From 8a6f0ec69115ba417c5ad06047040240991520ce Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik Date: Thu, 29 Dec 2022 15:00:21 +0100 Subject: netfilter: ipset: fix hash:net,port,net hang with /0 subnet MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The hash:net,port,net set type supports /0 subnets. However, the patch commit 5f7b51bf09baca8e titled "netfilter: ipset: Limit the maximal range of consecutive elements to add/delete" did not take into account it and resulted in an endless loop. The bug is actually older but the patch 5f7b51bf09baca8e brings it out earlier. Handle /0 subnets properly in hash:net,port,net set types. Reported-by: Марк Коренберг Signed-off-by: Jozsef Kadlecsik --- .../net/netfilter/ipset/ip_set_hash_netportnet.c | 40 ++++++++++++---------- 1 file changed, 21 insertions(+), 19 deletions(-) (limited to 'kernel') diff --git a/kernel/net/netfilter/ipset/ip_set_hash_netportnet.c b/kernel/net/netfilter/ipset/ip_set_hash_netportnet.c index 57be102..fd080ab 100644 --- a/kernel/net/netfilter/ipset/ip_set_hash_netportnet.c +++ b/kernel/net/netfilter/ipset/ip_set_hash_netportnet.c @@ -174,17 +174,26 @@ hash_netportnet4_kadt(struct ip_set *set, const struct sk_buff *skb, return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags); } +static u32 +hash_netportnet4_range_to_cidr(u32 from, u32 to, u8 *cidr) +{ + if (from == 0 && to == UINT_MAX) { + *cidr = 0; + return to; + } + return ip_set_range_to_cidr(from, to, cidr); +} + static int hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[], enum ipset_adt adt, u32 *lineno, u32 flags, bool retried) { - const struct hash_netportnet4 *h = set->data; + struct hash_netportnet4 *h = set->data; ipset_adtfn adtfn = set->variant->adt[adt]; struct hash_netportnet4_elem e = { }; struct ip_set_ext ext = IP_SET_INIT_UEXT(set); u32 ip = 0, ip_to = 0, p = 0, port, port_to; - u32 ip2_from = 0, ip2_to = 0, ip2, ipn; - u64 n = 0, m = 0; + u32 ip2_from = 0, ip2_to = 0, ip2, i = 0; bool with_ports = false; int ret; @@ -286,19 +295,6 @@ hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[], } else { ip_set_mask_from_to(ip2_from, ip2_to, e.cidr[1]); } - ipn = ip; - do { - ipn = ip_set_range_to_cidr(ipn, ip_to, &e.cidr[0]); - n++; - } while (ipn++ < ip_to); - ipn = ip2_from; - do { - ipn = ip_set_range_to_cidr(ipn, ip2_to, &e.cidr[1]); - m++; - } while (ipn++ < ip2_to); - - if (n*m*(port_to - port + 1) > IPSET_MAX_RANGE) - return -ERANGE; if (retried) { ip = ntohl(h->next.ip[0]); @@ -311,13 +307,19 @@ hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[], do { e.ip[0] = htonl(ip); - ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]); + ip = hash_netportnet4_range_to_cidr(ip, ip_to, &e.cidr[0]); for (; p <= port_to; p++) { e.port = htons(p); do { + i++; e.ip[1] = htonl(ip2); - ip2 = ip_set_range_to_cidr(ip2, ip2_to, - &e.cidr[1]); + if (i > IPSET_MAX_RANGE) { + hash_netportnet4_data_next(&h->next, + &e); + return -ERANGE; + } + ip2 = hash_netportnet4_range_to_cidr(ip2, + ip2_to, &e.cidr[1]); ret = adtfn(set, &e, &ext, &ext, flags); if (ret && !ip_set_eexist(ret, flags)) return ret; -- cgit v1.2.3