generic l2tp: drop flow hash on forward

[openwrt/openwrt.git] / target / linux / generic / pending-5.15 / 778-net-l2tp-drop-flow-hash-on-forward.patch

diff --git a/target/linux/generic/pending-5.15/778-net-l2tp-drop-flow-hash-on-forward.patch b/target/linux/generic/pending-5.15/778-net-l2tp-drop-flow-hash-on-forward.patch
new file mode 100644 (file)
index 0000000..a2c0edc
--- /dev/null
+++ b/target/linux/generic/pending-5.15/778-net-l2tp-drop-flow-hash-on-forward.patch
@@ -0,0 +1,31 @@
+From 4a44a52f16ccd3d03e0cb5fb437a5eb31a5f9f05 Mon Sep 17 00:00:00 2001
+From: David Bauer <mail@david-bauer.net>
+Date: Mon, 26 Feb 2024 21:39:34 +0100
+Subject: [PATCH] net l2tp: drop flow hash on forward
+
+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.
+
+Signed-off-by: David Bauer <mail@david-bauer.net>
+---
+ net/l2tp/l2tp_eth.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+--- a/net/l2tp/l2tp_eth.c
++++ b/net/l2tp/l2tp_eth.c
+@@ -136,6 +136,9 @@ static void l2tp_eth_dev_recv(struct l2t
+       /* checksums verified by L2TP */
+       skb->ip_summed = CHECKSUM_NONE;
+ 
++      /* drop outer flow-hash */
++      skb_clear_hash(skb);
++
+       skb_dst_drop(skb);
+       nf_reset_ct(skb);
+