diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c index e508939daea3..21d01a491405 100644 --- a/drivers/tty/serial/8250/8250_dma.c +++ b/drivers/tty/serial/8250/8250_dma.c @@ -80,6 +80,10 @@ int serial8250_tx_dma(struct uart_8250_port *p) return 0; dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); + if (dma->tx_size < p->port.fifosize) { + ret = -EINVAL; + goto err; + } desc = dmaengine_prep_slave_single(dma->txchan, dma->tx_addr + xmit->tail,