Re: [PATCH 0/2] power_supply: Fix Oops from NULL pointer dereferencefrom wakeup_source_activate

From: Anton Vorontsov
Date: Tue Nov 19 2013 - 16:11:31 EST


On Tue, Nov 19, 2013 at 08:59:34AM -0700, Shuah Khan wrote:
> power_supply_register() calls device_init_wakeup() to register a wakeup
> source before initializing dev_name. As a result, device_wakeup_enable()
> end up registering wakeup source with a null name when wakeup_source_register()
> gets called with dev_name(dev) which is null at the time.
>
> device_wakeup_enable() uses dev_name(dev) as the wakeup source name.
> When it gets called with a device with its name not yet set, ws structure
> with ws->name = NULL gets created.
>
> When kernel is booted with wakeup_source_activate enabled, it will panic
> when the trace point code tries to dereferences ws->name.
>
> This patch series fixes power_supply_register() to initialize the device name
> prior to calling device_init_wakeup() and adds WARN_ON on null device name to
> device_wakeup_enable() to detect driver bugs that result in calling
> device_wakeup_enable() before device is fully initialized with its name in
> device_wakeup_enable().
>
> It is important that these two fixes to be pulled in together as a series. The
> change to add WARN_ON on null device name without the power_supply_register()
> fix will result in early boot panics when AC Adapter and Battery device drivers
> try to register wakeup source.

I am all for it, so for the power_supply part:

Acked-by: Anton Vorontsov <anton@xxxxxxxxxx>
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