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=DKIM_SIGNED,DKIM_VALID, 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 26A8AC606CF for ; Wed, 10 Jul 2019 10:15:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E93FB2084B for ; Wed, 10 Jul 2019 10:15:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="g02Q3VmN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727294AbfGJKPU (ORCPT ); Wed, 10 Jul 2019 06:15:20 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:52425 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727290AbfGJKPU (ORCPT ); Wed, 10 Jul 2019 06:15:20 -0400 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.nyi.internal (Postfix) with ESMTP id 63671220CF; Wed, 10 Jul 2019 06:15:19 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Wed, 10 Jul 2019 06:15:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :message-id:mime-version:subject:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=nW+C5pL8jnkUnl7RK EAE7WuKZMkZkLjK79SntKeVd0I=; b=g02Q3VmNDooAi+iFjWRURSP9VDw+LI770 v8Ka11hzFtKMNjWU+aXrkXLyfSfp0CIgXbXygry6d0PnVKnWgqn3ILvwyTF3xKs0 //YiEyZuaW5qHE8vTlus5KgVzQwOEuiFYn9IpiNl8ylDqGZfqoVYu6ERZcnn3wRS Dy46aLnVMSqdMSHpnlDldhJD0WQ2s0rE7QDeMeWoyxXPAKgq38T/Oqc26593doxR OJnukOR48JRtE5O8kg3kEqxldbaC5IfTJTjL8hlD60Gwhduk8VnPJrF6AZaOWssd GOG1+d92uyuHR4/4l6K5aRp4XE0WSZlmI3KMYcZD6YB8E3EKJjpKA== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduvddrgeeigddvjecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhephffvufffkffoggfgsedtkeertdertd dtnecuhfhrohhmpefkughoucfutghhihhmmhgvlhcuoehiughoshgthhesihguohhstghh rdhorhhgqeenucfkphepudelfedrgeejrdduieehrddvhedunecurfgrrhgrmhepmhgrih hlfhhrohhmpehiughoshgthhesihguohhstghhrdhorhhgnecuvehluhhsthgvrhfuihii vgeptd X-ME-Proxy: Received: from splinter.mtl.com (unknown [193.47.165.251]) by mail.messagingengine.com (Postfix) with ESMTPA id 4F1CB380074; Wed, 10 Jul 2019 06:15:17 -0400 (EDT) From: Ido Schimmel To: linux-pm@vger.kernel.org Cc: rui.zhang@intel.com, edubezval@gmail.com, daniel.lezcano@linaro.org, jiri@mellanox.com, vadimp@mellanox.com, mlxsw@mellanox.com, Ido Schimmel Subject: [PATCH] thermal: Fix use-after-free when unregistering thermal zone device Date: Wed, 10 Jul 2019 13:14:52 +0300 Message-Id: <20190710101452.32748-1-idosch@idosch.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Ido Schimmel 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 --- 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 46cfb7de4eb2..f87f462c60c1 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -298,7 +298,7 @@ static void thermal_zone_device_set_polling(struct thermal_zone_device *tz, &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