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v3.1
  1#include <linux/proc_fs.h>
  2#include <linux/nsproxy.h>
  3#include <linux/sched.h>
  4#include <linux/ptrace.h>
  5#include <linux/fs_struct.h>
  6#include <linux/mount.h>
  7#include <linux/path.h>
  8#include <linux/namei.h>
  9#include <linux/file.h>
 10#include <linux/utsname.h>
 11#include <net/net_namespace.h>
 12#include <linux/mnt_namespace.h>
 13#include <linux/ipc_namespace.h>
 14#include <linux/pid_namespace.h>
 15#include "internal.h"
 16
 17
 18static const struct proc_ns_operations *ns_entries[] = {
 19#ifdef CONFIG_NET_NS
 20	&netns_operations,
 21#endif
 22#ifdef CONFIG_UTS_NS
 23	&utsns_operations,
 24#endif
 25#ifdef CONFIG_IPC_NS
 26	&ipcns_operations,
 27#endif
 28};
 29
 30static const struct file_operations ns_file_operations = {
 31	.llseek		= no_llseek,
 32};
 33
 34static struct dentry *proc_ns_instantiate(struct inode *dir,
 35	struct dentry *dentry, struct task_struct *task, const void *ptr)
 36{
 37	const struct proc_ns_operations *ns_ops = ptr;
 38	struct inode *inode;
 39	struct proc_inode *ei;
 40	struct dentry *error = ERR_PTR(-ENOENT);
 41	void *ns;
 42
 43	inode = proc_pid_make_inode(dir->i_sb, task);
 44	if (!inode)
 45		goto out;
 46
 47	ns = ns_ops->get(task);
 48	if (!ns)
 49		goto out_iput;
 50
 51	ei = PROC_I(inode);
 52	inode->i_mode = S_IFREG|S_IRUSR;
 53	inode->i_fop  = &ns_file_operations;
 54	ei->ns_ops    = ns_ops;
 55	ei->ns	      = ns;
 56
 57	dentry->d_op = &pid_dentry_operations;
 58	d_add(dentry, inode);
 59	/* Close the race of the process dying before we return the dentry */
 60	if (pid_revalidate(dentry, NULL))
 61		error = NULL;
 62out:
 63	return error;
 64out_iput:
 65	iput(inode);
 66	goto out;
 67}
 68
 69static int proc_ns_fill_cache(struct file *filp, void *dirent,
 70	filldir_t filldir, struct task_struct *task,
 71	const struct proc_ns_operations *ops)
 72{
 73	return proc_fill_cache(filp, dirent, filldir,
 74				ops->name, strlen(ops->name),
 75				proc_ns_instantiate, task, ops);
 76}
 77
 78static int proc_ns_dir_readdir(struct file *filp, void *dirent,
 79				filldir_t filldir)
 80{
 81	int i;
 82	struct dentry *dentry = filp->f_path.dentry;
 83	struct inode *inode = dentry->d_inode;
 84	struct task_struct *task = get_proc_task(inode);
 85	const struct proc_ns_operations **entry, **last;
 86	ino_t ino;
 87	int ret;
 88
 89	ret = -ENOENT;
 90	if (!task)
 91		goto out_no_task;
 92
 93	ret = -EPERM;
 94	if (!ptrace_may_access(task, PTRACE_MODE_READ))
 95		goto out;
 96
 97	ret = 0;
 98	i = filp->f_pos;
 99	switch (i) {
100	case 0:
101		ino = inode->i_ino;
102		if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
103			goto out;
104		i++;
105		filp->f_pos++;
106		/* fall through */
107	case 1:
108		ino = parent_ino(dentry);
109		if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
110			goto out;
111		i++;
112		filp->f_pos++;
113		/* fall through */
114	default:
115		i -= 2;
116		if (i >= ARRAY_SIZE(ns_entries)) {
117			ret = 1;
118			goto out;
119		}
120		entry = ns_entries + i;
121		last = &ns_entries[ARRAY_SIZE(ns_entries) - 1];
122		while (entry <= last) {
123			if (proc_ns_fill_cache(filp, dirent, filldir,
124						task, *entry) < 0)
125				goto out;
