(ITS#8759) mixed overlay nops & memberof cause segfault

[zhixu.liu@gmail.com]

Full_Name: Z. Liu
Version: 2.4.44
OS: Gentoo
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (221.218.169.84)


if we enable overlay nops & memberof together, then doing a member MODDN
operation, slapd will segfault and exit immediately.

Example operation:

dn: uid=test,ou=People,dc=example,dc=dc=com
changetype: moddn
newrdn: uid=chenln
deleteoldrdn: 1
newsuperior: ou=Leave,dc=example,dc=com

The reason is: in servers/slapd/overlays/memberof.c, function
memberof_value_modify define mod/values/nvalues in the stack, which will be
passed to other overlays, nops will try to free them if no attribute is changed.