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From:   Matthias May <matthias.may@westermo.com>
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Subject: [PATCH v3 net 2/4] vxlan: do not use RT_TOS for IPv6 flowlabel
Date:   Fri, 5 Aug 2022 21:19:04 +0200
Message-ID: <20220805191906.9323-3-matthias.may@westermo.com>
In-Reply-To: <20220805191906.9323-1-matthias.may@westermo.com>
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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>
---
v1 -> v2:
 - Fix spacing of "Fixes" tag.
 - Add missing CCs
v2 -> v3:
 - Add the info from the cover to the actual patch message (Guillaume Nault)
---
 drivers/net/vxlan/vxlan_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index 265d4a0245e7..797585fbb004 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -2320,7 +2320,7 @@ 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;
-- 
2.35.1