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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/generic-radix-tree.h>
63#include <linux/string.h>
64#include <linux/seq_file.h>
65#include <linux/namei.h>
66#include <linux/mnt_namespace.h>
67#include <linux/mm.h>
68#include <linux/swap.h>
69#include <linux/rcupdate.h>
70#include <linux/kallsyms.h>
71#include <linux/stacktrace.h>
72#include <linux/resource.h>
73#include <linux/module.h>
74#include <linux/mount.h>
75#include <linux/security.h>
76#include <linux/ptrace.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/posix-timers.h>
96#include <linux/time_namespace.h>
97#include <linux/resctrl.h>
98#include <linux/cn_proc.h>
99#include <trace/events/oom.h>
100#include "internal.h"
101#include "fd.h"
102
103#include "../../lib/kstrtox.h"
104
105/* NOTE:
106 * Implementing inode permission operations in /proc is almost
107 * certainly an error. Permission checks need to happen during
108 * each system call not at open time. The reason is that most of
109 * what we wish to check for permissions in /proc varies at runtime.
110 *
111 * The classic example of a problem is opening file descriptors
112 * in /proc for a task before it execs a suid executable.
113 */
114
115static u8 nlink_tid __ro_after_init;
116static u8 nlink_tgid __ro_after_init;
117
118struct pid_entry {
119 const char *name;
120 unsigned int len;
121 umode_t mode;
122 const struct inode_operations *iop;
123 const struct file_operations *fop;
124 union proc_op op;
125};
126
127#define NOD(NAME, MODE, IOP, FOP, OP) { \
128 .name = (NAME), \
129 .len = sizeof(NAME) - 1, \
130 .mode = MODE, \
131 .iop = IOP, \
132 .fop = FOP, \
133 .op = OP, \
134}
135
136#define DIR(NAME, MODE, iops, fops) \
137 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
138#define LNK(NAME, get_link) \
139 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
140 &proc_pid_link_inode_operations, NULL, \
141 { .proc_get_link = get_link } )
142#define REG(NAME, MODE, fops) \
143 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
144#define ONE(NAME, MODE, show) \
145 NOD(NAME, (S_IFREG|(MODE)), \
146 NULL, &proc_single_file_operations, \
147 { .proc_show = show } )
148#define ATTR(LSM, NAME, MODE) \
149 NOD(NAME, (S_IFREG|(MODE)), \
150 NULL, &proc_pid_attr_operations, \
151 { .lsm = LSM })
152
153/*
154 * Count the number of hardlinks for the pid_entry table, excluding the .
155 * and .. links.
156 */
157static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,
158 unsigned int n)
159{
160 unsigned int i;
161 unsigned int count;
162
163 count = 2;
164 for (i = 0; i < n; ++i) {
165 if (S_ISDIR(entries[i].mode))
166 ++count;
167 }
168
169 return count;
170}
171
172static int get_task_root(struct task_struct *task, struct path *root)
173{
174 int result = -ENOENT;
175
176 task_lock(task);
177 if (task->fs) {
178 get_fs_root(task->fs, root);
179 result = 0;
180 }
181 task_unlock(task);
182 return result;
183}
184
185static int proc_cwd_link(struct dentry *dentry, struct path *path)
186{
187 struct task_struct *task = get_proc_task(d_inode(dentry));
188 int result = -ENOENT;
189
190 if (task) {
191 task_lock(task);
192 if (task->fs) {
193 get_fs_pwd(task->fs, path);
194 result = 0;
195 }
196 task_unlock(task);
197 put_task_struct(task);
198 }
199 return result;
200}
201
202static int proc_root_link(struct dentry *dentry, struct path *path)
203{
204 struct task_struct *task = get_proc_task(d_inode(dentry));
205 int result = -ENOENT;
206
207 if (task) {
208 result = get_task_root(task, path);
209 put_task_struct(task);
210 }
211 return result;
212}
213
214/*
215 * If the user used setproctitle(), we just get the string from
216 * user space at arg_start, and limit it to a maximum of one page.
217 */
218static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf,
219 size_t count, unsigned long pos,
220 unsigned long arg_start)
221{
222 char *page;
223 int ret, got;
224
225 if (pos >= PAGE_SIZE)
226 return 0;
227
228 page = (char *)__get_free_page(GFP_KERNEL);
229 if (!page)
230 return -ENOMEM;
231
232 ret = 0;
233 got = access_remote_vm(mm, arg_start, page, PAGE_SIZE, FOLL_ANON);
234 if (got > 0) {
235 int len = strnlen(page, got);
236
237 /* Include the NUL character if it was found */
238 if (len < got)
239 len++;
240
241 if (len > pos) {
242 len -= pos;
243 if (len > count)
244 len = count;
245 len -= copy_to_user(buf, page+pos, len);
246 if (!len)
247 len = -EFAULT;
248 ret = len;
249 }
250 }
251 free_page((unsigned long)page);
252 return ret;
253}
254
255static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf,
256 size_t count, loff_t *ppos)
257{
258 unsigned long arg_start, arg_end, env_start, env_end;
259 unsigned long pos, len;
260 char *page, c;
261
262 /* Check if process spawned far enough to have cmdline. */
263 if (!mm->env_end)
264 return 0;
265
266 spin_lock(&mm->arg_lock);
267 arg_start = mm->arg_start;
268 arg_end = mm->arg_end;
269 env_start = mm->env_start;
270 env_end = mm->env_end;
271 spin_unlock(&mm->arg_lock);
272
273 if (arg_start >= arg_end)
274 return 0;
275
276 /*
277 * We allow setproctitle() to overwrite the argument
278 * strings, and overflow past the original end. But
279 * only when it overflows into the environment area.
280 */
281 if (env_start != arg_end || env_end < env_start)
282 env_start = env_end = arg_end;
283 len = env_end - arg_start;
284
285 /* We're not going to care if "*ppos" has high bits set */
286 pos = *ppos;
287 if (pos >= len)
288 return 0;
289 if (count > len - pos)
290 count = len - pos;
291 if (!count)
292 return 0;
293
294 /*
295 * Magical special case: if the argv[] end byte is not
296 * zero, the user has overwritten it with setproctitle(3).
297 *
298 * Possible future enhancement: do this only once when
299 * pos is 0, and set a flag in the 'struct file'.
300 */
301 if (access_remote_vm(mm, arg_end-1, &c, 1, FOLL_ANON) == 1 && c)
302 return get_mm_proctitle(mm, buf, count, pos, arg_start);
303
304 /*
305 * For the non-setproctitle() case we limit things strictly
306 * to the [arg_start, arg_end[ range.
307 */
308 pos += arg_start;
309 if (pos < arg_start || pos >= arg_end)
310 return 0;
311 if (count > arg_end - pos)
312 count = arg_end - pos;
313
314 page = (char *)__get_free_page(GFP_KERNEL);
315 if (!page)
316 return -ENOMEM;
317
318 len = 0;
319 while (count) {
320 int got;
321 size_t size = min_t(size_t, PAGE_SIZE, count);
322
323 got = access_remote_vm(mm, pos, page, size, FOLL_ANON);
324 if (got <= 0)
325 break;
326 got -= copy_to_user(buf, page, got);
327 if (unlikely(!got)) {
328 if (!len)
329 len = -EFAULT;
330 break;
331 }
332 pos += got;
333 buf += got;
334 len += got;
335 count -= got;
336 }
337
338 free_page((unsigned long)page);
339 return len;
340}
341
342static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf,
343 size_t count, loff_t *pos)
344{
345 struct mm_struct *mm;
346 ssize_t ret;
347
348 mm = get_task_mm(tsk);
349 if (!mm)
350 return 0;
351
352 ret = get_mm_cmdline(mm, buf, count, pos);
353 mmput(mm);
354 return ret;
355}
356
357static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
358 size_t count, loff_t *pos)
359{
360 struct task_struct *tsk;
361 ssize_t ret;
362
363 BUG_ON(*pos < 0);
364
365 tsk = get_proc_task(file_inode(file));
366 if (!tsk)
367 return -ESRCH;
368 ret = get_task_cmdline(tsk, buf, count, pos);
369 put_task_struct(tsk);
370 if (ret > 0)
371 *pos += ret;
372 return ret;
373}
374
375static const struct file_operations proc_pid_cmdline_ops = {
376 .read = proc_pid_cmdline_read,
377 .llseek = generic_file_llseek,
378};
379
380#ifdef CONFIG_KALLSYMS
381/*
382 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
383 * Returns the resolved symbol. If that fails, simply return the address.
384 */
385static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
386 struct pid *pid, struct task_struct *task)
387{
388 unsigned long wchan;
389 char symname[KSYM_NAME_LEN];
390
391 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
392 goto print0;
393
394 wchan = get_wchan(task);
395 if (wchan && !lookup_symbol_name(wchan, symname)) {
396 seq_puts(m, symname);
397 return 0;
398 }
399
400print0:
401 seq_putc(m, '0');
402 return 0;
403}
404#endif /* CONFIG_KALLSYMS */
405
406static int lock_trace(struct task_struct *task)
407{
408 int err = down_read_killable(&task->signal->exec_update_lock);
409 if (err)
410 return err;
411 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
412 up_read(&task->signal->exec_update_lock);
413 return -EPERM;
414 }
415 return 0;
416}
417
418static void unlock_trace(struct task_struct *task)
419{
420 up_read(&task->signal->exec_update_lock);
421}
422
423#ifdef CONFIG_STACKTRACE
424
425#define MAX_STACK_TRACE_DEPTH 64
426
427static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
428 struct pid *pid, struct task_struct *task)
429{
430 unsigned long *entries;
431 int err;
432
433 /*
434 * The ability to racily run the kernel stack unwinder on a running task
435 * and then observe the unwinder output is scary; while it is useful for
436 * debugging kernel issues, it can also allow an attacker to leak kernel
437 * stack contents.
438 * Doing this in a manner that is at least safe from races would require
439 * some work to ensure that the remote task can not be scheduled; and
440 * even then, this would still expose the unwinder as local attack
441 * surface.
442 * Therefore, this interface is restricted to root.
443 */
444 if (!file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN))
445 return -EACCES;
446
447 entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries),
448 GFP_KERNEL);
449 if (!entries)
450 return -ENOMEM;
451
452 err = lock_trace(task);
453 if (!err) {
454 unsigned int i, nr_entries;
455
456 nr_entries = stack_trace_save_tsk(task, entries,
457 MAX_STACK_TRACE_DEPTH, 0);
458
459 for (i = 0; i < nr_entries; i++) {
460 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]);
461 }
462
463 unlock_trace(task);
464 }
465 kfree(entries);
466
467 return err;
468}
469#endif
470
471#ifdef CONFIG_SCHED_INFO
472/*
473 * Provides /proc/PID/schedstat
474 */
475static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
476 struct pid *pid, struct task_struct *task)
477{
478 if (unlikely(!sched_info_on()))
479 seq_puts(m, "0 0 0\n");
480 else
481 seq_printf(m, "%llu %llu %lu\n",
482 (unsigned long long)task->se.sum_exec_runtime,
483 (unsigned long long)task->sched_info.run_delay,
484 task->sched_info.pcount);
485
486 return 0;
487}
488#endif
489
490#ifdef CONFIG_LATENCYTOP
491static int lstats_show_proc(struct seq_file *m, void *v)
492{
493 int i;
494 struct inode *inode = m->private;
495 struct task_struct *task = get_proc_task(inode);
496
497 if (!task)
498 return -ESRCH;
499 seq_puts(m, "Latency Top version : v0.1\n");
500 for (i = 0; i < LT_SAVECOUNT; i++) {
501 struct latency_record *lr = &task->latency_record[i];
502 if (lr->backtrace[0]) {
503 int q;
504 seq_printf(m, "%i %li %li",
505 lr->count, lr->time, lr->max);
506 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
507 unsigned long bt = lr->backtrace[q];
508
509 if (!bt)
510 break;
511 seq_printf(m, " %ps", (void *)bt);
512 }
513 seq_putc(m, '\n');
514 }
515
516 }
517 put_task_struct(task);
518 return 0;
519}
520
521static int lstats_open(struct inode *inode, struct file *file)
522{
523 return single_open(file, lstats_show_proc, inode);
524}
525
526static ssize_t lstats_write(struct file *file, const char __user *buf,
527 size_t count, loff_t *offs)
528{
529 struct task_struct *task = get_proc_task(file_inode(file));
530
531 if (!task)
532 return -ESRCH;
533 clear_tsk_latency_tracing(task);
534 put_task_struct(task);
535
536 return count;
537}
538
539static const struct file_operations proc_lstats_operations = {
540 .open = lstats_open,
541 .read = seq_read,
542 .write = lstats_write,
543 .llseek = seq_lseek,
544 .release = single_release,
545};
546
547#endif
548
549static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
550 struct pid *pid, struct task_struct *task)
551{
552 unsigned long totalpages = totalram_pages() + total_swap_pages;
553 unsigned long points = 0;
554 long badness;
555
556 badness = oom_badness(task, totalpages);
557 /*
558 * Special case OOM_SCORE_ADJ_MIN for all others scale the
559 * badness value into [0, 2000] range which we have been
560 * exporting for a long time so userspace might depend on it.
