Profiles that have an undecidable overlap in their attachments are
being incorrectly handled. Instead of failing to attach the first one
encountered is being used.
eg.
profile A /** { .. }
profile B /*foo { .. }
have an unresolvable longest left attachment, they both have an exact
match on / and then have an overlapping expression that has no clear
winner.
Currently the winner will be the profile that is loaded first which
can result in non-deterministic behavior. Instead in this situation
the exec should fail.
Fixes: 898127c34e ("AppArmor: functions for domain transitions")
Signed-off-by: John Johansen <john.johansen@canonical.com>