diff options
author | Peilin Ye <peilin.ye@bytedance.com> | 2022-04-22 00:08:38 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-04-25 12:40:45 +0200 |
commit | fde98ae91f79cab4e020f40c35ed23cbdc59661c (patch) | |
tree | c31fe834e8fae6ea1d6e8121faa212ed1f19f18b /net | |
parent | ip_gre: Make o_seqno start from 0 in native mode (diff) | |
download | linux-fde98ae91f79cab4e020f40c35ed23cbdc59661c.tar.xz linux-fde98ae91f79cab4e020f40c35ed23cbdc59661c.zip |
ip6_gre: Make o_seqno start from 0 in native mode
For IP6GRE and IP6GRETAP 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 the "if (tunnel->parms.collect_md)" clause in __gre6_xmit(),
where tunnel->o_seqno is passed to gre_build_header() before getting
incremented.
Fixes: c12b395a4664 ("gre: Support GRE over IPv6")
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/ipv6/ip6_gre.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 976236736146..d9e4ac94eab4 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -724,6 +724,7 @@ static netdev_tx_t __gre6_xmit(struct sk_buff *skb, { struct ip6_tnl *tunnel = netdev_priv(dev); __be16 protocol; + __be16 flags; if (dev->type == ARPHRD_ETHER) IPCB(skb)->flags = 0; @@ -739,7 +740,6 @@ static netdev_tx_t __gre6_xmit(struct sk_buff *skb, if (tunnel->parms.collect_md) { struct ip_tunnel_info *tun_info; const struct ip_tunnel_key *key; - __be16 flags; int tun_hlen; tun_info = skb_tunnel_info_txcheck(skb); @@ -770,15 +770,14 @@ static netdev_tx_t __gre6_xmit(struct sk_buff *skb, : 0); } else { - if (tunnel->parms.o_flags & TUNNEL_SEQ) - tunnel->o_seqno++; - if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen)) return -ENOMEM; - gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags, + flags = tunnel->parms.o_flags; + + gre_build_header(skb, tunnel->tun_hlen, flags, protocol, tunnel->parms.o_key, - htonl(tunnel->o_seqno)); + (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++) : 0); } return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu, |