5.10-stable review patch. If anyone has any objections, please let me know.
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From: Antoine Tenart atenart@kernel.org
commit f2575c8f404911da83f25b688e12afcf4273e640 upstream.
Multicast packets received on an interface bound to a VRF are marked as belonging to the VRF and the skb device is updated to point to the VRF device itself. This was fine even when a route was associated to a device as when performing a fib table lookup 'oif' in fib6_table_lookup (coming from 'skb->dev->ifindex' in ip6_route_input) was set to 0 when FLOWI_FLAG_SKIP_NH_OIF was set.
With commit 40867d74c374 ("net: Add l3mdev index to flow struct and avoid oif reset for port devices") this is not longer true and multicast traffic is not received on the original interface.
Instead of adding back a similar check in fib6_table_lookup determine the dst using the original ifindex for multicast VRF traffic. To make things consistent across the function do the above for all strict packets, which was the logic before commit 6f12fa775530 ("vrf: mark skb for multicast or link-local as enslaved to VRF"). Note that reverting to this behavior should be fine as the change was about marking packets belonging to the VRF, not about their dst.
Fixes: 40867d74c374 ("net: Add l3mdev index to flow struct and avoid oif reset for port devices") Reported-by: Jianlin Shi jishi@redhat.com Signed-off-by: Antoine Tenart atenart@kernel.org Reviewed-by: David Ahern dsahern@kernel.org Link: https://lore.kernel.org/r/20221220171825.1172237-1-atenart@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/vrf.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -1336,8 +1336,8 @@ static struct sk_buff *vrf_ip6_rcv(struc
/* loopback, multicast & non-ND link-local traffic; do not push through * packet taps again. Reset pkt_type for upper layers to process skb. - * For strict packets with a source LLA, determine the dst using the - * original ifindex. + * For non-loopback strict packets, determine the dst using the original + * ifindex. */ if (skb->pkt_type == PACKET_LOOPBACK || (need_strict && !is_ndisc)) { skb->dev = vrf_dev; @@ -1346,7 +1346,7 @@ static struct sk_buff *vrf_ip6_rcv(struc
if (skb->pkt_type == PACKET_LOOPBACK) skb->pkt_type = PACKET_HOST; - else if (ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) + else vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
goto out;