(ITS#4185) duplicate/inconsistent attributeTypes may pollute OID/name space with dangling pointer(s)

[ando@sys-net.it]

Full_Name: Pierangelo Masarati
Version: HEAD/re23
OS: irrelevant
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (81.72.89.40)
Submitted by: ando


When registering an attributeType whose name(s), or some of them, are already
registered, no "roll-back" of the already registered names/OID occur; first of
all these pollute the OID/name space; but most of all, they refer to freed
memory and thus endanger the entire attributeType AVL tree.

This is a minor problem that only occurs when reading inconsistent schema
files.

A fix is in HEAD.  I fear the same may be necessary for objectClasses, still
investigating.