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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / fs / proc / base.c
blob9298324325ed88f715f23470f4c6ff3f091e17b0
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/proc/base.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 *
7 * proc base directory handling functions
8 *
9 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
10 * Instead of using magical inumbers to determine the kind of object
11 * we allocate and fill in-core inodes upon lookup. They don't even
12 * go into icache. We cache the reference to task_struct upon lookup too.
13 * Eventually it should become a filesystem in its own. We don't use the
14 * rest of procfs anymore.
15 *
16 *
17 * Changelog:
18 * 17-Jan-2005
19 * Allan Bezerra
20 * Bruna Moreira <bruna.moreira@indt.org.br>
21 * Edjard Mota <edjard.mota@indt.org.br>
22 * Ilias Biris <ilias.biris@indt.org.br>
23 * Mauricio Lin <mauricio.lin@indt.org.br>
24 *
25 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
26 *
27 * A new process specific entry (smaps) included in /proc. It shows the
28 * size of rss for each memory area. The maps entry lacks information
29 * about physical memory size (rss) for each mapped file, i.e.,
30 * rss information for executables and library files.
31 * This additional information is useful for any tools that need to know
32 * about physical memory consumption for a process specific library.
33 *
34 * Changelog:
35 * 21-Feb-2005
36 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
37 * Pud inclusion in the page table walking.
38 *
39 * ChangeLog:
40 * 10-Mar-2005
41 * 10LE Instituto Nokia de Tecnologia - INdT:
42 * A better way to walks through the page table as suggested by Hugh Dickins.
43 *
44 * Simo Piiroinen <simo.piiroinen@nokia.com>:
45 * Smaps information related to shared, private, clean and dirty pages.
46 *
47 * Paul Mundt <paul.mundt@nokia.com>:
48 * Overall revision about smaps.
49 */
50
51 #include <linux/uaccess.h>
52
53 #include <linux/errno.h>
54 #include <linux/time.h>
55 #include <linux/proc_fs.h>
56 #include <linux/stat.h>
57 #include <linux/task_io_accounting_ops.h>
58 #include <linux/init.h>
59 #include <linux/capability.h>
60 #include <linux/file.h>
61 #include <linux/fdtable.h>
62 #include <linux/string.h>
63 #include <linux/seq_file.h>
64 #include <linux/namei.h>
65 #include <linux/mnt_namespace.h>
66 #include <linux/mm.h>
67 #include <linux/swap.h>
68 #include <linux/rcupdate.h>
69 #include <linux/kallsyms.h>
70 #include <linux/stacktrace.h>
71 #include <linux/resource.h>
72 #include <linux/module.h>
73 #include <linux/mount.h>
74 #include <linux/security.h>
75 #include <linux/ptrace.h>
76 #include <linux/tracehook.h>
77 #include <linux/printk.h>
78 #include <linux/cache.h>
79 #include <linux/cgroup.h>
80 #include <linux/cpuset.h>
81 #include <linux/audit.h>
82 #include <linux/poll.h>
83 #include <linux/nsproxy.h>
84 #include <linux/oom.h>
85 #include <linux/elf.h>
86 #include <linux/pid_namespace.h>
87 #include <linux/user_namespace.h>
88 #include <linux/fs_struct.h>
89 #include <linux/slab.h>
90 #include <linux/sched/autogroup.h>
91 #include <linux/sched/mm.h>
92 #include <linux/sched/coredump.h>
93 #include <linux/sched/debug.h>
94 #include <linux/sched/stat.h>
95 #include <linux/flex_array.h>
96 #include <linux/posix-timers.h>
97 #ifdef CONFIG_HARDWALL
98 #include <asm/hardwall.h>
99 #endif
100 #include <trace/events/oom.h>
101 #include "internal.h"
102 #include "fd.h"
103
104 #include "../../lib/kstrtox.h"
105
106 /* NOTE:
107 * Implementing inode permission operations in /proc is almost
108 * certainly an error. Permission checks need to happen during
109 * each system call not at open time. The reason is that most of
110 * what we wish to check for permissions in /proc varies at runtime.
111 *
112 * The classic example of a problem is opening file descriptors
113 * in /proc for a task before it execs a suid executable.
114 */
115
116 static u8 nlink_tid __ro_after_init;
117 static u8 nlink_tgid __ro_after_init;
118
119 struct pid_entry {
120 const char *name;
121 unsigned int len;
122 umode_t mode;
123 const struct inode_operations *iop;
124 const struct file_operations *fop;
125 union proc_op op;
126 };
127
128 #define NOD(NAME, MODE, IOP, FOP, OP) { \
129 .name = (NAME), \
130 .len = sizeof(NAME) - 1, \
131 .mode = MODE, \
132 .iop = IOP, \
133 .fop = FOP, \
134 .op = OP, \
135 }
136
137 #define DIR(NAME, MODE, iops, fops) \
138 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
139 #define LNK(NAME, get_link) \
140 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
141 &proc_pid_link_inode_operations, NULL, \
142 { .proc_get_link = get_link } )
143 #define REG(NAME, MODE, fops) \
144 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
145 #define ONE(NAME, MODE, show) \
146 NOD(NAME, (S_IFREG|(MODE)), \
147 NULL, &proc_single_file_operations, \
148 { .proc_show = show } )
149
150 /*
151 * Count the number of hardlinks for the pid_entry table, excluding the .
152 * and .. links.
153 */
154 static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,
155 unsigned int n)
156 {
157 unsigned int i;
158 unsigned int count;
159
160 count = 2;
161 for (i = 0; i < n; ++i) {
162 if (S_ISDIR(entries[i].mode))
163 ++count;
164 }
165
166 return count;
167 }
168
169 static int get_task_root(struct task_struct *task, struct path *root)
170 {
171 int result = -ENOENT;
172
173 task_lock(task);
174 if (task->fs) {
175 get_fs_root(task->fs, root);
176 result = 0;
177 }
178 task_unlock(task);
179 return result;
180 }
181
182 static int proc_cwd_link(struct dentry *dentry, struct path *path)
183 {
184 struct task_struct *task = get_proc_task(d_inode(dentry));
185 int result = -ENOENT;
186
187 if (task) {
188 task_lock(task);
189 if (task->fs) {
190 get_fs_pwd(task->fs, path);
191 result = 0;
192 }
193 task_unlock(task);
194 put_task_struct(task);
195 }
196 return result;
197 }
198
199 static int proc_root_link(struct dentry *dentry, struct path *path)
200 {
201 struct task_struct *task = get_proc_task(d_inode(dentry));
202 int result = -ENOENT;
203
204 if (task) {
205 result = get_task_root(task, path);
206 put_task_struct(task);
207 }
208 return result;
209 }
210
211 static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
212 size_t _count, loff_t *pos)
213 {
214 struct task_struct *tsk;
215 struct mm_struct *mm;
216 char *page;
217 unsigned long count = _count;
218 unsigned long arg_start, arg_end, env_start, env_end;
219 unsigned long len1, len2, len;
220 unsigned long p;
221 char c;
222 ssize_t rv;
223
224 BUG_ON(*pos < 0);
225
226 tsk = get_proc_task(file_inode(file));
227 if (!tsk)
228 return -ESRCH;
229 mm = get_task_mm(tsk);
230 put_task_struct(tsk);
231 if (!mm)
232 return 0;
233 /* Check if process spawned far enough to have cmdline. */
234 if (!mm->env_end) {
235 rv = 0;
236 goto out_mmput;
237 }
238
239 page = (char *)__get_free_page(GFP_KERNEL);
240 if (!page) {
241 rv = -ENOMEM;
242 goto out_mmput;
243 }
244
245 down_read(&mm->mmap_sem);
246 arg_start = mm->arg_start;
247 arg_end = mm->arg_end;
248 env_start = mm->env_start;
249 env_end = mm->env_end;
250 up_read(&mm->mmap_sem);
251
252 BUG_ON(arg_start > arg_end);
253 BUG_ON(env_start > env_end);
254
255 len1 = arg_end - arg_start;
256 len2 = env_end - env_start;
257
258 /* Empty ARGV. */
259 if (len1 == 0) {
260 rv = 0;
261 goto out_free_page;
262 }
263 /*
264 * Inherently racy -- command line shares address space
265 * with code and data.
266 */
267 rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0);
268 if (rv <= 0)
269 goto out_free_page;
270
271 rv = 0;
272
273 if (c == '\0') {
274 /* Command line (set of strings) occupies whole ARGV. */
275 if (len1 <= *pos)
276 goto out_free_page;
277
278 p = arg_start + *pos;
279 len = len1 - *pos;
280 while (count > 0 && len > 0) {
281 unsigned int _count;
282 int nr_read;
283
284 _count = min3(count, len, PAGE_SIZE);
285 nr_read = access_remote_vm(mm, p, page, _count, 0);
286 if (nr_read < 0)
287 rv = nr_read;
288 if (nr_read <= 0)
289 goto out_free_page;
290
291 if (copy_to_user(buf, page, nr_read)) {
292 rv = -EFAULT;
293 goto out_free_page;
294 }
295
296 p += nr_read;
297 len -= nr_read;
298 buf += nr_read;
299 count -= nr_read;
300 rv += nr_read;
301 }
302 } else {
303 /*
304 * Command line (1 string) occupies ARGV and
305 * extends into ENVP.
306 */
307 struct {
308 unsigned long p;
309 unsigned long len;
310 } cmdline[2] = {
311 { .p = arg_start, .len = len1 },
312 { .p = env_start, .len = len2 },
313 };
314 loff_t pos1 = *pos;
315 unsigned int i;
316
317 i = 0;
318 while (i < 2 && pos1 >= cmdline[i].len) {
319 pos1 -= cmdline[i].len;
320 i++;
321 }
322 while (i < 2) {
323 p = cmdline[i].p + pos1;
324 len = cmdline[i].len - pos1;
325 while (count > 0 && len > 0) {
326 unsigned int _count, l;
327 int nr_read;
328 bool final;
329
330 _count = min3(count, len, PAGE_SIZE);
331 nr_read = access_remote_vm(mm, p, page, _count, 0);
332 if (nr_read < 0)
333 rv = nr_read;
334 if (nr_read <= 0)
335 goto out_free_page;
336
337 /*
338 * Command line can be shorter than whole ARGV
339 * even if last "marker" byte says it is not.
340 */
341 final = false;
342 l = strnlen(page, nr_read);
343 if (l < nr_read) {
344 nr_read = l;
345 final = true;
346 }
347
348 if (copy_to_user(buf, page, nr_read)) {
349 rv = -EFAULT;
350 goto out_free_page;
351 }
352
353 p += nr_read;
354 len -= nr_read;
355 buf += nr_read;
356 count -= nr_read;
357 rv += nr_read;
358
359 if (final)
360 goto out_free_page;
361 }
362
363 /* Only first chunk can be read partially. */
364 pos1 = 0;
365 i++;
366 }
367 }
368
369 out_free_page:
370 free_page((unsigned long)page);
371 out_mmput:
372 mmput(mm);
373 if (rv > 0)
374 *pos += rv;
375 return rv;
376 }
377
378 static const struct file_operations proc_pid_cmdline_ops = {
379 .read = proc_pid_cmdline_read,
380 .llseek = generic_file_llseek,
381 };
382
383 #ifdef CONFIG_KALLSYMS
384 /*
385 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
386 * Returns the resolved symbol. If that fails, simply return the address.
