From: Li Zetao <lizetao1@huawei.com>
Date: Mon, 14 Aug 2023 15:23:42 +0800
Subject: net/mlx5: Devcom, only use devcom after NULL check in
mlx5_devcom_send_event()
Patch-mainline: v6.6-rc1
Git-commit: 7d7c6e8c5fe4e8cceea7f66e93cee1c951670836
References: jsc#PED-3311
There is a warning reported by kernel test robot:
smatch warnings:
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c:264
mlx5_devcom_send_event() warn: variable dereferenced before
IS_ERR check devcom (see line 259)
The reason for the warning is that the pointer is used before check, put
the assignment to comp after devcom check to silence the warning.
Fixes: 88d162b47981 ("net/mlx5: Devcom, Infrastructure changes")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202308041028.AkXYDwJ6-lkp@intel.com/
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/devcom.c
@@ -256,14 +256,15 @@ int mlx5_devcom_send_event(struct mlx5_d
int event, int rollback_event,
void *event_data)
{
- struct mlx5_devcom_comp *comp = devcom->comp;
struct mlx5_devcom_comp_dev *pos;
+ struct mlx5_devcom_comp *comp;
int err = 0;
void *data;
if (IS_ERR_OR_NULL(devcom))
return -ENODEV;
+ comp = devcom->comp;
down_write(&comp->sem);
list_for_each_entry(pos, &comp->comp_dev_list_head, list) {
data = rcu_dereference_protected(pos->data, lockdep_is_held(&comp->sem));