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 A4FE5C00140 for ; Mon, 8 Aug 2022 18:44:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244135AbiHHSov (ORCPT ); Mon, 8 Aug 2022 14:44:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42036 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244008AbiHHSop (ORCPT ); Mon, 8 Aug 2022 14:44:45 -0400 Received: from ssl.serverraum.org (ssl.serverraum.org [IPv6:2a01:4f8:151:8464::1:2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 163BDE2A; Mon, 8 Aug 2022 11:44:42 -0700 (PDT) Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 5D3E92224F; Mon, 8 Aug 2022 20:44:40 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1659984280; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UWoNgvMdfqDAxbR6k/hHBv3FXqYhiHMlRj43gtM2Wcw=; b=bBJKzXu97IPt0eYv7ORu6g2UXOatpq/MPbyJEG8Tstg1olVrBX0wK9mpmWmJw91ZRYx/vQ CerKP74gDA9XIZGW5a9dI09fE4DuDa/O3H95vMfg3C77OJmJKuzvmUawwLHRPoXTSkXeZO V8zAWU5eB+z8aG1zkDEoNs5mZ105dPc= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 08 Aug 2022 20:44:40 +0200 From: Michael Walle To: Daniel Lezcano Cc: rafael@kernel.org, dan.carpenter@oracle.com, linux@roeck-us.net, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Amit Kucheria , Zhang Rui Subject: Re: [PATCH 4/4] thermal/of: Fix free after use in thermal_of_unregister() In-Reply-To: <20220808180915.446053-4-daniel.lezcano@linaro.org> References: <20220808180915.446053-1-daniel.lezcano@linaro.org> <20220808180915.446053-4-daniel.lezcano@linaro.org> User-Agent: Roundcube Webmail/1.4.13 Message-ID: <2a4c16bd886dd5b4bbf5bb12fd3b2e05@walle.cc> X-Sender: michael@walle.cc Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 2022-08-08 20:09, schrieb Daniel Lezcano: > The thermal zone is freed after being unregistered. The release method > devm_thermal_zone_device_register() calls > -> thermal_of_zone_device_unregister() > > This one calls thermal_zone_device_unregister() which frees the > thermal zone. However, thermal_of_zone_device_unregister() does access > this freed pointer to free different resources allocated by the > thermal_of framework which is invalid. > > It results in a kernel panic: > > [ 1.915140] thermal_sys: Failed to find thermal zone for tmu id=2 > [ 1.921279] qoriq_thermal 1f80000.tmu: Failed to register sensors > [ 1.927395] qoriq_thermal: probe of 1f80000.tmu failed with error > -22 > [ 1.934189] Unable to handle kernel paging request at virtual > address 01adadadadadad88 > [ 1.942146] Mem abort info: > [ 1.944948] ESR = 0x0000000096000004 > [ 1.948708] EC = 0x25: DABT (current EL), IL = 32 bits > [ 1.954042] SET = 0, FnV = 0 > [ 1.957107] EA = 0, S1PTW = 0 > [ 1.960253] FSC = 0x04: level 0 translation fault > [ 1.965147] Data abort info: > [ 1.968030] ISV = 0, ISS = 0x00000004 > [ 1.971878] CM = 0, WnR = 0 > [ 1.974852] [01adadadadadad88] address between user and kernel > address ranges > [ 1.982016] Internal error: Oops: 96000004 [#1] SMP > [ 1.986907] Modules linked in: > [ 1.989969] CPU: 1 PID: 1 Comm: swapper/0 Not tainted > 5.19.0-next-20220808-00080-g1c46f44502e0 #1697 > [ 1.999135] Hardware name: Kontron KBox A-230-LS (DT) > [ 2.004199] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS > BTYPE=--) > [ 2.011185] pc : kfree+0x5c/0x3c0 > [ 2.014516] lr : devm_thermal_of_zone_release+0x38/0x60 > [ 2.019761] sp : ffff80000a22bad0 > [ 2.023081] x29: ffff80000a22bad0 x28: 0000000000000000 x27: > ffff800009960464 > [ 2.030245] x26: ffff800009a16960 x25: 0000000000000006 x24: > ffff800009f09a40 > [ 2.037407] x23: ffff800009ab9008 x22: ffff800008d0eea8 x21: > 01adadadadadad80 > [ 2.044569] x20: 6b6b6b6b6b6b6b6b x19: ffff00200232b800 x18: > 00000000fffffffb > [ 2.051731] x17: ffff800008d0eea0 x16: ffff800008d07d44 x15: > ffff800008d0d154 > [ 2.056647] usb 1-1: new high-speed USB device number 2 using > xhci-hcd > [ 2.058893] x14: ffff800008d0cddc x13: ffff8000088d1c2c x12: > ffff8000088d5034 > [ 2.072597] x11: ffff8000088d46d4 x10: 0000000000000000 x9 : > ffff800008d0eea8 > [ 2.079759] x8 : ffff002000b1a158 x7 : bbbbbbbbbbbbbbbb x6 : > ffff80000a0f53b8 > [ 2.086921] x5 : ffff80000a22b960 x4 : 0000000000000000 x3 : > 0000000000000000 > [ 2.094082] x2 : fffffc0000000000 x1 : ffff002000838040 x0 : > 01adb1adadadad80 > [ 2.101244] Call trace: > [ 2.103692] kfree+0x5c/0x3c0 > [ 2.106666] devm_thermal_of_zone_release+0x38/0x60 > [ 2.111561] release_nodes+0x64/0xd0 > [ 2.115146] devres_release_all+0xbc/0x350 > [ 2.119253] device_unbind_cleanup+0x20/0x70 > [ 2.123536] really_probe+0x1a0/0x2e4 > [ 2.127208] __driver_probe_device+0x80/0xec > [ 2.131490] driver_probe_device+0x44/0x130 > [ 2.135685] __driver_attach+0x104/0x1b4 > [ 2.139619] bus_for_each_dev+0x7c/0xe0 > [ 2.143465] driver_attach+0x30/0x40 > [ 2.147048] bus_add_driver+0x160/0x210 > [ 2.150894] driver_register+0x84/0x140 > [ 2.154741] __platform_driver_register+0x34/0x40 > [ 2.159461] qoriq_tmu_init+0x28/0x34 > [ 2.163133] do_one_initcall+0x50/0x250 > [ 2.166979] kernel_init_freeable+0x278/0x31c > [ 2.171349] kernel_init+0x30/0x140 > [ 2.174847] ret_from_fork+0x10/0x20 > [ 2.178433] Code: b25657e2 d34cfc00 d37ae400 8b020015 (f94006a1) > [ 2.184546] ---[ end trace 0000000000000000 ]--- > > Store the allocated resource pointers before the thermal zone is free > and use them to release the resource after unregistering the thermal > zone. > > Reported-by: Michael Walle > Signed-off-by: Daniel Lezcano > --- > --- > drivers/thermal/thermal_of.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/thermal/thermal_of.c > b/drivers/thermal/thermal_of.c > index 4210c18ef7b2..91ffe8f90a2d 100644 > --- a/drivers/thermal/thermal_of.c > +++ b/drivers/thermal/thermal_of.c > @@ -596,11 +596,15 @@ static int thermal_of_unbind(struct > thermal_zone_device *tz, > */ > void thermal_of_zone_unregister(struct thermal_zone_device *tz) > { > + struct thermal_trip *trips = tz->trips; > + struct thermal_zone_params *tzp = tz->tzp; > + struct thermal_zone_device_ops *ops = tz->ops; > + git am shows a trailing whitespace here otherwise: Tested-by: Michael Walle (Yes, tested without the previous patches so the error actually happens ;)) -michael > thermal_zone_device_disable(tz); > thermal_zone_device_unregister(tz); > - kfree(tz->trips); > - kfree(tz->tzp); > - kfree(tz->ops); > + kfree(trips); > + kfree(tzp); > + kfree(ops); > } > EXPORT_SYMBOL_GPL(thermal_of_zone_unregister);