Enet's lwIP adaptation layer has a pbuf leak that causes packet reception to stop due to descriptor starvation. This issue occurs when lwIP network interface is stressed in high bandwidth usecases.

When the issue occurred, the RX flow FQ ring used by lwIP netif had 0 descriptors enqueued, which effectively prevents further packets from being received.

Once issue has occurred, lwIP netif is not able to receive packets anymore until system is rebooted.