126			filp->f_pos++;
127			entry++;
128		}
129	}
130
131	ret = 1;
132out:
133	put_task_struct(task);
134out_no_task:
135	return ret;
136}
137
138const struct file_operations proc_ns_dir_operations = {
139	.read		= generic_read_dir,
140	.readdir	= proc_ns_dir_readdir,
141};
142
143static struct dentry *proc_ns_dir_lookup(struct inode *dir,
144				struct dentry *dentry, struct nameidata *nd)
145{
146	struct dentry *error;
147	struct task_struct *task = get_proc_task(dir);
148	const struct proc_ns_operations **entry, **last;
149	unsigned int len = dentry->d_name.len;
150
151	error = ERR_PTR(-ENOENT);
152
153	if (!task)
154		goto out_no_task;
155
156	error = ERR_PTR(-EPERM);
157	if (!ptrace_may_access(task, PTRACE_MODE_READ))
158		goto out;
159
160	last = &ns_entries[ARRAY_SIZE(ns_entries) - 1];
161	for (entry = ns_entries; entry <= last; entry++) {
162		if (strlen((*entry)->name) != len)
163			continue;
164		if (!memcmp(dentry->d_name.name, (*entry)->name, len))
165			break;
166	}
167	error = ERR_PTR(-ENOENT);
168	if (entry > last)
169		goto out;
170
171	error = proc_ns_instantiate(dir, dentry, task, *entry);
172out:
173	put_task_struct(task);
174out_no_task:
175	return error;
176}
177
178const struct inode_operations proc_ns_dir_inode_operations = {
179	.lookup		= proc_ns_dir_lookup,
180	.getattr	= pid_getattr,
181	.setattr	= proc_setattr,
182};
183
184struct file *proc_ns_fget(int fd)
185{
186	struct file *file;
187
188	file = fget(fd);
189	if (!file)
190		return ERR_PTR(-EBADF);
191
192	if (file->f_op != &ns_file_operations)
193		goto out_invalid;
194
195	return file;
196
197out_invalid:
198	fput(file);
199	return ERR_PTR(-EINVAL);
200}
201
v3.5.6
  1#include <linux/proc_fs.h>
  2#include <linux/nsproxy.h>
  3#include <linux/sched.h>
  4#include <linux/ptrace.h>
  5#include <linux/fs_struct.h>
  6#include <linux/mount.h>
  7#include <linux/path.h>
  8#include <linux/namei.h>
  9#include <linux/file.h>
 10#include <linux/utsname.h>
 11#include <net/net_namespace.h>
 
 12#include <linux/ipc_namespace.h>
 13#include <linux/pid_namespace.h>
 14#include "internal.h"
 15
 16
 17static const struct proc_ns_operations *ns_entries[] = {
 18#ifdef CONFIG_NET_NS
 19	&netns_operations,
 20#endif
 21#ifdef CONFIG_UTS_NS
 22	&utsns_operations,
 23#endif
 24#ifdef CONFIG_IPC_NS
 25	&ipcns_operations,
 26#endif
 27};
 28
 29static const struct file_operations ns_file_operations = {
 30	.llseek		= no_llseek,
 31};
 32
 33static struct dentry *proc_ns_instantiate(struct inode *dir,
 34	struct dentry *dentry, struct task_struct *task, const void *ptr)
 35{
 36	const struct proc_ns_operations *ns_ops = ptr;
 37	struct inode *inode;
 38	struct proc_inode *ei;
 39	struct dentry *error = ERR_PTR(-ENOENT);
 40	void *ns;
 41
 42	inode = proc_pid_make_inode(dir->i_sb, task);
 43	if (!inode)
 44		goto out;
 45
 46	ns = ns_ops->get(task);
 47	if (!ns)
 48		goto out_iput;
 49
 50	ei = PROC_I(inode);
 51	inode->i_mode = S_IFREG|S_IRUSR;
 52	inode->i_fop  = &ns_file_operations;
 53	ei->ns_ops    = ns_ops;
 54	ei->ns	      = ns;
 55
 56	d_set_d_op(dentry, &pid_dentry_operations);
 57	d_add(dentry, inode);
 58	/* Close the race of the process dying before we return the dentry */
 59	if (pid_revalidate(dentry, NULL))
