Merge tag 'v3.10.103' into update

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv4 / netfilter / arp_tables.c

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 95a5f261fe8a3ab594d990f6df653781f8df5c95..bb1670b371d2050524269539cd9b506899ff0562 100644 (file)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -469,6 +469,23 @@ static int mark_source_chains(const struct xt_table_info *newinfo,
        return 1;
 }
 
+static inline int check_entry(const struct arpt_entry *e)
+{
+       const struct xt_entry_target *t;
+
+       if (!arp_checkentry(&e->arp))
+               return -EINVAL;
+
+       if (e->target_offset + sizeof(struct xt_entry_target) > e->next_offset)
+               return -EINVAL;
+
+       t = arpt_get_target_c(e);
+       if (e->target_offset + t->u.target_size > e->next_offset)
+               return -EINVAL;
+
+       return 0;
+}
+
 static inline int check_target(struct arpt_entry *e, const char *name)
 {
        struct xt_entry_target *t = arpt_get_target(e);
@@ -558,11 +575,8 @@ static inline int check_entry_size_and_hooks(struct arpt_entry *e,
                return -EINVAL;
        }
 
-       if (!arp_checkentry(&e->arp))
-               return -EINVAL;
+       err = check_entry(e);
 
-       err = xt_check_entry_offsets(e, e->elems, e->target_offset,
-                                    e->next_offset);
        if (err)
                return err;
 
@@ -1195,11 +1209,9 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
                return -EINVAL;
        }
 
-       if (!arp_checkentry(&e->arp))
-               return -EINVAL;
+       /* For purposes of check_entry casting the compat entry is fine */
+       ret = check_entry((struct arpt_entry *)e);
 
-       ret = xt_compat_check_entry_offsets(e, e->elems, e->target_offset,
-                                           e->next_offset);
        if (ret)
                return ret;