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v4.6
  1#include <linux/proc_fs.h>
  2#include <linux/nsproxy.h>
  3#include <linux/ptrace.h>
  4#include <linux/namei.h>
  5#include <linux/file.h>
  6#include <linux/utsname.h>
  7#include <net/net_namespace.h>
  8#include <linux/ipc_namespace.h>
  9#include <linux/pid_namespace.h>
 10#include <linux/user_namespace.h>
 11#include "internal.h"
 12
 13
 14static const struct proc_ns_operations *ns_entries[] = {
 15#ifdef CONFIG_NET_NS
 16	&netns_operations,
 17#endif
 18#ifdef CONFIG_UTS_NS
 19	&utsns_operations,
 20#endif
 21#ifdef CONFIG_IPC_NS
 22	&ipcns_operations,
 23#endif
 24#ifdef CONFIG_PID_NS
 25	&pidns_operations,
 26#endif
 27#ifdef CONFIG_USER_NS
 28	&userns_operations,
 29#endif
 30	&mntns_operations,
 31#ifdef CONFIG_CGROUPS
 32	&cgroupns_operations,
 33#endif
 34};
 35
 36static const char *proc_ns_get_link(struct dentry *dentry,
 37				    struct inode *inode,
 38				    struct delayed_call *done)
 39{
 40	const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
 41	struct task_struct *task;
 42	struct path ns_path;
 43	void *error = ERR_PTR(-EACCES);
 44
 45	if (!dentry)
 46		return ERR_PTR(-ECHILD);
 47
 48	task = get_proc_task(inode);
 49	if (!task)
 50		return error;
 51
 52	if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
 53		error = ns_get_path(&ns_path, task, ns_ops);
 54		if (!error)
 55			nd_jump_link(&ns_path);
 56	}
 57	put_task_struct(task);
 58	return error;
 59}
 60
 61static int proc_ns_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 62{
 63	struct inode *inode = d_inode(dentry);
 64	const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
 65	struct task_struct *task;
 66	char name[50];
 67	int res = -EACCES;
 68
 69	task = get_proc_task(inode);
 70	if (!task)
 71		return res;
 72
 73	if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
 74		res = ns_get_name(name, sizeof(name), task, ns_ops);
 75		if (res >= 0)
 76			res = readlink_copy(buffer, buflen, name);
 77	}
 78	put_task_struct(task);
 79	return res;
 80}
 81
 82static const struct inode_operations proc_ns_link_inode_operations = {
 83	.readlink	= proc_ns_readlink,
 84	.get_link	= proc_ns_get_link,
 85	.setattr	= proc_setattr,
 86};
 87
 88static int proc_ns_instantiate(struct inode *dir,
 89	struct dentry *dentry, struct task_struct *task, const void *ptr)
 90{
 91	const struct proc_ns_operations *ns_ops = ptr;
 92	struct inode *inode;
 93	struct proc_inode *ei;
 94
 95	inode = proc_pid_make_inode(dir->i_sb, task);
 96	if (!inode)
 97		goto out;
 98
 99	ei = PROC_I(inode);
100	inode->i_mode = S_IFLNK|S_IRWXUGO;
101	inode->i_op = &proc_ns_link_inode_operations;
102	ei->ns_ops = ns_ops;
103
104	d_set_d_op(dentry, &pid_dentry_operations);
105	d_add(dentry, inode);
106	/* Close the race of the process dying before we return the dentry */
107	if (pid_revalidate(dentry, 0))
108		return 0;
109out:
110	return -ENOENT;
111}
112
113static int proc_ns_dir_readdir(struct file *file, struct dir_context *ctx)
114{
115	struct task_struct *task = get_proc_task(file_inode(file));
116	const struct proc_ns_operations **entry, **last;
117
118	if (!task)
119		return -ENOENT;
