On Mon, Sep 23, 2024 at 11:12:19AM +0200, Aleksandr Loktionov wrote:
> 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>
Thanks Aleksandr,
I see that:
1) All calls to i40e_add_mac_filter() and all other calls
to i40e_del_mac_filter() are already protected by
vsi->mac_filter_hash_lock.
2) i40e_del_mac_filter() already asserts that
vsi->mac_filter_hash_lock is held.
So this looks good to me.
Reviewed-by: Simon Horman <ho...@kernel.org>
...
