Re: [PATCH V2 01/10] Secure boot: Add new capability

From: Serge Hallyn
Date: Thu Sep 27 2012 - 23:11:18 EST


Quoting 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.
>
> Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx>

Acked-by: Serge E. Hallyn <serge.hallyn@xxxxxxxxxx>

> ---
> include/linux/capability.h | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/capability.h b/include/linux/capability.h
> index d10b7ed..4345bc8 100644
> --- a/include/linux/capability.h
> +++ b/include/linux/capability.h
> @@ -364,7 +364,11 @@ struct cpu_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)
>
> --
> 1.7.11.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.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/