--- Begin Message ---
Package: libnss-ldap
Version: 238-1sarge1
Severity: important
Apologies for the vague subject, but I don't know exactly how to
describe this bug in so few words. I'll explain.
On a Debian 3.1-based mailserver running Cyrus IMAPd 2.2 (cyrus22-*
packages) and Exim4, some strange behaviour started after upgrading to
version 238-1sarge1 of libnss-ldap. Cyrus invokes the sendmail binary to
deliver, for example, error message and vacation autoreplies.
/usr/sbin/sendmail is a symlink to /usr/sbin/exim4. When Exim is invokes
as sendmail, its behaviour is slightly changed. The exim4 binary is
setuid root.
Now, when using the 238-1sarge1 version of libnss-ldap, something has
changed in the suid behaviour, because when Cyrus tries to invoke
sendmail (actually exim), the latter complains that there is
insufficient privileges, causing the Cyrus-generated message to be lost.
I don't know exactly what's going on, but it's an interaction between
Cyrus, Exim and libnss-ldap -- perhaps it has something to do with group
membership and the altered behaviour of libnss-ldap.
Also, if nscd is not running, all programs on this box invoked from a
bash shell will immediately segfault. It's impossible to strace the
processes, because strace will obviously also segfault. Turning on nscd
again stops the segfaulting.
I'm not at all sure what's going on here, so please ask for any details
you may require to debug this. I'm attaching my nsswitch.conf and
libnss-ldap.conf.
Thanks,
--
Fabian Fagerholm <[email protected]>
-- System Information:
Debian Release: 3.1
Architecture: i386 (i686)
Kernel: Linux 2.6.8-4-k7
Locale: LANG=en_US, LC_CTYPE=en_US (charmap=ISO-8859-1)
Versions of packages libnss-ldap depends on:
ii debconf 1.4.30.13 Debian configuration management sy
ii libc6 2.3.2.ds1-22sarge6 GNU C Library: Shared libraries an
ii libkrb53 1.3.6-2sarge5 MIT Kerberos runtime libraries
ii libldap2 2.1.30-8 OpenLDAP libraries
-- debconf information:
* libnss-ldap/dblogin: false
* libnss-ldap/override: true
* shared/ldapns/base-dn: ou=xyz,dc=example,dc=com
* shared/ldapns/ldap-server: 127.0.0.1
* libnss-ldap/confperm: true
* shared/ldapns/ldap_version: 3
libnss-ldap/binddn: cn=proxyuser,dc=example,dc=com
* libnss-ldap/nsswitch:
# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.
passwd: compat ldap
group: compat ldap
shadow: compat ldap
hosts: files dns
networks: files
protocols: db files
services: db files
ethers: db files
rpc: db files
netgroup: nis
###DEBCONF###
# the configuration of this file will be done by debconf as long as the
# first line of the file says '###DEBCONF###'
#
# you should use dpkg-reconfigure libnss-ldap to configure this file.
#
@(#)$Id: ldap.conf,v 2.41 2005/03/23 08:30:16 lukeh Exp $
#
# This is the configuration file for the LDAP nameservice
# switch library and the LDAP PAM module.
#
# PADL Software
# http://www.padl.com
#
# Your LDAP server. Must be resolvable without using LDAP.
# Multiple hosts may be specified, each separated by a
# space. How long nss_ldap takes to failover depends on
# whether your LDAP client library supports configurable
# network or connect timeouts (see bind_timelimit).
host 127.0.0.1
# The distinguished name of the search base.
base ou=xyz,dc=example,dc=com
# Another way to specify your LDAP server is to provide an
# uri with the server name. This allows to use
# Unix Domain Sockets to connect to a local LDAP Server.
#uri ldap://127.0.0.1/
#uri ldaps://127.0.0.1/
#uri ldapi://%2fvar%2frun%2fldapi_sock/
# Note: %2f encodes the '/' used as directory separator
# The LDAP version to use (defaults to 3
# if supported by client library)
ldap_version 3
# The distinguished name to bind to the server with.
# Optional: default is to bind anonymously.
#binddn cn=pamuser,dc=example,dc=com
# The credentials to bind with.
# Optional: default is no credential.
#bindpw xxxxxxxxxxxx
# The distinguished name to bind to the server with
# if the effective user ID is root. Password is
# stored in /etc/ldap.secret (mode 600)
#rootbinddn cn=manager,dc=padl,dc=com
# The port.
# Optional: default is 389.
#port 389
# The search scope.
#scope sub
#scope one
#scope base
# Search timelimit
#timelimit 30
# Bind/connect timelimit
#bind_timelimit 30
# Reconnect policy:
# hard_open: reconnect to DSA with exponential backoff if
# opening connection failed
# hard_init: reconnect to DSA with exponential backoff if
# initializing connection failed
# hard: alias for hard_open
# soft: return immediately on server failure
#bind_policy hard
# Idle timelimit; client will close connections
# (nss_ldap only) if the server has not been contacted
# for the number of seconds specified below.
#idle_timelimit 3600
# Pagesize: when configured with --enable-paged-results allow
# to set the pagesize to a custom value
#pagesize 1000
# Filter to AND with uid=%s
pam_filter objectclass=posixAccount
# The user ID attribute (defaults to uid)
#pam_login_attribute uid
# Search the root DSE for the password policy (works
# with Netscape Directory Server)
#pam_lookup_policy yes
# Check the 'host' attribute for access control
# Default is no; if set to yes, and user has no
# value for the host attribute, and pam_ldap is
# configured for account management (authorization)
# then the user will not be allowed to login.
#pam_check_host_attr yes
# Check the 'authorizedService' attribute for access
# control
# Default is no; if set to yes, and the user has no
# value for the authorizedService attribute, and
# pam_ldap is configured for account management
# (authorization) then the user will not be allowed
# to login.
#pam_check_service_attr yes
# Group to enforce membership of
#pam_groupdn cn=PAM,ou=Groups,dc=padl,dc=com
# Group member attribute
#pam_member_attribute uniquemember
# Specify a minium or maximum UID number allowed
pam_min_uid 1000
#pam_max_uid 0
# Template login attribute, default template user
# (can be overriden by value of former attribute
# in user's entry)
#pam_login_attribute userPrincipalName
#pam_template_login_attribute uid
#pam_template_login nobody
# HEADS UP: the pam_crypt, pam_nds_passwd,
# and pam_ad_passwd options are no
# longer supported.
#
# If you are using XAD, you can set pam_password
# to racf, ad, or exop. Make sure that you have
# SSL enabled.
# Do not hash the password at all; presume
# the directory server will do it, if
# necessary. This is the default.
#pam_password clear
# Hash password locally; required for University of
# Michigan LDAP server, and works with Netscape
# Directory Server if you're using the UNIX-Crypt
# hash mechanism and not using the NT Synchronization
# service.
#pam_password crypt
# Remove old password first, then update in
# cleartext. Necessary for use with Novell
# Directory Services (NDS)
#pam_password nds
# RACF is an alias for the above. For use with
# IBM RACF
#pam_password racf
# Update Active Directory password, by
# creating Unicode password and updating
# unicodePwd attribute.
#pam_password ad
# Use the OpenLDAP password change
# extended operation to update the password.
#pam_password exop
# Redirect users to a URL or somesuch on password
# changes.
#pam_password_prohibit_message Please visit http://internal to change your
password.
