diff --git a/fs/proc/base.c b/fs/proc/base.c
index 9b423fec9732..51507065263b 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3097,10 +3097,14 @@ out_no_task:
  * In the case of a seek we start with the leader and walk nr
  * threads past it.
  */
-static struct task_struct *first_tid(struct pid *pid, int tid,
-					int nr, struct pid_namespace *ns)
+static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
+					struct pid_namespace *ns)
 {
 	struct task_struct *pos, *task;
+	unsigned long nr = f_pos;
+
+	if (nr != f_pos)	/* 32bit overflow? */
+		return NULL;
 
 	rcu_read_lock();
 	task = pid_task(pid, PIDTYPE_PID);
@@ -3108,14 +3112,14 @@ static struct task_struct *first_tid(struct pid *pid, int tid,
 		goto fail;
 
 	/* Attempt to start with the tid of a thread */
-	if (tid && (nr > 0)) {
+	if (tid && nr) {
 		pos = find_task_by_pid_ns(tid, ns);
 		if (pos && same_thread_group(pos, task))
 			goto found;
 	}
 
 	/* If nr exceeds the number of threads there is nothing todo */
-	if (nr && nr >= get_nr_threads(task))
+	if (nr >= get_nr_threads(task))
 		goto fail;
 
 	/* If we haven't found our starting place yet start
@@ -3123,7 +3127,7 @@ static struct task_struct *first_tid(struct pid *pid, int tid,
 	 */
 	pos = task = task->group_leader;
 	do {
-		if (nr-- <= 0)
+		if (!nr--)
 			goto found;
 	} while_each_thread(task, pos);
 fail: