USB: serial: iuu_phoenix: fix DMA from stack

Stack-allocated buffers cannot be used for DMA (on all architectures) so
allocate the flush command buffer using kmalloc().

Fixes: 60a8fc0171 ("USB: add iuu_phoenix driver")
Cc: stable <stable@vger.kernel.org>     # 2.6.25
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
This commit is contained in:
Johan Hovold 2021-01-04 15:50:07 +01:00
parent 0e2d6795e8
commit 54d0a3ab80
1 changed files with 15 additions and 5 deletions

View File

@ -532,23 +532,29 @@ static int iuu_uart_flush(struct usb_serial_port *port)
struct device *dev = &port->dev;
int i;
int status;
u8 rxcmd = IUU_UART_RX;
u8 *rxcmd;
struct iuu_private *priv = usb_get_serial_port_data(port);
if (iuu_led(port, 0xF000, 0, 0, 0xFF) < 0)
return -EIO;
rxcmd = kmalloc(1, GFP_KERNEL);
if (!rxcmd)
return -ENOMEM;
rxcmd[0] = IUU_UART_RX;
for (i = 0; i < 2; i++) {
status = bulk_immediate(port, &rxcmd, 1);
status = bulk_immediate(port, rxcmd, 1);
if (status != IUU_OPERATION_OK) {
dev_dbg(dev, "%s - uart_flush_write error\n", __func__);
return status;
goto out_free;
}
status = read_immediate(port, &priv->len, 1);
if (status != IUU_OPERATION_OK) {
dev_dbg(dev, "%s - uart_flush_read error\n", __func__);
return status;
goto out_free;
}
if (priv->len > 0) {
@ -556,12 +562,16 @@ static int iuu_uart_flush(struct usb_serial_port *port)
status = read_immediate(port, priv->buf, priv->len);
if (status != IUU_OPERATION_OK) {
dev_dbg(dev, "%s - uart_flush_read error\n", __func__);
return status;
goto out_free;
}
}
}
dev_dbg(dev, "%s - uart_flush_read OK!\n", __func__);
iuu_led(port, 0, 0xF000, 0, 0xFF);
out_free:
kfree(rxcmd);
return status;
}