387 */
388 static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
389 struct pid *pid, struct task_struct *task)
390 {
391 unsigned long wchan;
392 char symname[KSYM_NAME_LEN];
393
394 wchan = get_wchan(task);
395
396 if (wchan && ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)
397 && !lookup_symbol_name(wchan, symname))
398 seq_printf(m, "%s", symname);
399 else
400 seq_putc(m, '0');
401
402 return 0;
403 }
404 #endif /* CONFIG_KALLSYMS */
405
406 static int lock_trace(struct task_struct *task)
407 {
408 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
409 if (err)
410 return err;
411 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
412 mutex_unlock(&task->signal->cred_guard_mutex);
413 return -EPERM;
414 }
415 return 0;
416 }
417
418 static void unlock_trace(struct task_struct *task)
419 {
420 mutex_unlock(&task->signal->cred_guard_mutex);
421 }
422
423 #ifdef CONFIG_STACKTRACE
424
425 #define MAX_STACK_TRACE_DEPTH 64
426
427 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
428 struct pid *pid, struct task_struct *task)
429 {
430 struct stack_trace trace;
431 unsigned long *entries;
432 int err;
433 int i;
434
435 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
436 if (!entries)
437 return -ENOMEM;
438
439 trace.nr_entries = 0;
440 trace.max_entries = MAX_STACK_TRACE_DEPTH;
441 trace.entries = entries;
442 trace.skip = 0;
443
444 err = lock_trace(task);
445 if (!err) {
446 save_stack_trace_tsk(task, &trace);
447
448 for (i = 0; i < trace.nr_entries; i++) {
449 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]);
450 }
451 unlock_trace(task);
452 }
453 kfree(entries);
454
455 return err;
456 }
457 #endif
458
459 #ifdef CONFIG_SCHED_INFO
460 /*
461 * Provides /proc/PID/schedstat
462 */
463 static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
464 struct pid *pid, struct task_struct *task)
465 {
466 if (unlikely(!sched_info_on()))
467 seq_printf(m, "0 0 0\n");
468 else
469 seq_printf(m, "%llu %llu %lu\n",
470 (unsigned long long)task->se.sum_exec_runtime,
471 (unsigned long long)task->sched_info.run_delay,
472 task->sched_info.pcount);
473
474 return 0;
475 }
476 #endif
477
478 #ifdef CONFIG_LATENCYTOP
479 static int lstats_show_proc(struct seq_file *m, void *v)
480 {
481 int i;
482 struct inode *inode = m->private;
483 struct task_struct *task = get_proc_task(inode);
484
485 if (!task)
486 return -ESRCH;
487 seq_puts(m, "Latency Top version : v0.1\n");
488 for (i = 0; i < 32; i++) {
489 struct latency_record *lr = &task->latency_record[i];
490 if (lr->backtrace[0]) {
491 int q;
492 seq_printf(m, "%i %li %li",
493 lr->count, lr->time, lr->max);
494 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
495 unsigned long bt = lr->backtrace[q];
496 if (!bt)
497 break;
498 if (bt == ULONG_MAX)
499 break;
500 seq_printf(m, " %ps", (void *)bt);
501 }
502 seq_putc(m, '\n');
503 }
504
505 }
506 put_task_struct(task);
507 return 0;
508 }
509
510 static int lstats_open(struct inode *inode, struct file *file)
511 {
512 return single_open(file, lstats_show_proc, inode);
513 }
514
515 static ssize_t lstats_write(struct file *file, const char __user *buf,
516 size_t count, loff_t *offs)
517 {
518 struct task_struct *task = get_proc_task(file_inode(file));
519
520 if (!task)
521 return -ESRCH;
522 clear_all_latency_tracing(task);
523 put_task_struct(task);
524
525 return count;
526 }
527
528 static const struct file_operations proc_lstats_operations = {
529 .open = lstats_open,
530 .read = seq_read,
531 .write = lstats_write,
532 .llseek = seq_lseek,
533 .release = single_release,
534 };
535
536 #endif
537
538 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
539 struct pid *pid, struct task_struct *task)
540 {
541 unsigned long totalpages = totalram_pages + total_swap_pages;
542 unsigned long points = 0;
543
544 points = oom_badness(task, NULL, NULL, totalpages) *
545 1000 / totalpages;
546 seq_printf(m, "%lu\n", points);
547
548 return 0;
549 }
550
551 struct limit_names {
552 const char *name;
553 const char *unit;
554 };
555
556 static const struct limit_names lnames[RLIM_NLIMITS] = {
557 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
558 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
559 [RLIMIT_DATA] = {"Max data size", "bytes"},
560 [RLIMIT_STACK] = {"Max stack size", "bytes"},
561 [RLIMIT_CORE] = {"Max core file size", "bytes"},
562 [RLIMIT_RSS] = {"Max resident set", "bytes"},
563 [RLIMIT_NPROC] = {"Max processes", "processes"},
564 [RLIMIT_NOFILE] = {"Max open files", "files"},
565 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
566 [RLIMIT_AS] = {"Max address space", "bytes"},
567 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
568 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
569 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
570 [RLIMIT_NICE] = {"Max nice priority", NULL},
571 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
572 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
573 };
574
575 /* Display limits for a process */
576 static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
577 struct pid *pid, struct task_struct *task)
578 {
579 unsigned int i;
580 unsigned long flags;
581
582 struct rlimit rlim[RLIM_NLIMITS];
583
584 if (!lock_task_sighand(task, &flags))
585 return 0;
586 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
587 unlock_task_sighand(task, &flags);
588
589 /*
590 * print the file header
591 */
592 seq_printf(m, "%-25s %-20s %-20s %-10s\n",
593 "Limit", "Soft Limit", "Hard Limit", "Units");
594
595 for (i = 0; i < RLIM_NLIMITS; i++) {
596 if (rlim[i].rlim_cur == RLIM_INFINITY)
597 seq_printf(m, "%-25s %-20s ",
598 lnames[i].name, "unlimited");
599 else
600 seq_printf(m, "%-25s %-20lu ",
601 lnames[i].name, rlim[i].rlim_cur);
602
603 if (rlim[i].rlim_max == RLIM_INFINITY)
604 seq_printf(m, "%-20s ", "unlimited");
605 else
606 seq_printf(m, "%-20lu ", rlim[i].rlim_max);
607
608 if (lnames[i].unit)
609 seq_printf(m, "%-10s\n", lnames[i].unit);
610 else
611 seq_putc(m, '\n');
612 }
613
614 return 0;
615 }
616
617 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
618 static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
619 struct pid *pid, struct task_struct *task)
620 {
621 long nr;
622 unsigned long args[6], sp, pc;
623 int res;
624
625 res = lock_trace(task);
626 if (res)
627 return res;
628
629 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
630 seq_puts(m, "running\n");
631 else if (nr < 0)
632 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
633 else
634 seq_printf(m,
635 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
636 nr,
637 args[0], args[1], args[2], args[3], args[4], args[5],
638 sp, pc);
639 unlock_trace(task);
640
641 return 0;
642 }
643 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
644
645 /************************************************************************/
646 /* Here the fs part begins */
647 /************************************************************************/
648
649 /* permission checks */
650 static int proc_fd_access_allowed(struct inode *inode)
651 {
652 struct task_struct *task;
653 int allowed = 0;
654 /* Allow access to a task's file descriptors if it is us or we
655 * may use ptrace attach to the process and find out that
656 * information.
657 */
658 task = get_proc_task(inode);
659 if (task) {
660 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
661 put_task_struct(task);
662 }
663 return allowed;
664 }
665
666 int proc_setattr(struct dentry *dentry, struct iattr *attr)
667 {
668 int error;
669 struct inode *inode = d_inode(dentry);
670
671 if (attr->ia_valid & ATTR_MODE)
672 return -EPERM;
673
674 error = setattr_prepare(dentry, attr);
675 if (error)
676 return error;
677
678 setattr_copy(inode, attr);
679 mark_inode_dirty(inode);
680 return 0;
681 }
682
683 /*
684 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
685 * or euid/egid (for hide_pid_min=2)?
686 */
687 static bool has_pid_permissions(struct pid_namespace *pid,
688 struct task_struct *task,
689 int hide_pid_min)
690 {
691 if (pid->hide_pid < hide_pid_min)
692 return true;
693 if (in_group_p(pid->pid_gid))
694 return true;
695 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
696 }
697
698
699 static int proc_pid_permission(struct inode *inode, int mask)
700 {
701 struct pid_namespace *pid = inode->i_sb->s_fs_info;
702 struct task_struct *task;
703 bool has_perms;
704
705 task = get_proc_task(inode);
706 if (!task)
707 return -ESRCH;
708 has_perms = has_pid_permissions(pid, task, HIDEPID_NO_ACCESS);
709 put_task_struct(task);
710
711 if (!has_perms) {
712 if (pid->hide_pid == HIDEPID_INVISIBLE) {
713 /*
714 * Let's make getdents(), stat(), and open()
715 * consistent with each other. If a process
716 * may not stat() a file, it shouldn't be seen
717 * in procfs at all.
718 */
719 return -ENOENT;
720 }
721
722 return -EPERM;
723 }
724 return generic_permission(inode, mask);
725 }
726
727
728
729 static const struct inode_operations proc_def_inode_operations = {
730 .setattr = proc_setattr,
731 };
732
733 static int proc_single_show(struct seq_file *m, void *v)
734 {
735 struct inode *inode = m->private;
736 struct pid_namespace *ns;
737 struct pid *pid;
738 struct task_struct *task;
739 int ret;
740
741 ns = inode->i_sb->s_fs_info;
742 pid = proc_pid(inode);
743 task = get_pid_task(pid, PIDTYPE_PID);
744 if (!task)
745 return -ESRCH;
746
747 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
748
749 put_task_struct(task);
750 return ret;
751 }
752
753 static int proc_single_open(struct inode *inode, struct file *filp)
754 {
755 return single_open(filp, proc_single_show, inode);
756 }
757
758 static const struct file_operations proc_single_file_operations = {
759 .open = proc_single_open,
760 .read = seq_read,
761 .llseek = seq_lseek,
762 .release = single_release,
763 };
764
765
766 struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
767 {
768 struct task_struct *task = get_proc_task(inode);
769 struct mm_struct *mm = ERR_PTR(-ESRCH);
770
771 if (task) {
772 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
773 put_task_struct(task);
774
775 if (!IS_ERR_OR_NULL(mm)) {
776 /* ensure this mm_struct can't be freed */
777 mmgrab(mm);
778 /* but do not pin its memory */
779 mmput(mm);
780 }
781 }
782
783 return mm;
784 }
785
786 static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
787 {
788 struct mm_struct *mm = proc_mem_open(inode, mode);
789
790 if (IS_ERR(mm))
791 return PTR_ERR(mm);
792
793 file->private_data = mm;
794 return 0;
795 }
796
797 static int mem_open(struct inode *inode, struct file *file)
798 {
799 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
800
801 /* OK to pass negative loff_t, we can catch out-of-range */
802 file->f_mode |= FMODE_UNSIGNED_OFFSET;
803
804 return ret;
805 }
806
807 static ssize_t mem_rw(struct file *file, char __user *buf,
808 size_t count, loff_t *ppos, int write)
809 {
810 struct mm_struct *mm = file->private_data;
811 unsigned long addr = *ppos;
812 ssize_t copied;
813 char *page;
814 unsigned int flags;
815
816 if (!mm)
817 return 0;
818
819 page = (char *)__get_free_page(GFP_KERNEL);
820 if (!page)
821 return -ENOMEM;
822
823 copied = 0;
824 if (!mmget_not_zero(mm))
825 goto free;
826
827 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0);
828
829 while (count > 0) {
830 int this_len = min_t(int, count, PAGE_SIZE);
831
832 if (write && copy_from_user(page, buf, this_len)) {
833 copied = -EFAULT;
834 break;
835 }
836
837 this_len = access_remote_vm(mm, addr, page, this_len, flags);
838 if (!this_len) {
839 if (!copied)
840 copied = -EIO;
841 break;
842 }
843
844 if (!write && copy_to_user(buf, page, this_len)) {
845 copied = -EFAULT;
846 break;
847 }
848
849 buf += this_len;
850 addr += this_len;
851 copied += this_len;
852 count -= this_len;
853 }
854 *ppos = addr;
855
856 mmput(mm);
857 free:
858 free_page((unsigned long) page);
859 return copied;
860 }
861
862 static ssize_t mem_read(struct file *file, char __user *buf,
863 size_t count, loff_t *ppos)
864 {
865 return mem_rw(file, buf, count, ppos, 0);
866 }
867
868 static ssize_t mem_write(struct file *file, const char __user *buf,
869 size_t count, loff_t *ppos)
870 {
871 return mem_rw(file, (char __user*)buf, count, ppos, 1);
872 }
873
874 loff_t mem_lseek(struct file *file, loff_t offset, int orig)
875 {
876 switch (orig) {
877 case 0:
878 file->f_pos = offset;
879 break;
880 case 1:
881 file->f_pos += offset;
882 break;
883 default:
884 return -EINVAL;
885 }
886 force_successful_syscall_return();
887 return file->f_pos;
888 }
889
890 static int mem_release(struct inode *inode, struct file *file)
891 {
892 struct mm_struct *mm = file->private_data;
893 if (mm)
894 mmdrop(mm);
895 return 0;
896 }
897
898 static const struct file_operations proc_mem_operations = {
899 .llseek = mem_lseek,
900 .read = mem_read,
901 .write = mem_write,
902 .open = mem_open,
903 .release = mem_release,
904 };
905
906 static int environ_open(struct inode *inode, struct file *file)
907 {
908 return __mem_open(inode, file, PTRACE_MODE_READ);
909 }
910
911 static ssize_t environ_read(struct file *file, char __user *buf,
912 size_t count, loff_t *ppos)
913 {
914 char *page;
915 unsigned long src = *ppos;
916 int ret = 0;
917 struct mm_struct *mm = file->private_data;
918 unsigned long env_start, env_end;
919
920 /* Ensure the process spawned far enough to have an environment. */
921 if (!mm || !mm->env_end)
922 return 0;
923
924 page = (char *)__get_free_page(GFP_KERNEL);
925 if (!page)
926 return -ENOMEM;
927
928 ret = 0;
929 if (!mmget_not_zero(mm))
930 goto free;
931
932 down_read(&mm->mmap_sem);
933 env_start = mm->env_start;
934 env_end = mm->env_end;
935 up_read(&mm->mmap_sem);
936
937 while (count > 0) {
938 size_t this_len, max_len;
939 int retval;
940
941 if (src >= (env_end - env_start))
942 break;
943
944 this_len = env_end - (env_start + src);
945
946 max_len = min_t(size_t, PAGE_SIZE, count);
947 this_len = min(max_len, this_len);
948
949 retval = access_remote_vm(mm, (env_start + src), page, this_len, 0);
950
951 if (retval <= 0) {
952 ret = retval;
953 break;
954 }
955
956 if (copy_to_user(buf, page, retval)) {
957 ret = -EFAULT;
958 break;
959 }
960
961 ret += retval;
962 src += retval;
963 buf += retval;
964 count -= retval;
965 }
966 *ppos = src;
967 mmput(mm);
968
969 free:
970 free_page((unsigned long) page);
971 return ret;
972 }
973
974 static const struct file_operations proc_environ_operations = {
975 .open = environ_open,
976 .read = environ_read,
977 .llseek = generic_file_llseek,
978 .release = mem_release,
979 };
980
981 static int auxv_open(struct inode *inode, struct file *file)
982 {
983 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
984 }
985
986 static ssize_t auxv_read(struct file *file, char __user *buf,
987 size_t count, loff_t *ppos)
988 {
989 struct mm_struct *mm = file->private_data;
990 unsigned int nwords = 0;
991
992 if (!mm)
993 return 0;
994 do {
995 nwords += 2;
996 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
997 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,
998 nwords * sizeof(mm->saved_auxv[0]));
999 }
1000
1001 static const struct file_operations proc_auxv_operations = {
1002 .open = auxv_open,
1003 .read = auxv_read,
1004 .llseek = generic_file_llseek,
1005 .release = mem_release,
1006 };
1007
1008 static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1009 loff_t *ppos)
1010 {
1011 struct task_struct *task = get_proc_task(file_inode(file));
1012 char buffer[PROC_NUMBUF];
1013 int oom_adj = OOM_ADJUST_MIN;
1014 size_t len;
1015
1016 if (!task)
1017 return -ESRCH;
1018 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1019 oom_adj = OOM_ADJUST_MAX;
1020 else
1021 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1022 OOM_SCORE_ADJ_MAX;
1023 put_task_struct(task);
1024 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1025 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1026 }
1027
1028 static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
1029 {
1030 static DEFINE_MUTEX(oom_adj_mutex);
1031 struct mm_struct *mm = NULL;
1032 struct task_struct *task;
1033 int err = 0;
1034
1035 task = get_proc_task(file_inode(file));
1036 if (!task)
1037 return -ESRCH;
1038
1039 mutex_lock(&oom_adj_mutex);
1040 if (legacy) {
1041 if (oom_adj < task->signal->oom_score_adj &&
1042 !capable(CAP_SYS_RESOURCE)) {
1043 err = -EACCES;
1044 goto err_unlock;
1045 }
1046 /*
1047 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1048 * /proc/pid/oom_score_adj instead.
