Description of problem:

after upgrading to fedora 31 (no problem before), I face very frequent sssd_be
crashes.
Issue seems related to sssd_ldap though can't be sure.

System is up-to-date with latest components

Version-Release number of selected component (if applicable):
sssd-common-pac-2.2.2-3.fc31.x86_64
sssd-nfs-idmap-2.2.2-3.fc31.x86_64
sssd-krb5-common-2.2.2-3.fc31.x86_64
sssd-krb5-2.2.2-3.fc31.x86_64
sssd-proxy-2.2.2-3.fc31.x86_64
sssd-2.2.2-3.fc31.x86_64
sssd-common-2.2.2-3.fc31.x86_64
sssd-ipa-2.2.2-3.fc31.x86_64
sssd-client-2.2.2-3.fc31.x86_64
sssd-tools-2.2.2-3.fc31.x86_64
python3-sssdconfig-2.2.2-3.fc31.noarch
sssd-client-2.2.2-3.fc31.i686
sssd-ldap-2.2.2-3.fc31.x86_64
sssd-ad-2.2.2-3.fc31.x86_64
sssd-kcm-2.2.2-3.fc31.x86_64


How reproducible:

Happens when using sudo commands, getting error message:

    sudo: PAM account management error: Protocol not supported

Executing sudo multiple times will show same error then works.

Steps to Reproduce:
1.
2.
3.

Actual results:
sudo often fails with message "sudo: PAM account management error: Protocol not
supported"

Expected results:
sudo should work

Additional info:

/var/log/message extract:

Jan 17 09:36:57 maelle systemd-coredump[37859]: Process 37803 (sssd_be) of user
0 dumped core.#012#012Stack trace of thread 37803:#012#0  0x00007f957a350d76
sysdb_user_base_dn (libsss_util.so)#012#1  0x0000558301f47d4b be_refresh_step
(sssd_be)#012#2  0x0000558301f480b2 be_refresh_send (sssd_be)#012#3
0x0000558301f47531 be_ptask_execute (sssd_be)#012#4  0x00007f957a266f3d
tevent_common_invoke_timer_handler (libtevent.so.0)#012#5  0x00007f957a2670e0
tevent_common_loop_timer_delay (libtevent.so.0)#012#6  0x00007f957a2684a9
epoll_event_loop_once (libtevent.so.0)#012#7  0x00007f957a26653b
std_event_loop_once (libtevent.so.0)#012#8  0x00007f957a2615d8
_tevent_loop_once (libtevent.so.0)#012#9  0x00007f957a26187b
tevent_common_loop_wait (libtevent.so.0)#012#10 0x00007f957a2664cb
std_event_loop_wait (libtevent.so.0)#012#11 0x00007f957a380e17 server_loop
(libsss_util.so)#012#12 0x0000558301f3ec42 main (sssd_be)#012#13
0x00007f957a0a41a3 __libc_start_main (libc.so.6)#012#14 0x0000558301f3edfe
_start (sssd_be)
Jan 17 09:36:57 maelle systemd[1]: systemd-coredump@70-37858-0.service:
Succeeded.
Jan 17 09:36:57 maelle abrt-dump-journal-core[993]: Failed to obtain all
required information from journald
Jan 17 09:36:57 maelle abrt-server[37872]: Deleting problem directory
ccpp-2020-01-17-09:36:57.463705-37803 (dup of
ccpp-2020-01-14-09:52:17.183530-1002)
Jan 17 09:36:58 maelle abrt-notification[37906]: Process 1002 (sssd_be) crashed
in sysdb_user_base_dn()



sssd config:

[sssd]
domains = XXX.XXX, files
services = nss, pam, autofs
config_file_version = 2

[domain/files]
#A new files provider was added. This provider mirrors the contents of
/etc/passwd and /etc/group into the SSSD database
id_provider = files

[domain/XXX.XX]
#debug_level = 9 #/var/log/sssd/
id_provider = ldap
auth_provider = ldap
cache_credentials = true
entry_cache_timeout = 5400
#entry_cache_netgroup_timeout =
#You can consider setting this value to 3/4 * entry_cache_timeout.
refresh_expired_interval = 4000
ldap_uri = ldaps://ldap.XXX.XXX.XXX
ldap_search_base = ou=XXX,dc=XXX,dc=XXX
#ldap_id_use_start_tls = true
ldap_tls_cacert = /etc/ssl/certs/chain-TCS.pem
ldap_schema = rfc2307bis
#Number of days entries are left in cache after last successful login before
being removed during a cleanup of the cache. 0 means keep forever. The value of
this parameter must be greater than or equal to offline_credentials_expiration
#account_cache_expiration = 45

# By default SSSD will use the value retrieved from LDAP
homedir_substring = /home
override_homedir = %H/%u
override_shell = /usr/bin/bash

autofs_provider = ldap
entry_cache_autofs_timeout = 86400
ldap_autofs_search_base=ou=autofs,ou=XXX,dc=XXX,dc=XXX
#ldap_autofs_map_master_name=

[pam]
# If the authentication provider is offline, how long should we allow cached
logins (in days since the last successful online login). 0 means no limit.
offline_credentials_expiration = 0

[nss]
filter_users = root
filter_groups = root

[autofs]