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From:   ebiederm@xmission.com (Eric W. Biederman)
To:     "Darrick J. Wong" <darrick.wong@oracle.com>
Cc:     "Theodore Y. Ts'o" <tytso@mit.edu>,
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Date:   Fri, 10 Aug 2018 20:32:04 -0500
In-Reply-To: <20180811003852.GA10463@magnolia> (Darrick J. Wong's message of
        "Fri, 10 Aug 2018 17:38:52 -0700")
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Subject: Re: BUG: Mount ignores mount options
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"Darrick J. Wong" <darrick.wong@oracle.com> writes:

> On Fri, Aug 10, 2018 at 07:54:47PM -0400, Theodore Y. Ts'o wrote:

>> The reason why I bring this up here is that in container land, there
>> are those who believe that "container root" should be able to mount
>> file systems, and if the "container root" isn't trusted, the fact that
>> the "container root" can crash the host kernel, or worse, corrupt the
>> host kernel and break out of the container as a result, that would be
>> sad.
>> 
>> I was pretty sure most file system developers are on the same page
>> that allowing untrusted "container roots" the ability to mount
>> arbitrary block device file systems is insanity.
>
> Agreed.

For me I am happy with fuse.  That is sufficient to cover any container
use cases people have.   If anyone comes bugging you for more I will be
happy to push back.

The only thing that containers have to do with this is I wind up
touching a lot of the kernel/user boundary so I get to see a lot of it
and sometimes see weird things.

Eric