docker exec failed on 1.6.2.003

hello

I have a problem to execute "docker exec -ti <progname> bash the message output is
"type=1400 audit(1443969471.682:30): apparmor="DENIED" operation="open" profile="docker_docker-daemon_1.6.2.003"
name="/" pid=<pid-#> comm="docker.x86_64" requested_mask="r" denied_mask="r" fsuid=0 ouid=0

How can I exec into a running container? even docker attach is hanging around,
appreciate any advice on that

I am running the latest snappy & updates

(amd64)ubuntu@localhost:~$ snappy info
release: ubuntu-core/15.04/stable
architecture: amd64
frameworks: docker, webdm
apps:

(amd64)ubuntu@localhost:~$ snappy list
Name Date Version Developer
ubuntu-core 2015-09-17 5 ubuntu
docker 2015-10-04 1.6.2.003 canonical
webdm 2015-09-17 0.9 canonical
generic-amd64 2015-09-17 1.4 canonical

(amd64)ubuntu@localhost:~$ docker info
Containers: 2
Images: 43
Storage Driver: aufs
 Root Dir: /var/lib/apps/docker/1.6.2.003/aufs
 Backing Filesystem: extfs
 Dirs: 47
 Dirperm1 Supported: true
Execution Driver: native-0.2
Kernel Version: 3.19.0-28-generic
Operating System: <unknown>
CPUs: 1
Total Memory: 741.1 MiB
Name: localhost.localdomain
ID: 7M25:QCMT:AQJM:X5HZ:PVLW:CK7A:4VYA:7CIP:GLOK:HXA7:UGV5:L2EI
WARNING: No swap limit support

(amd64)ubuntu@localhost:~$ docker version
Client version: 1.6.2
Client API version: 1.18
Go version (client): go1.4.2
Git commit (client): 8f2d6e5
OS/Arch (client): linux/amd64
Server version: 1.6.2
Server API version: 1.18
Go version (server): go1.4.2
Git commit (server): 8f2d6e5