4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 993107fea5eefdfdfde1ca38d3f01f0bebf76e77 ]
When deleting a VLAN device using an ioctl the netdev is unregistered before the VLAN filter is updated via ndo_vlan_rx_kill_vid(). It can lead to a use-after-free in mlxsw in case the VLAN device is deleted while being enslaved to a bridge.
The reason for the above is that when mlxsw receives the CHANGEUPPER event, it wrongly assumes that the VLAN device is no longer its upper and thus destroys the internal representation of the bridge port despite the reference count being non-zero.
Fix this by checking if the VLAN device is our upper using its real device. In net-next I'm going to remove this trick and instead make mlxsw completely agnostic to the order of the events.
Fixes: c57529e1d5d8 ("mlxsw: spectrum: Replace vPorts with Port-VLAN") Signed-off-by: Ido Schimmel idosch@mellanox.com Reviewed-by: Petr Machata petrm@mellanox.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/mellanox/mlxsw/spectrum_switchdev.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c index 7715f1ed2bcb..4eb64cb0d9a1 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c @@ -286,7 +286,13 @@ static bool mlxsw_sp_bridge_port_should_destroy(const struct mlxsw_sp_bridge_port * bridge_port) { - struct mlxsw_sp *mlxsw_sp = mlxsw_sp_lower_get(bridge_port->dev); + struct net_device *dev = bridge_port->dev; + struct mlxsw_sp *mlxsw_sp; + + if (is_vlan_dev(dev)) + mlxsw_sp = mlxsw_sp_lower_get(vlan_dev_real_dev(dev)); + else + mlxsw_sp = mlxsw_sp_lower_get(dev);
/* In case ports were pulled from out of a bridged LAG, then * it's possible the reference count isn't zero, yet the bridge @@ -2020,7 +2026,7 @@ mlxsw_sp_bridge_8021d_port_leave(struct mlxsw_sp_bridge_device *bridge_device,
vid = is_vlan_dev(dev) ? vlan_dev_vlan_id(dev) : 1; mlxsw_sp_port_vlan = mlxsw_sp_port_vlan_find_by_vid(mlxsw_sp_port, vid); - if (WARN_ON(!mlxsw_sp_port_vlan)) + if (!mlxsw_sp_port_vlan) return;
mlxsw_sp_port_vlan_bridge_leave(mlxsw_sp_port_vlan);