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selinux: Minor cleanups
[thirdparty/kernel/stable.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>
87ebdc00 76#include <linux/printk.h>
a424316c 77#include <linux/cgroup.h>
1da177e4
LT		 78#include <linux/cpuset.h>
79#include <linux/audit.h>
5addc5dd 80#include <linux/poll.h>
1651e14e 81#include <linux/nsproxy.h>
8ac773b4 82#include <linux/oom.h>
3cb4a0bb 83#include <linux/elf.h>
60347f67 84#include <linux/pid_namespace.h>
22d917d8 85#include <linux/user_namespace.h>
5ad4e53b 86#include <linux/fs_struct.h>
5a0e3ad6 87#include <linux/slab.h>
640708a2 88#include <linux/flex_array.h>
48f6a7a5 89#include <linux/posix-timers.h>
f133ecca
CM		 90#ifdef CONFIG_HARDWALL
91#include <asm/hardwall.h>
92#endif
43d2b113 93#include <trace/events/oom.h>
1da177e4 94#include "internal.h"
faf60af1 95#include "fd.h"
1da177e4 96
0f2fe20f
EB		 97/* NOTE:
98 * Implementing inode permission operations in /proc is almost
99 * certainly an error. Permission checks need to happen during
100 * each system call not at open time. The reason is that most of
101 * what we wish to check for permissions in /proc varies at runtime.
102 *
103 * The classic example of a problem is opening file descriptors
104 * in /proc for a task before it execs a suid executable.
105 */
106
1da177e4 107struct pid_entry {
cedbccab 108 const char *name;
c5141e6d 109 int len;
d161a13f 110 umode_t mode;
c5ef1c42 111 const struct inode_operations *iop;
00977a59 112 const struct file_operations *fop;
20cdc894 113 union proc_op op;
1da177e4
LT		 114};
115
61a28784 116#define NOD(NAME, MODE, IOP, FOP, OP) { \
20cdc894 117 .name = (NAME), \
c5141e6d 118 .len = sizeof(NAME) - 1, \
20cdc894
EB		 119 .mode = MODE, \
120 .iop = IOP, \
121 .fop = FOP, \
122 .op = OP, \
123}
124
631f9c18
AD		 125#define DIR(NAME, MODE, iops, fops) \
126 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
127#define LNK(NAME, get_link) \
61a28784 128 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
20cdc894 129 &proc_pid_link_inode_operations, NULL, \
631f9c18
AD		 130 { .proc_get_link = get_link } )
131#define REG(NAME, MODE, fops) \
132 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
631f9c18 133#define ONE(NAME, MODE, show) \
be614086
EB		 134 NOD(NAME, (S_IFREG|(MODE)), \
135 NULL, &proc_single_file_operations, \
631f9c18 136 { .proc_show = show } )
1da177e4 137
aed54175
VN		 138/*
139 * Count the number of hardlinks for the pid_entry table, excluding the .
140 * and .. links.
141 */
142static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
143 unsigned int n)
144{
145 unsigned int i;
146 unsigned int count;
147
148 count = 0;
149 for (i = 0; i < n; ++i) {
150 if (S_ISDIR(entries[i].mode))
151 ++count;
152 }
153
154 return count;
155}
156
f7ad3c6b 157static int get_task_root(struct task_struct *task, struct path *root)
1da177e4 158{
7c2c7d99
HD		 159 int result = -ENOENT;
160
0494f6ec 161 task_lock(task);
f7ad3c6b
MS		 162 if (task->fs) {
163 get_fs_root(task->fs, root);
7c2c7d99
HD		 164 result = 0;
165 }
0494f6ec 166 task_unlock(task);
7c2c7d99 167 return result;
0494f6ec
MS		 168}
169
7773fbc5 170static int proc_cwd_link(struct dentry *dentry, struct path *path)
0494f6ec 171{
2b0143b5 172 struct task_struct *task = get_proc_task(d_inode(dentry));
0494f6ec 173 int result = -ENOENT;
99f89551
EB		 174
175 if (task) {
f7ad3c6b
MS		 176 task_lock(task);
177 if (task->fs) {
178 get_fs_pwd(task->fs, path);
179 result = 0;
180 }
181 task_unlock(task);
99f89551
EB		 182 put_task_struct(task);
183 }
1da177e4
LT		 184 return result;
185}
186
7773fbc5 187static int proc_root_link(struct dentry *dentry, struct path *path)
1da177e4 188{
2b0143b5 189 struct task_struct *task = get_proc_task(d_inode(dentry));
1da177e4 190 int result = -ENOENT;
99f89551
EB		 191
192 if (task) {
f7ad3c6b 193 result = get_task_root(task, path);
99f89551
EB		 194 put_task_struct(task);
195 }
1da177e4
LT		 196 return result;
197}
198
c2c0bb44
AD		 199static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
200 size_t _count, loff_t *pos)
1da177e4 201{
c2c0bb44
AD		 202 struct task_struct *tsk;
203 struct mm_struct *mm;
204 char *page;
205 unsigned long count = _count;
206 unsigned long arg_start, arg_end, env_start, env_end;
207 unsigned long len1, len2, len;
208 unsigned long p;
209 char c;
210 ssize_t rv;
211
212 BUG_ON(*pos < 0);
213
214 tsk = get_proc_task(file_inode(file));
215 if (!tsk)
216 return -ESRCH;
217 mm = get_task_mm(tsk);
218 put_task_struct(tsk);
219 if (!mm)
220 return 0;
221 /* Check if process spawned far enough to have cmdline. */
222 if (!mm->env_end) {
223 rv = 0;
224 goto out_mmput;
225 }
226
227 page = (char *)__get_free_page(GFP_TEMPORARY);
228 if (!page) {
229 rv = -ENOMEM;
230 goto out_mmput;
231 }
232
233 down_read(&mm->mmap_sem);
234 arg_start = mm->arg_start;
235 arg_end = mm->arg_end;
236 env_start = mm->env_start;
237 env_end = mm->env_end;
238 up_read(&mm->mmap_sem);
239
240 BUG_ON(arg_start > arg_end);
241 BUG_ON(env_start > env_end);
242
243 len1 = arg_end - arg_start;
244 len2 = env_end - env_start;
245
3581d458
AD		 246 /* Empty ARGV. */
247 if (len1 == 0) {
248 rv = 0;
249 goto out_free_page;
250 }
2ca66ff7 251 /*
c2c0bb44
AD		 252 * Inherently racy -- command line shares address space
253 * with code and data.
2ca66ff7 254 */
6347e8d5 255 rv = access_remote_vm(mm, arg_end - 1, &c, 1, FOLL_FORCE);
c2c0bb44
AD		 256 if (rv <= 0)
257 goto out_free_page;
258
259 rv = 0;
260
261 if (c == '\0') {
262 /* Command line (set of strings) occupies whole ARGV. */
263 if (len1 <= *pos)
264 goto out_free_page;
265
266 p = arg_start + *pos;
267 len = len1 - *pos;
268 while (count > 0 && len > 0) {
269 unsigned int _count;
270 int nr_read;
271
272 _count = min3(count, len, PAGE_SIZE);
6347e8d5
LS		 273 nr_read = access_remote_vm(mm, p, page, _count,
274 FOLL_FORCE);
c2c0bb44
AD		 275 if (nr_read < 0)
276 rv = nr_read;
277 if (nr_read <= 0)
278 goto out_free_page;
279
280 if (copy_to_user(buf, page, nr_read)) {
281 rv = -EFAULT;
282 goto out_free_page;
283 }
284
285 p += nr_read;
286 len -= nr_read;
287 buf += nr_read;
288 count -= nr_read;
289 rv += nr_read;
290 }
291 } else {
292 /*
293 * Command line (1 string) occupies ARGV and maybe
294 * extends into ENVP.
295 */
296 if (len1 + len2 <= *pos)
297 goto skip_argv_envp;
298 if (len1 <= *pos)
299 goto skip_argv;
300
301 p = arg_start + *pos;
302 len = len1 - *pos;
303 while (count > 0 && len > 0) {
304 unsigned int _count, l;
305 int nr_read;
306 bool final;
307
308 _count = min3(count, len, PAGE_SIZE);
6347e8d5
LS		 309 nr_read = access_remote_vm(mm, p, page, _count,
310 FOLL_FORCE);
c2c0bb44
AD		 311 if (nr_read < 0)
312 rv = nr_read;
313 if (nr_read <= 0)
314 goto out_free_page;
315
316 /*
317 * Command line can be shorter than whole ARGV
318 * even if last "marker" byte says it is not.
319 */
320 final = false;
321 l = strnlen(page, nr_read);
322 if (l < nr_read) {
323 nr_read = l;
324 final = true;
325 }
326
327 if (copy_to_user(buf, page, nr_read)) {
328 rv = -EFAULT;
329 goto out_free_page;
330 }
331
332 p += nr_read;
333 len -= nr_read;
334 buf += nr_read;
335 count -= nr_read;
336 rv += nr_read;
337
338 if (final)
339 goto out_free_page;
340 }
341skip_argv:
342 /*
343 * Command line (1 string) occupies ARGV and
344 * extends into ENVP.
345 */
346 if (len1 <= *pos) {
347 p = env_start + *pos - len1;
348 len = len1 + len2 - *pos;
349 } else {
350 p = env_start;
351 len = len2;
352 }
353 while (count > 0 && len > 0) {
354 unsigned int _count, l;
355 int nr_read;
356 bool final;
357
358 _count = min3(count, len, PAGE_SIZE);
6347e8d5
LS		 359 nr_read = access_remote_vm(mm, p, page, _count,
360 FOLL_FORCE);
c2c0bb44
AD		 361 if (nr_read < 0)
362 rv = nr_read;
363 if (nr_read <= 0)
364 goto out_free_page;
365
366 /* Find EOS. */
367 final = false;
368 l = strnlen(page, nr_read);
369 if (l < nr_read) {
370 nr_read = l;
371 final = true;
372 }
373
374 if (copy_to_user(buf, page, nr_read)) {
375 rv = -EFAULT;
376 goto out_free_page;
377 }
378
379 p += nr_read;
380 len -= nr_read;
381 buf += nr_read;
382 count -= nr_read;
383 rv += nr_read;
384
385 if (final)
386 goto out_free_page;
387 }
388skip_argv_envp:
389 ;
390 }
391
392out_free_page:
393 free_page((unsigned long)page);
394out_mmput:
395 mmput(mm);
396 if (rv > 0)
397 *pos += rv;
398 return rv;
1da177e4
LT		 399}
400
c2c0bb44
AD		 401static const struct file_operations proc_pid_cmdline_ops = {
402 .read = proc_pid_cmdline_read,
403 .llseek = generic_file_llseek,
404};
405
1da177e4
LT		 406#ifdef CONFIG_KALLSYMS
407/*
408 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
409 * Returns the resolved symbol. If that fails, simply return the address.
