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proc: mem_release() should check mm != NULL
[linux-2.6-block.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>
640708a2 86#include <linux/flex_array.h>
f133ecca
CM		 87#ifdef CONFIG_HARDWALL
88#include <asm/hardwall.h>
89#endif
43d2b113 90#include <trace/events/oom.h>
1da177e4
LT		 91#include "internal.h"
92
0f2fe20f
EB		 93/* NOTE:
94 * Implementing inode permission operations in /proc is almost
95 * certainly an error. Permission checks need to happen during
96 * each system call not at open time. The reason is that most of
97 * what we wish to check for permissions in /proc varies at runtime.
98 *
99 * The classic example of a problem is opening file descriptors
100 * in /proc for a task before it execs a suid executable.
101 */
102
1da177e4 103struct pid_entry {
1da177e4 104 char *name;
c5141e6d 105 int len;
d161a13f 106 umode_t mode;
c5ef1c42 107 const struct inode_operations *iop;
00977a59 108 const struct file_operations *fop;
20cdc894 109 union proc_op op;
1da177e4
LT		 110};
111
61a28784 112#define NOD(NAME, MODE, IOP, FOP, OP) { \
20cdc894 113 .name = (NAME), \
c5141e6d 114 .len = sizeof(NAME) - 1, \
20cdc894
EB		 115 .mode = MODE, \
116 .iop = IOP, \
117 .fop = FOP, \
118 .op = OP, \
119}
120
631f9c18
AD		 121#define DIR(NAME, MODE, iops, fops) \
122 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
123#define LNK(NAME, get_link) \
61a28784 124 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
20cdc894 125 &proc_pid_link_inode_operations, NULL, \
631f9c18
AD		 126 { .proc_get_link = get_link } )
127#define REG(NAME, MODE, fops) \
128 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
129#define INF(NAME, MODE, read) \
61a28784 130 NOD(NAME, (S_IFREG|(MODE)), \
20cdc894 131 NULL, &proc_info_file_operations, \
631f9c18
AD		 132 { .proc_read = read } )
133#define ONE(NAME, MODE, show) \
be614086
EB		 134 NOD(NAME, (S_IFREG|(MODE)), \
135 NULL, &proc_single_file_operations, \
631f9c18 136 { .proc_show = show } )
1da177e4 137
640708a2
PE		 138static int proc_fd_permission(struct inode *inode, int mask);
139
aed54175
VN		 140/*
141 * Count the number of hardlinks for the pid_entry table, excluding the .
142 * and .. links.
143 */
144static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
145 unsigned int n)
146{
147 unsigned int i;
148 unsigned int count;
149
150 count = 0;
151 for (i = 0; i < n; ++i) {
152 if (S_ISDIR(entries[i].mode))
153 ++count;
154 }
155
156 return count;
157}
158
f7ad3c6b 159static int get_task_root(struct task_struct *task, struct path *root)
1da177e4 160{
7c2c7d99
HD		 161 int result = -ENOENT;
162
0494f6ec 163 task_lock(task);
f7ad3c6b
MS		 164 if (task->fs) {
165 get_fs_root(task->fs, root);
7c2c7d99
HD		 166 result = 0;
167 }
0494f6ec 168 task_unlock(task);
7c2c7d99 169 return result;
0494f6ec
MS		 170}
171
7773fbc5 172static int proc_cwd_link(struct dentry *dentry, struct path *path)
0494f6ec 173{
7773fbc5 174 struct task_struct *task = get_proc_task(dentry->d_inode);
0494f6ec 175 int result = -ENOENT;
99f89551
EB		 176
177 if (task) {
f7ad3c6b
MS		 178 task_lock(task);
179 if (task->fs) {
180 get_fs_pwd(task->fs, path);
181 result = 0;
182 }
183 task_unlock(task);
99f89551
EB		 184 put_task_struct(task);
185 }
1da177e4
LT		 186 return result;
187}
188
7773fbc5 189static int proc_root_link(struct dentry *dentry, struct path *path)
1da177e4 190{
7773fbc5 191 struct task_struct *task = get_proc_task(dentry->d_inode);
1da177e4 192 int result = -ENOENT;
99f89551
EB		 193
194 if (task) {
f7ad3c6b 195 result = get_task_root(task, path);
99f89551
EB		 196 put_task_struct(task);
197 }
1da177e4
LT		 198 return result;
199}
200
e268337d 201static struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
831830b5 202{
704b836c 203 struct mm_struct *mm;
ec6fd8a4 204 int err;
704b836c 205
ec6fd8a4
AV		 206 err = mutex_lock_killable(&task->signal->cred_guard_mutex);
207 if (err)
208 return ERR_PTR(err);
00f89d21 209
704b836c
ON		 210 mm = get_task_mm(task);
211 if (mm && mm != current->mm &&
e268337d 212 !ptrace_may_access(task, mode)) {
704b836c 213 mmput(mm);
ec6fd8a4 214 mm = ERR_PTR(-EACCES);
13f0feaf 215 }
9b1bf12d 216 mutex_unlock(&task->signal->cred_guard_mutex);
704b836c 217
831830b5 218 return mm;
831830b5
AV		 219}
220
e268337d
LT		 221struct mm_struct *mm_for_maps(struct task_struct *task)
222{
223 return mm_access(task, PTRACE_MODE_READ);
224}
225
1da177e4
LT		 226static int proc_pid_cmdline(struct task_struct *task, char * buffer)
227{
228 int res = 0;
229 unsigned int len;
230 struct mm_struct *mm = get_task_mm(task);
231 if (!mm)
232 goto out;
233 if (!mm->arg_end)
234 goto out_mm; /* Shh! No looking before we're done */
235
236 len = mm->arg_end - mm->arg_start;
237
238 if (len > PAGE_SIZE)
239 len = PAGE_SIZE;
240
241 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
242
243 // If the nul at the end of args has been overwritten, then
244 // assume application is using setproctitle(3).
245 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
246 len = strnlen(buffer, res);
247 if (len < res) {
248 res = len;
249 } else {
250 len = mm->env_end - mm->env_start;
251 if (len > PAGE_SIZE - res)
252 len = PAGE_SIZE - res;
253 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
254 res = strnlen(buffer, res);
255 }
256 }
257out_mm:
258 mmput(mm);
259out:
260 return res;
261}
262
263static int proc_pid_auxv(struct task_struct *task, char *buffer)
264{
2fadaef4
AV		 265 struct mm_struct *mm = mm_for_maps(task);
266 int res = PTR_ERR(mm);
267 if (mm && !IS_ERR(mm)) {
1da177e4 268 unsigned int nwords = 0;
dfe6b7d9 269 do {
1da177e4 270 nwords += 2;
dfe6b7d9 271 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1da177e4
LT		 272 res = nwords * sizeof(mm->saved_auxv[0]);
273 if (res > PAGE_SIZE)
274 res = PAGE_SIZE;
275 memcpy(buffer, mm->saved_auxv, res);
276 mmput(mm);
277 }
278 return res;
279}
280
281
282#ifdef CONFIG_KALLSYMS
283/*
284 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
285 * Returns the resolved symbol. If that fails, simply return the address.
286 */
287static int proc_pid_wchan(struct task_struct *task, char *buffer)
288{
ffb45122 289 unsigned long wchan;
9281acea 290 char symname[KSYM_NAME_LEN];
1da177e4
LT		 291
292 wchan = get_wchan(task);
293
9d65cb4a 294 if (lookup_symbol_name(wchan, symname) < 0)
f83ce3e6
JE		 295 if (!ptrace_may_access(task, PTRACE_MODE_READ))
296 return 0;
297 else
298 return sprintf(buffer, "%lu", wchan);
9d65cb4a
AD		 299 else
300 return sprintf(buffer, "%s", symname);
1da177e4
LT		 301}
302#endif /* CONFIG_KALLSYMS */
303
a9712bc1
AV		 304static int lock_trace(struct task_struct *task)
305{
306 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
307 if (err)
308 return err;
309 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
310 mutex_unlock(&task->signal->cred_guard_mutex);
311 return -EPERM;
312 }
313 return 0;
314}
315
316static void unlock_trace(struct task_struct *task)
317{
318 mutex_unlock(&task->signal->cred_guard_mutex);
319}
320
2ec220e2
KC		 321#ifdef CONFIG_STACKTRACE
322
323#define MAX_STACK_TRACE_DEPTH 64
324
325static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
326 struct pid *pid, struct task_struct *task)
327{
328 struct stack_trace trace;
329 unsigned long *entries;
a9712bc1 330 int err;
2ec220e2
KC		 331 int i;
332
333 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
334 if (!entries)
335 return -ENOMEM;
336
337 trace.nr_entries = 0;
338 trace.max_entries = MAX_STACK_TRACE_DEPTH;
339 trace.entries = entries;
340 trace.skip = 0;
2ec220e2 341
a9712bc1
AV		 342 err = lock_trace(task);
343 if (!err) {
344 save_stack_trace_tsk(task, &trace);
345
346 for (i = 0; i < trace.nr_entries; i++) {
b81a618d 347 seq_printf(m, "[<%pK>] %pS\n",
a9712bc1
AV		 348 (void *)entries[i], (void *)entries[i]);
349 }
350 unlock_trace(task);
2ec220e2
KC		 351 }
352 kfree(entries);
353
a9712bc1 354 return err;
2ec220e2
KC		 355}
356#endif
357
1da177e4
LT		 358#ifdef CONFIG_SCHEDSTATS
359/*
360 * Provides /proc/PID/schedstat
361 */
362static int proc_pid_schedstat(struct task_struct *task, char *buffer)
363{
172ba844 364 return sprintf(buffer, "%llu %llu %lu\n",
826e08b0
IM		 365 (unsigned long long)task->se.sum_exec_runtime,
366 (unsigned long long)task->sched_info.run_delay,
2d72376b 367 task->sched_info.pcount);
1da177e4
LT		 368}
369#endif
370
9745512c
AV		 371#ifdef CONFIG_LATENCYTOP
372static int lstats_show_proc(struct seq_file *m, void *v)
373{
374 int i;
13d77c37
HS		 375 struct inode *inode = m->private;
376 struct task_struct *task = get_proc_task(inode);
9745512c 377
13d77c37
HS		 378 if (!task)
379 return -ESRCH;
380 seq_puts(m, "Latency Top version : v0.1\n");
9745512c 381 for (i = 0; i < 32; i++) {
34e49d4f
JP		 382 struct latency_record *lr = &task->latency_record[i];
383 if (lr->backtrace[0]) {
9745512c 384 int q;
34e49d4f
JP		 385 seq_printf(m, "%i %li %li",
386 lr->count, lr->time, lr->max);
9745512c 387 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
34e49d4f
JP		 388 unsigned long bt = lr->backtrace[q];
389 if (!bt)
9745512c 390 break;
34e49d4f 391 if (bt == ULONG_MAX)
9745512c 392 break;
34e49d4f 393 seq_printf(m, " %ps", (void *)bt);
9745512c 394 }
9d6de12f 395 seq_putc(m, '\n');
9745512c
AV		 396 }
397
398 }
13d77c37 399 put_task_struct(task);
9745512c
AV		 400 return 0;
401}
402
403static int lstats_open(struct inode *inode, struct file *file)
404{
13d77c37 405 return single_open(file, lstats_show_proc, inode);
d6643d12
HS		 406}
407
9745512c
AV		 408static ssize_t lstats_write(struct file *file, const char __user *buf,
409 size_t count, loff_t *offs)
410{
13d77c37 411 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
9745512c 412
13d77c37
HS		 413 if (!task)
414 return -ESRCH;
9745512c 415 clear_all_latency_tracing(task);
13d77c37 416 put_task_struct(task);
9745512c
AV		 417
418 return count;
419}
420
421static const struct file_operations proc_lstats_operations = {
422 .open = lstats_open,
423 .read = seq_read,
424 .write = lstats_write,
425 .llseek = seq_lseek,
13d77c37 426 .release = single_release,
9745512c
AV		 427};
428
429#endif
430
1da177e4
LT		 431static int proc_oom_score(struct task_struct *task, char *buffer)
432{
b95c35e7 433 unsigned long points = 0;
1da177e4 434
19c5d45a 435 read_lock(&tasklist_lock);
b95c35e7 436 if (pid_alive(task))
a63d83f4
DR		 437 points = oom_badness(task, NULL, NULL,
438 totalram_pages + total_swap_pages);
19c5d45a 439 read_unlock(&tasklist_lock);
1da177e4
LT		 440 return sprintf(buffer, "%lu\n", points);
441}
442
d85f50d5
NH		 443struct limit_names {
444 char *name;
445 char *unit;
446};
447
448static const struct limit_names lnames[RLIM_NLIMITS] = {
cff4edb5 449 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
d85f50d5
NH		 450 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
451 [RLIMIT_DATA] = {"Max data size", "bytes"},
452 [RLIMIT_STACK] = {"Max stack size", "bytes"},
453 [RLIMIT_CORE] = {"Max core file size", "bytes"},
454 [RLIMIT_RSS] = {"Max resident set", "bytes"},
455 [RLIMIT_NPROC] = {"Max processes", "processes"},
456 [RLIMIT_NOFILE] = {"Max open files", "files"},
457 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
458 [RLIMIT_AS] = {"Max address space", "bytes"},
459 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
460 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
461 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
462 [RLIMIT_NICE] = {"Max nice priority", NULL},
463 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
8808117c 464 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
d85f50d5
NH		 465};
466
467/* Display limits for a process */
468static int proc_pid_limits(struct task_struct *task, char *buffer)
469{
470 unsigned int i;
471 int count = 0;
472 unsigned long flags;
473 char *bufptr = buffer;
474
475 struct rlimit rlim[RLIM_NLIMITS];
476
a6bebbc8 477 if (!lock_task_sighand(task, &flags))
d85f50d5 478 return 0;
d85f50d5
NH		 479 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
480 unlock_task_sighand(task, &flags);
d85f50d5
NH		 481
482 /*
483 * print the file header
484 */
485 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
486 "Limit", "Soft Limit", "Hard Limit", "Units");
487
488 for (i = 0; i < RLIM_NLIMITS; i++) {
489 if (rlim[i].rlim_cur == RLIM_INFINITY)
490 count += sprintf(&bufptr[count], "%-25s %-20s ",
491 lnames[i].name, "unlimited");
492 else
493 count += sprintf(&bufptr[count], "%-25s %-20lu ",
494 lnames[i].name, rlim[i].rlim_cur);
495
496 if (rlim[i].rlim_max == RLIM_INFINITY)
497 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
498 else
499 count += sprintf(&bufptr[count], "%-20lu ",
500 rlim[i].rlim_max);
501
502 if (lnames[i].unit)
503 count += sprintf(&bufptr[count], "%-10s\n",
504 lnames[i].unit);
505 else
506 count += sprintf(&bufptr[count], "\n");
507 }
508
509 return count;
510}
511
ebcb6734
RM		 512#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
513static int proc_pid_syscall(struct task_struct *task, char *buffer)
514{
515 long nr;
516 unsigned long args[6], sp, pc;
a9712bc1
AV		 517 int res = lock_trace(task);
518 if (res)
519 return res;
ebcb6734
RM		 520
521 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
a9712bc1
AV		 522 res = sprintf(buffer, "running\n");
523 else if (nr < 0)
524 res = sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
525 else
526 res = sprintf(buffer,
ebcb6734
RM		 527 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
528 nr,
529 args[0], args[1], args[2], args[3], args[4], args[5],
530 sp, pc);
a9712bc1
AV		 531 unlock_trace(task);
532 return res;
ebcb6734
RM		 533}
534#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
535
1da177e4
LT		 536/************************************************************************/
537/* Here the fs part begins */
538/************************************************************************/
539
540/* permission checks */
778c1144 541static int proc_fd_access_allowed(struct inode *inode)
1da177e4 542{
778c1144
EB		 543 struct task_struct *task;
544 int allowed = 0;
df26c40e
EB		 545 /* Allow access to a task's file descriptors if it is us or we
546 * may use ptrace attach to the process and find out that
547 * information.
778c1144
EB		 548 */
549 task = get_proc_task(inode);
df26c40e 550 if (task) {
006ebb40 551 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
778c1144 552 put_task_struct(task);
df26c40e 553 }
778c1144 554 return allowed;
1da177e4
LT		 555}
556
6b4e306a 557int proc_setattr(struct dentry *dentry, struct iattr *attr)
6d76fa58
LT		 558{
559 int error;
560 struct inode *inode = dentry->d_inode;
561
562 if (attr->ia_valid & ATTR_MODE)
563 return -EPERM;
564
565 error = inode_change_ok(inode, attr);
1025774c
CH		 566 if (error)
567 return error;
568
569 if ((attr->ia_valid & ATTR_SIZE) &&
570 attr->ia_size != i_size_read(inode)) {
571 error = vmtruncate(inode, attr->ia_size);
572 if (error)
573 return error;
574 }
575
576 setattr_copy(inode, attr);
577 mark_inode_dirty(inode);
578 return 0;
6d76fa58
LT		 579}
580
0499680a
VK		 581/*
582 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
583 * or euid/egid (for hide_pid_min=2)?
584 */
585static bool has_pid_permissions(struct pid_namespace *pid,
586 struct task_struct *task,
587 int hide_pid_min)
588{
589 if (pid->hide_pid < hide_pid_min)
590 return true;
591 if (in_group_p(pid->pid_gid))
592 return true;
593 return ptrace_may_access(task, PTRACE_MODE_READ);
594}
595
596
597static int proc_pid_permission(struct inode *inode, int mask)
598{
599 struct pid_namespace *pid = inode->i_sb->s_fs_info;
600 struct task_struct *task;
601 bool has_perms;
602
603 task = get_proc_task(inode);
a2ef990a
XF		 604 if (!task)
605 return -ESRCH;
0499680a
VK		 606 has_perms = has_pid_permissions(pid, task, 1);
607 put_task_struct(task);
608
609 if (!has_perms) {
610 if (pid->hide_pid == 2) {
611 /*
612 * Let's make getdents(), stat(), and open()
613 * consistent with each other. If a process
614 * may not stat() a file, it shouldn't be seen
615 * in procfs at all.
616 */
617 return -ENOENT;
618 }
619
620 return -EPERM;
621 }
622 return generic_permission(inode, mask);
623}
624
625
626
c5ef1c42 627static const struct inode_operations proc_def_inode_operations = {
6d76fa58
LT		 628 .setattr = proc_setattr,
629};
630
1da177e4
LT		 631#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
632
633static ssize_t proc_info_read(struct file * file, char __user * buf,
634 size_t count, loff_t *ppos)
635{
2fddfeef 636 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 637 unsigned long page;
638 ssize_t length;
99f89551
EB		 639 struct task_struct *task = get_proc_task(inode);
640
641 length = -ESRCH;
642 if (!task)
643 goto out_no_task;
1da177e4
LT		 644
645 if (count > PROC_BLOCK_SIZE)
646 count = PROC_BLOCK_SIZE;
99f89551
EB		 647
648 length = -ENOMEM;
e12ba74d 649 if (!(page = __get_free_page(GFP_TEMPORARY)))
99f89551 650 goto out;
1da177e4
LT		 651
652 length = PROC_I(inode)->op.proc_read(task, (char*)page);
653
654 if (length >= 0)
655 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
656 free_page(page);
99f89551
EB		 657out:
658 put_task_struct(task);
659out_no_task:
1da177e4
LT		 660 return length;
661}
662
00977a59 663static const struct file_operations proc_info_file_operations = {
1da177e4 664 .read = proc_info_read,
87df8424 665 .llseek = generic_file_llseek,
1da177e4
LT		 666};
667
be614086
EB		 668static int proc_single_show(struct seq_file *m, void *v)
669{
670 struct inode *inode = m->private;
671 struct pid_namespace *ns;
672 struct pid *pid;
673 struct task_struct *task;
674 int ret;
675
676 ns = inode->i_sb->s_fs_info;
677 pid = proc_pid(inode);
678 task = get_pid_task(pid, PIDTYPE_PID);
679 if (!task)
680 return -ESRCH;
681
682 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
683
684 put_task_struct(task);
685 return ret;
686}
687
688static int proc_single_open(struct inode *inode, struct file *filp)
689{
c6a34058 690 return single_open(filp, proc_single_show, inode);
be614086
EB		 691}
692
693static const struct file_operations proc_single_file_operations = {
694 .open = proc_single_open,
695 .read = seq_read,
696 .llseek = seq_lseek,
697 .release = single_release,
698};
699
1da177e4
LT		 700static int mem_open(struct inode* inode, struct file* file)
701{
e268337d
LT		 702 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
703 struct mm_struct *mm;
704
705 if (!task)
706 return -ESRCH;
707
708 mm = mm_access(task, PTRACE_MODE_ATTACH);
709 put_task_struct(task);
710
711 if (IS_ERR(mm))
712 return PTR_ERR(mm);
713
4a3956c7
KH		 714 /* OK to pass negative loff_t, we can catch out-of-range */
715 file->f_mode |= FMODE_UNSIGNED_OFFSET;
e268337d
LT		 716 file->private_data = mm;
717
1da177e4
LT		 718 return 0;
719}
720
721static ssize_t mem_read(struct file * file, char __user * buf,
722 size_t count, loff_t *ppos)
723{
e268337d 724 int ret;
1da177e4
LT		 725 char *page;
726 unsigned long src = *ppos;
e268337d 727 struct mm_struct *mm = file->private_data;
1da177e4 728
e268337d
LT		 729 if (!mm)
730 return 0;
99f89551 731
e12ba74d 732 page = (char *)__get_free_page(GFP_TEMPORARY);
1da177e4 733 if (!page)
e268337d 734 return -ENOMEM;
1da177e4
LT		 735
736 ret = 0;
737
738 while (count > 0) {
739 int this_len, retval;
740
741 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
8b0db9db
SW		 742 retval = access_remote_vm(mm, src, page, this_len, 0);
743 if (!retval) {
1da177e4
LT		 744 if (!ret)
745 ret = -EIO;
746 break;
747 }
748
749 if (copy_to_user(buf, page, retval)) {
750 ret = -EFAULT;
751 break;
752 }
753
754 ret += retval;
755 src += retval;
756 buf += retval;
757 count -= retval;
758 }
759 *ppos = src;
760
1da177e4 761 free_page((unsigned long) page);
1da177e4
LT		 762 return ret;
763}
764
63967fa9 765static ssize_t mem_write(struct file * file, const char __user *buf,
1da177e4
LT		 766 size_t count, loff_t *ppos)
767{
f7ca54f4 768 int copied;
1da177e4 769 char *page;
1da177e4 770 unsigned long dst = *ppos;
e268337d 771 struct mm_struct *mm = file->private_data;
1da177e4 772
e268337d
LT		 773 if (!mm)
774 return 0;
99f89551 775
30cd8903
KM		 776 page = (char *)__get_free_page(GFP_TEMPORARY);
777 if (!page)
e268337d 778 return -ENOMEM;
1da177e4 779
f7ca54f4 780 copied = 0;
1da177e4
LT		 781 while (count > 0) {
782 int this_len, retval;
783
784 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
785 if (copy_from_user(page, buf, this_len)) {
786 copied = -EFAULT;
787 break;
788 }
8b0db9db 789 retval = access_remote_vm(mm, dst, page, this_len, 1);
1da177e4
LT		 790 if (!retval) {
791 if (!copied)
792 copied = -EIO;
793 break;
794 }
795 copied += retval;
796 buf += retval;
797 dst += retval;
798 count -= retval;
799 }
800 *ppos = dst;
30cd8903 801
30cd8903 802 free_page((unsigned long) page);
1da177e4
LT		 803 return copied;
804}
1da177e4 805
85863e47 806loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 807{
808 switch (orig) {
809 case 0:
810 file->f_pos = offset;
811 break;
812 case 1:
813 file->f_pos += offset;
814 break;
815 default:
816 return -EINVAL;
817 }
818 force_successful_syscall_return();
819 return file->f_pos;
820}
821
e268337d
LT		 822static int mem_release(struct inode *inode, struct file *file)
823{
824 struct mm_struct *mm = file->private_data;
71879d3c
ON		 825 if (mm)
826 mmput(mm);
e268337d
LT		 827 return 0;
828}
829
00977a59 830static const struct file_operations proc_mem_operations = {
1da177e4
LT		 831 .llseek = mem_lseek,
832 .read = mem_read,
833 .write = mem_write,
834 .open = mem_open,
e268337d 835 .release = mem_release,
1da177e4
LT		 836};
837
315e28c8
JP		 838static ssize_t environ_read(struct file *file, char __user *buf,
839 size_t count, loff_t *ppos)
840{
841 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
842 char *page;
843 unsigned long src = *ppos;
844 int ret = -ESRCH;
845 struct mm_struct *mm;
846
847 if (!task)
848 goto out_no_task;
849
315e28c8
JP		 850 ret = -ENOMEM;
851 page = (char *)__get_free_page(GFP_TEMPORARY);
852 if (!page)
853 goto out;
854
315e28c8 855
d6f64b89
AV		 856 mm = mm_for_maps(task);
857 ret = PTR_ERR(mm);
858 if (!mm || IS_ERR(mm))
315e28c8
JP		 859 goto out_free;
860
d6f64b89 861 ret = 0;
315e28c8
JP		 862 while (count > 0) {
863 int this_len, retval, max_len;
864
865 this_len = mm->env_end - (mm->env_start + src);
866
867 if (this_len <= 0)
868 break;
869
870 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
871 this_len = (this_len > max_len) ? max_len : this_len;
872
873 retval = access_process_vm(task, (mm->env_start + src),
874 page, this_len, 0);
875
876 if (retval <= 0) {
877 ret = retval;
878 break;
879 }
880
881 if (copy_to_user(buf, page, retval)) {
882 ret = -EFAULT;
883 break;
884 }
885
886 ret += retval;
887 src += retval;
888 buf += retval;
889 count -= retval;
890 }
891 *ppos = src;
892
893 mmput(mm);
894out_free:
895 free_page((unsigned long) page);
896out:
897 put_task_struct(task);
898out_no_task:
899 return ret;
900}
901
902static const struct file_operations proc_environ_operations = {
903 .read = environ_read,
87df8424 904 .llseek = generic_file_llseek,
315e28c8
JP		 905};
906
1da177e4
LT		 907static ssize_t oom_adjust_read(struct file *file, char __user *buf,
908 size_t count, loff_t *ppos)
909{
2fddfeef 910 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
8578cea7 911 char buffer[PROC_NUMBUF];
1da177e4 912 size_t len;
28b83c51
KM		 913 int oom_adjust = OOM_DISABLE;
914 unsigned long flags;
1da177e4 915
99f89551
EB		 916 if (!task)
917 return -ESRCH;
28b83c51
KM		 918
919 if (lock_task_sighand(task, &flags)) {
920 oom_adjust = task->signal->oom_adj;
921 unlock_task_sighand(task, &flags);
922 }
923
99f89551
EB		 924 put_task_struct(task);
925
8578cea7 926 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
0c28f287
AM		 927
928 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1da177e4
LT		 929}
930
931static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
932 size_t count, loff_t *ppos)
933{
99f89551 934 struct task_struct *task;
5d863b89 935 char buffer[PROC_NUMBUF];
0a8cb8e3 936 int oom_adjust;
28b83c51 937 unsigned long flags;
5d863b89 938 int err;
1da177e4 939
8578cea7
EB		 940 memset(buffer, 0, sizeof(buffer));
941 if (count > sizeof(buffer) - 1)
942 count = sizeof(buffer) - 1;
723548bf
DR		 943 if (copy_from_user(buffer, buf, count)) {
944 err = -EFAULT;
945 goto out;
946 }
5d863b89 947
0a8cb8e3 948 err = kstrtoint(strstrip(buffer), 0, &oom_adjust);
5d863b89 949 if (err)
723548bf 950 goto out;
8ac773b4 951 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
723548bf
DR		 952 oom_adjust != OOM_DISABLE) {
953 err = -EINVAL;
954 goto out;
955 }
5d863b89 956
2fddfeef 957 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 958 if (!task) {
959 err = -ESRCH;
960 goto out;
961 }
d19d5476
DR		 962
963 task_lock(task);
964 if (!task->mm) {
965 err = -EINVAL;
966 goto err_task_lock;
967 }
968
28b83c51 969 if (!lock_task_sighand(task, &flags)) {
723548bf 970 err = -ESRCH;
d19d5476 971 goto err_task_lock;
28b83c51
KM		 972 }
973
974 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 975 err = -EACCES;
976 goto err_sighand;
8fb4fc68 977 }
28b83c51 978
51b1bd2a
DR		 979 /*
980 * Warn that /proc/pid/oom_adj is deprecated, see
981 * Documentation/feature-removal-schedule.txt.
982 */
c2142704 983 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
be8f684d
DR		 984 current->comm, task_pid_nr(current), task_pid_nr(task),
985 task_pid_nr(task));
28b83c51 986 task->signal->oom_adj = oom_adjust;
a63d83f4
DR		 987 /*
988 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
989 * value is always attainable.
