error_t lpc546xxEthSendPacket(NetInterface *interface,
   const NetBuffer *buffer, size_t offset, NetTxAncillary *ancillary)
{
   size_t length;

   //Retrieve the length of the packet
   length = netBufferGetLength(buffer) - offset;

   //Check the frame length
   if(length > LPC546XX_ETH_TX_BUFFER_SIZE)
   {
      //The transmitter can accept another packet
      osSetEvent(&interface->nicTxEvent);
      //Report an error
      return ERROR_INVALID_LENGTH;
   }

   //Make sure the current buffer is available for writing
   if((txDmaDesc[txIndex].tdes3 & ENET_TDES3_OWN) != 0)
   {
      return ERROR_FAILURE;
   }

   //Copy user data to the transmit buffer
   netBufferRead(txBuffer[txIndex], buffer, offset, length);

   //Set the start address of the buffer
   txDmaDesc[txIndex].tdes0 = (uint32_t) txBuffer[txIndex];
   //Write the number of bytes to send
   txDmaDesc[txIndex].tdes2 = ENET_TDES2_IOC | (length & ENET_TDES2_B1L);
   //Give the ownership of the descriptor to the DMA
   txDmaDesc[txIndex].tdes3 = ENET_TDES3_OWN | ENET_TDES3_FD | ENET_TDES3_LD;

   //Clear TBU flag to resume processing
   ENET->DMA_CH[0].DMA_CHX_STAT = ENET_DMA_CH_DMA_CHX_STAT_TBU_MASK;
   //Instruct the DMA to poll the transmit descriptor list
   ENET->DMA_CH[0].DMA_CHX_TXDESC_TAIL_PTR = 0;

   //Increment index and wrap around if necessary
   if(++txIndex >= LPC546XX_ETH_TX_BUFFER_COUNT)
   {
      txIndex = 0;
   }

   //Check whether the next buffer is available for writing
   if((txDmaDesc[txIndex].tdes3 & ENET_TDES3_OWN) == 0)
   {
      //The transmitter can accept another packet
      osSetEvent(&interface->nicTxEvent);
   }

   //Data successfully written
   return NO_ERROR;
}
The product receives input or data, but it does
        not validate or incorrectly validates that the input has the
        properties that are required to process the data safely and
        correctly.