USB: mos7840: fix tiocmget error handling
commit a91ccd26e75235d86248d018fe3779732bcafd8d upstream.
Make sure to return errors from tiocmget rather than rely on
uninitialised stack data.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index c854235..91293b6 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -1664,7 +1664,11 @@
return -ENODEV;
status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
+ if (status != 1)
+ return -EIO;
status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
+ if (status != 1)
+ return -EIO;
result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
| ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
| ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)