990 */
991 if (task->signal->oom_adj == OOM_ADJUST_MAX)
992 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
993 else
994 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
995 -OOM_DISABLE;
43d2b113 996 trace_oom_score_adj_update(task);
723548bf 997err_sighand:
28b83c51 998 unlock_task_sighand(task, &flags);
d19d5476
DR		 999err_task_lock:
1000 task_unlock(task);
99f89551 1001 put_task_struct(task);
723548bf
DR		 1002out:
1003 return err < 0 ? err : count;
1da177e4
LT		 1004}
1005
00977a59 1006static const struct file_operations proc_oom_adjust_operations = {
1da177e4
LT		 1007 .read = oom_adjust_read,
1008 .write = oom_adjust_write,
87df8424 1009 .llseek = generic_file_llseek,
1da177e4
LT		 1010};
1011
a63d83f4
DR		 1012static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1013 size_t count, loff_t *ppos)
1014{
1015 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1016 char buffer[PROC_NUMBUF];
1017 int oom_score_adj = OOM_SCORE_ADJ_MIN;
1018 unsigned long flags;
1019 size_t len;
1020
1021 if (!task)
1022 return -ESRCH;
1023 if (lock_task_sighand(task, &flags)) {
1024 oom_score_adj = task->signal->oom_score_adj;
1025 unlock_task_sighand(task, &flags);
1026 }
1027 put_task_struct(task);
1028 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
1029 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1030}
1031
1032static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1033 size_t count, loff_t *ppos)
1034{
1035 struct task_struct *task;
1036 char buffer[PROC_NUMBUF];
1037 unsigned long flags;
0a8cb8e3 1038 int oom_score_adj;
a63d83f4
DR		 1039 int err;
1040
1041 memset(buffer, 0, sizeof(buffer));
1042 if (count > sizeof(buffer) - 1)
1043 count = sizeof(buffer) - 1;
723548bf
DR		 1044 if (copy_from_user(buffer, buf, count)) {
1045 err = -EFAULT;
1046 goto out;
1047 }
a63d83f4 1048
0a8cb8e3 1049 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
a63d83f4 1050 if (err)
723548bf 1051 goto out;
a63d83f4 1052 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
723548bf
DR		 1053 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1054 err = -EINVAL;
1055 goto out;
1056 }
a63d83f4
DR		 1057
1058 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 1059 if (!task) {
1060 err = -ESRCH;
1061 goto out;
1062 }
d19d5476
DR		 1063
1064 task_lock(task);
1065 if (!task->mm) {
1066 err = -EINVAL;
1067 goto err_task_lock;
1068 }
1069
a63d83f4 1070 if (!lock_task_sighand(task, &flags)) {
723548bf 1071 err = -ESRCH;
d19d5476 1072 goto err_task_lock;
a63d83f4 1073 }
d19d5476 1074
dabb16f6 1075 if (oom_score_adj < task->signal->oom_score_adj_min &&
a63d83f4 1076 !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 1077 err = -EACCES;
1078 goto err_sighand;
a63d83f4
DR		 1079 }
1080
1081 task->signal->oom_score_adj = oom_score_adj;
dabb16f6
MSB		 1082 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1083 task->signal->oom_score_adj_min = oom_score_adj;
43d2b113 1084 trace_oom_score_adj_update(task);
a63d83f4
DR		 1085 /*
1086 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1087 * always attainable.
1088 */
1089 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1090 task->signal->oom_adj = OOM_DISABLE;
1091 else
1092 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1093 OOM_SCORE_ADJ_MAX;
723548bf 1094err_sighand:
a63d83f4 1095 unlock_task_sighand(task, &flags);
d19d5476
DR		 1096err_task_lock:
1097 task_unlock(task);
a63d83f4 1098 put_task_struct(task);
723548bf
DR		 1099out:
1100 return err < 0 ? err : count;
a63d83f4
DR		 1101}
1102
1103static const struct file_operations proc_oom_score_adj_operations = {
1104 .read = oom_score_adj_read,
1105 .write = oom_score_adj_write,
6038f373 1106 .llseek = default_llseek,
a63d83f4
DR		 1107};
1108
1da177e4
LT		 1109#ifdef CONFIG_AUDITSYSCALL
1110#define TMPBUFLEN 21
1111static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1112 size_t count, loff_t *ppos)
1113{
2fddfeef 1114 struct inode * inode = file->f_path.dentry->d_inode;
99f89551 1115 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1116 ssize_t length;
1117 char tmpbuf[TMPBUFLEN];
1118
99f89551
EB		 1119 if (!task)
1120 return -ESRCH;
1da177e4 1121 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
0c11b942 1122 audit_get_loginuid(task));
99f89551 1123 put_task_struct(task);
1da177e4
LT		 1124 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1125}
1126
1127static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1128 size_t count, loff_t *ppos)
1129{
2fddfeef 1130 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1131 char *page, *tmp;
1132 ssize_t length;
1da177e4
LT		 1133 uid_t loginuid;
1134
7dc52157
PM		 1135 rcu_read_lock();
1136 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1137 rcu_read_unlock();
1da177e4 1138 return -EPERM;
7dc52157
PM		 1139 }
1140 rcu_read_unlock();
1da177e4 1141
e0182909
AV		 1142 if (count >= PAGE_SIZE)
1143 count = PAGE_SIZE - 1;
1da177e4
LT		 1144
1145 if (*ppos != 0) {
1146 /* No partial writes. */
1147 return -EINVAL;
1148 }
e12ba74d 1149 page = (char*)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 1150 if (!page)
1151 return -ENOMEM;
1152 length = -EFAULT;
1153 if (copy_from_user(page, buf, count))
1154 goto out_free_page;
1155
e0182909 1156 page[count] = '\0';
1da177e4
LT		 1157 loginuid = simple_strtoul(page, &tmp, 10);
1158 if (tmp == page) {
1159 length = -EINVAL;
1160 goto out_free_page;
1161
1162 }
0a300be6 1163 length = audit_set_loginuid(loginuid);
1da177e4
LT		 1164 if (likely(length == 0))
1165 length = count;
1166
1167out_free_page:
1168 free_page((unsigned long) page);
1169 return length;
1170}
1171
00977a59 1172static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1173 .read = proc_loginuid_read,
1174 .write = proc_loginuid_write,
87df8424 1175 .llseek = generic_file_llseek,
1da177e4 1176};
1e0bd755
EP		 1177
1178static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1179 size_t count, loff_t *ppos)
1180{
1181 struct inode * inode = file->f_path.dentry->d_inode;
1182 struct task_struct *task = get_proc_task(inode);
1183 ssize_t length;
1184 char tmpbuf[TMPBUFLEN];
1185
1186 if (!task)
1187 return -ESRCH;
1188 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1189 audit_get_sessionid(task));
1190 put_task_struct(task);
1191 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1192}
1193
1194static const struct file_operations proc_sessionid_operations = {
1195 .read = proc_sessionid_read,
87df8424 1196 .llseek = generic_file_llseek,
1e0bd755 1197};
1da177e4
LT		 1198#endif
1199
f4f154fd
AM		 1200#ifdef CONFIG_FAULT_INJECTION
1201static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1202 size_t count, loff_t *ppos)
1203{
1204 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1205 char buffer[PROC_NUMBUF];
1206 size_t len;
1207 int make_it_fail;
f4f154fd
AM		 1208
1209 if (!task)
1210 return -ESRCH;
1211 make_it_fail = task->make_it_fail;
1212 put_task_struct(task);
1213
1214 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1215
1216 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1217}
1218
1219static ssize_t proc_fault_inject_write(struct file * file,
1220 const char __user * buf, size_t count, loff_t *ppos)
1221{
1222 struct task_struct *task;
1223 char buffer[PROC_NUMBUF], *end;
1224 int make_it_fail;
1225
1226 if (!capable(CAP_SYS_RESOURCE))
1227 return -EPERM;
1228 memset(buffer, 0, sizeof(buffer));
1229 if (count > sizeof(buffer) - 1)
1230 count = sizeof(buffer) - 1;
1231 if (copy_from_user(buffer, buf, count))
1232 return -EFAULT;
cba8aafe
VL		 1233 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1234 if (*end)
1235 return -EINVAL;
f4f154fd
AM		 1236 task = get_proc_task(file->f_dentry->d_inode);
1237 if (!task)
1238 return -ESRCH;
1239 task->make_it_fail = make_it_fail;
1240 put_task_struct(task);
cba8aafe
VL		 1241
1242 return count;
f4f154fd
AM		 1243}
1244
00977a59 1245static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1246 .read = proc_fault_inject_read,
1247 .write = proc_fault_inject_write,
87df8424 1248 .llseek = generic_file_llseek,
f4f154fd
AM		 1249};
1250#endif
1251
9745512c 1252
43ae34cb
IM		 1253#ifdef CONFIG_SCHED_DEBUG
1254/*
1255 * Print out various scheduling related per-task fields:
1256 */
1257static int sched_show(struct seq_file *m, void *v)
1258{
1259 struct inode *inode = m->private;
1260 struct task_struct *p;
1261
43ae34cb
IM		 1262 p = get_proc_task(inode);
1263 if (!p)
1264 return -ESRCH;
1265 proc_sched_show_task(p, m);
1266
1267 put_task_struct(p);
1268
1269 return 0;
1270}
1271
1272static ssize_t
1273sched_write(struct file *file, const char __user *buf,
1274 size_t count, loff_t *offset)
1275{
1276 struct inode *inode = file->f_path.dentry->d_inode;
1277 struct task_struct *p;
1278
43ae34cb
IM		 1279 p = get_proc_task(inode);
1280 if (!p)
1281 return -ESRCH;
1282 proc_sched_set_task(p);
1283
1284 put_task_struct(p);
1285
1286 return count;
1287}
1288
1289static int sched_open(struct inode *inode, struct file *filp)
1290{
c6a34058 1291 return single_open(filp, sched_show, inode);
43ae34cb
IM		 1292}
1293
1294static const struct file_operations proc_pid_sched_operations = {
1295 .open = sched_open,
1296 .read = seq_read,
1297 .write = sched_write,
1298 .llseek = seq_lseek,
5ea473a1 1299 .release = single_release,
43ae34cb
IM		 1300};
1301
1302#endif
1303
5091faa4
MG		 1304#ifdef CONFIG_SCHED_AUTOGROUP
1305/*
1306 * Print out autogroup related information:
1307 */
1308static int sched_autogroup_show(struct seq_file *m, void *v)
1309{
1310 struct inode *inode = m->private;
1311 struct task_struct *p;
1312
1313 p = get_proc_task(inode);
1314 if (!p)
1315 return -ESRCH;
1316 proc_sched_autogroup_show_task(p, m);
1317
1318 put_task_struct(p);
1319
1320 return 0;
1321}
1322
1323static ssize_t
1324sched_autogroup_write(struct file *file, const char __user *buf,
1325 size_t count, loff_t *offset)
1326{
1327 struct inode *inode = file->f_path.dentry->d_inode;
1328 struct task_struct *p;
1329 char buffer[PROC_NUMBUF];
0a8cb8e3 1330 int nice;
5091faa4
MG		 1331 int err;
1332
1333 memset(buffer, 0, sizeof(buffer));
1334 if (count > sizeof(buffer) - 1)
1335 count = sizeof(buffer) - 1;
1336 if (copy_from_user(buffer, buf, count))
1337 return -EFAULT;
1338
0a8cb8e3
AD		 1339 err = kstrtoint(strstrip(buffer), 0, &nice);
1340 if (err < 0)
1341 return err;
5091faa4
MG		 1342
1343 p = get_proc_task(inode);
1344 if (!p)
1345 return -ESRCH;
1346
1347 err = nice;
1348 err = proc_sched_autogroup_set_nice(p, &err);
1349 if (err)
1350 count = err;
1351
1352 put_task_struct(p);
1353
1354 return count;
1355}
1356
1357static int sched_autogroup_open(struct inode *inode, struct file *filp)
1358{
1359 int ret;
1360
1361 ret = single_open(filp, sched_autogroup_show, NULL);
1362 if (!ret) {
1363 struct seq_file *m = filp->private_data;
1364
1365 m->private = inode;
1366 }
1367 return ret;
1368}
1369
1370static const struct file_operations proc_pid_sched_autogroup_operations = {
1371 .open = sched_autogroup_open,
1372 .read = seq_read,
1373 .write = sched_autogroup_write,
1374 .llseek = seq_lseek,
1375 .release = single_release,
1376};
1377
1378#endif /* CONFIG_SCHED_AUTOGROUP */
1379
4614a696 1380static ssize_t comm_write(struct file *file, const char __user *buf,
1381 size_t count, loff_t *offset)
1382{
1383 struct inode *inode = file->f_path.dentry->d_inode;
1384 struct task_struct *p;
1385 char buffer[TASK_COMM_LEN];
1386
1387 memset(buffer, 0, sizeof(buffer));
1388 if (count > sizeof(buffer) - 1)
1389 count = sizeof(buffer) - 1;
1390 if (copy_from_user(buffer, buf, count))
1391 return -EFAULT;
1392
1393 p = get_proc_task(inode);
1394 if (!p)
1395 return -ESRCH;
1396
1397 if (same_thread_group(current, p))
1398 set_task_comm(p, buffer);
1399 else
1400 count = -EINVAL;
1401
1402 put_task_struct(p);
1403
1404 return count;
1405}
1406
1407static int comm_show(struct seq_file *m, void *v)
1408{
1409 struct inode *inode = m->private;
1410 struct task_struct *p;
1411
1412 p = get_proc_task(inode);
1413 if (!p)
1414 return -ESRCH;
1415
1416 task_lock(p);
1417 seq_printf(m, "%s\n", p->comm);
1418 task_unlock(p);
1419
1420 put_task_struct(p);
1421
1422 return 0;
1423}
1424
1425static int comm_open(struct inode *inode, struct file *filp)
1426{
c6a34058 1427 return single_open(filp, comm_show, inode);
4614a696 1428}
1429
1430static const struct file_operations proc_pid_set_comm_operations = {
1431 .open = comm_open,
1432 .read = seq_read,
1433 .write = comm_write,
1434 .llseek = seq_lseek,
1435 .release = single_release,
1436};
1437
7773fbc5 1438static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
925d1c40
MH		 1439{
1440 struct task_struct *task;
1441 struct mm_struct *mm;
1442 struct file *exe_file;
1443
7773fbc5 1444 task = get_proc_task(dentry->d_inode);
925d1c40
MH		 1445 if (!task)
1446 return -ENOENT;
1447 mm = get_task_mm(task);
1448 put_task_struct(task);
1449 if (!mm)
1450 return -ENOENT;
1451 exe_file = get_mm_exe_file(mm);
1452 mmput(mm);
1453 if (exe_file) {
1454 *exe_path = exe_file->f_path;
1455 path_get(&exe_file->f_path);
1456 fput(exe_file);
1457 return 0;
1458 } else
1459 return -ENOENT;
1460}
1461
008b150a 1462static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1463{
1464 struct inode *inode = dentry->d_inode;
1465 int error = -EACCES;
1466
1467 /* We don't need a base pointer in the /proc filesystem */
1d957f9b 1468 path_put(&nd->path);
1da177e4 1469
778c1144
EB		 1470 /* Are we allowed to snoop on the tasks file descriptors? */
1471 if (!proc_fd_access_allowed(inode))
1da177e4 1472 goto out;
1da177e4 1473
7773fbc5 1474 error = PROC_I(inode)->op.proc_get_link(dentry, &nd->path);
1da177e4 1475out:
008b150a 1476 return ERR_PTR(error);
1da177e4
LT		 1477}
1478
3dcd25f3 1479static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1480{
e12ba74d 1481 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1482 char *pathname;
1da177e4
LT		 1483 int len;
1484
1485 if (!tmp)
1486 return -ENOMEM;
0c28f287 1487
7b2a69ba 1488 pathname = d_path(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1489 len = PTR_ERR(pathname);
1490 if (IS_ERR(pathname))
1da177e4 1491 goto out;
3dcd25f3 1492 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1493
1494 if (len > buflen)
1495 len = buflen;
3dcd25f3 1496 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1497 len = -EFAULT;
1498 out:
1499 free_page((unsigned long)tmp);
1500 return len;
1501}
1502
1503static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1504{
1505 int error = -EACCES;
1506 struct inode *inode = dentry->d_inode;
3dcd25f3 1507 struct path path;
1da177e4 1508
778c1144
EB		 1509 /* Are we allowed to snoop on the tasks file descriptors? */
1510 if (!proc_fd_access_allowed(inode))
1da177e4 1511 goto out;
1da177e4 1512
7773fbc5 1513 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1da177e4
LT		 1514 if (error)
1515 goto out;
1516
3dcd25f3
JB		 1517 error = do_proc_readlink(&path, buffer, buflen);
1518 path_put(&path);
1da177e4 1519out:
1da177e4
LT		 1520 return error;
1521}
1522
c5ef1c42 1523static const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1524 .readlink = proc_pid_readlink,
6d76fa58
LT		 1525 .follow_link = proc_pid_follow_link,
1526 .setattr = proc_setattr,
1da177e4
LT		 1527};
1528
28a6d671
EB		 1529
1530/* building an inode */
1531
1532static int task_dumpable(struct task_struct *task)
1da177e4 1533{
28a6d671
EB		 1534 int dumpable = 0;
1535 struct mm_struct *mm;
1da177e4 1536
28a6d671
EB		 1537 task_lock(task);
1538 mm = task->mm;
1539 if (mm)
6c5d5238 1540 dumpable = get_dumpable(mm);
28a6d671
EB		 1541 task_unlock(task);
1542 if(dumpable == 1)
1543 return 1;
1544 return 0;
1545}
1da177e4 1546
6b4e306a 1547struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1548{
1549 struct inode * inode;
1550 struct proc_inode *ei;
c69e8d9c 1551 const struct cred *cred;
1da177e4 1552
28a6d671 1553 /* We need a new inode */
1da177e4 1554
28a6d671
EB		 1555 inode = new_inode(sb);
1556 if (!inode)
1557 goto out;
1558
1559 /* Common stuff */
1560 ei = PROC_I(inode);
85fe4025 1561 inode->i_ino = get_next_ino();
28a6d671 1562 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
28a6d671
EB		 1563 inode->i_op = &proc_def_inode_operations;
1564
1565 /*
1566 * grab the reference to task.
