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report errors in /proc/*/*map* sanely
[people/ms/linux.git] / fs / proc / base.c
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1da177e4
LT		 1/*
2 * linux/fs/proc/base.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * proc base directory handling functions
7 *
8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
9 * Instead of using magical inumbers to determine the kind of object
10 * we allocate and fill in-core inodes upon lookup. They don't even
11 * go into icache. We cache the reference to task_struct upon lookup too.
12 * Eventually it should become a filesystem in its own. We don't use the
13 * rest of procfs anymore.
e070ad49
ML		 14 *
15 *
16 * Changelog:
17 * 17-Jan-2005
18 * Allan Bezerra
19 * Bruna Moreira <bruna.moreira@indt.org.br>
20 * Edjard Mota <edjard.mota@indt.org.br>
21 * Ilias Biris <ilias.biris@indt.org.br>
22 * Mauricio Lin <mauricio.lin@indt.org.br>
23 *
24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
25 *
26 * A new process specific entry (smaps) included in /proc. It shows the
27 * size of rss for each memory area. The maps entry lacks information
28 * about physical memory size (rss) for each mapped file, i.e.,
29 * rss information for executables and library files.
30 * This additional information is useful for any tools that need to know
31 * about physical memory consumption for a process specific library.
32 *
33 * Changelog:
34 * 21-Feb-2005
35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
36 * Pud inclusion in the page table walking.
37 *
38 * ChangeLog:
39 * 10-Mar-2005
40 * 10LE Instituto Nokia de Tecnologia - INdT:
41 * A better way to walks through the page table as suggested by Hugh Dickins.
42 *
43 * Simo Piiroinen <simo.piiroinen@nokia.com>:
44 * Smaps information related to shared, private, clean and dirty pages.
45 *
46 * Paul Mundt <paul.mundt@nokia.com>:
47 * Overall revision about smaps.
1da177e4
LT		 48 */
49
50#include <asm/uaccess.h>
51
1da177e4
LT		 52#include <linux/errno.h>
53#include <linux/time.h>
54#include <linux/proc_fs.h>
55#include <linux/stat.h>
5995477a 56#include <linux/task_io_accounting_ops.h>
1da177e4 57#include <linux/init.h>
16f7e0fe 58#include <linux/capability.h>
1da177e4 59#include <linux/file.h>
9f3acc31 60#include <linux/fdtable.h>
1da177e4
LT		 61#include <linux/string.h>
62#include <linux/seq_file.h>
63#include <linux/namei.h>
6b3286ed 64#include <linux/mnt_namespace.h>
1da177e4 65#include <linux/mm.h>
a63d83f4 66#include <linux/swap.h>
b835996f 67#include <linux/rcupdate.h>
1da177e4 68#include <linux/kallsyms.h>
2ec220e2 69#include <linux/stacktrace.h>
d85f50d5 70#include <linux/resource.h>
5096add8 71#include <linux/module.h>
1da177e4
LT		 72#include <linux/mount.h>
73#include <linux/security.h>
74#include <linux/ptrace.h>
0d094efe 75#include <linux/tracehook.h>
a424316c 76#include <linux/cgroup.h>
1da177e4
LT		 77#include <linux/cpuset.h>
78#include <linux/audit.h>
5addc5dd 79#include <linux/poll.h>
1651e14e 80#include <linux/nsproxy.h>
8ac773b4 81#include <linux/oom.h>
3cb4a0bb 82#include <linux/elf.h>
60347f67 83#include <linux/pid_namespace.h>
5ad4e53b 84#include <linux/fs_struct.h>
5a0e3ad6 85#include <linux/slab.h>
1da177e4
LT		 86#include "internal.h"
87
0f2fe20f
EB		 88/* NOTE:
89 * Implementing inode permission operations in /proc is almost
90 * certainly an error. Permission checks need to happen during
91 * each system call not at open time. The reason is that most of
92 * what we wish to check for permissions in /proc varies at runtime.
93 *
94 * The classic example of a problem is opening file descriptors
95 * in /proc for a task before it execs a suid executable.
96 */
97
1da177e4 98struct pid_entry {
1da177e4 99 char *name;
c5141e6d 100 int len;
1da177e4 101 mode_t mode;
c5ef1c42 102 const struct inode_operations *iop;
00977a59 103 const struct file_operations *fop;
20cdc894 104 union proc_op op;
1da177e4
LT		 105};
106
61a28784 107#define NOD(NAME, MODE, IOP, FOP, OP) { \
20cdc894 108 .name = (NAME), \
c5141e6d 109 .len = sizeof(NAME) - 1, \
20cdc894
EB		 110 .mode = MODE, \
111 .iop = IOP, \
112 .fop = FOP, \
113 .op = OP, \
114}
115
631f9c18
AD		 116#define DIR(NAME, MODE, iops, fops) \
117 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
118#define LNK(NAME, get_link) \
61a28784 119 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
20cdc894 120 &proc_pid_link_inode_operations, NULL, \
631f9c18
AD		 121 { .proc_get_link = get_link } )
122#define REG(NAME, MODE, fops) \
123 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
124#define INF(NAME, MODE, read) \
61a28784 125 NOD(NAME, (S_IFREG|(MODE)), \
20cdc894 126 NULL, &proc_info_file_operations, \
631f9c18
AD		 127 { .proc_read = read } )
128#define ONE(NAME, MODE, show) \
be614086
EB		 129 NOD(NAME, (S_IFREG|(MODE)), \
130 NULL, &proc_single_file_operations, \
631f9c18 131 { .proc_show = show } )
1da177e4 132
aed54175
VN		 133/*
134 * Count the number of hardlinks for the pid_entry table, excluding the .
135 * and .. links.
136 */
137static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
138 unsigned int n)
139{
140 unsigned int i;
141 unsigned int count;
142
143 count = 0;
144 for (i = 0; i < n; ++i) {
145 if (S_ISDIR(entries[i].mode))
146 ++count;
147 }
148
149 return count;
150}
151
f7ad3c6b 152static int get_task_root(struct task_struct *task, struct path *root)
1da177e4 153{
7c2c7d99
HD		 154 int result = -ENOENT;
155
0494f6ec 156 task_lock(task);
f7ad3c6b
MS		 157 if (task->fs) {
158 get_fs_root(task->fs, root);
7c2c7d99
HD		 159 result = 0;
160 }
0494f6ec 161 task_unlock(task);
7c2c7d99 162 return result;
0494f6ec
MS		 163}
164
3dcd25f3 165static int proc_cwd_link(struct inode *inode, struct path *path)
0494f6ec 166{
99f89551 167 struct task_struct *task = get_proc_task(inode);
0494f6ec 168 int result = -ENOENT;
99f89551
EB		 169
170 if (task) {
f7ad3c6b
MS		 171 task_lock(task);
172 if (task->fs) {
173 get_fs_pwd(task->fs, path);
174 result = 0;
175 }
176 task_unlock(task);
99f89551
EB		 177 put_task_struct(task);
178 }
1da177e4
LT		 179 return result;
180}
181
3dcd25f3 182static int proc_root_link(struct inode *inode, struct path *path)
1da177e4 183{
99f89551 184 struct task_struct *task = get_proc_task(inode);
1da177e4 185 int result = -ENOENT;
99f89551
EB		 186
187 if (task) {
f7ad3c6b 188 result = get_task_root(task, path);
99f89551
EB		 189 put_task_struct(task);
190 }
1da177e4
LT		 191 return result;
192}
193
638fa202
RM		 194/*
195 * Return zero if current may access user memory in @task, -error if not.
196 */
197static int check_mem_permission(struct task_struct *task)
198{
199 /*
200 * A task can always look at itself, in case it chooses
201 * to use system calls instead of load instructions.
202 */
203 if (task == current)
204 return 0;
205
206 /*
207 * If current is actively ptrace'ing, and would also be
208 * permitted to freshly attach with ptrace now, permit it.
209 */
0d094efe
RM		 210 if (task_is_stopped_or_traced(task)) {
211 int match;
212 rcu_read_lock();
213 match = (tracehook_tracer_task(task) == current);
214 rcu_read_unlock();
215 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
216 return 0;
217 }
638fa202
RM		 218
219 /*
220 * Noone else is allowed.
221 */
222 return -EPERM;
223}
1da177e4 224
831830b5
AV		 225struct mm_struct *mm_for_maps(struct task_struct *task)
226{
704b836c 227 struct mm_struct *mm;
ec6fd8a4 228 int err;
704b836c 229
ec6fd8a4
AV		 230 err = mutex_lock_killable(&task->signal->cred_guard_mutex);
231 if (err)
232 return ERR_PTR(err);
00f89d21 233
704b836c
ON		 234 mm = get_task_mm(task);
235 if (mm && mm != current->mm &&
236 !ptrace_may_access(task, PTRACE_MODE_READ)) {
237 mmput(mm);
ec6fd8a4 238 mm = ERR_PTR(-EACCES);
13f0feaf 239 }
9b1bf12d 240 mutex_unlock(&task->signal->cred_guard_mutex);
704b836c 241
831830b5 242 return mm;
831830b5
AV		 243}
244
1da177e4
LT		 245static int proc_pid_cmdline(struct task_struct *task, char * buffer)
246{
247 int res = 0;
248 unsigned int len;
249 struct mm_struct *mm = get_task_mm(task);
250 if (!mm)
251 goto out;
252 if (!mm->arg_end)
253 goto out_mm; /* Shh! No looking before we're done */
254
255 len = mm->arg_end - mm->arg_start;
256
257 if (len > PAGE_SIZE)
258 len = PAGE_SIZE;
259
260 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
261
262 // If the nul at the end of args has been overwritten, then
263 // assume application is using setproctitle(3).
264 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
265 len = strnlen(buffer, res);
266 if (len < res) {
267 res = len;
268 } else {
269 len = mm->env_end - mm->env_start;
270 if (len > PAGE_SIZE - res)
271 len = PAGE_SIZE - res;
272 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
273 res = strnlen(buffer, res);
274 }
275 }
276out_mm:
277 mmput(mm);
278out:
279 return res;
280}
281
282static int proc_pid_auxv(struct task_struct *task, char *buffer)
283{
284 int res = 0;
285 struct mm_struct *mm = get_task_mm(task);
286 if (mm) {
287 unsigned int nwords = 0;
dfe6b7d9 288 do {
1da177e4 289 nwords += 2;
dfe6b7d9 290 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1da177e4
LT		 291 res = nwords * sizeof(mm->saved_auxv[0]);
292 if (res > PAGE_SIZE)
293 res = PAGE_SIZE;
294 memcpy(buffer, mm->saved_auxv, res);
295 mmput(mm);
296 }
297 return res;
298}
299
300
301#ifdef CONFIG_KALLSYMS
302/*
303 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
304 * Returns the resolved symbol. If that fails, simply return the address.
