diff --git a/sound/firewire/tascam/tascam-hwdep.c b/sound/firewire/tascam/tascam-hwdep.c
index 74eed9505665..9c3f68d8daef 100644
--- a/sound/firewire/tascam/tascam-hwdep.c
+++ b/sound/firewire/tascam/tascam-hwdep.c
@@ -73,6 +73,7 @@ static long tscm_hwdep_read_queue(struct snd_tscm *tscm, char __user *buf,
 			length = rounddown(remained, sizeof(*entries));
 		if (length == 0)
 			break;
+		tail_pos = head_pos + length / sizeof(*entries);
 
 		spin_unlock_irq(&tscm->lock);
 		if (copy_to_user(pos, &entries[head_pos], length))