(ITS#5511) SIGABRT in slapo-unique when setting uidNumber to 0

[dwhite@olp.net]

Full_Name: Dan White
Version: 2.4.9
OS: Debian Linux
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (2610:b8:1:0:21a:70ff:fe8f:e0b3)


I'm experiencing SIGABRT crashes when the slapo-unique overlay is enabled, and I
attempt to set one of the unique attributes to '0'.

A configuration snippet:

...
modulepath      /usr/lib/ldap
moduleload      back_bdb
moduleload      smbk5pwd
moduleload      unique
...
overlay unique
#unique_base ou=People,dc=olp,dc=net
unique_attributes uidNumber btcAltUID

I'm triggering the crash while modifying the uidNumber attribute with the
ldapmodify command:

hiro:/var/lib/ldap# ldapsearch -LLL uid=dwhite@olp.net uidNumber
dn: uid=dwhite@olp.net,ou=people,dc=olp,dc=net
uidNumber: 497913425

hiro:/var/lib/ldap# ldapmodify 
dn: uid=dwhite@olp.net,ou=people,dc=olp,dc=net
changeType: modify
replace: uidNumber
uidNumber: 0

modifying entry "uid=dwhite@olp.net,ou=people,dc=olp,dc=net"
ldap_result: Can't contact LDAP server (-1)

If I comment out all the unique overlay related configuration items and restart
slapd, and rerun my ldapmodify command, the process completes normally.

Details from the coredump:

...
Core was generated by `/usr/sbin/slapd -h ldap:/// ldaps:/// ldapi:/// -g root
-u root -f /etc/ldap/sl'.
Program terminated with signal 6, Aborted.
#0  0xb7eee410 in ?? ()
(gdb) thread apply all bt

Thread 3 (process 9354):
#0  0xb7eee410 in ?? ()
#1  0xbfdb51a8 in ?? ()
#2  0x0000248b in ?? ()
#3  0x00000000 in ?? ()

Thread 2 (process 9355):
#0  0xb7eee410 in ?? ()
#1  0xb717a458 in ?? ()
#2  0x00000400 in ?? ()
#3  0x081c4148 in ?? ()
#4  0xb7bf2b0e in epoll_wait () from /lib/tls/i686/cmov/libc.so.6
#5  0x08075ca9 in slapd_daemon_task (ptr=0x0) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/daemon.c:2281
#6  0xb7c5d240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#7  0xb7bf249e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (process 9359):
#0  0xb7eee410 in ?? ()
#1  0xb6d77a38 in ?? ()
#2  0x00000006 in ?? ()
#3  0x0000248f in ?? ()
#4  0xb7b4f811 in raise () from /lib/tls/i686/cmov/libc.so.6
#5  0xb7b50fb9 in abort () from /lib/tls/i686/cmov/libc.so.6
#6  0xb7b48fbf in __assert_fail () from /lib/tls/i686/cmov/libc.so.6
#7  0xb7579032 in build_filter (domain=0x822f130, uri=0x822b748, ad=0x81e20b0,
b=0x82bd980, kp=0xb6878266 "(uidNumber=0", ks=13, ctx=0x82bdab8)
    at /usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/overlays/unique.c:931
#8  0xb7579d89 in unique_modify (op=0x82bd6f8, rs=0xb6d791c8) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/overlays/unique.c:1185
#9  0x080f1c69 in overlay_op_walk (op=0x82bd6f8, rs=0xb6d791c8, which=op_modify,
oi=0x822cbc8, on=0x822f148)
    at /usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/backover.c:636
#10 0x080f1ea0 in over_op_func (op=0x82bd6f8, rs=0xb6d791c8, which=op_modify) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/backover.c:698
#11 0x080f1f68 in over_op_modify (op=0x82bd6f8, rs=0xb6d791c8) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/backover.c:732
#12 0x08096290 in fe_op_modify (op=0x82bd6f8, rs=0xb6d791c8) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/modify.c:300
#13 0x08095cd4 in do_modify (op=0x82bd6f8, rs=0xb6d791c8) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/modify.c:175
#14 0x080795c2 in connection_operation (ctx=0xb6d792ac, arg_v=0x82bd6f8) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/connection.c:1084
#15 0x08079aaf in connection_read_thread (ctx=0xb6d792ac, argv=0x12) at
/usr/src/build/slapd.noopt/openldap-2.4.9/servers/slapd/connection.c:1211
#16 0xb7ea812e in ldap_int_thread_pool_wrapper (xpool=0x81e38d0) at
/usr/src/build/slapd.noopt/openldap-2.4.9/libraries/libldap_r/tpool.c:663
#17 0xb7c5d240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#18 0xb7bf249e in clone () from /lib/tls/i686/cmov/libc.so.6
(gdb) quit