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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
4614a696
JS		 1410static ssize_t comm_write(struct file *file, const char __user *buf,
1411 size_t count, loff_t *offset)
1412{
1413 struct inode *inode = file->f_path.dentry->d_inode;
1414 struct task_struct *p;
1415 char buffer[TASK_COMM_LEN];
1416
1417 memset(buffer, 0, sizeof(buffer));
1418 if (count > sizeof(buffer) - 1)
1419 count = sizeof(buffer) - 1;
1420 if (copy_from_user(buffer, buf, count))
1421 return -EFAULT;
1422
1423 p = get_proc_task(inode);
1424 if (!p)
1425 return -ESRCH;
1426
1427 if (same_thread_group(current, p))
1428 set_task_comm(p, buffer);
1429 else
1430 count = -EINVAL;
1431
1432 put_task_struct(p);
1433
1434 return count;
1435}
1436
1437static int comm_show(struct seq_file *m, void *v)
1438{
1439 struct inode *inode = m->private;
1440 struct task_struct *p;
1441
1442 p = get_proc_task(inode);
1443 if (!p)
1444 return -ESRCH;
1445
1446 task_lock(p);
1447 seq_printf(m, "%s\n", p->comm);
1448 task_unlock(p);
1449
1450 put_task_struct(p);
1451
1452 return 0;
1453}
1454
1455static int comm_open(struct inode *inode, struct file *filp)
1456{
1457 int ret;
1458
1459 ret = single_open(filp, comm_show, NULL);
1460 if (!ret) {
1461 struct seq_file *m = filp->private_data;
1462
1463 m->private = inode;
1464 }
1465 return ret;
1466}
1467
1468static const struct file_operations proc_pid_set_comm_operations = {
1469 .open = comm_open,
1470 .read = seq_read,
1471 .write = comm_write,
1472 .llseek = seq_lseek,
1473 .release = single_release,
1474};
1475
925d1c40
MH		 1476/*
1477 * We added or removed a vma mapping the executable. The vmas are only mapped
1478 * during exec and are not mapped with the mmap system call.
1479 * Callers must hold down_write() on the mm's mmap_sem for these
1480 */
1481void added_exe_file_vma(struct mm_struct *mm)
1482{
1483 mm->num_exe_file_vmas++;
1484}
1485
1486void removed_exe_file_vma(struct mm_struct *mm)
1487{
1488 mm->num_exe_file_vmas--;
1489 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){
1490 fput(mm->exe_file);
1491 mm->exe_file = NULL;
1492 }
1493
1494}
1495
1496void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file)
1497{
1498 if (new_exe_file)
1499 get_file(new_exe_file);
1500 if (mm->exe_file)
1501 fput(mm->exe_file);
1502 mm->exe_file = new_exe_file;
1503 mm->num_exe_file_vmas = 0;
1504}
1505
1506struct file *get_mm_exe_file(struct mm_struct *mm)
1507{
1508 struct file *exe_file;
1509
1510 /* We need mmap_sem to protect against races with removal of
1511 * VM_EXECUTABLE vmas */
1512 down_read(&mm->mmap_sem);
1513 exe_file = mm->exe_file;
1514 if (exe_file)
1515 get_file(exe_file);
1516 up_read(&mm->mmap_sem);
1517 return exe_file;
1518}
1519
1520void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm)
1521{
1522 /* It's safe to write the exe_file pointer without exe_file_lock because
1523 * this is called during fork when the task is not yet in /proc */
1524 newmm->exe_file = get_mm_exe_file(oldmm);
1525}
1526
1527static int proc_exe_link(struct inode *inode, struct path *exe_path)
1528{
1529 struct task_struct *task;
1530 struct mm_struct *mm;
1531 struct file *exe_file;
1532
1533 task = get_proc_task(inode);
1534 if (!task)
1535 return -ENOENT;
1536 mm = get_task_mm(task);
1537 put_task_struct(task);
1538 if (!mm)
1539 return -ENOENT;
1540 exe_file = get_mm_exe_file(mm);
1541 mmput(mm);
1542 if (exe_file) {
1543 *exe_path = exe_file->f_path;
1544 path_get(&exe_file->f_path);
1545 fput(exe_file);
1546 return 0;
1547 } else
1548 return -ENOENT;
1549}
1550
008b150a 1551static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1552{
1553 struct inode *inode = dentry->d_inode;
1554 int error = -EACCES;
1555
1556 /* We don't need a base pointer in the /proc filesystem */
1d957f9b 1557 path_put(&nd->path);
1da177e4 1558
778c1144
EB		 1559 /* Are we allowed to snoop on the tasks file descriptors? */
1560 if (!proc_fd_access_allowed(inode))
1da177e4 1561 goto out;
1da177e4 1562
3dcd25f3 1563 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
1da177e4 1564out:
008b150a 1565 return ERR_PTR(error);
1da177e4
LT		 1566}
1567
3dcd25f3 1568static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1569{
e12ba74d 1570 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1571 char *pathname;
1da177e4
LT		 1572 int len;
1573
1574 if (!tmp)
1575 return -ENOMEM;
0c28f287 1576
8df9d1a4 1577 pathname = d_path_with_unreachable(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1578 len = PTR_ERR(pathname);
1579 if (IS_ERR(pathname))
1da177e4 1580 goto out;
3dcd25f3 1581 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1582
1583 if (len > buflen)
1584 len = buflen;
3dcd25f3 1585 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1586 len = -EFAULT;
1587 out:
1588 free_page((unsigned long)tmp);
1589 return len;
1590}
1591
1592static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1593{
1594 int error = -EACCES;
1595 struct inode *inode = dentry->d_inode;
3dcd25f3 1596 struct path path;
1da177e4 1597
778c1144
EB		 1598 /* Are we allowed to snoop on the tasks file descriptors? */
1599 if (!proc_fd_access_allowed(inode))
1da177e4 1600 goto out;
1da177e4 1601
3dcd25f3 1602 error = PROC_I(inode)->op.proc_get_link(inode, &path);
1da177e4
LT		 1603 if (error)
1604 goto out;
1605
3dcd25f3
JB		 1606 error = do_proc_readlink(&path, buffer, buflen);
1607 path_put(&path);
1da177e4 1608out:
1da177e4
LT		 1609 return error;
1610}
1611
c5ef1c42 1612static const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1613 .readlink = proc_pid_readlink,
6d76fa58
LT		 1614 .follow_link = proc_pid_follow_link,
1615 .setattr = proc_setattr,
1da177e4
LT		 1616};
1617
28a6d671
EB		 1618
1619/* building an inode */
1620
1621static int task_dumpable(struct task_struct *task)
1da177e4 1622{
28a6d671
EB		 1623 int dumpable = 0;
1624 struct mm_struct *mm;
1da177e4 1625
28a6d671
EB		 1626 task_lock(task);
1627 mm = task->mm;
1628 if (mm)
6c5d5238 1629 dumpable = get_dumpable(mm);
28a6d671
EB		 1630 task_unlock(task);
1631 if(dumpable == 1)
1632 return 1;
1633 return 0;
1634}
1da177e4 1635
1da177e4 1636
61a28784 1637static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1638{
1639 struct inode * inode;
1640 struct proc_inode *ei;
c69e8d9c 1641 const struct cred *cred;
1da177e4 1642
28a6d671 1643 /* We need a new inode */
1da177e4 1644
28a6d671
EB		 1645 inode = new_inode(sb);
1646 if (!inode)
1647 goto out;
1648
1649 /* Common stuff */
1650 ei = PROC_I(inode);
85fe4025 1651 inode->i_ino = get_next_ino();
28a6d671 1652 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
28a6d671
EB		 1653 inode->i_op = &proc_def_inode_operations;
1654
1655 /*
1656 * grab the reference to task.
