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userns: Convert ext4 to user kuid/kgid where appropriate
[linux-2.6-block.git] / fs / proc / base.c
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1da177e4
LT		 1/*
2 * linux/fs/proc/base.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * proc base directory handling functions
7 *
8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
9 * Instead of using magical inumbers to determine the kind of object
10 * we allocate and fill in-core inodes upon lookup. They don't even
11 * go into icache. We cache the reference to task_struct upon lookup too.
12 * Eventually it should become a filesystem in its own. We don't use the
13 * rest of procfs anymore.
e070ad49
ML		 14 *
15 *
16 * Changelog:
17 * 17-Jan-2005
18 * Allan Bezerra
19 * Bruna Moreira <bruna.moreira@indt.org.br>
20 * Edjard Mota <edjard.mota@indt.org.br>
21 * Ilias Biris <ilias.biris@indt.org.br>
22 * Mauricio Lin <mauricio.lin@indt.org.br>
23 *
24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
25 *
26 * A new process specific entry (smaps) included in /proc. It shows the
27 * size of rss for each memory area. The maps entry lacks information
28 * about physical memory size (rss) for each mapped file, i.e.,
29 * rss information for executables and library files.
30 * This additional information is useful for any tools that need to know
31 * about physical memory consumption for a process specific library.
32 *
33 * Changelog:
34 * 21-Feb-2005
35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
36 * Pud inclusion in the page table walking.
37 *
38 * ChangeLog:
39 * 10-Mar-2005
40 * 10LE Instituto Nokia de Tecnologia - INdT:
41 * A better way to walks through the page table as suggested by Hugh Dickins.
42 *
43 * Simo Piiroinen <simo.piiroinen@nokia.com>:
44 * Smaps information related to shared, private, clean and dirty pages.
45 *
46 * Paul Mundt <paul.mundt@nokia.com>:
47 * Overall revision about smaps.
1da177e4
LT		 48 */
49
50#include <asm/uaccess.h>
51
1da177e4
LT		 52#include <linux/errno.h>
53#include <linux/time.h>
54#include <linux/proc_fs.h>
55#include <linux/stat.h>
5995477a 56#include <linux/task_io_accounting_ops.h>
1da177e4 57#include <linux/init.h>
16f7e0fe 58#include <linux/capability.h>
1da177e4 59#include <linux/file.h>
9f3acc31 60#include <linux/fdtable.h>
1da177e4
LT		 61#include <linux/string.h>
62#include <linux/seq_file.h>
63#include <linux/namei.h>
6b3286ed 64#include <linux/mnt_namespace.h>
1da177e4 65#include <linux/mm.h>
a63d83f4 66#include <linux/swap.h>
b835996f 67#include <linux/rcupdate.h>
1da177e4 68#include <linux/kallsyms.h>
2ec220e2 69#include <linux/stacktrace.h>
d85f50d5 70#include <linux/resource.h>
5096add8 71#include <linux/module.h>
1da177e4
LT		 72#include <linux/mount.h>
73#include <linux/security.h>
74#include <linux/ptrace.h>
0d094efe 75#include <linux/tracehook.h>
a424316c 76#include <linux/cgroup.h>
1da177e4
LT		 77#include <linux/cpuset.h>
78#include <linux/audit.h>
5addc5dd 79#include <linux/poll.h>
1651e14e 80#include <linux/nsproxy.h>
8ac773b4 81#include <linux/oom.h>
3cb4a0bb 82#include <linux/elf.h>
60347f67 83#include <linux/pid_namespace.h>
22d917d8 84#include <linux/user_namespace.h>
5ad4e53b 85#include <linux/fs_struct.h>
5a0e3ad6 86#include <linux/slab.h>
640708a2 87#include <linux/flex_array.h>
f133ecca
CM		 88#ifdef CONFIG_HARDWALL
89#include <asm/hardwall.h>
90#endif
43d2b113 91#include <trace/events/oom.h>
1da177e4
LT		 92#include "internal.h"
93
0f2fe20f
EB		 94/* NOTE:
95 * Implementing inode permission operations in /proc is almost
96 * certainly an error. Permission checks need to happen during
97 * each system call not at open time. The reason is that most of
98 * what we wish to check for permissions in /proc varies at runtime.
99 *
100 * The classic example of a problem is opening file descriptors
101 * in /proc for a task before it execs a suid executable.
102 */
103
1da177e4 104struct pid_entry {
1da177e4 105 char *name;
c5141e6d 106 int len;
d161a13f 107 umode_t mode;
c5ef1c42 108 const struct inode_operations *iop;
00977a59 109 const struct file_operations *fop;
20cdc894 110 union proc_op op;
1da177e4
LT		 111};
112
61a28784 113#define NOD(NAME, MODE, IOP, FOP, OP) { \
20cdc894 114 .name = (NAME), \
c5141e6d 115 .len = sizeof(NAME) - 1, \
20cdc894
EB		 116 .mode = MODE, \
117 .iop = IOP, \
118 .fop = FOP, \
119 .op = OP, \
120}
121
631f9c18
AD		 122#define DIR(NAME, MODE, iops, fops) \
123 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
124#define LNK(NAME, get_link) \
61a28784 125 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
20cdc894 126 &proc_pid_link_inode_operations, NULL, \
631f9c18
AD		 127 { .proc_get_link = get_link } )
128#define REG(NAME, MODE, fops) \
129 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
130#define INF(NAME, MODE, read) \
61a28784 131 NOD(NAME, (S_IFREG|(MODE)), \
20cdc894 132 NULL, &proc_info_file_operations, \
631f9c18
AD		 133 { .proc_read = read } )
134#define ONE(NAME, MODE, show) \
be614086
EB		 135 NOD(NAME, (S_IFREG|(MODE)), \
136 NULL, &proc_single_file_operations, \
631f9c18 137 { .proc_show = show } )
1da177e4 138
640708a2
PE		 139static int proc_fd_permission(struct inode *inode, int mask);
140
aed54175
VN		 141/*
142 * Count the number of hardlinks for the pid_entry table, excluding the .
143 * and .. links.
144 */
145static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
146 unsigned int n)
147{
148 unsigned int i;
149 unsigned int count;
150
151 count = 0;
152 for (i = 0; i < n; ++i) {
153 if (S_ISDIR(entries[i].mode))
154 ++count;
155 }
156
157 return count;
158}
159
f7ad3c6b 160static int get_task_root(struct task_struct *task, struct path *root)
1da177e4 161{
7c2c7d99
HD		 162 int result = -ENOENT;
163
0494f6ec 164 task_lock(task);
f7ad3c6b
MS		 165 if (task->fs) {
166 get_fs_root(task->fs, root);
7c2c7d99
HD		 167 result = 0;
168 }
0494f6ec 169 task_unlock(task);
7c2c7d99 170 return result;
0494f6ec
MS		 171}
172
7773fbc5 173static int proc_cwd_link(struct dentry *dentry, struct path *path)
0494f6ec 174{
7773fbc5 175 struct task_struct *task = get_proc_task(dentry->d_inode);
0494f6ec 176 int result = -ENOENT;
99f89551
EB		 177
178 if (task) {
f7ad3c6b
MS		 179 task_lock(task);
180 if (task->fs) {
181 get_fs_pwd(task->fs, path);
182 result = 0;
183 }
184 task_unlock(task);
99f89551
EB		 185 put_task_struct(task);
186 }
1da177e4
LT		 187 return result;
188}
189
7773fbc5 190static int proc_root_link(struct dentry *dentry, struct path *path)
1da177e4 191{
7773fbc5 192 struct task_struct *task = get_proc_task(dentry->d_inode);
1da177e4 193 int result = -ENOENT;
99f89551
EB		 194
195 if (task) {
f7ad3c6b 196 result = get_task_root(task, path);
99f89551
EB		 197 put_task_struct(task);
198 }
1da177e4
LT		 199 return result;
200}
201
e268337d
LT		 202struct mm_struct *mm_for_maps(struct task_struct *task)
203{
204 return mm_access(task, PTRACE_MODE_READ);
205}
206
1da177e4
LT		 207static int proc_pid_cmdline(struct task_struct *task, char * buffer)
208{
209 int res = 0;
210 unsigned int len;
211 struct mm_struct *mm = get_task_mm(task);
212 if (!mm)
213 goto out;
214 if (!mm->arg_end)
215 goto out_mm; /* Shh! No looking before we're done */
216
217 len = mm->arg_end - mm->arg_start;
218
219 if (len > PAGE_SIZE)
220 len = PAGE_SIZE;
221
222 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
223
224 // If the nul at the end of args has been overwritten, then
225 // assume application is using setproctitle(3).
226 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
227 len = strnlen(buffer, res);
228 if (len < res) {
229 res = len;
230 } else {
231 len = mm->env_end - mm->env_start;
232 if (len > PAGE_SIZE - res)
233 len = PAGE_SIZE - res;
234 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
235 res = strnlen(buffer, res);
236 }
237 }
238out_mm:
239 mmput(mm);
240out:
241 return res;
242}
243
244static int proc_pid_auxv(struct task_struct *task, char *buffer)
245{
2fadaef4
AV		 246 struct mm_struct *mm = mm_for_maps(task);
247 int res = PTR_ERR(mm);
248 if (mm && !IS_ERR(mm)) {
1da177e4 249 unsigned int nwords = 0;
dfe6b7d9 250 do {
1da177e4 251 nwords += 2;
dfe6b7d9 252 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1da177e4
LT		 253 res = nwords * sizeof(mm->saved_auxv[0]);
254 if (res > PAGE_SIZE)
255 res = PAGE_SIZE;
256 memcpy(buffer, mm->saved_auxv, res);
257 mmput(mm);
258 }
259 return res;
260}
261
262
263#ifdef CONFIG_KALLSYMS
264/*
265 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
266 * Returns the resolved symbol. If that fails, simply return the address.
267 */
268static int proc_pid_wchan(struct task_struct *task, char *buffer)
269{
ffb45122 270 unsigned long wchan;
9281acea 271 char symname[KSYM_NAME_LEN];
1da177e4
LT		 272
273 wchan = get_wchan(task);
274
9d65cb4a 275 if (lookup_symbol_name(wchan, symname) < 0)
f83ce3e6
JE		 276 if (!ptrace_may_access(task, PTRACE_MODE_READ))
277 return 0;
278 else
279 return sprintf(buffer, "%lu", wchan);
9d65cb4a
AD		 280 else
281 return sprintf(buffer, "%s", symname);
1da177e4
LT		 282}
283#endif /* CONFIG_KALLSYMS */
284
a9712bc1
AV		 285static int lock_trace(struct task_struct *task)
286{
287 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
288 if (err)
289 return err;
290 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
291 mutex_unlock(&task->signal->cred_guard_mutex);
292 return -EPERM;
293 }
294 return 0;
295}
296
297static void unlock_trace(struct task_struct *task)
298{
299 mutex_unlock(&task->signal->cred_guard_mutex);
300}
301
2ec220e2
KC		 302#ifdef CONFIG_STACKTRACE
303
304#define MAX_STACK_TRACE_DEPTH 64
305
306static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
307 struct pid *pid, struct task_struct *task)
308{
309 struct stack_trace trace;
310 unsigned long *entries;
a9712bc1 311 int err;
2ec220e2
KC		 312 int i;
313
314 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
315 if (!entries)
316 return -ENOMEM;
317
318 trace.nr_entries = 0;
319 trace.max_entries = MAX_STACK_TRACE_DEPTH;
320 trace.entries = entries;
321 trace.skip = 0;
2ec220e2 322
a9712bc1
AV		 323 err = lock_trace(task);
324 if (!err) {
325 save_stack_trace_tsk(task, &trace);
326
327 for (i = 0; i < trace.nr_entries; i++) {
b81a618d 328 seq_printf(m, "[<%pK>] %pS\n",
a9712bc1
AV		 329 (void *)entries[i], (void *)entries[i]);
330 }
331 unlock_trace(task);
2ec220e2
KC		 332 }
333 kfree(entries);
334
a9712bc1 335 return err;
2ec220e2
KC		 336}
337#endif
338
1da177e4
LT		 339#ifdef CONFIG_SCHEDSTATS
340/*
341 * Provides /proc/PID/schedstat
342 */
343static int proc_pid_schedstat(struct task_struct *task, char *buffer)
344{
172ba844 345 return sprintf(buffer, "%llu %llu %lu\n",
826e08b0
IM		 346 (unsigned long long)task->se.sum_exec_runtime,
347 (unsigned long long)task->sched_info.run_delay,
2d72376b 348 task->sched_info.pcount);
1da177e4
LT		 349}
350#endif
351
9745512c
AV		 352#ifdef CONFIG_LATENCYTOP
353static int lstats_show_proc(struct seq_file *m, void *v)
354{
355 int i;
13d77c37
HS		 356 struct inode *inode = m->private;
357 struct task_struct *task = get_proc_task(inode);
9745512c 358
13d77c37
HS		 359 if (!task)
360 return -ESRCH;
361 seq_puts(m, "Latency Top version : v0.1\n");
9745512c 362 for (i = 0; i < 32; i++) {
34e49d4f
JP		 363 struct latency_record *lr = &task->latency_record[i];
364 if (lr->backtrace[0]) {
9745512c 365 int q;
34e49d4f
JP		 366 seq_printf(m, "%i %li %li",
367 lr->count, lr->time, lr->max);
9745512c 368 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
34e49d4f
JP		 369 unsigned long bt = lr->backtrace[q];
370 if (!bt)
9745512c 371 break;
34e49d4f 372 if (bt == ULONG_MAX)
9745512c 373 break;
34e49d4f 374 seq_printf(m, " %ps", (void *)bt);
9745512c 375 }
9d6de12f 376 seq_putc(m, '\n');
9745512c
AV		 377 }
378
379 }
13d77c37 380 put_task_struct(task);
9745512c
AV		 381 return 0;
382}
383
384static int lstats_open(struct inode *inode, struct file *file)
385{
13d77c37 386 return single_open(file, lstats_show_proc, inode);
d6643d12
HS		 387}
388
9745512c
AV		 389static ssize_t lstats_write(struct file *file, const char __user *buf,
390 size_t count, loff_t *offs)
391{
13d77c37 392 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
9745512c 393
13d77c37
HS		 394 if (!task)
395 return -ESRCH;
9745512c 396 clear_all_latency_tracing(task);
13d77c37 397 put_task_struct(task);
9745512c
AV		 398
399 return count;
400}
401
402static const struct file_operations proc_lstats_operations = {
403 .open = lstats_open,
404 .read = seq_read,
405 .write = lstats_write,
406 .llseek = seq_lseek,
13d77c37 407 .release = single_release,
9745512c
AV		 408};
409
410#endif
411
1da177e4
LT		 412static int proc_oom_score(struct task_struct *task, char *buffer)
413{
b95c35e7 414 unsigned long points = 0;
1da177e4 415
19c5d45a 416 read_lock(&tasklist_lock);
b95c35e7 417 if (pid_alive(task))
a63d83f4
DR		 418 points = oom_badness(task, NULL, NULL,
419 totalram_pages + total_swap_pages);
19c5d45a 420 read_unlock(&tasklist_lock);
1da177e4
LT		 421 return sprintf(buffer, "%lu\n", points);
422}
423
d85f50d5
NH		 424struct limit_names {
425 char *name;
426 char *unit;
427};
428
429static const struct limit_names lnames[RLIM_NLIMITS] = {
cff4edb5 430 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
d85f50d5
NH		 431 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
432 [RLIMIT_DATA] = {"Max data size", "bytes"},
433 [RLIMIT_STACK] = {"Max stack size", "bytes"},
434 [RLIMIT_CORE] = {"Max core file size", "bytes"},
435 [RLIMIT_RSS] = {"Max resident set", "bytes"},
436 [RLIMIT_NPROC] = {"Max processes", "processes"},
437 [RLIMIT_NOFILE] = {"Max open files", "files"},
438 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
439 [RLIMIT_AS] = {"Max address space", "bytes"},
440 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
441 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
442 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
443 [RLIMIT_NICE] = {"Max nice priority", NULL},
444 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
8808117c 445 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
d85f50d5
NH		 446};
447
448/* Display limits for a process */
449static int proc_pid_limits(struct task_struct *task, char *buffer)
450{
451 unsigned int i;
452 int count = 0;
453 unsigned long flags;
454 char *bufptr = buffer;
455
456 struct rlimit rlim[RLIM_NLIMITS];
457
a6bebbc8 458 if (!lock_task_sighand(task, &flags))
d85f50d5 459 return 0;
d85f50d5
NH		 460 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
461 unlock_task_sighand(task, &flags);
d85f50d5
NH		 462
463 /*
464 * print the file header
465 */
466 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
467 "Limit", "Soft Limit", "Hard Limit", "Units");
468
469 for (i = 0; i < RLIM_NLIMITS; i++) {
470 if (rlim[i].rlim_cur == RLIM_INFINITY)
471 count += sprintf(&bufptr[count], "%-25s %-20s ",
472 lnames[i].name, "unlimited");
473 else
474 count += sprintf(&bufptr[count], "%-25s %-20lu ",
475 lnames[i].name, rlim[i].rlim_cur);
476
477 if (rlim[i].rlim_max == RLIM_INFINITY)
478 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
479 else
480 count += sprintf(&bufptr[count], "%-20lu ",
481 rlim[i].rlim_max);
482
483 if (lnames[i].unit)
484 count += sprintf(&bufptr[count], "%-10s\n",
485 lnames[i].unit);
486 else
487 count += sprintf(&bufptr[count], "\n");
488 }
489
490 return count;
491}
492
ebcb6734
RM		 493#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
494static int proc_pid_syscall(struct task_struct *task, char *buffer)
495{
496 long nr;
497 unsigned long args[6], sp, pc;
a9712bc1
AV		 498 int res = lock_trace(task);
499 if (res)
500 return res;
ebcb6734
RM		 501
502 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
a9712bc1
AV		 503 res = sprintf(buffer, "running\n");
504 else if (nr < 0)
505 res = sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
506 else
507 res = sprintf(buffer,
ebcb6734
RM		 508 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
509 nr,
510 args[0], args[1], args[2], args[3], args[4], args[5],
511 sp, pc);
a9712bc1
AV		 512 unlock_trace(task);
513 return res;
ebcb6734
RM		 514}
515#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
516
1da177e4
LT		 517/************************************************************************/
518/* Here the fs part begins */
519/************************************************************************/
520
521/* permission checks */
778c1144 522static int proc_fd_access_allowed(struct inode *inode)
1da177e4 523{
778c1144
EB		 524 struct task_struct *task;
525 int allowed = 0;
df26c40e
EB		 526 /* Allow access to a task's file descriptors if it is us or we
527 * may use ptrace attach to the process and find out that
528 * information.