1049 */
1050 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1051 current->comm, task_pid_nr(current), task_pid_nr(task),
1052 task_pid_nr(task));
1053 } else {
1054 if ((short)oom_adj < task->signal->oom_score_adj_min &&
1055 !capable(CAP_SYS_RESOURCE)) {
1056 err = -EACCES;
1057 goto err_unlock;
1058 }
1059 }
1060
1061 /*
1062 * Make sure we will check other processes sharing the mm if this is
1063 * not vfrok which wants its own oom_score_adj.
1064 * pin the mm so it doesn't go away and get reused after task_unlock
1065 */
1066 if (!task->vfork_done) {
1067 struct task_struct *p = find_lock_task_mm(task);
1068
1069 if (p) {
1070 if (atomic_read(&p->mm->mm_users) > 1) {
1071 mm = p->mm;
1072 mmgrab(mm);
1073 }
1074 task_unlock(p);
1075 }
1076 }
1077
1078 task->signal->oom_score_adj = oom_adj;
1079 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1080 task->signal->oom_score_adj_min = (short)oom_adj;
1081 trace_oom_score_adj_update(task);
1082
1083 if (mm) {
1084 struct task_struct *p;
1085
1086 rcu_read_lock();
1087 for_each_process(p) {
1088 if (same_thread_group(task, p))
1089 continue;
1090
1091 /* do not touch kernel threads or the global init */
1092 if (p->flags & PF_KTHREAD || is_global_init(p))
1093 continue;
1094
1095 task_lock(p);
1096 if (!p->vfork_done && process_shares_mm(p, mm)) {
1097 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",
1098 task_pid_nr(p), p->comm,
1099 p->signal->oom_score_adj, oom_adj,
1100 task_pid_nr(task), task->comm);
1101 p->signal->oom_score_adj = oom_adj;
1102 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1103 p->signal->oom_score_adj_min = (short)oom_adj;
1104 }
1105 task_unlock(p);
1106 }
1107 rcu_read_unlock();
1108 mmdrop(mm);
1109 }
1110 err_unlock:
1111 mutex_unlock(&oom_adj_mutex);
1112 put_task_struct(task);
1113 return err;
1114 }
1115
1116 /*
1117 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1118 * kernels. The effective policy is defined by oom_score_adj, which has a
1119 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1120 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1121 * Processes that become oom disabled via oom_adj will still be oom disabled
1122 * with this implementation.
1123 *
1124 * oom_adj cannot be removed since existing userspace binaries use it.
1125 */
1126 static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1127 size_t count, loff_t *ppos)
1128 {
1129 char buffer[PROC_NUMBUF];
1130 int oom_adj;
1131 int err;
1132
1133 memset(buffer, 0, sizeof(buffer));
1134 if (count > sizeof(buffer) - 1)
1135 count = sizeof(buffer) - 1;
1136 if (copy_from_user(buffer, buf, count)) {
1137 err = -EFAULT;
1138 goto out;
1139 }
1140
1141 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1142 if (err)
1143 goto out;
1144 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1145 oom_adj != OOM_DISABLE) {
1146 err = -EINVAL;
1147 goto out;
1148 }
1149
1150 /*
1151 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1152 * value is always attainable.
1153 */
1154 if (oom_adj == OOM_ADJUST_MAX)
1155 oom_adj = OOM_SCORE_ADJ_MAX;
1156 else
1157 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1158
1159 err = __set_oom_adj(file, oom_adj, true);
1160 out:
1161 return err < 0 ? err : count;
1162 }
1163
1164 static const struct file_operations proc_oom_adj_operations = {
1165 .read = oom_adj_read,
1166 .write = oom_adj_write,
1167 .llseek = generic_file_llseek,
1168 };
1169
1170 static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1171 size_t count, loff_t *ppos)
1172 {
1173 struct task_struct *task = get_proc_task(file_inode(file));
1174 char buffer[PROC_NUMBUF];
1175 short oom_score_adj = OOM_SCORE_ADJ_MIN;
1176 size_t len;
1177
1178 if (!task)
1179 return -ESRCH;
1180 oom_score_adj = task->signal->oom_score_adj;
1181 put_task_struct(task);
1182 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
1183 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1184 }
1185
1186 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1187 size_t count, loff_t *ppos)
1188 {
1189 char buffer[PROC_NUMBUF];
1190 int oom_score_adj;
1191 int err;
1192
1193 memset(buffer, 0, sizeof(buffer));
1194 if (count > sizeof(buffer) - 1)
1195 count = sizeof(buffer) - 1;
1196 if (copy_from_user(buffer, buf, count)) {
1197 err = -EFAULT;
1198 goto out;
1199 }
1200
1201 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1202 if (err)
1203 goto out;
1204 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1205 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1206 err = -EINVAL;
1207 goto out;
1208 }
1209
1210 err = __set_oom_adj(file, oom_score_adj, false);
1211 out:
1212 return err < 0 ? err : count;
1213 }
1214
1215 static const struct file_operations proc_oom_score_adj_operations = {
1216 .read = oom_score_adj_read,
1217 .write = oom_score_adj_write,
1218 .llseek = default_llseek,
1219 };
1220
1221 #ifdef CONFIG_AUDITSYSCALL
1222 #define TMPBUFLEN 11
1223 static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1224 size_t count, loff_t *ppos)
1225 {
1226 struct inode * inode = file_inode(file);
1227 struct task_struct *task = get_proc_task(inode);
1228 ssize_t length;
1229 char tmpbuf[TMPBUFLEN];
1230
1231 if (!task)
1232 return -ESRCH;
1233 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1234 from_kuid(file->f_cred->user_ns,
1235 audit_get_loginuid(task)));
1236 put_task_struct(task);
1237 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1238 }
1239
1240 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1241 size_t count, loff_t *ppos)
1242 {
1243 struct inode * inode = file_inode(file);
1244 uid_t loginuid;
1245 kuid_t kloginuid;
1246 int rv;
1247
1248 rcu_read_lock();
1249 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1250 rcu_read_unlock();
1251 return -EPERM;
1252 }
1253 rcu_read_unlock();
1254
1255 if (*ppos != 0) {
1256 /* No partial writes. */
1257 return -EINVAL;
1258 }
1259
1260 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1261 if (rv < 0)
1262 return rv;
1263
1264 /* is userspace tring to explicitly UNSET the loginuid? */
1265 if (loginuid == AUDIT_UID_UNSET) {
1266 kloginuid = INVALID_UID;
1267 } else {
1268 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
1269 if (!uid_valid(kloginuid))
1270 return -EINVAL;
1271 }
1272
1273 rv = audit_set_loginuid(kloginuid);
1274 if (rv < 0)
1275 return rv;
1276 return count;
1277 }
1278
1279 static const struct file_operations proc_loginuid_operations = {
1280 .read = proc_loginuid_read,
1281 .write = proc_loginuid_write,
1282 .llseek = generic_file_llseek,
1283 };
1284
1285 static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1286 size_t count, loff_t *ppos)
1287 {
1288 struct inode * inode = file_inode(file);
1289 struct task_struct *task = get_proc_task(inode);
1290 ssize_t length;
1291 char tmpbuf[TMPBUFLEN];
1292
1293 if (!task)
1294 return -ESRCH;
1295 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1296 audit_get_sessionid(task));
1297 put_task_struct(task);
1298 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1299 }
1300
1301 static const struct file_operations proc_sessionid_operations = {
1302 .read = proc_sessionid_read,
1303 .llseek = generic_file_llseek,
1304 };
1305 #endif
1306
1307 #ifdef CONFIG_FAULT_INJECTION
1308 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1309 size_t count, loff_t *ppos)
1310 {
1311 struct task_struct *task = get_proc_task(file_inode(file));
1312 char buffer[PROC_NUMBUF];
1313 size_t len;
1314 int make_it_fail;
1315
1316 if (!task)
1317 return -ESRCH;
1318 make_it_fail = task->make_it_fail;
1319 put_task_struct(task);
1320
1321 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1322
1323 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1324 }
1325
1326 static ssize_t proc_fault_inject_write(struct file * file,
1327 const char __user * buf, size_t count, loff_t *ppos)
1328 {
1329 struct task_struct *task;
1330 char buffer[PROC_NUMBUF];
1331 int make_it_fail;
1332 int rv;
1333
1334 if (!capable(CAP_SYS_RESOURCE))
1335 return -EPERM;
1336 memset(buffer, 0, sizeof(buffer));
1337 if (count > sizeof(buffer) - 1)
1338 count = sizeof(buffer) - 1;
1339 if (copy_from_user(buffer, buf, count))
1340 return -EFAULT;
1341 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1342 if (rv < 0)
1343 return rv;
1344 if (make_it_fail < 0 || make_it_fail > 1)
1345 return -EINVAL;
1346
1347 task = get_proc_task(file_inode(file));
1348 if (!task)
1349 return -ESRCH;
1350 task->make_it_fail = make_it_fail;
1351 put_task_struct(task);
1352
1353 return count;
1354 }
1355
1356 static const struct file_operations proc_fault_inject_operations = {
1357 .read = proc_fault_inject_read,
1358 .write = proc_fault_inject_write,
1359 .llseek = generic_file_llseek,
1360 };
1361
1362 static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf,
1363 size_t count, loff_t *ppos)
1364 {
1365 struct task_struct *task;
1366 int err;
1367 unsigned int n;
1368
1369 err = kstrtouint_from_user(buf, count, 0, &n);
1370 if (err)
1371 return err;
1372
1373 task = get_proc_task(file_inode(file));
1374 if (!task)
1375 return -ESRCH;
1376 task->fail_nth = n;
1377 put_task_struct(task);
1378
1379 return count;
1380 }
1381
1382 static ssize_t proc_fail_nth_read(struct file *file, char __user *buf,
1383 size_t count, loff_t *ppos)
1384 {
1385 struct task_struct *task;
1386 char numbuf[PROC_NUMBUF];
1387 ssize_t len;
1388
1389 task = get_proc_task(file_inode(file));
1390 if (!task)
1391 return -ESRCH;
1392 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth);
1393 len = simple_read_from_buffer(buf, count, ppos, numbuf, len);
1394 put_task_struct(task);
1395
1396 return len;
1397 }
1398
1399 static const struct file_operations proc_fail_nth_operations = {
1400 .read = proc_fail_nth_read,
1401 .write = proc_fail_nth_write,
1402 };
1403 #endif
1404
1405
1406 #ifdef CONFIG_SCHED_DEBUG
1407 /*
1408 * Print out various scheduling related per-task fields:
1409 */
1410 static int sched_show(struct seq_file *m, void *v)
1411 {
1412 struct inode *inode = m->private;
1413 struct pid_namespace *ns = inode->i_sb->s_fs_info;
1414 struct task_struct *p;
1415
1416 p = get_proc_task(inode);
1417 if (!p)
1418 return -ESRCH;
1419 proc_sched_show_task(p, ns, m);
1420
1421 put_task_struct(p);
1422
1423 return 0;
1424 }
1425
1426 static ssize_t
1427 sched_write(struct file *file, const char __user *buf,
1428 size_t count, loff_t *offset)
1429 {
1430 struct inode *inode = file_inode(file);
1431 struct task_struct *p;
1432
1433 p = get_proc_task(inode);
1434 if (!p)
1435 return -ESRCH;
1436 proc_sched_set_task(p);
1437
1438 put_task_struct(p);
1439
1440 return count;
1441 }
1442
1443 static int sched_open(struct inode *inode, struct file *filp)
1444 {
1445 return single_open(filp, sched_show, inode);
