On Wed, Feb 19, 2025 at 01:42:47PM +0800, Wei Fang wrote:
> There is an off-by-one issue for the err_chained_bd path, it will free
> one more tx_swbd than expected. But there is no such issue for the
> err_map_data path. To fix this off-by-one issue and make the two error
> handling consistent, the loop condition of error handling is modified
> and the 'count++' operation is moved before enetc_map_tx_tso_data().
>
> Fixes: fb8629e2cbfc ("net: enetc: add support for software TSO")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Wei Fang <wei.fang@xxxxxxx>
> ---
> drivers/net/ethernet/freescale/enetc/enetc.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
> index 9a24d1176479..fe3967268a19 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc.c
> +++ b/drivers/net/ethernet/freescale/enetc/enetc.c
> @@ -832,6 +832,7 @@ static int enetc_map_tx_tso_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb
> txbd = ENETC_TXBD(*tx_ring, i);
> tx_swbd = &tx_ring->tx_swbd[i];
> prefetchw(txbd);
> + count++;
>
> /* Compute the checksum over this segment of data and
> * add it to the csum already computed (over the L4
> @@ -848,7 +849,6 @@ static int enetc_map_tx_tso_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb
> goto err_map_data;
>
> data_len -= size;
> - count++;
> bd_data_num++;
> tso_build_data(skb, &tso, size);
>
> @@ -874,13 +874,13 @@ static int enetc_map_tx_tso_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb
> dev_err(tx_ring->dev, "DMA map error");
>
> err_chained_bd:
> - do {
> + while (count--) {
> tx_swbd = &tx_ring->tx_swbd[i];
> enetc_free_tx_frame(tx_ring, tx_swbd);
> if (i == 0)
> i = tx_ring->bd_count;
> i--;
> - } while (count--);
> + }
>
> return 0;
> }
Thanks for fixing it.
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@xxxxxxxxxxxxxxx>
> --
> 2.34.1
>
