running privileged applications out of home is dirty. But it is the
situation we are in with user namespaces and app images as well. Ubuntu
will not ship a profile for a privileged executable in the users home or
a writable location of an unprivileged user. As this can be leveraged to
by-pass the restriction, or it requires us to expand user mediation in
such a way that user writable locations with profiles defined become
privileged. Atm we are not adding addition restriction to the user. This
allows the user to define a profile that allows by-passing the
restriction. A user opting to create a profile in a user writable
location is less dangerous as the location becomes non-standard so it
becomes harder to exploit. It also requires the user to take a
deliberate privileged action to add the profile.

Generally for the nsjail profile an attachment like

  @{HOME}/android-*/prebuilts/build-tools/linux-x86/bin/nsjail

is slightly better, but still not great. Atm it is very close to the
same, but there are improvements coming that will tighten @{HOME} to a
user specific kernel variable which will be better than /**.

The other way to handle this would be setting the security xattr and
using that as part of the attachment.

```
  sudo setfattr -n security.apparmor -v nsjail
```

and define the profile as something like (you can make the path more
specific if you want).

```
  profile nsjail /**/nsjail xattrs=(security.apparmor="nsjail") 
flags=(unconfined) {
```

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https://bugs.launchpad.net/bugs/2063976

Title:
  Apparmor breaking nsjail in AOSP

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