1446 }
1447
1448 static const struct file_operations proc_pid_sched_operations = {
1449 .open = sched_open,
1450 .read = seq_read,
1451 .write = sched_write,
1452 .llseek = seq_lseek,
1453 .release = single_release,
1454 };
1455
1456 #endif
1457
1458 #ifdef CONFIG_SCHED_AUTOGROUP
1459 /*
1460 * Print out autogroup related information:
1461 */
1462 static int sched_autogroup_show(struct seq_file *m, void *v)
1463 {
1464 struct inode *inode = m->private;
1465 struct task_struct *p;
1466
1467 p = get_proc_task(inode);
1468 if (!p)
1469 return -ESRCH;
1470 proc_sched_autogroup_show_task(p, m);
1471
1472 put_task_struct(p);
1473
1474 return 0;
1475 }
1476
1477 static ssize_t
1478 sched_autogroup_write(struct file *file, const char __user *buf,
1479 size_t count, loff_t *offset)
1480 {
1481 struct inode *inode = file_inode(file);
1482 struct task_struct *p;
1483 char buffer[PROC_NUMBUF];
1484 int nice;
1485 int err;
1486
1487 memset(buffer, 0, sizeof(buffer));
1488 if (count > sizeof(buffer) - 1)
1489 count = sizeof(buffer) - 1;
1490 if (copy_from_user(buffer, buf, count))
1491 return -EFAULT;
1492
1493 err = kstrtoint(strstrip(buffer), 0, &nice);
1494 if (err < 0)
1495 return err;
1496
1497 p = get_proc_task(inode);
1498 if (!p)
1499 return -ESRCH;
1500
1501 err = proc_sched_autogroup_set_nice(p, nice);
1502 if (err)
1503 count = err;
1504
1505 put_task_struct(p);
1506
1507 return count;
1508 }
1509
1510 static int sched_autogroup_open(struct inode *inode, struct file *filp)
1511 {
1512 int ret;
1513
1514 ret = single_open(filp, sched_autogroup_show, NULL);
1515 if (!ret) {
1516 struct seq_file *m = filp->private_data;
1517
1518 m->private = inode;
1519 }
1520 return ret;
1521 }
1522
1523 static const struct file_operations proc_pid_sched_autogroup_operations = {
1524 .open = sched_autogroup_open,
1525 .read = seq_read,
1526 .write = sched_autogroup_write,
1527 .llseek = seq_lseek,
1528 .release = single_release,
1529 };
1530
1531 #endif /* CONFIG_SCHED_AUTOGROUP */
1532
1533 static ssize_t comm_write(struct file *file, const char __user *buf,
1534 size_t count, loff_t *offset)
1535 {
1536 struct inode *inode = file_inode(file);
1537 struct task_struct *p;
1538 char buffer[TASK_COMM_LEN];
1539 const size_t maxlen = sizeof(buffer) - 1;
1540
1541 memset(buffer, 0, sizeof(buffer));
1542 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
1543 return -EFAULT;
1544
1545 p = get_proc_task(inode);
1546 if (!p)
1547 return -ESRCH;
1548
1549 if (same_thread_group(current, p))
1550 set_task_comm(p, buffer);
1551 else
1552 count = -EINVAL;
1553
1554 put_task_struct(p);
1555
1556 return count;
1557 }
1558
1559 static int comm_show(struct seq_file *m, void *v)
1560 {
1561 struct inode *inode = m->private;
1562 struct task_struct *p;
1563
1564 p = get_proc_task(inode);
1565 if (!p)
1566 return -ESRCH;
1567
1568 task_lock(p);
1569 seq_printf(m, "%s\n", p->comm);
1570 task_unlock(p);
1571
1572 put_task_struct(p);
1573
1574 return 0;
1575 }
1576
1577 static int comm_open(struct inode *inode, struct file *filp)
1578 {
1579 return single_open(filp, comm_show, inode);
1580 }
1581
1582 static const struct file_operations proc_pid_set_comm_operations = {
1583 .open = comm_open,
1584 .read = seq_read,
1585 .write = comm_write,
1586 .llseek = seq_lseek,
1587 .release = single_release,
1588 };
1589
1590 static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1591 {
1592 struct task_struct *task;
1593 struct file *exe_file;
1594
1595 task = get_proc_task(d_inode(dentry));
1596 if (!task)
1597 return -ENOENT;
1598 exe_file = get_task_exe_file(task);
1599 put_task_struct(task);
1600 if (exe_file) {
1601 *exe_path = exe_file->f_path;
1602 path_get(&exe_file->f_path);
1603 fput(exe_file);
1604 return 0;
1605 } else
1606 return -ENOENT;
1607 }
1608
1609 static const char *proc_pid_get_link(struct dentry *dentry,
1610 struct inode *inode,
1611 struct delayed_call *done)
1612 {
1613 struct path path;
1614 int error = -EACCES;
1615
1616 if (!dentry)
1617 return ERR_PTR(-ECHILD);
1618
1619 /* Are we allowed to snoop on the tasks file descriptors? */
1620 if (!proc_fd_access_allowed(inode))
1621 goto out;
1622
1623 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1624 if (error)
1625 goto out;
1626
1627 nd_jump_link(&path);
1628 return NULL;
1629 out:
1630 return ERR_PTR(error);
1631 }
1632
1633 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1634 {
1635 char *tmp = (char *)__get_free_page(GFP_KERNEL);
1636 char *pathname;
1637 int len;
1638
1639 if (!tmp)
1640 return -ENOMEM;
1641
1642 pathname = d_path(path, tmp, PAGE_SIZE);
1643 len = PTR_ERR(pathname);
1644 if (IS_ERR(pathname))
1645 goto out;
1646 len = tmp + PAGE_SIZE - 1 - pathname;
1647
1648 if (len > buflen)
1649 len = buflen;
1650 if (copy_to_user(buffer, pathname, len))
1651 len = -EFAULT;
1652 out:
1653 free_page((unsigned long)tmp);
1654 return len;
1655 }
1656
1657 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1658 {
1659 int error = -EACCES;
1660 struct inode *inode = d_inode(dentry);
1661 struct path path;
1662
1663 /* Are we allowed to snoop on the tasks file descriptors? */
1664 if (!proc_fd_access_allowed(inode))
1665 goto out;
1666
1667 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1668 if (error)
1669 goto out;
1670
1671 error = do_proc_readlink(&path, buffer, buflen);
1672 path_put(&path);
1673 out:
1674 return error;
1675 }
1676
1677 const struct inode_operations proc_pid_link_inode_operations = {
1678 .readlink = proc_pid_readlink,
1679 .get_link = proc_pid_get_link,
1680 .setattr = proc_setattr,
1681 };
1682
1683
1684 /* building an inode */
1685
1686 void task_dump_owner(struct task_struct *task, umode_t mode,
1687 kuid_t *ruid, kgid_t *rgid)
1688 {
1689 /* Depending on the state of dumpable compute who should own a
1690 * proc file for a task.
1691 */
1692 const struct cred *cred;
1693 kuid_t uid;
1694 kgid_t gid;
1695
1696 /* Default to the tasks effective ownership */
1697 rcu_read_lock();
1698 cred = __task_cred(task);
1699 uid = cred->euid;
1700 gid = cred->egid;
1701 rcu_read_unlock();
1702
1703 /*
1704 * Before the /proc/pid/status file was created the only way to read
1705 * the effective uid of a /process was to stat /proc/pid. Reading
1706 * /proc/pid/status is slow enough that procps and other packages
1707 * kept stating /proc/pid. To keep the rules in /proc simple I have
1708 * made this apply to all per process world readable and executable
1709 * directories.
1710 */
1711 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) {
1712 struct mm_struct *mm;
1713 task_lock(task);
1714 mm = task->mm;
1715 /* Make non-dumpable tasks owned by some root */
1716 if (mm) {
1717 if (get_dumpable(mm) != SUID_DUMP_USER) {
1718 struct user_namespace *user_ns = mm->user_ns;
1719
1720 uid = make_kuid(user_ns, 0);
1721 if (!uid_valid(uid))
1722 uid = GLOBAL_ROOT_UID;
1723
1724 gid = make_kgid(user_ns, 0);
1725 if (!gid_valid(gid))
1726 gid = GLOBAL_ROOT_GID;
1727 }
1728 } else {
1729 uid = GLOBAL_ROOT_UID;
1730 gid = GLOBAL_ROOT_GID;
1731 }
1732 task_unlock(task);
1733 }
1734 *ruid = uid;
1735 *rgid = gid;
1736 }
1737
1738 struct inode *proc_pid_make_inode(struct super_block * sb,
1739 struct task_struct *task, umode_t mode)
1740 {
1741 struct inode * inode;
1742 struct proc_inode *ei;
1743
1744 /* We need a new inode */
1745
1746 inode = new_inode(sb);
1747 if (!inode)
1748 goto out;
1749
1750 /* Common stuff */
1751 ei = PROC_I(inode);
1752 inode->i_mode = mode;
1753 inode->i_ino = get_next_ino();
1754 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
1755 inode->i_op = &proc_def_inode_operations;
1756
1757 /*
1758 * grab the reference to task.
1759 */
1760 ei->pid = get_task_pid(task, PIDTYPE_PID);
1761 if (!ei->pid)
1762 goto out_unlock;
1763
1764 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1765 security_task_to_inode(task, inode);
1766
1767 out:
1768 return inode;
1769
1770 out_unlock:
1771 iput(inode);
1772 return NULL;
1773 }
1774
1775 int pid_getattr(const struct path *path, struct kstat *stat,
1776 u32 request_mask, unsigned int query_flags)
1777 {
1778 struct inode *inode = d_inode(path->dentry);
1779 struct task_struct *task;
1780 struct pid_namespace *pid = path->dentry->d_sb->s_fs_info;
1781
1782 generic_fillattr(inode, stat);
1783
1784 rcu_read_lock();
1785 stat->uid = GLOBAL_ROOT_UID;
1786 stat->gid = GLOBAL_ROOT_GID;
1787 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1788 if (task) {
1789 if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) {
1790 rcu_read_unlock();
1791 /*
1792 * This doesn't prevent learning whether PID exists,
1793 * it only makes getattr() consistent with readdir().
1794 */
1795 return -ENOENT;
1796 }
1797 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid);
1798 }
1799 rcu_read_unlock();
1800 return 0;
1801 }
1802
1803 /* dentry stuff */
1804
1805 /*
1806 * Exceptional case: normally we are not allowed to unhash a busy
1807 * directory. In this case, however, we can do it - no aliasing problems
1808 * due to the way we treat inodes.
1809 *
1810 * Rewrite the inode's ownerships here because the owning task may have
1811 * performed a setuid(), etc.
1812 *
1813 */
1814 int pid_revalidate(struct dentry *dentry, unsigned int flags)
1815 {
1816 struct inode *inode;
1817 struct task_struct *task;
1818
1819 if (flags & LOOKUP_RCU)
1820 return -ECHILD;
1821
1822 inode = d_inode(dentry);
1823 task = get_proc_task(inode);
1824
1825 if (task) {
1826 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
1827
1828 inode->i_mode &= ~(S_ISUID | S_ISGID);
1829 security_task_to_inode(task, inode);
1830 put_task_struct(task);
1831 return 1;
1832 }
1833 return 0;
1834 }
1835
1836 static inline bool proc_inode_is_dead(struct inode *inode)
1837 {
1838 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
1839 }
1840
1841 int pid_delete_dentry(const struct dentry *dentry)
1842 {
1843 /* Is the task we represent dead?
1844 * If so, then don't put the dentry on the lru list,
1845 * kill it immediately.
1846 */
1847 return proc_inode_is_dead(d_inode(dentry));
1848 }
1849
1850 const struct dentry_operations pid_dentry_operations =
1851 {
1852 .d_revalidate = pid_revalidate,
1853 .d_delete = pid_delete_dentry,
1854 };
1855
1856 /* Lookups */
1857
1858 /*
1859 * Fill a directory entry.
1860 *
1861 * If possible create the dcache entry and derive our inode number and
1862 * file type from dcache entry.
1863 *
1864 * Since all of the proc inode numbers are dynamically generated, the inode
1865 * numbers do not exist until the inode is cache. This means creating the
1866 * the dcache entry in readdir is necessary to keep the inode numbers
1867 * reported by readdir in sync with the inode numbers reported
1868 * by stat.
