Re: [PATCH V2 3/6] mpcore_wdt: Fix WDIOC_SETOPTIONS handling

Vitaly Kuzmichev
2011-07-06T13:15:37Z

Hi Arnd,

On 07/06/2011 04:22 PM, Arnd Bergmann wrote:
> On Tuesday 05 July 2011, Vitaly Kuzmichev wrote:
>>
>> According to the include/linux/watchdog.h WDIOC_SETOPTIONS is
>> classified as 'read from device' ioctl call:
>> #define WDIOC_SETOPTIONS _IOR(WATCHDOG_IOCTL_BASE, 4, int)
>>
>> However, the driver 'mpcore_wdt' performs 'copy_from_user' only if
>> _IOC_WRITE is set, thus the local variable 'uarg' which is used in
>> WDIOC_SETOPTIONS handling remains uninitialized.
>>
>> The proper way to fix this is to bind WDIOC_SETOPTIONS to _IOW,
>> but this will break compatibility.
>> So adding additional condition for performing 'copy_from_user'.
>>
>> Signed-off-by: Vitaly Kuzmichev <vkuzmichev@mvista.com>
>
> Is the new watchdog driver core ready for 3.1? If so, the best
> solution would be to get rid of the entire ioctl function in
> the mpcore_wdt driver and just use the core for that.

In this case the whole mpcore_wdt driver should be rewritten.
And then this should be done in a separate set of patches, I think.
And this may take more time than is seems now.
So I would keep this patch.

Thanks,
Vitaly.