From: David Bauer mail@david-bauer.net
stable inclusion from stable-v4.19.314 commit b6e4b93edc0100a88d7d4f3140bba25a529c5166 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IA7IEQ
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
--------------------------------
[ Upstream commit 42f853b42899d9b445763b55c3c8adc72be0f0e1 ]
Drop the flow-hash of the skb when forwarding to the L2TP netdev.
This avoids the L2TP qdisc from using the flow-hash from the outer packet, which is identical for every flow within the tunnel.
This does not affect every platform but is specific for the ethernet driver. It depends on the platform including L4 information in the flow-hash.
One such example is the Mediatek Filogic MT798x family of networking processors.
Fixes: d9e31d17ceba ("l2tp: Add L2TP ethernet pseudowire support") Acked-by: James Chapman jchapman@katalix.com Signed-off-by: David Bauer mail@david-bauer.net Reviewed-by: Simon Horman horms@kernel.org Link: https://lore.kernel.org/r/20240424171110.13701-1-mail@david-bauer.net Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zhengchao Shao shaozhengchao@huawei.com --- net/l2tp/l2tp_eth.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c index 8aadc4f3bb9e..b0d520c8bdfd 100644 --- a/net/l2tp/l2tp_eth.c +++ b/net/l2tp/l2tp_eth.c @@ -154,6 +154,9 @@ static void l2tp_eth_dev_recv(struct l2tp_session *session, struct sk_buff *skb, /* checksums verified by L2TP */ skb->ip_summed = CHECKSUM_NONE;
+ /* drop outer flow-hash */ + skb_clear_hash(skb); + skb_dst_drop(skb); nf_reset(skb);