 60		error = NULL;
 61out:
 62	return error;
 63out_iput:
 64	iput(inode);
 65	goto out;
 66}
 67
 68static int proc_ns_fill_cache(struct file *filp, void *dirent,
 69	filldir_t filldir, struct task_struct *task,
 70	const struct proc_ns_operations *ops)
 71{
 72	return proc_fill_cache(filp, dirent, filldir,
 73				ops->name, strlen(ops->name),
 74				proc_ns_instantiate, task, ops);
 75}
 76
 77static int proc_ns_dir_readdir(struct file *filp, void *dirent,
 78				filldir_t filldir)
 79{
 80	int i;
 81	struct dentry *dentry = filp->f_path.dentry;
 82	struct inode *inode = dentry->d_inode;
 83	struct task_struct *task = get_proc_task(inode);
 84	const struct proc_ns_operations **entry, **last;
 85	ino_t ino;
 86	int ret;
 87
 88	ret = -ENOENT;
 89	if (!task)
 90		goto out_no_task;
 91
 92	ret = -EPERM;
 93	if (!ptrace_may_access(task, PTRACE_MODE_READ))
 94		goto out;
 95
 96	ret = 0;
 97	i = filp->f_pos;
 98	switch (i) {
 99	case 0:
100		ino = inode->i_ino;
101		if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
102			goto out;
103		i++;
104		filp->f_pos++;
105		/* fall through */
106	case 1:
107		ino = parent_ino(dentry);
108		if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
109			goto out;
110		i++;
111		filp->f_pos++;
112		/* fall through */
113	default:
114		i -= 2;
115		if (i >= ARRAY_SIZE(ns_entries)) {
116			ret = 1;
117			goto out;
118		}
119		entry = ns_entries + i;
120		last = &ns_entries[ARRAY_SIZE(ns_entries) - 1];
121		while (entry <= last) {
122			if (proc_ns_fill_cache(filp, dirent, filldir,
123						task, *entry) < 0)
124				goto out;
125			filp->f_pos++;
126			entry++;
127		}
128	}
129
130	ret = 1;
131out:
132	put_task_struct(task);
133out_no_task:
134	return ret;
135}
136
137const struct file_operations proc_ns_dir_operations = {
138	.read		= generic_read_dir,
139	.readdir	= proc_ns_dir_readdir,
140};
141
142static struct dentry *proc_ns_dir_lookup(struct inode *dir,
143				struct dentry *dentry, struct nameidata *nd)
144{
145	struct dentry *error;
146	struct task_struct *task = get_proc_task(dir);
147	const struct proc_ns_operations **entry, **last;
148	unsigned int len = dentry->d_name.len;
149
150	error = ERR_PTR(-ENOENT);
151
152	if (!task)
153		goto out_no_task;
154
155	error = ERR_PTR(-EPERM);
156	if (!ptrace_may_access(task, PTRACE_MODE_READ))
157		goto out;
158
159	last = &ns_entries[ARRAY_SIZE(ns_entries)];
160	for (entry = ns_entries; entry < last; entry++) {
161		if (strlen((*entry)->name) != len)
162			continue;
163		if (!memcmp(dentry->d_name.name, (*entry)->name, len))
164			break;
165	}
166	error = ERR_PTR(-ENOENT);
167	if (entry == last)
168		goto out;
169
170	error = proc_ns_instantiate(dir, dentry, task, *entry);
171out:
172	put_task_struct(task);
173out_no_task:
174	return error;
175}
176
177const struct inode_operations proc_ns_dir_inode_operations = {
178	.lookup		= proc_ns_dir_lookup,
179	.getattr	= pid_getattr,
180	.setattr	= proc_setattr,
181};
182
183struct file *proc_ns_fget(int fd)
184{
185	struct file *file;
186
187	file = fget(fd);
188	if (!file)
189		return ERR_PTR(-EBADF);
190
191	if (file->f_op != &ns_file_operations)
192		goto out_invalid;
193
194	return file;
195
196out_invalid:
197	fput(file);
198	return ERR_PTR(-EINVAL);
199}
200