Description of problem: there is some strange error about avahi? dbus? when printing, no idea why its connected Version-Release number of selected component (if applicable): firefox-52.5.1-1.el7_4.x86_64 dbus-1.10.24-3.el7.x86_64 avahi-0.6.31-19.el7.x86_64 cups-1.6.3-35.el7.x86_64 How reproducible: tried once, and its always there Steps to Reproduce: 1. rhe75 nightly, server with GUI, all default 2. add usb printer 3. firefox + print whatever page 4, I did no setup of avahi, its all by default Actual results: log shows some error: Jan 15 11:06:31 localhost dbus[689]: [system] Rejected send message, 0 matched rules; type="method_return", sender=":1.2" (uid=70 pid=686 comm="avahi-daemon: starting up ") interface="(unset)" member="(unset)" error name="(unset)" requested_reply="0" destination=":1.434" (uid=0 pid=3762 comm="/usr/lib64/firefox/firefox ") Jan 15 11:06:31 localhost dbus[689]: [system] Rejected send message, 0 matched rules; type="method_return", sender=":1.2" (uid=70 pid=686 comm="avahi-daemon: starting up ") interface="(unset)" member="(unset)" error name="(unset)" requested_reply="0" destination=":1.434" (uid=0 pid=3762 comm="/usr/lib64/firefox/firefox ") Expected results: log is without error in case of default installation Additional info:
error appears at each printing page so log seems to be full of these errors.
(In reply to Petr Sklenar from comment #0) > Jan 15 11:06:31 localhost dbus[689]: [system] Rejected send message, 0 > matched rules; type="method_return", sender=":1.2" (uid=70 pid=686 > comm="avahi-daemon: starting up ") interface="(unset)" member="(unset)" > error name="(unset)" requested_reply="0" destination=":1.434" (uid=0 > pid=3762 comm="/usr/lib64/firefox/firefox ") Hmm, I don't understand why would dbus reject avahi to send method_return message. According to avahi's dbus policy, you can either send a message to avahi (unless the message is SetHostName method call and you are not root or in avahi group), in which case you should be allowed to receive the return or you can't send the message in the first place. David, do you have any explanation for above log message?
I was able to figure out the root cause. Problem is that avahi client (GNOME print dialog -- the issue is not specific to Firefox, evince and gedit have the same problem) calls Free() method on ServerBrowser object and in the method_call message it sets NO_REPLY_EXPECTED flag. However, avahi didn't respect the flag (avahi was written around the same time when dbus-daemon and NO_REPLY_EXPECTED flag was a newer addition to the dbus spec and daemon) and sent method_reply (OK) anyway. Our new dbus-daemon (rebased in RHEL-7.5) doesn't like that so it dropped the message and logged an error. This is not the new problem, also Fedora has the same issue.
Created attachment 1386189 [details] Proposed patch
Patch posted upstream, https://github.com/lathiat/avahi/pull/165
fedora bug: Bug 1540180
Patch still waiting for acceptance to upstream.
Upstream PR has been finally merged so we can move forward with the RHEL fix.
After evaluating this issue, there are no plans to address it further or fix it in an upcoming release. Therefore, it is being closed. If plans change such that this issue will be fixed in an upcoming release, then the bug can be reopened.