561 */
562 if (badness != LONG_MIN)
563 points = (1000 + badness * 1000 / (long)totalpages) * 2 / 3;
564
565 seq_printf(m, "%lu\n", points);
566
567 return 0;
568}
569
570struct limit_names {
571 const char *name;
572 const char *unit;
573};
574
575static const struct limit_names lnames[RLIM_NLIMITS] = {
576 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
577 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
578 [RLIMIT_DATA] = {"Max data size", "bytes"},
579 [RLIMIT_STACK] = {"Max stack size", "bytes"},
580 [RLIMIT_CORE] = {"Max core file size", "bytes"},
581 [RLIMIT_RSS] = {"Max resident set", "bytes"},
582 [RLIMIT_NPROC] = {"Max processes", "processes"},
583 [RLIMIT_NOFILE] = {"Max open files", "files"},
584 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
585 [RLIMIT_AS] = {"Max address space", "bytes"},
586 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
587 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
588 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
589 [RLIMIT_NICE] = {"Max nice priority", NULL},
590 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
591 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
592};
593
594/* Display limits for a process */
595static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
596 struct pid *pid, struct task_struct *task)
597{
598 unsigned int i;
599 unsigned long flags;
600
601 struct rlimit rlim[RLIM_NLIMITS];
602
603 if (!lock_task_sighand(task, &flags))
604 return 0;
605 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
606 unlock_task_sighand(task, &flags);
607
608 /*
609 * print the file header
610 */
611 seq_puts(m, "Limit "
612 "Soft Limit "
613 "Hard Limit "
614 "Units \n");
615
616 for (i = 0; i < RLIM_NLIMITS; i++) {
617 if (rlim[i].rlim_cur == RLIM_INFINITY)
618 seq_printf(m, "%-25s %-20s ",
619 lnames[i].name, "unlimited");
620 else
621 seq_printf(m, "%-25s %-20lu ",
622 lnames[i].name, rlim[i].rlim_cur);
623
624 if (rlim[i].rlim_max == RLIM_INFINITY)
625 seq_printf(m, "%-20s ", "unlimited");
626 else
627 seq_printf(m, "%-20lu ", rlim[i].rlim_max);
628
629 if (lnames[i].unit)
630 seq_printf(m, "%-10s\n", lnames[i].unit);
631 else
632 seq_putc(m, '\n');
633 }
634
635 return 0;
636}
637
638#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
639static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
640 struct pid *pid, struct task_struct *task)
641{
642 struct syscall_info info;
643 u64 *args = &info.data.args[0];
644 int res;
645
646 res = lock_trace(task);
647 if (res)
648 return res;
649
650 if (task_current_syscall(task, &info))
651 seq_puts(m, "running\n");
652 else if (info.data.nr < 0)
653 seq_printf(m, "%d 0x%llx 0x%llx\n",
654 info.data.nr, info.sp, info.data.instruction_pointer);
655 else
656 seq_printf(m,
657 "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n",
658 info.data.nr,
659 args[0], args[1], args[2], args[3], args[4], args[5],
660 info.sp, info.data.instruction_pointer);
661 unlock_trace(task);
662
663 return 0;
664}
665#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
666
667/************************************************************************/
668/* Here the fs part begins */
669/************************************************************************/
670
671/* permission checks */
672static bool proc_fd_access_allowed(struct inode *inode)
673{
674 struct task_struct *task;
675 bool allowed = false;
676 /* Allow access to a task's file descriptors if it is us or we
677 * may use ptrace attach to the process and find out that
678 * information.
679 */
680 task = get_proc_task(inode);
681 if (task) {
682 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
683 put_task_struct(task);
684 }
685 return allowed;
686}
687
688int proc_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
689 struct iattr *attr)
690{
691 int error;
692 struct inode *inode = d_inode(dentry);
693
694 if (attr->ia_valid & ATTR_MODE)
695 return -EPERM;
696
697 error = setattr_prepare(&init_user_ns, dentry, attr);
698 if (error)
699 return error;
700
701 setattr_copy(&init_user_ns, inode, attr);
702 mark_inode_dirty(inode);
703 return 0;
704}
705
706/*
707 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
708 * or euid/egid (for hide_pid_min=2)?
709 */
710static bool has_pid_permissions(struct proc_fs_info *fs_info,
711 struct task_struct *task,
712 enum proc_hidepid hide_pid_min)
713{
714 /*
715 * If 'hidpid' mount option is set force a ptrace check,
716 * we indicate that we are using a filesystem syscall
717 * by passing PTRACE_MODE_READ_FSCREDS
718 */
719 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE)
720 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
721
722 if (fs_info->hide_pid < hide_pid_min)
723 return true;
724 if (in_group_p(fs_info->pid_gid))
725 return true;
726 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
727}
728
729
730static int proc_pid_permission(struct user_namespace *mnt_userns,
731 struct inode *inode, int mask)
732{
733 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
734 struct task_struct *task;
735 bool has_perms;
736
737 task = get_proc_task(inode);
738 if (!task)
739 return -ESRCH;
740 has_perms = has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS);
741 put_task_struct(task);
742
743 if (!has_perms) {
744 if (fs_info->hide_pid == HIDEPID_INVISIBLE) {
745 /*
746 * Let's make getdents(), stat(), and open()
747 * consistent with each other. If a process
748 * may not stat() a file, it shouldn't be seen
749 * in procfs at all.
