samba - Apr 2016 - Permission denied in reply to ping_message

Hi all,

I use this command on my servers to test locally that Samba is alive and
well:

smbcontrol smbd ping

However, it suddenly stop working on one of the several identical servers,
and I cannot figure out why. ping command says "no replies received",
while
log.smbd says that it received a ping message, but cannot reply because
permission is denied. Which permission?

$ sudo /usr/bin/smbcontrol -d 3 smbd ping
<...>
rlimit_max: increasing rlimit_max (1024) to minimum Windows limit (16384)
Registered MSG_REQ_POOL_USAGE
Registered MSG_REQ_DMALLOC_MARK and LOG_CHANGED
fcntl_lock: fcntl lock gave errno 11 (Resource temporarily unavailable)
fcntl_lock: lock failed at offset 0 count 1 op 6 type 0 (Resource
temporarily unavailable)
No replies received

log.smbd:
<...>
[2016/03/31 10:00:27.153110,  1] ../source3/lib/messages.c:81(ping_message)
  INFO: Received PING message from PID 30727 []
[2016/03/31 10:00:27.153252,  2]
../source3/lib/messages_local.c:378(message_notify)
  message to process 30727 failed - Permission denied

System is Ubuntu 14.04 x64, Samba 4.1.22.
This is all done by root, apparmor is enabled but doesn't indicate any
denied operations.
-- 
-Alex

If anyone hits this error, it is actually caused by apparmor not allowing
dbus messages being sent.
Including abstractions/dbus in the apparmor profile seems to fix it.

On Fri, Apr 1, 2016 at 9:46 AM, Alex Korobkin <korobkin+smb at gmail.com>
wrote:
> Hi all,
>
> I use this command on my servers to test locally that Samba is alive and
> well:
>
> smbcontrol smbd ping
>
> However, it suddenly stop working on one of the several identical servers,
> and I cannot figure out why. ping command says "no replies
received", while
> log.smbd says that it received a ping message, but cannot reply because
> permission is denied. Which permission?
>
> $ sudo /usr/bin/smbcontrol -d 3 smbd ping
> <...>
> rlimit_max: increasing rlimit_max (1024) to minimum Windows limit (16384)
> Registered MSG_REQ_POOL_USAGE
> Registered MSG_REQ_DMALLOC_MARK and LOG_CHANGED
> fcntl_lock: fcntl lock gave errno 11 (Resource temporarily unavailable)
> fcntl_lock: lock failed at offset 0 count 1 op 6 type 0 (Resource
> temporarily unavailable)
> No replies received
>
> log.smbd:
> <...>
> [2016/03/31 10:00:27.153110,  1] ../source3/lib/messages.c:81(ping_message)
>   INFO: Received PING message from PID 30727 []
> [2016/03/31 10:00:27.153252,  2]
> ../source3/lib/messages_local.c:378(message_notify)
>   message to process 30727 failed - Permission denied
>
> System is Ubuntu 14.04 x64, Samba 4.1.22.
> This is all done by root, apparmor is enabled but doesn't indicate any
> denied operations.
> --
> -Alex
>
>
>

-- 
-Alex