drivers/net/ethernet/huawei/hinic/hinic_port.c:459 hinic_set_vlan_fliter() warn: variable dereferenced before check 'hwdev' (see line 453)

[Dan Carpenter]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   0bb80ecc33a8fb5a682236443c1e740d5c917d1d
commit: 2acf960e3be6177f437baade6d1883ebe4c641b2 net: hinic: Add support for configuration of rx-vlan-filter by ethtool
config: x86_64-randconfig-161-20230911 (https://download.01.org/0day-ci/archive/20230911/202309112354.pikZCmyk-lkp@xxxxxxxxx/config)
compiler: gcc-11 (Debian 11.3.0-12) 11.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230911/202309112354.pikZCmyk-lkp@xxxxxxxxx/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
| Closes: https://lore.kernel.org/r/202309112354.pikZCmyk-lkp@xxxxxxxxx/

smatch warnings:
drivers/net/ethernet/huawei/hinic/hinic_port.c:459 hinic_set_vlan_fliter() warn: variable dereferenced before check 'hwdev' (see line 453)

vim +/hwdev +459 drivers/net/ethernet/huawei/hinic/hinic_port.c

2acf960e3be617 Cai Huoqing  2022-11-03  450  int hinic_set_vlan_fliter(struct hinic_dev *nic_dev, u32 en)
2acf960e3be617 Cai Huoqing  2022-11-03  451  {
2acf960e3be617 Cai Huoqing  2022-11-03  452  	struct hinic_hwdev *hwdev = nic_dev->hwdev;
2acf960e3be617 Cai Huoqing  2022-11-03 @453  	struct hinic_hwif *hwif = hwdev->hwif;
                                                                          ^^^^^^^
Dereference

2acf960e3be617 Cai Huoqing  2022-11-03  454  	struct pci_dev *pdev = hwif->pdev;
2acf960e3be617 Cai Huoqing  2022-11-03  455  	struct hinic_vlan_filter vlan_filter;
2acf960e3be617 Cai Huoqing  2022-11-03  456  	u16 out_size = sizeof(vlan_filter);
2acf960e3be617 Cai Huoqing  2022-11-03  457  	int err;
2acf960e3be617 Cai Huoqing  2022-11-03  458  
2acf960e3be617 Cai Huoqing  2022-11-03 @459  	if (!hwdev)
                                                    ^^^^^^
Checked too late.

2acf960e3be617 Cai Huoqing  2022-11-03  460  		return -EINVAL;
2acf960e3be617 Cai Huoqing  2022-11-03  461  
2acf960e3be617 Cai Huoqing  2022-11-03  462  	vlan_filter.func_idx = HINIC_HWIF_FUNC_IDX(hwif);
2acf960e3be617 Cai Huoqing  2022-11-03  463  	vlan_filter.enable = en;
2acf960e3be617 Cai Huoqing  2022-11-03  464  
2acf960e3be617 Cai Huoqing  2022-11-03  465  	err = hinic_port_msg_cmd(hwdev, HINIC_PORT_CMD_SET_VLAN_FILTER,

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