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

From: Jeremy Cline
Date: Mon May 11 2020 - 09:42:37 EST


On Sat, Feb 22, 2020 at 03:51:24AM +1100, James Morris wrote:
> 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?
>

Can we take resounding silence as no objections?

- Jeremy

> > ---
> > 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>
>