778c1144
EB		 529 */
530 task = get_proc_task(inode);
df26c40e 531 if (task) {
006ebb40 532 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
778c1144 533 put_task_struct(task);
df26c40e 534 }
778c1144 535 return allowed;
1da177e4
LT		 536}
537
6b4e306a 538int proc_setattr(struct dentry *dentry, struct iattr *attr)
6d76fa58
LT		 539{
540 int error;
541 struct inode *inode = dentry->d_inode;
542
543 if (attr->ia_valid & ATTR_MODE)
544 return -EPERM;
545
546 error = inode_change_ok(inode, attr);
1025774c
CH		 547 if (error)
548 return error;
549
550 if ((attr->ia_valid & ATTR_SIZE) &&
551 attr->ia_size != i_size_read(inode)) {
552 error = vmtruncate(inode, attr->ia_size);
553 if (error)
554 return error;
555 }
556
557 setattr_copy(inode, attr);
558 mark_inode_dirty(inode);
559 return 0;
6d76fa58
LT		 560}
561
0499680a
VK		 562/*
563 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
564 * or euid/egid (for hide_pid_min=2)?
565 */
566static bool has_pid_permissions(struct pid_namespace *pid,
567 struct task_struct *task,
568 int hide_pid_min)
569{
570 if (pid->hide_pid < hide_pid_min)
571 return true;
572 if (in_group_p(pid->pid_gid))
573 return true;
574 return ptrace_may_access(task, PTRACE_MODE_READ);
575}
576
577
578static int proc_pid_permission(struct inode *inode, int mask)
579{
580 struct pid_namespace *pid = inode->i_sb->s_fs_info;
581 struct task_struct *task;
582 bool has_perms;
583
584 task = get_proc_task(inode);
a2ef990a
XF		 585 if (!task)
586 return -ESRCH;
0499680a
VK		 587 has_perms = has_pid_permissions(pid, task, 1);
588 put_task_struct(task);
589
590 if (!has_perms) {
591 if (pid->hide_pid == 2) {
592 /*
593 * Let's make getdents(), stat(), and open()
594 * consistent with each other. If a process
595 * may not stat() a file, it shouldn't be seen
596 * in procfs at all.
597 */
598 return -ENOENT;
599 }
600
601 return -EPERM;
602 }
603 return generic_permission(inode, mask);
604}
605
606
607
c5ef1c42 608static const struct inode_operations proc_def_inode_operations = {
6d76fa58
LT		 609 .setattr = proc_setattr,
610};
611
1da177e4
LT		 612#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
613
614static ssize_t proc_info_read(struct file * file, char __user * buf,
615 size_t count, loff_t *ppos)
616{
2fddfeef 617 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 618 unsigned long page;
619 ssize_t length;
99f89551
EB		 620 struct task_struct *task = get_proc_task(inode);
621
622 length = -ESRCH;
623 if (!task)
624 goto out_no_task;
1da177e4
LT		 625
626 if (count > PROC_BLOCK_SIZE)
627 count = PROC_BLOCK_SIZE;
99f89551
EB		 628
629 length = -ENOMEM;
e12ba74d 630 if (!(page = __get_free_page(GFP_TEMPORARY)))
99f89551 631 goto out;
1da177e4
LT		 632
633 length = PROC_I(inode)->op.proc_read(task, (char*)page);
634
635 if (length >= 0)
636 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
637 free_page(page);
99f89551
EB		 638out:
639 put_task_struct(task);
640out_no_task:
1da177e4
LT		 641 return length;
642}
643
00977a59 644static const struct file_operations proc_info_file_operations = {
1da177e4 645 .read = proc_info_read,
87df8424 646 .llseek = generic_file_llseek,
1da177e4
LT		 647};
648
be614086
EB		 649static int proc_single_show(struct seq_file *m, void *v)
650{
651 struct inode *inode = m->private;
652 struct pid_namespace *ns;
653 struct pid *pid;
654 struct task_struct *task;
655 int ret;
656
657 ns = inode->i_sb->s_fs_info;
658 pid = proc_pid(inode);
659 task = get_pid_task(pid, PIDTYPE_PID);
660 if (!task)
661 return -ESRCH;
662
663 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
664
665 put_task_struct(task);
666 return ret;
667}
668
669static int proc_single_open(struct inode *inode, struct file *filp)
670{
c6a34058 671 return single_open(filp, proc_single_show, inode);
be614086
EB		 672}
673
674static const struct file_operations proc_single_file_operations = {
675 .open = proc_single_open,
676 .read = seq_read,
677 .llseek = seq_lseek,
678 .release = single_release,
679};
680
1da177e4
LT		 681static int mem_open(struct inode* inode, struct file* file)
682{
e268337d
LT		 683 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
684 struct mm_struct *mm;
685
686 if (!task)
687 return -ESRCH;
688
689 mm = mm_access(task, PTRACE_MODE_ATTACH);
690 put_task_struct(task);
691
692 if (IS_ERR(mm))
693 return PTR_ERR(mm);
694
6d08f2c7
ON		 695 if (mm) {
696 /* ensure this mm_struct can't be freed */
697 atomic_inc(&mm->mm_count);
698 /* but do not pin its memory */
699 mmput(mm);
700 }
701
4a3956c7
KH		 702 /* OK to pass negative loff_t, we can catch out-of-range */
703 file->f_mode |= FMODE_UNSIGNED_OFFSET;
e268337d
LT		 704 file->private_data = mm;
705
1da177e4
LT		 706 return 0;
707}
708
572d34b9
ON		 709static ssize_t mem_rw(struct file *file, char __user *buf,
710 size_t count, loff_t *ppos, int write)
1da177e4 711{
e268337d 712 struct mm_struct *mm = file->private_data;
572d34b9
ON		 713 unsigned long addr = *ppos;
714 ssize_t copied;
1da177e4 715 char *page;
1da177e4 716
e268337d
LT		 717 if (!mm)
718 return 0;
99f89551 719
30cd8903
KM		 720 page = (char *)__get_free_page(GFP_TEMPORARY);
721 if (!page)
e268337d 722 return -ENOMEM;
1da177e4 723
f7ca54f4 724 copied = 0;
6d08f2c7
ON		 725 if (!atomic_inc_not_zero(&mm->mm_users))
726 goto free;
727
1da177e4 728 while (count > 0) {
572d34b9 729 int this_len = min_t(int, count, PAGE_SIZE);
1da177e4 730
572d34b9 731 if (write && copy_from_user(page, buf, this_len)) {
1da177e4
LT		 732 copied = -EFAULT;
733 break;
734 }
572d34b9
ON		 735
736 this_len = access_remote_vm(mm, addr, page, this_len, write);
737 if (!this_len) {
1da177e4
LT		 738 if (!copied)
739 copied = -EIO;
740 break;
741 }
572d34b9
ON		 742
743 if (!write && copy_to_user(buf, page, this_len)) {
744 copied = -EFAULT;
745 break;
746 }
747
748 buf += this_len;
749 addr += this_len;
750 copied += this_len;
751 count -= this_len;
1da177e4 752 }
572d34b9 753 *ppos = addr;
30cd8903 754
6d08f2c7
ON		 755 mmput(mm);
756free:
30cd8903 757 free_page((unsigned long) page);
1da177e4
LT		 758 return copied;
759}
1da177e4 760
572d34b9
ON		 761static ssize_t mem_read(struct file *file, char __user *buf,
762 size_t count, loff_t *ppos)
763{
764 return mem_rw(file, buf, count, ppos, 0);
765}
766
767static ssize_t mem_write(struct file *file, const char __user *buf,
768 size_t count, loff_t *ppos)
769{
770 return mem_rw(file, (char __user*)buf, count, ppos, 1);
771}
772
85863e47 773loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 774{
775 switch (orig) {
776 case 0:
777 file->f_pos = offset;
778 break;
779 case 1:
780 file->f_pos += offset;
781 break;
782 default:
783 return -EINVAL;
784 }
785 force_successful_syscall_return();
786 return file->f_pos;
787}
788
e268337d
LT		 789static int mem_release(struct inode *inode, struct file *file)
790{
791 struct mm_struct *mm = file->private_data;
71879d3c 792 if (mm)
6d08f2c7 793 mmdrop(mm);
e268337d
LT		 794 return 0;
795}
796
00977a59 797static const struct file_operations proc_mem_operations = {
1da177e4
LT		 798 .llseek = mem_lseek,
799 .read = mem_read,
800 .write = mem_write,
801 .open = mem_open,
e268337d 802 .release = mem_release,
1da177e4
LT		 803};
804
315e28c8
JP		 805static ssize_t environ_read(struct file *file, char __user *buf,
806 size_t count, loff_t *ppos)
807{
808 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
809 char *page;
810 unsigned long src = *ppos;
811 int ret = -ESRCH;
812 struct mm_struct *mm;
813
814 if (!task)
815 goto out_no_task;
816
315e28c8
JP		 817 ret = -ENOMEM;
818 page = (char *)__get_free_page(GFP_TEMPORARY);
819 if (!page)
820 goto out;
821
315e28c8 822
d6f64b89
AV		 823 mm = mm_for_maps(task);
824 ret = PTR_ERR(mm);
825 if (!mm || IS_ERR(mm))
315e28c8
JP		 826 goto out_free;
827
d6f64b89 828 ret = 0;
315e28c8
JP		 829 while (count > 0) {
830 int this_len, retval, max_len;
831
832 this_len = mm->env_end - (mm->env_start + src);
833
834 if (this_len <= 0)
835 break;
836
837 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
838 this_len = (this_len > max_len) ? max_len : this_len;
839
840 retval = access_process_vm(task, (mm->env_start + src),
841 page, this_len, 0);
842
843 if (retval <= 0) {
844 ret = retval;
845 break;
846 }
847
848 if (copy_to_user(buf, page, retval)) {
849 ret = -EFAULT;
850 break;
851 }
852
853 ret += retval;
854 src += retval;
855 buf += retval;
856 count -= retval;
857 }
858 *ppos = src;
859
860 mmput(mm);
861out_free:
862 free_page((unsigned long) page);
863out:
864 put_task_struct(task);
865out_no_task:
866 return ret;
867}
868
869static const struct file_operations proc_environ_operations = {
870 .read = environ_read,
87df8424 871 .llseek = generic_file_llseek,
315e28c8
JP		 872};
873
1da177e4
LT		 874static ssize_t oom_adjust_read(struct file *file, char __user *buf,
875 size_t count, loff_t *ppos)
876{
2fddfeef 877 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
8578cea7 878 char buffer[PROC_NUMBUF];
1da177e4 879 size_t len;
28b83c51
KM		 880 int oom_adjust = OOM_DISABLE;
881 unsigned long flags;
1da177e4 882
99f89551
EB		 883 if (!task)
884 return -ESRCH;
28b83c51
KM		 885
886 if (lock_task_sighand(task, &flags)) {
887 oom_adjust = task->signal->oom_adj;
888 unlock_task_sighand(task, &flags);
889 }
890
99f89551
EB		 891 put_task_struct(task);
892
8578cea7 893 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
0c28f287
AM		 894
895 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1da177e4
LT		 896}
897
898static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
899 size_t count, loff_t *ppos)
900{
99f89551 901 struct task_struct *task;
5d863b89 902 char buffer[PROC_NUMBUF];
0a8cb8e3 903 int oom_adjust;
28b83c51 904 unsigned long flags;
5d863b89 905 int err;
1da177e4 906
8578cea7
EB		 907 memset(buffer, 0, sizeof(buffer));
908 if (count > sizeof(buffer) - 1)
909 count = sizeof(buffer) - 1;
723548bf
DR		 910 if (copy_from_user(buffer, buf, count)) {
911 err = -EFAULT;
912 goto out;
913 }
5d863b89 914
0a8cb8e3 915 err = kstrtoint(strstrip(buffer), 0, &oom_adjust);
5d863b89 916 if (err)
723548bf 917 goto out;
8ac773b4 918 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
723548bf
DR		 919 oom_adjust != OOM_DISABLE) {
920 err = -EINVAL;
921 goto out;
922 }
5d863b89 923
2fddfeef 924 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 925 if (!task) {
926 err = -ESRCH;
927 goto out;
928 }
d19d5476
DR		 929
930 task_lock(task);
931 if (!task->mm) {
932 err = -EINVAL;
933 goto err_task_lock;
934 }
935
28b83c51 936 if (!lock_task_sighand(task, &flags)) {
723548bf 937 err = -ESRCH;
d19d5476 938 goto err_task_lock;
28b83c51
KM		 939 }
940
941 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 942 err = -EACCES;
943 goto err_sighand;
8fb4fc68 944 }
28b83c51 945
51b1bd2a
DR		 946 /*
947 * Warn that /proc/pid/oom_adj is deprecated, see
948 * Documentation/feature-removal-schedule.txt.