750 */
751 return -ENOENT;
752 }
753
754 return -EPERM;
755 }
756 return generic_permission(&init_user_ns, inode, mask);
757}
758
759
760
761static const struct inode_operations proc_def_inode_operations = {
762 .setattr = proc_setattr,
763};
764
765static int proc_single_show(struct seq_file *m, void *v)
766{
767 struct inode *inode = m->private;
768 struct pid_namespace *ns = proc_pid_ns(inode->i_sb);
769 struct pid *pid = proc_pid(inode);
770 struct task_struct *task;
771 int ret;
772
773 task = get_pid_task(pid, PIDTYPE_PID);
774 if (!task)
775 return -ESRCH;
776
777 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
778
779 put_task_struct(task);
780 return ret;
781}
782
783static int proc_single_open(struct inode *inode, struct file *filp)
784{
785 return single_open(filp, proc_single_show, inode);
786}
787
788static const struct file_operations proc_single_file_operations = {
789 .open = proc_single_open,
790 .read = seq_read,
791 .llseek = seq_lseek,
792 .release = single_release,
793};
794
795
796struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
797{
798 struct task_struct *task = get_proc_task(inode);
799 struct mm_struct *mm = ERR_PTR(-ESRCH);
800
801 if (task) {
802 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
803 put_task_struct(task);
804
805 if (!IS_ERR_OR_NULL(mm)) {
806 /* ensure this mm_struct can't be freed */
807 mmgrab(mm);
808 /* but do not pin its memory */
809 mmput(mm);
810 }
811 }
812
813 return mm;
814}
815
816static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
817{
818 struct mm_struct *mm = proc_mem_open(inode, mode);
819
820 if (IS_ERR(mm))
821 return PTR_ERR(mm);
822
823 file->private_data = mm;
824 return 0;
825}
826
827static int mem_open(struct inode *inode, struct file *file)
828{
829 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
830
831 /* OK to pass negative loff_t, we can catch out-of-range */
832 file->f_mode |= FMODE_UNSIGNED_OFFSET;
833
834 return ret;
835}
836
837static ssize_t mem_rw(struct file *file, char __user *buf,
838 size_t count, loff_t *ppos, int write)
839{
840 struct mm_struct *mm = file->private_data;
841 unsigned long addr = *ppos;
842 ssize_t copied;
843 char *page;
844 unsigned int flags;
845
846 if (!mm)
847 return 0;
848
849 page = (char *)__get_free_page(GFP_KERNEL);
850 if (!page)
851 return -ENOMEM;
852
853 copied = 0;
854 if (!mmget_not_zero(mm))
855 goto free;
856
857 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0);
858
859 while (count > 0) {
860 size_t this_len = min_t(size_t, count, PAGE_SIZE);
861
862 if (write && copy_from_user(page, buf, this_len)) {
863 copied = -EFAULT;
864 break;
865 }
866
867 this_len = access_remote_vm(mm, addr, page, this_len, flags);
868 if (!this_len) {
869 if (!copied)
870 copied = -EIO;
871 break;
872 }
873
874 if (!write && copy_to_user(buf, page, this_len)) {
875 copied = -EFAULT;
876 break;
877 }
878
879 buf += this_len;
880 addr += this_len;
881 copied += this_len;
882 count -= this_len;
883 }
884 *ppos = addr;
885
886 mmput(mm);
887free:
888 free_page((unsigned long) page);
889 return copied;
890}
891
892static ssize_t mem_read(struct file *file, char __user *buf,
893 size_t count, loff_t *ppos)
894{
895 return mem_rw(file, buf, count, ppos, 0);
896}
897
898static ssize_t mem_write(struct file *file, const char __user *buf,
899 size_t count, loff_t *ppos)
900{
901 return mem_rw(file, (char __user*)buf, count, ppos, 1);
902}
903
904loff_t mem_lseek(struct file *file, loff_t offset, int orig)
905{
906 switch (orig) {
907 case 0:
908 file->f_pos = offset;
909 break;
910 case 1:
911 file->f_pos += offset;
912 break;
913 default:
914 return -EINVAL;
915 }
916 force_successful_syscall_return();
917 return file->f_pos;
918}
919
920static int mem_release(struct inode *inode, struct file *file)
921{
922 struct mm_struct *mm = file->private_data;
923 if (mm)
924 mmdrop(mm);
925 return 0;
926}
927
928static const struct file_operations proc_mem_operations = {
929 .llseek = mem_lseek,
930 .read = mem_read,
931 .write = mem_write,
932 .open = mem_open,
933 .release = mem_release,
934};
935
936static int environ_open(struct inode *inode, struct file *file)
937{
938 return __mem_open(inode, file, PTRACE_MODE_READ);
939}
940
941static ssize_t environ_read(struct file *file, char __user *buf,
942 size_t count, loff_t *ppos)
943{
944 char *page;
945 unsigned long src = *ppos;
946 int ret = 0;
947 struct mm_struct *mm = file->private_data;
948 unsigned long env_start, env_end;
949
950 /* Ensure the process spawned far enough to have an environment. */
951 if (!mm || !mm->env_end)
952 return 0;
953
954 page = (char *)__get_free_page(GFP_KERNEL);
955 if (!page)
956 return -ENOMEM;
957
958 ret = 0;
959 if (!mmget_not_zero(mm))
960 goto free;
961
962 spin_lock(&mm->arg_lock);
963 env_start = mm->env_start;
964 env_end = mm->env_end;
965 spin_unlock(&mm->arg_lock);
966
967 while (count > 0) {
968 size_t this_len, max_len;
969 int retval;
970
971 if (src >= (env_end - env_start))
972 break;
973
974 this_len = env_end - (env_start + src);
975
976 max_len = min_t(size_t, PAGE_SIZE, count);
977 this_len = min(max_len, this_len);
978
979 retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON);
980
981 if (retval <= 0) {
982 ret = retval;
983 break;
984 }
985
