tracing/eprobe: Fix to release eprobe when failed to add dyn_event

Fix eprobe event to unregister event call and release eprobe when it fails
to add dynamic event correctly.

Link: https://lore.kernel.org/all/173289886698.73724.1959899350183686006.stgit@devnote2/

Fixes: 7491e2c ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>

Author: mhiramat

kernel/trace/trace_eprobe.c

@@ -963,6 +963,11 @@ static int __trace_eprobe_create(int argc, const char *argv[])
 		goto error;
 	}
 	ret = dyn_event_add(&ep->devent, &ep->tp.event->call);
+	if (ret < 0) {
+		trace_probe_unregister_event_call(&ep->tp);
+		mutex_unlock(&event_mutex);
+		goto error;
+	}
 	mutex_unlock(&event_mutex);
 	return ret;
 parse_error: