projects / deliverable / linux.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
proc: unify mem_read() and mem_write()
[deliverable/linux.git] / fs / proc / base.c
CommitLineData
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
572d34b9
ON		 721static ssize_t mem_rw(struct file *file, char __user *buf,
722 size_t count, loff_t *ppos, int write)
1da177e4 723{
e268337d 724 struct mm_struct *mm = file->private_data;
572d34b9
ON		 725 unsigned long addr = *ppos;
726 ssize_t copied;
1da177e4 727 char *page;
1da177e4 728
e268337d
LT		 729 if (!mm)
730 return 0;
99f89551 731
30cd8903
KM		 732 page = (char *)__get_free_page(GFP_TEMPORARY);
733 if (!page)
e268337d 734 return -ENOMEM;
1da177e4 735
f7ca54f4 736 copied = 0;
1da177e4 737 while (count > 0) {
572d34b9 738 int this_len = min_t(int, count, PAGE_SIZE);
1da177e4 739
572d34b9 740 if (write && copy_from_user(page, buf, this_len)) {
1da177e4
LT		 741 copied = -EFAULT;
742 break;
743 }
572d34b9
ON		 744
745 this_len = access_remote_vm(mm, addr, page, this_len, write);
746 if (!this_len) {
1da177e4
LT		 747 if (!copied)
748 copied = -EIO;
749 break;
750 }
572d34b9
ON		 751
752 if (!write && copy_to_user(buf, page, this_len)) {
753 copied = -EFAULT;
754 break;
755 }
756
757 buf += this_len;
758 addr += this_len;
759 copied += this_len;
760 count -= this_len;
1da177e4 761 }
572d34b9 762 *ppos = addr;
30cd8903 763
30cd8903 764 free_page((unsigned long) page);
1da177e4
LT		 765 return copied;
766}
1da177e4 767
572d34b9
ON		 768static ssize_t mem_read(struct file *file, char __user *buf,
769 size_t count, loff_t *ppos)
770{
771 return mem_rw(file, buf, count, ppos, 0);
772}
773
774static ssize_t mem_write(struct file *file, const char __user *buf,
775 size_t count, loff_t *ppos)
776{
777 return mem_rw(file, (char __user*)buf, count, ppos, 1);
778}
779
85863e47 780loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 781{
782 switch (orig) {
783 case 0:
784 file->f_pos = offset;
785 break;
786 case 1:
787 file->f_pos += offset;
788 break;
789 default:
790 return -EINVAL;
791 }
792 force_successful_syscall_return();
793 return file->f_pos;
794}
795
e268337d
LT		 796static int mem_release(struct inode *inode, struct file *file)
797{
798 struct mm_struct *mm = file->private_data;
71879d3c
ON		 799 if (mm)
800 mmput(mm);
e268337d
LT		 801 return 0;
802}
803
00977a59 804static const struct file_operations proc_mem_operations = {
1da177e4
LT		 805 .llseek = mem_lseek,
806 .read = mem_read,
807 .write = mem_write,
808 .open = mem_open,
e268337d 809 .release = mem_release,
1da177e4
LT		 810};
811
315e28c8
JP		 812static ssize_t environ_read(struct file *file, char __user *buf,
813 size_t count, loff_t *ppos)
814{
815 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
816 char *page;
817 unsigned long src = *ppos;
818 int ret = -ESRCH;
819 struct mm_struct *mm;
820
821 if (!task)
822 goto out_no_task;
823
315e28c8
JP		 824 ret = -ENOMEM;
825 page = (char *)__get_free_page(GFP_TEMPORARY);
826 if (!page)
827 goto out;
828
315e28c8 829
d6f64b89
AV		 830 mm = mm_for_maps(task);
831 ret = PTR_ERR(mm);
832 if (!mm || IS_ERR(mm))
315e28c8
JP		 833 goto out_free;
834
d6f64b89 835 ret = 0;
315e28c8
JP		 836 while (count > 0) {
837 int this_len, retval, max_len;
838
839 this_len = mm->env_end - (mm->env_start + src);
840
841 if (this_len <= 0)
842 break;
843
844 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
845 this_len = (this_len > max_len) ? max_len : this_len;
846
847 retval = access_process_vm(task, (mm->env_start + src),
848 page, this_len, 0);
849
850 if (retval <= 0) {
851 ret = retval;
852 break;
853 }
854
855 if (copy_to_user(buf, page, retval)) {
856 ret = -EFAULT;
857 break;
858 }
859
860 ret += retval;
861 src += retval;
862 buf += retval;
863 count -= retval;
864 }
865 *ppos = src;
866
867 mmput(mm);
868out_free:
869 free_page((unsigned long) page);
870out:
871 put_task_struct(task);
872out_no_task:
873 return ret;
874}
875
876static const struct file_operations proc_environ_operations = {
877 .read = environ_read,
87df8424 878 .llseek = generic_file_llseek,
315e28c8
JP		 879};
880
1da177e4
LT		 881static ssize_t oom_adjust_read(struct file *file, char __user *buf,
882 size_t count, loff_t *ppos)
883{
2fddfeef 884 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
8578cea7 885 char buffer[PROC_NUMBUF];
1da177e4 886 size_t len;
28b83c51
KM		 887 int oom_adjust = OOM_DISABLE;
888 unsigned long flags;
1da177e4 889
99f89551
EB		 890 if (!task)
891 return -ESRCH;
28b83c51
KM		 892
893 if (lock_task_sighand(task, &flags)) {
894 oom_adjust = task->signal->oom_adj;
895 unlock_task_sighand(task, &flags);
896 }
897
99f89551
EB		 898 put_task_struct(task);
899
8578cea7 900 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
0c28f287
AM		 901
902 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1da177e4
LT		 903}
904
905static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
906 size_t count, loff_t *ppos)
907{
99f89551 908 struct task_struct *task;
5d863b89 909 char buffer[PROC_NUMBUF];
0a8cb8e3 910 int oom_adjust;
28b83c51 911 unsigned long flags;
5d863b89 912 int err;
1da177e4 913
8578cea7
EB		 914 memset(buffer, 0, sizeof(buffer));
915 if (count > sizeof(buffer) - 1)
916 count = sizeof(buffer) - 1;
723548bf
DR		 917 if (copy_from_user(buffer, buf, count)) {
918 err = -EFAULT;
919 goto out;
920 }
5d863b89 921
0a8cb8e3 922 err = kstrtoint(strstrip(buffer), 0, &oom_adjust);
5d863b89 923 if (err)
723548bf 924 goto out;
8ac773b4 925 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
723548bf
DR		 926 oom_adjust != OOM_DISABLE) {
927 err = -EINVAL;
928 goto out;
929 }
5d863b89 930
2fddfeef 931 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 932 if (!task) {
933 err = -ESRCH;
934 goto out;
935 }
d19d5476
DR		 936
937 task_lock(task);
938 if (!task->mm) {
939 err = -EINVAL;
940 goto err_task_lock;
941 }
942
28b83c51 943 if (!lock_task_sighand(task, &flags)) {
723548bf 944 err = -ESRCH;
d19d5476 945 goto err_task_lock;
28b83c51
KM		 946 }
947
948 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 949 err = -EACCES;
950 goto err_sighand;
8fb4fc68 951 }
28b83c51 952
51b1bd2a
DR		 953 /*
954 * Warn that /proc/pid/oom_adj is deprecated, see
955 * Documentation/feature-removal-schedule.txt.
956 */
c2142704 957 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
be8f684d
DR		 958 current->comm, task_pid_nr(current), task_pid_nr(task),
959 task_pid_nr(task));
28b83c51 960 task->signal->oom_adj = oom_adjust;
a63d83f4
DR		 961 /*
962 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
963 * value is always attainable.
964 */
965 if (task->signal->oom_adj == OOM_ADJUST_MAX)
966 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
967 else
968 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
969 -OOM_DISABLE;
43d2b113 970 trace_oom_score_adj_update(task);
723548bf 971err_sighand:
28b83c51 972 unlock_task_sighand(task, &flags);
d19d5476
DR		 973err_task_lock:
974 task_unlock(task);
99f89551 975 put_task_struct(task);
723548bf
DR		 976out:
977 return err < 0 ? err : count;
1da177e4
LT		 978}
979
00977a59 980static const struct file_operations proc_oom_adjust_operations = {
1da177e4
LT		 981 .read = oom_adjust_read,
982 .write = oom_adjust_write,
87df8424 983 .llseek = generic_file_llseek,
1da177e4
LT		 984};
985
a63d83f4
DR		 986static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
987 size_t count, loff_t *ppos)
988{
989 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
990 char buffer[PROC_NUMBUF];
991 int oom_score_adj = OOM_SCORE_ADJ_MIN;
992 unsigned long flags;
993 size_t len;
994
995 if (!task)
996 return -ESRCH;
997 if (lock_task_sighand(task, &flags)) {
998 oom_score_adj = task->signal->oom_score_adj;
999 unlock_task_sighand(task, &flags);
1000 }
1001 put_task_struct(task);
1002 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
1003 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1004}
1005
1006static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1007 size_t count, loff_t *ppos)
1008{
1009 struct task_struct *task;
1010 char buffer[PROC_NUMBUF];
1011 unsigned long flags;
0a8cb8e3 1012 int oom_score_adj;
a63d83f4
DR		 1013 int err;
1014
1015 memset(buffer, 0, sizeof(buffer));
1016 if (count > sizeof(buffer) - 1)
1017 count = sizeof(buffer) - 1;
723548bf
DR		 1018 if (copy_from_user(buffer, buf, count)) {
1019 err = -EFAULT;
1020 goto out;
1021 }
a63d83f4 1022
0a8cb8e3 1023 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
a63d83f4 1024 if (err)
723548bf 1025 goto out;
a63d83f4 1026 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
723548bf
DR		 1027 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1028 err = -EINVAL;
1029 goto out;
1030 }
a63d83f4
DR		 1031
1032 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 1033 if (!task) {
1034 err = -ESRCH;
1035 goto out;
1036 }
d19d5476
DR		 1037
1038 task_lock(task);
1039 if (!task->mm) {
1040 err = -EINVAL;
1041 goto err_task_lock;
1042 }
1043
a63d83f4 1044 if (!lock_task_sighand(task, &flags)) {
723548bf 1045 err = -ESRCH;
d19d5476 1046 goto err_task_lock;
a63d83f4 1047 }
d19d5476 1048
dabb16f6 1049 if (oom_score_adj < task->signal->oom_score_adj_min &&
a63d83f4 1050 !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 1051 err = -EACCES;
1052 goto err_sighand;
a63d83f4
DR		 1053 }
1054
1055 task->signal->oom_score_adj = oom_score_adj;
dabb16f6
MSB		 1056 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1057 task->signal->oom_score_adj_min = oom_score_adj;
43d2b113 1058 trace_oom_score_adj_update(task);
a63d83f4
DR		 1059 /*
1060 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1061 * always attainable.