1657 */
1a657f78 1658 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1659 if (!ei->pid)
1660 goto out_unlock;
1661
28a6d671 1662 if (task_dumpable(task)) {
c69e8d9c
DH		 1663 rcu_read_lock();
1664 cred = __task_cred(task);
1665 inode->i_uid = cred->euid;
1666 inode->i_gid = cred->egid;
1667 rcu_read_unlock();
1da177e4 1668 }
28a6d671
EB		 1669 security_task_to_inode(task, inode);
1670
1da177e4 1671out:
28a6d671
EB		 1672 return inode;
1673
1674out_unlock:
1675 iput(inode);
1676 return NULL;
1da177e4
LT		 1677}
1678
28a6d671 1679static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1680{
1da177e4 1681 struct inode *inode = dentry->d_inode;
28a6d671 1682 struct task_struct *task;
c69e8d9c
DH		 1683 const struct cred *cred;
1684
28a6d671 1685 generic_fillattr(inode, stat);
1da177e4 1686
28a6d671
EB		 1687 rcu_read_lock();
1688 stat->uid = 0;
1689 stat->gid = 0;
1690 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1691 if (task) {
1692 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1693 task_dumpable(task)) {
c69e8d9c
DH		 1694 cred = __task_cred(task);
1695 stat->uid = cred->euid;
1696 stat->gid = cred->egid;
1da177e4
LT		 1697 }
1698 }
28a6d671 1699 rcu_read_unlock();
d6e71144 1700 return 0;
1da177e4
LT		 1701}
1702
1da177e4
LT		 1703/* dentry stuff */
1704
1705/*
1706 * Exceptional case: normally we are not allowed to unhash a busy
1707 * directory. In this case, however, we can do it - no aliasing problems
1708 * due to the way we treat inodes.
1709 *
1710 * Rewrite the inode's ownerships here because the owning task may have
1711 * performed a setuid(), etc.
99f89551
EB		 1712 *
1713 * Before the /proc/pid/status file was created the only way to read
1714 * the effective uid of a /process was to stat /proc/pid. Reading
1715 * /proc/pid/status is slow enough that procps and other packages
1716 * kept stating /proc/pid. To keep the rules in /proc simple I have
1717 * made this apply to all per process world readable and executable
1718 * directories.
1da177e4
LT		 1719 */
1720static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1721{
1722 struct inode *inode = dentry->d_inode;
99f89551 1723 struct task_struct *task = get_proc_task(inode);
c69e8d9c
DH		 1724 const struct cred *cred;
1725
99f89551
EB		 1726 if (task) {
1727 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1728 task_dumpable(task)) {
c69e8d9c
DH		 1729 rcu_read_lock();
1730 cred = __task_cred(task);
1731 inode->i_uid = cred->euid;
1732 inode->i_gid = cred->egid;
1733 rcu_read_unlock();
1da177e4
LT		 1734 } else {
1735 inode->i_uid = 0;
1736 inode->i_gid = 0;
1737 }
9ee8ab9f 1738 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1739 security_task_to_inode(task, inode);
99f89551 1740 put_task_struct(task);
1da177e4
LT		 1741 return 1;
1742 }
1743 d_drop(dentry);
1744 return 0;
1745}
1746
28a6d671 1747static int pid_delete_dentry(struct dentry * dentry)
99f89551 1748{
28a6d671
EB		 1749 /* Is the task we represent dead?
1750 * If so, then don't put the dentry on the lru list,
1751 * kill it immediately.
1752 */
1753 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1754}
1755
d72f71eb 1756static const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1757{
1758 .d_revalidate = pid_revalidate,
1759 .d_delete = pid_delete_dentry,
1760};
1761
1762/* Lookups */
1763
c5141e6d
ED		 1764typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
1765 struct task_struct *, const void *);
61a28784 1766
1c0d04c9
EB		 1767/*
1768 * Fill a directory entry.
1769 *
1770 * If possible create the dcache entry and derive our inode number and
1771 * file type from dcache entry.
1772 *
1773 * Since all of the proc inode numbers are dynamically generated, the inode
1774 * numbers do not exist until the inode is cache. This means creating the
1775 * the dcache entry in readdir is necessary to keep the inode numbers
1776 * reported by readdir in sync with the inode numbers reported
1777 * by stat.
1778 */
61a28784
EB		 1779static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1780 char *name, int len,
c5141e6d 1781 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1782{
2fddfeef 1783 struct dentry *child, *dir = filp->f_path.dentry;
61a28784
EB		 1784 struct inode *inode;
1785 struct qstr qname;
1786 ino_t ino = 0;
1787 unsigned type = DT_UNKNOWN;
1788
1789 qname.name = name;
1790 qname.len = len;
1791 qname.hash = full_name_hash(name, len);
1792
1793 child = d_lookup(dir, &qname);
1794 if (!child) {
1795 struct dentry *new;
1796 new = d_alloc(dir, &qname);
1797 if (new) {
1798 child = instantiate(dir->d_inode, new, task, ptr);
1799 if (child)
1800 dput(new);
1801 else
1802 child = new;
1803 }
1804 }
1805 if (!child || IS_ERR(child) || !child->d_inode)
1806 goto end_instantiate;
1807 inode = child->d_inode;
1808 if (inode) {
1809 ino = inode->i_ino;
1810 type = inode->i_mode >> 12;
1811 }
1812 dput(child);
1813end_instantiate:
1814 if (!ino)
1815 ino = find_inode_number(dir, &qname);
1816 if (!ino)
1817 ino = 1;
1818 return filldir(dirent, name, len, filp->f_pos, ino, type);
1819}
1820
28a6d671
EB		 1821static unsigned name_to_int(struct dentry *dentry)
1822{
1823 const char *name = dentry->d_name.name;
1824 int len = dentry->d_name.len;
1825 unsigned n = 0;
1826
1827 if (len > 1 && *name == '0')
1828 goto out;
1829 while (len-- > 0) {
1830 unsigned c = *name++ - '0';
1831 if (c > 9)
1832 goto out;
1833 if (n >= (~0U-9)/10)
1834 goto out;
1835 n *= 10;
1836 n += c;
1837 }
1838 return n;
1839out:
1840 return ~0U;
1841}
1842
27932742
MS		 1843#define PROC_FDINFO_MAX 64
1844
3dcd25f3 1845static int proc_fd_info(struct inode *inode, struct path *path, char *info)
28a6d671
EB		 1846{
1847 struct task_struct *task = get_proc_task(inode);
1848 struct files_struct *files = NULL;
1849 struct file *file;
1850 int fd = proc_fd(inode);
99f89551 1851
99f89551 1852 if (task) {
28a6d671
EB		 1853 files = get_files_struct(task);
1854 put_task_struct(task);
1855 }
1856 if (files) {
1857 /*
1858 * We are not taking a ref to the file structure, so we must
1859 * hold ->file_lock.
1860 */
1861 spin_lock(&files->file_lock);
1862 file = fcheck_files(files, fd);
1863 if (file) {
3dcd25f3
JB		 1864 if (path) {
1865 *path = file->f_path;
1866 path_get(&file->f_path);
1867 }
27932742
MS		 1868 if (info)
1869 snprintf(info, PROC_FDINFO_MAX,
1870 "pos:\t%lli\n"
1871 "flags:\t0%o\n",
1872 (long long) file->f_pos,
1873 file->f_flags);
28a6d671
EB		 1874 spin_unlock(&files->file_lock);
1875 put_files_struct(files);
1876 return 0;
99f89551 1877 }
28a6d671
EB		 1878 spin_unlock(&files->file_lock);
1879 put_files_struct(files);
99f89551 1880 }
28a6d671 1881 return -ENOENT;
99f89551
EB		 1882}
1883
3dcd25f3 1884static int proc_fd_link(struct inode *inode, struct path *path)
27932742 1885{
3dcd25f3 1886 return proc_fd_info(inode, path, NULL);
27932742
MS		 1887}
1888
1da177e4
LT		 1889static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1890{
1891 struct inode *inode = dentry->d_inode;
99f89551 1892 struct task_struct *task = get_proc_task(inode);
aed7a6c4 1893 int fd = proc_fd(inode);
1da177e4 1894 struct files_struct *files;
c69e8d9c 1895 const struct cred *cred;
1da177e4 1896
99f89551
EB		 1897 if (task) {
1898 files = get_files_struct(task);
1899 if (files) {
1900 rcu_read_lock();
1901 if (fcheck_files(files, fd)) {
1902 rcu_read_unlock();
1903 put_files_struct(files);
1904 if (task_dumpable(task)) {
c69e8d9c
DH		 1905 rcu_read_lock();
1906 cred = __task_cred(task);
1907 inode->i_uid = cred->euid;
1908 inode->i_gid = cred->egid;
1909 rcu_read_unlock();
99f89551
EB		 1910 } else {
1911 inode->i_uid = 0;
1912 inode->i_gid = 0;
1913 }
9ee8ab9f 1914 inode->i_mode &= ~(S_ISUID | S_ISGID);
99f89551
EB		 1915 security_task_to_inode(task, inode);
1916 put_task_struct(task);
1917 return 1;
1918 }
b835996f 1919 rcu_read_unlock();
1da177e4 1920 put_files_struct(files);
1da177e4 1921 }
99f89551 1922 put_task_struct(task);
1da177e4
LT		 1923 }
1924 d_drop(dentry);
1925 return 0;
1926}
1927
d72f71eb 1928static const struct dentry_operations tid_fd_dentry_operations =
1da177e4
LT		 1929{
1930 .d_revalidate = tid_fd_revalidate,
1931 .d_delete = pid_delete_dentry,
1932};
1933
444ceed8 1934static struct dentry *proc_fd_instantiate(struct inode *dir,
c5141e6d 1935 struct dentry *dentry, struct task_struct *task, const void *ptr)
1da177e4 1936{
c5141e6d 1937 unsigned fd = *(const unsigned *)ptr;
444ceed8
EB		 1938 struct file *file;
1939 struct files_struct *files;
1940 struct inode *inode;
1941 struct proc_inode *ei;
1942 struct dentry *error = ERR_PTR(-ENOENT);
1da177e4 1943
61a28784 1944 inode = proc_pid_make_inode(dir->i_sb, task);
1da177e4
LT		 1945 if (!inode)
1946 goto out;
1947 ei = PROC_I(inode);
aed7a6c4 1948 ei->fd = fd;
1da177e4
LT		 1949 files = get_files_struct(task);
1950 if (!files)
444ceed8 1951 goto out_iput;
1da177e4 1952 inode->i_mode = S_IFLNK;
ca99c1da
DS		 1953
1954 /*
1955 * We are not taking a ref to the file structure, so we must
1956 * hold ->file_lock.
