From: "Leon M. Busch-George" Date: Sun, 20 Oct 2024 18:20:14 +0200 Subject: [PATCH] net: bridge: switchdev: Don't drop packets between ports with no hwdom nbp_switchdev_allowed_egress uses hwdom to determine whether or not a packet has already been forwarded to a hardware domain. For net_bridge_ports that aren't set up to use forward offloading, hwdom is set to 0. When both ingress and egress port have no hwdom, 'cb->src_hwdom != p->hwdom' indicates that the packet is already known in the target domain - which it isn't - and the packet is wrongly dropped. The error was found on a bridge containing a wifi device and a VLAN tagging device (e.g. eth0.12). With VLAN filtering, this shouldn't happen. This patch adds a check for p->hwdom != 0 before comparing hardware domains to restore forwarding between ports with hwdom = 0. fwd_hwdoms are only set for ports with offloading enabled, which also implies a valid hwdom, so the check '!test_bit(p->hwdom, &cb->fwd_hwdoms)' doesn't fail in this way (yet - fingers crossed..) and it is left in place. Co-developed-by: Felix Fietkau Signed-off-by: Felix Fietkau Signed-off-by: Leon M. Busch-George --- --- a/net/bridge/br_switchdev.c +++ b/net/bridge/br_switchdev.c @@ -67,7 +67,7 @@ bool nbp_switchdev_allowed_egress(const struct br_input_skb_cb *cb = BR_INPUT_SKB_CB(skb); return !test_bit(p->hwdom, &cb->fwd_hwdoms) && - (!skb->offload_fwd_mark || cb->src_hwdom != p->hwdom); + (!skb->offload_fwd_mark || !p->hwdom || cb->src_hwdom != p->hwdom); } /* Flags that can be offloaded to hardware */