ubuntu-core-launcher apparmor denial when creating /tmp/snaps

[Michael Nelson]

...or "/tmp/snaps not writeable after installing webdm"

NOTE: Not sure if this is specific to webdm or when snappy installs any 'framework' before /tmp/snaps is created.

Steps to reproduce:
 1) 'sudo snappy install webdm' on a fresh snappy unit
 2) 'ls -al /tmp/snaps' - root only write perms
 3) 'sudo snappy install hello-world'
 4) 'hello-world.echo'

Expected result: "Hello World!"
Actual result: mkdir: cannot create directory ‘/tmp/snaps/hello-world.canonical’: Permission denied

Example: http://paste.ubuntu.com/11489267/

If hello-world is installed first (and so creates /tmp/snaps with ubuntu:ubuntu) then there's no issue: http://paste.ubuntu.com/11489189/

I found a reference to the issue on the mailing list, but didn't see an existing bug report although experienced the same issue today: https://lists.ubuntu.com/archives/snappy-devel/2015-May/000709.html

[Jamie Strandboge (jdstrand)]

This is because the launcher has this in its policy:
    /tmp/snap.*/ w,

It should have this instead:
    /tmp/snap{s,.*}/ w,

[Jamie Strandboge (jdstrand)]

This was fixed long ago and since then, the implementation changed. Marking Fix Released.