1869 */
1870 bool proc_fill_cache(struct file *file, struct dir_context *ctx,
1871 const char *name, int len,
1872 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1873 {
1874 struct dentry *child, *dir = file->f_path.dentry;
1875 struct qstr qname = QSTR_INIT(name, len);
1876 struct inode *inode;
1877 unsigned type;
1878 ino_t ino;
1879
1880 child = d_hash_and_lookup(dir, &qname);
1881 if (!child) {
1882 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
1883 child = d_alloc_parallel(dir, &qname, &wq);
1884 if (IS_ERR(child))
1885 goto end_instantiate;
1886 if (d_in_lookup(child)) {
1887 int err = instantiate(d_inode(dir), child, task, ptr);
1888 d_lookup_done(child);
1889 if (err < 0) {
1890 dput(child);
1891 goto end_instantiate;
1892 }
1893 }
1894 }
1895 inode = d_inode(child);
1896 ino = inode->i_ino;
1897 type = inode->i_mode >> 12;
1898 dput(child);
1899 return dir_emit(ctx, name, len, ino, type);
1900
1901 end_instantiate:
1902 return dir_emit(ctx, name, len, 1, DT_UNKNOWN);
1903 }
1904
1905 /*
1906 * dname_to_vma_addr - maps a dentry name into two unsigned longs
1907 * which represent vma start and end addresses.
1908 */
1909 static int dname_to_vma_addr(struct dentry *dentry,
1910 unsigned long *start, unsigned long *end)
1911 {
1912 const char *str = dentry->d_name.name;
1913 unsigned long long sval, eval;
1914 unsigned int len;
1915
1916 len = _parse_integer(str, 16, &sval);
1917 if (len & KSTRTOX_OVERFLOW)
1918 return -EINVAL;
1919 if (sval != (unsigned long)sval)
1920 return -EINVAL;
1921 str += len;
1922
1923 if (*str != '-')
1924 return -EINVAL;
1925 str++;
1926
1927 len = _parse_integer(str, 16, &eval);
1928 if (len & KSTRTOX_OVERFLOW)
1929 return -EINVAL;
1930 if (eval != (unsigned long)eval)
1931 return -EINVAL;
1932 str += len;
1933
1934 if (*str != '\0')
1935 return -EINVAL;
1936
1937 *start = sval;
1938 *end = eval;
1939
1940 return 0;
1941 }
1942
1943 static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
1944 {
1945 unsigned long vm_start, vm_end;
1946 bool exact_vma_exists = false;
1947 struct mm_struct *mm = NULL;
1948 struct task_struct *task;
1949 struct inode *inode;
1950 int status = 0;
1951
1952 if (flags & LOOKUP_RCU)
1953 return -ECHILD;
1954
1955 inode = d_inode(dentry);
1956 task = get_proc_task(inode);
1957 if (!task)
1958 goto out_notask;
1959
1960 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
1961 if (IS_ERR_OR_NULL(mm))
1962 goto out;
1963
1964 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
1965 down_read(&mm->mmap_sem);
1966 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
1967 up_read(&mm->mmap_sem);
1968 }
1969
1970 mmput(mm);
1971
1972 if (exact_vma_exists) {
1973 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1974
1975 security_task_to_inode(task, inode);
1976 status = 1;
1977 }
1978
1979 out:
1980 put_task_struct(task);
1981
1982 out_notask:
1983 return status;
1984 }
1985
1986 static const struct dentry_operations tid_map_files_dentry_operations = {
1987 .d_revalidate = map_files_d_revalidate,
1988 .d_delete = pid_delete_dentry,
1989 };
1990
1991 static int map_files_get_link(struct dentry *dentry, struct path *path)
1992 {
1993 unsigned long vm_start, vm_end;
1994 struct vm_area_struct *vma;
1995 struct task_struct *task;
1996 struct mm_struct *mm;
1997 int rc;
1998
1999 rc = -ENOENT;
2000 task = get_proc_task(d_inode(dentry));
2001 if (!task)
2002 goto out;
2003
2004 mm = get_task_mm(task);
2005 put_task_struct(task);
2006 if (!mm)
2007 goto out;
2008
2009 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2010 if (rc)
2011 goto out_mmput;
2012
2013 rc = -ENOENT;
2014 down_read(&mm->mmap_sem);
2015 vma = find_exact_vma(mm, vm_start, vm_end);
2016 if (vma && vma->vm_file) {
2017 *path = vma->vm_file->f_path;
2018 path_get(path);
2019 rc = 0;
2020 }
2021 up_read(&mm->mmap_sem);
2022
2023 out_mmput:
2024 mmput(mm);
2025 out:
2026 return rc;
2027 }
2028
2029 struct map_files_info {
2030 unsigned long start;
2031 unsigned long end;
2032 fmode_t mode;
2033 };
2034
2035 /*
2036 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the
2037 * symlinks may be used to bypass permissions on ancestor directories in the
2038 * path to the file in question.
2039 */
2040 static const char *
2041 proc_map_files_get_link(struct dentry *dentry,
2042 struct inode *inode,
2043 struct delayed_call *done)
2044 {
2045 if (!capable(CAP_SYS_ADMIN))
2046 return ERR_PTR(-EPERM);
2047
2048 return proc_pid_get_link(dentry, inode, done);
2049 }
2050
2051 /*
2052 * Identical to proc_pid_link_inode_operations except for get_link()
2053 */
2054 static const struct inode_operations proc_map_files_link_inode_operations = {
2055 .readlink = proc_pid_readlink,
2056 .get_link = proc_map_files_get_link,
2057 .setattr = proc_setattr,
2058 };
2059
2060 static int
2061 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2062 struct task_struct *task, const void *ptr)
2063 {
2064 fmode_t mode = (fmode_t)(unsigned long)ptr;
2065 struct proc_inode *ei;
2066 struct inode *inode;
2067
2068 inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK |
2069 ((mode & FMODE_READ ) ? S_IRUSR : 0) |
2070 ((mode & FMODE_WRITE) ? S_IWUSR : 0));
2071 if (!inode)
2072 return -ENOENT;
2073
2074 ei = PROC_I(inode);
2075 ei->op.proc_get_link = map_files_get_link;
2076
2077 inode->i_op = &proc_map_files_link_inode_operations;
2078 inode->i_size = 64;
2079
2080 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2081 d_add(dentry, inode);
2082
2083 return 0;
2084 }
2085
2086 static struct dentry *proc_map_files_lookup(struct inode *dir,
2087 struct dentry *dentry, unsigned int flags)
2088 {
2089 unsigned long vm_start, vm_end;
2090 struct vm_area_struct *vma;
2091 struct task_struct *task;
2092 int result;
2093 struct mm_struct *mm;
2094
2095 result = -ENOENT;
2096 task = get_proc_task(dir);
2097 if (!task)
2098 goto out;
2099
2100 result = -EACCES;
2101 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2102 goto out_put_task;
2103
2104 result = -ENOENT;
2105 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2106 goto out_put_task;
2107
2108 mm = get_task_mm(task);
2109 if (!mm)
2110 goto out_put_task;
2111
2112 down_read(&mm->mmap_sem);
2113 vma = find_exact_vma(mm, vm_start, vm_end);
2114 if (!vma)
2115 goto out_no_vma;
2116
2117 if (vma->vm_file)
2118 result = proc_map_files_instantiate(dir, dentry, task,
2119 (void *)(unsigned long)vma->vm_file->f_mode);
2120
2121 out_no_vma:
2122 up_read(&mm->mmap_sem);
2123 mmput(mm);
2124 out_put_task:
2125 put_task_struct(task);
2126 out:
2127 return ERR_PTR(result);
2128 }
2129
2130 static const struct inode_operations proc_map_files_inode_operations = {
2131 .lookup = proc_map_files_lookup,
2132 .permission = proc_fd_permission,
2133 .setattr = proc_setattr,
2134 };
2135
2136 static int
2137 proc_map_files_readdir(struct file *file, struct dir_context *ctx)
2138 {
2139 struct vm_area_struct *vma;
2140 struct task_struct *task;
2141 struct mm_struct *mm;
2142 unsigned long nr_files, pos, i;
2143 struct flex_array *fa = NULL;
2144 struct map_files_info info;
2145 struct map_files_info *p;
2146 int ret;
2147
2148 ret = -ENOENT;
2149 task = get_proc_task(file_inode(file));
2150 if (!task)
2151 goto out;
2152
2153 ret = -EACCES;
2154 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2155 goto out_put_task;
2156
2157 ret = 0;
2158 if (!dir_emit_dots(file, ctx))
2159 goto out_put_task;
2160
2161 mm = get_task_mm(task);
2162 if (!mm)
2163 goto out_put_task;
2164 down_read(&mm->mmap_sem);
2165
2166 nr_files = 0;
2167
2168 /*
2169 * We need two passes here:
2170 *
2171 * 1) Collect vmas of mapped files with mmap_sem taken
2172 * 2) Release mmap_sem and instantiate entries
2173 *
2174 * otherwise we get lockdep complained, since filldir()
2175 * routine might require mmap_sem taken in might_fault().
2176 */
2177
2178 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2179 if (vma->vm_file && ++pos > ctx->pos)
2180 nr_files++;
2181 }
2182
2183 if (nr_files) {
2184 fa = flex_array_alloc(sizeof(info), nr_files,
2185 GFP_KERNEL);
2186 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2187 GFP_KERNEL)) {
2188 ret = -ENOMEM;
2189 if (fa)
2190 flex_array_free(fa);
2191 up_read(&mm->mmap_sem);
2192 mmput(mm);
2193 goto out_put_task;
2194 }
2195 for (i = 0, vma = mm->mmap, pos = 2; vma;
2196 vma = vma->vm_next) {
2197 if (!vma->vm_file)
2198 continue;
2199 if (++pos <= ctx->pos)
2200 continue;
2201
2202 info.start = vma->vm_start;
2203 info.end = vma->vm_end;
2204 info.mode = vma->vm_file->f_mode;
2205 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2206 BUG();
2207 }
2208 }
2209 up_read(&mm->mmap_sem);
2210
2211 for (i = 0; i < nr_files; i++) {
2212 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */
2213 unsigned int len;
2214
2215 p = flex_array_get(fa, i);
2216 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);
2217 if (!proc_fill_cache(file, ctx,
2218 buf, len,
2219 proc_map_files_instantiate,
2220 task,
2221 (void *)(unsigned long)p->mode))
2222 break;
2223 ctx->pos++;
2224 }
2225 if (fa)
2226 flex_array_free(fa);
2227 mmput(mm);
2228
2229 out_put_task:
2230 put_task_struct(task);
2231 out:
2232 return ret;
2233 }
2234
2235 static const struct file_operations proc_map_files_operations = {
2236 .read = generic_read_dir,
2237 .iterate_shared = proc_map_files_readdir,
2238 .llseek = generic_file_llseek,
2239 };
2240
2241 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
2242 struct timers_private {
2243 struct pid *pid;
2244 struct task_struct *task;
2245 struct sighand_struct *sighand;
2246 struct pid_namespace *ns;
2247 unsigned long flags;
2248 };
2249
2250 static void *timers_start(struct seq_file *m, loff_t *pos)
2251 {
2252 struct timers_private *tp = m->private;
2253
2254 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2255 if (!tp->task)
2256 return ERR_PTR(-ESRCH);
2257
2258 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2259 if (!tp->sighand)
2260 return ERR_PTR(-ESRCH);
2261
2262 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2263 }
2264
2265 static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2266 {
2267 struct timers_private *tp = m->private;
2268 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2269 }
2270
2271 static void timers_stop(struct seq_file *m, void *v)
2272 {
2273 struct timers_private *tp = m->private;
2274
2275 if (tp->sighand) {
2276 unlock_task_sighand(tp->task, &tp->flags);
2277 tp->sighand = NULL;
2278 }
2279
2280 if (tp->task) {
2281 put_task_struct(tp->task);
2282 tp->task = NULL;
2283 }
2284 }
2285
2286 static int show_timer(struct seq_file *m, void *v)
2287 {
2288 struct k_itimer *timer;
2289 struct timers_private *tp = m->private;
2290 int notify;
2291 static const char * const nstr[] = {
2292 [SIGEV_SIGNAL] = "signal",
2293 [SIGEV_NONE] = "none",
2294 [SIGEV_THREAD] = "thread",
2295 };
2296
2297 timer = list_entry((struct list_head *)v, struct k_itimer, list);
2298 notify = timer->it_sigev_notify;
2299
2300 seq_printf(m, "ID: %d\n", timer->it_id);
2301 seq_printf(m, "signal: %d/%px\n",
2302 timer->sigq->info.si_signo,
2303 timer->sigq->info.si_value.sival_ptr);
2304 seq_printf(m, "notify: %s/%s.%d\n",
2305 nstr[notify & ~SIGEV_THREAD_ID],
2306 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2307 pid_nr_ns(timer->it_pid, tp->ns));
2308 seq_printf(m, "ClockID: %d\n", timer->it_clock);
2309
2310 return 0;
2311 }
2312
2313 static const struct seq_operations proc_timers_seq_ops = {
2314 .start = timers_start,
2315 .next = timers_next,
2316 .stop = timers_stop,
2317 .show = show_timer,
2318 };
2319
2320 static int proc_timers_open(struct inode *inode, struct file *file)
2321 {
2322 struct timers_private *tp;
2323
2324 tp = __seq_open_private(file, &proc_timers_seq_ops,
2325 sizeof(struct timers_private));
2326 if (!tp)
2327 return -ENOMEM;
2328
2329 tp->pid = proc_pid(inode);
2330 tp->ns = inode->i_sb->s_fs_info;
2331 return 0;
2332 }
2333
2334 static const struct file_operations proc_timers_operations = {
2335 .open = proc_timers_open,
2336 .read = seq_read,
2337 .llseek = seq_lseek,
2338 .release = seq_release_private,
2339 };
2340 #endif
2341
2342 static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2343 size_t count, loff_t *offset)
2344 {
2345 struct inode *inode = file_inode(file);
2346 struct task_struct *p;
2347 u64 slack_ns;
2348 int err;
2349
2350 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2351 if (err < 0)
2352 return err;
2353
2354 p = get_proc_task(inode);
2355 if (!p)
2356 return -ESRCH;
2357
2358 if (p != current) {
2359 if (!capable(CAP_SYS_NICE)) {
2360 count = -EPERM;
2361 goto out;
2362 }
2363
2364 err = security_task_setscheduler(p);
2365 if (err) {
2366 count = err;
2367 goto out;
2368 }
2369 }
2370
2371 task_lock(p);
2372 if (slack_ns == 0)
2373 p->timer_slack_ns = p->default_timer_slack_ns;
2374 else
2375 p->timer_slack_ns = slack_ns;
2376 task_unlock(p);
2377
2378 out:
2379 put_task_struct(p);
2380
2381 return count;
2382 }
2383
2384 static int timerslack_ns_show(struct seq_file *m, void *v)
2385 {
2386 struct inode *inode = m->private;
2387 struct task_struct *p;
2388 int err = 0;
2389
2390 p = get_proc_task(inode);
2391 if (!p)
2392 return -ESRCH;
2393
2394 if (p != current) {
2395
2396 if (!capable(CAP_SYS_NICE)) {
2397 err = -EPERM;
2398 goto out;
2399 }
2400 err = security_task_getscheduler(p);
2401 if (err)
2402 goto out;
2403 }
2404
2405 task_lock(p);
2406 seq_printf(m, "%llu\n", p->timer_slack_ns);
2407 task_unlock(p);
2408
2409 out:
2410 put_task_struct(p);
2411
2412 return err;
2413 }
2414
2415 static int timerslack_ns_open(struct inode *inode, struct file *filp)
2416 {
2417 return single_open(filp, timerslack_ns_show, inode);
2418 }
2419
2420 static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2421 .open = timerslack_ns_open,
2422 .read = seq_read,
2423 .write = timerslack_ns_write,
2424 .llseek = seq_lseek,
2425 .release = single_release,
2426 };
2427
2428 static int proc_pident_instantiate(struct inode *dir,
2429 struct dentry *dentry, struct task_struct *task, const void *ptr)
2430 {
2431 const struct pid_entry *p = ptr;
2432 struct inode *inode;
2433 struct proc_inode *ei;
2434
2435 inode = proc_pid_make_inode(dir->i_sb, task, p->mode);
2436 if (!inode)
2437 goto out;
2438
2439 ei = PROC_I(inode);
2440 if (S_ISDIR(inode->i_mode))
2441 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2442 if (p->iop)
2443 inode->i_op = p->iop;
2444 if (p->fop)
2445 inode->i_fop = p->fop;
2446 ei->op = p->op;
2447 d_set_d_op(dentry, &pid_dentry_operations);
2448 d_add(dentry, inode);
2449 /* Close the race of the process dying before we return the dentry */
2450 if (pid_revalidate(dentry, 0))
2451 return 0;
2452 out:
2453 return -ENOENT;
2454 }
2455
2456 static struct dentry *proc_pident_lookup(struct inode *dir,
2457 struct dentry *dentry,
2458 const struct pid_entry *ents,
2459 unsigned int nents)
2460 {
2461 int error;
2462 struct task_struct *task = get_proc_task(dir);
2463 const struct pid_entry *p, *last;
2464
2465 error = -ENOENT;
2466
2467 if (!task)
2468 goto out_no_task;
2469
2470 /*
2471 * Yes, it does not scale. And it should not. Don't add
2472 * new entries into /proc/<tgid>/ without very good reasons.
