ip_tables: fix table locking in ipt_do_table

[NETFILTER]: ip_tables: fix table locking in ipt_do_table

table->private might change because of ruleset changes, don't use it without
holding the lock.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index d0d19192026d9eb2327cf68a47a4ba1b23dc7fe5..92adfebec0a058f8da5acaa12874535077f3f7da 100644 (file)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -237,7 +237,7 @@ unsigned int arpt_do_table(struct sk_buff **pskb,
        struct arpt_entry *e, *back;
        const char *indev, *outdev;
        void *table_base;
-       struct xt_table_info *private = table->private;
+       struct xt_table_info *private;
 
        /* ARP header, plus 2 device addresses, plus 2 IP addresses.  */
        if (!pskb_may_pull((*pskb), (sizeof(struct arphdr) +
@@ -249,6 +249,7 @@ unsigned int arpt_do_table(struct sk_buff **pskb,
        outdev = out ? out->name : nulldevname;
 
        read_lock_bh(&table->lock);
+       private = table->private;
        table_base = (void *)private->entries[smp_processor_id()];
        e = get_entry(table_base, private->hook_entry[hook]);
        back = get_entry(table_base, private->underflow[hook]);

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index cee3397ec27765dcdeab77890847ac59b2cb2434..71871c4f9c20c2e5bbbdbf9ecdaef8cbfa772f6d 100644 (file)
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -231,7 +231,7 @@ ipt_do_table(struct sk_buff **pskb,
        const char *indev, *outdev;
        void *table_base;
        struct ipt_entry *e, *back;
-       struct xt_table_info *private = table->private;
+       struct xt_table_info *private;
 
        /* Initialization */
        ip = (*pskb)->nh.iph;
@@ -248,6 +248,7 @@ ipt_do_table(struct sk_buff **pskb,
 
        read_lock_bh(&table->lock);
        IP_NF_ASSERT(table->valid_hooks & (1 << hook));
+       private = table->private;
        table_base = (void *)private->entries[smp_processor_id()];
        e = get_entry(table_base, private->hook_entry[hook]);