[PATCH AUTOSEL 4.18 06/59] netfilter: ipset: actually allow allowable CIDR 0 in hash:net,port,net

From: Sasha Levin
Date: Wed Nov 14 2018 - 17:23:59 EST


From: Eric Westbrook <eric@xxxxxxxxxxxx>

[ Upstream commit 886503f34d63e681662057448819edb5b1057a97 ]

Allow /0 as advertised for hash:net,port,net sets.

For "hash:net,port,net", ipset(8) says that "either subnet
is permitted to be a /0 should you wish to match port
between all destinations."

Make that statement true.

Before:

# ipset create cidrzero hash:net,port,net
# ipset add cidrzero 0.0.0.0/0,12345,0.0.0.0/0
ipset v6.34: The value of the CIDR parameter of the IP address is invalid

# ipset create cidrzero6 hash:net,port,net family inet6
# ipset add cidrzero6 ::/0,12345,::/0
ipset v6.34: The value of the CIDR parameter of the IP address is invalid

After:

# ipset create cidrzero hash:net,port,net
# ipset add cidrzero 0.0.0.0/0,12345,0.0.0.0/0
# ipset test cidrzero 192.168.205.129,12345,172.16.205.129
192.168.205.129,tcp:12345,172.16.205.129 is in set cidrzero.

# ipset create cidrzero6 hash:net,port,net family inet6
# ipset add cidrzero6 ::/0,12345,::/0
# ipset test cidrzero6 fe80::1,12345,ff00::1
fe80::1,tcp:12345,ff00::1 is in set cidrzero6.

See also:

https://bugzilla.kernel.org/show_bug.cgi?id=200897
https://github.com/ewestbrook/linux/commit/df7ff6efb0934ab6acc11f003ff1a7580d6c1d9c

Signed-off-by: Eric Westbrook <linux@xxxxxxxxxxxx>
Signed-off-by: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/netfilter/ipset/ip_set_hash_netportnet.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_hash_netportnet.c b/net/netfilter/ipset/ip_set_hash_netportnet.c
index d391485a6acd..613e18e720a4 100644
--- a/net/netfilter/ipset/ip_set_hash_netportnet.c
+++ b/net/netfilter/ipset/ip_set_hash_netportnet.c
@@ -213,13 +213,13 @@ hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[],

if (tb[IPSET_ATTR_CIDR]) {
e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
- if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
+ if (e.cidr[0] > HOST_MASK)
return -IPSET_ERR_INVALID_CIDR;
}

if (tb[IPSET_ATTR_CIDR2]) {
e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
- if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
+ if (e.cidr[1] > HOST_MASK)
return -IPSET_ERR_INVALID_CIDR;
}

@@ -493,13 +493,13 @@ hash_netportnet6_uadt(struct ip_set *set, struct nlattr *tb[],

if (tb[IPSET_ATTR_CIDR]) {
e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
- if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
+ if (e.cidr[0] > HOST_MASK)
return -IPSET_ERR_INVALID_CIDR;
}

if (tb[IPSET_ATTR_CIDR2]) {
e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
- if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
+ if (e.cidr[1] > HOST_MASK)
return -IPSET_ERR_INVALID_CIDR;
}

--
2.17.1