| Message ID | 20210104145007.28093-1-johan@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 54d0a3ab80f49f19ee916def62fe067596833403 |
| Headers | show |
| Series | USB: serial: iuu_phoenix: fix DMA from stack | expand |
On Mon, Jan 04, 2021 at 03:50:07PM +0100, Johan Hovold wrote: > Stack-allocated buffers cannot be used for DMA (on all architectures) so > allocate the flush command buffer using kmalloc(). > > Fixes: 60a8fc017103 ("USB: add iuu_phoenix driver") > Cc: stable <stable@vger.kernel.org> # 2.6.25 > Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On Mon, Jan 04, 2021 at 03:57:51PM +0100, Greg Kroah-Hartman wrote: > On Mon, Jan 04, 2021 at 03:50:07PM +0100, Johan Hovold wrote: > > Stack-allocated buffers cannot be used for DMA (on all architectures) so > > allocate the flush command buffer using kmalloc(). > > > > Fixes: 60a8fc017103 ("USB: add iuu_phoenix driver") > > Cc: stable <stable@vger.kernel.org> # 2.6.25 > > Signed-off-by: Johan Hovold <johan@kernel.org> > > Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Thanks for reviewing. Now applied. Johan
diff --git a/drivers/usb/serial/iuu_phoenix.c b/drivers/usb/serial/iuu_phoenix.c index f1201d4de297..e8f06b41a503 100644 --- a/drivers/usb/serial/iuu_phoenix.c +++ b/drivers/usb/serial/iuu_phoenix.c @@ -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; }
Stack-allocated buffers cannot be used for DMA (on all architectures) so allocate the flush command buffer using kmalloc(). Fixes: 60a8fc017103 ("USB: add iuu_phoenix driver") Cc: stable <stable@vger.kernel.org> # 2.6.25 Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/usb/serial/iuu_phoenix.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-)