From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754713AbbBTNdG (ORCPT ); Fri, 20 Feb 2015 08:33:06 -0500 Received: from mailout2.w1.samsung.com ([210.118.77.12]:57580 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754442AbbBTNch (ORCPT ); Fri, 20 Feb 2015 08:32:37 -0500 X-AuditID: cbfec7f4-b7f126d000001e9a-da-54e736e17b4e From: Krzysztof Kozlowski To: Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse , Milo Kim , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dmitry Artamonow , Marek Belisko , Krzysztof Kozlowski , stable@vger.kernel.org Subject: [RFT RESEND 3/4] power_supply: ipaq_micro_battery: Check return values in probe Date: Fri, 20 Feb 2015 14:32:24 +0100 Message-id: <1424439145-16895-3-git-send-email-k.kozlowski@samsung.com> X-Mailer: git-send-email 1.9.1 In-reply-to: <1424439145-16895-1-git-send-email-k.kozlowski@samsung.com> References: <1424439145-16895-1-git-send-email-k.kozlowski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprELMWRmVeSWpSXmKPExsVy+t/xq7oPzZ6HGHx8wWMx6cl7ZouJKycz W7x+YWhxedccNovPvUcYLba3HWWx+Ld0C5vF8l/rWCxO7y6xWLDxEaMDl8fOWXfZPda8P8Xs cezaHRaPzSu0PDat6mTz6NuyitHj+I3tTB6fN8kFcERx2aSk5mSWpRbp2yVwZVw8yV6wXahi 9r4/bA2Mx/m7GDk5JARMJF7ebGeEsMUkLtxbz9bFyMUhJLCUUeJgay8ThNPHJNG19RsbSBWb gLHE5uVLwKpEBK4zSlx5eQysillgGqPE1ScrwKqEBaIkVv47ADaXRUBV4uuUT2A2r4C7xK2P /6H2yUmcPDaZFcTmFPCQ6Nw2F8wWAqpZ9nQd0wRG3gWMDKsYRVNLkwuKk9JzDfWKE3OLS/PS 9ZLzczcxQsLxyw7GxcesDjEKcDAq8fD+2PMsRIg1say4MvcQowQHs5IIr6fC8xAh3pTEyqrU ovz4otKc1OJDjEwcnFINjN7xqfzP/d1vVlgVRUmG/zwvKO/0ymSvuVa+ndg6q/mbq7Y1+l1+ u3MnYz73TeGIFTN6rY8oPHnfyhlR57mf7WLr2TOtypyXjBjmHMs1ClwjaHP9G3tc16LQ+P8J zWIrZxt0PjBLvuCcx1I5+9KMfbnrzkk/NAqyzWXj+b9DTdr05cZz16yuKrEUZyQaajEXFScC ALLtc8QlAgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The return values of create_singlethread_workqueue() and power_supply_register() calls were not checked and even on error probe() function returned 0. 1. If allocation of workqueue failed (returning NULL) then further accesses could lead to NULL pointer dereference. The queue_delayed_work() expects workqueue to be non-NULL. 2. If registration of power supply failed then during unbind the driver tried to unregister power supply which was not actually registered. This could lead to memory corruption because power_supply_unregister() unconditionally cleans up given power supply. Signed-off-by: Krzysztof Kozlowski Fixes: 00a588f9d27f ("power: add driver for battery reading on iPaq h3xxx") Cc: --- drivers/power/ipaq_micro_battery.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/power/ipaq_micro_battery.c b/drivers/power/ipaq_micro_battery.c index 698cf1636bb8..96b15e003f3f 100644 --- a/drivers/power/ipaq_micro_battery.c +++ b/drivers/power/ipaq_micro_battery.c @@ -226,6 +226,7 @@ static struct power_supply micro_ac_power = { static int micro_batt_probe(struct platform_device *pdev) { struct micro_battery *mb; + int ret; mb = devm_kzalloc(&pdev->dev, sizeof(*mb), GFP_KERNEL); if (!mb) @@ -233,14 +234,30 @@ static int micro_batt_probe(struct platform_device *pdev) mb->micro = dev_get_drvdata(pdev->dev.parent); mb->wq = create_singlethread_workqueue("ipaq-battery-wq"); + if (!mb->wq) + return -ENOMEM; + INIT_DELAYED_WORK(&mb->update, micro_battery_work); platform_set_drvdata(pdev, mb); queue_delayed_work(mb->wq, &mb->update, 1); - power_supply_register(&pdev->dev, µ_batt_power); - power_supply_register(&pdev->dev, µ_ac_power); + + ret = power_supply_register(&pdev->dev, µ_batt_power); + if (ret < 0) + goto batt_err; + + ret = power_supply_register(&pdev->dev, µ_ac_power); + if (ret < 0) + goto ac_err; dev_info(&pdev->dev, "iPAQ micro battery driver\n"); return 0; + +ac_err: + power_supply_unregister(µ_ac_power); +batt_err: + cancel_delayed_work_sync(&mb->update); + destroy_workqueue(mb->wq); + return ret; } static int micro_batt_remove(struct platform_device *pdev) -- 1.9.1