perf c2c: Fix memory leak in build_cl_output()

There is a memory leak problem in the failure paths of
build_cl_output(), so fix it.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Feilong Lin <linfeilong@huawei.com>
Cc: Hu Shiyuan <hushiyuan@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/4d3c0178-5482-c313-98e1-f82090d2d456@huawei.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-c2c.c

@@ -2635,6 +2635,7 @@ static int build_cl_output(char *cl_sort, bool no_source)
 	bool add_sym   = false;
 	bool add_dso   = false;
 	bool add_src   = false;
+	int ret = 0;
 
 	if (!buf)
 		return -ENOMEM;
@@ -2653,7 +2654,8 @@ static int build_cl_output(char *cl_sort, bool no_source)
 			add_dso = true;
 		} else if (strcmp(tok, "offset")) {
 			pr_err("unrecognized sort token: %s\n", tok);
-			return -EINVAL;
+			ret = -EINVAL;
+			goto err;
 		}
 	}
 
@@ -2676,13 +2678,15 @@ static int build_cl_output(char *cl_sort, bool no_source)
 		add_sym ? "symbol," : "",
 		add_dso ? "dso," : "",
 		add_src ? "cl_srcline," : "",
-		"node") < 0)
-		return -ENOMEM;
+		"node") < 0) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
 	c2c.show_src = add_src;
-
+err:
 	free(buf);
-	return 0;
+	return ret;
 }
 
 static int setup_coalesce(const char *coalesce, bool no_source)