net: Checks skb_dst to be NULL in inet_iif
In inet_iif check if skb_rtable is NULL for the skb and return
skb->skb_iif if it is.
This change allows inet_iif to be called before the dst
information has been set in the skb (e.g. when doing socket based
UDP GRO).
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/route.h b/include/net/route.h
index 9b0a523..f4b11ee 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -322,10 +322,11 @@
static inline int inet_iif(const struct sk_buff *skb)
{
- int iif = skb_rtable(skb)->rt_iif;
+ struct rtable *rt = skb_rtable(skb);
- if (iif)
- return iif;
+ if (rt && rt->rt_iif)
+ return rt->rt_iif;
+
return skb->skb_iif;
}