[NETFILTER]: arp_tables: add compat support
authorPatrick McHardy <kaber@trash.net>
Tue, 18 Dec 2007 06:26:54 +0000 (22:26 -0800)
committerDavid S. Miller <davem@davemloft.net>
Mon, 28 Jan 2008 22:58:49 +0000 (14:58 -0800)
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/linux/netfilter_arp/arp_tables.h
net/ipv4/netfilter/arp_tables.c

index 7ade26b..53dd4df 100644 (file)
@@ -281,5 +281,36 @@ extern unsigned int arpt_do_table(struct sk_buff *skb,
                                  struct arpt_table *table);
 
 #define ARPT_ALIGN(s) XT_ALIGN(s)
+
+#ifdef CONFIG_COMPAT
+#include <net/compat.h>
+
+struct compat_arpt_entry
+{
+       struct arpt_arp arp;
+       u_int16_t target_offset;
+       u_int16_t next_offset;
+       compat_uint_t comefrom;
+       struct compat_xt_counters counters;
+       unsigned char elems[0];
+};
+
+static inline struct arpt_entry_target *
+compat_arpt_get_target(struct compat_arpt_entry *e)
+{
+       return (void *)e + e->target_offset;
+}
+
+#define COMPAT_ARPT_ALIGN(s)   COMPAT_XT_ALIGN(s)
+
+/* fn returns 0 to continue iteration */
+#define COMPAT_ARPT_ENTRY_ITERATE(entries, size, fn, args...) \
+       XT_ENTRY_ITERATE(struct compat_arpt_entry, entries, size, fn, ## args)
+
+#define COMPAT_ARPT_ENTRY_ITERATE_CONTINUE(entries, size, n, fn, args...) \
+       XT_ENTRY_ITERATE_CONTINUE(struct compat_arpt_entry, entries, size, n, \
+                                 fn, ## args)
+
+#endif /* CONFIG_COMPAT */
 #endif /*__KERNEL__*/
 #endif /* _ARPTABLES_H */
index 029df76..ad2da6d 100644 (file)
 #include <linux/proc_fs.h>
 #include <linux/module.h>
 #include <linux/init.h>
-
-#include <asm/uaccess.h>
 #include <linux/mutex.h>
+#include <linux/err.h>
+#include <net/compat.h>
+#include <asm/uaccess.h>
 
 #include <linux/netfilter/x_tables.h>
 #include <linux/netfilter_arp/arp_tables.h>
@@ -782,7 +783,73 @@ static int copy_entries_to_user(unsigned int total_size,
        return ret;
 }
 
-static int get_info(void __user *user, int *len)
+#ifdef CONFIG_COMPAT
+static void compat_standard_from_user(void *dst, void *src)
+{
+       int v = *(compat_int_t *)src;
+
+       if (v > 0)
+               v += xt_compat_calc_jump(NF_ARP, v);
+       memcpy(dst, &v, sizeof(v));
+}
+
+static int compat_standard_to_user(void __user *dst, void *src)
+{
+       compat_int_t cv = *(int *)src;
+
+       if (cv > 0)
+               cv -= xt_compat_calc_jump(NF_ARP, cv);
+       return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
+}
+
+static int compat_calc_entry(struct arpt_entry *e,
+                            const struct xt_table_info *info,
+                            void *base, struct xt_table_info *newinfo)
+{
+       struct arpt_entry_target *t;
+       unsigned int entry_offset;
+       int off, i, ret;
+
+       off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
+       entry_offset = (void *)e - base;
+
+       t = arpt_get_target(e);
+       off += xt_compat_target_offset(t->u.kernel.target);
+       newinfo->size -= off;
+       ret = xt_compat_add_offset(NF_ARP, entry_offset, off);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
+               if (info->hook_entry[i] &&
+                   (e < (struct arpt_entry *)(base + info->hook_entry[i])))
+                       newinfo->hook_entry[i] -= off;
+               if (info->underflow[i] &&
+                   (e < (struct arpt_entry *)(base + info->underflow[i])))
+                       newinfo->underflow[i] -= off;
+       }
+       return 0;
+}
+
+static int compat_table_info(const struct xt_table_info *info,
+                            struct xt_table_info *newinfo)
+{
+       void *loc_cpu_entry;
+
+       if (!newinfo || !info)
+               return -EINVAL;
+
+       /* we dont care about newinfo->entries[] */
+       memcpy(newinfo, info, offsetof(struct xt_table_info, entries));
+       newinfo->initial_entries = 0;
+       loc_cpu_entry = info->entries[raw_smp_processor_id()];
+       return ARPT_ENTRY_ITERATE(loc_cpu_entry, info->size,
+                                 compat_calc_entry, info, loc_cpu_entry,
+                                 newinfo);
+}
+#endif
+
+static int get_info(void __user *user, int *len, int compat)
 {
        char name[ARPT_TABLE_MAXNAMELEN];
        struct arpt_table *t;
@@ -798,13 +865,24 @@ static int get_info(void __user *user, int *len)
                return -EFAULT;
 
        name[ARPT_TABLE_MAXNAMELEN-1] = '\0';
-
+#ifdef CONFIG_COMPAT
+       if (compat)
+               xt_compat_lock(NF_ARP);
+#endif
        t = try_then_request_module(xt_find_table_lock(NF_ARP, name),
                                    "arptable_%s", name);
        if (t && !IS_ERR(t)) {
                struct arpt_getinfo info;
                struct xt_table_info *private = t->private;
 
+#ifdef CONFIG_COMPAT
+               if (compat) {
+                       struct xt_table_info tmp;
+                       ret = compat_table_info(private, &tmp);
+                       xt_compat_flush_offsets(NF_ARP);
+                       private = &tmp;
+               }
+#endif
                info.valid_hooks = t->valid_hooks;
                memcpy(info.hook_entry, private->hook_entry,
                       sizeof(info.hook_entry));
@@ -822,6 +900,10 @@ static int get_info(void __user *user, int *len)
                module_put(t->me);
        } else
                ret = t ? PTR_ERR(t) : -ENOENT;
+#ifdef CONFIG_COMPAT
+       if (compat)
+               xt_compat_unlock(NF_ARP);
+#endif
        return ret;
 }
 
@@ -864,65 +946,41 @@ static int get_entries(struct arpt_get_entries __user *uptr, int *len)
        return ret;
 }
 
-static int do_replace(void __user *user, unsigned int len)
+static int __do_replace(const char *name, unsigned int valid_hooks,
+                       struct xt_table_info *newinfo,
+                       unsigned int num_counters,
+                       void __user *counters_ptr)
 {
        int ret;
-       struct arpt_replace tmp;
        struct arpt_table *t;
-       struct xt_table_info *newinfo, *oldinfo;
+       struct xt_table_info *oldinfo;
        struct xt_counters *counters;
-       void *loc_cpu_entry, *loc_cpu_old_entry;
-
-       if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
-               return -EFAULT;
-
-       /* overflow check */
-       if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
-               return -ENOMEM;
-
-       newinfo = xt_alloc_table_info(tmp.size);
-       if (!newinfo)
-               return -ENOMEM;
+       void *loc_cpu_old_entry;
 
-       /* choose the copy that is on our node/cpu */
-       loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
-       if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
-                          tmp.size) != 0) {
-               ret = -EFAULT;
-               goto free_newinfo;
-       }
-
-       counters = vmalloc_node(tmp.num_counters * sizeof(struct xt_counters),
+       ret = 0;
+       counters = vmalloc_node(num_counters * sizeof(struct xt_counters),
                                numa_node_id());
        if (!counters) {
                ret = -ENOMEM;
-               goto free_newinfo;
+               goto out;
        }
 
