2.4.23 / Debian 6.0 i386: segfault at 811db38 ip 080c1e80 sp b2cf4b80 error 7 in slapd

[David Touzeau <david@touzeau.eu>]

Dear

We have an problem using 
$OpenLDAP: slapd 2.4.23 (Nov 22 2010 23:39:34)
$#012#011@biber:/build/buildd-openldap_2.4.23-7-i386-mi96UQ/openldap-2.4.23/debian/build/servers/slapd

The same issue has been be replicated on 2.4.24

When we analyze the debug logs, the crash is performed each time we see
this line : 

is_entry_objectclass("", "2.16.840.1.113730.3.2.6") no objectClass
attribute

How can we prevent this crash or fix it ?

here it is a piece of logs that detect the crash.

Feb 22 14:50:21 pm02 slapd[12126]: >>> dnPrettyNormal:
<cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com>
Feb 22 14:50:21 pm02 slapd[12126]: <<< dnPrettyNormal:
<cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com>,
<cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com>
Feb 22 14:50:21 pm02 slapd[12126]:
bdb_dn2entry("cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com")
Feb 22 14:50:21 pm02 slapd[12126]: =>
hdb_dn2id("cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com")
Feb 22 14:50:21 pm02 slapd[12126]: <= hdb_dn2id: get failed:
DB_NOTFOUND: No matching key/data pair found (-30988)
Feb 22 14:50:21 pm02 slapd[12126]: oc_check_required entry
(cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com), objectClass
"ArticaHostName"
Feb 22 14:50:21 pm02 slapd[12126]: oc_check_allowed type "objectClass"
Feb 22 14:50:21 pm02 slapd[12126]: oc_check_allowed type "cn"
Feb 22 14:50:21 pm02 slapd[12126]: oc_check_allowed type
"structuralObjectClass"
Feb 22 14:50:21 pm02 slapd[12126]:
bdb_dn2entry("cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com")
Feb 22 14:50:21 pm02 slapd[12126]: =>
hdb_dn2id("cn=webmail.e.florasul.pt,cn=artica,dc=my-domain,dc=com")
Feb 22 14:50:21 pm02 slapd[12126]: <= hdb_dn2id: get failed:
DB_NOTFOUND: No matching key/data pair found (-30988)
Feb 22 14:50:21 pm02 slapd[12126]: is_entry_objectclass("",
"2.16.840.1.113730.3.2.6") no objectClass attribute
Feb 22 14:50:21 pm02 kernel: [13697.801217] slapd[13777]: segfault at
811db38 ip 080c1e80 sp b2cf4b80 error 7 in slapd[8048000+11b000]

best regards