1957 */
1958 spin_lock(&files->file_lock);
1da177e4
LT		 1959 file = fcheck_files(files, fd);
1960 if (!file)
444ceed8 1961 goto out_unlock;
aeb5d727 1962 if (file->f_mode & FMODE_READ)
1da177e4 1963 inode->i_mode |= S_IRUSR | S_IXUSR;
aeb5d727 1964 if (file->f_mode & FMODE_WRITE)
1da177e4 1965 inode->i_mode |= S_IWUSR | S_IXUSR;
ca99c1da 1966 spin_unlock(&files->file_lock);
1da177e4 1967 put_files_struct(files);
444ceed8 1968
1da177e4
LT		 1969 inode->i_op = &proc_pid_link_inode_operations;
1970 inode->i_size = 64;
1971 ei->op.proc_get_link = proc_fd_link;
1972 dentry->d_op = &tid_fd_dentry_operations;
1973 d_add(dentry, inode);
cd6a3ce9
EB		 1974 /* Close the race of the process dying before we return the dentry */
1975 if (tid_fd_revalidate(dentry, NULL))
444ceed8 1976 error = NULL;
1da177e4 1977
444ceed8
EB		 1978 out:
1979 return error;
1980out_unlock:
ca99c1da 1981 spin_unlock(&files->file_lock);
1da177e4 1982 put_files_struct(files);
444ceed8 1983out_iput:
1da177e4 1984 iput(inode);
cd6a3ce9 1985 goto out;
1da177e4
LT		 1986}
1987
27932742
MS		 1988static struct dentry *proc_lookupfd_common(struct inode *dir,
1989 struct dentry *dentry,
1990 instantiate_t instantiate)
444ceed8
EB		 1991{
1992 struct task_struct *task = get_proc_task(dir);
1993 unsigned fd = name_to_int(dentry);
1994 struct dentry *result = ERR_PTR(-ENOENT);
1995
1996 if (!task)
1997 goto out_no_task;
1998 if (fd == ~0U)
1999 goto out;
2000
27932742 2001 result = instantiate(dir, dentry, task, &fd);
444ceed8
EB		 2002out:
2003 put_task_struct(task);
2004out_no_task:
2005 return result;
2006}
2007
27932742
MS		 2008static int proc_readfd_common(struct file * filp, void * dirent,
2009 filldir_t filldir, instantiate_t instantiate)
28a6d671 2010{
2fddfeef 2011 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2012 struct inode *inode = dentry->d_inode;
2013 struct task_struct *p = get_proc_task(inode);
457c2510 2014 unsigned int fd, ino;
28a6d671 2015 int retval;
28a6d671 2016 struct files_struct * files;
1da177e4 2017
28a6d671
EB		 2018 retval = -ENOENT;
2019 if (!p)
2020 goto out_no_task;
2021 retval = 0;
28a6d671
EB		 2022
2023 fd = filp->f_pos;
2024 switch (fd) {
2025 case 0:
2026 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
2027 goto out;
2028 filp->f_pos++;
2029 case 1:
2030 ino = parent_ino(dentry);
2031 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2032 goto out;
2033 filp->f_pos++;
2034 default:
2035 files = get_files_struct(p);
2036 if (!files)
2037 goto out;
2038 rcu_read_lock();
28a6d671 2039 for (fd = filp->f_pos-2;
9b4f526c 2040 fd < files_fdtable(files)->max_fds;
28a6d671 2041 fd++, filp->f_pos++) {
27932742
MS		 2042 char name[PROC_NUMBUF];
2043 int len;
28a6d671
EB		 2044
2045 if (!fcheck_files(files, fd))
2046 continue;
2047 rcu_read_unlock();
2048
27932742
MS		 2049 len = snprintf(name, sizeof(name), "%d", fd);
2050 if (proc_fill_cache(filp, dirent, filldir,
2051 name, len, instantiate,
2052 p, &fd) < 0) {
28a6d671
EB		 2053 rcu_read_lock();
2054 break;
2055 }
2056 rcu_read_lock();
2057 }
2058 rcu_read_unlock();
2059 put_files_struct(files);
2060 }
2061out:
2062 put_task_struct(p);
2063out_no_task:
2064 return retval;
2065}
2066
27932742
MS		 2067static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
2068 struct nameidata *nd)
2069{
2070 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
2071}
2072
2073static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
2074{
2075 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
2076}
2077
2078static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
2079 size_t len, loff_t *ppos)
2080{
2081 char tmp[PROC_FDINFO_MAX];
3dcd25f3 2082 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
27932742
MS		 2083 if (!err)
2084 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
2085 return err;
2086}
2087
2088static const struct file_operations proc_fdinfo_file_operations = {
87df8424 2089 .open = nonseekable_open,
27932742 2090 .read = proc_fdinfo_read,
6038f373 2091 .llseek = no_llseek,
27932742
MS		 2092};
2093
00977a59 2094static const struct file_operations proc_fd_operations = {
28a6d671
EB		 2095 .read = generic_read_dir,
2096 .readdir = proc_readfd,
6038f373 2097 .llseek = default_llseek,
1da177e4
LT		 2098};
2099
8948e11f
AD		 2100/*
2101 * /proc/pid/fd needs a special permission handler so that a process can still
2102 * access /proc/self/fd after it has executed a setuid().
2103 */
e6305c43 2104static int proc_fd_permission(struct inode *inode, int mask)
8948e11f
AD		 2105{
2106 int rv;
2107
2108 rv = generic_permission(inode, mask, NULL);
2109 if (rv == 0)
2110 return 0;
2111 if (task_pid(current) == proc_pid(inode))
2112 rv = 0;
2113 return rv;
2114}
2115
1da177e4
LT		 2116/*
2117 * proc directories can do almost nothing..
2118 */
c5ef1c42 2119static const struct inode_operations proc_fd_inode_operations = {
1da177e4 2120 .lookup = proc_lookupfd,
8948e11f 2121 .permission = proc_fd_permission,
6d76fa58 2122 .setattr = proc_setattr,
1da177e4
LT		 2123};
2124
27932742
MS		 2125static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2126 struct dentry *dentry, struct task_struct *task, const void *ptr)
2127{
2128 unsigned fd = *(unsigned *)ptr;
2129 struct inode *inode;
2130 struct proc_inode *ei;
2131 struct dentry *error = ERR_PTR(-ENOENT);
2132
2133 inode = proc_pid_make_inode(dir->i_sb, task);
2134 if (!inode)
2135 goto out;
2136 ei = PROC_I(inode);
2137 ei->fd = fd;
2138 inode->i_mode = S_IFREG | S_IRUSR;
2139 inode->i_fop = &proc_fdinfo_file_operations;
2140 dentry->d_op = &tid_fd_dentry_operations;
2141 d_add(dentry, inode);
2142 /* Close the race of the process dying before we return the dentry */
2143 if (tid_fd_revalidate(dentry, NULL))
2144 error = NULL;
2145
2146 out:
2147 return error;
2148}
2149
2150static struct dentry *proc_lookupfdinfo(struct inode *dir,
2151 struct dentry *dentry,
2152 struct nameidata *nd)
2153{
2154 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2155}
2156
2157static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2158{
2159 return proc_readfd_common(filp, dirent, filldir,
2160 proc_fdinfo_instantiate);
2161}
2162
2163static const struct file_operations proc_fdinfo_operations = {
2164 .read = generic_read_dir,
2165 .readdir = proc_readfdinfo,
6038f373 2166 .llseek = default_llseek,
27932742
MS		 2167};
2168
2169/*
2170 * proc directories can do almost nothing..
2171 */
2172static const struct inode_operations proc_fdinfo_inode_operations = {
2173 .lookup = proc_lookupfdinfo,
2174 .setattr = proc_setattr,
2175};
2176
2177
444ceed8 2178static struct dentry *proc_pident_instantiate(struct inode *dir,
c5141e6d 2179 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2180{
c5141e6d 2181 const struct pid_entry *p = ptr;
444ceed8
EB		 2182 struct inode *inode;
2183 struct proc_inode *ei;
bd6daba9 2184 struct dentry *error = ERR_PTR(-ENOENT);
444ceed8 2185
61a28784 2186 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2187 if (!inode)
2188 goto out;
2189
2190 ei = PROC_I(inode);
2191 inode->i_mode = p->mode;
2192 if (S_ISDIR(inode->i_mode))
2193 inode->i_nlink = 2; /* Use getattr to fix if necessary */
2194 if (p->iop)
2195 inode->i_op = p->iop;
2196 if (p->fop)
2197 inode->i_fop = p->fop;
2198 ei->op = p->op;
2199 dentry->d_op = &pid_dentry_operations;
2200 d_add(dentry, inode);
2201 /* Close the race of the process dying before we return the dentry */
2202 if (pid_revalidate(dentry, NULL))
2203 error = NULL;
2204out:
2205 return error;
2206}
2207
1da177e4
LT		 2208static struct dentry *proc_pident_lookup(struct inode *dir,
2209 struct dentry *dentry,
c5141e6d 2210 const struct pid_entry *ents,
7bcd6b0e 2211 unsigned int nents)
1da177e4 2212{
cd6a3ce9 2213 struct dentry *error;
99f89551 2214 struct task_struct *task = get_proc_task(dir);
c5141e6d 2215 const struct pid_entry *p, *last;
1da177e4 2216
cd6a3ce9 2217 error = ERR_PTR(-ENOENT);
1da177e4 2218
99f89551
EB		 2219 if (!task)
2220 goto out_no_task;
1da177e4 2221
20cdc894
EB		 2222 /*
2223 * Yes, it does not scale. And it should not. Don't add
2224 * new entries into /proc/<tgid>/ without very good reasons.
2225 */
7bcd6b0e
EB		 2226 last = &ents[nents - 1];
2227 for (p = ents; p <= last; p++) {
1da177e4
LT		 2228 if (p->len != dentry->d_name.len)
2229 continue;
2230 if (!memcmp(dentry->d_name.name, p->name, p->len))
2231 break;
2232 }
7bcd6b0e 2233 if (p > last)
1da177e4
LT		 2234 goto out;
2235
444ceed8 2236 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2237out:
99f89551
EB		 2238 put_task_struct(task);
2239out_no_task:
cd6a3ce9 2240 return error;
1da177e4
LT		 2241}
2242
c5141e6d
ED		 2243static int proc_pident_fill_cache(struct file *filp, void *dirent,
2244 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2245{
2246 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2247 proc_pident_instantiate, task, p);
2248}
2249
28a6d671
EB		 2250static int proc_pident_readdir(struct file *filp,
2251 void *dirent, filldir_t filldir,
c5141e6d 2252 const struct pid_entry *ents, unsigned int nents)
28a6d671
EB		 2253{
2254 int i;
2fddfeef 2255 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2256 struct inode *inode = dentry->d_inode;
2257 struct task_struct *task = get_proc_task(inode);
c5141e6d 2258 const struct pid_entry *p, *last;
28a6d671
EB		 2259 ino_t ino;
2260 int ret;
2261
2262 ret = -ENOENT;
2263 if (!task)
61a28784 2264 goto out_no_task;
28a6d671
EB		 2265
2266 ret = 0;
28a6d671
EB		 2267 i = filp->f_pos;
2268 switch (i) {
2269 case 0:
2270 ino = inode->i_ino;
2271 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2272 goto out;
2273 i++;
2274 filp->f_pos++;
2275 /* fall through */
2276 case 1:
2277 ino = parent_ino(dentry);
2278 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2279 goto out;
2280 i++;
2281 filp->f_pos++;
2282 /* fall through */
2283 default:
2284 i -= 2;
2285 if (i >= nents) {
2286 ret = 1;
2287 goto out;
2288 }
2289 p = ents + i;
7bcd6b0e
EB		 2290 last = &ents[nents - 1];
2291 while (p <= last) {
61a28784 2292 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
28a6d671
EB		 2293 goto out;
2294 filp->f_pos++;
2295 p++;
2296 }
2297 }
2298
2299 ret = 1;
2300out:
61a28784
EB		 2301 put_task_struct(task);
2302out_no_task:
28a6d671 2303 return ret;
1da177e4
LT		 2304}
2305
28a6d671
EB		 2306#ifdef CONFIG_SECURITY
2307static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2308 size_t count, loff_t *ppos)
2309{
2fddfeef 2310 struct inode * inode = file->f_path.dentry->d_inode;
04ff9708 2311 char *p = NULL;
28a6d671
EB		 2312 ssize_t length;
2313 struct task_struct *task = get_proc_task(inode);
2314
28a6d671 2315 if (!task)
04ff9708 2316 return -ESRCH;
28a6d671
EB		 2317
2318 length = security_getprocattr(task,
2fddfeef 2319 (char*)file->f_path.dentry->d_name.name,
04ff9708 2320 &p);
28a6d671 2321 put_task_struct(task);
04ff9708
AV		 2322 if (length > 0)
2323 length = simple_read_from_buffer(buf, count, ppos, p, length);
2324 kfree(p);
28a6d671 2325 return length;
1da177e4
LT		 2326}
2327
28a6d671
EB		 2328static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2329 size_t count, loff_t *ppos)
2330{
2fddfeef 2331 struct inode * inode = file->f_path.dentry->d_inode;
28a6d671
EB		 2332 char *page;
2333 ssize_t length;
2334 struct task_struct *task = get_proc_task(inode);
2335
2336 length = -ESRCH;
2337 if (!task)
2338 goto out_no_task;
2339 if (count > PAGE_SIZE)
2340 count = PAGE_SIZE;
2341
2342 /* No partial writes. */
2343 length = -EINVAL;
2344 if (*ppos != 0)
2345 goto out;
2346
2347 length = -ENOMEM;
e12ba74d 2348 page = (char*)__get_free_page(GFP_TEMPORARY);
28a6d671
EB		 2349 if (!page)
2350 goto out;
2351
2352 length = -EFAULT;
2353 if (copy_from_user(page, buf, count))
2354 goto out_free;
2355
107db7c7 2356 /* Guard against adverse ptrace interaction */
9b1bf12d 2357 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2358 if (length < 0)
2359 goto out_free;
2360
28a6d671 2361 length = security_setprocattr(task,
2fddfeef 2362 (char*)file->f_path.dentry->d_name.name,
28a6d671 2363 (void*)page, count);
9b1bf12d 2364 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671
EB		 2365out_free:
2366 free_page((unsigned long) page);
2367out:
2368 put_task_struct(task);
2369out_no_task:
2370 return length;
2371}
2372
00977a59 2373static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2374 .read = proc_pid_attr_read,
2375 .write = proc_pid_attr_write,
87df8424 2376 .llseek = generic_file_llseek,
28a6d671
EB		 2377};
2378
c5141e6d 2379static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2380 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2381 REG("prev", S_IRUGO, proc_pid_attr_operations),
2382 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2383 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2384 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2385 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2386};
