Signed-off-by: NJohn Johansen <john.johansen@canonical.com>

namespaces now completely use the unconfined profile to track the
refcount and rcu freeing cycle. So rework the code to simplify (track
everything through the profile path right up to the end), and move the
rcu_head from policy base to profile as the namespace no longer needs
it.
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Acked-by: NSeth Arnold <seth.arnold@canonical.com>

ns->unconfined is being used read side without locking, nor rcu but is
being updated when a namespace is removed. This works for the root ns
which is never removed but has a race window and can cause failures when
children namespaces are removed.

Also ns and ns->unconfined have a circular refcounting dependency that
is problematic and must be broken. Currently this is done incorrectly
when the namespace is destroyed.

Fix this by forward referencing unconfined via the replacedby infrastructure
instead of directly updating the ns->unconfined pointer.

Remove the circular refcount dependency by making the ns and its unconfined
profile share the same refcount.
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Acked-by: NSeth Arnold <seth.arnold@canonical.com>

remove the use of replaced by chaining and move to profile invalidation
and lookup to handle task replacement.

Replacement chaining can result in large chains of profiles being pinned
in memory when one profile in the chain is use. With implicit labeling
this will be even more of a problem, so move to a direct lookup method.
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>

Signed-off-by: NJohn Johansen <john.johansen@canonical.com>

The sid is not going to be a direct property of a profile anymore, instead
it will be directly related to the label, and the profile will pickup
a label back reference.

For null-profiles replace the use of sid with a per namespace unique
id.
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Acked-by: NKees Cook <kees@ubuntu.com>

Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Acked-by: NSteve Beattie <sbeattie@ubuntu.com>

Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>

Add the base support for the new policy extensions. This does not bring
any additional functionality, or change current semantics.
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Acked-by: NKees Cook <kees@ubuntu.com>

The basic routines and defines for AppArmor policy.  AppArmor policy
is defined by a few basic components.
      profiles - the basic unit of confinement contain all the information
                 to enforce policy on a task

                 Profiles tend to be named after an executable that they
                 will attach to but this is not required.
      namespaces - a container for a set of profiles that will be used
                 during attachment and transitions between profiles.
      sids - which provide a unique id for each profile
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Signed-off-by: NJames Morris <jmorris@namei.org>