] kasan_report+0xe/0x20 [ +0.000016] __mutex_lock+0x1076/0x11c0 [ +0.000014] step_wise_throttle+0x72/0x150 [ +0.000018] handle_thermal_trip+0x167/0x760 [ +0.000019] thermal_zone_device_update+0x19e/0x5f0 [ +0.000019] process_one_work+0x969/0x16f0 [ +0.000017] worker_thread+0x91/0xc40 [ +0.000014] kthread+0x33d/0x400 [ +0.000015] ret_from_fork+0x3a/0x50 [ +0.000020] Allocated by task 1: [ +0.000015] save_stack+0x19/0x80 [ +0.000015] __kasan_kmalloc.constprop.4+0xc1/0xd0 [ +0.000014] kmem_cache_alloc_trace+0x152/0x320 [ +0.000015] thermal_zone_device_register+0x1b4/0x13a0 [ +0.000015] mlxsw_thermal_init+0xc92/0x23d0 [ +0.000014] __mlxsw_core_bus_device_register+0x659/0x11b0 [ +0.000013] mlxsw_core_bus_device_register+0x3d/0x90 [ +0.000013] mlxsw_pci_probe+0x355/0x4b0 [ +0.000014] local_pci_probe+0xc3/0x150 [ +0.000013] pci_device_probe+0x280/0x410 [ +0.000013] really_probe+0x26a/0xbb0 [ +0.000013] driver_probe_device+0x208/0x2e0 [ +0.000013] device_driver_attach+0xfe/0x140 [ +0.000013] __driver_attach+0x110/0x310 [ +0.000013] bus_for_each_dev+0x14b/0x1d0 [ +0.000013] driver_register+0x1c0/0x400 [ +0.000015] mlxsw_sp_module_init+0x5d/0xd3 [ +0.000014] do_one_initcall+0x239/0x4dd [ +0.000013] kernel_init_freeable+0x42b/0x4e8 [ +0.000012] kernel_init+0x11/0x18b [ +0.000013] ret_from_fork+0x3a/0x50 [ +0.000015] Freed by task 581: [ +0.000013] save_stack+0x19/0x80 [ +0.000014] __kasan_slab_free+0x125/0x170 [ +0.000013] kfree+0xf3/0x310 [ +0.000013] thermal_release+0xc7/0xf0 [ +0.000014] device_release+0x77/0x200 [ +0.000014] kobject_put+0x1a8/0x4c0 [ +0.000014] device_unregister+0x38/0xc0 [ +0.000014] thermal_zone_device_unregister+0x54e/0x6a0 [ +0.000014] mlxsw_thermal_fini+0x184/0x35a [ +0.000014] mlxsw_core_bus_device_unregister+0x10a/0x640 [ +0.000013] mlxsw_devlink_core_bus_device_reload+0x92/0x210 [ +0.000015] devlink_nl_cmd_reload+0x113/0x1f0 [ +0.000014] genl_family_rcv_msg+0x700/0xee0 [ +0.000013] genl_rcv_msg+0xca/0x170 [ +0.000013] netlink_rcv_skb+0x137/0x3a0 [ +0.000012] genl_rcv+0x29/0x40 [ +0.000013] netlink_unicast+0x49b/0x660 [ +0.000013] netlink_sendmsg+0x755/0xc90 [ +0.000013] __sys_sendto+0x3de/0x430 [ +0.000013] __x64_sys_sendto+0xe2/0x1b0 [ +0.000013] do_syscall_64+0xa4/0x4d0 [ +0.000013] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ +0.000017] The buggy address belongs to the object at ffff8881e48e0008 which belongs to the cache kmalloc-2k of size 2048 [ +0.000012] The buggy address is located 1096 bytes inside of 2048-byte region [ffff8881e48e0008, ffff8881e48e0808) [ +0.000007] The buggy address belongs to the page: [ +0.000012] page:ffffea0007923800 refcount:1 mapcount:0 mapping:ffff88823680d0c0 index:0x0 compound_mapcount: 0 [ +0.000020] flags: 0x200000000010200(slab|head) [ +0.000019] raw: 0200000000010200 ffffea0007682008 ffffea00076ab808 ffff88823680d0c0 [ +0.000016] raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000 [ +0.000007] page dumped because: kasan: bad access detected [ +0.000012] Memory state around the buggy address: [ +0.000012] ffff8881e48e0300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000012] ffff8881e48e0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000012] >ffff8881e48e0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000008] ^ [ +0.000012] ffff8881e48e0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000012] ffff8881e48e0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ +0.000007] ================================================================== Fixes: b1569e99c795 ("ACPI: move thermal trip handling to generic thermal layer") Reported-by: Jiri Pirko Signed-off-by: Ido Schimmel Acked-by: Jiri Pirko Signed-off-by: Zhang Rui Signed-off-by: Sasha Levin --- drivers/thermal/thermal_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index cd82ae34ddfa3..57603be42c507 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -402,7 +402,7 @@ static void thermal_zone_device_set_polling(struct thermal_zone_device *tz, mod_delayed_work(system_freezable_wq, &tz->poll_queue, msecs_to_jiffies(delay)); else - cancel_delayed_work(&tz->poll_queue); + cancel_delayed_work_sync(&tz->poll_queue); } static void monitor_thermal_zone(struct thermal_zone_device *tz) -- 2.20.1