2387
72d9dcfc 2388static int proc_attr_dir_readdir(struct file * filp,
28a6d671
EB		 2389 void * dirent, filldir_t filldir)
2390{
2391 return proc_pident_readdir(filp,dirent,filldir,
72d9dcfc 2392 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2393}
2394
00977a59 2395static const struct file_operations proc_attr_dir_operations = {
1da177e4 2396 .read = generic_read_dir,
72d9dcfc 2397 .readdir = proc_attr_dir_readdir,
6038f373 2398 .llseek = default_llseek,
1da177e4
LT		 2399};
2400
72d9dcfc 2401static struct dentry *proc_attr_dir_lookup(struct inode *dir,
28a6d671
EB		 2402 struct dentry *dentry, struct nameidata *nd)
2403{
7bcd6b0e
EB		 2404 return proc_pident_lookup(dir, dentry,
2405 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2406}
2407
c5ef1c42 2408static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2409 .lookup = proc_attr_dir_lookup,
99f89551 2410 .getattr = pid_getattr,
6d76fa58 2411 .setattr = proc_setattr,
1da177e4
LT		 2412};
2413
28a6d671
EB		 2414#endif
2415
698ba7b5 2416#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2417static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2418 size_t count, loff_t *ppos)
2419{
2420 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2421 struct mm_struct *mm;
2422 char buffer[PROC_NUMBUF];
2423 size_t len;
2424 int ret;
2425
2426 if (!task)
2427 return -ESRCH;
2428
2429 ret = 0;
2430 mm = get_task_mm(task);
2431 if (mm) {
2432 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2433 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2434 MMF_DUMP_FILTER_SHIFT));
2435 mmput(mm);
2436 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2437 }
2438
2439 put_task_struct(task);
2440
2441 return ret;
2442}
2443
2444static ssize_t proc_coredump_filter_write(struct file *file,
2445 const char __user *buf,
2446 size_t count,
2447 loff_t *ppos)
2448{
2449 struct task_struct *task;
2450 struct mm_struct *mm;
2451 char buffer[PROC_NUMBUF], *end;
2452 unsigned int val;
2453 int ret;
2454 int i;
2455 unsigned long mask;
2456
2457 ret = -EFAULT;
2458 memset(buffer, 0, sizeof(buffer));
2459 if (count > sizeof(buffer) - 1)
2460 count = sizeof(buffer) - 1;
2461 if (copy_from_user(buffer, buf, count))
2462 goto out_no_task;
2463
2464 ret = -EINVAL;
2465 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2466 if (*end == '\n')
2467 end++;
2468 if (end - buffer == 0)
2469 goto out_no_task;
2470
2471 ret = -ESRCH;
2472 task = get_proc_task(file->f_dentry->d_inode);
2473 if (!task)
2474 goto out_no_task;
2475
2476 ret = end - buffer;
2477 mm = get_task_mm(task);
2478 if (!mm)
2479 goto out_no_mm;
2480
2481 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2482 if (val & mask)
2483 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2484 else
2485 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2486 }
2487
2488 mmput(mm);
2489 out_no_mm:
2490 put_task_struct(task);
2491 out_no_task:
2492 return ret;
2493}
2494
2495static const struct file_operations proc_coredump_filter_operations = {
2496 .read = proc_coredump_filter_read,
2497 .write = proc_coredump_filter_write,
87df8424 2498 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2499};
2500#endif
2501
28a6d671
EB		 2502/*
2503 * /proc/self:
2504 */
2505static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2506 int buflen)
2507{
488e5bc4 2508 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2509 pid_t tgid = task_tgid_nr_ns(current, ns);
28a6d671 2510 char tmp[PROC_NUMBUF];
b55fcb22 2511 if (!tgid)
488e5bc4 2512 return -ENOENT;
b55fcb22 2513 sprintf(tmp, "%d", tgid);
28a6d671
EB		 2514 return vfs_readlink(dentry,buffer,buflen,tmp);
2515}
2516
2517static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2518{
488e5bc4 2519 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2520 pid_t tgid = task_tgid_nr_ns(current, ns);
7fee4868
AV		 2521 char *name = ERR_PTR(-ENOENT);
2522 if (tgid) {
2523 name = __getname();
2524 if (!name)
2525 name = ERR_PTR(-ENOMEM);
2526 else
2527 sprintf(name, "%d", tgid);
2528 }
2529 nd_set_link(nd, name);
2530 return NULL;
2531}
2532
2533static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2534 void *cookie)
2535{
2536 char *s = nd_get_link(nd);
2537 if (!IS_ERR(s))
2538 __putname(s);
28a6d671
EB		 2539}
2540
c5ef1c42 2541static const struct inode_operations proc_self_inode_operations = {
28a6d671
EB		 2542 .readlink = proc_self_readlink,
2543 .follow_link = proc_self_follow_link,
7fee4868 2544 .put_link = proc_self_put_link,
28a6d671
EB		 2545};
2546
801199ce
EB		 2547/*
2548 * proc base
2549 *
2550 * These are the directory entries in the root directory of /proc
2551 * that properly belong to the /proc filesystem, as they describe
2552 * describe something that is process related.
2553 */
c5141e6d 2554static const struct pid_entry proc_base_stuff[] = {
61a28784 2555 NOD("self", S_IFLNK|S_IRWXUGO,
801199ce 2556 &proc_self_inode_operations, NULL, {}),
801199ce
EB		 2557};
2558
2559/*
2560 * Exceptional case: normally we are not allowed to unhash a busy
2561 * directory. In this case, however, we can do it - no aliasing problems
2562 * due to the way we treat inodes.
2563 */
2564static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
2565{
2566 struct inode *inode = dentry->d_inode;
2567 struct task_struct *task = get_proc_task(inode);
2568 if (task) {
2569 put_task_struct(task);
2570 return 1;
2571 }
2572 d_drop(dentry);
2573 return 0;
2574}
2575
d72f71eb 2576static const struct dentry_operations proc_base_dentry_operations =
801199ce
EB		 2577{
2578 .d_revalidate = proc_base_revalidate,
2579 .d_delete = pid_delete_dentry,
2580};
2581
444ceed8 2582static struct dentry *proc_base_instantiate(struct inode *dir,
c5141e6d 2583 struct dentry *dentry, struct task_struct *task, const void *ptr)
801199ce 2584{
c5141e6d 2585 const struct pid_entry *p = ptr;
801199ce 2586 struct inode *inode;
801199ce 2587 struct proc_inode *ei;
73d36460 2588 struct dentry *error;
801199ce
EB		 2589
2590 /* Allocate the inode */
2591 error = ERR_PTR(-ENOMEM);
2592 inode = new_inode(dir->i_sb);
2593 if (!inode)
2594 goto out;
2595
2596 /* Initialize the inode */
2597 ei = PROC_I(inode);
85fe4025 2598 inode->i_ino = get_next_ino();
801199ce 2599 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
801199ce
EB		 2600
2601 /*
2602 * grab the reference to the task.