1062 */
1063 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1064 task->signal->oom_adj = OOM_DISABLE;
1065 else
1066 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1067 OOM_SCORE_ADJ_MAX;
723548bf 1068err_sighand:
a63d83f4 1069 unlock_task_sighand(task, &flags);
d19d5476
DR		 1070err_task_lock:
1071 task_unlock(task);
a63d83f4 1072 put_task_struct(task);
723548bf
DR		 1073out:
1074 return err < 0 ? err : count;
a63d83f4
DR		 1075}
1076
1077static const struct file_operations proc_oom_score_adj_operations = {
1078 .read = oom_score_adj_read,
1079 .write = oom_score_adj_write,
6038f373 1080 .llseek = default_llseek,
a63d83f4
DR		 1081};
1082
1da177e4
LT		 1083#ifdef CONFIG_AUDITSYSCALL
1084#define TMPBUFLEN 21
1085static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1086 size_t count, loff_t *ppos)
1087{
2fddfeef 1088 struct inode * inode = file->f_path.dentry->d_inode;
99f89551 1089 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1090 ssize_t length;
1091 char tmpbuf[TMPBUFLEN];
1092
99f89551
EB		 1093 if (!task)
1094 return -ESRCH;
1da177e4 1095 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
0c11b942 1096 audit_get_loginuid(task));
99f89551 1097 put_task_struct(task);
1da177e4
LT		 1098 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1099}
1100
1101static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1102 size_t count, loff_t *ppos)
1103{
2fddfeef 1104 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1105 char *page, *tmp;
1106 ssize_t length;
1da177e4
LT		 1107 uid_t loginuid;
1108
7dc52157
PM		 1109 rcu_read_lock();
1110 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1111 rcu_read_unlock();
1da177e4 1112 return -EPERM;
7dc52157
PM		 1113 }
1114 rcu_read_unlock();
1da177e4 1115
e0182909
AV		 1116 if (count >= PAGE_SIZE)
1117 count = PAGE_SIZE - 1;
1da177e4
LT		 1118
1119 if (*ppos != 0) {
1120 /* No partial writes. */
1121 return -EINVAL;
1122 }
e12ba74d 1123 page = (char*)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 1124 if (!page)
1125 return -ENOMEM;
1126 length = -EFAULT;
1127 if (copy_from_user(page, buf, count))
1128 goto out_free_page;
1129
e0182909 1130 page[count] = '\0';
1da177e4
LT		 1131 loginuid = simple_strtoul(page, &tmp, 10);
1132 if (tmp == page) {
1133 length = -EINVAL;
1134 goto out_free_page;
1135
1136 }
0a300be6 1137 length = audit_set_loginuid(loginuid);
1da177e4
LT		 1138 if (likely(length == 0))
1139 length = count;
1140
1141out_free_page:
1142 free_page((unsigned long) page);
1143 return length;
1144}
1145
00977a59 1146static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1147 .read = proc_loginuid_read,
1148 .write = proc_loginuid_write,
87df8424 1149 .llseek = generic_file_llseek,
1da177e4 1150};
1e0bd755
EP		 1151
1152static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1153 size_t count, loff_t *ppos)
1154{
1155 struct inode * inode = file->f_path.dentry->d_inode;
1156 struct task_struct *task = get_proc_task(inode);
1157 ssize_t length;
1158 char tmpbuf[TMPBUFLEN];
1159
1160 if (!task)
1161 return -ESRCH;
1162 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1163 audit_get_sessionid(task));
1164 put_task_struct(task);
1165 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1166}
1167
1168static const struct file_operations proc_sessionid_operations = {
1169 .read = proc_sessionid_read,
87df8424 1170 .llseek = generic_file_llseek,
1e0bd755 1171};
1da177e4
LT		 1172#endif
1173
f4f154fd
AM		 1174#ifdef CONFIG_FAULT_INJECTION
1175static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1176 size_t count, loff_t *ppos)
1177{
1178 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1179 char buffer[PROC_NUMBUF];
1180 size_t len;
1181 int make_it_fail;
f4f154fd
AM		 1182
1183 if (!task)
1184 return -ESRCH;
1185 make_it_fail = task->make_it_fail;
1186 put_task_struct(task);
1187
1188 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1189
1190 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1191}
1192
1193static ssize_t proc_fault_inject_write(struct file * file,
1194 const char __user * buf, size_t count, loff_t *ppos)
1195{
1196 struct task_struct *task;
1197 char buffer[PROC_NUMBUF], *end;
1198 int make_it_fail;
1199
1200 if (!capable(CAP_SYS_RESOURCE))
1201 return -EPERM;
1202 memset(buffer, 0, sizeof(buffer));
1203 if (count > sizeof(buffer) - 1)
1204 count = sizeof(buffer) - 1;
1205 if (copy_from_user(buffer, buf, count))
1206 return -EFAULT;
cba8aafe
VL		 1207 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1208 if (*end)
1209 return -EINVAL;
f4f154fd
AM		 1210 task = get_proc_task(file->f_dentry->d_inode);
1211 if (!task)
1212 return -ESRCH;
1213 task->make_it_fail = make_it_fail;
1214 put_task_struct(task);
cba8aafe
VL		 1215
1216 return count;
f4f154fd
AM		 1217}
1218
00977a59 1219static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1220 .read = proc_fault_inject_read,
1221 .write = proc_fault_inject_write,
87df8424 1222 .llseek = generic_file_llseek,
f4f154fd
AM		 1223};
1224#endif
1225
9745512c 1226
43ae34cb
IM		 1227#ifdef CONFIG_SCHED_DEBUG
1228/*
1229 * Print out various scheduling related per-task fields:
1230 */
1231static int sched_show(struct seq_file *m, void *v)
1232{
1233 struct inode *inode = m->private;
1234 struct task_struct *p;
1235
43ae34cb
IM		 1236 p = get_proc_task(inode);
1237 if (!p)
1238 return -ESRCH;
1239 proc_sched_show_task(p, m);
1240
1241 put_task_struct(p);
1242
1243 return 0;
1244}
1245
1246static ssize_t
1247sched_write(struct file *file, const char __user *buf,
1248 size_t count, loff_t *offset)
1249{
1250 struct inode *inode = file->f_path.dentry->d_inode;
1251 struct task_struct *p;
1252
43ae34cb
IM		 1253 p = get_proc_task(inode);
1254 if (!p)
1255 return -ESRCH;
1256 proc_sched_set_task(p);
1257
1258 put_task_struct(p);
1259
1260 return count;
1261}
1262
1263static int sched_open(struct inode *inode, struct file *filp)
1264{
c6a34058 1265 return single_open(filp, sched_show, inode);
43ae34cb
IM		 1266}
1267
1268static const struct file_operations proc_pid_sched_operations = {
1269 .open = sched_open,
1270 .read = seq_read,
1271 .write = sched_write,
1272 .llseek = seq_lseek,
5ea473a1 1273 .release = single_release,
43ae34cb
IM		 1274};
1275
1276#endif
1277
5091faa4
MG		 1278#ifdef CONFIG_SCHED_AUTOGROUP
1279/*
1280 * Print out autogroup related information:
1281 */
1282static int sched_autogroup_show(struct seq_file *m, void *v)
1283{
1284 struct inode *inode = m->private;
1285 struct task_struct *p;
1286
1287 p = get_proc_task(inode);
1288 if (!p)
1289 return -ESRCH;
1290 proc_sched_autogroup_show_task(p, m);
1291
1292 put_task_struct(p);
1293
1294 return 0;
1295}
1296
1297static ssize_t
1298sched_autogroup_write(struct file *file, const char __user *buf,
1299 size_t count, loff_t *offset)
1300{
1301 struct inode *inode = file->f_path.dentry->d_inode;
1302 struct task_struct *p;
1303 char buffer[PROC_NUMBUF];
0a8cb8e3 1304 int nice;
5091faa4
MG		 1305 int err;
1306
1307 memset(buffer, 0, sizeof(buffer));
1308 if (count > sizeof(buffer) - 1)
1309 count = sizeof(buffer) - 1;
1310 if (copy_from_user(buffer, buf, count))
1311 return -EFAULT;
1312
0a8cb8e3
AD		 1313 err = kstrtoint(strstrip(buffer), 0, &nice);
1314 if (err < 0)
1315 return err;
5091faa4
MG		 1316
1317 p = get_proc_task(inode);
1318 if (!p)
1319 return -ESRCH;
1320
1321 err = nice;
1322 err = proc_sched_autogroup_set_nice(p, &err);
1323 if (err)
1324 count = err;
1325
1326 put_task_struct(p);
1327
1328 return count;
1329}
1330
1331static int sched_autogroup_open(struct inode *inode, struct file *filp)
1332{
1333 int ret;
1334
1335 ret = single_open(filp, sched_autogroup_show, NULL);
1336 if (!ret) {
1337 struct seq_file *m = filp->private_data;
1338
1339 m->private = inode;
1340 }
1341 return ret;
1342}
1343
1344static const struct file_operations proc_pid_sched_autogroup_operations = {
1345 .open = sched_autogroup_open,
1346 .read = seq_read,
1347 .write = sched_autogroup_write,
1348 .llseek = seq_lseek,
1349 .release = single_release,
1350};
1351
1352#endif /* CONFIG_SCHED_AUTOGROUP */
1353
4614a696 1354static ssize_t comm_write(struct file *file, const char __user *buf,
1355 size_t count, loff_t *offset)
1356{
1357 struct inode *inode = file->f_path.dentry->d_inode;
1358 struct task_struct *p;
1359 char buffer[TASK_COMM_LEN];
1360
1361 memset(buffer, 0, sizeof(buffer));
1362 if (count > sizeof(buffer) - 1)
1363 count = sizeof(buffer) - 1;
1364 if (copy_from_user(buffer, buf, count))
1365 return -EFAULT;
1366
1367 p = get_proc_task(inode);
1368 if (!p)
1369 return -ESRCH;
1370
1371 if (same_thread_group(current, p))
1372 set_task_comm(p, buffer);
1373 else
1374 count = -EINVAL;
1375
1376 put_task_struct(p);
1377
1378 return count;
1379}
1380
1381static int comm_show(struct seq_file *m, void *v)
1382{
1383 struct inode *inode = m->private;
1384 struct task_struct *p;
1385
1386 p = get_proc_task(inode);
1387 if (!p)
1388 return -ESRCH;
1389
1390 task_lock(p);
1391 seq_printf(m, "%s\n", p->comm);
1392 task_unlock(p);
1393
1394 put_task_struct(p);
1395
1396 return 0;
1397}
1398
1399static int comm_open(struct inode *inode, struct file *filp)
1400{
c6a34058 1401 return single_open(filp, comm_show, inode);
4614a696 1402}
1403
1404static const struct file_operations proc_pid_set_comm_operations = {
1405 .open = comm_open,
1406 .read = seq_read,
1407 .write = comm_write,
1408 .llseek = seq_lseek,
1409 .release = single_release,
1410};
1411
7773fbc5 1412static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
925d1c40
MH		 1413{
1414 struct task_struct *task;
1415 struct mm_struct *mm;
1416 struct file *exe_file;
1417
7773fbc5 1418 task = get_proc_task(dentry->d_inode);
925d1c40
MH		 1419 if (!task)
1420 return -ENOENT;
1421 mm = get_task_mm(task);
1422 put_task_struct(task);
1423 if (!mm)
1424 return -ENOENT;
1425 exe_file = get_mm_exe_file(mm);
1426 mmput(mm);
1427 if (exe_file) {
1428 *exe_path = exe_file->f_path;
1429 path_get(&exe_file->f_path);
1430 fput(exe_file);
1431 return 0;
1432 } else
1433 return -ENOENT;
1434}
1435
008b150a 1436static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1437{
1438 struct inode *inode = dentry->d_inode;
1439 int error = -EACCES;
1440
1441 /* We don't need a base pointer in the /proc filesystem */
1d957f9b 1442 path_put(&nd->path);
1da177e4 1443
778c1144
EB		 1444 /* Are we allowed to snoop on the tasks file descriptors? */
1445 if (!proc_fd_access_allowed(inode))
1da177e4 1446 goto out;
1da177e4 1447
7773fbc5 1448 error = PROC_I(inode)->op.proc_get_link(dentry, &nd->path);
1da177e4 1449out:
008b150a 1450 return ERR_PTR(error);
1da177e4
LT		 1451}
1452
3dcd25f3 1453static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1454{
e12ba74d 1455 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1456 char *pathname;
1da177e4
LT		 1457 int len;
1458
1459 if (!tmp)
1460 return -ENOMEM;
0c28f287 1461
7b2a69ba 1462 pathname = d_path(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1463 len = PTR_ERR(pathname);
1464 if (IS_ERR(pathname))
1da177e4 1465 goto out;
3dcd25f3 1466 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1467
1468 if (len > buflen)
1469 len = buflen;
3dcd25f3 1470 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1471 len = -EFAULT;
1472 out:
1473 free_page((unsigned long)tmp);
1474 return len;
1475}
1476
1477static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1478{
1479 int error = -EACCES;
1480 struct inode *inode = dentry->d_inode;
3dcd25f3 1481 struct path path;
1da177e4 1482
778c1144
EB		 1483 /* Are we allowed to snoop on the tasks file descriptors? */
1484 if (!proc_fd_access_allowed(inode))
1da177e4 1485 goto out;
1da177e4 1486
7773fbc5 1487 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1da177e4
LT		 1488 if (error)
1489 goto out;
1490
3dcd25f3
JB		 1491 error = do_proc_readlink(&path, buffer, buflen);
1492 path_put(&path);
1da177e4 1493out:
1da177e4
LT		 1494 return error;
1495}
1496
c5ef1c42 1497static const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1498 .readlink = proc_pid_readlink,
6d76fa58
LT		 1499 .follow_link = proc_pid_follow_link,
1500 .setattr = proc_setattr,
1da177e4
LT		 1501};
1502
28a6d671
EB		 1503
1504/* building an inode */
1505
1506static int task_dumpable(struct task_struct *task)
1da177e4 1507{
28a6d671
EB		 1508 int dumpable = 0;
1509 struct mm_struct *mm;
1da177e4 1510
28a6d671
EB		 1511 task_lock(task);
1512 mm = task->mm;
1513 if (mm)
6c5d5238 1514 dumpable = get_dumpable(mm);
28a6d671
EB		 1515 task_unlock(task);
1516 if(dumpable == 1)
1517 return 1;
1518 return 0;
1519}
1da177e4 1520
6b4e306a 1521struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1522{
1523 struct inode * inode;
1524 struct proc_inode *ei;
c69e8d9c 1525 const struct cred *cred;
1da177e4 1526
28a6d671 1527 /* We need a new inode */
1da177e4 1528
28a6d671
EB		 1529 inode = new_inode(sb);
1530 if (!inode)
1531 goto out;
1532
1533 /* Common stuff */
1534 ei = PROC_I(inode);
85fe4025 1535 inode->i_ino = get_next_ino();
28a6d671 1536 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
28a6d671
EB		 1537 inode->i_op = &proc_def_inode_operations;
1538
1539 /*
1540 * grab the reference to task.