305 */
306static int proc_pid_wchan(struct task_struct *task, char *buffer)
307{
ffb45122 308 unsigned long wchan;
9281acea 309 char symname[KSYM_NAME_LEN];
1da177e4
LT		 310
311 wchan = get_wchan(task);
312
9d65cb4a 313 if (lookup_symbol_name(wchan, symname) < 0)
f83ce3e6
JE		 314 if (!ptrace_may_access(task, PTRACE_MODE_READ))
315 return 0;
316 else
317 return sprintf(buffer, "%lu", wchan);
9d65cb4a
AD		 318 else
319 return sprintf(buffer, "%s", symname);
1da177e4
LT		 320}
321#endif /* CONFIG_KALLSYMS */
322
2ec220e2
KC		 323#ifdef CONFIG_STACKTRACE
324
325#define MAX_STACK_TRACE_DEPTH 64
326
327static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
328 struct pid *pid, struct task_struct *task)
329{
330 struct stack_trace trace;
331 unsigned long *entries;
332 int i;
333
334 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
335 if (!entries)
336 return -ENOMEM;
337
338 trace.nr_entries = 0;
339 trace.max_entries = MAX_STACK_TRACE_DEPTH;
340 trace.entries = entries;
341 trace.skip = 0;
342 save_stack_trace_tsk(task, &trace);
343
344 for (i = 0; i < trace.nr_entries; i++) {
345 seq_printf(m, "[<%p>] %pS\n",
346 (void *)entries[i], (void *)entries[i]);
347 }
348 kfree(entries);
349
350 return 0;
351}
352#endif
353
1da177e4
LT		 354#ifdef CONFIG_SCHEDSTATS
355/*
356 * Provides /proc/PID/schedstat
357 */
358static int proc_pid_schedstat(struct task_struct *task, char *buffer)
359{
172ba844 360 return sprintf(buffer, "%llu %llu %lu\n",
826e08b0
IM		 361 (unsigned long long)task->se.sum_exec_runtime,
362 (unsigned long long)task->sched_info.run_delay,
2d72376b 363 task->sched_info.pcount);
1da177e4
LT		 364}
365#endif
366
9745512c
AV		 367#ifdef CONFIG_LATENCYTOP
368static int lstats_show_proc(struct seq_file *m, void *v)
369{
370 int i;
13d77c37
HS		 371 struct inode *inode = m->private;
372 struct task_struct *task = get_proc_task(inode);
9745512c 373
13d77c37
HS		 374 if (!task)
375 return -ESRCH;
376 seq_puts(m, "Latency Top version : v0.1\n");
9745512c 377 for (i = 0; i < 32; i++) {
34e49d4f
JP		 378 struct latency_record *lr = &task->latency_record[i];
379 if (lr->backtrace[0]) {
9745512c 380 int q;
34e49d4f
JP		 381 seq_printf(m, "%i %li %li",
382 lr->count, lr->time, lr->max);
9745512c 383 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
34e49d4f
JP		 384 unsigned long bt = lr->backtrace[q];
385 if (!bt)
9745512c 386 break;
34e49d4f 387 if (bt == ULONG_MAX)
9745512c 388 break;
34e49d4f 389 seq_printf(m, " %ps", (void *)bt);
9745512c 390 }
9d6de12f 391 seq_putc(m, '\n');
9745512c
AV		 392 }
393
394 }
13d77c37 395 put_task_struct(task);
9745512c
AV		 396 return 0;
397}
398
399static int lstats_open(struct inode *inode, struct file *file)
400{
13d77c37 401 return single_open(file, lstats_show_proc, inode);
d6643d12
HS		 402}
403
9745512c
AV		 404static ssize_t lstats_write(struct file *file, const char __user *buf,
405 size_t count, loff_t *offs)
406{
13d77c37 407 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
9745512c 408
13d77c37
HS		 409 if (!task)
410 return -ESRCH;
9745512c 411 clear_all_latency_tracing(task);
13d77c37 412 put_task_struct(task);
9745512c
AV		 413
414 return count;
415}
416
417static const struct file_operations proc_lstats_operations = {
418 .open = lstats_open,
419 .read = seq_read,
420 .write = lstats_write,
421 .llseek = seq_lseek,
13d77c37 422 .release = single_release,
9745512c
AV		 423};
424
425#endif
426
1da177e4
LT		 427static int proc_oom_score(struct task_struct *task, char *buffer)
428{
b95c35e7 429 unsigned long points = 0;
1da177e4 430
19c5d45a 431 read_lock(&tasklist_lock);
b95c35e7 432 if (pid_alive(task))
a63d83f4
DR		 433 points = oom_badness(task, NULL, NULL,
434 totalram_pages + total_swap_pages);
19c5d45a 435 read_unlock(&tasklist_lock);
1da177e4
LT		 436 return sprintf(buffer, "%lu\n", points);
437}
438
d85f50d5
NH		 439struct limit_names {
440 char *name;
441 char *unit;
442};
443
444static const struct limit_names lnames[RLIM_NLIMITS] = {
cff4edb5 445 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
d85f50d5
NH		 446 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
447 [RLIMIT_DATA] = {"Max data size", "bytes"},
448 [RLIMIT_STACK] = {"Max stack size", "bytes"},
449 [RLIMIT_CORE] = {"Max core file size", "bytes"},
450 [RLIMIT_RSS] = {"Max resident set", "bytes"},
451 [RLIMIT_NPROC] = {"Max processes", "processes"},
452 [RLIMIT_NOFILE] = {"Max open files", "files"},
453 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
454 [RLIMIT_AS] = {"Max address space", "bytes"},
455 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
456 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
457 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
458 [RLIMIT_NICE] = {"Max nice priority", NULL},
459 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
8808117c 460 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
d85f50d5
NH		 461};
462
463/* Display limits for a process */
464static int proc_pid_limits(struct task_struct *task, char *buffer)
465{
466 unsigned int i;
467 int count = 0;
468 unsigned long flags;
469 char *bufptr = buffer;
470
471 struct rlimit rlim[RLIM_NLIMITS];
472
a6bebbc8 473 if (!lock_task_sighand(task, &flags))
d85f50d5 474 return 0;
d85f50d5
NH		 475 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
476 unlock_task_sighand(task, &flags);
d85f50d5
NH		 477
478 /*
479 * print the file header
480 */
481 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
482 "Limit", "Soft Limit", "Hard Limit", "Units");
483
484 for (i = 0; i < RLIM_NLIMITS; i++) {
485 if (rlim[i].rlim_cur == RLIM_INFINITY)
486 count += sprintf(&bufptr[count], "%-25s %-20s ",
487 lnames[i].name, "unlimited");
488 else
489 count += sprintf(&bufptr[count], "%-25s %-20lu ",
490 lnames[i].name, rlim[i].rlim_cur);
491
492 if (rlim[i].rlim_max == RLIM_INFINITY)
493 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
494 else
495 count += sprintf(&bufptr[count], "%-20lu ",
496 rlim[i].rlim_max);
497
498 if (lnames[i].unit)
499 count += sprintf(&bufptr[count], "%-10s\n",
500 lnames[i].unit);
501 else
502 count += sprintf(&bufptr[count], "\n");
503 }
504
505 return count;
506}
507
ebcb6734
RM		 508#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
509static int proc_pid_syscall(struct task_struct *task, char *buffer)
510{
511 long nr;
512 unsigned long args[6], sp, pc;
513
514 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
515 return sprintf(buffer, "running\n");
516
517 if (nr < 0)
518 return sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
519
520 return sprintf(buffer,
521 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
522 nr,
523 args[0], args[1], args[2], args[3], args[4], args[5],
524 sp, pc);
525}
526#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
527
1da177e4
LT		 528/************************************************************************/
529/* Here the fs part begins */
530/************************************************************************/
531
532/* permission checks */
778c1144 533static int proc_fd_access_allowed(struct inode *inode)
1da177e4 534{
778c1144
EB		 535 struct task_struct *task;
536 int allowed = 0;
df26c40e
EB		 537 /* Allow access to a task's file descriptors if it is us or we
538 * may use ptrace attach to the process and find out that
539 * information.
778c1144
EB		 540 */
541 task = get_proc_task(inode);
df26c40e 542 if (task) {
006ebb40 543 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
778c1144 544 put_task_struct(task);
df26c40e 545 }
778c1144 546 return allowed;
1da177e4
LT		 547}
548
6d76fa58
LT		 549static int proc_setattr(struct dentry *dentry, struct iattr *attr)
550{
551 int error;
552 struct inode *inode = dentry->d_inode;
553
554 if (attr->ia_valid & ATTR_MODE)
555 return -EPERM;
556
557 error = inode_change_ok(inode, attr);
1025774c
CH		 558 if (error)
559 return error;
560
561 if ((attr->ia_valid & ATTR_SIZE) &&
562 attr->ia_size != i_size_read(inode)) {
563 error = vmtruncate(inode, attr->ia_size);
564 if (error)
565 return error;
566 }
567
568 setattr_copy(inode, attr);
569 mark_inode_dirty(inode);
570 return 0;
6d76fa58
LT		 571}
572
c5ef1c42 573static const struct inode_operations proc_def_inode_operations = {
6d76fa58
LT		 574 .setattr = proc_setattr,
575};
576
a1a2c409
MS		 577static int mounts_open_common(struct inode *inode, struct file *file,
578 const struct seq_operations *op)
1da177e4 579{
99f89551 580 struct task_struct *task = get_proc_task(inode);
cf7b708c 581 struct nsproxy *nsp;
6b3286ed 582 struct mnt_namespace *ns = NULL;
a1a2c409 583 struct path root;
5addc5dd
AV		 584 struct proc_mounts *p;
585 int ret = -EINVAL;
1da177e4 586
99f89551 587 if (task) {
cf7b708c
PE		 588 rcu_read_lock();
589 nsp = task_nsproxy(task);
590 if (nsp) {
591 ns = nsp->mnt_ns;
863c4702
AD		 592 if (ns)
593 get_mnt_ns(ns);
594 }
cf7b708c 595 rcu_read_unlock();
f7ad3c6b 596 if (ns && get_task_root(task, &root) == 0)
7c2c7d99 597 ret = 0;
99f89551
EB		 598 put_task_struct(task);
599 }
5addc5dd 600
a1a2c409
MS		 601 if (!ns)
602 goto err;
7c2c7d99 603 if (ret)
a1a2c409
MS		 604 goto err_put_ns;
605
a1a2c409
MS		 606 ret = -ENOMEM;
607 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
608 if (!p)
609 goto err_put_path;
610
611 file->private_data = &p->m;
612 ret = seq_open(file, op);
613 if (ret)
614 goto err_free;
615
616 p->m.private = p;
617 p->ns = ns;
618 p->root = root;
619 p->event = ns->event;
620
621 return 0;
622
623 err_free:
624 kfree(p);
625 err_put_path:
626 path_put(&root);
627 err_put_ns:
628 put_mnt_ns(ns);
629 err:
1da177e4
LT		 630 return ret;
631}
632
633static int mounts_release(struct inode *inode, struct file *file)
634{
a1a2c409
MS		 635 struct proc_mounts *p = file->private_data;
636 path_put(&p->root);
637 put_mnt_ns(p->ns);
1da177e4
LT		 638 return seq_release(inode, file);
639}
640
5addc5dd
AV		 641static unsigned mounts_poll(struct file *file, poll_table *wait)
642{
643 struct proc_mounts *p = file->private_data;
31b07093 644 unsigned res = POLLIN | POLLRDNORM;
5addc5dd 645
9f5596af
AV		 646 poll_wait(file, &p->ns->poll, wait);
647 if (mnt_had_events(p))
31b07093 648 res |= POLLERR | POLLPRI;
5addc5dd
AV		 649
650 return res;
651}
652
a1a2c409
MS		 653static int mounts_open(struct inode *inode, struct file *file)
654{
655 return mounts_open_common(inode, file, &mounts_op);
656}
657
00977a59 658static const struct file_operations proc_mounts_operations = {
1da177e4
LT		 659 .open = mounts_open,
660 .read = seq_read,
661 .llseek = seq_lseek,
662 .release = mounts_release,
5addc5dd 663 .poll = mounts_poll,
1da177e4
LT		 664};
665
2d4d4864
RP		 666static int mountinfo_open(struct inode *inode, struct file *file)
667{
668 return mounts_open_common(inode, file, &mountinfo_op);
669}
670
671static const struct file_operations proc_mountinfo_operations = {
672 .open = mountinfo_open,
673 .read = seq_read,
674 .llseek = seq_lseek,
675 .release = mounts_release,
676 .poll = mounts_poll,
677};
678
b4629fe2
CL		 679static int mountstats_open(struct inode *inode, struct file *file)
680{
a1a2c409 681 return mounts_open_common(inode, file, &mountstats_op);
b4629fe2
CL		 682}
683
00977a59 684static const struct file_operations proc_mountstats_operations = {
b4629fe2
CL		 685 .open = mountstats_open,
686 .read = seq_read,
687 .llseek = seq_lseek,
688 .release = mounts_release,
689};
690
1da177e4
LT		 691#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
692
693static ssize_t proc_info_read(struct file * file, char __user * buf,
694 size_t count, loff_t *ppos)
695{
2fddfeef 696 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 697 unsigned long page;
698 ssize_t length;
99f89551
EB		 699 struct task_struct *task = get_proc_task(inode);
700
701 length = -ESRCH;
702 if (!task)
703 goto out_no_task;
1da177e4
LT		 704
705 if (count > PROC_BLOCK_SIZE)
706 count = PROC_BLOCK_SIZE;
99f89551
EB		 707
708 length = -ENOMEM;
e12ba74d 709 if (!(page = __get_free_page(GFP_TEMPORARY)))
99f89551 710 goto out;
1da177e4
LT		 711
712 length = PROC_I(inode)->op.proc_read(task, (char*)page);
713
714 if (length >= 0)
715 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
716 free_page(page);
99f89551
EB		 717out:
718 put_task_struct(task);
719out_no_task:
1da177e4
LT		 720 return length;
721}
722
00977a59 723static const struct file_operations proc_info_file_operations = {
1da177e4 724 .read = proc_info_read,
87df8424 725 .llseek = generic_file_llseek,
1da177e4
LT		 726};
727
be614086
EB		 728static int proc_single_show(struct seq_file *m, void *v)
729{
730 struct inode *inode = m->private;
731 struct pid_namespace *ns;
732 struct pid *pid;
733 struct task_struct *task;
734 int ret;
735
736 ns = inode->i_sb->s_fs_info;
737 pid = proc_pid(inode);
738 task = get_pid_task(pid, PIDTYPE_PID);
739 if (!task)
740 return -ESRCH;
741
742 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
743
744 put_task_struct(task);
745 return ret;
746}
747
748static int proc_single_open(struct inode *inode, struct file *filp)
749{
c6a34058 750 return single_open(filp, proc_single_show, inode);
be614086
EB		 751}
752
753static const struct file_operations proc_single_file_operations = {
754 .open = proc_single_open,
755 .read = seq_read,
756 .llseek = seq_lseek,
757 .release = single_release,
758};
759
1da177e4
LT		 760static int mem_open(struct inode* inode, struct file* file)
761{
762 file->private_data = (void*)((long)current->self_exec_id);
4a3956c7
KH		 763 /* OK to pass negative loff_t, we can catch out-of-range */
764 file->f_mode |= FMODE_UNSIGNED_OFFSET;
1da177e4
LT		 765 return 0;
766}
767
768static ssize_t mem_read(struct file * file, char __user * buf,
769 size_t count, loff_t *ppos)
