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UBUNTU: SAUCE: Import aufs driver
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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
7c0f6ba6 50#include <linux/uaccess.h>
1da177e4 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
1270dd8d
AD		 107static u8 nlink_tid;
108static u8 nlink_tgid;
109
1da177e4 110struct pid_entry {
cedbccab 111 const char *name;
623f594e 112 unsigned int len;
d161a13f 113 umode_t mode;
c5ef1c42 114 const struct inode_operations *iop;
00977a59 115 const struct file_operations *fop;
20cdc894 116 union proc_op op;
1da177e4
LT		 117};
118
61a28784 119#define NOD(NAME, MODE, IOP, FOP, OP) { \
20cdc894 120 .name = (NAME), \
c5141e6d 121 .len = sizeof(NAME) - 1, \
20cdc894
EB		 122 .mode = MODE, \
123 .iop = IOP, \
124 .fop = FOP, \
125 .op = OP, \
126}
127
631f9c18
AD		 128#define DIR(NAME, MODE, iops, fops) \
129 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
130#define LNK(NAME, get_link) \
61a28784 131 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
20cdc894 132 &proc_pid_link_inode_operations, NULL, \
631f9c18
AD		 133 { .proc_get_link = get_link } )
134#define REG(NAME, MODE, fops) \
135 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
631f9c18 136#define ONE(NAME, MODE, show) \
be614086
EB		 137 NOD(NAME, (S_IFREG|(MODE)), \
138 NULL, &proc_single_file_operations, \
631f9c18 139 { .proc_show = show } )
1da177e4 140
aed54175
VN		 141/*
142 * Count the number of hardlinks for the pid_entry table, excluding the .
143 * and .. links.
144 */
1270dd8d 145static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,
aed54175
VN		 146 unsigned int n)
147{
148 unsigned int i;
149 unsigned int count;
150
1270dd8d 151 count = 2;
aed54175
VN		 152 for (i = 0; i < n; ++i) {
153 if (S_ISDIR(entries[i].mode))
154 ++count;
155 }
156
157 return count;
158}
159
f7ad3c6b 160static int get_task_root(struct task_struct *task, struct path *root)
1da177e4 161{
7c2c7d99
HD		 162 int result = -ENOENT;
163
0494f6ec 164 task_lock(task);
f7ad3c6b
MS		 165 if (task->fs) {
166 get_fs_root(task->fs, root);
7c2c7d99
HD		 167 result = 0;
168 }
0494f6ec 169 task_unlock(task);
7c2c7d99 170 return result;
0494f6ec
MS		 171}
172
7773fbc5 173static int proc_cwd_link(struct dentry *dentry, struct path *path)
0494f6ec 174{
2b0143b5 175 struct task_struct *task = get_proc_task(d_inode(dentry));
0494f6ec 176 int result = -ENOENT;
99f89551
EB		 177
178 if (task) {
f7ad3c6b
MS		 179 task_lock(task);
180 if (task->fs) {
181 get_fs_pwd(task->fs, path);
182 result = 0;
183 }
184 task_unlock(task);
99f89551
EB		 185 put_task_struct(task);
186 }
1da177e4
LT		 187 return result;
188}
189
7773fbc5 190static int proc_root_link(struct dentry *dentry, struct path *path)
1da177e4 191{
2b0143b5 192 struct task_struct *task = get_proc_task(d_inode(dentry));
1da177e4 193 int result = -ENOENT;
99f89551
EB		 194
195 if (task) {
f7ad3c6b 196 result = get_task_root(task, path);
99f89551
EB		 197 put_task_struct(task);
198 }
1da177e4
LT		 199 return result;
200}
201
c2c0bb44
AD		 202static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
203 size_t _count, loff_t *pos)
1da177e4 204{
c2c0bb44
AD		 205 struct task_struct *tsk;
206 struct mm_struct *mm;
207 char *page;
208 unsigned long count = _count;
209 unsigned long arg_start, arg_end, env_start, env_end;
210 unsigned long len1, len2, len;
211 unsigned long p;
212 char c;
213 ssize_t rv;
214
215 BUG_ON(*pos < 0);
216
217 tsk = get_proc_task(file_inode(file));
218 if (!tsk)
219 return -ESRCH;
220 mm = get_task_mm(tsk);
221 put_task_struct(tsk);
222 if (!mm)
223 return 0;
224 /* Check if process spawned far enough to have cmdline. */
225 if (!mm->env_end) {
226 rv = 0;
227 goto out_mmput;
228 }
229
230 page = (char *)__get_free_page(GFP_TEMPORARY);
231 if (!page) {
232 rv = -ENOMEM;
233 goto out_mmput;
234 }
235
236 down_read(&mm->mmap_sem);
237 arg_start = mm->arg_start;
238 arg_end = mm->arg_end;
239 env_start = mm->env_start;
240 env_end = mm->env_end;
241 up_read(&mm->mmap_sem);
242
243 BUG_ON(arg_start > arg_end);
244 BUG_ON(env_start > env_end);
245
246 len1 = arg_end - arg_start;
247 len2 = env_end - env_start;
248
3581d458
AD		 249 /* Empty ARGV. */
250 if (len1 == 0) {
251 rv = 0;
252 goto out_free_page;
253 }
2ca66ff7 254 /*
c2c0bb44
AD		 255 * Inherently racy -- command line shares address space
256 * with code and data.
2ca66ff7 257 */
272ddc8b 258 rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0);
c2c0bb44
AD		 259 if (rv <= 0)
260 goto out_free_page;
261
262 rv = 0;
263
264 if (c == '\0') {
265 /* Command line (set of strings) occupies whole ARGV. */
266 if (len1 <= *pos)
267 goto out_free_page;
268
269 p = arg_start + *pos;
270 len = len1 - *pos;
271 while (count > 0 && len > 0) {
272 unsigned int _count;
273 int nr_read;
274
275 _count = min3(count, len, PAGE_SIZE);
272ddc8b 276 nr_read = access_remote_vm(mm, p, page, _count, 0);
c2c0bb44
AD		 277 if (nr_read < 0)
278 rv = nr_read;
279 if (nr_read <= 0)
280 goto out_free_page;
281
282 if (copy_to_user(buf, page, nr_read)) {
283 rv = -EFAULT;
284 goto out_free_page;
285 }
286
287 p += nr_read;
288 len -= nr_read;
289 buf += nr_read;
290 count -= nr_read;
291 rv += nr_read;
292 }
293 } else {
294 /*
295 * Command line (1 string) occupies ARGV and maybe
296 * extends into ENVP.
297 */
298 if (len1 + len2 <= *pos)
299 goto skip_argv_envp;
300 if (len1 <= *pos)
301 goto skip_argv;
302
303 p = arg_start + *pos;
304 len = len1 - *pos;
305 while (count > 0 && len > 0) {
306 unsigned int _count, l;
307 int nr_read;
308 bool final;
309
310 _count = min3(count, len, PAGE_SIZE);
272ddc8b 311 nr_read = access_remote_vm(mm, p, page, _count, 0);
c2c0bb44
AD		 312 if (nr_read < 0)
313 rv = nr_read;
314 if (nr_read <= 0)
315 goto out_free_page;
316
317 /*
318 * Command line can be shorter than whole ARGV
319 * even if last "marker" byte says it is not.
320 */
321 final = false;
322 l = strnlen(page, nr_read);
323 if (l < nr_read) {
324 nr_read = l;
325 final = true;
326 }
327
328 if (copy_to_user(buf, page, nr_read)) {
329 rv = -EFAULT;
330 goto out_free_page;
331 }
332
333 p += nr_read;
334 len -= nr_read;
335 buf += nr_read;
336 count -= nr_read;
337 rv += nr_read;
338
339 if (final)
340 goto out_free_page;
341 }
342skip_argv:
343 /*
344 * Command line (1 string) occupies ARGV and
345 * extends into ENVP.
346 */
347 if (len1 <= *pos) {
348 p = env_start + *pos - len1;
349 len = len1 + len2 - *pos;
350 } else {
351 p = env_start;
352 len = len2;
353 }
354 while (count > 0 && len > 0) {
355 unsigned int _count, l;
356 int nr_read;
357 bool final;
358
359 _count = min3(count, len, PAGE_SIZE);
272ddc8b 360 nr_read = access_remote_vm(mm, p, page, _count, 0);
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);
a6071d80 694 struct user_namespace *s_user_ns;
6d76fa58
LT		 695
696 if (attr->ia_valid & ATTR_MODE)
697 return -EPERM;
698
a6071d80
EB		 699 /* Don't let anyone mess with weird proc files */
700 s_user_ns = inode->i_sb->s_user_ns;
701 if (!kuid_has_mapping(s_user_ns, inode->i_uid) ||
702 !kgid_has_mapping(s_user_ns, inode->i_gid))
703 return -EPERM;
704
31051c85 705 error = setattr_prepare(dentry, attr);
1025774c
CH		 706 if (error)
707 return error;
708
1025774c
CH		 709 setattr_copy(inode, attr);
710 mark_inode_dirty(inode);
711 return 0;
6d76fa58
LT		 712}
713
0499680a
VK		 714/*
715 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
716 * or euid/egid (for hide_pid_min=2)?
717 */
718static bool has_pid_permissions(struct pid_namespace *pid,
719 struct task_struct *task,
720 int hide_pid_min)
721{
722 if (pid->hide_pid < hide_pid_min)
723 return true;
724 if (in_group_p(pid->pid_gid))
725 return true;
caaee623 726 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
0499680a
VK		 727}
728
729
730static int proc_pid_permission(struct inode *inode, int mask)
731{
732 struct pid_namespace *pid = inode->i_sb->s_fs_info;
733 struct task_struct *task;
734 bool has_perms;
735
736 task = get_proc_task(inode);
a2ef990a
XF		 737 if (!task)
738 return -ESRCH;
0499680a
VK		 739 has_perms = has_pid_permissions(pid, task, 1);
740 put_task_struct(task);
741
742 if (!has_perms) {
743 if (pid->hide_pid == 2) {
744 /*
745 * Let's make getdents(), stat(), and open()
746 * consistent with each other. If a process
747 * may not stat() a file, it shouldn't be seen
748 * in procfs at all.
