On Sun, Jul 14, 2019 at 11:49:15AM -0700, Paul E. McKenney wrote:

On Sun, Jul 14, 2019 at 05:48:00PM +0300, Dmitry Vyukov wrote:

quoted

But short term I don't see any other solution than stop testing
sched_setattr because it does not check arguments enough to prevent
system misbehavior. Which is a pity because syzkaller has found some
bad misconfigurations that were oversight on checking side.
Any other suggestions?

Keep the times down to a few seconds?  Of course, that might also
fail to find interesting bugs.

Right, if syzcaller can put a limit on the period/deadline parameters
(and make sure to not write "-1" to
/proc/sys/kernel/sched_rt_runtime_us) then per the in-kernel
access-control should not allow these things to happen.