USB: serial: fix race between probe and open

[linux-flexiantxendom0.git] / drivers / usb / serial / usb-serial.c

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index cc274fd..38d7ebd 100644 (file)
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -1059,6 +1059,12 @@ int usb_serial_probe(struct usb_interface *interface,
                serial->attached = 1;
        }
 
+       /* Avoid race with tty_open and serial_install by setting the
+        * disconnected flag and not clearing it until all ports have been
+        * registered.
+        */
+       serial->disconnected = 1;
+
        if (get_free_serial(serial, num_ports, &minor) == NULL) {
                dev_err(&interface->dev, "No more free serial devices\n");
                goto probe_error;
@@ -1083,6 +1089,8 @@ int usb_serial_probe(struct usb_interface *interface,
                }
        }
 
+       serial->disconnected = 0;
+
        usb_serial_console_init(debug, minor);
 
 exit: