Re: [PATCH 08/18] Secure boot: Add new capability

From: Pavel Machek
Date: Sun Aug 25 2013 - 12:14:36 EST


On Thu 2013-08-22 19:01:47, Lee, Chun-Yi wrote:
> From: Matthew Garrett <mjg@xxxxxxxxxx>
>
> Secure boot adds certain policy requirements, including that root must not
> be able to do anything that could cause the kernel to execute arbitrary code.
> The simplest way to handle this would seem to be to add a new capability
> and gate various functionality on that. We'll then strip it from the initial
> capability set if required.

There was some discussion about this before, right? And I don't think
conclusion was it was acceptable...?

> Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx>
> Acked-by: Lee, Chun-Yi <jlee@xxxxxxxx>
> Signed-off-by: Lee, Chun-Yi <jlee@xxxxxxxx>
> ---
> include/uapi/linux/capability.h | 6 +++++-
> 1 files changed, 5 insertions(+), 1 deletions(-)
>
> diff --git a/include/uapi/linux/capability.h b/include/uapi/linux/capability.h
> index ba478fa..7109e65 100644
> --- a/include/uapi/linux/capability.h
> +++ b/include/uapi/linux/capability.h
> @@ -343,7 +343,11 @@ struct vfs_cap_data {
>
> #define CAP_BLOCK_SUSPEND 36
>
> -#define CAP_LAST_CAP CAP_BLOCK_SUSPEND
> +/* Allow things that trivially permit root to modify the running kernel */
> +
> +#define CAP_COMPROMISE_KERNEL 37
> +
> +#define CAP_LAST_CAP CAP_COMPROMISE_KERNEL
>
> #define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)
>

--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/