1541 */
1a657f78 1542 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1543 if (!ei->pid)
1544 goto out_unlock;
1545
28a6d671 1546 if (task_dumpable(task)) {
c69e8d9c
DH		 1547 rcu_read_lock();
1548 cred = __task_cred(task);
1549 inode->i_uid = cred->euid;
1550 inode->i_gid = cred->egid;
1551 rcu_read_unlock();
1da177e4 1552 }
28a6d671
EB		 1553 security_task_to_inode(task, inode);
1554
1da177e4 1555out:
28a6d671
EB		 1556 return inode;
1557
1558out_unlock:
1559 iput(inode);
1560 return NULL;
1da177e4
LT		 1561}
1562
6b4e306a 1563int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1564{
1da177e4 1565 struct inode *inode = dentry->d_inode;
28a6d671 1566 struct task_struct *task;
c69e8d9c 1567 const struct cred *cred;
0499680a 1568 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
c69e8d9c 1569
28a6d671 1570 generic_fillattr(inode, stat);
1da177e4 1571
28a6d671
EB		 1572 rcu_read_lock();
1573 stat->uid = 0;
1574 stat->gid = 0;
1575 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1576 if (task) {
0499680a
VK		 1577 if (!has_pid_permissions(pid, task, 2)) {
1578 rcu_read_unlock();
1579 /*
1580 * This doesn't prevent learning whether PID exists,
1581 * it only makes getattr() consistent with readdir().
1582 */
1583 return -ENOENT;
1584 }
28a6d671
EB		 1585 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1586 task_dumpable(task)) {
c69e8d9c
DH		 1587 cred = __task_cred(task);
1588 stat->uid = cred->euid;
1589 stat->gid = cred->egid;
1da177e4
LT		 1590 }
1591 }
28a6d671 1592 rcu_read_unlock();
d6e71144 1593 return 0;
1da177e4
LT		 1594}
1595
1da177e4
LT		 1596/* dentry stuff */
1597
1598/*
1599 * Exceptional case: normally we are not allowed to unhash a busy
1600 * directory. In this case, however, we can do it - no aliasing problems
1601 * due to the way we treat inodes.
1602 *
1603 * Rewrite the inode's ownerships here because the owning task may have
1604 * performed a setuid(), etc.
99f89551
EB		 1605 *
1606 * Before the /proc/pid/status file was created the only way to read
1607 * the effective uid of a /process was to stat /proc/pid. Reading
1608 * /proc/pid/status is slow enough that procps and other packages
1609 * kept stating /proc/pid. To keep the rules in /proc simple I have
1610 * made this apply to all per process world readable and executable
1611 * directories.
1da177e4 1612 */
6b4e306a 1613int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1da177e4 1614{
34286d66
NP		 1615 struct inode *inode;
1616 struct task_struct *task;
c69e8d9c
DH		 1617 const struct cred *cred;
1618
34286d66
NP		 1619 if (nd && nd->flags & LOOKUP_RCU)
1620 return -ECHILD;
1621
1622 inode = dentry->d_inode;
1623 task = get_proc_task(inode);
1624
99f89551
EB		 1625 if (task) {
1626 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1627 task_dumpable(task)) {
c69e8d9c
DH		 1628 rcu_read_lock();
1629 cred = __task_cred(task);
1630 inode->i_uid = cred->euid;
1631 inode->i_gid = cred->egid;
1632 rcu_read_unlock();
1da177e4
LT		 1633 } else {
1634 inode->i_uid = 0;
1635 inode->i_gid = 0;
1636 }
9ee8ab9f 1637 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1638 security_task_to_inode(task, inode);
99f89551 1639 put_task_struct(task);
1da177e4
LT		 1640 return 1;
1641 }
1642 d_drop(dentry);
1643 return 0;
1644}
1645
fe15ce44 1646static int pid_delete_dentry(const struct dentry * dentry)
99f89551 1647{
28a6d671
EB		 1648 /* Is the task we represent dead?
1649 * If so, then don't put the dentry on the lru list,
1650 * kill it immediately.
1651 */
1652 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1653}
1654
6b4e306a 1655const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1656{
1657 .d_revalidate = pid_revalidate,
1658 .d_delete = pid_delete_dentry,
1659};
1660
1661/* Lookups */
1662
1c0d04c9
EB		 1663/*
1664 * Fill a directory entry.
1665 *
1666 * If possible create the dcache entry and derive our inode number and
1667 * file type from dcache entry.
1668 *
1669 * Since all of the proc inode numbers are dynamically generated, the inode
1670 * numbers do not exist until the inode is cache. This means creating the
1671 * the dcache entry in readdir is necessary to keep the inode numbers
1672 * reported by readdir in sync with the inode numbers reported
1673 * by stat.
1674 */
6b4e306a
EB		 1675int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1676 const char *name, int len,
c5141e6d 1677 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1678{
2fddfeef 1679 struct dentry *child, *dir = filp->f_path.dentry;
61a28784
EB		 1680 struct inode *inode;
1681 struct qstr qname;
1682 ino_t ino = 0;
1683 unsigned type = DT_UNKNOWN;
1684
1685 qname.name = name;
1686 qname.len = len;
1687 qname.hash = full_name_hash(name, len);
1688
1689 child = d_lookup(dir, &qname);
1690 if (!child) {
1691 struct dentry *new;
1692 new = d_alloc(dir, &qname);
1693 if (new) {
1694 child = instantiate(dir->d_inode, new, task, ptr);
1695 if (child)
1696 dput(new);
1697 else
1698 child = new;
1699 }
1700 }
1701 if (!child || IS_ERR(child) || !child->d_inode)
1702 goto end_instantiate;
1703 inode = child->d_inode;
1704 if (inode) {
1705 ino = inode->i_ino;
1706 type = inode->i_mode >> 12;
1707 }
1708 dput(child);
1709end_instantiate:
1710 if (!ino)
1711 ino = find_inode_number(dir, &qname);
1712 if (!ino)
1713 ino = 1;
1714 return filldir(dirent, name, len, filp->f_pos, ino, type);
1715}
1716
28a6d671
EB		 1717static unsigned name_to_int(struct dentry *dentry)
1718{
1719 const char *name = dentry->d_name.name;
1720 int len = dentry->d_name.len;
1721 unsigned n = 0;
1722
1723 if (len > 1 && *name == '0')
1724 goto out;
1725 while (len-- > 0) {
1726 unsigned c = *name++ - '0';
1727 if (c > 9)
1728 goto out;
1729 if (n >= (~0U-9)/10)
1730 goto out;
1731 n *= 10;
1732 n += c;
1733 }
1734 return n;
1735out:
1736 return ~0U;
1737}
1738
27932742
MS		 1739#define PROC_FDINFO_MAX 64
1740
3dcd25f3 1741static int proc_fd_info(struct inode *inode, struct path *path, char *info)
28a6d671 1742{
5e442a49
LT		 1743 struct task_struct *task = get_proc_task(inode);
1744 struct files_struct *files = NULL;
28a6d671
EB		 1745 struct file *file;
1746 int fd = proc_fd(inode);
aa6afca5 1747
5e442a49
LT		 1748 if (task) {
1749 files = get_files_struct(task);
1750 put_task_struct(task);
1751 }
1752 if (files) {
1753 /*
1754 * We are not taking a ref to the file structure, so we must
1755 * hold ->file_lock.
1756 */
1757 spin_lock(&files->file_lock);
1758 file = fcheck_files(files, fd);
1759 if (file) {
1760 unsigned int f_flags;
1761 struct fdtable *fdt;
1762
1763 fdt = files_fdtable(files);
1764 f_flags = file->f_flags & ~O_CLOEXEC;
1765 if (FD_ISSET(fd, fdt->close_on_exec))
1766 f_flags |= O_CLOEXEC;
1767
1768 if (path) {
1769 *path = file->f_path;
1770 path_get(&file->f_path);
1771 }
1772 if (info)
1773 snprintf(info, PROC_FDINFO_MAX,
1774 "pos:\t%lli\n"
1775 "flags:\t0%o\n",
1776 (long long) file->f_pos,
1777 f_flags);
1778 spin_unlock(&files->file_lock);
1779 put_files_struct(files);
1780 return 0;
99f89551 1781 }
5e442a49
LT		 1782 spin_unlock(&files->file_lock);
1783 put_files_struct(files);
1784 }
1785 return -ENOENT;
99f89551
EB		 1786}
1787
7773fbc5 1788static int proc_fd_link(struct dentry *dentry, struct path *path)
27932742 1789{
7773fbc5 1790 return proc_fd_info(dentry->d_inode, path, NULL);
27932742
MS		 1791}
1792
1da177e4
LT		 1793static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1794{
34286d66
NP		 1795 struct inode *inode;
1796 struct task_struct *task;
1797 int fd;
1da177e4 1798 struct files_struct *files;
c69e8d9c 1799 const struct cred *cred;
1da177e4 1800
34286d66
NP		 1801 if (nd && nd->flags & LOOKUP_RCU)
1802 return -ECHILD;
1803
1804 inode = dentry->d_inode;
1805 task = get_proc_task(inode);
1806 fd = proc_fd(inode);
1807
99f89551
EB		 1808 if (task) {
1809 files = get_files_struct(task);
1810 if (files) {
1811 rcu_read_lock();
1812 if (fcheck_files(files, fd)) {
1813 rcu_read_unlock();
1814 put_files_struct(files);
1815 if (task_dumpable(task)) {
c69e8d9c
DH		 1816 rcu_read_lock();
1817 cred = __task_cred(task);
1818 inode->i_uid = cred->euid;
1819 inode->i_gid = cred->egid;
1820 rcu_read_unlock();
99f89551
EB		 1821 } else {
1822 inode->i_uid = 0;
1823 inode->i_gid = 0;
1824 }
9ee8ab9f 1825 inode->i_mode &= ~(S_ISUID | S_ISGID);
99f89551
EB		 1826 security_task_to_inode(task, inode);
1827 put_task_struct(task);
1828 return 1;
1829 }
b835996f 1830 rcu_read_unlock();
1da177e4 1831 put_files_struct(files);
1da177e4 1832 }
99f89551 1833 put_task_struct(task);
1da177e4
LT		 1834 }
1835 d_drop(dentry);
1836 return 0;
1837}
1838
d72f71eb 1839static const struct dentry_operations tid_fd_dentry_operations =
1da177e4
LT		 1840{
1841 .d_revalidate = tid_fd_revalidate,
1842 .d_delete = pid_delete_dentry,
1843};
1844
444ceed8 1845static struct dentry *proc_fd_instantiate(struct inode *dir,
c5141e6d 1846 struct dentry *dentry, struct task_struct *task, const void *ptr)
1da177e4 1847{
c5141e6d 1848 unsigned fd = *(const unsigned *)ptr;
444ceed8
EB		 1849 struct file *file;
1850 struct files_struct *files;
1851 struct inode *inode;
1852 struct proc_inode *ei;
1853 struct dentry *error = ERR_PTR(-ENOENT);
1da177e4 1854
61a28784 1855 inode = proc_pid_make_inode(dir->i_sb, task);
1da177e4
LT		 1856 if (!inode)
1857 goto out;
1858 ei = PROC_I(inode);
aed7a6c4 1859 ei->fd = fd;
1da177e4
LT		 1860 files = get_files_struct(task);
1861 if (!files)
444ceed8 1862 goto out_iput;
1da177e4 1863 inode->i_mode = S_IFLNK;
ca99c1da
DS		 1864
1865 /*
1866 * We are not taking a ref to the file structure, so we must
1867 * hold ->file_lock.
