Re: [PATCH 4.4 106/124] netlink: Do not subscribe to non-existent groups

From: Dmitry Safonov
Date: Sat Aug 04 2018 - 19:47:13 EST


On Sat, 2018-08-04 at 16:33 -0700, David Miller wrote:
> From: Dmitry Safonov <dima@xxxxxxxxxx>
> Date: Sun, 05 Aug 2018 00:26:38 +0100
>
> > Thanks for the testing, sorry again for the breakage.
> > Will send the patch shortly (with sizeof(unsigned long long)
> instead of
> > hard-coded 64). Hopefully, not too late.
>
> 'groups' is "long unsigned int" not "unsigned long long"
>
> long unsigned int groups = nladdr->nl_groups;
>
> And nladdr->nl_groups is specified as "__u32"
>
> So the size of the relevant bits is actually strictly 32-bit.
>
> This makes also the "ULL" in your constant specification incorrect as
> well.

I think, ULL is right - I did it to make shift for 32 well-defined.
(which in result has 32 bits set)

>
> So much crazy stuff going on here :-/