static struct ath_buf* ath_clone_txbuf(struct ath_softc *sc, struct ath_buf *bf)
{
	struct ath_buf *tbf;

	tbf = ath_tx_get_buffer(sc);
	if (WARN_ON(!tbf))
		return NULL;

	ATH_TXBUF_RESET(tbf);

	tbf->bf_mpdu = bf->bf_mpdu;
	tbf->bf_buf_addr = bf->bf_buf_addr;
	memcpy(tbf->bf_desc, bf->bf_desc, sc->sc_ah->caps.tx_desc_len);
	tbf->bf_state = bf->bf_state;
	tbf->bf_state.stale = false;

	return tbf;
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.