netfilter: xtables: compat out of scope fix
As per C99 6.2.4(2) when temporary table data goes out of scope,
the behaviour is undefined:
if (compat) {
struct foo tmp;
...
private = &tmp;
}
[dereference private]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 0663276..90203e1 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -925,10 +925,10 @@
if (t && !IS_ERR(t)) {
struct arpt_getinfo info;
const struct xt_table_info *private = t->private;
-
#ifdef CONFIG_COMPAT
+ struct xt_table_info tmp;
+
if (compat) {
- struct xt_table_info tmp;
ret = compat_table_info(private, &tmp);
xt_compat_flush_offsets(NFPROTO_ARP);
private = &tmp;
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 572330a..3ce53cf 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1132,10 +1132,10 @@
if (t && !IS_ERR(t)) {
struct ipt_getinfo info;
const struct xt_table_info *private = t->private;
-
#ifdef CONFIG_COMPAT
+ struct xt_table_info tmp;
+
if (compat) {
- struct xt_table_info tmp;
ret = compat_table_info(private, &tmp);
xt_compat_flush_offsets(AF_INET);
private = &tmp;
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 480d7f8..8a7e0f5 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1164,10 +1164,10 @@
if (t && !IS_ERR(t)) {
struct ip6t_getinfo info;
const struct xt_table_info *private = t->private;
-
#ifdef CONFIG_COMPAT
+ struct xt_table_info tmp;
+
if (compat) {
- struct xt_table_info tmp;
ret = compat_table_info(private, &tmp);
xt_compat_flush_offsets(AF_INET6);
private = &tmp;