949 */
c2142704 950 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
be8f684d
DR		 951 current->comm, task_pid_nr(current), task_pid_nr(task),
952 task_pid_nr(task));
28b83c51 953 task->signal->oom_adj = oom_adjust;
a63d83f4
DR		 954 /*
955 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
956 * value is always attainable.
957 */
958 if (task->signal->oom_adj == OOM_ADJUST_MAX)
959 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
960 else
961 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
962 -OOM_DISABLE;
43d2b113 963 trace_oom_score_adj_update(task);
723548bf 964err_sighand:
28b83c51 965 unlock_task_sighand(task, &flags);
d19d5476
DR		 966err_task_lock:
967 task_unlock(task);
99f89551 968 put_task_struct(task);
723548bf
DR		 969out:
970 return err < 0 ? err : count;
1da177e4
LT		 971}
972
00977a59 973static const struct file_operations proc_oom_adjust_operations = {
1da177e4
LT		 974 .read = oom_adjust_read,
975 .write = oom_adjust_write,
87df8424 976 .llseek = generic_file_llseek,
1da177e4
LT		 977};
978
a63d83f4
DR		 979static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
980 size_t count, loff_t *ppos)
981{
982 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
983 char buffer[PROC_NUMBUF];
984 int oom_score_adj = OOM_SCORE_ADJ_MIN;
985 unsigned long flags;
986 size_t len;
987
988 if (!task)
989 return -ESRCH;
990 if (lock_task_sighand(task, &flags)) {
991 oom_score_adj = task->signal->oom_score_adj;
992 unlock_task_sighand(task, &flags);
993 }
994 put_task_struct(task);
995 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
996 return simple_read_from_buffer(buf, count, ppos, buffer, len);
997}
998
999static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1000 size_t count, loff_t *ppos)
1001{
1002 struct task_struct *task;
1003 char buffer[PROC_NUMBUF];
1004 unsigned long flags;
0a8cb8e3 1005 int oom_score_adj;
a63d83f4
DR		 1006 int err;
1007
1008 memset(buffer, 0, sizeof(buffer));
1009 if (count > sizeof(buffer) - 1)
1010 count = sizeof(buffer) - 1;
723548bf
DR		 1011 if (copy_from_user(buffer, buf, count)) {
1012 err = -EFAULT;
1013 goto out;
1014 }
a63d83f4 1015
0a8cb8e3 1016 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
a63d83f4 1017 if (err)
723548bf 1018 goto out;
a63d83f4 1019 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
723548bf
DR		 1020 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1021 err = -EINVAL;
1022 goto out;
1023 }
a63d83f4
DR		 1024
1025 task = get_proc_task(file->f_path.dentry->d_inode);
723548bf
DR		 1026 if (!task) {
1027 err = -ESRCH;
1028 goto out;
1029 }
d19d5476
DR		 1030
1031 task_lock(task);
1032 if (!task->mm) {
1033 err = -EINVAL;
1034 goto err_task_lock;
1035 }
1036
a63d83f4 1037 if (!lock_task_sighand(task, &flags)) {
723548bf 1038 err = -ESRCH;
d19d5476 1039 goto err_task_lock;
a63d83f4 1040 }
d19d5476 1041
dabb16f6 1042 if (oom_score_adj < task->signal->oom_score_adj_min &&
a63d83f4 1043 !capable(CAP_SYS_RESOURCE)) {
723548bf
DR		 1044 err = -EACCES;
1045 goto err_sighand;
a63d83f4
DR		 1046 }
1047
1048 task->signal->oom_score_adj = oom_score_adj;
dabb16f6
MSB		 1049 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1050 task->signal->oom_score_adj_min = oom_score_adj;
43d2b113 1051 trace_oom_score_adj_update(task);
a63d83f4
DR		 1052 /*
1053 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1054 * always attainable.
1055 */
1056 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1057 task->signal->oom_adj = OOM_DISABLE;
1058 else
1059 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1060 OOM_SCORE_ADJ_MAX;
723548bf 1061err_sighand:
a63d83f4 1062 unlock_task_sighand(task, &flags);
d19d5476
DR		 1063err_task_lock:
1064 task_unlock(task);
a63d83f4 1065 put_task_struct(task);
723548bf
DR		 1066out:
1067 return err < 0 ? err : count;
a63d83f4
DR		 1068}
1069
1070static const struct file_operations proc_oom_score_adj_operations = {
1071 .read = oom_score_adj_read,
1072 .write = oom_score_adj_write,
6038f373 1073 .llseek = default_llseek,
a63d83f4
DR		 1074};
1075
1da177e4
LT		 1076#ifdef CONFIG_AUDITSYSCALL
1077#define TMPBUFLEN 21
1078static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1079 size_t count, loff_t *ppos)
1080{
2fddfeef 1081 struct inode * inode = file->f_path.dentry->d_inode;
99f89551 1082 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1083 ssize_t length;
1084 char tmpbuf[TMPBUFLEN];
1085
99f89551
EB		 1086 if (!task)
1087 return -ESRCH;
1da177e4 1088 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
0c11b942 1089 audit_get_loginuid(task));
99f89551 1090 put_task_struct(task);
1da177e4
LT		 1091 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1092}
1093
1094static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1095 size_t count, loff_t *ppos)
1096{
2fddfeef 1097 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1098 char *page, *tmp;
1099 ssize_t length;
1da177e4
LT		 1100 uid_t loginuid;
1101
7dc52157
PM		 1102 rcu_read_lock();
1103 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1104 rcu_read_unlock();
1da177e4 1105 return -EPERM;
7dc52157
PM		 1106 }
1107 rcu_read_unlock();
1da177e4 1108
e0182909
AV		 1109 if (count >= PAGE_SIZE)
1110 count = PAGE_SIZE - 1;
1da177e4
LT		 1111
1112 if (*ppos != 0) {
1113 /* No partial writes. */
1114 return -EINVAL;
1115 }
e12ba74d 1116 page = (char*)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 1117 if (!page)
1118 return -ENOMEM;
1119 length = -EFAULT;
1120 if (copy_from_user(page, buf, count))
1121 goto out_free_page;
1122
e0182909 1123 page[count] = '\0';
1da177e4
LT		 1124 loginuid = simple_strtoul(page, &tmp, 10);
1125 if (tmp == page) {
1126 length = -EINVAL;
1127 goto out_free_page;
1128
1129 }
0a300be6 1130 length = audit_set_loginuid(loginuid);
1da177e4
LT		 1131 if (likely(length == 0))
1132 length = count;
1133
1134out_free_page:
1135 free_page((unsigned long) page);
1136 return length;
1137}
1138
00977a59 1139static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1140 .read = proc_loginuid_read,
1141 .write = proc_loginuid_write,
87df8424 1142 .llseek = generic_file_llseek,
1da177e4 1143};
1e0bd755
EP		 1144
1145static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1146 size_t count, loff_t *ppos)
1147{
1148 struct inode * inode = file->f_path.dentry->d_inode;
1149 struct task_struct *task = get_proc_task(inode);
1150 ssize_t length;
1151 char tmpbuf[TMPBUFLEN];
1152
1153 if (!task)
1154 return -ESRCH;
1155 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1156 audit_get_sessionid(task));
1157 put_task_struct(task);
1158 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1159}
1160
1161static const struct file_operations proc_sessionid_operations = {
1162 .read = proc_sessionid_read,
87df8424 1163 .llseek = generic_file_llseek,
1e0bd755 1164};
1da177e4
LT		 1165#endif
1166
f4f154fd
AM		 1167#ifdef CONFIG_FAULT_INJECTION
1168static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1169 size_t count, loff_t *ppos)
1170{
1171 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1172 char buffer[PROC_NUMBUF];
1173 size_t len;
1174 int make_it_fail;
f4f154fd
AM		 1175
1176 if (!task)
1177 return -ESRCH;
1178 make_it_fail = task->make_it_fail;
1179 put_task_struct(task);
1180
1181 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1182
1183 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1184}
1185
1186static ssize_t proc_fault_inject_write(struct file * file,
1187 const char __user * buf, size_t count, loff_t *ppos)
1188{
1189 struct task_struct *task;
1190 char buffer[PROC_NUMBUF], *end;
1191 int make_it_fail;
1192
1193 if (!capable(CAP_SYS_RESOURCE))
1194 return -EPERM;
1195 memset(buffer, 0, sizeof(buffer));
1196 if (count > sizeof(buffer) - 1)
1197 count = sizeof(buffer) - 1;
1198 if (copy_from_user(buffer, buf, count))
1199 return -EFAULT;
cba8aafe
VL		 1200 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1201 if (*end)
1202 return -EINVAL;
f4f154fd
AM		 1203 task = get_proc_task(file->f_dentry->d_inode);
1204 if (!task)
1205 return -ESRCH;
1206 task->make_it_fail = make_it_fail;
1207 put_task_struct(task);
cba8aafe
VL		 1208
1209 return count;
f4f154fd
AM		 1210}
1211
00977a59 1212static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1213 .read = proc_fault_inject_read,
1214 .write = proc_fault_inject_write,
87df8424 1215 .llseek = generic_file_llseek,
f4f154fd
AM		 1216};
1217#endif
1218
9745512c 1219
43ae34cb
IM		 1220#ifdef CONFIG_SCHED_DEBUG
1221/*
1222 * Print out various scheduling related per-task fields:
1223 */
1224static int sched_show(struct seq_file *m, void *v)
1225{
1226 struct inode *inode = m->private;
1227 struct task_struct *p;
1228
43ae34cb
IM		 1229 p = get_proc_task(inode);
1230 if (!p)
1231 return -ESRCH;
1232 proc_sched_show_task(p, m);
1233
1234 put_task_struct(p);
1235
1236 return 0;
1237}
1238
1239static ssize_t
1240sched_write(struct file *file, const char __user *buf,
1241 size_t count, loff_t *offset)
1242{
1243 struct inode *inode = file->f_path.dentry->d_inode;
1244 struct task_struct *p;
1245
43ae34cb
IM		 1246 p = get_proc_task(inode);
1247 if (!p)
1248 return -ESRCH;
1249 proc_sched_set_task(p);
1250
1251 put_task_struct(p);
1252
1253 return count;
1254}
1255
1256static int sched_open(struct inode *inode, struct file *filp)
1257{
c6a34058 1258 return single_open(filp, sched_show, inode);
43ae34cb
IM		 1259}
1260
1261static const struct file_operations proc_pid_sched_operations = {
1262 .open = sched_open,
1263 .read = seq_read,
1264 .write = sched_write,
1265 .llseek = seq_lseek,
5ea473a1 1266 .release = single_release,
43ae34cb
IM		 1267};
1268
1269#endif
1270
5091faa4
MG		 1271#ifdef CONFIG_SCHED_AUTOGROUP
1272/*
1273 * Print out autogroup related information:
1274 */
1275static int sched_autogroup_show(struct seq_file *m, void *v)
1276{
1277 struct inode *inode = m->private;
1278 struct task_struct *p;
1279
1280 p = get_proc_task(inode);
1281 if (!p)
1282 return -ESRCH;
1283 proc_sched_autogroup_show_task(p, m);
1284
1285 put_task_struct(p);
1286
1287 return 0;
1288}
1289
1290static ssize_t
1291sched_autogroup_write(struct file *file, const char __user *buf,
1292 size_t count, loff_t *offset)
1293{
1294 struct inode *inode = file->f_path.dentry->d_inode;
1295 struct task_struct *p;
1296 char buffer[PROC_NUMBUF];
0a8cb8e3 1297 int nice;
5091faa4
MG		 1298 int err;
1299
1300 memset(buffer, 0, sizeof(buffer));
1301 if (count > sizeof(buffer) - 1)
1302 count = sizeof(buffer) - 1;
1303 if (copy_from_user(buffer, buf, count))
1304 return -EFAULT;
1305
0a8cb8e3
AD		 1306 err = kstrtoint(strstrip(buffer), 0, &nice);
1307 if (err < 0)
1308 return err;
5091faa4
MG		 1309
1310 p = get_proc_task(inode);
1311 if (!p)
1312 return -ESRCH;
1313
2e5b5b3a 1314 err = proc_sched_autogroup_set_nice(p, nice);
5091faa4
MG		 1315 if (err)
1316 count = err;
1317
1318 put_task_struct(p);
1319
1320 return count;
1321}
1322
1323static int sched_autogroup_open(struct inode *inode, struct file *filp)
1324{
1325 int ret;
1326
1327 ret = single_open(filp, sched_autogroup_show, NULL);
1328 if (!ret) {
1329 struct seq_file *m = filp->private_data;
1330
1331 m->private = inode;
1332 }
1333 return ret;
1334}
1335
1336static const struct file_operations proc_pid_sched_autogroup_operations = {
1337 .open = sched_autogroup_open,
1338 .read = seq_read,
1339 .write = sched_autogroup_write,
1340 .llseek = seq_lseek,
1341 .release = single_release,
1342};
1343
1344#endif /* CONFIG_SCHED_AUTOGROUP */
1345
4614a696 1346static ssize_t comm_write(struct file *file, const char __user *buf,
1347 size_t count, loff_t *offset)
1348{
1349 struct inode *inode = file->f_path.dentry->d_inode;
1350 struct task_struct *p;
1351 char buffer[TASK_COMM_LEN];
1352
1353 memset(buffer, 0, sizeof(buffer));
1354 if (count > sizeof(buffer) - 1)
1355 count = sizeof(buffer) - 1;
1356 if (copy_from_user(buffer, buf, count))
1357 return -EFAULT;
1358
1359 p = get_proc_task(inode);
1360 if (!p)
1361 return -ESRCH;
1362
1363 if (same_thread_group(current, p))
1364 set_task_comm(p, buffer);
1365 else
1366 count = -EINVAL;
1367
1368 put_task_struct(p);
1369
1370 return count;
1371}
1372
1373static int comm_show(struct seq_file *m, void *v)
1374{
1375 struct inode *inode = m->private;
1376 struct task_struct *p;
1377
1378 p = get_proc_task(inode);
1379 if (!p)
1380 return -ESRCH;
1381
1382 task_lock(p);
1383 seq_printf(m, "%s\n", p->comm);
1384 task_unlock(p);
1385
1386 put_task_struct(p);
1387
1388 return 0;
1389}
1390
1391static int comm_open(struct inode *inode, struct file *filp)
1392{
c6a34058 1393 return single_open(filp, comm_show, inode);
4614a696 1394}
1395
1396static const struct file_operations proc_pid_set_comm_operations = {
1397 .open = comm_open,
1398 .read = seq_read,
1399 .write = comm_write,
1400 .llseek = seq_lseek,
1401 .release = single_release,
1402};
1403
7773fbc5 1404static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
925d1c40
MH		 1405{
1406 struct task_struct *task;
1407 struct mm_struct *mm;
1408 struct file *exe_file;
1409
7773fbc5 1410 task = get_proc_task(dentry->d_inode);
925d1c40
MH		 1411 if (!task)
1412 return -ENOENT;
1413 mm = get_task_mm(task);
1414 put_task_struct(task);
1415 if (!mm)
1416 return -ENOENT;
1417 exe_file = get_mm_exe_file(mm);
1418 mmput(mm);
1419 if (exe_file) {
1420 *exe_path = exe_file->f_path;
1421 path_get(&exe_file->f_path);
1422 fput(exe_file);
1423 return 0;
1424 } else
1425 return -ENOENT;
1426}
1427
008b150a 1428static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1429{
1430 struct inode *inode = dentry->d_inode;
1431 int error = -EACCES;
1432
1433 /* We don't need a base pointer in the /proc filesystem */
1d957f9b 1434 path_put(&nd->path);
1da177e4 1435
778c1144
EB		 1436 /* Are we allowed to snoop on the tasks file descriptors? */
1437 if (!proc_fd_access_allowed(inode))
1da177e4 1438 goto out;
1da177e4 1439
7773fbc5 1440 error = PROC_I(inode)->op.proc_get_link(dentry, &nd->path);
1da177e4 1441out:
008b150a 1442 return ERR_PTR(error);
1da177e4
LT		 1443}
1444
3dcd25f3 1445static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1446{
e12ba74d 1447 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1448 char *pathname;
1da177e4
LT		 1449 int len;
1450
1451 if (!tmp)
1452 return -ENOMEM;
0c28f287 1453
7b2a69ba 1454 pathname = d_path(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1455 len = PTR_ERR(pathname);
1456 if (IS_ERR(pathname))
1da177e4 1457 goto out;
3dcd25f3 1458 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1459
1460 if (len > buflen)
1461 len = buflen;
3dcd25f3 1462 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1463 len = -EFAULT;
1464 out:
1465 free_page((unsigned long)tmp);
1466 return len;
1467}
1468
1469static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1470{
1471 int error = -EACCES;
1472 struct inode *inode = dentry->d_inode;
3dcd25f3 1473 struct path path;
1da177e4 1474
778c1144
EB		 1475 /* Are we allowed to snoop on the tasks file descriptors? */
1476 if (!proc_fd_access_allowed(inode))
1da177e4 1477 goto out;
1da177e4 1478
7773fbc5 1479 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1da177e4
LT		 1480 if (error)
1481 goto out;
1482
3dcd25f3
JB		 1483 error = do_proc_readlink(&path, buffer, buflen);
1484 path_put(&path);
1da177e4 1485out:
1da177e4
LT		 1486 return error;
1487}
1488
c5ef1c42 1489static const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1490 .readlink = proc_pid_readlink,
6d76fa58
LT		 1491 .follow_link = proc_pid_follow_link,
1492 .setattr = proc_setattr,
1da177e4
LT		 1493};
1494
28a6d671
EB		 1495
1496/* building an inode */
1497
1498static int task_dumpable(struct task_struct *task)
1da177e4 1499{
28a6d671
EB		 1500 int dumpable = 0;
1501 struct mm_struct *mm;
1da177e4 1502
28a6d671
EB		 1503 task_lock(task);
1504 mm = task->mm;
1505 if (mm)
6c5d5238 1506 dumpable = get_dumpable(mm);
28a6d671
EB		 1507 task_unlock(task);
1508 if(dumpable == 1)
1509 return 1;
1510 return 0;
1511}
1da177e4 1512
6b4e306a 1513struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1514{
1515 struct inode * inode;
1516 struct proc_inode *ei;
c69e8d9c 1517 const struct cred *cred;
1da177e4 1518
28a6d671 1519 /* We need a new inode */
1da177e4 1520
28a6d671
EB		 1521 inode = new_inode(sb);
1522 if (!inode)
1523 goto out;
1524
1525 /* Common stuff */
1526 ei = PROC_I(inode);
85fe4025 1527 inode->i_ino = get_next_ino();
28a6d671 1528 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
28a6d671
EB		 1529 inode->i_op = &proc_def_inode_operations;
1530
1531 /*
1532 * grab the reference to task.
1533 */
1a657f78 1534 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1535 if (!ei->pid)
1536 goto out_unlock;
1537
28a6d671 1538 if (task_dumpable(task)) {
c69e8d9c
DH		 1539 rcu_read_lock();
1540 cred = __task_cred(task);
1541 inode->i_uid = cred->euid;
1542 inode->i_gid = cred->egid;
1543 rcu_read_unlock();
1da177e4 1544 }
28a6d671
EB		 1545 security_task_to_inode(task, inode);
1546
1da177e4 1547out:
28a6d671
EB		 1548 return inode;
1549
1550out_unlock:
1551 iput(inode);
1552 return NULL;
1da177e4
LT		 1553}
1554
6b4e306a 1555int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1556{
1da177e4 1557 struct inode *inode = dentry->d_inode;
28a6d671 1558 struct task_struct *task;
c69e8d9c 1559 const struct cred *cred;
0499680a 1560 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
c69e8d9c 1561
28a6d671 1562 generic_fillattr(inode, stat);
1da177e4 1563
28a6d671
EB		 1564 rcu_read_lock();
1565 stat->uid = 0;
1566 stat->gid = 0;
1567 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1568 if (task) {
0499680a
VK		 1569 if (!has_pid_permissions(pid, task, 2)) {
1570 rcu_read_unlock();
1571 /*
1572 * This doesn't prevent learning whether PID exists,
1573 * it only makes getattr() consistent with readdir().
1574 */
1575 return -ENOENT;
1576 }
28a6d671
EB		 1577 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1578 task_dumpable(task)) {
c69e8d9c
DH		 1579 cred = __task_cred(task);
1580 stat->uid = cred->euid;
1581 stat->gid = cred->egid;
1da177e4
LT		 1582 }
1583 }
28a6d671 1584 rcu_read_unlock();
d6e71144 1585 return 0;
1da177e4
LT		 1586}
1587
1da177e4
LT		 1588/* dentry stuff */
1589
1590/*
1591 * Exceptional case: normally we are not allowed to unhash a busy
1592 * directory. In this case, however, we can do it - no aliasing problems
1593 * due to the way we treat inodes.
1594 *
1595 * Rewrite the inode's ownerships here because the owning task may have
1596 * performed a setuid(), etc.
99f89551
EB		 1597 *
1598 * Before the /proc/pid/status file was created the only way to read
1599 * the effective uid of a /process was to stat /proc/pid. Reading
1600 * /proc/pid/status is slow enough that procps and other packages
1601 * kept stating /proc/pid. To keep the rules in /proc simple I have
1602 * made this apply to all per process world readable and executable
1603 * directories.
1da177e4 1604 */
6b4e306a 1605int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1da177e4 1606{
34286d66
NP		 1607 struct inode *inode;
1608 struct task_struct *task;
c69e8d9c
DH		 1609 const struct cred *cred;
1610
34286d66
NP		 1611 if (nd && nd->flags & LOOKUP_RCU)
1612 return -ECHILD;
1613
1614 inode = dentry->d_inode;
1615 task = get_proc_task(inode);
1616
99f89551
EB		 1617 if (task) {
1618 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1619 task_dumpable(task)) {
c69e8d9c
DH		 1620 rcu_read_lock();
1621 cred = __task_cred(task);
1622 inode->i_uid = cred->euid;
1623 inode->i_gid = cred->egid;
1624 rcu_read_unlock();
1da177e4
LT		 1625 } else {
1626 inode->i_uid = 0;
1627 inode->i_gid = 0;
1628 }
9ee8ab9f 1629 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1630 security_task_to_inode(task, inode);
99f89551 1631 put_task_struct(task);
1da177e4
LT		 1632 return 1;
1633 }
1634 d_drop(dentry);
1635 return 0;
1636}
1637
fe15ce44 1638static int pid_delete_dentry(const struct dentry * dentry)
99f89551 1639{
28a6d671
EB		 1640 /* Is the task we represent dead?
1641 * If so, then don't put the dentry on the lru list,
1642 * kill it immediately.
1643 */
1644 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1645}
1646
6b4e306a 1647const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1648{
1649 .d_revalidate = pid_revalidate,
1650 .d_delete = pid_delete_dentry,
1651};
1652
1653/* Lookups */
1654
1c0d04c9
EB		 1655/*
1656 * Fill a directory entry.
1657 *
1658 * If possible create the dcache entry and derive our inode number and
1659 * file type from dcache entry.
1660 *
1661 * Since all of the proc inode numbers are dynamically generated, the inode
1662 * numbers do not exist until the inode is cache. This means creating the
1663 * the dcache entry in readdir is necessary to keep the inode numbers
1664 * reported by readdir in sync with the inode numbers reported
1665 * by stat.
1666 */
6b4e306a
EB		 1667int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1668 const char *name, int len,
c5141e6d 1669 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1670{
2fddfeef 1671 struct dentry *child, *dir = filp->f_path.dentry;
61a28784
EB		 1672 struct inode *inode;
1673 struct qstr qname;
1674 ino_t ino = 0;
1675 unsigned type = DT_UNKNOWN;
1676
1677 qname.name = name;
1678 qname.len = len;
1679 qname.hash = full_name_hash(name, len);
1680
1681 child = d_lookup(dir, &qname);
1682 if (!child) {
1683 struct dentry *new;
1684 new = d_alloc(dir, &qname);
1685 if (new) {
1686 child = instantiate(dir->d_inode, new, task, ptr);
1687 if (child)
1688 dput(new);
1689 else
1690 child = new;
1691 }
1692 }
1693 if (!child || IS_ERR(child) || !child->d_inode)
1694 goto end_instantiate;
1695 inode = child->d_inode;
1696 if (inode) {
1697 ino = inode->i_ino;
1698 type = inode->i_mode >> 12;
1699 }
1700 dput(child);
1701end_instantiate:
1702 if (!ino)
1703 ino = find_inode_number(dir, &qname);
1704 if (!ino)
1705 ino = 1;
1706 return filldir(dirent, name, len, filp->f_pos, ino, type);
1707}
1708
28a6d671
EB		 1709static unsigned name_to_int(struct dentry *dentry)
1710{
1711 const char *name = dentry->d_name.name;
1712 int len = dentry->d_name.len;
1713 unsigned n = 0;
1714
1715 if (len > 1 && *name == '0')
1716 goto out;
1717 while (len-- > 0) {
1718 unsigned c = *name++ - '0';
1719 if (c > 9)
1720 goto out;
1721 if (n >= (~0U-9)/10)
1722 goto out;
1723 n *= 10;
1724 n += c;
1725 }
1726 return n;
1727out:
1728 return ~0U;
1729}
1730
27932742
MS		 1731#define PROC_FDINFO_MAX 64
1732
3dcd25f3 1733static int proc_fd_info(struct inode *inode, struct path *path, char *info)
28a6d671 1734{
5e442a49
LT		 1735 struct task_struct *task = get_proc_task(inode);
1736 struct files_struct *files = NULL;
28a6d671
EB		 1737 struct file *file;
1738 int fd = proc_fd(inode);
aa6afca5 1739
5e442a49
LT		 1740 if (task) {
1741 files = get_files_struct(task);
1742 put_task_struct(task);
1743 }
1744 if (files) {
1745 /*
1746 * We are not taking a ref to the file structure, so we must
1747 * hold ->file_lock.
1748 */
1749 spin_lock(&files->file_lock);
1750 file = fcheck_files(files, fd);
1751 if (file) {
1752 unsigned int f_flags;
1753 struct fdtable *fdt;
1754
1755 fdt = files_fdtable(files);
1756 f_flags = file->f_flags & ~O_CLOEXEC;
1dce27c5 1757 if (close_on_exec(fd, fdt))
5e442a49
LT		 1758 f_flags |= O_CLOEXEC;
1759
1760 if (path) {
1761 *path = file->f_path;
1762 path_get(&file->f_path);
1763 }
1764 if (info)
1765 snprintf(info, PROC_FDINFO_MAX,
1766 "pos:\t%lli\n"
1767 "flags:\t0%o\n",
1768 (long long) file->f_pos,
1769 f_flags);
1770 spin_unlock(&files->file_lock);
1771 put_files_struct(files);
1772 return 0;
99f89551 1773 }
5e442a49
LT		 1774 spin_unlock(&files->file_lock);
1775 put_files_struct(files);
1776 }
1777 return -ENOENT;
99f89551
EB		 1778}
1779
7773fbc5 1780static int proc_fd_link(struct dentry *dentry, struct path *path)
27932742 1781{
7773fbc5 1782 return proc_fd_info(dentry->d_inode, path, NULL);
27932742
MS		 1783}
1784
1da177e4
LT		 1785static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1786{
34286d66
NP		 1787 struct inode *inode;
1788 struct task_struct *task;
1789 int fd;
1da177e4 1790 struct files_struct *files;
c69e8d9c 1791 const struct cred *cred;
1da177e4 1792
34286d66
NP		 1793 if (nd && nd->flags & LOOKUP_RCU)
1794 return -ECHILD;
1795
1796 inode = dentry->d_inode;
1797 task = get_proc_task(inode);
1798 fd = proc_fd(inode);
1799
99f89551
EB		 1800 if (task) {
1801 files = get_files_struct(task);
1802 if (files) {
1803 rcu_read_lock();
1804 if (fcheck_files(files, fd)) {
1805 rcu_read_unlock();
1806 put_files_struct(files);
1807 if (task_dumpable(task)) {
c69e8d9c
DH		 1808 rcu_read_lock();
1809 cred = __task_cred(task);
1810 inode->i_uid = cred->euid;
1811 inode->i_gid = cred->egid;
1812 rcu_read_unlock();
99f89551
EB		 1813 } else {
1814 inode->i_uid = 0;
1815 inode->i_gid = 0;
1816 }
9ee8ab9f 1817 inode->i_mode &= ~(S_ISUID | S_ISGID);
99f89551
EB		 1818 security_task_to_inode(task, inode);
1819 put_task_struct(task);
1820 return 1;
1821 }
b835996f 1822 rcu_read_unlock();
1da177e4 1823 put_files_struct(files);
1da177e4 1824 }
99f89551 1825 put_task_struct(task);
1da177e4
LT		 1826 }
1827 d_drop(dentry);
1828 return 0;
1829}
1830
d72f71eb 1831static const struct dentry_operations tid_fd_dentry_operations =
1da177e4
LT		 1832{
1833 .d_revalidate = tid_fd_revalidate,
1834 .d_delete = pid_delete_dentry,
1835};
1836
444ceed8 1837static struct dentry *proc_fd_instantiate(struct inode *dir,
c5141e6d 1838 struct dentry *dentry, struct task_struct *task, const void *ptr)
1da177e4 1839{
c5141e6d 1840 unsigned fd = *(const unsigned *)ptr;
444ceed8
EB		 1841 struct file *file;
1842 struct files_struct *files;
1843 struct inode *inode;
1844 struct proc_inode *ei;
1845 struct dentry *error = ERR_PTR(-ENOENT);
1da177e4 1846
61a28784 1847 inode = proc_pid_make_inode(dir->i_sb, task);
1da177e4
LT		 1848 if (!inode)
1849 goto out;
1850 ei = PROC_I(inode);
aed7a6c4 1851 ei->fd = fd;
1da177e4
LT		 1852 files = get_files_struct(task);
1853 if (!files)
444ceed8 1854 goto out_iput;
1da177e4 1855 inode->i_mode = S_IFLNK;
ca99c1da
DS		 1856
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);
1da177e4
LT		 1862 file = fcheck_files(files, fd);
1863 if (!file)
444ceed8 1864 goto out_unlock;
aeb5d727 1865 if (file->f_mode & FMODE_READ)
1da177e4 1866 inode->i_mode |= S_IRUSR | S_IXUSR;
aeb5d727 1867 if (file->f_mode & FMODE_WRITE)
1da177e4 1868 inode->i_mode |= S_IWUSR | S_IXUSR;
ca99c1da 1869 spin_unlock(&files->file_lock);
1da177e4 1870 put_files_struct(files);
444ceed8 1871
5e442a49 1872 inode->i_op = &proc_pid_link_inode_operations;
1da177e4
LT		 1873 inode->i_size = 64;
1874 ei->op.proc_get_link = proc_fd_link;
fb045adb 1875 d_set_d_op(dentry, &tid_fd_dentry_operations);
1da177e4 1876 d_add(dentry, inode);
cd6a3ce9
EB		 1877 /* Close the race of the process dying before we return the dentry */
1878 if (tid_fd_revalidate(dentry, NULL))
444ceed8 1879 error = NULL;
1da177e4 1880
444ceed8
EB		 1881 out:
1882 return error;
1883out_unlock:
ca99c1da 1884 spin_unlock(&files->file_lock);
1da177e4 1885 put_files_struct(files);
444ceed8 1886out_iput:
1da177e4 1887 iput(inode);
cd6a3ce9 1888 goto out;
1da177e4
LT		 1889}
1890
27932742
MS		 1891static struct dentry *proc_lookupfd_common(struct inode *dir,
1892 struct dentry *dentry,
1893 instantiate_t instantiate)
444ceed8
EB		 1894{
1895 struct task_struct *task = get_proc_task(dir);
1896 unsigned fd = name_to_int(dentry);
1897 struct dentry *result = ERR_PTR(-ENOENT);
1898
1899 if (!task)
1900 goto out_no_task;
1901 if (fd == ~0U)
1902 goto out;
1903
27932742 1904 result = instantiate(dir, dentry, task, &fd);
444ceed8
EB		 1905out:
1906 put_task_struct(task);
1907out_no_task:
1908 return result;
1909}
1910
27932742
MS		 1911static int proc_readfd_common(struct file * filp, void * dirent,
1912 filldir_t filldir, instantiate_t instantiate)
28a6d671 1913{
2fddfeef 1914 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 1915 struct inode *inode = dentry->d_inode;
1916 struct task_struct *p = get_proc_task(inode);
457c2510 1917 unsigned int fd, ino;
28a6d671 1918 int retval;
28a6d671 1919 struct files_struct * files;
1da177e4 1920
28a6d671
EB		 1921 retval = -ENOENT;
1922 if (!p)
1923 goto out_no_task;
1924 retval = 0;
28a6d671
EB		 1925
1926 fd = filp->f_pos;
1927 switch (fd) {
1928 case 0:
1929 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
5e442a49 1930 goto out;
28a6d671
EB		 1931 filp->f_pos++;
1932 case 1:
1933 ino = parent_ino(dentry);
1934 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
5e442a49 1935 goto out;
28a6d671
EB		 1936 filp->f_pos++;
1937 default:
1938 files = get_files_struct(p);
1939 if (!files)
5e442a49 1940 goto out;
28a6d671 1941 rcu_read_lock();
28a6d671 1942 for (fd = filp->f_pos-2;
9b4f526c 1943 fd < files_fdtable(files)->max_fds;
28a6d671 1944 fd++, filp->f_pos++) {
27932742
MS		 1945 char name[PROC_NUMBUF];
1946 int len;
28a6d671
EB		 1947
1948 if (!fcheck_files(files, fd))
1949 continue;
1950 rcu_read_unlock();
1951
27932742
MS		 1952 len = snprintf(name, sizeof(name), "%d", fd);
1953 if (proc_fill_cache(filp, dirent, filldir,
1954 name, len, instantiate,
1955 p, &fd) < 0) {
28a6d671
EB		 1956 rcu_read_lock();
1957 break;
1958 }
1959 rcu_read_lock();
1960 }
1961 rcu_read_unlock();
1962 put_files_struct(files);
1963 }
1964out:
1965 put_task_struct(p);
1966out_no_task:
1967 return retval;
1968}
1969
27932742
MS		 1970static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
1971 struct nameidata *nd)
1972{
1973 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
1974}
1975
1976static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
1977{
1978 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
1979}
1980
1981static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
1982 size_t len, loff_t *ppos)
1983{
1984 char tmp[PROC_FDINFO_MAX];
3dcd25f3 1985 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
27932742
MS		 1986 if (!err)
1987 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
1988 return err;
1989}
1990
1991static const struct file_operations proc_fdinfo_file_operations = {
87df8424 1992 .open = nonseekable_open,
27932742 1993 .read = proc_fdinfo_read,
6038f373 1994 .llseek = no_llseek,
27932742
MS		 1995};
1996
00977a59 1997static const struct file_operations proc_fd_operations = {
28a6d671
EB		 1998 .read = generic_read_dir,
1999 .readdir = proc_readfd,
6038f373 2000 .llseek = default_llseek,
1da177e4
LT		 2001};
2002
640708a2
PE		 2003#ifdef CONFIG_CHECKPOINT_RESTORE
2004
2005/*
2006 * dname_to_vma_addr - maps a dentry name into two unsigned longs
2007 * which represent vma start and end addresses.
2008 */
2009static int dname_to_vma_addr(struct dentry *dentry,
2010 unsigned long *start, unsigned long *end)
2011{
2012 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
2013 return -EINVAL;
2014
2015 return 0;
2016}
2017
2018static int map_files_d_revalidate(struct dentry *dentry, struct nameidata *nd)
2019{
2020 unsigned long vm_start, vm_end;
2021 bool exact_vma_exists = false;
2022 struct mm_struct *mm = NULL;
2023 struct task_struct *task;
2024 const struct cred *cred;
2025 struct inode *inode;
2026 int status = 0;
2027
2028 if (nd && nd->flags & LOOKUP_RCU)
2029 return -ECHILD;
2030
2031 if (!capable(CAP_SYS_ADMIN)) {
2032 status = -EACCES;
2033 goto out_notask;
2034 }
2035
2036 inode = dentry->d_inode;
2037 task = get_proc_task(inode);
2038 if (!task)
2039 goto out_notask;
2040
2041 if (!ptrace_may_access(task, PTRACE_MODE_READ))
2042 goto out;
2043
2044 mm = get_task_mm(task);
2045 if (!mm)
2046 goto out;
2047
2048 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2049 down_read(&mm->mmap_sem);
2050 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
2051 up_read(&mm->mmap_sem);
2052 }
2053
2054 mmput(mm);
2055
2056 if (exact_vma_exists) {
2057 if (task_dumpable(task)) {
2058 rcu_read_lock();
2059 cred = __task_cred(task);
2060 inode->i_uid = cred->euid;
2061 inode->i_gid = cred->egid;
2062 rcu_read_unlock();
2063 } else {
2064 inode->i_uid = 0;
2065 inode->i_gid = 0;
2066 }
2067 security_task_to_inode(task, inode);
2068 status = 1;
2069 }
2070
2071out:
2072 put_task_struct(task);
2073
2074out_notask:
2075 if (status <= 0)
2076 d_drop(dentry);
2077
2078 return status;
2079}
2080
2081static const struct dentry_operations tid_map_files_dentry_operations = {
2082 .d_revalidate = map_files_d_revalidate,
2083 .d_delete = pid_delete_dentry,
2084};
2085
2086static int proc_map_files_get_link(struct dentry *dentry, struct path *path)
2087{
2088 unsigned long vm_start, vm_end;
2089 struct vm_area_struct *vma;
2090 struct task_struct *task;
2091 struct mm_struct *mm;
2092 int rc;
2093
2094 rc = -ENOENT;
2095 task = get_proc_task(dentry->d_inode);
2096 if (!task)
2097 goto out;
2098
2099 mm = get_task_mm(task);
2100 put_task_struct(task);
2101 if (!mm)
2102 goto out;
2103
2104 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2105 if (rc)
2106 goto out_mmput;
2107
2108 down_read(&mm->mmap_sem);
2109 vma = find_exact_vma(mm, vm_start, vm_end);
2110 if (vma && vma->vm_file) {
2111 *path = vma->vm_file->f_path;
2112 path_get(path);
2113 rc = 0;
2114 }
2115 up_read(&mm->mmap_sem);
2116
2117out_mmput:
2118 mmput(mm);
2119out:
2120 return rc;
2121}
2122
2123struct map_files_info {
2124 struct file *file;
2125 unsigned long len;
2126 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
2127};
2128
2129static struct dentry *
2130proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2131 struct task_struct *task, const void *ptr)
2132{
2133 const struct file *file = ptr;
2134 struct proc_inode *ei;
2135 struct inode *inode;
2136
2137 if (!file)
2138 return ERR_PTR(-ENOENT);
2139
2140 inode = proc_pid_make_inode(dir->i_sb, task);
2141 if (!inode)
2142 return ERR_PTR(-ENOENT);
2143
2144 ei = PROC_I(inode);
2145 ei->op.proc_get_link = proc_map_files_get_link;
2146
2147 inode->i_op = &proc_pid_link_inode_operations;
2148 inode->i_size = 64;
2149 inode->i_mode = S_IFLNK;
2150
2151 if (file->f_mode & FMODE_READ)
2152 inode->i_mode |= S_IRUSR;
2153 if (file->f_mode & FMODE_WRITE)
2154 inode->i_mode |= S_IWUSR;
2155
2156 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2157 d_add(dentry, inode);
2158
2159 return NULL;
2160}
2161
2162static struct dentry *proc_map_files_lookup(struct inode *dir,
2163 struct dentry *dentry, struct nameidata *nd)
2164{
2165 unsigned long vm_start, vm_end;
2166 struct vm_area_struct *vma;
2167 struct task_struct *task;
2168 struct dentry *result;
2169 struct mm_struct *mm;
2170
2171 result = ERR_PTR(-EACCES);
2172 if (!capable(CAP_SYS_ADMIN))
2173 goto out;
2174
2175 result = ERR_PTR(-ENOENT);
2176 task = get_proc_task(dir);
2177 if (!task)
2178 goto out;
2179
2180 result = ERR_PTR(-EACCES);
2181 if (lock_trace(task))
2182 goto out_put_task;
2183
2184 result = ERR_PTR(-ENOENT);
2185 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2186 goto out_unlock;
2187
2188 mm = get_task_mm(task);
2189 if (!mm)
2190 goto out_unlock;
2191
2192 down_read(&mm->mmap_sem);
2193 vma = find_exact_vma(mm, vm_start, vm_end);
2194 if (!vma)
2195 goto out_no_vma;
2196
2197 result = proc_map_files_instantiate(dir, dentry, task, vma->vm_file);
2198
2199out_no_vma:
2200 up_read(&mm->mmap_sem);
2201 mmput(mm);
2202out_unlock:
2203 unlock_trace(task);
2204out_put_task:
2205 put_task_struct(task);
2206out:
2207 return result;
2208}
2209
2210static const struct inode_operations proc_map_files_inode_operations = {
2211 .lookup = proc_map_files_lookup,
2212 .permission = proc_fd_permission,
2213 .setattr = proc_setattr,
2214};
2215
2216static int
2217proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
2218{
2219 struct dentry *dentry = filp->f_path.dentry;
2220 struct inode *inode = dentry->d_inode;
2221 struct vm_area_struct *vma;
2222 struct task_struct *task;
2223 struct mm_struct *mm;
2224 ino_t ino;
2225 int ret;
2226
2227 ret = -EACCES;
2228 if (!capable(CAP_SYS_ADMIN))
2229 goto out;
2230
2231 ret = -ENOENT;
2232 task = get_proc_task(inode);
2233 if (!task)
2234 goto out;
2235
2236 ret = -EACCES;
2237 if (lock_trace(task))
2238 goto out_put_task;
2239
2240 ret = 0;
2241 switch (filp->f_pos) {
2242 case 0:
2243 ino = inode->i_ino;
2244 if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0)
2245 goto out_unlock;
2246 filp->f_pos++;
2247 case 1:
2248 ino = parent_ino(dentry);
2249 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2250 goto out_unlock;
2251 filp->f_pos++;
2252 default:
2253 {
2254 unsigned long nr_files, pos, i;
2255 struct flex_array *fa = NULL;
2256 struct map_files_info info;
2257 struct map_files_info *p;
2258
2259 mm = get_task_mm(task);
2260 if (!mm)
2261 goto out_unlock;
2262 down_read(&mm->mmap_sem);
2263
2264 nr_files = 0;
2265
2266 /*
2267 * We need two passes here:
2268 *
2269 * 1) Collect vmas of mapped files with mmap_sem taken
2270 * 2) Release mmap_sem and instantiate entries
2271 *
2272 * otherwise we get lockdep complained, since filldir()
2273 * routine might require mmap_sem taken in might_fault().
2274 */
2275
2276 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2277 if (vma->vm_file && ++pos > filp->f_pos)
2278 nr_files++;
2279 }
2280
2281 if (nr_files) {
2282 fa = flex_array_alloc(sizeof(info), nr_files,
2283 GFP_KERNEL);
2284 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2285 GFP_KERNEL)) {
2286 ret = -ENOMEM;
2287 if (fa)
2288 flex_array_free(fa);
2289 up_read(&mm->mmap_sem);
2290 mmput(mm);
2291 goto out_unlock;
2292 }
2293 for (i = 0, vma = mm->mmap, pos = 2; vma;
2294 vma = vma->vm_next) {
2295 if (!vma->vm_file)
2296 continue;
2297 if (++pos <= filp->f_pos)
2298 continue;
2299
2300 get_file(vma->vm_file);
2301 info.file = vma->vm_file;
2302 info.len = snprintf(info.name,
2303 sizeof(info.name), "%lx-%lx",
2304 vma->vm_start, vma->vm_end);
2305 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2306 BUG();
2307 }
2308 }
2309 up_read(&mm->mmap_sem);
2310
2311 for (i = 0; i < nr_files; i++) {
2312 p = flex_array_get(fa, i);
2313 ret = proc_fill_cache(filp, dirent, filldir,
2314 p->name, p->len,
2315 proc_map_files_instantiate,
2316 task, p->file);
2317 if (ret)
2318 break;
2319 filp->f_pos++;
2320 fput(p->file);
2321 }
2322 for (; i < nr_files; i++) {
2323 /*
2324 * In case of error don't forget
2325 * to put rest of file refs.
2326 */
2327 p = flex_array_get(fa, i);
2328 fput(p->file);
2329 }
2330 if (fa)
2331 flex_array_free(fa);
2332 mmput(mm);
2333 }
2334 }
2335
2336out_unlock:
2337 unlock_trace(task);
2338out_put_task:
2339 put_task_struct(task);
2340out:
2341 return ret;
2342}
2343
2344static const struct file_operations proc_map_files_operations = {
2345 .read = generic_read_dir,
2346 .readdir = proc_map_files_readdir,
2347 .llseek = default_llseek,
2348};
2349
2350#endif /* CONFIG_CHECKPOINT_RESTORE */
2351
8948e11f
AD		 2352/*
2353 * /proc/pid/fd needs a special permission handler so that a process can still
2354 * access /proc/self/fd after it has executed a setuid().
2355 */
10556cb2 2356static int proc_fd_permission(struct inode *inode, int mask)
8948e11f 2357{
2830ba7f 2358 int rv = generic_permission(inode, mask);
8948e11f
AD		 2359 if (rv == 0)
2360 return 0;
2361 if (task_pid(current) == proc_pid(inode))
2362 rv = 0;
2363 return rv;
2364}
2365
1da177e4
LT		 2366/*
2367 * proc directories can do almost nothing..
