From: Guillaume Nault Date: Mon, 10 Jan 2022 13:43:09 +0000 (+0100) Subject: gre: Don't accidentally set RTO_ONLINK in gre_fill_metadata_dst() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=09c0535c768de9429a15c522007dfc8e96a428f8;p=linux.git gre: Don't accidentally set RTO_ONLINK in gre_fill_metadata_dst() commit f7716b318568b22fbf0e3be99279a979e217cf71 upstream. Mask the ECN bits before initialising ->flowi4_tos. The tunnel key may have the last ECN bit set, which will interfere with the route lookup process as ip_route_output_key_hash() interpretes this bit specially (to restrict the route scope). Found by code inspection, compile tested only. Fixes: 962924fa2b7a ("ip_gre: Refactor collect metatdata mode tunnel xmit to ip_md_tunnel_xmit") Signed-off-by: Guillaume Nault Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 0fe6c936dc54a..e7f3e37e4aa83 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -604,8 +604,9 @@ static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) key = &info->key; ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src, - tunnel_id_to_key32(key->tun_id), key->tos, 0, - skb->mark, skb_get_hash(skb)); + tunnel_id_to_key32(key->tun_id), + key->tos & ~INET_ECN_MASK, 0, skb->mark, + skb_get_hash(skb)); rt = ip_route_output_key(dev_net(dev), &fl4); if (IS_ERR(rt)) return PTR_ERR(rt);