snap-confine dmesg error and snap hangs

[Chris MacNaughton]

I'm trying to add a snap to Alacritty, my fork is at https://github.com/chrismacnaughton/alacritty, but whenever I try to run the built snap, there is no response and a single line goes into dmesg:

[36099.006669] audit: type=1400 audit(1491825708.546:25990): apparmor="DENIED" operation="file_inherit" profile="/usr/lib/snapd/snap-confine" name="/dev/tty" pid=1337 comm="snap-confine" requested_mask="wr" denied_mask="wr" fsuid=1000 ouid=0

[Jamie Strandboge (jdstrand)]

This particular denial is typically caused by debugging output. I'll add this to the snap-confine profile, but in the meantime, can you add to /etc/apparmor.d/usr.lib.snapd.snap-confine:

/dev/tty rw,

then run:
sudo apparmor_parser -r /etc/apparmor.d/usr.lib.snapd.snap-confine

[Chris MacNaughton (chris.macnaughton)]

Adding this line removes the dmesg error, the snap still is unresponsive though

[Chris MacNaughton (chris.macnaughton)]

this super simple rust program also fails, but only in classic mode: https://is.gd/wDGfHt

[Michael Vogt (mvo)]

https://github.com/snapcore/snapd/pull/3161#pullrequestreview-31879751

[Jamie Strandboge (jdstrand)]

The apparmor denial fix is committed in master and should be in 2.24.