diff --git a/sound/usb/stream.c b/sound/usb/stream.c
index 47cfaf29fdd7..bb919f1d4043 100644
--- a/sound/usb/stream.c
+++ b/sound/usb/stream.c
@@ -350,7 +350,7 @@ snd_pcm_chmap_elem *convert_chmap_v3(struct uac3_cluster_header_descriptor
 		u16 cs_len;
 		u8 cs_type;
 
-		if (len < sizeof(*p))
+		if (len < sizeof(*cs_desc))
 			break;
 		cs_len = le16_to_cpu(cs_desc->wLength);
 		if (len < cs_len)