4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Xin Long <lucien.xin@xxxxxxxxx>
[ Upstream commit f3594f0a7ea36661d7fd942facd7f31a64245f1a ]
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 fd58156e456d ("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: fd58156e456d ("IPIP: Use ip-tunneling code.")
Reported-by: Jianlin Shi <jishi@xxxxxxxxxx>
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/ipip.c | 58 ++++++++++++++++++++++++++++++++++++++++----------------
1 file changed, 42 insertions(+), 16 deletions(-)
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -129,42 +129,68 @@ static struct rtnl_link_ops ipip_link_op
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.
- */
+ /* 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.
+ */
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, IPPROTO_IPIP, 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,
- IPPROTO_IPIP, 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;