[Samba] cores from CentOS 7.5.1804 and 4.7.1-6.el7

[Alan Blumer]

Hello,

I'm receiving repeated cores with the captioned environment. Here's a
snippet from log.smbd:
========================
[2018/07/08 03:01:55.936275,  0] ../lib/util/fault.c:79(fault_report)
  INTERNAL ERROR: Signal 11 in pid 91640 (4.7.1)
  Please read the Trouble-Shooting section of the Samba HOWTO
[2018/07/08 03:01:55.936307,  0] ../lib/util/fault.c:81(fault_report)
  ===============================================================
[2018/07/08 03:01:55.936326,  0] ../source3/lib/util.c:804(smb_panic_s3)
  PANIC (pid 91640): internal error
[2018/07/08 03:01:55.937011,  0] ../source3/lib/util.c:915(log_stack_trace)
  BACKTRACE: 37 stack frames:
   #0 /lib64/libsmbconf.so.0(log_stack_trace+0x1a) [0x7fba3c90da3a]
   #1 /lib64/libsmbconf.so.0(smb_panic_s3+0x20) [0x7fba3c90db10]
   #2 /lib64/libsamba-util.so.0(smb_panic+0x2f) [0x7fba3ea08eaf]
   #3 /lib64/libsamba-util.so.0(+0x250c6) [0x7fba3ea090c6]
   #4 /lib64/libpthread.so.0(+0xf6d0) [0x7fba3ee706d0]
   #5 /usr/lib64/samba/libgse-samba4.so(+0x9530) [0x7fba36f76530]
   #6 /usr/lib64/samba/libgse-samba4.so(gse_krb5_get_server_keytab+0x87)
[0x7fba36f76f07]
   #7 /usr/lib64/samba/libgse-samba4.so(+0xc1d8) [0x7fba36f791d8]
   #8 /usr/lib64/samba/libgensec-samba4.so(+0x19eba) [0x7fba36d5beba]
   #9 /usr/lib64/samba/libgensec-samba4.so(gensec_start_mech_by_ops+0xc)
[0x7fba36d5ccbc]
   #10 /usr/lib64/samba/libgensec-samba4.so(+0xac5c) [0x7fba36d4cc5c]
   #11 /usr/lib64/samba/libgensec-samba4.so(+0xc214) [0x7fba36d4e214]
   #12 /usr/lib64/samba/libgensec-samba4.so(gensec_update_ev+0x7f)
[0x7fba36d5b6cf]
   #13 /usr/lib64/samba/libgensec-samba4.so(gensec_update+0x17)
[0x7fba36d5b7c7]
   #14 /usr/lib64/samba/libsmbd-base-samba4.so(negprot_spnego+0xa9)
[0x7fba3e5a8f09]
   #15
/usr/lib64/samba/libsmbd-base-samba4.so(smbd_smb2_request_process_negprot+0x2ca)
[0x7fba3e62330a]
   #16
/usr/lib64/samba/libsmbd-base-samba4.so(smbd_smb2_request_dispatch+0x1bcc)
[0x7fba3e62009c]
   #17
/usr/lib64/samba/libsmbd-base-samba4.so(smbd_smb2_process_negprot+0x370)
[0x7fba3e622ac0]
   #18 /usr/lib64/samba/libsmbd-base-samba4.so(reply_negprot+0x72e)
[0x7fba3e5a9e7e]
   #19 /usr/lib64/samba/libsmbd-base-samba4.so(+0x19ec90) [0x7fba3e60ac90]
   #20 /usr/lib64/samba/libsmbd-base-samba4.so(+0x1a0a30) [0x7fba3e60ca30]
   #21 /usr/lib64/samba/libsmbd-base-samba4.so(+0x1a2111) [0x7fba3e60e111]
   #22 /lib64/libtevent.so.0(+0xaf6b) [0x7fba3b318f6b]
   #23 /lib64/libtevent.so.0(+0x9337) [0x7fba3b317337]
   #24 /lib64/libtevent.so.0(_tevent_loop_once+0x9d) [0x7fba3b31310d]
   #25 /lib64/libtevent.so.0(tevent_common_loop_wait+0x1b) [0x7fba3b31333b]
   #26 /lib64/libtevent.so.0(+0x92d7) [0x7fba3b3172d7]
   #27 /usr/lib64/samba/libsmbd-base-samba4.so(smbd_process+0x6e4)
[0x7fba3e60f444]
   #28 /usr/sbin/smbd(+0xd1d4) [0x55bd819e51d4]
   #29 /lib64/libtevent.so.0(+0xaf6b) [0x7fba3b318f6b]
   #30 /lib64/libtevent.so.0(+0x9337) [0x7fba3b317337]
   #31 /lib64/libtevent.so.0(_tevent_loop_once+0x9d) [0x7fba3b31310d]
   #32 /lib64/libtevent.so.0(tevent_common_loop_wait+0x1b) [0x7fba3b31333b]
   #33 /lib64/libtevent.so.0(+0x92d7) [0x7fba3b3172d7]
   #34 /usr/sbin/smbd(main+0x1afe) [0x55bd819e025e]
   #35 /lib64/libc.so.6(__libc_start_main+0xf5) [0x7fba3af63445]
   #36 /usr/sbin/smbd(+0x8571) [0x55bd819e0571]
[2018/07/08 03:01:55.937278,  0] ../source3/lib/dumpcore.c:318(dump_core)
  coredump is handled by helper binary specified at
/proc/sys/kernel/core_pattern[2018/07/08 03:01:59.445063,  1]
../source3/smbd/smbd_cleanupd.c:99(smbd_cle
anupd_unlock)
============================
Here's our smb.conf:

[global]
mangled names = no
load printers = no
socket options = TCP_NODELAY IPTOS_LOWDELAY
deadtime = 15
winbind use default domain = no
realm = OURDOMAIN.ORG
passdb backend = tdbsam
template shell = /bin/false
cups options = raw
netbios name = SERVERNAME
server string = Samba Server Version %v
hide files = /desktop.ini/ntuser.ini/NTUSER.*/lost+found/
workgroup = OURDOMAIN
os level = 20
security = ADS
preferred master = no
machine password timeout = 0
log level = 1
        max log size = 10000
ea support = yes
map acl inherit = yes
store dos attributes = yes

[homes]
comment = Home Directories
browseable = no
writeable = yes
vfs objects = acl_xattr fruit streams_xattr
[agency]
comment = Shared Data
path = /data/foldername
browseable = yes
valid users = +domain^users
guest ok = no
writeable = yes
printable = no
write list = +domain^users
oplocks = False
level2 oplocks = False
vfs objects = acl_xattr fruit streams_xattr

[share]
oplocks = False
browseable = yes
read list = +AUDIT_ONLY
writeable = yes
printable = no
path = /data/agency/share
write list = +domain^users
comment = Shared Data
valid users = +domain^users,+AUDIT_ONLY
level2 oplocks = False
vfs objects = acl_xattr fruit streams_xattr
=====================================
testparm says:

Load smb config files from /etc/samba/smb.conf
rlimit_max: increasing rlimit_max (1024) to minimum Windows limit (16384)
Processing section "[homes]"
Processing section "[agency]"
Processing section "[share]"
Loaded services file OK.
idmap range not specified for domain '*'
ERROR: Invalid idmap range for domain *!

Server role: ROLE_DOMAIN_MEMBER

======================================

The smb service starts up with no issue, but each time a client attempts to
map a drive to a share, core is dumped.

What else should I provide?
-- 
Alan Blumer
IT Infrastructure Manager
IT Department
Mosaic