Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net, they are: 1) Unaligned atomic access in ipset, from Russell King. 2) Missing module description, from Rob Gill. 3) Patches to fix a module unload causing NULL pointer dereference in xtables, from David Wilder. For the record, I posting here his cover letter explaining the problem: A crash happened on ppc64le when running ltp network tests triggered by "rmmod iptable_mangle". See previous discussion in this thread: https://lists.openwall.net/netdev/2020/06/03/161 . In the crash I found in iptable_mangle_hook() that state->net->ipv4.iptable_mangle=NULL causing a NULL pointer dereference. net->ipv4.iptable_mangle is set to NULL in +iptable_mangle_net_exit() and called when ip_mangle modules is unloaded. A rmmod task was found running in the crash dump. A 2nd crash showed the same problem when running "rmmod iptable_filter" (net->ipv4.iptable_filter=NULL). To fix this I added .pre_exit hook in all iptable_foo.c. The pre_exit will un-register the underlying hook and exit would do the table freeing. The netns core does an unconditional +synchronize_rcu after the pre_exit hooks insuring no packets are in flight that have picked up the pointer before completing the un-register. These patches include changes for both iptables and ip6tables. We tested this fix with ltp running iptables01.sh and iptables01.sh -6 a loop for 72 hours. 4) Add a selftest for conntrack helper assignment, from Florian Westphal. ==================== Signed-off-by: David S. Miller <[email protected]>
mrcsosa · Jun 25, 2020 · f4926d5 · f4926d5
2 parents 206e732 + 619ae8e
commit f4926d5
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Showing 58 changed files with 344 additions and 16 deletions.
diff --git a/include/linux/netfilter_ipv4/ip_tables.h b/include/linux/netfilter_ipv4/ip_tables.h
@@ -25,6 +25,12 @@
 int ipt_register_table(struct net *net, const struct xt_table *table,
 		       const struct ipt_replace *repl,
 		       const struct nf_hook_ops *ops, struct xt_table **res);
+
+void ipt_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+		       const struct nf_hook_ops *ops);
+
+void ipt_unregister_table_exit(struct net *net, struct xt_table *table);
+
 void ipt_unregister_table(struct net *net, struct xt_table *table,
 			  const struct nf_hook_ops *ops);
 

diff --git a/include/linux/netfilter_ipv6/ip6_tables.h b/include/linux/netfilter_ipv6/ip6_tables.h
@@ -29,6 +29,9 @@ int ip6t_register_table(struct net *net, const struct xt_table *table,
 			const struct nf_hook_ops *ops, struct xt_table **res);
 void ip6t_unregister_table(struct net *net, struct xt_table *table,
 			   const struct nf_hook_ops *ops);
+void ip6t_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+				    const struct nf_hook_ops *ops);
+void ip6t_unregister_table_exit(struct net *net, struct xt_table *table);
 extern unsigned int ip6t_do_table(struct sk_buff *skb,
 				  const struct nf_hook_state *state,
 				  struct xt_table *table);

diff --git a/net/bridge/netfilter/nft_meta_bridge.c b/net/bridge/netfilter/nft_meta_bridge.c
@@ -155,3 +155,4 @@ module_exit(nft_meta_bridge_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("wenxu <[email protected]>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "meta");
+MODULE_DESCRIPTION("Support for bridge dedicated meta key");
diff --git a/net/bridge/netfilter/nft_reject_bridge.c b/net/bridge/netfilter/nft_reject_bridge.c
@@ -455,3 +455,4 @@ module_exit(nft_reject_bridge_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <[email protected]>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "reject");
+MODULE_DESCRIPTION("Reject packets from bridge via nftables");
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
@@ -1797,11 +1797,22 @@ int ipt_register_table(struct net *net, const struct xt_table *table,
 	return ret;
 }
 
