drivers/net/ethernet/intel/igb/igb_main.c:7895:6-11: ERROR: invalid reference to the index variable of the iterator on line 7890 (fwd)

From: Julia Lawall
Date: Fri Sep 13 2024 - 13:52:20 EST

On line 7895, entry is never NULL, even if you are at the end (which is
the same as the beginning) of the list.

julia

---------- Forwarded message ----------
Date: Sat, 14 Sep 2024 01:43:11 +0800
From: kernel test robot <lkp@xxxxxxxxx>
To: oe-kbuild@xxxxxxxxxxxxxxx
Cc: lkp@xxxxxxxxx, Julia Lawall <julia.lawall@xxxxxxxx>
Subject: drivers/net/ethernet/intel/igb/igb_main.c:7895:6-11: ERROR: invalid
reference to the index variable of the iterator on line 7890

BCC: lkp@xxxxxxxxx
CC: oe-kbuild-all@xxxxxxxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx
TO: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
CC: Paolo Abeni <pabeni@xxxxxxxxxx>
CC: Jacob Keller <jacob.e.keller@xxxxxxxxx>
CC: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
CC: Simon Horman <horms@xxxxxxxxxx>

Hi Jinjie,

FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 196145c606d0f816fd3926483cb1ff87e09c2c0b
commit: c1fec890458ad101ddbbc52cdd29f7bba6aa2b10 ethernet/intel: Use list_for_each_entry() helper
date: 12 months ago
:::::: branch date: 18 hours ago
:::::: commit date: 12 months ago
config: microblaze-randconfig-r052-20240913 (https://download.01.org/0day-ci/archive/20240914/202409140131.Y6Qnoc6t-lkp@xxxxxxxxx/config)
compiler: microblaze-linux-gcc (GCC) 14.1.0

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: Julia Lawall <julia.lawall@xxxxxxxx>
| Closes: https://lore.kernel.org/r/202409140131.Y6Qnoc6t-lkp@xxxxxxxxx/

cocci warnings: (new ones prefixed by >>)
>> drivers/net/ethernet/intel/igb/igb_main.c:7895:6-11: ERROR: invalid reference to the index variable of the iterator on line 7890
drivers/net/ethernet/intel/igb/igb_main.c:7895:15-20: ERROR: invalid reference to the index variable of the iterator on line 7890

