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11#include <asm/uaccess.h>
12
13#include <linux/errno.h>
14#include <linux/time.h>
15#include <linux/proc_fs.h>
16#include <linux/stat.h>
17#include <linux/slab.h>
18#include <linux/init.h>
19#include <linux/sched.h>
20#include <linux/module.h>
21#include <linux/bitops.h>
22#include <linux/mount.h>
23#include <linux/nsproxy.h>
24#include <net/net_namespace.h>
25#include <linux/seq_file.h>
26
27#include "internal.h"
28
29
30static struct net *get_proc_net(const struct inode *inode)
31{
32 return maybe_get_net(PDE_NET(PDE(inode)));
33}
34
35int seq_open_net(struct inode *ino, struct file *f,
36 const struct seq_operations *ops, int size)
37{
38 struct net *net;
39 struct seq_net_private *p;
40
41 BUG_ON(size < sizeof(*p));
42
43 net = get_proc_net(ino);
44 if (net == NULL)
45 return -ENXIO;
46
47 p = __seq_open_private(f, ops, size);
48 if (p == NULL) {
49 put_net(net);
50 return -ENOMEM;
51 }
52#ifdef CONFIG_NET_NS
53 p->net = net;
54#endif
55 return 0;
56}
57EXPORT_SYMBOL_GPL(seq_open_net);
58
59int single_open_net(struct inode *inode, struct file *file,
60 int (*show)(struct seq_file *, void *))
61{
62 int err;
63 struct net *net;
64
65 err = -ENXIO;
66 net = get_proc_net(inode);
67 if (net == NULL)
68 goto err_net;
69
70 err = single_open(file, show, net);
71 if (err < 0)
72 goto err_open;
73
74 return 0;
75
76err_open:
77 put_net(net);
78err_net:
79 return err;
80}
81EXPORT_SYMBOL_GPL(single_open_net);
82
83int seq_release_net(struct inode *ino, struct file *f)
84{
85 struct seq_file *seq;
86
87 seq = f->private_data;
88
89 put_net(seq_file_net(seq));
90 seq_release_private(ino, f);
91 return 0;
92}
93EXPORT_SYMBOL_GPL(seq_release_net);
94
95int single_release_net(struct inode *ino, struct file *f)
96{
97 struct seq_file *seq = f->private_data;
98 put_net(seq->private);
99 return single_release(ino, f);
100}
101EXPORT_SYMBOL_GPL(single_release_net);
102
103static struct net *get_proc_task_net(struct inode *dir)
104{
105 struct task_struct *task;
106 struct nsproxy *ns;
107 struct net *net = NULL;
108
109 rcu_read_lock();
110 task = pid_task(proc_pid(dir), PIDTYPE_PID);
111 if (task != NULL) {
112 ns = task_nsproxy(task);
113 if (ns != NULL)
114 net = get_net(ns->net_ns);
115 }
116 rcu_read_unlock();
117
118 return net;
119}
120
121static struct dentry *proc_tgid_net_lookup(struct inode *dir,
122 struct dentry *dentry, struct nameidata *nd)
123{
124 struct dentry *de;
125 struct net *net;
126
127 de = ERR_PTR(-ENOENT);
128 net = get_proc_task_net(dir);
129 if (net != NULL) {
130 de = proc_lookup_de(net->proc_net, dir, dentry);
131 put_net(net);
132 }
133 return de;
134}
135
136static int proc_tgid_net_getattr(struct vfsmount *mnt, struct dentry *dentry,
137 struct kstat *stat)
138{
139 struct inode *inode = dentry->d_inode;
140 struct net *net;
141
142 net = get_proc_task_net(inode);
143
144 generic_fillattr(inode, stat);
145
146 if (net != NULL) {
147 stat->nlink = net->proc_net->nlink;
148 put_net(net);
149 }
150
151 return 0;
152}
153
154const struct inode_operations proc_net_inode_operations = {
155 .lookup = proc_tgid_net_lookup,
156 .getattr = proc_tgid_net_getattr,
157};
158
159static int proc_tgid_net_readdir(struct file *filp, void *dirent,
160 filldir_t filldir)
161{
162 int ret;
163 struct net *net;
164
165 ret = -EINVAL;
166 net = get_proc_task_net(filp->f_path.dentry->d_inode);
167 if (net != NULL) {
168 ret = proc_readdir_de(net->proc_net, filp, dirent, filldir);
169 put_net(net);
170 }
171 return ret;
172}
173
174const struct file_operations proc_net_operations = {
175 .llseek = generic_file_llseek,
176 .read = generic_read_dir,
177 .readdir = proc_tgid_net_readdir,
178};
179
180
181struct proc_dir_entry *proc_net_fops_create(struct net *net,
182 const char *name, umode_t mode, const struct file_operations *fops)
183{
184 return proc_create(name, mode, net->proc_net, fops);
185}
186EXPORT_SYMBOL_GPL(proc_net_fops_create);
187
188void proc_net_remove(struct net *net, const char *name)
189{
190 remove_proc_entry(name, net->proc_net);
191}
192EXPORT_SYMBOL_GPL(proc_net_remove);
193
194static __net_init int proc_net_ns_init(struct net *net)
195{
196 struct proc_dir_entry *netd, *net_statd;
197 int err;
198
199 err = -ENOMEM;
200 netd = kzalloc(sizeof(*netd) + 4, GFP_KERNEL);
201 if (!netd)
202 goto out;
203
204 netd->data = net;
205 netd->nlink = 2;
206 netd->namelen = 3;
207 netd->parent = &proc_root;
208 memcpy(netd->name, "net", 4);
209
210 err = -EEXIST;
211 net_statd = proc_net_mkdir(net, "stat", netd);
212 if (!net_statd)
213 goto free_net;
214
215 net->proc_net = netd;
216 net->proc_net_stat = net_statd;
217 return 0;
218
219free_net:
220 kfree(netd);
221out:
222 return err;
223}
224
225static __net_exit void proc_net_ns_exit(struct net *net)
226{
227 remove_proc_entry("stat", net->proc_net);
228 kfree(net->proc_net);
229}
230
231static struct pernet_operations __net_initdata proc_net_ns_ops = {
232 .init = proc_net_ns_init,
233 .exit = proc_net_ns_exit,
234};
235
236int __init proc_net_init(void)
237{
238 proc_symlink("net", NULL, "self/net");
239
240 return register_pernet_subsys(&proc_net_ns_ops);
241}
242
