From 3ae37eafd36694bb2d3227f60ac98fbf602470a2 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Wed, 23 Sep 2026 20:46:18 +0200 Subject: [PATCH] netfilter: flowtable: restore ieee80211 forward path Before commit 871df5007eda ("netfilter: flowtable: bail out if forward path cannot be discovered"), there was a fallback to set up a forward path in case .ndo_fill_forward_path fails or DEV_PATH_MTK_WDMA was used. Such fallback was used by commit d787a3e38f01 ("mac80211: add support for .ndo_fill_forward_path"). One possibility is to handle DEV_PATH_MTK_WDMA from the flowtable forward path discovery. However, this is only used internally by drivers to retrieve mtk_wdma information to set up hardware offload. Felix decided to use the .fill_forward_path interface for this purpose due to the lack of a better interface at that time. Add a new DEV_PATH_IEEE80211 path which is offered if the new ieee80211 flag is set on in the struct net_device_path_ctx to restore the flowtable with a ieee80211 netdevice. Handle this new DEV_PATH_IEEE80211 path just like DEV_PATH_ETHERNET and DEV_PATH_DSA, ie. this is the last netdevice in the stack. This new ieee80211 flag is implicitly unset for mtk_ppe and airoha which call dev_fill_forward_path() to retrieve a DEV_PATH_MTK_WDMA path. Fixes: 871df5007eda ("netfilter: flowtable: bail out if forward path cannot be discovered") Signed-off-by: Pablo Neira Ayuso --- include/linux/netdevice.h | 3 +++ net/mac80211/iface.c | 7 +++++++ net/netfilter/nf_flow_table_path.c | 3 +++ 3 files changed, 13 insertions(+) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 87cafc932e9e..3cff2174dc03 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -887,6 +887,7 @@ enum net_device_path_type { DEV_PATH_DSA, DEV_PATH_MTK_WDMA, DEV_PATH_TUN, + DEV_PATH_IEEE80211, }; struct net_device_path { @@ -953,6 +954,8 @@ struct net_device_path_ctx { u16 id; __be16 proto; } vlan[NET_DEVICE_PATH_VLAN_MAX]; + + bool ieee80211; }; enum tc_setup_type { diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 889c32fd8de1..c5584435fde9 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -1023,6 +1023,13 @@ static int ieee80211_netdev_fill_forward_path(struct net_device_path_ctx *ctx, struct sta_info *sta; int ret = -ENOENT; + if (ctx->ieee80211) { + path->type = DEV_PATH_IEEE80211; + path->dev = ctx->dev; + ctx->dev = NULL; + return 0; + } + sdata = IEEE80211_DEV_TO_SUB_IF(ctx->dev); local = sdata->local; diff --git a/net/netfilter/nf_flow_table_path.c b/net/netfilter/nf_flow_table_path.c index 1e55644f2edb..d90013685bf1 100644 --- a/net/netfilter/nf_flow_table_path.c +++ b/net/netfilter/nf_flow_table_path.c @@ -53,6 +53,7 @@ static int nft_dev_fill_forward_path(const struct dst_entry *dst_cache, struct net_device_path_ctx ctx = { .dev = dev, .ether_type = ether_type, + .ieee80211 = true, }; struct neighbour *n; u8 nud_state; @@ -114,6 +115,7 @@ static int nft_dev_path_info(struct net_device_path_stack *stack, path = &stack->path[i]; switch (path->type) { case DEV_PATH_ETHERNET: + case DEV_PATH_IEEE80211: case DEV_PATH_DSA: case DEV_PATH_VLAN: case DEV_PATH_PPPOE: @@ -123,6 +125,7 @@ static int nft_dev_path_info(struct net_device_path_stack *stack, memcpy(info->h_source, path->dev->dev_addr, ETH_ALEN); if (path->type == DEV_PATH_ETHERNET || + path->type == DEV_PATH_IEEE80211 || path->type == DEV_PATH_DSA) break;