770{
2fddfeef 771 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1da177e4
LT		 772 char *page;
773 unsigned long src = *ppos;
774 int ret = -ESRCH;
775 struct mm_struct *mm;
776
99f89551
EB		 777 if (!task)
778 goto out_no_task;
779
638fa202 780 if (check_mem_permission(task))
1da177e4
LT		 781 goto out;
782
783 ret = -ENOMEM;
e12ba74d 784 page = (char *)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 785 if (!page)
786 goto out;
787
788 ret = 0;
789
790 mm = get_task_mm(task);
791 if (!mm)
792 goto out_free;
793
794 ret = -EIO;
795
796 if (file->private_data != (void*)((long)current->self_exec_id))
797 goto out_put;
798
799 ret = 0;
800
801 while (count > 0) {
802 int this_len, retval;
803
804 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
805 retval = access_process_vm(task, src, page, this_len, 0);
638fa202 806 if (!retval || check_mem_permission(task)) {
1da177e4
LT		 807 if (!ret)
808 ret = -EIO;
809 break;
810 }
811
812 if (copy_to_user(buf, page, retval)) {
813 ret = -EFAULT;
814 break;
815 }
816
817 ret += retval;
818 src += retval;
819 buf += retval;
820 count -= retval;
821 }
822 *ppos = src;
823
824out_put:
825 mmput(mm);
826out_free:
827 free_page((unsigned long) page);
828out:
99f89551
EB		 829 put_task_struct(task);
830out_no_task:
1da177e4
LT		 831 return ret;
832}
833
834#define mem_write NULL
835
836#ifndef mem_write
837/* This is a security hazard */
63967fa9 838static ssize_t mem_write(struct file * file, const char __user *buf,
1da177e4
LT		 839 size_t count, loff_t *ppos)
840{
f7ca54f4 841 int copied;
1da177e4 842 char *page;
2fddfeef 843 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1da177e4
LT		 844 unsigned long dst = *ppos;
845
99f89551
EB		 846 copied = -ESRCH;
847 if (!task)
848 goto out_no_task;
849
638fa202 850 if (check_mem_permission(task))
99f89551 851 goto out;
1da177e4 852
99f89551 853 copied = -ENOMEM;
e12ba74d 854 page = (char *)__get_free_page(GFP_TEMPORARY);
1da177e4 855 if (!page)
99f89551 856 goto out;
1da177e4 857
f7ca54f4 858 copied = 0;
1da177e4
LT		 859 while (count > 0) {
860 int this_len, retval;
861
862 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
863 if (copy_from_user(page, buf, this_len)) {
864 copied = -EFAULT;
865 break;
866 }
867 retval = access_process_vm(task, dst, page, this_len, 1);
868 if (!retval) {
869 if (!copied)
870 copied = -EIO;
871 break;
872 }
873 copied += retval;
874 buf += retval;
875 dst += retval;
876 count -= retval;
877 }
878 *ppos = dst;
879 free_page((unsigned long) page);
99f89551
EB		 880out:
881 put_task_struct(task);
882out_no_task:
1da177e4
LT		 883 return copied;
884}
885#endif
886
85863e47 887loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 888{
889 switch (orig) {
890 case 0:
891 file->f_pos = offset;
892 break;
893 case 1:
894 file->f_pos += offset;
895 break;
896 default:
897 return -EINVAL;
898 }
899 force_successful_syscall_return();
900 return file->f_pos;
901}
902
00977a59 903static const struct file_operations proc_mem_operations = {
1da177e4
LT		 904 .llseek = mem_lseek,
905 .read = mem_read,
906 .write = mem_write,
907 .open = mem_open,
908};
909
315e28c8
JP		 910static ssize_t environ_read(struct file *file, char __user *buf,
911 size_t count, loff_t *ppos)
912{
913 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
914 char *page;
915 unsigned long src = *ppos;
916 int ret = -ESRCH;
917 struct mm_struct *mm;
918
919 if (!task)
920 goto out_no_task;
921
006ebb40 922 if (!ptrace_may_access(task, PTRACE_MODE_READ))
315e28c8
JP		 923 goto out;
924
925 ret = -ENOMEM;
926 page = (char *)__get_free_page(GFP_TEMPORARY);
927 if (!page)
928 goto out;
929
930 ret = 0;
931
932 mm = get_task_mm(task);
933 if (!mm)
934 goto out_free;
935
936 while (count > 0) {
937 int this_len, retval, max_len;
938
939 this_len = mm->env_end - (mm->env_start + src);
940
941 if (this_len <= 0)
942 break;
943
944 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
945 this_len = (this_len > max_len) ? max_len : this_len;
946
947 retval = access_process_vm(task, (mm->env_start + src),
948 page, this_len, 0);
949
950 if (retval <= 0) {
951 ret = retval;
952 break;
953 }
954
955 if (copy_to_user(buf, page, retval)) {
956 ret = -EFAULT;
957 break;
958 }
959
960 ret += retval;
961 src += retval;
962 buf += retval;
963 count -= retval;
964 }
965 *ppos = src;
966
967 mmput(mm);
968out_free:
969 free_page((unsigned long) page);
970out:
971 put_task_struct(task);
972out_no_task:
973 return ret;
974}
975
976static const struct file_operations proc_environ_operations = {
977 .read = environ_read,
87df8424 978 .llseek = generic_file_llseek,
315e28c8
JP		 979};
980
1da177e4
LT		 981static ssize_t oom_adjust_read(struct file *file, char __user *buf,
982 size_t count, loff_t *ppos)
983{
2fddfeef 984 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
8578cea7 985 char buffer[PROC_NUMBUF];
1da177e4 986 size_t len;
28b83c51
KM		 987 int oom_adjust = OOM_DISABLE;
988 unsigned long flags;
1da177e4 989
99f89551
EB		 990 if (!task)
991 return -ESRCH;
28b83c51
KM		 992
993 if (lock_task_sighand(task, &flags)) {
994 oom_adjust = task->signal->oom_adj;
995 unlock_task_sighand(task, &flags);
996 }
997
99f89551
EB		 998 put_task_struct(task);
999
8578cea7 1000 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
0c28f287
AM		 1001
1002 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1da177e4
LT		 1003}
1004
1005static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
1006 size_t count, loff_t *ppos)
1007{
99f89551 1008 struct task_struct *task;
5d863b89
KM		 1009 char buffer[PROC_NUMBUF];
1010 long oom_adjust;
28b83c51 1011 unsigned long flags;
5d863b89 1012 int err;
1da177e4 1013
8578cea7
EB		 1014 memset(buffer, 0, sizeof(buffer));
1015 if (count > sizeof(buffer) - 1)
1016 count = sizeof(buffer) - 1;
723548bf
DR		 1017 if (copy_from_user(buffer, buf, count)) {
1018 err = -EFAULT;
1019 goto out;
1020 }
5d863b89
KM		 1021
1022 err = strict_strtol(strstrip(buffer), 0, &oom_adjust);
1023 if (err)
723548bf 1024 goto out;
8ac773b4 1025 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
723548bf
DR		 1026 oom_adjust != OOM_DISABLE) {
1027 err = -EINVAL;
1028 goto out;
1029 }
5d863b89 1030
2fddfeef 1031 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 1032 if (!task) {
1033 err = -ESRCH;
1034 goto out;
1035 }
d19d5476
DR		 1036
1037 task_lock(task);
1038 if (!task->mm) {
1039 err = -EINVAL;
1040 goto err_task_lock;
1041 }
1042
28b83c51 1043 if (!lock_task_sighand(task, &flags)) {
723548bf 1044 err = -ESRCH;
d19d5476 1045 goto err_task_lock;
28b83c51
KM		 1046 }
1047
1048 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 1049 err = -EACCES;
1050 goto err_sighand;
8fb4fc68 1051 }
28b83c51 1052
3d5992d2
YH		 1053 if (oom_adjust != task->signal->oom_adj) {
1054 if (oom_adjust == OOM_DISABLE)
1055 atomic_inc(&task->mm->oom_disable_count);
1056 if (task->signal->oom_adj == OOM_DISABLE)
1057 atomic_dec(&task->mm->oom_disable_count);
1058 }
1059
51b1bd2a
DR		 1060 /*
1061 * Warn that /proc/pid/oom_adj is deprecated, see
1062 * Documentation/feature-removal-schedule.txt.
1063 */
1064 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, "
1065 "please use /proc/%d/oom_score_adj instead.\n",
1066 current->comm, task_pid_nr(current),
1067 task_pid_nr(task), task_pid_nr(task));
28b83c51 1068 task->signal->oom_adj = oom_adjust;
a63d83f4
DR		 1069 /*
1070 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1071 * value is always attainable.
1072 */
1073 if (task->signal->oom_adj == OOM_ADJUST_MAX)
1074 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
1075 else
1076 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
1077 -OOM_DISABLE;
723548bf 1078err_sighand:
28b83c51 1079 unlock_task_sighand(task, &flags);
d19d5476
DR		 1080err_task_lock:
1081 task_unlock(task);
99f89551 1082 put_task_struct(task);
723548bf
DR		 1083out:
1084 return err < 0 ? err : count;
1da177e4
LT		 1085}
1086
00977a59 1087static const struct file_operations proc_oom_adjust_operations = {
1da177e4
LT		 1088 .read = oom_adjust_read,
1089 .write = oom_adjust_write,
87df8424 1090 .llseek = generic_file_llseek,
1da177e4
LT		 1091};
1092
a63d83f4
DR		 1093static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1094 size_t count, loff_t *ppos)
1095{
1096 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1097 char buffer[PROC_NUMBUF];
1098 int oom_score_adj = OOM_SCORE_ADJ_MIN;
1099 unsigned long flags;
1100 size_t len;
1101
1102 if (!task)
1103 return -ESRCH;
1104 if (lock_task_sighand(task, &flags)) {
1105 oom_score_adj = task->signal->oom_score_adj;
1106 unlock_task_sighand(task, &flags);
1107 }
1108 put_task_struct(task);
1109 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
1110 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1111}
1112
1113static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1114 size_t count, loff_t *ppos)
1115{
1116 struct task_struct *task;
1117 char buffer[PROC_NUMBUF];
1118 unsigned long flags;
1119 long oom_score_adj;
1120 int err;
1121
1122 memset(buffer, 0, sizeof(buffer));
1123 if (count > sizeof(buffer) - 1)
1124 count = sizeof(buffer) - 1;
723548bf
DR		 1125 if (copy_from_user(buffer, buf, count)) {
1126 err = -EFAULT;
1127 goto out;
1128 }
a63d83f4
DR		 1129
1130 err = strict_strtol(strstrip(buffer), 0, &oom_score_adj);
1131 if (err)
723548bf 1132 goto out;
a63d83f4 1133 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
723548bf
DR		 1134 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1135 err = -EINVAL;
1136 goto out;
1137 }
a63d83f4
DR		 1138
1139 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 1140 if (!task) {
1141 err = -ESRCH;
1142 goto out;
1143 }
d19d5476
DR		 1144
1145 task_lock(task);
1146 if (!task->mm) {
1147 err = -EINVAL;
1148 goto err_task_lock;
1149 }
1150
a63d83f4 1151 if (!lock_task_sighand(task, &flags)) {
723548bf 1152 err = -ESRCH;
d19d5476 1153 goto err_task_lock;
a63d83f4 1154 }
d19d5476 1155
dabb16f6 1156 if (oom_score_adj < task->signal->oom_score_adj_min &&
a63d83f4 1157 !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 1158 err = -EACCES;
1159 goto err_sighand;
a63d83f4
DR		 1160 }
1161
3d5992d2
YH		 1162 if (oom_score_adj != task->signal->oom_score_adj) {
1163 if (oom_score_adj == OOM_SCORE_ADJ_MIN)
1164 atomic_inc(&task->mm->oom_disable_count);
1165 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1166 atomic_dec(&task->mm->oom_disable_count);
1167 }
a63d83f4 1168 task->signal->oom_score_adj = oom_score_adj;
dabb16f6
MSB		 1169 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1170 task->signal->oom_score_adj_min = oom_score_adj;
a63d83f4
DR		 1171 /*
1172 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1173 * always attainable.
1174 */
1175 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1176 task->signal->oom_adj = OOM_DISABLE;
1177 else
1178 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1179 OOM_SCORE_ADJ_MAX;
723548bf 1180err_sighand:
a63d83f4 1181 unlock_task_sighand(task, &flags);
d19d5476
DR		 1182err_task_lock:
1183 task_unlock(task);
a63d83f4 1184 put_task_struct(task);
723548bf
DR		 1185out:
1186 return err < 0 ? err : count;
a63d83f4
DR		 1187}
1188
1189static const struct file_operations proc_oom_score_adj_operations = {
1190 .read = oom_score_adj_read,
1191 .write = oom_score_adj_write,
6038f373 1192 .llseek = default_llseek,
a63d83f4
DR		 1193};
1194
1da177e4
LT		 1195#ifdef CONFIG_AUDITSYSCALL
1196#define TMPBUFLEN 21
1197static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1198 size_t count, loff_t *ppos)
1199{
2fddfeef 1200 struct inode * inode = file->f_path.dentry->d_inode;
99f89551 1201 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1202 ssize_t length;
1203 char tmpbuf[TMPBUFLEN];
1204
99f89551
EB		 1205 if (!task)
1206 return -ESRCH;
1da177e4 1207 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
0c11b942 1208 audit_get_loginuid(task));
99f89551 1209 put_task_struct(task);
1da177e4
LT		 1210 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1211}
1212
1213static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1214 size_t count, loff_t *ppos)
1215{
2fddfeef 1216 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1217 char *page, *tmp;
1218 ssize_t length;
1da177e4
LT		 1219 uid_t loginuid;
1220
1221 if (!capable(CAP_AUDIT_CONTROL))
1222 return -EPERM;
1223
7dc52157
PM		 1224 rcu_read_lock();
1225 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1226 rcu_read_unlock();
1da177e4 1227 return -EPERM;
7dc52157
PM		 1228 }
1229 rcu_read_unlock();
1da177e4 1230
e0182909
AV		 1231 if (count >= PAGE_SIZE)
1232 count = PAGE_SIZE - 1;
1da177e4
LT		 1233
1234 if (*ppos != 0) {
1235 /* No partial writes. */
1236 return -EINVAL;
1237 }
e12ba74d 1238 page = (char*)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 1239 if (!page)
1240 return -ENOMEM;
1241 length = -EFAULT;
1242 if (copy_from_user(page, buf, count))
1243 goto out_free_page;
1244
e0182909 1245 page[count] = '\0';
1da177e4
LT		 1246 loginuid = simple_strtoul(page, &tmp, 10);
1247 if (tmp == page) {
1248 length = -EINVAL;
1249 goto out_free_page;
1250
1251 }
99f89551 1252 length = audit_set_loginuid(current, loginuid);
1da177e4
LT		 1253 if (likely(length == 0))
1254 length = count;
1255
1256out_free_page:
1257 free_page((unsigned long) page);
1258 return length;
1259}
1260
00977a59 1261static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1262 .read = proc_loginuid_read,
1263 .write = proc_loginuid_write,
87df8424 1264 .llseek = generic_file_llseek,
1da177e4 1265};
1e0bd755
EP		 1266
1267static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1268 size_t count, loff_t *ppos)
1269{
