[PATCH v3 net 2/8] net: enetc: keep track of correct Tx BD count in enetc_map_tx_tso_buffs()

Wei Fang
2025-02-24T11:30:05Z

When creating a TSO header, if the skb is VLAN tagged, the extended BD
will be used and the 'count' should be increased by 2 instead of 1.
Otherwise, when an error occurs, less tx_swbd will be freed than the
actual number.

Fixes: fb8629e2cbfc ("net: enetc: add support for software TSO")
Cc: stable@vger.kernel.org
Suggested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Wei Fang <wei.fang@nxp.com>
---
drivers/net/ethernet/freescale/enetc/enetc.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 55ad31a5073e..174db9e2ce81 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -395,14 +395,15 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
return 0;
}

-static void enetc_map_tx_tso_hdr(struct enetc_bdr *tx_ring, struct sk_buff *skb,
- struct enetc_tx_swbd *tx_swbd,
- union enetc_tx_bd *txbd, int *i, int hdr_len,
- int data_len)
+static int enetc_map_tx_tso_hdr(struct enetc_bdr *tx_ring, struct sk_buff *skb,
+ struct enetc_tx_swbd *tx_swbd,
+ union enetc_tx_bd *txbd, int *i, int hdr_len,
+ int data_len)
{
union enetc_tx_bd txbd_tmp;
u8 flags = 0, e_flags = 0;
dma_addr_t addr;
+ int count = 1;

enetc_clear_tx_bd(&txbd_tmp);
addr = tx_ring->tso_headers_dma + *i * TSO_HEADER_SIZE;
@@ -445,7 +446,10 @@ static void enetc_map_tx_tso_hdr(struct enetc_bdr *tx_ring, struct sk_buff *skb,
/* Write the BD */
txbd_tmp.ext.e_flags = e_flags;
*txbd = txbd_tmp;
+ count++;
}
+
+ return count;
}

static int enetc_map_tx_tso_data(struct enetc_bdr *tx_ring, struct sk_buff *skb,
@@ -802,9 +806,9 @@ static int enetc_map_tx_tso_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb

/* compute the csum over the L4 header */
csum = enetc_tso_hdr_csum(&tso, skb, hdr, hdr_len, &pos);
- enetc_map_tx_tso_hdr(tx_ring, skb, tx_swbd, txbd, &i, hdr_len, data_len);
+ count += enetc_map_tx_tso_hdr(tx_ring, skb, tx_swbd, txbd,
+ &i, hdr_len, data_len);
bd_data_num = 0;
- count++;

while (data_len > 0) {
int size;
--
2.34.1