1567 */
1a657f78 1568 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1569 if (!ei->pid)
1570 goto out_unlock;
1571
28a6d671 1572 if (task_dumpable(task)) {
c69e8d9c
DH		 1573 rcu_read_lock();
1574 cred = __task_cred(task);
1575 inode->i_uid = cred->euid;
1576 inode->i_gid = cred->egid;
1577 rcu_read_unlock();
1da177e4 1578 }
28a6d671
EB		 1579 security_task_to_inode(task, inode);
1580
1da177e4 1581out:
28a6d671
EB		 1582 return inode;
1583
1584out_unlock:
1585 iput(inode);
1586 return NULL;
1da177e4
LT		 1587}
1588
6b4e306a 1589int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1590{
1da177e4 1591 struct inode *inode = dentry->d_inode;
28a6d671 1592 struct task_struct *task;
c69e8d9c 1593 const struct cred *cred;
0499680a 1594 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
c69e8d9c 1595
28a6d671 1596 generic_fillattr(inode, stat);
1da177e4 1597
28a6d671
EB		 1598 rcu_read_lock();
1599 stat->uid = 0;
1600 stat->gid = 0;
1601 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1602 if (task) {
0499680a
VK		 1603 if (!has_pid_permissions(pid, task, 2)) {
1604 rcu_read_unlock();
1605 /*
1606 * This doesn't prevent learning whether PID exists,
1607 * it only makes getattr() consistent with readdir().
1608 */
1609 return -ENOENT;
1610 }
28a6d671
EB		 1611 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1612 task_dumpable(task)) {
c69e8d9c
DH		 1613 cred = __task_cred(task);
1614 stat->uid = cred->euid;
1615 stat->gid = cred->egid;
1da177e4
LT		 1616 }
1617 }
28a6d671 1618 rcu_read_unlock();
d6e71144 1619 return 0;
1da177e4
LT		 1620}
1621
1da177e4
LT		 1622/* dentry stuff */
1623
1624/*
1625 * Exceptional case: normally we are not allowed to unhash a busy
1626 * directory. In this case, however, we can do it - no aliasing problems
1627 * due to the way we treat inodes.
1628 *
1629 * Rewrite the inode's ownerships here because the owning task may have
1630 * performed a setuid(), etc.
99f89551
EB		 1631 *
1632 * Before the /proc/pid/status file was created the only way to read
1633 * the effective uid of a /process was to stat /proc/pid. Reading
1634 * /proc/pid/status is slow enough that procps and other packages
1635 * kept stating /proc/pid. To keep the rules in /proc simple I have
1636 * made this apply to all per process world readable and executable
1637 * directories.
1da177e4 1638 */
6b4e306a 1639int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1da177e4 1640{
34286d66
NP		 1641 struct inode *inode;
1642 struct task_struct *task;
c69e8d9c
DH		 1643 const struct cred *cred;
1644
34286d66
NP		 1645 if (nd && nd->flags & LOOKUP_RCU)
1646 return -ECHILD;
1647
1648 inode = dentry->d_inode;
1649 task = get_proc_task(inode);
1650
99f89551
EB		 1651 if (task) {
1652 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1653 task_dumpable(task)) {
c69e8d9c
DH		 1654 rcu_read_lock();
1655 cred = __task_cred(task);
1656 inode->i_uid = cred->euid;
1657 inode->i_gid = cred->egid;
1658 rcu_read_unlock();
1da177e4
LT		 1659 } else {
1660 inode->i_uid = 0;
1661 inode->i_gid = 0;
1662 }
9ee8ab9f 1663 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1664 security_task_to_inode(task, inode);
99f89551 1665 put_task_struct(task);
1da177e4
LT		 1666 return 1;
1667 }
1668 d_drop(dentry);
1669 return 0;
1670}
1671
fe15ce44 1672static int pid_delete_dentry(const struct dentry * dentry)
99f89551 1673{
28a6d671
EB		 1674 /* Is the task we represent dead?
1675 * If so, then don't put the dentry on the lru list,
1676 * kill it immediately.
1677 */
1678 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1679}
1680
6b4e306a 1681const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1682{
1683 .d_revalidate = pid_revalidate,
1684 .d_delete = pid_delete_dentry,
1685};
1686
1687/* Lookups */
1688
1c0d04c9
EB		 1689/*
1690 * Fill a directory entry.
1691 *
1692 * If possible create the dcache entry and derive our inode number and
1693 * file type from dcache entry.
1694 *
1695 * Since all of the proc inode numbers are dynamically generated, the inode
1696 * numbers do not exist until the inode is cache. This means creating the
1697 * the dcache entry in readdir is necessary to keep the inode numbers
1698 * reported by readdir in sync with the inode numbers reported
1699 * by stat.
1700 */
6b4e306a
EB		 1701int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1702 const char *name, int len,
c5141e6d 1703 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1704{
2fddfeef 1705 struct dentry *child, *dir = filp->f_path.dentry;
61a28784
EB		 1706 struct inode *inode;
1707 struct qstr qname;
1708 ino_t ino = 0;
1709 unsigned type = DT_UNKNOWN;
1710
1711 qname.name = name;
1712 qname.len = len;
1713 qname.hash = full_name_hash(name, len);
1714
1715 child = d_lookup(dir, &qname);
1716 if (!child) {
1717 struct dentry *new;
1718 new = d_alloc(dir, &qname);
1719 if (new) {
1720 child = instantiate(dir->d_inode, new, task, ptr);
1721 if (child)
1722 dput(new);
1723 else
1724 child = new;
1725 }
1726 }
1727 if (!child || IS_ERR(child) || !child->d_inode)
1728 goto end_instantiate;
1729 inode = child->d_inode;
1730 if (inode) {
1731 ino = inode->i_ino;
1732 type = inode->i_mode >> 12;
1733 }
1734 dput(child);
1735end_instantiate:
1736 if (!ino)
1737 ino = find_inode_number(dir, &qname);
1738 if (!ino)
1739 ino = 1;
1740 return filldir(dirent, name, len, filp->f_pos, ino, type);
1741}
1742
28a6d671
EB		 1743static unsigned name_to_int(struct dentry *dentry)
1744{
1745 const char *name = dentry->d_name.name;
1746 int len = dentry->d_name.len;
1747 unsigned n = 0;
1748
1749 if (len > 1 && *name == '0')
1750 goto out;
1751 while (len-- > 0) {
1752 unsigned c = *name++ - '0';
1753 if (c > 9)
1754 goto out;
1755 if (n >= (~0U-9)/10)
1756 goto out;
1757 n *= 10;
1758 n += c;
1759 }
1760 return n;
1761out:
1762 return ~0U;
1763}
1764
27932742
MS		 1765#define PROC_FDINFO_MAX 64
1766
3dcd25f3 1767static int proc_fd_info(struct inode *inode, struct path *path, char *info)
28a6d671 1768{
5e442a49
LT		 1769 struct task_struct *task = get_proc_task(inode);
1770 struct files_struct *files = NULL;
28a6d671
EB		 1771 struct file *file;
1772 int fd = proc_fd(inode);
aa6afca5 1773
5e442a49
LT		 1774 if (task) {
1775 files = get_files_struct(task);
1776 put_task_struct(task);
1777 }
1778 if (files) {
1779 /*
1780 * We are not taking a ref to the file structure, so we must
1781 * hold ->file_lock.
1782 */
1783 spin_lock(&files->file_lock);
1784 file = fcheck_files(files, fd);
1785 if (file) {
1786 unsigned int f_flags;
1787 struct fdtable *fdt;
1788
1789 fdt = files_fdtable(files);
1790 f_flags = file->f_flags & ~O_CLOEXEC;
1791 if (FD_ISSET(fd, fdt->close_on_exec))
1792 f_flags |= O_CLOEXEC;
1793
1794 if (path) {
1795 *path = file->f_path;
1796 path_get(&file->f_path);
1797 }
1798 if (info)
1799 snprintf(info, PROC_FDINFO_MAX,
1800 "pos:\t%lli\n"
1801 "flags:\t0%o\n",
1802 (long long) file->f_pos,
1803 f_flags);
1804 spin_unlock(&files->file_lock);
1805 put_files_struct(files);
1806 return 0;
99f89551 1807 }
5e442a49
LT		 1808 spin_unlock(&files->file_lock);
1809 put_files_struct(files);
1810 }
1811 return -ENOENT;
99f89551
EB		 1812}
1813
7773fbc5 1814static int proc_fd_link(struct dentry *dentry, struct path *path)
27932742 1815{
7773fbc5 1816 return proc_fd_info(dentry->d_inode, path, NULL);
27932742
MS		 1817}
1818
1da177e4
LT		 1819static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1820{
34286d66
NP		 1821 struct inode *inode;
1822 struct task_struct *task;
1823 int fd;
1da177e4 1824 struct files_struct *files;
c69e8d9c 1825 const struct cred *cred;
1da177e4 1826
34286d66
NP		 1827 if (nd && nd->flags & LOOKUP_RCU)
1828 return -ECHILD;
1829
1830 inode = dentry->d_inode;
1831 task = get_proc_task(inode);
1832 fd = proc_fd(inode);
1833
99f89551
EB		 1834 if (task) {
1835 files = get_files_struct(task);
1836 if (files) {
1837 rcu_read_lock();
1838 if (fcheck_files(files, fd)) {
1839 rcu_read_unlock();
1840 put_files_struct(files);
1841 if (task_dumpable(task)) {
c69e8d9c
DH		 1842 rcu_read_lock();
1843 cred = __task_cred(task);
1844 inode->i_uid = cred->euid;
1845 inode->i_gid = cred->egid;
1846 rcu_read_unlock();
99f89551
EB		 1847 } else {
1848 inode->i_uid = 0;
1849 inode->i_gid = 0;
1850 }
9ee8ab9f 1851 inode->i_mode &= ~(S_ISUID | S_ISGID);
99f89551
EB		 1852 security_task_to_inode(task, inode);
1853 put_task_struct(task);
1854 return 1;
1855 }
b835996f 1856 rcu_read_unlock();
1da177e4 1857 put_files_struct(files);
1da177e4 1858 }
99f89551 1859 put_task_struct(task);
1da177e4
LT		 1860 }
1861 d_drop(dentry);
1862 return 0;
1863}
1864
d72f71eb 1865static const struct dentry_operations tid_fd_dentry_operations =
1da177e4
LT		 1866{
1867 .d_revalidate = tid_fd_revalidate,
1868 .d_delete = pid_delete_dentry,
1869};
1870
444ceed8 1871static struct dentry *proc_fd_instantiate(struct inode *dir,
c5141e6d 1872 struct dentry *dentry, struct task_struct *task, const void *ptr)
1da177e4 1873{
c5141e6d 1874 unsigned fd = *(const unsigned *)ptr;
444ceed8
EB		 1875 struct file *file;
1876 struct files_struct *files;
1877 struct inode *inode;
1878 struct proc_inode *ei;
1879 struct dentry *error = ERR_PTR(-ENOENT);
1da177e4 1880
61a28784 1881 inode = proc_pid_make_inode(dir->i_sb, task);
1da177e4
LT		 1882 if (!inode)
1883 goto out;
1884 ei = PROC_I(inode);
aed7a6c4 1885 ei->fd = fd;
1da177e4
LT		 1886 files = get_files_struct(task);
1887 if (!files)
444ceed8 1888 goto out_iput;
1da177e4 1889 inode->i_mode = S_IFLNK;
ca99c1da
DS		 1890
1891 /*
1892 * We are not taking a ref to the file structure, so we must
1893 * hold ->file_lock.
