[
https://issues.apache.org/jira/browse/YARN-7197?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16242539#comment-16242539
]
Eric Yang commented on YARN-7197:
---------------------------------
[~jlowe] {quote}
If the whitelist only allows bindmounts to the same path as the host then I
think we're OK here, but if it doesn't then we need to address that.
{quote}
Most of the docker image is not a full Linux image. It is possible that system
admin provide ability to mount /etc/hadoop/conf to a path of image chosen
directory to read hadoop configuration. It would be better for us to support
mapping of different source to destination path.
If someone mounted {{/etc/shadow}}, {{/etc/passwd}}, {{/etc/group}} and
{{/etc/sudoers}} from their user home directory into container for privileges
escalation. They still need to defeat the following:
# Add sudo binary into the container image.
# Find a way to remove {{--cap-drop=ALL}} which we hard coded into
container-executor.
# Gain write access to outside world through a mounted location like HDFS.
Trusted registry protects 1. Container-executor binary protects 2. Allowed
white list protects 3. I think it's difficult to get a privilege escalation,
if the protections are in place. The original intend to protect QA users from
destroying cluster hosts and giving them access to spawn root container is a
noble cause. However, I don't think we will find a right way to protect root
from root using black list. {{--cap-drop=ALL}} is the better way to give them
container root power and keep that access within the container. I will leave
this JIRA open for others to try.
> Add support for a volume blacklist for docker containers
> --------------------------------------------------------
>
> Key: YARN-7197
> URL: https://issues.apache.org/jira/browse/YARN-7197
> Project: Hadoop YARN
> Issue Type: Sub-task
> Components: yarn
> Reporter: Shane Kumpf
> Assignee: Eric Yang
> Attachments: YARN-7197.001.patch, YARN-7197.002.patch,
> YARN-7197.003.patch, YARN-7197.004.patch, YARN-7197.005.patch
>
>
> Docker supports bind mounting host directories into containers. Work is
> underway to allow admins to configure a whilelist of volume mounts. While
> this is a much needed and useful feature, it opens the door for
> misconfiguration that may lead to users being able to compromise or crash the
> system.
> One example would be allowing users to mount /run from a host running
> systemd, and then running systemd in that container, rendering the host
> mostly unusable.
> This issue is to add support for a default blacklist. The default blacklist
> would be where we put files and directories that if mounted into a container,
> are likely to have negative consequences. Users are encouraged not to remove
> items from the default blacklist, but may do so if necessary.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
