ipip: only increase err_count for some certain type icmp in ipip_err

t->err_count is used to count the link failure on tunnel and an err
will be reported to user socket in tx path if t->err_count is not 0.
udp socket could even return EHOSTUNREACH to users.

Since commit fd58156e45 ("IPIP: Use ip-tunneling code.") removed
the 'switch check' for icmp type in ipip_err(), err_count would be
increased by the icmp packet with ICMP_EXC_FRAGTIME code. an link
failure would be reported out due to this.

In Jianlin's case, when receiving ICMP_EXC_FRAGTIME a icmp packet,
udp netperf failed with the err:
  send_data: data send error: No route to host (errno 113)

We expect this error reported from tunnel to socket when receiving
some certain type icmp, but not ICMP_EXC_FRAGTIME, ICMP_SR_FAILED
or ICMP_PARAMETERPROB ones.

This patch is to bring 'switch check' for icmp type back to ipip_err
so that it only reports link failure for the right type icmp, just as
in ipgre_err() and ipip6_err().

Fixes: fd58156e45 ("IPIP: Use ip-tunneling code.")
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Xin Long 2017-10-26 19:19:56 +08:00 committed by David S. Miller
parent 6d9f0790af
commit f3594f0a7e
1 changed files with 42 additions and 17 deletions

View File

@ -128,43 +128,68 @@ static struct rtnl_link_ops ipip_link_ops __read_mostly;
static int ipip_err(struct sk_buff *skb, u32 info)
{
/* All the routers (except for Linux) return only
8 bytes of packet payload. It means, that precise relaying of
ICMP in the real Internet is absolutely infeasible.
* 8 bytes of packet payload. It means, that precise relaying of
* ICMP in the real Internet is absolutely infeasible.
*/
struct net *net = dev_net(skb->dev);
struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
const struct iphdr *iph = (const struct iphdr *)skb->data;
struct ip_tunnel *t;
int err;
const int type = icmp_hdr(skb)->type;
const int code = icmp_hdr(skb)->code;
struct ip_tunnel *t;
int err = 0;
switch (type) {
case ICMP_DEST_UNREACH:
switch (code) {
case ICMP_SR_FAILED:
/* Impossible event. */
goto out;
default:
/* All others are translated to HOST_UNREACH.
* rfc2003 contains "deep thoughts" about NET_UNREACH,
* I believe they are just ether pollution. --ANK
*/
break;
}
break;
case ICMP_TIME_EXCEEDED:
if (code != ICMP_EXC_TTL)
goto out;
break;
case ICMP_REDIRECT:
break;
default:
goto out;
}
err = -ENOENT;
t = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
iph->daddr, iph->saddr, 0);
if (!t)
if (!t) {
err = -ENOENT;
goto out;
}
if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
ipv4_update_pmtu(skb, dev_net(skb->dev), info,
t->parms.link, 0, iph->protocol, 0);
err = 0;
ipv4_update_pmtu(skb, net, info, t->parms.link, 0,
iph->protocol, 0);
goto out;
}
if (type == ICMP_REDIRECT) {
ipv4_redirect(skb, dev_net(skb->dev), t->parms.link, 0,
iph->protocol, 0);
err = 0;
ipv4_redirect(skb, net, t->parms.link, 0, iph->protocol, 0);
goto out;
}
if (t->parms.iph.daddr == 0)
if (t->parms.iph.daddr == 0) {
err = -ENOENT;
goto out;
}
err = 0;
if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
goto out;