1/*
  2 *  linux/fs/proc/net.c
  3 *
  4 *  Copyright (C) 2007
  5 *
  6 *  Author: Eric Biederman <ebiederm@xmission.com>
  7 *
  8 *  proc net directory handling functions
  9 */
 10
 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
 29static inline struct net *PDE_NET(struct proc_dir_entry *pde)
 30{
 31	return pde->parent->data;
 32}
 33
 34static struct net *get_proc_net(const struct inode *inode)
 35{
 36	return maybe_get_net(PDE_NET(PDE(inode)));
 37}
 38
 39int seq_open_net(struct inode *ino, struct file *f,
 40		 const struct seq_operations *ops, int size)
 41{
 42	struct net *net;
 43	struct seq_net_private *p;
 44
 45	BUG_ON(size < sizeof(*p));
 46
 47	net = get_proc_net(ino);
 48	if (net == NULL)
 49		return -ENXIO;
 50
 51	p = __seq_open_private(f, ops, size);
 52	if (p == NULL) {
 53		put_net(net);
 54		return -ENOMEM;
 55	}
 56#ifdef CONFIG_NET_NS
 57	p->net = net;
 58#endif
 59	return 0;
 60}
 61EXPORT_SYMBOL_GPL(seq_open_net);
 62
 63int single_open_net(struct inode *inode, struct file *file,
 64		int (*show)(struct seq_file *, void *))
 65{
 66	int err;
 67	struct net *net;
 68
 69	err = -ENXIO;
 70	net = get_proc_net(inode);
 71	if (net == NULL)
 72		goto err_net;
 73
 74	err = single_open(file, show, net);
 75	if (err < 0)
 76		goto err_open;
 77
 78	return 0;
 79
 80err_open:
 81	put_net(net);
 82err_net:
 83	return err;
 84}
 85EXPORT_SYMBOL_GPL(single_open_net);
 86
 87int seq_release_net(struct inode *ino, struct file *f)
 88{
 89	struct seq_file *seq;
 90
 91	seq = f->private_data;
 92
 93	put_net(seq_file_net(seq));
 94	seq_release_private(ino, f);
 95	return 0;
 96}
 97EXPORT_SYMBOL_GPL(seq_release_net);
 98
 99int single_release_net(struct inode *ino, struct file *f)
100{
101	struct seq_file *seq = f->private_data;
102	put_net(seq->private);
103	return single_release(ino, f);
104}
105EXPORT_SYMBOL_GPL(single_release_net);
106
107static struct net *get_proc_task_net(struct inode *dir)
108{
109	struct task_struct *task;
110	struct nsproxy *ns;
111	struct net *net = NULL;
112
113	rcu_read_lock();
114	task = pid_task(proc_pid(dir), PIDTYPE_PID);
115	if (task != NULL) {
116		task_lock(task);
117		ns = task->nsproxy;
118		if (ns != NULL)
119			net = get_net(ns->net_ns);
120		task_unlock(task);
121	}
122	rcu_read_unlock();
123
124	return net;
125}
126
127static struct dentry *proc_tgid_net_lookup(struct inode *dir,
128		struct dentry *dentry, unsigned int flags)
129{
130	struct dentry *de;
131	struct net *net;
132
133	de = ERR_PTR(-ENOENT);
134	net = get_proc_task_net(dir);
135	if (net != NULL) {
136		de = proc_lookup_de(net->proc_net, dir, dentry);
137		put_net(net);
138	}
139	return de;
140}
141
142static int proc_tgid_net_getattr(struct vfsmount *mnt, struct dentry *dentry,
143		struct kstat *stat)
144{
145	struct inode *inode = d_inode(dentry);
146	struct net *net;
147
148	net = get_proc_task_net(inode);
149
150	generic_fillattr(inode, stat);
151
152	if (net != NULL) {
153		stat->nlink = net->proc_net->nlink;
154		put_net(net);
155	}
156
157	return 0;
158}
159
160const struct inode_operations proc_net_inode_operations = {
161	.lookup		= proc_tgid_net_lookup,
162	.getattr	= proc_tgid_net_getattr,
163};
164
165static int proc_tgid_net_readdir(struct file *file, struct dir_context *ctx)
166{
167	int ret;
168	struct net *net;
169
170	ret = -EINVAL;
171	net = get_proc_task_net(file_inode(file));
172	if (net != NULL) {
173		ret = proc_readdir_de(net->proc_net, file, ctx);
174		put_net(net);
175	}
176	return ret;
177}
178
179const struct file_operations proc_net_operations = {
180	.llseek		= generic_file_llseek,
181	.read		= generic_read_dir,
182	.iterate	= proc_tgid_net_readdir,
183};
184
185static __net_init int proc_net_ns_init(struct net *net)
186{
187	struct proc_dir_entry *netd, *net_statd;
 
