Bug 1656939

Summary: Incron causes defunct processes
Product: [Fedora] Fedora EPEL Reporter: Jay Leafey <jay.leafey>
Component: incronAssignee: Kevin Fenzi <kevin>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: epel7CC: andreas.dijkman, beaaegicfqmq6rykaqaakty3lqcg6btv, emsmith, it-techsupport, kevin, mattdm, maxime.hamon, me, nick.parrin, rbean, redhat-bugzilla, ruben, strobert
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Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: incron-0.5.12-9.fc28 incron-0.5.12-9.fc29 incron-0.5.12-9.el7 Doc Type: If docs needed, set a value
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Last Closed: 2019-01-16 01:42:34 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Jay Leafey 2018-12-06 17:13:15 UTC
Description of problem:

Since the update in EPEL to 0.5.12, every time incron handles a filesystem event it creates a "zombie" process.  This happens less frequently when the events are from the system incrontab files (/etc/incron.d/) but happens every single time when the event is from a user incrontab.

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

CentOS 7 (1810) (7.6)
incron 0.5.12-16

How reproducible:

Easily reproducible.

Steps to Reproduce:
1. Install the incron RPM from EPEL
2. Set up a user incrontab monitoring a specific directory:
/home/jleafey/incrontest	IN_CLOSE_WRITE	"$% detected on file $@/$#" | logger --priority user.notice

3. Count defunct processes before test
4. Create files in the monitored directory
5. Count defunct processes after test

Actual results:

An additional defunct process is created for every file created in the monitored directory.

Expected results:

No defunct processes would be created when monitored filesystem events were processed.

Additional info:


I have rebuilt incrond directly from the sources on Github and it does not cause the same behaviour, events get processed and no zombies are left.  I compared the build logs from the RPM build to the "raw" build and the options provide to G++ are different.

From "rpmbuild -bc":
g++ -c  -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches   -m64 -mtune=generic 

From "make":
g++ -c  -O2 -pedantic -std=c++11 -g0 -pipe -Wall -W -Wshadow -Wpointer-arith -Wwrite-strings -ffor-scope

Comment 1 Jay Leafey 2018-12-06 17:55:52 UTC
I was curious to see if this also occurred with the Fedora package, so I build a Fedora 29 server VM for testing.  I used exactly the same test case and got exactly the same results, using the packaged incron from Fedora's repositories causes a zombie process to be left after processing each filesystem event.  I have not tried building from source on the test system yet.

Comment 2 Robert Scheck 2018-12-28 11:03:46 UTC
From my point of view, this is a 0.5.12 issue (I'm also seeing massive memory leaks with 0.5.12 that did not exist with an identical configuration at 0.5.10).

Comment 3 Passur IT 2019-01-03 16:51:45 UTC
We are having this problem too on production systems.  After enough time and incron actions, it actually causes system issues.  Please back out this version for the time-being as it is clearly unstable.  I think that's the prudent thing to do until the package can be tested more.  Delays are only going to lead to more people having issues.

Comment 4 Kevin Fenzi 2019-01-05 19:57:15 UTC
Can you all please try this scratch build and see if the problem is fixed: 

https://koji.fedoraproject.org/koji/taskinfo?taskID=31840653

If that looks good, I will push an update (for epel7 and f29/f28 as the fix applies to them all)

Comment 5 Maxime HAMON 2019-01-07 14:18:23 UTC
Everything looks good for me. No more defunct process

Comment 6 Remco 2019-01-07 19:39:21 UTC
Works good for me on CentOS7 as well!

Comment 7 nick 2019-01-07 19:40:02 UTC
had the same issue, thanks for fixing this :)

Comment 8 Fedora Update System 2019-01-07 22:36:49 UTC
incron-0.5.12-9.fc29 has been submitted as an update to Fedora 29. https://bodhi.fedoraproject.org/updates/FEDORA-2019-bbc0a2c14a

Comment 9 Fedora Update System 2019-01-07 22:37:03 UTC
incron-0.5.12-9.el7 has been submitted as an update to Fedora EPEL 7. https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2019-60b62db475

Comment 10 Fedora Update System 2019-01-07 22:37:33 UTC
incron-0.5.12-9.fc28 has been submitted as an update to Fedora 28. https://bodhi.fedoraproject.org/updates/FEDORA-2019-75bfa8d4a2

Comment 11 Fedora Update System 2019-01-08 00:56:18 UTC
incron-0.5.12-9.fc28 has been pushed to the Fedora 28 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-75bfa8d4a2

Comment 12 Fedora Update System 2019-01-08 01:11:27 UTC
incron-0.5.12-9.el7 has been pushed to the Fedora EPEL 7 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2019-60b62db475

Comment 13 Fedora Update System 2019-01-08 02:05:13 UTC
incron-0.5.12-9.fc29 has been pushed to the Fedora 29 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-bbc0a2c14a

Comment 14 Jay Leafey 2019-01-08 17:47:11 UTC
I have installed incron-0.5.12-9.el7 from testing on one of the systems where the problem originally occurred.  After a couple of hours of testing I have seen no defunct processes.  I have tested both user and system incrontabs and so far have not seen any issues.

Comment 15 Matthew Miller 2019-01-11 15:41:39 UTC
Yes, I'm hitting this too -- I've installed the update and will test.

Comment 16 Fedora Update System 2019-01-16 01:42:34 UTC
incron-0.5.12-9.fc28 has been pushed to the Fedora 28 stable repository. If problems still persist, please make note of it in this bug report.

Comment 17 Fedora Update System 2019-01-16 02:19:34 UTC
incron-0.5.12-9.fc29 has been pushed to the Fedora 29 stable repository. If problems still persist, please make note of it in this bug report.

Comment 18 Fedora Update System 2019-02-12 02:55:50 UTC
incron-0.5.12-9.el7 has been pushed to the Fedora EPEL 7 stable repository. If problems still persist, please make note of it in this bug report.