When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a bogus pointer
computed based on the head element.

While it is safe to use the pointer to determine if it was computed
based on the head element, either with list_entry_is_head() or
&pos->member == head, using the iterator variable after the loop should
be avoided.

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].

Link: 
https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=ehreask5sqxpwr9y7k9sa6cwx...@mail.gmail.com/
 [1]
Signed-off-by: Jakob Koschel <jakobkosc...@gmail.com>
---
 drivers/net/ethernet/qlogic/qede/qede_filter.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/qlogic/qede/qede_filter.c 
b/drivers/net/ethernet/qlogic/qede/qede_filter.c
index 3010833ddde3..3d167e37e654 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_filter.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_filter.c
@@ -829,18 +829,21 @@ int qede_configure_vlan_filters(struct qede_dev *edev)
 int qede_vlan_rx_kill_vid(struct net_device *dev, __be16 proto, u16 vid)
 {
        struct qede_dev *edev = netdev_priv(dev);
-       struct qede_vlan *vlan;
+       struct qede_vlan *vlan = NULL;
+       struct qede_vlan *iter;
        int rc = 0;
 
        DP_VERBOSE(edev, NETIF_MSG_IFDOWN, "Removing vlan 0x%04x\n", vid);
 
        /* Find whether entry exists */
        __qede_lock(edev);
-       list_for_each_entry(vlan, &edev->vlan_list, list)
-               if (vlan->vid == vid)
+       list_for_each_entry(iter, &edev->vlan_list, list)
+               if (iter->vid == vid) {
+                       vlan = iter;
                        break;
+               }
 
-       if (list_entry_is_head(vlan, &edev->vlan_list, list)) {
+       if (!vlan) {
                DP_VERBOSE(edev, (NETIF_MSG_IFUP | NETIF_MSG_IFDOWN),
                           "Vlan isn't configured\n");
                goto out;
-- 
2.25.1

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