From 716ca530e1c4515d8683c9d5be3d56b301758b66 Mon Sep 17 00:00:00 2001
From: James <>
Date: Wed, 4 Nov 2015 11:49:21 +0000
Subject: trunk-47381

---
 .../611-netfilter_match_bypass_default_table.patch | 94 ++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 target/linux/generic/patches-3.18/611-netfilter_match_bypass_default_table.patch

(limited to 'target/linux/generic/patches-3.18/611-netfilter_match_bypass_default_table.patch')

diff --git a/target/linux/generic/patches-3.18/611-netfilter_match_bypass_default_table.patch b/target/linux/generic/patches-3.18/611-netfilter_match_bypass_default_table.patch
new file mode 100644
index 0000000..ef993c8
--- /dev/null
+++ b/target/linux/generic/patches-3.18/611-netfilter_match_bypass_default_table.patch
@@ -0,0 +1,94 @@
+--- a/net/ipv4/netfilter/ip_tables.c
++++ b/net/ipv4/netfilter/ip_tables.c
+@@ -310,6 +310,33 @@ struct ipt_entry *ipt_next_entry(const s
+ 	return (void *)entry + entry->next_offset;
+ }
+ 
++static bool
++ipt_handle_default_rule(struct ipt_entry *e, unsigned int *verdict)
++{
++	struct xt_entry_target *t;
++	struct xt_standard_target *st;
++
++	if (e->target_offset != sizeof(struct ipt_entry))
++		return false;
++
++	if (!(e->ip.flags & IPT_F_NO_DEF_MATCH))
++		return false;
++
++	t = ipt_get_target(e);
++	if (t->u.kernel.target->target)
++		return false;
++
++	st = (struct xt_standard_target *) t;
++	if (st->verdict == XT_RETURN)
++		return false;
++
++	if (st->verdict >= 0)
++		return false;
++
++	*verdict = (unsigned)(-st->verdict) - 1;
++	return true;
++}
++
+ /* Returns one of the generic firewall policies, like NF_ACCEPT. */
+ unsigned int
+ ipt_do_table(struct sk_buff *skb,
+@@ -331,9 +358,33 @@ ipt_do_table(struct sk_buff *skb,
+ 	unsigned int addend;
+ 
+ 	/* Initialization */
++	IP_NF_ASSERT(table->valid_hooks & (1 << hook));
++	local_bh_disable();
++	private = table->private;
++	cpu        = smp_processor_id();
++	/*
++	 * Ensure we load private-> members after we've fetched the base
++	 * pointer.
++	 */
++	smp_read_barrier_depends();
++	table_base = private->entries[cpu];
++
++	e = get_entry(table_base, private->hook_entry[hook]);
++	if (ipt_handle_default_rule(e, &verdict)) {
++		ADD_COUNTER(e->counters, skb->len, 1);
++		local_bh_enable();
++		return verdict;
++	}
++
+ 	ip = ip_hdr(skb);
+ 	indev = in ? in->name : nulldevname;
+ 	outdev = out ? out->name : nulldevname;
++
++	addend = xt_write_recseq_begin();
++	jumpstack  = (struct ipt_entry **)private->jumpstack[cpu];
++	stackptr   = per_cpu_ptr(private->stackptr, cpu);
++	origptr    = *stackptr;
++
+ 	/* We handle fragments by dealing with the first fragment as
+ 	 * if it was a normal packet.  All other fragments are treated
+ 	 * normally, except that they will NEVER match rules that ask
+@@ -348,23 +399,6 @@ ipt_do_table(struct sk_buff *skb,
+ 	acpar.family  = NFPROTO_IPV4;
+ 	acpar.hooknum = hook;
+ 
+-	IP_NF_ASSERT(table->valid_hooks & (1 << hook));
+-	local_bh_disable();
+-	addend = xt_write_recseq_begin();
+-	private = table->private;
+-	cpu        = smp_processor_id();
+-	/*
+-	 * Ensure we load private-> members after we've fetched the base
+-	 * pointer.
+-	 */
+-	smp_read_barrier_depends();
+-	table_base = private->entries[cpu];
+-	jumpstack  = (struct ipt_entry **)private->jumpstack[cpu];
+-	stackptr   = per_cpu_ptr(private->stackptr, cpu);
+-	origptr    = *stackptr;
+-
+-	e = get_entry(table_base, private->hook_entry[hook]);
+-
+ 	pr_debug("Entering %s(hook %u); sp at %u (UF %p)\n",
+ 		 table->name, hook, origptr,
+ 		 get_entry(table_base, private->underflow[hook]));
-- 
cgit v1.2.3