RE: [PATCH] sysctl: add bound to panic_timeout to prevent overflow

[charley.ashbringer]

> On Thu, Jul 09, 2020 at 08:31:39PM -0700, Randy Dunlap wrote:
> > > +/* this is needed for setting boundery for panic_timeout to prevent
> > > +it from overflow*/
> >
> >                                  boundary (or max value)
overflow */
> >
> > > +static int panic_time_max = INT_MAX / 1000;
> 
> Or just simplify the comment.
> 
> /* Prevent overflow in panic() */
> 
> Or perhaps better, fix panic() to not overflow.
> 
> -		for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP)
{
> +		for (i = 0; i / 1000 < panic_timeout; i += PANIC_TIMER_STEP)
{
> 
> you probably also want to change i to be a long long or the loop may never
> terminate.

Thanks for the feedback, I too agree this should be better than 
modifying the sysctl, considering how localized and neat this
change is. It's also more readable. Setting a bound in sysctl.c
which is dependent on the constant value in panic.c is not a very
good idea.

I agree changing i from long to long long is necessary. 

I'll submit a v2 patch enforcing this shortly.

Cheers,
Changming