Subject: Re: [PATCH][next] net: ethernet: rmnet: Replace zero-length array with DECLARE_FLEX_ARRAY() helper

From: Jakub Kicinski <[email-masked]>
Date: Mon, 26 Sep 2022 17:26:04 -0700

On Mon, 26 Sep 2022 15:02:48 -0700 Kees Cook wrote:
> On Mon, Sep 26, 2022 at 04:50:03PM -0500, Gustavo A. R. Silva wrote:
> > Zero-length arrays are deprecated and we are moving towards adopting
> > C99 flexible-array members, instead. So, replace zero-length arrays
> > declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
> > helper macro.
> > 
> > This helper allows for flexible-array members in unions.
> > 
> > Link: https://github.com/KSPP/linux/issues/193
> > Link: https://github.com/KSPP/linux/issues/221
> > Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
> > Signed-off-by: Gustavo A. R. Silva <[email-masked]>  
> 
> Reviewed-by: Kees Cook <[email-masked]>

Not directly related to this patch, but I just had to look at pahole
output for sk_buff and the struct_group() stuff makes is really painful
to read :/ Offsets for the members are relative to the "group" and they
are all repeated.

Is there any chance you could fix that? Before we sprinkle more pixie
dust around, perhaps?