1894 */
1895 spin_lock(&files->file_lock);
1da177e4
LT		 1896 file = fcheck_files(files, fd);
1897 if (!file)
444ceed8 1898 goto out_unlock;
aeb5d727 1899 if (file->f_mode & FMODE_READ)
1da177e4 1900 inode->i_mode |= S_IRUSR | S_IXUSR;
aeb5d727 1901 if (file->f_mode & FMODE_WRITE)
1da177e4 1902 inode->i_mode |= S_IWUSR | S_IXUSR;
ca99c1da 1903 spin_unlock(&files->file_lock);
1da177e4 1904 put_files_struct(files);
444ceed8 1905
5e442a49 1906 inode->i_op = &proc_pid_link_inode_operations;
1da177e4
LT		 1907 inode->i_size = 64;
1908 ei->op.proc_get_link = proc_fd_link;
fb045adb 1909 d_set_d_op(dentry, &tid_fd_dentry_operations);
1da177e4 1910 d_add(dentry, inode);
cd6a3ce9
EB		 1911 /* Close the race of the process dying before we return the dentry */
1912 if (tid_fd_revalidate(dentry, NULL))
444ceed8 1913 error = NULL;
1da177e4 1914
444ceed8
EB		 1915 out:
1916 return error;
1917out_unlock:
ca99c1da 1918 spin_unlock(&files->file_lock);
1da177e4 1919 put_files_struct(files);
444ceed8 1920out_iput:
1da177e4 1921 iput(inode);
cd6a3ce9 1922 goto out;
1da177e4
LT		 1923}
1924
27932742
MS		 1925static struct dentry *proc_lookupfd_common(struct inode *dir,
1926 struct dentry *dentry,
1927 instantiate_t instantiate)
444ceed8
EB		 1928{
1929 struct task_struct *task = get_proc_task(dir);
1930 unsigned fd = name_to_int(dentry);
1931 struct dentry *result = ERR_PTR(-ENOENT);
1932
1933 if (!task)
1934 goto out_no_task;
1935 if (fd == ~0U)
1936 goto out;
1937
27932742 1938 result = instantiate(dir, dentry, task, &fd);
444ceed8
EB		 1939out:
1940 put_task_struct(task);
1941out_no_task:
1942 return result;
1943}
1944
27932742
MS		 1945static int proc_readfd_common(struct file * filp, void * dirent,
1946 filldir_t filldir, instantiate_t instantiate)
28a6d671 1947{
2fddfeef 1948 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 1949 struct inode *inode = dentry->d_inode;
1950 struct task_struct *p = get_proc_task(inode);
457c2510 1951 unsigned int fd, ino;
28a6d671 1952 int retval;
28a6d671 1953 struct files_struct * files;
1da177e4 1954
28a6d671
EB		 1955 retval = -ENOENT;
1956 if (!p)
1957 goto out_no_task;
1958 retval = 0;
28a6d671
EB		 1959
1960 fd = filp->f_pos;
1961 switch (fd) {
1962 case 0:
1963 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
5e442a49 1964 goto out;
28a6d671
EB		 1965 filp->f_pos++;
1966 case 1:
1967 ino = parent_ino(dentry);
1968 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
5e442a49 1969 goto out;
28a6d671
EB		 1970 filp->f_pos++;
1971 default:
1972 files = get_files_struct(p);
1973 if (!files)
5e442a49 1974 goto out;
28a6d671 1975 rcu_read_lock();
28a6d671 1976 for (fd = filp->f_pos-2;
9b4f526c 1977 fd < files_fdtable(files)->max_fds;
28a6d671 1978 fd++, filp->f_pos++) {
27932742
MS		 1979 char name[PROC_NUMBUF];
1980 int len;
28a6d671
EB		 1981
1982 if (!fcheck_files(files, fd))
1983 continue;
1984 rcu_read_unlock();
1985
27932742
MS		 1986 len = snprintf(name, sizeof(name), "%d", fd);
1987 if (proc_fill_cache(filp, dirent, filldir,
1988 name, len, instantiate,
1989 p, &fd) < 0) {
28a6d671
EB		 1990 rcu_read_lock();
1991 break;
1992 }
1993 rcu_read_lock();
1994 }
1995 rcu_read_unlock();
1996 put_files_struct(files);
1997 }
1998out:
1999 put_task_struct(p);
2000out_no_task:
2001 return retval;
2002}
2003
27932742
MS		 2004static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
2005 struct nameidata *nd)
2006{
2007 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
2008}
2009
2010static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
2011{
2012 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
2013}
2014
2015static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
2016 size_t len, loff_t *ppos)
2017{
2018 char tmp[PROC_FDINFO_MAX];
3dcd25f3 2019 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
27932742
MS		 2020 if (!err)
2021 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
2022 return err;
2023}
2024
2025static const struct file_operations proc_fdinfo_file_operations = {
87df8424 2026 .open = nonseekable_open,
27932742 2027 .read = proc_fdinfo_read,
6038f373 2028 .llseek = no_llseek,
27932742
MS		 2029};
2030
00977a59 2031static const struct file_operations proc_fd_operations = {
28a6d671
EB		 2032 .read = generic_read_dir,
2033 .readdir = proc_readfd,
6038f373 2034 .llseek = default_llseek,
1da177e4
LT		 2035};
2036
640708a2
PE		 2037#ifdef CONFIG_CHECKPOINT_RESTORE
2038
2039/*
2040 * dname_to_vma_addr - maps a dentry name into two unsigned longs
2041 * which represent vma start and end addresses.
2042 */
2043static int dname_to_vma_addr(struct dentry *dentry,
2044 unsigned long *start, unsigned long *end)
2045{
2046 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
2047 return -EINVAL;
2048
2049 return 0;
2050}
2051
2052static int map_files_d_revalidate(struct dentry *dentry, struct nameidata *nd)
2053{
2054 unsigned long vm_start, vm_end;
2055 bool exact_vma_exists = false;
2056 struct mm_struct *mm = NULL;
2057 struct task_struct *task;
2058 const struct cred *cred;
2059 struct inode *inode;
2060 int status = 0;
2061
2062 if (nd && nd->flags & LOOKUP_RCU)
2063 return -ECHILD;
2064
2065 if (!capable(CAP_SYS_ADMIN)) {
2066 status = -EACCES;
2067 goto out_notask;
2068 }
2069
2070 inode = dentry->d_inode;
2071 task = get_proc_task(inode);
2072 if (!task)
2073 goto out_notask;
2074
2075 if (!ptrace_may_access(task, PTRACE_MODE_READ))
2076 goto out;
2077
2078 mm = get_task_mm(task);
2079 if (!mm)
2080 goto out;
2081
2082 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2083 down_read(&mm->mmap_sem);
2084 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
2085 up_read(&mm->mmap_sem);
2086 }
2087
2088 mmput(mm);
2089
2090 if (exact_vma_exists) {
2091 if (task_dumpable(task)) {
2092 rcu_read_lock();
2093 cred = __task_cred(task);
2094 inode->i_uid = cred->euid;
2095 inode->i_gid = cred->egid;
2096 rcu_read_unlock();
2097 } else {
2098 inode->i_uid = 0;
2099 inode->i_gid = 0;
2100 }
2101 security_task_to_inode(task, inode);
2102 status = 1;
2103 }
2104
2105out:
2106 put_task_struct(task);
2107
2108out_notask:
2109 if (status <= 0)
2110 d_drop(dentry);
2111
2112 return status;
2113}
2114
2115static const struct dentry_operations tid_map_files_dentry_operations = {
2116 .d_revalidate = map_files_d_revalidate,
2117 .d_delete = pid_delete_dentry,
2118};
2119
2120static int proc_map_files_get_link(struct dentry *dentry, struct path *path)
2121{
2122 unsigned long vm_start, vm_end;
2123 struct vm_area_struct *vma;
2124 struct task_struct *task;
2125 struct mm_struct *mm;
2126 int rc;
2127
2128 rc = -ENOENT;
2129 task = get_proc_task(dentry->d_inode);
2130 if (!task)
2131 goto out;
2132
2133 mm = get_task_mm(task);
2134 put_task_struct(task);
2135 if (!mm)
2136 goto out;
2137
2138 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2139 if (rc)
2140 goto out_mmput;
2141
2142 down_read(&mm->mmap_sem);
2143 vma = find_exact_vma(mm, vm_start, vm_end);
2144 if (vma && vma->vm_file) {
2145 *path = vma->vm_file->f_path;
2146 path_get(path);
2147 rc = 0;
2148 }
2149 up_read(&mm->mmap_sem);
2150
2151out_mmput:
2152 mmput(mm);
2153out:
2154 return rc;
2155}
2156
2157struct map_files_info {
2158 struct file *file;
2159 unsigned long len;
2160 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
2161};
2162
2163static struct dentry *
2164proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2165 struct task_struct *task, const void *ptr)
2166{
2167 const struct file *file = ptr;
2168 struct proc_inode *ei;
2169 struct inode *inode;
2170
2171 if (!file)
2172 return ERR_PTR(-ENOENT);
2173
2174 inode = proc_pid_make_inode(dir->i_sb, task);
2175 if (!inode)
2176 return ERR_PTR(-ENOENT);
2177
2178 ei = PROC_I(inode);
2179 ei->op.proc_get_link = proc_map_files_get_link;
2180
2181 inode->i_op = &proc_pid_link_inode_operations;
2182 inode->i_size = 64;
2183 inode->i_mode = S_IFLNK;
2184
2185 if (file->f_mode & FMODE_READ)
2186 inode->i_mode |= S_IRUSR;
2187 if (file->f_mode & FMODE_WRITE)
2188 inode->i_mode |= S_IWUSR;
2189
2190 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2191 d_add(dentry, inode);
2192
2193 return NULL;
2194}
2195
2196static struct dentry *proc_map_files_lookup(struct inode *dir,
2197 struct dentry *dentry, struct nameidata *nd)
2198{
2199 unsigned long vm_start, vm_end;
2200 struct vm_area_struct *vma;
2201 struct task_struct *task;
2202 struct dentry *result;
2203 struct mm_struct *mm;
2204
2205 result = ERR_PTR(-EACCES);
2206 if (!capable(CAP_SYS_ADMIN))
2207 goto out;
2208
2209 result = ERR_PTR(-ENOENT);
2210 task = get_proc_task(dir);
2211 if (!task)
2212 goto out;
2213
2214 result = ERR_PTR(-EACCES);
2215 if (lock_trace(task))
2216 goto out_put_task;
2217
2218 result = ERR_PTR(-ENOENT);
2219 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2220 goto out_unlock;
2221
2222 mm = get_task_mm(task);
2223 if (!mm)
2224 goto out_unlock;
2225
2226 down_read(&mm->mmap_sem);
2227 vma = find_exact_vma(mm, vm_start, vm_end);
2228 if (!vma)
2229 goto out_no_vma;
2230
2231 result = proc_map_files_instantiate(dir, dentry, task, vma->vm_file);
2232
2233out_no_vma:
2234 up_read(&mm->mmap_sem);
2235 mmput(mm);
2236out_unlock:
2237 unlock_trace(task);
2238out_put_task:
2239 put_task_struct(task);
2240out:
2241 return result;
2242}
2243
2244static const struct inode_operations proc_map_files_inode_operations = {
2245 .lookup = proc_map_files_lookup,
2246 .permission = proc_fd_permission,
2247 .setattr = proc_setattr,
2248};
2249
2250static int
2251proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
2252{
2253 struct dentry *dentry = filp->f_path.dentry;
2254 struct inode *inode = dentry->d_inode;
2255 struct vm_area_struct *vma;
2256 struct task_struct *task;
2257 struct mm_struct *mm;
2258 ino_t ino;
2259 int ret;
2260
2261 ret = -EACCES;
2262 if (!capable(CAP_SYS_ADMIN))
2263 goto out;
2264
2265 ret = -ENOENT;
2266 task = get_proc_task(inode);
2267 if (!task)
2268 goto out;
2269
2270 ret = -EACCES;
2271 if (lock_trace(task))
2272 goto out_put_task;
2273
2274 ret = 0;
2275 switch (filp->f_pos) {
2276 case 0:
2277 ino = inode->i_ino;
2278 if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0)
2279 goto out_unlock;
2280 filp->f_pos++;
2281 case 1:
2282 ino = parent_ino(dentry);
2283 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2284 goto out_unlock;
2285 filp->f_pos++;
2286 default:
2287 {
2288 unsigned long nr_files, pos, i;
2289 struct flex_array *fa = NULL;
2290 struct map_files_info info;
2291 struct map_files_info *p;
2292
2293 mm = get_task_mm(task);
2294 if (!mm)
2295 goto out_unlock;
2296 down_read(&mm->mmap_sem);
2297
2298 nr_files = 0;
2299
2300 /*
2301 * We need two passes here:
2302 *
2303 * 1) Collect vmas of mapped files with mmap_sem taken
2304 * 2) Release mmap_sem and instantiate entries
2305 *
2306 * otherwise we get lockdep complained, since filldir()
2307 * routine might require mmap_sem taken in might_fault().
2308 */
2309
2310 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2311 if (vma->vm_file && ++pos > filp->f_pos)
2312 nr_files++;
2313 }
2314
2315 if (nr_files) {
2316 fa = flex_array_alloc(sizeof(info), nr_files,
2317 GFP_KERNEL);
2318 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2319 GFP_KERNEL)) {
2320 ret = -ENOMEM;
2321 if (fa)
2322 flex_array_free(fa);
2323 up_read(&mm->mmap_sem);
2324 mmput(mm);
2325 goto out_unlock;
2326 }
2327 for (i = 0, vma = mm->mmap, pos = 2; vma;
2328 vma = vma->vm_next) {
2329 if (!vma->vm_file)
2330 continue;
2331 if (++pos <= filp->f_pos)
2332 continue;
2333
2334 get_file(vma->vm_file);
2335 info.file = vma->vm_file;
2336 info.len = snprintf(info.name,
2337 sizeof(info.name), "%lx-%lx",
2338 vma->vm_start, vma->vm_end);
2339 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2340 BUG();
2341 }
2342 }
2343 up_read(&mm->mmap_sem);
2344
2345 for (i = 0; i < nr_files; i++) {
2346 p = flex_array_get(fa, i);
2347 ret = proc_fill_cache(filp, dirent, filldir,
2348 p->name, p->len,
2349 proc_map_files_instantiate,
2350 task, p->file);
2351 if (ret)
2352 break;
2353 filp->f_pos++;
2354 fput(p->file);
2355 }
2356 for (; i < nr_files; i++) {
2357 /*
2358 * In case of error don't forget
2359 * to put rest of file refs.
2360 */
2361 p = flex_array_get(fa, i);
2362 fput(p->file);
2363 }
2364 if (fa)
2365 flex_array_free(fa);
2366 mmput(mm);
2367 }
2368 }
2369
2370out_unlock:
2371 unlock_trace(task);
2372out_put_task:
2373 put_task_struct(task);
2374out:
2375 return ret;
2376}
2377
2378static const struct file_operations proc_map_files_operations = {
2379 .read = generic_read_dir,
2380 .readdir = proc_map_files_readdir,
2381 .llseek = default_llseek,
2382};
2383
2384#endif /* CONFIG_CHECKPOINT_RESTORE */
2385
8948e11f
AD		 2386/*
2387 * /proc/pid/fd needs a special permission handler so that a process can still
2388 * access /proc/self/fd after it has executed a setuid().
2389 */
10556cb2 2390static int proc_fd_permission(struct inode *inode, int mask)
8948e11f 2391{
2830ba7f 2392 int rv = generic_permission(inode, mask);
8948e11f
AD		 2393 if (rv == 0)
2394 return 0;
2395 if (task_pid(current) == proc_pid(inode))
2396 rv = 0;
2397 return rv;
2398}
2399
1da177e4
LT		 2400/*
2401 * proc directories can do almost nothing..
