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1da177e4
LT		 1/*
2 * linux/fs/proc/base.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * proc base directory handling functions
7 *
8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
9 * Instead of using magical inumbers to determine the kind of object
10 * we allocate and fill in-core inodes upon lookup. They don't even
11 * go into icache. We cache the reference to task_struct upon lookup too.
12 * Eventually it should become a filesystem in its own. We don't use the
13 * rest of procfs anymore.
e070ad49
ML		 14 *
15 *
16 * Changelog:
17 * 17-Jan-2005
18 * Allan Bezerra
19 * Bruna Moreira <bruna.moreira@indt.org.br>
20 * Edjard Mota <edjard.mota@indt.org.br>
21 * Ilias Biris <ilias.biris@indt.org.br>
22 * Mauricio Lin <mauricio.lin@indt.org.br>
23 *
24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
25 *
26 * A new process specific entry (smaps) included in /proc. It shows the
27 * size of rss for each memory area. The maps entry lacks information
28 * about physical memory size (rss) for each mapped file, i.e.,
29 * rss information for executables and library files.
30 * This additional information is useful for any tools that need to know
31 * about physical memory consumption for a process specific library.
32 *
33 * Changelog:
34 * 21-Feb-2005
35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
36 * Pud inclusion in the page table walking.
37 *
38 * ChangeLog:
39 * 10-Mar-2005
40 * 10LE Instituto Nokia de Tecnologia - INdT:
41 * A better way to walks through the page table as suggested by Hugh Dickins.
42 *
43 * Simo Piiroinen <simo.piiroinen@nokia.com>:
44 * Smaps information related to shared, private, clean and dirty pages.
45 *
46 * Paul Mundt <paul.mundt@nokia.com>:
47 * Overall revision about smaps.
1da177e4
LT		 48 */
49
50#include <asm/uaccess.h>
51
1da177e4
LT		 52#include <linux/errno.h>
53#include <linux/time.h>
54#include <linux/proc_fs.h>
55#include <linux/stat.h>
5995477a 56#include <linux/task_io_accounting_ops.h>
1da177e4 57#include <linux/init.h>
16f7e0fe 58#include <linux/capability.h>
1da177e4 59#include <linux/file.h>
9f3acc31 60#include <linux/fdtable.h>
1da177e4
LT		 61#include <linux/string.h>
62#include <linux/seq_file.h>
63#include <linux/namei.h>
6b3286ed 64#include <linux/mnt_namespace.h>
1da177e4 65#include <linux/mm.h>
a63d83f4 66#include <linux/swap.h>
b835996f 67#include <linux/rcupdate.h>
1da177e4 68#include <linux/kallsyms.h>
2ec220e2 69#include <linux/stacktrace.h>
d85f50d5 70#include <linux/resource.h>
5096add8 71#include <linux/module.h>
1da177e4
LT		 72#include <linux/mount.h>
73#include <linux/security.h>
74#include <linux/ptrace.h>
0d094efe 75#include <linux/tracehook.h>
a424316c 76#include <linux/cgroup.h>
1da177e4
LT		 77#include <linux/cpuset.h>
78#include <linux/audit.h>
5addc5dd 79#include <linux/poll.h>
1651e14e 80#include <linux/nsproxy.h>
8ac773b4 81#include <linux/oom.h>
3cb4a0bb 82#include <linux/elf.h>
60347f67 83#include <linux/pid_namespace.h>
5ad4e53b 84#include <linux/fs_struct.h>
5a0e3ad6 85#include <linux/slab.h>
1da177e4
LT		 86#include "internal.h"
87
0f2fe20f
EB		 88/* NOTE:
89 * Implementing inode permission operations in /proc is almost
90 * certainly an error. Permission checks need to happen during
91 * each system call not at open time. The reason is that most of
92 * what we wish to check for permissions in /proc varies at runtime.
93 *
94 * The classic example of a problem is opening file descriptors
95 * in /proc for a task before it execs a suid executable.
96 */
97
1da177e4 98struct pid_entry {
1da177e4 99 char *name;
c5141e6d 100 int len;
1da177e4 101 mode_t mode;
c5ef1c42 102 const struct inode_operations *iop;
00977a59 103 const struct file_operations *fop;
20cdc894 104 union proc_op op;
1da177e4
LT		 105};
106
61a28784 107#define NOD(NAME, MODE, IOP, FOP, OP) { \
20cdc894 108 .name = (NAME), \
c5141e6d 109 .len = sizeof(NAME) - 1, \
20cdc894
EB		 110 .mode = MODE, \
111 .iop = IOP, \
112 .fop = FOP, \
113 .op = OP, \
114}
115
631f9c18
AD		 116#define DIR(NAME, MODE, iops, fops) \
117 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
118#define LNK(NAME, get_link) \
61a28784 119 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
20cdc894 120 &proc_pid_link_inode_operations, NULL, \
631f9c18
AD		 121 { .proc_get_link = get_link } )
122#define REG(NAME, MODE, fops) \
123 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
124#define INF(NAME, MODE, read) \
61a28784 125 NOD(NAME, (S_IFREG|(MODE)), \
20cdc894 126 NULL, &proc_info_file_operations, \
631f9c18
AD		 127 { .proc_read = read } )
128#define ONE(NAME, MODE, show) \
be614086
EB		 129 NOD(NAME, (S_IFREG|(MODE)), \
130 NULL, &proc_single_file_operations, \
631f9c18 131 { .proc_show = show } )
1da177e4 132
aed54175
VN		 133/*
134 * Count the number of hardlinks for the pid_entry table, excluding the .
135 * and .. links.
136 */
137static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
138 unsigned int n)
139{
140 unsigned int i;
141 unsigned int count;
142
143 count = 0;
144 for (i = 0; i < n; ++i) {
145 if (S_ISDIR(entries[i].mode))
146 ++count;
147 }
148
149 return count;
150}
151
f7ad3c6b 152static int get_task_root(struct task_struct *task, struct path *root)
1da177e4 153{
7c2c7d99
HD		 154 int result = -ENOENT;
155
0494f6ec 156 task_lock(task);
f7ad3c6b
MS		 157 if (task->fs) {
158 get_fs_root(task->fs, root);
7c2c7d99
HD		 159 result = 0;
160 }
0494f6ec 161 task_unlock(task);
7c2c7d99 162 return result;
0494f6ec
MS		 163}
164
3dcd25f3 165static int proc_cwd_link(struct inode *inode, struct path *path)
0494f6ec 166{
99f89551 167 struct task_struct *task = get_proc_task(inode);
0494f6ec 168 int result = -ENOENT;
99f89551
EB		 169
170 if (task) {
f7ad3c6b
MS		 171 task_lock(task);
172 if (task->fs) {
173 get_fs_pwd(task->fs, path);
174 result = 0;
175 }
176 task_unlock(task);
99f89551
EB		 177 put_task_struct(task);
178 }
1da177e4
LT		 179 return result;
180}
181
3dcd25f3 182static int proc_root_link(struct inode *inode, struct path *path)
1da177e4 183{
99f89551 184 struct task_struct *task = get_proc_task(inode);
1da177e4 185 int result = -ENOENT;
99f89551
EB		 186
187 if (task) {
f7ad3c6b 188 result = get_task_root(task, path);
99f89551
EB		 189 put_task_struct(task);
190 }
1da177e4
LT		 191 return result;
192}
193
638fa202
RM		 194/*
195 * Return zero if current may access user memory in @task, -error if not.
196 */
197static int check_mem_permission(struct task_struct *task)
198{
199 /*
200 * A task can always look at itself, in case it chooses
201 * to use system calls instead of load instructions.
202 */
203 if (task == current)
204 return 0;
205
206 /*
207 * If current is actively ptrace'ing, and would also be
208 * permitted to freshly attach with ptrace now, permit it.
209 */
0d094efe
RM		 210 if (task_is_stopped_or_traced(task)) {
211 int match;
212 rcu_read_lock();
213 match = (tracehook_tracer_task(task) == current);
214 rcu_read_unlock();
215 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
216 return 0;
217 }
638fa202
RM		 218
219 /*
220 * Noone else is allowed.
221 */
222 return -EPERM;
223}
1da177e4 224
831830b5
AV		 225struct mm_struct *mm_for_maps(struct task_struct *task)
226{
704b836c
ON		 227 struct mm_struct *mm;
228
9b1bf12d 229 if (mutex_lock_killable(&task->signal->cred_guard_mutex))
704b836c 230 return NULL;
00f89d21 231
704b836c
ON		 232 mm = get_task_mm(task);
233 if (mm && mm != current->mm &&
234 !ptrace_may_access(task, PTRACE_MODE_READ)) {
235 mmput(mm);
236 mm = NULL;
13f0feaf 237 }
9b1bf12d 238 mutex_unlock(&task->signal->cred_guard_mutex);
704b836c 239
831830b5 240 return mm;
831830b5
AV		 241}
242
1da177e4
LT		 243static int proc_pid_cmdline(struct task_struct *task, char * buffer)
244{
245 int res = 0;
246 unsigned int len;
247 struct mm_struct *mm = get_task_mm(task);
248 if (!mm)
249 goto out;
250 if (!mm->arg_end)
251 goto out_mm; /* Shh! No looking before we're done */
252
253 len = mm->arg_end - mm->arg_start;
254
255 if (len > PAGE_SIZE)
256 len = PAGE_SIZE;
257
258 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
259
260 // If the nul at the end of args has been overwritten, then
261 // assume application is using setproctitle(3).
262 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
263 len = strnlen(buffer, res);
264 if (len < res) {
265 res = len;
266 } else {
267 len = mm->env_end - mm->env_start;
268 if (len > PAGE_SIZE - res)
269 len = PAGE_SIZE - res;
270 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
271 res = strnlen(buffer, res);
272 }
273 }
274out_mm:
275 mmput(mm);
276out:
277 return res;
278}
279
280static int proc_pid_auxv(struct task_struct *task, char *buffer)
281{
282 int res = 0;
283 struct mm_struct *mm = get_task_mm(task);
284 if (mm) {
285 unsigned int nwords = 0;
dfe6b7d9 286 do {
1da177e4 287 nwords += 2;
dfe6b7d9 288 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1da177e4
LT		 289 res = nwords * sizeof(mm->saved_auxv[0]);
290 if (res > PAGE_SIZE)
291 res = PAGE_SIZE;
292 memcpy(buffer, mm->saved_auxv, res);
293 mmput(mm);
294 }
295 return res;
296}
297
298
299#ifdef CONFIG_KALLSYMS
300/*
301 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
302 * Returns the resolved symbol. If that fails, simply return the address.
303 */
304static int proc_pid_wchan(struct task_struct *task, char *buffer)
305{
ffb45122 306 unsigned long wchan;
9281acea 307 char symname[KSYM_NAME_LEN];
1da177e4
LT		 308
309 wchan = get_wchan(task);
310
9d65cb4a 311 if (lookup_symbol_name(wchan, symname) < 0)
f83ce3e6
JE		 312 if (!ptrace_may_access(task, PTRACE_MODE_READ))
313 return 0;
314 else
315 return sprintf(buffer, "%lu", wchan);
9d65cb4a
AD		 316 else
317 return sprintf(buffer, "%s", symname);
1da177e4
LT		 318}
319#endif /* CONFIG_KALLSYMS */
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;
330 int i;
331
332 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
333 if (!entries)
334 return -ENOMEM;
335
336 trace.nr_entries = 0;
337 trace.max_entries = MAX_STACK_TRACE_DEPTH;
338 trace.entries = entries;
339 trace.skip = 0;
340 save_stack_trace_tsk(task, &trace);
341
342 for (i = 0; i < trace.nr_entries; i++) {
343 seq_printf(m, "[<%p>] %pS\n",
344 (void *)entries[i], (void *)entries[i]);
345 }
346 kfree(entries);
347
348 return 0;
349}
350#endif
351
1da177e4
LT		 352#ifdef CONFIG_SCHEDSTATS
353/*
354 * Provides /proc/PID/schedstat
355 */
356static int proc_pid_schedstat(struct task_struct *task, char *buffer)
357{
172ba844 358 return sprintf(buffer, "%llu %llu %lu\n",
826e08b0
IM		 359 (unsigned long long)task->se.sum_exec_runtime,
360 (unsigned long long)task->sched_info.run_delay,
2d72376b 361 task->sched_info.pcount);
1da177e4
LT		 362}
363#endif
364
9745512c
AV		 365#ifdef CONFIG_LATENCYTOP
366static int lstats_show_proc(struct seq_file *m, void *v)
367{
368 int i;
13d77c37
HS		 369 struct inode *inode = m->private;
370 struct task_struct *task = get_proc_task(inode);
9745512c 371
13d77c37
HS		 372 if (!task)
373 return -ESRCH;
374 seq_puts(m, "Latency Top version : v0.1\n");
9745512c
AV		 375 for (i = 0; i < 32; i++) {
376 if (task->latency_record[i].backtrace[0]) {
377 int q;
378 seq_printf(m, "%i %li %li ",
379 task->latency_record[i].count,
380 task->latency_record[i].time,
381 task->latency_record[i].max);
382 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
9c246247 383 char sym[KSYM_SYMBOL_LEN];
9745512c
AV		 384 char *c;
385 if (!task->latency_record[i].backtrace[q])
386 break;
387 if (task->latency_record[i].backtrace[q] == ULONG_MAX)
388 break;
389 sprint_symbol(sym, task->latency_record[i].backtrace[q]);
390 c = strchr(sym, '+');
391 if (c)
392 *c = 0;
393 seq_printf(m, "%s ", sym);
394 }
395 seq_printf(m, "\n");
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;
517
518 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
519 return sprintf(buffer, "running\n");
520
521 if (nr < 0)
522 return sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
523
524 return sprintf(buffer,
525 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
526 nr,
527 args[0], args[1], args[2], args[3], args[4], args[5],
528 sp, pc);
529}
530#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
531
1da177e4
LT		 532/************************************************************************/
533/* Here the fs part begins */
534/************************************************************************/
535
536/* permission checks */
778c1144 537static int proc_fd_access_allowed(struct inode *inode)
1da177e4 538{
778c1144
EB		 539 struct task_struct *task;
540 int allowed = 0;
df26c40e
EB		 541 /* Allow access to a task's file descriptors if it is us or we
542 * may use ptrace attach to the process and find out that
543 * information.
