netfilter: xt_recent: use proc_create_data()

Fixes a crash in recent_seq_start:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000100
IP: [<ffffffffa002119c>] recent_seq_start+0x4c/0x90 [xt_recent]
PGD 17d33c067 PUD 107afe067 PMD 0
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
CPU 0
Modules linked in: ipt_LOG xt_recent af_packet iptable_nat nf_nat nf_conntrack_ipv4 nf_conntrack nf_defrag_ipv4 xt_tcpudp iptable_filter ip_tables x_tables ext2 nls_utf8 fuse sr_mod cdrom [last unloaded: ntfs]
Pid: 32373, comm: cat Not tainted 2.6.27-04ab591808565f968d4406f6435090ad671ebdab #6
RIP: 0010:[<ffffffffa002119c>]  [<ffffffffa002119c>] recent_seq_start+0x4c/0x90 [xt_recent]
RSP: 0018:ffff88015fed7e28  EFLAGS: 00010246
...

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
index 4ebd4ca9a991bf871a23bf672ea2b30d5a9095d7..280c471bcdf444fdc2228a46895c2b44baf8d549 100644 (file)
--- a/net/netfilter/xt_recent.c
+++ b/net/netfilter/xt_recent.c
@@ -318,15 +318,15 @@ static bool recent_mt_check(const struct xt_mtchk_param *par)
        for (i = 0; i < ip_list_hash_size; i++)
                INIT_LIST_HEAD(&t->iphash[i]);
 #ifdef CONFIG_PROC_FS
-       t->proc = proc_create(t->name, ip_list_perms, recent_proc_dir,
-                 &recent_mt_fops);
+       t->proc = proc_create_data(t->name, ip_list_perms, recent_proc_dir,
+                 &recent_mt_fops, t);
        if (t->proc == NULL) {
                kfree(t);
                goto out;
        }
 #ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
-       t->proc_old = proc_create(t->name, ip_list_perms, proc_old_dir,
-                     &recent_old_fops);
+       t->proc_old = proc_create_data(t->name, ip_list_perms, proc_old_dir,
+                     &recent_old_fops, t);
        if (t->proc_old == NULL) {
                remove_proc_entry(t->name, proc_old_dir);
                kfree(t);
@@ -334,11 +334,9 @@ static bool recent_mt_check(const struct xt_mtchk_param *par)
        }
        t->proc_old->uid   = ip_list_uid;
        t->proc_old->gid   = ip_list_gid;
-       t->proc_old->data  = t;
 #endif
        t->proc->uid       = ip_list_uid;
        t->proc->gid       = ip_list_gid;
-       t->proc->data      = t;
 #endif
        spin_lock_bh(&recent_lock);
        list_add_tail(&t->list, &tables);