diff mbox series

[5.16,0991/1039] gre: Dont accidentally set RTO_ONLINK in gre_fill_metadata_dst()

Message ID 20220124184158.599754506@linuxfoundation.org
State Superseded
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman Jan. 24, 2022, 6:46 p.m. UTC
From: Guillaume Nault <gnault@redhat.com>

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 <gnault@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/ip_gre.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -604,8 +604,9 @@  static int gre_fill_metadata_dst(struct
 
 	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);