778c1144
EB		 544 */
545 task = get_proc_task(inode);
df26c40e 546 if (task) {
006ebb40 547 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
778c1144 548 put_task_struct(task);
df26c40e 549 }
778c1144 550 return allowed;
1da177e4
LT		 551}
552
6d76fa58
LT		 553static int proc_setattr(struct dentry *dentry, struct iattr *attr)
554{
555 int error;
556 struct inode *inode = dentry->d_inode;
557
558 if (attr->ia_valid & ATTR_MODE)
559 return -EPERM;
560
561 error = inode_change_ok(inode, attr);
1025774c
CH		 562 if (error)
563 return error;
564
565 if ((attr->ia_valid & ATTR_SIZE) &&
566 attr->ia_size != i_size_read(inode)) {
567 error = vmtruncate(inode, attr->ia_size);
568 if (error)
569 return error;
570 }
571
572 setattr_copy(inode, attr);
573 mark_inode_dirty(inode);
574 return 0;
6d76fa58
LT		 575}
576
c5ef1c42 577static const struct inode_operations proc_def_inode_operations = {
6d76fa58
LT		 578 .setattr = proc_setattr,
579};
580
a1a2c409
MS		 581static int mounts_open_common(struct inode *inode, struct file *file,
582 const struct seq_operations *op)
1da177e4 583{
99f89551 584 struct task_struct *task = get_proc_task(inode);
cf7b708c 585 struct nsproxy *nsp;
6b3286ed 586 struct mnt_namespace *ns = NULL;
a1a2c409 587 struct path root;
5addc5dd
AV		 588 struct proc_mounts *p;
589 int ret = -EINVAL;
1da177e4 590
99f89551 591 if (task) {
cf7b708c
PE		 592 rcu_read_lock();
593 nsp = task_nsproxy(task);
594 if (nsp) {
595 ns = nsp->mnt_ns;
863c4702
AD		 596 if (ns)
597 get_mnt_ns(ns);
598 }
cf7b708c 599 rcu_read_unlock();
f7ad3c6b 600 if (ns && get_task_root(task, &root) == 0)
7c2c7d99 601 ret = 0;
99f89551
EB		 602 put_task_struct(task);
603 }
5addc5dd 604
a1a2c409
MS		 605 if (!ns)
606 goto err;
7c2c7d99 607 if (ret)
a1a2c409
MS		 608 goto err_put_ns;
609
a1a2c409
MS		 610 ret = -ENOMEM;
611 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
612 if (!p)
613 goto err_put_path;
614
615 file->private_data = &p->m;
616 ret = seq_open(file, op);
617 if (ret)
618 goto err_free;
619
620 p->m.private = p;
621 p->ns = ns;
622 p->root = root;
623 p->event = ns->event;
624
625 return 0;
626
627 err_free:
628 kfree(p);
629 err_put_path:
630 path_put(&root);
631 err_put_ns:
632 put_mnt_ns(ns);
633 err:
1da177e4
LT		 634 return ret;
635}
636
637static int mounts_release(struct inode *inode, struct file *file)
638{
a1a2c409
MS		 639 struct proc_mounts *p = file->private_data;
640 path_put(&p->root);
641 put_mnt_ns(p->ns);
1da177e4
LT		 642 return seq_release(inode, file);
643}
644
5addc5dd
AV		 645static unsigned mounts_poll(struct file *file, poll_table *wait)
646{
647 struct proc_mounts *p = file->private_data;
31b07093 648 unsigned res = POLLIN | POLLRDNORM;
5addc5dd 649
9f5596af
AV		 650 poll_wait(file, &p->ns->poll, wait);
651 if (mnt_had_events(p))
31b07093 652 res |= POLLERR | POLLPRI;
5addc5dd
AV		 653
654 return res;
655}
656
a1a2c409
MS		 657static int mounts_open(struct inode *inode, struct file *file)
658{
659 return mounts_open_common(inode, file, &mounts_op);
660}
661
00977a59 662static const struct file_operations proc_mounts_operations = {
1da177e4
LT		 663 .open = mounts_open,
664 .read = seq_read,
665 .llseek = seq_lseek,
666 .release = mounts_release,
5addc5dd 667 .poll = mounts_poll,
1da177e4
LT		 668};
669
2d4d4864
RP		 670static int mountinfo_open(struct inode *inode, struct file *file)
671{
672 return mounts_open_common(inode, file, &mountinfo_op);
673}
674
675static const struct file_operations proc_mountinfo_operations = {
676 .open = mountinfo_open,
677 .read = seq_read,
678 .llseek = seq_lseek,
679 .release = mounts_release,
680 .poll = mounts_poll,
681};
682
b4629fe2
CL		 683static int mountstats_open(struct inode *inode, struct file *file)
684{
a1a2c409 685 return mounts_open_common(inode, file, &mountstats_op);
b4629fe2
CL		 686}
687
00977a59 688static const struct file_operations proc_mountstats_operations = {
b4629fe2
CL		 689 .open = mountstats_open,
690 .read = seq_read,
691 .llseek = seq_lseek,
692 .release = mounts_release,
693};
694
1da177e4
LT		 695#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
696
697static ssize_t proc_info_read(struct file * file, char __user * buf,
698 size_t count, loff_t *ppos)
699{
2fddfeef 700 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 701 unsigned long page;
702 ssize_t length;
99f89551
EB		 703 struct task_struct *task = get_proc_task(inode);
704
705 length = -ESRCH;
706 if (!task)
707 goto out_no_task;
1da177e4
LT		 708
709 if (count > PROC_BLOCK_SIZE)
710 count = PROC_BLOCK_SIZE;
99f89551
EB		 711
712 length = -ENOMEM;
e12ba74d 713 if (!(page = __get_free_page(GFP_TEMPORARY)))
99f89551 714 goto out;
1da177e4
LT		 715
716 length = PROC_I(inode)->op.proc_read(task, (char*)page);
717
718 if (length >= 0)
719 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
720 free_page(page);
99f89551
EB		 721out:
722 put_task_struct(task);
723out_no_task:
1da177e4
LT		 724 return length;
725}
726
00977a59 727static const struct file_operations proc_info_file_operations = {
1da177e4 728 .read = proc_info_read,
87df8424 729 .llseek = generic_file_llseek,
1da177e4
LT		 730};
731
be614086
EB		 732static int proc_single_show(struct seq_file *m, void *v)
733{
734 struct inode *inode = m->private;
735 struct pid_namespace *ns;
736 struct pid *pid;
737 struct task_struct *task;
738 int ret;
739
740 ns = inode->i_sb->s_fs_info;
741 pid = proc_pid(inode);
742 task = get_pid_task(pid, PIDTYPE_PID);
743 if (!task)
744 return -ESRCH;
745
746 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
747
748 put_task_struct(task);
749 return ret;
750}
751
752static int proc_single_open(struct inode *inode, struct file *filp)
753{
754 int ret;
755 ret = single_open(filp, proc_single_show, NULL);
756 if (!ret) {
757 struct seq_file *m = filp->private_data;
758
759 m->private = inode;
760 }
761 return ret;
762}
763
764static const struct file_operations proc_single_file_operations = {
765 .open = proc_single_open,
766 .read = seq_read,
767 .llseek = seq_lseek,
768 .release = single_release,
769};
770
1da177e4
LT		 771static int mem_open(struct inode* inode, struct file* file)
772{
773 file->private_data = (void*)((long)current->self_exec_id);
4a3956c7
KH		 774 /* OK to pass negative loff_t, we can catch out-of-range */
775 file->f_mode |= FMODE_UNSIGNED_OFFSET;
1da177e4
LT		 776 return 0;
777}
778
779static ssize_t mem_read(struct file * file, char __user * buf,
780 size_t count, loff_t *ppos)
781{
2fddfeef 782 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1da177e4
LT		 783 char *page;
784 unsigned long src = *ppos;
785 int ret = -ESRCH;
786 struct mm_struct *mm;
787
99f89551
EB		 788 if (!task)
789 goto out_no_task;
790
638fa202 791 if (check_mem_permission(task))
1da177e4
LT		 792 goto out;
793
794 ret = -ENOMEM;
e12ba74d 795 page = (char *)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 796 if (!page)
797 goto out;
798
799 ret = 0;
800
801 mm = get_task_mm(task);
802 if (!mm)
803 goto out_free;
804
805 ret = -EIO;
806
807 if (file->private_data != (void*)((long)current->self_exec_id))
808 goto out_put;
809
810 ret = 0;
811
812 while (count > 0) {
813 int this_len, retval;
814
815 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
816 retval = access_process_vm(task, src, page, this_len, 0);
638fa202 817 if (!retval || check_mem_permission(task)) {
1da177e4
LT		 818 if (!ret)
819 ret = -EIO;
820 break;
821 }
822
823 if (copy_to_user(buf, page, retval)) {
824 ret = -EFAULT;
825 break;
826 }
827
828 ret += retval;
829 src += retval;
830 buf += retval;
831 count -= retval;
832 }
833 *ppos = src;
834
835out_put:
836 mmput(mm);
837out_free:
838 free_page((unsigned long) page);
839out:
99f89551
EB		 840 put_task_struct(task);
841out_no_task:
1da177e4
LT		 842 return ret;
843}
844
845#define mem_write NULL
846
847#ifndef mem_write
848/* This is a security hazard */
63967fa9 849static ssize_t mem_write(struct file * file, const char __user *buf,
1da177e4
LT		 850 size_t count, loff_t *ppos)
851{
f7ca54f4 852 int copied;
1da177e4 853 char *page;
2fddfeef 854 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1da177e4
LT		 855 unsigned long dst = *ppos;
856
99f89551
EB		 857 copied = -ESRCH;
858 if (!task)
859 goto out_no_task;
860
638fa202 861 if (check_mem_permission(task))
99f89551 862 goto out;
1da177e4 863
99f89551 864 copied = -ENOMEM;
e12ba74d 865 page = (char *)__get_free_page(GFP_TEMPORARY);
1da177e4 866 if (!page)
99f89551 867 goto out;
1da177e4 868
f7ca54f4 869 copied = 0;
1da177e4
LT		 870 while (count > 0) {
871 int this_len, retval;
872
873 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
874 if (copy_from_user(page, buf, this_len)) {
875 copied = -EFAULT;
876 break;
877 }
878 retval = access_process_vm(task, dst, page, this_len, 1);
879 if (!retval) {
880 if (!copied)
881 copied = -EIO;
882 break;
883 }
884 copied += retval;
885 buf += retval;
886 dst += retval;
887 count -= retval;
888 }
889 *ppos = dst;
890 free_page((unsigned long) page);
99f89551
EB		 891out:
892 put_task_struct(task);
893out_no_task:
1da177e4
LT		 894 return copied;
895}
896#endif
897
85863e47 898loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 899{
900 switch (orig) {
901 case 0:
902 file->f_pos = offset;
903 break;
904 case 1:
905 file->f_pos += offset;
906 break;
907 default:
908 return -EINVAL;
909 }
910 force_successful_syscall_return();
911 return file->f_pos;
912}
913
00977a59 914static const struct file_operations proc_mem_operations = {
1da177e4
LT		 915 .llseek = mem_lseek,
916 .read = mem_read,
917 .write = mem_write,
918 .open = mem_open,
919};
920
315e28c8
JP		 921static ssize_t environ_read(struct file *file, char __user *buf,
922 size_t count, loff_t *ppos)
923{
924 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
925 char *page;
926 unsigned long src = *ppos;
927 int ret = -ESRCH;
928 struct mm_struct *mm;
929
930 if (!task)
931 goto out_no_task;
932
006ebb40 933 if (!ptrace_may_access(task, PTRACE_MODE_READ))
315e28c8
JP		 934 goto out;
935
936 ret = -ENOMEM;
937 page = (char *)__get_free_page(GFP_TEMPORARY);
938 if (!page)
939 goto out;
940
941 ret = 0;
942
943 mm = get_task_mm(task);
944 if (!mm)
945 goto out_free;
946
947 while (count > 0) {
948 int this_len, retval, max_len;
949
950 this_len = mm->env_end - (mm->env_start + src);
951
952 if (this_len <= 0)
953 break;
954
955 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
956 this_len = (this_len > max_len) ? max_len : this_len;
957
958 retval = access_process_vm(task, (mm->env_start + src),
959 page, this_len, 0);
960
961 if (retval <= 0) {
962 ret = retval;
963 break;
964 }
965
966 if (copy_to_user(buf, page, retval)) {
967 ret = -EFAULT;
968 break;
969 }
970
971 ret += retval;
972 src += retval;
973 buf += retval;
974 count -= retval;
975 }
976 *ppos = src;
977
978 mmput(mm);
979out_free:
980 free_page((unsigned long) page);
981out:
982 put_task_struct(task);
983out_no_task:
984 return ret;
985}
986
987static const struct file_operations proc_environ_operations = {
988 .read = environ_read,
87df8424 989 .llseek = generic_file_llseek,
315e28c8
JP		 990};
991
1da177e4
LT		 992static ssize_t oom_adjust_read(struct file *file, char __user *buf,
993 size_t count, loff_t *ppos)
994{
2fddfeef 995 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
8578cea7 996 char buffer[PROC_NUMBUF];
1da177e4 997 size_t len;
28b83c51
KM		 998 int oom_adjust = OOM_DISABLE;
999 unsigned long flags;
1da177e4 1000
99f89551
EB		 1001 if (!task)
1002 return -ESRCH;
28b83c51
KM		 1003
1004 if (lock_task_sighand(task, &flags)) {
1005 oom_adjust = task->signal->oom_adj;
1006 unlock_task_sighand(task, &flags);
1007 }
1008
99f89551
EB		 1009 put_task_struct(task);
1010
8578cea7 1011 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
0c28f287
AM		 1012
1013 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1da177e4
LT		 1014}
1015
1016static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
1017 size_t count, loff_t *ppos)
1018{
99f89551 1019 struct task_struct *task;
5d863b89
KM		 1020 char buffer[PROC_NUMBUF];
1021 long oom_adjust;
28b83c51 1022 unsigned long flags;
5d863b89 1023 int err;
1da177e4 1024
8578cea7
EB		 1025 memset(buffer, 0, sizeof(buffer));
1026 if (count > sizeof(buffer) - 1)
1027 count = sizeof(buffer) - 1;
723548bf
DR		 1028 if (copy_from_user(buffer, buf, count)) {
1029 err = -EFAULT;
1030 goto out;
1031 }
5d863b89
KM		 1032
1033 err = strict_strtol(strstrip(buffer), 0, &oom_adjust);
1034 if (err)
723548bf 1035 goto out;
8ac773b4 1036 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
723548bf
DR		 1037 oom_adjust != OOM_DISABLE) {
1038 err = -EINVAL;
1039 goto out;
1040 }
5d863b89 1041
2fddfeef 1042 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 1043 if (!task) {
1044 err = -ESRCH;
1045 goto out;
1046 }
d19d5476
DR		 1047
1048 task_lock(task);
1049 if (!task->mm) {
1050 err = -EINVAL;
1051 goto err_task_lock;
1052 }
1053
28b83c51 1054 if (!lock_task_sighand(task, &flags)) {
723548bf 1055 err = -ESRCH;
d19d5476 1056 goto err_task_lock;
28b83c51
KM		 1057 }
1058
1059 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 1060 err = -EACCES;
1061 goto err_sighand;
8fb4fc68 1062 }
28b83c51 1063
3d5992d2
YH		 1064 if (oom_adjust != task->signal->oom_adj) {
1065 if (oom_adjust == OOM_DISABLE)
1066 atomic_inc(&task->mm->oom_disable_count);
1067 if (task->signal->oom_adj == OOM_DISABLE)
1068 atomic_dec(&task->mm->oom_disable_count);
1069 }
1070
51b1bd2a
DR		 1071 /*
1072 * Warn that /proc/pid/oom_adj is deprecated, see
1073 * Documentation/feature-removal-schedule.txt.
