Input: reduce raciness when input handlers disconnect

There is a race between input handler's release() and disconnect()
methods: when input handler disconnects it wakes up all regular
users and then process to walk user list to wake up async. users.
While disconnect() walks the list release() removes elements of
the same list causing oopses.

While this is not a substibute for proper locking we can reduce
odds of getting an oops if we wake up normal readers after walking
the list.
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

drivers/input/evdev.c

@@ -700,9 +700,9 @@ static void evdev_disconnect(struct input_handle *handle)
 	if (evdev->open) {
 		input_flush_device(handle, NULL);
 		input_close_device(handle);
-		wake_up_interruptible(&evdev->wait);
 		list_for_each_entry(client, &evdev->client_list, node)
 			kill_fasync(&client->fasync, SIGIO, POLL_HUP);
+		wake_up_interruptible(&evdev->wait);
 	} else
 		evdev_free(evdev);
 }

drivers/input/joydev.c

@@ -595,9 +595,9 @@ static void joydev_disconnect(struct input_handle *handle)
 
 	if (joydev->open) {
 		input_close_device(handle);
-		wake_up_interruptible(&joydev->wait);
 		list_for_each_entry(client, &joydev->client_list, node)
 			kill_fasync(&client->fasync, SIGIO, POLL_HUP);
+		wake_up_interruptible(&joydev->wait);
 	} else
 		joydev_free(joydev);
 }

drivers/input/mousedev.c

@@ -767,9 +767,9 @@ static void mousedev_disconnect(struct input_handle *handle)
 
 	if (mousedev->open) {
 		input_close_device(handle);
-		wake_up_interruptible(&mousedev->wait);
 		list_for_each_entry(client, &mousedev->client_list, node)
 			kill_fasync(&client->fasync, SIGIO, POLL_HUP);
+		wake_up_interruptible(&mousedev->wait);
 	} else
 		mousedev_free(mousedev);
 }

drivers/input/tsdev.c

@@ -477,9 +477,9 @@ static void tsdev_disconnect(struct input_handle *handle)
 
 	if (tsdev->open) {
 		input_close_device(handle);
-		wake_up_interruptible(&tsdev->wait);
 		list_for_each_entry(client, &tsdev->client_list, node)
 			kill_fasync(&client->fasync, SIGIO, POLL_HUP);
+		wake_up_interruptible(&tsdev->wait);
 	} else
 		tsdev_free(tsdev);
 }