USB: usb_serial_resume bug fix

Avoid potential null pointer dereference.

Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 426afaa..497e29a 100644 (file)
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -1123,7 +1123,9 @@ int usb_serial_resume(struct usb_interface *intf)
 {
        struct usb_serial *serial = usb_get_intfdata(intf);
 
-       return serial->type->resume(serial);
+       if (serial->type->resume)
+               return serial->type->resume(serial);
+       return 0;
 }
 EXPORT_SYMBOL(usb_serial_resume);