Description of problem:

Samba/CTDB 4.2 as shipped in 7.2 updates repo suffers from Samba bug 11844 in a CTDB cluster.

https://bugzilla.samba.org/show_bug.cgi?id=11844


Version-Release number of selected component (if applicable):

Installed Packages
Name        : samba
Arch        : x86_64
Version     : 4.2.10
Release     : 7.el7_2
Size        : 1.8 M
Repo        : installed
From repo   : updates
Summary     : Server and Client software to interoperate with Windows machines
URL         : http://www.samba.org/
Licence     : GPLv3+ and LGPLv3+
Description : Samba is the standard Windows interoperability suite of programs
            : for Linux and Unix.

Installed Packages
Name        : ctdb
Arch        : x86_64
Version     : 4.2.10
Release     : 7.el7_2
Size        : 1.2 M
Repo        : installed
From repo   : updates
Summary     : A Clustered Database based on Samba's Trivial Database (TDB)
URL         : http://www.samba.org/
Licence     : GPLv3+ and LGPLv3+
Description : CTDB is a cluster implementation of the TDB database used by Samba
            : and other projects to store temporary data. If an application is
            : already using TDB for temporary data it is very easy to convert
            : that application to be cluster aware and use CTDB instead.

How reproducible:


Steps to Reproduce:
1. Set up Samba and CTDB on a clustered/distributed filesystem
2. Throw 200-300 production users on mixed XP/W7 clients at the FS
3. Observe random failures accessing files, eg profile files not loading, XLS files not accessible, stuck locks, corrupted EACLs, and "assert failed" in samba logs as described in Samba bugzilla

Actual results:

Failures to access files as expected, samba log:

[2016/09/20 16:04:15.322530,  0] ../source3/smbd/oplock.c:193(update_num_read_oplocks)
  PANIC: assert failed at ../source3/smbd/oplock.c(193): d->num_share_modes == 1
[2016/09/20 16:04:15.322556,  0] ../source3/lib/util.c:788(smb_panic_s3)
  PANIC (pid 21800): assert failed: d->num_share_modes == 1
[2016/09/20 16:04:15.323100,  0] ../source3/lib/util.c:899(log_stack_trace)
  BACKTRACE: 26 stack frames:
   #0 /lib64/libsmbconf.so.0(log_stack_trace+0x1a) [0x7f63b3ba41da]
   #1 /lib64/libsmbconf.so.0(smb_panic_s3+0x20) [0x7f63b3ba42b0]
   #2 /lib64/libsamba-util.so.0(smb_panic+0x2f) [0x7f63b5a2891f]
   #3 /usr/lib64/samba/libsmbd-base-samba4.so(update_num_read_oplocks+0xf9) [0x7f63b5635929]
   #4 /usr/lib64/samba/libsmbd-base-samba4.so(+0x1119d2) [0x7f63b55e09d2]
   #5 /usr/lib64/samba/libsmbd-base-samba4.so(+0x114459) [0x7f63b55e3459]
   #6 /usr/lib64/samba/libsmbd-base-samba4.so(create_file_default+0x1cf) [0x7f63b55e449f]
   #7 /usr/lib64/samba/libsmbd-base-samba4.so(+0x1ed24e) [0x7f63b56bc24e]
   #8 /usr/lib64/samba/libsmbd-base-samba4.so(smb_vfs_call_create_file+0xd8) [0x7f63b55eace8]
   #9 /usr/lib64/samba/libsmbd-base-samba4.so(reply_ntcreate_and_X+0x4b6) [0x7f63b55a1326]
   #10 /usr/lib64/samba/libsmbd-base-samba4.so(+0x12cdb3) [0x7f63b55fbdb3]
   #11 /usr/lib64/samba/libsmbd-base-samba4.so(+0x12ea60) [0x7f63b55fda60]
   #12 /usr/lib64/samba/libsmbd-base-samba4.so(+0x130131) [0x7f63b55ff131]
   #13 /lib64/libsmbconf.so.0(run_events_poll+0x16c) [0x7f63b3bba07c]
   #14 /lib64/libsmbconf.so.0(+0x372d0) [0x7f63b3bba2d0]
   #15 /lib64/libtevent.so.0(_tevent_loop_once+0x8d) [0x7f63b25d636d]
   #16 /lib64/libtevent.so.0(tevent_common_loop_wait+0x1b) [0x7f63b25d650b]
   #17 /usr/lib64/samba/libsmbd-base-samba4.so(smbd_process+0x6d9) [0x7f63b5600419]
   #18 /usr/sbin/smbd(+0xae44) [0x7f63b608ce44]
   #19 /lib64/libsmbconf.so.0(run_events_poll+0x16c) [0x7f63b3bba07c]
   #20 /lib64/libsmbconf.so.0(+0x372d0) [0x7f63b3bba2d0]
   #21 /lib64/libtevent.so.0(_tevent_loop_once+0x8d) [0x7f63b25d636d]
   #22 /lib64/libtevent.so.0(tevent_common_loop_wait+0x1b) [0x7f63b25d650b]
   #23 /usr/sbin/smbd(main+0x1501) [0x7f63b6089361]
   #24 /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f63b2231b15]
   #25 /usr/sbin/smbd(+0x7765) [0x7f63b6089765]
[2016/09/20 16:04:15.323170,  0] ../source3/lib/dumpcore.c:318(dump_core)
  dumping core in /var/log/samba/cores/smbd

Expected results:

Ability to consistently access files via SAMBA/CTDB cluster

Additional info:

Please backport patch from bugzilla.samba.org to updates