410 */
edfcd606
AD		 411static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
412 struct pid *pid, struct task_struct *task)
1da177e4 413{
ffb45122 414 unsigned long wchan;
9281acea 415 char symname[KSYM_NAME_LEN];
1da177e4
LT		 416
417 wchan = get_wchan(task);
418
caaee623
JH		 419 if (wchan && ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)
420 && !lookup_symbol_name(wchan, symname))
25ce3191 421 seq_printf(m, "%s", symname);
b2f73922 422 else
1e92a61c 423 seq_putc(m, '0');
25ce3191
JP		 424
425 return 0;
1da177e4
LT		 426}
427#endif /* CONFIG_KALLSYMS */
428
a9712bc1
AV		 429static int lock_trace(struct task_struct *task)
430{
431 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
432 if (err)
433 return err;
caaee623 434 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
a9712bc1
AV		 435 mutex_unlock(&task->signal->cred_guard_mutex);
436 return -EPERM;
437 }
438 return 0;
439}
440
441static void unlock_trace(struct task_struct *task)
442{
443 mutex_unlock(&task->signal->cred_guard_mutex);
444}
445
2ec220e2
KC		 446#ifdef CONFIG_STACKTRACE
447
448#define MAX_STACK_TRACE_DEPTH 64
449
450static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
451 struct pid *pid, struct task_struct *task)
452{
453 struct stack_trace trace;
454 unsigned long *entries;
a9712bc1 455 int err;
2ec220e2
KC		 456 int i;
457
458 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
459 if (!entries)
460 return -ENOMEM;
461
462 trace.nr_entries = 0;
463 trace.max_entries = MAX_STACK_TRACE_DEPTH;
464 trace.entries = entries;
465 trace.skip = 0;
2ec220e2 466
a9712bc1
AV		 467 err = lock_trace(task);
468 if (!err) {
469 save_stack_trace_tsk(task, &trace);
470
471 for (i = 0; i < trace.nr_entries; i++) {
8b927d73 472 seq_printf(m, "[<%pK>] %pB\n",
a9712bc1
AV		 473 (void *)entries[i], (void *)entries[i]);
474 }
475 unlock_trace(task);
2ec220e2
KC		 476 }
477 kfree(entries);
478
a9712bc1 479 return err;
2ec220e2
KC		 480}
481#endif
482
5968cece 483#ifdef CONFIG_SCHED_INFO
1da177e4
LT		 484/*
485 * Provides /proc/PID/schedstat
486 */
f6e826ca
AD		 487static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
488 struct pid *pid, struct task_struct *task)
1da177e4 489{
5968cece
NR		 490 if (unlikely(!sched_info_on()))
491 seq_printf(m, "0 0 0\n");
492 else
493 seq_printf(m, "%llu %llu %lu\n",
25ce3191
JP		 494 (unsigned long long)task->se.sum_exec_runtime,
495 (unsigned long long)task->sched_info.run_delay,
496 task->sched_info.pcount);
497
498 return 0;
1da177e4
LT		 499}
500#endif
501
9745512c
AV		 502#ifdef CONFIG_LATENCYTOP
503static int lstats_show_proc(struct seq_file *m, void *v)
504{
505 int i;
13d77c37
HS		 506 struct inode *inode = m->private;
507 struct task_struct *task = get_proc_task(inode);
9745512c 508
13d77c37
HS		 509 if (!task)
510 return -ESRCH;
511 seq_puts(m, "Latency Top version : v0.1\n");
9745512c 512 for (i = 0; i < 32; i++) {
34e49d4f
JP		 513 struct latency_record *lr = &task->latency_record[i];
514 if (lr->backtrace[0]) {
9745512c 515 int q;
34e49d4f
JP		 516 seq_printf(m, "%i %li %li",
517 lr->count, lr->time, lr->max);
9745512c 518 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
34e49d4f
JP		 519 unsigned long bt = lr->backtrace[q];
520 if (!bt)
9745512c 521 break;
34e49d4f 522 if (bt == ULONG_MAX)
9745512c 523 break;
34e49d4f 524 seq_printf(m, " %ps", (void *)bt);
9745512c 525 }
9d6de12f 526 seq_putc(m, '\n');
9745512c
AV		 527 }
528
529 }
13d77c37 530 put_task_struct(task);
9745512c
AV		 531 return 0;
532}
533
534static int lstats_open(struct inode *inode, struct file *file)
535{
13d77c37 536 return single_open(file, lstats_show_proc, inode);
d6643d12
HS		 537}
538
9745512c
AV		 539static ssize_t lstats_write(struct file *file, const char __user *buf,
540 size_t count, loff_t *offs)
541{
496ad9aa 542 struct task_struct *task = get_proc_task(file_inode(file));
9745512c 543
13d77c37
HS		 544 if (!task)
545 return -ESRCH;
9745512c 546 clear_all_latency_tracing(task);
13d77c37 547 put_task_struct(task);
9745512c
AV		 548
549 return count;
550}
551
552static const struct file_operations proc_lstats_operations = {
553 .open = lstats_open,
554 .read = seq_read,
555 .write = lstats_write,
556 .llseek = seq_lseek,
13d77c37 557 .release = single_release,
9745512c
AV		 558};
559
560#endif
561
6ba51e37
AD		 562static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
563 struct pid *pid, struct task_struct *task)
1da177e4 564{
a7f638f9 565 unsigned long totalpages = totalram_pages + total_swap_pages;
b95c35e7 566 unsigned long points = 0;
1da177e4 567
ef419398
ON		 568 points = oom_badness(task, NULL, NULL, totalpages) *
569 1000 / totalpages;
25ce3191
JP		 570 seq_printf(m, "%lu\n", points);
571
572 return 0;
1da177e4
LT		 573}
574
d85f50d5 575struct limit_names {
cedbccab
AD		 576 const char *name;
577 const char *unit;
d85f50d5
NH		 578};
579
580static const struct limit_names lnames[RLIM_NLIMITS] = {
cff4edb5 581 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
d85f50d5
NH		 582 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
583 [RLIMIT_DATA] = {"Max data size", "bytes"},
584 [RLIMIT_STACK] = {"Max stack size", "bytes"},
585 [RLIMIT_CORE] = {"Max core file size", "bytes"},
586 [RLIMIT_RSS] = {"Max resident set", "bytes"},
587 [RLIMIT_NPROC] = {"Max processes", "processes"},
588 [RLIMIT_NOFILE] = {"Max open files", "files"},
589 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
590 [RLIMIT_AS] = {"Max address space", "bytes"},
591 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
592 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
593 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
594 [RLIMIT_NICE] = {"Max nice priority", NULL},
595 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
8808117c 596 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
d85f50d5
NH		 597};
598
599/* Display limits for a process */
1c963eb1
AD		 600static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
601 struct pid *pid, struct task_struct *task)
d85f50d5
NH		 602{
603 unsigned int i;
d85f50d5 604 unsigned long flags;
d85f50d5
NH		 605
606 struct rlimit rlim[RLIM_NLIMITS];
607
a6bebbc8 608 if (!lock_task_sighand(task, &flags))
d85f50d5 609 return 0;
d85f50d5
NH		 610 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
611 unlock_task_sighand(task, &flags);
d85f50d5
NH		 612
613 /*
614 * print the file header
615 */
1c963eb1 616 seq_printf(m, "%-25s %-20s %-20s %-10s\n",
25ce3191 617 "Limit", "Soft Limit", "Hard Limit", "Units");
d85f50d5
NH		 618
619 for (i = 0; i < RLIM_NLIMITS; i++) {
620 if (rlim[i].rlim_cur == RLIM_INFINITY)
1c963eb1 621 seq_printf(m, "%-25s %-20s ",
25ce3191 622 lnames[i].name, "unlimited");
d85f50d5 623 else
1c963eb1 624 seq_printf(m, "%-25s %-20lu ",
25ce3191 625 lnames[i].name, rlim[i].rlim_cur);
d85f50d5
NH		 626
627 if (rlim[i].rlim_max == RLIM_INFINITY)
1c963eb1 628 seq_printf(m, "%-20s ", "unlimited");
d85f50d5 629 else
1c963eb1 630 seq_printf(m, "%-20lu ", rlim[i].rlim_max);
d85f50d5
NH		 631
632 if (lnames[i].unit)
1c963eb1 633 seq_printf(m, "%-10s\n", lnames[i].unit);
d85f50d5 634 else
1c963eb1 635 seq_putc(m, '\n');
d85f50d5
NH		 636 }
637
1c963eb1 638 return 0;
d85f50d5
NH		 639}
640
ebcb6734 641#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
09d93bd6
AD		 642static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
643 struct pid *pid, struct task_struct *task)
ebcb6734
RM		 644{
645 long nr;
646 unsigned long args[6], sp, pc;
25ce3191
JP		 647 int res;
648
649 res = lock_trace(task);
a9712bc1
AV		 650 if (res)
651 return res;
ebcb6734
RM		 652
653 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
09d93bd6 654 seq_puts(m, "running\n");
a9712bc1 655 else if (nr < 0)
09d93bd6 656 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
a9712bc1 657 else
09d93bd6 658 seq_printf(m,
ebcb6734
RM		 659 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
660 nr,
661 args[0], args[1], args[2], args[3], args[4], args[5],
662 sp, pc);
a9712bc1 663 unlock_trace(task);
25ce3191
JP		 664
665 return 0;
ebcb6734
RM		 666}
667#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
668
1da177e4
LT		 669/************************************************************************/
670/* Here the fs part begins */
671/************************************************************************/
672
673/* permission checks */
778c1144 674static int proc_fd_access_allowed(struct inode *inode)
1da177e4 675{
778c1144
EB		 676 struct task_struct *task;
677 int allowed = 0;
df26c40e
EB		 678 /* Allow access to a task's file descriptors if it is us or we
679 * may use ptrace attach to the process and find out that
680 * information.
778c1144
EB		 681 */
682 task = get_proc_task(inode);
df26c40e 683 if (task) {
caaee623 684 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
778c1144 685 put_task_struct(task);
df26c40e 686 }
778c1144 687 return allowed;
1da177e4
LT		 688}
689
6b4e306a 690int proc_setattr(struct dentry *dentry, struct iattr *attr)
6d76fa58
LT		 691{
692 int error;
2b0143b5 693 struct inode *inode = d_inode(dentry);
6d76fa58
LT		 694
695 if (attr->ia_valid & ATTR_MODE)
696 return -EPERM;
697
31051c85 698 error = setattr_prepare(dentry, attr);
1025774c
CH		 699 if (error)
700 return error;
701
1025774c
CH		 702 setattr_copy(inode, attr);
703 mark_inode_dirty(inode);
704 return 0;
6d76fa58
LT		 705}
706
0499680a
VK		 707/*
708 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
709 * or euid/egid (for hide_pid_min=2)?
710 */
711static bool has_pid_permissions(struct pid_namespace *pid,
712 struct task_struct *task,
713 int hide_pid_min)
714{
715 if (pid->hide_pid < hide_pid_min)
716 return true;
717 if (in_group_p(pid->pid_gid))
718 return true;
caaee623 719 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
0499680a
VK		 720}
721
722
723static int proc_pid_permission(struct inode *inode, int mask)
724{
725 struct pid_namespace *pid = inode->i_sb->s_fs_info;
726 struct task_struct *task;
727 bool has_perms;
728
729 task = get_proc_task(inode);
a2ef990a
XF		 730 if (!task)
731 return -ESRCH;
0499680a
VK		 732 has_perms = has_pid_permissions(pid, task, 1);
733 put_task_struct(task);
734
735 if (!has_perms) {
736 if (pid->hide_pid == 2) {
737 /*
738 * Let's make getdents(), stat(), and open()
739 * consistent with each other. If a process
740 * may not stat() a file, it shouldn't be seen
741 * in procfs at all.
742 */
743 return -ENOENT;
744 }
745
746 return -EPERM;
747 }
748 return generic_permission(inode, mask);
749}
750
751
752
c5ef1c42 753static const struct inode_operations proc_def_inode_operations = {
6d76fa58
LT		 754 .setattr = proc_setattr,
755};
756
be614086
EB		 757static int proc_single_show(struct seq_file *m, void *v)
758{
759 struct inode *inode = m->private;
760 struct pid_namespace *ns;
761 struct pid *pid;
762 struct task_struct *task;
763 int ret;
764
765 ns = inode->i_sb->s_fs_info;
766 pid = proc_pid(inode);
767 task = get_pid_task(pid, PIDTYPE_PID);
768 if (!task)
769 return -ESRCH;
770
771 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
772
773 put_task_struct(task);
774 return ret;
775}
776
777static int proc_single_open(struct inode *inode, struct file *filp)
778{
c6a34058 779 return single_open(filp, proc_single_show, inode);
be614086
EB		 780}
781
782static const struct file_operations proc_single_file_operations = {
783 .open = proc_single_open,
784 .read = seq_read,
785 .llseek = seq_lseek,
786 .release = single_release,
787};
788
5381e169
ON		 789
790struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
1da177e4 791{
5381e169
ON		 792 struct task_struct *task = get_proc_task(inode);
793 struct mm_struct *mm = ERR_PTR(-ESRCH);
e268337d 794
5381e169 795 if (task) {
caaee623 796 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
5381e169 797 put_task_struct(task);
e268337d 798
5381e169
ON		 799 if (!IS_ERR_OR_NULL(mm)) {
800 /* ensure this mm_struct can't be freed */
801 atomic_inc(&mm->mm_count);
802 /* but do not pin its memory */
803 mmput(mm);
804 }
805 }
806
807 return mm;
808}
809
810static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
811{
812 struct mm_struct *mm = proc_mem_open(inode, mode);
e268337d
LT		 813
814 if (IS_ERR(mm))
815 return PTR_ERR(mm);
816
e268337d 817 file->private_data = mm;
1da177e4
LT		 818 return 0;
819}
820
b409e578
CW		 821static int mem_open(struct inode *inode, struct file *file)
822{
bc452b4b
DH		 823 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
824
825 /* OK to pass negative loff_t, we can catch out-of-range */
826 file->f_mode |= FMODE_UNSIGNED_OFFSET;
827
828 return ret;
b409e578
CW		 829}
830
572d34b9
ON		 831static ssize_t mem_rw(struct file *file, char __user *buf,
832 size_t count, loff_t *ppos, int write)
1da177e4 833{
e268337d 834 struct mm_struct *mm = file->private_data;
572d34b9
ON		 835 unsigned long addr = *ppos;
836 ssize_t copied;
1da177e4 837 char *page;
6347e8d5 838 unsigned int flags = FOLL_FORCE;
1da177e4 839
e268337d
LT		 840 if (!mm)
841 return 0;
99f89551 842
30cd8903
KM		 843 page = (char *)__get_free_page(GFP_TEMPORARY);
844 if (!page)
e268337d 845 return -ENOMEM;
1da177e4 846
f7ca54f4 847 copied = 0;
6d08f2c7
ON		 848 if (!atomic_inc_not_zero(&mm->mm_users))
849 goto free;
850
6347e8d5
LS		 851 if (write)
852 flags |= FOLL_WRITE;
853
1da177e4 854 while (count > 0) {
572d34b9 855 int this_len = min_t(int, count, PAGE_SIZE);
1da177e4 856
572d34b9 857 if (write && copy_from_user(page, buf, this_len)) {
1da177e4
LT		 858 copied = -EFAULT;
859 break;
860 }
572d34b9 861
6347e8d5 862 this_len = access_remote_vm(mm, addr, page, this_len, flags);
572d34b9 863 if (!this_len) {
1da177e4
LT		 864 if (!copied)
865 copied = -EIO;
866 break;
867 }
572d34b9
ON		 868
869 if (!write && copy_to_user(buf, page, this_len)) {
870 copied = -EFAULT;
871 break;
872 }
873
874 buf += this_len;
875 addr += this_len;
876 copied += this_len;
877 count -= this_len;
1da177e4 878 }
572d34b9 879 *ppos = addr;
30cd8903 880
6d08f2c7
ON		 881 mmput(mm);
882free:
30cd8903 883 free_page((unsigned long) page);
1da177e4
LT		 884 return copied;
885}
1da177e4 886
572d34b9
ON		 887static ssize_t mem_read(struct file *file, char __user *buf,
888 size_t count, loff_t *ppos)
889{
890 return mem_rw(file, buf, count, ppos, 0);
891}
892
893static ssize_t mem_write(struct file *file, const char __user *buf,
894 size_t count, loff_t *ppos)
895{
896 return mem_rw(file, (char __user*)buf, count, ppos, 1);
897}
898
85863e47 899loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 900{
901 switch (orig) {
902 case 0:
903 file->f_pos = offset;
904 break;
905 case 1:
906 file->f_pos += offset;
907 break;
908 default:
909 return -EINVAL;
910 }
911 force_successful_syscall_return();
912 return file->f_pos;
913}
914
e268337d
LT		 915static int mem_release(struct inode *inode, struct file *file)
916{
917 struct mm_struct *mm = file->private_data;
71879d3c 918 if (mm)
6d08f2c7 919 mmdrop(mm);
e268337d
LT		 920 return 0;
921}
922
00977a59 923static const struct file_operations proc_mem_operations = {
1da177e4
LT		 924 .llseek = mem_lseek,
925 .read = mem_read,
926 .write = mem_write,
927 .open = mem_open,
e268337d 928 .release = mem_release,
1da177e4
LT		 929};
930
b409e578
CW		 931static int environ_open(struct inode *inode, struct file *file)
932{
933 return __mem_open(inode, file, PTRACE_MODE_READ);
934}
935
315e28c8
JP		 936static ssize_t environ_read(struct file *file, char __user *buf,
937 size_t count, loff_t *ppos)
938{
315e28c8
JP		 939 char *page;
940 unsigned long src = *ppos;
b409e578
CW		 941 int ret = 0;
942 struct mm_struct *mm = file->private_data;
a3b609ef 943 unsigned long env_start, env_end;
315e28c8 944
8148a73c
MK		 945 /* Ensure the process spawned far enough to have an environment. */
946 if (!mm || !mm->env_end)
b409e578 947 return 0;
315e28c8 948
315e28c8
JP		 949 page = (char *)__get_free_page(GFP_TEMPORARY);
950 if (!page)
b409e578 951 return -ENOMEM;
315e28c8 952
d6f64b89 953 ret = 0;
b409e578
CW		 954 if (!atomic_inc_not_zero(&mm->mm_users))
955 goto free;
a3b609ef
MG		 956
957 down_read(&mm->mmap_sem);
958 env_start = mm->env_start;
959 env_end = mm->env_end;
960 up_read(&mm->mmap_sem);
961
315e28c8 962 while (count > 0) {
e8905ec2
DH		 963 size_t this_len, max_len;
964 int retval;
315e28c8 965
a3b609ef 966 if (src >= (env_end - env_start))
315e28c8
JP		 967 break;
968
a3b609ef 969 this_len = env_end - (env_start + src);
e8905ec2
DH		 970
971 max_len = min_t(size_t, PAGE_SIZE, count);
972 this_len = min(max_len, this_len);
315e28c8 973
a3b609ef 974 retval = access_remote_vm(mm, (env_start + src),
6347e8d5 975 page, this_len, FOLL_FORCE);
315e28c8
JP		 976
977 if (retval <= 0) {
978 ret = retval;
979 break;
980 }
981
982 if (copy_to_user(buf, page, retval)) {
983 ret = -EFAULT;
984 break;
985 }
986
987 ret += retval;
988 src += retval;
989 buf += retval;
990 count -= retval;
991 }
992 *ppos = src;
315e28c8 993 mmput(mm);
b409e578
CW		 994
995free:
315e28c8 996 free_page((unsigned long) page);
315e28c8
JP		 997 return ret;
998}
999
1000static const struct file_operations proc_environ_operations = {
b409e578 1001 .open = environ_open,
315e28c8 1002 .read = environ_read,
87df8424 1003 .llseek = generic_file_llseek,
b409e578 1004 .release = mem_release,
315e28c8
JP		 1005};
1006
c5317167
AV		 1007static int auxv_open(struct inode *inode, struct file *file)
1008{
1009 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
1010}
1011
1012static ssize_t auxv_read(struct file *file, char __user *buf,
1013 size_t count, loff_t *ppos)
1014{
1015 struct mm_struct *mm = file->private_data;
1016 unsigned int nwords = 0;
1017 do {
1018 nwords += 2;
1019 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1020 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,
1021 nwords * sizeof(mm->saved_auxv[0]));
1022}
1023
1024static const struct file_operations proc_auxv_operations = {
1025 .open = auxv_open,
1026 .read = auxv_read,
1027 .llseek = generic_file_llseek,
1028 .release = mem_release,
1029};
1030
fa0cbbf1
DR		 1031static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1032 loff_t *ppos)
1033{
496ad9aa 1034 struct task_struct *task = get_proc_task(file_inode(file));
fa0cbbf1
DR		 1035 char buffer[PROC_NUMBUF];
1036 int oom_adj = OOM_ADJUST_MIN;
1037 size_t len;
fa0cbbf1
DR		 1038
1039 if (!task)
1040 return -ESRCH;
f913da59
MH		 1041 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1042 oom_adj = OOM_ADJUST_MAX;
1043 else
1044 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1045 OOM_SCORE_ADJ_MAX;
fa0cbbf1
DR		 1046 put_task_struct(task);
1047 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1048 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1049}
1050
1d5f0acb
MH		 1051static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
1052{
1053 static DEFINE_MUTEX(oom_adj_mutex);
44a70ade 1054 struct mm_struct *mm = NULL;
1d5f0acb
MH		 1055 struct task_struct *task;
1056 int err = 0;
1057
1058 task = get_proc_task(file_inode(file));
1059 if (!task)
1060 return -ESRCH;
1061
1062 mutex_lock(&oom_adj_mutex);
1063 if (legacy) {
1064 if (oom_adj < task->signal->oom_score_adj &&
1065 !capable(CAP_SYS_RESOURCE)) {
1066 err = -EACCES;
1067 goto err_unlock;
1068 }
1069 /*
1070 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1071 * /proc/pid/oom_score_adj instead.
