tracing: Fix memory leak in create_filter()

The create_filter() calls create_filter_start() which allocates a
"parse_error" descriptor, but fails to call create_filter_finish() that
frees it.

The op_stack and inverts in predicate_parse() were also not freed.

Found by kmemleak detector.

Cc: stable@vger.kernel.org
Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster")
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/trace_events_filter.c

@@ -570,11 +570,13 @@ predicate_parse(const char *str, int nr_parens, int nr_preds,
 		}
 	}
 
+	kfree(op_stack);
+	kfree(inverts);
 	return prog;
 out_free:
 	kfree(op_stack);
-	kfree(prog_stack);
 	kfree(inverts);
+	kfree(prog_stack);
 	return ERR_PTR(ret);
 }
 
@@ -1718,6 +1720,7 @@ static int create_filter(struct trace_event_call *call,
 	err = process_preds(call, filter_string, *filterp, pe);
 	if (err && set_str)
 		append_filter_err(pe, *filterp);
+	create_filter_finish(pe);
 
 	return err;
 }