[PATCH net] net/mlx5e: psp, avoid 'accel' NULL pointer dereference

Tariq Toukan
2025-10-15T07:06:10Z

From: Cosmin Ratiu <cratiu@nvidia.com>

The 'accel' parameter of mlx5e_txwqe_build_eseg_csum() and the similar
'state' parameter of mlx5e_accel_tx_ids_len() were NULL when called
from mlx5i_sq_xmit() and were causing kernel panics from that context.

Fix that by passing in a local empty mlx5e_accel_tx_state variable, thus
guaranteeing that 'accel' is never NULL. Also remove an unnecessary
check from mlx5e_tx_wqe_inline_mode().

Fixes: e5a1861a298e ("net/mlx5e: Implement PSP Tx data path")
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
drivers/net/ethernet/mellanox/mlx5/core/en_tx.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
index b7227afcb51d..2702b3885f06 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -256,7 +256,7 @@ mlx5e_tx_wqe_inline_mode(struct mlx5e_txqsq *sq, struct sk_buff *skb,
u8 mode;

#ifdef CONFIG_MLX5_EN_TLS
- if (accel && accel->tls.tls_tisn)
+ if (accel->tls.tls_tisn)
return MLX5_INLINE_MODE_TCP_UDP;
#endif

@@ -982,6 +982,7 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
struct mlx5e_tx_attr attr;
struct mlx5i_tx_wqe *wqe;

+ struct mlx5e_accel_tx_state accel = {};
struct mlx5_wqe_datagram_seg *datagram;
struct mlx5_wqe_ctrl_seg *cseg;
struct mlx5_wqe_eth_seg *eseg;
@@ -992,7 +993,7 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
int num_dma;
u16 pi;

- mlx5e_sq_xmit_prepare(sq, skb, NULL, &attr);
+ mlx5e_sq_xmit_prepare(sq, skb, &accel, &attr);
mlx5i_sq_calc_wqe_attr(skb, &attr, &wqe_attr);

pi = mlx5e_txqsq_get_next_pi(sq, wqe_attr.num_wqebbs);
@@ -1009,7 +1010,7 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,

mlx5i_txwqe_build_datagram(av, dqpn, dqkey, datagram);

- mlx5e_txwqe_build_eseg_csum(sq, skb, NULL, eseg);
+ mlx5e_txwqe_build_eseg_csum(sq, skb, &accel, eseg);

eseg->mss = attr.mss;

base-commit: 7f0fddd817ba6daebea1445ae9fab4b6d2294fa8
--
2.31.1