sched: Disallow sched_attr::sched_policy < 0

The scheduler uses policy=-1 to preserve the current policy state to
implement sys_sched_setparam(), this got exposed to userspace by
accident through sys_sched_setattr(), cure this.

Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140509085311.GJ30445@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra 2014-05-09 10:49:03 +02:00 committed by Ingo Molnar
parent 143cf23df2
commit dbdb22754f

View File

@ -3662,6 +3662,9 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
if (retval)
return retval;
if (attr.sched_policy < 0)
return -EINVAL;
rcu_read_lock();
retval = -ESRCH;
p = find_process_by_pid(pid);