2023-01-10 05:22:07

by Dan Carpenter

[permalink] [raw]
Subject: drivers/net/ethernet/mellanox/mlx5/core/en/params.c:481 mlx5e_mpwrq_validate_xsk() error: we previously assumed 'xsk' could be null (see line 478)

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 1fe4fd6f5cad346e598593af36caeadc4f5d4fa9
commit: 6470d2e7e8ed8e9dd560d8dc3e09d1100a17ee26 net/mlx5e: xsk: Use KSM for unaligned XSK
config: i386-randconfig-m021-20230102
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Reported-by: Dan Carpenter <[email protected]>

New smatch warnings:
drivers/net/ethernet/mellanox/mlx5/core/en/params.c:481 mlx5e_mpwrq_validate_xsk() error: we previously assumed 'xsk' could be null (see line 478)

Old smatch warnings:
drivers/net/ethernet/mellanox/mlx5/core/en/params.c:314 mlx5e_mpwqe_get_log_num_strides() warn: signedness bug returning '(-255)'

vim +/xsk +481 drivers/net/ethernet/mellanox/mlx5/core/en/params.c

44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 474 int mlx5e_mpwrq_validate_xsk(struct mlx5_core_dev *mdev, struct mlx5e_params *params,
44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 475 struct mlx5e_xsk_param *xsk)
44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 476 {
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 477 u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
6470d2e7e8ed8e Maxim Mikityanskiy 2022-09-29 @478 bool unaligned = xsk ? xsk->unaligned : false;
^^^
Assumes xsk can be NULL

e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 479 u16 max_mtu_pkts;
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 480
6470d2e7e8ed8e Maxim Mikityanskiy 2022-09-29 @481 if (!mlx5e_check_fragmented_striding_rq_cap(mdev, page_shift, xsk->unaligned))
^^^^^
Unchecked dereference

44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 482 return -EOPNOTSUPP;
44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 483
44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 484 if (!mlx5e_rx_mpwqe_is_linear_skb(mdev, params, xsk))
44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 485 return -EINVAL;
44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 486
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 487 /* Current RQ length is too big for the given frame size, the
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 488 * needed number of WQEs exceeds the maximum.
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 489 */
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 490 max_mtu_pkts = min_t(u8, MLX5E_PARAMS_MAXIMUM_LOG_RQ_SIZE,
6470d2e7e8ed8e Maxim Mikityanskiy 2022-09-29 491 mlx5e_mpwrq_max_log_rq_pkts(mdev, page_shift, unaligned));
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 492 if (params->log_rq_mtu_frames > max_mtu_pkts) {
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 493 mlx5_core_err(mdev, "Current RQ length %d is too big for XSK with given frame size %u\n",
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 494 1 << params->log_rq_mtu_frames, xsk->chunk_size);
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 495 return -EINVAL;
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 496 }
e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 497
44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 498 return 0;
b3a131c2a1602e Tariq Toukan 2021-03-07 499 }

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests


2023-01-12 07:32:11

by Tariq Toukan

[permalink] [raw]
Subject: Re: drivers/net/ethernet/mellanox/mlx5/core/en/params.c:481 mlx5e_mpwrq_validate_xsk() error: we previously assumed 'xsk' could be null (see line 478)



On 10/01/2023 7:10, Dan Carpenter wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 1fe4fd6f5cad346e598593af36caeadc4f5d4fa9
> commit: 6470d2e7e8ed8e9dd560d8dc3e09d1100a17ee26 net/mlx5e: xsk: Use KSM for unaligned XSK
> config: i386-randconfig-m021-20230102
> compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <[email protected]>
> | Reported-by: Dan Carpenter <[email protected]>
>
> New smatch warnings:
> drivers/net/ethernet/mellanox/mlx5/core/en/params.c:481 mlx5e_mpwrq_validate_xsk() error: we previously assumed 'xsk' could be null (see line 478)
>
> Old smatch warnings:
> drivers/net/ethernet/mellanox/mlx5/core/en/params.c:314 mlx5e_mpwqe_get_log_num_strides() warn: signedness bug returning '(-255)'
>
> vim +/xsk +481 drivers/net/ethernet/mellanox/mlx5/core/en/params.c
>
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 474 int mlx5e_mpwrq_validate_xsk(struct mlx5_core_dev *mdev, struct mlx5e_params *params,
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 475 struct mlx5e_xsk_param *xsk)
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 476 {
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 477 u8 page_shift = mlx5e_mpwrq_page_shift(mdev, xsk);
> 6470d2e7e8ed8e Maxim Mikityanskiy 2022-09-29 @478 bool unaligned = xsk ? xsk->unaligned : false;
> ^^^
> Assumes xsk can be NULL
>
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 479 u16 max_mtu_pkts;
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 480
> 6470d2e7e8ed8e Maxim Mikityanskiy 2022-09-29 @481 if (!mlx5e_check_fragmented_striding_rq_cap(mdev, page_shift, xsk->unaligned))
> ^^^^^
> Unchecked dereference
>
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 482 return -EOPNOTSUPP;
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 483
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 484 if (!mlx5e_rx_mpwqe_is_linear_skb(mdev, params, xsk))
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 485 return -EINVAL;
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 486
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 487 /* Current RQ length is too big for the given frame size, the
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 488 * needed number of WQEs exceeds the maximum.
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 489 */
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 490 max_mtu_pkts = min_t(u8, MLX5E_PARAMS_MAXIMUM_LOG_RQ_SIZE,
> 6470d2e7e8ed8e Maxim Mikityanskiy 2022-09-29 491 mlx5e_mpwrq_max_log_rq_pkts(mdev, page_shift, unaligned));
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 492 if (params->log_rq_mtu_frames > max_mtu_pkts) {
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 493 mlx5_core_err(mdev, "Current RQ length %d is too big for XSK with given frame size %u\n",
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 494 1 << params->log_rq_mtu_frames, xsk->chunk_size);
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 495 return -EINVAL;
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 496 }
> e5a3cc83d54019 Maxim Mikityanskiy 2022-09-29 497
> 44f4fd03b51705 Maxim Mikityanskiy 2022-09-27 498 return 0;
> b3a131c2a1602e Tariq Toukan 2021-03-07 499 }
>
Hi,

Thanks for your report.
My team is looking into it and we'll reply/fix soon.

Regards,
Tariq