sysctl_net_unix.c

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 * NET4:	Sysctl interface to net af_unix subsystem.
 4 *
 5 * Authors:	Mike Shaver.
 6 */
 7
 8#include <linux/slab.h>
 9#include <linux/string.h>
10#include <linux/sysctl.h>
11#include <net/af_unix.h>
12#include <net/net_namespace.h>
13
14#include "af_unix.h"
15
16static struct ctl_table unix_table[] = {
17	{
18		.procname	= "max_dgram_qlen",
19		.data		= &init_net.unx.sysctl_max_dgram_qlen,
20		.maxlen		= sizeof(int),
21		.mode		= 0644,
22		.proc_handler	= proc_dointvec
23	},
24};
25
26int __net_init unix_sysctl_register(struct net *net)
27{
28	struct ctl_table *table;
29
30	if (net_eq(net, &init_net)) {
31		table = unix_table;
32	} else {
33		table = kmemdup(unix_table, sizeof(unix_table), GFP_KERNEL);
34		if (!table)
35			goto err_alloc;
36
37		table[0].data = &net->unx.sysctl_max_dgram_qlen;
38	}
39
40	net->unx.ctl = register_net_sysctl_sz(net, "net/unix", table,
41					      ARRAY_SIZE(unix_table));
42	if (net->unx.ctl == NULL)
43		goto err_reg;
44
45	return 0;
46
47err_reg:
48	if (!net_eq(net, &init_net))
49		kfree(table);
50err_alloc:
51	return -ENOMEM;
52}
53
54void unix_sysctl_unregister(struct net *net)
55{
56	const struct ctl_table *table;
57
58	table = net->unx.ctl->ctl_table_arg;
59	unregister_net_sysctl_table(net->unx.ctl);
60	if (!net_eq(net, &init_net))
61		kfree(table);
62}