docker version:
Client:
Version: 1.9.1
API version: 1.21
Go version: go1.4.2
Git commit: a34a1d5/1.9.1
Built:
OS/Arch: linux/amd64

Server:
Version: 1.9.1
API version: 1.21
Go version: go1.4.2
Git commit: a34a1d5/1.9.1
Built:
OS/Arch: linux/amd64

docker info:
Containers: 3
Images: 96
Server Version: 1.9.1
Storage Driver: devicemapper
Pool Name: docker-202:1-263200-pool
Pool Blocksize: 65.54 kB
Base Device Size: 107.4 GB
Backing Filesystem:
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 2.438 GB
Data Space Total: 107.4 GB
Data Space Available: 28.15 GB
Metadata Space Used: 5.857 MB
Metadata Space Total: 2.147 GB
Metadata Space Available: 2.142 GB
Udev Sync Supported: true
Deferred Removal Enabled: false
Deferred Deletion Enabled: false
Deferred Deleted Device Count: 0
Data loop file: /var/lib/docker/devicemapper/devicemapper/data
Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
Library Version: 1.02.93-RHEL7 (2015-01-28)
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 4.1.13-19.31.amzn1.x86_64
Operating System: Amazon Linux AMI 2015.09
CPUs: 2
Total Memory: 3.679 GiB

environment details:
aws ecs optimised amazon linux 2015.09f 64 bit
root volume: 30gb
ebs /dev/xvdb: 100gb - formatted using

mkfs -t ext4 /dev/xvdb

docker container is ubuntu 14.04, updated as part of image creation

steps to reproduce:
mount an ebs volume as /tmp inside a docker container

expected results
/ would show as default container size of 10gb

received result
/ shows as 100gb
df -h output:

Filesystem                                                                                        Size  Used Avail Use% Mounted on
/dev/mapper/docker-202:1-263200-e439740dba834851711b11743f9e63368e53b683a734352612dd374d41646e69  100G  1.2G   99G   2% /
tmpfs                                                                                             1.9G     0  1.9G   0% /dev
tmpfs                                                                                             1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/xvdb                                                                                          99G   60M   94G   1% /tmp
/dev/xvda1                                                                                         30G  3.2G   27G  11% /etc/hosts
shm                                                                                                64M     0   64M   0% /dev/shm