A few things I neglected to mention that John reminded me of are

1. if the kernel changes its apparmor feature set or the apparmor parser
itself changes how it generates policy, we'll still be running the old
kernel and parser. This will happen on an upgrade from 15.04 to 16.04
for example. If the device tarball exported the apparmor feature set (it
can be mocked as a text file-- we do that for custom tarballs already
for example) then we can point the parser at that. Furthermore the
parser could be extracted from the tarball as part of the recompile
step.

Since most upgrades very-much-intentionally do not change the parser or
the feature set, I think the first iteration could avoid dealing with
the apparmor features file and the parser. The second iteration could
incorporate it.

2. Due to how profile caching is currently implemented, the recompiling
caches is a one way operation. In other words, if prior to reboot we
recompile all the policy that invalidates the old caches. If on reboot
the boot detects that a recompile is needed (eg, we got something wrong
before reboot-- eg, the kernel in the device tarball was updated but
someone forgot to update the mocked features file), then the recompile
will still happen on reboot. If the processes surrounding updates are
sufficient and QA is involved, this should be an avoidable situation.

3. The security team has worked on versioned policy caches in previous
cycles but the work is incomplete and deprioritized. Depending on how
things are ultimately implemented, its possible versioned policy caches
could help with the implementation. I think performing point '8' on
Touch and carefully handling the features file and parser changes, this
is probably not needed (there isn't a concept of rolling back on Touch
for example).

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1350598

Title:
  AppArmor policy compile improvements

To manage notifications about this bug go to:
https://bugs.launchpad.net/apparmor/+bug/1350598/+subscriptions

-- 
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to