2473 */
2474 last = &ents[nents];
2475 for (p = ents; p < last; p++) {
2476 if (p->len != dentry->d_name.len)
2477 continue;
2478 if (!memcmp(dentry->d_name.name, p->name, p->len))
2479 break;
2480 }
2481 if (p >= last)
2482 goto out;
2483
2484 error = proc_pident_instantiate(dir, dentry, task, p);
2485 out:
2486 put_task_struct(task);
2487 out_no_task:
2488 return ERR_PTR(error);
2489 }
2490
2491 static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
2492 const struct pid_entry *ents, unsigned int nents)
2493 {
2494 struct task_struct *task = get_proc_task(file_inode(file));
2495 const struct pid_entry *p;
2496
2497 if (!task)
2498 return -ENOENT;
2499
2500 if (!dir_emit_dots(file, ctx))
2501 goto out;
2502
2503 if (ctx->pos >= nents + 2)
2504 goto out;
2505
2506 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
2507 if (!proc_fill_cache(file, ctx, p->name, p->len,
2508 proc_pident_instantiate, task, p))
2509 break;
2510 ctx->pos++;
2511 }
2512 out:
2513 put_task_struct(task);
2514 return 0;
2515 }
2516
2517 #ifdef CONFIG_SECURITY
2518 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2519 size_t count, loff_t *ppos)
2520 {
2521 struct inode * inode = file_inode(file);
2522 char *p = NULL;
2523 ssize_t length;
2524 struct task_struct *task = get_proc_task(inode);
2525
2526 if (!task)
2527 return -ESRCH;
2528
2529 length = security_getprocattr(task,
2530 (char*)file->f_path.dentry->d_name.name,
2531 &p);
2532 put_task_struct(task);
2533 if (length > 0)
2534 length = simple_read_from_buffer(buf, count, ppos, p, length);
2535 kfree(p);
2536 return length;
2537 }
2538
2539 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2540 size_t count, loff_t *ppos)
2541 {
2542 struct inode * inode = file_inode(file);
2543 void *page;
2544 ssize_t length;
2545 struct task_struct *task = get_proc_task(inode);
2546
2547 length = -ESRCH;
2548 if (!task)
2549 goto out_no_task;
2550
2551 /* A task may only write its own attributes. */
2552 length = -EACCES;
2553 if (current != task)
2554 goto out;
2555
2556 if (count > PAGE_SIZE)
2557 count = PAGE_SIZE;
2558
2559 /* No partial writes. */
2560 length = -EINVAL;
2561 if (*ppos != 0)
2562 goto out;
2563
2564 page = memdup_user(buf, count);
2565 if (IS_ERR(page)) {
2566 length = PTR_ERR(page);
2567 goto out;
2568 }
2569
2570 /* Guard against adverse ptrace interaction */
2571 length = mutex_lock_interruptible(&current->signal->cred_guard_mutex);
2572 if (length < 0)
2573 goto out_free;
2574
2575 length = security_setprocattr(file->f_path.dentry->d_name.name,
2576 page, count);
2577 mutex_unlock(&current->signal->cred_guard_mutex);
2578 out_free:
2579 kfree(page);
2580 out:
2581 put_task_struct(task);
2582 out_no_task:
2583 return length;
2584 }
2585
2586 static const struct file_operations proc_pid_attr_operations = {
2587 .read = proc_pid_attr_read,
2588 .write = proc_pid_attr_write,
2589 .llseek = generic_file_llseek,
2590 };
2591
2592 static const struct pid_entry attr_dir_stuff[] = {
2593 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2594 REG("prev", S_IRUGO, proc_pid_attr_operations),
2595 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2596 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2597 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2598 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2599 };
2600
2601 static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
2602 {
2603 return proc_pident_readdir(file, ctx,
2604 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2605 }
2606
2607 static const struct file_operations proc_attr_dir_operations = {
2608 .read = generic_read_dir,
2609 .iterate_shared = proc_attr_dir_readdir,
2610 .llseek = generic_file_llseek,
2611 };
2612
2613 static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2614 struct dentry *dentry, unsigned int flags)
2615 {
2616 return proc_pident_lookup(dir, dentry,
2617 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2618 }
2619
2620 static const struct inode_operations proc_attr_dir_inode_operations = {
2621 .lookup = proc_attr_dir_lookup,
2622 .getattr = pid_getattr,
2623 .setattr = proc_setattr,
2624 };
2625
2626 #endif
2627
2628 #ifdef CONFIG_ELF_CORE
2629 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2630 size_t count, loff_t *ppos)
2631 {
2632 struct task_struct *task = get_proc_task(file_inode(file));
2633 struct mm_struct *mm;
2634 char buffer[PROC_NUMBUF];
2635 size_t len;
2636 int ret;
2637
2638 if (!task)
2639 return -ESRCH;
2640
2641 ret = 0;
2642 mm = get_task_mm(task);
2643 if (mm) {
2644 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2645 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2646 MMF_DUMP_FILTER_SHIFT));
2647 mmput(mm);
2648 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2649 }
2650
2651 put_task_struct(task);
2652
2653 return ret;
2654 }
2655
2656 static ssize_t proc_coredump_filter_write(struct file *file,
2657 const char __user *buf,
2658 size_t count,
2659 loff_t *ppos)
2660 {
2661 struct task_struct *task;
2662 struct mm_struct *mm;
2663 unsigned int val;
2664 int ret;
2665 int i;
2666 unsigned long mask;
2667
2668 ret = kstrtouint_from_user(buf, count, 0, &val);
2669 if (ret < 0)
2670 return ret;
2671
2672 ret = -ESRCH;
2673 task = get_proc_task(file_inode(file));
2674 if (!task)
2675 goto out_no_task;
2676
2677 mm = get_task_mm(task);
2678 if (!mm)
2679 goto out_no_mm;
2680 ret = 0;
2681
2682 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2683 if (val & mask)
2684 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2685 else
2686 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2687 }
2688
2689 mmput(mm);
2690 out_no_mm:
2691 put_task_struct(task);
2692 out_no_task:
2693 if (ret < 0)
2694 return ret;
2695 return count;
2696 }
2697
2698 static const struct file_operations proc_coredump_filter_operations = {
2699 .read = proc_coredump_filter_read,
2700 .write = proc_coredump_filter_write,
2701 .llseek = generic_file_llseek,
2702 };
2703 #endif
2704
2705 #ifdef CONFIG_TASK_IO_ACCOUNTING
2706 static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
2707 {
2708 struct task_io_accounting acct = task->ioac;
2709 unsigned long flags;
2710 int result;
2711
2712 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2713 if (result)
2714 return result;
2715
2716 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
2717 result = -EACCES;
2718 goto out_unlock;
2719 }
2720
2721 if (whole && lock_task_sighand(task, &flags)) {
2722 struct task_struct *t = task;
2723
2724 task_io_accounting_add(&acct, &task->signal->ioac);
2725 while_each_thread(task, t)
2726 task_io_accounting_add(&acct, &t->ioac);
2727
2728 unlock_task_sighand(task, &flags);
2729 }
2730 seq_printf(m,
2731 "rchar: %llu\n"
2732 "wchar: %llu\n"
2733 "syscr: %llu\n"
2734 "syscw: %llu\n"
2735 "read_bytes: %llu\n"
2736 "write_bytes: %llu\n"
2737 "cancelled_write_bytes: %llu\n",
2738 (unsigned long long)acct.rchar,
2739 (unsigned long long)acct.wchar,
2740 (unsigned long long)acct.syscr,
2741 (unsigned long long)acct.syscw,
2742 (unsigned long long)acct.read_bytes,
2743 (unsigned long long)acct.write_bytes,
2744 (unsigned long long)acct.cancelled_write_bytes);
2745 result = 0;
2746
2747 out_unlock:
2748 mutex_unlock(&task->signal->cred_guard_mutex);
2749 return result;
2750 }
2751
2752 static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2753 struct pid *pid, struct task_struct *task)
2754 {
2755 return do_io_accounting(task, m, 0);
2756 }
2757
2758 static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2759 struct pid *pid, struct task_struct *task)
2760 {
2761 return do_io_accounting(task, m, 1);
2762 }
2763 #endif /* CONFIG_TASK_IO_ACCOUNTING */
2764
2765 #ifdef CONFIG_USER_NS
2766 static int proc_id_map_open(struct inode *inode, struct file *file,
2767 const struct seq_operations *seq_ops)
2768 {
2769 struct user_namespace *ns = NULL;
2770 struct task_struct *task;
2771 struct seq_file *seq;
2772 int ret = -EINVAL;
2773
2774 task = get_proc_task(inode);
2775 if (task) {
2776 rcu_read_lock();
2777 ns = get_user_ns(task_cred_xxx(task, user_ns));
2778 rcu_read_unlock();
2779 put_task_struct(task);
2780 }
2781 if (!ns)
2782 goto err;
2783
2784 ret = seq_open(file, seq_ops);
2785 if (ret)
2786 goto err_put_ns;
2787
2788 seq = file->private_data;
2789 seq->private = ns;
2790
2791 return 0;
2792 err_put_ns:
2793 put_user_ns(ns);
2794 err:
2795 return ret;
2796 }
2797
2798 static int proc_id_map_release(struct inode *inode, struct file *file)
2799 {
2800 struct seq_file *seq = file->private_data;
2801 struct user_namespace *ns = seq->private;
2802 put_user_ns(ns);
2803 return seq_release(inode, file);
2804 }
2805
2806 static int proc_uid_map_open(struct inode *inode, struct file *file)
2807 {
2808 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2809 }
2810
2811 static int proc_gid_map_open(struct inode *inode, struct file *file)
2812 {
2813 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2814 }
2815
2816 static int proc_projid_map_open(struct inode *inode, struct file *file)
2817 {
2818 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
2819 }
2820
2821 static const struct file_operations proc_uid_map_operations = {
2822 .open = proc_uid_map_open,
2823 .write = proc_uid_map_write,
2824 .read = seq_read,
2825 .llseek = seq_lseek,
2826 .release = proc_id_map_release,
2827 };
2828
2829 static const struct file_operations proc_gid_map_operations = {
2830 .open = proc_gid_map_open,
2831 .write = proc_gid_map_write,
2832 .read = seq_read,
2833 .llseek = seq_lseek,
2834 .release = proc_id_map_release,
2835 };
2836
2837 static const struct file_operations proc_projid_map_operations = {
2838 .open = proc_projid_map_open,
2839 .write = proc_projid_map_write,
2840 .read = seq_read,
2841 .llseek = seq_lseek,
2842 .release = proc_id_map_release,
2843 };
2844
2845 static int proc_setgroups_open(struct inode *inode, struct file *file)
2846 {
2847 struct user_namespace *ns = NULL;
2848 struct task_struct *task;
2849 int ret;
2850
2851 ret = -ESRCH;
2852 task = get_proc_task(inode);
2853 if (task) {
2854 rcu_read_lock();
2855 ns = get_user_ns(task_cred_xxx(task, user_ns));
2856 rcu_read_unlock();
2857 put_task_struct(task);
2858 }
2859 if (!ns)
2860 goto err;
2861
2862 if (file->f_mode & FMODE_WRITE) {
2863 ret = -EACCES;
2864 if (!ns_capable(ns, CAP_SYS_ADMIN))
2865 goto err_put_ns;
2866 }
2867
2868 ret = single_open(file, &proc_setgroups_show, ns);
2869 if (ret)
2870 goto err_put_ns;
2871
2872 return 0;
2873 err_put_ns:
2874 put_user_ns(ns);
2875 err:
2876 return ret;
2877 }
2878
2879 static int proc_setgroups_release(struct inode *inode, struct file *file)
2880 {
2881 struct seq_file *seq = file->private_data;
2882 struct user_namespace *ns = seq->private;