120
121	if (!dir_emit_dots(file, ctx))
122		goto out;
123	if (ctx->pos >= 2 + ARRAY_SIZE(ns_entries))
124		goto out;
125	entry = ns_entries + (ctx->pos - 2);
126	last = &ns_entries[ARRAY_SIZE(ns_entries) - 1];
127	while (entry <= last) {
128		const struct proc_ns_operations *ops = *entry;
129		if (!proc_fill_cache(file, ctx, ops->name, strlen(ops->name),
130				     proc_ns_instantiate, task, ops))
131			break;
132		ctx->pos++;
133		entry++;
134	}
135out:
136	put_task_struct(task);
137	return 0;
138}
139
140const struct file_operations proc_ns_dir_operations = {
141	.read		= generic_read_dir,
142	.iterate	= proc_ns_dir_readdir,
 
143};
144
145static struct dentry *proc_ns_dir_lookup(struct inode *dir,
146				struct dentry *dentry, unsigned int flags)
147{
148	int error;
149	struct task_struct *task = get_proc_task(dir);
150	const struct proc_ns_operations **entry, **last;
151	unsigned int len = dentry->d_name.len;
152
153	error = -ENOENT;
154
155	if (!task)
156		goto out_no_task;
157
158	last = &ns_entries[ARRAY_SIZE(ns_entries)];
159	for (entry = ns_entries; entry < last; entry++) {
160		if (strlen((*entry)->name) != len)
161			continue;
162		if (!memcmp(dentry->d_name.name, (*entry)->name, len))
163			break;
164	}
165	if (entry == last)
166		goto out;
167
168	error = proc_ns_instantiate(dir, dentry, task, *entry);
169out:
170	put_task_struct(task);
171out_no_task:
172	return ERR_PTR(error);
173}
174
175const struct inode_operations proc_ns_dir_inode_operations = {
176	.lookup		= proc_ns_dir_lookup,
177	.getattr	= pid_getattr,
178	.setattr	= proc_setattr,
179};
v4.10.11
  1#include <linux/proc_fs.h>
  2#include <linux/nsproxy.h>
  3#include <linux/ptrace.h>
  4#include <linux/namei.h>
  5#include <linux/file.h>
  6#include <linux/utsname.h>
  7#include <net/net_namespace.h>
  8#include <linux/ipc_namespace.h>
  9#include <linux/pid_namespace.h>
 10#include <linux/user_namespace.h>
 11#include "internal.h"
 12
 13
 14static const struct proc_ns_operations *ns_entries[] = {
 15#ifdef CONFIG_NET_NS
 16	&netns_operations,
 17#endif
 18#ifdef CONFIG_UTS_NS
 19	&utsns_operations,
 20#endif
 21#ifdef CONFIG_IPC_NS
 22	&ipcns_operations,
 23#endif
 24#ifdef CONFIG_PID_NS
 25	&pidns_operations,
 26#endif
 27#ifdef CONFIG_USER_NS
 28	&userns_operations,
 29#endif
 30	&mntns_operations,
 31#ifdef CONFIG_CGROUPS
 32	&cgroupns_operations,
 33#endif
 34};
 35
 36static const char *proc_ns_get_link(struct dentry *dentry,
 37				    struct inode *inode,
 38				    struct delayed_call *done)
 39{
 40	const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
 41	struct task_struct *task;
 42	struct path ns_path;
 43	void *error = ERR_PTR(-EACCES);
 44
 45	if (!dentry)
 46		return ERR_PTR(-ECHILD);
 47
 48	task = get_proc_task(inode);
 49	if (!task)
 50		return error;
 51
 52	if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
 53		error = ns_get_path(&ns_path, task, ns_ops);
 54		if (!error)
 55			nd_jump_link(&ns_path);
 56	}
 57	put_task_struct(task);
 58	return error;
 59}
 60
 61static int proc_ns_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 62{
 63	struct inode *inode = d_inode(dentry);