1074 */
1075 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, "
1076 "please use /proc/%d/oom_score_adj instead.\n",
1077 current->comm, task_pid_nr(current),
1078 task_pid_nr(task), task_pid_nr(task));
28b83c51 1079 task->signal->oom_adj = oom_adjust;
a63d83f4
DR		 1080 /*
1081 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1082 * value is always attainable.
1083 */
1084 if (task->signal->oom_adj == OOM_ADJUST_MAX)
1085 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
1086 else
1087 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
1088 -OOM_DISABLE;
723548bf 1089err_sighand:
28b83c51 1090 unlock_task_sighand(task, &flags);
d19d5476
DR		 1091err_task_lock:
1092 task_unlock(task);
99f89551 1093 put_task_struct(task);
723548bf
DR		 1094out:
1095 return err < 0 ? err : count;
1da177e4
LT		 1096}
1097
00977a59 1098static const struct file_operations proc_oom_adjust_operations = {
1da177e4
LT		 1099 .read = oom_adjust_read,
1100 .write = oom_adjust_write,
87df8424 1101 .llseek = generic_file_llseek,
1da177e4
LT		 1102};
1103
a63d83f4
DR		 1104static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1105 size_t count, loff_t *ppos)
1106{
1107 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1108 char buffer[PROC_NUMBUF];
1109 int oom_score_adj = OOM_SCORE_ADJ_MIN;
1110 unsigned long flags;
1111 size_t len;
1112
1113 if (!task)
1114 return -ESRCH;
1115 if (lock_task_sighand(task, &flags)) {
1116 oom_score_adj = task->signal->oom_score_adj;
1117 unlock_task_sighand(task, &flags);
1118 }
1119 put_task_struct(task);
1120 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
1121 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1122}
1123
1124static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1125 size_t count, loff_t *ppos)
1126{
1127 struct task_struct *task;
1128 char buffer[PROC_NUMBUF];
1129 unsigned long flags;
1130 long oom_score_adj;
1131 int err;
1132
1133 memset(buffer, 0, sizeof(buffer));
1134 if (count > sizeof(buffer) - 1)
1135 count = sizeof(buffer) - 1;
723548bf
DR		 1136 if (copy_from_user(buffer, buf, count)) {
1137 err = -EFAULT;
1138 goto out;
1139 }
a63d83f4
DR		 1140
1141 err = strict_strtol(strstrip(buffer), 0, &oom_score_adj);
1142 if (err)
723548bf 1143 goto out;
a63d83f4 1144 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
723548bf
DR		 1145 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1146 err = -EINVAL;
1147 goto out;
1148 }
a63d83f4
DR		 1149
1150 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 1151 if (!task) {
1152 err = -ESRCH;
1153 goto out;
1154 }
d19d5476
DR		 1155
1156 task_lock(task);
1157 if (!task->mm) {
1158 err = -EINVAL;
1159 goto err_task_lock;
1160 }
1161
a63d83f4 1162 if (!lock_task_sighand(task, &flags)) {
723548bf 1163 err = -ESRCH;
d19d5476 1164 goto err_task_lock;
a63d83f4 1165 }
d19d5476 1166
a63d83f4
DR		 1167 if (oom_score_adj < task->signal->oom_score_adj &&
1168 !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 1169 err = -EACCES;
1170 goto err_sighand;
a63d83f4
DR		 1171 }
1172
3d5992d2
YH		 1173 if (oom_score_adj != task->signal->oom_score_adj) {
1174 if (oom_score_adj == OOM_SCORE_ADJ_MIN)
1175 atomic_inc(&task->mm->oom_disable_count);
1176 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1177 atomic_dec(&task->mm->oom_disable_count);
1178 }
a63d83f4
DR		 1179 task->signal->oom_score_adj = oom_score_adj;
1180 /*
1181 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1182 * always attainable.
1183 */
1184 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1185 task->signal->oom_adj = OOM_DISABLE;
1186 else
1187 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1188 OOM_SCORE_ADJ_MAX;
723548bf 1189err_sighand:
a63d83f4 1190 unlock_task_sighand(task, &flags);
d19d5476
DR		 1191err_task_lock:
1192 task_unlock(task);
a63d83f4 1193 put_task_struct(task);
723548bf
DR		 1194out:
1195 return err < 0 ? err : count;
a63d83f4
DR		 1196}
1197
1198static const struct file_operations proc_oom_score_adj_operations = {
1199 .read = oom_score_adj_read,
1200 .write = oom_score_adj_write,
6038f373 1201 .llseek = default_llseek,
a63d83f4
DR		 1202};
1203
1da177e4
LT		 1204#ifdef CONFIG_AUDITSYSCALL
1205#define TMPBUFLEN 21
1206static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1207 size_t count, loff_t *ppos)
1208{
2fddfeef 1209 struct inode * inode = file->f_path.dentry->d_inode;
99f89551 1210 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1211 ssize_t length;
1212 char tmpbuf[TMPBUFLEN];
1213
99f89551
EB		 1214 if (!task)
1215 return -ESRCH;
1da177e4 1216 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
0c11b942 1217 audit_get_loginuid(task));
99f89551 1218 put_task_struct(task);
1da177e4
LT		 1219 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1220}
1221
1222static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1223 size_t count, loff_t *ppos)
1224{
2fddfeef 1225 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1226 char *page, *tmp;
1227 ssize_t length;
1da177e4
LT		 1228 uid_t loginuid;
1229
1230 if (!capable(CAP_AUDIT_CONTROL))
1231 return -EPERM;
1232
7dc52157
PM		 1233 rcu_read_lock();
1234 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1235 rcu_read_unlock();
1da177e4 1236 return -EPERM;
7dc52157
PM		 1237 }
1238 rcu_read_unlock();
1da177e4 1239
e0182909
AV		 1240 if (count >= PAGE_SIZE)
1241 count = PAGE_SIZE - 1;
1da177e4
LT		 1242
1243 if (*ppos != 0) {
1244 /* No partial writes. */
1245 return -EINVAL;
1246 }
e12ba74d 1247 page = (char*)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 1248 if (!page)
1249 return -ENOMEM;
1250 length = -EFAULT;
1251 if (copy_from_user(page, buf, count))
1252 goto out_free_page;
1253
e0182909 1254 page[count] = '\0';
1da177e4
LT		 1255 loginuid = simple_strtoul(page, &tmp, 10);
1256 if (tmp == page) {
1257 length = -EINVAL;
1258 goto out_free_page;
1259
1260 }
99f89551 1261 length = audit_set_loginuid(current, loginuid);
1da177e4
LT		 1262 if (likely(length == 0))
1263 length = count;
1264
1265out_free_page:
1266 free_page((unsigned long) page);
1267 return length;
1268}
1269
00977a59 1270static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1271 .read = proc_loginuid_read,
1272 .write = proc_loginuid_write,
87df8424 1273 .llseek = generic_file_llseek,
1da177e4 1274};
1e0bd755
EP		 1275
1276static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1277 size_t count, loff_t *ppos)
1278{
1279 struct inode * inode = file->f_path.dentry->d_inode;
1280 struct task_struct *task = get_proc_task(inode);
1281 ssize_t length;
1282 char tmpbuf[TMPBUFLEN];
1283
1284 if (!task)
1285 return -ESRCH;
1286 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1287 audit_get_sessionid(task));
1288 put_task_struct(task);
1289 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1290}
1291
1292static const struct file_operations proc_sessionid_operations = {
1293 .read = proc_sessionid_read,
87df8424 1294 .llseek = generic_file_llseek,
1e0bd755 1295};
1da177e4
LT		 1296#endif
1297
f4f154fd
AM		 1298#ifdef CONFIG_FAULT_INJECTION
1299static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1300 size_t count, loff_t *ppos)
1301{
1302 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1303 char buffer[PROC_NUMBUF];
1304 size_t len;
1305 int make_it_fail;
f4f154fd
AM		 1306
1307 if (!task)
1308 return -ESRCH;
1309 make_it_fail = task->make_it_fail;
1310 put_task_struct(task);
1311
1312 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1313
1314 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1315}
1316
1317static ssize_t proc_fault_inject_write(struct file * file,
1318 const char __user * buf, size_t count, loff_t *ppos)
1319{
1320 struct task_struct *task;
1321 char buffer[PROC_NUMBUF], *end;
1322 int make_it_fail;
1323
1324 if (!capable(CAP_SYS_RESOURCE))
1325 return -EPERM;
1326 memset(buffer, 0, sizeof(buffer));
1327 if (count > sizeof(buffer) - 1)
1328 count = sizeof(buffer) - 1;
1329 if (copy_from_user(buffer, buf, count))
1330 return -EFAULT;
cba8aafe
VL		 1331 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1332 if (*end)
1333 return -EINVAL;
f4f154fd
AM		 1334 task = get_proc_task(file->f_dentry->d_inode);
1335 if (!task)
1336 return -ESRCH;
1337 task->make_it_fail = make_it_fail;
1338 put_task_struct(task);
cba8aafe
VL		 1339
1340 return count;
f4f154fd
AM		 1341}
1342
00977a59 1343static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1344 .read = proc_fault_inject_read,
1345 .write = proc_fault_inject_write,
87df8424 1346 .llseek = generic_file_llseek,
f4f154fd
AM		 1347};
1348#endif
1349
9745512c 1350
43ae34cb
IM		 1351#ifdef CONFIG_SCHED_DEBUG
1352/*
1353 * Print out various scheduling related per-task fields:
1354 */
1355static int sched_show(struct seq_file *m, void *v)
1356{
1357 struct inode *inode = m->private;
1358 struct task_struct *p;
1359
43ae34cb
IM		 1360 p = get_proc_task(inode);
1361 if (!p)
1362 return -ESRCH;
1363 proc_sched_show_task(p, m);
1364
1365 put_task_struct(p);
1366
1367 return 0;
1368}
1369
1370static ssize_t
1371sched_write(struct file *file, const char __user *buf,
1372 size_t count, loff_t *offset)
1373{
1374 struct inode *inode = file->f_path.dentry->d_inode;
1375 struct task_struct *p;
1376
43ae34cb
IM		 1377 p = get_proc_task(inode);
1378 if (!p)
1379 return -ESRCH;
1380 proc_sched_set_task(p);
1381
1382 put_task_struct(p);
1383
1384 return count;
1385}
1386
1387static int sched_open(struct inode *inode, struct file *filp)
1388{
1389 int ret;
1390
1391 ret = single_open(filp, sched_show, NULL);
1392 if (!ret) {
1393 struct seq_file *m = filp->private_data;
1394
1395 m->private = inode;
1396 }
1397 return ret;
1398}
1399
1400static const struct file_operations proc_pid_sched_operations = {
1401 .open = sched_open,
1402 .read = seq_read,
1403 .write = sched_write,
1404 .llseek = seq_lseek,
5ea473a1 1405 .release = single_release,
43ae34cb
IM		 1406};
1407
1408#endif
1409
5091faa4
MG		 1410#ifdef CONFIG_SCHED_AUTOGROUP
1411/*
1412 * Print out autogroup related information:
1413 */
1414static int sched_autogroup_show(struct seq_file *m, void *v)
1415{
1416 struct inode *inode = m->private;
1417 struct task_struct *p;
1418
1419 p = get_proc_task(inode);
1420 if (!p)
1421 return -ESRCH;
1422 proc_sched_autogroup_show_task(p, m);
1423
1424 put_task_struct(p);
1425
1426 return 0;
1427}
1428
1429static ssize_t
1430sched_autogroup_write(struct file *file, const char __user *buf,
1431 size_t count, loff_t *offset)
1432{
1433 struct inode *inode = file->f_path.dentry->d_inode;
1434 struct task_struct *p;
1435 char buffer[PROC_NUMBUF];
1436 long nice;
1437 int err;
1438
1439 memset(buffer, 0, sizeof(buffer));
1440 if (count > sizeof(buffer) - 1)
1441 count = sizeof(buffer) - 1;
1442 if (copy_from_user(buffer, buf, count))
1443 return -EFAULT;
1444
1445 err = strict_strtol(strstrip(buffer), 0, &nice);
1446 if (err)
1447 return -EINVAL;
1448
1449 p = get_proc_task(inode);
1450 if (!p)
1451 return -ESRCH;
1452
1453 err = nice;
1454 err = proc_sched_autogroup_set_nice(p, &err);
1455 if (err)
1456 count = err;
1457
1458 put_task_struct(p);
1459
1460 return count;
1461}
1462
1463static int sched_autogroup_open(struct inode *inode, struct file *filp)
1464{
1465 int ret;
1466
1467 ret = single_open(filp, sched_autogroup_show, NULL);
1468 if (!ret) {
1469 struct seq_file *m = filp->private_data;
1470
1471 m->private = inode;
1472 }
1473 return ret;
1474}
1475
1476static const struct file_operations proc_pid_sched_autogroup_operations = {
1477 .open = sched_autogroup_open,
1478 .read = seq_read,
1479 .write = sched_autogroup_write,
1480 .llseek = seq_lseek,
1481 .release = single_release,
1482};
1483
1484#endif /* CONFIG_SCHED_AUTOGROUP */
1485
4614a696
JS		 1486static ssize_t comm_write(struct file *file, const char __user *buf,
1487 size_t count, loff_t *offset)
1488{
1489 struct inode *inode = file->f_path.dentry->d_inode;
1490 struct task_struct *p;
1491 char buffer[TASK_COMM_LEN];
1492
1493 memset(buffer, 0, sizeof(buffer));
1494 if (count > sizeof(buffer) - 1)
1495 count = sizeof(buffer) - 1;
1496 if (copy_from_user(buffer, buf, count))
1497 return -EFAULT;
1498
1499 p = get_proc_task(inode);
1500 if (!p)
1501 return -ESRCH;
1502
1503 if (same_thread_group(current, p))
1504 set_task_comm(p, buffer);
1505 else
1506 count = -EINVAL;
1507
1508 put_task_struct(p);
1509
1510 return count;
1511}
1512
1513static int comm_show(struct seq_file *m, void *v)
1514{
1515 struct inode *inode = m->private;
1516 struct task_struct *p;
1517
1518 p = get_proc_task(inode);
1519 if (!p)
1520 return -ESRCH;
1521
1522 task_lock(p);
1523 seq_printf(m, "%s\n", p->comm);
1524 task_unlock(p);
1525
1526 put_task_struct(p);
1527
1528 return 0;
1529}
1530
1531static int comm_open(struct inode *inode, struct file *filp)
1532{
1533 int ret;
1534
1535 ret = single_open(filp, comm_show, NULL);
1536 if (!ret) {
1537 struct seq_file *m = filp->private_data;
1538
1539 m->private = inode;
1540 }
1541 return ret;
1542}
1543
1544static const struct file_operations proc_pid_set_comm_operations = {
1545 .open = comm_open,
1546 .read = seq_read,
1547 .write = comm_write,
1548 .llseek = seq_lseek,
1549 .release = single_release,
1550};
1551
925d1c40
MH		 1552/*
1553 * We added or removed a vma mapping the executable. The vmas are only mapped
1554 * during exec and are not mapped with the mmap system call.
1555 * Callers must hold down_write() on the mm's mmap_sem for these
1556 */
1557void added_exe_file_vma(struct mm_struct *mm)
1558{
1559 mm->num_exe_file_vmas++;
1560}
1561
1562void removed_exe_file_vma(struct mm_struct *mm)
1563{
1564 mm->num_exe_file_vmas--;
1565 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){
1566 fput(mm->exe_file);
1567 mm->exe_file = NULL;
1568 }
1569
1570}
1571
1572void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file)
1573{
1574 if (new_exe_file)
1575 get_file(new_exe_file);
1576 if (mm->exe_file)
1577 fput(mm->exe_file);
1578 mm->exe_file = new_exe_file;
1579 mm->num_exe_file_vmas = 0;
1580}
1581
1582struct file *get_mm_exe_file(struct mm_struct *mm)
1583{
1584 struct file *exe_file;
1585
1586 /* We need mmap_sem to protect against races with removal of
1587 * VM_EXECUTABLE vmas */
1588 down_read(&mm->mmap_sem);
1589 exe_file = mm->exe_file;
1590 if (exe_file)
1591 get_file(exe_file);
1592 up_read(&mm->mmap_sem);
1593 return exe_file;
1594}
1595
1596void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm)
1597{
1598 /* It's safe to write the exe_file pointer without exe_file_lock because
1599 * this is called during fork when the task is not yet in /proc */
1600 newmm->exe_file = get_mm_exe_file(oldmm);
1601}
1602
1603static int proc_exe_link(struct inode *inode, struct path *exe_path)
1604{
1605 struct task_struct *task;
1606 struct mm_struct *mm;
1607 struct file *exe_file;
1608
1609 task = get_proc_task(inode);
1610 if (!task)
1611 return -ENOENT;
1612 mm = get_task_mm(task);
1613 put_task_struct(task);
1614 if (!mm)
1615 return -ENOENT;
1616 exe_file = get_mm_exe_file(mm);
1617 mmput(mm);
1618 if (exe_file) {
1619 *exe_path = exe_file->f_path;
1620 path_get(&exe_file->f_path);
1621 fput(exe_file);
1622 return 0;
1623 } else
1624 return -ENOENT;
1625}
1626
008b150a 1627static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1628{
1629 struct inode *inode = dentry->d_inode;
1630 int error = -EACCES;
1631
1632 /* We don't need a base pointer in the /proc filesystem */
1d957f9b 1633 path_put(&nd->path);
1da177e4 1634
778c1144
EB		 1635 /* Are we allowed to snoop on the tasks file descriptors? */
1636 if (!proc_fd_access_allowed(inode))
1da177e4 1637 goto out;
1da177e4 1638
3dcd25f3 1639 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
1da177e4 1640out:
008b150a 1641 return ERR_PTR(error);
1da177e4
LT		 1642}
1643
3dcd25f3 1644static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1645{
e12ba74d 1646 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1647 char *pathname;
1da177e4
LT		 1648 int len;
1649
1650 if (!tmp)
1651 return -ENOMEM;
0c28f287 1652
7b2a69ba 1653 pathname = d_path(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1654 len = PTR_ERR(pathname);
1655 if (IS_ERR(pathname))
1da177e4 1656 goto out;
3dcd25f3 1657 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1658
1659 if (len > buflen)
1660 len = buflen;
3dcd25f3 1661 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1662 len = -EFAULT;
1663 out:
1664 free_page((unsigned long)tmp);
1665 return len;
1666}
1667
1668static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1669{
1670 int error = -EACCES;
1671 struct inode *inode = dentry->d_inode;
3dcd25f3 1672 struct path path;
1da177e4 1673
778c1144
EB		 1674 /* Are we allowed to snoop on the tasks file descriptors? */
1675 if (!proc_fd_access_allowed(inode))
1da177e4 1676 goto out;
1da177e4 1677
3dcd25f3 1678 error = PROC_I(inode)->op.proc_get_link(inode, &path);
1da177e4
LT		 1679 if (error)
1680 goto out;
1681
3dcd25f3
JB		 1682 error = do_proc_readlink(&path, buffer, buflen);
1683 path_put(&path);
1da177e4 1684out:
1da177e4
LT		 1685 return error;
1686}
1687
c5ef1c42 1688static const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1689 .readlink = proc_pid_readlink,
6d76fa58
LT		 1690 .follow_link = proc_pid_follow_link,
1691 .setattr = proc_setattr,
1da177e4
LT		 1692};
1693
28a6d671
EB		 1694
1695/* building an inode */
1696
1697static int task_dumpable(struct task_struct *task)
1da177e4 1698{
28a6d671
EB		 1699 int dumpable = 0;
1700 struct mm_struct *mm;
1da177e4 1701
28a6d671
EB		 1702 task_lock(task);
1703 mm = task->mm;
1704 if (mm)
6c5d5238 1705 dumpable = get_dumpable(mm);
28a6d671
EB		 1706 task_unlock(task);
1707 if(dumpable == 1)
1708 return 1;
1709 return 0;
1710}
1da177e4 1711
1da177e4 1712
61a28784 1713static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1714{
1715 struct inode * inode;
1716 struct proc_inode *ei;
c69e8d9c 1717 const struct cred *cred;
1da177e4 1718
28a6d671 1719 /* We need a new inode */
1da177e4 1720
28a6d671
EB		 1721 inode = new_inode(sb);
1722 if (!inode)
1723 goto out;
1724
1725 /* Common stuff */
1726 ei = PROC_I(inode);
85fe4025 1727 inode->i_ino = get_next_ino();
28a6d671 1728 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
28a6d671
EB		 1729 inode->i_op = &proc_def_inode_operations;
1730
1731 /*
1732 * grab the reference to task.
1733 */
1a657f78 1734 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1735 if (!ei->pid)
1736 goto out_unlock;
1737
28a6d671 1738 if (task_dumpable(task)) {
c69e8d9c
DH		 1739 rcu_read_lock();
1740 cred = __task_cred(task);
1741 inode->i_uid = cred->euid;
1742 inode->i_gid = cred->egid;
1743 rcu_read_unlock();
1da177e4 1744 }
28a6d671
EB		 1745 security_task_to_inode(task, inode);
1746
1da177e4 1747out:
28a6d671
EB		 1748 return inode;
1749
1750out_unlock:
1751 iput(inode);
1752 return NULL;
1da177e4
LT		 1753}
1754
28a6d671 1755static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1756{
1da177e4 1757 struct inode *inode = dentry->d_inode;
28a6d671 1758 struct task_struct *task;
c69e8d9c
DH		 1759 const struct cred *cred;
1760
28a6d671 1761 generic_fillattr(inode, stat);
1da177e4 1762
28a6d671
EB		 1763 rcu_read_lock();
1764 stat->uid = 0;
1765 stat->gid = 0;
1766 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1767 if (task) {
1768 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1769 task_dumpable(task)) {
c69e8d9c
DH		 1770 cred = __task_cred(task);
1771 stat->uid = cred->euid;
1772 stat->gid = cred->egid;
1da177e4
LT		 1773 }
1774 }
28a6d671 1775 rcu_read_unlock();
d6e71144 1776 return 0;
1da177e4
LT		 1777}
1778
1da177e4
LT		 1779/* dentry stuff */
1780
1781/*
1782 * Exceptional case: normally we are not allowed to unhash a busy
1783 * directory. In this case, however, we can do it - no aliasing problems
1784 * due to the way we treat inodes.
1785 *
1786 * Rewrite the inode's ownerships here because the owning task may have
1787 * performed a setuid(), etc.
99f89551
EB		 1788 *
1789 * Before the /proc/pid/status file was created the only way to read
1790 * the effective uid of a /process was to stat /proc/pid. Reading
1791 * /proc/pid/status is slow enough that procps and other packages
1792 * kept stating /proc/pid. To keep the rules in /proc simple I have
1793 * made this apply to all per process world readable and executable
1794 * directories.
1da177e4
LT		 1795 */
1796static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1797{
34286d66
NP		 1798 struct inode *inode;
1799 struct task_struct *task;
c69e8d9c
DH		 1800 const struct cred *cred;
1801
34286d66
NP		 1802 if (nd && nd->flags & LOOKUP_RCU)
1803 return -ECHILD;
1804
1805 inode = dentry->d_inode;
1806 task = get_proc_task(inode);
1807
99f89551
EB		 1808 if (task) {
1809 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1810 task_dumpable(task)) {
c69e8d9c
DH		 1811 rcu_read_lock();
1812 cred = __task_cred(task);
1813 inode->i_uid = cred->euid;
1814 inode->i_gid = cred->egid;
1815 rcu_read_unlock();
1da177e4
LT		 1816 } else {
1817 inode->i_uid = 0;
1818 inode->i_gid = 0;
1819 }
9ee8ab9f 1820 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1821 security_task_to_inode(task, inode);
99f89551 1822 put_task_struct(task);
1da177e4
LT		 1823 return 1;
1824 }
1825 d_drop(dentry);
1826 return 0;
1827}
1828
fe15ce44 1829static int pid_delete_dentry(const struct dentry * dentry)
99f89551 1830{
28a6d671
EB		 1831 /* Is the task we represent dead?
1832 * If so, then don't put the dentry on the lru list,
1833 * kill it immediately.
1834 */
1835 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1836}
1837
d72f71eb 1838static const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1839{
1840 .d_revalidate = pid_revalidate,
1841 .d_delete = pid_delete_dentry,
1842};
1843
1844/* Lookups */
1845
c5141e6d
ED		 1846typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
1847 struct task_struct *, const void *);
61a28784 1848
1c0d04c9
EB		 1849/*
1850 * Fill a directory entry.
1851 *
1852 * If possible create the dcache entry and derive our inode number and
1853 * file type from dcache entry.
1854 *
1855 * Since all of the proc inode numbers are dynamically generated, the inode
1856 * numbers do not exist until the inode is cache. This means creating the
1857 * the dcache entry in readdir is necessary to keep the inode numbers
1858 * reported by readdir in sync with the inode numbers reported
1859 * by stat.
