diff --git a/udev_enumerate.c b/udev_enumerate.c
index 8aac73d..c553269 100644
--- a/udev_enumerate.c
+++ b/udev_enumerate.c
@@ -193,20 +193,17 @@ static int filter_property(struct udev_enumerate *udev_enumerate, struct udev_de
 
 static int filter_sysattr(struct udev_enumerate *udev_enumerate, struct udev_device *udev_device)
 {
+    const char *sysattr, *value, *value2;
     struct udev_list_entry *list_entry;
-    const char *sysattr, *value;
 
     list_entry = udev_list_entry_get_next(&udev_enumerate->sysattr_nomatch);
 
     while (list_entry) {
         sysattr = udev_list_entry_get_name(list_entry);
+        value2 = udev_list_entry_get_value(list_entry);
         value = udev_device_get_sysattr_value(udev_device, sysattr);
 
-        if (!value) {
-            return 1;
-        }
-
-        if (fnmatch(udev_list_entry_get_value(list_entry), value, 0) == 0) {
+        if (value && value2 && fnmatch(value2, value, 0) == 0) {
             return 0;
         }
 
@@ -218,13 +215,10 @@ static int filter_sysattr(struct udev_enumerate *udev_enumerate, struct udev_dev
     if (list_entry) {
         while (list_entry) {
             sysattr = udev_list_entry_get_name(list_entry);
+            value2 = udev_list_entry_get_value(list_entry);
             value = udev_device_get_sysattr_value(udev_device, sysattr);
 
-            if (!value) {
-                return 0;
-            }
-
-            if (fnmatch(udev_list_entry_get_value(list_entry), value, 0) == 0) {
+            if (value && value2 && fnmatch(value2, value, 0) == 0) {
                 return 1;
             }