[Intel-wired-lan] [PATCH iwl-net v1] i40e: Fix macvlan leak by synchronizing access to mac_filter_hash

[Aleksandr Loktionov]

This patch addresses a macvlan leak issue in the i40e driver caused by
concurrent access to vsi->mac_filter_hash. The leak occurs when multiple
threads attempt to modify the mac_filter_hash simultaneously, leading to
inconsistent state and potential memory leaks.

To fix this, we now wrap the calls to i40e_del_mac_filter() and zeroing
vf->default_lan_addr.addr with spin_lock/unlock_bh(&vsi->mac_filter_hash_lock),
ensuring atomic operations and preventing concurrent access.

Additionally, we add lockdep_assert_held(&vsi->mac_filter_hash_lock) in
i40e_add_mac_filter() to help catch similar issues in the future.

Reproduction steps:
1. Spawn VFs and configure port vlan on them.
2. Trigger concurrent macvlan operations (e.g., adding and deleting
        portvlan and/or mac filters).
3. Observe the potential memory leak and inconsistent state in the
        mac_filter_hash.

This synchronization ensures the integrity of the mac_filter_hash and prevents
the described leak.

Fixes: fed0d9f13266 ("i40e: Fix VF's MAC Address change on VM")
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalew...@intel.com>
Signed-off-by: Aleksandr Loktionov <aleksandr.loktio...@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c        | 1 +
 drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c 
b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 03205eb..25295ae 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -1734,6 +1734,7 @@ struct i40e_mac_filter *i40e_add_mac_filter(struct 
i40e_vsi *vsi,
        struct hlist_node *h;
        int bkt;
 
+       lockdep_assert_held(&vsi->mac_filter_hash_lock);
        if (vsi->info.pvid)
                return i40e_add_filter(vsi, macaddr,
                                       le16_to_cpu(vsi->info.pvid));
diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c 
b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
index 662622f..dfa785e 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -2213,8 +2213,10 @@ static int i40e_vc_get_vf_resources_msg(struct i40e_vf 
*vf, u8 *msg)
                vfres->vsi_res[0].qset_handle
                                          = le16_to_cpu(vsi->info.qs_handle[0]);
                if (!(vf->driver_caps & VIRTCHNL_VF_OFFLOAD_USO) && 
!vf->pf_set_mac) {
+                       spin_lock_bh(&vsi->mac_filter_hash_lock);
                        i40e_del_mac_filter(vsi, vf->default_lan_addr.addr);
                        eth_zero_addr(vf->default_lan_addr.addr);
+                       spin_unlock_bh(&vsi->mac_filter_hash_lock);
                }
                ether_addr_copy(vfres->vsi_res[0].default_mac_addr,
                                vf->default_lan_addr.addr);
-- 
2.25.1