Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

The new route handling in ip_mc_finish_output() from 'net' overlapped
with the new support for returning congestion notifications from BPF
programs.

In order to handle this I had to take the dev_loopback_xmit() calls
out of the switch statement.

The aquantia driver conflicts were simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 4 deletions

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index cdd6c3418b9e..cc7ef0d05bbd 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -327,18 +327,35 @@ static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *sk
 static int ip_mc_finish_output(struct net *net, struct sock *sk,
 			       struct sk_buff *skb)
 {
-	int ret;
+	struct rtable *new_rt;
+	bool do_cn = false;
+	int ret, err;
 
 	ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb);
 	switch (ret) {
-	case NET_XMIT_SUCCESS:
-		return dev_loopback_xmit(net, sk, skb);
 	case NET_XMIT_CN:
-		return dev_loopback_xmit(net, sk, skb) ? : ret;
+		do_cn = true;
+		/* fall through */
+	case NET_XMIT_SUCCESS:
+		break;
 	default:
 		kfree_skb(skb);
 		return ret;
 	}
+
+	/* Reset rt_iif so that inet_iif() will return skb->skb_iif. Setting
+	 * this to non-zero causes ipi_ifindex in in_pktinfo to be overwritten,
+	 * see ipv4_pktinfo_prepare().
+	 */
+	new_rt = rt_dst_clone(net->loopback_dev, skb_rtable(skb));
+	if (new_rt) {
+		new_rt->rt_iif = 0;
+		skb_dst_drop(skb);
+		skb_dst_set(skb, &new_rt->dst);
+	}
+
+	err = dev_loopback_xmit(net, sk, skb);
+	return (do_cn && err) ? ret : err;
 }
 
 int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb)