net: vrf: Add support for sends to local broadcast address

[ Upstream commit 1e19c4d689dc1e95bafd23ef68fbc0c6b9e05180 ]

Sukumar reported that sends to the local broadcast address
(255.255.255.255) are broken. Check for the address in vrf driver
and do not redirect to the VRF device - similar to multicast
packets.

With this change sockets can use SO_BINDTODEVICE to specify an
egress interface and receive responses. Note: the egress interface
can not be a VRF device but needs to be the enslaved device.

https://bugzilla.kernel.org/show_bug.cgi?id=198521

Reported-by: Sukumar Gopalakrishnan <sukumarg1973@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index 7dc3bcac350666396cf943fdcb583e0d97c6bf8e..67ecf2425b889ca260c84f7eb18be9f79321e29f 100644 (file)
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -674,8 +674,9 @@ static struct sk_buff *vrf_ip_out(struct net_device *vrf_dev,
                                  struct sock *sk,
                                  struct sk_buff *skb)
 {
-       /* don't divert multicast */
-       if (ipv4_is_multicast(ip_hdr(skb)->daddr))
+       /* don't divert multicast or local broadcast */
+       if (ipv4_is_multicast(ip_hdr(skb)->daddr) ||
+           ipv4_is_lbcast(ip_hdr(skb)->daddr))
                return skb;
 
        if (qdisc_tx_is_default(vrf_dev))