Nightly regression with set_profile

[mwobensmith]

Sometime over the weekend, Nightly regressed with the following error in the canary:

2017-08-07 19:35:46 CRITICAL Reader tlscanary.xpcshell_worker Invalid output from worker <subprocess.Popen object at 0x7f74e3876410>: [Exception... "Component returned failure code: 0x80570018 (NS_ERROR_XPC_BAD_IID) [nsIJSCID.createInstance]" nsresult: "0x80570018 (NS_ERROR_XPC_BAD_IID)" location: "JS frame :: /home/ubuntu/tls-canary/tlscanary/js/scan_worker.js :: set_profile :: line 62" data: no]

It's a fatal error and I can't cancel the process via ctrl-c. Had to reboot. This is on both Mac and Linux.

Beta is fine. Need to diagnose why this fails, will do so shortly.

[mwobensmith]

This is an uncaught JavaScript exception on line 62 in scan_worker.js:

let file = Cc["@mozilla.org/file/local;1"]
.createInstance(Ci.nsILocalFile);

It was then logged by lines 26-37 in xpcshell_worker.py because the exception didn't match any known worker message.

When I run scan_worker.js by itself on Nightly via --xpcshell, it's fine. I captured all of the commands from a previous run and ran them one-by-one as stdin, but no issues.

I searched the web for this error but didn't find much. It regressed sometime over the weekend, as it was working as of Friday, 4 August, I believe.

I'm a bit at a loss. If you can take a look at it, maybe you might find out more. If we can't figure out what causes this in the next day or so, I will look for the build that regressed, find the changelist and file a bug.

[cr]

I am beginning to suspect that this might be sandbox-related. I dearly hope it is not.

[cr]

It's probably not sandbox, because the error occurs before even a file is touched. It is quite clearly a regression. Filed http://bgz.la/1388689 and hoping for the best.

[cr]

This is going into an emergency v3.1.2 release today.

[mwobensmith]

Ugh. My local build of Nightly was not updating, so I was testing against a build from 4 August. Hence, no errors when testing locally.

Thank you so much for figuring this out.

[cr]

125 has landed