2368 */
c5ef1c42 2369static const struct inode_operations proc_fd_inode_operations = {
1da177e4 2370 .lookup = proc_lookupfd,
8948e11f 2371 .permission = proc_fd_permission,
6d76fa58 2372 .setattr = proc_setattr,
1da177e4
LT		 2373};
2374
27932742
MS		 2375static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2376 struct dentry *dentry, struct task_struct *task, const void *ptr)
2377{
2378 unsigned fd = *(unsigned *)ptr;
2379 struct inode *inode;
2380 struct proc_inode *ei;
2381 struct dentry *error = ERR_PTR(-ENOENT);
2382
2383 inode = proc_pid_make_inode(dir->i_sb, task);
2384 if (!inode)
2385 goto out;
2386 ei = PROC_I(inode);
2387 ei->fd = fd;
2388 inode->i_mode = S_IFREG | S_IRUSR;
2389 inode->i_fop = &proc_fdinfo_file_operations;
fb045adb 2390 d_set_d_op(dentry, &tid_fd_dentry_operations);
27932742
MS		 2391 d_add(dentry, inode);
2392 /* Close the race of the process dying before we return the dentry */
2393 if (tid_fd_revalidate(dentry, NULL))
2394 error = NULL;
2395
2396 out:
2397 return error;
2398}
2399
2400static struct dentry *proc_lookupfdinfo(struct inode *dir,
2401 struct dentry *dentry,
2402 struct nameidata *nd)
2403{
2404 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2405}
2406
2407static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2408{
2409 return proc_readfd_common(filp, dirent, filldir,
2410 proc_fdinfo_instantiate);
2411}
2412
2413static const struct file_operations proc_fdinfo_operations = {
2414 .read = generic_read_dir,
2415 .readdir = proc_readfdinfo,
6038f373 2416 .llseek = default_llseek,
27932742
MS		 2417};
2418
2419/*
2420 * proc directories can do almost nothing..
2421 */
2422static const struct inode_operations proc_fdinfo_inode_operations = {
2423 .lookup = proc_lookupfdinfo,
2424 .setattr = proc_setattr,
2425};
2426
2427
444ceed8 2428static struct dentry *proc_pident_instantiate(struct inode *dir,
c5141e6d 2429 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2430{
c5141e6d 2431 const struct pid_entry *p = ptr;
444ceed8
EB		 2432 struct inode *inode;
2433 struct proc_inode *ei;
bd6daba9 2434 struct dentry *error = ERR_PTR(-ENOENT);
444ceed8 2435
61a28784 2436 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2437 if (!inode)
2438 goto out;
2439
2440 ei = PROC_I(inode);
2441 inode->i_mode = p->mode;
2442 if (S_ISDIR(inode->i_mode))
bfe86848 2443 set_nlink(inode, 2); /* Use getattr to fix if necessary */
444ceed8
EB		 2444 if (p->iop)
2445 inode->i_op = p->iop;
2446 if (p->fop)
2447 inode->i_fop = p->fop;
2448 ei->op = p->op;
fb045adb 2449 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2450 d_add(dentry, inode);
2451 /* Close the race of the process dying before we return the dentry */
2452 if (pid_revalidate(dentry, NULL))
2453 error = NULL;
2454out:
2455 return error;
2456}
2457
1da177e4
LT		 2458static struct dentry *proc_pident_lookup(struct inode *dir,
2459 struct dentry *dentry,
c5141e6d 2460 const struct pid_entry *ents,
7bcd6b0e 2461 unsigned int nents)
1da177e4 2462{
cd6a3ce9 2463 struct dentry *error;
99f89551 2464 struct task_struct *task = get_proc_task(dir);
c5141e6d 2465 const struct pid_entry *p, *last;
1da177e4 2466
cd6a3ce9 2467 error = ERR_PTR(-ENOENT);
1da177e4 2468
99f89551
EB		 2469 if (!task)
2470 goto out_no_task;
1da177e4 2471
20cdc894
EB		 2472 /*
2473 * Yes, it does not scale. And it should not. Don't add
2474 * new entries into /proc/<tgid>/ without very good reasons.
2475 */
7bcd6b0e
EB		 2476 last = &ents[nents - 1];
2477 for (p = ents; p <= last; p++) {
1da177e4
LT		 2478 if (p->len != dentry->d_name.len)
2479 continue;
2480 if (!memcmp(dentry->d_name.name, p->name, p->len))
2481 break;
2482 }
7bcd6b0e 2483 if (p > last)
1da177e4
LT		 2484 goto out;
2485
444ceed8 2486 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2487out:
99f89551
EB		 2488 put_task_struct(task);
2489out_no_task:
cd6a3ce9 2490 return error;
1da177e4
LT		 2491}
2492
c5141e6d
ED		 2493static int proc_pident_fill_cache(struct file *filp, void *dirent,
2494 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2495{
2496 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2497 proc_pident_instantiate, task, p);
2498}
2499
28a6d671
EB		 2500static int proc_pident_readdir(struct file *filp,
2501 void *dirent, filldir_t filldir,
c5141e6d 2502 const struct pid_entry *ents, unsigned int nents)
28a6d671
EB		 2503{
2504 int i;
2fddfeef 2505 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2506 struct inode *inode = dentry->d_inode;
2507 struct task_struct *task = get_proc_task(inode);
c5141e6d 2508 const struct pid_entry *p, *last;
28a6d671
EB		 2509 ino_t ino;
2510 int ret;
2511
2512 ret = -ENOENT;
2513 if (!task)
61a28784 2514 goto out_no_task;
28a6d671
EB		 2515
2516 ret = 0;
28a6d671
EB		 2517 i = filp->f_pos;
2518 switch (i) {
2519 case 0:
2520 ino = inode->i_ino;
2521 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2522 goto out;
2523 i++;
2524 filp->f_pos++;
2525 /* fall through */
2526 case 1:
2527 ino = parent_ino(dentry);
2528 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2529 goto out;
2530 i++;
2531 filp->f_pos++;
2532 /* fall through */
2533 default:
2534 i -= 2;
2535 if (i >= nents) {
2536 ret = 1;
2537 goto out;
2538 }
2539 p = ents + i;
7bcd6b0e
EB		 2540 last = &ents[nents - 1];
2541 while (p <= last) {
61a28784 2542 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
28a6d671
EB		 2543 goto out;
2544 filp->f_pos++;
2545 p++;
2546 }
2547 }
2548
2549 ret = 1;
2550out:
61a28784
EB		 2551 put_task_struct(task);
2552out_no_task:
28a6d671 2553 return ret;
1da177e4
LT		 2554}
2555
28a6d671
EB		 2556#ifdef CONFIG_SECURITY
2557static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2558 size_t count, loff_t *ppos)
2559{
2fddfeef 2560 struct inode * inode = file->f_path.dentry->d_inode;
04ff9708 2561 char *p = NULL;
28a6d671
EB		 2562 ssize_t length;
2563 struct task_struct *task = get_proc_task(inode);
2564
28a6d671 2565 if (!task)
04ff9708 2566 return -ESRCH;
28a6d671
EB		 2567
2568 length = security_getprocattr(task,
2fddfeef 2569 (char*)file->f_path.dentry->d_name.name,
04ff9708 2570 &p);
28a6d671 2571 put_task_struct(task);
04ff9708
AV		 2572 if (length > 0)
2573 length = simple_read_from_buffer(buf, count, ppos, p, length);
2574 kfree(p);
28a6d671 2575 return length;
1da177e4
LT		 2576}
2577
28a6d671
EB		 2578static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2579 size_t count, loff_t *ppos)
2580{
2fddfeef 2581 struct inode * inode = file->f_path.dentry->d_inode;
28a6d671
EB		 2582 char *page;
2583 ssize_t length;
2584 struct task_struct *task = get_proc_task(inode);
2585
2586 length = -ESRCH;
2587 if (!task)
2588 goto out_no_task;
2589 if (count > PAGE_SIZE)
2590 count = PAGE_SIZE;
2591
2592 /* No partial writes. */
2593 length = -EINVAL;
2594 if (*ppos != 0)
2595 goto out;
2596
2597 length = -ENOMEM;
e12ba74d 2598 page = (char*)__get_free_page(GFP_TEMPORARY);
28a6d671
EB		 2599 if (!page)
2600 goto out;
2601
2602 length = -EFAULT;
2603 if (copy_from_user(page, buf, count))
2604 goto out_free;
2605
107db7c7 2606 /* Guard against adverse ptrace interaction */
9b1bf12d 2607 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2608 if (length < 0)
2609 goto out_free;
2610
28a6d671 2611 length = security_setprocattr(task,
2fddfeef 2612 (char*)file->f_path.dentry->d_name.name,
28a6d671 2613 (void*)page, count);
9b1bf12d 2614 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671
EB		 2615out_free:
2616 free_page((unsigned long) page);
2617out:
2618 put_task_struct(task);
2619out_no_task:
2620 return length;
2621}
2622
00977a59 2623static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2624 .read = proc_pid_attr_read,
2625 .write = proc_pid_attr_write,
87df8424 2626 .llseek = generic_file_llseek,
28a6d671
EB		 2627};
2628
c5141e6d 2629static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2630 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2631 REG("prev", S_IRUGO, proc_pid_attr_operations),
2632 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2633 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2634 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2635 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2636};
2637
72d9dcfc 2638static int proc_attr_dir_readdir(struct file * filp,
28a6d671
EB		 2639 void * dirent, filldir_t filldir)
2640{
2641 return proc_pident_readdir(filp,dirent,filldir,
72d9dcfc 2642 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2643}
2644
00977a59 2645static const struct file_operations proc_attr_dir_operations = {
1da177e4 2646 .read = generic_read_dir,
72d9dcfc 2647 .readdir = proc_attr_dir_readdir,
6038f373 2648 .llseek = default_llseek,
1da177e4
LT		 2649};
2650
72d9dcfc 2651static struct dentry *proc_attr_dir_lookup(struct inode *dir,
28a6d671
EB		 2652 struct dentry *dentry, struct nameidata *nd)
2653{
7bcd6b0e
EB		 2654 return proc_pident_lookup(dir, dentry,
2655 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2656}
2657
c5ef1c42 2658static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2659 .lookup = proc_attr_dir_lookup,
99f89551 2660 .getattr = pid_getattr,
6d76fa58 2661 .setattr = proc_setattr,
1da177e4
LT		 2662};
2663
28a6d671
EB		 2664#endif
2665
698ba7b5 2666#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2667static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2668 size_t count, loff_t *ppos)
2669{
2670 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2671 struct mm_struct *mm;
2672 char buffer[PROC_NUMBUF];
2673 size_t len;
2674 int ret;
2675
2676 if (!task)
2677 return -ESRCH;
2678
2679 ret = 0;
2680 mm = get_task_mm(task);
2681 if (mm) {
2682 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2683 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2684 MMF_DUMP_FILTER_SHIFT));
2685 mmput(mm);
2686 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2687 }
2688
2689 put_task_struct(task);
2690
2691 return ret;
2692}
2693
2694static ssize_t proc_coredump_filter_write(struct file *file,
2695 const char __user *buf,
2696 size_t count,
2697 loff_t *ppos)
2698{
2699 struct task_struct *task;
2700 struct mm_struct *mm;
2701 char buffer[PROC_NUMBUF], *end;
2702 unsigned int val;
2703 int ret;
2704 int i;
2705 unsigned long mask;
2706
2707 ret = -EFAULT;
2708 memset(buffer, 0, sizeof(buffer));
2709 if (count > sizeof(buffer) - 1)
2710 count = sizeof(buffer) - 1;
2711 if (copy_from_user(buffer, buf, count))
2712 goto out_no_task;
2713
2714 ret = -EINVAL;
2715 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2716 if (*end == '\n')
2717 end++;
2718 if (end - buffer == 0)
2719 goto out_no_task;
2720
2721 ret = -ESRCH;
2722 task = get_proc_task(file->f_dentry->d_inode);
2723 if (!task)
2724 goto out_no_task;
2725
2726 ret = end - buffer;
2727 mm = get_task_mm(task);
2728 if (!mm)
2729 goto out_no_mm;
2730
2731 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2732 if (val & mask)
2733 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2734 else
2735 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2736 }
2737
2738 mmput(mm);
2739 out_no_mm:
2740 put_task_struct(task);
2741 out_no_task:
2742 return ret;
2743}
2744
2745static const struct file_operations proc_coredump_filter_operations = {
2746 .read = proc_coredump_filter_read,
2747 .write = proc_coredump_filter_write,
87df8424 2748 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2749};
2750#endif
2751
28a6d671
EB		 2752/*
2753 * /proc/self:
2754 */
2755static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2756 int buflen)
2757{
488e5bc4 2758 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2759 pid_t tgid = task_tgid_nr_ns(current, ns);
28a6d671 2760 char tmp[PROC_NUMBUF];
b55fcb22 2761 if (!tgid)
488e5bc4 2762 return -ENOENT;
b55fcb22 2763 sprintf(tmp, "%d", tgid);
28a6d671
EB		 2764 return vfs_readlink(dentry,buffer,buflen,tmp);
2765}
2766
2767static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2768{
488e5bc4 2769 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2770 pid_t tgid = task_tgid_nr_ns(current, ns);
7fee4868
AV		 2771 char *name = ERR_PTR(-ENOENT);
2772 if (tgid) {
2773 name = __getname();
2774 if (!name)
2775 name = ERR_PTR(-ENOMEM);
2776 else
2777 sprintf(name, "%d", tgid);
2778 }
2779 nd_set_link(nd, name);
2780 return NULL;
2781}
2782
2783static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2784 void *cookie)
2785{
2786 char *s = nd_get_link(nd);
2787 if (!IS_ERR(s))
2788 __putname(s);
28a6d671
EB		 2789}
2790
c5ef1c42 2791static const struct inode_operations proc_self_inode_operations = {
28a6d671
EB		 2792 .readlink = proc_self_readlink,
2793 .follow_link = proc_self_follow_link,
7fee4868 2794 .put_link = proc_self_put_link,
28a6d671
EB		 2795};
2796
801199ce
EB		 2797/*
2798 * proc base
2799 *
2800 * These are the directory entries in the root directory of /proc
2801 * that properly belong to the /proc filesystem, as they describe
2802 * describe something that is process related.
2803 */
c5141e6d 2804static const struct pid_entry proc_base_stuff[] = {
61a28784 2805 NOD("self", S_IFLNK|S_IRWXUGO,
801199ce 2806 &proc_self_inode_operations, NULL, {}),
801199ce
EB		 2807};
2808
444ceed8 2809static struct dentry *proc_base_instantiate(struct inode *dir,
c5141e6d 2810 struct dentry *dentry, struct task_struct *task, const void *ptr)
801199ce 2811{
c5141e6d 2812 const struct pid_entry *p = ptr;
801199ce 2813 struct inode *inode;
801199ce 2814 struct proc_inode *ei;
73d36460 2815 struct dentry *error;
801199ce
EB		 2816
2817 /* Allocate the inode */
2818 error = ERR_PTR(-ENOMEM);
2819 inode = new_inode(dir->i_sb);
2820 if (!inode)
2821 goto out;
2822
2823 /* Initialize the inode */
2824 ei = PROC_I(inode);
85fe4025 2825 inode->i_ino = get_next_ino();
801199ce 2826 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
801199ce
EB		 2827
2828 /*
2829 * grab the reference to the task.
