Commit 0b922b7a authored by David Ahern's avatar David Ahern Committed by David S. Miller

net: original ingress device index in PKTINFO

Applications such as OSPF and BFD need the original ingress device not
the VRF device; the latter can be derived from the former. To that end
add the skb_iif to inet_skb_parm and set it in ipv4 code after clearing
the skb control buffer similar to IPv6. From there the pktinfo can just
pull it from cb with the PKTINFO_SKB_CB cast.

The previous patch moving the skb->dev change to L3 means nothing else
is needed for IPv6; it just works.
Signed-off-by: default avatarDavid Ahern <>
Signed-off-by: default avatarDavid S. Miller <>
parent 74b20582
......@@ -36,6 +36,7 @@
struct sock;
struct inet_skb_parm {
int iif;
struct ip_options opt; /* Compiled IP options */
unsigned char flags;
......@@ -478,6 +478,7 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
/* Remove any debris in the socket control block */
memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
IPCB(skb)->iif = skb->skb_iif;
/* Must drop socket now because of tproxy. */
......@@ -1193,7 +1193,12 @@ void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb)
if (prepare && skb_rtable(skb)) {
pktinfo->ipi_ifindex = inet_iif(skb);
/* skb->cb is overloaded: prior to this point it is IP{6}CB
* which has interface index (iif) as the first member of the
* underlying inet{6}_skb_parm struct. This code then overlays
* PKTINFO_SKB_CB and in_pktinfo also has iif as the first
* element so the iif is picked up from the prior IPCB
pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
} else {
pktinfo->ipi_ifindex = 0;
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment