tracing/kprobe: Release kprobe print_fmt properly

We don't release tk->tp.call.print_fmt when destroying
local uprobe. Also there's missing print_fmt kfree in
create_local_trace_kprobe error path.

Link: http://lkml.kernel.org/r/20180709141906.2390-1-jolsa@kernel.org

Cc: stable@vger.kernel.org
Fixes: e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU")
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

kernel/trace/trace_kprobe.c

@@ -1480,8 +1480,10 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
 	}
 
 	ret = __register_trace_kprobe(tk);
-	if (ret < 0)
+	if (ret < 0) {
+		kfree(tk->tp.call.print_fmt);
 		goto error;
+	}
 
 	return &tk->tp.call;
 error:
@@ -1501,6 +1503,8 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call)
 	}
 
 	__unregister_trace_kprobe(tk);
+
+	kfree(tk->tp.call.print_fmt);
 	free_trace_kprobe(tk);
 }
 #endif /* CONFIG_PERF_EVENTS */