From patchwork Sat Jul 22 23:26:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13323066 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 356ECC001DC for ; Sat, 22 Jul 2023 23:27:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229651AbjGVX11 (ORCPT ); Sat, 22 Jul 2023 19:27:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229625AbjGVX10 (ORCPT ); Sat, 22 Jul 2023 19:27:26 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E9A819A6; Sat, 22 Jul 2023 16:27:25 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9B67A60BD8; Sat, 22 Jul 2023 23:27:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88B7FC433C8; Sat, 22 Jul 2023 23:27:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690068443; bh=C5VTDtOqdmj6Bz6JgxfHCEKJHYyIn7v2H/pyJ1qHGCM=; h=From:Date:Subject:To:Cc:From; b=fumBeebR/fj9xdn8EzaaqJ9QKok8wxdstGCw6EiJin3k5PiQAkG2KkNz6Gz1Ds0LN GDotCebW5AX3X2f+BFcvxqW1q1McAvTRUDK93mXtfZEIrLVfebrXeHyyjEb1ZyLFNv uyYNrjOx1HH8Tpx1X62ur6o/H9HLwIVllLVbCd1EsZTQ6KrV09RJGrn38NucQtDdgn 5mdHBKFRU9R1009c0gEAMfbpcl0aQ+t7hhD1xcygkiiaAXMoP5zAnSR5rNtXKGFgKN sWyuVPCRaJEvsu1UFB2vMYHFZIUDhb+AbpATIjlhnP429Ec8yeecDHpZcGQaDdrVNh cp/5igG+AETrA== From: Mark Brown Date: Sun, 23 Jul 2023 00:26:54 +0100 Subject: [PATCH] thermal/of: Fix double free of params during unregistration MIME-Version: 1.0 Message-Id: <20230723-thermal-fix-of-memory-corruption-v1-1-ed4fa16d199d@kernel.org> X-B4-Tracking: v=1; b=H4sIAL1lvGQC/x2N0QqDMAxFf0XybKBG0LFfGT64mtrAaiV1YyL+u 8HHA+eee0BhFS7wrA5Q/kmRvBg0dQU+jsvMKJMxkKPW9US4RdY0fjDIH3PAxCnrjj6rftfNxti 33tzw6Bp6g2VWZXPvi9dwnheUwZCCcgAAAA== To: "Rafael J. Wysocki" , Daniel Lezcano , Amit Kucheria , Zhang Rui Cc: Hugh Dickins , Will Deacon , Icenowy Zheng , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , linux-sunxi@lists.linux.dev, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Mark Brown , stable@vger.kernel.org X-Mailer: b4 0.13-dev-099c9 X-Developer-Signature: v=1; a=openpgp-sha256; l=2606; i=broonie@kernel.org; h=from:subject:message-id; bh=C5VTDtOqdmj6Bz6JgxfHCEKJHYyIn7v2H/pyJ1qHGCM=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBkvGXVA478VBnEpmpTCC3lkhtcVWQsWgJ581sVm 3BnS4HC/CyJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZLxl1QAKCRAk1otyXVSH 0JDuB/9a/lDjye3WC1siBtiAlqrJwcRmcgSVvUyChe5ZEPX/NPDNQV2sE4Y/pEBW9r7bEfVgWug tqEcqEuB5WtxrvMT6cCbg3BEFKMjy+JCJFExYChP5N6bJMwqicSzBsfF0YDBC5Th4H6pGTLP9u8 ZHlsg4d/3wYEVC/quGwLSSWgn3CulLd/rFDMzIMkYCc5y6XOChONE8A6Su5Bl+G03bQbY7AIEdL NS9IMolnTV9NYXaJImgQhjn1AhNHrCbosXp5PNQ6ya6ZK7B0OMWOB4Tee6EGDjJRuegJLqa4GhQ pu96tBHNv4NrjuxjnhnBtIPamTSl7r0Yh03594DCXVyhBFVf X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Unlike the other data structures provided during registration the thermal core takes a copy of the thermal_zone_params provided to it and stores that copy in the thermal_zone_device, taking care to free it on unregistration. This is done because the parameters will be modified at runtime. Unfortunately the thermal_of code assumes that the params structure it provides will be used throughout the lifetime of the device and since the params are dynamically allocated based on the bindings it attempts to free it on unregistration. This results in not only leaking the original params but also double freeing the copy the core made, leading to memory corruption. Fix this by instead freeing the params parsed from the DT during registration. This issue causing instability on systems where thermal zones are unregistered, especially visble on those systems where some zones provided by a device have no trip points such as Allwinner systems. For example with current mainline an arm64 defconfig is unbootable on Pine64 Plus and LibreTech Tritium is massively unstable. These issues have been there for a while and have been made more prominent by recent memory management changes. Fixes: 3fd6d6e2b4e80 ("thermal/of: Rework the thermal device tree initialization") Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/thermal/thermal_of.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- base-commit: fdf0eaf11452d72945af31804e2a1048ee1b574c change-id: 20230722-thermal-fix-of-memory-corruption-73c023f8612b Best regards, diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c index 6fb14e521197..0af11cdfa2c1 100644 --- a/drivers/thermal/thermal_of.c +++ b/drivers/thermal/thermal_of.c @@ -442,13 +442,11 @@ static int thermal_of_unbind(struct thermal_zone_device *tz, static 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; thermal_zone_device_disable(tz); thermal_zone_device_unregister(tz); kfree(trips); - kfree(tzp); kfree(ops); } @@ -530,6 +528,9 @@ static struct thermal_zone_device *thermal_of_zone_register(struct device_node * goto out_kfree_tzp; } + /* The core will take a copy of tzp, free our copy here. */ + kfree(tzp); + ret = thermal_zone_device_enable(tz); if (ret) { pr_err("Failed to enabled thermal zone '%s', id=%d: %d\n",