749 */
750 return -ENOENT;
751 }
752
753 return -EPERM;
754 }
755 return generic_permission(inode, mask);
756}
757
758
759
c5ef1c42 760static const struct inode_operations proc_def_inode_operations = {
6d76fa58
LT		 761 .setattr = proc_setattr,
762};
763
be614086
EB		 764static int proc_single_show(struct seq_file *m, void *v)
765{
766 struct inode *inode = m->private;
767 struct pid_namespace *ns;
768 struct pid *pid;
769 struct task_struct *task;
770 int ret;
771
772 ns = inode->i_sb->s_fs_info;
773 pid = proc_pid(inode);
774 task = get_pid_task(pid, PIDTYPE_PID);
775 if (!task)
776 return -ESRCH;
777
778 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
779
780 put_task_struct(task);
781 return ret;
782}
783
784static int proc_single_open(struct inode *inode, struct file *filp)
785{
c6a34058 786 return single_open(filp, proc_single_show, inode);
be614086
EB		 787}
788
789static const struct file_operations proc_single_file_operations = {
790 .open = proc_single_open,
791 .read = seq_read,
792 .llseek = seq_lseek,
793 .release = single_release,
794};
795
5381e169
ON		 796
797struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
1da177e4 798{
5381e169
ON		 799 struct task_struct *task = get_proc_task(inode);
800 struct mm_struct *mm = ERR_PTR(-ESRCH);
e268337d 801
5381e169 802 if (task) {
caaee623 803 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
5381e169 804 put_task_struct(task);
e268337d 805
5381e169
ON		 806 if (!IS_ERR_OR_NULL(mm)) {
807 /* ensure this mm_struct can't be freed */
808 atomic_inc(&mm->mm_count);
809 /* but do not pin its memory */
810 mmput(mm);
811 }
812 }
813
814 return mm;
815}
816
817static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
818{
819 struct mm_struct *mm = proc_mem_open(inode, mode);
e268337d
LT		 820
821 if (IS_ERR(mm))
822 return PTR_ERR(mm);
823
e268337d 824 file->private_data = mm;
1da177e4
LT		 825 return 0;
826}
827
b409e578
CW		 828static int mem_open(struct inode *inode, struct file *file)
829{
bc452b4b
DH		 830 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
831
832 /* OK to pass negative loff_t, we can catch out-of-range */
833 file->f_mode |= FMODE_UNSIGNED_OFFSET;
834
835 return ret;
b409e578
CW		 836}
837
572d34b9
ON		 838static ssize_t mem_rw(struct file *file, char __user *buf,
839 size_t count, loff_t *ppos, int write)
1da177e4 840{
e268337d 841 struct mm_struct *mm = file->private_data;
572d34b9
ON		 842 unsigned long addr = *ppos;
843 ssize_t copied;
1da177e4 844 char *page;
272ddc8b 845 unsigned int flags;
1da177e4 846
e268337d
LT		 847 if (!mm)
848 return 0;
99f89551 849
30cd8903
KM		 850 page = (char *)__get_free_page(GFP_TEMPORARY);
851 if (!page)
e268337d 852 return -ENOMEM;
1da177e4 853
f7ca54f4 854 copied = 0;
6d08f2c7
ON		 855 if (!atomic_inc_not_zero(&mm->mm_users))
856 goto free;
857
272ddc8b
LT		 858 /* Maybe we should limit FOLL_FORCE to actual ptrace users? */
859 flags = FOLL_FORCE;
6347e8d5
LS		 860 if (write)
861 flags |= FOLL_WRITE;
862
1da177e4 863 while (count > 0) {
572d34b9 864 int this_len = min_t(int, count, PAGE_SIZE);
1da177e4 865
572d34b9 866 if (write && copy_from_user(page, buf, this_len)) {
1da177e4
LT		 867 copied = -EFAULT;
868 break;
869 }
572d34b9 870
6347e8d5 871 this_len = access_remote_vm(mm, addr, page, this_len, flags);
572d34b9 872 if (!this_len) {
1da177e4
LT		 873 if (!copied)
874 copied = -EIO;
875 break;
876 }
572d34b9
ON		 877
878 if (!write && copy_to_user(buf, page, this_len)) {
879 copied = -EFAULT;
880 break;
881 }
882
883 buf += this_len;
884 addr += this_len;
885 copied += this_len;
886 count -= this_len;
1da177e4 887 }
572d34b9 888 *ppos = addr;
30cd8903 889
6d08f2c7
ON		 890 mmput(mm);
891free:
30cd8903 892 free_page((unsigned long) page);
1da177e4
LT		 893 return copied;
894}
1da177e4 895
572d34b9
ON		 896static ssize_t mem_read(struct file *file, char __user *buf,
897 size_t count, loff_t *ppos)
898{
899 return mem_rw(file, buf, count, ppos, 0);
900}
901
902static ssize_t mem_write(struct file *file, const char __user *buf,
903 size_t count, loff_t *ppos)
904{
905 return mem_rw(file, (char __user*)buf, count, ppos, 1);
906}
907
85863e47 908loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 909{
910 switch (orig) {
911 case 0:
912 file->f_pos = offset;
913 break;
914 case 1:
915 file->f_pos += offset;
916 break;
917 default:
918 return -EINVAL;
919 }
920 force_successful_syscall_return();
921 return file->f_pos;
922}
923
e268337d
LT		 924static int mem_release(struct inode *inode, struct file *file)
925{
926 struct mm_struct *mm = file->private_data;
71879d3c 927 if (mm)
6d08f2c7 928 mmdrop(mm);
e268337d
LT		 929 return 0;
930}
931
00977a59 932static const struct file_operations proc_mem_operations = {
1da177e4
LT		 933 .llseek = mem_lseek,
934 .read = mem_read,
935 .write = mem_write,
936 .open = mem_open,
e268337d 937 .release = mem_release,
1da177e4
LT		 938};
939
b409e578
CW		 940static int environ_open(struct inode *inode, struct file *file)
941{
942 return __mem_open(inode, file, PTRACE_MODE_READ);
943}
944
315e28c8
JP		 945static ssize_t environ_read(struct file *file, char __user *buf,
946 size_t count, loff_t *ppos)
947{
315e28c8
JP		 948 char *page;
949 unsigned long src = *ppos;
b409e578
CW		 950 int ret = 0;
951 struct mm_struct *mm = file->private_data;
a3b609ef 952 unsigned long env_start, env_end;
315e28c8 953
8148a73c
MK		 954 /* Ensure the process spawned far enough to have an environment. */
955 if (!mm || !mm->env_end)
b409e578 956 return 0;
315e28c8 957
315e28c8
JP		 958 page = (char *)__get_free_page(GFP_TEMPORARY);
959 if (!page)
b409e578 960 return -ENOMEM;
315e28c8 961
d6f64b89 962 ret = 0;
b409e578
CW		 963 if (!atomic_inc_not_zero(&mm->mm_users))
964 goto free;
a3b609ef
MG		 965
966 down_read(&mm->mmap_sem);
967 env_start = mm->env_start;
968 env_end = mm->env_end;
969 up_read(&mm->mmap_sem);
970
315e28c8 971 while (count > 0) {
e8905ec2
DH		 972 size_t this_len, max_len;
973 int retval;
315e28c8 974
a3b609ef 975 if (src >= (env_end - env_start))
315e28c8
JP		 976 break;
977
a3b609ef 978 this_len = env_end - (env_start + src);
e8905ec2
DH		 979
980 max_len = min_t(size_t, PAGE_SIZE, count);
981 this_len = min(max_len, this_len);
315e28c8 982
272ddc8b 983 retval = access_remote_vm(mm, (env_start + src), page, this_len, 0);
315e28c8
JP		 984
985 if (retval <= 0) {
986 ret = retval;
987 break;
988 }
989
990 if (copy_to_user(buf, page, retval)) {
991 ret = -EFAULT;
992 break;
993 }
994
995 ret += retval;
996 src += retval;
997 buf += retval;
998 count -= retval;
999 }
1000 *ppos = src;
315e28c8 1001 mmput(mm);
b409e578
CW		 1002
1003free:
315e28c8 1004 free_page((unsigned long) page);
315e28c8
JP		 1005 return ret;
1006}
1007
1008static const struct file_operations proc_environ_operations = {
b409e578 1009 .open = environ_open,
315e28c8 1010 .read = environ_read,
87df8424 1011 .llseek = generic_file_llseek,
b409e578 1012 .release = mem_release,
315e28c8
JP		 1013};
1014
c5317167
AV		 1015static int auxv_open(struct inode *inode, struct file *file)
1016{
1017 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
1018}
1019
1020static ssize_t auxv_read(struct file *file, char __user *buf,
1021 size_t count, loff_t *ppos)
1022{
1023 struct mm_struct *mm = file->private_data;
1024 unsigned int nwords = 0;
06b2849d
LY		 1025
1026 if (!mm)
1027 return 0;
c5317167
AV		 1028 do {
1029 nwords += 2;
1030 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1031 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,
1032 nwords * sizeof(mm->saved_auxv[0]));
1033}
1034
1035static const struct file_operations proc_auxv_operations = {
1036 .open = auxv_open,
1037 .read = auxv_read,
1038 .llseek = generic_file_llseek,
1039 .release = mem_release,
1040};
1041
fa0cbbf1
DR		 1042static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1043 loff_t *ppos)
1044{
496ad9aa 1045 struct task_struct *task = get_proc_task(file_inode(file));
fa0cbbf1
DR		 1046 char buffer[PROC_NUMBUF];
1047 int oom_adj = OOM_ADJUST_MIN;
1048 size_t len;
fa0cbbf1
DR		 1049
1050 if (!task)
1051 return -ESRCH;
f913da59
MH		 1052 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1053 oom_adj = OOM_ADJUST_MAX;
1054 else
1055 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1056 OOM_SCORE_ADJ_MAX;
fa0cbbf1
DR		 1057 put_task_struct(task);
1058 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1059 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1060}
1061
1d5f0acb
MH		 1062static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
1063{
1064 static DEFINE_MUTEX(oom_adj_mutex);
44a70ade 1065 struct mm_struct *mm = NULL;
1d5f0acb
MH		 1066 struct task_struct *task;
1067 int err = 0;
1068
1069 task = get_proc_task(file_inode(file));
1070 if (!task)
1071 return -ESRCH;
1072
1073 mutex_lock(&oom_adj_mutex);
1074 if (legacy) {
1075 if (oom_adj < task->signal->oom_score_adj &&
1076 !capable(CAP_SYS_RESOURCE)) {
1077 err = -EACCES;
1078 goto err_unlock;
1079 }
1080 /*
1081 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1082 * /proc/pid/oom_score_adj instead.
1083 */
1084 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1085 current->comm, task_pid_nr(current), task_pid_nr(task),
1086 task_pid_nr(task));
1087 } else {
1088 if ((short)oom_adj < task->signal->oom_score_adj_min &&
1089 !capable(CAP_SYS_RESOURCE)) {
1090 err = -EACCES;
1091 goto err_unlock;
1092 }
1093 }
1094
44a70ade
MH		 1095 /*
1096 * Make sure we will check other processes sharing the mm if this is
1097 * not vfrok which wants its own oom_score_adj.
1098 * pin the mm so it doesn't go away and get reused after task_unlock
1099 */
1100 if (!task->vfork_done) {
1101 struct task_struct *p = find_lock_task_mm(task);
1102
1103 if (p) {
1104 if (atomic_read(&p->mm->mm_users) > 1) {
1105 mm = p->mm;
1106 atomic_inc(&mm->mm_count);
1107 }
1108 task_unlock(p);
1109 }
1110 }
1111
1d5f0acb
MH		 1112 task->signal->oom_score_adj = oom_adj;
1113 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1114 task->signal->oom_score_adj_min = (short)oom_adj;
1115 trace_oom_score_adj_update(task);
44a70ade
MH		 1116
1117 if (mm) {
1118 struct task_struct *p;
1119
1120 rcu_read_lock();
1121 for_each_process(p) {
1122 if (same_thread_group(task, p))
1123 continue;
1124
1125 /* do not touch kernel threads or the global init */
1126 if (p->flags & PF_KTHREAD || is_global_init(p))
1127 continue;
1128
1129 task_lock(p);
1130 if (!p->vfork_done && process_shares_mm(p, mm)) {
1131 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",
1132 task_pid_nr(p), p->comm,
1133 p->signal->oom_score_adj, oom_adj,
1134 task_pid_nr(task), task->comm);
1135 p->signal->oom_score_adj = oom_adj;
1136 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1137 p->signal->oom_score_adj_min = (short)oom_adj;
1138 }
1139 task_unlock(p);
1140 }
1141 rcu_read_unlock();
1142 mmdrop(mm);
1143 }
1d5f0acb
MH		 1144err_unlock:
1145 mutex_unlock(&oom_adj_mutex);
1146 put_task_struct(task);
1147 return err;
1148}
f913da59 1149
b72bdfa7
DR		 1150/*
1151 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1152 * kernels. The effective policy is defined by oom_score_adj, which has a
1153 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1154 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1155 * Processes that become oom disabled via oom_adj will still be oom disabled
1156 * with this implementation.
1157 *
1158 * oom_adj cannot be removed since existing userspace binaries use it.
1159 */
fa0cbbf1
DR		 1160static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1161 size_t count, loff_t *ppos)
1162{
fa0cbbf1
DR		 1163 char buffer[PROC_NUMBUF];
1164 int oom_adj;
fa0cbbf1
DR		 1165 int err;
1166
1167 memset(buffer, 0, sizeof(buffer));
1168 if (count > sizeof(buffer) - 1)
1169 count = sizeof(buffer) - 1;
1170 if (copy_from_user(buffer, buf, count)) {
1171 err = -EFAULT;
1172 goto out;
1173 }
1174
1175 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1176 if (err)
1177 goto out;
1178 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1179 oom_adj != OOM_DISABLE) {
1180 err = -EINVAL;
1181 goto out;
1182 }
1183
fa0cbbf1
DR		 1184 /*
1185 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1186 * value is always attainable.