1072 */
1073 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1074 current->comm, task_pid_nr(current), task_pid_nr(task),
1075 task_pid_nr(task));
1076 } else {
1077 if ((short)oom_adj < task->signal->oom_score_adj_min &&
1078 !capable(CAP_SYS_RESOURCE)) {
1079 err = -EACCES;
1080 goto err_unlock;
1081 }
1082 }
1083
44a70ade
MH		 1084 /*
1085 * Make sure we will check other processes sharing the mm if this is
1086 * not vfrok which wants its own oom_score_adj.
1087 * pin the mm so it doesn't go away and get reused after task_unlock
1088 */
1089 if (!task->vfork_done) {
1090 struct task_struct *p = find_lock_task_mm(task);
1091
1092 if (p) {
1093 if (atomic_read(&p->mm->mm_users) > 1) {
1094 mm = p->mm;
1095 atomic_inc(&mm->mm_count);
1096 }
1097 task_unlock(p);
1098 }
1099 }
1100
1d5f0acb
MH		 1101 task->signal->oom_score_adj = oom_adj;
1102 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1103 task->signal->oom_score_adj_min = (short)oom_adj;
1104 trace_oom_score_adj_update(task);
44a70ade
MH		 1105
1106 if (mm) {
1107 struct task_struct *p;
1108
1109 rcu_read_lock();
1110 for_each_process(p) {
1111 if (same_thread_group(task, p))
1112 continue;
1113
1114 /* do not touch kernel threads or the global init */
1115 if (p->flags & PF_KTHREAD || is_global_init(p))
1116 continue;
1117
1118 task_lock(p);
1119 if (!p->vfork_done && process_shares_mm(p, mm)) {
1120 pr_info("updating oom_score_adj for %d (%s) from %d to %d because it shares mm with %d (%s). Report if this is unexpected.\n",
1121 task_pid_nr(p), p->comm,
1122 p->signal->oom_score_adj, oom_adj,
1123 task_pid_nr(task), task->comm);
1124 p->signal->oom_score_adj = oom_adj;
1125 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1126 p->signal->oom_score_adj_min = (short)oom_adj;
1127 }
1128 task_unlock(p);
1129 }
1130 rcu_read_unlock();
1131 mmdrop(mm);
1132 }
1d5f0acb
MH		 1133err_unlock:
1134 mutex_unlock(&oom_adj_mutex);
1135 put_task_struct(task);
1136 return err;
1137}
f913da59 1138
b72bdfa7
DR		 1139/*
1140 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1141 * kernels. The effective policy is defined by oom_score_adj, which has a
1142 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1143 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1144 * Processes that become oom disabled via oom_adj will still be oom disabled
1145 * with this implementation.
1146 *
1147 * oom_adj cannot be removed since existing userspace binaries use it.
1148 */
fa0cbbf1
DR		 1149static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1150 size_t count, loff_t *ppos)
1151{
fa0cbbf1
DR		 1152 char buffer[PROC_NUMBUF];
1153 int oom_adj;
fa0cbbf1
DR		 1154 int err;
1155
1156 memset(buffer, 0, sizeof(buffer));
1157 if (count > sizeof(buffer) - 1)
1158 count = sizeof(buffer) - 1;
1159 if (copy_from_user(buffer, buf, count)) {
1160 err = -EFAULT;
1161 goto out;
1162 }
1163
1164 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1165 if (err)
1166 goto out;
1167 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1168 oom_adj != OOM_DISABLE) {
1169 err = -EINVAL;
1170 goto out;
1171 }
1172
fa0cbbf1
DR		 1173 /*
1174 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1175 * value is always attainable.
1176 */
1177 if (oom_adj == OOM_ADJUST_MAX)
1178 oom_adj = OOM_SCORE_ADJ_MAX;
1179 else
1180 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1181
1d5f0acb 1182 err = __set_oom_adj(file, oom_adj, true);
fa0cbbf1
DR		 1183out:
1184 return err < 0 ? err : count;
1185}
1186
1187static const struct file_operations proc_oom_adj_operations = {
1188 .read = oom_adj_read,
1189 .write = oom_adj_write,
1190 .llseek = generic_file_llseek,
1191};
1192
a63d83f4
DR		 1193static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1194 size_t count, loff_t *ppos)
1195{
496ad9aa 1196 struct task_struct *task = get_proc_task(file_inode(file));
a63d83f4 1197 char buffer[PROC_NUMBUF];
a9c58b90 1198 short oom_score_adj = OOM_SCORE_ADJ_MIN;
a63d83f4
DR		 1199 size_t len;
1200
1201 if (!task)
1202 return -ESRCH;
f913da59 1203 oom_score_adj = task->signal->oom_score_adj;
a63d83f4 1204 put_task_struct(task);
a9c58b90 1205 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
a63d83f4
DR		 1206 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1207}
1208
1209static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1210 size_t count, loff_t *ppos)
1211{
a63d83f4 1212 char buffer[PROC_NUMBUF];
0a8cb8e3 1213 int oom_score_adj;
a63d83f4
DR		 1214 int err;
1215
1216 memset(buffer, 0, sizeof(buffer));
1217 if (count > sizeof(buffer) - 1)
1218 count = sizeof(buffer) - 1;
723548bf
DR		 1219 if (copy_from_user(buffer, buf, count)) {
1220 err = -EFAULT;
1221 goto out;
1222 }
a63d83f4 1223
0a8cb8e3 1224 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
a63d83f4 1225 if (err)
723548bf 1226 goto out;
a63d83f4 1227 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
723548bf
DR		 1228 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1229 err = -EINVAL;
1230 goto out;
1231 }
a63d83f4 1232
1d5f0acb 1233 err = __set_oom_adj(file, oom_score_adj, false);
723548bf
DR		 1234out:
1235 return err < 0 ? err : count;
a63d83f4
DR		 1236}
1237
1238static const struct file_operations proc_oom_score_adj_operations = {
1239 .read = oom_score_adj_read,
1240 .write = oom_score_adj_write,
6038f373 1241 .llseek = default_llseek,
a63d83f4
DR		 1242};
1243
1da177e4
LT		 1244#ifdef CONFIG_AUDITSYSCALL
1245#define TMPBUFLEN 21
1246static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1247 size_t count, loff_t *ppos)
1248{
496ad9aa 1249 struct inode * inode = file_inode(file);
99f89551 1250 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1251 ssize_t length;
1252 char tmpbuf[TMPBUFLEN];
1253
99f89551
EB		 1254 if (!task)
1255 return -ESRCH;
1da177e4 1256 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
e1760bd5
EB		 1257 from_kuid(file->f_cred->user_ns,
1258 audit_get_loginuid(task)));
99f89551 1259 put_task_struct(task);
1da177e4
LT		 1260 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1261}
1262
1263static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1264 size_t count, loff_t *ppos)
1265{
496ad9aa 1266 struct inode * inode = file_inode(file);
1da177e4 1267 uid_t loginuid;
e1760bd5 1268 kuid_t kloginuid;
774636e1 1269 int rv;
1da177e4 1270
7dc52157
PM		 1271 rcu_read_lock();
1272 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1273 rcu_read_unlock();
1da177e4 1274 return -EPERM;
7dc52157
PM		 1275 }
1276 rcu_read_unlock();
1da177e4 1277
1da177e4
LT		 1278 if (*ppos != 0) {
1279 /* No partial writes. */
1280 return -EINVAL;
1281 }
1da177e4 1282
774636e1
AD		 1283 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1284 if (rv < 0)
1285 return rv;
81407c84
EP		 1286
1287 /* is userspace tring to explicitly UNSET the loginuid? */
1288 if (loginuid == AUDIT_UID_UNSET) {
1289 kloginuid = INVALID_UID;
1290 } else {
1291 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
774636e1
AD		 1292 if (!uid_valid(kloginuid))
1293 return -EINVAL;
e1760bd5
EB		 1294 }
1295
774636e1
AD		 1296 rv = audit_set_loginuid(kloginuid);
1297 if (rv < 0)
1298 return rv;
1299 return count;
1da177e4
LT		 1300}
1301
00977a59 1302static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1303 .read = proc_loginuid_read,
1304 .write = proc_loginuid_write,
87df8424 1305 .llseek = generic_file_llseek,
1da177e4 1306};
1e0bd755
EP		 1307
1308static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1309 size_t count, loff_t *ppos)
1310{
496ad9aa 1311 struct inode * inode = file_inode(file);
1e0bd755
EP		 1312 struct task_struct *task = get_proc_task(inode);
1313 ssize_t length;
1314 char tmpbuf[TMPBUFLEN];
1315
1316 if (!task)
1317 return -ESRCH;
1318 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1319 audit_get_sessionid(task));
1320 put_task_struct(task);
1321 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1322}
1323
1324static const struct file_operations proc_sessionid_operations = {
1325 .read = proc_sessionid_read,
87df8424 1326 .llseek = generic_file_llseek,
1e0bd755 1327};
1da177e4
LT		 1328#endif
1329
f4f154fd
AM		 1330#ifdef CONFIG_FAULT_INJECTION
1331static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1332 size_t count, loff_t *ppos)
1333{
496ad9aa 1334 struct task_struct *task = get_proc_task(file_inode(file));
f4f154fd
AM		 1335 char buffer[PROC_NUMBUF];
1336 size_t len;
1337 int make_it_fail;
f4f154fd
AM		 1338
1339 if (!task)
1340 return -ESRCH;
1341 make_it_fail = task->make_it_fail;
1342 put_task_struct(task);
1343
1344 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1345
1346 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1347}
1348
1349static ssize_t proc_fault_inject_write(struct file * file,
1350 const char __user * buf, size_t count, loff_t *ppos)
1351{
1352 struct task_struct *task;
774636e1 1353 char buffer[PROC_NUMBUF];
f4f154fd 1354 int make_it_fail;
774636e1 1355 int rv;
f4f154fd
AM		 1356
1357 if (!capable(CAP_SYS_RESOURCE))
1358 return -EPERM;
1359 memset(buffer, 0, sizeof(buffer));
1360 if (count > sizeof(buffer) - 1)
1361 count = sizeof(buffer) - 1;
1362 if (copy_from_user(buffer, buf, count))
1363 return -EFAULT;
774636e1
AD		 1364 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1365 if (rv < 0)
1366 return rv;
16caed31
DJ		 1367 if (make_it_fail < 0 || make_it_fail > 1)
1368 return -EINVAL;
1369
496ad9aa 1370 task = get_proc_task(file_inode(file));
f4f154fd
AM		 1371 if (!task)
1372 return -ESRCH;
1373 task->make_it_fail = make_it_fail;
1374 put_task_struct(task);
cba8aafe
VL		 1375
1376 return count;
f4f154fd
AM		 1377}
1378
00977a59 1379static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1380 .read = proc_fault_inject_read,
1381 .write = proc_fault_inject_write,
87df8424 1382 .llseek = generic_file_llseek,
f4f154fd
AM		 1383};
1384#endif
1385
9745512c 1386
43ae34cb
IM		 1387#ifdef CONFIG_SCHED_DEBUG
1388/*
1389 * Print out various scheduling related per-task fields:
1390 */
1391static int sched_show(struct seq_file *m, void *v)
1392{
1393 struct inode *inode = m->private;
1394 struct task_struct *p;
1395
43ae34cb
IM		 1396 p = get_proc_task(inode);
1397 if (!p)
1398 return -ESRCH;
1399 proc_sched_show_task(p, m);
1400
1401 put_task_struct(p);
1402
1403 return 0;
1404}
1405
1406static ssize_t
1407sched_write(struct file *file, const char __user *buf,
1408 size_t count, loff_t *offset)
1409{
496ad9aa 1410 struct inode *inode = file_inode(file);
43ae34cb
IM		 1411 struct task_struct *p;
1412
43ae34cb
IM		 1413 p = get_proc_task(inode);
1414 if (!p)
1415 return -ESRCH;
1416 proc_sched_set_task(p);
1417
1418 put_task_struct(p);
1419
1420 return count;
1421}
1422
1423static int sched_open(struct inode *inode, struct file *filp)
1424{
c6a34058 1425 return single_open(filp, sched_show, inode);
43ae34cb
IM		 1426}
1427
1428static const struct file_operations proc_pid_sched_operations = {
1429 .open = sched_open,
1430 .read = seq_read,
1431 .write = sched_write,
1432 .llseek = seq_lseek,
5ea473a1 1433 .release = single_release,
43ae34cb
IM		 1434};
1435
1436#endif
1437
5091faa4
MG		 1438#ifdef CONFIG_SCHED_AUTOGROUP
1439/*
1440 * Print out autogroup related information:
1441 */
1442static int sched_autogroup_show(struct seq_file *m, void *v)
1443{
1444 struct inode *inode = m->private;
1445 struct task_struct *p;
1446
1447 p = get_proc_task(inode);
1448 if (!p)
1449 return -ESRCH;
1450 proc_sched_autogroup_show_task(p, m);
1451
1452 put_task_struct(p);
1453
1454 return 0;
1455}
1456
1457static ssize_t
1458sched_autogroup_write(struct file *file, const char __user *buf,
1459 size_t count, loff_t *offset)
1460{
496ad9aa 1461 struct inode *inode = file_inode(file);
5091faa4
MG		 1462 struct task_struct *p;
1463 char buffer[PROC_NUMBUF];
0a8cb8e3 1464 int nice;
5091faa4
MG		 1465 int err;
1466
1467 memset(buffer, 0, sizeof(buffer));
