From: Amir Tzin <amirtz@nvidia.com>
Date: Sun, 8 Jan 2023 15:54:46 +0200
Subject: net/mlx5e: Fix crash unsetting rx-vlan-filter in switchdev mode
Patch-mainline: v6.2-rc8
Git-commit: 8974aa9638df557f4642acef707af15648a03555
References: jsc#PED-1549

Moving to switchdev mode with rx-vlan-filter on and then setting it off
causes the kernel to crash since fs->vlan is freed during nic profile
cleanup flow.

RX VLAN filtering is not supported in switchdev mode so unset it when
changing to switchdev and restore its value when switching back to
legacy.

trace:
[] RIP: 0010:mlx5e_disable_cvlan_filter+0x43/0x70
[] set_feature_cvlan_filter+0x37/0x40 [mlx5_core]
[] mlx5e_handle_feature+0x3a/0x60 [mlx5_core]
[] mlx5e_set_features+0x6d/0x160 [mlx5_core]
[] __netdev_update_features+0x288/0xa70
[] ethnl_set_features+0x309/0x380
[] ? __nla_parse+0x21/0x30
[] genl_family_rcv_msg_doit.isra.17+0x110/0x150
[] genl_rcv_msg+0x112/0x260
[] ? features_reply_size+0xe0/0xe0
[] ? genl_family_rcv_msg_doit.isra.17+0x150/0x150
[] netlink_rcv_skb+0x4e/0x100
[] genl_rcv+0x24/0x40
[] netlink_unicast+0x1ab/0x290
[] netlink_sendmsg+0x257/0x4f0
[] sock_sendmsg+0x5c/0x70

Fixes: cb67b832921c ("net/mlx5e: Introduce SRIOV VF representors")
Signed-off-by: Amir Tzin <amirtz@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_fs.c   |    2 +-
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c |    4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c
@@ -443,7 +443,7 @@ void mlx5e_enable_cvlan_filter(struct ml
 
 void mlx5e_disable_cvlan_filter(struct mlx5e_flow_steering *fs, bool promisc)
 {
-	if (fs->vlan->cvlan_filter_disabled)
+	if (!fs->vlan || fs->vlan->cvlan_filter_disabled)
 		return;
 
 	fs->vlan->cvlan_filter_disabled = true;
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -4005,6 +4005,10 @@ static netdev_features_t mlx5e_fix_uplin
 	if (netdev->features & NETIF_F_GRO_HW)
 		netdev_warn(netdev, "Disabling HW_GRO, not supported in switchdev mode\n");
 
+	features &= ~NETIF_F_HW_VLAN_CTAG_FILTER;
+	if (netdev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
+		netdev_warn(netdev, "Disabling HW_VLAN CTAG FILTERING, not supported in switchdev mode\n");
+
 	return features;
 }