Messages in this thread | | | Date | Tue, 20 Feb 2018 15:17:05 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH 2/3] sysctl: Warn when a clamped sysctl parameter is set out of range |
| |
On Mon, 19 Feb 2018 11:53:50 -0500 Waiman Long <longman@redhat.com> wrote:
> Even with clamped sysctl parameters, it is still not that straight > forward to figure out the exact range of those parameters. One may > try to write extreme parameter values to see if they get clamped. > To make it easier, a warning with the expected range will now be > printed in the kernel ring buffer when a clamped sysctl parameter > receives an out of range value.
This assumes that do_proc_dointvec_minmax_conv() and do_proc_douintvec_minmax_conv() are only ever called by privileged userspace. Because we mustn't give unprivileged applications a way to spam the kernel logs.
That's presumably true in the case of the caller you just added, but I don't see what we can do to guarantee this in the future, so perhaps we should add some permission check to the pr_warn()?
| |