-       ret = translate_table(tmp.name, tmp.valid_hooks,
-                             newinfo, loc_cpu_entry, tmp.size, tmp.num_entries,
-                             tmp.hook_entry, tmp.underflow);
-       if (ret != 0)
-               goto free_newinfo_counters;
-
-       duprintf("arp_tables: Translated table\n");
-
-       t = try_then_request_module(xt_find_table_lock(NF_ARP, tmp.name),
-                                   "arptable_%s", tmp.name);
+       t = try_then_request_module(xt_find_table_lock(NF_ARP, name),
+                                   "arptable_%s", name);
        if (!t || IS_ERR(t)) {
                ret = t ? PTR_ERR(t) : -ENOENT;
                goto free_newinfo_counters_untrans;
        }
 
        /* You lied! */
-       if (tmp.valid_hooks != t->valid_hooks) {
+       if (valid_hooks != t->valid_hooks) {
                duprintf("Valid hook crap: %08X vs %08X\n",
-                        tmp.valid_hooks, t->valid_hooks);
+                        valid_hooks, t->valid_hooks);
                ret = -EINVAL;
                goto put_module;
        }
 
-       oldinfo = xt_replace_table(t, tmp.num_counters, newinfo, &ret);
+       oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
        if (!oldinfo)
                goto put_module;
 
@@ -940,11 +998,12 @@ static int do_replace(void __user *user, unsigned int len)
        get_counters(oldinfo, counters);
        /* Decrease module usage counts and free resource */
        loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()];
-       ARPT_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL);
+       ARPT_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,
+                          NULL);
 
        xt_free_table_info(oldinfo);
-       if (copy_to_user(tmp.counters, counters,
-                        sizeof(struct xt_counters) * tmp.num_counters) != 0)
+       if (copy_to_user(counters_ptr, counters,
+                        sizeof(struct xt_counters) * num_counters) != 0)
                ret = -EFAULT;
        vfree(counters);
        xt_table_unlock(t);
@@ -954,9 +1013,53 @@ static int do_replace(void __user *user, unsigned int len)
        module_put(t->me);
        xt_table_unlock(t);
  free_newinfo_counters_untrans:
-       ARPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL);
- free_newinfo_counters:
        vfree(counters);
+ out:
+       return ret;
+}
+
+static int do_replace(void __user *user, unsigned int len)
+{
+       int ret;
+       struct arpt_replace tmp;
+       struct xt_table_info *newinfo;
+       void *loc_cpu_entry;
+
+       if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
+               return -EFAULT;
+
+       /* overflow check */
+       if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
+               return -ENOMEM;
+
+       newinfo = xt_alloc_table_info(tmp.size);
+       if (!newinfo)
+               return -ENOMEM;
+
+       /* choose the copy that is on our node/cpu */
+       loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
+       if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
+                          tmp.size) != 0) {
+               ret = -EFAULT;
+               goto free_newinfo;
+       }
+
+       ret = translate_table(tmp.name, tmp.valid_hooks,
+                             newinfo, loc_cpu_entry, tmp.size, tmp.num_entries,
+                             tmp.hook_entry, tmp.underflow);
+       if (ret != 0)
+               goto free_newinfo;
+
+       duprintf("arp_tables: Translated table\n");
+
+       ret = __do_replace(tmp.name, tmp.valid_hooks, newinfo,
+                          tmp.num_counters, tmp.counters);
+       if (ret)
+               goto free_newinfo_untrans;
+       return 0;
+
+ free_newinfo_untrans:
+       ARPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL);
  free_newinfo:
        xt_free_table_info(newinfo);
        return ret;
@@ -976,31 +1079,59 @@ static inline int add_counter_to_entry(struct arpt_entry *e,
        return 0;
 }
 
-static int do_add_counters(void __user *user, unsigned int len)
+static int do_add_counters(void __user *user, unsigned int len, int compat)
 {
        unsigned int i;
-       struct xt_counters_info tmp, *paddc;
+       struct xt_counters_info tmp;
+       struct xt_counters *paddc;
+       unsigned int num_counters;
+       char *name;
+       int size;
+       void *ptmp;
        struct arpt_table *t;
        struct xt_table_info *private;
        int ret = 0;
        void *loc_cpu_entry;
+#ifdef CONFIG_COMPAT
+       struct compat_xt_counters_info compat_tmp;
 
