[PATCH net-next 4/7] ipv4: Convert ip_route_input_mc() to dscp_t.

[Guillaume Nault <gnault@redhat.com>]

Pass a dscp_t variable to ip_route_input_mc(), instead of a plain u8,
to prevent accidental setting of ECN bits in ->flowi4_tos.

Only ip_route_input_rcu() actually calls ip_route_input_mc(). Since it
already has a dscp_t variable to pass as parameter, we only need to
remove the inet_dscp_to_dsfield() conversion.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
---
 net/ipv4/route.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 763b8bafd1bf..527121be1ba2 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1697,7 +1697,7 @@ int ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 
 /* called in rcu_read_lock() section */
 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
-			     u8 tos, struct net_device *dev, int our)
+			     dscp_t dscp, struct net_device *dev, int our)
 {
 	struct in_device *in_dev = __in_dev_get_rcu(dev);
 	unsigned int flags = RTCF_MULTICAST;
@@ -1705,7 +1705,9 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	u32 itag = 0;
 	int err;
 
-	err = ip_mc_validate_source(skb, daddr, saddr, tos, dev, in_dev, &itag);
+	err = ip_mc_validate_source(skb, daddr, saddr,
+				    inet_dscp_to_dsfield(dscp), dev, in_dev,
+				    &itag);
 	if (err)
 		return err;
 
@@ -2455,9 +2457,8 @@ static int ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 		     IN_DEV_MFORWARD(in_dev))
 #endif
 		   ) {
-			err = ip_route_input_mc(skb, daddr, saddr,
-						inet_dscp_to_dsfield(dscp),
-						dev, our);
+			err = ip_route_input_mc(skb, daddr, saddr, dscp, dev,
+						our);
 		}
 		return err;
 	}
-- 
2.39.2