2603 */
1a657f78 2604 ei->pid = get_task_pid(task, PIDTYPE_PID);
801199ce
EB		 2605 if (!ei->pid)
2606 goto out_iput;
2607
801199ce
EB		 2608 inode->i_mode = p->mode;
2609 if (S_ISDIR(inode->i_mode))
2610 inode->i_nlink = 2;
2611 if (S_ISLNK(inode->i_mode))
2612 inode->i_size = 64;
2613 if (p->iop)
2614 inode->i_op = p->iop;
2615 if (p->fop)
2616 inode->i_fop = p->fop;
2617 ei->op = p->op;
2618 dentry->d_op = &proc_base_dentry_operations;
2619 d_add(dentry, inode);
2620 error = NULL;
2621out:
801199ce
EB		 2622 return error;
2623out_iput:
2624 iput(inode);
2625 goto out;
2626}
2627
444ceed8
EB		 2628static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2629{
2630 struct dentry *error;
2631 struct task_struct *task = get_proc_task(dir);
c5141e6d 2632 const struct pid_entry *p, *last;
444ceed8
EB		 2633
2634 error = ERR_PTR(-ENOENT);
2635
2636 if (!task)
2637 goto out_no_task;
2638
2639 /* Lookup the directory entry */
7bcd6b0e
EB		 2640 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2641 for (p = proc_base_stuff; p <= last; p++) {
444ceed8
EB		 2642 if (p->len != dentry->d_name.len)
2643 continue;
2644 if (!memcmp(dentry->d_name.name, p->name, p->len))
2645 break;
2646 }
7bcd6b0e 2647 if (p > last)
444ceed8
EB		 2648 goto out;
2649
2650 error = proc_base_instantiate(dir, dentry, task, p);
2651
2652out:
2653 put_task_struct(task);
2654out_no_task:
2655 return error;
2656}
2657
c5141e6d
ED		 2658static int proc_base_fill_cache(struct file *filp, void *dirent,
2659 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2660{
2661 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2662 proc_base_instantiate, task, p);
2663}
2664
aba76fdb 2665#ifdef CONFIG_TASK_IO_ACCOUNTING
297c5d92
AR		 2666static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2667{
940389b8 2668 struct task_io_accounting acct = task->ioac;
5995477a
AR		 2669 unsigned long flags;
2670
2671 if (whole && lock_task_sighand(task, &flags)) {
2672 struct task_struct *t = task;
2673
2674 task_io_accounting_add(&acct, &task->signal->ioac);
2675 while_each_thread(task, t)
2676 task_io_accounting_add(&acct, &t->ioac);
2677
2678 unlock_task_sighand(task, &flags);
297c5d92 2679 }
aba76fdb
AM		 2680 return sprintf(buffer,
2681 "rchar: %llu\n"
2682 "wchar: %llu\n"
2683 "syscr: %llu\n"
2684 "syscw: %llu\n"
2685 "read_bytes: %llu\n"
2686 "write_bytes: %llu\n"
2687 "cancelled_write_bytes: %llu\n",
7c44319d
AB		 2688 (unsigned long long)acct.rchar,
2689 (unsigned long long)acct.wchar,
2690 (unsigned long long)acct.syscr,
2691 (unsigned long long)acct.syscw,
2692 (unsigned long long)acct.read_bytes,
2693 (unsigned long long)acct.write_bytes,
2694 (unsigned long long)acct.cancelled_write_bytes);
297c5d92
AR		 2695}
2696
2697static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2698{
2699 return do_io_accounting(task, buffer, 0);
aba76fdb 2700}
297c5d92
AR		 2701
2702static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2703{
2704 return do_io_accounting(task, buffer, 1);
2705}
2706#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2707
47830723
KC		 2708static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2709 struct pid *pid, struct task_struct *task)
2710{
2711 seq_printf(m, "%08x\n", task->personality);
2712 return 0;
2713}
2714
28a6d671
EB		 2715/*
2716 * Thread groups
2717 */
00977a59 2718static const struct file_operations proc_task_operations;
c5ef1c42 2719static const struct inode_operations proc_task_inode_operations;
20cdc894 2720
c5141e6d 2721static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2722 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2723 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2724 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
b2211a36 2725#ifdef CONFIG_NET
631f9c18 2726 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 2727#endif
631f9c18
AD		 2728 REG("environ", S_IRUSR, proc_environ_operations),
2729 INF("auxv", S_IRUSR, proc_pid_auxv),
2730 ONE("status", S_IRUGO, proc_pid_status),
2731 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 2732 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 2733#ifdef CONFIG_SCHED_DEBUG
631f9c18 2734 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 2735#endif
4614a696 2736 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 2737#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 2738 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 2739#endif
631f9c18
AD		 2740 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2741 ONE("stat", S_IRUGO, proc_tgid_stat),
2742 ONE("statm", S_IRUGO, proc_pid_statm),
2743 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 2744#ifdef CONFIG_NUMA
631f9c18 2745 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 2746#endif
631f9c18
AD		 2747 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2748 LNK("cwd", proc_cwd_link),
2749 LNK("root", proc_root_link),
2750 LNK("exe", proc_exe_link),
2751 REG("mounts", S_IRUGO, proc_mounts_operations),
2752 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2753 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 2754#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 2755 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2756 REG("smaps", S_IRUGO, proc_smaps_operations),
2757 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 2758#endif
2759#ifdef CONFIG_SECURITY
631f9c18 2760 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 2761#endif
2762#ifdef CONFIG_KALLSYMS
631f9c18 2763 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 2764#endif
2ec220e2
KC		 2765#ifdef CONFIG_STACKTRACE
2766 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 2767#endif
2768#ifdef CONFIG_SCHEDSTATS
631f9c18 2769 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 2770#endif
9745512c 2771#ifdef CONFIG_LATENCYTOP
631f9c18 2772 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 2773#endif
8793d854 2774#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 2775 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 2776#endif
2777#ifdef CONFIG_CGROUPS
631f9c18 2778 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 2779#endif
631f9c18
AD		 2780 INF("oom_score", S_IRUGO, proc_oom_score),
2781 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 2782 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 2783#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 2784 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2785 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 2786#endif
f4f154fd 2787#ifdef CONFIG_FAULT_INJECTION
631f9c18 2788 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 2789#endif
698ba7b5 2790#ifdef CONFIG_ELF_CORE
631f9c18 2791 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 2792#endif
aba76fdb 2793#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 2794 INF("io", S_IRUGO, proc_tgid_io_accounting),
aba76fdb 2795#endif
28a6d671 2796};
1da177e4 2797
28a6d671 2798static int proc_tgid_base_readdir(struct file * filp,
1da177e4
LT		 2799 void * dirent, filldir_t filldir)
2800{
2801 return proc_pident_readdir(filp,dirent,filldir,
28a6d671 2802 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2803}
2804
00977a59 2805static const struct file_operations proc_tgid_base_operations = {
1da177e4 2806 .read = generic_read_dir,
28a6d671 2807 .readdir = proc_tgid_base_readdir,
6038f373 2808 .llseek = default_llseek,
1da177e4
LT		 2809};
2810
28a6d671 2811static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 2812 return proc_pident_lookup(dir, dentry,
2813 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2814}
2815
c5ef1c42 2816static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 2817 .lookup = proc_tgid_base_lookup,
99f89551 2818 .getattr = pid_getattr,
6d76fa58 2819 .setattr = proc_setattr,
1da177e4 2820};
1da177e4 2821
60347f67 2822static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 2823{
48e6484d 2824 struct dentry *dentry, *leader, *dir;
8578cea7 2825 char buf[PROC_NUMBUF];
48e6484d
EB		 2826 struct qstr name;
2827
2828 name.name = buf;
60347f67
PE		 2829 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2830 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 2831 if (dentry) {
29f12ca3 2832 shrink_dcache_parent(dentry);
48e6484d
EB		 2833 d_drop(dentry);
2834 dput(dentry);
2835 }
1da177e4 2836
48e6484d 2837 name.name = buf;
60347f67
PE		 2838 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2839 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 2840 if (!leader)
2841 goto out;
1da177e4 2842
48e6484d
EB		 2843 name.name = "task";
2844 name.len = strlen(name.name);
2845 dir = d_hash_and_lookup(leader, &name);
2846 if (!dir)
2847 goto out_put_leader;
2848
2849 name.name = buf;
60347f67 2850 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 2851 dentry = d_hash_and_lookup(dir, &name);
2852 if (dentry) {
2853 shrink_dcache_parent(dentry);
2854 d_drop(dentry);
2855 dput(dentry);
1da177e4 2856 }
48e6484d
EB		 2857
2858 dput(dir);
2859out_put_leader:
2860 dput(leader);
2861out:
2862 return;
1da177e4
LT		 2863}
2864
0895e91d
RD		 2865/**
2866 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2867 * @task: task that should be flushed.
2868 *
2869 * When flushing dentries from proc, one needs to flush them from global
60347f67 2870 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 2871 * in. This call is supposed to do all of this job.
2872 *
2873 * Looks in the dcache for
2874 * /proc/@pid
2875 * /proc/@tgid/task/@pid
2876 * if either directory is present flushes it and all of it'ts children
2877 * from the dcache.
2878 *
2879 * It is safe and reasonable to cache /proc entries for a task until
2880 * that task exits. After that they just clog up the dcache with
2881 * useless entries, possibly causing useful dcache entries to be
2882 * flushed instead. This routine is proved to flush those useless
2883 * dcache entries at process exit time.
2884 *
2885 * NOTE: This routine is just an optimization so it does not guarantee
2886 * that no dcache entries will exist at process exit time it
2887 * just makes it very unlikely that any will persist.