# RFC2307bis naming contexts
# Syntax:
# nss_base_XXX base?scope?filter
# where scope is {base,one,sub}
# and filter is a filter to be &'d with the
# default filter.
# You can omit the suffix eg:
# nss_base_passwd ou=People,
# to append the default base DN but this
# may incur a small performance impact.
#nss_base_passwdou=People,dc=padl,dc=com?one
#nss_base_shadowou=People,dc=padl,dc=com?one
#nss_base_group ou=Group,dc=padl,dc=com?one
#nss_base_hosts ou=Hosts,dc=padl,dc=com?one
#nss_base_servicesou=Services,dc=padl,dc=com?one
#nss_base_networksou=Networks,dc=padl,dc=com?one
#nss_base_protocolsou=Protocols,dc=padl,dc=com?one
#nss_base_rpc ou=Rpc,dc=padl,dc=com?one
#nss_base_ethersou=Ethers,dc=padl,dc=com?one
#nss_base_netmasksou=Networks,dc=padl,dc=com?ne
#nss_base_bootparamsou=Ethers,dc=padl,dc=com?one
#nss_base_aliasesou=Aliases,dc=padl,dc=com?one
#nss_base_netgroupou=Netgroup,dc=padl,dc=com?one
# attribute/objectclass mapping
# Syntax:
#nss_map_attributerfc2307attribute mapped_attribute
#nss_map_objectclassrfc2307objectclass mapped_objectclass
# configure --enable-nds is no longer supported.
# NDS mappings
#nss_map_attribute uniqueMember member
# Services for UNIX 3.5 mappings
#nss_map_objectclass posixAccount User
#nss_map_objectclass shadowAccount User
#nss_map_attribute uid msSFU30Name
#nss_map_attribute uniqueMember msSFU30PosixMember
#nss_map_attribute userPassword msSFU30Password
#nss_map_attribute homeDirectory msSFU30HomeDirectory
#nss_map_attribute homeDirectory msSFUHomeDirectory
#nss_map_objectclass posixGroup Group
#pam_login_attribute msSFU30Name
#pam_filter objectclass=User
#pam_password ad
# configure --enable-mssfu-schema is no longer supported.
# Services for UNIX 2.0 mappings
#nss_map_objectclass posixAccount User
#nss_map_objectclass shadowAccount user
#nss_map_attribute uid msSFUName
#nss_map_attribute uniqueMember posixMember
#nss_map_attribute userPassword msSFUPassword
#nss_map_attribute homeDirectory msSFUHomeDirectory
#nss_map_attribute shadowLastChange pwdLastSet
#nss_map_objectclass posixGroup Group
#nss_map_attribute cn msSFUName
#pam_login_attribute msSFUName
#pam_filter objectclass=User
#pam_password ad
# RFC 2307 (AD) mappings
#nss_map_objectclass posixAccount user
#nss_map_objectclass shadowAccount user
#nss_map_attribute uid sAMAccountName
#nss_map_attribute homeDirectory unixHomeDirectory
#nss_map_attribute shadowLastChange pwdLastSet
#nss_map_objectclass posixGroup group
#nss_map_attribute uniqueMember member
#pam_login_attribute sAMAccountName
#pam_filter objectclass=User
#pam_password ad
# configure --enable-authpassword is no longer supported
# AuthPassword mappings
#nss_map_attribute userPassword authPassword
# AIX SecureWay mappings
#nss_map_objectclass posixAccount aixAccount
#nss_base_passwd ou=aixaccount,?one
#nss_map_attribute uid userName
#nss_map_attribute gidNumber gid
#nss_map_attribute uidNumber uid
#nss_map_attribute userPassword passwordChar
#nss_map_objectclass posixGroup aixAccessGroup
#nss_base_group ou=aixgroup,?one
#nss_map_attribute cn groupName
#nss_map_attribute uniqueMember member
#pam_login_attribute userName
#pam_filter objectclass=aixAccount
#pam_password clear
# Netscape SDK LDAPS
#ssl on
# Netscape SDK SSL options
#sslpath /etc/ssl/certs/cert7.db
# OpenLDAP SSL mechanism
# start_tls mechanism uses the normal LDAP port, LDAPS typically 636
#ssl start_tls
#ssl on
# OpenLDAP SSL options
# Require and verify server certificate (yes/no)
# Default is to use libldap's default behavior, which can be configured in
# /etc/openldap/ldap.conf using the TLS_REQCERT setting. The default for
# OpenLDAP 2.0 and earlier is "no", for 2.1 and later is "yes".
#tls_checkpeer yes
# CA certificates for server certificate verification
# At least one of these are required if tls_checkpeer is "yes"
#tls_cacertfile /etc/ssl/ca.cert
#tls_cacertdir /etc/ssl/certs
# Seed the PRNG if /dev/urandom is not provided
#tls_randfile /var/run/egd-pool
# SSL cipher suite
# See man ciphers for syntax
#tls_ciphers TLSv1
# Client certificate and key
# Use these, if your server requires client authentication.
#tls_cert
#tls_key
# Disable SASL security layers. This is needed for AD.
#sasl_secprops maxssf=0
# Override the default Kerberos ticket cache location.
#krb5_ccname FILE:/etc/.ldapcache
--- End Message ---
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