Make sure to detect short transfers when reading a device register. The modem-status handling had sufficient error checks in place, but move handling of short transfers into the register accessor function itself for consistency.
Signed-off-by: Johan Hovold <[email protected]> --- drivers/usb/serial/mos7840.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c index ea27fb23967a..155006acf918 100644 --- a/drivers/usb/serial/mos7840.c +++ b/drivers/usb/serial/mos7840.c @@ -284,9 +284,15 @@ static int mos7840_get_reg_sync(struct usb_serial_port *port, __u16 reg, ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ, MCS_RD_RTYPE, 0, reg, buf, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT); + if (ret < VENDOR_READ_LENGTH) { + if (ret >= 0) + ret = -EIO; + goto out; + } + *val = buf[0]; dev_dbg(&port->dev, "%s offset is %x, return val %x\n", __func__, reg, *val); - +out: kfree(buf); return ret; } @@ -352,8 +358,13 @@ static int mos7840_get_uart_reg(struct usb_serial_port *port, __u16 reg, ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), MCS_RDREQ, MCS_RD_RTYPE, Wval, reg, buf, VENDOR_READ_LENGTH, MOS_WDR_TIMEOUT); + if (ret < VENDOR_READ_LENGTH) { + if (ret >= 0) + ret = -EIO; + goto out; + } *val = buf[0]; - +out: kfree(buf); return ret; } @@ -1479,10 +1490,10 @@ static int mos7840_tiocmget(struct tty_struct *tty) return -ENODEV; status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr); - if (status != 1) + if (status < 0) return -EIO; status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr); - if (status != 1) + if (status < 0) return -EIO; result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0) | ((mcr & MCR_RTS) ? TIOCM_RTS : 0) -- 2.10.2 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
