ipt_error_target in kernel difers from that in user space and causing "ip_tables: ERROR target: invalid size 30 != 32"

["David Wu" <davidwu@arcturusnetworks.com>]

Hello all,

I came across this problem when runing iptables-1.3.7 on 2.6.19 and 2.6.20  
kernel(MCF5329):
   ip_tables: ERROR target: invalid size 30 != 32
which comes from:
        xt_check_target() (net/netfilter/x_tables.c)

        if (XT_ALIGN(target->targetsize) != size) {
                printk("%s_tables: %s target: invalid size %Zu != %u\n",
                       xt_prefix[family], target->name,
                       XT_ALIGN(target->targetsize), size);
                return -EINVAL;
        }

I noticed that in libiptc/libiptc.c(iptables-1.3.7) ipt_error_target is  
defined as:
   struct ipt_error_target
   {
        STRUCT_ENTRY_TARGET t;
        char error[TABLE_MAXNAMELEN];
   };

while in the kernel it defined as:
   struct ipt_error_target
   {
        struct ipt_entry_target target;
        char errorname[IPT_FUNCTION_MAXNAMELEN];
   };

in net/ipv4/netfilter/ip_tables.c there is another:
   static struct ipt_target ipt_error_target = {
        .name           = IPT_ERROR_TARGET,
        .target         = ipt_error,
        .targetsize     = IPT_FUNCTION_MAXNAMELEN,
        .family         = AF_INET,
   };

TABLE_MAXNAMELEN and IPT_FUNCTION_MAXNAMELEN are not equal!!!

Is this a bug? Who can tell me which one is correct?

thanks,

--
David
davidwu@arcturusnetworks.com