When we exit a list_for_each_entry() without hitting a break statement, the list iterator isn't NULL, it just point to an offset off the list_head. In that situation, it wouldn't be too surprising for entry->free to be true and we end up corrupting memory. The way to test for these is to just set a flag. Fixes: c1fec890458a ("ethernet/intel: Use list_for_each_entry() helper") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> --- drivers/net/ethernet/intel/igb/igb_main.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 2ac9dffd0bf8..c45b1e7cde58 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -7857,7 +7857,8 @@ static int igb_set_vf_mac_filter(struct igb_adapter *adapter, const int vf, { struct pci_dev *pdev = adapter->pdev; struct vf_data_storage *vf_data = &adapter->vf_data[vf]; - struct vf_mac_filter *entry = NULL; + struct vf_mac_filter *entry; + bool found = false; int ret = 0; if ((vf_data->flags & IGB_VF_FLAG_PF_SET_MAC) && @@ -7888,11 +7889,13 @@ static int igb_set_vf_mac_filter(struct igb_adapter *adapter, const int vf, case E1000_VF_MAC_FILTER_ADD: /* try to find empty slot in the list */ list_for_each_entry(entry, &adapter->vf_macs.l, l) { - if (entry->free) + if (entry->free) { + found = true; break; + } } - if (entry && entry->free) { + if (found) { entry->free = false; entry->vf = vf; ether_addr_copy(entry->vf_mac, addr); -- 2.39.2