Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:
====================
The following patchset contains three netfilter fixes for your net
tree, they are:
* A couple of fixes to resolve info leak to userspace due to uninitialized
memory area in ulogd, from Mathias Krause.
* Fix instruction ordering issues that may lead to the access of
uninitialized data in x_tables. The problem involves the table update
(producer) and the main packet matching (consumer) routines. Detected in
SMP ARMv7, from Will Deacon.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/netfilter/ebt_ulog.c b/net/bridge/netfilter/ebt_ulog.c
index 5180938..7c470c3 100644
--- a/net/bridge/netfilter/ebt_ulog.c
+++ b/net/bridge/netfilter/ebt_ulog.c
@@ -181,6 +181,7 @@
ub->qlen++;
pm = nlmsg_data(nlh);
+ memset(pm, 0, sizeof(*pm));
/* Fill in the ulog data */
pm->version = EBT_ULOG_VERSION;
@@ -193,8 +194,6 @@
pm->hook = hooknr;
if (uloginfo->prefix != NULL)
strcpy(pm->prefix, uloginfo->prefix);
- else
- *(pm->prefix) = '\0';
if (in) {
strcpy(pm->physindev, in->name);
@@ -204,16 +203,14 @@
strcpy(pm->indev, br_port_get_rcu(in)->br->dev->name);
else
strcpy(pm->indev, in->name);
- } else
- pm->indev[0] = pm->physindev[0] = '\0';
+ }
if (out) {
/* If out exists, then out is a bridge port */
strcpy(pm->physoutdev, out->name);
/* rcu_read_lock()ed by nf_hook_slow */
strcpy(pm->outdev, br_port_get_rcu(out)->br->dev->name);
- } else
- pm->outdev[0] = pm->physoutdev[0] = '\0';
+ }
if (skb_copy_bits(skb, -ETH_HLEN, pm->data, copy_len) < 0)
BUG();
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 85a4f21..59da7cd 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -271,6 +271,11 @@
local_bh_disable();
addend = xt_write_recseq_begin();
private = table->private;
+ /*
+ * Ensure we load private-> members after we've fetched the base
+ * pointer.
+ */
+ smp_read_barrier_depends();
table_base = private->entries[smp_processor_id()];
e = get_entry(table_base, private->hook_entry[hook]);
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index d23118d..718dfbd 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -327,6 +327,11 @@
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);
diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c
index cbc2215..9cb993c 100644
--- a/net/ipv4/netfilter/ipt_ULOG.c
+++ b/net/ipv4/netfilter/ipt_ULOG.c
@@ -220,6 +220,7 @@
ub->qlen++;
pm = nlmsg_data(nlh);
+ memset(pm, 0, sizeof(*pm));
/* We might not have a timestamp, get one */
if (skb->tstamp.tv64 == 0)
@@ -238,8 +239,6 @@
}
else if (loginfo->prefix[0] != '\0')
strncpy(pm->prefix, loginfo->prefix, sizeof(pm->prefix));
- else
- *(pm->prefix) = '\0';
if (in && in->hard_header_len > 0 &&
skb->mac_header != skb->network_header &&
@@ -251,13 +250,9 @@
if (in)
strncpy(pm->indev_name, in->name, sizeof(pm->indev_name));
- else
- pm->indev_name[0] = '\0';
if (out)
strncpy(pm->outdev_name, out->name, sizeof(pm->outdev_name));
- else
- pm->outdev_name[0] = '\0';
/* copy_len <= skb->len, so can't fail. */
if (skb_copy_bits(skb, 0, pm->payload, copy_len) < 0)
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 44400c2..710238f 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -349,6 +349,11 @@
local_bh_disable();
addend = xt_write_recseq_begin();
private = table->private;
+ /*
+ * Ensure we load private-> members after we've fetched the base
+ * pointer.
+ */
+ smp_read_barrier_depends();
cpu = smp_processor_id();
table_base = private->entries[cpu];
jumpstack = (struct ip6t_entry **)private->jumpstack[cpu];
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 8b03028..227aa11 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -845,8 +845,13 @@
return NULL;
}
- table->private = newinfo;
newinfo->initial_entries = private->initial_entries;
+ /*
+ * Ensure contents of newinfo are visible before assigning to
+ * private.
+ */
+ smp_wmb();
+ table->private = newinfo;
/*
* Even though table entries have now been swapped, other CPU's