 64	const struct proc_ns_operations *ns_ops = PROC_I(inode)->ns_ops;
 65	struct task_struct *task;
 66	char name[50];
 67	int res = -EACCES;
 68
 69	task = get_proc_task(inode);
 70	if (!task)
 71		return res;
 72
 73	if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
 74		res = ns_get_name(name, sizeof(name), task, ns_ops);
 75		if (res >= 0)
 76			res = readlink_copy(buffer, buflen, name);
 77	}
 78	put_task_struct(task);
 79	return res;
 80}
 81
 82static const struct inode_operations proc_ns_link_inode_operations = {
 83	.readlink	= proc_ns_readlink,
 84	.get_link	= proc_ns_get_link,
 85	.setattr	= proc_setattr,
 86};
 87
 88static int proc_ns_instantiate(struct inode *dir,
 89	struct dentry *dentry, struct task_struct *task, const void *ptr)
 90{
 91	const struct proc_ns_operations *ns_ops = ptr;
 92	struct inode *inode;
 93	struct proc_inode *ei;
 94
 95	inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK | S_IRWXUGO);
 96	if (!inode)
 97		goto out;
 98
 99	ei = PROC_I(inode);
 
100	inode->i_op = &proc_ns_link_inode_operations;
101	ei->ns_ops = ns_ops;
102
103	d_set_d_op(dentry, &pid_dentry_operations);
104	d_add(dentry, inode);
105	/* Close the race of the process dying before we return the dentry */
106	if (pid_revalidate(dentry, 0))
107		return 0;
108out:
109	return -ENOENT;
110}
111
112static int proc_ns_dir_readdir(struct file *file, struct dir_context *ctx)
113{
114	struct task_struct *task = get_proc_task(file_inode(file));
115	const struct proc_ns_operations **entry, **last;
116
117	if (!task)
118		return -ENOENT;
119
120	if (!dir_emit_dots(file, ctx))
121		goto out;
122	if (ctx->pos >= 2 + ARRAY_SIZE(ns_entries))
123		goto out;
124	entry = ns_entries + (ctx->pos - 2);
125	last = &ns_entries[ARRAY_SIZE(ns_entries) - 1];
126	while (entry <= last) {
127		const struct proc_ns_operations *ops = *entry;
128		if (!proc_fill_cache(file, ctx, ops->name, strlen(ops->name),
129				     proc_ns_instantiate, task, ops))
130			break;
131		ctx->pos++;
132		entry++;
133	}
134out:
135	put_task_struct(task);
136	return 0;
137}
138
139const struct file_operations proc_ns_dir_operations = {
140	.read		= generic_read_dir,
141	.iterate_shared	= proc_ns_dir_readdir,
142	.llseek		= generic_file_llseek,
143};
144
145static struct dentry *proc_ns_dir_lookup(struct inode *dir,
146				struct dentry *dentry, unsigned int flags)
147{
148	int error;
149	struct task_struct *task = get_proc_task(dir);
150	const struct proc_ns_operations **entry, **last;
151	unsigned int len = dentry->d_name.len;
152
153	error = -ENOENT;
154
155	if (!task)
156		goto out_no_task;
157
158	last = &ns_entries[ARRAY_SIZE(ns_entries)];
159	for (entry = ns_entries; entry < last; entry++) {
160		if (strlen((*entry)->name) != len)
161			continue;
162		if (!memcmp(dentry->d_name.name, (*entry)->name, len))
163			break;
164	}
165	if (entry == last)
166		goto out;
167
168	error = proc_ns_instantiate(dir, dentry, task, *entry);
169out:
170	put_task_struct(task);
171out_no_task:
172	return ERR_PTR(error);
173}
174
175const struct inode_operations proc_ns_dir_inode_operations = {
176	.lookup		= proc_ns_dir_lookup,
177	.getattr	= pid_getattr,
178	.setattr	= proc_setattr,
179};