Subject: Re: [PATCH 1/3] wlcore/wl12xx: spi: fix NULL pointer dereference
 (Oops)
To: Grygorii Strashko <grygorii.strashko@ti.com>,
	Kalle Valo <kvalo@codeaurora.org>,
	Rob Herring <robh+dt@kernel.org>,
	Tony Lindgren <tony@atomide.com>
References: <1450859744-9948-1-git-send-email-uri.mashiach@compulab.co.il>
 <1450859744-9948-2-git-send-email-uri.mashiach@compulab.co.il>
 <567A7287.3010205@ti.com>
Cc: Pawel Moll <pawel.moll@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Ian Campbell <ijc+devicetree@hellion.org.uk>,
	Kumar Gala <galak@codeaurora.org>, bcousson@baylibre.com,
	Igor Grinberg <grinberg@compulab.co.il>,
	Eliad Peller <eliad@wizery.com>, devicetree@vger.kernel.org,
	linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-wireless@vger.kernel.org
From: Uri Mashiach <uri.mashiach@compulab.co.il>
Message-ID: <567AAB89.4010101@compulab.co.il> (sfid-20151223_151135_767017_71BCDD38)
Date: Wed, 23 Dec 2015 16:11:21 +0200
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In-Reply-To: <567A7287.3010205@ti.com>
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Sender: linux-wireless-owner@vger.kernel.org

Hi Grygorii,

On 12/23/2015 12:08 PM, Grygorii Strashko wrote:
> On 12/23/2015 10:35 AM, Uri Mashiach wrote:
>> The power function uses a consumer regulator access to update the WiFi
>> enable GPIO value.
>>
>> Fix the below Oops when trying to modprobe wlcore_spi.
>> The oops occurs because the wl1271_power_{off,on}()
>> function doesn't check the power() function pointer.
>>
>> [   23.401447] Unable to handle kernel NULL pointer dereference at
>> virtual address 00000000
>> [   23.409954] pgd = c0004000
>> [   23.412922] [00000000] *pgd=00000000
>> [   23.416693] Internal error: Oops: 80000007 [#1] SMP ARM
>> [   23.422168] Modules linked in: wl12xx wlcore mac80211 cfg80211
>> musb_dsps musb_hdrc usbcore usb_common snd_soc_simple_card evdev joydev
>> omap_rng wlcore_spi snd_soc_tlv320aic23_i2c rng_core snd_soc_tlv320aic23
>> c_can_platform c_can can_dev snd_soc_davinci_mcasp snd_soc_edma
>> snd_soc_omap omap_wdt musb_am335x cpufreq_dt thermal_sys hwmon
>> [   23.453253] CPU: 0 PID: 36 Comm: kworker/0:2 Not tainted
>> 4.2.0-00002-g951efee-dirty #233
>> [   23.461720] Hardware name: Generic AM33XX (Flattened Device Tree)
>> [   23.468123] Workqueue: events request_firmware_work_func
>> [   23.473690] task: de32efc0 ti: de4ee000 task.ti: de4ee000
>> [   23.479341] PC is at 0x0
>> [   23.482112] LR is at wl12xx_set_power_on+0x28/0x124 [wlcore]
>
> Why can't you just add proper check in wl1271_power_on/wl1271_power_off() instead?
>

Will be done in v2.

Thanks,
Uri