2883 int ret = single_release(inode, file);
2884 put_user_ns(ns);
2885 return ret;
2886 }
2887
2888 static const struct file_operations proc_setgroups_operations = {
2889 .open = proc_setgroups_open,
2890 .write = proc_setgroups_write,
2891 .read = seq_read,
2892 .llseek = seq_lseek,
2893 .release = proc_setgroups_release,
2894 };
2895 #endif /* CONFIG_USER_NS */
2896
2897 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2898 struct pid *pid, struct task_struct *task)
2899 {
2900 int err = lock_trace(task);
2901 if (!err) {
2902 seq_printf(m, "%08x\n", task->personality);
2903 unlock_trace(task);
2904 }
2905 return err;
2906 }
2907
2908 #ifdef CONFIG_LIVEPATCH
2909 static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns,
2910 struct pid *pid, struct task_struct *task)
2911 {
2912 seq_printf(m, "%d\n", task->patch_state);
2913 return 0;
2914 }
2915 #endif /* CONFIG_LIVEPATCH */
2916
2917 /*
2918 * Thread groups
2919 */
2920 static const struct file_operations proc_task_operations;
2921 static const struct inode_operations proc_task_inode_operations;
2922
2923 static const struct pid_entry tgid_base_stuff[] = {
2924 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2925 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2926 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
2927 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2928 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
2929 #ifdef CONFIG_NET
2930 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
2931 #endif
2932 REG("environ", S_IRUSR, proc_environ_operations),
2933 REG("auxv", S_IRUSR, proc_auxv_operations),
2934 ONE("status", S_IRUGO, proc_pid_status),
2935 ONE("personality", S_IRUSR, proc_pid_personality),
2936 ONE("limits", S_IRUGO, proc_pid_limits),
2937 #ifdef CONFIG_SCHED_DEBUG
2938 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2939 #endif
2940 #ifdef CONFIG_SCHED_AUTOGROUP
2941 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
2942 #endif
2943 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2944 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2945 ONE("syscall", S_IRUSR, proc_pid_syscall),
2946 #endif
2947 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
2948 ONE("stat", S_IRUGO, proc_tgid_stat),
2949 ONE("statm", S_IRUGO, proc_pid_statm),
2950 REG("maps", S_IRUGO, proc_pid_maps_operations),
2951 #ifdef CONFIG_NUMA
2952 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
2953 #endif
2954 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2955 LNK("cwd", proc_cwd_link),
2956 LNK("root", proc_root_link),
2957 LNK("exe", proc_exe_link),
2958 REG("mounts", S_IRUGO, proc_mounts_operations),
2959 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2960 REG("mountstats", S_IRUSR, proc_mountstats_operations),
2961 #ifdef CONFIG_PROC_PAGE_MONITOR
2962 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2963 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
2964 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
2965 REG("pagemap", S_IRUSR, proc_pagemap_operations),
2966 #endif
2967 #ifdef CONFIG_SECURITY
2968 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
2969 #endif
2970 #ifdef CONFIG_KALLSYMS
2971 ONE("wchan", S_IRUGO, proc_pid_wchan),
2972 #endif
2973 #ifdef CONFIG_STACKTRACE
2974 ONE("stack", S_IRUSR, proc_pid_stack),
2975 #endif
2976 #ifdef CONFIG_SCHED_INFO
2977 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
2978 #endif
2979 #ifdef CONFIG_LATENCYTOP
2980 REG("latency", S_IRUGO, proc_lstats_operations),
2981 #endif
2982 #ifdef CONFIG_PROC_PID_CPUSET
2983 ONE("cpuset", S_IRUGO, proc_cpuset_show),
2984 #endif
2985 #ifdef CONFIG_CGROUPS
2986 ONE("cgroup", S_IRUGO, proc_cgroup_show),
2987 #endif
2988 ONE("oom_score", S_IRUGO, proc_oom_score),
2989 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
2990 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
2991 #ifdef CONFIG_AUDITSYSCALL
2992 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2993 REG("sessionid", S_IRUGO, proc_sessionid_operations),
2994 #endif
2995 #ifdef CONFIG_FAULT_INJECTION
2996 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
2997 REG("fail-nth", 0644, proc_fail_nth_operations),
2998 #endif
2999 #ifdef CONFIG_ELF_CORE
3000 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3001 #endif
3002 #ifdef CONFIG_TASK_IO_ACCOUNTING
3003 ONE("io", S_IRUSR, proc_tgid_io_accounting),
3004 #endif
3005 #ifdef CONFIG_HARDWALL
3006 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
3007 #endif
3008 #ifdef CONFIG_USER_NS
3009 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3010 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3011 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3012 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3013 #endif
3014 #if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
3015 REG("timers", S_IRUGO, proc_timers_operations),
3016 #endif
3017 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
3018 #ifdef CONFIG_LIVEPATCH
3019 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3020 #endif
3021 };
3022
3023 static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
3024 {
3025 return proc_pident_readdir(file, ctx,
3026 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3027 }
3028
3029 static const struct file_operations proc_tgid_base_operations = {
3030 .read = generic_read_dir,
3031 .iterate_shared = proc_tgid_base_readdir,
3032 .llseek = generic_file_llseek,
3033 };
3034
3035 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3036 {
3037 return proc_pident_lookup(dir, dentry,
3038 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3039 }
3040
3041 static const struct inode_operations proc_tgid_base_inode_operations = {
3042 .lookup = proc_tgid_base_lookup,
3043 .getattr = pid_getattr,
3044 .setattr = proc_setattr,
3045 .permission = proc_pid_permission,
3046 };
3047
3048 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
3049 {
3050 struct dentry *dentry, *leader, *dir;
3051 char buf[10 + 1];
3052 struct qstr name;
3053
3054 name.name = buf;
3055 name.len = snprintf(buf, sizeof(buf), "%u", pid);
3056 /* no ->d_hash() rejects on procfs */
3057 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
3058 if (dentry) {
3059 d_invalidate(dentry);
3060 dput(dentry);
3061 }
3062
3063 if (pid == tgid)
3064 return;
3065
3066 name.name = buf;
3067 name.len = snprintf(buf, sizeof(buf), "%u", tgid);
3068 leader = d_hash_and_lookup(mnt->mnt_root, &name);
3069 if (!leader)
3070 goto out;
3071
3072 name.name = "task";
3073 name.len = strlen(name.name);
3074 dir = d_hash_and_lookup(leader, &name);
3075 if (!dir)
3076 goto out_put_leader;
3077
3078 name.name = buf;
3079 name.len = snprintf(buf, sizeof(buf), "%u", pid);
3080 dentry = d_hash_and_lookup(dir, &name);
3081 if (dentry) {
3082 d_invalidate(dentry);
3083 dput(dentry);
3084 }
3085
3086 dput(dir);
3087 out_put_leader:
3088 dput(leader);
3089 out:
3090 return;
3091 }
3092
3093 /**
3094 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3095 * @task: task that should be flushed.
3096 *
3097 * When flushing dentries from proc, one needs to flush them from global
3098 * proc (proc_mnt) and from all the namespaces' procs this task was seen
3099 * in. This call is supposed to do all of this job.
3100 *
3101 * Looks in the dcache for
3102 * /proc/@pid
3103 * /proc/@tgid/task/@pid
3104 * if either directory is present flushes it and all of it'ts children
3105 * from the dcache.
3106 *
3107 * It is safe and reasonable to cache /proc entries for a task until
3108 * that task exits. After that they just clog up the dcache with
3109 * useless entries, possibly causing useful dcache entries to be
3110 * flushed instead. This routine is proved to flush those useless
3111 * dcache entries at process exit time.
3112 *
3113 * NOTE: This routine is just an optimization so it does not guarantee
3114 * that no dcache entries will exist at process exit time it
3115 * just makes it very unlikely that any will persist.
3116 */
3117
3118 void proc_flush_task(struct task_struct *task)
3119 {
3120 int i;
3121 struct pid *pid, *tgid;
3122 struct upid *upid;
3123
3124 pid = task_pid(task);
3125 tgid = task_tgid(task);
3126
3127 for (i = 0; i <= pid->level; i++) {
3128 upid = &pid->numbers[i];
3129 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
3130 tgid->numbers[i].nr);
3131 }
3132 }
3133
3134 static int proc_pid_instantiate(struct inode *dir,
3135 struct dentry * dentry,
3136 struct task_struct *task, const void *ptr)
3137 {
3138 struct inode *inode;
3139
3140 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
3141 if (!inode)
3142 goto out;
3143
3144 inode->i_op = &proc_tgid_base_inode_operations;
3145 inode->i_fop = &proc_tgid_base_operations;
3146 inode->i_flags|=S_IMMUTABLE;
3147
3148 set_nlink(inode, nlink_tgid);
3149
3150 d_set_d_op(dentry, &pid_dentry_operations);
3151
3152 d_add(dentry, inode);
3153 /* Close the race of the process dying before we return the dentry */
3154 if (pid_revalidate(dentry, 0))
3155 return 0;
3156 out:
3157 return -ENOENT;
3158 }
3159
3160 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3161 {
3162 int result = -ENOENT;
3163 struct task_struct *task;
3164 unsigned tgid;
3165 struct pid_namespace *ns;
3166
3167 tgid = name_to_int(&dentry->d_name);
3168 if (tgid == ~0U)
3169 goto out;
3170
3171 ns = dentry->d_sb->s_fs_info;
3172 rcu_read_lock();
3173 task = find_task_by_pid_ns(tgid, ns);
3174 if (task)
3175 get_task_struct(task);
3176 rcu_read_unlock();
3177 if (!task)
3178 goto out;
3179
3180 result = proc_pid_instantiate(dir, dentry, task, NULL);
3181 put_task_struct(task);
3182 out:
3183 return ERR_PTR(result);
3184 }
3185
3186 /*
3187 * Find the first task with tgid >= tgid
3188 *
3189 */
3190 struct tgid_iter {
3191 unsigned int tgid;
3192 struct task_struct *task;
3193 };
3194 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3195 {
3196 struct pid *pid;
3197
3198 if (iter.task)
3199 put_task_struct(iter.task);
3200 rcu_read_lock();
3201 retry:
3202 iter.task = NULL;
3203 pid = find_ge_pid(iter.tgid, ns);
3204 if (pid) {
3205 iter.tgid = pid_nr_ns(pid, ns);
3206 iter.task = pid_task(pid, PIDTYPE_PID);
3207 /* What we to know is if the pid we have find is the
3208 * pid of a thread_group_leader. Testing for task
3209 * being a thread_group_leader is the obvious thing
3210 * todo but there is a window when it fails, due to
3211 * the pid transfer logic in de_thread.
3212 *
3213 * So we perform the straight forward test of seeing
3214 * if the pid we have found is the pid of a thread
3215 * group leader, and don't worry if the task we have
3216 * found doesn't happen to be a thread group leader.
3217 * As we don't care in the case of readdir.
