From 45fa29c85117170b0508790f878b13ec6593c888 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Wed, 11 Sep 2024 11:20:58 +0200 Subject: [PATCH 1/2] bareudp: Pull inner IP header in bareudp_udp_encap_recv(). Bareudp reads the inner IP header to get the ECN value. Therefore, it needs to ensure that it's part of the skb's linear data. This is similar to the vxlan and geneve fixes for that same problem: * commit f7789419137b ("vxlan: Pull inner IP header in vxlan_rcv().") * commit 1ca1ba465e55 ("geneve: make sure to pull inner header in geneve_rx()") Fixes: 571912c69f0e ("net: UDP tunnel encapsulation module for tunnelling different protocols like MPLS, IP, NSH etc.") Signed-off-by: Guillaume Nault Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/5205940067c40218a70fbb888080466b2fc288db.1726046181.git.gnault@redhat.com Signed-off-by: Jakub Kicinski --- drivers/net/bareudp.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c index 7aca0544fb29..b4e820a123ca 100644 --- a/drivers/net/bareudp.c +++ b/drivers/net/bareudp.c @@ -68,6 +68,7 @@ static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) __be16 proto; void *oiph; int err; + int nh; bareudp = rcu_dereference_sk_user_data(sk); if (!bareudp) @@ -148,10 +149,25 @@ static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) } skb_dst_set(skb, &tun_dst->dst); skb->dev = bareudp->dev; - oiph = skb_network_header(skb); - skb_reset_network_header(skb); skb_reset_mac_header(skb); + /* Save offset of outer header relative to skb->head, + * because we are going to reset the network header to the inner header + * and might change skb->head. + */ + nh = skb_network_header(skb) - skb->head; + + skb_reset_network_header(skb); + + if (!pskb_inet_may_pull(skb)) { + DEV_STATS_INC(bareudp->dev, rx_length_errors); + DEV_STATS_INC(bareudp->dev, rx_errors); + goto drop; + } + + /* Get the outer header. */ + oiph = skb->head + nh; + if (!ipv6_mod_enabled() || family == AF_INET) err = IP_ECN_decapsulate(oiph, skb); else From c471236b2359e6b27388475dd04fff0a5e2bf922 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Wed, 11 Sep 2024 11:21:05 +0200 Subject: [PATCH 2/2] bareudp: Pull inner IP header on xmit. Both bareudp_xmit_skb() and bareudp6_xmit_skb() read their skb's inner IP header to get its ECN value (with ip_tunnel_ecn_encap()). Therefore we need to ensure that the inner IP header is part of the skb's linear data. Fixes: 571912c69f0e ("net: UDP tunnel encapsulation module for tunnelling different protocols like MPLS, IP, NSH etc.") Signed-off-by: Guillaume Nault Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/267328222f0a11519c6de04c640a4f87a38ea9ed.1726046181.git.gnault@redhat.com Signed-off-by: Jakub Kicinski --- drivers/net/bareudp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c index b4e820a123ca..e80992b4f9de 100644 --- a/drivers/net/bareudp.c +++ b/drivers/net/bareudp.c @@ -317,6 +317,9 @@ static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev, __be32 saddr; int err; + if (!skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB))) + return -EINVAL; + if (!sock) return -ESHUTDOWN; @@ -384,6 +387,9 @@ static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev, __be16 sport; int err; + if (!skb_vlan_inet_prepare(skb, skb->protocol != htons(ETH_P_TEB))) + return -EINVAL; + if (!sock) return -ESHUTDOWN;