1187 */
1188 if (oom_adj == OOM_ADJUST_MAX)
1189 oom_adj = OOM_SCORE_ADJ_MAX;
1190 else
1191 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1192
1d5f0acb 1193 err = __set_oom_adj(file, oom_adj, true);
fa0cbbf1
DR		 1194out:
1195 return err < 0 ? err : count;
1196}
1197
1198static const struct file_operations proc_oom_adj_operations = {
1199 .read = oom_adj_read,
1200 .write = oom_adj_write,
1201 .llseek = generic_file_llseek,
1202};
1203
a63d83f4
DR		 1204static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1205 size_t count, loff_t *ppos)
1206{
496ad9aa 1207 struct task_struct *task = get_proc_task(file_inode(file));
a63d83f4 1208 char buffer[PROC_NUMBUF];
a9c58b90 1209 short oom_score_adj = OOM_SCORE_ADJ_MIN;
a63d83f4
DR		 1210 size_t len;
1211
1212 if (!task)
1213 return -ESRCH;
f913da59 1214 oom_score_adj = task->signal->oom_score_adj;
a63d83f4 1215 put_task_struct(task);
a9c58b90 1216 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
a63d83f4
DR		 1217 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1218}
1219
1220static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1221 size_t count, loff_t *ppos)
1222{
a63d83f4 1223 char buffer[PROC_NUMBUF];
0a8cb8e3 1224 int oom_score_adj;
a63d83f4
DR		 1225 int err;
1226
1227 memset(buffer, 0, sizeof(buffer));
1228 if (count > sizeof(buffer) - 1)
1229 count = sizeof(buffer) - 1;
723548bf
DR		 1230 if (copy_from_user(buffer, buf, count)) {
1231 err = -EFAULT;
1232 goto out;
1233 }
a63d83f4 1234
0a8cb8e3 1235 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
a63d83f4 1236 if (err)
723548bf 1237 goto out;
a63d83f4 1238 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
723548bf
DR		 1239 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1240 err = -EINVAL;
1241 goto out;
1242 }
a63d83f4 1243
1d5f0acb 1244 err = __set_oom_adj(file, oom_score_adj, false);
723548bf
DR		 1245out:
1246 return err < 0 ? err : count;
a63d83f4
DR		 1247}
1248
1249static const struct file_operations proc_oom_score_adj_operations = {
1250 .read = oom_score_adj_read,
1251 .write = oom_score_adj_write,
6038f373 1252 .llseek = default_llseek,
a63d83f4
DR		 1253};
1254
1da177e4 1255#ifdef CONFIG_AUDITSYSCALL
b4eb4f7f 1256#define TMPBUFLEN 11
1da177e4
LT		 1257static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1258 size_t count, loff_t *ppos)
1259{
496ad9aa 1260 struct inode * inode = file_inode(file);
99f89551 1261 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1262 ssize_t length;
1263 char tmpbuf[TMPBUFLEN];
1264
99f89551
EB		 1265 if (!task)
1266 return -ESRCH;
1da177e4 1267 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
e1760bd5
EB		 1268 from_kuid(file->f_cred->user_ns,
1269 audit_get_loginuid(task)));
99f89551 1270 put_task_struct(task);
1da177e4
LT		 1271 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1272}
1273
1274static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1275 size_t count, loff_t *ppos)
1276{
496ad9aa 1277 struct inode * inode = file_inode(file);
1da177e4 1278 uid_t loginuid;
e1760bd5 1279 kuid_t kloginuid;
774636e1 1280 int rv;
1da177e4 1281
7dc52157
PM		 1282 rcu_read_lock();
1283 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1284 rcu_read_unlock();
1da177e4 1285 return -EPERM;
7dc52157
PM		 1286 }
1287 rcu_read_unlock();
1da177e4 1288
1da177e4
LT		 1289 if (*ppos != 0) {
1290 /* No partial writes. */
1291 return -EINVAL;
1292 }
1da177e4 1293
774636e1
AD		 1294 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1295 if (rv < 0)
1296 return rv;
81407c84
EP		 1297
1298 /* is userspace tring to explicitly UNSET the loginuid? */
1299 if (loginuid == AUDIT_UID_UNSET) {
1300 kloginuid = INVALID_UID;
1301 } else {
1302 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
774636e1
AD		 1303 if (!uid_valid(kloginuid))
1304 return -EINVAL;
e1760bd5
EB		 1305 }
1306
774636e1
AD		 1307 rv = audit_set_loginuid(kloginuid);
1308 if (rv < 0)
1309 return rv;
1310 return count;
1da177e4
LT		 1311}
1312
00977a59 1313static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1314 .read = proc_loginuid_read,
1315 .write = proc_loginuid_write,
87df8424 1316 .llseek = generic_file_llseek,
1da177e4 1317};
1e0bd755
EP		 1318
1319static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1320 size_t count, loff_t *ppos)
1321{
496ad9aa 1322 struct inode * inode = file_inode(file);
1e0bd755
EP		 1323 struct task_struct *task = get_proc_task(inode);
1324 ssize_t length;
1325 char tmpbuf[TMPBUFLEN];
1326
1327 if (!task)
1328 return -ESRCH;
1329 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1330 audit_get_sessionid(task));
1331 put_task_struct(task);
1332 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1333}
1334
1335static const struct file_operations proc_sessionid_operations = {
1336 .read = proc_sessionid_read,
87df8424 1337 .llseek = generic_file_llseek,
1e0bd755 1338};
1da177e4
LT		 1339#endif
1340
f4f154fd
AM		 1341#ifdef CONFIG_FAULT_INJECTION
1342static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1343 size_t count, loff_t *ppos)
1344{
496ad9aa 1345 struct task_struct *task = get_proc_task(file_inode(file));
f4f154fd
AM		 1346 char buffer[PROC_NUMBUF];
1347 size_t len;
1348 int make_it_fail;
f4f154fd
AM		 1349
1350 if (!task)
1351 return -ESRCH;
1352 make_it_fail = task->make_it_fail;
1353 put_task_struct(task);
1354
1355 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1356
1357 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1358}
1359
1360static ssize_t proc_fault_inject_write(struct file * file,
1361 const char __user * buf, size_t count, loff_t *ppos)
1362{
1363 struct task_struct *task;
774636e1 1364 char buffer[PROC_NUMBUF];
f4f154fd 1365 int make_it_fail;
774636e1 1366 int rv;
f4f154fd
AM		 1367
1368 if (!capable(CAP_SYS_RESOURCE))
1369 return -EPERM;
1370 memset(buffer, 0, sizeof(buffer));
1371 if (count > sizeof(buffer) - 1)
1372 count = sizeof(buffer) - 1;
1373 if (copy_from_user(buffer, buf, count))
1374 return -EFAULT;
774636e1
AD		 1375 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1376 if (rv < 0)
1377 return rv;
16caed31
DJ		 1378 if (make_it_fail < 0 || make_it_fail > 1)
1379 return -EINVAL;
1380
496ad9aa 1381 task = get_proc_task(file_inode(file));
f4f154fd
AM		 1382 if (!task)
1383 return -ESRCH;
1384 task->make_it_fail = make_it_fail;
1385 put_task_struct(task);
cba8aafe
VL		 1386
1387 return count;
f4f154fd
AM		 1388}
1389
00977a59 1390static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1391 .read = proc_fault_inject_read,
1392 .write = proc_fault_inject_write,
87df8424 1393 .llseek = generic_file_llseek,
f4f154fd
AM		 1394};
1395#endif
1396
9745512c 1397
43ae34cb
IM		 1398#ifdef CONFIG_SCHED_DEBUG
1399/*
1400 * Print out various scheduling related per-task fields:
1401 */
1402static int sched_show(struct seq_file *m, void *v)
1403{
1404 struct inode *inode = m->private;
1405 struct task_struct *p;
1406
43ae34cb
IM		 1407 p = get_proc_task(inode);
1408 if (!p)
1409 return -ESRCH;
1410 proc_sched_show_task(p, m);
1411
1412 put_task_struct(p);
1413
1414 return 0;
1415}
1416
1417static ssize_t
1418sched_write(struct file *file, const char __user *buf,
1419 size_t count, loff_t *offset)
1420{
496ad9aa 1421 struct inode *inode = file_inode(file);
43ae34cb
IM		 1422 struct task_struct *p;
1423
43ae34cb
IM		 1424 p = get_proc_task(inode);
1425 if (!p)
1426 return -ESRCH;
1427 proc_sched_set_task(p);
1428
1429 put_task_struct(p);
1430
1431 return count;
1432}
1433
1434static int sched_open(struct inode *inode, struct file *filp)
1435{
c6a34058 1436 return single_open(filp, sched_show, inode);
43ae34cb
IM		 1437}
1438
1439static const struct file_operations proc_pid_sched_operations = {
1440 .open = sched_open,
1441 .read = seq_read,
1442 .write = sched_write,
1443 .llseek = seq_lseek,
5ea473a1 1444 .release = single_release,
43ae34cb
IM		 1445};
1446
1447#endif
1448
5091faa4
MG		 1449#ifdef CONFIG_SCHED_AUTOGROUP
1450/*
1451 * Print out autogroup related information:
1452 */
1453static int sched_autogroup_show(struct seq_file *m, void *v)
1454{
1455 struct inode *inode = m->private;
1456 struct task_struct *p;
1457
1458 p = get_proc_task(inode);
1459 if (!p)
1460 return -ESRCH;
1461 proc_sched_autogroup_show_task(p, m);
1462
1463 put_task_struct(p);
1464
1465 return 0;
1466}
1467
1468static ssize_t
1469sched_autogroup_write(struct file *file, const char __user *buf,
1470 size_t count, loff_t *offset)
1471{
496ad9aa 1472 struct inode *inode = file_inode(file);
5091faa4
MG		 1473 struct task_struct *p;
1474 char buffer[PROC_NUMBUF];
0a8cb8e3 1475 int nice;
5091faa4
MG		 1476 int err;
1477
1478 memset(buffer, 0, sizeof(buffer));
1479 if (count > sizeof(buffer) - 1)
1480 count = sizeof(buffer) - 1;
1481 if (copy_from_user(buffer, buf, count))
1482 return -EFAULT;
1483
0a8cb8e3
AD		 1484 err = kstrtoint(strstrip(buffer), 0, &nice);
1485 if (err < 0)
1486 return err;
5091faa4
MG		 1487
1488 p = get_proc_task(inode);
1489 if (!p)
1490 return -ESRCH;
1491
2e5b5b3a 1492 err = proc_sched_autogroup_set_nice(p, nice);
5091faa4
MG		 1493 if (err)
1494 count = err;
1495
1496 put_task_struct(p);
1497
1498 return count;
1499}
1500
1501static int sched_autogroup_open(struct inode *inode, struct file *filp)
1502{
1503 int ret;
1504
1505 ret = single_open(filp, sched_autogroup_show, NULL);
1506 if (!ret) {
1507 struct seq_file *m = filp->private_data;
1508
1509 m->private = inode;
1510 }
1511 return ret;
1512}
1513
1514static const struct file_operations proc_pid_sched_autogroup_operations = {
1515 .open = sched_autogroup_open,
1516 .read = seq_read,
1517 .write = sched_autogroup_write,
1518 .llseek = seq_lseek,
1519 .release = single_release,
1520};
1521
1522#endif /* CONFIG_SCHED_AUTOGROUP */
1523
4614a696
JS		 1524static ssize_t comm_write(struct file *file, const char __user *buf,
1525 size_t count, loff_t *offset)
1526{
496ad9aa 1527 struct inode *inode = file_inode(file);
4614a696
JS		 1528 struct task_struct *p;
1529 char buffer[TASK_COMM_LEN];
830e0fc9 1530 const size_t maxlen = sizeof(buffer) - 1;
4614a696
JS		 1531
1532 memset(buffer, 0, sizeof(buffer));
830e0fc9 1533 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
4614a696
JS		 1534 return -EFAULT;
1535
1536 p = get_proc_task(inode);
1537 if (!p)
1538 return -ESRCH;
1539
1540 if (same_thread_group(current, p))
1541 set_task_comm(p, buffer);
1542 else
1543 count = -EINVAL;
1544
1545 put_task_struct(p);
1546
1547 return count;
1548}
1549
1550static int comm_show(struct seq_file *m, void *v)
1551{
1552 struct inode *inode = m->private;
1553 struct task_struct *p;
1554
1555 p = get_proc_task(inode);
1556 if (!p)
1557 return -ESRCH;
1558
1559 task_lock(p);
1560 seq_printf(m, "%s\n", p->comm);
1561 task_unlock(p);
1562
1563 put_task_struct(p);
1564
1565 return 0;
1566}
1567
1568static int comm_open(struct inode *inode, struct file *filp)
1569{
c6a34058 1570 return single_open(filp, comm_show, inode);
4614a696
JS		 1571}
1572
1573static const struct file_operations proc_pid_set_comm_operations = {
1574 .open = comm_open,
1575 .read = seq_read,
1576 .write = comm_write,
1577 .llseek = seq_lseek,
1578 .release = single_release,
1579};
1580
7773fbc5 1581static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
925d1c40
MH		 1582{
1583 struct task_struct *task;
925d1c40
MH		 1584 struct file *exe_file;
1585
2b0143b5 1586 task = get_proc_task(d_inode(dentry));
925d1c40
MH		 1587 if (!task)
1588 return -ENOENT;
cd81a917 1589 exe_file = get_task_exe_file(task);
925d1c40 1590 put_task_struct(task);
925d1c40
MH		 1591 if (exe_file) {
1592 *exe_path = exe_file->f_path;
1593 path_get(&exe_file->f_path);
1594 fput(exe_file);
1595 return 0;
1596 } else
1597 return -ENOENT;
1598}
1599
6b255391 1600static const char *proc_pid_get_link(struct dentry *dentry,
fceef393
AV		 1601 struct inode *inode,
1602 struct delayed_call *done)
1da177e4 1603{
408ef013 1604 struct path path;
1da177e4
LT		 1605 int error = -EACCES;
1606
6b255391
AV		 1607 if (!dentry)
1608 return ERR_PTR(-ECHILD);
1609
778c1144
EB		 1610 /* Are we allowed to snoop on the tasks file descriptors? */
1611 if (!proc_fd_access_allowed(inode))
1da177e4 1612 goto out;
1da177e4 1613
408ef013
CH		 1614 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1615 if (error)
1616 goto out;
1617
6e77137b 1618 nd_jump_link(&path);
408ef013 1619 return NULL;
1da177e4 1620out:
008b150a 1621 return ERR_PTR(error);
1da177e4
LT		 1622}
1623
3dcd25f3 1624static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1625{
e12ba74d 1626 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1627 char *pathname;
1da177e4
LT		 1628 int len;
1629
1630 if (!tmp)
1631 return -ENOMEM;
0c28f287 1632
7b2a69ba 1633 pathname = d_path(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1634 len = PTR_ERR(pathname);
1635 if (IS_ERR(pathname))
1da177e4 1636 goto out;
3dcd25f3 1637 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1638
1639 if (len > buflen)
1640 len = buflen;
3dcd25f3 1641 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1642 len = -EFAULT;
1643 out:
1644 free_page((unsigned long)tmp);
1645 return len;
1646}
1647
1648static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1649{
1650 int error = -EACCES;
2b0143b5 1651 struct inode *inode = d_inode(dentry);
3dcd25f3 1652 struct path path;
1da177e4 1653
778c1144
EB		 1654 /* Are we allowed to snoop on the tasks file descriptors? */
1655 if (!proc_fd_access_allowed(inode))
1da177e4 1656 goto out;
1da177e4 1657
7773fbc5 1658 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1da177e4
LT		 1659 if (error)
1660 goto out;
1661
3dcd25f3
JB		 1662 error = do_proc_readlink(&path, buffer, buflen);
1663 path_put(&path);
1da177e4 1664out:
1da177e4
LT		 1665 return error;
1666}
1667
faf60af1 1668const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1669 .readlink = proc_pid_readlink,
6b255391 1670 .get_link = proc_pid_get_link,
6d76fa58 1671 .setattr = proc_setattr,
1da177e4
LT		 1672};
1673
28a6d671
EB		 1674
1675/* building an inode */
1676
db978da8
AG		 1677struct inode *proc_pid_make_inode(struct super_block * sb,
1678 struct task_struct *task, umode_t mode)
28a6d671
EB		 1679{
1680 struct inode * inode;
1681 struct proc_inode *ei;
c69e8d9c 1682 const struct cred *cred;
1da177e4 1683
28a6d671 1684 /* We need a new inode */
1da177e4 1685
28a6d671
EB		 1686 inode = new_inode(sb);
1687 if (!inode)
1688 goto out;
1689
1690 /* Common stuff */
1691 ei = PROC_I(inode);
db978da8 1692 inode->i_mode = mode;
85fe4025 1693 inode->i_ino = get_next_ino();
078cd827 1694 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
28a6d671
EB		 1695 inode->i_op = &proc_def_inode_operations;
1696
1697 /*
1698 * grab the reference to task.