2830 */
1a657f78 2831 ei->pid = get_task_pid(task, PIDTYPE_PID);
801199ce
EB		 2832 if (!ei->pid)
2833 goto out_iput;
2834
801199ce
EB		 2835 inode->i_mode = p->mode;
2836 if (S_ISDIR(inode->i_mode))
bfe86848 2837 set_nlink(inode, 2);
801199ce
EB		 2838 if (S_ISLNK(inode->i_mode))
2839 inode->i_size = 64;
2840 if (p->iop)
2841 inode->i_op = p->iop;
2842 if (p->fop)
2843 inode->i_fop = p->fop;
2844 ei->op = p->op;
801199ce
EB		 2845 d_add(dentry, inode);
2846 error = NULL;
2847out:
801199ce
EB		 2848 return error;
2849out_iput:
2850 iput(inode);
2851 goto out;
2852}
2853
444ceed8
EB		 2854static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2855{
2856 struct dentry *error;
2857 struct task_struct *task = get_proc_task(dir);
c5141e6d 2858 const struct pid_entry *p, *last;
444ceed8
EB		 2859
2860 error = ERR_PTR(-ENOENT);
2861
2862 if (!task)
2863 goto out_no_task;
2864
2865 /* Lookup the directory entry */
7bcd6b0e
EB		 2866 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2867 for (p = proc_base_stuff; p <= last; p++) {
444ceed8
EB		 2868 if (p->len != dentry->d_name.len)
2869 continue;
2870 if (!memcmp(dentry->d_name.name, p->name, p->len))
2871 break;
2872 }
7bcd6b0e 2873 if (p > last)
444ceed8
EB		 2874 goto out;
2875
2876 error = proc_base_instantiate(dir, dentry, task, p);
2877
2878out:
2879 put_task_struct(task);
2880out_no_task:
2881 return error;
2882}
2883
c5141e6d
ED		 2884static int proc_base_fill_cache(struct file *filp, void *dirent,
2885 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2886{
2887 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2888 proc_base_instantiate, task, p);
2889}
2890
aba76fdb 2891#ifdef CONFIG_TASK_IO_ACCOUNTING
297c5d92
AR		 2892static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2893{
940389b8 2894 struct task_io_accounting acct = task->ioac;
5995477a 2895 unsigned long flags;
293eb1e7 2896 int result;
5995477a 2897
293eb1e7
VK		 2898 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2899 if (result)
2900 return result;
2901
2902 if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
2903 result = -EACCES;
2904 goto out_unlock;
2905 }
1d1221f3 2906
5995477a
AR		 2907 if (whole && lock_task_sighand(task, &flags)) {
2908 struct task_struct *t = task;
2909
2910 task_io_accounting_add(&acct, &task->signal->ioac);
2911 while_each_thread(task, t)
2912 task_io_accounting_add(&acct, &t->ioac);
2913
2914 unlock_task_sighand(task, &flags);
297c5d92 2915 }
293eb1e7 2916 result = sprintf(buffer,
aba76fdb
AM		 2917 "rchar: %llu\n"
2918 "wchar: %llu\n"
2919 "syscr: %llu\n"
2920 "syscw: %llu\n"
2921 "read_bytes: %llu\n"
2922 "write_bytes: %llu\n"
2923 "cancelled_write_bytes: %llu\n",
7c44319d
AB		 2924 (unsigned long long)acct.rchar,
2925 (unsigned long long)acct.wchar,
2926 (unsigned long long)acct.syscr,
2927 (unsigned long long)acct.syscw,
2928 (unsigned long long)acct.read_bytes,
2929 (unsigned long long)acct.write_bytes,
2930 (unsigned long long)acct.cancelled_write_bytes);
293eb1e7
VK		 2931out_unlock:
2932 mutex_unlock(&task->signal->cred_guard_mutex);
2933 return result;
297c5d92
AR		 2934}
2935
2936static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2937{
2938 return do_io_accounting(task, buffer, 0);
aba76fdb 2939}
297c5d92
AR		 2940
2941static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2942{
2943 return do_io_accounting(task, buffer, 1);
2944}
2945#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2946
22d917d8
EB		 2947#ifdef CONFIG_USER_NS
2948static int proc_id_map_open(struct inode *inode, struct file *file,
2949 struct seq_operations *seq_ops)
2950{
2951 struct user_namespace *ns = NULL;
2952 struct task_struct *task;
2953 struct seq_file *seq;
2954 int ret = -EINVAL;
2955
2956 task = get_proc_task(inode);
2957 if (task) {
2958 rcu_read_lock();
2959 ns = get_user_ns(task_cred_xxx(task, user_ns));
2960 rcu_read_unlock();
2961 put_task_struct(task);
2962 }
2963 if (!ns)
2964 goto err;
2965
2966 ret = seq_open(file, seq_ops);
2967 if (ret)
2968 goto err_put_ns;
2969
2970 seq = file->private_data;
2971 seq->private = ns;
2972
2973 return 0;
2974err_put_ns:
2975 put_user_ns(ns);
2976err:
2977 return ret;
2978}
2979
2980static int proc_id_map_release(struct inode *inode, struct file *file)
2981{
2982 struct seq_file *seq = file->private_data;
2983 struct user_namespace *ns = seq->private;
2984 put_user_ns(ns);
2985 return seq_release(inode, file);
2986}
2987
2988static int proc_uid_map_open(struct inode *inode, struct file *file)
2989{
2990 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2991}
2992
2993static int proc_gid_map_open(struct inode *inode, struct file *file)
2994{
2995 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2996}
2997
2998static const struct file_operations proc_uid_map_operations = {
2999 .open = proc_uid_map_open,
3000 .write = proc_uid_map_write,
3001 .read = seq_read,
3002 .llseek = seq_lseek,
3003 .release = proc_id_map_release,
3004};
3005
3006static const struct file_operations proc_gid_map_operations = {
3007 .open = proc_gid_map_open,
3008 .write = proc_gid_map_write,
3009 .read = seq_read,
3010 .llseek = seq_lseek,
3011 .release = proc_id_map_release,
3012};
3013#endif /* CONFIG_USER_NS */
3014
47830723
KC		 3015static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
3016 struct pid *pid, struct task_struct *task)
3017{
a9712bc1
AV		 3018 int err = lock_trace(task);
3019 if (!err) {
3020 seq_printf(m, "%08x\n", task->personality);
3021 unlock_trace(task);
3022 }
3023 return err;
47830723
KC		 3024}
3025
28a6d671
EB		 3026/*
3027 * Thread groups
3028 */
00977a59 3029static const struct file_operations proc_task_operations;
c5ef1c42 3030static const struct inode_operations proc_task_inode_operations;
20cdc894 3031
c5141e6d 3032static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 3033 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
3034 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
640708a2
PE		 3035#ifdef CONFIG_CHECKPOINT_RESTORE
3036 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
3037#endif
631f9c18 3038 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 3039 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
b2211a36 3040#ifdef CONFIG_NET
631f9c18 3041 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 3042#endif
631f9c18
AD		 3043 REG("environ", S_IRUSR, proc_environ_operations),
3044 INF("auxv", S_IRUSR, proc_pid_auxv),
3045 ONE("status", S_IRUGO, proc_pid_status),
a9712bc1 3046 ONE("personality", S_IRUGO, proc_pid_personality),
3036e7b4 3047 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3048#ifdef CONFIG_SCHED_DEBUG
631f9c18 3049 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
5091faa4
MG		 3050#endif
3051#ifdef CONFIG_SCHED_AUTOGROUP
3052 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
ebcb6734 3053#endif
4614a696 3054 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3055#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
a9712bc1 3056 INF("syscall", S_IRUGO, proc_pid_syscall),
43ae34cb 3057#endif
631f9c18
AD		 3058 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3059 ONE("stat", S_IRUGO, proc_tgid_stat),
3060 ONE("statm", S_IRUGO, proc_pid_statm),
b7643757 3061 REG("maps", S_IRUGO, proc_pid_maps_operations),
28a6d671 3062#ifdef CONFIG_NUMA
b7643757 3063 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
28a6d671 3064#endif
631f9c18
AD		 3065 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3066 LNK("cwd", proc_cwd_link),
3067 LNK("root", proc_root_link),
3068 LNK("exe", proc_exe_link),
3069 REG("mounts", S_IRUGO, proc_mounts_operations),
3070 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3071 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 3072#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18 3073 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
b7643757 3074 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
ca6b0bf0 3075 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 3076#endif
3077#ifdef CONFIG_SECURITY
631f9c18 3078 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3079#endif
3080#ifdef CONFIG_KALLSYMS
631f9c18 3081 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3082#endif
2ec220e2 3083#ifdef CONFIG_STACKTRACE
a9712bc1 3084 ONE("stack", S_IRUGO, proc_pid_stack),
28a6d671
EB		 3085#endif
3086#ifdef CONFIG_SCHEDSTATS
631f9c18 3087 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3088#endif
9745512c 3089#ifdef CONFIG_LATENCYTOP
631f9c18 3090 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3091#endif
8793d854 3092#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3093 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3094#endif
3095#ifdef CONFIG_CGROUPS
631f9c18 3096 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3097#endif
631f9c18
AD		 3098 INF("oom_score", S_IRUGO, proc_oom_score),
3099 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3100 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3101#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 3102 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3103 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3104#endif
f4f154fd 3105#ifdef CONFIG_FAULT_INJECTION
631f9c18 3106 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3107#endif
698ba7b5 3108#ifdef CONFIG_ELF_CORE
631f9c18 3109 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 3110#endif
aba76fdb 3111#ifdef CONFIG_TASK_IO_ACCOUNTING
1d1221f3 3112 INF("io", S_IRUSR, proc_tgid_io_accounting),
aba76fdb 3113#endif
f133ecca
CM		 3114#ifdef CONFIG_HARDWALL
3115 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3116#endif
22d917d8
EB		 3117#ifdef CONFIG_USER_NS
3118 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3119 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3120#endif
28a6d671 3121};
1da177e4 3122
28a6d671 3123static int proc_tgid_base_readdir(struct file * filp,
1da177e4
LT		 3124 void * dirent, filldir_t filldir)
3125{
3126 return proc_pident_readdir(filp,dirent,filldir,
28a6d671 3127 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 3128}
3129
00977a59 3130static const struct file_operations proc_tgid_base_operations = {
1da177e4 3131 .read = generic_read_dir,
28a6d671 3132 .readdir = proc_tgid_base_readdir,
6038f373 3133 .llseek = default_llseek,
1da177e4
LT		 3134};
3135
28a6d671 3136static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3137 return proc_pident_lookup(dir, dentry,
3138 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 3139}
3140
c5ef1c42 3141static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 3142 .lookup = proc_tgid_base_lookup,
99f89551 3143 .getattr = pid_getattr,
6d76fa58 3144 .setattr = proc_setattr,
0499680a 3145 .permission = proc_pid_permission,
1da177e4 3146};
1da177e4 3147
60347f67 3148static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 3149{
48e6484d 3150 struct dentry *dentry, *leader, *dir;
8578cea7 3151 char buf[PROC_NUMBUF];
48e6484d
EB		 3152 struct qstr name;
3153
3154 name.name = buf;
60347f67
PE		 3155 name.len = snprintf(buf, sizeof(buf), "%d", pid);
3156 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 3157 if (dentry) {
29f12ca3 3158 shrink_dcache_parent(dentry);
48e6484d
EB		 3159 d_drop(dentry);
3160 dput(dentry);
3161 }
1da177e4 3162
48e6484d 3163 name.name = buf;
60347f67
PE		 3164 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
3165 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 3166 if (!leader)
3167 goto out;
1da177e4 3168
48e6484d
EB		 3169 name.name = "task";
3170 name.len = strlen(name.name);
3171 dir = d_hash_and_lookup(leader, &name);
3172 if (!dir)
3173 goto out_put_leader;
3174
3175 name.name = buf;
60347f67 3176 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 3177 dentry = d_hash_and_lookup(dir, &name);
3178 if (dentry) {
3179 shrink_dcache_parent(dentry);
3180 d_drop(dentry);
3181 dput(dentry);
1da177e4 3182 }
48e6484d
EB		 3183
3184 dput(dir);
3185out_put_leader:
3186 dput(leader);
3187out:
3188 return;
1da177e4
LT		 3189}
3190
0895e91d
RD		 3191/**
3192 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3193 * @task: task that should be flushed.
3194 *
3195 * When flushing dentries from proc, one needs to flush them from global
60347f67 3196 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 3197 * in. This call is supposed to do all of this job.
3198 *
3199 * Looks in the dcache for
3200 * /proc/@pid
3201 * /proc/@tgid/task/@pid
3202 * if either directory is present flushes it and all of it'ts children
3203 * from the dcache.
3204 *
3205 * It is safe and reasonable to cache /proc entries for a task until
3206 * that task exits. After that they just clog up the dcache with
3207 * useless entries, possibly causing useful dcache entries to be
3208 * flushed instead. This routine is proved to flush those useless
3209 * dcache entries at process exit time.
3210 *
3211 * NOTE: This routine is just an optimization so it does not guarantee
3212 * that no dcache entries will exist at process exit time it
3213 * just makes it very unlikely that any will persist.
60347f67
PE		 3214 */
3215
3216void proc_flush_task(struct task_struct *task)
3217{
9fcc2d15 3218 int i;
9b4d1cbe 3219 struct pid *pid, *tgid;
130f77ec
PE		 3220 struct upid *upid;
3221
130f77ec 3222 pid = task_pid(task);
9b4d1cbe 3223 tgid = task_tgid(task);
130f77ec 3224
9fcc2d15 3225 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 3226 upid = &pid->numbers[i];
3227 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 3228 tgid->numbers[i].nr);
130f77ec 3229 }
6f4e6433
PE		 3230
3231 upid = &pid->numbers[pid->level];
3232 if (upid->nr == 1)
3233 pid_ns_release_proc(upid->ns);
60347f67
PE		 3234}
3235
9711ef99
AB		 3236static struct dentry *proc_pid_instantiate(struct inode *dir,
3237 struct dentry * dentry,
c5141e6d 3238 struct task_struct *task, const void *ptr)
444ceed8
EB		 3239{
3240 struct dentry *error = ERR_PTR(-ENOENT);
3241 struct inode *inode;
3242
61a28784 3243 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3244 if (!inode)
3245 goto out;
3246
3247 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3248 inode->i_op = &proc_tgid_base_inode_operations;
3249 inode->i_fop = &proc_tgid_base_operations;
3250 inode->i_flags|=S_IMMUTABLE;
aed54175 3251
bfe86848
MS		 3252 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff,
3253 ARRAY_SIZE(tgid_base_stuff)));
444ceed8 3254
fb045adb 3255 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3256
3257 d_add(dentry, inode);
3258 /* Close the race of the process dying before we return the dentry */
3259 if (pid_revalidate(dentry, NULL))
3260 error = NULL;
3261out:
3262 return error;
3263}
3264
1da177e4
LT		 3265struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3266{
73d36460 3267 struct dentry *result;
1da177e4 3268 struct task_struct *task;
1da177e4 3269 unsigned tgid;
b488893a 3270 struct pid_namespace *ns;
1da177e4 3271
801199ce
EB		 3272 result = proc_base_lookup(dir, dentry);
3273 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
3274 goto out;
3275
1da177e4
LT		 3276 tgid = name_to_int(dentry);
3277 if (tgid == ~0U)
3278 goto out;
3279
b488893a 3280 ns = dentry->d_sb->s_fs_info;
de758734 3281 rcu_read_lock();
b488893a 3282 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 3283 if (task)
3284 get_task_struct(task);
de758734 3285 rcu_read_unlock();
1da177e4
LT		 3286 if (!task)
3287 goto out;
3288
444ceed8 3289 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 3290 put_task_struct(task);
1da177e4 3291out:
cd6a3ce9 3292 return result;
1da177e4
LT		 3293}
3294
1da177e4 3295/*
0804ef4b 3296 * Find the first task with tgid >= tgid
0bc58a91 3297 *
1da177e4 3298 */
19fd4bb2
EB		 3299struct tgid_iter {
3300 unsigned int tgid;
0804ef4b 3301 struct task_struct *task;
19fd4bb2
EB		 3302};
3303static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3304{
0804ef4b 3305 struct pid *pid;
1da177e4 3306
19fd4bb2
EB		 3307 if (iter.task)
3308 put_task_struct(iter.task);
454cc105 3309 rcu_read_lock();
0804ef4b 3310retry:
19fd4bb2
EB		 3311 iter.task = NULL;
3312 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 3313 if (pid) {
19fd4bb2
EB		 3314 iter.tgid = pid_nr_ns(pid, ns);
3315 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 3316 /* What we to know is if the pid we have find is the
3317 * pid of a thread_group_leader. Testing for task
3318 * being a thread_group_leader is the obvious thing
3319 * todo but there is a window when it fails, due to
3320 * the pid transfer logic in de_thread.