986 if (copy_to_user(buf, page, retval)) {
987 ret = -EFAULT;
988 break;
989 }
990
991 ret += retval;
992 src += retval;
993 buf += retval;
994 count -= retval;
995 }
996 *ppos = src;
997 mmput(mm);
998
999free:
1000 free_page((unsigned long) page);
1001 return ret;
1002}
1003
1004static const struct file_operations proc_environ_operations = {
1005 .open = environ_open,
1006 .read = environ_read,
1007 .llseek = generic_file_llseek,
1008 .release = mem_release,
1009};
1010
1011static int auxv_open(struct inode *inode, struct file *file)
1012{
1013 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
1014}
1015
1016static ssize_t auxv_read(struct file *file, char __user *buf,
1017 size_t count, loff_t *ppos)
1018{
1019 struct mm_struct *mm = file->private_data;
1020 unsigned int nwords = 0;
1021
1022 if (!mm)
1023 return 0;
1024 do {
1025 nwords += 2;
1026 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1027 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,
1028 nwords * sizeof(mm->saved_auxv[0]));
1029}
1030
1031static const struct file_operations proc_auxv_operations = {
1032 .open = auxv_open,
1033 .read = auxv_read,
1034 .llseek = generic_file_llseek,
1035 .release = mem_release,
1036};
1037
1038static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1039 loff_t *ppos)
1040{
1041 struct task_struct *task = get_proc_task(file_inode(file));
1042 char buffer[PROC_NUMBUF];
1043 int oom_adj = OOM_ADJUST_MIN;
1044 size_t len;
1045
1046 if (!task)
1047 return -ESRCH;
1048 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1049 oom_adj = OOM_ADJUST_MAX;
1050 else
1051 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1052 OOM_SCORE_ADJ_MAX;
1053 put_task_struct(task);
1054 if (oom_adj > OOM_ADJUST_MAX)
1055 oom_adj = OOM_ADJUST_MAX;
1056 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1057 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1058}
1059
1060static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
1061{
1062 struct mm_struct *mm = NULL;
1063 struct task_struct *task;
1064 int err = 0;
1065
1066 task = get_proc_task(file_inode(file));
1067 if (!task)
1068 return -ESRCH;
1069
1070 mutex_lock(&oom_adj_mutex);
1071 if (legacy) {
1072 if (oom_adj < task->signal->oom_score_adj &&
1073 !capable(CAP_SYS_RESOURCE)) {
1074 err = -EACCES;
1075 goto err_unlock;
1076 }
1077 /*
1078 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1079 * /proc/pid/oom_score_adj instead.
1080 */
1081 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1082 current->comm, task_pid_nr(current), task_pid_nr(task),
1083 task_pid_nr(task));
1084 } else {
1085 if ((short)oom_adj < task->signal->oom_score_adj_min &&
1086 !capable(CAP_SYS_RESOURCE)) {
1087 err = -EACCES;
1088 goto err_unlock;
1089 }
1090 }
1091
1092 /*
1093 * Make sure we will check other processes sharing the mm if this is
1094 * not vfrok which wants its own oom_score_adj.
1095 * pin the mm so it doesn't go away and get reused after task_unlock
1096 */
1097 if (!task->vfork_done) {
1098 struct task_struct *p = find_lock_task_mm(task);
1099
1100 if (p) {
1101 if (test_bit(MMF_MULTIPROCESS, &p->mm->flags)) {
1102 mm = p->mm;
1103 mmgrab(mm);
1104 }
1105 task_unlock(p);
1106 }
1107 }
1108
1109 task->signal->oom_score_adj = oom_adj;
1110 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1111 task->signal->oom_score_adj_min = (short)oom_adj;
1112 trace_oom_score_adj_update(task);
1113
1114 if (mm) {
1115 struct task_struct *p;
1116
1117 rcu_read_lock();
1118 for_each_process(p) {
1119 if (same_thread_group(task, p))
1120 continue;
1121
1122 /* do not touch kernel threads or the global init */
1123 if (p->flags & PF_KTHREAD || is_global_init(p))
1124 continue;
1125
1126 task_lock(p);
1127 if (!p->vfork_done && process_shares_mm(p, mm)) {
1128 p->signal->oom_score_adj = oom_adj;
1129 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1130 p->signal->oom_score_adj_min = (short)oom_adj;
1131 }
1132 task_unlock(p);
1133 }
1134 rcu_read_unlock();
1135 mmdrop(mm);
1136 }
1137err_unlock:
1138 mutex_unlock(&oom_adj_mutex);
1139 put_task_struct(task);
1140 return err;
1141}
1142
1143/*
1144 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1145 * kernels. The effective policy is defined by oom_score_adj, which has a
1146 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1147 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1148 * Processes that become oom disabled via oom_adj will still be oom disabled
1149 * with this implementation.
1150 *
1151 * oom_adj cannot be removed since existing userspace binaries use it.
1152 */
1153static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1154 size_t count, loff_t *ppos)
1155{
1156 char buffer[PROC_NUMBUF];
1157 int oom_adj;
1158 int err;
1159
1160 memset(buffer, 0, sizeof(buffer));
1161 if (count > sizeof(buffer) - 1)
1162 count = sizeof(buffer) - 1;
1163 if (copy_from_user(buffer, buf, count)) {
1164 err = -EFAULT;
1165 goto out;
1166 }
1167
1168 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1169 if (err)
1170 goto out;
1171 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1172 oom_adj != OOM_DISABLE) {
1173 err = -EINVAL;
1174 goto out;
1175 }
1176
1177 /*
1178 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1179 * value is always attainable.
