diff --git a/fs/proc/base.c b/fs/proc/base.c
index d7fd1ca807d2..58a8dc3fd6c6 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2356,10 +2356,13 @@ static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
 		return -ESRCH;
 
 	if (p != current) {
-		if (!capable(CAP_SYS_NICE)) {
+		rcu_read_lock();
+		if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
+			rcu_read_unlock();
 			count = -EPERM;
 			goto out;
 		}
+		rcu_read_unlock();
 
 		err = security_task_setscheduler(p);
 		if (err) {
@@ -2392,11 +2395,14 @@ static int timerslack_ns_show(struct seq_file *m, void *v)
 		return -ESRCH;
 
 	if (p != current) {
-
-		if (!capable(CAP_SYS_NICE)) {
+		rcu_read_lock();
+		if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
+			rcu_read_unlock();
 			err = -EPERM;
 			goto out;
 		}
+		rcu_read_unlock();
+
 		err = security_task_getscheduler(p);
 		if (err)
 			goto out;