-       if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
+       if (compat) {
+               ptmp = &compat_tmp;
+               size = sizeof(struct compat_xt_counters_info);
+       } else
+#endif
+       {
+               ptmp = &tmp;
+               size = sizeof(struct xt_counters_info);
+       }
+
+       if (copy_from_user(ptmp, user, size) != 0)
                return -EFAULT;
 
-       if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct xt_counters))
+#ifdef CONFIG_COMPAT
+       if (compat) {
+               num_counters = compat_tmp.num_counters;
+               name = compat_tmp.name;
+       } else
+#endif
+       {
+               num_counters = tmp.num_counters;
+               name = tmp.name;
+       }
+
+       if (len != size + num_counters * sizeof(struct xt_counters))
                return -EINVAL;
 
-       paddc = vmalloc_node(len, numa_node_id());
+       paddc = vmalloc_node(len - size, numa_node_id());
        if (!paddc)
                return -ENOMEM;
 
-       if (copy_from_user(paddc, user, len) != 0) {
+       if (copy_from_user(paddc, user + size, len - size) != 0) {
                ret = -EFAULT;
                goto free;
        }
 
-       t = xt_find_table_lock(NF_ARP, tmp.name);
+       t = xt_find_table_lock(NF_ARP, name);
        if (!t || IS_ERR(t)) {
                ret = t ? PTR_ERR(t) : -ENOENT;
                goto free;
@@ -1008,7 +1139,7 @@ static int do_add_counters(void __user *user, unsigned int len)
 
        write_lock_bh(&t->lock);
        private = t->private;
-       if (private->number != tmp.num_counters) {
+       if (private->number != num_counters) {
                ret = -EINVAL;
                goto unlock_up_free;
        }
@@ -1019,7 +1150,7 @@ static int do_add_counters(void __user *user, unsigned int len)
        ARPT_ENTRY_ITERATE(loc_cpu_entry,
                           private->size,
                           add_counter_to_entry,
-                          paddc->counters,
+                          paddc,
                           &i);
  unlock_up_free:
        write_unlock_bh(&t->lock);
@@ -1031,6 +1162,496 @@ static int do_add_counters(void __user *user, unsigned int len)
        return ret;
 }
 
