Re: iptables not working with monolithic 2.6.26.5 kernel on ARM

[Patrick McHardy <kaber@trash.net>]

Jan Engelhardt wrote:
> You can change the XT_ALIGN macro in the
> kernel/include/linux/netfilter/x_tables.h and
> iptables/include/linux/netfilter/x_tables.h to read
> 
> 	#ifndef roundup
> 	#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
> 	#endif
> 	#define XT_ALIGN(s) roundup(s, sizeof(uint64_t))
> 
> and try again. There might be more alignment issues hiding, so
> don't expect it to fix it all in a magic whizz.

An idea to avoid these problems in the future would be to change
the kernel so it accepts stricter alignment than what we currently
use and after a grace period (maybe 1-2 years) change XT_ALIGN in
userspace so it starts using u64 or simply 8 byte alignment
everywhere.