[PATCH 3/6] netfilter: ipset: Fix wraparound in hash:net types

From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: 2018-02-01 18:02:14
Also in: netfilter-devel
Subsystem: netfilter, networking [general], the rest · Maintainers: Pablo Neira Ayuso, Florian Westphal, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds

From: Jozsef Kadlecsik <redacted>

Fix wraparound bug which could lead to memory exhaustion when adding an
x.x.x.x-255.255.255.255 range to any hash:*net* types.

Fixes Netfilter's bugzilla id #1212, reported by Thomas Schwark.

Fixes: 48596a8ddc46 ("netfilter: ipset: Fix adding an IPv4 range containing more than 2^31 addresses")
Signed-off-by: Jozsef Kadlecsik <redacted>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/ipset/ip_set_hash_ipportnet.c  | 26 ++++++++++-----------
 net/netfilter/ipset/ip_set_hash_net.c        |  9 ++++---
 net/netfilter/ipset/ip_set_hash_netiface.c   |  9 ++++---
 net/netfilter/ipset/ip_set_hash_netnet.c     | 28 +++++++++++-----------
 net/netfilter/ipset/ip_set_hash_netport.c    | 19 ++++++++-------
 net/netfilter/ipset/ip_set_hash_netportnet.c | 35 ++++++++++++++--------------
 6 files changed, 63 insertions(+), 63 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_hash_ipportnet.c b/net/netfilter/ipset/ip_set_hash_ipportnet.c
index 0f164e986bf1..88b83d6d3084 100644
--- a/net/netfilter/ipset/ip_set_hash_ipportnet.c
+++ b/net/netfilter/ipset/ip_set_hash_ipportnet.c

@@ -168,7 +168,7 @@ hash_ipportnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 	struct hash_ipportnet4_elem e = { .cidr = HOST_MASK - 1 };
 	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_last, ip2;
+	u32 ip2_from = 0, ip2_to = 0, ip2;
 	bool with_ports = false;
 	u8 cidr;
 	int ret;

@@ -269,22 +269,21 @@ hash_ipportnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 		ip_set_mask_from_to(ip2_from, ip2_to, e.cidr + 1);
 	}
 
-	if (retried)
+	if (retried) {
 		ip = ntohl(h->next.ip);
+		p = ntohs(h->next.port);
+		ip2 = ntohl(h->next.ip2);
+	} else {
+		p = port;
+		ip2 = ip2_from;
+	}
 	for (; ip <= ip_to; ip++) {
 		e.ip = htonl(ip);
-		p = retried && ip == ntohl(h->next.ip) ? ntohs(h->next.port)
-						       : port;
 		for (; p <= port_to; p++) {
 			e.port = htons(p);
-			ip2 = retried &&
-			      ip == ntohl(h->next.ip) &&
-			      p == ntohs(h->next.port)
-				? ntohl(h->next.ip2) : ip2_from;
-			while (ip2 <= ip2_to) {
+			do {
 				e.ip2 = htonl(ip2);
-				ip2_last = ip_set_range_to_cidr(ip2, ip2_to,
-								&cidr);
+				ip2 = ip_set_range_to_cidr(ip2, ip2_to, &cidr);
 				e.cidr = cidr - 1;
 				ret = adtfn(set, &e, &ext, &ext, flags);

@@ -292,9 +291,10 @@ hash_ipportnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 					return ret;
 
 				ret = 0;
-				ip2 = ip2_last + 1;
-			}
+			} while (ip2++ < ip2_to);
+			ip2 = ip2_from;
 		}
+		p = port;
 	}
 	return ret;
 }

diff --git a/net/netfilter/ipset/ip_set_hash_net.c b/net/netfilter/ipset/ip_set_hash_net.c
index 1c67a1761e45..5449e23af13a 100644
--- a/net/netfilter/ipset/ip_set_hash_net.c
+++ b/net/netfilter/ipset/ip_set_hash_net.c

@@ -143,7 +143,7 @@ hash_net4_uadt(struct ip_set *set, struct nlattr *tb[],
 	ipset_adtfn adtfn = set->variant->adt[adt];
 	struct hash_net4_elem e = { .cidr = HOST_MASK };
 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
-	u32 ip = 0, ip_to = 0, last;
+	u32 ip = 0, ip_to = 0;
 	int ret;
 
 	if (tb[IPSET_ATTR_LINENO])