1270 struct inode * inode = file->f_path.dentry->d_inode;
1271 struct task_struct *task = get_proc_task(inode);
1272 ssize_t length;
1273 char tmpbuf[TMPBUFLEN];
1274
1275 if (!task)
1276 return -ESRCH;
1277 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1278 audit_get_sessionid(task));
1279 put_task_struct(task);
1280 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1281}
1282
1283static const struct file_operations proc_sessionid_operations = {
1284 .read = proc_sessionid_read,
87df8424 1285 .llseek = generic_file_llseek,
1e0bd755 1286};
1da177e4
LT		 1287#endif
1288
f4f154fd
AM		 1289#ifdef CONFIG_FAULT_INJECTION
1290static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1291 size_t count, loff_t *ppos)
1292{
1293 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1294 char buffer[PROC_NUMBUF];
1295 size_t len;
1296 int make_it_fail;
f4f154fd
AM		 1297
1298 if (!task)
1299 return -ESRCH;
1300 make_it_fail = task->make_it_fail;
1301 put_task_struct(task);
1302
1303 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1304
1305 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1306}
1307
1308static ssize_t proc_fault_inject_write(struct file * file,
1309 const char __user * buf, size_t count, loff_t *ppos)
1310{
1311 struct task_struct *task;
1312 char buffer[PROC_NUMBUF], *end;
1313 int make_it_fail;
1314
1315 if (!capable(CAP_SYS_RESOURCE))
1316 return -EPERM;
1317 memset(buffer, 0, sizeof(buffer));
1318 if (count > sizeof(buffer) - 1)
1319 count = sizeof(buffer) - 1;
1320 if (copy_from_user(buffer, buf, count))
1321 return -EFAULT;
cba8aafe
VL		 1322 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1323 if (*end)
1324 return -EINVAL;
f4f154fd
AM		 1325 task = get_proc_task(file->f_dentry->d_inode);
1326 if (!task)
1327 return -ESRCH;
1328 task->make_it_fail = make_it_fail;
1329 put_task_struct(task);
cba8aafe
VL		 1330
1331 return count;
f4f154fd
AM		 1332}
1333
00977a59 1334static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1335 .read = proc_fault_inject_read,
1336 .write = proc_fault_inject_write,
87df8424 1337 .llseek = generic_file_llseek,
f4f154fd
AM		 1338};
1339#endif
1340
9745512c 1341
43ae34cb
IM		 1342#ifdef CONFIG_SCHED_DEBUG
1343/*
1344 * Print out various scheduling related per-task fields:
1345 */
1346static int sched_show(struct seq_file *m, void *v)
1347{
1348 struct inode *inode = m->private;
1349 struct task_struct *p;
1350
43ae34cb
IM		 1351 p = get_proc_task(inode);
1352 if (!p)
1353 return -ESRCH;
1354 proc_sched_show_task(p, m);
1355
1356 put_task_struct(p);
1357
1358 return 0;
1359}
1360
1361static ssize_t
1362sched_write(struct file *file, const char __user *buf,
1363 size_t count, loff_t *offset)
1364{
1365 struct inode *inode = file->f_path.dentry->d_inode;
1366 struct task_struct *p;
1367
43ae34cb
IM		 1368 p = get_proc_task(inode);
1369 if (!p)
1370 return -ESRCH;
1371 proc_sched_set_task(p);
1372
1373 put_task_struct(p);
1374
1375 return count;
1376}
1377
1378static int sched_open(struct inode *inode, struct file *filp)
1379{
c6a34058 1380 return single_open(filp, sched_show, inode);
43ae34cb
IM		 1381}
1382
1383static const struct file_operations proc_pid_sched_operations = {
1384 .open = sched_open,
1385 .read = seq_read,
1386 .write = sched_write,
1387 .llseek = seq_lseek,
5ea473a1 1388 .release = single_release,
43ae34cb
IM		 1389};
1390
1391#endif
1392
5091faa4
MG		 1393#ifdef CONFIG_SCHED_AUTOGROUP
1394/*
1395 * Print out autogroup related information:
1396 */
1397static int sched_autogroup_show(struct seq_file *m, void *v)
1398{
1399 struct inode *inode = m->private;
1400 struct task_struct *p;
1401
1402 p = get_proc_task(inode);
1403 if (!p)
1404 return -ESRCH;
1405 proc_sched_autogroup_show_task(p, m);
1406
1407 put_task_struct(p);
1408
1409 return 0;
1410}
1411
1412static ssize_t
1413sched_autogroup_write(struct file *file, const char __user *buf,
1414 size_t count, loff_t *offset)
1415{
1416 struct inode *inode = file->f_path.dentry->d_inode;
1417 struct task_struct *p;
1418 char buffer[PROC_NUMBUF];
1419 long nice;
1420 int err;
1421
1422 memset(buffer, 0, sizeof(buffer));
1423 if (count > sizeof(buffer) - 1)
1424 count = sizeof(buffer) - 1;
1425 if (copy_from_user(buffer, buf, count))
1426 return -EFAULT;
1427
1428 err = strict_strtol(strstrip(buffer), 0, &nice);
1429 if (err)
1430 return -EINVAL;
1431
1432 p = get_proc_task(inode);
1433 if (!p)
1434 return -ESRCH;
1435
1436 err = nice;
1437 err = proc_sched_autogroup_set_nice(p, &err);
1438 if (err)
1439 count = err;
1440
1441 put_task_struct(p);
1442
1443 return count;
1444}
1445
1446static int sched_autogroup_open(struct inode *inode, struct file *filp)
1447{
1448 int ret;
1449
1450 ret = single_open(filp, sched_autogroup_show, NULL);
1451 if (!ret) {
1452 struct seq_file *m = filp->private_data;
1453
1454 m->private = inode;
1455 }
1456 return ret;
1457}
1458
1459static const struct file_operations proc_pid_sched_autogroup_operations = {
1460 .open = sched_autogroup_open,
1461 .read = seq_read,
1462 .write = sched_autogroup_write,
1463 .llseek = seq_lseek,
1464 .release = single_release,
1465};
1466
1467#endif /* CONFIG_SCHED_AUTOGROUP */
1468
4614a696
JS		 1469static ssize_t comm_write(struct file *file, const char __user *buf,
1470 size_t count, loff_t *offset)
1471{
1472 struct inode *inode = file->f_path.dentry->d_inode;
1473 struct task_struct *p;
1474 char buffer[TASK_COMM_LEN];
1475
1476 memset(buffer, 0, sizeof(buffer));
1477 if (count > sizeof(buffer) - 1)
1478 count = sizeof(buffer) - 1;
1479 if (copy_from_user(buffer, buf, count))
1480 return -EFAULT;
1481
1482 p = get_proc_task(inode);
1483 if (!p)
1484 return -ESRCH;
1485
1486 if (same_thread_group(current, p))
1487 set_task_comm(p, buffer);
1488 else
1489 count = -EINVAL;
1490
1491 put_task_struct(p);
1492
1493 return count;
1494}
1495
1496static int comm_show(struct seq_file *m, void *v)
1497{
1498 struct inode *inode = m->private;
1499 struct task_struct *p;
1500
1501 p = get_proc_task(inode);
1502 if (!p)
1503 return -ESRCH;
1504
1505 task_lock(p);
1506 seq_printf(m, "%s\n", p->comm);
1507 task_unlock(p);
1508
1509 put_task_struct(p);
1510
1511 return 0;
1512}
1513
1514static int comm_open(struct inode *inode, struct file *filp)
1515{
c6a34058 1516 return single_open(filp, comm_show, inode);
4614a696
JS		 1517}
1518
1519static const struct file_operations proc_pid_set_comm_operations = {
1520 .open = comm_open,
1521 .read = seq_read,
1522 .write = comm_write,
1523 .llseek = seq_lseek,
1524 .release = single_release,
1525};
1526
925d1c40
MH		 1527/*
1528 * We added or removed a vma mapping the executable. The vmas are only mapped
1529 * during exec and are not mapped with the mmap system call.
1530 * Callers must hold down_write() on the mm's mmap_sem for these
1531 */
1532void added_exe_file_vma(struct mm_struct *mm)
1533{
1534 mm->num_exe_file_vmas++;
1535}
1536
1537void removed_exe_file_vma(struct mm_struct *mm)
1538{
1539 mm->num_exe_file_vmas--;
1540 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){
1541 fput(mm->exe_file);
1542 mm->exe_file = NULL;
1543 }
1544
1545}
1546
1547void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file)
1548{
1549 if (new_exe_file)
1550 get_file(new_exe_file);
1551 if (mm->exe_file)
1552 fput(mm->exe_file);
1553 mm->exe_file = new_exe_file;
1554 mm->num_exe_file_vmas = 0;
1555}
1556
1557struct file *get_mm_exe_file(struct mm_struct *mm)
1558{
1559 struct file *exe_file;
1560
1561 /* We need mmap_sem to protect against races with removal of
1562 * VM_EXECUTABLE vmas */
1563 down_read(&mm->mmap_sem);
1564 exe_file = mm->exe_file;
1565 if (exe_file)
1566 get_file(exe_file);
1567 up_read(&mm->mmap_sem);
1568 return exe_file;
1569}
1570
1571void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm)
1572{
1573 /* It's safe to write the exe_file pointer without exe_file_lock because
1574 * this is called during fork when the task is not yet in /proc */
1575 newmm->exe_file = get_mm_exe_file(oldmm);
1576}
1577
1578static int proc_exe_link(struct inode *inode, struct path *exe_path)
1579{
1580 struct task_struct *task;
1581 struct mm_struct *mm;
1582 struct file *exe_file;
1583
1584 task = get_proc_task(inode);
1585 if (!task)
1586 return -ENOENT;
1587 mm = get_task_mm(task);
1588 put_task_struct(task);
1589 if (!mm)
1590 return -ENOENT;
1591 exe_file = get_mm_exe_file(mm);
1592 mmput(mm);
1593 if (exe_file) {
1594 *exe_path = exe_file->f_path;
1595 path_get(&exe_file->f_path);
1596 fput(exe_file);
1597 return 0;
1598 } else
1599 return -ENOENT;
1600}
1601
008b150a 1602static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1603{
1604 struct inode *inode = dentry->d_inode;
1605 int error = -EACCES;
1606
1607 /* We don't need a base pointer in the /proc filesystem */
1d957f9b 1608 path_put(&nd->path);
1da177e4 1609
778c1144
EB		 1610 /* Are we allowed to snoop on the tasks file descriptors? */
1611 if (!proc_fd_access_allowed(inode))
1da177e4 1612 goto out;
1da177e4 1613
3dcd25f3 1614 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
1da177e4 1615out:
008b150a 1616 return ERR_PTR(error);
1da177e4
LT		 1617}
1618
3dcd25f3 1619static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1620{
e12ba74d 1621 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1622 char *pathname;
1da177e4
LT		 1623 int len;
1624
1625 if (!tmp)
1626 return -ENOMEM;
0c28f287 1627
7b2a69ba 1628 pathname = d_path(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1629 len = PTR_ERR(pathname);
1630 if (IS_ERR(pathname))
1da177e4 1631 goto out;
3dcd25f3 1632 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1633
1634 if (len > buflen)
1635 len = buflen;
3dcd25f3 1636 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1637 len = -EFAULT;
1638 out:
1639 free_page((unsigned long)tmp);
1640 return len;
1641}
1642
1643static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1644{
1645 int error = -EACCES;
1646 struct inode *inode = dentry->d_inode;
3dcd25f3 1647 struct path path;
1da177e4 1648
778c1144
EB		 1649 /* Are we allowed to snoop on the tasks file descriptors? */
1650 if (!proc_fd_access_allowed(inode))
1da177e4 1651 goto out;
1da177e4 1652
3dcd25f3 1653 error = PROC_I(inode)->op.proc_get_link(inode, &path);
1da177e4
LT		 1654 if (error)
1655 goto out;
1656
3dcd25f3
JB		 1657 error = do_proc_readlink(&path, buffer, buflen);
1658 path_put(&path);
1da177e4 1659out:
1da177e4
LT		 1660 return error;
1661}
1662
c5ef1c42 1663static const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1664 .readlink = proc_pid_readlink,
6d76fa58
LT		 1665 .follow_link = proc_pid_follow_link,
1666 .setattr = proc_setattr,
1da177e4
LT		 1667};
1668
28a6d671
EB		 1669
1670/* building an inode */
1671
1672static int task_dumpable(struct task_struct *task)
1da177e4 1673{
28a6d671
EB		 1674 int dumpable = 0;
1675 struct mm_struct *mm;
1da177e4 1676
28a6d671
EB		 1677 task_lock(task);
1678 mm = task->mm;
1679 if (mm)
6c5d5238 1680 dumpable = get_dumpable(mm);
28a6d671
EB		 1681 task_unlock(task);
1682 if(dumpable == 1)
1683 return 1;
1684 return 0;
1685}
1da177e4 1686
1da177e4 1687
61a28784 1688static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1689{
1690 struct inode * inode;
1691 struct proc_inode *ei;
c69e8d9c 1692 const struct cred *cred;
1da177e4 1693
28a6d671 1694 /* We need a new inode */
1da177e4 1695
28a6d671
EB		 1696 inode = new_inode(sb);
1697 if (!inode)
1698 goto out;
1699
1700 /* Common stuff */
1701 ei = PROC_I(inode);
85fe4025 1702 inode->i_ino = get_next_ino();
28a6d671 1703 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
28a6d671
EB		 1704 inode->i_op = &proc_def_inode_operations;
1705
1706 /*
1707 * grab the reference to task.
1708 */
1a657f78 1709 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1710 if (!ei->pid)
1711 goto out_unlock;
1712
28a6d671 1713 if (task_dumpable(task)) {
c69e8d9c
DH		 1714 rcu_read_lock();
1715 cred = __task_cred(task);
1716 inode->i_uid = cred->euid;
1717 inode->i_gid = cred->egid;
1718 rcu_read_unlock();
1da177e4 1719 }
28a6d671
EB		 1720 security_task_to_inode(task, inode);
1721
1da177e4 1722out:
28a6d671
EB		 1723 return inode;
1724
1725out_unlock:
1726 iput(inode);
1727 return NULL;
1da177e4
LT		 1728}
1729
28a6d671 1730static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1731{
1da177e4 1732 struct inode *inode = dentry->d_inode;
28a6d671 1733 struct task_struct *task;
c69e8d9c
DH		 1734 const struct cred *cred;
1735
28a6d671 1736 generic_fillattr(inode, stat);
1da177e4 1737
28a6d671
EB		 1738 rcu_read_lock();
1739 stat->uid = 0;
1740 stat->gid = 0;
1741 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1742 if (task) {
1743 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1744 task_dumpable(task)) {
c69e8d9c
DH		 1745 cred = __task_cred(task);
1746 stat->uid = cred->euid;
1747 stat->gid = cred->egid;
1da177e4
LT		 1748 }
1749 }
28a6d671 1750 rcu_read_unlock();
d6e71144 1751 return 0;
1da177e4
LT		 1752}
1753
1da177e4
LT		 1754/* dentry stuff */
1755
1756/*
1757 * Exceptional case: normally we are not allowed to unhash a busy
1758 * directory. In this case, however, we can do it - no aliasing problems
1759 * due to the way we treat inodes.
1760 *
1761 * Rewrite the inode's ownerships here because the owning task may have
1762 * performed a setuid(), etc.
99f89551
EB		 1763 *
1764 * Before the /proc/pid/status file was created the only way to read
1765 * the effective uid of a /process was to stat /proc/pid. Reading
1766 * /proc/pid/status is slow enough that procps and other packages
1767 * kept stating /proc/pid. To keep the rules in /proc simple I have
1768 * made this apply to all per process world readable and executable
1769 * directories.
