vxlan: do not use RT_TOS for IPv6 flowlabel
authorMatthias May <matthias.may@westermo.com>
Fri, 5 Aug 2022 19:19:04 +0000 (21:19 +0200)
committerJakub Kicinski <kuba@kernel.org>
Wed, 10 Aug 2022 05:19:20 +0000 (22:19 -0700)
According to Guillaume Nault RT_TOS should never be used for IPv6.

Quote:
RT_TOS() is an old macro used to interprete IPv4 TOS as described in
the obsolete RFC 1349. It's conceptually wrong to use it even in IPv4
code, although, given the current state of the code, most of the
existing calls have no consequence.

But using RT_TOS() in IPv6 code is always a bug: IPv6 never had a "TOS"
field to be interpreted the RFC 1349 way. There's no historical
compatibility to worry about.

Fixes: 1400615d64cf ("vxlan: allow setting ipv6 traffic class")
Acked-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Matthias May <matthias.may@westermo.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
drivers/net/vxlan/vxlan_core.c

index 90811ab851fd8bddead016764d05e01d60a76054..c3285242f74fbdb9efe03712fe680f24faefecb3 100644 (file)
@@ -2321,7 +2321,7 @@ static struct dst_entry *vxlan6_get_route(struct vxlan_dev *vxlan,
        fl6.flowi6_oif = oif;
        fl6.daddr = *daddr;
        fl6.saddr = *saddr;
-       fl6.flowlabel = ip6_make_flowinfo(RT_TOS(tos), label);
+       fl6.flowlabel = ip6_make_flowinfo(tos, label);
        fl6.flowi6_mark = skb->mark;
        fl6.flowi6_proto = IPPROTO_UDP;
        fl6.fl6_dport = dport;