@@ -193,16 +193,15 @@ hash_net4_uadt(struct ip_set *set, struct nlattr *tb[],
 	}
 	if (retried)
 		ip = ntohl(h->next.ip);
-	while (ip <= ip_to) {
+	do {
 		e.ip = htonl(ip);
-		last = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
+		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
 		ret = adtfn(set, &e, &ext, &ext, flags);
 		if (ret && !ip_set_eexist(ret, flags))
 			return ret;
 
 		ret = 0;
-		ip = last + 1;
-	}
+	} while (ip++ < ip_to);
 	return ret;
 }

diff --git a/net/netfilter/ipset/ip_set_hash_netiface.c b/net/netfilter/ipset/ip_set_hash_netiface.c
index d417074f1c1a..f5164c1efce2 100644
--- a/net/netfilter/ipset/ip_set_hash_netiface.c
+++ b/net/netfilter/ipset/ip_set_hash_netiface.c

@@ -200,7 +200,7 @@ hash_netiface4_uadt(struct ip_set *set, struct nlattr *tb[],
 	ipset_adtfn adtfn = set->variant->adt[adt];
 	struct hash_netiface4_elem e = { .cidr = HOST_MASK, .elem = 1 };
 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
-	u32 ip = 0, ip_to = 0, last;
+	u32 ip = 0, ip_to = 0;
 	int ret;
 
 	if (tb[IPSET_ATTR_LINENO])

@@ -255,17 +255,16 @@ hash_netiface4_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	if (retried)
 		ip = ntohl(h->next.ip);
-	while (ip <= ip_to) {
+	do {
 		e.ip = htonl(ip);
-		last = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
+		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
 		ret = adtfn(set, &e, &ext, &ext, flags);
 
 		if (ret && !ip_set_eexist(ret, flags))
 			return ret;
 
 		ret = 0;
-		ip = last + 1;
-	}
+	} while (ip++ < ip_to);
 	return ret;
 }

diff --git a/net/netfilter/ipset/ip_set_hash_netnet.c b/net/netfilter/ipset/ip_set_hash_netnet.c
index 7f9ae2e9645b..5a2b923bd81f 100644
--- a/net/netfilter/ipset/ip_set_hash_netnet.c
+++ b/net/netfilter/ipset/ip_set_hash_netnet.c

@@ -169,8 +169,8 @@ hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 	ipset_adtfn adtfn = set->variant->adt[adt];
 	struct hash_netnet4_elem e = { };
 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
-	u32 ip = 0, ip_to = 0, last;
-	u32 ip2 = 0, ip2_from = 0, ip2_to = 0, last2;
+	u32 ip = 0, ip_to = 0;
+	u32 ip2 = 0, ip2_from = 0, ip2_to = 0;
 	int ret;
 
 	if (tb[IPSET_ATTR_LINENO])

@@ -247,27 +247,27 @@ hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 		ip_set_mask_from_to(ip2_from, ip2_to, e.cidr[1]);
 	}
 
-	if (retried)
+	if (retried) {
 		ip = ntohl(h->next.ip[0]);
+		ip2 = ntohl(h->next.ip[1]);
+	} else {
+		ip2 = ip2_from;
+	}
 
-	while (ip <= ip_to) {
+	do {
 		e.ip[0] = htonl(ip);
-		last = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
-		ip2 = (retried &&
-		       ip == ntohl(h->next.ip[0])) ? ntohl(h->next.ip[1])
-						   : ip2_from;
-		while (ip2 <= ip2_to) {
+		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
+		do {
 			e.ip[1] = htonl(ip2);
-			last2 = ip_set_range_to_cidr(ip2, ip2_to, &e.cidr[1]);
+			ip2 = ip_set_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;
 
 			ret = 0;
-			ip2 = last2 + 1;
-		}
-		ip = last + 1;
-	}
+		} while (ip2++ < ip2_to);
+		ip2 = ip2_from;
+	} while (ip++ < ip_to);
 	return ret;
 }

diff --git a/net/netfilter/ipset/ip_set_hash_netport.c b/net/netfilter/ipset/ip_set_hash_netport.c
index e6ef382febe4..1a187be9ebc8 100644
--- a/net/netfilter/ipset/ip_set_hash_netport.c
+++ b/net/netfilter/ipset/ip_set_hash_netport.c

