allow writing to systemd journal sockets

dino99, thank you for reporting this and helping make Ubuntu better. Did this problem not occur in a release prior to Vivid?

@Christopher

if you take the liberty to erase/modify my own reported details, then ask stupid questions, its up to you. Right now im agreeing what others are thinking about what you are doing here: adding confusion and spamming. So better to roll out and do your own learning job first.

dino99, unfortunately, it did not mention in your original Bug Description if this is reproducible in a prior release or not. As well, it was filled with speculation, and let alone grammar mistakes. Hence, please do not be rude, nor revert my edits, as this just simply delays your problem from getting addressed.

For more on this, please read https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette .

back to roots lp:241781
setting that report as "Low" priority is of course the smartest way to get it fixed.

found inside syslog:

Dec 15 06:11:25 u32 kernel: [ 2109.829779] audit: type=1400 audit(1418620285.127:81): apparmor="DENIED" operation="sendmsg" info="Failed name lookup - disconnected path" error=-13 profile="/usr/sbin/cupsd//third_party" name="run/systemd/journal/dev-log" pid=10965 comm="hpcups" requested_mask="w" denied_mask="w" fsuid=7 ouid=0
Dec 15 06:11:25 u32 systemd[1]: Cannot add dependency job for unit systemd-vconsole-setup.service, ignoring: Unit systemd-vconsole-setup.service failed to load: No such file or directory.
Dec 15 06:11:25 u32 systemd[1]: Started CUPS Printing Service.
Dec 15 06:11:25 u32 kernel: [ 2109.833523] Did not find alt setting 1 for intf 0, config 1
Dec 15 06:11:25 u32 systemd[1]: Cannot add dependency job for unit systemd-vconsole-setup.service, ignoring: Unit systemd-vconsole-setup.service failed to load: No such file or directory.

*********apparmor="DENIED" *********** is it expected ?

Please run the command

sudo aa-complain cupsd

in a terminal window and try whether this makes the problem going away.

See also the section "AppArmor Protection of the printing system" on https://wiki.ubuntu.com/DebuggingPrintingProblems

hi Till,

did set to 'complain' mode then rebooted: that indeed silence the #6 from syslog.
now only get:
 systemd[1]: Starting CUPS Printing Service...
Dec 15 14:44:52 u32 systemd[1]: Started CUPS Printing Service.

Does it only silence the warning or does it also solve your originally reported problem?

@Till

some more tests:
- the pc was already running, but the printer's usb cord was unplugged. So i plug it again, then set the printer 'on' via its on/off switch button. Start a printing job: done as expected.

- then let the printer plugged (usb cord) but the printer powerded down (on/off printer button)
- wait about 15 mn without printing
- then powered on the printer and try to print something again to test the previous 'usb port not awaken' issue reported here. The printing job have been done as expected.

To conclude about that report: the apparmor 'enforce' status seems the only one to be blamed, as the 'complain' status set let the usb port active. The 'hplip' report (lp:241781) seems also refer to the same apparmor config issue. Note that i've declared a false positive about the missing job inside the queue; sorry about that.

writing to the journal socket should be added to an abstraction the same as writing to /dev/log

Indeed I think we should fix that in /etc/apparmor.d/abstractions/base: That's the location that allows programs to write to /dev/log, so we sohuld also allow writing to /run/systemd/journal/{socket,dev-log}. Under systemd, /dev/log is just a symlink to /run/systemd/journal/dev-log, and /socket is the "native" journal protocol.

lp:612900 possibly the same reason (permission denied)

> Indeed I think we should fix that in /etc/apparmor.d/abstractions/base

AppArmor upstream appear to have made this change in r2850, LP:1413232.