From: Gao Feng <fgao@ikuai8.com>
Date: Mon, 29 Aug 2016 10:25:28 +0000 (+0800)
Subject: netfilter: log: Check param to avoid overflow in nf_log_set
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=779994fa3636d46848edb402fe7517968e036e6f;p=openwrt%2Fstaging%2Fblogic.git

netfilter: log: Check param to avoid overflow in nf_log_set

The nf_log_set is an interface function, so it should do the strict sanity
check of parameters. Convert the return value of nf_log_set as int instead
of void. When the pf is invalid, return -EOPNOTSUPP.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

diff --git a/include/net/netfilter/nf_log.h b/include/net/netfilter/nf_log.h
index 83d855ba6af1..ee07dc8b0a7b 100644
--- a/include/net/netfilter/nf_log.h
+++ b/include/net/netfilter/nf_log.h
@@ -60,8 +60,7 @@ struct nf_logger {
 int nf_log_register(u_int8_t pf, struct nf_logger *logger);
 void nf_log_unregister(struct nf_logger *logger);
 
-void nf_log_set(struct net *net, u_int8_t pf,
-		const struct nf_logger *logger);
+int nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger);
 void nf_log_unset(struct net *net, const struct nf_logger *logger);
 
 int nf_log_bind_pf(struct net *net, u_int8_t pf,
diff --git a/net/bridge/netfilter/nf_log_bridge.c b/net/bridge/netfilter/nf_log_bridge.c
index 5d9953a90929..1663df598545 100644
--- a/net/bridge/netfilter/nf_log_bridge.c
+++ b/net/bridge/netfilter/nf_log_bridge.c
@@ -50,8 +50,7 @@ static struct nf_logger nf_bridge_logger __read_mostly = {
 
 static int __net_init nf_log_bridge_net_init(struct net *net)
 {
-	nf_log_set(net, NFPROTO_BRIDGE, &nf_bridge_logger);
-	return 0;
+	return nf_log_set(net, NFPROTO_BRIDGE, &nf_bridge_logger);
 }
 
 static void __net_exit nf_log_bridge_net_exit(struct net *net)
diff --git a/net/ipv4/netfilter/nf_log_arp.c b/net/ipv4/netfilter/nf_log_arp.c
index cf8f2d4e867a..8945c2653814 100644
--- a/net/ipv4/netfilter/nf_log_arp.c
+++ b/net/ipv4/netfilter/nf_log_arp.c
@@ -111,8 +111,7 @@ static struct nf_logger nf_arp_logger __read_mostly = {
 
 static int __net_init nf_log_arp_net_init(struct net *net)
 {
-	nf_log_set(net, NFPROTO_ARP, &nf_arp_logger);
-	return 0;
+	return nf_log_set(net, NFPROTO_ARP, &nf_arp_logger);
 }
 
 static void __net_exit nf_log_arp_net_exit(struct net *net)
diff --git a/net/ipv4/netfilter/nf_log_ipv4.c b/net/ipv4/netfilter/nf_log_ipv4.c
index 076aadda0473..20f225593a8b 100644
--- a/net/ipv4/netfilter/nf_log_ipv4.c
+++ b/net/ipv4/netfilter/nf_log_ipv4.c
@@ -347,8 +347,7 @@ static struct nf_logger nf_ip_logger __read_mostly = {
 
 static int __net_init nf_log_ipv4_net_init(struct net *net)
 {
-	nf_log_set(net, NFPROTO_IPV4, &nf_ip_logger);
-	return 0;
+	return nf_log_set(net, NFPROTO_IPV4, &nf_ip_logger);
 }
 
 static void __net_exit nf_log_ipv4_net_exit(struct net *net)
diff --git a/net/ipv6/netfilter/nf_log_ipv6.c b/net/ipv6/netfilter/nf_log_ipv6.c
index 8dd869642f45..c1bcf699a23d 100644
--- a/net/ipv6/netfilter/nf_log_ipv6.c
+++ b/net/ipv6/netfilter/nf_log_ipv6.c
@@ -379,8 +379,7 @@ static struct nf_logger nf_ip6_logger __read_mostly = {
 
 static int __net_init nf_log_ipv6_net_init(struct net *net)
 {
-	nf_log_set(net, NFPROTO_IPV6, &nf_ip6_logger);
-	return 0;
+	return nf_log_set(net, NFPROTO_IPV6, &nf_ip6_logger);
 }
 
 static void __net_exit nf_log_ipv6_net_exit(struct net *net)
diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index aa5847a16713..30a17d649a83 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -39,12 +39,12 @@ static struct nf_logger *__find_logger(int pf, const char *str_logger)
 	return NULL;
 }
 
-void nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger)
+int nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger)
 {
 	const struct nf_logger *log;
 
-	if (pf == NFPROTO_UNSPEC)
-		return;
+	if (pf == NFPROTO_UNSPEC || pf >= ARRAY_SIZE(net->nf.nf_loggers))
+		return -EOPNOTSUPP;
 
 	mutex_lock(&nf_log_mutex);
 	log = nft_log_dereference(net->nf.nf_loggers[pf]);
@@ -52,6 +52,8 @@ void nf_log_set(struct net *net, u_int8_t pf, const struct nf_logger *logger)
 		rcu_assign_pointer(net->nf.nf_loggers[pf], logger);
 
 	mutex_unlock(&nf_log_mutex);
+
+	return 0;
 }
 EXPORT_SYMBOL(nf_log_set);