Re: [PATCH v2 06/13] net/txgbe: check length of Tx packets

[Ferruh Yigit <ferruh.yigit@amd.com>]

On 10/28/2024 2:31 AM, Jiawen Wu wrote:
> Add checking of the Tx packet length to avoid TDM fatal error as far as
> possible. Set the pkt_len=1518 for invalid packet in simple Tx code path,
> and drop it directly in featured Tx code path.
> 
> Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
> ---
>  drivers/net/txgbe/txgbe_rxtx.c          | 33 +++++++++++++++++++++++++
>  drivers/net/txgbe/txgbe_rxtx_vec_neon.c | 10 +++++---
>  drivers/net/txgbe/txgbe_rxtx_vec_sse.c  | 11 ++++++---
>  3 files changed, 48 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/txgbe/txgbe_rxtx.c b/drivers/net/txgbe/txgbe_rxtx.c
> index 2d2b437643..06acbd0881 100644
> --- a/drivers/net/txgbe/txgbe_rxtx.c
> +++ b/drivers/net/txgbe/txgbe_rxtx.c
> @@ -160,6 +160,8 @@ tx4(volatile struct txgbe_tx_desc *txdp, struct rte_mbuf **pkts)
>  	for (i = 0; i < 4; ++i, ++txdp, ++pkts) {
>  		buf_dma_addr = rte_mbuf_data_iova(*pkts);
>  		pkt_len = (*pkts)->data_len;
> +		if (pkt_len < RTE_ETHER_HDR_LEN)
> +			pkt_len = TXGBE_FRAME_SIZE_DFT;
>  
>  		/* write data to descriptor */
>  		txdp->qw0 = rte_cpu_to_le_64(buf_dma_addr);
> @@ -180,6 +182,8 @@ tx1(volatile struct txgbe_tx_desc *txdp, struct rte_mbuf **pkts)
>  
>  	buf_dma_addr = rte_mbuf_data_iova(*pkts);
>  	pkt_len = (*pkts)->data_len;
> +	if (pkt_len < RTE_ETHER_HDR_LEN)
> +		pkt_len = TXGBE_FRAME_SIZE_DFT;
>  
>  	/* write data to descriptor */
>  	txdp->qw0 = cpu_to_le64(buf_dma_addr);
> @@ -813,6 +817,30 @@ txgbe_parse_tun_ptid(struct rte_mbuf *tx_pkt, uint8_t tun_len)
>  	return ptid;
>  }
>  
> +static inline bool
> +txgbe_check_pkt_err(struct rte_mbuf *tx_pkt)
> +{
> +	uint32_t total_len = 0, nb_seg = 0;
> +	struct rte_mbuf *mseg;
> +
> +	mseg = tx_pkt;
> +	do {
> +		if (mseg->data_len == 0)
> +			return true;
> +		total_len += mseg->data_len;
> +		nb_seg++;
> +		mseg = mseg->next;
> +	} while (mseg != NULL);
> +
> +	if (tx_pkt->pkt_len != total_len || tx_pkt->pkt_len == 0)
> +		return true;
> +
> +	if (tx_pkt->nb_segs != nb_seg || tx_pkt->nb_segs > 64)
> +		return true;
> +
> +	return false;
> +}
> +
>

Hi Jiawen,

Above are generic checks, we may add this function to ethdev driver
header (ethdev_driver.h) so that any PMD can use it, what do you think?