Re: [PATCH 8/8] modules: inherit TAINT_PROPRIETARY_MODULE

[Christoph Hellwig]

On Thu, Jul 30, 2020 at 04:12:32PM +0200, Jessica Yu wrote:
>> +	if (owner && test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints)) {
>> +		if (mod->using_gplonly_symbols) {
>> +			sym = NULL;
>> +			goto getname;
>> +		}
>> +		add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
>> +				 LOCKDEP_NOW_UNRELIABLE);
>> +	}
>
> Sorry that I didn't think of this yesterday, but I'm wondering if we
> should print a warning before add_taint_module(). Maybe something
> along the lines of, "%s: module uses symbols from proprietary module
> %s, inheriting taint.", with %s being mod->name, owner->name. We can
> check mod->taints for TAINT_PROPRIETARY_MODULE and print the warning once.
>
> Additionally, maybe it's a good idea to print an error before goto
> getname (e.g., "%s: module using GPL-only symbols uses symbols from
> proprietary module %s."), so one would know why the module load
> failed, right now this manifests itself as an unknown symbol error.
>
> Otherwise, this patchset looks good to me and I agree with it in
> principle. Thanks Christoph!

What about this version?  It also factors the code out into a new
helper, and replaces the add_taint_module with a simple set_bit,
as the system-wide tain must have been set before by definition:

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