xref: /linux/net/unix/sysctl_net_unix.c (revision 2ea13d626216b539be6ec3afc53f64b5dd961146)
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/mm.h>
9  #include <linux/slab.h>
10  #include <linux/sysctl.h>
11  
12  #include <net/af_unix.h>
13  
14  static struct ctl_table unix_table[] = {
15  	{
16  		.procname	= "max_dgram_qlen",
17  		.data		= &init_net.unx.sysctl_max_dgram_qlen,
18  		.maxlen		= sizeof(int),
19  		.mode		= 0644,
20  		.proc_handler	= proc_dointvec
21  	},
22  	{ }
23  };
24  
25  int __net_init unix_sysctl_register(struct net *net)
26  {
27  	struct ctl_table *table;
28  
29  	if (net_eq(net, &init_net)) {
30  		table = unix_table;
31  	} else {
32  		table = kmemdup(unix_table, sizeof(unix_table), GFP_KERNEL);
33  		if (!table)
34  			goto err_alloc;
35  
36  		table[0].data = &net->unx.sysctl_max_dgram_qlen;
37  	}
38  
39  	net->unx.ctl = register_net_sysctl_sz(net, "net/unix", table,
40  					      ARRAY_SIZE(unix_table));
41  	if (net->unx.ctl == NULL)
42  		goto err_reg;
43  
44  	return 0;
45  
46  err_reg:
47  	if (!net_eq(net, &init_net))
48  		kfree(table);
49  err_alloc:
50  	return -ENOMEM;
51  }
52  
53  void unix_sysctl_unregister(struct net *net)
54  {
55  	struct ctl_table *table;
56  
57  	table = net->unx.ctl->ctl_table_arg;
58  	unregister_net_sysctl_table(net->unx.ctl);
59  	if (!net_eq(net, &init_net))
60  		kfree(table);
61  }
62