From 14c7dbe043d01a83a30633ab6b109ba2ac61d9f7 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Mon, 8 Feb 2010 11:17:43 -0800 Subject: [PATCH] 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 Cc: stable@kernel.org Signed-off-by: Patrick McHardy --- net/ipv4/netfilter/arp_tables.c | 4 ++-- net/ipv4/netfilter/ip_tables.c | 4 ++-- net/ipv6/netfilter/ip6_tables.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 06632762ba5f..90203e1b9187 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -925,10 +925,10 @@ static int get_info(struct net *net, void __user *user, int *len, int compat) 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 572330a552ef..3ce53cf13d5a 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1132,10 +1132,10 @@ static int get_info(struct net *net, void __user *user, int *len, int compat) 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 480d7f8c9802..8a7e0f52e177 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -1164,10 +1164,10 @@ static int get_info(struct net *net, void __user *user, int *len, int compat) 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; -- 2.20.1