@@ -161,7 +161,7 @@ hash_netport4_uadt(struct ip_set *set, struct nlattr *tb[],
 	ipset_adtfn adtfn = set->variant->adt[adt];
 	struct hash_netport4_elem e = { .cidr = HOST_MASK - 1 };
 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
-	u32 port, port_to, p = 0, ip = 0, ip_to = 0, last;
+	u32 port, port_to, p = 0, ip = 0, ip_to = 0;
 	bool with_ports = false;
 	u8 cidr;
 	int ret;

@@ -239,25 +239,26 @@ hash_netport4_uadt(struct ip_set *set, struct nlattr *tb[],
 		ip_set_mask_from_to(ip, ip_to, e.cidr + 1);
 	}
 
-	if (retried)
+	if (retried) {
 		ip = ntohl(h->next.ip);
-	while (ip <= ip_to) {
+		p = ntohs(h->next.port);
+	} else {
+		p = port;
+	}
+	do {
 		e.ip = htonl(ip);
-		last = ip_set_range_to_cidr(ip, ip_to, &cidr);
+		ip = ip_set_range_to_cidr(ip, ip_to, &cidr);
 		e.cidr = cidr - 1;
-		p = retried && ip == ntohl(h->next.ip) ? ntohs(h->next.port)
-						       : port;
 		for (; p <= port_to; p++) {
 			e.port = htons(p);
 			ret = adtfn(set, &e, &ext, &ext, flags);
-
 			if (ret && !ip_set_eexist(ret, flags))
 				return ret;
 
 			ret = 0;
 		}
-		ip = last + 1;
-	}
+		p = port;
+	} while (ip++ < ip_to);
 	return ret;
 }

diff --git a/net/netfilter/ipset/ip_set_hash_netportnet.c b/net/netfilter/ipset/ip_set_hash_netportnet.c
index 8602f2595a1a..d391485a6acd 100644
--- a/net/netfilter/ipset/ip_set_hash_netportnet.c
+++ b/net/netfilter/ipset/ip_set_hash_netportnet.c

@@ -184,8 +184,8 @@ hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 	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, ip_last, p = 0, port, port_to;
-	u32 ip2_from = 0, ip2_to = 0, ip2_last, ip2;
+	u32 ip = 0, ip_to = 0, p = 0, port, port_to;
+	u32 ip2_from = 0, ip2_to = 0, ip2;
 	bool with_ports = false;
 	int ret;

@@ -288,33 +288,34 @@ hash_netportnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 		ip_set_mask_from_to(ip2_from, ip2_to, e.cidr[1]);
 	}
 
-	if (retried)
+	if (retried) {
 		ip = ntohl(h->next.ip[0]);
+		p = ntohs(h->next.port);
+		ip2 = ntohl(h->next.ip[1]);
+	} else {
+		p = port;
+		ip2 = ip2_from;
+	}
 
-	while (ip <= ip_to) {
+	do {
 		e.ip[0] = htonl(ip);
-		ip_last = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
-		p = retried && ip == ntohl(h->next.ip[0]) ? ntohs(h->next.port)
-							  : port;
+		ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
 		for (; p <= port_to; p++) {
 			e.port = htons(p);
-			ip2 = (retried && ip == ntohl(h->next.ip[0]) &&
-			       p == ntohs(h->next.port)) ? ntohl(h->next.ip[1])
-							 : ip2_from;
-			while (ip2 <= ip2_to) {
+			do {
 				e.ip[1] = htonl(ip2);
-				ip2_last = ip_set_range_to_cidr(ip2, ip2_to,
-								&e.cidr[1]);
+				ip2 = ip_set_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;
 
 				ret = 0;
-				ip2 = ip2_last + 1;
-			}
+			} while (ip2++ < ip2_to);
+			ip2 = ip2_from;
 		}
-		ip = ip_last + 1;
-	}
+		p = port;
+	} while (ip++ < ip_to);
 	return ret;
 }

-- 
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