From: Guillaume Nault gnault@redhat.com
commit e010ae08c71fda8be3d6bda256837795a0b3ea41 upstream.
Take into account the IPV6_TCLASS socket option (DSCP) in ip6_datagram_flow_key_init(). Otherwise fib6_rule_match() can't properly match the DSCP value, resulting in invalid route lookup.
For example:
ip route add unreachable table main 2001:db8::10/124
ip route add table 100 2001:db8::10/124 dev eth0 ip -6 rule add dsfield 0x04 table 100
echo test | socat - UDP6:[2001:db8::11]:54321,ipv6-tclass=0x04
Without this patch, socat fails at connect() time ("No route to host") because the fib-rule doesn't jump to table 100 and the lookup ends up being done in the main table.
Fixes: 2cc67cc731d9 ("[IPV6] ROUTE: Routing by Traffic Class.") Signed-off-by: Guillaume Nault gnault@redhat.com Reviewed-by: Eric Dumazet edumazet@google.com Reviewed-by: David Ahern dsahern@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv6/datagram.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -50,7 +50,7 @@ static void ip6_datagram_flow_key_init(s fl6->flowi6_mark = sk->sk_mark; fl6->fl6_dport = inet->inet_dport; fl6->fl6_sport = inet->inet_sport; - fl6->flowlabel = np->flow_label; + fl6->flowlabel = ip6_make_flowinfo(np->tclass, np->flow_label); fl6->flowi6_uid = sk->sk_uid;
if (!fl6->flowi6_oif)