1468 if (count > sizeof(buffer) - 1)
1469 count = sizeof(buffer) - 1;
1470 if (copy_from_user(buffer, buf, count))
1471 return -EFAULT;
1472
0a8cb8e3
AD		 1473 err = kstrtoint(strstrip(buffer), 0, &nice);
1474 if (err < 0)
1475 return err;
5091faa4
MG		 1476
1477 p = get_proc_task(inode);
1478 if (!p)
1479 return -ESRCH;
1480
2e5b5b3a 1481 err = proc_sched_autogroup_set_nice(p, nice);
5091faa4
MG		 1482 if (err)
1483 count = err;
1484
1485 put_task_struct(p);
1486
1487 return count;
1488}
1489
1490static int sched_autogroup_open(struct inode *inode, struct file *filp)
1491{
1492 int ret;
1493
1494 ret = single_open(filp, sched_autogroup_show, NULL);
1495 if (!ret) {
1496 struct seq_file *m = filp->private_data;
1497
1498 m->private = inode;
1499 }
1500 return ret;
1501}
1502
1503static const struct file_operations proc_pid_sched_autogroup_operations = {
1504 .open = sched_autogroup_open,
1505 .read = seq_read,
1506 .write = sched_autogroup_write,
1507 .llseek = seq_lseek,
1508 .release = single_release,
1509};
1510
1511#endif /* CONFIG_SCHED_AUTOGROUP */
1512
4614a696
JS		 1513static ssize_t comm_write(struct file *file, const char __user *buf,
1514 size_t count, loff_t *offset)
1515{
496ad9aa 1516 struct inode *inode = file_inode(file);
4614a696
JS		 1517 struct task_struct *p;
1518 char buffer[TASK_COMM_LEN];
830e0fc9 1519 const size_t maxlen = sizeof(buffer) - 1;
4614a696
JS		 1520
1521 memset(buffer, 0, sizeof(buffer));
830e0fc9 1522 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
4614a696
JS		 1523 return -EFAULT;
1524
1525 p = get_proc_task(inode);
1526 if (!p)
1527 return -ESRCH;
1528
1529 if (same_thread_group(current, p))
1530 set_task_comm(p, buffer);
1531 else
1532 count = -EINVAL;
1533
1534 put_task_struct(p);
1535
1536 return count;
1537}
1538
1539static int comm_show(struct seq_file *m, void *v)
1540{
1541 struct inode *inode = m->private;
1542 struct task_struct *p;
1543
1544 p = get_proc_task(inode);
1545 if (!p)
1546 return -ESRCH;
1547
1548 task_lock(p);
1549 seq_printf(m, "%s\n", p->comm);
1550 task_unlock(p);
1551
1552 put_task_struct(p);
1553
1554 return 0;
1555}
1556
1557static int comm_open(struct inode *inode, struct file *filp)
1558{
c6a34058 1559 return single_open(filp, comm_show, inode);
4614a696
JS		 1560}
1561
1562static const struct file_operations proc_pid_set_comm_operations = {
1563 .open = comm_open,
1564 .read = seq_read,
1565 .write = comm_write,
1566 .llseek = seq_lseek,
1567 .release = single_release,
1568};
1569
7773fbc5 1570static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
925d1c40
MH		 1571{
1572 struct task_struct *task;
925d1c40
MH		 1573 struct file *exe_file;
1574
2b0143b5 1575 task = get_proc_task(d_inode(dentry));
925d1c40
MH		 1576 if (!task)
1577 return -ENOENT;
cd81a917 1578 exe_file = get_task_exe_file(task);
925d1c40 1579 put_task_struct(task);
925d1c40
MH		 1580 if (exe_file) {
1581 *exe_path = exe_file->f_path;
1582 path_get(&exe_file->f_path);
1583 fput(exe_file);
1584 return 0;
1585 } else
1586 return -ENOENT;
1587}
1588
6b255391 1589static const char *proc_pid_get_link(struct dentry *dentry,
fceef393
AV		 1590 struct inode *inode,
1591 struct delayed_call *done)
1da177e4 1592{
408ef013 1593 struct path path;
1da177e4
LT		 1594 int error = -EACCES;
1595
6b255391
AV		 1596 if (!dentry)
1597 return ERR_PTR(-ECHILD);
1598
778c1144
EB		 1599 /* Are we allowed to snoop on the tasks file descriptors? */
1600 if (!proc_fd_access_allowed(inode))
1da177e4 1601 goto out;
1da177e4 1602
408ef013
CH		 1603 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1604 if (error)
1605 goto out;
1606
6e77137b 1607 nd_jump_link(&path);
408ef013 1608 return NULL;
1da177e4 1609out:
008b150a 1610 return ERR_PTR(error);
1da177e4
LT		 1611}
1612
3dcd25f3 1613static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1614{
e12ba74d 1615 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1616 char *pathname;
1da177e4
LT		 1617 int len;
1618
1619 if (!tmp)
1620 return -ENOMEM;
0c28f287 1621
7b2a69ba 1622 pathname = d_path(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1623 len = PTR_ERR(pathname);
1624 if (IS_ERR(pathname))
1da177e4 1625 goto out;
3dcd25f3 1626 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1627
1628 if (len > buflen)
1629 len = buflen;
3dcd25f3 1630 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1631 len = -EFAULT;
1632 out:
1633 free_page((unsigned long)tmp);
1634 return len;
1635}
1636
1637static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1638{
1639 int error = -EACCES;
2b0143b5 1640 struct inode *inode = d_inode(dentry);
3dcd25f3 1641 struct path path;
1da177e4 1642
778c1144
EB		 1643 /* Are we allowed to snoop on the tasks file descriptors? */
1644 if (!proc_fd_access_allowed(inode))
1da177e4 1645 goto out;
1da177e4 1646
7773fbc5 1647 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1da177e4
LT		 1648 if (error)
1649 goto out;
1650
3dcd25f3
JB		 1651 error = do_proc_readlink(&path, buffer, buflen);
1652 path_put(&path);
1da177e4 1653out:
1da177e4
LT		 1654 return error;
1655}
1656
faf60af1 1657const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1658 .readlink = proc_pid_readlink,
6b255391 1659 .get_link = proc_pid_get_link,
6d76fa58 1660 .setattr = proc_setattr,
1da177e4
LT		 1661};
1662
28a6d671
EB		 1663
1664/* building an inode */
1665
6b4e306a 1666struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1667{
1668 struct inode * inode;
1669 struct proc_inode *ei;
c69e8d9c 1670 const struct cred *cred;
1da177e4 1671
28a6d671 1672 /* We need a new inode */
1da177e4 1673
28a6d671
EB		 1674 inode = new_inode(sb);
1675 if (!inode)
1676 goto out;
1677
1678 /* Common stuff */
1679 ei = PROC_I(inode);
85fe4025 1680 inode->i_ino = get_next_ino();
078cd827 1681 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
28a6d671
EB		 1682 inode->i_op = &proc_def_inode_operations;
1683
1684 /*
1685 * grab the reference to task.
1686 */
1a657f78 1687 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1688 if (!ei->pid)
1689 goto out_unlock;
1690
28a6d671 1691 if (task_dumpable(task)) {
c69e8d9c
DH		 1692 rcu_read_lock();
1693 cred = __task_cred(task);
1694 inode->i_uid = cred->euid;
1695 inode->i_gid = cred->egid;
1696 rcu_read_unlock();
1da177e4 1697 }
28a6d671
EB		 1698 security_task_to_inode(task, inode);
1699
1da177e4 1700out:
28a6d671
EB		 1701 return inode;
1702
1703out_unlock:
1704 iput(inode);
1705 return NULL;
1da177e4
LT		 1706}
1707
6b4e306a 1708int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1709{
2b0143b5 1710 struct inode *inode = d_inode(dentry);
28a6d671 1711 struct task_struct *task;
c69e8d9c 1712 const struct cred *cred;
0499680a 1713 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
c69e8d9c 1714
28a6d671 1715 generic_fillattr(inode, stat);
1da177e4 1716
28a6d671 1717 rcu_read_lock();
dcb0f222
EB		 1718 stat->uid = GLOBAL_ROOT_UID;
1719 stat->gid = GLOBAL_ROOT_GID;
28a6d671
EB		 1720 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1721 if (task) {
0499680a
VK		 1722 if (!has_pid_permissions(pid, task, 2)) {
1723 rcu_read_unlock();
1724 /*
1725 * This doesn't prevent learning whether PID exists,
1726 * it only makes getattr() consistent with readdir().
1727 */
1728 return -ENOENT;
1729 }
28a6d671
EB		 1730 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1731 task_dumpable(task)) {
c69e8d9c
DH		 1732 cred = __task_cred(task);
1733 stat->uid = cred->euid;
1734 stat->gid = cred->egid;
1da177e4
LT		 1735 }
1736 }
28a6d671 1737 rcu_read_unlock();
d6e71144 1738 return 0;
1da177e4
LT		 1739}
1740
1da177e4
LT		 1741/* dentry stuff */
1742
1743/*
1744 * Exceptional case: normally we are not allowed to unhash a busy
1745 * directory. In this case, however, we can do it - no aliasing problems
1746 * due to the way we treat inodes.
1747 *
1748 * Rewrite the inode's ownerships here because the owning task may have
1749 * performed a setuid(), etc.
99f89551
EB		 1750 *
1751 * Before the /proc/pid/status file was created the only way to read
1752 * the effective uid of a /process was to stat /proc/pid. Reading
1753 * /proc/pid/status is slow enough that procps and other packages
1754 * kept stating /proc/pid. To keep the rules in /proc simple I have
1755 * made this apply to all per process world readable and executable
1756 * directories.
1da177e4 1757 */
0b728e19 1758int pid_revalidate(struct dentry *dentry, unsigned int flags)
1da177e4 1759{
34286d66
NP		 1760 struct inode *inode;
1761 struct task_struct *task;
c69e8d9c
DH		 1762 const struct cred *cred;
1763
0b728e19 1764 if (flags & LOOKUP_RCU)
34286d66
NP		 1765 return -ECHILD;
1766
2b0143b5 1767 inode = d_inode(dentry);
34286d66
NP		 1768 task = get_proc_task(inode);
1769
99f89551
EB		 1770 if (task) {
1771 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1772 task_dumpable(task)) {
c69e8d9c
DH		 1773 rcu_read_lock();
1774 cred = __task_cred(task);
1775 inode->i_uid = cred->euid;
1776 inode->i_gid = cred->egid;
1777 rcu_read_unlock();
1da177e4 1778 } else {
dcb0f222
EB		 1779 inode->i_uid = GLOBAL_ROOT_UID;
1780 inode->i_gid = GLOBAL_ROOT_GID;
1da177e4 1781 }
9ee8ab9f 1782 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1783 security_task_to_inode(task, inode);
99f89551 1784 put_task_struct(task);
1da177e4
LT		 1785 return 1;
1786 }
1da177e4
LT		 1787 return 0;
1788}
1789
d855a4b7
ON		 1790static inline bool proc_inode_is_dead(struct inode *inode)
1791{
1792 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
1793}
1794
1dd704b6
DH		 1795int pid_delete_dentry(const struct dentry *dentry)
1796{
1797 /* Is the task we represent dead?
1798 * If so, then don't put the dentry on the lru list,
1799 * kill it immediately.
1800 */
2b0143b5 1801 return proc_inode_is_dead(d_inode(dentry));
1dd704b6
DH		 1802}
1803
6b4e306a 1804const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1805{
1806 .d_revalidate = pid_revalidate,
1807 .d_delete = pid_delete_dentry,
1808};
1809
1810/* Lookups */
1811
1c0d04c9
EB		 1812/*
1813 * Fill a directory entry.
1814 *
1815 * If possible create the dcache entry and derive our inode number and
1816 * file type from dcache entry.
1817 *
1818 * Since all of the proc inode numbers are dynamically generated, the inode
1819 * numbers do not exist until the inode is cache. This means creating the
1820 * the dcache entry in readdir is necessary to keep the inode numbers
1821 * reported by readdir in sync with the inode numbers reported
1822 * by stat.
1823 */
f0c3b509 1824bool proc_fill_cache(struct file *file, struct dir_context *ctx,
6b4e306a 1825 const char *name, int len,
c5141e6d 1826 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1827{
f0c3b509 1828 struct dentry *child, *dir = file->f_path.dentry;
1df98b8b 1829 struct qstr qname = QSTR_INIT(name, len);
61a28784 1830 struct inode *inode;
1df98b8b
AV		 1831 unsigned type;
1832 ino_t ino;
61a28784 1833
1df98b8b 1834 child = d_hash_and_lookup(dir, &qname);
61a28784 1835 if (!child) {
3781764b
AV		 1836 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
1837 child = d_alloc_parallel(dir, &qname, &wq);
1838 if (IS_ERR(child))
1df98b8b 1839 goto end_instantiate;
3781764b
AV		 1840 if (d_in_lookup(child)) {
1841 int err = instantiate(d_inode(dir), child, task, ptr);
1842 d_lookup_done(child);
1843 if (err < 0) {
1844 dput(child);
1845 goto end_instantiate;
1846 }
61a28784
EB		 1847 }
1848 }
2b0143b5 1849 inode = d_inode(child);
147ce699
AV		 1850 ino = inode->i_ino;
1851 type = inode->i_mode >> 12;
61a28784 1852 dput(child);
f0c3b509 1853 return dir_emit(ctx, name, len, ino, type);
1df98b8b
AV		 1854
1855end_instantiate:
1856 return dir_emit(ctx, name, len, 1, DT_UNKNOWN);
61a28784
EB		 1857}
1858
640708a2
PE		 1859/*
1860 * dname_to_vma_addr - maps a dentry name into two unsigned longs
1861 * which represent vma start and end addresses.