1868 */
1869 spin_lock(&files->file_lock);
1da177e4
LT		 1870 file = fcheck_files(files, fd);
1871 if (!file)
444ceed8 1872 goto out_unlock;
aeb5d727 1873 if (file->f_mode & FMODE_READ)
1da177e4 1874 inode->i_mode |= S_IRUSR | S_IXUSR;
aeb5d727 1875 if (file->f_mode & FMODE_WRITE)
1da177e4 1876 inode->i_mode |= S_IWUSR | S_IXUSR;
ca99c1da 1877 spin_unlock(&files->file_lock);
1da177e4 1878 put_files_struct(files);
444ceed8 1879
5e442a49 1880 inode->i_op = &proc_pid_link_inode_operations;
1da177e4
LT		 1881 inode->i_size = 64;
1882 ei->op.proc_get_link = proc_fd_link;
fb045adb 1883 d_set_d_op(dentry, &tid_fd_dentry_operations);
1da177e4 1884 d_add(dentry, inode);
cd6a3ce9
EB		 1885 /* Close the race of the process dying before we return the dentry */
1886 if (tid_fd_revalidate(dentry, NULL))
444ceed8 1887 error = NULL;
1da177e4 1888
444ceed8
EB		 1889 out:
1890 return error;
1891out_unlock:
ca99c1da 1892 spin_unlock(&files->file_lock);
1da177e4 1893 put_files_struct(files);
444ceed8 1894out_iput:
1da177e4 1895 iput(inode);
cd6a3ce9 1896 goto out;
1da177e4
LT		 1897}
1898
27932742
MS		 1899static struct dentry *proc_lookupfd_common(struct inode *dir,
1900 struct dentry *dentry,
1901 instantiate_t instantiate)
444ceed8
EB		 1902{
1903 struct task_struct *task = get_proc_task(dir);
1904 unsigned fd = name_to_int(dentry);
1905 struct dentry *result = ERR_PTR(-ENOENT);
1906
1907 if (!task)
1908 goto out_no_task;
1909 if (fd == ~0U)
1910 goto out;
1911
27932742 1912 result = instantiate(dir, dentry, task, &fd);
444ceed8
EB		 1913out:
1914 put_task_struct(task);
1915out_no_task:
1916 return result;
1917}
1918
27932742
MS		 1919static int proc_readfd_common(struct file * filp, void * dirent,
1920 filldir_t filldir, instantiate_t instantiate)
28a6d671 1921{
2fddfeef 1922 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 1923 struct inode *inode = dentry->d_inode;
1924 struct task_struct *p = get_proc_task(inode);
457c2510 1925 unsigned int fd, ino;
28a6d671 1926 int retval;
28a6d671 1927 struct files_struct * files;
1da177e4 1928
28a6d671
EB		 1929 retval = -ENOENT;
1930 if (!p)
1931 goto out_no_task;
1932 retval = 0;
28a6d671
EB		 1933
1934 fd = filp->f_pos;
1935 switch (fd) {
1936 case 0:
1937 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
5e442a49 1938 goto out;
28a6d671
EB		 1939 filp->f_pos++;
1940 case 1:
1941 ino = parent_ino(dentry);
1942 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
5e442a49 1943 goto out;
28a6d671
EB		 1944 filp->f_pos++;
1945 default:
1946 files = get_files_struct(p);
1947 if (!files)
5e442a49 1948 goto out;
28a6d671 1949 rcu_read_lock();
28a6d671 1950 for (fd = filp->f_pos-2;
9b4f526c 1951 fd < files_fdtable(files)->max_fds;
28a6d671 1952 fd++, filp->f_pos++) {
27932742
MS		 1953 char name[PROC_NUMBUF];
1954 int len;
28a6d671
EB		 1955
1956 if (!fcheck_files(files, fd))
1957 continue;
1958 rcu_read_unlock();
1959
27932742
MS		 1960 len = snprintf(name, sizeof(name), "%d", fd);
1961 if (proc_fill_cache(filp, dirent, filldir,
1962 name, len, instantiate,
1963 p, &fd) < 0) {
28a6d671
EB		 1964 rcu_read_lock();
1965 break;
1966 }
1967 rcu_read_lock();
1968 }
1969 rcu_read_unlock();
1970 put_files_struct(files);
1971 }
1972out:
1973 put_task_struct(p);
1974out_no_task:
1975 return retval;
1976}
1977
27932742
MS		 1978static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
1979 struct nameidata *nd)
1980{
1981 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
1982}
1983
1984static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
1985{
1986 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
1987}
1988
1989static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
1990 size_t len, loff_t *ppos)
1991{
1992 char tmp[PROC_FDINFO_MAX];
3dcd25f3 1993 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
27932742
MS		 1994 if (!err)
1995 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
1996 return err;
1997}
1998
1999static const struct file_operations proc_fdinfo_file_operations = {
87df8424 2000 .open = nonseekable_open,
27932742 2001 .read = proc_fdinfo_read,
6038f373 2002 .llseek = no_llseek,
27932742
MS		 2003};
2004
00977a59 2005static const struct file_operations proc_fd_operations = {
28a6d671
EB		 2006 .read = generic_read_dir,
2007 .readdir = proc_readfd,
6038f373 2008 .llseek = default_llseek,
1da177e4
LT		 2009};
2010
640708a2
PE		 2011#ifdef CONFIG_CHECKPOINT_RESTORE
2012
2013/*
2014 * dname_to_vma_addr - maps a dentry name into two unsigned longs
2015 * which represent vma start and end addresses.
2016 */
2017static int dname_to_vma_addr(struct dentry *dentry,
2018 unsigned long *start, unsigned long *end)
2019{
2020 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
2021 return -EINVAL;
2022
2023 return 0;
2024}
2025
2026static int map_files_d_revalidate(struct dentry *dentry, struct nameidata *nd)
2027{
2028 unsigned long vm_start, vm_end;
2029 bool exact_vma_exists = false;
2030 struct mm_struct *mm = NULL;
2031 struct task_struct *task;
2032 const struct cred *cred;
2033 struct inode *inode;
2034 int status = 0;
2035
2036 if (nd && nd->flags & LOOKUP_RCU)
2037 return -ECHILD;
2038
2039 if (!capable(CAP_SYS_ADMIN)) {
2040 status = -EACCES;
2041 goto out_notask;
2042 }
2043
2044 inode = dentry->d_inode;
2045 task = get_proc_task(inode);
2046 if (!task)
2047 goto out_notask;
2048
2049 if (!ptrace_may_access(task, PTRACE_MODE_READ))
2050 goto out;
2051
2052 mm = get_task_mm(task);
2053 if (!mm)
2054 goto out;
2055
2056 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2057 down_read(&mm->mmap_sem);
2058 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
2059 up_read(&mm->mmap_sem);
2060 }
2061
2062 mmput(mm);
2063
2064 if (exact_vma_exists) {
2065 if (task_dumpable(task)) {
2066 rcu_read_lock();
2067 cred = __task_cred(task);
2068 inode->i_uid = cred->euid;
2069 inode->i_gid = cred->egid;
2070 rcu_read_unlock();
2071 } else {
2072 inode->i_uid = 0;
2073 inode->i_gid = 0;
2074 }
2075 security_task_to_inode(task, inode);
2076 status = 1;
2077 }
2078
2079out:
2080 put_task_struct(task);
2081
2082out_notask:
2083 if (status <= 0)
2084 d_drop(dentry);
2085
2086 return status;
2087}
2088
2089static const struct dentry_operations tid_map_files_dentry_operations = {
2090 .d_revalidate = map_files_d_revalidate,
2091 .d_delete = pid_delete_dentry,
2092};
2093
2094static int proc_map_files_get_link(struct dentry *dentry, struct path *path)
2095{
2096 unsigned long vm_start, vm_end;
2097 struct vm_area_struct *vma;
2098 struct task_struct *task;
2099 struct mm_struct *mm;
2100 int rc;
2101
2102 rc = -ENOENT;
2103 task = get_proc_task(dentry->d_inode);
2104 if (!task)
2105 goto out;
2106
2107 mm = get_task_mm(task);
2108 put_task_struct(task);
2109 if (!mm)
2110 goto out;
2111
2112 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2113 if (rc)
2114 goto out_mmput;
2115
2116 down_read(&mm->mmap_sem);
2117 vma = find_exact_vma(mm, vm_start, vm_end);
2118 if (vma && vma->vm_file) {
2119 *path = vma->vm_file->f_path;
2120 path_get(path);
2121 rc = 0;
2122 }
2123 up_read(&mm->mmap_sem);
2124
2125out_mmput:
2126 mmput(mm);
2127out:
2128 return rc;
2129}
2130
2131struct map_files_info {
2132 struct file *file;
2133 unsigned long len;
2134 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
2135};
2136
2137static struct dentry *
2138proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2139 struct task_struct *task, const void *ptr)
2140{
2141 const struct file *file = ptr;
2142 struct proc_inode *ei;
2143 struct inode *inode;
2144
2145 if (!file)
2146 return ERR_PTR(-ENOENT);
2147
2148 inode = proc_pid_make_inode(dir->i_sb, task);
2149 if (!inode)
2150 return ERR_PTR(-ENOENT);
2151
2152 ei = PROC_I(inode);
2153 ei->op.proc_get_link = proc_map_files_get_link;
2154
2155 inode->i_op = &proc_pid_link_inode_operations;
2156 inode->i_size = 64;
2157 inode->i_mode = S_IFLNK;
2158
2159 if (file->f_mode & FMODE_READ)
2160 inode->i_mode |= S_IRUSR;
2161 if (file->f_mode & FMODE_WRITE)
2162 inode->i_mode |= S_IWUSR;
2163
2164 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2165 d_add(dentry, inode);
2166
2167 return NULL;
2168}
2169
2170static struct dentry *proc_map_files_lookup(struct inode *dir,
2171 struct dentry *dentry, struct nameidata *nd)
2172{
2173 unsigned long vm_start, vm_end;
2174 struct vm_area_struct *vma;
2175 struct task_struct *task;
2176 struct dentry *result;
2177 struct mm_struct *mm;
2178
2179 result = ERR_PTR(-EACCES);
2180 if (!capable(CAP_SYS_ADMIN))
2181 goto out;
2182
2183 result = ERR_PTR(-ENOENT);
2184 task = get_proc_task(dir);
2185 if (!task)
2186 goto out;
2187
2188 result = ERR_PTR(-EACCES);
2189 if (lock_trace(task))
2190 goto out_put_task;
2191
2192 result = ERR_PTR(-ENOENT);
2193 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2194 goto out_unlock;
2195
2196 mm = get_task_mm(task);
2197 if (!mm)
2198 goto out_unlock;
2199
2200 down_read(&mm->mmap_sem);
2201 vma = find_exact_vma(mm, vm_start, vm_end);
2202 if (!vma)
2203 goto out_no_vma;
2204
2205 result = proc_map_files_instantiate(dir, dentry, task, vma->vm_file);
2206
2207out_no_vma:
2208 up_read(&mm->mmap_sem);
2209 mmput(mm);
2210out_unlock:
2211 unlock_trace(task);
2212out_put_task:
2213 put_task_struct(task);
2214out:
2215 return result;
2216}
2217
2218static const struct inode_operations proc_map_files_inode_operations = {
2219 .lookup = proc_map_files_lookup,
2220 .permission = proc_fd_permission,
2221 .setattr = proc_setattr,
2222};
2223
2224static int
2225proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
2226{
2227 struct dentry *dentry = filp->f_path.dentry;
2228 struct inode *inode = dentry->d_inode;
2229 struct vm_area_struct *vma;
2230 struct task_struct *task;
2231 struct mm_struct *mm;
2232 ino_t ino;
2233 int ret;
2234
2235 ret = -EACCES;
2236 if (!capable(CAP_SYS_ADMIN))
2237 goto out;
2238
2239 ret = -ENOENT;
2240 task = get_proc_task(inode);
2241 if (!task)
2242 goto out;
2243
2244 ret = -EACCES;
2245 if (lock_trace(task))
2246 goto out_put_task;
2247
2248 ret = 0;
2249 switch (filp->f_pos) {
2250 case 0:
2251 ino = inode->i_ino;
2252 if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0)
2253 goto out_unlock;
2254 filp->f_pos++;
2255 case 1:
2256 ino = parent_ino(dentry);
2257 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2258 goto out_unlock;
2259 filp->f_pos++;
2260 default:
2261 {
2262 unsigned long nr_files, pos, i;
2263 struct flex_array *fa = NULL;
2264 struct map_files_info info;
2265 struct map_files_info *p;
2266
2267 mm = get_task_mm(task);
2268 if (!mm)
2269 goto out_unlock;
2270 down_read(&mm->mmap_sem);
2271
2272 nr_files = 0;
2273
2274 /*
2275 * We need two passes here:
2276 *
2277 * 1) Collect vmas of mapped files with mmap_sem taken
2278 * 2) Release mmap_sem and instantiate entries
2279 *
2280 * otherwise we get lockdep complained, since filldir()
2281 * routine might require mmap_sem taken in might_fault().
