gtp: clear DF bit on GTP packet tx

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@tpip.net>
Acked-by: Harald Welte <laforge@netfilter.org>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 7580ccc50e1d45c8931c990b3a31ed3233ea4433..1df54d626f2097be24db14ed360f388444e54f53 100644 (file)
--- 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;