1862 */
1863static int dname_to_vma_addr(struct dentry *dentry,
1864 unsigned long *start, unsigned long *end)
1865{
1866 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
1867 return -EINVAL;
1868
1869 return 0;
1870}
1871
0b728e19 1872static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
640708a2
PE		 1873{
1874 unsigned long vm_start, vm_end;
1875 bool exact_vma_exists = false;
1876 struct mm_struct *mm = NULL;
1877 struct task_struct *task;
1878 const struct cred *cred;
1879 struct inode *inode;
1880 int status = 0;
1881
0b728e19 1882 if (flags & LOOKUP_RCU)
640708a2
PE		 1883 return -ECHILD;
1884
2b0143b5 1885 inode = d_inode(dentry);
640708a2
PE		 1886 task = get_proc_task(inode);
1887 if (!task)
1888 goto out_notask;
1889
caaee623 1890 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
2344bec7 1891 if (IS_ERR_OR_NULL(mm))
640708a2
PE		 1892 goto out;
1893
1894 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
1895 down_read(&mm->mmap_sem);
1896 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
1897 up_read(&mm->mmap_sem);
1898 }
1899
1900 mmput(mm);
1901
1902 if (exact_vma_exists) {
1903 if (task_dumpable(task)) {
1904 rcu_read_lock();
1905 cred = __task_cred(task);
1906 inode->i_uid = cred->euid;
1907 inode->i_gid = cred->egid;
1908 rcu_read_unlock();
1909 } else {
dcb0f222
EB		 1910 inode->i_uid = GLOBAL_ROOT_UID;
1911 inode->i_gid = GLOBAL_ROOT_GID;
640708a2
PE		 1912 }
1913 security_task_to_inode(task, inode);
1914 status = 1;
1915 }
1916
1917out:
1918 put_task_struct(task);
1919
1920out_notask:
640708a2
PE		 1921 return status;
1922}
1923
1924static const struct dentry_operations tid_map_files_dentry_operations = {
1925 .d_revalidate = map_files_d_revalidate,
1926 .d_delete = pid_delete_dentry,
1927};
1928
6b255391 1929static int map_files_get_link(struct dentry *dentry, struct path *path)
640708a2
PE		 1930{
1931 unsigned long vm_start, vm_end;
1932 struct vm_area_struct *vma;
1933 struct task_struct *task;
1934 struct mm_struct *mm;
1935 int rc;
1936
1937 rc = -ENOENT;
2b0143b5 1938 task = get_proc_task(d_inode(dentry));
640708a2
PE		 1939 if (!task)
1940 goto out;
1941
1942 mm = get_task_mm(task);
1943 put_task_struct(task);
1944 if (!mm)
1945 goto out;
1946
1947 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
1948 if (rc)
1949 goto out_mmput;
1950
70335abb 1951 rc = -ENOENT;
640708a2
PE		 1952 down_read(&mm->mmap_sem);
1953 vma = find_exact_vma(mm, vm_start, vm_end);
1954 if (vma && vma->vm_file) {
1955 *path = vma->vm_file->f_path;
1956 path_get(path);
1957 rc = 0;
1958 }
1959 up_read(&mm->mmap_sem);
1960
1961out_mmput:
1962 mmput(mm);
1963out:
1964 return rc;
1965}
1966
1967struct map_files_info {
7b540d06 1968 fmode_t mode;
640708a2
PE		 1969 unsigned long len;
1970 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
1971};
1972
bdb4d100
CO		 1973/*
1974 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the
1975 * symlinks may be used to bypass permissions on ancestor directories in the
1976 * path to the file in question.
1977 */
1978static const char *
6b255391 1979proc_map_files_get_link(struct dentry *dentry,
fceef393
AV		 1980 struct inode *inode,
1981 struct delayed_call *done)
bdb4d100
CO		 1982{
1983 if (!capable(CAP_SYS_ADMIN))
1984 return ERR_PTR(-EPERM);
1985
fceef393 1986 return proc_pid_get_link(dentry, inode, done);
bdb4d100
CO		 1987}
1988
1989/*
6b255391 1990 * Identical to proc_pid_link_inode_operations except for get_link()
bdb4d100
CO		 1991 */
1992static const struct inode_operations proc_map_files_link_inode_operations = {
1993 .readlink = proc_pid_readlink,
6b255391 1994 .get_link = proc_map_files_get_link,
bdb4d100
CO		 1995 .setattr = proc_setattr,
1996};
1997
c52a47ac 1998static int
640708a2
PE		 1999proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2000 struct task_struct *task, const void *ptr)
2001{
7b540d06 2002 fmode_t mode = (fmode_t)(unsigned long)ptr;
640708a2
PE		 2003 struct proc_inode *ei;
2004 struct inode *inode;
2005
640708a2
PE		 2006 inode = proc_pid_make_inode(dir->i_sb, task);
2007 if (!inode)
c52a47ac 2008 return -ENOENT;
640708a2
PE		 2009
2010 ei = PROC_I(inode);
6b255391 2011 ei->op.proc_get_link = map_files_get_link;
640708a2 2012
bdb4d100 2013 inode->i_op = &proc_map_files_link_inode_operations;
640708a2
PE		 2014 inode->i_size = 64;
2015 inode->i_mode = S_IFLNK;
2016
7b540d06 2017 if (mode & FMODE_READ)
640708a2 2018 inode->i_mode |= S_IRUSR;
7b540d06 2019 if (mode & FMODE_WRITE)
640708a2
PE		 2020 inode->i_mode |= S_IWUSR;
2021
2022 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2023 d_add(dentry, inode);
2024
c52a47ac 2025 return 0;
640708a2
PE		 2026}
2027
2028static struct dentry *proc_map_files_lookup(struct inode *dir,
00cd8dd3 2029 struct dentry *dentry, unsigned int flags)
640708a2
PE		 2030{
2031 unsigned long vm_start, vm_end;
2032 struct vm_area_struct *vma;
2033 struct task_struct *task;
c52a47ac 2034 int result;
640708a2
PE		 2035 struct mm_struct *mm;
2036
c52a47ac 2037 result = -ENOENT;
640708a2
PE		 2038 task = get_proc_task(dir);
2039 if (!task)
2040 goto out;
2041
c52a47ac 2042 result = -EACCES;
caaee623 2043 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
640708a2
PE		 2044 goto out_put_task;
2045
c52a47ac 2046 result = -ENOENT;
640708a2 2047 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
eb94cd96 2048 goto out_put_task;
640708a2
PE		 2049
2050 mm = get_task_mm(task);
2051 if (!mm)
eb94cd96 2052 goto out_put_task;
640708a2
PE		 2053
2054 down_read(&mm->mmap_sem);
2055 vma = find_exact_vma(mm, vm_start, vm_end);
2056 if (!vma)
2057 goto out_no_vma;
2058
05f56484
SK		 2059 if (vma->vm_file)
2060 result = proc_map_files_instantiate(dir, dentry, task,
2061 (void *)(unsigned long)vma->vm_file->f_mode);
640708a2
PE		 2062
2063out_no_vma:
2064 up_read(&mm->mmap_sem);
2065 mmput(mm);
640708a2
PE		 2066out_put_task:
2067 put_task_struct(task);
2068out:
c52a47ac 2069 return ERR_PTR(result);
640708a2
PE		 2070}
2071
2072static const struct inode_operations proc_map_files_inode_operations = {
2073 .lookup = proc_map_files_lookup,
2074 .permission = proc_fd_permission,
2075 .setattr = proc_setattr,
2076};
2077
2078static int
f0c3b509 2079proc_map_files_readdir(struct file *file, struct dir_context *ctx)
640708a2 2080{
640708a2
PE		 2081 struct vm_area_struct *vma;
2082 struct task_struct *task;
2083 struct mm_struct *mm;
f0c3b509
AV		 2084 unsigned long nr_files, pos, i;
2085 struct flex_array *fa = NULL;
2086 struct map_files_info info;
2087 struct map_files_info *p;
640708a2
PE		 2088 int ret;
2089
640708a2 2090 ret = -ENOENT;
f0c3b509 2091 task = get_proc_task(file_inode(file));
640708a2
PE		 2092 if (!task)
2093 goto out;
2094
2095 ret = -EACCES;
caaee623 2096 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
640708a2
PE		 2097 goto out_put_task;
2098
2099 ret = 0;
f0c3b509
AV		 2100 if (!dir_emit_dots(file, ctx))
2101 goto out_put_task;
640708a2 2102
f0c3b509
AV		 2103 mm = get_task_mm(task);
2104 if (!mm)
2105 goto out_put_task;
2106 down_read(&mm->mmap_sem);
640708a2 2107
f0c3b509 2108 nr_files = 0;
640708a2 2109
f0c3b509
AV		 2110 /*
2111 * We need two passes here:
2112 *
2113 * 1) Collect vmas of mapped files with mmap_sem taken
2114 * 2) Release mmap_sem and instantiate entries
2115 *
2116 * otherwise we get lockdep complained, since filldir()
2117 * routine might require mmap_sem taken in might_fault().
2118 */
640708a2 2119
f0c3b509
AV		 2120 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2121 if (vma->vm_file && ++pos > ctx->pos)
2122 nr_files++;
2123 }
2124
2125 if (nr_files) {
2126 fa = flex_array_alloc(sizeof(info), nr_files,
2127 GFP_KERNEL);
2128 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2129 GFP_KERNEL)) {
2130 ret = -ENOMEM;
2131 if (fa)
2132 flex_array_free(fa);
2133 up_read(&mm->mmap_sem);
2134 mmput(mm);
2135 goto out_put_task;
640708a2 2136 }
f0c3b509
AV		 2137 for (i = 0, vma = mm->mmap, pos = 2; vma;
2138 vma = vma->vm_next) {
2139 if (!vma->vm_file)
2140 continue;
2141 if (++pos <= ctx->pos)
2142 continue;
2143
2144 info.mode = vma->vm_file->f_mode;
2145 info.len = snprintf(info.name,
2146 sizeof(info.name), "%lx-%lx",
2147 vma->vm_start, vma->vm_end);
2148 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2149 BUG();
640708a2 2150 }
640708a2 2151 }
f0c3b509
AV		 2152 up_read(&mm->mmap_sem);
2153
2154 for (i = 0; i < nr_files; i++) {
2155 p = flex_array_get(fa, i);
2156 if (!proc_fill_cache(file, ctx,
2157 p->name, p->len,
2158 proc_map_files_instantiate,
2159 task,
2160 (void *)(unsigned long)p->mode))
2161 break;
2162 ctx->pos++;
640708a2 2163 }
f0c3b509
AV		 2164 if (fa)
2165 flex_array_free(fa);
2166 mmput(mm);
640708a2 2167
640708a2
PE		 2168out_put_task:
2169 put_task_struct(task);
2170out:
2171 return ret;
2172}
2173
2174static const struct file_operations proc_map_files_operations = {
2175 .read = generic_read_dir,
f50752ea
AV		 2176 .iterate_shared = proc_map_files_readdir,
2177 .llseek = generic_file_llseek,
640708a2
PE		 2178};
2179
b5946bea 2180#ifdef CONFIG_CHECKPOINT_RESTORE
48f6a7a5
PE		 2181struct timers_private {
2182 struct pid *pid;
2183 struct task_struct *task;
2184 struct sighand_struct *sighand;
57b8015e 2185 struct pid_namespace *ns;
48f6a7a5
PE		 2186 unsigned long flags;
2187};
2188
2189static void *timers_start(struct seq_file *m, loff_t *pos)
2190{
2191 struct timers_private *tp = m->private;
2192
2193 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2194 if (!tp->task)
2195 return ERR_PTR(-ESRCH);
2196
2197 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2198 if (!tp->sighand)
2199 return ERR_PTR(-ESRCH);
2200
2201 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2202}
2203
2204static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2205{
2206 struct timers_private *tp = m->private;
2207 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2208}
2209
2210static void timers_stop(struct seq_file *m, void *v)
2211{
2212 struct timers_private *tp = m->private;
2213
2214 if (tp->sighand) {
2215 unlock_task_sighand(tp->task, &tp->flags);
2216 tp->sighand = NULL;
2217 }
2218
2219 if (tp->task) {
2220 put_task_struct(tp->task);
2221 tp->task = NULL;
2222 }
2223}
2224
2225static int show_timer(struct seq_file *m, void *v)
2226{
2227 struct k_itimer *timer;
57b8015e
PE		 2228 struct timers_private *tp = m->private;
2229 int notify;
cedbccab 2230 static const char * const nstr[] = {
57b8015e
PE		 2231 [SIGEV_SIGNAL] = "signal",
2232 [SIGEV_NONE] = "none",
2233 [SIGEV_THREAD] = "thread",
2234 };
48f6a7a5
PE		 2235
2236 timer = list_entry((struct list_head *)v, struct k_itimer, list);
57b8015e
PE		 2237 notify = timer->it_sigev_notify;
2238
48f6a7a5 2239 seq_printf(m, "ID: %d\n", timer->it_id);
25ce3191
JP		 2240 seq_printf(m, "signal: %d/%p\n",
2241 timer->sigq->info.si_signo,
2242 timer->sigq->info.si_value.sival_ptr);
57b8015e 2243 seq_printf(m, "notify: %s/%s.%d\n",
25ce3191
JP		 2244 nstr[notify & ~SIGEV_THREAD_ID],
2245 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2246 pid_nr_ns(timer->it_pid, tp->ns));
15ef0298 2247 seq_printf(m, "ClockID: %d\n", timer->it_clock);
48f6a7a5
PE		 2248
2249 return 0;
2250}
2251
2252static const struct seq_operations proc_timers_seq_ops = {
2253 .start = timers_start,
2254 .next = timers_next,
2255 .stop = timers_stop,
2256 .show = show_timer,
2257};
2258
2259static int proc_timers_open(struct inode *inode, struct file *file)
2260{
2261 struct timers_private *tp;
2262
2263 tp = __seq_open_private(file, &proc_timers_seq_ops,
2264 sizeof(struct timers_private));
2265 if (!tp)
2266 return -ENOMEM;
2267
2268 tp->pid = proc_pid(inode);
57b8015e 2269 tp->ns = inode->i_sb->s_fs_info;
48f6a7a5
PE		 2270 return 0;
2271}
2272
2273static const struct file_operations proc_timers_operations = {
2274 .open = proc_timers_open,
2275 .read = seq_read,
2276 .llseek = seq_lseek,
2277 .release = seq_release_private,
2278};
b5946bea 2279#endif
640708a2 2280
5de23d43
JS		 2281static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2282 size_t count, loff_t *offset)
2283{
2284 struct inode *inode = file_inode(file);
2285 struct task_struct *p;
2286 u64 slack_ns;
2287 int err;
2288
2289 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2290 if (err < 0)
2291 return err;
2292
2293 p = get_proc_task(inode);
2294 if (!p)
2295 return -ESRCH;
2296
4b2bd5fe
JS		 2297 if (p != current) {
2298 if (!capable(CAP_SYS_NICE)) {
2299 count = -EPERM;
2300 goto out;
2301 }
5de23d43 2302
4b2bd5fe
JS		 2303 err = security_task_setscheduler(p);
2304 if (err) {
2305 count = err;
2306 goto out;
2307 }
904763e1
JS		 2308 }
2309
7abbaf94
JS		 2310 task_lock(p);
2311 if (slack_ns == 0)
2312 p->timer_slack_ns = p->default_timer_slack_ns;
2313 else
2314 p->timer_slack_ns = slack_ns;
2315 task_unlock(p);
2316
2317out:
5de23d43
JS		 2318 put_task_struct(p);
2319
2320 return count;
2321}
2322
2323static int timerslack_ns_show(struct seq_file *m, void *v)
2324{
2325 struct inode *inode = m->private;
2326 struct task_struct *p;
7abbaf94 2327 int err = 0;
5de23d43
JS		 2328
2329 p = get_proc_task(inode);
2330 if (!p)
2331 return -ESRCH;
2332
4b2bd5fe 2333 if (p != current) {
5de23d43 2334
4b2bd5fe
JS		 2335 if (!capable(CAP_SYS_NICE)) {
2336 err = -EPERM;
2337 goto out;
2338 }
2339 err = security_task_getscheduler(p);
2340 if (err)
2341 goto out;
2342 }
904763e1 2343
7abbaf94
JS		 2344 task_lock(p);
2345 seq_printf(m, "%llu\n", p->timer_slack_ns);
2346 task_unlock(p);
2347
2348out:
5de23d43
JS		 2349 put_task_struct(p);
2350
2351 return err;
2352}
2353
2354static int timerslack_ns_open(struct inode *inode, struct file *filp)
2355{
2356 return single_open(filp, timerslack_ns_show, inode);
2357}
2358
2359static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2360 .open = timerslack_ns_open,
2361 .read = seq_read,
2362 .write = timerslack_ns_write,
2363 .llseek = seq_lseek,
2364 .release = single_release,
2365};
2366
c52a47ac 2367static int proc_pident_instantiate(struct inode *dir,
c5141e6d 2368 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2369{
c5141e6d 2370 const struct pid_entry *p = ptr;
444ceed8
EB		 2371 struct inode *inode;
2372 struct proc_inode *ei;
444ceed8 2373
61a28784 2374 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2375 if (!inode)
2376 goto out;
2377
2378 ei = PROC_I(inode);
2379 inode->i_mode = p->mode;
2380 if (S_ISDIR(inode->i_mode))
bfe86848 2381 set_nlink(inode, 2); /* Use getattr to fix if necessary */
444ceed8
EB		 2382 if (p->iop)
2383 inode->i_op = p->iop;
2384 if (p->fop)
2385 inode->i_fop = p->fop;
2386 ei->op = p->op;
fb045adb 2387 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2388 d_add(dentry, inode);
2389 /* Close the race of the process dying before we return the dentry */
0b728e19 2390 if (pid_revalidate(dentry, 0))
c52a47ac 2391 return 0;
444ceed8 2392out:
c52a47ac 2393 return -ENOENT;
444ceed8
EB		 2394}
2395
1da177e4
LT		 2396static struct dentry *proc_pident_lookup(struct inode *dir,
2397 struct dentry *dentry,
c5141e6d 2398 const struct pid_entry *ents,
7bcd6b0e 2399 unsigned int nents)
1da177e4 2400{
c52a47ac 2401 int error;
99f89551 2402 struct task_struct *task = get_proc_task(dir);
c5141e6d 2403 const struct pid_entry *p, *last;
1da177e4 2404
c52a47ac 2405 error = -ENOENT;
1da177e4 2406
99f89551
EB		 2407 if (!task)
2408 goto out_no_task;
1da177e4 2409
20cdc894
EB		 2410 /*
2411 * Yes, it does not scale. And it should not. Don't add
2412 * new entries into /proc/<tgid>/ without very good reasons.
