[PATCH rdma-next 1/3] RDMA/mlx5: Return an error if copy_to_user fails

[Leon Romanovsky <leon@kernel.org>]

From: Leon Romanovsky <leonro@mellanox.com>

In theoretical event, the ib_copy_to_udata() can fail, so
return -EFAULT error to the user, so he will destroy the QP.

Fixes: 50aec2c3135e ("RDMA/mlx5: Return ECE data after modify QP")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
---
 drivers/infiniband/hw/mlx5/qp.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index bc776542efd3..e8427231cf15 100644
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -4305,12 +4305,8 @@ int mlx5_ib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 	/* resp.response_length is set in ECE supported flows only */
 	if (!err && resp.response_length &&
 	    udata->outlen >= resp.response_length)
-		/*
-		 * We don't check return value of the function below
-		 * on purpose, because it is unclear how to unwind the
-		 * error flow after QP was modified to the new state.
-		 */
-		ib_copy_to_udata(udata, &resp, resp.response_length);
+		/* Return -EFAULT to the user and expect him to destroy QP. */
+		err = ib_copy_to_udata(udata, &resp, resp.response_length);
 
 out:
 	mutex_unlock(&qp->mutex);
-- 
2.26.2