[PATCH AUTOSEL for 4.9 44/54] gtp: clear DF bit on GTP packet tx

From: alexander . levin
Date: Wed Nov 22 2017 - 18:14:40 EST


From: Andreas Schultz <aschultz@xxxxxxxx>

[ Upstream commit c6ce1d08eede4c2968ed08aafa3165e8e183c5a1 ]

3GPP TS 29.281 and 3GPP TS 29.060 imply that GTP-U packets should be
sent with the DF bit cleared. For example 3GPP TS 29.060, Release 8,
Section 13.2.2:

> Backbone router: Any router in the backbone may fragment the GTP
> packet if needed, according to IPv4.

Signed-off-by: Andreas Schultz <aschultz@xxxxxxxx>
Acked-by: Harald Welte <laforge@xxxxxxxxxxxxx>
Acked-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
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 cebde074d196..5b67f8a8b79a 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -612,7 +612,7 @@ static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
pktinfo.fl4.saddr, pktinfo.fl4.daddr,
pktinfo.iph->tos,
ip4_dst_hoplimit(&pktinfo.rt->dst),
- htons(IP_DF),
+ 0,
pktinfo.gtph_port, pktinfo.gtph_port,
true, false);
break;
--
2.11.0