 
188	int err;
189
190	err = -ENOMEM;
191	netd = kzalloc(sizeof(*netd) + 4, GFP_KERNEL);
192	if (!netd)
193		goto out;
194
195	netd->subdir = RB_ROOT;
196	netd->data = net;
197	netd->nlink = 2;
198	netd->namelen = 3;
199	netd->parent = &proc_root;
 
200	memcpy(netd->name, "net", 4);
201
 
 
 
 
 
 
 
 
 
 
202	err = -EEXIST;
203	net_statd = proc_net_mkdir(net, "stat", netd);
204	if (!net_statd)
205		goto free_net;
206
207	net->proc_net = netd;
208	net->proc_net_stat = net_statd;
209	return 0;
210
211free_net:
212	kfree(netd);
213out:
214	return err;
215}
216
217static __net_exit void proc_net_ns_exit(struct net *net)
218{
219	remove_proc_entry("stat", net->proc_net);
220	kfree(net->proc_net);
221}
222
223static struct pernet_operations __net_initdata proc_net_ns_ops = {
224	.init = proc_net_ns_init,
225	.exit = proc_net_ns_exit,
226};
227
228int __init proc_net_init(void)
229{
230	proc_symlink("net", NULL, "self/net");
231
232	return register_pernet_subsys(&proc_net_ns_ops);
233}

