From b6791ac5ea49aec7f9ef123ebc728fa6a5f9090a Mon Sep 17 00:00:00 2001
From: Ido Schimmel
Date: Wed, 21 Aug 2024 15:52:50 +0300
Subject: ipv4: udp: Unmask upper DSCP bits during early demux

Unmask the upper DSCP bits when performing source validation for
multicast packets during early demux. In the future, this will allow us
to perform the FIB lookup which is performed as part of source
validation according to the full DSCP value.

No functional changes intended since the upper DSCP bits are masked when
comparing against the TOS selectors in FIB rules and routes.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240821125251.1571445-12-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 net/ipv4/udp.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'net/ipv4')

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index ddb86baaea6c..8accbf4cb295 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -115,6 +115,7 @@
 #include <net/addrconf.h>
 #include <net/udp_tunnel.h>
 #include <net/gro.h>
+#include <net/inet_dscp.h>
 #if IS_ENABLED(CONFIG_IPV6)
 #include <net/ipv6_stubs.h>
 #endif
@@ -2618,7 +2619,7 @@ int udp_v4_early_demux(struct sk_buff *skb)
 		if (!inet_sk(sk)->inet_daddr && in_dev)
 			return ip_mc_validate_source(skb, iph->daddr,
 						     iph->saddr,
-						     iph->tos & IPTOS_RT_MASK,
+						     iph->tos & INET_DSCP_MASK,
 						     skb->dev, in_dev, &itag);
 	}
 	return 0;
-- 
cgit v1.2.3