1860 */
61a28784
EB		 1861static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1862 char *name, int len,
c5141e6d 1863 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1864{
2fddfeef 1865 struct dentry *child, *dir = filp->f_path.dentry;
61a28784
EB		 1866 struct inode *inode;
1867 struct qstr qname;
1868 ino_t ino = 0;
1869 unsigned type = DT_UNKNOWN;
1870
1871 qname.name = name;
1872 qname.len = len;
1873 qname.hash = full_name_hash(name, len);
1874
1875 child = d_lookup(dir, &qname);
1876 if (!child) {
1877 struct dentry *new;
1878 new = d_alloc(dir, &qname);
1879 if (new) {
1880 child = instantiate(dir->d_inode, new, task, ptr);
1881 if (child)
1882 dput(new);
1883 else
1884 child = new;
1885 }
1886 }
1887 if (!child || IS_ERR(child) || !child->d_inode)
1888 goto end_instantiate;
1889 inode = child->d_inode;
1890 if (inode) {
1891 ino = inode->i_ino;
1892 type = inode->i_mode >> 12;
1893 }
1894 dput(child);
1895end_instantiate:
1896 if (!ino)
1897 ino = find_inode_number(dir, &qname);
1898 if (!ino)
1899 ino = 1;
1900 return filldir(dirent, name, len, filp->f_pos, ino, type);
1901}
1902
28a6d671
EB		 1903static unsigned name_to_int(struct dentry *dentry)
1904{
1905 const char *name = dentry->d_name.name;
1906 int len = dentry->d_name.len;
1907 unsigned n = 0;
1908
1909 if (len > 1 && *name == '0')
1910 goto out;
1911 while (len-- > 0) {
1912 unsigned c = *name++ - '0';
1913 if (c > 9)
1914 goto out;
1915 if (n >= (~0U-9)/10)
1916 goto out;
1917 n *= 10;
1918 n += c;
1919 }
1920 return n;
1921out:
1922 return ~0U;
1923}
1924
27932742
MS		 1925#define PROC_FDINFO_MAX 64
1926
3dcd25f3 1927static int proc_fd_info(struct inode *inode, struct path *path, char *info)
28a6d671
EB		 1928{
1929 struct task_struct *task = get_proc_task(inode);
1930 struct files_struct *files = NULL;
1931 struct file *file;
1932 int fd = proc_fd(inode);
99f89551 1933
99f89551 1934 if (task) {
28a6d671
EB		 1935 files = get_files_struct(task);
1936 put_task_struct(task);
1937 }
1938 if (files) {
1939 /*
1940 * We are not taking a ref to the file structure, so we must
1941 * hold ->file_lock.
1942 */
1943 spin_lock(&files->file_lock);
1944 file = fcheck_files(files, fd);
1945 if (file) {
3dcd25f3
JB		 1946 if (path) {
1947 *path = file->f_path;
1948 path_get(&file->f_path);
1949 }
27932742
MS		 1950 if (info)
1951 snprintf(info, PROC_FDINFO_MAX,
1952 "pos:\t%lli\n"
1953 "flags:\t0%o\n",
1954 (long long) file->f_pos,
1955 file->f_flags);
28a6d671
EB		 1956 spin_unlock(&files->file_lock);
1957 put_files_struct(files);
1958 return 0;
99f89551 1959 }
28a6d671
EB		 1960 spin_unlock(&files->file_lock);
1961 put_files_struct(files);
99f89551 1962 }
28a6d671 1963 return -ENOENT;
99f89551
EB		 1964}
1965
3dcd25f3 1966static int proc_fd_link(struct inode *inode, struct path *path)
27932742 1967{
3dcd25f3 1968 return proc_fd_info(inode, path, NULL);
27932742
MS		 1969}
1970
1da177e4
LT		 1971static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1972{
34286d66
NP		 1973 struct inode *inode;
1974 struct task_struct *task;
1975 int fd;
1da177e4 1976 struct files_struct *files;
c69e8d9c 1977 const struct cred *cred;
1da177e4 1978
34286d66
NP		 1979 if (nd && nd->flags & LOOKUP_RCU)
1980 return -ECHILD;
1981
1982 inode = dentry->d_inode;
1983 task = get_proc_task(inode);
1984 fd = proc_fd(inode);
1985
99f89551
EB		 1986 if (task) {
1987 files = get_files_struct(task);
1988 if (files) {
1989 rcu_read_lock();
1990 if (fcheck_files(files, fd)) {
1991 rcu_read_unlock();
1992 put_files_struct(files);
1993 if (task_dumpable(task)) {
c69e8d9c
DH		 1994 rcu_read_lock();
1995 cred = __task_cred(task);
1996 inode->i_uid = cred->euid;
1997 inode->i_gid = cred->egid;
1998 rcu_read_unlock();
99f89551
EB		 1999 } else {
2000 inode->i_uid = 0;
2001 inode->i_gid = 0;
2002 }
9ee8ab9f 2003 inode->i_mode &= ~(S_ISUID | S_ISGID);
99f89551
EB		 2004 security_task_to_inode(task, inode);
2005 put_task_struct(task);
2006 return 1;
2007 }
b835996f 2008 rcu_read_unlock();
1da177e4 2009 put_files_struct(files);
1da177e4 2010 }
99f89551 2011 put_task_struct(task);
1da177e4
LT		 2012 }
2013 d_drop(dentry);
2014 return 0;
2015}
2016
d72f71eb 2017static const struct dentry_operations tid_fd_dentry_operations =
1da177e4
LT		 2018{
2019 .d_revalidate = tid_fd_revalidate,
2020 .d_delete = pid_delete_dentry,
2021};
2022
444ceed8 2023static struct dentry *proc_fd_instantiate(struct inode *dir,
c5141e6d 2024 struct dentry *dentry, struct task_struct *task, const void *ptr)
1da177e4 2025{
c5141e6d 2026 unsigned fd = *(const unsigned *)ptr;
444ceed8
EB		 2027 struct file *file;
2028 struct files_struct *files;
2029 struct inode *inode;
2030 struct proc_inode *ei;
2031 struct dentry *error = ERR_PTR(-ENOENT);
1da177e4 2032
61a28784 2033 inode = proc_pid_make_inode(dir->i_sb, task);
1da177e4
LT		 2034 if (!inode)
2035 goto out;
2036 ei = PROC_I(inode);
aed7a6c4 2037 ei->fd = fd;
1da177e4
LT		 2038 files = get_files_struct(task);
2039 if (!files)
444ceed8 2040 goto out_iput;
1da177e4 2041 inode->i_mode = S_IFLNK;
ca99c1da
DS		 2042
2043 /*
2044 * We are not taking a ref to the file structure, so we must
2045 * hold ->file_lock.
2046 */
2047 spin_lock(&files->file_lock);
1da177e4
LT		 2048 file = fcheck_files(files, fd);
2049 if (!file)
444ceed8 2050 goto out_unlock;
aeb5d727 2051 if (file->f_mode & FMODE_READ)
1da177e4 2052 inode->i_mode |= S_IRUSR | S_IXUSR;
aeb5d727 2053 if (file->f_mode & FMODE_WRITE)
1da177e4 2054 inode->i_mode |= S_IWUSR | S_IXUSR;
ca99c1da 2055 spin_unlock(&files->file_lock);
1da177e4 2056 put_files_struct(files);
444ceed8 2057
1da177e4
LT		 2058 inode->i_op = &proc_pid_link_inode_operations;
2059 inode->i_size = 64;
2060 ei->op.proc_get_link = proc_fd_link;
fb045adb 2061 d_set_d_op(dentry, &tid_fd_dentry_operations);
1da177e4 2062 d_add(dentry, inode);
cd6a3ce9
EB		 2063 /* Close the race of the process dying before we return the dentry */
2064 if (tid_fd_revalidate(dentry, NULL))
444ceed8 2065 error = NULL;
1da177e4 2066
444ceed8
EB		 2067 out:
2068 return error;
2069out_unlock:
ca99c1da 2070 spin_unlock(&files->file_lock);
1da177e4 2071 put_files_struct(files);
444ceed8 2072out_iput:
1da177e4 2073 iput(inode);
cd6a3ce9 2074 goto out;
1da177e4
LT		 2075}
2076
27932742
MS		 2077static struct dentry *proc_lookupfd_common(struct inode *dir,
2078 struct dentry *dentry,
2079 instantiate_t instantiate)
444ceed8
EB		 2080{
2081 struct task_struct *task = get_proc_task(dir);
2082 unsigned fd = name_to_int(dentry);
2083 struct dentry *result = ERR_PTR(-ENOENT);
2084
2085 if (!task)
2086 goto out_no_task;
2087 if (fd == ~0U)
2088 goto out;
2089
27932742 2090 result = instantiate(dir, dentry, task, &fd);
444ceed8
EB		 2091out:
2092 put_task_struct(task);
2093out_no_task:
2094 return result;
2095}
2096
27932742
MS		 2097static int proc_readfd_common(struct file * filp, void * dirent,
2098 filldir_t filldir, instantiate_t instantiate)
28a6d671 2099{
2fddfeef 2100 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2101 struct inode *inode = dentry->d_inode;
2102 struct task_struct *p = get_proc_task(inode);
457c2510 2103 unsigned int fd, ino;
28a6d671 2104 int retval;
28a6d671 2105 struct files_struct * files;
1da177e4 2106
28a6d671
EB		 2107 retval = -ENOENT;
2108 if (!p)
2109 goto out_no_task;
2110 retval = 0;
28a6d671
EB		 2111
2112 fd = filp->f_pos;
2113 switch (fd) {
2114 case 0:
2115 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
2116 goto out;
2117 filp->f_pos++;
2118 case 1:
2119 ino = parent_ino(dentry);
2120 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2121 goto out;
2122 filp->f_pos++;
2123 default:
2124 files = get_files_struct(p);
2125 if (!files)
2126 goto out;
2127 rcu_read_lock();
28a6d671 2128 for (fd = filp->f_pos-2;
9b4f526c 2129 fd < files_fdtable(files)->max_fds;
28a6d671 2130 fd++, filp->f_pos++) {
27932742
MS		 2131 char name[PROC_NUMBUF];
2132 int len;
28a6d671
EB		 2133
2134 if (!fcheck_files(files, fd))
2135 continue;
2136 rcu_read_unlock();
2137
27932742
MS		 2138 len = snprintf(name, sizeof(name), "%d", fd);
2139 if (proc_fill_cache(filp, dirent, filldir,
2140 name, len, instantiate,
2141 p, &fd) < 0) {
28a6d671
EB		 2142 rcu_read_lock();
2143 break;
2144 }
2145 rcu_read_lock();
2146 }
2147 rcu_read_unlock();
2148 put_files_struct(files);
2149 }
2150out:
2151 put_task_struct(p);
2152out_no_task:
2153 return retval;
2154}
2155
27932742
MS		 2156static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
2157 struct nameidata *nd)
2158{
2159 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
2160}
2161
2162static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
2163{
2164 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
2165}
2166
2167static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
2168 size_t len, loff_t *ppos)
2169{
2170 char tmp[PROC_FDINFO_MAX];
3dcd25f3 2171 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
27932742
MS		 2172 if (!err)
2173 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
2174 return err;
2175}
2176
2177static const struct file_operations proc_fdinfo_file_operations = {
87df8424 2178 .open = nonseekable_open,
27932742 2179 .read = proc_fdinfo_read,
6038f373 2180 .llseek = no_llseek,
27932742
MS		 2181};
2182
00977a59 2183static const struct file_operations proc_fd_operations = {
28a6d671
EB		 2184 .read = generic_read_dir,
2185 .readdir = proc_readfd,
6038f373 2186 .llseek = default_llseek,
1da177e4
LT		 2187};
2188
8948e11f
AD		 2189/*
2190 * /proc/pid/fd needs a special permission handler so that a process can still
2191 * access /proc/self/fd after it has executed a setuid().
2192 */
b74c79e9 2193static int proc_fd_permission(struct inode *inode, int mask, unsigned int flags)
8948e11f
AD		 2194{
2195 int rv;
2196
b74c79e9
NP		 2197 if (flags & IPERM_FLAG_RCU)
2198 return -ECHILD;
2199 rv = generic_permission(inode, mask, flags, NULL);
8948e11f
AD		 2200 if (rv == 0)
2201 return 0;
2202 if (task_pid(current) == proc_pid(inode))
2203 rv = 0;
2204 return rv;
2205}
2206
1da177e4
LT		 2207/*
2208 * proc directories can do almost nothing..
2209 */
c5ef1c42 2210static const struct inode_operations proc_fd_inode_operations = {
1da177e4 2211 .lookup = proc_lookupfd,
8948e11f 2212 .permission = proc_fd_permission,
6d76fa58 2213 .setattr = proc_setattr,
1da177e4
LT		 2214};
2215
27932742
MS		 2216static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2217 struct dentry *dentry, struct task_struct *task, const void *ptr)
2218{
2219 unsigned fd = *(unsigned *)ptr;
2220 struct inode *inode;
2221 struct proc_inode *ei;
2222 struct dentry *error = ERR_PTR(-ENOENT);
2223
2224 inode = proc_pid_make_inode(dir->i_sb, task);
2225 if (!inode)
2226 goto out;
2227 ei = PROC_I(inode);
2228 ei->fd = fd;
2229 inode->i_mode = S_IFREG | S_IRUSR;
2230 inode->i_fop = &proc_fdinfo_file_operations;
fb045adb 2231 d_set_d_op(dentry, &tid_fd_dentry_operations);
27932742
MS		 2232 d_add(dentry, inode);
2233 /* Close the race of the process dying before we return the dentry */
2234 if (tid_fd_revalidate(dentry, NULL))
2235 error = NULL;
2236
2237 out:
2238 return error;
2239}
2240
2241static struct dentry *proc_lookupfdinfo(struct inode *dir,
2242 struct dentry *dentry,
2243 struct nameidata *nd)
2244{
2245 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2246}
2247
2248static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2249{
2250 return proc_readfd_common(filp, dirent, filldir,
2251 proc_fdinfo_instantiate);
2252}
2253
2254static const struct file_operations proc_fdinfo_operations = {
2255 .read = generic_read_dir,
2256 .readdir = proc_readfdinfo,
6038f373 2257 .llseek = default_llseek,
27932742
MS		 2258};
2259
2260/*
2261 * proc directories can do almost nothing..
