netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_…

…set_hash_netportnet.c

The missing IP_SET_HASH_WITH_NET0 macro in ip_set_hash_netportnet can
lead to the use of wrong `CIDR_POS(c)` for calculating array offsets,
which can lead to integer underflow. As a result, it leads to slab
out-of-bound access.
This patch adds back the IP_SET_HASH_WITH_NET0 macro to
ip_set_hash_netportnet to address the issue.

Fixes: 886503f ("netfilter: ipset: actually allow allowable CIDR 0 in hash:net,port,net")
Suggested-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Kyle Zeng <zengyhkyle@gmail.com>
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>

net/netfilter/ipset/ip_set_hash_netportnet.c

@@ -36,6 +36,7 @@ MODULE_ALIAS("ip_set_hash:net,port,net");
 #define IP_SET_HASH_WITH_PROTO
 #define IP_SET_HASH_WITH_NETS
 #define IPSET_NET_COUNT 2
+#define IP_SET_HASH_WITH_NET0
 
 /* IPv4 variant */