1699 */
1a657f78 1700 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1701 if (!ei->pid)
1702 goto out_unlock;
1703
28a6d671 1704 if (task_dumpable(task)) {
c69e8d9c
DH		 1705 rcu_read_lock();
1706 cred = __task_cred(task);
1707 inode->i_uid = cred->euid;
1708 inode->i_gid = cred->egid;
1709 rcu_read_unlock();
1da177e4 1710 }
28a6d671
EB		 1711 security_task_to_inode(task, inode);
1712
1da177e4 1713out:
28a6d671
EB		 1714 return inode;
1715
1716out_unlock:
1717 iput(inode);
1718 return NULL;
1da177e4
LT		 1719}
1720
6b4e306a 1721int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1722{
2b0143b5 1723 struct inode *inode = d_inode(dentry);
28a6d671 1724 struct task_struct *task;
c69e8d9c 1725 const struct cred *cred;
0499680a 1726 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
c69e8d9c 1727
28a6d671 1728 generic_fillattr(inode, stat);
1da177e4 1729
28a6d671 1730 rcu_read_lock();
dcb0f222
EB		 1731 stat->uid = GLOBAL_ROOT_UID;
1732 stat->gid = GLOBAL_ROOT_GID;
28a6d671
EB		 1733 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1734 if (task) {
0499680a
VK		 1735 if (!has_pid_permissions(pid, task, 2)) {
1736 rcu_read_unlock();
1737 /*
1738 * This doesn't prevent learning whether PID exists,
1739 * it only makes getattr() consistent with readdir().
1740 */
1741 return -ENOENT;
1742 }
28a6d671
EB		 1743 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1744 task_dumpable(task)) {
c69e8d9c
DH		 1745 cred = __task_cred(task);
1746 stat->uid = cred->euid;
1747 stat->gid = cred->egid;
1da177e4
LT		 1748 }
1749 }
28a6d671 1750 rcu_read_unlock();
d6e71144 1751 return 0;
1da177e4
LT		 1752}
1753
1da177e4
LT		 1754/* dentry stuff */
1755
1756/*
1757 * Exceptional case: normally we are not allowed to unhash a busy
1758 * directory. In this case, however, we can do it - no aliasing problems
1759 * due to the way we treat inodes.
1760 *
1761 * Rewrite the inode's ownerships here because the owning task may have
1762 * performed a setuid(), etc.
99f89551
EB		 1763 *
1764 * Before the /proc/pid/status file was created the only way to read
1765 * the effective uid of a /process was to stat /proc/pid. Reading
1766 * /proc/pid/status is slow enough that procps and other packages
1767 * kept stating /proc/pid. To keep the rules in /proc simple I have
1768 * made this apply to all per process world readable and executable
1769 * directories.
1da177e4 1770 */
0b728e19 1771int pid_revalidate(struct dentry *dentry, unsigned int flags)
1da177e4 1772{
34286d66
NP		 1773 struct inode *inode;
1774 struct task_struct *task;
c69e8d9c
DH		 1775 const struct cred *cred;
1776
0b728e19 1777 if (flags & LOOKUP_RCU)
34286d66
NP		 1778 return -ECHILD;
1779
2b0143b5 1780 inode = d_inode(dentry);
34286d66
NP		 1781 task = get_proc_task(inode);
1782
99f89551
EB		 1783 if (task) {
1784 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1785 task_dumpable(task)) {
c69e8d9c
DH		 1786 rcu_read_lock();
1787 cred = __task_cred(task);
1788 inode->i_uid = cred->euid;
1789 inode->i_gid = cred->egid;
1790 rcu_read_unlock();
1da177e4 1791 } else {
dcb0f222
EB		 1792 inode->i_uid = GLOBAL_ROOT_UID;
1793 inode->i_gid = GLOBAL_ROOT_GID;
1da177e4 1794 }
9ee8ab9f 1795 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1796 security_task_to_inode(task, inode);
99f89551 1797 put_task_struct(task);
1da177e4
LT		 1798 return 1;
1799 }
1da177e4
LT		 1800 return 0;
1801}
1802
d855a4b7
ON		 1803static inline bool proc_inode_is_dead(struct inode *inode)
1804{
1805 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
1806}
1807
1dd704b6
DH		 1808int pid_delete_dentry(const struct dentry *dentry)
1809{
1810 /* Is the task we represent dead?
1811 * If so, then don't put the dentry on the lru list,
1812 * kill it immediately.
1813 */
2b0143b5 1814 return proc_inode_is_dead(d_inode(dentry));
1dd704b6
DH		 1815}
1816
6b4e306a 1817const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1818{
1819 .d_revalidate = pid_revalidate,
1820 .d_delete = pid_delete_dentry,
1821};
1822
1823/* Lookups */
1824
1c0d04c9
EB		 1825/*
1826 * Fill a directory entry.
1827 *
1828 * If possible create the dcache entry and derive our inode number and
1829 * file type from dcache entry.
1830 *
1831 * Since all of the proc inode numbers are dynamically generated, the inode
1832 * numbers do not exist until the inode is cache. This means creating the
1833 * the dcache entry in readdir is necessary to keep the inode numbers
1834 * reported by readdir in sync with the inode numbers reported
1835 * by stat.
1836 */
f0c3b509 1837bool proc_fill_cache(struct file *file, struct dir_context *ctx,
6b4e306a 1838 const char *name, int len,
c5141e6d 1839 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1840{
f0c3b509 1841 struct dentry *child, *dir = file->f_path.dentry;
1df98b8b 1842 struct qstr qname = QSTR_INIT(name, len);
61a28784 1843 struct inode *inode;
1df98b8b
AV		 1844 unsigned type;
1845 ino_t ino;
61a28784 1846
1df98b8b 1847 child = d_hash_and_lookup(dir, &qname);
61a28784 1848 if (!child) {
3781764b
AV		 1849 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
1850 child = d_alloc_parallel(dir, &qname, &wq);
1851 if (IS_ERR(child))
1df98b8b 1852 goto end_instantiate;
3781764b
AV		 1853 if (d_in_lookup(child)) {
1854 int err = instantiate(d_inode(dir), child, task, ptr);
1855 d_lookup_done(child);
1856 if (err < 0) {
1857 dput(child);
1858 goto end_instantiate;
1859 }
61a28784
EB		 1860 }
1861 }
2b0143b5 1862 inode = d_inode(child);
147ce699
AV		 1863 ino = inode->i_ino;
1864 type = inode->i_mode >> 12;
61a28784 1865 dput(child);
f0c3b509 1866 return dir_emit(ctx, name, len, ino, type);
1df98b8b
AV		 1867
1868end_instantiate:
1869 return dir_emit(ctx, name, len, 1, DT_UNKNOWN);
61a28784
EB		 1870}
1871
640708a2
PE		 1872/*
1873 * dname_to_vma_addr - maps a dentry name into two unsigned longs
1874 * which represent vma start and end addresses.
1875 */
1876static int dname_to_vma_addr(struct dentry *dentry,
1877 unsigned long *start, unsigned long *end)
1878{
1879 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
1880 return -EINVAL;
1881
1882 return 0;
1883}
1884
0b728e19 1885static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
640708a2
PE		 1886{
1887 unsigned long vm_start, vm_end;
1888 bool exact_vma_exists = false;
1889 struct mm_struct *mm = NULL;
1890 struct task_struct *task;
1891 const struct cred *cred;
1892 struct inode *inode;
1893 int status = 0;
1894
0b728e19 1895 if (flags & LOOKUP_RCU)
640708a2
PE		 1896 return -ECHILD;
1897
2b0143b5 1898 inode = d_inode(dentry);
640708a2
PE		 1899 task = get_proc_task(inode);
1900 if (!task)
1901 goto out_notask;
1902
caaee623 1903 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
2344bec7 1904 if (IS_ERR_OR_NULL(mm))
640708a2
PE		 1905 goto out;
1906
1907 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
1908 down_read(&mm->mmap_sem);
1909 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
1910 up_read(&mm->mmap_sem);
1911 }
1912
1913 mmput(mm);
1914
1915 if (exact_vma_exists) {
1916 if (task_dumpable(task)) {
1917 rcu_read_lock();
1918 cred = __task_cred(task);
1919 inode->i_uid = cred->euid;
1920 inode->i_gid = cred->egid;
1921 rcu_read_unlock();
1922 } else {
dcb0f222
EB		 1923 inode->i_uid = GLOBAL_ROOT_UID;
1924 inode->i_gid = GLOBAL_ROOT_GID;
640708a2
PE		 1925 }
1926 security_task_to_inode(task, inode);
1927 status = 1;
1928 }
1929
1930out:
1931 put_task_struct(task);
1932
1933out_notask:
640708a2
PE		 1934 return status;
1935}
1936
1937static const struct dentry_operations tid_map_files_dentry_operations = {
1938 .d_revalidate = map_files_d_revalidate,
1939 .d_delete = pid_delete_dentry,
1940};
1941
6b255391 1942static int map_files_get_link(struct dentry *dentry, struct path *path)
640708a2
PE		 1943{
1944 unsigned long vm_start, vm_end;
1945 struct vm_area_struct *vma;
1946 struct task_struct *task;
1947 struct mm_struct *mm;
1948 int rc;
1949
1950 rc = -ENOENT;
2b0143b5 1951 task = get_proc_task(d_inode(dentry));
640708a2
PE		 1952 if (!task)
1953 goto out;
1954
1955 mm = get_task_mm(task);
1956 put_task_struct(task);
1957 if (!mm)
1958 goto out;
1959
1960 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
1961 if (rc)
1962 goto out_mmput;
1963
70335abb 1964 rc = -ENOENT;
640708a2
PE		 1965 down_read(&mm->mmap_sem);
1966 vma = find_exact_vma(mm, vm_start, vm_end);
1967 if (vma && vma->vm_file) {
e14748e8 1968 *path = vma_pr_or_file(vma)->f_path;
640708a2
PE		 1969 path_get(path);
1970 rc = 0;
1971 }
1972 up_read(&mm->mmap_sem);
1973
1974out_mmput:
1975 mmput(mm);
1976out:
1977 return rc;
1978}
1979
1980struct map_files_info {
7b540d06 1981 fmode_t mode;
9a87fe0d 1982 unsigned int len;
640708a2
PE		 1983 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
1984};
1985
bdb4d100
CO		 1986/*
1987 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the
1988 * symlinks may be used to bypass permissions on ancestor directories in the
1989 * path to the file in question.
1990 */
1991static const char *
6b255391 1992proc_map_files_get_link(struct dentry *dentry,
fceef393
AV		 1993 struct inode *inode,
1994 struct delayed_call *done)
bdb4d100
CO		 1995{
1996 if (!capable(CAP_SYS_ADMIN))
1997 return ERR_PTR(-EPERM);
1998
fceef393 1999 return proc_pid_get_link(dentry, inode, done);
bdb4d100
CO		 2000}
2001
2002/*
6b255391 2003 * Identical to proc_pid_link_inode_operations except for get_link()
bdb4d100
CO		 2004 */
2005static const struct inode_operations proc_map_files_link_inode_operations = {
2006 .readlink = proc_pid_readlink,
6b255391 2007 .get_link = proc_map_files_get_link,
bdb4d100
CO		 2008 .setattr = proc_setattr,
2009};
2010
c52a47ac 2011static int
640708a2
PE		 2012proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2013 struct task_struct *task, const void *ptr)
2014{
7b540d06 2015 fmode_t mode = (fmode_t)(unsigned long)ptr;
640708a2
PE		 2016 struct proc_inode *ei;
2017 struct inode *inode;
2018
db978da8
AG		 2019 inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK |
2020 ((mode & FMODE_READ ) ? S_IRUSR : 0) |
2021 ((mode & FMODE_WRITE) ? S_IWUSR : 0));
640708a2 2022 if (!inode)
c52a47ac 2023 return -ENOENT;
640708a2
PE		 2024
2025 ei = PROC_I(inode);
6b255391 2026 ei->op.proc_get_link = map_files_get_link;
640708a2 2027
bdb4d100 2028 inode->i_op = &proc_map_files_link_inode_operations;
640708a2 2029 inode->i_size = 64;
640708a2
PE		 2030
2031 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2032 d_add(dentry, inode);
2033
c52a47ac 2034 return 0;
640708a2
PE		 2035}
2036
2037static struct dentry *proc_map_files_lookup(struct inode *dir,
00cd8dd3 2038 struct dentry *dentry, unsigned int flags)
640708a2
PE		 2039{
2040 unsigned long vm_start, vm_end;
2041 struct vm_area_struct *vma;
2042 struct task_struct *task;
c52a47ac 2043 int result;
640708a2
PE		 2044 struct mm_struct *mm;
2045
c52a47ac 2046 result = -ENOENT;
640708a2
PE		 2047 task = get_proc_task(dir);
2048 if (!task)
2049 goto out;
2050
c52a47ac 2051 result = -EACCES;
caaee623 2052 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
640708a2
PE		 2053 goto out_put_task;
2054
c52a47ac 2055 result = -ENOENT;
640708a2 2056 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
eb94cd96 2057 goto out_put_task;
640708a2
PE		 2058
2059 mm = get_task_mm(task);
2060 if (!mm)
eb94cd96 2061 goto out_put_task;
640708a2
PE		 2062
2063 down_read(&mm->mmap_sem);
2064 vma = find_exact_vma(mm, vm_start, vm_end);
2065 if (!vma)
2066 goto out_no_vma;
2067
05f56484
SK		 2068 if (vma->vm_file)
2069 result = proc_map_files_instantiate(dir, dentry, task,
2070 (void *)(unsigned long)vma->vm_file->f_mode);
640708a2
PE		 2071
2072out_no_vma:
2073 up_read(&mm->mmap_sem);
2074 mmput(mm);
640708a2
PE		 2075out_put_task:
2076 put_task_struct(task);
2077out:
c52a47ac 2078 return ERR_PTR(result);
640708a2
PE		 2079}
2080
2081static const struct inode_operations proc_map_files_inode_operations = {
2082 .lookup = proc_map_files_lookup,
2083 .permission = proc_fd_permission,
2084 .setattr = proc_setattr,
2085};
2086
2087static int
f0c3b509 2088proc_map_files_readdir(struct file *file, struct dir_context *ctx)
640708a2 2089{
640708a2
PE		 2090 struct vm_area_struct *vma;
2091 struct task_struct *task;
2092 struct mm_struct *mm;
f0c3b509
AV		 2093 unsigned long nr_files, pos, i;
2094 struct flex_array *fa = NULL;
2095 struct map_files_info info;
2096 struct map_files_info *p;
640708a2
PE		 2097 int ret;
2098
640708a2 2099 ret = -ENOENT;
f0c3b509 2100 task = get_proc_task(file_inode(file));
640708a2
PE		 2101 if (!task)
2102 goto out;
2103
2104 ret = -EACCES;
caaee623 2105 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
640708a2
PE		 2106 goto out_put_task;
2107
2108 ret = 0;
f0c3b509
AV		 2109 if (!dir_emit_dots(file, ctx))
2110 goto out_put_task;
640708a2 2111
f0c3b509
AV		 2112 mm = get_task_mm(task);
2113 if (!mm)
2114 goto out_put_task;
2115 down_read(&mm->mmap_sem);
640708a2 2116
f0c3b509 2117 nr_files = 0;
640708a2 2118
f0c3b509
AV		 2119 /*
2120 * We need two passes here:
2121 *
2122 * 1) Collect vmas of mapped files with mmap_sem taken
2123 * 2) Release mmap_sem and instantiate entries
2124 *
2125 * otherwise we get lockdep complained, since filldir()
2126 * routine might require mmap_sem taken in might_fault().
