ipv6: omit traffic class when calculating flow hash
authorMichal Kubecek <mkubecek@suse.cz>
Sat, 2 Jun 2018 07:40:34 +0000 (09:40 +0200)
committerDavid S. Miller <davem@davemloft.net>
Mon, 4 Jun 2018 17:18:35 +0000 (13:18 -0400)
commit87ae68c8b4944d142447b88875c9c412c714434f
treeed27f4796483c56b128a7c2f40d0b59540ffc6fe
parentfe083b3f06e91cf8508f23922867e52348205825
ipv6: omit traffic class when calculating flow hash

Some of the code paths calculating flow hash for IPv6 use flowlabel member
of struct flowi6 which, despite its name, encodes both flow label and
traffic class. If traffic class changes within a TCP connection (as e.g.
ssh does), ECMP route can switch between path. It's also incosistent with
other code paths where ip6_flowlabel() (returning only flow label) is used
to feed the key.

Use only flow label everywhere, including one place where hash key is set
using ip6_flowinfo().

Fixes: 51ebd3181572 ("ipv6: add support of equal cost multipath (ECMP)")
Fixes: f70ea018da06 ("net: Add functions to get skb->hash based on flow structures")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/ipv6.h
net/core/flow_dissector.c
net/ipv6/route.c