RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1327845 - Enabling spoolssd avoids pcap_cache_reload() during "systemctl reload smb.service"
Summary: Enabling spoolssd avoids pcap_cache_reload() during "systemctl reload smb.ser...
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: samba
Version: 7.2
Hardware: All
OS: Linux
unspecified
medium
Target Milestone: rc
: ---
Assignee: Andreas Schneider
QA Contact: Robin Hack
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2016-04-16 19:13 UTC by Robert Scheck
Modified: 2020-09-10 09:35 UTC (History)
5 users (show)

Fixed In Version: samba-4.4.4-1.el7
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2016-11-04 07:00:33 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2016:2468 0 normal SHIPPED_LIVE samba bug fix and enhancement update 2016-11-03 14:06:51 UTC

Description Robert Scheck 2016-04-16 19:13:17 UTC 
Description of problem:
According to source3/printing/queue_process.c, sending SIGHUP triggers the
bq_sig_hup_handler() which triggers pcap_cache_reload(). This however does
not work at all once Samba is configured with spoolssd as documented in:

  https://wiki.samba.org/index.php/Setup_a_Samba_print_server

Example: Put "rpc_daemon:spoolssd = fork" and "rpc_server:spoolss = external"
into /etc/samba/smb.conf file, perform "systemctl restart smb.service". Then:

$ lpadmin -p test -v socket://test -D test -E
$ systemctl reload smb.service
$ while [ true ]; do
>   date
>   rpcclient localhost -U printadmin%printadmin -c 'enumprinters' | grep test
>   sleep 1
> done
Sa 16. Apr 02:57:00 CEST 2016
Sa 16. Apr 02:57:01 CEST 2016
Sa 16. Apr 02:57:02 CEST 2016
Sa 16. Apr 02:57:03 CEST 2016
Sa 16. Apr 02:57:04 CEST 2016
Sa 16. Apr 02:57:05 CEST 2016
Sa 16. Apr 02:57:06 CEST 2016
Sa 16. Apr 02:57:07 CEST 2016
Sa 16. Apr 02:57:08 CEST 2016
Sa 16. Apr 02:57:09 CEST 2016
Sa 16. Apr 02:57:10 CEST 2016
Sa 16. Apr 02:57:12 CEST 2016
Sa 16. Apr 02:57:13 CEST 2016
Sa 16. Apr 02:57:14 CEST 2016
Sa 16. Apr 02:57:15 CEST 2016
Sa 16. Apr 02:57:16 CEST 2016
Sa 16. Apr 02:57:17 CEST 2016
Sa 16. Apr 02:57:18 CEST 2016
Sa 16. Apr 02:57:19 CEST 2016
Sa 16. Apr 02:57:20 CEST 2016
Sa 16. Apr 02:57:21 CEST 2016
Sa 16. Apr 02:57:22 CEST 2016
Sa 16. Apr 02:57:23 CEST 2016
Sa 16. Apr 02:57:24 CEST 2016
Sa 16. Apr 02:57:25 CEST 2016
Sa 16. Apr 02:57:26 CEST 2016
Sa 16. Apr 02:57:27 CEST 2016
Sa 16. Apr 02:57:28 CEST 2016
Sa 16. Apr 02:57:29 CEST 2016
Sa 16. Apr 02:57:30 CEST 2016
Sa 16. Apr 02:57:31 CEST 2016
Sa 16. Apr 02:57:32 CEST 2016
Sa 16. Apr 02:57:34 CEST 2016
Sa 16. Apr 02:57:35 CEST 2016
Sa 16. Apr 02:57:36 CEST 2016
Sa 16. Apr 02:57:37 CEST 2016
Sa 16. Apr 02:57:38 CEST 2016
Sa 16. Apr 02:57:39 CEST 2016
Sa 16. Apr 02:57:40 CEST 2016
Sa 16. Apr 02:57:41 CEST 2016
Sa 16. Apr 02:57:42 CEST 2016
Sa 16. Apr 02:57:43 CEST 2016
Sa 16. Apr 02:57:44 CEST 2016
Sa 16. Apr 02:57:45 CEST 2016
Sa 16. Apr 02:57:46 CEST 2016
Sa 16. Apr 02:57:47 CEST 2016
Sa 16. Apr 02:57:48 CEST 2016
Sa 16. Apr 02:57:49 CEST 2016
Sa 16. Apr 02:57:50 CEST 2016
Sa 16. Apr 02:57:51 CEST 2016
Sa 16. Apr 02:57:52 CEST 2016
Sa 16. Apr 02:57:53 CEST 2016
Sa 16. Apr 02:57:54 CEST 2016
Sa 16. Apr 02:57:56 CEST 2016
Sa 16. Apr 02:57:57 CEST 2016
Sa 16. Apr 02:57:58 CEST 2016
Sa 16. Apr 02:57:59 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
Sa 16. Apr 02:58:00 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
Sa 16. Apr 02:58:01 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
Sa 16. Apr 02:58:02 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
Sa 16. Apr 02:58:03 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
Sa 16. Apr 02:58:04 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
^C
$ 

The cause for this is "ExecReload=/usr/bin/kill -HUP $MAINPID" in the
systemd unit file /usr/lib/systemd/system/smb.service. Thus only the main
PID of Samba is triggered for a reload, not all child processes.

Using however "ExecReload=/usr/bin/systemctl kill -s HUP %n" instead makes
it working as expected:

$ lpadmin -p test -v socket://test -D test -E
$ systemctl reload smb.service
$ while [ true ]; do
>   date
>   rpcclient localhost -U printadmin%printadmin -c 'enumprinters' | grep test
>   sleep 1
> done
Sa 16. Apr 21:09:24 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
Sa 16. Apr 21:09:25 CEST 2016
	name:[\\LOCALHOST\test]
	description:[\\LOCALHOST\test,,test]
^C
$ 

Version-Release number of selected component (if applicable):
samba-4.2.10-6.el7_2

How reproducible:
Everytime, see above and below.

Actual results:
Enabling spoolssd avoids pcap_cache_reload() during "systemctl reload 
smb.service" (until next housekeeping every 60 seconds).

Expected results:
Working pcap_cache_reload() during "systemctl reload smb.service" even
when spoolssd is enabled.

Additional info:
While this is not directly a bug in upstream Samba, it is a bug within
the systemd unit file as shipped with Samba in RHEL and Fedora.
Comment 2 Robert Scheck 2016-04-17 00:08:33 UTC 
Cross-filed case 01618854 on the Red Hat customer portal.
Comment 3 Andreas Schneider 2016-06-08 13:21:40 UTC 
That should be fixed by the rebase to Samba 4.4.4 looking at the code.
Comment 5 Andreas Schneider 2016-06-08 13:24:52 UTC 
Only the background queue reloads the pcap cache and it has a sighup handler.
Comment 6 Robert Scheck 2016-06-08 13:27:45 UTC 
What does this mean? RHEL 7.3 with Samba 4.4.x including a fix for the issue?
Comment 10 errata-xmlrpc 2016-11-04 07:00:33 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2016-2468.html
Note You need to log in before you can comment on or make changes to this bug.