Re: [PATCH v7 10/15] platform/x86: dell-smbios: add filtering capability for requests

[Alan Cox]

> I think I'd actually like to meld this with your other ideas and what I've 
> currently got.  What do you think of this approach:
> 
> 	/* kernel community doesn't feel userspace should have access at all
> 	  * or other kernel drivers use this
> 	  */
> 	if (blacklisted)
> 		return NO;
> 
> 	/* unprivileged access allowed */
>  	if (whitelisted & (capabilities && whitelist->capability_need) ==
>  	whitelist->capability_need))
>  		return ALLOWED;
>  
> 	/* not yet in whitelist, or need privs to do */
>  	if (capable(CAP_SYS_RAWIO))
>  		return ALLOWED;
>  
>  	return NO
> 

This looks sensible to me. Note that the middle case isn't necessarily
'unprviliged'. If the entyr is whitelisted and the capability_need is 0
then it means 'anyone' but you can also set any other appropriate
capability (eg CAP_NET_ADMIN for a WMI call that does stuff to the wifi).

Alan