2413 */
7bcd6b0e
EB		 2414 last = &ents[nents - 1];
2415 for (p = ents; p <= last; p++) {
1da177e4
LT		 2416 if (p->len != dentry->d_name.len)
2417 continue;
2418 if (!memcmp(dentry->d_name.name, p->name, p->len))
2419 break;
2420 }
7bcd6b0e 2421 if (p > last)
1da177e4
LT		 2422 goto out;
2423
444ceed8 2424 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2425out:
99f89551
EB		 2426 put_task_struct(task);
2427out_no_task:
c52a47ac 2428 return ERR_PTR(error);
1da177e4
LT		 2429}
2430
f0c3b509 2431static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
c5141e6d 2432 const struct pid_entry *ents, unsigned int nents)
28a6d671 2433{
f0c3b509
AV		 2434 struct task_struct *task = get_proc_task(file_inode(file));
2435 const struct pid_entry *p;
28a6d671 2436
28a6d671 2437 if (!task)
f0c3b509 2438 return -ENOENT;
28a6d671 2439
f0c3b509
AV		 2440 if (!dir_emit_dots(file, ctx))
2441 goto out;
2442
2443 if (ctx->pos >= nents + 2)
2444 goto out;
28a6d671 2445
f0c3b509
AV		 2446 for (p = ents + (ctx->pos - 2); p <= ents + nents - 1; p++) {
2447 if (!proc_fill_cache(file, ctx, p->name, p->len,
2448 proc_pident_instantiate, task, p))
2449 break;
2450 ctx->pos++;
2451 }
28a6d671 2452out:
61a28784 2453 put_task_struct(task);
f0c3b509 2454 return 0;
1da177e4
LT		 2455}
2456
28a6d671
EB		 2457#ifdef CONFIG_SECURITY
2458static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2459 size_t count, loff_t *ppos)
2460{
496ad9aa 2461 struct inode * inode = file_inode(file);
04ff9708 2462 char *p = NULL;
28a6d671
EB		 2463 ssize_t length;
2464 struct task_struct *task = get_proc_task(inode);
2465
28a6d671 2466 if (!task)
04ff9708 2467 return -ESRCH;
28a6d671
EB		 2468
2469 length = security_getprocattr(task,
2fddfeef 2470 (char*)file->f_path.dentry->d_name.name,
04ff9708 2471 &p);
28a6d671 2472 put_task_struct(task);
04ff9708
AV		 2473 if (length > 0)
2474 length = simple_read_from_buffer(buf, count, ppos, p, length);
2475 kfree(p);
28a6d671 2476 return length;
1da177e4
LT		 2477}
2478
28a6d671
EB		 2479static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2480 size_t count, loff_t *ppos)
2481{
496ad9aa 2482 struct inode * inode = file_inode(file);
bb646cdb 2483 void *page;
28a6d671
EB		 2484 ssize_t length;
2485 struct task_struct *task = get_proc_task(inode);
2486
2487 length = -ESRCH;
2488 if (!task)
2489 goto out_no_task;
2490 if (count > PAGE_SIZE)
2491 count = PAGE_SIZE;
2492
2493 /* No partial writes. */
2494 length = -EINVAL;
2495 if (*ppos != 0)
2496 goto out;
2497
bb646cdb
AV		 2498 page = memdup_user(buf, count);
2499 if (IS_ERR(page)) {
2500 length = PTR_ERR(page);
28a6d671 2501 goto out;
bb646cdb 2502 }
28a6d671 2503
107db7c7 2504 /* Guard against adverse ptrace interaction */
9b1bf12d 2505 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2506 if (length < 0)
2507 goto out_free;
2508
28a6d671 2509 length = security_setprocattr(task,
2fddfeef 2510 (char*)file->f_path.dentry->d_name.name,
bb646cdb 2511 page, count);
9b1bf12d 2512 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671 2513out_free:
bb646cdb 2514 kfree(page);
28a6d671
EB		 2515out:
2516 put_task_struct(task);
2517out_no_task:
2518 return length;
2519}
2520
00977a59 2521static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2522 .read = proc_pid_attr_read,
2523 .write = proc_pid_attr_write,
87df8424 2524 .llseek = generic_file_llseek,
28a6d671
EB		 2525};
2526
c5141e6d 2527static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2528 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2529 REG("prev", S_IRUGO, proc_pid_attr_operations),
2530 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2531 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2532 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2533 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2534};
2535
f0c3b509 2536static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
28a6d671 2537{
f0c3b509
AV		 2538 return proc_pident_readdir(file, ctx,
2539 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2540}
2541
00977a59 2542static const struct file_operations proc_attr_dir_operations = {
1da177e4 2543 .read = generic_read_dir,
f50752ea
AV		 2544 .iterate_shared = proc_attr_dir_readdir,
2545 .llseek = generic_file_llseek,
1da177e4
LT		 2546};
2547
72d9dcfc 2548static struct dentry *proc_attr_dir_lookup(struct inode *dir,
00cd8dd3 2549 struct dentry *dentry, unsigned int flags)
28a6d671 2550{
7bcd6b0e
EB		 2551 return proc_pident_lookup(dir, dentry,
2552 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2553}
2554
c5ef1c42 2555static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2556 .lookup = proc_attr_dir_lookup,
99f89551 2557 .getattr = pid_getattr,
6d76fa58 2558 .setattr = proc_setattr,
1da177e4
LT		 2559};
2560
28a6d671
EB		 2561#endif
2562
698ba7b5 2563#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2564static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2565 size_t count, loff_t *ppos)
2566{
496ad9aa 2567 struct task_struct *task = get_proc_task(file_inode(file));
3cb4a0bb
KH		 2568 struct mm_struct *mm;
2569 char buffer[PROC_NUMBUF];
2570 size_t len;
2571 int ret;
2572
2573 if (!task)
2574 return -ESRCH;
2575
2576 ret = 0;
2577 mm = get_task_mm(task);
2578 if (mm) {
2579 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2580 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2581 MMF_DUMP_FILTER_SHIFT));
2582 mmput(mm);
2583 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2584 }
2585
2586 put_task_struct(task);
2587
2588 return ret;
2589}
2590
2591static ssize_t proc_coredump_filter_write(struct file *file,
2592 const char __user *buf,
2593 size_t count,
2594 loff_t *ppos)
2595{
2596 struct task_struct *task;
2597 struct mm_struct *mm;
3cb4a0bb
KH		 2598 unsigned int val;
2599 int ret;
2600 int i;
2601 unsigned long mask;
2602
774636e1
AD		 2603 ret = kstrtouint_from_user(buf, count, 0, &val);
2604 if (ret < 0)
2605 return ret;
3cb4a0bb
KH		 2606
2607 ret = -ESRCH;
496ad9aa 2608 task = get_proc_task(file_inode(file));
3cb4a0bb
KH		 2609 if (!task)
2610 goto out_no_task;
2611
3cb4a0bb
KH		 2612 mm = get_task_mm(task);
2613 if (!mm)
2614 goto out_no_mm;
41a0c249 2615 ret = 0;
3cb4a0bb
KH		 2616
2617 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2618 if (val & mask)
2619 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2620 else
2621 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2622 }
2623
2624 mmput(mm);
2625 out_no_mm:
2626 put_task_struct(task);
2627 out_no_task:
774636e1
AD		 2628 if (ret < 0)
2629 return ret;
2630 return count;
3cb4a0bb
KH		 2631}
2632
2633static const struct file_operations proc_coredump_filter_operations = {
2634 .read = proc_coredump_filter_read,
2635 .write = proc_coredump_filter_write,
87df8424 2636 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2637};
2638#endif
2639
aba76fdb 2640#ifdef CONFIG_TASK_IO_ACCOUNTING
19aadc98 2641static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
297c5d92 2642{
940389b8 2643 struct task_io_accounting acct = task->ioac;
5995477a 2644 unsigned long flags;
293eb1e7 2645 int result;
5995477a 2646
293eb1e7
VK		 2647 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2648 if (result)
2649 return result;
2650
caaee623 2651 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
293eb1e7
VK		 2652 result = -EACCES;
2653 goto out_unlock;
2654 }
1d1221f3 2655
5995477a
AR		 2656 if (whole && lock_task_sighand(task, &flags)) {
2657 struct task_struct *t = task;
2658
2659 task_io_accounting_add(&acct, &task->signal->ioac);
2660 while_each_thread(task, t)
2661 task_io_accounting_add(&acct, &t->ioac);
2662
2663 unlock_task_sighand(task, &flags);
297c5d92 2664 }
25ce3191
JP		 2665 seq_printf(m,
2666 "rchar: %llu\n"
2667 "wchar: %llu\n"
2668 "syscr: %llu\n"
2669 "syscw: %llu\n"
2670 "read_bytes: %llu\n"
2671 "write_bytes: %llu\n"
2672 "cancelled_write_bytes: %llu\n",
2673 (unsigned long long)acct.rchar,
2674 (unsigned long long)acct.wchar,
2675 (unsigned long long)acct.syscr,
2676 (unsigned long long)acct.syscw,
2677 (unsigned long long)acct.read_bytes,
2678 (unsigned long long)acct.write_bytes,
2679 (unsigned long long)acct.cancelled_write_bytes);
2680 result = 0;
2681
293eb1e7
VK		 2682out_unlock:
2683 mutex_unlock(&task->signal->cred_guard_mutex);
2684 return result;
297c5d92
AR		 2685}
2686
19aadc98
AD		 2687static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2688 struct pid *pid, struct task_struct *task)
297c5d92 2689{
19aadc98 2690 return do_io_accounting(task, m, 0);
aba76fdb 2691}
297c5d92 2692
19aadc98
AD		 2693static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2694 struct pid *pid, struct task_struct *task)
297c5d92 2695{
19aadc98 2696 return do_io_accounting(task, m, 1);
297c5d92
AR		 2697}
2698#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2699
22d917d8
EB		 2700#ifdef CONFIG_USER_NS
2701static int proc_id_map_open(struct inode *inode, struct file *file,
ccf94f1b 2702 const struct seq_operations *seq_ops)
22d917d8
EB		 2703{
2704 struct user_namespace *ns = NULL;
2705 struct task_struct *task;
2706 struct seq_file *seq;
2707 int ret = -EINVAL;
2708
2709 task = get_proc_task(inode);
2710 if (task) {
2711 rcu_read_lock();
2712 ns = get_user_ns(task_cred_xxx(task, user_ns));
2713 rcu_read_unlock();
2714 put_task_struct(task);
2715 }
2716 if (!ns)
2717 goto err;
2718
2719 ret = seq_open(file, seq_ops);
2720 if (ret)
2721 goto err_put_ns;
2722
2723 seq = file->private_data;
2724 seq->private = ns;
2725
2726 return 0;
2727err_put_ns:
2728 put_user_ns(ns);
2729err:
2730 return ret;
2731}
2732
2733static int proc_id_map_release(struct inode *inode, struct file *file)
2734{
2735 struct seq_file *seq = file->private_data;
2736 struct user_namespace *ns = seq->private;
2737 put_user_ns(ns);
2738 return seq_release(inode, file);
2739}
2740
2741static int proc_uid_map_open(struct inode *inode, struct file *file)
2742{
2743 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2744}
2745
2746static int proc_gid_map_open(struct inode *inode, struct file *file)
2747{
2748 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2749}
2750
f76d207a
EB		 2751static int proc_projid_map_open(struct inode *inode, struct file *file)
2752{
2753 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
2754}
2755
22d917d8
EB		 2756static const struct file_operations proc_uid_map_operations = {
2757 .open = proc_uid_map_open,
2758 .write = proc_uid_map_write,
2759 .read = seq_read,
2760 .llseek = seq_lseek,
2761 .release = proc_id_map_release,
2762};
2763
2764static const struct file_operations proc_gid_map_operations = {
2765 .open = proc_gid_map_open,
2766 .write = proc_gid_map_write,
2767 .read = seq_read,
2768 .llseek = seq_lseek,
2769 .release = proc_id_map_release,
2770};
f76d207a
EB		 2771
2772static const struct file_operations proc_projid_map_operations = {
2773 .open = proc_projid_map_open,
2774 .write = proc_projid_map_write,
2775 .read = seq_read,
2776 .llseek = seq_lseek,
2777 .release = proc_id_map_release,
2778};
9cc46516
EB		 2779
2780static int proc_setgroups_open(struct inode *inode, struct file *file)
2781{
2782 struct user_namespace *ns = NULL;
2783 struct task_struct *task;
2784 int ret;
2785
2786 ret = -ESRCH;
2787 task = get_proc_task(inode);
2788 if (task) {
2789 rcu_read_lock();
2790 ns = get_user_ns(task_cred_xxx(task, user_ns));
2791 rcu_read_unlock();
2792 put_task_struct(task);
2793 }
2794 if (!ns)
2795 goto err;
2796
2797 if (file->f_mode & FMODE_WRITE) {
2798 ret = -EACCES;
2799 if (!ns_capable(ns, CAP_SYS_ADMIN))
2800 goto err_put_ns;
2801 }
2802
2803 ret = single_open(file, &proc_setgroups_show, ns);
2804 if (ret)
2805 goto err_put_ns;
2806
2807 return 0;
2808err_put_ns:
2809 put_user_ns(ns);
2810err:
2811 return ret;
2812}
2813
2814static int proc_setgroups_release(struct inode *inode, struct file *file)
2815{
2816 struct seq_file *seq = file->private_data;
2817 struct user_namespace *ns = seq->private;
2818 int ret = single_release(inode, file);
2819 put_user_ns(ns);
2820 return ret;
