src/java.base/unix/native/libnet/net_util_md.c

@@ -801,22 +801,28 @@
             *len = sizeof(struct sockaddr_in6);
         }
 
 #ifdef __linux__
         /*
-         * On Linux if we are connecting to a link-local address
-         * we need to specify the interface in the scope_id (2.4 kernel only)
+         * On Linux if we are connecting to a
+         *
+         *   - link-local address
+         *   - multicast interface-local or link-local address
+         *
+         * we need to specify the interface in the scope_id.
          *
          * If the scope was cached then we use the cached value. If not cached but
          * specified in the Inet6Address we use that, but we first check if the
          * address needs to be routed via the loopback interface. In this case,
          * we override the specified value with that of the loopback interface.
          * If no cached value exists and no value was specified by user, then
          * we try to determine a value from the routing table. In all these
          * cases the used value is cached for further use.
          */
-        if (IN6_IS_ADDR_LINKLOCAL(&sa->sa6.sin6_addr)) {
+        if (IN6_IS_ADDR_LINKLOCAL(&sa->sa6.sin6_addr)
+            || IN6_IS_ADDR_MC_NODELOCAL(&sa->sa6.sin6_addr)
+            || IN6_IS_ADDR_MC_LINKLOCAL(&sa->sa6.sin6_addr)) {
             unsigned int cached_scope_id = 0, scope_id = 0;
 
             if (ia6_cachedscopeidID) {
                 cached_scope_id = (int)(*env)->GetIntField(env, iaObj, ia6_cachedscopeidID);
                 /* if cached value exists then use it. Otherwise, check