2282 */
2283
2284 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2285 if (vma->vm_file && ++pos > filp->f_pos)
2286 nr_files++;
2287 }
2288
2289 if (nr_files) {
2290 fa = flex_array_alloc(sizeof(info), nr_files,
2291 GFP_KERNEL);
2292 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2293 GFP_KERNEL)) {
2294 ret = -ENOMEM;
2295 if (fa)
2296 flex_array_free(fa);
2297 up_read(&mm->mmap_sem);
2298 mmput(mm);
2299 goto out_unlock;
2300 }
2301 for (i = 0, vma = mm->mmap, pos = 2; vma;
2302 vma = vma->vm_next) {
2303 if (!vma->vm_file)
2304 continue;
2305 if (++pos <= filp->f_pos)
2306 continue;
2307
2308 get_file(vma->vm_file);
2309 info.file = vma->vm_file;
2310 info.len = snprintf(info.name,
2311 sizeof(info.name), "%lx-%lx",
2312 vma->vm_start, vma->vm_end);
2313 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2314 BUG();
2315 }
2316 }
2317 up_read(&mm->mmap_sem);
2318
2319 for (i = 0; i < nr_files; i++) {
2320 p = flex_array_get(fa, i);
2321 ret = proc_fill_cache(filp, dirent, filldir,
2322 p->name, p->len,
2323 proc_map_files_instantiate,
2324 task, p->file);
2325 if (ret)
2326 break;
2327 filp->f_pos++;
2328 fput(p->file);
2329 }
2330 for (; i < nr_files; i++) {
2331 /*
2332 * In case of error don't forget
2333 * to put rest of file refs.
2334 */
2335 p = flex_array_get(fa, i);
2336 fput(p->file);
2337 }
2338 if (fa)
2339 flex_array_free(fa);
2340 mmput(mm);
2341 }
2342 }
2343
2344out_unlock:
2345 unlock_trace(task);
2346out_put_task:
2347 put_task_struct(task);
2348out:
2349 return ret;
2350}
2351
2352static const struct file_operations proc_map_files_operations = {
2353 .read = generic_read_dir,
2354 .readdir = proc_map_files_readdir,
2355 .llseek = default_llseek,
2356};
2357
2358#endif /* CONFIG_CHECKPOINT_RESTORE */
2359
8948e11f
AD		 2360/*
2361 * /proc/pid/fd needs a special permission handler so that a process can still
2362 * access /proc/self/fd after it has executed a setuid().
2363 */
10556cb2 2364static int proc_fd_permission(struct inode *inode, int mask)
8948e11f 2365{
2830ba7f 2366 int rv = generic_permission(inode, mask);
8948e11f
AD		 2367 if (rv == 0)
2368 return 0;
2369 if (task_pid(current) == proc_pid(inode))
2370 rv = 0;
2371 return rv;
2372}
2373
1da177e4
LT		 2374/*
2375 * proc directories can do almost nothing..
2376 */
c5ef1c42 2377static const struct inode_operations proc_fd_inode_operations = {
1da177e4 2378 .lookup = proc_lookupfd,
8948e11f 2379 .permission = proc_fd_permission,
6d76fa58 2380 .setattr = proc_setattr,
1da177e4
LT		 2381};
2382
27932742
MS		 2383static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2384 struct dentry *dentry, struct task_struct *task, const void *ptr)
2385{
2386 unsigned fd = *(unsigned *)ptr;
2387 struct inode *inode;
2388 struct proc_inode *ei;
2389 struct dentry *error = ERR_PTR(-ENOENT);
2390
2391 inode = proc_pid_make_inode(dir->i_sb, task);
2392 if (!inode)
2393 goto out;
2394 ei = PROC_I(inode);
2395 ei->fd = fd;
2396 inode->i_mode = S_IFREG | S_IRUSR;
2397 inode->i_fop = &proc_fdinfo_file_operations;
fb045adb 2398 d_set_d_op(dentry, &tid_fd_dentry_operations);
27932742
MS		 2399 d_add(dentry, inode);
2400 /* Close the race of the process dying before we return the dentry */
2401 if (tid_fd_revalidate(dentry, NULL))
2402 error = NULL;
2403
2404 out:
2405 return error;
2406}
2407
2408static struct dentry *proc_lookupfdinfo(struct inode *dir,
2409 struct dentry *dentry,
2410 struct nameidata *nd)
2411{
2412 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2413}
2414
2415static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2416{
2417 return proc_readfd_common(filp, dirent, filldir,
2418 proc_fdinfo_instantiate);
2419}
2420
2421static const struct file_operations proc_fdinfo_operations = {
2422 .read = generic_read_dir,
2423 .readdir = proc_readfdinfo,
6038f373 2424 .llseek = default_llseek,
27932742
MS		 2425};
2426
2427/*
2428 * proc directories can do almost nothing..
2429 */
2430static const struct inode_operations proc_fdinfo_inode_operations = {
2431 .lookup = proc_lookupfdinfo,
2432 .setattr = proc_setattr,
2433};
2434
2435
444ceed8 2436static struct dentry *proc_pident_instantiate(struct inode *dir,
c5141e6d 2437 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2438{
c5141e6d 2439 const struct pid_entry *p = ptr;
444ceed8
EB		 2440 struct inode *inode;
2441 struct proc_inode *ei;
bd6daba9 2442 struct dentry *error = ERR_PTR(-ENOENT);
444ceed8 2443
61a28784 2444 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2445 if (!inode)
2446 goto out;
2447
2448 ei = PROC_I(inode);
2449 inode->i_mode = p->mode;
2450 if (S_ISDIR(inode->i_mode))
bfe86848 2451 set_nlink(inode, 2); /* Use getattr to fix if necessary */
444ceed8
EB		 2452 if (p->iop)
2453 inode->i_op = p->iop;
2454 if (p->fop)
2455 inode->i_fop = p->fop;
2456 ei->op = p->op;
fb045adb 2457 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2458 d_add(dentry, inode);
2459 /* Close the race of the process dying before we return the dentry */
2460 if (pid_revalidate(dentry, NULL))
2461 error = NULL;
2462out:
2463 return error;
2464}
2465
1da177e4
LT		 2466static struct dentry *proc_pident_lookup(struct inode *dir,
2467 struct dentry *dentry,
c5141e6d 2468 const struct pid_entry *ents,
7bcd6b0e 2469 unsigned int nents)
1da177e4 2470{
cd6a3ce9 2471 struct dentry *error;
99f89551 2472 struct task_struct *task = get_proc_task(dir);
c5141e6d 2473 const struct pid_entry *p, *last;
1da177e4 2474
cd6a3ce9 2475 error = ERR_PTR(-ENOENT);
1da177e4 2476
99f89551
EB		 2477 if (!task)
2478 goto out_no_task;
1da177e4 2479
20cdc894
EB		 2480 /*
2481 * Yes, it does not scale. And it should not. Don't add
2482 * new entries into /proc/<tgid>/ without very good reasons.
2483 */
7bcd6b0e
EB		 2484 last = &ents[nents - 1];
2485 for (p = ents; p <= last; p++) {
1da177e4
LT		 2486 if (p->len != dentry->d_name.len)
2487 continue;
2488 if (!memcmp(dentry->d_name.name, p->name, p->len))
2489 break;
2490 }
7bcd6b0e 2491 if (p > last)
1da177e4
LT		 2492 goto out;
2493
444ceed8 2494 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2495out:
99f89551
EB		 2496 put_task_struct(task);
2497out_no_task:
cd6a3ce9 2498 return error;
1da177e4
LT		 2499}
2500
c5141e6d
ED		 2501static int proc_pident_fill_cache(struct file *filp, void *dirent,
2502 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2503{
2504 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2505 proc_pident_instantiate, task, p);
2506}
2507
28a6d671
EB		 2508static int proc_pident_readdir(struct file *filp,
2509 void *dirent, filldir_t filldir,
c5141e6d 2510 const struct pid_entry *ents, unsigned int nents)
28a6d671
EB		 2511{
2512 int i;
2fddfeef 2513 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2514 struct inode *inode = dentry->d_inode;
2515 struct task_struct *task = get_proc_task(inode);
c5141e6d 2516 const struct pid_entry *p, *last;
28a6d671
EB		 2517 ino_t ino;
2518 int ret;
2519
2520 ret = -ENOENT;
2521 if (!task)
61a28784 2522 goto out_no_task;
28a6d671
EB		 2523
2524 ret = 0;
28a6d671
EB		 2525 i = filp->f_pos;
2526 switch (i) {
2527 case 0:
2528 ino = inode->i_ino;
2529 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2530 goto out;
2531 i++;
2532 filp->f_pos++;
2533 /* fall through */
2534 case 1:
2535 ino = parent_ino(dentry);
2536 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2537 goto out;
2538 i++;
2539 filp->f_pos++;
2540 /* fall through */
2541 default:
2542 i -= 2;
2543 if (i >= nents) {
2544 ret = 1;
2545 goto out;
2546 }
2547 p = ents + i;
7bcd6b0e
EB		 2548 last = &ents[nents - 1];
2549 while (p <= last) {
61a28784 2550 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
28a6d671
EB		 2551 goto out;
2552 filp->f_pos++;
2553 p++;
2554 }
2555 }
2556
2557 ret = 1;
2558out:
61a28784
EB		 2559 put_task_struct(task);
2560out_no_task:
28a6d671 2561 return ret;
1da177e4
LT		 2562}
2563
28a6d671
EB		 2564#ifdef CONFIG_SECURITY
2565static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2566 size_t count, loff_t *ppos)
2567{
2fddfeef 2568 struct inode * inode = file->f_path.dentry->d_inode;
04ff9708 2569 char *p = NULL;
28a6d671
EB		 2570 ssize_t length;
2571 struct task_struct *task = get_proc_task(inode);
2572
28a6d671 2573 if (!task)
04ff9708 2574 return -ESRCH;
28a6d671
EB		 2575
2576 length = security_getprocattr(task,
2fddfeef 2577 (char*)file->f_path.dentry->d_name.name,
04ff9708 2578 &p);
28a6d671 2579 put_task_struct(task);
04ff9708
AV		 2580 if (length > 0)
2581 length = simple_read_from_buffer(buf, count, ppos, p, length);
2582 kfree(p);
28a6d671 2583 return length;
1da177e4
LT		 2584}
2585
28a6d671
EB		 2586static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2587 size_t count, loff_t *ppos)
2588{
2fddfeef 2589 struct inode * inode = file->f_path.dentry->d_inode;
28a6d671
EB		 2590 char *page;
2591 ssize_t length;
2592 struct task_struct *task = get_proc_task(inode);
2593
2594 length = -ESRCH;
2595 if (!task)
2596 goto out_no_task;
2597 if (count > PAGE_SIZE)
2598 count = PAGE_SIZE;
2599
2600 /* No partial writes. */
2601 length = -EINVAL;
2602 if (*ppos != 0)
2603 goto out;
2604
2605 length = -ENOMEM;
e12ba74d 2606 page = (char*)__get_free_page(GFP_TEMPORARY);
28a6d671
EB		 2607 if (!page)
2608 goto out;
2609
2610 length = -EFAULT;
2611 if (copy_from_user(page, buf, count))
2612 goto out_free;
2613
107db7c7 2614 /* Guard against adverse ptrace interaction */
9b1bf12d 2615 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2616 if (length < 0)
2617 goto out_free;
2618
28a6d671 2619 length = security_setprocattr(task,
2fddfeef 2620 (char*)file->f_path.dentry->d_name.name,
28a6d671 2621 (void*)page, count);
9b1bf12d 2622 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671
EB		 2623out_free:
2624 free_page((unsigned long) page);
2625out:
2626 put_task_struct(task);
2627out_no_task:
2628 return length;
2629}
2630
00977a59 2631static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2632 .read = proc_pid_attr_read,
2633 .write = proc_pid_attr_write,
87df8424 2634 .llseek = generic_file_llseek,
28a6d671
EB		 2635};
2636
c5141e6d 2637static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2638 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2639 REG("prev", S_IRUGO, proc_pid_attr_operations),