2262 */
2263static const struct inode_operations proc_fdinfo_inode_operations = {
2264 .lookup = proc_lookupfdinfo,
2265 .setattr = proc_setattr,
2266};
2267
2268
444ceed8 2269static struct dentry *proc_pident_instantiate(struct inode *dir,
c5141e6d 2270 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2271{
c5141e6d 2272 const struct pid_entry *p = ptr;
444ceed8
EB		 2273 struct inode *inode;
2274 struct proc_inode *ei;
bd6daba9 2275 struct dentry *error = ERR_PTR(-ENOENT);
444ceed8 2276
61a28784 2277 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2278 if (!inode)
2279 goto out;
2280
2281 ei = PROC_I(inode);
2282 inode->i_mode = p->mode;
2283 if (S_ISDIR(inode->i_mode))
2284 inode->i_nlink = 2; /* Use getattr to fix if necessary */
2285 if (p->iop)
2286 inode->i_op = p->iop;
2287 if (p->fop)
2288 inode->i_fop = p->fop;
2289 ei->op = p->op;
fb045adb 2290 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2291 d_add(dentry, inode);
2292 /* Close the race of the process dying before we return the dentry */
2293 if (pid_revalidate(dentry, NULL))
2294 error = NULL;
2295out:
2296 return error;
2297}
2298
1da177e4
LT		 2299static struct dentry *proc_pident_lookup(struct inode *dir,
2300 struct dentry *dentry,
c5141e6d 2301 const struct pid_entry *ents,
7bcd6b0e 2302 unsigned int nents)
1da177e4 2303{
cd6a3ce9 2304 struct dentry *error;
99f89551 2305 struct task_struct *task = get_proc_task(dir);
c5141e6d 2306 const struct pid_entry *p, *last;
1da177e4 2307
cd6a3ce9 2308 error = ERR_PTR(-ENOENT);
1da177e4 2309
99f89551
EB		 2310 if (!task)
2311 goto out_no_task;
1da177e4 2312
20cdc894
EB		 2313 /*
2314 * Yes, it does not scale. And it should not. Don't add
2315 * new entries into /proc/<tgid>/ without very good reasons.
2316 */
7bcd6b0e
EB		 2317 last = &ents[nents - 1];
2318 for (p = ents; p <= last; p++) {
1da177e4
LT		 2319 if (p->len != dentry->d_name.len)
2320 continue;
2321 if (!memcmp(dentry->d_name.name, p->name, p->len))
2322 break;
2323 }
7bcd6b0e 2324 if (p > last)
1da177e4
LT		 2325 goto out;
2326
444ceed8 2327 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2328out:
99f89551
EB		 2329 put_task_struct(task);
2330out_no_task:
cd6a3ce9 2331 return error;
1da177e4
LT		 2332}
2333
c5141e6d
ED		 2334static int proc_pident_fill_cache(struct file *filp, void *dirent,
2335 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2336{
2337 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2338 proc_pident_instantiate, task, p);
2339}
2340
28a6d671
EB		 2341static int proc_pident_readdir(struct file *filp,
2342 void *dirent, filldir_t filldir,
c5141e6d 2343 const struct pid_entry *ents, unsigned int nents)
28a6d671
EB		 2344{
2345 int i;
2fddfeef 2346 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2347 struct inode *inode = dentry->d_inode;
2348 struct task_struct *task = get_proc_task(inode);
c5141e6d 2349 const struct pid_entry *p, *last;
28a6d671
EB		 2350 ino_t ino;
2351 int ret;
2352
2353 ret = -ENOENT;
2354 if (!task)
61a28784 2355 goto out_no_task;
28a6d671
EB		 2356
2357 ret = 0;
28a6d671
EB		 2358 i = filp->f_pos;
2359 switch (i) {
2360 case 0:
2361 ino = inode->i_ino;
2362 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2363 goto out;
2364 i++;
2365 filp->f_pos++;
2366 /* fall through */
2367 case 1:
2368 ino = parent_ino(dentry);
2369 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2370 goto out;
2371 i++;
2372 filp->f_pos++;
2373 /* fall through */
2374 default:
2375 i -= 2;
2376 if (i >= nents) {
2377 ret = 1;
2378 goto out;
2379 }
2380 p = ents + i;
7bcd6b0e
EB		 2381 last = &ents[nents - 1];
2382 while (p <= last) {
61a28784 2383 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
28a6d671
EB		 2384 goto out;
2385 filp->f_pos++;
2386 p++;
2387 }
2388 }
2389
2390 ret = 1;
2391out:
61a28784
EB		 2392 put_task_struct(task);
2393out_no_task:
28a6d671 2394 return ret;
1da177e4
LT		 2395}
2396
28a6d671
EB		 2397#ifdef CONFIG_SECURITY
2398static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2399 size_t count, loff_t *ppos)
2400{
2fddfeef 2401 struct inode * inode = file->f_path.dentry->d_inode;
04ff9708 2402 char *p = NULL;
28a6d671
EB		 2403 ssize_t length;
2404 struct task_struct *task = get_proc_task(inode);
2405
28a6d671 2406 if (!task)
04ff9708 2407 return -ESRCH;
28a6d671
EB		 2408
2409 length = security_getprocattr(task,
2fddfeef 2410 (char*)file->f_path.dentry->d_name.name,
04ff9708 2411 &p);
28a6d671 2412 put_task_struct(task);
04ff9708
AV		 2413 if (length > 0)
2414 length = simple_read_from_buffer(buf, count, ppos, p, length);
2415 kfree(p);
28a6d671 2416 return length;
1da177e4
LT		 2417}
2418
28a6d671
EB		 2419static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2420 size_t count, loff_t *ppos)
2421{
2fddfeef 2422 struct inode * inode = file->f_path.dentry->d_inode;
28a6d671
EB		 2423 char *page;
2424 ssize_t length;
2425 struct task_struct *task = get_proc_task(inode);
2426
2427 length = -ESRCH;
2428 if (!task)
2429 goto out_no_task;
2430 if (count > PAGE_SIZE)
2431 count = PAGE_SIZE;
2432
2433 /* No partial writes. */
2434 length = -EINVAL;
2435 if (*ppos != 0)
2436 goto out;
2437
2438 length = -ENOMEM;
e12ba74d 2439 page = (char*)__get_free_page(GFP_TEMPORARY);
28a6d671
EB		 2440 if (!page)
2441 goto out;
2442
2443 length = -EFAULT;
2444 if (copy_from_user(page, buf, count))
2445 goto out_free;
2446
107db7c7 2447 /* Guard against adverse ptrace interaction */
9b1bf12d 2448 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2449 if (length < 0)
2450 goto out_free;
2451
28a6d671 2452 length = security_setprocattr(task,
2fddfeef 2453 (char*)file->f_path.dentry->d_name.name,
28a6d671 2454 (void*)page, count);
9b1bf12d 2455 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671
EB		 2456out_free:
2457 free_page((unsigned long) page);
2458out:
2459 put_task_struct(task);
2460out_no_task:
2461 return length;
2462}
2463
00977a59 2464static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2465 .read = proc_pid_attr_read,
2466 .write = proc_pid_attr_write,
87df8424 2467 .llseek = generic_file_llseek,
28a6d671
EB		 2468};
2469
c5141e6d 2470static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2471 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2472 REG("prev", S_IRUGO, proc_pid_attr_operations),
2473 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2474 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2475 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2476 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2477};
2478
72d9dcfc 2479static int proc_attr_dir_readdir(struct file * filp,
28a6d671
EB		 2480 void * dirent, filldir_t filldir)
2481{
2482 return proc_pident_readdir(filp,dirent,filldir,
72d9dcfc 2483 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2484}
2485
00977a59 2486static const struct file_operations proc_attr_dir_operations = {
1da177e4 2487 .read = generic_read_dir,
72d9dcfc 2488 .readdir = proc_attr_dir_readdir,
6038f373 2489 .llseek = default_llseek,
1da177e4
LT		 2490};
2491
72d9dcfc 2492static struct dentry *proc_attr_dir_lookup(struct inode *dir,
28a6d671
EB		 2493 struct dentry *dentry, struct nameidata *nd)
2494{
7bcd6b0e
EB		 2495 return proc_pident_lookup(dir, dentry,
2496 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2497}
2498
c5ef1c42 2499static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2500 .lookup = proc_attr_dir_lookup,
99f89551 2501 .getattr = pid_getattr,
6d76fa58 2502 .setattr = proc_setattr,
1da177e4
LT		 2503};
2504
28a6d671
EB		 2505#endif
2506
698ba7b5 2507#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2508static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2509 size_t count, loff_t *ppos)
2510{
2511 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2512 struct mm_struct *mm;
2513 char buffer[PROC_NUMBUF];
2514 size_t len;
2515 int ret;
2516
2517 if (!task)
2518 return -ESRCH;
2519
2520 ret = 0;
2521 mm = get_task_mm(task);
2522 if (mm) {
2523 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2524 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2525 MMF_DUMP_FILTER_SHIFT));
2526 mmput(mm);
2527 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2528 }
2529
2530 put_task_struct(task);
2531
2532 return ret;
2533}
2534
2535static ssize_t proc_coredump_filter_write(struct file *file,
2536 const char __user *buf,
2537 size_t count,
2538 loff_t *ppos)
2539{
2540 struct task_struct *task;
2541 struct mm_struct *mm;
2542 char buffer[PROC_NUMBUF], *end;
2543 unsigned int val;
2544 int ret;
2545 int i;
2546 unsigned long mask;
2547
2548 ret = -EFAULT;
2549 memset(buffer, 0, sizeof(buffer));
2550 if (count > sizeof(buffer) - 1)
2551 count = sizeof(buffer) - 1;
2552 if (copy_from_user(buffer, buf, count))
2553 goto out_no_task;
2554
2555 ret = -EINVAL;
2556 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2557 if (*end == '\n')
2558 end++;
2559 if (end - buffer == 0)
2560 goto out_no_task;
2561
2562 ret = -ESRCH;
2563 task = get_proc_task(file->f_dentry->d_inode);
2564 if (!task)
2565 goto out_no_task;
2566
2567 ret = end - buffer;
2568 mm = get_task_mm(task);
2569 if (!mm)
2570 goto out_no_mm;
2571
2572 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2573 if (val & mask)
2574 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2575 else
2576 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2577 }
2578
2579 mmput(mm);
2580 out_no_mm:
2581 put_task_struct(task);
2582 out_no_task:
2583 return ret;
2584}
2585
2586static const struct file_operations proc_coredump_filter_operations = {
2587 .read = proc_coredump_filter_read,
2588 .write = proc_coredump_filter_write,
87df8424 2589 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2590};
2591#endif
2592
28a6d671
EB		 2593/*
2594 * /proc/self:
2595 */
2596static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2597 int buflen)
2598{
488e5bc4 2599 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2600 pid_t tgid = task_tgid_nr_ns(current, ns);
28a6d671 2601 char tmp[PROC_NUMBUF];
b55fcb22 2602 if (!tgid)
488e5bc4 2603 return -ENOENT;
b55fcb22 2604 sprintf(tmp, "%d", tgid);
28a6d671
EB		 2605 return vfs_readlink(dentry,buffer,buflen,tmp);
2606}
2607
2608static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2609{
488e5bc4 2610 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2611 pid_t tgid = task_tgid_nr_ns(current, ns);
7fee4868
AV		 2612 char *name = ERR_PTR(-ENOENT);
2613 if (tgid) {
2614 name = __getname();
2615 if (!name)
2616 name = ERR_PTR(-ENOMEM);
2617 else
2618 sprintf(name, "%d", tgid);
2619 }
2620 nd_set_link(nd, name);
2621 return NULL;
2622}
2623
2624static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2625 void *cookie)
2626{
2627 char *s = nd_get_link(nd);
2628 if (!IS_ERR(s))
2629 __putname(s);
28a6d671
EB		 2630}
2631
c5ef1c42 2632static const struct inode_operations proc_self_inode_operations = {
28a6d671
EB		 2633 .readlink = proc_self_readlink,
2634 .follow_link = proc_self_follow_link,
7fee4868 2635 .put_link = proc_self_put_link,
28a6d671
EB		 2636};
2637
801199ce
EB		 2638/*
2639 * proc base
2640 *
2641 * These are the directory entries in the root directory of /proc
2642 * that properly belong to the /proc filesystem, as they describe
2643 * describe something that is process related.
2644 */
c5141e6d 2645static const struct pid_entry proc_base_stuff[] = {
61a28784 2646 NOD("self", S_IFLNK|S_IRWXUGO,
801199ce 2647 &proc_self_inode_operations, NULL, {}),
801199ce
EB		 2648};
2649
2650/*
2651 * Exceptional case: normally we are not allowed to unhash a busy
2652 * directory. In this case, however, we can do it - no aliasing problems
2653 * due to the way we treat inodes.
2654 */
2655static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
2656{
34286d66
NP		 2657 struct inode *inode;
2658 struct task_struct *task;
2659
2660 if (nd->flags & LOOKUP_RCU)
2661 return -ECHILD;
2662
2663 inode = dentry->d_inode;
2664 task = get_proc_task(inode);
801199ce
EB		 2665 if (task) {
2666 put_task_struct(task);
2667 return 1;
2668 }
2669 d_drop(dentry);
2670 return 0;
2671}
2672
d72f71eb 2673static const struct dentry_operations proc_base_dentry_operations =
801199ce
EB		 2674{
2675 .d_revalidate = proc_base_revalidate,
2676 .d_delete = pid_delete_dentry,
2677};
2678
444ceed8 2679static struct dentry *proc_base_instantiate(struct inode *dir,
c5141e6d 2680 struct dentry *dentry, struct task_struct *task, const void *ptr)
801199ce 2681{
c5141e6d 2682 const struct pid_entry *p = ptr;
801199ce 2683 struct inode *inode;
801199ce 2684 struct proc_inode *ei;
73d36460 2685 struct dentry *error;
801199ce
EB		 2686
2687 /* Allocate the inode */
2688 error = ERR_PTR(-ENOMEM);
2689 inode = new_inode(dir->i_sb);
2690 if (!inode)
2691 goto out;
2692
2693 /* Initialize the inode */
2694 ei = PROC_I(inode);
85fe4025 2695 inode->i_ino = get_next_ino();
801199ce 2696 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
801199ce
EB		 2697
2698 /*
2699 * grab the reference to the task.
