netfilter: flowtable: restore ieee80211 forward path

Before commit 871df5007e ("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 d787a3e38f ("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: 871df5007e ("netfilter: flowtable: bail out if forward path cannot be discovered")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Pablo Neira Ayuso 2026-09-23 20:46:18 +02:00
commit 3ae37eafd3
3 changed files with 13 additions and 0 deletions