2821}
2822
2823static const struct file_operations proc_setgroups_operations = {
2824 .open = proc_setgroups_open,
2825 .write = proc_setgroups_write,
2826 .read = seq_read,
2827 .llseek = seq_lseek,
2828 .release = proc_setgroups_release,
2829};
22d917d8
EB		 2830#endif /* CONFIG_USER_NS */
2831
47830723
KC		 2832static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2833 struct pid *pid, struct task_struct *task)
2834{
a9712bc1
AV		 2835 int err = lock_trace(task);
2836 if (!err) {
2837 seq_printf(m, "%08x\n", task->personality);
2838 unlock_trace(task);
2839 }
2840 return err;
47830723
KC		 2841}
2842
28a6d671
EB		 2843/*
2844 * Thread groups
2845 */
00977a59 2846static const struct file_operations proc_task_operations;
c5ef1c42 2847static const struct inode_operations proc_task_inode_operations;
20cdc894 2848
c5141e6d 2849static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2850 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2851 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
640708a2 2852 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
631f9c18 2853 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 2854 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
b2211a36 2855#ifdef CONFIG_NET
631f9c18 2856 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 2857#endif
631f9c18 2858 REG("environ", S_IRUSR, proc_environ_operations),
c5317167 2859 REG("auxv", S_IRUSR, proc_auxv_operations),
631f9c18 2860 ONE("status", S_IRUGO, proc_pid_status),
35a35046 2861 ONE("personality", S_IRUSR, proc_pid_personality),
1c963eb1 2862 ONE("limits", S_IRUGO, proc_pid_limits),
43ae34cb 2863#ifdef CONFIG_SCHED_DEBUG
631f9c18 2864 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
5091faa4
MG		 2865#endif
2866#ifdef CONFIG_SCHED_AUTOGROUP
2867 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
ebcb6734 2868#endif
4614a696 2869 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 2870#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
09d93bd6 2871 ONE("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 2872#endif
c2c0bb44 2873 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
631f9c18
AD		 2874 ONE("stat", S_IRUGO, proc_tgid_stat),
2875 ONE("statm", S_IRUGO, proc_pid_statm),
b7643757 2876 REG("maps", S_IRUGO, proc_pid_maps_operations),
28a6d671 2877#ifdef CONFIG_NUMA
b7643757 2878 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
28a6d671 2879#endif
631f9c18
AD		 2880 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2881 LNK("cwd", proc_cwd_link),
2882 LNK("root", proc_root_link),
2883 LNK("exe", proc_exe_link),
2884 REG("mounts", S_IRUGO, proc_mounts_operations),
2885 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2886 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 2887#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18 2888 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
b7643757 2889 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
32ed74a4 2890 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 2891#endif
2892#ifdef CONFIG_SECURITY
631f9c18 2893 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 2894#endif
2895#ifdef CONFIG_KALLSYMS
edfcd606 2896 ONE("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 2897#endif
2ec220e2 2898#ifdef CONFIG_STACKTRACE
35a35046 2899 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671 2900#endif
5968cece 2901#ifdef CONFIG_SCHED_INFO
f6e826ca 2902 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 2903#endif
9745512c 2904#ifdef CONFIG_LATENCYTOP
631f9c18 2905 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 2906#endif
8793d854 2907#ifdef CONFIG_PROC_PID_CPUSET
52de4779 2908 ONE("cpuset", S_IRUGO, proc_cpuset_show),
a424316c
PM		 2909#endif
2910#ifdef CONFIG_CGROUPS
006f4ac4 2911 ONE("cgroup", S_IRUGO, proc_cgroup_show),
28a6d671 2912#endif
6ba51e37 2913 ONE("oom_score", S_IRUGO, proc_oom_score),
fa0cbbf1 2914 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
a63d83f4 2915 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 2916#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 2917 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2918 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 2919#endif
f4f154fd 2920#ifdef CONFIG_FAULT_INJECTION
631f9c18 2921 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 2922#endif
698ba7b5 2923#ifdef CONFIG_ELF_CORE
631f9c18 2924 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 2925#endif
aba76fdb 2926#ifdef CONFIG_TASK_IO_ACCOUNTING
19aadc98 2927 ONE("io", S_IRUSR, proc_tgid_io_accounting),
aba76fdb 2928#endif
f133ecca 2929#ifdef CONFIG_HARDWALL
d962c144 2930 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
f133ecca 2931#endif
22d917d8
EB		 2932#ifdef CONFIG_USER_NS
2933 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
2934 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
f76d207a 2935 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
9cc46516 2936 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
22d917d8 2937#endif
48f6a7a5
PE		 2938#ifdef CONFIG_CHECKPOINT_RESTORE
2939 REG("timers", S_IRUGO, proc_timers_operations),
2940#endif
5de23d43 2941 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
28a6d671 2942};
1da177e4 2943
f0c3b509 2944static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
1da177e4 2945{
f0c3b509
AV		 2946 return proc_pident_readdir(file, ctx,
2947 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2948}
2949
00977a59 2950static const struct file_operations proc_tgid_base_operations = {
1da177e4 2951 .read = generic_read_dir,
f50752ea
AV		 2952 .iterate_shared = proc_tgid_base_readdir,
2953 .llseek = generic_file_llseek,
1da177e4
LT		 2954};
2955
00cd8dd3
AV		 2956static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
2957{
7bcd6b0e
EB		 2958 return proc_pident_lookup(dir, dentry,
2959 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2960}
2961
c5ef1c42 2962static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 2963 .lookup = proc_tgid_base_lookup,
99f89551 2964 .getattr = pid_getattr,
6d76fa58 2965 .setattr = proc_setattr,
0499680a 2966 .permission = proc_pid_permission,
1da177e4 2967};
1da177e4 2968
60347f67 2969static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 2970{
48e6484d 2971 struct dentry *dentry, *leader, *dir;
8578cea7 2972 char buf[PROC_NUMBUF];
48e6484d
EB		 2973 struct qstr name;
2974
2975 name.name = buf;
60347f67 2976 name.len = snprintf(buf, sizeof(buf), "%d", pid);
4f522a24 2977 /* no ->d_hash() rejects on procfs */
60347f67 2978 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 2979 if (dentry) {
bbd51924 2980 d_invalidate(dentry);
48e6484d
EB		 2981 dput(dentry);
2982 }
1da177e4 2983
c35a7f18
ON		 2984 if (pid == tgid)
2985 return;
2986
48e6484d 2987 name.name = buf;
60347f67
PE		 2988 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2989 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 2990 if (!leader)
2991 goto out;
1da177e4 2992
48e6484d
EB		 2993 name.name = "task";
2994 name.len = strlen(name.name);
2995 dir = d_hash_and_lookup(leader, &name);
2996 if (!dir)
2997 goto out_put_leader;
2998
2999 name.name = buf;
60347f67 3000 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 3001 dentry = d_hash_and_lookup(dir, &name);
3002 if (dentry) {
bbd51924 3003 d_invalidate(dentry);
48e6484d 3004 dput(dentry);
1da177e4 3005 }
48e6484d
EB		 3006
3007 dput(dir);
3008out_put_leader:
3009 dput(leader);
3010out:
3011 return;
1da177e4
LT		 3012}
3013
0895e91d
RD		 3014/**
3015 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3016 * @task: task that should be flushed.
3017 *
3018 * When flushing dentries from proc, one needs to flush them from global
60347f67 3019 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 3020 * in. This call is supposed to do all of this job.
3021 *
3022 * Looks in the dcache for
3023 * /proc/@pid
3024 * /proc/@tgid/task/@pid
3025 * if either directory is present flushes it and all of it'ts children
3026 * from the dcache.
3027 *
3028 * It is safe and reasonable to cache /proc entries for a task until
3029 * that task exits. After that they just clog up the dcache with
3030 * useless entries, possibly causing useful dcache entries to be
3031 * flushed instead. This routine is proved to flush those useless
3032 * dcache entries at process exit time.
3033 *
3034 * NOTE: This routine is just an optimization so it does not guarantee
3035 * that no dcache entries will exist at process exit time it
3036 * just makes it very unlikely that any will persist.
60347f67
PE		 3037 */
3038
3039void proc_flush_task(struct task_struct *task)
3040{
9fcc2d15 3041 int i;
9b4d1cbe 3042 struct pid *pid, *tgid;
130f77ec
PE		 3043 struct upid *upid;
3044
130f77ec 3045 pid = task_pid(task);
9b4d1cbe 3046 tgid = task_tgid(task);
130f77ec 3047
9fcc2d15 3048 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 3049 upid = &pid->numbers[i];
3050 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 3051 tgid->numbers[i].nr);
130f77ec 3052 }
60347f67
PE		 3053}
3054
c52a47ac
AV		 3055static int proc_pid_instantiate(struct inode *dir,
3056 struct dentry * dentry,
3057 struct task_struct *task, const void *ptr)
444ceed8 3058{
444ceed8
EB		 3059 struct inode *inode;
3060
61a28784 3061 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3062 if (!inode)
3063 goto out;
3064
3065 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3066 inode->i_op = &proc_tgid_base_inode_operations;
3067 inode->i_fop = &proc_tgid_base_operations;
3068 inode->i_flags|=S_IMMUTABLE;
aed54175 3069
bfe86848
MS		 3070 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff,
3071 ARRAY_SIZE(tgid_base_stuff)));
444ceed8 3072
fb045adb 3073 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3074
3075 d_add(dentry, inode);
3076 /* Close the race of the process dying before we return the dentry */
0b728e19 3077 if (pid_revalidate(dentry, 0))
c52a47ac 3078 return 0;
444ceed8 3079out:
c52a47ac 3080 return -ENOENT;
444ceed8
EB		 3081}
3082
00cd8dd3 3083struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
1da177e4 3084{
335eb531 3085 int result = -ENOENT;
1da177e4 3086 struct task_struct *task;
1da177e4 3087 unsigned tgid;
b488893a 3088 struct pid_namespace *ns;
1da177e4 3089
dbcdb504 3090 tgid = name_to_int(&dentry->d_name);
1da177e4
LT		 3091 if (tgid == ~0U)
3092 goto out;
3093
b488893a 3094 ns = dentry->d_sb->s_fs_info;
de758734 3095 rcu_read_lock();
b488893a 3096 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 3097 if (task)
3098 get_task_struct(task);
de758734 3099 rcu_read_unlock();
1da177e4
LT		 3100 if (!task)
3101 goto out;
3102
444ceed8 3103 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 3104 put_task_struct(task);
1da177e4 3105out:
c52a47ac 3106 return ERR_PTR(result);
1da177e4
LT		 3107}
3108
1da177e4 3109/*
0804ef4b 3110 * Find the first task with tgid >= tgid
0bc58a91 3111 *
1da177e4 3112 */
19fd4bb2
EB		 3113struct tgid_iter {
3114 unsigned int tgid;
0804ef4b 3115 struct task_struct *task;
19fd4bb2
EB		 3116};
3117static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3118{
0804ef4b 3119 struct pid *pid;
1da177e4 3120
19fd4bb2
EB		 3121 if (iter.task)
3122 put_task_struct(iter.task);
454cc105 3123 rcu_read_lock();
0804ef4b 3124retry:
19fd4bb2
EB		 3125 iter.task = NULL;
3126 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 3127 if (pid) {
19fd4bb2
EB		 3128 iter.tgid = pid_nr_ns(pid, ns);
3129 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 3130 /* What we to know is if the pid we have find is the
3131 * pid of a thread_group_leader. Testing for task
3132 * being a thread_group_leader is the obvious thing
3133 * todo but there is a window when it fails, due to
3134 * the pid transfer logic in de_thread.
3135 *
3136 * So we perform the straight forward test of seeing
3137 * if the pid we have found is the pid of a thread
3138 * group leader, and don't worry if the task we have
3139 * found doesn't happen to be a thread group leader.
3140 * As we don't care in the case of readdir.
