Re: [PATCH] uapi/netfilter: Prefer ISO-friendly __typeof__

From: Petr Vorel
Date: Mon Apr 24 2023 - 12:48:31 EST


> On 16/04/2023 23:07, Petr Vorel wrote:
> > typeof() is a GNU extension, UAPI requires ISO C, therefore __typeof__()
> > should be used. Similarly to b4bd35a19df5 ("uapi/linux/const.h: Prefer
> > ISO-friendly __typeof__") use __typeof__() also in x_tables.h.

> Thanks for finishing up the work!

> Minor thing, the hash for my commit in -next seems to be 31088f6f7906 at
> the moment. As to the Fixes: tag, it looks like it should be (assuming
> that commit already exported the macro):

> Fixes: 72b2b1dd77e8 ("netfilter: xtables: replace XT_ENTRY_ITERATE macro")

> Aside from that, looks good to me, so:

Thank you!

Andrew, I'll just wait for others to comment and then I'll send v2
(so that you don't need to update the work yourself).

Kind regards,
Petr

> Reviewed-by: Kevin Brodsky <kevin.brodsky@xxxxxxx>

> Kevin

> > Signed-off-by: Petr Vorel <pvorel@xxxxxxx>
> > ---
> > Based on [1] merged into linux-next as b4bd35a19df5.
> > There should be the same Fixes: which we agree in discussion in [1]
> > (likely a79ff731a1b2, or d6fc9fcbaa65).

> > Kind regards,
> > Petr

> > [1] https://lore.kernel.org/lkml/20230411092747.3759032-1-kevin.brodsky@xxxxxxx/


> > include/uapi/linux/netfilter/x_tables.h | 8 ++++----
> > 1 file changed, 4 insertions(+), 4 deletions(-)

> > diff --git a/include/uapi/linux/netfilter/x_tables.h b/include/uapi/linux/netfilter/x_tables.h
> > index 796af83a963a..d4eced07f2a2 100644
> > --- a/include/uapi/linux/netfilter/x_tables.h
> > +++ b/include/uapi/linux/netfilter/x_tables.h
> > @@ -172,11 +172,11 @@ struct xt_counters_info {

> > /* pos is normally a struct ipt_entry/ip6t_entry/etc. */
> > #define xt_entry_foreach(pos, ehead, esize) \
> > - for ((pos) = (typeof(pos))(ehead); \
> > - (pos) < (typeof(pos))((char *)(ehead) + (esize)); \
> > - (pos) = (typeof(pos))((char *)(pos) + (pos)->next_offset))
> > + for ((pos) = (__typeof__(pos))(ehead); \
> > + (pos) < (__typeof__(pos))((char *)(ehead) + (esize)); \
> > + (pos) = (__typeof__(pos))((char *)(pos) + (pos)->next_offset))

> > -/* can only be xt_entry_match, so no use of typeof here */
> > +/* can only be xt_entry_match, so no use of __typeof__ here */
> > #define xt_ematch_foreach(pos, entry) \
> > for ((pos) = (struct xt_entry_match *)entry->elems; \
> > (pos) < (struct xt_entry_match *)((char *)(entry) + \