1/*
2 * NET4:	Sysctl interface to net af_unix subsystem.
3 *
4 * Authors:	Mike Shaver.
5 *
6 *		This program is free software; you can redistribute it and/or
7 *		modify it under the terms of the GNU General Public License
8 *		as published by the Free Software Foundation; either version
9 *		2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/mm.h>
13#include <linux/slab.h>
14#include <linux/sysctl.h>
15
16#include <net/af_unix.h>
17
18static struct ctl_table unix_table[] = {
19	{
20		.procname	= "max_dgram_qlen",
21		.data		= &init_net.unx.sysctl_max_dgram_qlen,
22		.maxlen		= sizeof(int),
23		.mode		= 0644,
24		.proc_handler	= proc_dointvec
25	},
26	{ }
27};
28
29int __net_init unix_sysctl_register(struct net *net)
30{
31	struct ctl_table *table;
32
33	table = kmemdup(unix_table, sizeof(unix_table), GFP_KERNEL);
34	if (table == NULL)
35		goto err_alloc;
36
37	/* Don't export sysctls to unprivileged users */
38	if (net->user_ns != &init_user_ns)
39		table[0].procname = NULL;
40
41	table[0].data = &net->unx.sysctl_max_dgram_qlen;
42	net->unx.ctl = register_net_sysctl(net, "net/unix", table);
43	if (net->unx.ctl == NULL)
44		goto err_reg;
45
46	return 0;
47
48err_reg:
49	kfree(table);
50err_alloc:
51	return -ENOMEM;
52}
53
54void unix_sysctl_unregister(struct net *net)
55{
56	struct ctl_table *table;
57
58	table = net->unx.ctl->ctl_table_arg;
59	unregister_net_sysctl_table(net->unx.ctl);
60	kfree(table);
61}
62