Re: [PATCH] tick/sched: check skew_tick kernel parameter's validity

[Frederic Weisbecker]

Hi,

Le Sat, Aug 29, 2026 at 11:25:35PM +0300, Sergey Shtylyov a écrit :
> In skew_tick(), the result of get_option() call is ignored, so even if a
> value of the skew_tick kernel parameter was not specified (or specified
> as a list or range), the kernel won't complain. Add the missing check...
> 
> Found by Linux Verification Center (linuxtesting.org) with the Svace static
> analysis tool.
> 
> Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxxxxxxxx>
> 
> ---
> The patch is against the timers/nohz branch of the tip.git repo...
> 
>  kernel/time/tick-sched.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
> index c1ee0b256445..34ceccdd49b5 100644
> --- a/kernel/time/tick-sched.c
> +++ b/kernel/time/tick-sched.c
> @@ -1483,7 +1483,8 @@ static int sched_skew_tick;
>  
>  static int __init skew_tick(char *str)
>  {
> -	get_option(&str, &sched_skew_tick);
> +	if (get_option(&str, &sched_skew_tick) != 1)
> +		return -EINVAL;
>  
>  	return 0;

I'm not sure that matters. Initcall return values seem to be ignored on boot.
Looks like only modules do care.

Thanks.

>  }
> -- 
> 2.55.0

-- 
Frederic Weisbecker
SUSE Labs