vim +7895 drivers/net/ethernet/intel/igb/igb_main.c

83c21335c87622 Yury Kylulin 2017-03-07 7854
b476deab8f412b Colin Ian King 2017-04-27 7855 static int igb_set_vf_mac_filter(struct igb_adapter *adapter, const int vf,
4827cc37796a02 Yury Kylulin 2017-03-07 7856 const u32 info, const u8 *addr)
4827cc37796a02 Yury Kylulin 2017-03-07 7857 {
4827cc37796a02 Yury Kylulin 2017-03-07 7858 struct pci_dev *pdev = adapter->pdev;
4827cc37796a02 Yury Kylulin 2017-03-07 7859 struct vf_data_storage *vf_data = &adapter->vf_data[vf];
4827cc37796a02 Yury Kylulin 2017-03-07 7860 struct vf_mac_filter *entry = NULL;
4827cc37796a02 Yury Kylulin 2017-03-07 7861 int ret = 0;
4827cc37796a02 Yury Kylulin 2017-03-07 7862
1b8b062a99dc76 Corinna Vinschen 2018-01-17 7863 if ((vf_data->flags & IGB_VF_FLAG_PF_SET_MAC) &&
1b8b062a99dc76 Corinna Vinschen 2018-01-17 7864 !vf_data->trusted) {
4827cc37796a02 Yury Kylulin 2017-03-07 7865 dev_warn(&pdev->dev,
4827cc37796a02 Yury Kylulin 2017-03-07 7866 "VF %d requested MAC filter but is administratively denied\n",
4827cc37796a02 Yury Kylulin 2017-03-07 7867 vf);
4827cc37796a02 Yury Kylulin 2017-03-07 7868 return -EINVAL;
4827cc37796a02 Yury Kylulin 2017-03-07 7869 }
4827cc37796a02 Yury Kylulin 2017-03-07 7870 if (!is_valid_ether_addr(addr)) {
4827cc37796a02 Yury Kylulin 2017-03-07 7871 dev_warn(&pdev->dev,
4827cc37796a02 Yury Kylulin 2017-03-07 7872 "VF %d attempted to set invalid MAC filter\n",
4827cc37796a02 Yury Kylulin 2017-03-07 7873 vf);
4827cc37796a02 Yury Kylulin 2017-03-07 7874 return -EINVAL;
4827cc37796a02 Yury Kylulin 2017-03-07 7875 }
4827cc37796a02 Yury Kylulin 2017-03-07 7876
584af82154f56e Karen Sornek 2021-08-31 7877 switch (info) {
584af82154f56e Karen Sornek 2021-08-31 7878 case E1000_VF_MAC_FILTER_CLR:
584af82154f56e Karen Sornek 2021-08-31 7879 /* remove all unicast MAC filters related to the current VF */
c1fec890458ad1 Jinjie Ruan 2023-09-19 7880 list_for_each_entry(entry, &adapter->vf_macs.l, l) {
584af82154f56e Karen Sornek 2021-08-31 7881 if (entry->vf == vf) {
584af82154f56e Karen Sornek 2021-08-31 7882 entry->vf = -1;
584af82154f56e Karen Sornek 2021-08-31 7883 entry->free = true;
584af82154f56e Karen Sornek 2021-08-31 7884 igb_del_mac_filter(adapter, entry->vf_mac, vf);
584af82154f56e Karen Sornek 2021-08-31 7885 }
584af82154f56e Karen Sornek 2021-08-31 7886 }
584af82154f56e Karen Sornek 2021-08-31 7887 break;
584af82154f56e Karen Sornek 2021-08-31 7888 case E1000_VF_MAC_FILTER_ADD:
4827cc37796a02 Yury Kylulin 2017-03-07 7889 /* try to find empty slot in the list */
c1fec890458ad1 Jinjie Ruan 2023-09-19 @7890 list_for_each_entry(entry, &adapter->vf_macs.l, l) {
4827cc37796a02 Yury Kylulin 2017-03-07 7891 if (entry->free)
4827cc37796a02 Yury Kylulin 2017-03-07 7892 break;
4827cc37796a02 Yury Kylulin 2017-03-07 7893 }
4827cc37796a02 Yury Kylulin 2017-03-07 7894
4827cc37796a02 Yury Kylulin 2017-03-07 @7895 if (entry && entry->free) {
4827cc37796a02 Yury Kylulin 2017-03-07 7896 entry->free = false;
4827cc37796a02 Yury Kylulin 2017-03-07 7897 entry->vf = vf;
4827cc37796a02 Yury Kylulin 2017-03-07 7898 ether_addr_copy(entry->vf_mac, addr);
4827cc37796a02 Yury Kylulin 2017-03-07 7899
4827cc37796a02 Yury Kylulin 2017-03-07 7900 ret = igb_add_mac_filter(adapter, addr, vf);
4827cc37796a02 Yury Kylulin 2017-03-07 7901 ret = min_t(int, ret, 0);
4827cc37796a02 Yury Kylulin 2017-03-07 7902 } else {
4827cc37796a02 Yury Kylulin 2017-03-07 7903 ret = -ENOSPC;
4827cc37796a02 Yury Kylulin 2017-03-07 7904 }
4827cc37796a02 Yury Kylulin 2017-03-07 7905
4827cc37796a02 Yury Kylulin 2017-03-07 7906 if (ret == -ENOSPC)
4827cc37796a02 Yury Kylulin 2017-03-07 7907 dev_warn(&pdev->dev,
4827cc37796a02 Yury Kylulin 2017-03-07 7908 "VF %d has requested MAC filter but there is no space for it\n",
4827cc37796a02 Yury Kylulin 2017-03-07 7909 vf);
4827cc37796a02 Yury Kylulin 2017-03-07 7910 break;
4827cc37796a02 Yury Kylulin 2017-03-07 7911 default:
4827cc37796a02 Yury Kylulin 2017-03-07 7912 ret = -EINVAL;
4827cc37796a02 Yury Kylulin 2017-03-07 7913 break;
4827cc37796a02 Yury Kylulin 2017-03-07 7914 }
4827cc37796a02 Yury Kylulin 2017-03-07 7915
4827cc37796a02 Yury Kylulin 2017-03-07 7916 return ret;
4827cc37796a02 Yury Kylulin 2017-03-07 7917 }
4827cc37796a02 Yury Kylulin 2017-03-07 7918

:::::: The code at line 7895 was first introduced by commit
:::::: 4827cc37796a02ece7097e01dad8e08f537ac815 igb/igbvf: Add VF MAC filter request capabilities

:::::: TO: Yury Kylulin <yury.kylulin@xxxxxxxxx>
:::::: CC: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>

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