[PATCH nf-next 4/7] arptables: use match, target and data copy_to_user helpers

[Willem de Bruijn]

From: Willem de Bruijn <will...@google.com>

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 <will...@google.com>
---
 net/ipv4/netfilter/arp_tables.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index a467e12..6241a81 100644
--- 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;
                }
-- 
2.8.0.rc3.226.g39d4020