2402 */
c5ef1c42 2403static const struct inode_operations proc_fd_inode_operations = {
1da177e4 2404 .lookup = proc_lookupfd,
8948e11f 2405 .permission = proc_fd_permission,
6d76fa58 2406 .setattr = proc_setattr,
1da177e4
LT		 2407};
2408
27932742
MS		 2409static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2410 struct dentry *dentry, struct task_struct *task, const void *ptr)
2411{
2412 unsigned fd = *(unsigned *)ptr;
2413 struct inode *inode;
2414 struct proc_inode *ei;
2415 struct dentry *error = ERR_PTR(-ENOENT);
2416
2417 inode = proc_pid_make_inode(dir->i_sb, task);
2418 if (!inode)
2419 goto out;
2420 ei = PROC_I(inode);
2421 ei->fd = fd;
2422 inode->i_mode = S_IFREG | S_IRUSR;
2423 inode->i_fop = &proc_fdinfo_file_operations;
fb045adb 2424 d_set_d_op(dentry, &tid_fd_dentry_operations);
27932742
MS		 2425 d_add(dentry, inode);
2426 /* Close the race of the process dying before we return the dentry */
2427 if (tid_fd_revalidate(dentry, NULL))
2428 error = NULL;
2429
2430 out:
2431 return error;
2432}
2433
2434static struct dentry *proc_lookupfdinfo(struct inode *dir,
2435 struct dentry *dentry,
2436 struct nameidata *nd)
2437{
2438 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2439}
2440
2441static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2442{
2443 return proc_readfd_common(filp, dirent, filldir,
2444 proc_fdinfo_instantiate);
2445}
2446
2447static const struct file_operations proc_fdinfo_operations = {
2448 .read = generic_read_dir,
2449 .readdir = proc_readfdinfo,
6038f373 2450 .llseek = default_llseek,
27932742
MS		 2451};
2452
2453/*
2454 * proc directories can do almost nothing..
2455 */
2456static const struct inode_operations proc_fdinfo_inode_operations = {
2457 .lookup = proc_lookupfdinfo,
2458 .setattr = proc_setattr,
2459};
2460
2461
444ceed8 2462static struct dentry *proc_pident_instantiate(struct inode *dir,
c5141e6d 2463 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2464{
c5141e6d 2465 const struct pid_entry *p = ptr;
444ceed8
EB		 2466 struct inode *inode;
2467 struct proc_inode *ei;
bd6daba9 2468 struct dentry *error = ERR_PTR(-ENOENT);
444ceed8 2469
61a28784 2470 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2471 if (!inode)
2472 goto out;
2473
2474 ei = PROC_I(inode);
2475 inode->i_mode = p->mode;
2476 if (S_ISDIR(inode->i_mode))
bfe86848 2477 set_nlink(inode, 2); /* Use getattr to fix if necessary */
444ceed8
EB		 2478 if (p->iop)
2479 inode->i_op = p->iop;
2480 if (p->fop)
2481 inode->i_fop = p->fop;
2482 ei->op = p->op;
fb045adb 2483 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2484 d_add(dentry, inode);
2485 /* Close the race of the process dying before we return the dentry */
2486 if (pid_revalidate(dentry, NULL))
2487 error = NULL;
2488out:
2489 return error;
2490}
2491
1da177e4
LT		 2492static struct dentry *proc_pident_lookup(struct inode *dir,
2493 struct dentry *dentry,
c5141e6d 2494 const struct pid_entry *ents,
7bcd6b0e 2495 unsigned int nents)
1da177e4 2496{
cd6a3ce9 2497 struct dentry *error;
99f89551 2498 struct task_struct *task = get_proc_task(dir);
c5141e6d 2499 const struct pid_entry *p, *last;
1da177e4 2500
cd6a3ce9 2501 error = ERR_PTR(-ENOENT);
1da177e4 2502
99f89551
EB		 2503 if (!task)
2504 goto out_no_task;
1da177e4 2505
20cdc894
EB		 2506 /*
2507 * Yes, it does not scale. And it should not. Don't add
2508 * new entries into /proc/<tgid>/ without very good reasons.
2509 */
7bcd6b0e
EB		 2510 last = &ents[nents - 1];
2511 for (p = ents; p <= last; p++) {
1da177e4
LT		 2512 if (p->len != dentry->d_name.len)
2513 continue;
2514 if (!memcmp(dentry->d_name.name, p->name, p->len))
2515 break;
2516 }
7bcd6b0e 2517 if (p > last)
1da177e4
LT		 2518 goto out;
2519
444ceed8 2520 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2521out:
99f89551
EB		 2522 put_task_struct(task);
2523out_no_task:
cd6a3ce9 2524 return error;
1da177e4
LT		 2525}
2526
c5141e6d
ED		 2527static int proc_pident_fill_cache(struct file *filp, void *dirent,
2528 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2529{
2530 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2531 proc_pident_instantiate, task, p);
2532}
2533
28a6d671
EB		 2534static int proc_pident_readdir(struct file *filp,
2535 void *dirent, filldir_t filldir,
c5141e6d 2536 const struct pid_entry *ents, unsigned int nents)
28a6d671
EB		 2537{
2538 int i;
2fddfeef 2539 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2540 struct inode *inode = dentry->d_inode;
2541 struct task_struct *task = get_proc_task(inode);
c5141e6d 2542 const struct pid_entry *p, *last;
28a6d671
EB		 2543 ino_t ino;
2544 int ret;
2545
2546 ret = -ENOENT;
2547 if (!task)
61a28784 2548 goto out_no_task;
28a6d671
EB		 2549
2550 ret = 0;
28a6d671
EB		 2551 i = filp->f_pos;
2552 switch (i) {
2553 case 0:
2554 ino = inode->i_ino;
2555 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2556 goto out;
2557 i++;
2558 filp->f_pos++;
2559 /* fall through */
2560 case 1:
2561 ino = parent_ino(dentry);
2562 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2563 goto out;
2564 i++;
2565 filp->f_pos++;
2566 /* fall through */
2567 default:
2568 i -= 2;
2569 if (i >= nents) {
2570 ret = 1;
2571 goto out;
2572 }
2573 p = ents + i;
7bcd6b0e
EB		 2574 last = &ents[nents - 1];
2575 while (p <= last) {
61a28784 2576 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
28a6d671
EB		 2577 goto out;
2578 filp->f_pos++;
2579 p++;
2580 }
2581 }
2582
2583 ret = 1;
2584out:
61a28784
EB		 2585 put_task_struct(task);
2586out_no_task:
28a6d671 2587 return ret;
1da177e4
LT		 2588}
2589
28a6d671
EB		 2590#ifdef CONFIG_SECURITY
2591static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2592 size_t count, loff_t *ppos)
2593{
2fddfeef 2594 struct inode * inode = file->f_path.dentry->d_inode;
04ff9708 2595 char *p = NULL;
28a6d671
EB		 2596 ssize_t length;
2597 struct task_struct *task = get_proc_task(inode);
2598
28a6d671 2599 if (!task)
04ff9708 2600 return -ESRCH;
28a6d671
EB		 2601
2602 length = security_getprocattr(task,
2fddfeef 2603 (char*)file->f_path.dentry->d_name.name,
04ff9708 2604 &p);
28a6d671 2605 put_task_struct(task);
04ff9708
AV		 2606 if (length > 0)
2607 length = simple_read_from_buffer(buf, count, ppos, p, length);
2608 kfree(p);
28a6d671 2609 return length;
1da177e4
LT		 2610}
2611
28a6d671
EB		 2612static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2613 size_t count, loff_t *ppos)
2614{
2fddfeef 2615 struct inode * inode = file->f_path.dentry->d_inode;
28a6d671
EB		 2616 char *page;
2617 ssize_t length;
2618 struct task_struct *task = get_proc_task(inode);
2619
2620 length = -ESRCH;
2621 if (!task)
2622 goto out_no_task;
2623 if (count > PAGE_SIZE)
2624 count = PAGE_SIZE;
2625
2626 /* No partial writes. */
2627 length = -EINVAL;
2628 if (*ppos != 0)
2629 goto out;
2630
2631 length = -ENOMEM;
e12ba74d 2632 page = (char*)__get_free_page(GFP_TEMPORARY);
28a6d671
EB		 2633 if (!page)
2634 goto out;
2635
2636 length = -EFAULT;
2637 if (copy_from_user(page, buf, count))
2638 goto out_free;
2639
107db7c7 2640 /* Guard against adverse ptrace interaction */
9b1bf12d 2641 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2642 if (length < 0)
2643 goto out_free;
2644
28a6d671 2645 length = security_setprocattr(task,
2fddfeef 2646 (char*)file->f_path.dentry->d_name.name,
28a6d671 2647 (void*)page, count);
9b1bf12d 2648 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671
EB		 2649out_free:
2650 free_page((unsigned long) page);
2651out:
2652 put_task_struct(task);
2653out_no_task:
2654 return length;
2655}
2656
00977a59 2657static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2658 .read = proc_pid_attr_read,
2659 .write = proc_pid_attr_write,
87df8424 2660 .llseek = generic_file_llseek,
28a6d671
EB		 2661};
2662
c5141e6d 2663static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2664 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2665 REG("prev", S_IRUGO, proc_pid_attr_operations),
2666 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2667 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2668 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2669 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2670};
2671
72d9dcfc 2672static int proc_attr_dir_readdir(struct file * filp,
28a6d671
EB		 2673 void * dirent, filldir_t filldir)
2674{
2675 return proc_pident_readdir(filp,dirent,filldir,
72d9dcfc 2676 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2677}
2678
00977a59 2679static const struct file_operations proc_attr_dir_operations = {
1da177e4 2680 .read = generic_read_dir,
72d9dcfc 2681 .readdir = proc_attr_dir_readdir,
6038f373 2682 .llseek = default_llseek,
1da177e4
LT		 2683};
2684
72d9dcfc 2685static struct dentry *proc_attr_dir_lookup(struct inode *dir,
28a6d671
EB		 2686 struct dentry *dentry, struct nameidata *nd)
2687{
7bcd6b0e
EB		 2688 return proc_pident_lookup(dir, dentry,
2689 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2690}
2691
c5ef1c42 2692static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2693 .lookup = proc_attr_dir_lookup,
99f89551 2694 .getattr = pid_getattr,
6d76fa58 2695 .setattr = proc_setattr,
1da177e4
LT		 2696};
2697
28a6d671
EB		 2698#endif
2699
698ba7b5 2700#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2701static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2702 size_t count, loff_t *ppos)
2703{
2704 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2705 struct mm_struct *mm;
2706 char buffer[PROC_NUMBUF];
2707 size_t len;
2708 int ret;
2709
2710 if (!task)
2711 return -ESRCH;
2712
2713 ret = 0;
2714 mm = get_task_mm(task);
2715 if (mm) {
2716 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2717 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2718 MMF_DUMP_FILTER_SHIFT));
2719 mmput(mm);
2720 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2721 }
2722
2723 put_task_struct(task);
2724
2725 return ret;
2726}
2727
2728static ssize_t proc_coredump_filter_write(struct file *file,
2729 const char __user *buf,
2730 size_t count,
2731 loff_t *ppos)
2732{
2733 struct task_struct *task;
2734 struct mm_struct *mm;
2735 char buffer[PROC_NUMBUF], *end;
2736 unsigned int val;
2737 int ret;
2738 int i;
2739 unsigned long mask;
2740
2741 ret = -EFAULT;
2742 memset(buffer, 0, sizeof(buffer));
2743 if (count > sizeof(buffer) - 1)
2744 count = sizeof(buffer) - 1;
2745 if (copy_from_user(buffer, buf, count))
2746 goto out_no_task;
2747
2748 ret = -EINVAL;
2749 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2750 if (*end == '\n')
2751 end++;
2752 if (end - buffer == 0)
2753 goto out_no_task;
2754
2755 ret = -ESRCH;
2756 task = get_proc_task(file->f_dentry->d_inode);
2757 if (!task)
2758 goto out_no_task;
2759
2760 ret = end - buffer;
2761 mm = get_task_mm(task);
2762 if (!mm)
2763 goto out_no_mm;
2764
2765 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2766 if (val & mask)
2767 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2768 else
2769 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2770 }
2771
2772 mmput(mm);
2773 out_no_mm:
2774 put_task_struct(task);
2775 out_no_task:
2776 return ret;
2777}
2778
2779static const struct file_operations proc_coredump_filter_operations = {
2780 .read = proc_coredump_filter_read,
2781 .write = proc_coredump_filter_write,
87df8424 2782 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2783};
2784#endif
2785
28a6d671
EB		 2786/*
2787 * /proc/self:
2788 */
2789static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2790 int buflen)
2791{
488e5bc4 2792 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2793 pid_t tgid = task_tgid_nr_ns(current, ns);
28a6d671 2794 char tmp[PROC_NUMBUF];
b55fcb22 2795 if (!tgid)
488e5bc4 2796 return -ENOENT;
b55fcb22 2797 sprintf(tmp, "%d", tgid);
28a6d671
EB		 2798 return vfs_readlink(dentry,buffer,buflen,tmp);
2799}
2800
2801static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2802{
488e5bc4 2803 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2804 pid_t tgid = task_tgid_nr_ns(current, ns);
7fee4868
AV		 2805 char *name = ERR_PTR(-ENOENT);
2806 if (tgid) {
2807 name = __getname();
2808 if (!name)
2809 name = ERR_PTR(-ENOMEM);
2810 else
2811 sprintf(name, "%d", tgid);
2812 }
2813 nd_set_link(nd, name);
2814 return NULL;
2815}
2816
2817static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2818 void *cookie)
2819{
2820 char *s = nd_get_link(nd);
2821 if (!IS_ERR(s))
2822 __putname(s);
28a6d671
EB		 2823}
2824
c5ef1c42 2825static const struct inode_operations proc_self_inode_operations = {
28a6d671
EB		 2826 .readlink = proc_self_readlink,
2827 .follow_link = proc_self_follow_link,
7fee4868 2828 .put_link = proc_self_put_link,
28a6d671
EB		 2829};
2830
801199ce
EB		 2831/*
2832 * proc base
2833 *
2834 * These are the directory entries in the root directory of /proc
2835 * that properly belong to the /proc filesystem, as they describe
2836 * describe something that is process related.
2837 */
c5141e6d 2838static const struct pid_entry proc_base_stuff[] = {
61a28784 2839 NOD("self", S_IFLNK|S_IRWXUGO,
801199ce 2840 &proc_self_inode_operations, NULL, {}),
801199ce
EB		 2841};
2842
444ceed8 2843static struct dentry *proc_base_instantiate(struct inode *dir,
c5141e6d 2844 struct dentry *dentry, struct task_struct *task, const void *ptr)
801199ce 2845{
c5141e6d 2846 const struct pid_entry *p = ptr;
801199ce 2847 struct inode *inode;
801199ce 2848 struct proc_inode *ei;
73d36460 2849 struct dentry *error;
801199ce
EB		 2850
2851 /* Allocate the inode */
2852 error = ERR_PTR(-ENOMEM);
2853 inode = new_inode(dir->i_sb);
2854 if (!inode)
2855 goto out;
2856
2857 /* Initialize the inode */
2858 ei = PROC_I(inode);
85fe4025 2859 inode->i_ino = get_next_ino();
801199ce 2860 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
801199ce
EB		 2861
2862 /*
2863 * grab the reference to the task.
