From d9db25723677c3741a0cf3643f7f7429fc983921 Mon Sep 17 00:00:00 2001 From: Ovidiu Panait Date: Thu, 13 Nov 2025 11:27:20 +0000 Subject: [PATCH] net: stmmac: Fix VLAN 0 deletion in vlan_del_hw_rx_fltr() When the "rx-vlan-filter" feature is enabled on a network device, the 8021q module automatically adds a VLAN 0 hardware filter when the device is brought administratively up. For stmmac, this causes vlan_add_hw_rx_fltr() to create a new entry for VID 0 in the mac_device_info->vlan_filter array, in the following format: VLAN_TAG_DATA_ETV | VLAN_TAG_DATA_VEN | vid Here, VLAN_TAG_DATA_VEN indicates that the hardware filter is enabled for that VID. However, on the delete path, vlan_del_hw_rx_fltr() searches the vlan_filter array by VID only, without verifying whether a VLAN entry is enabled. As a result, when the 8021q module attempts to remove VLAN 0, the function may mistakenly match a zero-initialized slot rather than the actual VLAN 0 entry, causing incorrect deletions and leaving stale entries in the hardware table. Fix this by verifying that the VLAN entry's enable bit (VLAN_TAG_DATA_VEN) is set before matching and deleting by VID. This ensures only active VLAN entries are removed and avoids leaving stale entries in the VLAN filter table, particularly for VLAN ID 0. Fixes: ed64639bc1e08 ("net: stmmac: Add support for VLAN Rx filtering") Signed-off-by: Ovidiu Panait Reviewed-by: Maxime Chevallier Link: https://patch.msgid.link/20251113112721.70500-2-ovidiu.panait.rb@renesas.com Signed-off-by: Paolo Abeni --- drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c index ff02a79c00d4f..b18404dd5a8be 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c @@ -122,7 +122,8 @@ static int vlan_del_hw_rx_fltr(struct net_device *dev, /* Extended Rx VLAN Filter Enable */ for (i = 0; i < hw->num_vlan; i++) { - if ((hw->vlan_filter[i] & VLAN_TAG_DATA_VID) == vid) { + if ((hw->vlan_filter[i] & VLAN_TAG_DATA_VEN) && + ((hw->vlan_filter[i] & VLAN_TAG_DATA_VID) == vid)) { ret = vlan_write_filter(dev, hw, i, 0); if (!ret) -- 2.47.3