[PATCH 4.19 28/42] net/mlx5: IPSec, Fix the SA context hash key

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Raed Salem <raeds@mellanox.com>

[ Upstream commit f2b18732ee9863ac036759baf616ffa03c252ed5 ]

The commit "net/mlx5: Refactor accel IPSec code" introduced a
bug where asynchronous short time change in hash key value
by create/release SA context might happen during an asynchronous
hash resize operation this could cause a subsequent remove SA
context operation to fail as the key value used during resize is
not the same key value used when remove SA context operation is
invoked.

This commit fixes the bug by defining the SA context hash key
such that it includes only fields that never change during the
lifetime of the SA context object.

Fixes: d6c4f0298cec ("net/mlx5: Refactor accel IPSec code")
Signed-off-by: Raed Salem <raeds@mellanox.com>
Reviewed-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/fpga/ipsec.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/fpga/ipsec.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fpga/ipsec.c
@@ -83,8 +83,14 @@ struct mlx5_fpga_ipsec_rule {
 };
 
 static const struct rhashtable_params rhash_sa = {
-	.key_len = FIELD_SIZEOF(struct mlx5_fpga_ipsec_sa_ctx, hw_sa),
-	.key_offset = offsetof(struct mlx5_fpga_ipsec_sa_ctx, hw_sa),
+	/* Keep out "cmd" field from the key as it's
+	 * value is not constant during the lifetime
+	 * of the key object.
+	 */
+	.key_len = FIELD_SIZEOF(struct mlx5_fpga_ipsec_sa_ctx, hw_sa) -
+		   FIELD_SIZEOF(struct mlx5_ifc_fpga_ipsec_sa_v1, cmd),
+	.key_offset = offsetof(struct mlx5_fpga_ipsec_sa_ctx, hw_sa) +
+		      FIELD_SIZEOF(struct mlx5_ifc_fpga_ipsec_sa_v1, cmd),
 	.head_offset = offsetof(struct mlx5_fpga_ipsec_sa_ctx, hash),
 	.automatic_shrinking = true,
 	.min_size = 1,