60347f67
PE		 2888 */
2889
2890void proc_flush_task(struct task_struct *task)
2891{
9fcc2d15 2892 int i;
9b4d1cbe 2893 struct pid *pid, *tgid;
130f77ec
PE		 2894 struct upid *upid;
2895
130f77ec 2896 pid = task_pid(task);
9b4d1cbe 2897 tgid = task_tgid(task);
130f77ec 2898
9fcc2d15 2899 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 2900 upid = &pid->numbers[i];
2901 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 2902 tgid->numbers[i].nr);
130f77ec 2903 }
6f4e6433
PE		 2904
2905 upid = &pid->numbers[pid->level];
2906 if (upid->nr == 1)
2907 pid_ns_release_proc(upid->ns);
60347f67
PE		 2908}
2909
9711ef99
AB		 2910static struct dentry *proc_pid_instantiate(struct inode *dir,
2911 struct dentry * dentry,
c5141e6d 2912 struct task_struct *task, const void *ptr)
444ceed8
EB		 2913{
2914 struct dentry *error = ERR_PTR(-ENOENT);
2915 struct inode *inode;
2916
61a28784 2917 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2918 if (!inode)
2919 goto out;
2920
2921 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2922 inode->i_op = &proc_tgid_base_inode_operations;
2923 inode->i_fop = &proc_tgid_base_operations;
2924 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 2925
2926 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
2927 ARRAY_SIZE(tgid_base_stuff));
444ceed8
EB		 2928
2929 dentry->d_op = &pid_dentry_operations;
2930
2931 d_add(dentry, inode);
2932 /* Close the race of the process dying before we return the dentry */
2933 if (pid_revalidate(dentry, NULL))
2934 error = NULL;
2935out:
2936 return error;
2937}
2938
1da177e4
LT		 2939struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2940{
73d36460 2941 struct dentry *result;
1da177e4 2942 struct task_struct *task;
1da177e4 2943 unsigned tgid;
b488893a 2944 struct pid_namespace *ns;
1da177e4 2945
801199ce
EB		 2946 result = proc_base_lookup(dir, dentry);
2947 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
2948 goto out;
2949
1da177e4
LT		 2950 tgid = name_to_int(dentry);
2951 if (tgid == ~0U)
2952 goto out;
2953
b488893a 2954 ns = dentry->d_sb->s_fs_info;
de758734 2955 rcu_read_lock();
b488893a 2956 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 2957 if (task)
2958 get_task_struct(task);
de758734 2959 rcu_read_unlock();
1da177e4
LT		 2960 if (!task)
2961 goto out;
2962
444ceed8 2963 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 2964 put_task_struct(task);
1da177e4 2965out:
cd6a3ce9 2966 return result;
1da177e4
LT		 2967}
2968
1da177e4 2969/*
0804ef4b 2970 * Find the first task with tgid >= tgid
0bc58a91 2971 *
1da177e4 2972 */
19fd4bb2
EB		 2973struct tgid_iter {
2974 unsigned int tgid;
0804ef4b 2975 struct task_struct *task;
19fd4bb2
EB		 2976};
2977static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
2978{
0804ef4b 2979 struct pid *pid;
1da177e4 2980
19fd4bb2
EB		 2981 if (iter.task)
2982 put_task_struct(iter.task);
454cc105 2983 rcu_read_lock();
0804ef4b 2984retry:
19fd4bb2
EB		 2985 iter.task = NULL;
2986 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 2987 if (pid) {
19fd4bb2
EB		 2988 iter.tgid = pid_nr_ns(pid, ns);
2989 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 2990 /* What we to know is if the pid we have find is the
2991 * pid of a thread_group_leader. Testing for task
2992 * being a thread_group_leader is the obvious thing
2993 * todo but there is a window when it fails, due to
2994 * the pid transfer logic in de_thread.
2995 *
2996 * So we perform the straight forward test of seeing
2997 * if the pid we have found is the pid of a thread
2998 * group leader, and don't worry if the task we have
2999 * found doesn't happen to be a thread group leader.
3000 * As we don't care in the case of readdir.
3001 */
19fd4bb2
EB		 3002 if (!iter.task || !has_group_leader_pid(iter.task)) {
3003 iter.tgid += 1;
0804ef4b 3004 goto retry;
19fd4bb2
EB		 3005 }
3006 get_task_struct(iter.task);
0bc58a91 3007 }
454cc105 3008 rcu_read_unlock();
19fd4bb2 3009 return iter;
1da177e4
LT		 3010}
3011
7bcd6b0e 3012#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
0804ef4b 3013
61a28784 3014static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
19fd4bb2 3015 struct tgid_iter iter)
61a28784
EB		 3016{
3017 char name[PROC_NUMBUF];
19fd4bb2 3018 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
61a28784 3019 return proc_fill_cache(filp, dirent, filldir, name, len,
19fd4bb2 3020 proc_pid_instantiate, iter.task, NULL);
61a28784
EB		 3021}
3022
1da177e4
LT		 3023/* for the /proc/ directory itself, after non-process stuff has been done */
3024int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3025{
1da177e4 3026 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2fddfeef 3027 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
19fd4bb2 3028 struct tgid_iter iter;
b488893a 3029 struct pid_namespace *ns;
1da177e4 3030
61a28784
EB		 3031 if (!reaper)
3032 goto out_no_task;
3033
7bcd6b0e 3034 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
c5141e6d 3035 const struct pid_entry *p = &proc_base_stuff[nr];
61a28784 3036 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
801199ce 3037 goto out;
1da177e4
LT		 3038 }
3039
b488893a 3040 ns = filp->f_dentry->d_sb->s_fs_info;
19fd4bb2
EB		 3041 iter.task = NULL;
3042 iter.tgid = filp->f_pos - TGID_OFFSET;
3043 for (iter = next_tgid(ns, iter);
3044 iter.task;
3045 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3046 filp->f_pos = iter.tgid + TGID_OFFSET;
3047 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
3048 put_task_struct(iter.task);
0804ef4b 3049 goto out;
1da177e4 3050 }
0bc58a91 3051 }
0804ef4b
EB		 3052 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3053out:
61a28784
EB		 3054 put_task_struct(reaper);
3055out_no_task:
0bc58a91
EB		 3056 return 0;
3057}
1da177e4 3058
28a6d671
EB		 3059/*
3060 * Tasks
3061 */
c5141e6d 3062static const struct pid_entry tid_base_stuff[] = {
631f9c18 3063 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3064 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
631f9c18
AD		 3065 REG("environ", S_IRUSR, proc_environ_operations),
3066 INF("auxv", S_IRUSR, proc_pid_auxv),
3067 ONE("status", S_IRUGO, proc_pid_status),
3068 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 3069 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3070#ifdef CONFIG_SCHED_DEBUG
631f9c18 3071 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3072#endif
4614a696 3073 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3074#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 3075 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 3076#endif
631f9c18
AD		 3077 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3078 ONE("stat", S_IRUGO, proc_tid_stat),
3079 ONE("statm", S_IRUGO, proc_pid_statm),
3080 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3081#ifdef CONFIG_NUMA
631f9c18 3082 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3083#endif
631f9c18
AD		 3084 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3085 LNK("cwd", proc_cwd_link),
3086 LNK("root", proc_root_link),
3087 LNK("exe", proc_exe_link),
3088 REG("mounts", S_IRUGO, proc_mounts_operations),
3089 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3090#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3091 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3092 REG("smaps", S_IRUGO, proc_smaps_operations),
3093 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 3094#endif
3095#ifdef CONFIG_SECURITY
631f9c18 3096 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3097#endif
3098#ifdef CONFIG_KALLSYMS
631f9c18 3099 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3100#endif
2ec220e2
KC		 3101#ifdef CONFIG_STACKTRACE
3102 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 3103#endif
3104#ifdef CONFIG_SCHEDSTATS
631f9c18 3105 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3106#endif
9745512c 3107#ifdef CONFIG_LATENCYTOP
631f9c18 3108 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3109#endif
8793d854 3110#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3111 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3112#endif
3113#ifdef CONFIG_CGROUPS
631f9c18 3114 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3115#endif
631f9c18
AD		 3116 INF("oom_score", S_IRUGO, proc_oom_score),
3117 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3118 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3119#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 3120 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3121 REG("sessionid", S_IRUSR, proc_sessionid_operations),
28a6d671 3122#endif
f4f154fd 3123#ifdef CONFIG_FAULT_INJECTION
631f9c18 3124 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3125#endif
297c5d92 3126#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 3127 INF("io", S_IRUGO, proc_tid_io_accounting),
297c5d92 3128#endif
28a6d671
EB		 3129};
3130
3131static int proc_tid_base_readdir(struct file * filp,
3132 void * dirent, filldir_t filldir)
3133{
3134 return proc_pident_readdir(filp,dirent,filldir,
3135 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3136}
3137
3138static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3139 return proc_pident_lookup(dir, dentry,
3140 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3141}
3142
00977a59 3143static const struct file_operations proc_tid_base_operations = {
28a6d671
EB		 3144 .read = generic_read_dir,
3145 .readdir = proc_tid_base_readdir,
6038f373 3146 .llseek = default_llseek,
28a6d671
EB		 3147};
3148
c5ef1c42 3149static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3150 .lookup = proc_tid_base_lookup,
3151 .getattr = pid_getattr,
3152 .setattr = proc_setattr,
3153};
3154
444ceed8 3155static struct dentry *proc_task_instantiate(struct inode *dir,
c5141e6d 3156 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8
EB		 3157{
3158 struct dentry *error = ERR_PTR(-ENOENT);
3159 struct inode *inode;
61a28784 3160 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3161
3162 if (!inode)
3163 goto out;
3164 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3165 inode->i_op = &proc_tid_base_inode_operations;
3166 inode->i_fop = &proc_tid_base_operations;
3167 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 3168
3169 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
3170 ARRAY_SIZE(tid_base_stuff));
444ceed8
EB		 3171
3172 dentry->d_op = &pid_dentry_operations;
3173
3174 d_add(dentry, inode);
3175 /* Close the race of the process dying before we return the dentry */
3176 if (pid_revalidate(dentry, NULL))
3177 error = NULL;
3178out:
3179 return error;
3180}
3181
28a6d671
EB		 3182static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3183{
3184 struct dentry *result = ERR_PTR(-ENOENT);
3185 struct task_struct *task;
3186 struct task_struct *leader = get_proc_task(dir);
28a6d671 3187 unsigned tid;
b488893a 3188 struct pid_namespace *ns;
28a6d671
EB		 3189
3190 if (!leader)
3191 goto out_no_task;
3192
3193 tid = name_to_int(dentry);
3194 if (tid == ~0U)
3195 goto out;
3196
b488893a 3197 ns = dentry->d_sb->s_fs_info;
28a6d671 3198 rcu_read_lock();
b488893a 3199 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3200 if (task)
3201 get_task_struct(task);
3202 rcu_read_unlock();
3203 if (!task)
3204 goto out;
bac0abd6 3205 if (!same_thread_group(leader, task))
28a6d671
EB		 3206 goto out_drop_task;
3207
444ceed8 3208 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3209out_drop_task:
3210 put_task_struct(task);
3211out:
3212 put_task_struct(leader);
3213out_no_task:
3214 return result;
3215}
3216
0bc58a91
EB		 3217/*
3218 * Find the first tid of a thread group to return to user space.
