charger-manager: Ensure event is not used as format string

commit 3594f4c0 upstream.

The exposed interface for cm_notify_event() could result in the event msg
string being parsed as a format string. Make sure it is only used as a
literal string.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/power/charger-manager.c

@@ -450,7 +450,7 @@ static void uevent_notify(struct charger_manager *cm, const char *event)
 	strncpy(env_str, event, UEVENT_BUF_SIZE);
 	kobject_uevent(&cm->dev->kobj, KOBJ_CHANGE);
 
-	dev_info(cm->dev, event);
+	dev_info(cm->dev, "%s", event);
 }
 
 /**