2127 */
640708a2 2128
f0c3b509
AV		 2129 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2130 if (vma->vm_file && ++pos > ctx->pos)
2131 nr_files++;
2132 }
2133
2134 if (nr_files) {
2135 fa = flex_array_alloc(sizeof(info), nr_files,
2136 GFP_KERNEL);
2137 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2138 GFP_KERNEL)) {
2139 ret = -ENOMEM;
2140 if (fa)
2141 flex_array_free(fa);
2142 up_read(&mm->mmap_sem);
2143 mmput(mm);
2144 goto out_put_task;
640708a2 2145 }
f0c3b509
AV		 2146 for (i = 0, vma = mm->mmap, pos = 2; vma;
2147 vma = vma->vm_next) {
2148 if (!vma->vm_file)
2149 continue;
2150 if (++pos <= ctx->pos)
2151 continue;
2152
2153 info.mode = vma->vm_file->f_mode;
2154 info.len = snprintf(info.name,
2155 sizeof(info.name), "%lx-%lx",
2156 vma->vm_start, vma->vm_end);
2157 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2158 BUG();
640708a2 2159 }
640708a2 2160 }
f0c3b509
AV		 2161 up_read(&mm->mmap_sem);
2162
2163 for (i = 0; i < nr_files; i++) {
2164 p = flex_array_get(fa, i);
2165 if (!proc_fill_cache(file, ctx,
2166 p->name, p->len,
2167 proc_map_files_instantiate,
2168 task,
2169 (void *)(unsigned long)p->mode))
2170 break;
2171 ctx->pos++;
640708a2 2172 }
f0c3b509
AV		 2173 if (fa)
2174 flex_array_free(fa);
2175 mmput(mm);
640708a2 2176
640708a2
PE		 2177out_put_task:
2178 put_task_struct(task);
2179out:
2180 return ret;
2181}
2182
2183static const struct file_operations proc_map_files_operations = {
2184 .read = generic_read_dir,
f50752ea
AV		 2185 .iterate_shared = proc_map_files_readdir,
2186 .llseek = generic_file_llseek,
640708a2
PE		 2187};
2188
b5946bea 2189#ifdef CONFIG_CHECKPOINT_RESTORE
48f6a7a5
PE		 2190struct timers_private {
2191 struct pid *pid;
2192 struct task_struct *task;
2193 struct sighand_struct *sighand;
57b8015e 2194 struct pid_namespace *ns;
48f6a7a5
PE		 2195 unsigned long flags;
2196};
2197
2198static void *timers_start(struct seq_file *m, loff_t *pos)
2199{
2200 struct timers_private *tp = m->private;
2201
2202 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2203 if (!tp->task)
2204 return ERR_PTR(-ESRCH);
2205
2206 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2207 if (!tp->sighand)
2208 return ERR_PTR(-ESRCH);
2209
2210 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2211}
2212
2213static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2214{
2215 struct timers_private *tp = m->private;
2216 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2217}
2218
2219static void timers_stop(struct seq_file *m, void *v)
2220{
2221 struct timers_private *tp = m->private;
2222
2223 if (tp->sighand) {
2224 unlock_task_sighand(tp->task, &tp->flags);
2225 tp->sighand = NULL;
2226 }
2227
2228 if (tp->task) {
2229 put_task_struct(tp->task);
2230 tp->task = NULL;
2231 }
2232}
2233
2234static int show_timer(struct seq_file *m, void *v)
2235{
2236 struct k_itimer *timer;
57b8015e
PE		 2237 struct timers_private *tp = m->private;
2238 int notify;
cedbccab 2239 static const char * const nstr[] = {
57b8015e
PE		 2240 [SIGEV_SIGNAL] = "signal",
2241 [SIGEV_NONE] = "none",
2242 [SIGEV_THREAD] = "thread",
2243 };
48f6a7a5
PE		 2244
2245 timer = list_entry((struct list_head *)v, struct k_itimer, list);
57b8015e
PE		 2246 notify = timer->it_sigev_notify;
2247
48f6a7a5 2248 seq_printf(m, "ID: %d\n", timer->it_id);
25ce3191
JP		 2249 seq_printf(m, "signal: %d/%p\n",
2250 timer->sigq->info.si_signo,
2251 timer->sigq->info.si_value.sival_ptr);
57b8015e 2252 seq_printf(m, "notify: %s/%s.%d\n",
25ce3191
JP		 2253 nstr[notify & ~SIGEV_THREAD_ID],
2254 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2255 pid_nr_ns(timer->it_pid, tp->ns));
15ef0298 2256 seq_printf(m, "ClockID: %d\n", timer->it_clock);
48f6a7a5
PE		 2257
2258 return 0;
2259}
2260
2261static const struct seq_operations proc_timers_seq_ops = {
2262 .start = timers_start,
2263 .next = timers_next,
2264 .stop = timers_stop,
2265 .show = show_timer,
2266};
2267
2268static int proc_timers_open(struct inode *inode, struct file *file)
2269{
2270 struct timers_private *tp;
2271
2272 tp = __seq_open_private(file, &proc_timers_seq_ops,
2273 sizeof(struct timers_private));
2274 if (!tp)
2275 return -ENOMEM;
2276
2277 tp->pid = proc_pid(inode);
57b8015e 2278 tp->ns = inode->i_sb->s_fs_info;
48f6a7a5
PE		 2279 return 0;
2280}
2281
2282static const struct file_operations proc_timers_operations = {
2283 .open = proc_timers_open,
2284 .read = seq_read,
2285 .llseek = seq_lseek,
2286 .release = seq_release_private,
2287};
b5946bea 2288#endif
640708a2 2289
5de23d43
JS		 2290static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2291 size_t count, loff_t *offset)
2292{
2293 struct inode *inode = file_inode(file);
2294 struct task_struct *p;
2295 u64 slack_ns;
2296 int err;
2297
2298 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2299 if (err < 0)
2300 return err;
2301
2302 p = get_proc_task(inode);
2303 if (!p)
2304 return -ESRCH;
2305
4b2bd5fe
JS		 2306 if (p != current) {
2307 if (!capable(CAP_SYS_NICE)) {
2308 count = -EPERM;
2309 goto out;
2310 }
5de23d43 2311
4b2bd5fe
JS		 2312 err = security_task_setscheduler(p);
2313 if (err) {
2314 count = err;
2315 goto out;
2316 }
904763e1
JS		 2317 }
2318
7abbaf94
JS		 2319 task_lock(p);
2320 if (slack_ns == 0)
2321 p->timer_slack_ns = p->default_timer_slack_ns;
2322 else
2323 p->timer_slack_ns = slack_ns;
2324 task_unlock(p);
2325
2326out:
5de23d43
JS		 2327 put_task_struct(p);
2328
2329 return count;
2330}
2331
2332static int timerslack_ns_show(struct seq_file *m, void *v)
2333{
2334 struct inode *inode = m->private;
2335 struct task_struct *p;
7abbaf94 2336 int err = 0;
5de23d43
JS		 2337
2338 p = get_proc_task(inode);
2339 if (!p)
2340 return -ESRCH;
2341
4b2bd5fe 2342 if (p != current) {
5de23d43 2343
4b2bd5fe
JS		 2344 if (!capable(CAP_SYS_NICE)) {
2345 err = -EPERM;
2346 goto out;
2347 }
2348 err = security_task_getscheduler(p);
2349 if (err)
2350 goto out;
2351 }
904763e1 2352
7abbaf94
JS		 2353 task_lock(p);
2354 seq_printf(m, "%llu\n", p->timer_slack_ns);
2355 task_unlock(p);
2356
2357out:
5de23d43
JS		 2358 put_task_struct(p);
2359
2360 return err;
2361}
2362
2363static int timerslack_ns_open(struct inode *inode, struct file *filp)
2364{
2365 return single_open(filp, timerslack_ns_show, inode);
2366}
2367
2368static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2369 .open = timerslack_ns_open,
2370 .read = seq_read,
2371 .write = timerslack_ns_write,
2372 .llseek = seq_lseek,
2373 .release = single_release,
2374};
2375
c52a47ac 2376static int proc_pident_instantiate(struct inode *dir,
c5141e6d 2377 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2378{
c5141e6d 2379 const struct pid_entry *p = ptr;
444ceed8
EB		 2380 struct inode *inode;
2381 struct proc_inode *ei;
444ceed8 2382
db978da8 2383 inode = proc_pid_make_inode(dir->i_sb, task, p->mode);
444ceed8
EB		 2384 if (!inode)
2385 goto out;
2386
2387 ei = PROC_I(inode);
444ceed8 2388 if (S_ISDIR(inode->i_mode))
bfe86848 2389 set_nlink(inode, 2); /* Use getattr to fix if necessary */
444ceed8
EB		 2390 if (p->iop)
2391 inode->i_op = p->iop;
2392 if (p->fop)
2393 inode->i_fop = p->fop;
2394 ei->op = p->op;
fb045adb 2395 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 2396 d_add(dentry, inode);
2397 /* Close the race of the process dying before we return the dentry */
0b728e19 2398 if (pid_revalidate(dentry, 0))
c52a47ac 2399 return 0;
444ceed8 2400out:
c52a47ac 2401 return -ENOENT;
444ceed8
EB		 2402}
2403
1da177e4
LT		 2404static struct dentry *proc_pident_lookup(struct inode *dir,
2405 struct dentry *dentry,
c5141e6d 2406 const struct pid_entry *ents,
7bcd6b0e 2407 unsigned int nents)
1da177e4 2408{
c52a47ac 2409 int error;
99f89551 2410 struct task_struct *task = get_proc_task(dir);
c5141e6d 2411 const struct pid_entry *p, *last;
1da177e4 2412
c52a47ac 2413 error = -ENOENT;
1da177e4 2414
99f89551
EB		 2415 if (!task)
2416 goto out_no_task;
1da177e4 2417
20cdc894
EB		 2418 /*
2419 * Yes, it does not scale. And it should not. Don't add
2420 * new entries into /proc/<tgid>/ without very good reasons.
