summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorPeilin Ye <peilin.ye@bytedance.com>2022-04-21 15:07:57 -0700
committerDavid S. Miller <davem@davemloft.net>2022-04-25 11:40:45 +0100
commitff827beb706ed719c766acf36449801ded0c17fc (patch)
tree709a0dc47a77937982fc939a5f6d5b10463ba208 /net
parent9810c58c7051ae83e7ac326fca3daa823da6b778 (diff)
ip_gre: Make o_seqno start from 0 in native mode
For GRE and GRETAP devices, currently o_seqno starts from 1 in native mode. According to RFC 2890 2.2., "The first datagram is sent with a sequence number of 0." Fix it. It is worth mentioning that o_seqno already starts from 0 in collect_md mode, see gre_fb_xmit(), where tunnel->o_seqno is passed to gre_build_header() before getting incremented. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Peilin Ye <peilin.ye@bytedance.com> Acked-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/ip_gre.c8
1 files changed, 3 insertions, 5 deletions
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 365caebf51ab..21a8943f6fa4 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -459,14 +459,12 @@ static void __gre_xmit(struct sk_buff *skb, struct net_device *dev,
__be16 proto)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
-
- if (tunnel->parms.o_flags & TUNNEL_SEQ)
- tunnel->o_seqno++;
+ __be16 flags = tunnel->parms.o_flags;
/* Push GRE header. */
gre_build_header(skb, tunnel->tun_hlen,
- tunnel->parms.o_flags, proto, tunnel->parms.o_key,
- htonl(tunnel->o_seqno));
+ flags, proto, tunnel->parms.o_key,
+ (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) : 0);
ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol);
}