diff options
| author |   Francesco Ruggeri <fruggeri@arista.com> | 2019-10-31 17:44:13 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2019-11-03 17:25:18 -0800 |
| commit | 2adf81c0f7b04f9f10e55f5634b1eb7e0a783276 (patch) | |
| tree | 4f56f0697f2f8734d96576aeb40d5124001d3509 /net/ipv4 | |
| parent | Merge branch 'optimize-openvswitch-flow-looking-up' (diff) | |
| download | linux-dev-2adf81c0f7b04f9f10e55f5634b1eb7e0a783276.tar.xz linux-dev-2adf81c0f7b04f9f10e55f5634b1eb7e0a783276.zip | |
net: icmp: use input address in traceroute
Even with icmp_errors_use_inbound_ifaddr set, traceroute returns the
primary address of the interface the packet was received on, even if
the path goes through a secondary address. In the example:
1.0.3.1/24
---- 1.0.1.3/24 1.0.1.1/24 ---- 1.0.2.1/24 1.0.2.4/24 ----
|H1|--------------------------|R1|--------------------------|H2|
---- N1 ---- N2 ----
where 1.0.3.1/24 is R1's primary address on N1, traceroute from
H1 to H2 returns:
traceroute to 1.0.2.4 (1.0.2.4), 30 hops max, 60 byte packets
1 1.0.3.1 (1.0.3.1) 0.018 ms 0.006 ms 0.006 ms
2 1.0.2.4 (1.0.2.4) 0.021 ms 0.007 ms 0.007 ms
After applying this patch, it returns:
traceroute to 1.0.2.4 (1.0.2.4), 30 hops max, 60 byte packets
1 1.0.1.1 (1.0.1.1) 0.033 ms 0.007 ms 0.006 ms
2 1.0.2.4 (1.0.2.4) 0.011 ms 0.007 ms 0.007 ms
Original-patch-by: Bill Fenner <fenner@arista.com>
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/icmp.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 4298aae74e0e..a72fbdf1fb85 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -682,7 +682,8 @@ void __icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info, dev = dev_get_by_index_rcu(net, inet_iif(skb_in)); if (dev) - saddr = inet_select_addr(dev, 0, RT_SCOPE_LINK); + saddr = inet_select_addr(dev, iph->saddr, + RT_SCOPE_LINK); else saddr = 0; rcu_read_unlock(); |