2864 */
1a657f78 2865 ei->pid = get_task_pid(task, PIDTYPE_PID);
801199ce
EB		 2866 if (!ei->pid)
2867 goto out_iput;
2868
801199ce
EB		 2869 inode->i_mode = p->mode;
2870 if (S_ISDIR(inode->i_mode))
bfe86848 2871 set_nlink(inode, 2);
801199ce
EB		 2872 if (S_ISLNK(inode->i_mode))
2873 inode->i_size = 64;
2874 if (p->iop)
2875 inode->i_op = p->iop;
2876 if (p->fop)
2877 inode->i_fop = p->fop;
2878 ei->op = p->op;
801199ce
EB		 2879 d_add(dentry, inode);
2880 error = NULL;
2881out:
801199ce
EB		 2882 return error;
2883out_iput:
2884 iput(inode);
2885 goto out;
2886}
2887
444ceed8
EB		 2888static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2889{
2890 struct dentry *error;
2891 struct task_struct *task = get_proc_task(dir);
c5141e6d 2892 const struct pid_entry *p, *last;
444ceed8
EB		 2893
2894 error = ERR_PTR(-ENOENT);
2895
2896 if (!task)
2897 goto out_no_task;
2898
2899 /* Lookup the directory entry */
7bcd6b0e
EB		 2900 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2901 for (p = proc_base_stuff; p <= last; p++) {
444ceed8
EB		 2902 if (p->len != dentry->d_name.len)
2903 continue;
2904 if (!memcmp(dentry->d_name.name, p->name, p->len))
2905 break;
2906 }
7bcd6b0e 2907 if (p > last)
444ceed8
EB		 2908 goto out;
2909
2910 error = proc_base_instantiate(dir, dentry, task, p);
2911
2912out:
2913 put_task_struct(task);
2914out_no_task:
2915 return error;
2916}
2917
c5141e6d
ED		 2918static int proc_base_fill_cache(struct file *filp, void *dirent,
2919 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2920{
2921 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2922 proc_base_instantiate, task, p);
2923}
2924
aba76fdb 2925#ifdef CONFIG_TASK_IO_ACCOUNTING
297c5d92
AR		 2926static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2927{
940389b8 2928 struct task_io_accounting acct = task->ioac;
5995477a 2929 unsigned long flags;
293eb1e7 2930 int result;
5995477a 2931
293eb1e7
VK		 2932 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2933 if (result)
2934 return result;
2935
2936 if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
2937 result = -EACCES;
2938 goto out_unlock;
2939 }
1d1221f3 2940
5995477a
AR		 2941 if (whole && lock_task_sighand(task, &flags)) {
2942 struct task_struct *t = task;
2943
2944 task_io_accounting_add(&acct, &task->signal->ioac);
2945 while_each_thread(task, t)
2946 task_io_accounting_add(&acct, &t->ioac);
2947
2948 unlock_task_sighand(task, &flags);
297c5d92 2949 }
293eb1e7 2950 result = sprintf(buffer,
aba76fdb
AM		 2951 "rchar: %llu\n"
2952 "wchar: %llu\n"
2953 "syscr: %llu\n"
2954 "syscw: %llu\n"
2955 "read_bytes: %llu\n"
2956 "write_bytes: %llu\n"
2957 "cancelled_write_bytes: %llu\n",
7c44319d
AB		 2958 (unsigned long long)acct.rchar,
2959 (unsigned long long)acct.wchar,
2960 (unsigned long long)acct.syscr,
2961 (unsigned long long)acct.syscw,
2962 (unsigned long long)acct.read_bytes,
2963 (unsigned long long)acct.write_bytes,
2964 (unsigned long long)acct.cancelled_write_bytes);
293eb1e7
VK		 2965out_unlock:
2966 mutex_unlock(&task->signal->cred_guard_mutex);
2967 return result;
297c5d92
AR		 2968}
2969
2970static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2971{
2972 return do_io_accounting(task, buffer, 0);
aba76fdb 2973}
297c5d92
AR		 2974
2975static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2976{
2977 return do_io_accounting(task, buffer, 1);
2978}
2979#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2980
47830723
KC		 2981static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2982 struct pid *pid, struct task_struct *task)
2983{
a9712bc1
AV		 2984 int err = lock_trace(task);
2985 if (!err) {
2986 seq_printf(m, "%08x\n", task->personality);
2987 unlock_trace(task);
2988 }
2989 return err;
47830723
KC		 2990}
2991
28a6d671
EB		 2992/*
2993 * Thread groups
2994 */
00977a59 2995static const struct file_operations proc_task_operations;
c5ef1c42 2996static const struct inode_operations proc_task_inode_operations;
20cdc894 2997
c5141e6d 2998static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2999 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
3000 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
640708a2
PE		 3001#ifdef CONFIG_CHECKPOINT_RESTORE
3002 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
3003#endif
631f9c18 3004 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 3005 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
b2211a36 3006#ifdef CONFIG_NET
631f9c18 3007 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 3008#endif
631f9c18
AD		 3009 REG("environ", S_IRUSR, proc_environ_operations),
3010 INF("auxv", S_IRUSR, proc_pid_auxv),
3011 ONE("status", S_IRUGO, proc_pid_status),
a9712bc1 3012 ONE("personality", S_IRUGO, proc_pid_personality),
3036e7b4 3013 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3014#ifdef CONFIG_SCHED_DEBUG
631f9c18 3015 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
5091faa4
MG		 3016#endif
3017#ifdef CONFIG_SCHED_AUTOGROUP
3018 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
ebcb6734 3019#endif
4614a696 3020 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3021#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
a9712bc1 3022 INF("syscall", S_IRUGO, proc_pid_syscall),
43ae34cb 3023#endif
631f9c18
AD		 3024 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3025 ONE("stat", S_IRUGO, proc_tgid_stat),
3026 ONE("statm", S_IRUGO, proc_pid_statm),
3027 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3028#ifdef CONFIG_NUMA
631f9c18 3029 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3030#endif
631f9c18
AD		 3031 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3032 LNK("cwd", proc_cwd_link),
3033 LNK("root", proc_root_link),
3034 LNK("exe", proc_exe_link),
3035 REG("mounts", S_IRUGO, proc_mounts_operations),
3036 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3037 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 3038#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3039 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3040 REG("smaps", S_IRUGO, proc_smaps_operations),
ca6b0bf0 3041 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 3042#endif
3043#ifdef CONFIG_SECURITY
631f9c18 3044 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3045#endif
3046#ifdef CONFIG_KALLSYMS
631f9c18 3047 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3048#endif
2ec220e2 3049#ifdef CONFIG_STACKTRACE
a9712bc1 3050 ONE("stack", S_IRUGO, proc_pid_stack),
28a6d671
EB		 3051#endif
3052#ifdef CONFIG_SCHEDSTATS
631f9c18 3053 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3054#endif
9745512c 3055#ifdef CONFIG_LATENCYTOP
631f9c18 3056 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3057#endif
8793d854 3058#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3059 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3060#endif
3061#ifdef CONFIG_CGROUPS
631f9c18 3062 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3063#endif
631f9c18
AD		 3064 INF("oom_score", S_IRUGO, proc_oom_score),
3065 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3066 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3067#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 3068 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3069 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3070#endif
f4f154fd 3071#ifdef CONFIG_FAULT_INJECTION
631f9c18 3072 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3073#endif
698ba7b5 3074#ifdef CONFIG_ELF_CORE
631f9c18 3075 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 3076#endif
aba76fdb 3077#ifdef CONFIG_TASK_IO_ACCOUNTING
1d1221f3 3078 INF("io", S_IRUSR, proc_tgid_io_accounting),
aba76fdb 3079#endif
f133ecca
CM		 3080#ifdef CONFIG_HARDWALL
3081 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3082#endif
28a6d671 3083};
1da177e4 3084
28a6d671 3085static int proc_tgid_base_readdir(struct file * filp,
1da177e4
LT		 3086 void * dirent, filldir_t filldir)
3087{
3088 return proc_pident_readdir(filp,dirent,filldir,
28a6d671 3089 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 3090}
3091
00977a59 3092static const struct file_operations proc_tgid_base_operations = {
1da177e4 3093 .read = generic_read_dir,
28a6d671 3094 .readdir = proc_tgid_base_readdir,
6038f373 3095 .llseek = default_llseek,
1da177e4
LT		 3096};
3097
28a6d671 3098static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3099 return proc_pident_lookup(dir, dentry,
3100 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 3101}
3102
c5ef1c42 3103static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 3104 .lookup = proc_tgid_base_lookup,
99f89551 3105 .getattr = pid_getattr,
6d76fa58 3106 .setattr = proc_setattr,
0499680a 3107 .permission = proc_pid_permission,
1da177e4 3108};
1da177e4 3109
60347f67 3110static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 3111{
48e6484d 3112 struct dentry *dentry, *leader, *dir;
8578cea7 3113 char buf[PROC_NUMBUF];
48e6484d
EB		 3114 struct qstr name;
3115
3116 name.name = buf;
60347f67
PE		 3117 name.len = snprintf(buf, sizeof(buf), "%d", pid);
3118 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 3119 if (dentry) {
29f12ca3 3120 shrink_dcache_parent(dentry);
48e6484d
EB		 3121 d_drop(dentry);
3122 dput(dentry);
3123 }
1da177e4 3124
48e6484d 3125 name.name = buf;
60347f67
PE		 3126 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
3127 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 3128 if (!leader)
3129 goto out;
1da177e4 3130
48e6484d
EB		 3131 name.name = "task";
3132 name.len = strlen(name.name);
3133 dir = d_hash_and_lookup(leader, &name);
3134 if (!dir)
3135 goto out_put_leader;
3136
3137 name.name = buf;
60347f67 3138 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 3139 dentry = d_hash_and_lookup(dir, &name);
3140 if (dentry) {
3141 shrink_dcache_parent(dentry);
3142 d_drop(dentry);
3143 dput(dentry);
1da177e4 3144 }
48e6484d
EB		 3145
3146 dput(dir);
3147out_put_leader:
3148 dput(leader);
3149out:
3150 return;
1da177e4
LT		 3151}
3152
0895e91d
RD		 3153/**
3154 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3155 * @task: task that should be flushed.
3156 *
3157 * When flushing dentries from proc, one needs to flush them from global
60347f67 3158 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 3159 * in. This call is supposed to do all of this job.
3160 *
3161 * Looks in the dcache for
3162 * /proc/@pid
3163 * /proc/@tgid/task/@pid
3164 * if either directory is present flushes it and all of it'ts children
3165 * from the dcache.
3166 *
3167 * It is safe and reasonable to cache /proc entries for a task until
3168 * that task exits. After that they just clog up the dcache with
3169 * useless entries, possibly causing useful dcache entries to be
3170 * flushed instead. This routine is proved to flush those useless
3171 * dcache entries at process exit time.
3172 *
3173 * NOTE: This routine is just an optimization so it does not guarantee
3174 * that no dcache entries will exist at process exit time it
3175 * just makes it very unlikely that any will persist.
60347f67
PE		 3176 */
3177
3178void proc_flush_task(struct task_struct *task)
3179{
9fcc2d15 3180 int i;
9b4d1cbe 3181 struct pid *pid, *tgid;
130f77ec
PE		 3182 struct upid *upid;
3183
130f77ec 3184 pid = task_pid(task);
9b4d1cbe 3185 tgid = task_tgid(task);
130f77ec 3186
9fcc2d15 3187 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 3188 upid = &pid->numbers[i];
3189 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 3190 tgid->numbers[i].nr);
130f77ec 3191 }
6f4e6433
PE		 3192
3193 upid = &pid->numbers[pid->level];
3194 if (upid->nr == 1)
3195 pid_ns_release_proc(upid->ns);
60347f67
PE		 3196}
3197
9711ef99
AB		 3198static struct dentry *proc_pid_instantiate(struct inode *dir,
3199 struct dentry * dentry,
c5141e6d 3200 struct task_struct *task, const void *ptr)
444ceed8
EB		 3201{
3202 struct dentry *error = ERR_PTR(-ENOENT);
3203 struct inode *inode;
3204
61a28784 3205 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3206 if (!inode)
3207 goto out;
3208
3209 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3210 inode->i_op = &proc_tgid_base_inode_operations;
3211 inode->i_fop = &proc_tgid_base_operations;
3212 inode->i_flags|=S_IMMUTABLE;
aed54175 3213
bfe86848
MS		 3214 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff,
3215 ARRAY_SIZE(tgid_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
1da177e4
LT		 3227struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3228{
73d36460 3229 struct dentry *result;
1da177e4 3230 struct task_struct *task;
1da177e4 3231 unsigned tgid;
b488893a 3232 struct pid_namespace *ns;
1da177e4 3233
801199ce
EB		 3234 result = proc_base_lookup(dir, dentry);
3235 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
3236 goto out;
3237
1da177e4
LT		 3238 tgid = name_to_int(dentry);
3239 if (tgid == ~0U)
3240 goto out;
3241
b488893a 3242 ns = dentry->d_sb->s_fs_info;
de758734 3243 rcu_read_lock();
b488893a 3244 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 3245 if (task)
3246 get_task_struct(task);
de758734 3247 rcu_read_unlock();
1da177e4
LT		 3248 if (!task)
3249 goto out;
3250
444ceed8 3251 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 3252 put_task_struct(task);
1da177e4 3253out:
cd6a3ce9 3254 return result;
1da177e4
LT		 3255}
3256
1da177e4 3257/*
0804ef4b 3258 * Find the first task with tgid >= tgid
0bc58a91 3259 *
1da177e4 3260 */
19fd4bb2
EB		 3261struct tgid_iter {
3262 unsigned int tgid;
0804ef4b 3263 struct task_struct *task;
19fd4bb2
EB		 3264};
3265static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3266{
0804ef4b 3267 struct pid *pid;
1da177e4 3268
19fd4bb2
EB		 3269 if (iter.task)
3270 put_task_struct(iter.task);
454cc105 3271 rcu_read_lock();
0804ef4b 3272retry:
19fd4bb2
EB		 3273 iter.task = NULL;
3274 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 3275 if (pid) {
19fd4bb2
EB		 3276 iter.tgid = pid_nr_ns(pid, ns);
3277 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 3278 /* What we to know is if the pid we have find is the
3279 * pid of a thread_group_leader. Testing for task
3280 * being a thread_group_leader is the obvious thing
3281 * todo but there is a window when it fails, due to
3282 * the pid transfer logic in de_thread.
3283 *
3284 * So we perform the straight forward test of seeing
3285 * if the pid we have found is the pid of a thread
3286 * group leader, and don't worry if the task we have
3287 * found doesn't happen to be a thread group leader.
3288 * As we don't care in the case of readdir.
