Re: [PATCH v4 0/3] initramfs: add support for xattrs in the initial ram disk

From: Mimi Zohar
Date: Mon Jul 01 2019 - 09:22:42 EST

On Thu, 2019-05-23 at 14:18 +0200, Roberto Sassu wrote:
> This patch set aims at solving the following use case: appraise files from
> the initial ram disk. To do that, IMA checks the signature/hash from the
> security.ima xattr. Unfortunately, this use case cannot be implemented
> currently, as the CPIO format does not support xattrs.
> This proposal consists in including file metadata as additional files named
> METADATA!!!, for each file added to the ram disk. The CPIO parser in the
> kernel recognizes these special files from the file name, and calls the
> appropriate parser to add metadata to the previously extracted file. It has
> been proposed to use bit 17:16 of the file mode as a way to recognize files
> with metadata, but both the kernel and the cpio tool declare the file mode
> as unsigned short.

Thanks, Roberto!

Victor, Taras, Rob, Arvind, Peter, if you're good with this latest
design, could we get some Reviewed-by, Acked-by, or Tested-by?