On Tue, 10 Oct 2017 19:24:11 +0000 <[email protected]> wrote:
> > -----Original Message----- > > From: Pali Rohár [mailto:[email protected]] > > Sent: Tuesday, October 10, 2017 2:12 PM > > To: Limonciello, Mario <[email protected]> > > Cc: [email protected]; Andy Shevchenko <[email protected]>; > > LKML <[email protected]>; [email protected]; > > Andy Lutomirski <[email protected]>; [email protected]; [email protected]; > > [email protected]; [email protected]; Greg KH <[email protected]> > > Subject: Re: [PATCH v6 13/14] platform/x86: wmi: create character devices > > when > > requested by drivers > > > > On Monday 09 October 2017 17:51:51 Mario Limonciello wrote: > > > + /* make sure we're not calling a higher instance than exists*/ > > > + if (_IOC_NR(cmd) > wblock->gblock.instance_count - 1) > > > + return -EINVAL; > > > > Is this condition really working? instance_count is unsigned, cmd is > > also unsigned... and when instance_count is zero, then IIRC error would > > not be thrown. > > > > But instance count can't be zero. MOF would fall apart with a zero instance > count. > If a broken BIOS was shipped with an instance count of zero bigger problems > would > have happened. Maybe but you can still write the test correctly using >= instead. Alan
