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 1CC36C4345E for ; Thu, 25 Mar 2021 11:28:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F085161A78 for ; Thu, 25 Mar 2021 11:28:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231607AbhCYL2I (ORCPT ); Thu, 25 Mar 2021 07:28:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:34116 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230306AbhCYLZn (ORCPT ); Thu, 25 Mar 2021 07:25:43 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 26C4861A24; Thu, 25 Mar 2021 11:25:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616671542; bh=ym85RzS/JUtaS267Olck5OzQXWkc+gY0qQ3k0DdlQ2E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FtqfueUNe5XnLDLrBq3FXrJkEmDi719RaaNs1OnjcSgiGhm6GSxj0ajyoiYi72EUG FU1BsZl6xyEIe+dS/zpgUDOjnAxvvnXQfzYptaEEVuRcPMlijXImI6qvcuoFpUfpXc E/RTn+dHteMON9aHTS9hzmvw+Xfdghq0cbaLay0cxYl+grDyRjMP1vuW/V/OYlrDJT vFEfvKEKUeTbzLTE6twfJQujKq7Pj8t04V5KUsG56mUqElUJrqNISxEp0k6lqphHSJ E/U1MwJ8emaVFadUUiKyrW453DhHZ+F7CfFKfV5lJWCSR746skdDqGreDHR+6oO/KZ RUeDpgHhm0l7A== 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 5.11 33/44] thermal/core: Add NULL pointer check before using cooling device stats Date: Thu, 25 Mar 2021 07:24:48 -0400 Message-Id: <20210325112459.1926846-33-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210325112459.1926846-1-sashal@kernel.org> References: <20210325112459.1926846-1-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 0866e949339b..9b73532464e5 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -754,6 +754,9 @@ 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