Re: [PATCH] lockdown: Allow unprivileged users to see lockdown status

From: James Morris
Date: Fri Feb 21 2020 - 11:51:45 EST


On Thu, 20 Feb 2020, Jeremy Cline wrote:

> A number of userspace tools, such as systemtap, need a way to see the
> current lockdown state so they can gracefully deal with the kernel being
> locked down. The state is already exposed in
> /sys/kernel/security/lockdown, but is only readable by root. Adjust the
> permissions so unprivileged users can read the state.
>
> Fixes: 000d388ed3bb ("security: Add a static lockdown policy LSM")
> Cc: Frank Ch. Eigler <fche@xxxxxxxxxx>
> Signed-off-by: Jeremy Cline <jcline@xxxxxxxxxx>

Looks fine to me, any objection from Matthew or others?

> ---
> security/lockdown/lockdown.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/security/lockdown/lockdown.c b/security/lockdown/lockdown.c
> index 5a952617a0eb..87cbdc64d272 100644
> --- a/security/lockdown/lockdown.c
> +++ b/security/lockdown/lockdown.c
> @@ -150,7 +150,7 @@ static int __init lockdown_secfs_init(void)
> {
> struct dentry *dentry;
>
> - dentry = securityfs_create_file("lockdown", 0600, NULL, NULL,
> + dentry = securityfs_create_file("lockdown", 0644, NULL, NULL,
> &lockdown_ops);
> return PTR_ERR_OR_ZERO(dentry);
> }
>

--
James Morris
<jmorris@xxxxxxxxx>