xref: /linux/net/unix/sysctl_net_unix.c (revision 6a8ec0b65e4c2ade040397819d8723a42fc352f4)
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  int __net_init unix_sysctl_register(struct net *net)
25  {
26  	struct ctl_table *table;
27  
28  	if (net_eq(net, &init_net)) {
29  		table = unix_table;
30  	} else {
31  		table = kmemdup(unix_table, sizeof(unix_table), GFP_KERNEL);
32  		if (!table)
33  			goto err_alloc;
34  
35  		table[0].data = &net->unx.sysctl_max_dgram_qlen;
36  	}
37  
38  	net->unx.ctl = register_net_sysctl_sz(net, "net/unix", table,
39  					      ARRAY_SIZE(unix_table));
40  	if (net->unx.ctl == NULL)
41  		goto err_reg;
42  
43  	return 0;
44  
45  err_reg:
46  	if (!net_eq(net, &init_net))
47  		kfree(table);
48  err_alloc:
49  	return -ENOMEM;
50  }
51  
52  void unix_sysctl_unregister(struct net *net)
53  {
54  	const struct ctl_table *table;
55  
56  	table = net->unx.ctl->ctl_table_arg;
57  	unregister_net_sysctl_table(net->unx.ctl);
58  	if (!net_eq(net, &init_net))
59  		kfree(table);
60  }
61