2421 */
bac5f5d5
AD		 2422 last = &ents[nents];
2423 for (p = ents; p < last; p++) {
1da177e4
LT		 2424 if (p->len != dentry->d_name.len)
2425 continue;
2426 if (!memcmp(dentry->d_name.name, p->name, p->len))
2427 break;
2428 }
bac5f5d5 2429 if (p >= last)
1da177e4
LT		 2430 goto out;
2431
444ceed8 2432 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2433out:
99f89551
EB		 2434 put_task_struct(task);
2435out_no_task:
c52a47ac 2436 return ERR_PTR(error);
1da177e4
LT		 2437}
2438
f0c3b509 2439static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
c5141e6d 2440 const struct pid_entry *ents, unsigned int nents)
28a6d671 2441{
f0c3b509
AV		 2442 struct task_struct *task = get_proc_task(file_inode(file));
2443 const struct pid_entry *p;
28a6d671 2444
28a6d671 2445 if (!task)
f0c3b509 2446 return -ENOENT;
28a6d671 2447
f0c3b509
AV		 2448 if (!dir_emit_dots(file, ctx))
2449 goto out;
2450
2451 if (ctx->pos >= nents + 2)
2452 goto out;
28a6d671 2453
bac5f5d5 2454 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
f0c3b509
AV		 2455 if (!proc_fill_cache(file, ctx, p->name, p->len,
2456 proc_pident_instantiate, task, p))
2457 break;
2458 ctx->pos++;
2459 }
28a6d671 2460out:
61a28784 2461 put_task_struct(task);
f0c3b509 2462 return 0;
1da177e4
LT		 2463}
2464
28a6d671
EB		 2465#ifdef CONFIG_SECURITY
2466static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2467 size_t count, loff_t *ppos)
2468{
496ad9aa 2469 struct inode * inode = file_inode(file);
04ff9708 2470 char *p = NULL;
28a6d671
EB		 2471 ssize_t length;
2472 struct task_struct *task = get_proc_task(inode);
2473
28a6d671 2474 if (!task)
04ff9708 2475 return -ESRCH;
28a6d671
EB		 2476
2477 length = security_getprocattr(task,
2fddfeef 2478 (char*)file->f_path.dentry->d_name.name,
04ff9708 2479 &p);
28a6d671 2480 put_task_struct(task);
04ff9708
AV		 2481 if (length > 0)
2482 length = simple_read_from_buffer(buf, count, ppos, p, length);
2483 kfree(p);
28a6d671 2484 return length;
1da177e4
LT		 2485}
2486
28a6d671
EB		 2487static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2488 size_t count, loff_t *ppos)
2489{
496ad9aa 2490 struct inode * inode = file_inode(file);
bb646cdb 2491 void *page;
28a6d671
EB		 2492 ssize_t length;
2493 struct task_struct *task = get_proc_task(inode);
2494
2495 length = -ESRCH;
2496 if (!task)
2497 goto out_no_task;
2498 if (count > PAGE_SIZE)
2499 count = PAGE_SIZE;
2500
2501 /* No partial writes. */
2502 length = -EINVAL;
2503 if (*ppos != 0)
2504 goto out;
2505
bb646cdb
AV		 2506 page = memdup_user(buf, count);
2507 if (IS_ERR(page)) {
2508 length = PTR_ERR(page);
28a6d671 2509 goto out;
bb646cdb 2510 }
28a6d671 2511
107db7c7 2512 /* Guard against adverse ptrace interaction */
9b1bf12d 2513 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
107db7c7
DH		 2514 if (length < 0)
2515 goto out_free;
2516
28a6d671 2517 length = security_setprocattr(task,
2fddfeef 2518 (char*)file->f_path.dentry->d_name.name,
bb646cdb 2519 page, count);
9b1bf12d 2520 mutex_unlock(&task->signal->cred_guard_mutex);
28a6d671 2521out_free:
bb646cdb 2522 kfree(page);
28a6d671
EB		 2523out:
2524 put_task_struct(task);
2525out_no_task:
2526 return length;
2527}
2528
00977a59 2529static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2530 .read = proc_pid_attr_read,
2531 .write = proc_pid_attr_write,
87df8424 2532 .llseek = generic_file_llseek,
28a6d671
EB		 2533};
2534
c5141e6d 2535static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2536 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2537 REG("prev", S_IRUGO, proc_pid_attr_operations),
2538 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2539 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2540 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2541 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2542};
2543
f0c3b509 2544static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
28a6d671 2545{
f0c3b509
AV		 2546 return proc_pident_readdir(file, ctx,
2547 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2548}
2549
00977a59 2550static const struct file_operations proc_attr_dir_operations = {
1da177e4 2551 .read = generic_read_dir,
f50752ea
AV		 2552 .iterate_shared = proc_attr_dir_readdir,
2553 .llseek = generic_file_llseek,
1da177e4
LT		 2554};
2555
72d9dcfc 2556static struct dentry *proc_attr_dir_lookup(struct inode *dir,
00cd8dd3 2557 struct dentry *dentry, unsigned int flags)
28a6d671 2558{
7bcd6b0e
EB		 2559 return proc_pident_lookup(dir, dentry,
2560 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2561}
2562
c5ef1c42 2563static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2564 .lookup = proc_attr_dir_lookup,
99f89551 2565 .getattr = pid_getattr,
6d76fa58 2566 .setattr = proc_setattr,
1da177e4
LT		 2567};
2568
28a6d671
EB		 2569#endif
2570
698ba7b5 2571#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2572static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2573 size_t count, loff_t *ppos)
2574{
496ad9aa 2575 struct task_struct *task = get_proc_task(file_inode(file));
3cb4a0bb
KH		 2576 struct mm_struct *mm;
2577 char buffer[PROC_NUMBUF];
2578 size_t len;
2579 int ret;
2580
2581 if (!task)
2582 return -ESRCH;
2583
2584 ret = 0;
2585 mm = get_task_mm(task);
2586 if (mm) {
2587 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2588 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2589 MMF_DUMP_FILTER_SHIFT));
2590 mmput(mm);
2591 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2592 }
2593
2594 put_task_struct(task);
2595
2596 return ret;
2597}
2598
2599static ssize_t proc_coredump_filter_write(struct file *file,
2600 const char __user *buf,
2601 size_t count,
2602 loff_t *ppos)
2603{
2604 struct task_struct *task;
2605 struct mm_struct *mm;
3cb4a0bb
KH		 2606 unsigned int val;
2607 int ret;
2608 int i;
2609 unsigned long mask;
2610
774636e1
AD		 2611 ret = kstrtouint_from_user(buf, count, 0, &val);
2612 if (ret < 0)
2613 return ret;
3cb4a0bb
KH		 2614
2615 ret = -ESRCH;
496ad9aa 2616 task = get_proc_task(file_inode(file));
3cb4a0bb
KH		 2617 if (!task)
2618 goto out_no_task;
2619
3cb4a0bb
KH		 2620 mm = get_task_mm(task);
2621 if (!mm)
2622 goto out_no_mm;
41a0c249 2623 ret = 0;
3cb4a0bb
KH		 2624
2625 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2626 if (val & mask)
2627 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2628 else
2629 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2630 }
2631
2632 mmput(mm);
2633 out_no_mm:
2634 put_task_struct(task);
2635 out_no_task:
774636e1
AD		 2636 if (ret < 0)
2637 return ret;
2638 return count;
3cb4a0bb
KH		 2639}
2640
2641static const struct file_operations proc_coredump_filter_operations = {
2642 .read = proc_coredump_filter_read,
2643 .write = proc_coredump_filter_write,
87df8424 2644 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2645};
2646#endif
2647
aba76fdb 2648#ifdef CONFIG_TASK_IO_ACCOUNTING
19aadc98 2649static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
297c5d92 2650{
940389b8 2651 struct task_io_accounting acct = task->ioac;
5995477a 2652 unsigned long flags;
293eb1e7 2653 int result;
5995477a 2654
293eb1e7
VK		 2655 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2656 if (result)
2657 return result;
2658
caaee623 2659 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
293eb1e7
VK		 2660 result = -EACCES;
2661 goto out_unlock;
2662 }
1d1221f3 2663
5995477a
AR		 2664 if (whole && lock_task_sighand(task, &flags)) {
2665 struct task_struct *t = task;
2666
2667 task_io_accounting_add(&acct, &task->signal->ioac);
2668 while_each_thread(task, t)
2669 task_io_accounting_add(&acct, &t->ioac);
2670
2671 unlock_task_sighand(task, &flags);
297c5d92 2672 }
25ce3191
JP		 2673 seq_printf(m,
2674 "rchar: %llu\n"
2675 "wchar: %llu\n"
2676 "syscr: %llu\n"
2677 "syscw: %llu\n"
2678 "read_bytes: %llu\n"
2679 "write_bytes: %llu\n"
2680 "cancelled_write_bytes: %llu\n",
2681 (unsigned long long)acct.rchar,
2682 (unsigned long long)acct.wchar,
2683 (unsigned long long)acct.syscr,
2684 (unsigned long long)acct.syscw,
2685 (unsigned long long)acct.read_bytes,
2686 (unsigned long long)acct.write_bytes,
2687 (unsigned long long)acct.cancelled_write_bytes);
2688 result = 0;
2689
293eb1e7
VK		 2690out_unlock:
2691 mutex_unlock(&task->signal->cred_guard_mutex);
2692 return result;
297c5d92
AR		 2693}
2694
19aadc98
AD		 2695static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2696 struct pid *pid, struct task_struct *task)
297c5d92 2697{
19aadc98 2698 return do_io_accounting(task, m, 0);
aba76fdb 2699}
297c5d92 2700
19aadc98
AD		 2701static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2702 struct pid *pid, struct task_struct *task)
297c5d92 2703{
19aadc98 2704 return do_io_accounting(task, m, 1);
297c5d92
AR		 2705}
2706#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2707
22d917d8
EB		 2708#ifdef CONFIG_USER_NS
2709static int proc_id_map_open(struct inode *inode, struct file *file,
ccf94f1b 2710 const struct seq_operations *seq_ops)
22d917d8
EB		 2711{
2712 struct user_namespace *ns = NULL;
2713 struct task_struct *task;
2714 struct seq_file *seq;
2715 int ret = -EINVAL;
2716
2717 task = get_proc_task(inode);
2718 if (task) {
2719 rcu_read_lock();
2720 ns = get_user_ns(task_cred_xxx(task, user_ns));
2721 rcu_read_unlock();
2722 put_task_struct(task);
2723 }
2724 if (!ns)
2725 goto err;
2726
2727 ret = seq_open(file, seq_ops);
2728 if (ret)
2729 goto err_put_ns;
2730
2731 seq = file->private_data;
2732 seq->private = ns;
2733
2734 return 0;
2735err_put_ns:
2736 put_user_ns(ns);
2737err:
2738 return ret;
2739}
2740
2741static int proc_id_map_release(struct inode *inode, struct file *file)
2742{
2743 struct seq_file *seq = file->private_data;
2744 struct user_namespace *ns = seq->private;
2745 put_user_ns(ns);
2746 return seq_release(inode, file);
2747}
2748
2749static int proc_uid_map_open(struct inode *inode, struct file *file)
2750{
2751 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2752}
2753
2754static int proc_gid_map_open(struct inode *inode, struct file *file)
2755{
2756 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2757}
2758
f76d207a
EB		 2759static int proc_projid_map_open(struct inode *inode, struct file *file)
2760{
2761 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
2762}
2763
22d917d8
EB		 2764static const struct file_operations proc_uid_map_operations = {
2765 .open = proc_uid_map_open,
2766 .write = proc_uid_map_write,
2767 .read = seq_read,
2768 .llseek = seq_lseek,
2769 .release = proc_id_map_release,
2770};
2771
2772static const struct file_operations proc_gid_map_operations = {
2773 .open = proc_gid_map_open,
2774 .write = proc_gid_map_write,
2775 .read = seq_read,
2776 .llseek = seq_lseek,
2777 .release = proc_id_map_release,
2778};
f76d207a
EB		 2779
2780static const struct file_operations proc_projid_map_operations = {
2781 .open = proc_projid_map_open,
2782 .write = proc_projid_map_write,
2783 .read = seq_read,
2784 .llseek = seq_lseek,
2785 .release = proc_id_map_release,
2786};
9cc46516
EB		 2787
2788static int proc_setgroups_open(struct inode *inode, struct file *file)
2789{
2790 struct user_namespace *ns = NULL;
2791 struct task_struct *task;
2792 int ret;
2793
2794 ret = -ESRCH;
2795 task = get_proc_task(inode);
2796 if (task) {
2797 rcu_read_lock();
2798 ns = get_user_ns(task_cred_xxx(task, user_ns));
2799 rcu_read_unlock();
2800 put_task_struct(task);
2801 }
2802 if (!ns)
2803 goto err;
2804
2805 if (file->f_mode & FMODE_WRITE) {
2806 ret = -EACCES;
2807 if (!ns_capable(ns, CAP_SYS_ADMIN))
2808 goto err_put_ns;
2809 }
2810
2811 ret = single_open(file, &proc_setgroups_show, ns);
2812 if (ret)
2813 goto err_put_ns;
2814
2815 return 0;
2816err_put_ns:
2817 put_user_ns(ns);
2818err:
2819 return ret;
2820}
2821
2822static int proc_setgroups_release(struct inode *inode, struct file *file)
2823{
2824 struct seq_file *seq = file->private_data;
2825 struct user_namespace *ns = seq->private;
2826 int ret = single_release(inode, file);
2827 put_user_ns(ns);
2828 return ret;
2829}
2830
2831static const struct file_operations proc_setgroups_operations = {
2832 .open = proc_setgroups_open,
2833 .write = proc_setgroups_write,
2834 .read = seq_read,
2835 .llseek = seq_lseek,
2836 .release = proc_setgroups_release,
2837};
22d917d8
EB		 2838#endif /* CONFIG_USER_NS */
2839
47830723
KC		 2840static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2841 struct pid *pid, struct task_struct *task)
2842{
a9712bc1
AV		 2843 int err = lock_trace(task);
2844 if (!err) {
2845 seq_printf(m, "%08x\n", task->personality);
2846 unlock_trace(task);
2847 }
2848 return err;
47830723
KC		 2849}
2850
28a6d671
EB		 2851/*
2852 * Thread groups
2853 */
00977a59 2854static const struct file_operations proc_task_operations;
c5ef1c42 2855static const struct inode_operations proc_task_inode_operations;
20cdc894 2856
c5141e6d 2857static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2858 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2859 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
640708a2 2860 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