1da177e4
LT		 1770 */
1771static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1772{
34286d66
NP		 1773 struct inode *inode;
1774 struct task_struct *task;
c69e8d9c
DH		 1775 const struct cred *cred;
1776
34286d66
NP		 1777 if (nd && nd->flags & LOOKUP_RCU)
1778 return -ECHILD;
1779
1780 inode = dentry->d_inode;
1781 task = get_proc_task(inode);
1782
99f89551
EB		 1783 if (task) {
1784 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1785 task_dumpable(task)) {
c69e8d9c
DH		 1786 rcu_read_lock();
1787 cred = __task_cred(task);
1788 inode->i_uid = cred->euid;
1789 inode->i_gid = cred->egid;
1790 rcu_read_unlock();
1da177e4
LT		 1791 } else {
1792 inode->i_uid = 0;
1793 inode->i_gid = 0;
1794 }
9ee8ab9f 1795 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1796 security_task_to_inode(task, inode);
99f89551 1797 put_task_struct(task);
1da177e4
LT		 1798 return 1;
1799 }
1800 d_drop(dentry);
1801 return 0;
1802}
1803
fe15ce44 1804static int pid_delete_dentry(const struct dentry * dentry)
99f89551 1805{
28a6d671
EB		 1806 /* Is the task we represent dead?
1807 * If so, then don't put the dentry on the lru list,
1808 * kill it immediately.
1809 */
1810 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1811}
1812
d72f71eb 1813static const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1814{
1815 .d_revalidate = pid_revalidate,
1816 .d_delete = pid_delete_dentry,
1817};
1818
1819/* Lookups */
1820
c5141e6d
ED		 1821typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
1822 struct task_struct *, const void *);
61a28784 1823
1c0d04c9
EB		 1824/*
1825 * Fill a directory entry.
1826 *
1827 * If possible create the dcache entry and derive our inode number and
1828 * file type from dcache entry.
1829 *
1830 * Since all of the proc inode numbers are dynamically generated, the inode
1831 * numbers do not exist until the inode is cache. This means creating the
1832 * the dcache entry in readdir is necessary to keep the inode numbers
1833 * reported by readdir in sync with the inode numbers reported
1834 * by stat.
1835 */
61a28784
EB		 1836static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1837 char *name, int len,
c5141e6d 1838 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1839{
2fddfeef 1840 struct dentry *child, *dir = filp->f_path.dentry;
61a28784
EB		 1841 struct inode *inode;
1842 struct qstr qname;
1843 ino_t ino = 0;
1844 unsigned type = DT_UNKNOWN;
1845
1846 qname.name = name;
1847 qname.len = len;
1848 qname.hash = full_name_hash(name, len);
1849
1850 child = d_lookup(dir, &qname);
1851 if (!child) {
1852 struct dentry *new;
1853 new = d_alloc(dir, &qname);
1854 if (new) {
1855 child = instantiate(dir->d_inode, new, task, ptr);
1856 if (child)
1857 dput(new);
1858 else
1859 child = new;
1860 }
1861 }
1862 if (!child || IS_ERR(child) || !child->d_inode)
1863 goto end_instantiate;
1864 inode = child->d_inode;
1865 if (inode) {
1866 ino = inode->i_ino;
1867 type = inode->i_mode >> 12;
1868 }
1869 dput(child);
1870end_instantiate:
1871 if (!ino)
1872 ino = find_inode_number(dir, &qname);
1873 if (!ino)
1874 ino = 1;
1875 return filldir(dirent, name, len, filp->f_pos, ino, type);
1876}
1877
28a6d671
EB		 1878static unsigned name_to_int(struct dentry *dentry)
1879{
1880 const char *name = dentry->d_name.name;
1881 int len = dentry->d_name.len;
1882 unsigned n = 0;
1883
1884 if (len > 1 && *name == '0')
1885 goto out;
1886 while (len-- > 0) {
1887 unsigned c = *name++ - '0';
1888 if (c > 9)
1889 goto out;
1890 if (n >= (~0U-9)/10)
1891 goto out;
1892 n *= 10;
1893 n += c;
1894 }
1895 return n;
1896out:
1897 return ~0U;
1898}
1899
27932742
MS		 1900#define PROC_FDINFO_MAX 64
1901
3dcd25f3 1902static int proc_fd_info(struct inode *inode, struct path *path, char *info)
28a6d671
EB		 1903{
1904 struct task_struct *task = get_proc_task(inode);
1905 struct files_struct *files = NULL;
1906 struct file *file;
1907 int fd = proc_fd(inode);
99f89551 1908
99f89551 1909 if (task) {
28a6d671
EB		 1910 files = get_files_struct(task);
1911 put_task_struct(task);
1912 }
1913 if (files) {
1914 /*
1915 * We are not taking a ref to the file structure, so we must
1916 * hold ->file_lock.
1917 */
1918 spin_lock(&files->file_lock);
1919 file = fcheck_files(files, fd);
1920 if (file) {
3dcd25f3
JB		 1921 if (path) {
1922 *path = file->f_path;
1923 path_get(&file->f_path);
1924 }
27932742
MS		 1925 if (info)
1926 snprintf(info, PROC_FDINFO_MAX,
1927 "pos:\t%lli\n"
1928 "flags:\t0%o\n",
1929 (long long) file->f_pos,
1930 file->f_flags);
28a6d671
EB		 1931 spin_unlock(&files->file_lock);
1932 put_files_struct(files);
1933 return 0;
99f89551 1934 }
28a6d671
EB		 1935 spin_unlock(&files->file_lock);
1936 put_files_struct(files);
99f89551 1937 }
28a6d671 1938 return -ENOENT;
99f89551
EB		 1939}
1940
3dcd25f3 1941static int proc_fd_link(struct inode *inode, struct path *path)
27932742 1942{
3dcd25f3 1943 return proc_fd_info(inode, path, NULL);
27932742
MS		 1944}
1945
1da177e4
LT		 1946static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1947{
34286d66
NP		 1948 struct inode *inode;
1949 struct task_struct *task;
1950 int fd;
1da177e4 1951 struct files_struct *files;
c69e8d9c 1952 const struct cred *cred;
1da177e4 1953
34286d66
NP		 1954 if (nd && nd->flags & LOOKUP_RCU)
1955 return -ECHILD;
1956
1957 inode = dentry->d_inode;
1958 task = get_proc_task(inode);
1959 fd = proc_fd(inode);
1960
99f89551
EB		 1961 if (task) {
1962 files = get_files_struct(task);
1963 if (files) {
1964 rcu_read_lock();
1965 if (fcheck_files(files, fd)) {
1966 rcu_read_unlock();
1967 put_files_struct(files);
1968 if (task_dumpable(task)) {
c69e8d9c
DH		 1969 rcu_read_lock();
1970 cred = __task_cred(task);
1971 inode->i_uid = cred->euid;
1972 inode->i_gid = cred->egid;
1973 rcu_read_unlock();
99f89551
EB		 1974 } else {
1975 inode->i_uid = 0;
1976 inode->i_gid = 0;
1977 }
9ee8ab9f 1978 inode->i_mode &= ~(S_ISUID | S_ISGID);
99f89551
EB		 1979 security_task_to_inode(task, inode);
1980 put_task_struct(task);
1981 return 1;
1982 }
b835996f 1983 rcu_read_unlock();
1da177e4 1984 put_files_struct(files);
1da177e4 1985 }
99f89551 1986 put_task_struct(task);
1da177e4
LT		 1987 }
1988 d_drop(dentry);
1989 return 0;
1990}
1991
d72f71eb 1992static const struct dentry_operations tid_fd_dentry_operations =
1da177e4
LT		 1993{
1994 .d_revalidate = tid_fd_revalidate,
1995 .d_delete = pid_delete_dentry,
1996};
1997
444ceed8 1998static struct dentry *proc_fd_instantiate(struct inode *dir,
c5141e6d 1999 struct dentry *dentry, struct task_struct *task, const void *ptr)
1da177e4 2000{
c5141e6d 2001 unsigned fd = *(const unsigned *)ptr;
444ceed8
EB		 2002 struct file *file;
2003 struct files_struct *files;
2004 struct inode *inode;
2005 struct proc_inode *ei;
2006 struct dentry *error = ERR_PTR(-ENOENT);
1da177e4 2007
61a28784 2008 inode = proc_pid_make_inode(dir->i_sb, task);
1da177e4
LT		 2009 if (!inode)
2010 goto out;
2011 ei = PROC_I(inode);
aed7a6c4 2012 ei->fd = fd;
1da177e4
LT		 2013 files = get_files_struct(task);
2014 if (!files)
444ceed8 2015 goto out_iput;
1da177e4 2016 inode->i_mode = S_IFLNK;
ca99c1da
DS		 2017
2018 /*
2019 * We are not taking a ref to the file structure, so we must
2020 * hold ->file_lock.
2021 */
2022 spin_lock(&files->file_lock);
1da177e4
LT		 2023 file = fcheck_files(files, fd);
2024 if (!file)
444ceed8 2025 goto out_unlock;
aeb5d727 2026 if (file->f_mode & FMODE_READ)
1da177e4 2027 inode->i_mode |= S_IRUSR | S_IXUSR;
aeb5d727 2028 if (file->f_mode & FMODE_WRITE)
1da177e4 2029 inode->i_mode |= S_IWUSR | S_IXUSR;
ca99c1da 2030 spin_unlock(&files->file_lock);
1da177e4 2031 put_files_struct(files);
444ceed8 2032
1da177e4
LT		 2033 inode->i_op = &proc_pid_link_inode_operations;
2034 inode->i_size = 64;
2035 ei->op.proc_get_link = proc_fd_link;
fb045adb 2036 d_set_d_op(dentry, &tid_fd_dentry_operations);
1da177e4 2037 d_add(dentry, inode);
cd6a3ce9
EB		 2038 /* Close the race of the process dying before we return the dentry */
2039 if (tid_fd_revalidate(dentry, NULL))
444ceed8 2040 error = NULL;
1da177e4 2041
444ceed8
EB		 2042 out:
2043 return error;
2044out_unlock:
ca99c1da 2045 spin_unlock(&files->file_lock);
1da177e4 2046 put_files_struct(files);
444ceed8 2047out_iput:
1da177e4 2048 iput(inode);
cd6a3ce9 2049 goto out;
1da177e4
LT		 2050}
2051
27932742
MS		 2052static struct dentry *proc_lookupfd_common(struct inode *dir,
2053 struct dentry *dentry,
2054 instantiate_t instantiate)
444ceed8
EB		 2055{
2056 struct task_struct *task = get_proc_task(dir);
2057 unsigned fd = name_to_int(dentry);
2058 struct dentry *result = ERR_PTR(-ENOENT);
2059
2060 if (!task)
2061 goto out_no_task;
2062 if (fd == ~0U)
2063 goto out;
2064
27932742 2065 result = instantiate(dir, dentry, task, &fd);
444ceed8
EB		 2066out:
2067 put_task_struct(task);
2068out_no_task:
2069 return result;
2070}
2071
27932742
MS		 2072static int proc_readfd_common(struct file * filp, void * dirent,
2073 filldir_t filldir, instantiate_t instantiate)
28a6d671 2074{
2fddfeef 2075 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2076 struct inode *inode = dentry->d_inode;
2077 struct task_struct *p = get_proc_task(inode);
457c2510 2078 unsigned int fd, ino;
28a6d671 2079 int retval;
28a6d671 2080 struct files_struct * files;
1da177e4 2081
28a6d671
EB		 2082 retval = -ENOENT;
2083 if (!p)
2084 goto out_no_task;
2085 retval = 0;
28a6d671
EB		 2086
2087 fd = filp->f_pos;
2088 switch (fd) {
2089 case 0:
2090 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
2091 goto out;
2092 filp->f_pos++;
2093 case 1:
2094 ino = parent_ino(dentry);
2095 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2096 goto out;
2097 filp->f_pos++;
2098 default:
2099 files = get_files_struct(p);
2100 if (!files)
2101 goto out;
2102 rcu_read_lock();
28a6d671 2103 for (fd = filp->f_pos-2;
9b4f526c 2104 fd < files_fdtable(files)->max_fds;
28a6d671 2105 fd++, filp->f_pos++) {
27932742
MS		 2106 char name[PROC_NUMBUF];
2107 int len;
28a6d671
EB		 2108
2109 if (!fcheck_files(files, fd))
2110 continue;
2111 rcu_read_unlock();
2112
27932742
MS		 2113 len = snprintf(name, sizeof(name), "%d", fd);
2114 if (proc_fill_cache(filp, dirent, filldir,
2115 name, len, instantiate,
2116 p, &fd) < 0) {
28a6d671
EB		 2117 rcu_read_lock();
2118 break;
2119 }
2120 rcu_read_lock();
2121 }
2122 rcu_read_unlock();
2123 put_files_struct(files);
2124 }
2125out:
2126 put_task_struct(p);
2127out_no_task:
2128 return retval;
2129}
2130
27932742
MS		 2131static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
2132 struct nameidata *nd)
2133{
2134 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
2135}
2136
2137static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
2138{
2139 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
2140}
2141
2142static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
2143 size_t len, loff_t *ppos)
2144{
2145 char tmp[PROC_FDINFO_MAX];
3dcd25f3 2146 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
27932742
MS		 2147 if (!err)
2148 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
2149 return err;
2150}
2151
2152static const struct file_operations proc_fdinfo_file_operations = {
87df8424 2153 .open = nonseekable_open,
27932742 2154 .read = proc_fdinfo_read,
6038f373 2155 .llseek = no_llseek,
27932742
MS		 2156};
2157
00977a59 2158static const struct file_operations proc_fd_operations = {
28a6d671
EB		 2159 .read = generic_read_dir,
2160 .readdir = proc_readfd,
6038f373 2161 .llseek = default_llseek,
1da177e4
LT		 2162};
2163
8948e11f
AD		 2164/*
2165 * /proc/pid/fd needs a special permission handler so that a process can still
2166 * access /proc/self/fd after it has executed a setuid().
