arptables: use match, target and data copy_to_user helpers

Convert arptables to copying entries, matches and targets one by one,
using the xt_match_to_user and xt_target_to_user helper functions.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index a467e1236c43ed1f3ecaa55524eb59722f1682e8..6241a81fd7f5a3df8fb3cf251bfdd407dda6a1f6 100644 (file)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -677,11 +677,6 @@ static int copy_entries_to_user(unsigned int total_size,
                return PTR_ERR(counters);
 
        loc_cpu_entry = private->entries;
-       /* ... then copy entire thing ... */
-       if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) {
-               ret = -EFAULT;
-               goto free_counters;
-       }
 
        /* FIXME: use iterator macros --RR */
        /* ... then go back and fix counters and names */
@@ -689,6 +684,10 @@ static int copy_entries_to_user(unsigned int total_size,
                const struct xt_entry_target *t;
 
                e = (struct arpt_entry *)(loc_cpu_entry + off);
+               if (copy_to_user(userptr + off, e, sizeof(*e))) {
+                       ret = -EFAULT;
+                       goto free_counters;
+               }
                if (copy_to_user(userptr + off
                                 + offsetof(struct arpt_entry, counters),
                                 &counters[num],
@@ -698,11 +697,7 @@ static int copy_entries_to_user(unsigned int total_size,
                }
 
                t = arpt_get_target_c(e);
-               if (copy_to_user(userptr + off + e->target_offset
-                                + offsetof(struct xt_entry_target,
-                                           u.user.name),
-                                t->u.kernel.target->name,
-                                strlen(t->u.kernel.target->name)+1) != 0) {
+               if (xt_target_to_user(t, userptr + off + e->target_offset)) {
                        ret = -EFAULT;
                        goto free_counters;
                }