HID: magicmouse: fix crash when disconnecting Magic Trackpad 2

When the Apple Magic Trackpad 2 is connected over USB it registers four
hid_device report descriptors, however, the driver only handles the one
with type HID_TYPE_USBMOUSE and ignores the other three, thus, no driver
data is attached to them.

When the device is disconnected, the remove callback is called for the
four hid_device report descriptors, crashing when the driver data is
NULL.

Check that the driver data is not NULL before using it in the remove
callback.

Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-magicmouse.c b/drivers/hid/hid-magicmouse.c
index 2bb473d..097870e 100644 (file)
--- a/drivers/hid/hid-magicmouse.c
+++ b/drivers/hid/hid-magicmouse.c
@@ -779,7 +779,10 @@ err_stop_hw:
 static void magicmouse_remove(struct hid_device *hdev)
 {
        struct magicmouse_sc *msc = hid_get_drvdata(hdev);
-       cancel_delayed_work_sync(&msc->work);
+
+       if (msc)
+               cancel_delayed_work_sync(&msc->work);
+
        hid_hw_stop(hdev);
 }