Executive brief
In the Linux kernel, the following vulnerability has been resolved:
tracing: Don't dereference trace_event_file in deferred trigger free
The enable_event trigger defers trace_event_put_ref() to the trigger free kthread, but the trace_event_file can already be freed when the instance is removed.
Keep the trace_event_call directly in enable_trigger_data so the deferred free does not access the freed trace_event_file.