Re: [PATCH] x86/ima: require signed kernel modules

From: Seth Forshee
Date: Tue Feb 05 2019 - 10:19:07 EST

On Thu, Jan 31, 2019 at 02:18:59PM -0500, Mimi Zohar wrote:
> Require signed kernel modules on systems with secure boot mode enabled.
> To coordinate between appended kernel module signatures and IMA
> signatures, only define an IMA MODULE_CHECK policy rule if
> CONFIG_MODULE_SIG is not enabled.
> This patch defines a function named set_module_sig_required() and renames
> is_module_sig_enforced() to is_module_sig_enforced_or_required(). The
> call to set_module_sig_required() is dependent on CONFIG_IMA_ARCH_POLICY
> being enabled.
> Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>

With respect to interactions with the kernel lockdown patches, this
looks better than the patches I saw previously. I don't feel like I know
enough about what's going on with IMA to ack the patch, but I feel
confident that it's at least not going to break signature enforcement
for us.