+void ipt_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+				   const struct nf_hook_ops *ops)
+{
+	nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+}
+
+void ipt_unregister_table_exit(struct net *net, struct xt_table *table)
+{
+	__ipt_unregister_table(net, table);
+}
+
 void ipt_unregister_table(struct net *net, struct xt_table *table,
 			  const struct nf_hook_ops *ops)
 {
 	if (ops)
-		nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+		ipt_unregister_table_pre_exit(net, table, ops);
 	__ipt_unregister_table(net, table);
 }
 
@@ -1958,6 +1969,8 @@ static void __exit ip_tables_fini(void)
 
 EXPORT_SYMBOL(ipt_register_table);
 EXPORT_SYMBOL(ipt_unregister_table);
+EXPORT_SYMBOL(ipt_unregister_table_pre_exit);
+EXPORT_SYMBOL(ipt_unregister_table_exit);
 EXPORT_SYMBOL(ipt_do_table);
 module_init(ip_tables_init);
 module_exit(ip_tables_fini);
diff --git a/net/ipv4/netfilter/ipt_SYNPROXY.c b/net/ipv4/netfilter/ipt_SYNPROXY.c
@@ -118,3 +118,4 @@ module_exit(synproxy_tg4_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <[email protected]>");
+MODULE_DESCRIPTION("Intercept TCP connections and establish them using syncookies");
diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c
@@ -72,16 +72,24 @@ static int __net_init iptable_filter_net_init(struct net *net)
 	return 0;
 }
 
+static void __net_exit iptable_filter_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_filter)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_filter,
+					      filter_ops);
+}
+
 static void __net_exit iptable_filter_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_filter)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_filter, filter_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_filter);
 	net->ipv4.iptable_filter = NULL;
 }
 
 static struct pernet_operations iptable_filter_net_ops = {
 	.init = iptable_filter_net_init,
+	.pre_exit = iptable_filter_net_pre_exit,
 	.exit = iptable_filter_net_exit,
 };
 

diff --git a/net/ipv4/netfilter/iptable_mangle.c b/net/ipv4/netfilter/iptable_mangle.c
@@ -100,15 +100,23 @@ static int __net_init iptable_mangle_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_mangle_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_mangle)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_mangle,
+					      mangle_ops);
+}
+
 static void __net_exit iptable_mangle_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_mangle)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_mangle, mangle_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_mangle);
 	net->ipv4.iptable_mangle = NULL;
 }
 
 static struct pernet_operations iptable_mangle_net_ops = {
+	.pre_exit = iptable_mangle_net_pre_exit,
 	.exit = iptable_mangle_net_exit,
 };
 

diff --git a/net/ipv4/netfilter/iptable_nat.c b/net/ipv4/netfilter/iptable_nat.c
@@ -113,16 +113,22 @@ static int __net_init iptable_nat_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_nat_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.nat_table)
+		ipt_nat_unregister_lookups(net);
+}
+
 static void __net_exit iptable_nat_net_exit(struct net *net)
 {
 	if (!net->ipv4.nat_table)
 		return;
-	ipt_nat_unregister_lookups(net);
-	ipt_unregister_table(net, net->ipv4.nat_table, NULL);
+	ipt_unregister_table_exit(net, net->ipv4.nat_table);
 	net->ipv4.nat_table = NULL;
 }
 
 static struct pernet_operations iptable_nat_net_ops = {
+	.pre_exit = iptable_nat_net_pre_exit,
 	.exit	= iptable_nat_net_exit,
 };
 

diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c
@@ -67,15 +67,23 @@ static int __net_init iptable_raw_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_raw_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_raw)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_raw,
+					      rawtable_ops);
+}
+
 static void __net_exit iptable_raw_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_raw)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_raw, rawtable_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_raw);
 	net->ipv4.iptable_raw = NULL;
 }
 
 static struct pernet_operations iptable_raw_net_ops = {
+	.pre_exit = iptable_raw_net_pre_exit,
 	.exit = iptable_raw_net_exit,
 };
 