631f9c18 2861 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 2862 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
b2211a36 2863#ifdef CONFIG_NET
631f9c18 2864 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 2865#endif
631f9c18 2866 REG("environ", S_IRUSR, proc_environ_operations),
c5317167 2867 REG("auxv", S_IRUSR, proc_auxv_operations),
631f9c18 2868 ONE("status", S_IRUGO, proc_pid_status),
35a35046 2869 ONE("personality", S_IRUSR, proc_pid_personality),
1c963eb1 2870 ONE("limits", S_IRUGO, proc_pid_limits),
43ae34cb 2871#ifdef CONFIG_SCHED_DEBUG
631f9c18 2872 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
5091faa4
MG		 2873#endif
2874#ifdef CONFIG_SCHED_AUTOGROUP
2875 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
ebcb6734 2876#endif
4614a696 2877 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 2878#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
09d93bd6 2879 ONE("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 2880#endif
c2c0bb44 2881 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
631f9c18
AD		 2882 ONE("stat", S_IRUGO, proc_tgid_stat),
2883 ONE("statm", S_IRUGO, proc_pid_statm),
b7643757 2884 REG("maps", S_IRUGO, proc_pid_maps_operations),
28a6d671 2885#ifdef CONFIG_NUMA
b7643757 2886 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
28a6d671 2887#endif
631f9c18
AD		 2888 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2889 LNK("cwd", proc_cwd_link),
2890 LNK("root", proc_root_link),
2891 LNK("exe", proc_exe_link),
2892 REG("mounts", S_IRUGO, proc_mounts_operations),
2893 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2894 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 2895#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18 2896 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
b7643757 2897 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
32ed74a4 2898 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 2899#endif
2900#ifdef CONFIG_SECURITY
631f9c18 2901 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 2902#endif
2903#ifdef CONFIG_KALLSYMS
edfcd606 2904 ONE("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 2905#endif
2ec220e2 2906#ifdef CONFIG_STACKTRACE
35a35046 2907 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671 2908#endif
5968cece 2909#ifdef CONFIG_SCHED_INFO
f6e826ca 2910 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 2911#endif
9745512c 2912#ifdef CONFIG_LATENCYTOP
631f9c18 2913 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 2914#endif
8793d854 2915#ifdef CONFIG_PROC_PID_CPUSET
52de4779 2916 ONE("cpuset", S_IRUGO, proc_cpuset_show),
a424316c
PM		 2917#endif
2918#ifdef CONFIG_CGROUPS
006f4ac4 2919 ONE("cgroup", S_IRUGO, proc_cgroup_show),
28a6d671 2920#endif
6ba51e37 2921 ONE("oom_score", S_IRUGO, proc_oom_score),
fa0cbbf1 2922 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
a63d83f4 2923 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 2924#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 2925 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2926 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 2927#endif
f4f154fd 2928#ifdef CONFIG_FAULT_INJECTION
631f9c18 2929 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 2930#endif
698ba7b5 2931#ifdef CONFIG_ELF_CORE
631f9c18 2932 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 2933#endif
aba76fdb 2934#ifdef CONFIG_TASK_IO_ACCOUNTING
19aadc98 2935 ONE("io", S_IRUSR, proc_tgid_io_accounting),
aba76fdb 2936#endif
f133ecca 2937#ifdef CONFIG_HARDWALL
d962c144 2938 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
f133ecca 2939#endif
22d917d8
EB		 2940#ifdef CONFIG_USER_NS
2941 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
2942 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
f76d207a 2943 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
9cc46516 2944 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
22d917d8 2945#endif
48f6a7a5
PE		 2946#ifdef CONFIG_CHECKPOINT_RESTORE
2947 REG("timers", S_IRUGO, proc_timers_operations),
2948#endif
5de23d43 2949 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
28a6d671 2950};
1da177e4 2951
f0c3b509 2952static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
1da177e4 2953{
f0c3b509
AV		 2954 return proc_pident_readdir(file, ctx,
2955 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2956}
2957
00977a59 2958static const struct file_operations proc_tgid_base_operations = {
1da177e4 2959 .read = generic_read_dir,
f50752ea
AV		 2960 .iterate_shared = proc_tgid_base_readdir,
2961 .llseek = generic_file_llseek,
1da177e4
LT		 2962};
2963
00cd8dd3
AV		 2964static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
2965{
7bcd6b0e
EB		 2966 return proc_pident_lookup(dir, dentry,
2967 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2968}
2969
c5ef1c42 2970static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 2971 .lookup = proc_tgid_base_lookup,
99f89551 2972 .getattr = pid_getattr,
6d76fa58 2973 .setattr = proc_setattr,
0499680a 2974 .permission = proc_pid_permission,
1da177e4 2975};
1da177e4 2976
60347f67 2977static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 2978{
48e6484d 2979 struct dentry *dentry, *leader, *dir;
8578cea7 2980 char buf[PROC_NUMBUF];
48e6484d
EB		 2981 struct qstr name;
2982
2983 name.name = buf;
60347f67 2984 name.len = snprintf(buf, sizeof(buf), "%d", pid);
4f522a24 2985 /* no ->d_hash() rejects on procfs */
60347f67 2986 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 2987 if (dentry) {
bbd51924 2988 d_invalidate(dentry);
48e6484d
EB		 2989 dput(dentry);
2990 }
1da177e4 2991
c35a7f18
ON		 2992 if (pid == tgid)
2993 return;
2994
48e6484d 2995 name.name = buf;
60347f67
PE		 2996 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2997 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 2998 if (!leader)
2999 goto out;
1da177e4 3000
48e6484d
EB		 3001 name.name = "task";
3002 name.len = strlen(name.name);
3003 dir = d_hash_and_lookup(leader, &name);
3004 if (!dir)
3005 goto out_put_leader;
3006
3007 name.name = buf;
60347f67 3008 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 3009 dentry = d_hash_and_lookup(dir, &name);
3010 if (dentry) {
bbd51924 3011 d_invalidate(dentry);
48e6484d 3012 dput(dentry);
1da177e4 3013 }
48e6484d
EB		 3014
3015 dput(dir);
3016out_put_leader:
3017 dput(leader);
3018out:
3019 return;
1da177e4
LT		 3020}
3021
0895e91d
RD		 3022/**
3023 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3024 * @task: task that should be flushed.
3025 *
3026 * When flushing dentries from proc, one needs to flush them from global
60347f67 3027 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 3028 * in. This call is supposed to do all of this job.
3029 *
3030 * Looks in the dcache for
3031 * /proc/@pid
3032 * /proc/@tgid/task/@pid
3033 * if either directory is present flushes it and all of it'ts children
3034 * from the dcache.
3035 *
3036 * It is safe and reasonable to cache /proc entries for a task until
3037 * that task exits. After that they just clog up the dcache with
3038 * useless entries, possibly causing useful dcache entries to be
3039 * flushed instead. This routine is proved to flush those useless
3040 * dcache entries at process exit time.
3041 *
3042 * NOTE: This routine is just an optimization so it does not guarantee
3043 * that no dcache entries will exist at process exit time it
3044 * just makes it very unlikely that any will persist.
60347f67
PE		 3045 */
3046
3047void proc_flush_task(struct task_struct *task)
3048{
9fcc2d15 3049 int i;
9b4d1cbe 3050 struct pid *pid, *tgid;
130f77ec
PE		 3051 struct upid *upid;
3052
130f77ec 3053 pid = task_pid(task);
9b4d1cbe 3054 tgid = task_tgid(task);
130f77ec 3055
9fcc2d15 3056 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 3057 upid = &pid->numbers[i];
3058 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 3059 tgid->numbers[i].nr);
130f77ec 3060 }
60347f67
PE		 3061}
3062
c52a47ac
AV		 3063static int proc_pid_instantiate(struct inode *dir,
3064 struct dentry * dentry,
3065 struct task_struct *task, const void *ptr)
444ceed8 3066{
444ceed8
EB		 3067 struct inode *inode;
3068
db978da8 3069 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
444ceed8
EB		 3070 if (!inode)
3071 goto out;
3072
444ceed8
EB		 3073 inode->i_op = &proc_tgid_base_inode_operations;
3074 inode->i_fop = &proc_tgid_base_operations;
3075 inode->i_flags|=S_IMMUTABLE;
aed54175 3076
1270dd8d 3077 set_nlink(inode, nlink_tgid);
444ceed8 3078
fb045adb 3079 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3080
3081 d_add(dentry, inode);
3082 /* Close the race of the process dying before we return the dentry */
0b728e19 3083 if (pid_revalidate(dentry, 0))
c52a47ac 3084 return 0;
444ceed8 3085out:
c52a47ac 3086 return -ENOENT;
444ceed8
EB		 3087}
3088
00cd8dd3 3089struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
1da177e4 3090{
335eb531 3091 int result = -ENOENT;
1da177e4 3092 struct task_struct *task;
1da177e4 3093 unsigned tgid;
b488893a 3094 struct pid_namespace *ns;
1da177e4 3095
dbcdb504 3096 tgid = name_to_int(&dentry->d_name);
1da177e4
LT		 3097 if (tgid == ~0U)
3098 goto out;
3099
b488893a 3100 ns = dentry->d_sb->s_fs_info;
de758734 3101 rcu_read_lock();
b488893a 3102 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 3103 if (task)
3104 get_task_struct(task);
de758734 3105 rcu_read_unlock();
1da177e4
LT		 3106 if (!task)
3107 goto out;
3108
444ceed8 3109 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 3110 put_task_struct(task);
1da177e4 3111out:
c52a47ac 3112 return ERR_PTR(result);
1da177e4
LT		 3113}
3114
1da177e4 3115/*
0804ef4b 3116 * Find the first task with tgid >= tgid
0bc58a91 3117 *
1da177e4 3118 */
19fd4bb2
EB		 3119struct tgid_iter {
3120 unsigned int tgid;
0804ef4b 3121 struct task_struct *task;
19fd4bb2
EB		 3122};
3123static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3124{
0804ef4b 3125 struct pid *pid;
1da177e4 3126
19fd4bb2
EB		 3127 if (iter.task)
3128 put_task_struct(iter.task);
454cc105 3129 rcu_read_lock();
0804ef4b 3130retry:
19fd4bb2
EB		 3131 iter.task = NULL;
3132 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 3133 if (pid) {
19fd4bb2
EB		 3134 iter.tgid = pid_nr_ns(pid, ns);
3135 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 3136 /* What we to know is if the pid we have find is the
3137 * pid of a thread_group_leader. Testing for task
3138 * being a thread_group_leader is the obvious thing
3139 * todo but there is a window when it fails, due to
3140 * the pid transfer logic in de_thread.
3141 *
3142 * So we perform the straight forward test of seeing
3143 * if the pid we have found is the pid of a thread
3144 * group leader, and don't worry if the task we have
3145 * found doesn't happen to be a thread group leader.
3146 * As we don't care in the case of readdir.
3147 */
19fd4bb2
EB		 3148 if (!iter.task || !has_group_leader_pid(iter.task)) {
3149 iter.tgid += 1;
0804ef4b 3150 goto retry;
19fd4bb2
EB		 3151 }
3152 get_task_struct(iter.task);
0bc58a91 3153 }
454cc105 3154 rcu_read_unlock();
19fd4bb2 3155 return iter;
1da177e4
LT		 3156}
3157
0097875b 3158#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
0804ef4b 3159
1da177e4 3160/* for the /proc/ directory itself, after non-process stuff has been done */
f0c3b509 3161int proc_pid_readdir(struct file *file, struct dir_context *ctx)
1da177e4 3162{
19fd4bb2 3163 struct tgid_iter iter;
3aa3377f 3164 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info;
f0c3b509 3165 loff_t pos = ctx->pos;
1da177e4 3166
021ada7d 3167 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
f0c3b509 3168 return 0;
1da177e4 3169
0097875b 3170 if (pos == TGID_OFFSET - 2) {
2b0143b5 3171 struct inode *inode = d_inode(ns->proc_self);
db963164 3172 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
f0c3b509 3173 return 0;
0097875b
EB		 3174 ctx->pos = pos = pos + 1;
3175 }
3176 if (pos == TGID_OFFSET - 1) {
2b0143b5 3177 struct inode *inode = d_inode(ns->proc_thread_self);
0097875b
EB		 3178 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3179 return 0;
3180 ctx->pos = pos = pos + 1;
021ada7d 3181 }
0097875b 3182 iter.tgid = pos - TGID_OFFSET;
19fd4bb2 3183 iter.task = NULL;
19fd4bb2
EB		 3184 for (iter = next_tgid(ns, iter);
3185 iter.task;
3186 iter.tgid += 1, iter = next_tgid(ns, iter)) {
f0c3b509
AV		 3187 char name[PROC_NUMBUF];
3188 int len;
3ba4bcee
ED		 3189
3190 cond_resched();
f0c3b509
AV		 3191 if (!has_pid_permissions(ns, iter.task, 2))
3192 continue;
0499680a 3193
f0c3b509
AV		 3194 len = snprintf(name, sizeof(name), "%d", iter.tgid);
3195 ctx->pos = iter.tgid + TGID_OFFSET;
3196 if (!proc_fill_cache(file, ctx, name, len,
3197 proc_pid_instantiate, iter.task, NULL)) {
19fd4bb2 3198 put_task_struct(iter.task);
f0c3b509 3199 return 0;
1da177e4 3200 }
0bc58a91 3201 }
f0c3b509 3202 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
0bc58a91
EB		 3203 return 0;
3204}
1da177e4 3205
1b3044e3
JD		 3206/*
3207 * proc_tid_comm_permission is a special permission function exclusively
3208 * used for the node /proc/<pid>/task/<tid>/comm.
3209 * It bypasses generic permission checks in the case where a task of the same
3210 * task group attempts to access the node.
