1 #include <linux/sched.h>
2 #include <linux/errno.h>
3 #include <linux/dcache.h>
4 #include <linux/path.h>
5 #include <linux/fdtable.h>
6 #include <linux/namei.h>
8 #include <linux/security.h>
9 #include <linux/file.h>
10 #include <linux/seq_file.h>
12 #include <linux/proc_fs.h>
17 static int seq_show(struct seq_file
*m
, void *v
)
19 struct files_struct
*files
= NULL
;
20 int f_flags
= 0, ret
= -ENOENT
;
21 struct file
*file
= NULL
;
22 struct task_struct
*task
;
24 task
= get_proc_task(m
->private);
28 files
= get_files_struct(task
);
29 put_task_struct(task
);
32 int fd
= proc_fd(m
->private);
34 spin_lock(&files
->file_lock
);
35 file
= fcheck_files(files
, fd
);
37 struct fdtable
*fdt
= files_fdtable(files
);
39 f_flags
= file
->f_flags
;
40 if (close_on_exec(fd
, fdt
))
46 spin_unlock(&files
->file_lock
);
47 put_files_struct(files
);
51 seq_printf(m
, "pos:\t%lli\nflags:\t0%o\n",
52 (long long)file
->f_pos
, f_flags
);
53 if (file
->f_op
->show_fdinfo
)
54 ret
= file
->f_op
->show_fdinfo(m
, file
);
61 static int seq_fdinfo_open(struct inode
*inode
, struct file
*file
)
63 return single_open(file
, seq_show
, inode
);
66 static const struct file_operations proc_fdinfo_file_operations
= {
67 .open
= seq_fdinfo_open
,
70 .release
= single_release
,
73 static int tid_fd_revalidate(struct dentry
*dentry
, unsigned int flags
)
75 struct files_struct
*files
;
76 struct task_struct
*task
;
77 const struct cred
*cred
;
81 if (flags
& LOOKUP_RCU
)
84 inode
= dentry
->d_inode
;
85 task
= get_proc_task(inode
);
89 files
= get_files_struct(task
);
94 file
= fcheck_files(files
, fd
);
96 unsigned f_mode
= file
->f_mode
;
99 put_files_struct(files
);
101 if (task_dumpable(task
)) {
103 cred
= __task_cred(task
);
104 inode
->i_uid
= cred
->euid
;
105 inode
->i_gid
= cred
->egid
;
108 inode
->i_uid
= GLOBAL_ROOT_UID
;
109 inode
->i_gid
= GLOBAL_ROOT_GID
;
112 if (S_ISLNK(inode
->i_mode
)) {
113 unsigned i_mode
= S_IFLNK
;
114 if (f_mode
& FMODE_READ
)
115 i_mode
|= S_IRUSR
| S_IXUSR
;
116 if (f_mode
& FMODE_WRITE
)
117 i_mode
|= S_IWUSR
| S_IXUSR
;
118 inode
->i_mode
= i_mode
;
121 security_task_to_inode(task
, inode
);
122 put_task_struct(task
);
126 put_files_struct(files
);
128 put_task_struct(task
);
135 static const struct dentry_operations tid_fd_dentry_operations
= {
136 .d_revalidate
= tid_fd_revalidate
,
137 .d_delete
= pid_delete_dentry
,
140 static int proc_fd_link(struct dentry
*dentry
, struct path
*path
)
142 struct files_struct
*files
= NULL
;
143 struct task_struct
*task
;
146 task
= get_proc_task(dentry
->d_inode
);
148 files
= get_files_struct(task
);
149 put_task_struct(task
);
153 int fd
= proc_fd(dentry
->d_inode
);
154 struct file
*fd_file
;
156 spin_lock(&files
->file_lock
);
157 fd_file
= fcheck_files(files
, fd
);
159 *path
= fd_file
->f_path
;
160 path_get(&fd_file
->f_path
);
163 spin_unlock(&files
->file_lock
);
164 put_files_struct(files
);
171 proc_fd_instantiate(struct inode
*dir
, struct dentry
*dentry
,
172 struct task_struct
*task
, const void *ptr
)
174 unsigned fd
= (unsigned long)ptr
;
175 struct proc_inode
*ei
;
178 inode
= proc_pid_make_inode(dir
->i_sb
, task
);
185 inode
->i_mode
= S_IFLNK
;
186 inode
->i_op
= &proc_pid_link_inode_operations
;
189 ei
->op
.proc_get_link
= proc_fd_link
