This is a note to let you know that I've just added the patch titled lan966x: Fix crash when adding interface under a lag to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: lan966x-fix-crash-when-adding-interface-under-a-lag.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b79cf074ffc924c8b207b79e493ea4eeaf3d7a54 Author: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx> Date: Tue Feb 6 13:30:54 2024 +0100 lan966x: Fix crash when adding interface under a lag [ Upstream commit 15faa1f67ab405d47789d4702f587ec7df7ef03e ] There is a crash when adding one of the lan966x interfaces under a lag interface. The issue can be reproduced like this: ip link add name bond0 type bond miimon 100 mode balance-xor ip link set dev eth0 master bond0 The reason is because when adding a interface under the lag it would go through all the ports and try to figure out which other ports are under that lag interface. And the issue is that lan966x can have ports that are NULL pointer as they are not probed. So then iterating over these ports it would just crash as they are NULL pointers. The fix consists in actually checking for NULL pointers before accessing something from the ports. Like we do in other places. Fixes: cabc9d49333d ("net: lan966x: Add lag support for lan966x") Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@xxxxxxxxxxxxxxx> Reviewed-by: Simon Horman <horms@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240206123054.3052966-1-horatiu.vultur@xxxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_lag.c b/drivers/net/ethernet/microchip/lan966x/lan966x_lag.c index 41fa2523d91d..5f2cd9a8cf8f 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_lag.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_lag.c @@ -37,19 +37,24 @@ static void lan966x_lag_set_aggr_pgids(struct lan966x *lan966x) /* Now, set PGIDs for each active LAG */ for (lag = 0; lag < lan966x->num_phys_ports; ++lag) { - struct net_device *bond = lan966x->ports[lag]->bond; + struct lan966x_port *port = lan966x->ports[lag]; int num_active_ports = 0; + struct net_device *bond; unsigned long bond_mask; u8 aggr_idx[16]; - if (!bond || (visited & BIT(lag))) + if (!port || !port->bond || (visited & BIT(lag))) continue; + bond = port->bond; bond_mask = lan966x_lag_get_mask(lan966x, bond); for_each_set_bit(p, &bond_mask, lan966x->num_phys_ports) { struct lan966x_port *port = lan966x->ports[p]; + if (!port) + continue; + lan_wr(ANA_PGID_PGID_SET(bond_mask), lan966x, ANA_PGID(p)); if (port->lag_tx_active)