diff --git a/src/libsystemd/sd-device/device-enumerator.c b/src/libsystemd/sd-device/device-enumerator.c
index 3692d46e061..7fd77e94800 100644
--- a/src/libsystemd/sd-device/device-enumerator.c
+++ b/src/libsystemd/sd-device/device-enumerator.c
@@ -137,7 +137,6 @@ _public_ int sd_device_enumerator_add_match_sysattr(sd_device_enumerator *enumer
 
         assert_return(enumerator, -EINVAL);
         assert_return(_sysattr, -EINVAL);
-        assert_return(_value, -EINVAL);
 
         if (match)
                 hashmap = &enumerator->match_sysattr;
@@ -152,9 +151,11 @@ _public_ int sd_device_enumerator_add_match_sysattr(sd_device_enumerator *enumer
         if (!sysattr)
                 return -ENOMEM;
 
-        value = strdup(_value);
-        if (!value)
-                return -ENOMEM;
+        if (_value) {
+                value = strdup(_value);
+                if (!value)
+                        return -ENOMEM;
+        }
 
         r = hashmap_put(*hashmap, sysattr, value);
         if (r < 0)
@@ -174,7 +175,6 @@ _public_ int sd_device_enumerator_add_match_property(sd_device_enumerator *enume
 
         assert_return(enumerator, -EINVAL);
         assert_return(_property, -EINVAL);
-        assert_return(_value, -EINVAL);
 
         r = hashmap_ensure_allocated(&enumerator->match_property, NULL);
         if (r < 0)
@@ -184,9 +184,11 @@ _public_ int sd_device_enumerator_add_match_property(sd_device_enumerator *enume
         if (!property)
                 return -ENOMEM;
 
-        value = strdup(_value);
-        if (!value)
-                return -ENOMEM;
+        if (_value) {
+                value = strdup(_value);
+                if (!value)
+                        return -ENOMEM;
+        }
 
         r = hashmap_put(enumerator->match_property, property, value);
         if (r < 0)
diff --git a/src/libudev/libudev-enumerate.c b/src/libudev/libudev-enumerate.c
index 255fbe808d9..df088946df1 100644
--- a/src/libudev/libudev-enumerate.c
+++ b/src/libudev/libudev-enumerate.c
@@ -196,6 +196,9 @@ _public_ struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enume
 _public_ int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem) {
         assert_return(udev_enumerate, -EINVAL);
 
+        if (!subsystem)
+                return 0;
+
         return sd_device_enumerator_add_match_subsystem(udev_enumerate->enumerator, subsystem, true);
 }
 
@@ -211,6 +214,9 @@ _public_ int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enum
 _public_ int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem) {
         assert_return(udev_enumerate, -EINVAL);
 
+        if (!subsystem)
+                return 0;
+
         return sd_device_enumerator_add_match_subsystem(udev_enumerate->enumerator, subsystem, false);
 }
 
@@ -227,6 +233,9 @@ _public_ int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_en
 _public_ int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value) {
         assert_return(udev_enumerate, -EINVAL);
 
+        if (!sysattr)
+                return 0;
+
         return sd_device_enumerator_add_match_sysattr(udev_enumerate->enumerator, sysattr, value, true);
 }
 
@@ -243,6 +252,9 @@ _public_ int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumer
 _public_ int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value) {
         assert_return(udev_enumerate, -EINVAL);
 
+        if (!sysattr)
+                return 0;
+
         return sd_device_enumerator_add_match_sysattr(udev_enumerate->enumerator, sysattr, value, false);
 }
 
@@ -259,6 +271,9 @@ _public_ int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enum
 _public_ int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value) {
         assert_return(udev_enumerate, -EINVAL);
 
+        if (!property)
+                return 0;
+
         return sd_device_enumerator_add_match_property(udev_enumerate->enumerator, property, value);
 }
 
@@ -274,6 +289,9 @@ _public_ int udev_enumerate_add_match_property(struct udev_enumerate *udev_enume
 _public_ int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumerate, const char *tag) {
         assert_return(udev_enumerate, -EINVAL);
 
+        if (!tag)
+                return 0;
+
         return sd_device_enumerator_add_match_tag(udev_enumerate->enumerator, tag);
 }
 
@@ -335,6 +353,9 @@ _public_ int udev_enumerate_add_match_is_initialized(struct udev_enumerate *udev
 _public_ int udev_enumerate_add_match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname) {
         assert_return(udev_enumerate, -EINVAL);
 
+        if (!sysname)
+                return 0;
+
         return sd_device_enumerator_add_match_sysname(udev_enumerate->enumerator, sysname);
 }