On 13-Sep-24 17:37, Dan Carpenter wrote:
Hello Yevgeny Kliteynik,
Commit 2ca62599aa0b ("net/mlx5: HWS, added send engine and context
handling") from Jun 20, 2024 (linux-next), leads to the following
Smatch static checker warning:
drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_send.c:739 hws_send_ring_open_sq() warn: 'sq->dep_wqe' double freed
drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_send.c:739 hws_send_ring_open_sq() warn: 'sq->wq_ctrl.buf.frags' double freed
drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_send.c:739 hws_send_ring_open_sq() warn: 'sq->wr_priv' double freed
...
725
726 err = hws_send_ring_alloc_sq(ctx->mdev, numa_node, queue, sq, sqc_data);
727 if (err)
728 goto err_free_sqc;
729
730 err = hws_send_ring_create_sq_rdy(ctx->mdev, ctx->pd_num, sqc_data,
731 queue, sq, cq);
732 if (err)
733 goto err_free_sq;
hws_send_ring_create_sq_rdy() calls hws_send_ring_close_sq() on error.
I would say that it's the free in hws_send_ring_create_sq_rdy() which
should be modified.
Exactly - it should call the mlx5_core destroy function, but instead it
calls the HWS function. Will have this fixed shortly.
Thanks Dan!
-- YK
There isn't an official style guideline for error
handling so do whatever works for you. But I've written a guide to how
people often do it:
https://staticthinking.wordpress.com/2022/04/28/free-the-last-thing-style/
734
735 kvfree(sqc_data);
736
737 return 0;
738 err_free_sq:
--> 739 hws_send_ring_free_sq(sq);
It results in a double free.
740 err_free_sqc:
741 kvfree(sqc_data);
742 return err;
743 }
regards,
dan carpenter
