[PATCH net] udp: restore UDPlite many-cast delivery

[PATCH net] udp: restore UDPlite many-cast delivery

[Pablo Neira Ayuso]

Honor udptable parameter that is passed to __udp*_lib_mcast_deliver(),
otherwise udplite broadcast/multicast use the wrong table and it breaks.

Fixes: 2dc41cff7545 ("udp: Use hash2 for long hash1 chains in __udp*_lib_mcast_deliver.")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
It looks like UDPlite accidentally broke when dealing with long UDP many-cast
chains, give the wrong table is used for udplite. Compile tested only.

 net/ipv4/udp.c | 6 +++---
 net/ipv6/udp.c | 6 +++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 195992e0440d..5b5a552a2804 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1731,10 +1731,10 @@ static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 
 	if (use_hash2) {
 		hash2_any = udp4_portaddr_hash(net, htonl(INADDR_ANY), hnum) &
-			    udp_table.mask;
-		hash2 = udp4_portaddr_hash(net, daddr, hnum) & udp_table.mask;
+			    udptable->mask;
+		hash2 = udp4_portaddr_hash(net, daddr, hnum) & udptable->mask;
 start_lookup:
-		hslot = &udp_table.hash2[hash2];
+		hslot = &udptable->hash2[hash2];
 		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 	}
 
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index a7700bbf6788..a9dd23d5c3c4 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -688,10 +688,10 @@ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 
 	if (use_hash2) {
 		hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) &
-			    udp_table.mask;
-		hash2 = udp6_portaddr_hash(net, daddr, hnum) & udp_table.mask;
+			    udptable->mask;
+		hash2 = udp6_portaddr_hash(net, daddr, hnum) & udptable->mask;
 start_lookup:
-		hslot = &udp_table.hash2[hash2];
+		hslot = &udptable->hash2[hash2];
 		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 	}
 
-- 
2.1.4

Re: [PATCH net] udp: restore UDPlite many-cast delivery

[Eric Dumazet]

On Mon, 2016-11-14 at 23:40 +0100, Pablo Neira Ayuso wrote:
> Honor udptable parameter that is passed to __udp*_lib_mcast_deliver(),
> otherwise udplite broadcast/multicast use the wrong table and it breaks.
> 
> Fixes: 2dc41cff7545 ("udp: Use hash2 for long hash1 chains in __udp*_lib_mcast_deliver.")
> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
> ---
> It looks like UDPlite accidentally broke when dealing with long UDP many-cast
> chains, give the wrong table is used for udplite. Compile tested only.

Good catch. Looks like some people actually use UDPlite ;)

Acked-by: Eric Dumazet <edumazet@google.com>

Thanks Pablo.

Re: [PATCH net] udp: restore UDPlite many-cast delivery

[David Miller]

From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Mon, 14 Nov 2016 23:40:30 +0100

> Honor udptable parameter that is passed to __udp*_lib_mcast_deliver(),
> otherwise udplite broadcast/multicast use the wrong table and it breaks.
> 
> Fixes: 2dc41cff7545 ("udp: Use hash2 for long hash1 chains in __udp*_lib_mcast_deliver.")
> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Applied and queued up for -stable, thanks Pablo.