diff --git a/net/ipv4/netfilter/iptable_security.c b/net/ipv4/netfilter/iptable_security.c
@@ -62,16 +62,23 @@ static int __net_init iptable_security_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_security_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_security)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_security,
+					      sectbl_ops);
+}
+
 static void __net_exit iptable_security_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_security)
 		return;
-
-	ipt_unregister_table(net, net->ipv4.iptable_security, sectbl_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_security);
 	net->ipv4.iptable_security = NULL;
 }
 
 static struct pernet_operations iptable_security_net_ops = {
+	.pre_exit = iptable_security_net_pre_exit,
 	.exit = iptable_security_net_exit,
 };
 

diff --git a/net/ipv4/netfilter/nf_flow_table_ipv4.c b/net/ipv4/netfilter/nf_flow_table_ipv4.c
@@ -34,3 +34,4 @@ module_exit(nf_flow_ipv4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <[email protected]>");
 MODULE_ALIAS_NF_FLOWTABLE(AF_INET);
+MODULE_DESCRIPTION("Netfilter flow table support");
diff --git a/net/ipv4/netfilter/nft_dup_ipv4.c b/net/ipv4/netfilter/nft_dup_ipv4.c
@@ -107,3 +107,4 @@ module_exit(nft_dup_ipv4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <[email protected]>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "dup");
+MODULE_DESCRIPTION("IPv4 nftables packet duplication support");
diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c
@@ -210,3 +210,4 @@ module_exit(nft_fib4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Florian Westphal <[email protected]>");
 MODULE_ALIAS_NFT_AF_EXPR(2, "fib");
+MODULE_DESCRIPTION("nftables fib / ip route lookup support");
diff --git a/net/ipv4/netfilter/nft_reject_ipv4.c b/net/ipv4/netfilter/nft_reject_ipv4.c
@@ -71,3 +71,4 @@ module_exit(nft_reject_ipv4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <[email protected]>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "reject");
+MODULE_DESCRIPTION("IPv4 packet rejection for nftables");
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
@@ -1807,11 +1807,22 @@ int ip6t_register_table(struct net *net, const struct xt_table *table,
 	return ret;
 }
 
+void ip6t_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+				    const struct nf_hook_ops *ops)
+{
+	nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+}
+
+void ip6t_unregister_table_exit(struct net *net, struct xt_table *table)
+{
+	__ip6t_unregister_table(net, table);
+}
+
 void ip6t_unregister_table(struct net *net, struct xt_table *table,
 			   const struct nf_hook_ops *ops)
 {
 	if (ops)
-		nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+		ip6t_unregister_table_pre_exit(net, table, ops);
 	__ip6t_unregister_table(net, table);
 }
 
@@ -1969,6 +1980,8 @@ static void __exit ip6_tables_fini(void)
 
 EXPORT_SYMBOL(ip6t_register_table);
 EXPORT_SYMBOL(ip6t_unregister_table);
+EXPORT_SYMBOL(ip6t_unregister_table_pre_exit);
+EXPORT_SYMBOL(ip6t_unregister_table_exit);
 EXPORT_SYMBOL(ip6t_do_table);
 
 module_init(ip6_tables_init);

diff --git a/net/ipv6/netfilter/ip6t_SYNPROXY.c b/net/ipv6/netfilter/ip6t_SYNPROXY.c
@@ -121,3 +121,4 @@ module_exit(synproxy_tg6_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <[email protected]>");
+MODULE_DESCRIPTION("Intercept IPv6 TCP connections and establish them using syncookies");
diff --git a/net/ipv6/netfilter/ip6table_filter.c b/net/ipv6/netfilter/ip6table_filter.c
@@ -73,16 +73,24 @@ static int __net_init ip6table_filter_net_init(struct net *net)
 	return 0;
 }
 
