[jail] Allowing root privledged users to renice

[Julian Elischer]

On 5/25/12 10:04 AM, Bjoern A. Zeeb wrote:
> On 25. May 2012, at 16:48 , Sean Bruno wrote:
>
>> I've been toying with the idea of letting jails renice processes ... how
>> dangerous and/or stupid is this idea?
>>
>> ==== //depot/yahoo/ybsd_9/src/sys/kern/kern_jail.c#5 -
>> /home/seanbru/ybsd_9/src/sys/kern/kern_jail.c ====
>> 270a271,275
>> + int   jail_allow_renice = 0;
>> + SYSCTL_INT(_security_jail, OID_AUTO, allow_renice, CTLFLAG_RW,
>> +&jail_allow_renice, 0,
>> +    "Prison root can renice processes");
>>
>> 3857a3863,3865
>> +      case PRIV_SCHED_SETPRIORITY:
>> +              if (!jail_allow_renice)
>> +                       return (EPERM);
>
> I think sysctls are a bad idea given jails have per-jail flags these days.
>
> Maybe also only allow re-nicing to be nicer but not less nice?
     ^^^^   for sure !  start a jail with it's max priority and the 
root within can allow nicer priorities only..
you can always add priority from teh master (parent) environment outside.

> /bz
>