1180 */
1181 if (oom_adj == OOM_ADJUST_MAX)
1182 oom_adj = OOM_SCORE_ADJ_MAX;
1183 else
1184 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1185
1186 err = __set_oom_adj(file, oom_adj, true);
1187out:
1188 return err < 0 ? err : count;
1189}
1190
1191static const struct file_operations proc_oom_adj_operations = {
1192 .read = oom_adj_read,
1193 .write = oom_adj_write,
1194 .llseek = generic_file_llseek,
1195};
1196
1197static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1198 size_t count, loff_t *ppos)
1199{
1200 struct task_struct *task = get_proc_task(file_inode(file));
1201 char buffer[PROC_NUMBUF];
1202 short oom_score_adj = OOM_SCORE_ADJ_MIN;
1203 size_t len;
1204
1205 if (!task)
1206 return -ESRCH;
1207 oom_score_adj = task->signal->oom_score_adj;
1208 put_task_struct(task);
1209 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
1210 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1211}
1212
1213static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1214 size_t count, loff_t *ppos)
1215{
1216 char buffer[PROC_NUMBUF];
1217 int oom_score_adj;
1218 int err;
1219
1220 memset(buffer, 0, sizeof(buffer));
1221 if (count > sizeof(buffer) - 1)
1222 count = sizeof(buffer) - 1;
1223 if (copy_from_user(buffer, buf, count)) {
1224 err = -EFAULT;
1225 goto out;
1226 }
1227
1228 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1229 if (err)
1230 goto out;
1231 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1232 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1233 err = -EINVAL;
1234 goto out;
1235 }
1236
1237 err = __set_oom_adj(file, oom_score_adj, false);
1238out:
1239 return err < 0 ? err : count;
1240}
1241
1242static const struct file_operations proc_oom_score_adj_operations = {
1243 .read = oom_score_adj_read,
1244 .write = oom_score_adj_write,
1245 .llseek = default_llseek,
1246};
1247
1248#ifdef CONFIG_AUDIT
1249#define TMPBUFLEN 11
1250static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1251 size_t count, loff_t *ppos)
1252{
1253 struct inode * inode = file_inode(file);
1254 struct task_struct *task = get_proc_task(inode);
1255 ssize_t length;
1256 char tmpbuf[TMPBUFLEN];
1257
1258 if (!task)
1259 return -ESRCH;
1260 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1261 from_kuid(file->f_cred->user_ns,
1262 audit_get_loginuid(task)));
1263 put_task_struct(task);
1264 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1265}
1266
1267static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1268 size_t count, loff_t *ppos)
1269{
1270 struct inode * inode = file_inode(file);
1271 uid_t loginuid;
1272 kuid_t kloginuid;
1273 int rv;
1274
1275 /* Don't let kthreads write their own loginuid */
1276 if (current->flags & PF_KTHREAD)
1277 return -EPERM;
1278
1279 rcu_read_lock();
1280 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1281 rcu_read_unlock();
1282 return -EPERM;
1283 }
1284 rcu_read_unlock();
1285
1286 if (*ppos != 0) {
1287 /* No partial writes. */
1288 return -EINVAL;
1289 }
1290
1291 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1292 if (rv < 0)
1293 return rv;
1294
1295 /* is userspace tring to explicitly UNSET the loginuid? */
1296 if (loginuid == AUDIT_UID_UNSET) {
1297 kloginuid = INVALID_UID;
1298 } else {
1299 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
1300 if (!uid_valid(kloginuid))
1301 return -EINVAL;
1302 }
1303
1304 rv = audit_set_loginuid(kloginuid);
1305 if (rv < 0)
1306 return rv;
1307 return count;
1308}
1309
1310static const struct file_operations proc_loginuid_operations = {
1311 .read = proc_loginuid_read,
1312 .write = proc_loginuid_write,
1313 .llseek = generic_file_llseek,
1314};
1315
1316static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1317 size_t count, loff_t *ppos)
1318{
1319 struct inode * inode = file_inode(file);
1320 struct task_struct *task = get_proc_task(inode);
1321 ssize_t length;
1322 char tmpbuf[TMPBUFLEN];
1323
1324 if (!task)
1325 return -ESRCH;
1326 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1327 audit_get_sessionid(task));
1328 put_task_struct(task);
1329 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1330}
1331
1332static const struct file_operations proc_sessionid_operations = {
1333 .read = proc_sessionid_read,
1334 .llseek = generic_file_llseek,
1335};
1336#endif
1337
1338#ifdef CONFIG_FAULT_INJECTION
1339static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1340 size_t count, loff_t *ppos)
1341{
1342 struct task_struct *task = get_proc_task(file_inode(file));
1343 char buffer[PROC_NUMBUF];
1344 size_t len;
1345 int make_it_fail;
1346
1347 if (!task)
1348 return -ESRCH;
1349 make_it_fail = task->make_it_fail;
1350 put_task_struct(task);
1351
1352 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1353
1354 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1355}
1356
1357static ssize_t proc_fault_inject_write(struct file * file,
1358 const char __user * buf, size_t count, loff_t *ppos)
1359{
1360 struct task_struct *task;
1361 char buffer[PROC_NUMBUF];
1362 int make_it_fail;
1363 int rv;
1364
1365 if (!capable(CAP_SYS_RESOURCE))
1366 return -EPERM;
1367 memset(buffer, 0, sizeof(buffer));
1368 if (count > sizeof(buffer) - 1)
1369 count = sizeof(buffer) - 1;
1370 if (copy_from_user(buffer, buf, count))
1371 return -EFAULT;
1372 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1373 if (rv < 0)
1374 return rv;
1375 if (make_it_fail < 0 || make_it_fail > 1)
1376 return -EINVAL;
1377
1378 task = get_proc_task(file_inode(file));
