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,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 5DF67C433E9 for ; Thu, 25 Mar 2021 11:31:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 23BCC61A58 for ; Thu, 25 Mar 2021 11:31:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231727AbhCYLbb (ORCPT ); Thu, 25 Mar 2021 07:31:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:35542 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230163AbhCYL0j (ORCPT ); Thu, 25 Mar 2021 07:26:39 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4206761A4A; Thu, 25 Mar 2021 11:26:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616671598; bh=0PspNJECVDrJESPZ4603uo9HjeciJGkf37foAb3OEAk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KUUMSn5dQ26YeNenncGtnfbit9PfuiY03UHrX2TfKphn4IZ5Xc15r/H31pI2wS2gC TnM5dJFFXV2Gbv9OOjeeQyQyeCjOnjEwtbuCR5yVm4bLvkhkf4Pc3XolfhAwNczCx9 T43fQ2etOeHcdAXlSXX53MCHKh+SAe9LB5fkiiSniaPX0SqzNahvQ9dWFP4ZHXYI// NOiHwxx1N1ZQXj68otVTe4GQgX3xxZu9qB6d7f1ckjw1FgbiymJ/yEee1oEwtyz3Px rLSq2gsQo3zpuMTXtZSex3lh3aFdQog/1AFA9r92Eni7rBnrJKrQnTcQ5kOXEGV3iU G8JONW01qP6Vg== 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 5.10 30/39] thermal/core: Add NULL pointer check before using cooling device stats Date: Thu, 25 Mar 2021 07:25:49 -0400 Message-Id: <20210325112558.1927423-30-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210325112558.1927423-1-sashal@kernel.org> References: <20210325112558.1927423-1-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 a6f371fc9af2..f52708f310e0 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