3141 */
19fd4bb2
EB		 3142 if (!iter.task || !has_group_leader_pid(iter.task)) {
3143 iter.tgid += 1;
0804ef4b 3144 goto retry;
19fd4bb2
EB		 3145 }
3146 get_task_struct(iter.task);
0bc58a91 3147 }
454cc105 3148 rcu_read_unlock();
19fd4bb2 3149 return iter;
1da177e4
LT		 3150}
3151
0097875b 3152#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
0804ef4b 3153
1da177e4 3154/* for the /proc/ directory itself, after non-process stuff has been done */
f0c3b509 3155int proc_pid_readdir(struct file *file, struct dir_context *ctx)
1da177e4 3156{
19fd4bb2 3157 struct tgid_iter iter;
3aa3377f 3158 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info;
f0c3b509 3159 loff_t pos = ctx->pos;
1da177e4 3160
021ada7d 3161 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
f0c3b509 3162 return 0;
1da177e4 3163
0097875b 3164 if (pos == TGID_OFFSET - 2) {
2b0143b5 3165 struct inode *inode = d_inode(ns->proc_self);
db963164 3166 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
f0c3b509 3167 return 0;
0097875b
EB		 3168 ctx->pos = pos = pos + 1;
3169 }
3170 if (pos == TGID_OFFSET - 1) {
2b0143b5 3171 struct inode *inode = d_inode(ns->proc_thread_self);
0097875b
EB		 3172 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3173 return 0;
3174 ctx->pos = pos = pos + 1;
021ada7d 3175 }
0097875b 3176 iter.tgid = pos - TGID_OFFSET;
19fd4bb2 3177 iter.task = NULL;
19fd4bb2
EB		 3178 for (iter = next_tgid(ns, iter);
3179 iter.task;
3180 iter.tgid += 1, iter = next_tgid(ns, iter)) {
f0c3b509
AV		 3181 char name[PROC_NUMBUF];
3182 int len;
3183 if (!has_pid_permissions(ns, iter.task, 2))
3184 continue;
0499680a 3185
f0c3b509
AV		 3186 len = snprintf(name, sizeof(name), "%d", iter.tgid);
3187 ctx->pos = iter.tgid + TGID_OFFSET;
3188 if (!proc_fill_cache(file, ctx, name, len,
3189 proc_pid_instantiate, iter.task, NULL)) {
19fd4bb2 3190 put_task_struct(iter.task);
f0c3b509 3191 return 0;
1da177e4 3192 }
0bc58a91 3193 }
f0c3b509 3194 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
0bc58a91
EB		 3195 return 0;
3196}
1da177e4 3197
1b3044e3
JD		 3198/*
3199 * proc_tid_comm_permission is a special permission function exclusively
3200 * used for the node /proc/<pid>/task/<tid>/comm.
3201 * It bypasses generic permission checks in the case where a task of the same
3202 * task group attempts to access the node.
3203 * The rationale behind this is that glibc and bionic access this node for
3204 * cross thread naming (pthread_set/getname_np(!self)). However, if
3205 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3206 * which locks out the cross thread naming implementation.
3207 * This function makes sure that the node is always accessible for members of
3208 * same thread group.
3209 */
3210static int proc_tid_comm_permission(struct inode *inode, int mask)
3211{
3212 bool is_same_tgroup;
3213 struct task_struct *task;
3214
3215 task = get_proc_task(inode);
3216 if (!task)
3217 return -ESRCH;
3218 is_same_tgroup = same_thread_group(current, task);
3219 put_task_struct(task);
3220
3221 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3222 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3223 * read or written by the members of the corresponding
3224 * thread group.
3225 */
3226 return 0;
3227 }
3228
3229 return generic_permission(inode, mask);
3230}
3231
3232static const struct inode_operations proc_tid_comm_inode_operations = {
3233 .permission = proc_tid_comm_permission,
3234};
3235
28a6d671
EB		 3236/*
3237 * Tasks
3238 */
c5141e6d 3239static const struct pid_entry tid_base_stuff[] = {
631f9c18 3240 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3241 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 3242 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
6ba8ed79
EB		 3243#ifdef CONFIG_NET
3244 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3245#endif
631f9c18 3246 REG("environ", S_IRUSR, proc_environ_operations),
c5317167 3247 REG("auxv", S_IRUSR, proc_auxv_operations),
631f9c18 3248 ONE("status", S_IRUGO, proc_pid_status),
35a35046 3249 ONE("personality", S_IRUSR, proc_pid_personality),
1c963eb1 3250 ONE("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3251#ifdef CONFIG_SCHED_DEBUG
631f9c18 3252 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3253#endif
1b3044e3
JD		 3254 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3255 &proc_tid_comm_inode_operations,
3256 &proc_pid_set_comm_operations, {}),
ebcb6734 3257#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
09d93bd6 3258 ONE("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 3259#endif
c2c0bb44 3260 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
631f9c18
AD		 3261 ONE("stat", S_IRUGO, proc_tid_stat),
3262 ONE("statm", S_IRUGO, proc_pid_statm),
b7643757 3263 REG("maps", S_IRUGO, proc_tid_maps_operations),
2e13ba54 3264#ifdef CONFIG_PROC_CHILDREN
81841161
CG		 3265 REG("children", S_IRUGO, proc_tid_children_operations),
3266#endif
28a6d671 3267#ifdef CONFIG_NUMA
b7643757 3268 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
28a6d671 3269#endif
631f9c18
AD		 3270 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3271 LNK("cwd", proc_cwd_link),
3272 LNK("root", proc_root_link),
3273 LNK("exe", proc_exe_link),
3274 REG("mounts", S_IRUGO, proc_mounts_operations),
3275 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3276#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18 3277 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
b7643757 3278 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
32ed74a4 3279 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 3280#endif
3281#ifdef CONFIG_SECURITY
631f9c18 3282 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3283#endif
3284#ifdef CONFIG_KALLSYMS
edfcd606 3285 ONE("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3286#endif
2ec220e2 3287#ifdef CONFIG_STACKTRACE
35a35046 3288 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671 3289#endif
5968cece 3290#ifdef CONFIG_SCHED_INFO
f6e826ca 3291 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3292#endif
9745512c 3293#ifdef CONFIG_LATENCYTOP
631f9c18 3294 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3295#endif
8793d854 3296#ifdef CONFIG_PROC_PID_CPUSET
52de4779 3297 ONE("cpuset", S_IRUGO, proc_cpuset_show),
a424316c
PM		 3298#endif
3299#ifdef CONFIG_CGROUPS
006f4ac4 3300 ONE("cgroup", S_IRUGO, proc_cgroup_show),
28a6d671 3301#endif
6ba51e37 3302 ONE("oom_score", S_IRUGO, proc_oom_score),
fa0cbbf1 3303 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
a63d83f4 3304 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3305#ifdef CONFIG_AUDITSYSCALL
631f9c18 3306 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
26ec3c64 3307 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3308#endif
f4f154fd 3309#ifdef CONFIG_FAULT_INJECTION
631f9c18 3310 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3311#endif
297c5d92 3312#ifdef CONFIG_TASK_IO_ACCOUNTING
19aadc98 3313 ONE("io", S_IRUSR, proc_tid_io_accounting),
297c5d92 3314#endif
f133ecca 3315#ifdef CONFIG_HARDWALL
d962c144 3316 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
f133ecca 3317#endif
22d917d8
EB		 3318#ifdef CONFIG_USER_NS
3319 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3320 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
f76d207a 3321 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
9cc46516 3322 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
22d917d8 3323#endif
28a6d671
EB		 3324};
3325
f0c3b509 3326static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
28a6d671 3327{
f0c3b509
AV		 3328 return proc_pident_readdir(file, ctx,
3329 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3330}
3331
00cd8dd3
AV		 3332static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3333{
7bcd6b0e
EB		 3334 return proc_pident_lookup(dir, dentry,
3335 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3336}
3337
00977a59 3338static const struct file_operations proc_tid_base_operations = {
28a6d671 3339 .read = generic_read_dir,
f50752ea
AV		 3340 .iterate_shared = proc_tid_base_readdir,
3341 .llseek = generic_file_llseek,
28a6d671
EB		 3342};
3343
c5ef1c42 3344static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3345 .lookup = proc_tid_base_lookup,
3346 .getattr = pid_getattr,
3347 .setattr = proc_setattr,
3348};
3349
c52a47ac 3350static int proc_task_instantiate(struct inode *dir,
c5141e6d 3351 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 3352{
444ceed8 3353 struct inode *inode;
61a28784 3354 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3355
3356 if (!inode)
3357 goto out;
3358 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3359 inode->i_op = &proc_tid_base_inode_operations;
3360 inode->i_fop = &proc_tid_base_operations;
3361 inode->i_flags|=S_IMMUTABLE;
aed54175 3362
bfe86848
MS		 3363 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff,
3364 ARRAY_SIZE(tid_base_stuff)));
444ceed8 3365
fb045adb 3366 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3367
3368 d_add(dentry, inode);
3369 /* Close the race of the process dying before we return the dentry */
0b728e19 3370 if (pid_revalidate(dentry, 0))
c52a47ac 3371 return 0;
444ceed8 3372out:
c52a47ac 3373 return -ENOENT;
444ceed8
EB		 3374}
3375
00cd8dd3 3376static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
28a6d671 3377{
c52a47ac 3378 int result = -ENOENT;
28a6d671
EB		 3379 struct task_struct *task;
3380 struct task_struct *leader = get_proc_task(dir);
28a6d671 3381 unsigned tid;
b488893a 3382 struct pid_namespace *ns;
28a6d671
EB		 3383
3384 if (!leader)
3385 goto out_no_task;
3386
dbcdb504 3387 tid = name_to_int(&dentry->d_name);
28a6d671
EB		 3388 if (tid == ~0U)
3389 goto out;
3390
b488893a 3391 ns = dentry->d_sb->s_fs_info;
28a6d671 3392 rcu_read_lock();
b488893a 3393 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3394 if (task)
3395 get_task_struct(task);
3396 rcu_read_unlock();
3397 if (!task)
3398 goto out;
bac0abd6 3399 if (!same_thread_group(leader, task))
28a6d671
EB		 3400 goto out_drop_task;
3401
444ceed8 3402 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3403out_drop_task:
3404 put_task_struct(task);
3405out:
3406 put_task_struct(leader);
3407out_no_task:
c52a47ac 3408 return ERR_PTR(result);
28a6d671
EB		 3409}
3410
0bc58a91
EB		 3411/*
3412 * Find the first tid of a thread group to return to user space.
3413 *
3414 * Usually this is just the thread group leader, but if the users
3415 * buffer was too small or there was a seek into the middle of the
3416 * directory we have more work todo.
3417 *
3418 * In the case of a short read we start with find_task_by_pid.
3419 *
3420 * In the case of a seek we start with the leader and walk nr
3421 * threads past it.
3422 */
9f6e963f
ON		 3423static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3424 struct pid_namespace *ns)
0bc58a91 3425{
d855a4b7 3426 struct task_struct *pos, *task;
9f6e963f
ON		 3427 unsigned long nr = f_pos;
3428
3429 if (nr != f_pos) /* 32bit overflow? */
3430 return NULL;
1da177e4 3431
cc288738 3432 rcu_read_lock();
d855a4b7
ON		 3433 task = pid_task(pid, PIDTYPE_PID);
3434 if (!task)
3435 goto fail;
3436
3437 /* Attempt to start with the tid of a thread */
9f6e963f 3438 if (tid && nr) {
b488893a 3439 pos = find_task_by_pid_ns(tid, ns);
d855a4b7 3440 if (pos && same_thread_group(pos, task))
a872ff0c 3441 goto found;
0bc58a91 3442 }
1da177e4 3443
0bc58a91 3444 /* If nr exceeds the number of threads there is nothing todo */
9f6e963f 3445 if (nr >= get_nr_threads(task))
c986c14a 3446 goto fail;
1da177e4 3447
a872ff0c
ON		 3448 /* If we haven't found our starting place yet start
3449 * with the leader and walk nr threads forward.
0bc58a91 3450 */
d855a4b7 3451 pos = task = task->group_leader;
c986c14a 3452 do {
9f6e963f 3453 if (!nr--)
c986c14a 3454 goto found;
d855a4b7 3455 } while_each_thread(task, pos);
c986c14a
ON		 3456fail:
3457 pos = NULL;
3458 goto out;
a872ff0c
ON		 3459found:
3460 get_task_struct(pos);
3461out:
cc288738 3462 rcu_read_unlock();
0bc58a91
EB		 3463 return pos;
3464}
3465
3466/*
3467 * Find the next thread in the thread list.
3468 * Return NULL if there is an error or no next thread.
3469 *
3470 * The reference to the input task_struct is released.
3471 */
3472static struct task_struct *next_tid(struct task_struct *start)
3473{
c1df7fb8 3474 struct task_struct *pos = NULL;
cc288738 3475 rcu_read_lock();
c1df7fb8 3476 if (pid_alive(start)) {
0bc58a91 3477 pos = next_thread(start);
c1df7fb8
ON		 3478 if (thread_group_leader(pos))
3479 pos = NULL;
3480 else
3481 get_task_struct(pos);
3482 }
cc288738 3483 rcu_read_unlock();
0bc58a91
EB		 3484 put_task_struct(start);
3485 return pos;
1da177e4
LT		 3486}
3487
3488/* for the /proc/TGID/task/ directories */
f0c3b509 3489static int proc_task_readdir(struct file *file, struct dir_context *ctx)
1da177e4 3490{
d855a4b7
ON		 3491 struct inode *inode = file_inode(file);
3492 struct task_struct *task;
b488893a 3493 struct pid_namespace *ns;
f0c3b509 3494 int tid;
1da177e4 3495
d855a4b7 3496 if (proc_inode_is_dead(inode))
f0c3b509 3497 return -ENOENT;
1da177e4 3498
f0c3b509 3499 if (!dir_emit_dots(file, ctx))
d855a4b7 3500 return 0;
1da177e4 3501
0bc58a91
EB		 3502 /* f_version caches the tgid value that the last readdir call couldn't
3503 * return. lseek aka telldir automagically resets f_version to 0.
3504 */
3aa3377f 3505 ns = inode->i_sb->s_fs_info;
f0c3b509
AV		 3506 tid = (int)file->f_version;
3507 file->f_version = 0;
d855a4b7 3508 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
0bc58a91 3509 task;
f0c3b509
AV		 3510 task = next_tid(task), ctx->pos++) {
3511 char name[PROC_NUMBUF];
3512 int len;
b488893a 3513 tid = task_pid_nr_ns(task, ns);
f0c3b509
AV		 3514 len = snprintf(name, sizeof(name), "%d", tid);
3515 if (!proc_fill_cache(file, ctx, name, len,
3516 proc_task_instantiate, task, NULL)) {
0bc58a91
EB		 3517 /* returning this tgid failed, save it as the first
3518 * pid for the next readir call */
f0c3b509 3519 file->f_version = (u64)tid;
0bc58a91 3520 put_task_struct(task);
1da177e4 3521 break;
0bc58a91 3522 }
1da177e4 3523 }
d855a4b7 3524
f0c3b509 3525 return 0;
1da177e4 3526}
6e66b52b
EB		 3527
3528static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3529{
2b0143b5 3530 struct inode *inode = d_inode(dentry);
99f89551 3531 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3532 generic_fillattr(inode, stat);
3533
99f89551 3534 if (p) {
99f89551 3535 stat->nlink += get_nr_threads(p);
99f89551 3536 put_task_struct(p);
6e66b52b
EB		 3537 }
3538
3539 return 0;
3540}
28a6d671 3541
c5ef1c42 3542static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3543 .lookup = proc_task_lookup,
3544 .getattr = proc_task_getattr,
3545 .setattr = proc_setattr,
0499680a 3546 .permission = proc_pid_permission,
28a6d671
EB		 3547};
3548
00977a59 3549static const struct file_operations proc_task_operations = {
28a6d671 3550 .read = generic_read_dir,
f50752ea
AV		 3551 .iterate_shared = proc_task_readdir,
3552 .llseek = generic_file_llseek,
28a6d671 3553};
Mirror https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git