geneve: do not use RT_TOS for IPv6 flowlabel

commit 99470e99d939716d39428acad37308fd5169a300 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: 3c9229807100 ("geneve: handle ipv6 priority like ipv4 tos")
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>

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 84f5717c01e2a1e175f5c5d01a6c373f641095b8..5636673b84e7db33566e67389449869c77cbac19 100644 (file)
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -851,8 +851,7 @@ static struct dst_entry *geneve_get_v6_dst(struct sk_buff *skb,
                use_cache = false;
        }
 
-       fl6->flowlabel = ip6_make_flowinfo(RT_TOS(prio),
-                                          info->key.label);
+       fl6->flowlabel = ip6_make_flowinfo(prio, info->key.label);
        dst_cache = (struct dst_cache *)&info->dst_cache;
        if (use_cache) {
                dst = dst_cache_get_ip6(dst_cache, &fl6->saddr);