2640 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2641 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2642 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2643 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2644};
2645
72d9dcfc 2646static int proc_attr_dir_readdir(struct file * filp,
28a6d671
EB		 2647 void * dirent, filldir_t filldir)
2648{
2649 return proc_pident_readdir(filp,dirent,filldir,
72d9dcfc 2650 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2651}
2652
00977a59 2653static const struct file_operations proc_attr_dir_operations = {
1da177e4 2654 .read = generic_read_dir,
72d9dcfc 2655 .readdir = proc_attr_dir_readdir,
6038f373 2656 .llseek = default_llseek,
1da177e4
LT		 2657};
2658
72d9dcfc 2659static struct dentry *proc_attr_dir_lookup(struct inode *dir,
28a6d671
EB		 2660 struct dentry *dentry, struct nameidata *nd)
2661{
7bcd6b0e
EB		 2662 return proc_pident_lookup(dir, dentry,
2663 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2664}
2665
c5ef1c42 2666static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2667 .lookup = proc_attr_dir_lookup,
99f89551 2668 .getattr = pid_getattr,
6d76fa58 2669 .setattr = proc_setattr,
1da177e4
LT		 2670};
2671
28a6d671
EB		 2672#endif
2673
698ba7b5 2674#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2675static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2676 size_t count, loff_t *ppos)
2677{
2678 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2679 struct mm_struct *mm;
2680 char buffer[PROC_NUMBUF];
2681 size_t len;
2682 int ret;
2683
2684 if (!task)
2685 return -ESRCH;
2686
2687 ret = 0;
2688 mm = get_task_mm(task);
2689 if (mm) {
2690 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2691 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2692 MMF_DUMP_FILTER_SHIFT));
2693 mmput(mm);
2694 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2695 }
2696
2697 put_task_struct(task);
2698
2699 return ret;
2700}
2701
2702static ssize_t proc_coredump_filter_write(struct file *file,
2703 const char __user *buf,
2704 size_t count,
2705 loff_t *ppos)
2706{
2707 struct task_struct *task;
2708 struct mm_struct *mm;
2709 char buffer[PROC_NUMBUF], *end;
2710 unsigned int val;
2711 int ret;
2712 int i;
2713 unsigned long mask;
2714
2715 ret = -EFAULT;
2716 memset(buffer, 0, sizeof(buffer));
2717 if (count > sizeof(buffer) - 1)
2718 count = sizeof(buffer) - 1;
2719 if (copy_from_user(buffer, buf, count))
2720 goto out_no_task;
2721
2722 ret = -EINVAL;
2723 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2724 if (*end == '\n')
2725 end++;
2726 if (end - buffer == 0)
2727 goto out_no_task;
2728
2729 ret = -ESRCH;
2730 task = get_proc_task(file->f_dentry->d_inode);
2731 if (!task)
2732 goto out_no_task;
2733
2734 ret = end - buffer;
2735 mm = get_task_mm(task);
2736 if (!mm)
2737 goto out_no_mm;
2738
2739 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2740 if (val & mask)
2741 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2742 else
2743 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2744 }
2745
2746 mmput(mm);
2747 out_no_mm:
2748 put_task_struct(task);
2749 out_no_task:
2750 return ret;
2751}
2752
2753static const struct file_operations proc_coredump_filter_operations = {
2754 .read = proc_coredump_filter_read,
2755 .write = proc_coredump_filter_write,
87df8424 2756 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2757};
2758#endif
2759
28a6d671
EB		 2760/*
2761 * /proc/self:
2762 */
2763static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2764 int buflen)
2765{
488e5bc4 2766 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2767 pid_t tgid = task_tgid_nr_ns(current, ns);
28a6d671 2768 char tmp[PROC_NUMBUF];
b55fcb22 2769 if (!tgid)
488e5bc4 2770 return -ENOENT;
b55fcb22 2771 sprintf(tmp, "%d", tgid);
28a6d671
EB		 2772 return vfs_readlink(dentry,buffer,buflen,tmp);
2773}
2774
2775static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2776{
488e5bc4 2777 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2778 pid_t tgid = task_tgid_nr_ns(current, ns);
7fee4868
AV		 2779 char *name = ERR_PTR(-ENOENT);
2780 if (tgid) {
2781 name = __getname();
2782 if (!name)
2783 name = ERR_PTR(-ENOMEM);
2784 else
2785 sprintf(name, "%d", tgid);
2786 }
2787 nd_set_link(nd, name);
2788 return NULL;
2789}
2790
2791static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2792 void *cookie)
2793{
2794 char *s = nd_get_link(nd);
2795 if (!IS_ERR(s))
2796 __putname(s);
28a6d671
EB		 2797}
2798
c5ef1c42 2799static const struct inode_operations proc_self_inode_operations = {
28a6d671
EB		 2800 .readlink = proc_self_readlink,
2801 .follow_link = proc_self_follow_link,
7fee4868 2802 .put_link = proc_self_put_link,
28a6d671
EB		 2803};
2804
801199ce
EB		 2805/*
2806 * proc base
2807 *
2808 * These are the directory entries in the root directory of /proc
2809 * that properly belong to the /proc filesystem, as they describe
2810 * describe something that is process related.
2811 */
c5141e6d 2812static const struct pid_entry proc_base_stuff[] = {
61a28784 2813 NOD("self", S_IFLNK|S_IRWXUGO,
801199ce 2814 &proc_self_inode_operations, NULL, {}),
801199ce
EB		 2815};
2816
444ceed8 2817static struct dentry *proc_base_instantiate(struct inode *dir,
c5141e6d 2818 struct dentry *dentry, struct task_struct *task, const void *ptr)
801199ce 2819{
c5141e6d 2820 const struct pid_entry *p = ptr;
801199ce 2821 struct inode *inode;
801199ce 2822 struct proc_inode *ei;
73d36460 2823 struct dentry *error;
801199ce
EB		 2824
2825 /* Allocate the inode */
2826 error = ERR_PTR(-ENOMEM);
2827 inode = new_inode(dir->i_sb);
2828 if (!inode)
2829 goto out;
2830
2831 /* Initialize the inode */
2832 ei = PROC_I(inode);
85fe4025 2833 inode->i_ino = get_next_ino();
801199ce 2834 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
801199ce
EB		 2835
2836 /*
2837 * grab the reference to the task.
2838 */
1a657f78 2839 ei->pid = get_task_pid(task, PIDTYPE_PID);
801199ce
EB		 2840 if (!ei->pid)
2841 goto out_iput;
2842
801199ce
EB		 2843 inode->i_mode = p->mode;
2844 if (S_ISDIR(inode->i_mode))
bfe86848 2845 set_nlink(inode, 2);
801199ce
EB		 2846 if (S_ISLNK(inode->i_mode))
2847 inode->i_size = 64;
2848 if (p->iop)
2849 inode->i_op = p->iop;
2850 if (p->fop)
2851 inode->i_fop = p->fop;
2852 ei->op = p->op;
801199ce
EB		 2853 d_add(dentry, inode);
2854 error = NULL;
2855out:
801199ce
EB		 2856 return error;
2857out_iput:
2858 iput(inode);
2859 goto out;
2860}
2861
444ceed8
EB		 2862static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2863{
2864 struct dentry *error;
2865 struct task_struct *task = get_proc_task(dir);
c5141e6d 2866 const struct pid_entry *p, *last;
444ceed8
EB		 2867
2868 error = ERR_PTR(-ENOENT);
2869
2870 if (!task)
2871 goto out_no_task;
2872
2873 /* Lookup the directory entry */
7bcd6b0e
EB		 2874 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2875 for (p = proc_base_stuff; p <= last; p++) {
444ceed8
EB		 2876 if (p->len != dentry->d_name.len)
2877 continue;
2878 if (!memcmp(dentry->d_name.name, p->name, p->len))
2879 break;
2880 }
7bcd6b0e 2881 if (p > last)
444ceed8
EB		 2882 goto out;
2883
2884 error = proc_base_instantiate(dir, dentry, task, p);
2885
2886out:
2887 put_task_struct(task);
2888out_no_task:
2889 return error;
2890}
2891
c5141e6d
ED		 2892static int proc_base_fill_cache(struct file *filp, void *dirent,
2893 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2894{
2895 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2896 proc_base_instantiate, task, p);
2897}
2898
aba76fdb 2899#ifdef CONFIG_TASK_IO_ACCOUNTING
297c5d92
AR		 2900static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2901{
940389b8 2902 struct task_io_accounting acct = task->ioac;
5995477a 2903 unsigned long flags;
293eb1e7 2904 int result;
5995477a 2905
293eb1e7
VK		 2906 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2907 if (result)
2908 return result;
2909
2910 if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
2911 result = -EACCES;
2912 goto out_unlock;
2913 }
1d1221f3 2914
5995477a
AR		 2915 if (whole && lock_task_sighand(task, &flags)) {
2916 struct task_struct *t = task;
2917
2918 task_io_accounting_add(&acct, &task->signal->ioac);
2919 while_each_thread(task, t)
2920 task_io_accounting_add(&acct, &t->ioac);
2921
2922 unlock_task_sighand(task, &flags);
297c5d92 2923 }
293eb1e7 2924 result = sprintf(buffer,
aba76fdb
AM		 2925 "rchar: %llu\n"
2926 "wchar: %llu\n"
2927 "syscr: %llu\n"
2928 "syscw: %llu\n"
2929 "read_bytes: %llu\n"
2930 "write_bytes: %llu\n"
2931 "cancelled_write_bytes: %llu\n",
7c44319d
AB		 2932 (unsigned long long)acct.rchar,
2933 (unsigned long long)acct.wchar,
2934 (unsigned long long)acct.syscr,
2935 (unsigned long long)acct.syscw,
2936 (unsigned long long)acct.read_bytes,
2937 (unsigned long long)acct.write_bytes,
2938 (unsigned long long)acct.cancelled_write_bytes);
293eb1e7
VK		 2939out_unlock:
2940 mutex_unlock(&task->signal->cred_guard_mutex);
2941 return result;
297c5d92
AR		 2942}
2943
2944static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2945{
2946 return do_io_accounting(task, buffer, 0);
aba76fdb 2947}
297c5d92
AR		 2948
2949static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2950{
2951 return do_io_accounting(task, buffer, 1);
2952}
2953#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2954
47830723
KC		 2955static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2956 struct pid *pid, struct task_struct *task)
2957{
a9712bc1
AV		 2958 int err = lock_trace(task);
2959 if (!err) {
2960 seq_printf(m, "%08x\n", task->personality);
2961 unlock_trace(task);
2962 }
2963 return err;
47830723
KC		 2964}
2965
28a6d671
EB		 2966/*
2967 * Thread groups
2968 */
00977a59 2969static const struct file_operations proc_task_operations;
c5ef1c42 2970static const struct inode_operations proc_task_inode_operations;
20cdc894 2971
c5141e6d 2972static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2973 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2974 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
640708a2
PE		 2975#ifdef CONFIG_CHECKPOINT_RESTORE
2976 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
2977#endif
631f9c18 2978 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 2979 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
b2211a36 2980#ifdef CONFIG_NET