2700 */
1a657f78 2701 ei->pid = get_task_pid(task, PIDTYPE_PID);
801199ce
EB		 2702 if (!ei->pid)
2703 goto out_iput;
2704
801199ce
EB		 2705 inode->i_mode = p->mode;
2706 if (S_ISDIR(inode->i_mode))
2707 inode->i_nlink = 2;
2708 if (S_ISLNK(inode->i_mode))
2709 inode->i_size = 64;
2710 if (p->iop)
2711 inode->i_op = p->iop;
2712 if (p->fop)
2713 inode->i_fop = p->fop;
2714 ei->op = p->op;
fb045adb 2715 d_set_d_op(dentry, &proc_base_dentry_operations);
801199ce
EB		 2716 d_add(dentry, inode);
2717 error = NULL;
2718out:
801199ce
EB		 2719 return error;
2720out_iput:
2721 iput(inode);
2722 goto out;
2723}
2724
444ceed8
EB		 2725static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2726{
2727 struct dentry *error;
2728 struct task_struct *task = get_proc_task(dir);
c5141e6d 2729 const struct pid_entry *p, *last;
444ceed8
EB		 2730
2731 error = ERR_PTR(-ENOENT);
2732
2733 if (!task)
2734 goto out_no_task;
2735
2736 /* Lookup the directory entry */
7bcd6b0e
EB		 2737 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2738 for (p = proc_base_stuff; p <= last; p++) {
444ceed8
EB		 2739 if (p->len != dentry->d_name.len)
2740 continue;
2741 if (!memcmp(dentry->d_name.name, p->name, p->len))
2742 break;
2743 }
7bcd6b0e 2744 if (p > last)
444ceed8
EB		 2745 goto out;
2746
2747 error = proc_base_instantiate(dir, dentry, task, p);
2748
2749out:
2750 put_task_struct(task);
2751out_no_task:
2752 return error;
2753}
2754
c5141e6d
ED		 2755static int proc_base_fill_cache(struct file *filp, void *dirent,
2756 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2757{
2758 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2759 proc_base_instantiate, task, p);
2760}
2761
aba76fdb 2762#ifdef CONFIG_TASK_IO_ACCOUNTING
297c5d92
AR		 2763static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2764{
940389b8 2765 struct task_io_accounting acct = task->ioac;
5995477a
AR		 2766 unsigned long flags;
2767
2768 if (whole && lock_task_sighand(task, &flags)) {
2769 struct task_struct *t = task;
2770
2771 task_io_accounting_add(&acct, &task->signal->ioac);
2772 while_each_thread(task, t)
2773 task_io_accounting_add(&acct, &t->ioac);
2774
2775 unlock_task_sighand(task, &flags);
297c5d92 2776 }
aba76fdb
AM		 2777 return sprintf(buffer,
2778 "rchar: %llu\n"
2779 "wchar: %llu\n"
2780 "syscr: %llu\n"
2781 "syscw: %llu\n"
2782 "read_bytes: %llu\n"
2783 "write_bytes: %llu\n"
2784 "cancelled_write_bytes: %llu\n",
7c44319d
AB		 2785 (unsigned long long)acct.rchar,
2786 (unsigned long long)acct.wchar,
2787 (unsigned long long)acct.syscr,
2788 (unsigned long long)acct.syscw,
2789 (unsigned long long)acct.read_bytes,
2790 (unsigned long long)acct.write_bytes,
2791 (unsigned long long)acct.cancelled_write_bytes);
297c5d92
AR		 2792}
2793
2794static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2795{
2796 return do_io_accounting(task, buffer, 0);
aba76fdb 2797}
297c5d92
AR		 2798
2799static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2800{
2801 return do_io_accounting(task, buffer, 1);
2802}
2803#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2804
47830723
KC		 2805static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2806 struct pid *pid, struct task_struct *task)
2807{
2808 seq_printf(m, "%08x\n", task->personality);
2809 return 0;
2810}
2811
28a6d671
EB		 2812/*
2813 * Thread groups
2814 */
00977a59 2815static const struct file_operations proc_task_operations;
c5ef1c42 2816static const struct inode_operations proc_task_inode_operations;
20cdc894 2817
c5141e6d 2818static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2819 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2820 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2821 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
b2211a36 2822#ifdef CONFIG_NET
631f9c18 2823 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 2824#endif
631f9c18
AD		 2825 REG("environ", S_IRUSR, proc_environ_operations),
2826 INF("auxv", S_IRUSR, proc_pid_auxv),
2827 ONE("status", S_IRUGO, proc_pid_status),
2828 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 2829 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 2830#ifdef CONFIG_SCHED_DEBUG
631f9c18 2831 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
5091faa4
MG		 2832#endif
2833#ifdef CONFIG_SCHED_AUTOGROUP
2834 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
ebcb6734 2835#endif
4614a696 2836 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 2837#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 2838 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 2839#endif
631f9c18
AD		 2840 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2841 ONE("stat", S_IRUGO, proc_tgid_stat),
2842 ONE("statm", S_IRUGO, proc_pid_statm),
2843 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 2844#ifdef CONFIG_NUMA
631f9c18 2845 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 2846#endif
631f9c18
AD		 2847 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2848 LNK("cwd", proc_cwd_link),
2849 LNK("root", proc_root_link),
2850 LNK("exe", proc_exe_link),
2851 REG("mounts", S_IRUGO, proc_mounts_operations),
2852 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2853 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 2854#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 2855 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2856 REG("smaps", S_IRUGO, proc_smaps_operations),
2857 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 2858#endif
2859#ifdef CONFIG_SECURITY
631f9c18 2860 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 2861#endif
2862#ifdef CONFIG_KALLSYMS
631f9c18 2863 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 2864#endif
2ec220e2
KC		 2865#ifdef CONFIG_STACKTRACE
2866 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 2867#endif
2868#ifdef CONFIG_SCHEDSTATS
631f9c18 2869 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 2870#endif
9745512c 2871#ifdef CONFIG_LATENCYTOP
631f9c18 2872 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 2873#endif
8793d854 2874#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 2875 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 2876#endif
2877#ifdef CONFIG_CGROUPS
631f9c18 2878 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 2879#endif
631f9c18
AD		 2880 INF("oom_score", S_IRUGO, proc_oom_score),
2881 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 2882 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 2883#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 2884 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2885 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 2886#endif
f4f154fd 2887#ifdef CONFIG_FAULT_INJECTION
631f9c18 2888 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 2889#endif
698ba7b5 2890#ifdef CONFIG_ELF_CORE
631f9c18 2891 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 2892#endif
aba76fdb 2893#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 2894 INF("io", S_IRUGO, proc_tgid_io_accounting),
aba76fdb 2895#endif
28a6d671 2896};
1da177e4 2897
28a6d671 2898static int proc_tgid_base_readdir(struct file * filp,
1da177e4
LT		 2899 void * dirent, filldir_t filldir)
2900{
2901 return proc_pident_readdir(filp,dirent,filldir,
28a6d671 2902 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2903}
2904
00977a59 2905static const struct file_operations proc_tgid_base_operations = {
1da177e4 2906 .read = generic_read_dir,
28a6d671 2907 .readdir = proc_tgid_base_readdir,
6038f373 2908 .llseek = default_llseek,
1da177e4
LT		 2909};
2910
28a6d671 2911static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 2912 return proc_pident_lookup(dir, dentry,
2913 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2914}
2915
c5ef1c42 2916static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 2917 .lookup = proc_tgid_base_lookup,
99f89551 2918 .getattr = pid_getattr,
6d76fa58 2919 .setattr = proc_setattr,
1da177e4 2920};
1da177e4 2921
60347f67 2922static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 2923{
48e6484d 2924 struct dentry *dentry, *leader, *dir;
8578cea7 2925 char buf[PROC_NUMBUF];
48e6484d
EB		 2926 struct qstr name;
2927
2928 name.name = buf;
60347f67
PE		 2929 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2930 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 2931 if (dentry) {
29f12ca3 2932 shrink_dcache_parent(dentry);
48e6484d
EB		 2933 d_drop(dentry);
2934 dput(dentry);
2935 }
1da177e4 2936
48e6484d 2937 name.name = buf;
60347f67
PE		 2938 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2939 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 2940 if (!leader)
2941 goto out;
1da177e4 2942
48e6484d
EB		 2943 name.name = "task";
2944 name.len = strlen(name.name);
2945 dir = d_hash_and_lookup(leader, &name);
2946 if (!dir)
2947 goto out_put_leader;
2948
2949 name.name = buf;
60347f67 2950 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 2951 dentry = d_hash_and_lookup(dir, &name);
2952 if (dentry) {
2953 shrink_dcache_parent(dentry);
2954 d_drop(dentry);
2955 dput(dentry);
1da177e4 2956 }
48e6484d
EB		 2957
2958 dput(dir);
2959out_put_leader:
2960 dput(leader);
2961out:
2962 return;
1da177e4
LT		 2963}
2964
0895e91d
RD		 2965/**
2966 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2967 * @task: task that should be flushed.
2968 *
2969 * When flushing dentries from proc, one needs to flush them from global
60347f67 2970 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 2971 * in. This call is supposed to do all of this job.
2972 *
2973 * Looks in the dcache for
2974 * /proc/@pid
2975 * /proc/@tgid/task/@pid
2976 * if either directory is present flushes it and all of it'ts children
2977 * from the dcache.
2978 *
2979 * It is safe and reasonable to cache /proc entries for a task until
2980 * that task exits. After that they just clog up the dcache with
2981 * useless entries, possibly causing useful dcache entries to be
2982 * flushed instead. This routine is proved to flush those useless
2983 * dcache entries at process exit time.
2984 *
2985 * NOTE: This routine is just an optimization so it does not guarantee
2986 * that no dcache entries will exist at process exit time it
2987 * just makes it very unlikely that any will persist.
60347f67
PE		 2988 */
2989
2990void proc_flush_task(struct task_struct *task)
2991{
9fcc2d15 2992 int i;
9b4d1cbe 2993 struct pid *pid, *tgid;
130f77ec
PE		 2994 struct upid *upid;
2995
130f77ec 2996 pid = task_pid(task);
9b4d1cbe 2997 tgid = task_tgid(task);
130f77ec 2998
9fcc2d15 2999 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 3000 upid = &pid->numbers[i];
3001 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 3002 tgid->numbers[i].nr);
130f77ec 3003 }
6f4e6433
PE		 3004
3005 upid = &pid->numbers[pid->level];
3006 if (upid->nr == 1)
3007 pid_ns_release_proc(upid->ns);
60347f67
PE		 3008}
3009
9711ef99
AB		 3010static struct dentry *proc_pid_instantiate(struct inode *dir,
3011 struct dentry * dentry,
c5141e6d 3012 struct task_struct *task, const void *ptr)
444ceed8
EB		 3013{
3014 struct dentry *error = ERR_PTR(-ENOENT);
3015 struct inode *inode;
3016
61a28784 3017 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3018 if (!inode)
3019 goto out;
3020
3021 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3022 inode->i_op = &proc_tgid_base_inode_operations;
3023 inode->i_fop = &proc_tgid_base_operations;
3024 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 3025
3026 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
3027 ARRAY_SIZE(tgid_base_stuff));
444ceed8 3028
fb045adb 3029 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3030
3031 d_add(dentry, inode);
3032 /* Close the race of the process dying before we return the dentry */
3033 if (pid_revalidate(dentry, NULL))
3034 error = NULL;
3035out:
3036 return error;
3037}
3038
1da177e4
LT		 3039struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3040{
73d36460 3041 struct dentry *result;
1da177e4 3042 struct task_struct *task;
1da177e4 3043 unsigned tgid;
b488893a 3044 struct pid_namespace *ns;
1da177e4 3045
801199ce
EB		 3046 result = proc_base_lookup(dir, dentry);
3047 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
3048 goto out;
3049
1da177e4
LT		 3050 tgid = name_to_int(dentry);
3051 if (tgid == ~0U)
3052 goto out;
3053
b488893a 3054 ns = dentry->d_sb->s_fs_info;
de758734 3055 rcu_read_lock();
b488893a 3056 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 3057 if (task)
3058 get_task_struct(task);
de758734 3059 rcu_read_unlock();
1da177e4
LT		 3060 if (!task)
3061 goto out;
3062
444ceed8 3063 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 3064 put_task_struct(task);
1da177e4 3065out:
cd6a3ce9 3066 return result;
1da177e4
LT		 3067}
3068
1da177e4 3069/*
0804ef4b 3070 * Find the first task with tgid >= tgid
0bc58a91 3071 *
1da177e4 3072 */
19fd4bb2
EB		 3073struct tgid_iter {
3074 unsigned int tgid;
0804ef4b 3075 struct task_struct *task;
19fd4bb2
EB		 3076};
3077static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3078{
0804ef4b 3079 struct pid *pid;
1da177e4 3080
19fd4bb2
EB		 3081 if (iter.task)
3082 put_task_struct(iter.task);
454cc105 3083 rcu_read_lock();
0804ef4b 3084retry:
19fd4bb2
EB		 3085 iter.task = NULL;
3086 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 3087 if (pid) {
19fd4bb2
EB		 3088 iter.tgid = pid_nr_ns(pid, ns);
3089 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 3090 /* What we to know is if the pid we have find is the
3091 * pid of a thread_group_leader. Testing for task
3092 * being a thread_group_leader is the obvious thing
3093 * todo but there is a window when it fails, due to
3094 * the pid transfer logic in de_thread.