+static void __net_exit ip6table_filter_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_filter)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_filter,
+					       filter_ops);
+}
+
 static void __net_exit ip6table_filter_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_filter)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_filter, filter_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_filter);
 	net->ipv6.ip6table_filter = NULL;
 }
 
 static struct pernet_operations ip6table_filter_net_ops = {
 	.init = ip6table_filter_net_init,
+	.pre_exit = ip6table_filter_net_pre_exit,
 	.exit = ip6table_filter_net_exit,
 };
 

diff --git a/net/ipv6/netfilter/ip6table_mangle.c b/net/ipv6/netfilter/ip6table_mangle.c
@@ -93,16 +93,24 @@ static int __net_init ip6table_mangle_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_mangle_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_mangle)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_mangle,
+					       mangle_ops);
+}
+
 static void __net_exit ip6table_mangle_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_mangle)
 		return;
 
-	ip6t_unregister_table(net, net->ipv6.ip6table_mangle, mangle_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_mangle);
 	net->ipv6.ip6table_mangle = NULL;
 }
 
 static struct pernet_operations ip6table_mangle_net_ops = {
+	.pre_exit = ip6table_mangle_net_pre_exit,
 	.exit = ip6table_mangle_net_exit,
 };
 

diff --git a/net/ipv6/netfilter/ip6table_nat.c b/net/ipv6/netfilter/ip6table_nat.c
@@ -114,16 +114,22 @@ static int __net_init ip6table_nat_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_nat_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_nat)
+		ip6t_nat_unregister_lookups(net);
+}
+
 static void __net_exit ip6table_nat_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_nat)
 		return;
-	ip6t_nat_unregister_lookups(net);
-	ip6t_unregister_table(net, net->ipv6.ip6table_nat, NULL);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_nat);
 	net->ipv6.ip6table_nat = NULL;
 }
 
 static struct pernet_operations ip6table_nat_net_ops = {
+	.pre_exit = ip6table_nat_net_pre_exit,
 	.exit	= ip6table_nat_net_exit,
 };
 

diff --git a/net/ipv6/netfilter/ip6table_raw.c b/net/ipv6/netfilter/ip6table_raw.c
@@ -66,15 +66,23 @@ static int __net_init ip6table_raw_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_raw_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_raw)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_raw,
+					       rawtable_ops);
+}
+
 static void __net_exit ip6table_raw_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_raw)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_raw, rawtable_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_raw);
 	net->ipv6.ip6table_raw = NULL;
 }
 
 static struct pernet_operations ip6table_raw_net_ops = {
+	.pre_exit = ip6table_raw_net_pre_exit,
 	.exit = ip6table_raw_net_exit,
 };
 

diff --git a/net/ipv6/netfilter/ip6table_security.c b/net/ipv6/netfilter/ip6table_security.c
@@ -61,15 +61,23 @@ static int __net_init ip6table_security_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_security_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_security)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_security,
+					       sectbl_ops);
+}
+
 static void __net_exit ip6table_security_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_security)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_security, sectbl_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_security);
 	net->ipv6.ip6table_security = NULL;
 }
 
 static struct pernet_operations ip6table_security_net_ops = {
+	.pre_exit = ip6table_security_net_pre_exit,
 	.exit = ip6table_security_net_exit,
 };
 

diff --git a/net/ipv6/netfilter/nf_flow_table_ipv6.c b/net/ipv6/netfilter/nf_flow_table_ipv6.c
@@ -35,3 +35,4 @@ module_exit(nf_flow_ipv6_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <[email protected]>");
 MODULE_ALIAS_NF_FLOWTABLE(AF_INET6);
+MODULE_DESCRIPTION("Netfilter flow table IPv6 module");
diff --git a/net/ipv6/netfilter/nft_dup_ipv6.c b/net/ipv6/netfilter/nft_dup_ipv6.c
@@ -105,3 +105,4 @@ module_exit(nft_dup_ipv6_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <[email protected]>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup");
+MODULE_DESCRIPTION("IPv6 nftables packet duplication support");
diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c
@@ -255,3 +255,4 @@ module_exit(nft_fib6_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Florian Westphal <[email protected]>");
 MODULE_ALIAS_NFT_AF_EXPR(10, "fib");
+MODULE_DESCRIPTION("nftables fib / ipv6 route lookup support");