diff --git a/src/shared/ethtool-util.c b/src/shared/ethtool-util.c
index 0cde87f5ac..57bffe00be 100644
--- a/src/shared/ethtool-util.c
+++ b/src/shared/ethtool-util.c
@@ -209,7 +209,7 @@ int ethtool_get_link_info(int *ethtool_fd, const char *ifname,
 
                 speed = ethtool_cmd_speed(&ecmd);
                 *ret_speed = speed == (uint32_t) SPEED_UNKNOWN ?
-                        SIZE_MAX : (size_t) speed * 1000 * 1000;
+                        UINT64_MAX : (uint64_t) speed * 1000 * 1000;
         }
 
         if (ret_duplex)
diff --git a/src/shared/format-table.c b/src/shared/format-table.c
index f12ad2d038..87ef5c3f00 100644
--- a/src/shared/format-table.c
+++ b/src/shared/format-table.c
@@ -2269,7 +2269,7 @@ static int table_data_to_json(TableData *d, JsonVariant **ret) {
 
         case TABLE_SIZE:
         case TABLE_BPS:
-                if (d->size == (size_t) -1)
+                if (d->size == (uint64_t) -1)
                         return json_variant_new_null(ret);
 
                 return json_variant_new_unsigned(ret, d->size);