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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};
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