1183858 - The purge-builds mozharness can delete a users home folder

Status: RESOLVED INVALID

(Release Engineering :: Applications: MozharnessCore, defect)

Description

[Chris Manchester (limited bugmail, email directly)]

I was running

python scripts/scripts/firefox_ui_updates.py --cfg generic_releng_config.py --firefox-ui-branch mozilla-beta --update-verify-config mozBeta-firefox-linux.cfg --tools-tag FIREFOX_40_0b4_RELEASE_RUNTIME --total-chunks 6 --this-chunk 1

in order to reproduce the failure in bug 1176358. There's a purge-builds step that runs, and succeeds in the following:

14:09:53     INFO - #####
14:09:53     INFO - ##### Running purge-builds step.
14:09:53     INFO - #####
14:09:53     INFO - Running main action method: purge_builds
14:09:53     INFO - Running command: ['/home/chris/mozharness/external_tools/purge_builds.py', '-s', '2', '--max-age', '14', '--not', 'info', '--not', 'rel-*', '--not', 'tb-rel-*', '/home/chris']
14:09:53     INFO - Copy/paste: /home/chris/mozharness/external_tools/purge_builds.py -s 2 --max-age 14 --not info --not rel-* --not tb-rel-* /home/chris
14:09:53     INFO - Using env: {'PATH': '/home/chris/git-cinnabar:/usr/local/heroku/bin:/home/chris/B2G/out/host/linux-x86/bin:/home/chris/.cabal/bin:/home/chris/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games'}

<snip>

14:12:34     INFO -  Deleting /home/chris/Documents
14:12:34     INFO -  Deleting /home/chris/Music
14:12:34     INFO -  Deleting /home/chris/Public
14:12:34     INFO -  Deleting /home/chris/Templates
14:12:34     INFO -  Deleting /home/chris/Videos

<snip>

14:12:34     INFO -  Deleting /home/chris/.pip
14:12:34     INFO -  Deleting /home/chris/.ssh
14:12:34     INFO -  Deleting /home/chris/.cabal

etc.

Fortunately I don't keep anything important on my laptop that isn't in version control, but wow.

Comment 1

[Jordan Lund (:jlund)]

wow...

so purge_builds considers anything free game from the base_work_dir: http://mxr.mozilla.org/build/source/mozharness/mozharness/mozilla/purge.py#48

in your case that's '/home/chris' from the looks of your purge_builds.py call in comment 0

base_work_dir defaults to os.cwd() or .. wherever you call mozharness from. So i think you must have ran:
    python mozharness/scripts/firefox_ui_updates.py from /home/chris

This seems pretty fragile. It supports how we do things in automation right now but maybe we should change base_work_dir to work_dir and only purge things within 'build'. In your case, that would have been anything in /home/chris/build/* and not one level back. Though, I can't quite grasp the effect that would have in automation.

armen: iirc - you have been conscious of running this locally. How do we run it locally and is there a way we can remove purge_build action from the list of actions?

Comment 2

[Jordan Lund (:jlund)]

catlee tells me that purge_builds.py will actually crawl up one (maybe two?) directories from the target path its given as that's how folders/builddirs are structured in buildbot automation.

safest thing to do would be to remove this action when run locally and always run mh from a nested location from anything important.

Comment 3

[Armen [:armenzg]]

The purging was added since the Windows builders are not by default cleaned up properly by anything (maybe runner is now in effect and this might not be an issue).

I backed this out for now until someone has time to look into it:
https://hg.mozilla.org/build/mozharness/rev/0dc76e63c4a6

Takers to fix the root issue are welcome. I don't have time at the moment and purging builds is not a hard requirement for me.

Comment 4

[Armen [:armenzg]]

I've made this block bug 1182796 (make it production ready) instead of bug 1176358 (determine why Linux jobs are crashing).

Comment 5

[Armen [:armenzg]]

We don't have the purge builds step anymore. I'm not planning on adding it unless really needed.
We clean up the machines without purge-builds before running the actual job.
I don't know why there is purge-builds to beging with.