631f9c18 2981 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 2982#endif
631f9c18
AD		 2983 REG("environ", S_IRUSR, proc_environ_operations),
2984 INF("auxv", S_IRUSR, proc_pid_auxv),
2985 ONE("status", S_IRUGO, proc_pid_status),
a9712bc1 2986 ONE("personality", S_IRUGO, proc_pid_personality),
3036e7b4 2987 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 2988#ifdef CONFIG_SCHED_DEBUG
631f9c18 2989 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
5091faa4
MG		 2990#endif
2991#ifdef CONFIG_SCHED_AUTOGROUP
2992 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
ebcb6734 2993#endif
4614a696 2994 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 2995#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
a9712bc1 2996 INF("syscall", S_IRUGO, proc_pid_syscall),
43ae34cb 2997#endif
631f9c18
AD		 2998 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2999 ONE("stat", S_IRUGO, proc_tgid_stat),
3000 ONE("statm", S_IRUGO, proc_pid_statm),
3001 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3002#ifdef CONFIG_NUMA
631f9c18 3003 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3004#endif
631f9c18
AD		 3005 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3006 LNK("cwd", proc_cwd_link),
3007 LNK("root", proc_root_link),
3008 LNK("exe", proc_exe_link),
3009 REG("mounts", S_IRUGO, proc_mounts_operations),
3010 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3011 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 3012#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3013 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3014 REG("smaps", S_IRUGO, proc_smaps_operations),
ca6b0bf0 3015 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 3016#endif
3017#ifdef CONFIG_SECURITY
631f9c18 3018 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3019#endif
3020#ifdef CONFIG_KALLSYMS
631f9c18 3021 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3022#endif
2ec220e2 3023#ifdef CONFIG_STACKTRACE
a9712bc1 3024 ONE("stack", S_IRUGO, proc_pid_stack),
28a6d671
EB		 3025#endif
3026#ifdef CONFIG_SCHEDSTATS
631f9c18 3027 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3028#endif
9745512c 3029#ifdef CONFIG_LATENCYTOP
631f9c18 3030 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3031#endif
8793d854 3032#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3033 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3034#endif
3035#ifdef CONFIG_CGROUPS
631f9c18 3036 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3037#endif
631f9c18
AD		 3038 INF("oom_score", S_IRUGO, proc_oom_score),
3039 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3040 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3041#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 3042 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3043 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3044#endif
f4f154fd 3045#ifdef CONFIG_FAULT_INJECTION
631f9c18 3046 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3047#endif
698ba7b5 3048#ifdef CONFIG_ELF_CORE
631f9c18 3049 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 3050#endif
aba76fdb 3051#ifdef CONFIG_TASK_IO_ACCOUNTING
1d1221f3 3052 INF("io", S_IRUSR, proc_tgid_io_accounting),
aba76fdb 3053#endif
f133ecca
CM		 3054#ifdef CONFIG_HARDWALL
3055 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3056#endif
28a6d671 3057};
1da177e4 3058
28a6d671 3059static int proc_tgid_base_readdir(struct file * filp,
1da177e4
LT		 3060 void * dirent, filldir_t filldir)
3061{
3062 return proc_pident_readdir(filp,dirent,filldir,
28a6d671 3063 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 3064}
3065
00977a59 3066static const struct file_operations proc_tgid_base_operations = {
1da177e4 3067 .read = generic_read_dir,
28a6d671 3068 .readdir = proc_tgid_base_readdir,
6038f373 3069 .llseek = default_llseek,
1da177e4
LT		 3070};
3071
28a6d671 3072static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3073 return proc_pident_lookup(dir, dentry,
3074 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 3075}
3076
c5ef1c42 3077static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 3078 .lookup = proc_tgid_base_lookup,
99f89551 3079 .getattr = pid_getattr,
6d76fa58 3080 .setattr = proc_setattr,
0499680a 3081 .permission = proc_pid_permission,
1da177e4 3082};
1da177e4 3083
60347f67 3084static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 3085{
48e6484d 3086 struct dentry *dentry, *leader, *dir;
8578cea7 3087 char buf[PROC_NUMBUF];
48e6484d
EB		 3088 struct qstr name;
3089
3090 name.name = buf;
60347f67
PE		 3091 name.len = snprintf(buf, sizeof(buf), "%d", pid);
3092 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 3093 if (dentry) {
29f12ca3 3094 shrink_dcache_parent(dentry);
48e6484d
EB		 3095 d_drop(dentry);
3096 dput(dentry);
3097 }
1da177e4 3098
48e6484d 3099 name.name = buf;
60347f67
PE		 3100 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
3101 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 3102 if (!leader)
3103 goto out;
1da177e4 3104
48e6484d
EB		 3105 name.name = "task";
3106 name.len = strlen(name.name);
3107 dir = d_hash_and_lookup(leader, &name);
3108 if (!dir)
3109 goto out_put_leader;
3110
3111 name.name = buf;
60347f67 3112 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 3113 dentry = d_hash_and_lookup(dir, &name);
3114 if (dentry) {
3115 shrink_dcache_parent(dentry);
3116 d_drop(dentry);
3117 dput(dentry);
1da177e4 3118 }
48e6484d
EB		 3119
3120 dput(dir);
3121out_put_leader:
3122 dput(leader);
3123out:
3124 return;
1da177e4
LT		 3125}
3126
0895e91d
RD		 3127/**
3128 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3129 * @task: task that should be flushed.
3130 *
3131 * When flushing dentries from proc, one needs to flush them from global
60347f67 3132 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 3133 * in. This call is supposed to do all of this job.
3134 *
3135 * Looks in the dcache for
3136 * /proc/@pid
3137 * /proc/@tgid/task/@pid
3138 * if either directory is present flushes it and all of it'ts children
3139 * from the dcache.
3140 *
3141 * It is safe and reasonable to cache /proc entries for a task until
3142 * that task exits. After that they just clog up the dcache with
3143 * useless entries, possibly causing useful dcache entries to be
3144 * flushed instead. This routine is proved to flush those useless
3145 * dcache entries at process exit time.
3146 *
3147 * NOTE: This routine is just an optimization so it does not guarantee
3148 * that no dcache entries will exist at process exit time it
3149 * just makes it very unlikely that any will persist.
60347f67
PE		 3150 */
3151
3152void proc_flush_task(struct task_struct *task)
3153{
9fcc2d15 3154 int i;
9b4d1cbe 3155 struct pid *pid, *tgid;
130f77ec
PE		 3156 struct upid *upid;
3157
130f77ec 3158 pid = task_pid(task);
9b4d1cbe 3159 tgid = task_tgid(task);
130f77ec 3160
9fcc2d15 3161 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 3162 upid = &pid->numbers[i];
3163 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 3164 tgid->numbers[i].nr);
130f77ec 3165 }
6f4e6433
PE		 3166
3167 upid = &pid->numbers[pid->level];
3168 if (upid->nr == 1)
3169 pid_ns_release_proc(upid->ns);
60347f67
PE		 3170}
3171
9711ef99
AB		 3172static struct dentry *proc_pid_instantiate(struct inode *dir,
3173 struct dentry * dentry,
c5141e6d 3174 struct task_struct *task, const void *ptr)
444ceed8
EB		 3175{
3176 struct dentry *error = ERR_PTR(-ENOENT);
3177 struct inode *inode;
3178
61a28784 3179 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3180 if (!inode)
3181 goto out;
3182
3183 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3184 inode->i_op = &proc_tgid_base_inode_operations;
3185 inode->i_fop = &proc_tgid_base_operations;
3186 inode->i_flags|=S_IMMUTABLE;
aed54175 3187
bfe86848
MS		 3188 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff,
3189 ARRAY_SIZE(tgid_base_stuff)));
444ceed8 3190
fb045adb 3191 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3192
3193 d_add(dentry, inode);
3194 /* Close the race of the process dying before we return the dentry */
3195 if (pid_revalidate(dentry, NULL))
3196 error = NULL;
3197out:
3198 return error;
3199}
3200
1da177e4
LT		 3201struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3202{
73d36460 3203 struct dentry *result;
1da177e4 3204 struct task_struct *task;
1da177e4 3205 unsigned tgid;
b488893a 3206 struct pid_namespace *ns;
1da177e4 3207
801199ce
EB		 3208 result = proc_base_lookup(dir, dentry);
3209 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
3210 goto out;
3211
1da177e4
LT		 3212 tgid = name_to_int(dentry);
3213 if (tgid == ~0U)
3214 goto out;
3215
b488893a 3216 ns = dentry->d_sb->s_fs_info;
de758734 3217 rcu_read_lock();
b488893a 3218 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 3219 if (task)
3220 get_task_struct(task);
de758734 3221 rcu_read_unlock();
1da177e4
LT		 3222 if (!task)
3223 goto out;
3224
444ceed8 3225 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 3226 put_task_struct(task);
1da177e4 3227out:
cd6a3ce9 3228 return result;
1da177e4
LT		 3229}
3230
1da177e4 3231/*
0804ef4b 3232 * Find the first task with tgid >= tgid
0bc58a91 3233 *
1da177e4 3234 */
19fd4bb2
EB		 3235struct tgid_iter {
3236 unsigned int tgid;
0804ef4b 3237 struct task_struct *task;
19fd4bb2
EB		 3238};
3239static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3240{
0804ef4b 3241 struct pid *pid;
1da177e4 3242
19fd4bb2
EB		 3243 if (iter.task)
3244 put_task_struct(iter.task);
454cc105 3245 rcu_read_lock();
0804ef4b 3246retry:
19fd4bb2
EB		 3247 iter.task = NULL;
3248 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 3249 if (pid) {
19fd4bb2
EB		 3250 iter.tgid = pid_nr_ns(pid, ns);
3251 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 3252 /* What we to know is if the pid we have find is the
3253 * pid of a thread_group_leader. Testing for task
3254 * being a thread_group_leader is the obvious thing
3255 * todo but there is a window when it fails, due to
3256 * the pid transfer logic in de_thread.
3257 *
3258 * So we perform the straight forward test of seeing
3259 * if the pid we have found is the pid of a thread
3260 * group leader, and don't worry if the task we have
3261 * found doesn't happen to be a thread group leader.
3262 * As we don't care in the case of readdir.
