@@ -457,6 +457,23 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
local_bh_enable();
}
+/*
+ * The device used for looking up which routing table to use for sending an ICMP
+ * error is preferably the source whenever it is set, which should ensure the
+ * icmp error can be sent to the source host, else lookup using the routing
+ * table of the destination device, else use the main routing table (index 0).
+ */
+static struct net_device *icmp_get_route_lookup_dev(struct sk_buff *skb)
+{
+ struct net_device *route_lookup_dev = NULL;
+
+ if (skb->dev)
+ route_lookup_dev = skb->dev;
+ else if (skb_dst(skb))
+ route_lookup_dev = skb_dst(skb)->dev;
+ return route_lookup_dev;
+}
+
static struct rtable *icmp_route_lookup(struct net *net,
struct flowi4 *fl4,
struct sk_buff *skb_in,
@@ -465,6 +482,7 @@ static struct rtable *icmp_route_lookup(struct net *net,
int type, int code,
struct icmp_bxm *param)
{
+ struct net_device *route_lookup_dev;
struct rtable *rt, *rt2;
struct flowi4 fl4_dec;
int err;
@@ -479,7 +497,8 @@ 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_dst(skb_in)->dev);
+ route_lookup_dev = icmp_get_route_lookup_dev(skb_in);
+ fl4->flowi4_oif = l3mdev_master_ifindex(route_lookup_dev);
security_skb_classify_flow(skb_in, flowi4_to_flowi(fl4));
rt = ip_route_output_key_hash(net, fl4, skb_in);
@@ -503,7 +522,7 @@ static struct rtable *icmp_route_lookup(struct net *net,
if (err)
goto relookup_failed;
- if (inet_addr_type_dev_table(net, skb_dst(skb_in)->dev,
+ if (inet_addr_type_dev_table(net, route_lookup_dev,
fl4_dec.saddr) == RTN_LOCAL) {
rt2 = __ip_route_output_key(net, &fl4_dec);
if (IS_ERR(rt2))