3095 *
3096 * So we perform the straight forward test of seeing
3097 * if the pid we have found is the pid of a thread
3098 * group leader, and don't worry if the task we have
3099 * found doesn't happen to be a thread group leader.
3100 * As we don't care in the case of readdir.
3101 */
19fd4bb2
EB		 3102 if (!iter.task || !has_group_leader_pid(iter.task)) {
3103 iter.tgid += 1;
0804ef4b 3104 goto retry;
19fd4bb2
EB		 3105 }
3106 get_task_struct(iter.task);
0bc58a91 3107 }
454cc105 3108 rcu_read_unlock();
19fd4bb2 3109 return iter;
1da177e4
LT		 3110}
3111
7bcd6b0e 3112#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
0804ef4b 3113
61a28784 3114static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
19fd4bb2 3115 struct tgid_iter iter)
61a28784
EB		 3116{
3117 char name[PROC_NUMBUF];
19fd4bb2 3118 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
61a28784 3119 return proc_fill_cache(filp, dirent, filldir, name, len,
19fd4bb2 3120 proc_pid_instantiate, iter.task, NULL);
61a28784
EB		 3121}
3122
1da177e4
LT		 3123/* for the /proc/ directory itself, after non-process stuff has been done */
3124int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3125{
1da177e4 3126 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2fddfeef 3127 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
19fd4bb2 3128 struct tgid_iter iter;
b488893a 3129 struct pid_namespace *ns;
1da177e4 3130
61a28784
EB		 3131 if (!reaper)
3132 goto out_no_task;
3133
7bcd6b0e 3134 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
c5141e6d 3135 const struct pid_entry *p = &proc_base_stuff[nr];
61a28784 3136 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
801199ce 3137 goto out;
1da177e4
LT		 3138 }
3139
b488893a 3140 ns = filp->f_dentry->d_sb->s_fs_info;
19fd4bb2
EB		 3141 iter.task = NULL;
3142 iter.tgid = filp->f_pos - TGID_OFFSET;
3143 for (iter = next_tgid(ns, iter);
3144 iter.task;
3145 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3146 filp->f_pos = iter.tgid + TGID_OFFSET;
3147 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
3148 put_task_struct(iter.task);
0804ef4b 3149 goto out;
1da177e4 3150 }
0bc58a91 3151 }
0804ef4b
EB		 3152 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3153out:
61a28784
EB		 3154 put_task_struct(reaper);
3155out_no_task:
0bc58a91
EB		 3156 return 0;
3157}
1da177e4 3158
28a6d671
EB		 3159/*
3160 * Tasks
3161 */
c5141e6d 3162static const struct pid_entry tid_base_stuff[] = {
631f9c18 3163 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3164 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
631f9c18
AD		 3165 REG("environ", S_IRUSR, proc_environ_operations),
3166 INF("auxv", S_IRUSR, proc_pid_auxv),
3167 ONE("status", S_IRUGO, proc_pid_status),
3168 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 3169 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3170#ifdef CONFIG_SCHED_DEBUG
631f9c18 3171 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3172#endif
4614a696 3173 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3174#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 3175 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 3176#endif
631f9c18
AD		 3177 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3178 ONE("stat", S_IRUGO, proc_tid_stat),
3179 ONE("statm", S_IRUGO, proc_pid_statm),
3180 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3181#ifdef CONFIG_NUMA
631f9c18 3182 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3183#endif
631f9c18
AD		 3184 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3185 LNK("cwd", proc_cwd_link),
3186 LNK("root", proc_root_link),
3187 LNK("exe", proc_exe_link),
3188 REG("mounts", S_IRUGO, proc_mounts_operations),
3189 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3190#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3191 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3192 REG("smaps", S_IRUGO, proc_smaps_operations),
3193 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 3194#endif
3195#ifdef CONFIG_SECURITY
631f9c18 3196 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3197#endif
3198#ifdef CONFIG_KALLSYMS
631f9c18 3199 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3200#endif
2ec220e2
KC		 3201#ifdef CONFIG_STACKTRACE
3202 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 3203#endif
3204#ifdef CONFIG_SCHEDSTATS
631f9c18 3205 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3206#endif
9745512c 3207#ifdef CONFIG_LATENCYTOP
631f9c18 3208 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3209#endif
8793d854 3210#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3211 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3212#endif
3213#ifdef CONFIG_CGROUPS
631f9c18 3214 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3215#endif
631f9c18
AD		 3216 INF("oom_score", S_IRUGO, proc_oom_score),
3217 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3218 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3219#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 3220 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3221 REG("sessionid", S_IRUSR, proc_sessionid_operations),
28a6d671 3222#endif
f4f154fd 3223#ifdef CONFIG_FAULT_INJECTION
631f9c18 3224 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3225#endif
297c5d92 3226#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 3227 INF("io", S_IRUGO, proc_tid_io_accounting),
297c5d92 3228#endif
28a6d671
EB		 3229};
3230
3231static int proc_tid_base_readdir(struct file * filp,
3232 void * dirent, filldir_t filldir)
3233{
3234 return proc_pident_readdir(filp,dirent,filldir,
3235 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3236}
3237
3238static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3239 return proc_pident_lookup(dir, dentry,
3240 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3241}
3242
00977a59 3243static const struct file_operations proc_tid_base_operations = {
28a6d671
EB		 3244 .read = generic_read_dir,
3245 .readdir = proc_tid_base_readdir,
6038f373 3246 .llseek = default_llseek,
28a6d671
EB		 3247};
3248
c5ef1c42 3249static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3250 .lookup = proc_tid_base_lookup,
3251 .getattr = pid_getattr,
3252 .setattr = proc_setattr,
3253};
3254
444ceed8 3255static struct dentry *proc_task_instantiate(struct inode *dir,
c5141e6d 3256 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8
EB		 3257{
3258 struct dentry *error = ERR_PTR(-ENOENT);
3259 struct inode *inode;
61a28784 3260 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3261
3262 if (!inode)
3263 goto out;
3264 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3265 inode->i_op = &proc_tid_base_inode_operations;
3266 inode->i_fop = &proc_tid_base_operations;
3267 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 3268
3269 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
3270 ARRAY_SIZE(tid_base_stuff));
444ceed8 3271
fb045adb 3272 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3273
3274 d_add(dentry, inode);
3275 /* Close the race of the process dying before we return the dentry */
3276 if (pid_revalidate(dentry, NULL))
3277 error = NULL;
3278out:
3279 return error;
3280}
3281
28a6d671
EB		 3282static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3283{
3284 struct dentry *result = ERR_PTR(-ENOENT);
3285 struct task_struct *task;
3286 struct task_struct *leader = get_proc_task(dir);
28a6d671 3287 unsigned tid;
b488893a 3288 struct pid_namespace *ns;
28a6d671
EB		 3289
3290 if (!leader)
3291 goto out_no_task;
3292
3293 tid = name_to_int(dentry);
3294 if (tid == ~0U)
3295 goto out;
3296
b488893a 3297 ns = dentry->d_sb->s_fs_info;
28a6d671 3298 rcu_read_lock();
b488893a 3299 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3300 if (task)
3301 get_task_struct(task);
3302 rcu_read_unlock();
3303 if (!task)
3304 goto out;
bac0abd6 3305 if (!same_thread_group(leader, task))
28a6d671
EB		 3306 goto out_drop_task;
3307
444ceed8 3308 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3309out_drop_task:
3310 put_task_struct(task);
3311out:
3312 put_task_struct(leader);
3313out_no_task:
3314 return result;
3315}
3316
0bc58a91
EB		 3317/*
3318 * Find the first tid of a thread group to return to user space.
3319 *
3320 * Usually this is just the thread group leader, but if the users
3321 * buffer was too small or there was a seek into the middle of the
3322 * directory we have more work todo.
3323 *
3324 * In the case of a short read we start with find_task_by_pid.
3325 *
3326 * In the case of a seek we start with the leader and walk nr
3327 * threads past it.
3328 */
cc288738 3329static struct task_struct *first_tid(struct task_struct *leader,
b488893a 3330 int tid, int nr, struct pid_namespace *ns)
0bc58a91 3331{
a872ff0c 3332 struct task_struct *pos;
1da177e4 3333
cc288738 3334 rcu_read_lock();
0bc58a91
EB		 3335 /* Attempt to start with the pid of a thread */
3336 if (tid && (nr > 0)) {
b488893a 3337 pos = find_task_by_pid_ns(tid, ns);
a872ff0c
ON		 3338 if (pos && (pos->group_leader == leader))
3339 goto found;
0bc58a91 3340 }
1da177e4 3341
0bc58a91 3342 /* If nr exceeds the number of threads there is nothing todo */
a872ff0c
ON		 3343 pos = NULL;
3344 if (nr && nr >= get_nr_threads(leader))
3345 goto out;
1da177e4 3346
a872ff0c
ON		 3347 /* If we haven't found our starting place yet start
3348 * with the leader and walk nr threads forward.
0bc58a91 3349 */
a872ff0c
ON		 3350 for (pos = leader; nr > 0; --nr) {
3351 pos = next_thread(pos);
3352 if (pos == leader) {
3353 pos = NULL;
3354 goto out;
3355 }
1da177e4 3356 }
a872ff0c
ON		 3357found:
3358 get_task_struct(pos);
3359out:
cc288738 3360 rcu_read_unlock();
0bc58a91
EB		 3361 return pos;
3362}
3363
3364/*
3365 * Find the next thread in the thread list.
3366 * Return NULL if there is an error or no next thread.
3367 *
3368 * The reference to the input task_struct is released.
3369 */
3370static struct task_struct *next_tid(struct task_struct *start)
3371{
c1df7fb8 3372 struct task_struct *pos = NULL;
cc288738 3373 rcu_read_lock();
c1df7fb8 3374 if (pid_alive(start)) {
0bc58a91 3375 pos = next_thread(start);
c1df7fb8
ON		 3376 if (thread_group_leader(pos))
3377 pos = NULL;
3378 else
3379 get_task_struct(pos);
3380 }
cc288738 3381 rcu_read_unlock();
0bc58a91
EB		 3382 put_task_struct(start);
3383 return pos;
1da177e4
LT		 3384}
3385
61a28784
EB		 3386static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3387 struct task_struct *task, int tid)
3388{
3389 char name[PROC_NUMBUF];
3390 int len = snprintf(name, sizeof(name), "%d", tid);
3391 return proc_fill_cache(filp, dirent, filldir, name, len,
3392 proc_task_instantiate, task, NULL);
3393}
3394
1da177e4
LT		 3395/* for the /proc/TGID/task/ directories */
3396static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3397{
2fddfeef 3398 struct dentry *dentry = filp->f_path.dentry;
1da177e4 3399 struct inode *inode = dentry->d_inode;
7d895244 3400 struct task_struct *leader = NULL;
0bc58a91 3401 struct task_struct *task;
1da177e4
LT		 3402 int retval = -ENOENT;
3403 ino_t ino;
0bc58a91 3404 int tid;
b488893a 3405 struct pid_namespace *ns;
1da177e4 3406
7d895244
GC		 3407 task = get_proc_task(inode);
3408 if (!task)
3409 goto out_no_task;
3410 rcu_read_lock();
3411 if (pid_alive(task)) {
3412 leader = task->group_leader;
3413 get_task_struct(leader);
3414 }
3415 rcu_read_unlock();
3416 put_task_struct(task);
99f89551
EB		 3417 if (!leader)
3418 goto out_no_task;
1da177e4
LT		 3419 retval = 0;
3420
ee568b25 3421 switch ((unsigned long)filp->f_pos) {
1da177e4
LT		 3422 case 0:
3423 ino = inode->i_ino;
ee6f779b 3424 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3425 goto out;
ee6f779b 3426 filp->f_pos++;
1da177e4
LT		 3427 /* fall through */
3428 case 1:
3429 ino = parent_ino(dentry);
ee6f779b 3430 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3431 goto out;
ee6f779b 3432 filp->f_pos++;
1da177e4
LT		 3433 /* fall through */
3434 }
3435
0bc58a91
EB		 3436 /* f_version caches the tgid value that the last readdir call couldn't
3437 * return. lseek aka telldir automagically resets f_version to 0.
3438 */
b488893a 3439 ns = filp->f_dentry->d_sb->s_fs_info;
2b47c361 3440 tid = (int)filp->f_version;
0bc58a91 3441 filp->f_version = 0;
ee6f779b 3442 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
0bc58a91 3443 task;
ee6f779b 3444 task = next_tid(task), filp->f_pos++) {
b488893a 3445 tid = task_pid_nr_ns(task, ns);
61a28784 3446 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
0bc58a91
EB		 3447 /* returning this tgid failed, save it as the first
3448 * pid for the next readir call */
2b47c361 3449 filp->f_version = (u64)tid;
0bc58a91 3450 put_task_struct(task);
1da177e4 3451 break;
0bc58a91 3452 }
1da177e4
LT		 3453 }
3454out:
99f89551
EB		 3455 put_task_struct(leader);
3456out_no_task:
1da177e4
LT		 3457 return retval;
3458}
6e66b52b
EB		 3459
3460static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3461{
3462 struct inode *inode = dentry->d_inode;
99f89551 3463 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3464 generic_fillattr(inode, stat);
3465
99f89551 3466 if (p) {
99f89551 3467 stat->nlink += get_nr_threads(p);
99f89551 3468 put_task_struct(p);
6e66b52b
EB		 3469 }
3470
3471 return 0;
3472}
28a6d671 3473
c5ef1c42 3474static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3475 .lookup = proc_task_lookup,
3476 .getattr = proc_task_getattr,
3477 .setattr = proc_setattr,
3478};
3479
00977a59 3480static const struct file_operations proc_task_operations = {
28a6d671
EB		 3481 .read = generic_read_dir,
3482 .readdir = proc_task_readdir,
6038f373 3483 .llseek = default_llseek,
28a6d671 3484};
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