trace_kprobes: Fix memory leak

tp->nr_args is not set before we "goto error",
it causes memory leak for free_trace_probe() use tp->nr_args
to free memory of args.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0CEB95.2060107@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/trace/trace_kprobe.c

@@ -704,10 +704,12 @@ static int create_trace_probe(int argc, char **argv)
 		ret = parse_probe_arg(arg, &tp->args[i].fetch, is_return);
 		if (ret) {
 			pr_info("Parse error at argument%d. (%d)\n", i, ret);
+			kfree(tp->args[i].name);
 			goto error;
 		}
+
+		tp->nr_args++;
 	}
-	tp->nr_args = i;
 
 	ret = register_trace_probe(tp);
 	if (ret)