+#ifdef CONFIG_COMPAT
+static inline int
+compat_release_entry(struct compat_arpt_entry *e, unsigned int *i)
+{
+       struct arpt_entry_target *t;
+
+       if (i && (*i)-- == 0)
+               return 1;
+
+       t = compat_arpt_get_target(e);
+       module_put(t->u.kernel.target->me);
+       return 0;
+}
+
+static inline int
+check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
+                                 struct xt_table_info *newinfo,
+                                 unsigned int *size,
+                                 unsigned char *base,
+                                 unsigned char *limit,
+                                 unsigned int *hook_entries,
+                                 unsigned int *underflows,
+                                 unsigned int *i,
+                                 const char *name)
+{
+       struct arpt_entry_target *t;
+       struct xt_target *target;
+       unsigned int entry_offset;
+       int ret, off, h;
+
+       duprintf("check_compat_entry_size_and_hooks %p\n", e);
+       if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0
+           || (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) {
+               duprintf("Bad offset %p, limit = %p\n", e, limit);
+               return -EINVAL;
+       }
+
+       if (e->next_offset < sizeof(struct compat_arpt_entry) +
+                            sizeof(struct compat_xt_entry_target)) {
+               duprintf("checking: element %p size %u\n",
+                        e, e->next_offset);
+               return -EINVAL;
+       }
+
+       /* For purposes of check_entry casting the compat entry is fine */
+       ret = check_entry((struct arpt_entry *)e, name);
+       if (ret)
+               return ret;
+
+       off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
+       entry_offset = (void *)e - (void *)base;
+
+       t = compat_arpt_get_target(e);
+       target = try_then_request_module(xt_find_target(NF_ARP,
+                                                       t->u.user.name,
+                                                       t->u.user.revision),
+                                        "arpt_%s", t->u.user.name);
+       if (IS_ERR(target) || !target) {
+               duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
+                        t->u.user.name);
+               ret = target ? PTR_ERR(target) : -ENOENT;
+               goto out;
+       }
+       t->u.kernel.target = target;
+
+       off += xt_compat_target_offset(target);
+       *size += off;
+       ret = xt_compat_add_offset(NF_ARP, entry_offset, off);
+       if (ret)
+               goto release_target;
+
+       /* Check hooks & underflows */
+       for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
+               if ((unsigned char *)e - base == hook_entries[h])
+                       newinfo->hook_entry[h] = hook_entries[h];
+               if ((unsigned char *)e - base == underflows[h])
+                       newinfo->underflow[h] = underflows[h];
+       }
+
+       /* Clear counters and comefrom */
+       memset(&e->counters, 0, sizeof(e->counters));
+       e->comefrom = 0;
+
+       (*i)++;
+       return 0;
+
+release_target:
+       module_put(t->u.kernel.target->me);
+out:
+       return ret;
+}
+
+static int
+compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
+                           unsigned int *size, const char *name,
+                           struct xt_table_info *newinfo, unsigned char *base)
+{
+       struct arpt_entry_target *t;
+       struct xt_target *target;
+       struct arpt_entry *de;
+       unsigned int origsize;
+       int ret, h;
+
+       ret = 0;
+       origsize = *size;
+       de = (struct arpt_entry *)*dstptr;
+       memcpy(de, e, sizeof(struct arpt_entry));
+       memcpy(&de->counters, &e->counters, sizeof(e->counters));
+
+       *dstptr += sizeof(struct arpt_entry);
+       *size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
+
+       de->target_offset = e->target_offset - (origsize - *size);
+       t = compat_arpt_get_target(e);
+       target = t->u.kernel.target;
+       xt_compat_target_from_user(t, dstptr, size);
+
+       de->next_offset = e->next_offset - (origsize - *size);
+       for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
+               if ((unsigned char *)de - base < newinfo->hook_entry[h])
+                       newinfo->hook_entry[h] -= origsize - *size;
+               if ((unsigned char *)de - base < newinfo->underflow[h])
+                       newinfo->underflow[h] -= origsize - *size;
+       }
+       return ret;
+}
+
+static inline int compat_check_entry(struct arpt_entry *e, const char *name,
+                                    unsigned int *i)
+{
+       int ret;
+
+       ret = check_target(e, name);
+       if (ret)
+               return ret;
+
+       (*i)++;
+       return 0;
+}
+
+static int translate_compat_table(const char *name,
+                                 unsigned int valid_hooks,
+                                 struct xt_table_info **pinfo,
+                                 void **pentry0,
+                                 unsigned int total_size,
+                                 unsigned int number,
+                                 unsigned int *hook_entries,
+                                 unsigned int *underflows)
+{
+       unsigned int i, j;
+       struct xt_table_info *newinfo, *info;
+       void *pos, *entry0, *entry1;
+       unsigned int size;
+       int ret;
+
+       info = *pinfo;
+       entry0 = *pentry0;
+       size = total_size;
+       info->number = number;
+
+       /* Init all hooks to impossible value. */
