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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 32510C433EA for ; Thu, 25 Mar 2021 11:35:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A0C661A2E for ; Thu, 25 Mar 2021 11:35:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231895AbhCYLfM (ORCPT ); Thu, 25 Mar 2021 07:35:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:35442 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230101AbhCYL3O (ORCPT ); Thu, 25 Mar 2021 07:29:14 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2E75161A3F; Thu, 25 Mar 2021 11:27:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616671640; bh=NbXGtagGC6nta9wmmqR4lJoh5XClR+lCZLLHV+MV860=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Pz89Xfrx8Pl7E5PmtOFfAFGFU0Z1Ogn5l1j77ffrJQ37X9HtuadBD4MaTEc9GRi2G 6gObv07gBXqQzvP8LVOWCAjqYue9++6KAwKbTmeH5rOMpqs3tX8dvYZqTMv9derAzw vnsorl8pARXsBaFx5jKxM2gA2UgW8s28jA1Qrmzc9cwy8mTl5kTWhfQpvpcRXLl6TA hoO48ojtAhUHruNEwVnJV9Y2XnLuOnQXRMraTWie7+OUvS5zD+kHIJCVIyF7ZWwvnB k3igS9ZcZspecMmx6n/3FiUuTthFwNKMYliO/V97vADHWwQpUrPypk7rJMLzw1hs+O 0GYpS/53pwlsQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Manaf Meethalavalappu Pallikunhi , Daniel Lezcano , Sasha Levin , linux-pm@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 22/24] thermal/core: Add NULL pointer check before using cooling device stats Date: Thu, 25 Mar 2021 07:26:48 -0400 Message-Id: <20210325112651.1927828-22-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210325112651.1927828-1-sashal@kernel.org> References: <20210325112651.1927828-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Manaf Meethalavalappu Pallikunhi [ Upstream commit 2046a24ae121cd107929655a6aaf3b8c5beea01f ] There is a possible chance that some cooling device stats buffer allocation fails due to very high cooling device max state value. Later cooling device update sysfs can try to access stats data for the same cooling device. It will lead to NULL pointer dereference issue. Add a NULL pointer check before accessing thermal cooling device stats data. It fixes the following bug [ 26.812833] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 [ 27.122960] Call trace: [ 27.122963] do_raw_spin_lock+0x18/0xe8 [ 27.122966] _raw_spin_lock+0x24/0x30 [ 27.128157] thermal_cooling_device_stats_update+0x24/0x98 [ 27.128162] cur_state_store+0x88/0xb8 [ 27.128166] dev_attr_store+0x40/0x58 [ 27.128169] sysfs_kf_write+0x50/0x68 [ 27.133358] kernfs_fop_write+0x12c/0x1c8 [ 27.133362] __vfs_write+0x54/0x160 [ 27.152297] vfs_write+0xcc/0x188 [ 27.157132] ksys_write+0x78/0x108 [ 27.162050] ksys_write+0xf8/0x108 [ 27.166968] __arm_smccc_hvc+0x158/0x4b0 [ 27.166973] __arm_smccc_hvc+0x9c/0x4b0 [ 27.186005] el0_svc+0x8/0xc Signed-off-by: Manaf Meethalavalappu Pallikunhi Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/1607367181-24589-1-git-send-email-manafm@codeaurora.org Signed-off-by: Sasha Levin --- drivers/thermal/thermal_sysfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c index aa99edb4dff7..4dce4a8f71ed 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -770,6 +770,9 @@ void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev, { struct cooling_dev_stats *stats = cdev->stats; + if (!stats) + return; + spin_lock(&stats->lock); if (stats->state == new_state) -- 2.30.1