3218 */
3219 if (!iter.task || !has_group_leader_pid(iter.task)) {
3220 iter.tgid += 1;
3221 goto retry;
3222 }
3223 get_task_struct(iter.task);
3224 }
3225 rcu_read_unlock();
3226 return iter;
3227 }
3228
3229 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
3230
3231 /* for the /proc/ directory itself, after non-process stuff has been done */
3232 int proc_pid_readdir(struct file *file, struct dir_context *ctx)
3233 {
3234 struct tgid_iter iter;
3235 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info;
3236 loff_t pos = ctx->pos;
3237
3238 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
3239 return 0;
3240
3241 if (pos == TGID_OFFSET - 2) {
3242 struct inode *inode = d_inode(ns->proc_self);
3243 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
3244 return 0;
3245 ctx->pos = pos = pos + 1;
3246 }
3247 if (pos == TGID_OFFSET - 1) {
3248 struct inode *inode = d_inode(ns->proc_thread_self);
3249 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3250 return 0;
3251 ctx->pos = pos = pos + 1;
3252 }
3253 iter.tgid = pos - TGID_OFFSET;
3254 iter.task = NULL;
3255 for (iter = next_tgid(ns, iter);
3256 iter.task;
3257 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3258 char name[10 + 1];
3259 int len;
3260
3261 cond_resched();
3262 if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE))
3263 continue;
3264
3265 len = snprintf(name, sizeof(name), "%u", iter.tgid);
3266 ctx->pos = iter.tgid + TGID_OFFSET;
3267 if (!proc_fill_cache(file, ctx, name, len,
3268 proc_pid_instantiate, iter.task, NULL)) {
3269 put_task_struct(iter.task);
3270 return 0;
3271 }
3272 }
3273 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
3274 return 0;
3275 }
3276
3277 /*
3278 * proc_tid_comm_permission is a special permission function exclusively
3279 * used for the node /proc/<pid>/task/<tid>/comm.
3280 * It bypasses generic permission checks in the case where a task of the same
3281 * task group attempts to access the node.
3282 * The rationale behind this is that glibc and bionic access this node for
3283 * cross thread naming (pthread_set/getname_np(!self)). However, if
3284 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3285 * which locks out the cross thread naming implementation.
3286 * This function makes sure that the node is always accessible for members of
3287 * same thread group.
3288 */
3289 static int proc_tid_comm_permission(struct inode *inode, int mask)
3290 {
3291 bool is_same_tgroup;
3292 struct task_struct *task;
3293
3294 task = get_proc_task(inode);
3295 if (!task)
3296 return -ESRCH;
3297 is_same_tgroup = same_thread_group(current, task);
3298 put_task_struct(task);
3299
3300 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3301 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3302 * read or written by the members of the corresponding
3303 * thread group.
3304 */
3305 return 0;
3306 }
3307
3308 return generic_permission(inode, mask);
3309 }
3310
3311 static const struct inode_operations proc_tid_comm_inode_operations = {
3312 .permission = proc_tid_comm_permission,
3313 };
3314
3315 /*
3316 * Tasks
3317 */
3318 static const struct pid_entry tid_base_stuff[] = {
3319 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3320 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3321 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3322 #ifdef CONFIG_NET
3323 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3324 #endif
3325 REG("environ", S_IRUSR, proc_environ_operations),
3326 REG("auxv", S_IRUSR, proc_auxv_operations),
3327 ONE("status", S_IRUGO, proc_pid_status),
3328 ONE("personality", S_IRUSR, proc_pid_personality),
3329 ONE("limits", S_IRUGO, proc_pid_limits),
3330 #ifdef CONFIG_SCHED_DEBUG
3331 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3332 #endif
3333 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3334 &proc_tid_comm_inode_operations,
3335 &proc_pid_set_comm_operations, {}),
3336 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3337 ONE("syscall", S_IRUSR, proc_pid_syscall),
3338 #endif
3339 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3340 ONE("stat", S_IRUGO, proc_tid_stat),
3341 ONE("statm", S_IRUGO, proc_pid_statm),
3342 REG("maps", S_IRUGO, proc_tid_maps_operations),
3343 #ifdef CONFIG_PROC_CHILDREN
3344 REG("children", S_IRUGO, proc_tid_children_operations),
3345 #endif
3346 #ifdef CONFIG_NUMA
3347 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
3348 #endif
3349 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3350 LNK("cwd", proc_cwd_link),
3351 LNK("root", proc_root_link),
3352 LNK("exe", proc_exe_link),
3353 REG("mounts", S_IRUGO, proc_mounts_operations),
3354 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3355 #ifdef CONFIG_PROC_PAGE_MONITOR
3356 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3357 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
3358 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3359 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3360 #endif
3361 #ifdef CONFIG_SECURITY
3362 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3363 #endif
3364 #ifdef CONFIG_KALLSYMS
3365 ONE("wchan", S_IRUGO, proc_pid_wchan),
3366 #endif
3367 #ifdef CONFIG_STACKTRACE
3368 ONE("stack", S_IRUSR, proc_pid_stack),
3369 #endif
3370 #ifdef CONFIG_SCHED_INFO
3371 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3372 #endif
3373 #ifdef CONFIG_LATENCYTOP
3374 REG("latency", S_IRUGO, proc_lstats_operations),
3375 #endif
3376 #ifdef CONFIG_PROC_PID_CPUSET
3377 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3378 #endif
3379 #ifdef CONFIG_CGROUPS
3380 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3381 #endif
3382 ONE("oom_score", S_IRUGO, proc_oom_score),
3383 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3384 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3385 #ifdef CONFIG_AUDITSYSCALL
3386 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3387 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3388 #endif
3389 #ifdef CONFIG_FAULT_INJECTION
3390 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3391 REG("fail-nth", 0644, proc_fail_nth_operations),
3392 #endif
3393 #ifdef CONFIG_TASK_IO_ACCOUNTING
3394 ONE("io", S_IRUSR, proc_tid_io_accounting),
3395 #endif
3396 #ifdef CONFIG_HARDWALL
3397 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
3398 #endif
3399 #ifdef CONFIG_USER_NS
3400 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3401 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3402 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3403 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3404 #endif
3405 #ifdef CONFIG_LIVEPATCH
3406 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3407 #endif
3408 };
3409
3410 static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
3411 {
3412 return proc_pident_readdir(file, ctx,
3413 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3414 }
3415
3416 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3417 {
3418 return proc_pident_lookup(dir, dentry,
3419 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3420 }
3421
3422 static const struct file_operations proc_tid_base_operations = {
3423 .read = generic_read_dir,
3424 .iterate_shared = proc_tid_base_readdir,
3425 .llseek = generic_file_llseek,
3426 };
3427
3428 static const struct inode_operations proc_tid_base_inode_operations = {
3429 .lookup = proc_tid_base_lookup,
3430 .getattr = pid_getattr,
3431 .setattr = proc_setattr,
3432 };
3433
3434 static int proc_task_instantiate(struct inode *dir,
3435 struct dentry *dentry, struct task_struct *task, const void *ptr)
3436 {
3437 struct inode *inode;
3438 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
3439
3440 if (!inode)
3441 goto out;
3442 inode->i_op = &proc_tid_base_inode_operations;
3443 inode->i_fop = &proc_tid_base_operations;
3444 inode->i_flags|=S_IMMUTABLE;
3445
3446 set_nlink(inode, nlink_tid);
3447
3448 d_set_d_op(dentry, &pid_dentry_operations);
3449
3450 d_add(dentry, inode);
3451 /* Close the race of the process dying before we return the dentry */
3452 if (pid_revalidate(dentry, 0))
3453 return 0;
3454 out:
3455 return -ENOENT;
3456 }
3457
3458 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3459 {
3460 int result = -ENOENT;
3461 struct task_struct *task;
3462 struct task_struct *leader = get_proc_task(dir);
3463 unsigned tid;
3464 struct pid_namespace *ns;
3465
3466 if (!leader)
3467 goto out_no_task;
3468
3469 tid = name_to_int(&dentry->d_name);
3470 if (tid == ~0U)
3471 goto out;
3472
3473 ns = dentry->d_sb->s_fs_info;
3474 rcu_read_lock();
3475 task = find_task_by_pid_ns(tid, ns);
3476 if (task)
3477 get_task_struct(task);
3478 rcu_read_unlock();
3479 if (!task)
3480 goto out;
3481 if (!same_thread_group(leader, task))
3482 goto out_drop_task;
3483
3484 result = proc_task_instantiate(dir, dentry, task, NULL);
3485 out_drop_task:
3486 put_task_struct(task);
3487 out:
3488 put_task_struct(leader);
3489 out_no_task:
3490 return ERR_PTR(result);
3491 }
3492
3493 /*
3494 * Find the first tid of a thread group to return to user space.
3495 *
3496 * Usually this is just the thread group leader, but if the users
3497 * buffer was too small or there was a seek into the middle of the
3498 * directory we have more work todo.
3499 *
3500 * In the case of a short read we start with find_task_by_pid.
3501 *
3502 * In the case of a seek we start with the leader and walk nr
3503 * threads past it.
3504 */
3505 static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3506 struct pid_namespace *ns)
3507 {
3508 struct task_struct *pos, *task;
3509 unsigned long nr = f_pos;
3510
3511 if (nr != f_pos) /* 32bit overflow? */
3512 return NULL;
3513
3514 rcu_read_lock();
3515 task = pid_task(pid, PIDTYPE_PID);
3516 if (!task)
3517 goto fail;
3518
3519 /* Attempt to start with the tid of a thread */
3520 if (tid && nr) {
3521 pos = find_task_by_pid_ns(tid, ns);
3522 if (pos && same_thread_group(pos, task))
3523 goto found;
3524 }
3525
3526 /* If nr exceeds the number of threads there is nothing todo */
3527 if (nr >= get_nr_threads(task))
3528 goto fail;
3529
3530 /* If we haven't found our starting place yet start
3531 * with the leader and walk nr threads forward.
3532 */
3533 pos = task = task->group_leader;
3534 do {
3535 if (!nr--)
3536 goto found;
3537 } while_each_thread(task, pos);
3538 fail:
3539 pos = NULL;
3540 goto out;
3541 found:
3542 get_task_struct(pos);
3543 out:
3544 rcu_read_unlock();
3545 return pos;
3546 }
3547
3548 /*
3549 * Find the next thread in the thread list.
3550 * Return NULL if there is an error or no next thread.
3551 *
3552 * The reference to the input task_struct is released.
3553 */
3554 static struct task_struct *next_tid(struct task_struct *start)
3555 {
3556 struct task_struct *pos = NULL;
3557 rcu_read_lock();
3558 if (pid_alive(start)) {
3559 pos = next_thread(start);
3560 if (thread_group_leader(pos))
3561 pos = NULL;
3562 else
3563 get_task_struct(pos);
3564 }
3565 rcu_read_unlock();
3566 put_task_struct(start);
3567 return pos;
3568 }
3569
3570 /* for the /proc/TGID/task/ directories */
3571 static int proc_task_readdir(struct file *file, struct dir_context *ctx)
3572 {
3573 struct inode *inode = file_inode(file);
3574 struct task_struct *task;
3575 struct pid_namespace *ns;
3576 int tid;
3577
3578 if (proc_inode_is_dead(inode))
3579 return -ENOENT;
3580
3581 if (!dir_emit_dots(file, ctx))
3582 return 0;
3583
3584 /* f_version caches the tgid value that the last readdir call couldn't
3585 * return. lseek aka telldir automagically resets f_version to 0.
3586 */
3587 ns = inode->i_sb->s_fs_info;
3588 tid = (int)file->f_version;
3589 file->f_version = 0;
3590 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
3591 task;
3592 task = next_tid(task), ctx->pos++) {
3593 char name[10 + 1];
3594 int len;
3595 tid = task_pid_nr_ns(task, ns);
3596 len = snprintf(name, sizeof(name), "%u", tid);
3597 if (!proc_fill_cache(file, ctx, name, len,
3598 proc_task_instantiate, task, NULL)) {
3599 /* returning this tgid failed, save it as the first
3600 * pid for the next readir call */
3601 file->f_version = (u64)tid;
3602 put_task_struct(task);
3603 break;
3604 }
3605 }
3606
3607 return 0;
3608 }
3609
3610 static int proc_task_getattr(const struct path *path, struct kstat *stat,
3611 u32 request_mask, unsigned int query_flags)
3612 {
3613 struct inode *inode = d_inode(path->dentry);
3614 struct task_struct *p = get_proc_task(inode);
3615 generic_fillattr(inode, stat);
3616
3617 if (p) {
3618 stat->nlink += get_nr_threads(p);
3619 put_task_struct(p);
3620 }
3621
3622 return 0;
3623 }
3624
3625 static const struct inode_operations proc_task_inode_operations = {
3626 .lookup = proc_task_lookup,
3627 .getattr = proc_task_getattr,
3628 .setattr = proc_setattr,
3629 .permission = proc_pid_permission,
3630 };
3631
3632 static const struct file_operations proc_task_operations = {
3633 .read = generic_read_dir,
3634 .iterate_shared = proc_task_readdir,
3635 .llseek = generic_file_llseek,
3636 };
3637
3638 void __init set_proc_pid_nlink(void)
3639 {
3640 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3641 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3642 }
CRIS linux kernel tree