[PATCH v2] net: icmp_route_lookup should use rt dev to determine L3 domain

[David Ahern]

icmp_send is called in response to some event. The skb may not have
the device set (skb->dev is NULL), but it is expected to have an rt.
Update icmp_route_lookup to use the rt on the skb to determine L3
domain.

Fixes: 613d09b30f8b ("net: Use VRF device index for lookups on TX")
Signed-off-by: David Ahern <d...@cumulusnetworks.com>
---
v2
- use skb_dst versus skb_rtable

 net/ipv4/icmp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 53a890b605fc..691146abde2d 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -479,7 +479,7 @@ static struct rtable *icmp_route_lookup(struct net *net,
        fl4->flowi4_proto = IPPROTO_ICMP;
        fl4->fl4_icmp_type = type;
        fl4->fl4_icmp_code = code;
-       fl4->flowi4_oif = l3mdev_master_ifindex(skb_in->dev);
+       fl4->flowi4_oif = l3mdev_master_ifindex(skb_dst(skb_in)->dev);
 
        security_skb_classify_flow(skb_in, flowi4_to_flowi(fl4));
        rt = __ip_route_output_key_hash(net, fl4,
@@ -504,7 +504,7 @@ static struct rtable *icmp_route_lookup(struct net *net,
        if (err)
                goto relookup_failed;
 
-       if (inet_addr_type_dev_table(net, skb_in->dev,
+       if (inet_addr_type_dev_table(net, skb_dst(skb_in)->dev,
                                     fl4_dec.saddr) == RTN_LOCAL) {
                rt2 = __ip_route_output_key(net, &fl4_dec);
                if (IS_ERR(rt2))
-- 
2.1.4