1379 if (!task)
1380 return -ESRCH;
1381 task->make_it_fail = make_it_fail;
1382 put_task_struct(task);
1383
1384 return count;
1385}
1386
1387static const struct file_operations proc_fault_inject_operations = {
1388 .read = proc_fault_inject_read,
1389 .write = proc_fault_inject_write,
1390 .llseek = generic_file_llseek,
1391};
1392
1393static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf,
1394 size_t count, loff_t *ppos)
1395{
1396 struct task_struct *task;
1397 int err;
1398 unsigned int n;
1399
1400 err = kstrtouint_from_user(buf, count, 0, &n);
1401 if (err)
1402 return err;
1403
1404 task = get_proc_task(file_inode(file));
1405 if (!task)
1406 return -ESRCH;
1407 task->fail_nth = n;
1408 put_task_struct(task);
1409
1410 return count;
1411}
1412
1413static ssize_t proc_fail_nth_read(struct file *file, char __user *buf,
1414 size_t count, loff_t *ppos)
1415{
1416 struct task_struct *task;
1417 char numbuf[PROC_NUMBUF];
1418 ssize_t len;
1419
1420 task = get_proc_task(file_inode(file));
1421 if (!task)
1422 return -ESRCH;
1423 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth);
1424 put_task_struct(task);
1425 return simple_read_from_buffer(buf, count, ppos, numbuf, len);
1426}
1427
1428static const struct file_operations proc_fail_nth_operations = {
1429 .read = proc_fail_nth_read,
1430 .write = proc_fail_nth_write,
1431};
1432#endif
1433
1434
1435#ifdef CONFIG_SCHED_DEBUG
1436/*
1437 * Print out various scheduling related per-task fields:
1438 */
1439static int sched_show(struct seq_file *m, void *v)
1440{
1441 struct inode *inode = m->private;
1442 struct pid_namespace *ns = proc_pid_ns(inode->i_sb);
1443 struct task_struct *p;
1444
1445 p = get_proc_task(inode);
1446 if (!p)
1447 return -ESRCH;
1448 proc_sched_show_task(p, ns, m);
1449
1450 put_task_struct(p);
1451
1452 return 0;
1453}
1454
1455static ssize_t
1456sched_write(struct file *file, const char __user *buf,
1457 size_t count, loff_t *offset)
1458{
1459 struct inode *inode = file_inode(file);
1460 struct task_struct *p;
1461
1462 p = get_proc_task(inode);
1463 if (!p)
1464 return -ESRCH;
1465 proc_sched_set_task(p);
1466
1467 put_task_struct(p);
1468
1469 return count;
1470}
1471
1472static int sched_open(struct inode *inode, struct file *filp)
1473{
1474 return single_open(filp, sched_show, inode);
1475}
1476
1477static const struct file_operations proc_pid_sched_operations = {
1478 .open = sched_open,
1479 .read = seq_read,
1480 .write = sched_write,
1481 .llseek = seq_lseek,
1482 .release = single_release,
1483};
1484
1485#endif
1486
1487#ifdef CONFIG_SCHED_AUTOGROUP
1488/*
1489 * Print out autogroup related information:
1490 */
1491static int sched_autogroup_show(struct seq_file *m, void *v)
1492{
1493 struct inode *inode = m->private;
1494 struct task_struct *p;
1495
1496 p = get_proc_task(inode);
1497 if (!p)
1498 return -ESRCH;
1499 proc_sched_autogroup_show_task(p, m);
1500
1501 put_task_struct(p);
1502
1503 return 0;
1504}
1505
1506static ssize_t
1507sched_autogroup_write(struct file *file, const char __user *buf,
1508 size_t count, loff_t *offset)
1509{
1510 struct inode *inode = file_inode(file);
1511 struct task_struct *p;
1512 char buffer[PROC_NUMBUF];
1513 int nice;
1514 int err;
1515
1516 memset(buffer, 0, sizeof(buffer));
1517 if (count > sizeof(buffer) - 1)
1518 count = sizeof(buffer) - 1;
1519 if (copy_from_user(buffer, buf, count))
1520 return -EFAULT;
1521
1522 err = kstrtoint(strstrip(buffer), 0, &nice);
1523 if (err < 0)
1524 return err;
1525
1526 p = get_proc_task(inode);
1527 if (!p)
1528 return -ESRCH;
1529
1530 err = proc_sched_autogroup_set_nice(p, nice);
1531 if (err)
1532 count = err;
1533
1534 put_task_struct(p);
1535
1536 return count;
1537}
1538
1539static int sched_autogroup_open(struct inode *inode, struct file *filp)
1540{
1541 int ret;
1542
1543 ret = single_open(filp, sched_autogroup_show, NULL);
1544 if (!ret) {
1545 struct seq_file *m = filp->private_data;
1546
1547 m->private = inode;
1548 }
1549 return ret;
1550}
1551
1552static const struct file_operations proc_pid_sched_autogroup_operations = {
1553 .open = sched_autogroup_open,
1554 .read = seq_read,
1555 .write = sched_autogroup_write,
1556 .llseek = seq_lseek,
1557 .release = single_release,
1558};
1559
1560#endif /* CONFIG_SCHED_AUTOGROUP */
1561
1562#ifdef CONFIG_TIME_NS
1563static int timens_offsets_show(struct seq_file *m, void *v)
1564{
1565 struct task_struct *p;
1566
1567 p = get_proc_task(file_inode(m->file));
1568 if (!p)
1569 return -ESRCH;
1570 proc_timens_show_offsets(p, m);
1571
1572 put_task_struct(p);
1573
1574 return 0;
1575}
1576
1577static ssize_t timens_offsets_write(struct file *file, const char __user *buf,
1578 size_t count, loff_t *ppos)
1579{
1580 struct inode *inode = file_inode(file);
1581 struct proc_timens_offset offsets[2];
1582 char *kbuf = NULL, *pos, *next_line;
1583 struct task_struct *p;
1584 int ret, noffsets;
1585
1586 /* Only allow < page size writes at the beginning of the file */
1587 if ((*ppos != 0) || (count >= PAGE_SIZE))
1588 return -EINVAL;
1589
1590 /* Slurp in the user data */
1591 kbuf = memdup_user_nul(buf, count);
1592 if (IS_ERR(kbuf))
1593 return PTR_ERR(kbuf);
1594
1595 /* Parse the user data */
1596 ret = -EINVAL;
1597 noffsets = 0;
1598 for (pos = kbuf; pos; pos = next_line) {
1599 struct proc_timens_offset *off = &offsets[noffsets];
1600 char clock[10];
1601 int err;
1602
1603 /* Find the end of line and ensure we don't look past it */