2167 */
b74c79e9 2168static int proc_fd_permission(struct inode *inode, int mask, unsigned int flags)
8948e11f
AD		 2169{
2170 int rv;
2171
b74c79e9
NP		 2172 if (flags & IPERM_FLAG_RCU)
2173 return -ECHILD;
2174 rv = generic_permission(inode, mask, flags, NULL);
8948e11f
AD		 2175 if (rv == 0)
2176 return 0;
2177 if (task_pid(current) == proc_pid(inode))
2178 rv = 0;
2179 return rv;
2180}
2181
1da177e4
LT		 2182/*
2183 * proc directories can do almost nothing..
2184 */
c5ef1c42 2185static const struct inode_operations proc_fd_inode_operations = {
1da177e4 2186 .lookup = proc_lookupfd,
8948e11f 2187 .permission = proc_fd_permission,
6d76fa58 2188 .setattr = proc_setattr,
1da177e4
LT		 2189};
2190
27932742
MS		 2191static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2192 struct dentry *dentry, struct task_struct *task, const void *ptr)
2193{
2194 unsigned fd = *(unsigned *)ptr;
2195 struct inode *inode;
2196 struct proc_inode *ei;
2197 struct dentry *error = ERR_PTR(-ENOENT);
2198
2199 inode = proc_pid_make_inode(dir->i_sb, task);
2200 if (!inode)
2201 goto out;
2202 ei = PROC_I(inode);
2203 ei->fd = fd;
2204 inode->i_mode = S_IFREG | S_IRUSR;
2205 inode->i_fop = &proc_fdinfo_file_operations;
fb045adb 2206 d_set_d_op(dentry, &tid_fd_dentry_operations);
27932742
MS		 2207 d_add(dentry, inode);
2208 /* Close the race of the process dying before we return the dentry */
2209 if (tid_fd_revalidate(dentry, NULL))
2210 error = NULL;
2211
2212 out:
2213 return error;
2214}
2215
2216static struct dentry *proc_lookupfdinfo(struct inode *dir,
2217 struct dentry *dentry,
2218 struct nameidata *nd)
2219{
2220 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2221}
2222
2223static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2224{
2225 return proc_readfd_common(filp, dirent, filldir,
2226 proc_fdinfo_instantiate);
2227}
2228
2229static const struct file_operations proc_fdinfo_operations = {
2230 .read = generic_read_dir,
2231 .readdir = proc_readfdinfo,
6038f373 2232 .llseek = default_llseek,
27932742
MS		 2233};
2234
2235/*
2236 * proc directories can do almost nothing..
2237 */
2238static const struct inode_operations proc_fdinfo_inode_operations = {
2239 .lookup = proc_lookupfdinfo,
2240 .setattr = proc_setattr,
2241};
2242
2243
444ceed8 2244static struct dentry *proc_pident_instantiate(struct inode *dir,
c5141e6d 2245 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2246{
c5141e6d 2247 const struct pid_entry *p = ptr;
444ceed8
EB		 2248 struct inode *inode;
2249 struct proc_inode *ei;
bd6daba9 2250 struct dentry *error = ERR_PTR(-ENOENT);
444ceed8 2251
61a28784 2252 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2253 if (!inode)
2254 goto out;
2255
2256 ei = PROC_I(inode);
2257 inode->i_mode = p->mode;
2258 if (S_ISDIR(inode->i_mode))
2259 inode->i_nlink = 2; /* Use getattr to fix if necessary */
2260 if (p->iop)
2261 inode->i_op = p->iop;
2262 if (p->fop)
2263 inode->i_fop = p->fop;
2264 ei->op = p->op;
fb045adb 2265 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2266 d_add(dentry, inode);
2267 /* Close the race of the process dying before we return the dentry */
2268 if (pid_revalidate(dentry, NULL))
2269 error = NULL;
2270out:
2271 return error;
2272}
2273
1da177e4
LT		 2274static struct dentry *proc_pident_lookup(struct inode *dir,
2275 struct dentry *dentry,
c5141e6d 2276 const struct pid_entry *ents,
7bcd6b0e 2277 unsigned int nents)
1da177e4 2278{
cd6a3ce9 2279 struct dentry *error;
99f89551 2280 struct task_struct *task = get_proc_task(dir);
c5141e6d 2281 const struct pid_entry *p, *last;
1da177e4 2282
cd6a3ce9 2283 error = ERR_PTR(-ENOENT);
1da177e4 2284
99f89551
EB		 2285 if (!task)
2286 goto out_no_task;
1da177e4 2287
20cdc894
EB		 2288 /*
2289 * Yes, it does not scale. And it should not. Don't add
2290 * new entries into /proc/<tgid>/ without very good reasons.
2291 */
7bcd6b0e
EB		 2292 last = &ents[nents - 1];
2293 for (p = ents; p <= last; p++) {
1da177e4
LT		 2294 if (p->len != dentry->d_name.len)
2295 continue;
2296 if (!memcmp(dentry->d_name.name, p->name, p->len))
2297 break;
2298 }
7bcd6b0e 2299 if (p > last)
1da177e4
LT		 2300 goto out;
2301
444ceed8 2302 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2303out:
99f89551
EB		 2304 put_task_struct(task);
2305out_no_task:
cd6a3ce9 2306 return error;
1da177e4
LT		 2307}
2308
c5141e6d
ED		 2309static int proc_pident_fill_cache(struct file *filp, void *dirent,
2310 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2311{
2312 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2313 proc_pident_instantiate, task, p);
2314}
2315
28a6d671
EB		 2316static int proc_pident_readdir(struct file *filp,
2317 void *dirent, filldir_t filldir,
c5141e6d 2318 const struct pid_entry *ents, unsigned int nents)
28a6d671
EB		 2319{
2320 int i;
2fddfeef 2321 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2322 struct inode *inode = dentry->d_inode;
2323 struct task_struct *task = get_proc_task(inode);
c5141e6d 2324 const struct pid_entry *p, *last;
28a6d671
EB		 2325 ino_t ino;
2326 int ret;
2327
2328 ret = -ENOENT;
2329 if (!task)
61a28784 2330 goto out_no_task;
28a6d671
EB		 2331
2332 ret = 0;
28a6d671
EB		 2333 i = filp->f_pos;
2334 switch (i) {
2335 case 0:
2336 ino = inode->i_ino;
2337 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2338 goto out;
2339 i++;
2340 filp->f_pos++;
2341 /* fall through */
2342 case 1:
2343 ino = parent_ino(dentry);
2344 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2345 goto out;
2346 i++;
2347 filp->f_pos++;
2348 /* fall through */
2349 default:
2350 i -= 2;
2351 if (i >= nents) {
2352 ret = 1;
2353 goto out;
2354 }
2355 p = ents + i;
7bcd6b0e
EB		 2356 last = &ents[nents - 1];
2357 while (p <= last) {
61a28784 2358 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
28a6d671
EB		 2359 goto out;
2360 filp->f_pos++;
2361 p++;
2362 }
2363 }
2364
2365 ret = 1;
2366out:
61a28784
EB		 2367 put_task_struct(task);
2368out_no_task:
28a6d671 2369 return ret;
1da177e4
LT		 2370}
2371
28a6d671
EB		 2372#ifdef CONFIG_SECURITY
2373static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2374 size_t count, loff_t *ppos)
2375{
2fddfeef 2376 struct inode * inode = file->f_path.dentry->d_inode;
04ff9708 2377 char *p = NULL;
28a6d671
EB		 2378 ssize_t length;
2379 struct task_struct *task = get_proc_task(inode);
2380
28a6d671 2381 if (!task)
04ff9708 2382 return -ESRCH;
28a6d671
EB		 2383
2384 length = security_getprocattr(task,
2fddfeef 2385 (char*)file->f_path.dentry->d_name.name,
04ff9708 2386 &p);
28a6d671 2387 put_task_struct(task);
04ff9708
AV		 2388 if (length > 0)
2389 length = simple_read_from_buffer(buf, count, ppos, p, length);
2390 kfree(p);
28a6d671 2391 return length;
1da177e4
LT		 2392}
2393
28a6d671
EB		 2394static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2395 size_t count, loff_t *ppos)
2396{
2fddfeef 2397 struct inode * inode = file->f_path.dentry->d_inode;
28a6d671
EB		 2398 char *page;
2399 ssize_t length;
2400 struct task_struct *task = get_proc_task(inode);
2401
2402 length = -ESRCH;
2403 if (!task)
2404 goto out_no_task;
2405 if (count > PAGE_SIZE)
2406 count = PAGE_SIZE;
2407
2408 /* No partial writes. */
2409 length = -EINVAL;
2410 if (*ppos != 0)
2411 goto out;
2412
2413 length = -ENOMEM;
e12ba74d 2414 page = (char*)__get_free_page(GFP_TEMPORARY);
28a6d671
EB		 2415 if (!page)
2416 goto out;
2417
2418 length = -EFAULT;
2419 if (copy_from_user(page, buf, count))
2420 goto out_free;
2421
107db7c7 2422 /* Guard against adverse ptrace interaction */
9b1bf12d 2423 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2424 if (length < 0)
2425 goto out_free;
2426
28a6d671 2427 length = security_setprocattr(task,
2fddfeef 2428 (char*)file->f_path.dentry->d_name.name,
28a6d671 2429 (void*)page, count);
9b1bf12d 2430 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671
EB		 2431out_free:
2432 free_page((unsigned long) page);
2433out:
2434 put_task_struct(task);
2435out_no_task:
2436 return length;
2437}
2438
00977a59 2439static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2440 .read = proc_pid_attr_read,
2441 .write = proc_pid_attr_write,
87df8424 2442 .llseek = generic_file_llseek,
28a6d671
EB		 2443};
2444
c5141e6d 2445static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2446 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2447 REG("prev", S_IRUGO, proc_pid_attr_operations),
2448 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2449 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2450 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2451 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2452};
2453
72d9dcfc 2454static int proc_attr_dir_readdir(struct file * filp,
28a6d671
EB		 2455 void * dirent, filldir_t filldir)
2456{
2457 return proc_pident_readdir(filp,dirent,filldir,
72d9dcfc 2458 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2459}
2460
00977a59 2461static const struct file_operations proc_attr_dir_operations = {
1da177e4 2462 .read = generic_read_dir,
72d9dcfc 2463 .readdir = proc_attr_dir_readdir,
6038f373 2464 .llseek = default_llseek,
1da177e4
LT		 2465};
2466
72d9dcfc 2467static struct dentry *proc_attr_dir_lookup(struct inode *dir,
28a6d671
EB		 2468 struct dentry *dentry, struct nameidata *nd)
2469{
7bcd6b0e
EB		 2470 return proc_pident_lookup(dir, dentry,
2471 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2472}
2473
c5ef1c42 2474static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2475 .lookup = proc_attr_dir_lookup,
99f89551 2476 .getattr = pid_getattr,
6d76fa58 2477 .setattr = proc_setattr,
1da177e4
LT		 2478};
2479
28a6d671
EB		 2480#endif
2481
698ba7b5 2482#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2483static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2484 size_t count, loff_t *ppos)
2485{
2486 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2487 struct mm_struct *mm;
2488 char buffer[PROC_NUMBUF];
2489 size_t len;
2490 int ret;
2491
2492 if (!task)
2493 return -ESRCH;
2494
2495 ret = 0;
2496 mm = get_task_mm(task);
2497 if (mm) {
2498 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2499 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2500 MMF_DUMP_FILTER_SHIFT));
2501 mmput(mm);
2502 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2503 }
2504
2505 put_task_struct(task);
2506
2507 return ret;
2508}
2509
2510static ssize_t proc_coredump_filter_write(struct file *file,
2511 const char __user *buf,
2512 size_t count,
2513 loff_t *ppos)
2514{
2515 struct task_struct *task;
2516 struct mm_struct *mm;
2517 char buffer[PROC_NUMBUF], *end;
2518 unsigned int val;
2519 int ret;
2520 int i;
2521 unsigned long mask;
2522
2523 ret = -EFAULT;
2524 memset(buffer, 0, sizeof(buffer));
2525 if (count > sizeof(buffer) - 1)
2526 count = sizeof(buffer) - 1;
2527 if (copy_from_user(buffer, buf, count))
2528 goto out_no_task;
2529
2530 ret = -EINVAL;
2531 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2532 if (*end == '\n')
2533 end++;
2534 if (end - buffer == 0)
2535 goto out_no_task;
2536
2537 ret = -ESRCH;
2538 task = get_proc_task(file->f_dentry->d_inode);
2539 if (!task)
2540 goto out_no_task;
2541
2542 ret = end - buffer;
2543 mm = get_task_mm(task);
2544 if (!mm)
2545 goto out_no_mm;
2546
2547 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2548 if (val & mask)
2549 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2550 else
2551 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2552 }
2553
2554 mmput(mm);
2555 out_no_mm:
2556 put_task_struct(task);
2557 out_no_task:
2558 return ret;
2559}
2560
2561static const struct file_operations proc_coredump_filter_operations = {
2562 .read = proc_coredump_filter_read,
2563 .write = proc_coredump_filter_write,
87df8424 2564 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2565};
2566#endif
2567
28a6d671
EB		 2568/*
2569 * /proc/self:
2570 */
2571static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2572 int buflen)
2573{
488e5bc4 2574 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2575 pid_t tgid = task_tgid_nr_ns(current, ns);
28a6d671 2576 char tmp[PROC_NUMBUF];
b55fcb22 2577 if (!tgid)
488e5bc4 2578 return -ENOENT;
b55fcb22 2579 sprintf(tmp, "%d", tgid);
28a6d671
EB		 2580 return vfs_readlink(dentry,buffer,buflen,tmp);
2581}
2582
2583static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2584{
488e5bc4 2585 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2586 pid_t tgid = task_tgid_nr_ns(current, ns);
7fee4868
AV		 2587 char *name = ERR_PTR(-ENOENT);
2588 if (tgid) {
2589 name = __getname();
2590 if (!name)
2591 name = ERR_PTR(-ENOMEM);
2592 else
2593 sprintf(name, "%d", tgid);
2594 }
2595 nd_set_link(nd, name);
2596 return NULL;
2597}
2598
2599static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2600 void *cookie)
2601{
2602 char *s = nd_get_link(nd);
2603 if (!IS_ERR(s))
2604 __putname(s);
28a6d671
EB		 2605}
2606
c5ef1c42 2607static const struct inode_operations proc_self_inode_operations = {
28a6d671
EB		 2608 .readlink = proc_self_readlink,
2609 .follow_link = proc_self_follow_link,
7fee4868 2610 .put_link = proc_self_put_link,
28a6d671
EB		 2611};
2612
801199ce
EB		 2613/*
2614 * proc base
2615 *
2616 * These are the directory entries in the root directory of /proc
2617 * that properly belong to the /proc filesystem, as they describe
2618 * describe something that is process related.
