Re: [PATCH for Xen 4.5 v2 1/2] xen: sanity check input and serialization in sched_rt.c

[George Dunlap <george.dunlap@eu.citrix.com>]

On 10/25/2014 03:16 PM, Meng Xu wrote:
> Sanity check input params in rt_dom_cntl();
> Serialize rt_dom_cntl() against the global lock.
>
> Signed-off-by: Meng Xu <mengxu@cis.upenn.edu>

Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com>

Thanks,
  -George

> ---
>   xen/common/sched_rt.c |    9 +++++++++
>   1 file changed, 9 insertions(+)
>
> diff --git a/xen/common/sched_rt.c b/xen/common/sched_rt.c
> index 6c8faeb..b87c95b 100644
> --- a/xen/common/sched_rt.c
> +++ b/xen/common/sched_rt.c
> @@ -1042,9 +1042,11 @@ rt_dom_cntl(
>       struct domain *d,
>       struct xen_domctl_scheduler_op *op)
>   {
> +    struct rt_private *prv = rt_priv(ops);
>       struct rt_dom * const sdom = rt_dom(d);
>       struct rt_vcpu *svc;
>       struct list_head *iter;
> +    unsigned long flags;
>       int rc = 0;
>   
>       switch ( op->cmd )
> @@ -1055,12 +1057,19 @@ rt_dom_cntl(
>           op->u.rtds.budget = svc->budget / MICROSECS(1);
>           break;
>       case XEN_DOMCTL_SCHEDOP_putinfo:
> +        if ( op->u.rtds.period == 0 || op->u.rtds.budget == 0 )
> +        {
> +            rc = -EINVAL;
> +            break;
> +        }
> +        spin_lock_irqsave(&prv->lock, flags);
>           list_for_each( iter, &sdom->vcpu )
>           {
>               struct rt_vcpu * svc = list_entry(iter, struct rt_vcpu, sdom_elem);
>               svc->period = MICROSECS(op->u.rtds.period); /* transfer to nanosec */
>               svc->budget = MICROSECS(op->u.rtds.budget);
>           }
> +        spin_unlock_irqrestore(&prv->lock, flags);
>           break;
>       }
>