[snap] seccomp denials for syscall=314 on amd64

syscall=314 is sys_sched_setattr on amd64

This is probably harmless, but would require further investigation to confirm.

thunderbird itself seems to be working fine but the crashreport seemed to have other issues due to Apparmor:

Aug 3 12:02:04 sdeziel-lemur thunderbird_thunderbird.desktop[32515]: ExceptionHandler::GenerateDump cloned child 150187
Aug 3 12:02:04 sdeziel-lemur thunderbird_thunderbird.desktop[150187]: ExceptionHandler::WaitForContinueSignal waiting for continue signal...
Aug 3 12:02:04 sdeziel-lemur thunderbird_thunderbird.desktop[32515]: ExceptionHandler::SendContinueSignalToChild sent continue signal to child
Aug 3 12:02:04 sdeziel-lemur kernel: [13893.569377] audit: type=1400 audit(1659542524.386:509): apparmor="DENIED" operation="open" profile="snap.thunderbird.thunderbird" name="/proc/32515/environ" pid=150187 comm="thunderbird-bin" requested_mask="r" denied_mask="r" fsuid=1000 ouid=1000
Aug 3 12:02:04 sdeziel-lemur thunderbird_thunderbird.desktop[32711]: Exiting due to channel error.
Aug 3 12:02:04 sdeziel-lemur kernel: [13893.827373] audit: type=1326 audit(1659542524.642:510): auid=1000 uid=1000 gid=1000 ses=9 subj=? pid=150188 comm="crashreporter" exe="/snap/thunderbird/237/crashreporter" sig=0 arch=c000003e syscall=314 compat=0 ip=0x7e5f095e773d code=0x50000
Aug 3 12:02:07 sdeziel-lemur thunderbird_thunderbird.desktop[150188]: Failed to open curl lib from binary, use libcurl.so instead

Is the crash reporter failing to submit crash reports?
If so, it might be a similar issue to https://bugzilla.mozilla.org/show_bug.cgi?id=1732720, which was fixed by staging libcurl4 in the snap.

There are quite a few "pending" crash reports and one from the day I opened this bug so I'd say yes, it's failing to submit them:

sdeziel@sdeziel-lemur:~/snap/thunderbird/common/.thunderbird/Crash Reports/pending$ ls -ltr | tail
-rw------- 1 sdeziel sdeziel 2088424 May 27 14:04 5f6acf74-091e-649d-d405-8f515d115c43.dmp
-rw------- 1 sdeziel sdeziel 11518 May 27 14:04 5f6acf74-091e-649d-d405-8f515d115c43.extra
-rw------- 1 sdeziel sdeziel 1790080 Jun 2 12:07 36f475a4-a06d-805a-f37c-3537f767db0d.dmp
-rw------- 1 sdeziel sdeziel 12510 Jun 2 12:07 36f475a4-a06d-805a-f37c-3537f767db0d.extra
-rw------- 1 sdeziel sdeziel 1752936 Jun 30 09:27 42252ef9-1b81-6337-f078-a16915f5a550.dmp
-rw------- 1 sdeziel sdeziel 8111 Jun 30 09:27 42252ef9-1b81-6337-f078-a16915f5a550.extra
-rw-rw-r-- 1 sdeziel sdeziel 344429 Jul 26 13:34 44fcac7c-c079-c1c2-d25b-a421fdc9b60b.dmp
-rw------- 1 sdeziel sdeziel 9526 Jul 26 13:34 44fcac7c-c079-c1c2-d25b-a421fdc9b60b.extra
-rw------- 1 sdeziel sdeziel 1667280 Aug 3 12:02 09575f30-efa8-4267-8875-7c78e787f556.dmp
-rw------- 1 sdeziel sdeziel 11198 Aug 3 12:02 09575f30-efa8-4267-8875-7c78e787f556.extra

I can confirm that the crash reporter dialog doesn't submit crashes, and that the same fix that was used in firefox (stage libcurl) makes it work.

FTR, I used this trick to test-crash thunderbird: https://superuser.com/a/678426

i.e. input the following in the devtools console:

    Cu.import("resource://gre/modules/ctypes.jsm");
    let zero = new ctypes.intptr_t(8);
    let badptr = ctypes.cast(zero, ctypes.PointerType(ctypes.int32_t));
    badptr.contents;

The crash reporter is fixed with https://github.com/ubuntu/thunderbird/pull/2.

Awesome, thank you Olivier!