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 your net tree. This batch
mostly comes with patches to address fallout from the previous merge window
cycle, they are:

1) Use entry->state.hook_list from nf_queue() instead of the global nf_hooks
   which is not valid when used from NFPROTO_NETDEV, this should cause no
   problems though since we have no userspace queueing for that family, but
   let's fix this now for the sake of correctness. Patch from Eric W. Biederman.

2) Fix compilation breakage in bridge netfilter if CONFIG_NF_DEFRAG_IPV4 is not
   set, from Bernhard Thaler.

3) Use percpu jumpstack in arptables too, now that there's a single copy of the
   rule blob we can't store the return address there anymore. Patch from
   Florian Westphal.

4) Fix a skb leak in the xmit path of bridge netfilter, problem there since
   2.6.37 although it should be not possible to hit invalid traffic there, also
   from Florian.

5) Eric Leblond reports that when loading a large ruleset with many missing
   modules after a fresh boot, nf_tables can take long time commit it. Fix this
   by processing the full batch until the end, even on missing modules, then
   abort only once and restart processing.

6) Add bridge netfilter files to the MAINTAINER files.

7) Fix a net_device refcount leak in the new IPV6 bridge netfilter code, from
   Julien Grall.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 9 deletions

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 95c9b6eece25..92305a1a021a 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -254,9 +254,10 @@ unsigned int arpt_do_table(struct sk_buff *skb,
 	static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long))));
 	unsigned int verdict = NF_DROP;
 	const struct arphdr *arp;
-	struct arpt_entry *e, *back;
+	struct arpt_entry *e, **jumpstack;
 	const char *indev, *outdev;
 	const void *table_base;
+	unsigned int cpu, stackidx = 0;
 	const struct xt_table_info *private;
 	struct xt_action_param acpar;
 	unsigned int addend;
@@ -270,15 +271,16 @@ unsigned int arpt_do_table(struct sk_buff *skb,
 	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;
+	jumpstack  = (struct arpt_entry **)private->jumpstack[cpu];
 
 	e = get_entry(table_base, private->hook_entry[hook]);
-	back = get_entry(table_base, private->underflow[hook]);
 
 	acpar.in      = state->in;
 	acpar.out     = state->out;
@@ -312,18 +314,23 @@ unsigned int arpt_do_table(struct sk_buff *skb,
 					verdict = (unsigned int)(-v) - 1;
 					break;
 				}
-				e = back;
-				back = get_entry(table_base, back->comefrom);
+				if (stackidx == 0) {
+					e = get_entry(table_base,
+						      private->underflow[hook]);
+				} else {
+					e = jumpstack[--stackidx];
+					e = arpt_next_entry(e);
+				}
 				continue;
 			}
 			if (table_base + v
 			    != arpt_next_entry(e)) {
-				/* Save old back ptr in next entry */
-				struct arpt_entry *next = arpt_next_entry(e);
-				next->comefrom = (void *)back - table_base;
 
-				/* set back pointer to next entry */
-				back = next;
+				if (stackidx >= private->stacksize) {
+					verdict = NF_DROP;
+					break;
+				}
+				jumpstack[stackidx++] = e;
 			}
 
 			e = get_entry(table_base, v);