vxlan: do not use RT_TOS for IPv6 flowlabel

commit e488d4f5d6e4cd1e728ba4ddbdcd7ef5f4d13a21 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Matthias May 2022-08-05 21:19:04 +02:00 committed by Greg Kroah-Hartman
parent 13904ed832
commit 1fa0d54bd6

View 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;