perf data: Fix error return code in perf_data__create_dir()

Although 'ret' has been initialized to -1, but it will be reassigned by
the "ret = open(...)" statement in the for loop. So that, the value of
'ret' is unknown when asprintf() failed.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.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/20210415083417.3740-1-thunder.leizhen@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/data.c

@@ -35,7 +35,7 @@ void perf_data__close_dir(struct perf_data *data)
 int perf_data__create_dir(struct perf_data *data, int nr)
 {
 	struct perf_data_file *files = NULL;
-	int i, ret = -1;
+	int i, ret;
 
 	if (WARN_ON(!data->is_dir))
 		return -EINVAL;
@@ -51,7 +51,8 @@ int perf_data__create_dir(struct perf_data *data, int nr)
 	for (i = 0; i < nr; i++) {
 		struct perf_data_file *file = &files[i];
 
-		if (asprintf(&file->path, "%s/data.%d", data->path, i) < 0)
+		ret = asprintf(&file->path, "%s/data.%d", data->path, i);
+		if (ret < 0)
 			goto out_err;
 
 		ret = open(file->path, O_RDWR|O_CREAT|O_TRUNC, S_IRUSR|S_IWUSR);