+       for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
+               info->hook_entry[i] = 0xFFFFFFFF;
+               info->underflow[i] = 0xFFFFFFFF;
+       }
+
+       duprintf("translate_compat_table: size %u\n", info->size);
+       j = 0;
+       xt_compat_lock(NF_ARP);
+       /* Walk through entries, checking offsets. */
+       ret = COMPAT_ARPT_ENTRY_ITERATE(entry0, total_size,
+                                       check_compat_entry_size_and_hooks,
+                                       info, &size, entry0,
+                                       entry0 + total_size,
+                                       hook_entries, underflows, &j, name);
+       if (ret != 0)
+               goto out_unlock;
+
+       ret = -EINVAL;
+       if (j != number) {
+               duprintf("translate_compat_table: %u not %u entries\n",
+                        j, number);
+               goto out_unlock;
+       }
+
+       /* Check hooks all assigned */
+       for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
+               /* Only hooks which are valid */
+               if (!(valid_hooks & (1 << i)))
+                       continue;
+               if (info->hook_entry[i] == 0xFFFFFFFF) {
+                       duprintf("Invalid hook entry %u %u\n",
+                                i, hook_entries[i]);
+                       goto out_unlock;
+               }
+               if (info->underflow[i] == 0xFFFFFFFF) {
+                       duprintf("Invalid underflow %u %u\n",
+                                i, underflows[i]);
+                       goto out_unlock;
+               }
+       }
+
+       ret = -ENOMEM;
+       newinfo = xt_alloc_table_info(size);
+       if (!newinfo)
+               goto out_unlock;
+
+       newinfo->number = number;
+       for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
+               newinfo->hook_entry[i] = info->hook_entry[i];
+               newinfo->underflow[i] = info->underflow[i];
+       }
+       entry1 = newinfo->entries[raw_smp_processor_id()];
+       pos = entry1;
+       size = total_size;
+       ret = COMPAT_ARPT_ENTRY_ITERATE(entry0, total_size,
+                                       compat_copy_entry_from_user,
+                                       &pos, &size, name, newinfo, entry1);
+       xt_compat_flush_offsets(NF_ARP);
+       xt_compat_unlock(NF_ARP);
+       if (ret)
+               goto free_newinfo;
+
+       ret = -ELOOP;
+       if (!mark_source_chains(newinfo, valid_hooks, entry1))
+               goto free_newinfo;
+
+       i = 0;
+       ret = ARPT_ENTRY_ITERATE(entry1, newinfo->size, compat_check_entry,
+                                name, &i);
+       if (ret) {
+               j -= i;
+               COMPAT_ARPT_ENTRY_ITERATE_CONTINUE(entry0, newinfo->size, i,
+                                                  compat_release_entry, &j);
+               ARPT_ENTRY_ITERATE(entry1, newinfo->size, cleanup_entry, &i);
+               xt_free_table_info(newinfo);
+               return ret;
+       }
+
+       /* And one copy for every other CPU */
+       for_each_possible_cpu(i)
+               if (newinfo->entries[i] && newinfo->entries[i] != entry1)
+                       memcpy(newinfo->entries[i], entry1, newinfo->size);
+
+       *pinfo = newinfo;
+       *pentry0 = entry1;
+       xt_free_table_info(info);
+       return 0;
+
+free_newinfo:
+       xt_free_table_info(newinfo);
+out:
+       COMPAT_ARPT_ENTRY_ITERATE(entry0, total_size, compat_release_entry, &j);
+       return ret;
+out_unlock:
+       xt_compat_flush_offsets(NF_ARP);
+       xt_compat_unlock(NF_ARP);
+       goto out;
+}
+
+struct compat_arpt_replace {
+       char                            name[ARPT_TABLE_MAXNAMELEN];
+       u32                             valid_hooks;
+       u32                             num_entries;
+       u32                             size;
+       u32                             hook_entry[NF_ARP_NUMHOOKS];
+       u32                             underflow[NF_ARP_NUMHOOKS];
+       u32                             num_counters;
+       compat_uptr_t                   counters;
+       struct compat_arpt_entry        entries[0];
+};
+
+static int compat_do_replace(void __user *user, unsigned int len)
+{
+       int ret;
+       struct compat_arpt_replace tmp;
+       struct xt_table_info *newinfo;
+       void *loc_cpu_entry;
+
+       if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
+               return -EFAULT;
+
+       /* overflow check */
+       if (tmp.size >= INT_MAX / num_possible_cpus())
+               return -ENOMEM;
+       if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
+               return -ENOMEM;
+
+       newinfo = xt_alloc_table_info(tmp.size);
+       if (!newinfo)
+               return -ENOMEM;
+
+       /* choose the copy that is on our node/cpu */
+       loc_cpu_entry = newinfo->entries[raw_smp_processor_id()];
+       if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) {
+               ret = -EFAULT;
+               goto free_newinfo;
+       }
+
+       ret = translate_compat_table(tmp.name, tmp.valid_hooks,
+                                    &newinfo, &loc_cpu_entry, tmp.size,
+                                    tmp.num_entries, tmp.hook_entry,
+                                    tmp.underflow);
+       if (ret != 0)
+               goto free_newinfo;
+
+       duprintf("compat_do_replace: Translated table\n");
+
+       ret = __do_replace(tmp.name, tmp.valid_hooks, newinfo,
+                          tmp.num_counters, compat_ptr(tmp.counters));
+       if (ret)
+               goto free_newinfo_untrans;
+       return 0;
+
+ free_newinfo_untrans:
+       ARPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry, NULL);
+ free_newinfo:
+       xt_free_table_info(newinfo);
+       return ret;
+}
+
+static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user,
+                                 unsigned int len)
+{
+       int ret;
+
+       if (!capable(CAP_NET_ADMIN))
+               return -EPERM;
+
+       switch (cmd) {
+       case ARPT_SO_SET_REPLACE:
+               ret = compat_do_replace(user, len);
+               break;
+
+       case ARPT_SO_SET_ADD_COUNTERS:
+               ret = do_add_counters(user, len, 1);
+               break;
+
+       default:
+               duprintf("do_arpt_set_ctl:  unknown request %i\n", cmd);
+               ret = -EINVAL;
+       }
+
+       return ret;
+}
+
+static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr,
+                                    compat_uint_t *size,
+                                    struct xt_counters *counters,
+                                    unsigned int *i)
+{
+       struct arpt_entry_target *t;
+       struct compat_arpt_entry __user *ce;
+       u_int16_t target_offset, next_offset;
+       compat_uint_t origsize;
+       int ret;
+
+       ret = -EFAULT;
+       origsize = *size;
+       ce = (struct compat_arpt_entry __user *)*dstptr;
+       if (copy_to_user(ce, e, sizeof(struct arpt_entry)))
+               goto out;
+
+       if (copy_to_user(&ce->counters, &counters[*i], sizeof(counters[*i])))
+               goto out;
+
+       *dstptr += sizeof(struct compat_arpt_entry);
+       *size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
+
+       target_offset = e->target_offset - (origsize - *size);
+
+       t = arpt_get_target(e);
+       ret = xt_compat_target_to_user(t, dstptr, size);
+       if (ret)
+               goto out;
+       ret = -EFAULT;
+       next_offset = e->next_offset - (origsize - *size);
+       if (put_user(target_offset, &ce->target_offset))
+               goto out;
+       if (put_user(next_offset, &ce->next_offset))
+               goto out;
+
+       (*i)++;
+       return 0;
+out:
+       return ret;
+}
+
+static int compat_copy_entries_to_user(unsigned int total_size,
+                                      struct arpt_table *table,
+                                      void __user *userptr)
+{
+       struct xt_counters *counters;
+       struct xt_table_info *private = table->private;
+       void __user *pos;
+       unsigned int size;
+       int ret = 0;
+       void *loc_cpu_entry;
+       unsigned int i = 0;
+
+       counters = alloc_counters(table);
+       if (IS_ERR(counters))
+               return PTR_ERR(counters);
+
+       /* choose the copy on our node/cpu */
+       loc_cpu_entry = private->entries[raw_smp_processor_id()];
+       pos = userptr;
+       size = total_size;
+       ret = ARPT_ENTRY_ITERATE(loc_cpu_entry, total_size,
+                                compat_copy_entry_to_user,
+                                &pos, &size, counters, &i);
+       vfree(counters);
+       return ret;
+}
+
+struct compat_arpt_get_entries {
+       char name[ARPT_TABLE_MAXNAMELEN];
+       compat_uint_t size;
+       struct compat_arpt_entry entrytable[0];
+};
+
+static int compat_get_entries(struct compat_arpt_get_entries __user *uptr,
+                             int *len)
+{
+       int ret;
+       struct compat_arpt_get_entries get;
+       struct arpt_table *t;
+
+       if (*len < sizeof(get)) {
+               duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get));
+               return -EINVAL;
+       }
+       if (copy_from_user(&get, uptr, sizeof(get)) != 0)
+               return -EFAULT;
+       if (*len != sizeof(struct compat_arpt_get_entries) + get.size) {
+               duprintf("compat_get_entries: %u != %zu\n",
+                        *len, sizeof(get) + get.size);
+               return -EINVAL;
+       }
+
+       xt_compat_lock(NF_ARP);
+       t = xt_find_table_lock(NF_ARP, get.name);
+       if (t && !IS_ERR(t)) {
+               struct xt_table_info *private = t->private;
+               struct xt_table_info info;
+
+               duprintf("t->private->number = %u\n", private->number);
+               ret = compat_table_info(private, &info);
+               if (!ret && get.size == info.size) {
+                       ret = compat_copy_entries_to_user(private->size,
+                                                         t, uptr->entrytable);
+               } else if (!ret) {
+                       duprintf("compat_get_entries: I've got %u not %u!\n",
+                                private->size, get.size);
+                       ret = -EINVAL;
+               }
+               xt_compat_flush_offsets(NF_ARP);
+               module_put(t->me);
+               xt_table_unlock(t);
+       } else
+               ret = t ? PTR_ERR(t) : -ENOENT;
+
+       xt_compat_unlock(NF_ARP);
+       return ret;
+}
+
+static int do_arpt_get_ctl(struct sock *, int, void __user *, int *);
+
+static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user,
+                                 int *len)
+{
+       int ret;
+
+       if (!capable(CAP_NET_ADMIN))
+               return -EPERM;
+
+       switch (cmd) {
+       case ARPT_SO_GET_INFO:
+               ret = get_info(user, len, 1);
+               break;
+       case ARPT_SO_GET_ENTRIES:
+               ret = compat_get_entries(user, len);
+               break;
+       default:
+               ret = do_arpt_get_ctl(sk, cmd, user, len);
+       }
+       return ret;
+}
+#endif
+
 static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
 {
        int ret;
@@ -1044,7 +1665,7 @@ static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned
                break;
 
