[PATCH 4.14 81/91] gtp: do not confirm neighbor when do pmtu update

[Greg Kroah-Hartman]

From: Hangbin Liu <liuhangbin@xxxxxxxxx>

[ Upstream commit 6e9105c73f8d2163d12d5dfd762fd75483ed30f5 ]

When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

Although GTP only support ipv4 right now, and __ip_rt_update_pmtu() does not
call dst_confirm_neigh(), we still set it to false to keep consistency with
IPv6 code.

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reviewed-by: Guillaume Nault <gnault@xxxxxxxxxx>
Acked-by: David Ahern <dsahern@xxxxxxxxx>
Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/gtp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 9e3963f46458..d957ffdfec0f 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -545,7 +545,7 @@ static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
 		mtu = dst_mtu(&rt->dst);
 	}
 
-	rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu, true);
+	rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu, false);
 
 	if (!skb_is_gso(skb) && (iph->frag_off & htons(IP_DF)) &&
 	    mtu < ntohs(iph->tot_len)) {
-- 
2.20.1