platform/x86: wmi: fix potential null pointer dereference

In the function wmi_dev_match() the variable id is dereferenced without first performing a NULL check. The variable can for example be NULL if a WMI driver is registered without specifying the id_table field in struct wmi_driver. Add a NULL check and return that the driver can't handle the device if the variable is NULL. Fixes: 844af95 ("platform/x86: wmi: Turn WMI into a bus driver") Signed-off-by: Mattias Jacobsson <[email protected]> Signed-off-by: Darren Hart (VMware) <[email protected]>
crow-misia · Feb 23, 2019 · c355ec6 · c355ec6
1 parent fd47a36
commit c355ec6
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
@@ -768,6 +768,9 @@ static int wmi_dev_match(struct device *dev, struct device_driver *driver)
 	struct wmi_block *wblock = dev_to_wblock(dev);
 	const struct wmi_device_id *id = wmi_driver->id_table;
 
+	if (id == NULL)
+		return 0;
+
 	while (id->guid_string) {
 		uuid_le driver_guid;