2619 */
c5141e6d 2620static const struct pid_entry proc_base_stuff[] = {
61a28784 2621 NOD("self", S_IFLNK|S_IRWXUGO,
801199ce 2622 &proc_self_inode_operations, NULL, {}),
801199ce
EB		 2623};
2624
444ceed8 2625static struct dentry *proc_base_instantiate(struct inode *dir,
c5141e6d 2626 struct dentry *dentry, struct task_struct *task, const void *ptr)
801199ce 2627{
c5141e6d 2628 const struct pid_entry *p = ptr;
801199ce 2629 struct inode *inode;
801199ce 2630 struct proc_inode *ei;
73d36460 2631 struct dentry *error;
801199ce
EB		 2632
2633 /* Allocate the inode */
2634 error = ERR_PTR(-ENOMEM);
2635 inode = new_inode(dir->i_sb);
2636 if (!inode)
2637 goto out;
2638
2639 /* Initialize the inode */
2640 ei = PROC_I(inode);
85fe4025 2641 inode->i_ino = get_next_ino();
801199ce 2642 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
801199ce
EB		 2643
2644 /*
2645 * grab the reference to the task.
2646 */
1a657f78 2647 ei->pid = get_task_pid(task, PIDTYPE_PID);
801199ce
EB		 2648 if (!ei->pid)
2649 goto out_iput;
2650
801199ce
EB		 2651 inode->i_mode = p->mode;
2652 if (S_ISDIR(inode->i_mode))
2653 inode->i_nlink = 2;
2654 if (S_ISLNK(inode->i_mode))
2655 inode->i_size = 64;
2656 if (p->iop)
2657 inode->i_op = p->iop;
2658 if (p->fop)
2659 inode->i_fop = p->fop;
2660 ei->op = p->op;
801199ce
EB		 2661 d_add(dentry, inode);
2662 error = NULL;
2663out:
801199ce
EB		 2664 return error;
2665out_iput:
2666 iput(inode);
2667 goto out;
2668}
2669
444ceed8
EB		 2670static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2671{
2672 struct dentry *error;
2673 struct task_struct *task = get_proc_task(dir);
c5141e6d 2674 const struct pid_entry *p, *last;
444ceed8
EB		 2675
2676 error = ERR_PTR(-ENOENT);
2677
2678 if (!task)
2679 goto out_no_task;
2680
2681 /* Lookup the directory entry */
7bcd6b0e
EB		 2682 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2683 for (p = proc_base_stuff; p <= last; p++) {
444ceed8
EB		 2684 if (p->len != dentry->d_name.len)
2685 continue;
2686 if (!memcmp(dentry->d_name.name, p->name, p->len))
2687 break;
2688 }
7bcd6b0e 2689 if (p > last)
444ceed8
EB		 2690 goto out;
2691
2692 error = proc_base_instantiate(dir, dentry, task, p);
2693
2694out:
2695 put_task_struct(task);
2696out_no_task:
2697 return error;
2698}
2699
c5141e6d
ED		 2700static int proc_base_fill_cache(struct file *filp, void *dirent,
2701 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2702{
2703 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2704 proc_base_instantiate, task, p);
2705}
2706
aba76fdb 2707#ifdef CONFIG_TASK_IO_ACCOUNTING
297c5d92
AR		 2708static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2709{
940389b8 2710 struct task_io_accounting acct = task->ioac;
5995477a
AR		 2711 unsigned long flags;
2712
2713 if (whole && lock_task_sighand(task, &flags)) {
2714 struct task_struct *t = task;
2715
2716 task_io_accounting_add(&acct, &task->signal->ioac);
2717 while_each_thread(task, t)
2718 task_io_accounting_add(&acct, &t->ioac);
2719
2720 unlock_task_sighand(task, &flags);
297c5d92 2721 }
aba76fdb
AM		 2722 return sprintf(buffer,
2723 "rchar: %llu\n"
2724 "wchar: %llu\n"
2725 "syscr: %llu\n"
2726 "syscw: %llu\n"
2727 "read_bytes: %llu\n"
2728 "write_bytes: %llu\n"
2729 "cancelled_write_bytes: %llu\n",
7c44319d
AB		 2730 (unsigned long long)acct.rchar,
2731 (unsigned long long)acct.wchar,
2732 (unsigned long long)acct.syscr,
2733 (unsigned long long)acct.syscw,
2734 (unsigned long long)acct.read_bytes,
2735 (unsigned long long)acct.write_bytes,
2736 (unsigned long long)acct.cancelled_write_bytes);
297c5d92
AR		 2737}
2738
2739static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2740{
2741 return do_io_accounting(task, buffer, 0);
aba76fdb 2742}
297c5d92
AR		 2743
2744static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2745{
2746 return do_io_accounting(task, buffer, 1);
2747}
2748#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2749
47830723
KC		 2750static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2751 struct pid *pid, struct task_struct *task)
2752{
2753 seq_printf(m, "%08x\n", task->personality);
2754 return 0;
2755}
2756
28a6d671
EB		 2757/*
2758 * Thread groups
2759 */
00977a59 2760static const struct file_operations proc_task_operations;
c5ef1c42 2761static const struct inode_operations proc_task_inode_operations;
20cdc894 2762
c5141e6d 2763static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2764 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2765 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2766 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
b2211a36 2767#ifdef CONFIG_NET
631f9c18 2768 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 2769#endif
631f9c18
AD		 2770 REG("environ", S_IRUSR, proc_environ_operations),
2771 INF("auxv", S_IRUSR, proc_pid_auxv),
2772 ONE("status", S_IRUGO, proc_pid_status),
2773 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 2774 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 2775#ifdef CONFIG_SCHED_DEBUG
631f9c18 2776 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
5091faa4
MG		 2777#endif
2778#ifdef CONFIG_SCHED_AUTOGROUP
2779 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
ebcb6734 2780#endif
4614a696 2781 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 2782#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 2783 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 2784#endif
631f9c18
AD		 2785 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2786 ONE("stat", S_IRUGO, proc_tgid_stat),
2787 ONE("statm", S_IRUGO, proc_pid_statm),
2788 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 2789#ifdef CONFIG_NUMA
631f9c18 2790 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 2791#endif
631f9c18
AD		 2792 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2793 LNK("cwd", proc_cwd_link),
2794 LNK("root", proc_root_link),
2795 LNK("exe", proc_exe_link),
2796 REG("mounts", S_IRUGO, proc_mounts_operations),
2797 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2798 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 2799#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 2800 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2801 REG("smaps", S_IRUGO, proc_smaps_operations),
ca6b0bf0 2802 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 2803#endif
2804#ifdef CONFIG_SECURITY
631f9c18 2805 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 2806#endif
2807#ifdef CONFIG_KALLSYMS
631f9c18 2808 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 2809#endif
2ec220e2
KC		 2810#ifdef CONFIG_STACKTRACE
2811 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 2812#endif
2813#ifdef CONFIG_SCHEDSTATS
631f9c18 2814 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 2815#endif
9745512c 2816#ifdef CONFIG_LATENCYTOP
631f9c18 2817 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 2818#endif
8793d854 2819#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 2820 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 2821#endif
2822#ifdef CONFIG_CGROUPS
631f9c18 2823 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 2824#endif
631f9c18
AD		 2825 INF("oom_score", S_IRUGO, proc_oom_score),
2826 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 2827 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 2828#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 2829 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2830 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 2831#endif
f4f154fd 2832#ifdef CONFIG_FAULT_INJECTION
631f9c18 2833 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 2834#endif
698ba7b5 2835#ifdef CONFIG_ELF_CORE
631f9c18 2836 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 2837#endif
aba76fdb 2838#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 2839 INF("io", S_IRUGO, proc_tgid_io_accounting),
aba76fdb 2840#endif
28a6d671 2841};
1da177e4 2842
28a6d671 2843static int proc_tgid_base_readdir(struct file * filp,
1da177e4
LT		 2844 void * dirent, filldir_t filldir)
2845{
2846 return proc_pident_readdir(filp,dirent,filldir,
28a6d671 2847 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2848}
2849
00977a59 2850static const struct file_operations proc_tgid_base_operations = {
1da177e4 2851 .read = generic_read_dir,
28a6d671 2852 .readdir = proc_tgid_base_readdir,
6038f373 2853 .llseek = default_llseek,
1da177e4
LT		 2854};
2855
28a6d671 2856static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 2857 return proc_pident_lookup(dir, dentry,
2858 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2859}
2860
c5ef1c42 2861static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 2862 .lookup = proc_tgid_base_lookup,
99f89551 2863 .getattr = pid_getattr,
6d76fa58 2864 .setattr = proc_setattr,
1da177e4 2865};
1da177e4 2866
60347f67 2867static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 2868{
48e6484d 2869 struct dentry *dentry, *leader, *dir;
8578cea7 2870 char buf[PROC_NUMBUF];
48e6484d
EB		 2871 struct qstr name;
2872
2873 name.name = buf;
60347f67
PE		 2874 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2875 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 2876 if (dentry) {
29f12ca3 2877 shrink_dcache_parent(dentry);
48e6484d
EB		 2878 d_drop(dentry);
2879 dput(dentry);
2880 }
1da177e4 2881
48e6484d 2882 name.name = buf;
60347f67
PE		 2883 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2884 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 2885 if (!leader)
2886 goto out;
1da177e4 2887
48e6484d
EB		 2888 name.name = "task";
2889 name.len = strlen(name.name);
2890 dir = d_hash_and_lookup(leader, &name);
2891 if (!dir)
2892 goto out_put_leader;
2893
2894 name.name = buf;
60347f67 2895 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 2896 dentry = d_hash_and_lookup(dir, &name);
2897 if (dentry) {
2898 shrink_dcache_parent(dentry);
2899 d_drop(dentry);
2900 dput(dentry);
1da177e4 2901 }
48e6484d
EB		 2902
2903 dput(dir);
2904out_put_leader:
2905 dput(leader);
2906out:
2907 return;
1da177e4
LT		 2908}
2909
0895e91d
RD		 2910/**
2911 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2912 * @task: task that should be flushed.
2913 *
2914 * When flushing dentries from proc, one needs to flush them from global
60347f67 2915 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 2916 * in. This call is supposed to do all of this job.
2917 *
2918 * Looks in the dcache for
2919 * /proc/@pid
2920 * /proc/@tgid/task/@pid
2921 * if either directory is present flushes it and all of it'ts children
2922 * from the dcache.
2923 *
2924 * It is safe and reasonable to cache /proc entries for a task until
2925 * that task exits. After that they just clog up the dcache with
2926 * useless entries, possibly causing useful dcache entries to be
2927 * flushed instead. This routine is proved to flush those useless
2928 * dcache entries at process exit time.
2929 *
2930 * NOTE: This routine is just an optimization so it does not guarantee
2931 * that no dcache entries will exist at process exit time it
2932 * just makes it very unlikely that any will persist.
60347f67
PE		 2933 */
2934
2935void proc_flush_task(struct task_struct *task)
2936{
9fcc2d15 2937 int i;
9b4d1cbe 2938 struct pid *pid, *tgid;
130f77ec
PE		 2939 struct upid *upid;
2940
130f77ec 2941 pid = task_pid(task);
9b4d1cbe 2942 tgid = task_tgid(task);
130f77ec 2943
9fcc2d15 2944 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 2945 upid = &pid->numbers[i];
2946 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 2947 tgid->numbers[i].nr);
130f77ec 2948 }
6f4e6433
PE		 2949
2950 upid = &pid->numbers[pid->level];
2951 if (upid->nr == 1)
2952 pid_ns_release_proc(upid->ns);
60347f67
PE		 2953}
2954
9711ef99
AB		 2955static struct dentry *proc_pid_instantiate(struct inode *dir,
2956 struct dentry * dentry,
c5141e6d 2957 struct task_struct *task, const void *ptr)
444ceed8
EB		 2958{
2959 struct dentry *error = ERR_PTR(-ENOENT);
2960 struct inode *inode;
2961
61a28784 2962 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2963 if (!inode)
2964 goto out;
2965
2966 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2967 inode->i_op = &proc_tgid_base_inode_operations;
2968 inode->i_fop = &proc_tgid_base_operations;
2969 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 2970
2971 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
2972 ARRAY_SIZE(tgid_base_stuff));
444ceed8 2973
fb045adb 2974 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2975
2976 d_add(dentry, inode);
2977 /* Close the race of the process dying before we return the dentry */
2978 if (pid_revalidate(dentry, NULL))
2979 error = NULL;
2980out:
2981 return error;
2982}
2983
1da177e4
LT		 2984struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2985{
73d36460 2986 struct dentry *result;
1da177e4 2987 struct task_struct *task;
1da177e4 2988 unsigned tgid;
b488893a 2989 struct pid_namespace *ns;
1da177e4 2990
801199ce
EB		 2991 result = proc_base_lookup(dir, dentry);
2992 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
2993 goto out;
2994
1da177e4
LT		 2995 tgid = name_to_int(dentry);
2996 if (tgid == ~0U)
2997 goto out;
2998
b488893a 2999 ns = dentry->d_sb->s_fs_info;
de758734 3000 rcu_read_lock();
b488893a 3001 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 3002 if (task)
3003 get_task_struct(task);
de758734 3004 rcu_read_unlock();
1da177e4
LT		 3005 if (!task)
3006 goto out;
3007
444ceed8 3008 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 3009 put_task_struct(task);
1da177e4 3010out:
cd6a3ce9 3011 return result;
1da177e4
LT		 3012}
3013
1da177e4 3014/*
0804ef4b 3015 * Find the first task with tgid >= tgid
0bc58a91 3016 *
1da177e4 3017 */
19fd4bb2
EB		 3018struct tgid_iter {
3019 unsigned int tgid;
0804ef4b 3020 struct task_struct *task;
19fd4bb2
EB		 3021};
3022static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3023{
0804ef4b 3024 struct pid *pid;
1da177e4 3025
19fd4bb2
EB		 3026 if (iter.task)
3027 put_task_struct(iter.task);
454cc105 3028 rcu_read_lock();
0804ef4b 3029retry:
19fd4bb2
EB		 3030 iter.task = NULL;
3031 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 3032 if (pid) {
19fd4bb2
EB		 3033 iter.tgid = pid_nr_ns(pid, ns);
3034 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 3035 /* What we to know is if the pid we have find is the
3036 * pid of a thread_group_leader. Testing for task
3037 * being a thread_group_leader is the obvious thing
3038 * todo but there is a window when it fails, due to
3039 * the pid transfer logic in de_thread.
