Re: Wrapping EXPORT_SYMBOL_GPL symbols and re-exporting the wrappers with EXPORT_SYMBOL

From: BjÃrn Mork
Date: Tue Jul 02 2013 - 04:47:49 EST


richard -rw- weinberger <richard.weinberger@xxxxxxxxx> writes:
> On Mon, Jul 1, 2013 at 11:38 PM, Borislav Petkov <bp@xxxxxxxxx> wrote:
>> On Mon, Jul 01, 2013 at 03:32:27PM +0200, BjÃrn Mork wrote:
>>> I just got a new wireless router and stumbled across an odd set of
>>> out-of-tree modules, where two GPL licensed modules were used by a third
>>> proprietary licensed one.
>>>
>>> The nice router vendor sent me the GPL'd source code, and as expected
>>> the GPL modules are little more than wrappers working around the
>>> EXPORT_SYMBOL_GPL restrictions. Here's a complete example of one of
>>> them:
>>
>> I'm wondering if we could fail building modules which do EXPORT_SYMBOL.
>
> Then vendors will do a s/EXPORT_SYMBOL_GPL/EXPORT_SYMBOL/g on the kernel.
> Recently I've identified such a case.

Well, in this particular case I don't think that would happen. I
believe the router vendor is actually trying their best to comply with
the GPL. They have a well documented and working way to request full
source, and the source I received seems complete and matching the latest
firmware version (as requested).

I believe they are unware of this issue in a minor software component
they have obviously bought from a 3rd party, sold as a SDK with a few
standalone kernel modules . I do believe the router vendor would have
refused if this software required any modifications to the kernel. I
believe the same goes for the SoC vendor which of course is responsible
for most of the firmware, including the kernel.

> BjÃrn, please post this on legal@xxxxxxxxxxxxxxxxxxxxxxxx too.

Done.



BjÃrn
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