Currently, ingress ipv4 broadcast datagrams are dropped since,
in udp_v4_early_demux(), ip_check_mc_rcu() is invoked even on
bcast packets.
This patch addresses the issue, invoking ip_check_mc_rcu()
only for mcast packets.
Fixes: 6e5403093261 ("ipv4/udp: Verify multicast group is ours in
upd_v4_early_demux()")
Signed-off-by: Paolo Abeni <[email protected]>
--
v1 -> v2 droped the route related bits, the fib_validate_source()
failures are triggered by the in_device configuration
---
net/ipv4/udp.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 836abe5..08eed5e 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -2070,10 +2070,14 @@ void udp_v4_early_demux(struct sk_buff *skb)
if (!in_dev)
return;
- ours = ip_check_mc_rcu(in_dev, iph->daddr, iph->saddr,
- iph->protocol);
- if (!ours)
- return;
+ /* we are supposed to accept bcast packets */
+ if (skb->pkt_type == PACKET_MULTICAST) {
+ ours = ip_check_mc_rcu(in_dev, iph->daddr, iph->saddr,
+ iph->protocol);
+ if (!ours)
+ return;
+ }
+
sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr,
uh->source, iph->saddr, dif);
} else if (skb->pkt_type == PACKET_HOST) {
--
1.8.3.1
