netfilter: ipset: fix checking the type revision at create command
Jozsef Kadlecsik [Sun, 20 Mar 2011 14:35:01 +0000 (15:35 +0100)]
The revision of the set type was not checked at the create command: if the
userspace sent a valid set type but with not supported revision number,
it'd create a loop.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>

net/netfilter/ipset/ip_set_core.c

index 618a615..d6b4823 100644 (file)
@@ -94,16 +94,28 @@ static int
 find_set_type_get(const char *name, u8 family, u8 revision,
                  struct ip_set_type **found)
 {
+       struct ip_set_type *type;
+       int err;
+
        rcu_read_lock();
        *found = find_set_type(name, family, revision);
        if (*found) {
-               int err = !try_module_get((*found)->me);
-               rcu_read_unlock();
-               return err ? -EFAULT : 0;
+               err = !try_module_get((*found)->me) ? -EFAULT : 0;
+               goto unlock;
        }
+       /* Make sure the type is loaded but we don't support the revision */
+       list_for_each_entry_rcu(type, &ip_set_type_list, list)
+               if (STREQ(type->name, name)) {
+                       err = -IPSET_ERR_FIND_TYPE;
+                       goto unlock;
+               }
        rcu_read_unlock();
 
        return try_to_load_type(name);
+
+unlock:
+       rcu_read_unlock();
+       return err;
 }
 
 /* Find a given set type by name and family.
@@ -116,7 +128,7 @@ find_set_type_minmax(const char *name, u8 family, u8 *min, u8 *max)
        struct ip_set_type *type;
        bool found = false;
 
-       *min = *max = 0;
+       *min = 255; *max = 0;
        rcu_read_lock();
        list_for_each_entry_rcu(type, &ip_set_type_list, list)
                if (STREQ(type->name, name) &&
@@ -124,7 +136,7 @@ find_set_type_minmax(const char *name, u8 family, u8 *min, u8 *max)
                        found = true;
                        if (type->revision < *min)
                                *min = type->revision;
-                       else if (type->revision > *max)
+                       if (type->revision > *max)
                                *max = type->revision;
                }
        rcu_read_unlock();