netfilter: ebtables: fix alignment problem in ppc

ebt_among extension of ebtables uses __alignof__(_xt_align) while the
corresponding kernel module uses __alignof__(ebt_replace) to determine
the alignment in EBT_ALIGN().

These are the results of these values on different platforms:

x86 x86_64 ppc
__alignof__(_xt_align) 4 8 8
__alignof__(ebt_replace) 4 8 4

ebtables fails to add rules which use the among extension.

I'm using kernel 2.6.33 and ebtables 2.0.10-4

According to Bart De Schuymer, userspace alignment was changed to
_xt_align to fix an alignment issue on a userspace32-kernel64 system
(he thinks it was for an ARM device). So userspace must be right.
The kernel alignment macro needs to change so it also uses _xt_align
instead of ebt_replace. The userspace changes date back from
June 29, 2009.

Signed-off-by: Joerg Willmann <joe@clnt.de>
Signed-off by: Bart De Schuymer <bdschuym@pandora.be>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Joerg Willmann 2012-02-21 13:26:14 +01:00 коммит произвёл Pablo Neira Ayuso
Родитель a8db7b2d19
Коммит 88ba136d66
1 изменённых файлов: 2 добавлений и 2 удалений

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@ -285,8 +285,8 @@ struct ebt_table {
struct module *me;
};
#define EBT_ALIGN(s) (((s) + (__alignof__(struct ebt_replace)-1)) & \
~(__alignof__(struct ebt_replace)-1))
#define EBT_ALIGN(s) (((s) + (__alignof__(struct _xt_align)-1)) & \
~(__alignof__(struct _xt_align)-1))
extern struct ebt_table *ebt_register_table(struct net *net,
const struct ebt_table *table);
extern void ebt_unregister_table(struct net *net, struct ebt_table *table);