diff --git a/src/core/devices/nm-device-tun.c b/src/core/devices/nm-device-tun.c
index faab86d0a9..b277c378a2 100644
--- a/src/core/devices/nm-device-tun.c
+++ b/src/core/devices/nm-device-tun.c
@@ -242,12 +242,14 @@ create_and_realize(NMDevice              *device,
         g_return_val_if_reached(FALSE);
     }
 
-    owner = _nm_utils_ascii_str_to_int64(nm_setting_tun_get_owner(s_tun), 10, 0, G_MAXINT32, -1);
+    owner =
+        _nm_utils_ascii_str_to_int64(nm_setting_tun_get_owner(s_tun), 10, 0, G_MAXUINT32 - 1, -1);
     if (owner != -1) {
         props.owner_valid = TRUE;
         props.owner       = owner;
     }
-    group = _nm_utils_ascii_str_to_int64(nm_setting_tun_get_group(s_tun), 10, 0, G_MAXINT32, -1);
+    group =
+        _nm_utils_ascii_str_to_int64(nm_setting_tun_get_group(s_tun), 10, 0, G_MAXUINT32 - 1, -1);
     if (group != -1) {
         props.group_valid = TRUE;
         props.group       = group;
@@ -278,7 +280,7 @@ _same_og(const char *str, gboolean og_valid, guint32 og_num)
 {
     gint64 v;
 
-    v = _nm_utils_ascii_str_to_int64(str, 10, 0, G_MAXINT32, -1);
+    v = _nm_utils_ascii_str_to_int64(str, 10, 0, G_MAXUINT32 - 1, -1);
     return (!og_valid && (v == (gint64) -1)) || (og_valid && (((guint32) v) == og_num));
 }
 
diff --git a/src/libnm-core-impl/nm-setting-tun.c b/src/libnm-core-impl/nm-setting-tun.c
index 05460104a4..cac0f10beb 100644
--- a/src/libnm-core-impl/nm-setting-tun.c
+++ b/src/libnm-core-impl/nm-setting-tun.c
@@ -166,7 +166,7 @@ verify(NMSetting *setting, NMConnection *connection, GError **error)
     }
 
     if (priv->owner) {
-        if (_nm_utils_ascii_str_to_int64(priv->owner, 10, 0, G_MAXINT32, -1) == -1) {
+        if (_nm_utils_ascii_str_to_int64(priv->owner, 10, 0, G_MAXUINT32 - 1, -1) == -1) {
             g_set_error(error,
                         NM_CONNECTION_ERROR,
                         NM_CONNECTION_ERROR_INVALID_PROPERTY,
@@ -178,7 +178,7 @@ verify(NMSetting *setting, NMConnection *connection, GError **error)
     }
 
     if (priv->group) {
-        if (_nm_utils_ascii_str_to_int64(priv->group, 10, 0, G_MAXINT32, -1) == -1) {
+        if (_nm_utils_ascii_str_to_int64(priv->group, 10, 0, G_MAXUINT32 - 1, -1) == -1) {
             g_set_error(error,
                         NM_CONNECTION_ERROR,
                         NM_CONNECTION_ERROR_INVALID_PROPERTY,