Re: [PATCH v2] sched: check user input value of sysctl_sched_time_avg

From: Luis R. Rodriguez
Date: Wed Sep 06 2017 - 15:50:34 EST


On Mon, Sep 04, 2017 at 03:54:23PM +0800, Ethan Zhao wrote:
> Peter,
>
>
> On 2017/9/4 15:49, Peter Zijlstra wrote:
> > On Sat, Sep 02, 2017 at 02:57:32PM +0800, Ethan Zhao wrote:
> > > diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> > > index 6648fbb..609bed2 100644
> > > --- a/kernel/sysctl.c
> > > +++ b/kernel/sysctl.c
> > > @@ -367,7 +367,7 @@ static int sysrq_sysctl_handler(struct ctl_table *table, int write,
> > > .data = &sysctl_sched_time_avg,
> > > .maxlen = sizeof(unsigned int),
> > > .mode = 0644,
> > > - .proc_handler = proc_dointvec,
> > > + .proc_handler = sched_time_avg_handler,
> > *sigh*, what's wrong with the below? Too easy?
>  :),  seems I walked zigzag several cycles to get the right point.

It sounds like negative values are not possible too, right? If so then
you can use proc_douintvec_minmax().

Luis