3321 *
3322 * So we perform the straight forward test of seeing
3323 * if the pid we have found is the pid of a thread
3324 * group leader, and don't worry if the task we have
3325 * found doesn't happen to be a thread group leader.
3326 * As we don't care in the case of readdir.
3327 */
19fd4bb2
EB		 3328 if (!iter.task || !has_group_leader_pid(iter.task)) {
3329 iter.tgid += 1;
0804ef4b 3330 goto retry;
19fd4bb2
EB		 3331 }
3332 get_task_struct(iter.task);
0bc58a91 3333 }
454cc105 3334 rcu_read_unlock();
19fd4bb2 3335 return iter;
1da177e4
LT		 3336}
3337
7bcd6b0e 3338#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
0804ef4b 3339
61a28784 3340static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
19fd4bb2 3341 struct tgid_iter iter)
61a28784
EB		 3342{
3343 char name[PROC_NUMBUF];
19fd4bb2 3344 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
61a28784 3345 return proc_fill_cache(filp, dirent, filldir, name, len,
19fd4bb2 3346 proc_pid_instantiate, iter.task, NULL);
61a28784
EB		 3347}
3348
0499680a
VK		 3349static int fake_filldir(void *buf, const char *name, int namelen,
3350 loff_t offset, u64 ino, unsigned d_type)
3351{
3352 return 0;
3353}
3354
1da177e4
LT		 3355/* for the /proc/ directory itself, after non-process stuff has been done */
3356int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3357{
d8bdc59f
LT		 3358 unsigned int nr;
3359 struct task_struct *reaper;
19fd4bb2 3360 struct tgid_iter iter;
b488893a 3361 struct pid_namespace *ns;
0499680a 3362 filldir_t __filldir;
1da177e4 3363
d8bdc59f
LT		 3364 if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
3365 goto out_no_task;
3366 nr = filp->f_pos - FIRST_PROCESS_ENTRY;
3367
3368 reaper = get_proc_task(filp->f_path.dentry->d_inode);
61a28784
EB		 3369 if (!reaper)
3370 goto out_no_task;
3371
7bcd6b0e 3372 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
c5141e6d 3373 const struct pid_entry *p = &proc_base_stuff[nr];
61a28784 3374 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
801199ce 3375 goto out;
1da177e4
LT		 3376 }
3377
b488893a 3378 ns = filp->f_dentry->d_sb->s_fs_info;
19fd4bb2
EB		 3379 iter.task = NULL;
3380 iter.tgid = filp->f_pos - TGID_OFFSET;
3381 for (iter = next_tgid(ns, iter);
3382 iter.task;
3383 iter.tgid += 1, iter = next_tgid(ns, iter)) {
0499680a
VK		 3384 if (has_pid_permissions(ns, iter.task, 2))
3385 __filldir = filldir;
3386 else
3387 __filldir = fake_filldir;
3388
19fd4bb2 3389 filp->f_pos = iter.tgid + TGID_OFFSET;
0499680a 3390 if (proc_pid_fill_cache(filp, dirent, __filldir, iter) < 0) {
19fd4bb2 3391 put_task_struct(iter.task);
0804ef4b 3392 goto out;
1da177e4 3393 }
0bc58a91 3394 }
0804ef4b
EB		 3395 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3396out:
61a28784
EB		 3397 put_task_struct(reaper);
3398out_no_task:
0bc58a91
EB		 3399 return 0;
3400}
1da177e4 3401
28a6d671
EB		 3402/*
3403 * Tasks
3404 */
c5141e6d 3405static const struct pid_entry tid_base_stuff[] = {
631f9c18 3406 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3407 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 3408 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
631f9c18
AD		 3409 REG("environ", S_IRUSR, proc_environ_operations),
3410 INF("auxv", S_IRUSR, proc_pid_auxv),
3411 ONE("status", S_IRUGO, proc_pid_status),
a9712bc1 3412 ONE("personality", S_IRUGO, proc_pid_personality),
3036e7b4 3413 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3414#ifdef CONFIG_SCHED_DEBUG
631f9c18 3415 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3416#endif
4614a696 3417 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3418#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
a9712bc1 3419 INF("syscall", S_IRUGO, proc_pid_syscall),
43ae34cb 3420#endif
631f9c18
AD		 3421 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3422 ONE("stat", S_IRUGO, proc_tid_stat),
3423 ONE("statm", S_IRUGO, proc_pid_statm),
b7643757 3424 REG("maps", S_IRUGO, proc_tid_maps_operations),
28a6d671 3425#ifdef CONFIG_NUMA
b7643757 3426 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
28a6d671 3427#endif
631f9c18
AD		 3428 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3429 LNK("cwd", proc_cwd_link),
3430 LNK("root", proc_root_link),
3431 LNK("exe", proc_exe_link),
3432 REG("mounts", S_IRUGO, proc_mounts_operations),
3433 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3434#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18 3435 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
b7643757 3436 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
ca6b0bf0 3437 REG("pagemap", S_IRUGO, proc_pagemap_operations),
28a6d671
EB		 3438#endif
3439#ifdef CONFIG_SECURITY
631f9c18 3440 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3441#endif
3442#ifdef CONFIG_KALLSYMS
631f9c18 3443 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3444#endif
2ec220e2 3445#ifdef CONFIG_STACKTRACE
a9712bc1 3446 ONE("stack", S_IRUGO, proc_pid_stack),
28a6d671
EB		 3447#endif
3448#ifdef CONFIG_SCHEDSTATS
631f9c18 3449 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3450#endif
9745512c 3451#ifdef CONFIG_LATENCYTOP
631f9c18 3452 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3453#endif
8793d854 3454#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3455 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3456#endif
3457#ifdef CONFIG_CGROUPS
631f9c18 3458 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3459#endif
631f9c18
AD		 3460 INF("oom_score", S_IRUGO, proc_oom_score),
3461 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3462 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3463#ifdef CONFIG_AUDITSYSCALL
631f9c18 3464 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
26ec3c64 3465 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3466#endif
f4f154fd 3467#ifdef CONFIG_FAULT_INJECTION
631f9c18 3468 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3469#endif
297c5d92 3470#ifdef CONFIG_TASK_IO_ACCOUNTING
1d1221f3 3471 INF("io", S_IRUSR, proc_tid_io_accounting),
297c5d92 3472#endif
f133ecca
CM		 3473#ifdef CONFIG_HARDWALL
3474 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3475#endif
22d917d8
EB		 3476#ifdef CONFIG_USER_NS
3477 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3478 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3479#endif
28a6d671
EB		 3480};
3481
3482static int proc_tid_base_readdir(struct file * filp,
3483 void * dirent, filldir_t filldir)
3484{
3485 return proc_pident_readdir(filp,dirent,filldir,
3486 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3487}
3488
3489static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3490 return proc_pident_lookup(dir, dentry,
3491 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3492}
3493
00977a59 3494static const struct file_operations proc_tid_base_operations = {
28a6d671
EB		 3495 .read = generic_read_dir,
3496 .readdir = proc_tid_base_readdir,
6038f373 3497 .llseek = default_llseek,
28a6d671
EB		 3498};
3499
c5ef1c42 3500static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3501 .lookup = proc_tid_base_lookup,
3502 .getattr = pid_getattr,
3503 .setattr = proc_setattr,
3504};
3505
444ceed8 3506static struct dentry *proc_task_instantiate(struct inode *dir,
c5141e6d 3507 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8
EB		 3508{
3509 struct dentry *error = ERR_PTR(-ENOENT);
3510 struct inode *inode;
61a28784 3511 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3512
3513 if (!inode)
3514 goto out;
3515 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3516 inode->i_op = &proc_tid_base_inode_operations;
3517 inode->i_fop = &proc_tid_base_operations;
3518 inode->i_flags|=S_IMMUTABLE;
aed54175 3519
bfe86848
MS		 3520 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff,
3521 ARRAY_SIZE(tid_base_stuff)));
444ceed8 3522
fb045adb 3523 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3524
3525 d_add(dentry, inode);
3526 /* Close the race of the process dying before we return the dentry */
3527 if (pid_revalidate(dentry, NULL))
3528 error = NULL;
3529out:
3530 return error;
3531}
3532
28a6d671
EB		 3533static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3534{
3535 struct dentry *result = ERR_PTR(-ENOENT);
3536 struct task_struct *task;
3537 struct task_struct *leader = get_proc_task(dir);
28a6d671 3538 unsigned tid;
b488893a 3539 struct pid_namespace *ns;
28a6d671
EB		 3540
3541 if (!leader)
3542 goto out_no_task;
3543
3544 tid = name_to_int(dentry);
3545 if (tid == ~0U)
3546 goto out;
3547
b488893a 3548 ns = dentry->d_sb->s_fs_info;
28a6d671 3549 rcu_read_lock();
b488893a 3550 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3551 if (task)
3552 get_task_struct(task);
3553 rcu_read_unlock();
3554 if (!task)
3555 goto out;
bac0abd6 3556 if (!same_thread_group(leader, task))
28a6d671
EB		 3557 goto out_drop_task;
3558
444ceed8 3559 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3560out_drop_task:
3561 put_task_struct(task);
3562out:
3563 put_task_struct(leader);
3564out_no_task:
3565 return result;
3566}
3567
0bc58a91
EB		 3568/*
3569 * Find the first tid of a thread group to return to user space.
3570 *
3571 * Usually this is just the thread group leader, but if the users
3572 * buffer was too small or there was a seek into the middle of the
3573 * directory we have more work todo.
3574 *
3575 * In the case of a short read we start with find_task_by_pid.
3576 *
3577 * In the case of a seek we start with the leader and walk nr
3578 * threads past it.
3579 */
cc288738 3580static struct task_struct *first_tid(struct task_struct *leader,
b488893a 3581 int tid, int nr, struct pid_namespace *ns)
0bc58a91 3582{
a872ff0c 3583 struct task_struct *pos;
1da177e4 3584
cc288738 3585 rcu_read_lock();
0bc58a91
EB		 3586 /* Attempt to start with the pid of a thread */
3587 if (tid && (nr > 0)) {
b488893a 3588 pos = find_task_by_pid_ns(tid, ns);
a872ff0c
ON		 3589 if (pos && (pos->group_leader == leader))
3590 goto found;
0bc58a91 3591 }
1da177e4 3592
0bc58a91 3593 /* If nr exceeds the number of threads there is nothing todo */
a872ff0c
ON		 3594 pos = NULL;
3595 if (nr && nr >= get_nr_threads(leader))
3596 goto out;
1da177e4 3597
a872ff0c
ON		 3598 /* If we haven't found our starting place yet start
3599 * with the leader and walk nr threads forward.
0bc58a91 3600 */
a872ff0c
ON		 3601 for (pos = leader; nr > 0; --nr) {
3602 pos = next_thread(pos);
3603 if (pos == leader) {
3604 pos = NULL;
3605 goto out;
3606 }
1da177e4 3607 }
a872ff0c
ON		 3608found:
3609 get_task_struct(pos);
3610out:
cc288738 3611 rcu_read_unlock();
0bc58a91
EB		 3612 return pos;
3613}
3614
3615/*
3616 * Find the next thread in the thread list.
3617 * Return NULL if there is an error or no next thread.
3618 *
3619 * The reference to the input task_struct is released.
3620 */
3621static struct task_struct *next_tid(struct task_struct *start)
3622{
c1df7fb8 3623 struct task_struct *pos = NULL;
cc288738 3624 rcu_read_lock();
c1df7fb8 3625 if (pid_alive(start)) {
0bc58a91 3626 pos = next_thread(start);
c1df7fb8
ON		 3627 if (thread_group_leader(pos))
3628 pos = NULL;
3629 else
3630 get_task_struct(pos);
3631 }
cc288738 3632 rcu_read_unlock();
0bc58a91
EB		 3633 put_task_struct(start);
3634 return pos;
1da177e4
LT		 3635}
3636
61a28784
EB		 3637static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3638 struct task_struct *task, int tid)
3639{
3640 char name[PROC_NUMBUF];
3641 int len = snprintf(name, sizeof(name), "%d", tid);
3642 return proc_fill_cache(filp, dirent, filldir, name, len,
3643 proc_task_instantiate, task, NULL);
3644}
3645
1da177e4
LT		 3646/* for the /proc/TGID/task/ directories */
3647static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3648{
2fddfeef 3649 struct dentry *dentry = filp->f_path.dentry;
1da177e4 3650 struct inode *inode = dentry->d_inode;
7d895244 3651 struct task_struct *leader = NULL;
0bc58a91 3652 struct task_struct *task;
1da177e4
LT		 3653 int retval = -ENOENT;
3654 ino_t ino;
0bc58a91 3655 int tid;
b488893a 3656 struct pid_namespace *ns;
1da177e4 3657
7d895244
GC		 3658 task = get_proc_task(inode);
3659 if (!task)
3660 goto out_no_task;
3661 rcu_read_lock();
3662 if (pid_alive(task)) {
3663 leader = task->group_leader;
3664 get_task_struct(leader);
3665 }
3666 rcu_read_unlock();
3667 put_task_struct(task);
99f89551
EB		 3668 if (!leader)
3669 goto out_no_task;
1da177e4
LT		 3670 retval = 0;
3671
ee568b25 3672 switch ((unsigned long)filp->f_pos) {
1da177e4
LT		 3673 case 0:
3674 ino = inode->i_ino;
ee6f779b 3675 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3676 goto out;
ee6f779b 3677 filp->f_pos++;
1da177e4
LT		 3678 /* fall through */
3679 case 1:
3680 ino = parent_ino(dentry);
ee6f779b 3681 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3682 goto out;
ee6f779b 3683 filp->f_pos++;
1da177e4
LT		 3684 /* fall through */
3685 }
3686
0bc58a91
EB		 3687 /* f_version caches the tgid value that the last readdir call couldn't
3688 * return. lseek aka telldir automagically resets f_version to 0.
3689 */
b488893a 3690 ns = filp->f_dentry->d_sb->s_fs_info;
2b47c361 3691 tid = (int)filp->f_version;
0bc58a91 3692 filp->f_version = 0;
ee6f779b 3693 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
0bc58a91 3694 task;
ee6f779b 3695 task = next_tid(task), filp->f_pos++) {
b488893a 3696 tid = task_pid_nr_ns(task, ns);
61a28784 3697 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
0bc58a91
EB		 3698 /* returning this tgid failed, save it as the first
3699 * pid for the next readir call */
2b47c361 3700 filp->f_version = (u64)tid;
0bc58a91 3701 put_task_struct(task);
1da177e4 3702 break;
0bc58a91 3703 }
1da177e4
LT		 3704 }
3705out:
99f89551
EB		 3706 put_task_struct(leader);
3707out_no_task:
1da177e4
LT		 3708 return retval;
3709}
6e66b52b
EB		 3710
3711static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3712{
3713 struct inode *inode = dentry->d_inode;
99f89551 3714 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3715 generic_fillattr(inode, stat);
3716
99f89551 3717 if (p) {
99f89551 3718 stat->nlink += get_nr_threads(p);
99f89551 3719 put_task_struct(p);
6e66b52b
EB		 3720 }
3721
3722 return 0;
3723}
28a6d671 3724
c5ef1c42 3725static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3726 .lookup = proc_task_lookup,
3727 .getattr = proc_task_getattr,
3728 .setattr = proc_setattr,
0499680a 3729 .permission = proc_pid_permission,
28a6d671
EB		 3730};
3731
00977a59 3732static const struct file_operations proc_task_operations = {
28a6d671
EB		 3733 .read = generic_read_dir,
3734 .readdir = proc_task_readdir,
6038f373 3735 .llseek = default_llseek,
28a6d671 3736};
Linux 6.x block layer and io_uring tree(s)