This is a note to let you know that I've just added the patch titled net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave() to the 5.13-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: net-dsa-properly-check-for-the-bridge_leave-methods-in-dsa_switch_bridge_leave.patch and it can be found in the queue-5.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From bcb9928a155444dbd212473e60241ca0a7f641e1 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean <vladimir.oltean@xxxxxxx> Date: Tue, 13 Jul 2021 12:40:21 +0300 Subject: net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave() From: Vladimir Oltean <vladimir.oltean@xxxxxxx> commit bcb9928a155444dbd212473e60241ca0a7f641e1 upstream. This was not caught because there is no switch driver which implements the .port_bridge_join but not .port_bridge_leave method, but it should nonetheless be fixed, as in certain conditions (driver development) it might lead to NULL pointer dereference. Fixes: f66a6a69f97a ("net: dsa: permit cross-chip bridging between all trees in the system") Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/dsa/switch.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/dsa/switch.c +++ b/net/dsa/switch.c @@ -110,11 +110,11 @@ static int dsa_switch_bridge_leave(struc int err, port; if (dst->index == info->tree_index && ds->index == info->sw_index && - ds->ops->port_bridge_join) + ds->ops->port_bridge_leave) ds->ops->port_bridge_leave(ds, info->port, info->br); if ((dst->index != info->tree_index || ds->index != info->sw_index) && - ds->ops->crosschip_bridge_join) + ds->ops->crosschip_bridge_leave) ds->ops->crosschip_bridge_leave(ds, info->tree_index, info->sw_index, info->port, info->br); Patches currently in stable-queue which might be from vladimir.oltean@xxxxxxx are queue-5.13/net-dsa-properly-check-for-the-bridge_leave-methods-in-dsa_switch_bridge_leave.patch