3263 */
19fd4bb2
EB		 3264 if (!iter.task || !has_group_leader_pid(iter.task)) {
3265 iter.tgid += 1;
0804ef4b 3266 goto retry;
19fd4bb2
EB		 3267 }
3268 get_task_struct(iter.task);
0bc58a91 3269 }
454cc105 3270 rcu_read_unlock();
19fd4bb2 3271 return iter;
1da177e4
LT		 3272}
3273
7bcd6b0e 3274#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
0804ef4b 3275
61a28784 3276static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
19fd4bb2 3277 struct tgid_iter iter)
61a28784
EB		 3278{
3279 char name[PROC_NUMBUF];
19fd4bb2 3280 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
61a28784 3281 return proc_fill_cache(filp, dirent, filldir, name, len,
19fd4bb2 3282 proc_pid_instantiate, iter.task, NULL);
61a28784
EB		 3283}
3284
0499680a
VK		 3285static int fake_filldir(void *buf, const char *name, int namelen,
3286 loff_t offset, u64 ino, unsigned d_type)
3287{
3288 return 0;
3289}
3290
1da177e4
LT		 3291/* for the /proc/ directory itself, after non-process stuff has been done */
3292int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3293{
d8bdc59f
LT		 3294 unsigned int nr;
3295 struct task_struct *reaper;
19fd4bb2 3296 struct tgid_iter iter;
b488893a 3297 struct pid_namespace *ns;
0499680a 3298 filldir_t __filldir;
1da177e4 3299
d8bdc59f
LT		 3300 if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
3301 goto out_no_task;
3302 nr = filp->f_pos - FIRST_PROCESS_ENTRY;
3303
3304 reaper = get_proc_task(filp->f_path.dentry->d_inode);
61a28784
EB		 3305 if (!reaper)
3306 goto out_no_task;
3307
7bcd6b0e 3308 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
c5141e6d 3309 const struct pid_entry *p = &proc_base_stuff[nr];
61a28784 3310 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
801199ce 3311 goto out;
1da177e4
LT		 3312 }
3313
b488893a 3314 ns = filp->f_dentry->d_sb->s_fs_info;
19fd4bb2
EB		 3315 iter.task = NULL;
3316 iter.tgid = filp->f_pos - TGID_OFFSET;
3317 for (iter = next_tgid(ns, iter);
3318 iter.task;
3319 iter.tgid += 1, iter = next_tgid(ns, iter)) {
0499680a
VK		 3320 if (has_pid_permissions(ns, iter.task, 2))
3321 __filldir = filldir;
3322 else
3323 __filldir = fake_filldir;
3324
19fd4bb2 3325 filp->f_pos = iter.tgid + TGID_OFFSET;
0499680a 3326 if (proc_pid_fill_cache(filp, dirent, __filldir, iter) < 0) {
19fd4bb2 3327 put_task_struct(iter.task);
0804ef4b 3328 goto out;
1da177e4 3329 }
0bc58a91 3330 }
0804ef4b
EB		 3331 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3332out:
61a28784
EB		 3333 put_task_struct(reaper);
3334out_no_task:
0bc58a91
EB		 3335 return 0;
3336}
1da177e4 3337
28a6d671
EB		 3338/*
3339 * Tasks
3340 */
c5141e6d 3341static const struct pid_entry tid_base_stuff[] = {
631f9c18 3342 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3343 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 3344 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
631f9c18
AD		 3345 REG("environ", S_IRUSR, proc_environ_operations),
3346 INF("auxv", S_IRUSR, proc_pid_auxv),
3347 ONE("status", S_IRUGO, proc_pid_status),
a9712bc1 3348 ONE("personality", S_IRUGO, proc_pid_personality),
3036e7b4 3349 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3350#ifdef CONFIG_SCHED_DEBUG
631f9c18 3351 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3352#endif
4614a696 3353 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3354#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
a9712bc1 3355 INF("syscall", S_IRUGO, proc_pid_syscall),
43ae34cb 3356#endif
631f9c18
AD		 3357 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3358 ONE("stat", S_IRUGO, proc_tid_stat),
3359 ONE("statm", S_IRUGO, proc_pid_statm),
3360 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3361#ifdef CONFIG_NUMA
631f9c18 3362 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3363#endif
631f9c18
AD		 3364 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3365 LNK("cwd", proc_cwd_link),
3366 LNK("root", proc_root_link),
3367 LNK("exe", proc_exe_link),
3368 REG("mounts", S_IRUGO, proc_mounts_operations),
3369 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3370#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3371 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3372 REG("smaps", S_IRUGO, proc_smaps_operations),
ca6b0bf0 3373 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 3374#endif
3375#ifdef CONFIG_SECURITY
631f9c18 3376 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3377#endif
3378#ifdef CONFIG_KALLSYMS
631f9c18 3379 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3380#endif
2ec220e2 3381#ifdef CONFIG_STACKTRACE
a9712bc1 3382 ONE("stack", S_IRUGO, proc_pid_stack),
28a6d671
EB		 3383#endif
3384#ifdef CONFIG_SCHEDSTATS
631f9c18 3385 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3386#endif
9745512c 3387#ifdef CONFIG_LATENCYTOP
631f9c18 3388 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3389#endif
8793d854 3390#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3391 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3392#endif
3393#ifdef CONFIG_CGROUPS
631f9c18 3394 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3395#endif
631f9c18
AD		 3396 INF("oom_score", S_IRUGO, proc_oom_score),
3397 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3398 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3399#ifdef CONFIG_AUDITSYSCALL
631f9c18 3400 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
26ec3c64 3401 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3402#endif
f4f154fd 3403#ifdef CONFIG_FAULT_INJECTION
631f9c18 3404 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3405#endif
297c5d92 3406#ifdef CONFIG_TASK_IO_ACCOUNTING
1d1221f3 3407 INF("io", S_IRUSR, proc_tid_io_accounting),
297c5d92 3408#endif
f133ecca
CM		 3409#ifdef CONFIG_HARDWALL
3410 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3411#endif
28a6d671
EB		 3412};
3413
3414static int proc_tid_base_readdir(struct file * filp,
3415 void * dirent, filldir_t filldir)
3416{
3417 return proc_pident_readdir(filp,dirent,filldir,
3418 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3419}
3420
3421static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3422 return proc_pident_lookup(dir, dentry,
3423 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3424}
3425
00977a59 3426static const struct file_operations proc_tid_base_operations = {
28a6d671
EB		 3427 .read = generic_read_dir,
3428 .readdir = proc_tid_base_readdir,
6038f373 3429 .llseek = default_llseek,
28a6d671
EB		 3430};
3431
c5ef1c42 3432static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3433 .lookup = proc_tid_base_lookup,
3434 .getattr = pid_getattr,
3435 .setattr = proc_setattr,
3436};
3437
444ceed8 3438static struct dentry *proc_task_instantiate(struct inode *dir,
c5141e6d 3439 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8
EB		 3440{
3441 struct dentry *error = ERR_PTR(-ENOENT);
3442 struct inode *inode;
61a28784 3443 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3444
3445 if (!inode)
3446 goto out;
3447 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3448 inode->i_op = &proc_tid_base_inode_operations;
3449 inode->i_fop = &proc_tid_base_operations;
3450 inode->i_flags|=S_IMMUTABLE;
aed54175 3451
bfe86848
MS		 3452 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff,
3453 ARRAY_SIZE(tid_base_stuff)));
444ceed8 3454
fb045adb 3455 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3456
3457 d_add(dentry, inode);
3458 /* Close the race of the process dying before we return the dentry */
3459 if (pid_revalidate(dentry, NULL))
3460 error = NULL;
3461out:
3462 return error;
3463}
3464
28a6d671
EB		 3465static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3466{
3467 struct dentry *result = ERR_PTR(-ENOENT);
3468 struct task_struct *task;
3469 struct task_struct *leader = get_proc_task(dir);
28a6d671 3470 unsigned tid;
b488893a 3471 struct pid_namespace *ns;
28a6d671
EB		 3472
3473 if (!leader)
3474 goto out_no_task;
3475
3476 tid = name_to_int(dentry);
3477 if (tid == ~0U)
3478 goto out;
3479
b488893a 3480 ns = dentry->d_sb->s_fs_info;
28a6d671 3481 rcu_read_lock();
b488893a 3482 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3483 if (task)
3484 get_task_struct(task);
3485 rcu_read_unlock();
3486 if (!task)
3487 goto out;
bac0abd6 3488 if (!same_thread_group(leader, task))
28a6d671
EB		 3489 goto out_drop_task;
3490
444ceed8 3491 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3492out_drop_task:
3493 put_task_struct(task);
3494out:
3495 put_task_struct(leader);
3496out_no_task:
3497 return result;
3498}
3499
0bc58a91
EB		 3500/*
3501 * Find the first tid of a thread group to return to user space.
3502 *
3503 * Usually this is just the thread group leader, but if the users
3504 * buffer was too small or there was a seek into the middle of the
3505 * directory we have more work todo.
3506 *
3507 * In the case of a short read we start with find_task_by_pid.
3508 *
3509 * In the case of a seek we start with the leader and walk nr
3510 * threads past it.
3511 */
cc288738 3512static struct task_struct *first_tid(struct task_struct *leader,
b488893a 3513 int tid, int nr, struct pid_namespace *ns)
0bc58a91 3514{
a872ff0c 3515 struct task_struct *pos;
1da177e4 3516
cc288738 3517 rcu_read_lock();
0bc58a91
EB		 3518 /* Attempt to start with the pid of a thread */
3519 if (tid && (nr > 0)) {
b488893a 3520 pos = find_task_by_pid_ns(tid, ns);
a872ff0c
ON		 3521 if (pos && (pos->group_leader == leader))
3522 goto found;
0bc58a91 3523 }
1da177e4 3524
0bc58a91 3525 /* If nr exceeds the number of threads there is nothing todo */
a872ff0c
ON		 3526 pos = NULL;
3527 if (nr && nr >= get_nr_threads(leader))
3528 goto out;
1da177e4 3529
a872ff0c
ON		 3530 /* If we haven't found our starting place yet start
3531 * with the leader and walk nr threads forward.
0bc58a91 3532 */
a872ff0c
ON		 3533 for (pos = leader; nr > 0; --nr) {
3534 pos = next_thread(pos);
3535 if (pos == leader) {
3536 pos = NULL;
3537 goto out;
3538 }
1da177e4 3539 }
a872ff0c
ON		 3540found:
3541 get_task_struct(pos);
3542out:
cc288738 3543 rcu_read_unlock();
0bc58a91
EB		 3544 return pos;
3545}
3546
3547/*
3548 * Find the next thread in the thread list.
3549 * Return NULL if there is an error or no next thread.
3550 *
3551 * The reference to the input task_struct is released.
3552 */
3553static struct task_struct *next_tid(struct task_struct *start)
3554{
c1df7fb8 3555 struct task_struct *pos = NULL;
cc288738 3556 rcu_read_lock();
c1df7fb8 3557 if (pid_alive(start)) {
0bc58a91 3558 pos = next_thread(start);
c1df7fb8
ON		 3559 if (thread_group_leader(pos))
3560 pos = NULL;
3561 else
3562 get_task_struct(pos);
3563 }
cc288738 3564 rcu_read_unlock();
0bc58a91
EB		 3565 put_task_struct(start);
3566 return pos;
1da177e4
LT		 3567}
3568
61a28784
EB		 3569static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3570 struct task_struct *task, int tid)
3571{
3572 char name[PROC_NUMBUF];
3573 int len = snprintf(name, sizeof(name), "%d", tid);
3574 return proc_fill_cache(filp, dirent, filldir, name, len,
3575 proc_task_instantiate, task, NULL);
3576}
3577
1da177e4
LT		 3578/* for the /proc/TGID/task/ directories */
3579static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3580{
2fddfeef 3581 struct dentry *dentry = filp->f_path.dentry;
1da177e4 3582 struct inode *inode = dentry->d_inode;
7d895244 3583 struct task_struct *leader = NULL;
0bc58a91 3584 struct task_struct *task;
1da177e4
LT		 3585 int retval = -ENOENT;
3586 ino_t ino;
0bc58a91 3587 int tid;
b488893a 3588 struct pid_namespace *ns;
1da177e4 3589
7d895244
GC		 3590 task = get_proc_task(inode);
3591 if (!task)
3592 goto out_no_task;
3593 rcu_read_lock();
3594 if (pid_alive(task)) {
3595 leader = task->group_leader;
3596 get_task_struct(leader);
3597 }
3598 rcu_read_unlock();
3599 put_task_struct(task);
99f89551
EB		 3600 if (!leader)
3601 goto out_no_task;
1da177e4
LT		 3602 retval = 0;
3603
ee568b25 3604 switch ((unsigned long)filp->f_pos) {
1da177e4
LT		 3605 case 0:
3606 ino = inode->i_ino;
ee6f779b 3607 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3608 goto out;
ee6f779b 3609 filp->f_pos++;
1da177e4
LT		 3610 /* fall through */
3611 case 1:
3612 ino = parent_ino(dentry);
ee6f779b 3613 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3614 goto out;
ee6f779b 3615 filp->f_pos++;
1da177e4
LT		 3616 /* fall through */
3617 }
3618
0bc58a91
EB		 3619 /* f_version caches the tgid value that the last readdir call couldn't
3620 * return. lseek aka telldir automagically resets f_version to 0.
3621 */
b488893a 3622 ns = filp->f_dentry->d_sb->s_fs_info;
2b47c361 3623 tid = (int)filp->f_version;
0bc58a91 3624 filp->f_version = 0;
ee6f779b 3625 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
0bc58a91 3626 task;
ee6f779b 3627 task = next_tid(task), filp->f_pos++) {
b488893a 3628 tid = task_pid_nr_ns(task, ns);
61a28784 3629 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
0bc58a91
EB		 3630 /* returning this tgid failed, save it as the first
3631 * pid for the next readir call */
2b47c361 3632 filp->f_version = (u64)tid;
0bc58a91 3633 put_task_struct(task);
1da177e4 3634 break;
0bc58a91 3635 }
1da177e4
LT		 3636 }
3637out:
99f89551
EB		 3638 put_task_struct(leader);
3639out_no_task:
1da177e4
LT		 3640 return retval;
3641}
6e66b52b
EB		 3642
3643static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3644{
3645 struct inode *inode = dentry->d_inode;
99f89551 3646 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3647 generic_fillattr(inode, stat);
3648
99f89551 3649 if (p) {
99f89551 3650 stat->nlink += get_nr_threads(p);
99f89551 3651 put_task_struct(p);
6e66b52b
EB		 3652 }
3653
3654 return 0;
3655}
28a6d671 3656
c5ef1c42 3657static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3658 .lookup = proc_task_lookup,
3659 .getattr = proc_task_getattr,
3660 .setattr = proc_setattr,
0499680a 3661 .permission = proc_pid_permission,
28a6d671
EB		 3662};
3663
00977a59 3664static const struct file_operations proc_task_operations = {
28a6d671
EB		 3665 .read = generic_read_dir,
3666 .readdir = proc_task_readdir,
6038f373 3667 .llseek = default_llseek,
28a6d671 3668};
Linux kernel - Deliverables
This page took 0.874731 seconds and 5 git commands to generate.