3211 * The rationale behind this is that glibc and bionic access this node for
3212 * cross thread naming (pthread_set/getname_np(!self)). However, if
3213 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3214 * which locks out the cross thread naming implementation.
3215 * This function makes sure that the node is always accessible for members of
3216 * same thread group.
3217 */
3218static int proc_tid_comm_permission(struct inode *inode, int mask)
3219{
3220 bool is_same_tgroup;
3221 struct task_struct *task;
3222
3223 task = get_proc_task(inode);
3224 if (!task)
3225 return -ESRCH;
3226 is_same_tgroup = same_thread_group(current, task);
3227 put_task_struct(task);
3228
3229 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3230 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3231 * read or written by the members of the corresponding
3232 * thread group.
3233 */
3234 return 0;
3235 }
3236
3237 return generic_permission(inode, mask);
3238}
3239
3240static const struct inode_operations proc_tid_comm_inode_operations = {
3241 .permission = proc_tid_comm_permission,
3242};
3243
28a6d671
EB		 3244/*
3245 * Tasks
3246 */
c5141e6d 3247static const struct pid_entry tid_base_stuff[] = {
631f9c18 3248 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3249 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
6b4e306a 3250 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
6ba8ed79
EB		 3251#ifdef CONFIG_NET
3252 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3253#endif
631f9c18 3254 REG("environ", S_IRUSR, proc_environ_operations),
c5317167 3255 REG("auxv", S_IRUSR, proc_auxv_operations),
631f9c18 3256 ONE("status", S_IRUGO, proc_pid_status),
35a35046 3257 ONE("personality", S_IRUSR, proc_pid_personality),
1c963eb1 3258 ONE("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3259#ifdef CONFIG_SCHED_DEBUG
631f9c18 3260 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3261#endif
1b3044e3
JD		 3262 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3263 &proc_tid_comm_inode_operations,
3264 &proc_pid_set_comm_operations, {}),
ebcb6734 3265#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
09d93bd6 3266 ONE("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 3267#endif
c2c0bb44 3268 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
631f9c18
AD		 3269 ONE("stat", S_IRUGO, proc_tid_stat),
3270 ONE("statm", S_IRUGO, proc_pid_statm),
b7643757 3271 REG("maps", S_IRUGO, proc_tid_maps_operations),
2e13ba54 3272#ifdef CONFIG_PROC_CHILDREN
81841161
CG		 3273 REG("children", S_IRUGO, proc_tid_children_operations),
3274#endif
28a6d671 3275#ifdef CONFIG_NUMA
b7643757 3276 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
28a6d671 3277#endif
631f9c18
AD		 3278 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3279 LNK("cwd", proc_cwd_link),
3280 LNK("root", proc_root_link),
3281 LNK("exe", proc_exe_link),
3282 REG("mounts", S_IRUGO, proc_mounts_operations),
3283 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3284#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18 3285 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
b7643757 3286 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
32ed74a4 3287 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 3288#endif
3289#ifdef CONFIG_SECURITY
631f9c18 3290 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3291#endif
3292#ifdef CONFIG_KALLSYMS
edfcd606 3293 ONE("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3294#endif
2ec220e2 3295#ifdef CONFIG_STACKTRACE
35a35046 3296 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671 3297#endif
5968cece 3298#ifdef CONFIG_SCHED_INFO
f6e826ca 3299 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3300#endif
9745512c 3301#ifdef CONFIG_LATENCYTOP
631f9c18 3302 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3303#endif
8793d854 3304#ifdef CONFIG_PROC_PID_CPUSET
52de4779 3305 ONE("cpuset", S_IRUGO, proc_cpuset_show),
a424316c
PM		 3306#endif
3307#ifdef CONFIG_CGROUPS
006f4ac4 3308 ONE("cgroup", S_IRUGO, proc_cgroup_show),
28a6d671 3309#endif
6ba51e37 3310 ONE("oom_score", S_IRUGO, proc_oom_score),
fa0cbbf1 3311 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
a63d83f4 3312 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3313#ifdef CONFIG_AUDITSYSCALL
631f9c18 3314 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
26ec3c64 3315 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 3316#endif
f4f154fd 3317#ifdef CONFIG_FAULT_INJECTION
631f9c18 3318 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3319#endif
297c5d92 3320#ifdef CONFIG_TASK_IO_ACCOUNTING
19aadc98 3321 ONE("io", S_IRUSR, proc_tid_io_accounting),
297c5d92 3322#endif
f133ecca 3323#ifdef CONFIG_HARDWALL
d962c144 3324 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
f133ecca 3325#endif
22d917d8
EB		 3326#ifdef CONFIG_USER_NS
3327 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3328 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
f76d207a 3329 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
9cc46516 3330 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
22d917d8 3331#endif
28a6d671
EB		 3332};
3333
f0c3b509 3334static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
28a6d671 3335{
f0c3b509
AV		 3336 return proc_pident_readdir(file, ctx,
3337 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3338}
3339
00cd8dd3
AV		 3340static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3341{
7bcd6b0e
EB		 3342 return proc_pident_lookup(dir, dentry,
3343 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3344}
3345
00977a59 3346static const struct file_operations proc_tid_base_operations = {
28a6d671 3347 .read = generic_read_dir,
f50752ea
AV		 3348 .iterate_shared = proc_tid_base_readdir,
3349 .llseek = generic_file_llseek,
28a6d671
EB		 3350};
3351
c5ef1c42 3352static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3353 .lookup = proc_tid_base_lookup,
3354 .getattr = pid_getattr,
3355 .setattr = proc_setattr,
3356};
3357
c52a47ac 3358static int proc_task_instantiate(struct inode *dir,
c5141e6d 3359 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 3360{
444ceed8 3361 struct inode *inode;
db978da8 3362 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
444ceed8
EB		 3363
3364 if (!inode)
3365 goto out;
444ceed8
EB		 3366 inode->i_op = &proc_tid_base_inode_operations;
3367 inode->i_fop = &proc_tid_base_operations;
3368 inode->i_flags|=S_IMMUTABLE;
aed54175 3369
1270dd8d 3370 set_nlink(inode, nlink_tid);
444ceed8 3371
fb045adb 3372 d_set_d_op(dentry, &pid_dentry_operations);
444ceed8
EB		 3373
3374 d_add(dentry, inode);
3375 /* Close the race of the process dying before we return the dentry */
0b728e19 3376 if (pid_revalidate(dentry, 0))
c52a47ac 3377 return 0;
444ceed8 3378out:
c52a47ac 3379 return -ENOENT;
444ceed8
EB		 3380}
3381
00cd8dd3 3382static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
28a6d671 3383{
c52a47ac 3384 int result = -ENOENT;
28a6d671
EB		 3385 struct task_struct *task;
3386 struct task_struct *leader = get_proc_task(dir);
28a6d671 3387 unsigned tid;
b488893a 3388 struct pid_namespace *ns;
28a6d671
EB		 3389
3390 if (!leader)
3391 goto out_no_task;
3392
dbcdb504 3393 tid = name_to_int(&dentry->d_name);
28a6d671
EB		 3394 if (tid == ~0U)
3395 goto out;
3396
b488893a 3397 ns = dentry->d_sb->s_fs_info;
28a6d671 3398 rcu_read_lock();
b488893a 3399 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3400 if (task)
3401 get_task_struct(task);
3402 rcu_read_unlock();
3403 if (!task)
3404 goto out;
bac0abd6 3405 if (!same_thread_group(leader, task))
28a6d671
EB		 3406 goto out_drop_task;
3407
444ceed8 3408 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3409out_drop_task:
3410 put_task_struct(task);
3411out:
3412 put_task_struct(leader);
3413out_no_task:
c52a47ac 3414 return ERR_PTR(result);
28a6d671
EB		 3415}
3416
0bc58a91
EB		 3417/*
3418 * Find the first tid of a thread group to return to user space.
3419 *
3420 * Usually this is just the thread group leader, but if the users
3421 * buffer was too small or there was a seek into the middle of the
3422 * directory we have more work todo.
3423 *
3424 * In the case of a short read we start with find_task_by_pid.
3425 *
3426 * In the case of a seek we start with the leader and walk nr
3427 * threads past it.
3428 */
9f6e963f
ON		 3429static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3430 struct pid_namespace *ns)
0bc58a91 3431{
d855a4b7 3432 struct task_struct *pos, *task;
9f6e963f
ON		 3433 unsigned long nr = f_pos;
3434
3435 if (nr != f_pos) /* 32bit overflow? */
3436 return NULL;
1da177e4 3437
cc288738 3438 rcu_read_lock();
d855a4b7
ON		 3439 task = pid_task(pid, PIDTYPE_PID);
3440 if (!task)
3441 goto fail;
3442
3443 /* Attempt to start with the tid of a thread */
9f6e963f 3444 if (tid && nr) {
b488893a 3445 pos = find_task_by_pid_ns(tid, ns);
d855a4b7 3446 if (pos && same_thread_group(pos, task))
a872ff0c 3447 goto found;
0bc58a91 3448 }
1da177e4 3449
0bc58a91 3450 /* If nr exceeds the number of threads there is nothing todo */
9f6e963f 3451 if (nr >= get_nr_threads(task))
c986c14a 3452 goto fail;
1da177e4 3453
a872ff0c
ON		 3454 /* If we haven't found our starting place yet start
3455 * with the leader and walk nr threads forward.
0bc58a91 3456 */
d855a4b7 3457 pos = task = task->group_leader;
c986c14a 3458 do {
9f6e963f 3459 if (!nr--)
c986c14a 3460 goto found;
d855a4b7 3461 } while_each_thread(task, pos);
c986c14a
ON		 3462fail:
3463 pos = NULL;
3464 goto out;
a872ff0c
ON		 3465found:
3466 get_task_struct(pos);
3467out:
cc288738 3468 rcu_read_unlock();
0bc58a91
EB		 3469 return pos;
3470}
3471
3472/*
3473 * Find the next thread in the thread list.
3474 * Return NULL if there is an error or no next thread.
3475 *
3476 * The reference to the input task_struct is released.
3477 */
3478static struct task_struct *next_tid(struct task_struct *start)
3479{
c1df7fb8 3480 struct task_struct *pos = NULL;
cc288738 3481 rcu_read_lock();
c1df7fb8 3482 if (pid_alive(start)) {
0bc58a91 3483 pos = next_thread(start);
c1df7fb8
ON		 3484 if (thread_group_leader(pos))
3485 pos = NULL;
3486 else
3487 get_task_struct(pos);
3488 }
cc288738 3489 rcu_read_unlock();
0bc58a91
EB		 3490 put_task_struct(start);
3491 return pos;
1da177e4
LT		 3492}
3493
3494/* for the /proc/TGID/task/ directories */
f0c3b509 3495static int proc_task_readdir(struct file *file, struct dir_context *ctx)
1da177e4 3496{
d855a4b7
ON		 3497 struct inode *inode = file_inode(file);
3498 struct task_struct *task;
b488893a 3499 struct pid_namespace *ns;
f0c3b509 3500 int tid;
1da177e4 3501
d855a4b7 3502 if (proc_inode_is_dead(inode))
f0c3b509 3503 return -ENOENT;
1da177e4 3504
f0c3b509 3505 if (!dir_emit_dots(file, ctx))
d855a4b7 3506 return 0;
1da177e4 3507
0bc58a91
EB		 3508 /* f_version caches the tgid value that the last readdir call couldn't
3509 * return. lseek aka telldir automagically resets f_version to 0.
3510 */
3aa3377f 3511 ns = inode->i_sb->s_fs_info;
f0c3b509
AV		 3512 tid = (int)file->f_version;
3513 file->f_version = 0;
d855a4b7 3514 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
0bc58a91 3515 task;
f0c3b509
AV		 3516 task = next_tid(task), ctx->pos++) {
3517 char name[PROC_NUMBUF];
3518 int len;
b488893a 3519 tid = task_pid_nr_ns(task, ns);
f0c3b509
AV		 3520 len = snprintf(name, sizeof(name), "%d", tid);
3521 if (!proc_fill_cache(file, ctx, name, len,
3522 proc_task_instantiate, task, NULL)) {
0bc58a91
EB		 3523 /* returning this tgid failed, save it as the first
3524 * pid for the next readir call */
f0c3b509 3525 file->f_version = (u64)tid;
0bc58a91 3526 put_task_struct(task);
1da177e4 3527 break;
0bc58a91 3528 }
1da177e4 3529 }
d855a4b7 3530
f0c3b509 3531 return 0;
1da177e4 3532}
6e66b52b
EB		 3533
3534static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3535{
2b0143b5 3536 struct inode *inode = d_inode(dentry);
99f89551 3537 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3538 generic_fillattr(inode, stat);
3539
99f89551 3540 if (p) {
99f89551 3541 stat->nlink += get_nr_threads(p);
99f89551 3542 put_task_struct(p);
6e66b52b
EB		 3543 }
3544
3545 return 0;
3546}
28a6d671 3547
c5ef1c42 3548static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3549 .lookup = proc_task_lookup,
3550 .getattr = proc_task_getattr,
3551 .setattr = proc_setattr,
0499680a 3552 .permission = proc_pid_permission,
28a6d671
EB		 3553};
3554
00977a59 3555static const struct file_operations proc_task_operations = {
28a6d671 3556 .read = generic_read_dir,
f50752ea
AV		 3557 .iterate_shared = proc_task_readdir,
3558 .llseek = generic_file_llseek,
28a6d671 3559};
1270dd8d
AD		 3560
3561void __init set_proc_pid_nlink(void)
3562{
3563 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3564 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3565}
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