Subject: Re: [PATCH] genetlink: fix unsigned int comparison with less than zero

From: Johannes Berg <[email-masked]>
Date: Sat, 12 Nov 2016 22:37:16 +0100

On Thu, 2016-11-10 at 09:11 -0800, Cong Wang wrote:
> On Thu, Nov 10, 2016 at 7:57 AM, Colin King <[email-masked]
> > wrote:
> > 
> > From: Colin Ian King <[email-masked]>
> > 
> > family->id is unsigned, so the less than zero check for
> > failure return from idr_alloc is never true and so the error exit
> > is never handled.  Instead, assign err and check if this is less
> > than zero since this is a signed integer.
> 
> Why family->id can't be just signed int? For me it should be.

I suppose it could be, since family IDs are allocated in a 16-bit range
anyway. But family IDs can also never actually be negative, so having
an unsigned int in the struct makes sense too.

I tend to think this patch is fine.

johannes