diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 93fb6ed..a4fb703 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -765,7 +765,7 @@
 			goto out;
 	}
 
-	rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
+	rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 	memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 	if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
 		memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);