[PATCH net 2/4] net: lan966x: Fix IGMP snooping when frames have vlan tag

From: Horatiu Vultur
Date: Sat Apr 09 2022 - 14:39:27 EST


In case an IGMP frame has a vlan tag, then the function
lan966x_hw_offload couldn't figure out that is a IGMP frame. Therefore
the SW thinks that the frame was already forward by the HW which is not
true.
Extend lan966x_hw_offload to pop the vlan tag if are any and then check
for IGMP frames.

Fixes: 47aeea0d57e80c ("net: lan966x: Implement the callback SWITCHDEV_ATTR_ID_BRIDGE_MC_DISABLED ")
Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
---
drivers/net/ethernet/microchip/lan966x/lan966x_main.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
index 1f8c67f0261b..958e55596b82 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
@@ -446,6 +446,12 @@ static bool lan966x_hw_offload(struct lan966x *lan966x, u32 port,
ANA_CPU_FWD_CFG_MLD_REDIR_ENA)))
return true;

+ if (eth_type_vlan(skb->protocol)) {
+ skb = skb_vlan_untag(skb);
+ if (unlikely(!skb))
+ return false;
+ }
+
if (skb->protocol == htons(ETH_P_IP) &&
ip_hdr(skb)->protocol == IPPROTO_IGMP)
return false;
--
2.33.0