From: Amit Cohen amcohen@nvidia.com
[ Upstream commit 63b08b1f6834bbb0b4f7783bf63b80c8c8e9a047 ]
When processing port up/down events generated by the device's firmware, the driver protects itself from events reported for non-existent local ports, but not the CPU port (local port 0), which exists, but lacks a netdev.
This can result in a NULL pointer dereference when calling netif_carrier_{on,off}().
Fix this by bailing early when processing an event reported for the CPU port. Problem was only observed when running on top of a buggy emulator.
Fixes: 28b1987ef506 ("mlxsw: spectrum: Register CPU port with devlink") Signed-off-by: Amit Cohen amcohen@nvidia.com Signed-off-by: Ido Schimmel idosch@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/mellanox/mlxsw/spectrum.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c index 250c5a24264dc..edfdd44de579c 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c @@ -2131,7 +2131,7 @@ static void mlxsw_sp_pude_event_func(const struct mlxsw_reg_info *reg, max_ports = mlxsw_core_max_ports(mlxsw_sp->core); local_port = mlxsw_reg_pude_local_port_get(pude_pl);
- if (WARN_ON_ONCE(local_port >= max_ports)) + if (WARN_ON_ONCE(!local_port || local_port >= max_ports)) return; mlxsw_sp_port = mlxsw_sp->ports[local_port]; if (!mlxsw_sp_port)