3219 *
3220 * Usually this is just the thread group leader, but if the users
3221 * buffer was too small or there was a seek into the middle of the
3222 * directory we have more work todo.
3223 *
3224 * In the case of a short read we start with find_task_by_pid.
3225 *
3226 * In the case of a seek we start with the leader and walk nr
3227 * threads past it.
3228 */
cc288738 3229static struct task_struct *first_tid(struct task_struct *leader,
b488893a 3230 int tid, int nr, struct pid_namespace *ns)
0bc58a91 3231{
a872ff0c 3232 struct task_struct *pos;
1da177e4 3233
cc288738 3234 rcu_read_lock();
0bc58a91
EB		 3235 /* Attempt to start with the pid of a thread */
3236 if (tid && (nr > 0)) {
b488893a 3237 pos = find_task_by_pid_ns(tid, ns);
a872ff0c
ON		 3238 if (pos && (pos->group_leader == leader))
3239 goto found;
0bc58a91 3240 }
1da177e4 3241
0bc58a91 3242 /* If nr exceeds the number of threads there is nothing todo */
a872ff0c
ON		 3243 pos = NULL;
3244 if (nr && nr >= get_nr_threads(leader))
3245 goto out;
1da177e4 3246
a872ff0c
ON		 3247 /* If we haven't found our starting place yet start
3248 * with the leader and walk nr threads forward.
0bc58a91 3249 */
a872ff0c
ON		 3250 for (pos = leader; nr > 0; --nr) {
3251 pos = next_thread(pos);
3252 if (pos == leader) {
3253 pos = NULL;
3254 goto out;
3255 }
1da177e4 3256 }
a872ff0c
ON		 3257found:
3258 get_task_struct(pos);
3259out:
cc288738 3260 rcu_read_unlock();
0bc58a91
EB		 3261 return pos;
3262}
3263
3264/*
3265 * Find the next thread in the thread list.
3266 * Return NULL if there is an error or no next thread.
3267 *
3268 * The reference to the input task_struct is released.
3269 */
3270static struct task_struct *next_tid(struct task_struct *start)
3271{
c1df7fb8 3272 struct task_struct *pos = NULL;
cc288738 3273 rcu_read_lock();
c1df7fb8 3274 if (pid_alive(start)) {
0bc58a91 3275 pos = next_thread(start);
c1df7fb8
ON		 3276 if (thread_group_leader(pos))
3277 pos = NULL;
3278 else
3279 get_task_struct(pos);
3280 }
cc288738 3281 rcu_read_unlock();
0bc58a91
EB		 3282 put_task_struct(start);
3283 return pos;
1da177e4
LT		 3284}
3285
61a28784
EB		 3286static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3287 struct task_struct *task, int tid)
3288{
3289 char name[PROC_NUMBUF];
3290 int len = snprintf(name, sizeof(name), "%d", tid);
3291 return proc_fill_cache(filp, dirent, filldir, name, len,
3292 proc_task_instantiate, task, NULL);
3293}
3294
1da177e4
LT		 3295/* for the /proc/TGID/task/ directories */
3296static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3297{
2fddfeef 3298 struct dentry *dentry = filp->f_path.dentry;
1da177e4 3299 struct inode *inode = dentry->d_inode;
7d895244 3300 struct task_struct *leader = NULL;
0bc58a91 3301 struct task_struct *task;
1da177e4
LT		 3302 int retval = -ENOENT;
3303 ino_t ino;
0bc58a91 3304 int tid;
b488893a 3305 struct pid_namespace *ns;
1da177e4 3306
7d895244
GC		 3307 task = get_proc_task(inode);
3308 if (!task)
3309 goto out_no_task;
3310 rcu_read_lock();
3311 if (pid_alive(task)) {
3312 leader = task->group_leader;
3313 get_task_struct(leader);
3314 }
3315 rcu_read_unlock();
3316 put_task_struct(task);
99f89551
EB		 3317 if (!leader)
3318 goto out_no_task;
1da177e4
LT		 3319 retval = 0;
3320
ee568b25 3321 switch ((unsigned long)filp->f_pos) {
1da177e4
LT		 3322 case 0:
3323 ino = inode->i_ino;
ee6f779b 3324 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3325 goto out;
ee6f779b 3326 filp->f_pos++;
1da177e4
LT		 3327 /* fall through */
3328 case 1:
3329 ino = parent_ino(dentry);
ee6f779b 3330 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3331 goto out;
ee6f779b 3332 filp->f_pos++;
1da177e4
LT		 3333 /* fall through */
3334 }
3335
0bc58a91
EB		 3336 /* f_version caches the tgid value that the last readdir call couldn't
3337 * return. lseek aka telldir automagically resets f_version to 0.
3338 */
b488893a 3339 ns = filp->f_dentry->d_sb->s_fs_info;
2b47c361 3340 tid = (int)filp->f_version;
0bc58a91 3341 filp->f_version = 0;
ee6f779b 3342 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
0bc58a91 3343 task;
ee6f779b 3344 task = next_tid(task), filp->f_pos++) {
b488893a 3345 tid = task_pid_nr_ns(task, ns);
61a28784 3346 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
0bc58a91
EB		 3347 /* returning this tgid failed, save it as the first
3348 * pid for the next readir call */
2b47c361 3349 filp->f_version = (u64)tid;
0bc58a91 3350 put_task_struct(task);
1da177e4 3351 break;
0bc58a91 3352 }
1da177e4
LT		 3353 }
3354out:
99f89551
EB		 3355 put_task_struct(leader);
3356out_no_task:
1da177e4
LT		 3357 return retval;
3358}
6e66b52b
EB		 3359
3360static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3361{
3362 struct inode *inode = dentry->d_inode;
99f89551 3363 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3364 generic_fillattr(inode, stat);
3365
99f89551 3366 if (p) {
99f89551 3367 stat->nlink += get_nr_threads(p);
99f89551 3368 put_task_struct(p);
6e66b52b
EB		 3369 }
3370
3371 return 0;
3372}
28a6d671 3373
c5ef1c42 3374static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3375 .lookup = proc_task_lookup,
3376 .getattr = proc_task_getattr,
3377 .setattr = proc_setattr,
3378};
3379
00977a59 3380static const struct file_operations proc_task_operations = {
28a6d671
EB		 3381 .read = generic_read_dir,
3382 .readdir = proc_task_readdir,
6038f373 3383 .llseek = default_llseek,
28a6d671 3384};
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