[PATCH 4.9 051/171] net/mlx5: Fix command completion after timeout access invalid structure

[Greg Kroah-Hartman]

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

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

[ Upstream commit 061870800efb4e3d1ad4082a2569363629bdfcfc ]

Completion on timeout should not free the driver command entry structure
as it will need to access it again once real completion event from FW
will occur.

Fixes: 73dd3a4839c1 ('net/mlx5: Avoid using pending command interface slots')
Signed-off-by: Moshe Shemesh <moshe@xxxxxxxxxxxx>
Cc: kernel-team@xxxxxx
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
index 9680c8805178..1d5263c46eee 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
@@ -965,7 +965,7 @@ static int mlx5_cmd_invoke(struct mlx5_core_dev *dev, struct mlx5_cmd_msg *in,
 
 	err = wait_func(dev, ent);
 	if (err == -ETIMEDOUT)
-		goto out_free;
+		goto out;
 
 	ds = ent->ts2 - ent->ts1;
 	op = MLX5_GET(mbox_in, in->first.data, opcode);
@@ -1428,6 +1428,7 @@ void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, u64 vec, bool forced)
 					mlx5_core_err(dev, "Command completion arrived after timeout (entry idx = %d).\n",
 						      ent->idx);
 					free_ent(cmd, ent->idx);
+					free_cmd(ent);
 				}
 				continue;
 			}
@@ -1486,7 +1487,8 @@ void mlx5_cmd_comp_handler(struct mlx5_core_dev *dev, u64 vec, bool forced)
 				free_msg(dev, ent->in);
 
 				err = err ? err : ent->status;
-				free_cmd(ent);
+				if (!forced)
+					free_cmd(ent);
 				callback(err, context);
 			} else {
 				complete(&ent->done);
-- 
2.17.1