[PATCH 5.15 143/279] net/mlx5e: kTLS, Fix crash in RX resync flow

From: Greg Kroah-Hartman
Date: Wed Nov 24 2021 - 08:54:34 EST


From: Tariq Toukan <tariqt@xxxxxxxxxx>

[ Upstream commit cc4a9cc03faa6d8db1a6954bb536f2c1e63bdff6 ]

For the TLS RX resync flow, we maintain a list of TLS contexts
that require some attention, to communicate their resync information
to the HW.
Here we fix list corruptions, by protecting the entries against
movements coming from resync_handle_seq_match(), until their resync
handling in napi is fully completed.

Fixes: e9ce991bce5b ("net/mlx5e: kTLS, Add resiliency to RX resync failures")
Signed-off-by: Tariq Toukan <tariqt@xxxxxxxxxx>
Reviewed-by: Maxim Mikityanskiy <maximmi@xxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../mellanox/mlx5/core/en_accel/ktls_rx.c | 23 ++++++++++++++-----
1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_rx.c
index 62abce008c7b8..a2a9f68579dd8 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_rx.c
@@ -55,6 +55,7 @@ struct mlx5e_ktls_offload_context_rx {
DECLARE_BITMAP(flags, MLX5E_NUM_PRIV_RX_FLAGS);

/* resync */
+ spinlock_t lock; /* protects resync fields */
struct mlx5e_ktls_rx_resync_ctx resync;
struct list_head list;
};
@@ -386,14 +387,18 @@ static void resync_handle_seq_match(struct mlx5e_ktls_offload_context_rx *priv_r
struct mlx5e_icosq *sq;
bool trigger_poll;

- memcpy(info->rec_seq, &priv_rx->resync.sw_rcd_sn_be, sizeof(info->rec_seq));
-
sq = &c->async_icosq;
ktls_resync = sq->ktls_resync;
+ trigger_poll = false;

spin_lock_bh(&ktls_resync->lock);
- list_add_tail(&priv_rx->list, &ktls_resync->list);
- trigger_poll = !test_and_set_bit(MLX5E_SQ_STATE_PENDING_TLS_RX_RESYNC, &sq->state);
+ spin_lock_bh(&priv_rx->lock);
+ memcpy(info->rec_seq, &priv_rx->resync.sw_rcd_sn_be, sizeof(info->rec_seq));
+ if (list_empty(&priv_rx->list)) {
+ list_add_tail(&priv_rx->list, &ktls_resync->list);
+ trigger_poll = !test_and_set_bit(MLX5E_SQ_STATE_PENDING_TLS_RX_RESYNC, &sq->state);
+ }
+ spin_unlock_bh(&priv_rx->lock);
spin_unlock_bh(&ktls_resync->lock);

if (!trigger_poll)
@@ -617,6 +622,8 @@ int mlx5e_ktls_add_rx(struct net_device *netdev, struct sock *sk,
if (err)
goto err_create_key;

+ INIT_LIST_HEAD(&priv_rx->list);
+ spin_lock_init(&priv_rx->lock);
priv_rx->crypto_info =
*(struct tls12_crypto_info_aes_gcm_128 *)crypto_info;

@@ -730,10 +737,14 @@ bool mlx5e_ktls_rx_handle_resync_list(struct mlx5e_channel *c, int budget)
priv_rx = list_first_entry(&local_list,
struct mlx5e_ktls_offload_context_rx,
list);
+ spin_lock(&priv_rx->lock);
cseg = post_static_params(sq, priv_rx);
- if (IS_ERR(cseg))
+ if (IS_ERR(cseg)) {
+ spin_unlock(&priv_rx->lock);
break;
- list_del(&priv_rx->list);
+ }
+ list_del_init(&priv_rx->list);
+ spin_unlock(&priv_rx->lock);
db_cseg = cseg;
}
if (db_cseg)
--
2.33.0