3040 *
3041 * So we perform the straight forward test of seeing
3042 * if the pid we have found is the pid of a thread
3043 * group leader, and don't worry if the task we have
3044 * found doesn't happen to be a thread group leader.
3045 * As we don't care in the case of readdir.
3046 */
19fd4bb2
EB		 3047 if (!iter.task || !has_group_leader_pid(iter.task)) {
3048 iter.tgid += 1;
0804ef4b 3049 goto retry;
19fd4bb2
EB		 3050 }
3051 get_task_struct(iter.task);
0bc58a91 3052 }
454cc105 3053 rcu_read_unlock();
19fd4bb2 3054 return iter;
1da177e4
LT		 3055}
3056
7bcd6b0e 3057#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
0804ef4b 3058
61a28784 3059static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
19fd4bb2 3060 struct tgid_iter iter)
61a28784
EB		 3061{
3062 char name[PROC_NUMBUF];
19fd4bb2 3063 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
61a28784 3064 return proc_fill_cache(filp, dirent, filldir, name, len,
19fd4bb2 3065 proc_pid_instantiate, iter.task, NULL);
61a28784
EB		 3066}
3067
1da177e4
LT		 3068/* for the /proc/ directory itself, after non-process stuff has been done */
3069int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3070{
1da177e4 3071 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2fddfeef 3072 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
19fd4bb2 3073 struct tgid_iter iter;
b488893a 3074 struct pid_namespace *ns;
1da177e4 3075
61a28784
EB		 3076 if (!reaper)
3077 goto out_no_task;
3078
7bcd6b0e 3079 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
c5141e6d 3080 const struct pid_entry *p = &proc_base_stuff[nr];
61a28784 3081 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
801199ce 3082 goto out;
1da177e4
LT		 3083 }
3084
b488893a 3085 ns = filp->f_dentry->d_sb->s_fs_info;
19fd4bb2
EB		 3086 iter.task = NULL;
3087 iter.tgid = filp->f_pos - TGID_OFFSET;
3088 for (iter = next_tgid(ns, iter);
3089 iter.task;
3090 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3091 filp->f_pos = iter.tgid + TGID_OFFSET;
3092 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
3093 put_task_struct(iter.task);
0804ef4b 3094 goto out;
1da177e4 3095 }
0bc58a91 3096 }
0804ef4b
EB		 3097 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3098out:
61a28784
EB		 3099 put_task_struct(reaper);
3100out_no_task:
0bc58a91
EB		 3101 return 0;
3102}
1da177e4 3103
28a6d671
EB		 3104/*
3105 * Tasks
3106 */
c5141e6d 3107static const struct pid_entry tid_base_stuff[] = {
631f9c18 3108 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3109 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
631f9c18
AD		 3110 REG("environ", S_IRUSR, proc_environ_operations),
3111 INF("auxv", S_IRUSR, proc_pid_auxv),
3112 ONE("status", S_IRUGO, proc_pid_status),
3113 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 3114 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3115#ifdef CONFIG_SCHED_DEBUG
631f9c18 3116 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3117#endif
4614a696 3118 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3119#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 3120 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 3121#endif
631f9c18
AD		 3122 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3123 ONE("stat", S_IRUGO, proc_tid_stat),
3124 ONE("statm", S_IRUGO, proc_pid_statm),
3125 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3126#ifdef CONFIG_NUMA
631f9c18 3127 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3128#endif
631f9c18
AD		 3129 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3130 LNK("cwd", proc_cwd_link),
3131 LNK("root", proc_root_link),
3132 LNK("exe", proc_exe_link),
3133 REG("mounts", S_IRUGO, proc_mounts_operations),
3134 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3135#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3136 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3137 REG("smaps", S_IRUGO, proc_smaps_operations),
ca6b0bf0 3138 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 3139#endif
3140#ifdef CONFIG_SECURITY
631f9c18 3141 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3142#endif
3143#ifdef CONFIG_KALLSYMS
631f9c18 3144 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3145#endif
2ec220e2
KC		 3146#ifdef CONFIG_STACKTRACE
3147 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 3148#endif
3149#ifdef CONFIG_SCHEDSTATS
631f9c18 3150 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3151#endif
9745512c 3152#ifdef CONFIG_LATENCYTOP
631f9c18 3153 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3154#endif
8793d854 3155#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3156 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3157#endif
3158#ifdef CONFIG_CGROUPS
631f9c18 3159 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3160#endif
631f9c18
AD		 3161 INF("oom_score", S_IRUGO, proc_oom_score),
3162 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3163 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3164#ifdef CONFIG_AUDITSYSCALL
631f9c18 3165 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
26ec3c64 3166 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3167#endif
f4f154fd 3168#ifdef CONFIG_FAULT_INJECTION
631f9c18 3169 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3170#endif
297c5d92 3171#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 3172 INF("io", S_IRUGO, proc_tid_io_accounting),
297c5d92 3173#endif
28a6d671
EB		 3174};
3175
3176static int proc_tid_base_readdir(struct file * filp,
3177 void * dirent, filldir_t filldir)
3178{
3179 return proc_pident_readdir(filp,dirent,filldir,
3180 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3181}
3182
3183static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3184 return proc_pident_lookup(dir, dentry,
3185 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3186}
3187
00977a59 3188static const struct file_operations proc_tid_base_operations = {
28a6d671
EB		 3189 .read = generic_read_dir,
3190 .readdir = proc_tid_base_readdir,
6038f373 3191 .llseek = default_llseek,
28a6d671
EB		 3192};
3193
c5ef1c42 3194static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3195 .lookup = proc_tid_base_lookup,
3196 .getattr = pid_getattr,
3197 .setattr = proc_setattr,
3198};
3199
444ceed8 3200static struct dentry *proc_task_instantiate(struct inode *dir,
c5141e6d 3201 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8
EB		 3202{
3203 struct dentry *error = ERR_PTR(-ENOENT);
3204 struct inode *inode;
61a28784 3205 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3206
3207 if (!inode)
3208 goto out;
3209 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3210 inode->i_op = &proc_tid_base_inode_operations;
3211 inode->i_fop = &proc_tid_base_operations;
3212 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 3213
3214 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
3215 ARRAY_SIZE(tid_base_stuff));
444ceed8 3216
fb045adb 3217 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3218
3219 d_add(dentry, inode);
3220 /* Close the race of the process dying before we return the dentry */
3221 if (pid_revalidate(dentry, NULL))
3222 error = NULL;
3223out:
3224 return error;
3225}
3226
28a6d671
EB		 3227static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3228{
3229 struct dentry *result = ERR_PTR(-ENOENT);
3230 struct task_struct *task;
3231 struct task_struct *leader = get_proc_task(dir);
28a6d671 3232 unsigned tid;
b488893a 3233 struct pid_namespace *ns;
28a6d671
EB		 3234
3235 if (!leader)
3236 goto out_no_task;
3237
3238 tid = name_to_int(dentry);
3239 if (tid == ~0U)
3240 goto out;
3241
b488893a 3242 ns = dentry->d_sb->s_fs_info;
28a6d671 3243 rcu_read_lock();
b488893a 3244 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3245 if (task)
3246 get_task_struct(task);
3247 rcu_read_unlock();
3248 if (!task)
3249 goto out;
bac0abd6 3250 if (!same_thread_group(leader, task))
28a6d671
EB		 3251 goto out_drop_task;
3252
444ceed8 3253 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3254out_drop_task:
3255 put_task_struct(task);
3256out:
3257 put_task_struct(leader);
3258out_no_task:
3259 return result;
3260}
3261
0bc58a91
EB		 3262/*
3263 * Find the first tid of a thread group to return to user space.
3264 *
3265 * Usually this is just the thread group leader, but if the users
3266 * buffer was too small or there was a seek into the middle of the
3267 * directory we have more work todo.
3268 *
3269 * In the case of a short read we start with find_task_by_pid.
3270 *
3271 * In the case of a seek we start with the leader and walk nr
3272 * threads past it.
3273 */
cc288738 3274static struct task_struct *first_tid(struct task_struct *leader,
b488893a 3275 int tid, int nr, struct pid_namespace *ns)
0bc58a91 3276{
a872ff0c 3277 struct task_struct *pos;
1da177e4 3278
cc288738 3279 rcu_read_lock();
0bc58a91
EB		 3280 /* Attempt to start with the pid of a thread */
3281 if (tid && (nr > 0)) {
b488893a 3282 pos = find_task_by_pid_ns(tid, ns);
a872ff0c
ON		 3283 if (pos && (pos->group_leader == leader))
3284 goto found;
0bc58a91 3285 }
1da177e4 3286
0bc58a91 3287 /* If nr exceeds the number of threads there is nothing todo */
a872ff0c
ON		 3288 pos = NULL;
3289 if (nr && nr >= get_nr_threads(leader))
3290 goto out;
1da177e4 3291
a872ff0c
ON		 3292 /* If we haven't found our starting place yet start
3293 * with the leader and walk nr threads forward.
0bc58a91 3294 */
a872ff0c
ON		 3295 for (pos = leader; nr > 0; --nr) {
3296 pos = next_thread(pos);
3297 if (pos == leader) {
3298 pos = NULL;
3299 goto out;
3300 }
1da177e4 3301 }
a872ff0c
ON		 3302found:
3303 get_task_struct(pos);
3304out:
cc288738 3305 rcu_read_unlock();
0bc58a91
EB		 3306 return pos;
3307}
3308
3309/*
3310 * Find the next thread in the thread list.
3311 * Return NULL if there is an error or no next thread.
3312 *
3313 * The reference to the input task_struct is released.
3314 */
3315static struct task_struct *next_tid(struct task_struct *start)
3316{
c1df7fb8 3317 struct task_struct *pos = NULL;
cc288738 3318 rcu_read_lock();
c1df7fb8 3319 if (pid_alive(start)) {
0bc58a91 3320 pos = next_thread(start);
c1df7fb8
ON		 3321 if (thread_group_leader(pos))
3322 pos = NULL;
3323 else
3324 get_task_struct(pos);
3325 }
cc288738 3326 rcu_read_unlock();
0bc58a91
EB		 3327 put_task_struct(start);
3328 return pos;
1da177e4
LT		 3329}
3330
61a28784
EB		 3331static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3332 struct task_struct *task, int tid)
3333{
3334 char name[PROC_NUMBUF];
3335 int len = snprintf(name, sizeof(name), "%d", tid);
3336 return proc_fill_cache(filp, dirent, filldir, name, len,
3337 proc_task_instantiate, task, NULL);
3338}
3339
1da177e4
LT		 3340/* for the /proc/TGID/task/ directories */
3341static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3342{
2fddfeef 3343 struct dentry *dentry = filp->f_path.dentry;
1da177e4 3344 struct inode *inode = dentry->d_inode;
7d895244 3345 struct task_struct *leader = NULL;
0bc58a91 3346 struct task_struct *task;
1da177e4
LT		 3347 int retval = -ENOENT;
3348 ino_t ino;
0bc58a91 3349 int tid;
b488893a 3350 struct pid_namespace *ns;
1da177e4 3351
7d895244
GC		 3352 task = get_proc_task(inode);
3353 if (!task)
3354 goto out_no_task;
3355 rcu_read_lock();
3356 if (pid_alive(task)) {
3357 leader = task->group_leader;
3358 get_task_struct(leader);
3359 }
3360 rcu_read_unlock();
3361 put_task_struct(task);
99f89551
EB		 3362 if (!leader)
3363 goto out_no_task;
1da177e4
LT		 3364 retval = 0;
3365
ee568b25 3366 switch ((unsigned long)filp->f_pos) {
1da177e4
LT		 3367 case 0:
3368 ino = inode->i_ino;
ee6f779b 3369 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3370 goto out;
ee6f779b 3371 filp->f_pos++;
1da177e4
LT		 3372 /* fall through */
3373 case 1:
3374 ino = parent_ino(dentry);
ee6f779b 3375 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3376 goto out;
ee6f779b 3377 filp->f_pos++;
1da177e4
LT		 3378 /* fall through */
3379 }
3380
0bc58a91
EB		 3381 /* f_version caches the tgid value that the last readdir call couldn't
3382 * return. lseek aka telldir automagically resets f_version to 0.
3383 */
b488893a 3384 ns = filp->f_dentry->d_sb->s_fs_info;
2b47c361 3385 tid = (int)filp->f_version;
0bc58a91 3386 filp->f_version = 0;
ee6f779b 3387 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
0bc58a91 3388 task;
ee6f779b 3389 task = next_tid(task), filp->f_pos++) {
b488893a 3390 tid = task_pid_nr_ns(task, ns);
61a28784 3391 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
0bc58a91
EB		 3392 /* returning this tgid failed, save it as the first
3393 * pid for the next readir call */
2b47c361 3394 filp->f_version = (u64)tid;
0bc58a91 3395 put_task_struct(task);
1da177e4 3396 break;
0bc58a91 3397 }
1da177e4
LT		 3398 }
3399out:
99f89551
EB		 3400 put_task_struct(leader);
3401out_no_task:
1da177e4
LT		 3402 return retval;
3403}
6e66b52b
EB		 3404
3405static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3406{
3407 struct inode *inode = dentry->d_inode;
99f89551 3408 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3409 generic_fillattr(inode, stat);
3410
99f89551 3411 if (p) {
99f89551 3412 stat->nlink += get_nr_threads(p);
99f89551 3413 put_task_struct(p);
6e66b52b
EB		 3414 }
3415
3416 return 0;
3417}
28a6d671 3418
c5ef1c42 3419static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3420 .lookup = proc_task_lookup,
3421 .getattr = proc_task_getattr,
3422 .setattr = proc_setattr,
3423};
3424
00977a59 3425static const struct file_operations proc_task_operations = {
28a6d671
EB		 3426 .read = generic_read_dir,
3427 .readdir = proc_task_readdir,
6038f373 3428 .llseek = default_llseek,
28a6d671 3429};
Michael's Linux tree.