Re: [PATCH v2 1/3] dm-inlinecrypt: Add inline encryption support

Christoph Hellwig
2024-10-18T05:56:42Z

On Fri, Oct 18, 2024 at 01:44:19AM -0400, Adrian Vovk wrote:
> > So just run a target on each partition.
>
>
> That has different semantics. If I encrypt each virtual partition there's
> nothing encrypting the metadata around the virtual partitions. Of course,
> this is a rather contrived example but point stands, the semantics are
> different.

Then you set up an dm-crype device mapper table for the partition table as
well.

> > This is the prime example of why allowing higher layers to skip
> > encryption is a no-go.
> >
>
> In what way does that break the file system's security model? Could you
> elaborate on what's objectionable about the behavior here?

Because you are now bypassing encryption for certainl LBA ranges in
the file system based on hints/flags for something sitting way above
in the stack.