  1/*
  2 *  linux/fs/proc/net.c
  3 *
  4 *  Copyright (C) 2007
  5 *
  6 *  Author: Eric Biederman <ebiederm@xmission.com>
  7 *
  8 *  proc net directory handling functions
  9 */
 10
 11#include <linux/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/sched/task.h>
 21#include <linux/module.h>
 22#include <linux/bitops.h>
 23#include <linux/mount.h>
 24#include <linux/nsproxy.h>
 25#include <linux/uidgid.h>
 26#include <net/net_namespace.h>
 27#include <linux/seq_file.h>
 28
 29#include "internal.h"
 30
 31static inline struct net *PDE_NET(struct proc_dir_entry *pde)
 32{
 33	return pde->parent->data;
 34}
 35
 36static struct net *get_proc_net(const struct inode *inode)
 37{
 38	return maybe_get_net(PDE_NET(PDE(inode)));
 39}
 40
 41int seq_open_net(struct inode *ino, struct file *f,
 42		 const struct seq_operations *ops, int size)
 43{
 44	struct net *net;
 45	struct seq_net_private *p;
 46
 47	BUG_ON(size < sizeof(*p));
 48
 49	net = get_proc_net(ino);
 50	if (net == NULL)
 51		return -ENXIO;
 52
 53	p = __seq_open_private(f, ops, size);
 54	if (p == NULL) {
 55		put_net(net);
 56		return -ENOMEM;
 57	}
 58#ifdef CONFIG_NET_NS
 59	p->net = net;
 60#endif
 61	return 0;
 62}
 63EXPORT_SYMBOL_GPL(seq_open_net);
 64
 65int single_open_net(struct inode *inode, struct file *file,
 66		int (*show)(struct seq_file *, void *))
 67{
 68	int err;
 69	struct net *net;
 70
 71	err = -ENXIO;
 72	net = get_proc_net(inode);
 73	if (net == NULL)
 74		goto err_net;
 75
 76	err = single_open(file, show, net);
 77	if (err < 0)
 78		goto err_open;
 79
 80	return 0;
 81
 82err_open:
 83	put_net(net);
 84err_net:
 85	return err;
 86}
 87EXPORT_SYMBOL_GPL(single_open_net);
 88
 89int seq_release_net(struct inode *ino, struct file *f)
 90{
 91	struct seq_file *seq;
 92
 93	seq = f->private_data;
 94
 95	put_net(seq_file_net(seq));
 96	seq_release_private(ino, f);
 97	return 0;
 98}
 99EXPORT_SYMBOL_GPL(seq_release_net);
100
101int single_release_net(struct inode *ino, struct file *f)
102{
103	struct seq_file *seq = f->private_data;
104	put_net(seq->private);
105	return single_release(ino, f);
106}
107EXPORT_SYMBOL_GPL(single_release_net);
108
109static struct net *get_proc_task_net(struct inode *dir)
110{
111	struct task_struct *task;
112	struct nsproxy *ns;
113	struct net *net = NULL;
114
115	rcu_read_lock();
116	task = pid_task(proc_pid(dir), PIDTYPE_PID);
117	if (task != NULL) {
118		task_lock(task);
119		ns = task->nsproxy;
120		if (ns != NULL)
121			net = get_net(ns->net_ns);
122		task_unlock(task);
123	}
124	rcu_read_unlock();
125
126	return net;
127}
128
129static struct dentry *proc_tgid_net_lookup(struct inode *dir,
130		struct dentry *dentry, unsigned int flags)
131{
132	struct dentry *de;
133	struct net *net;
134
135	de = ERR_PTR(-ENOENT);
136	net = get_proc_task_net(dir);
137	if (net != NULL) {
138		de = proc_lookup_de(dir, dentry, net->proc_net);
139		put_net(net);
140	}
141	return de;
142}
143
144static int proc_tgid_net_getattr(const struct path *path, struct kstat *stat,
145				 u32 request_mask, unsigned int query_flags)
146{
147	struct inode *inode = d_inode(path->dentry);
148	struct net *net;
149
150	net = get_proc_task_net(inode);
151
152	generic_fillattr(inode, stat);
153
154	if (net != NULL) {
155		stat->nlink = net->proc_net->nlink;
156		put_net(net);
157	}
158
159	return 0;
160}
161
162const struct inode_operations proc_net_inode_operations = {
163	.lookup		= proc_tgid_net_lookup,
164	.getattr	= proc_tgid_net_getattr,
165};
166
167static int proc_tgid_net_readdir(struct file *file, struct dir_context *ctx)
168{
169	int ret;
170	struct net *net;
171
172	ret = -EINVAL;
173	net = get_proc_task_net(file_inode(file));
174	if (net != NULL) {
175		ret = proc_readdir_de(file, ctx, net->proc_net);
176		put_net(net);
177	}
178	return ret;
179}
180
181const struct file_operations proc_net_operations = {
182	.llseek		= generic_file_llseek,
183	.read		= generic_read_dir,
184	.iterate_shared	= proc_tgid_net_readdir,
185};
186
187static __net_init int proc_net_ns_init(struct net *net)
188{
189	struct proc_dir_entry *netd, *net_statd;
190	kuid_t uid;
191	kgid_t gid;
192	int err;
193
194	err = -ENOMEM;
195	netd = kmem_cache_zalloc(proc_dir_entry_cache, GFP_KERNEL);
196	if (!netd)
197		goto out;
198
199	netd->subdir = RB_ROOT;
200	netd->data = net;
201	netd->nlink = 2;
202	netd->namelen = 3;
203	netd->parent = &proc_root;
204	netd->name = netd->inline_name;
205	memcpy(netd->name, "net", 4);
206
207	uid = make_kuid(net->user_ns, 0);
208	if (!uid_valid(uid))
209		uid = netd->uid;
210
211	gid = make_kgid(net->user_ns, 0);
212	if (!gid_valid(gid))
213		gid = netd->gid;
214
215	proc_set_user(netd, uid, gid);
216
217	err = -EEXIST;
218	net_statd = proc_net_mkdir(net, "stat", netd);
219	if (!net_statd)
220		goto free_net;
221
222	net->proc_net = netd;
223	net->proc_net_stat = net_statd;
224	return 0;
225
226free_net:
227	pde_free(netd);
228out:
229	return err;
230}
231
232static __net_exit void proc_net_ns_exit(struct net *net)
233{
234	remove_proc_entry("stat", net->proc_net);
235	pde_free(net->proc_net);
236}
237
238static struct pernet_operations __net_initdata proc_net_ns_ops = {
239	.init = proc_net_ns_init,
240	.exit = proc_net_ns_exit,
241};
242
243int __init proc_net_init(void)
244{
245	proc_symlink("net", NULL, "self/net");
246
247	return register_pernet_subsys(&proc_net_ns_ops);
248}