list-subsys: fix NULL dereference when trying to use -o json on older kernels

Signed-off-by: Yair Elharrar <yair@excelero.com>

diff --git a/util/json.c b/util/json.c
index f213fec8ea863523e622279d37beb00c8cc809d7..297841057db043c61411451aa93366888f437552 100644 (file)
--- a/util/json.c
+++ b/util/json.c
@@ -119,7 +119,7 @@ static struct json_value *json_create_value_string(const char *str)
 
        if (value) {
                value->type = JSON_TYPE_STRING;
-               value->string = strdup_escape(str);
+               value->string = strdup_escape(str ? str : "(null)");
                if (!value->string) {
                        free(value);
                        value = NULL;