id

[Jukka Hienola]

Hi!

I encountered a strange behaviour with id using nss_ldap/pam_ldap.

I'm using OpenLDAP 2.2.13-6.4E on CentOS 4.4. Final Linux with 
nss_ldap-226-17. Kernel is 2.6.9-42.0.10.ELsmp on Intel Dual Xeon, 64-bit.

I have in POSIX group 666 about 150 users listed with memberUid 
attribute. When I tried to get user data with id, I encountered the 
following behaviour:

address@hidden ~]$ sudo id username
id: ../../../libraries/liblber/io.c:171: ber_free_buf: Assertion 
`((ber)->ber_opts.lbo_valid==0x2)' failed.
uid=1111(username) gid=513(Domain Users) groups=513(Domain Users),666

address@hidden ~]$ sudo id username

address@hidden ~]$ sudo id username
id: ../../../libraries/liblber/io.c:171: ber_free_buf: Assertion 
`((ber)->ber_opts.lbo_valid==0x2)' failed.
uid=1111(username) gid=513(Domain Users) groups=513(Domain
Users),666

address@hidden ~]$ sudo id username
id: ../../../libraries/liblber/io.c:171: ber_free_buf: Assertion 
`((ber)->ber_opts.lbo_valid==0x2)' failed.
uid=1111(username) gid=513(Domain Users) groups=513(Domain Users),666

address@hidden ~]$ sudo id username
*** glibc detected *** double free or corruption (out): 
0x0000000000584360 ***
uid=1111(username) gid=513(Domain Users) groups=513(Domain 
Users),512(Domain Admins),544(Administrators),550(Print 
Operators),551(Backup Operators),552(Replicators),666(Some 
Groups),600(Some Other Gr

etc. etc.

Only way I got id to behave as eexpected was to remove some (arbitrary) 
accounts from group 666 and thus reduce the number of memberUid values 
(e.g. usernames in my case). After that id behaved well.

So, I wonder if this could be result of somekind of buffer overflow bug 
in id or in C-library etc.

This behaviour occurs only on my master LDAP-server (information of the 
system in the beginning of this email). On my LDAP-slaves (currently 
RHEL3 and FC5) id works well.

Jukka
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