;
191 d_set_d_op(dentry
, &tid_fd_dentry_operations
);
192 d_add(dentry
, inode
);
194 /* Close the race of the process dying before we return the dentry */
195 if (tid_fd_revalidate(dentry
, 0))
201 static struct dentry
*proc_lookupfd_common(struct inode
*dir
,
202 struct dentry
*dentry
,
203 instantiate_t instantiate
)
205 struct task_struct
*task
= get_proc_task(dir
);
206 int result
= -ENOENT
;
207 unsigned fd
= name_to_int(dentry
);
214 result
= instantiate(dir
, dentry
, task
, (void *)(unsigned long)fd
);
216 put_task_struct(task
);
218 return ERR_PTR(result
);
221 static int proc_readfd_common(struct file
*file
, struct dir_context
*ctx
,
222 instantiate_t instantiate
)
224 struct task_struct
*p
= get_proc_task(file_inode(file
));
225 struct files_struct
*files
;
231 if (!dir_emit_dots(file
, ctx
))
233 if (!dir_emit_dots(file
, ctx
))
235 files
= get_files_struct(p
);
240 for (fd
= ctx
->pos
- 2;
241 fd
< files_fdtable(files
)->max_fds
;
243 char name
[PROC_NUMBUF
];
246 if (!fcheck_files(files
, fd
))
250 len
= snprintf(name
, sizeof(name
), "%d", fd
);
251 if (!proc_fill_cache(file
, ctx
,
252 name
, len
, instantiate
, p
,
253 (void *)(unsigned long)fd
))
259 put_files_struct(files
);
265 static int proc_readfd(struct file
*file
, struct dir_context
*ctx
)
267 return proc_readfd_common(file
, ctx
, proc_fd_instantiate
);
270 const struct file_operations proc_fd_operations
= {
271 .read
= generic_read_dir
,
272 .iterate
= proc_readfd
,
273 .llseek
= default_llseek
,
276 static struct dentry
*proc_lookupfd(struct inode
*dir
, struct dentry
*dentry
,
279 return proc_lookupfd_common(dir
, dentry
, proc_fd_instantiate
);
283 * /proc/pid/fd needs a special permission handler so that a process can still
284 * access /proc/self/fd after it has executed a setuid().
286 int proc_fd_permission(struct inode
*inode
, int mask
)
288 int rv
= generic_permission(inode
, mask
);
291 if (task_pid(current
) == proc_pid(inode
))
296 const struct inode_operations proc_fd_inode_operations
= {
297 .lookup
= proc_lookupfd
,
298 .permission
= proc_fd_permission
,
299 .setattr
= proc_setattr
,
303 proc_fdinfo_instantiate(struct inode
*dir
, struct dentry
*dentry
,
304 struct task_struct
*task
, const void *ptr
)
306 unsigned fd
= (unsigned long)ptr
;
307 struct proc_inode
*ei
;
310 inode
= proc_pid_make_inode(dir
->i_sb
, task
);
317 inode
->i_mode
= S_IFREG
| S_IRUSR
;
318 inode
->i_fop
= &proc_fdinfo_file_operations
;
320 d_set_d_op(dentry
, &tid_fd_dentry_operations
);
321 d_add(dentry
, inode
);
323 /* Close the race of the process dying before we return the dentry */
324 if (tid_fd_revalidate(dentry
, 0))
330 static struct dentry
*
331 proc_lookupfdinfo(struct inode
*dir
, struct dentry
*dentry
, unsigned int flags
)
333 return proc_lookupfd_common(dir
, dentry
, proc_fdinfo_instantiate
);
336 static int proc_readfdinfo(struct file
*file
, struct dir_context
*ctx
)
338 return proc_readfd_common(file
, ctx
,
339 proc_fdinfo_instantiate
);
342 const struct inode_operations proc_fdinfo_inode_operations
= {
343 .lookup
= proc_lookupfdinfo
,
344 .setattr
= proc_setattr
,
347 const struct file_operations proc_fdinfo_operations
= {
348 .read
= generic_read_dir
,
349 .iterate
= proc_readfdinfo
,
350 .llseek
= default_llseek
,