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Diffstat (limited to 'kernel/sched/core.c')
-rw-r--r--kernel/sched/core.c55
1 files changed, 39 insertions, 16 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 204d3d28180..0a725167898 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3195,17 +3195,40 @@ __getparam_dl(struct task_struct *p, struct sched_attr *attr)
* We ask for the deadline not being zero, and greater or equal
* than the runtime, as well as the period of being zero or
* greater than deadline. Furthermore, we have to be sure that
- * user parameters are above the internal resolution (1us); we
- * check sched_runtime only since it is always the smaller one.
+ * user parameters are above the internal resolution of 1us (we
+ * check sched_runtime only since it is always the smaller one) and
+ * below 2^63 ns (we have to check both sched_deadline and
+ * sched_period, as the latter can be zero).
*/
static bool
__checkparam_dl(const struct sched_attr *attr)
{
- return attr && attr->sched_deadline != 0 &&
- (attr->sched_period == 0 ||
- (s64)(attr->sched_period - attr->sched_deadline) >= 0) &&
- (s64)(attr->sched_deadline - attr->sched_runtime ) >= 0 &&
- attr->sched_runtime >= (2 << (DL_SCALE - 1));
+ /* deadline != 0 */
+ if (attr->sched_deadline == 0)
+ return false;
+
+ /*
+ * Since we truncate DL_SCALE bits, make sure we're at least
+ * that big.
+ */
+ if (attr->sched_runtime < (1ULL << DL_SCALE))
+ return false;
+
+ /*
+ * Since we use the MSB for wrap-around and sign issues, make
+ * sure it's not set (mind that period can be equal to zero).
+ */
+ if (attr->sched_deadline & (1ULL << 63) ||
+ attr->sched_period & (1ULL << 63))
+ return false;
+
+ /* runtime <= deadline <= period (if period != 0) */
+ if ((attr->sched_period != 0 &&
+ attr->sched_period < attr->sched_deadline) ||
+ attr->sched_deadline < attr->sched_runtime)
+ return false;
+
+ return true;
}
/*
@@ -3658,8 +3681,12 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
if (!uattr || pid < 0 || flags)
return -EINVAL;
- if (sched_copy_attr(uattr, &attr))
- return -EFAULT;
+ retval = sched_copy_attr(uattr, &attr);
+ if (retval)
+ return retval;
+
+ if (attr.sched_policy < 0)
+ return -EINVAL;
rcu_read_lock();
retval = -ESRCH;
@@ -3709,7 +3736,7 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
*/
SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
{
- struct sched_param lp;
+ struct sched_param lp = { .sched_priority = 0 };
struct task_struct *p;
int retval;
@@ -3726,11 +3753,8 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
if (retval)
goto out_unlock;
- if (task_has_dl_policy(p)) {
- retval = -EINVAL;
- goto out_unlock;
- }
- lp.sched_priority = p->rt_priority;
+ if (task_has_rt_policy(p))
+ lp.sched_priority = p->rt_priority;
rcu_read_unlock();
/*
@@ -5052,7 +5076,6 @@ static int sched_cpu_active(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_STARTING:
case CPU_DOWN_FAILED:
set_cpu_active((long)hcpu, true);
return NOTIFY_OK;