diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c
index d27fabae8ddd..6c629ef1bc4e 100644
--- a/drivers/scsi/device_handler/scsi_dh_rdac.c
+++ b/drivers/scsi/device_handler/scsi_dh_rdac.c
@@ -546,6 +546,8 @@ static void send_mode_select(struct work_struct *work)
 	spin_unlock(&ctlr->ms_lock);
 
  retry:
+	memset(cdb, 0, sizeof(cdb));
+
 	data_size = rdac_failover_get(ctlr, &list, cdb);
 
 	RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "