xref: /openbmc/linux/net/unix/sysctl_net_unix.c (revision 9cfc5c90)
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 
18 static 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 
29 int __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 
48 err_reg:
49 	kfree(table);
50 err_alloc:
51 	return -ENOMEM;
52 }
53 
54 void 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