3289 */
19fd4bb2
EB		 3290 if (!iter.task || !has_group_leader_pid(iter.task)) {
3291 iter.tgid += 1;
0804ef4b 3292 goto retry;
19fd4bb2
EB		 3293 }
3294 get_task_struct(iter.task);
0bc58a91 3295 }
454cc105 3296 rcu_read_unlock();
19fd4bb2 3297 return iter;
1da177e4
LT		 3298}
3299
7bcd6b0e 3300#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
0804ef4b 3301
61a28784 3302static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
19fd4bb2 3303 struct tgid_iter iter)
61a28784
EB		 3304{
3305 char name[PROC_NUMBUF];
19fd4bb2 3306 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
61a28784 3307 return proc_fill_cache(filp, dirent, filldir, name, len,
19fd4bb2 3308 proc_pid_instantiate, iter.task, NULL);
61a28784
EB		 3309}
3310
0499680a
VK		 3311static int fake_filldir(void *buf, const char *name, int namelen,
3312 loff_t offset, u64 ino, unsigned d_type)
3313{
3314 return 0;
3315}
3316
1da177e4
LT		 3317/* for the /proc/ directory itself, after non-process stuff has been done */
3318int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3319{
d8bdc59f
LT		 3320 unsigned int nr;
3321 struct task_struct *reaper;
19fd4bb2 3322 struct tgid_iter iter;
b488893a 3323 struct pid_namespace *ns;
0499680a 3324 filldir_t __filldir;
1da177e4 3325
d8bdc59f
LT		 3326 if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
3327 goto out_no_task;
3328 nr = filp->f_pos - FIRST_PROCESS_ENTRY;
3329
3330 reaper = get_proc_task(filp->f_path.dentry->d_inode);
61a28784
EB		 3331 if (!reaper)
3332 goto out_no_task;
3333
7bcd6b0e 3334 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
c5141e6d 3335 const struct pid_entry *p = &proc_base_stuff[nr];
61a28784 3336 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
801199ce 3337 goto out;
1da177e4
LT		 3338 }
3339
b488893a 3340 ns = filp->f_dentry->d_sb->s_fs_info;
19fd4bb2
EB		 3341 iter.task = NULL;
3342 iter.tgid = filp->f_pos - TGID_OFFSET;
3343 for (iter = next_tgid(ns, iter);
3344 iter.task;
3345 iter.tgid += 1, iter = next_tgid(ns, iter)) {
0499680a
VK		 3346 if (has_pid_permissions(ns, iter.task, 2))
3347 __filldir = filldir;
3348 else
3349 __filldir = fake_filldir;
3350
19fd4bb2 3351 filp->f_pos = iter.tgid + TGID_OFFSET;
0499680a 3352 if (proc_pid_fill_cache(filp, dirent, __filldir, iter) < 0) {
19fd4bb2 3353 put_task_struct(iter.task);
0804ef4b 3354 goto out;
1da177e4 3355 }
0bc58a91 3356 }
0804ef4b
EB		 3357 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3358out:
61a28784
EB		 3359 put_task_struct(reaper);
3360out_no_task:
0bc58a91
EB		 3361 return 0;
3362}
1da177e4 3363
28a6d671
EB		 3364/*
3365 * Tasks
3366 */
c5141e6d 3367static const struct pid_entry tid_base_stuff[] = {
631f9c18 3368 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3369 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 3370 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
631f9c18
AD		 3371 REG("environ", S_IRUSR, proc_environ_operations),
3372 INF("auxv", S_IRUSR, proc_pid_auxv),
3373 ONE("status", S_IRUGO, proc_pid_status),
a9712bc1 3374 ONE("personality", S_IRUGO, proc_pid_personality),
3036e7b4 3375 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3376#ifdef CONFIG_SCHED_DEBUG
631f9c18 3377 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3378#endif
4614a696 3379 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3380#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
a9712bc1 3381 INF("syscall", S_IRUGO, proc_pid_syscall),
43ae34cb 3382#endif
631f9c18
AD		 3383 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3384 ONE("stat", S_IRUGO, proc_tid_stat),
3385 ONE("statm", S_IRUGO, proc_pid_statm),
3386 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3387#ifdef CONFIG_NUMA
631f9c18 3388 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3389#endif
631f9c18
AD		 3390 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3391 LNK("cwd", proc_cwd_link),
3392 LNK("root", proc_root_link),
3393 LNK("exe", proc_exe_link),
3394 REG("mounts", S_IRUGO, proc_mounts_operations),
3395 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3396#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3397 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3398 REG("smaps", S_IRUGO, proc_smaps_operations),
ca6b0bf0 3399 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 3400#endif
3401#ifdef CONFIG_SECURITY
631f9c18 3402 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3403#endif
3404#ifdef CONFIG_KALLSYMS
631f9c18 3405 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3406#endif
2ec220e2 3407#ifdef CONFIG_STACKTRACE
a9712bc1 3408 ONE("stack", S_IRUGO, proc_pid_stack),
28a6d671
EB		 3409#endif
3410#ifdef CONFIG_SCHEDSTATS
631f9c18 3411 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3412#endif
9745512c 3413#ifdef CONFIG_LATENCYTOP
631f9c18 3414 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3415#endif
8793d854 3416#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3417 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3418#endif
3419#ifdef CONFIG_CGROUPS
631f9c18 3420 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3421#endif
631f9c18
AD		 3422 INF("oom_score", S_IRUGO, proc_oom_score),
3423 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3424 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3425#ifdef CONFIG_AUDITSYSCALL
631f9c18 3426 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
26ec3c64 3427 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3428#endif
f4f154fd 3429#ifdef CONFIG_FAULT_INJECTION
631f9c18 3430 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3431#endif
297c5d92 3432#ifdef CONFIG_TASK_IO_ACCOUNTING
1d1221f3 3433 INF("io", S_IRUSR, proc_tid_io_accounting),
297c5d92 3434#endif
f133ecca
CM		 3435#ifdef CONFIG_HARDWALL
3436 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3437#endif
28a6d671
EB		 3438};
3439
3440static int proc_tid_base_readdir(struct file * filp,
3441 void * dirent, filldir_t filldir)
3442{
3443 return proc_pident_readdir(filp,dirent,filldir,
3444 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3445}
3446
3447static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3448 return proc_pident_lookup(dir, dentry,
3449 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3450}
3451
00977a59 3452static const struct file_operations proc_tid_base_operations = {
28a6d671
EB		 3453 .read = generic_read_dir,
3454 .readdir = proc_tid_base_readdir,
6038f373 3455 .llseek = default_llseek,
28a6d671
EB		 3456};
3457
c5ef1c42 3458static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3459 .lookup = proc_tid_base_lookup,
3460 .getattr = pid_getattr,
3461 .setattr = proc_setattr,
3462};
3463
444ceed8 3464static struct dentry *proc_task_instantiate(struct inode *dir,
c5141e6d 3465 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8
EB		 3466{
3467 struct dentry *error = ERR_PTR(-ENOENT);
3468 struct inode *inode;
61a28784 3469 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3470
3471 if (!inode)
3472 goto out;
3473 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3474 inode->i_op = &proc_tid_base_inode_operations;
3475 inode->i_fop = &proc_tid_base_operations;
3476 inode->i_flags|=S_IMMUTABLE;
aed54175 3477
bfe86848
MS		 3478 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff,
3479 ARRAY_SIZE(tid_base_stuff)));
444ceed8 3480
fb045adb 3481 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3482
3483 d_add(dentry, inode);
3484 /* Close the race of the process dying before we return the dentry */
3485 if (pid_revalidate(dentry, NULL))
3486 error = NULL;
3487out:
3488 return error;
3489}
3490
28a6d671
EB		 3491static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3492{
3493 struct dentry *result = ERR_PTR(-ENOENT);
3494 struct task_struct *task;
3495 struct task_struct *leader = get_proc_task(dir);
28a6d671 3496 unsigned tid;
b488893a 3497 struct pid_namespace *ns;
28a6d671
EB		 3498
3499 if (!leader)
3500 goto out_no_task;
3501
3502 tid = name_to_int(dentry);
3503 if (tid == ~0U)
3504 goto out;
3505
b488893a 3506 ns = dentry->d_sb->s_fs_info;
28a6d671 3507 rcu_read_lock();
b488893a 3508 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3509 if (task)
3510 get_task_struct(task);
3511 rcu_read_unlock();
3512 if (!task)
3513 goto out;
bac0abd6 3514 if (!same_thread_group(leader, task))
28a6d671
EB		 3515 goto out_drop_task;
3516
444ceed8 3517 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3518out_drop_task:
3519 put_task_struct(task);
3520out:
3521 put_task_struct(leader);
3522out_no_task:
3523 return result;
3524}
3525
0bc58a91
EB		 3526/*
3527 * Find the first tid of a thread group to return to user space.
3528 *
3529 * Usually this is just the thread group leader, but if the users
3530 * buffer was too small or there was a seek into the middle of the
3531 * directory we have more work todo.
3532 *
3533 * In the case of a short read we start with find_task_by_pid.
3534 *
3535 * In the case of a seek we start with the leader and walk nr
3536 * threads past it.
3537 */
cc288738 3538static struct task_struct *first_tid(struct task_struct *leader,
b488893a 3539 int tid, int nr, struct pid_namespace *ns)
0bc58a91 3540{
a872ff0c 3541 struct task_struct *pos;
1da177e4 3542
cc288738 3543 rcu_read_lock();
0bc58a91
EB		 3544 /* Attempt to start with the pid of a thread */
3545 if (tid && (nr > 0)) {
b488893a 3546 pos = find_task_by_pid_ns(tid, ns);
a872ff0c
ON		 3547 if (pos && (pos->group_leader == leader))
3548 goto found;
0bc58a91 3549 }
1da177e4 3550
0bc58a91 3551 /* If nr exceeds the number of threads there is nothing todo */
a872ff0c
ON		 3552 pos = NULL;
3553 if (nr && nr >= get_nr_threads(leader))
3554 goto out;
1da177e4 3555
a872ff0c
ON		 3556 /* If we haven't found our starting place yet start
3557 * with the leader and walk nr threads forward.
0bc58a91 3558 */
a872ff0c
ON		 3559 for (pos = leader; nr > 0; --nr) {
3560 pos = next_thread(pos);
3561 if (pos == leader) {
3562 pos = NULL;
3563 goto out;
3564 }
1da177e4 3565 }
a872ff0c
ON		 3566found:
3567 get_task_struct(pos);
3568out:
cc288738 3569 rcu_read_unlock();
0bc58a91
EB		 3570 return pos;
3571}
3572
3573/*
3574 * Find the next thread in the thread list.
3575 * Return NULL if there is an error or no next thread.
3576 *
3577 * The reference to the input task_struct is released.
3578 */
3579static struct task_struct *next_tid(struct task_struct *start)
3580{
c1df7fb8 3581 struct task_struct *pos = NULL;
cc288738 3582 rcu_read_lock();
c1df7fb8 3583 if (pid_alive(start)) {
0bc58a91 3584 pos = next_thread(start);
c1df7fb8
ON		 3585 if (thread_group_leader(pos))
3586 pos = NULL;
3587 else
3588 get_task_struct(pos);
3589 }
cc288738 3590 rcu_read_unlock();
0bc58a91
EB		 3591 put_task_struct(start);
3592 return pos;
1da177e4
LT		 3593}
3594
61a28784
EB		 3595static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3596 struct task_struct *task, int tid)
3597{
3598 char name[PROC_NUMBUF];
3599 int len = snprintf(name, sizeof(name), "%d", tid);
3600 return proc_fill_cache(filp, dirent, filldir, name, len,
3601 proc_task_instantiate, task, NULL);
3602}
3603
1da177e4
LT		 3604/* for the /proc/TGID/task/ directories */
3605static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3606{
2fddfeef 3607 struct dentry *dentry = filp->f_path.dentry;
1da177e4 3608 struct inode *inode = dentry->d_inode;
7d895244 3609 struct task_struct *leader = NULL;
0bc58a91 3610 struct task_struct *task;
1da177e4
LT		 3611 int retval = -ENOENT;
3612 ino_t ino;
0bc58a91 3613 int tid;
b488893a 3614 struct pid_namespace *ns;
1da177e4 3615
7d895244
GC		 3616 task = get_proc_task(inode);
3617 if (!task)
3618 goto out_no_task;
3619 rcu_read_lock();
3620 if (pid_alive(task)) {
3621 leader = task->group_leader;
3622 get_task_struct(leader);
3623 }
3624 rcu_read_unlock();
3625 put_task_struct(task);
99f89551
EB		 3626 if (!leader)
3627 goto out_no_task;
1da177e4
LT		 3628 retval = 0;
3629
ee568b25 3630 switch ((unsigned long)filp->f_pos) {
1da177e4
LT		 3631 case 0:
3632 ino = inode->i_ino;
ee6f779b 3633 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3634 goto out;
ee6f779b 3635 filp->f_pos++;
1da177e4
LT		 3636 /* fall through */
3637 case 1:
3638 ino = parent_ino(dentry);
ee6f779b 3639 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3640 goto out;
ee6f779b 3641 filp->f_pos++;
1da177e4
LT		 3642 /* fall through */
3643 }
3644
0bc58a91
EB		 3645 /* f_version caches the tgid value that the last readdir call couldn't
3646 * return. lseek aka telldir automagically resets f_version to 0.
3647 */
b488893a 3648 ns = filp->f_dentry->d_sb->s_fs_info;
2b47c361 3649 tid = (int)filp->f_version;
0bc58a91 3650 filp->f_version = 0;
ee6f779b 3651 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
0bc58a91 3652 task;
ee6f779b 3653 task = next_tid(task), filp->f_pos++) {
b488893a 3654 tid = task_pid_nr_ns(task, ns);
61a28784 3655 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
0bc58a91
EB		 3656 /* returning this tgid failed, save it as the first
3657 * pid for the next readir call */
2b47c361 3658 filp->f_version = (u64)tid;
0bc58a91 3659 put_task_struct(task);
1da177e4 3660 break;
0bc58a91 3661 }
1da177e4
LT		 3662 }
3663out:
99f89551
EB		 3664 put_task_struct(leader);
3665out_no_task:
1da177e4
LT		 3666 return retval;
3667}
6e66b52b
EB		 3668
3669static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3670{
3671 struct inode *inode = dentry->d_inode;
99f89551 3672 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3673 generic_fillattr(inode, stat);
3674
99f89551 3675 if (p) {
99f89551 3676 stat->nlink += get_nr_threads(p);
99f89551 3677 put_task_struct(p);
6e66b52b
EB		 3678 }
3679
3680 return 0;
3681}
28a6d671 3682
c5ef1c42 3683static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3684 .lookup = proc_task_lookup,
3685 .getattr = proc_task_getattr,
3686 .setattr = proc_setattr,
0499680a 3687 .permission = proc_pid_permission,
28a6d671
EB		 3688};
3689
00977a59 3690static const struct file_operations proc_task_operations = {
28a6d671
EB		 3691 .read = generic_read_dir,
3692 .readdir = proc_task_readdir,
6038f373 3693 .llseek = default_llseek,
28a6d671 3694};
Linux 6.x block layer and io_uring tree(s)