        case ARPT_SO_SET_ADD_COUNTERS:
-               ret = do_add_counters(user, len);
+               ret = do_add_counters(user, len, 0);
                break;
 
        default:
@@ -1064,7 +1685,7 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len
 
        switch (cmd) {
        case ARPT_SO_GET_INFO:
-               ret = get_info(user, len);
+               ret = get_info(user, len, 0);
                break;
 
        case ARPT_SO_GET_ENTRIES:
@@ -1156,6 +1777,11 @@ static struct arpt_target arpt_standard_target __read_mostly = {
        .name           = ARPT_STANDARD_TARGET,
        .targetsize     = sizeof(int),
        .family         = NF_ARP,
+#ifdef CONFIG_COMPAT
+       .compatsize     = sizeof(compat_int_t),
+       .compat_from_user = compat_standard_from_user,
+       .compat_to_user = compat_standard_to_user,
+#endif
 };
 
 static struct arpt_target arpt_error_target __read_mostly = {
@@ -1170,9 +1796,15 @@ static struct nf_sockopt_ops arpt_sockopts = {
        .set_optmin     = ARPT_BASE_CTL,
        .set_optmax     = ARPT_SO_SET_MAX+1,
        .set            = do_arpt_set_ctl,
+#ifdef CONFIG_COMPAT
+       .compat_set     = compat_do_arpt_set_ctl,
+#endif
        .get_optmin     = ARPT_BASE_CTL,
        .get_optmax     = ARPT_SO_GET_MAX+1,
        .get            = do_arpt_get_ctl,
+#ifdef CONFIG_COMPAT
+       .compat_get     = compat_do_arpt_get_ctl,
+#endif
        .owner          = THIS_MODULE,
 };