ipv6: add flowinfo for tcp6 pkt_options for all cases

The current implementation of IPV6_FLOWINFO only gives a
result if pktoptions is available (thanks to the
ip6_datagram_recv_ctl function).
It gives inconsistent results to user space, sometimes
there is a result for getsockopt(IPV6_FLOWINFO), sometimes
not.

This patch add rcv_flowinfo to store it, and return it to
the userspace in the same way than other pkt_options.

Signed-off-by: Florent Fourcot <florent.fourcot@enst-bretagne.fr>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 1c6ce31..c2db1df 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -1034,6 +1034,10 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
 				int hlim = np->mcast_hops;
 				put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 			}
+			if (np->rxopt.bits.rxflow) {
+				int flowinfo = np->rcv_flowinfo;
+				put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
+			}
 		}
 		len -= msg.msg_controllen;
 		return put_user(len, optlen);