Patch "vxlan: Pull inner IP header in vxlan_xmit_one()." has been added to the 6.9-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    vxlan: Pull inner IP header in vxlan_xmit_one().

to the 6.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     vxlan-pull-inner-ip-header-in-vxlan_xmit_one.patch
and it can be found in the queue-6.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit c2469c4cb7c9120e08d567e078d09355fe0fdab0
Author: Guillaume Nault <gnault@xxxxxxxxxx>
Date:   Wed Jun 19 15:34:57 2024 +0200

    vxlan: Pull inner IP header in vxlan_xmit_one().
    
    [ Upstream commit 31392048f55f98cb01ca709d32d06d926ab9760a ]
    
    Ensure the inner IP header is part of the skb's linear data before
    setting old_iph. Otherwise, on a non-linear skb, old_iph could point
    outside of the packet data.
    
    Unlike classical VXLAN, which always encapsulates Ethernet packets,
    VXLAN-GPE can transport IP packets directly. In that case, we need to
    look at skb->protocol to figure out if an Ethernet header is present.
    
    Fixes: d342894c5d2f ("vxlan: virtual extensible lan")
    Signed-off-by: Guillaume Nault <gnault@xxxxxxxxxx>
    Link: https://patch.msgid.link/2aa75f6fa62ac9dbe4f16ad5ba75dd04a51d4b99.1718804000.git.gnault@xxxxxxxxxx
    Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index b2d054f59f30f..49779ba3c4b7b 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -2336,7 +2336,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 	struct ip_tunnel_key *pkey;
 	struct ip_tunnel_key key;
 	struct vxlan_dev *vxlan = netdev_priv(dev);
-	const struct iphdr *old_iph = ip_hdr(skb);
+	const struct iphdr *old_iph;
 	struct vxlan_metadata _md;
 	struct vxlan_metadata *md = &_md;
 	unsigned int pkt_len = skb->len;
@@ -2350,8 +2350,15 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 	bool use_cache;
 	bool udp_sum = false;
 	bool xnet = !net_eq(vxlan->net, dev_net(vxlan->dev));
+	bool no_eth_encap;
 	__be32 vni = 0;
 
+	no_eth_encap = flags & VXLAN_F_GPE && skb->protocol != htons(ETH_P_TEB);
+	if (!skb_vlan_inet_prepare(skb, no_eth_encap))
+		goto drop;
+
+	old_iph = ip_hdr(skb);
+
 	info = skb_tunnel_info(skb);
 	use_cache = ip_tunnel_dst_cache_usable(skb, info);