Re: [PATCH] tracing: do not leak kernel addresses

From: Steven Rostedt
Date: Fri Jul 27 2018 - 09:47:35 EST


On Fri, 27 Jul 2018 15:40:32 +0200
Jann Horn <jannh@xxxxxxxxxx> wrote:

> > > But the code doesn't go to dmesg. It's only available
> > > via /sys/kernel/debug/tracing/printk_formats which is only available
> > > via root. Nobody else has access to that directory.
> > >
> > > -- Steve
> >
> > I think the point was that when we take capabilities into account the root
> > privileges aren't unequivocal anymore. The 'root' owned process with only
> > 'CAP_SYSLOG' shouldn't have access to /sys/kernel/debug/tracing/printk_formats
>
> Then they shouldn't have access to debugfs at all, right?

That's what I'm thinking.

-- Steve