From edaab33273c70066a73455dae964310a7fd1c2b4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= Date: Wed, 29 Apr 2020 14:59:22 -0600 Subject: [PATCH] UPSTREAM: wireguard: receive: use tunnel helpers for decapsulating ECN markings MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit WireGuard currently only propagates ECN markings on tunnel decap according to the old RFC3168 specification. However, the spec has since been updated in RFC6040 to recommend slightly different decapsulation semantics. This was implemented in the kernel as a set of common helpers for ECN decapsulation, so let's just switch over WireGuard to using those, so it can benefit from this enhancement and any future tweaks. We do not drop packets with invalid ECN marking combinations, because WireGuard is frequently used to work around broken ISPs, which could be doing that. Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Reported-by: Olivier Tilmans Cc: Dave Taht Cc: Rodney W. Grimes Signed-off-by: Toke Høiland-Jørgensen Change-Id: Ie817ef741409c58ebc920f1497a759995159f3df Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller (cherry picked from commit eebabcb26ea1e3295704477c6cd4e772c96a9559) Bug: 152722841 Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 023967470683d1097f2bd957c489998fdd08da21) Signed-off-by: TogoFire --- drivers/net/wireguard/receive.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireguard/receive.c b/drivers/net/wireguard/receive.c index da3b782ab7d3..267f202f1931 100644 --- a/drivers/net/wireguard/receive.c +++ b/drivers/net/wireguard/receive.c @@ -393,13 +393,11 @@ static void wg_packet_consume_data_done(struct wg_peer *peer, len = ntohs(ip_hdr(skb)->tot_len); if (unlikely(len < sizeof(struct iphdr))) goto dishonest_packet_size; - if (INET_ECN_is_ce(PACKET_CB(skb)->ds)) - IP_ECN_set_ce(ip_hdr(skb)); + INET_ECN_decapsulate(skb, PACKET_CB(skb)->ds, ip_hdr(skb)->tos); } else if (skb->protocol == htons(ETH_P_IPV6)) { len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr); - if (INET_ECN_is_ce(PACKET_CB(skb)->ds)) - IP6_ECN_set_ce(skb, ipv6_hdr(skb)); + INET_ECN_decapsulate(skb, PACKET_CB(skb)->ds, ipv6_get_dsfield(ipv6_hdr(skb))); } else { goto dishonest_packet_type; }