fix: spark.url file mode must be 0644

[richm]

The other files in /etc/pcp/openmetrics/ are all 0644. The latest
pmdaopenmetrics service will get a permission denied trying to open spark.url
without this mode change.

Signed-off-by: Rich Megginson [email protected]

[natoscott]

LGTM, you could maybe tweak the commit message a little (s/pmcd/pmdaopenmetrics/g) if you like, but I'm sure people will get the gist as-is too.

[richm]

pmdaopenmetrics was recently changed to run 'unprivileged' (under the 'pcp' user account) - previously it ran as root - this is some unintended fallout (and unforeseen, I'm wondering if that change might affect anything else now - its the first diagnosed case of this I've seen fortunately, so hopefully this isn't common).

@natoscott does this mean we should keep the permissions at 0600 for older versions of pmdaopenmetrics? If so, which version has the change?

[natoscott]

pmdaopenmetrics was recently changed to run 'unprivileged' (under the 'pcp' user account) - previously it ran as root - this is some unintended fallout (and unforeseen, I'm wondering if that change might affect anything else now - its the first diagnosed case of this I've seen fortunately, so hopefully this isn't common).

@natoscott does this mean we should keep the permissions at 0600 for older versions of pmdaopenmetrics?

There's no reason to do so I can think of - root can read it either way and its not sensitive information.

If so, which version has the change?

This is the relevant changelog entry for upstream pcp-6.3.2:
https://github.com/performancecopilot/pcp/blob/87920ab31083f3e7bc10de498f78da26534ce7e8/CHANGELOG#L114

Not sure which RHEL releases this has been back-ported to off the top of my head.