1604 next_line = strchr(pos, '\n');
1605 if (next_line) {
1606 *next_line = '\0';
1607 next_line++;
1608 if (*next_line == '\0')
1609 next_line = NULL;
1610 }
1611
1612 err = sscanf(pos, "%9s %lld %lu", clock,
1613 &off->val.tv_sec, &off->val.tv_nsec);
1614 if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC)
1615 goto out;
1616
1617 clock[sizeof(clock) - 1] = 0;
1618 if (strcmp(clock, "monotonic") == 0 ||
1619 strcmp(clock, __stringify(CLOCK_MONOTONIC)) == 0)
1620 off->clockid = CLOCK_MONOTONIC;
1621 else if (strcmp(clock, "boottime") == 0 ||
1622 strcmp(clock, __stringify(CLOCK_BOOTTIME)) == 0)
1623 off->clockid = CLOCK_BOOTTIME;
1624 else
1625 goto out;
1626
1627 noffsets++;
1628 if (noffsets == ARRAY_SIZE(offsets)) {
1629 if (next_line)
1630 count = next_line - kbuf;
1631 break;
1632 }
1633 }
1634
1635 ret = -ESRCH;
1636 p = get_proc_task(inode);
1637 if (!p)
1638 goto out;
1639 ret = proc_timens_set_offset(file, p, offsets, noffsets);
1640 put_task_struct(p);
1641 if (ret)
1642 goto out;
1643
1644 ret = count;
1645out:
1646 kfree(kbuf);
1647 return ret;
1648}
1649
1650static int timens_offsets_open(struct inode *inode, struct file *filp)
1651{
1652 return single_open(filp, timens_offsets_show, inode);
1653}
1654
1655static const struct file_operations proc_timens_offsets_operations = {
1656 .open = timens_offsets_open,
1657 .read = seq_read,
1658 .write = timens_offsets_write,
1659 .llseek = seq_lseek,
1660 .release = single_release,
1661};
1662#endif /* CONFIG_TIME_NS */
1663
1664static ssize_t comm_write(struct file *file, const char __user *buf,
1665 size_t count, loff_t *offset)
1666{
1667 struct inode *inode = file_inode(file);
1668 struct task_struct *p;
1669 char buffer[TASK_COMM_LEN];
1670 const size_t maxlen = sizeof(buffer) - 1;
1671
1672 memset(buffer, 0, sizeof(buffer));
1673 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
1674 return -EFAULT;
1675
1676 p = get_proc_task(inode);
1677 if (!p)
1678 return -ESRCH;
1679
1680 if (same_thread_group(current, p)) {
1681 set_task_comm(p, buffer);
1682 proc_comm_connector(p);
1683 }
1684 else
1685 count = -EINVAL;
1686
1687 put_task_struct(p);
1688
1689 return count;
1690}
1691
1692static int comm_show(struct seq_file *m, void *v)
1693{
1694 struct inode *inode = m->private;
1695 struct task_struct *p;
1696
1697 p = get_proc_task(inode);
1698 if (!p)
1699 return -ESRCH;
1700
1701 proc_task_name(m, p, false);
1702 seq_putc(m, '\n');
1703
1704 put_task_struct(p);
1705
1706 return 0;
1707}
1708
1709static int comm_open(struct inode *inode, struct file *filp)
1710{
1711 return single_open(filp, comm_show, inode);
1712}
1713
1714static const struct file_operations proc_pid_set_comm_operations = {
1715 .open = comm_open,
1716 .read = seq_read,
1717 .write = comm_write,
1718 .llseek = seq_lseek,
1719 .release = single_release,
1720};
1721
1722static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1723{
1724 struct task_struct *task;
1725 struct file *exe_file;
1726
1727 task = get_proc_task(d_inode(dentry));
1728 if (!task)
1729 return -ENOENT;
1730 exe_file = get_task_exe_file(task);
1731 put_task_struct(task);
1732 if (exe_file) {
1733 *exe_path = exe_file->f_path;
1734 path_get(&exe_file->f_path);
1735 fput(exe_file);
1736 return 0;
1737 } else
1738 return -ENOENT;
1739}
1740
1741static const char *proc_pid_get_link(struct dentry *dentry,
1742 struct inode *inode,
1743 struct delayed_call *done)
1744{
1745 struct path path;
1746 int error = -EACCES;
1747
1748 if (!dentry)
1749 return ERR_PTR(-ECHILD);
1750
1751 /* Are we allowed to snoop on the tasks file descriptors? */
1752 if (!proc_fd_access_allowed(inode))
1753 goto out;
1754
1755 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1756 if (error)
1757 goto out;
1758
1759 error = nd_jump_link(&path);
1760out:
1761 return ERR_PTR(error);
1762}
1763
1764static int do_proc_readlink(const struct path *path, char __user *buffer, int buflen)
1765{
1766 char *tmp = kmalloc(PATH_MAX, GFP_KERNEL);
1767 char *pathname;
1768 int len;
1769
1770 if (!tmp)
1771 return -ENOMEM;
1772
1773 pathname = d_path(path, tmp, PATH_MAX);
1774 len = PTR_ERR(pathname);
1775 if (IS_ERR(pathname))
1776 goto out;
1777 len = tmp + PATH_MAX - 1 - pathname;
1778
1779 if (len > buflen)
1780 len = buflen;
1781 if (copy_to_user(buffer, pathname, len))
1782 len = -EFAULT;
1783 out:
1784 kfree(tmp);
1785 return len;
1786}
1787
1788static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1789{
1790 int error = -EACCES;
1791 struct inode *inode = d_inode(dentry);
1792 struct path path;
1793
1794 /* Are we allowed to snoop on the tasks file descriptors? */
1795 if (!proc_fd_access_allowed(inode))
1796 goto out;
1797
1798 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1799 if (error)
1800 goto out;
1801
1802 error = do_proc_readlink(&path, buffer, buflen);
1803 path_put(&path);
1804out:
1805 return error;
1806}
1807
1808const struct inode_operations proc_pid_link_inode_operations = {
1809 .readlink = proc_pid_readlink,
1810 .get_link = proc_pid_get_link,
1811 .setattr = proc_setattr,
1812};
1813
1814
1815/* building an inode */
1816
1817void task_dump_owner(struct task_struct *task, umode_t mode,
1818 kuid_t *ruid, kgid_t *rgid)
1819{
1820 /* Depending on the state of dumpable compute who should own a
1821 * proc file for a task.
1822 */
1823 const struct cred *cred;
1824 kuid_t uid;
1825 kgid_t gid;
1826
1827 if (unlikely(task->flags & PF_KTHREAD)) {
1828 *ruid = GLOBAL_ROOT_UID;
1829 *rgid = GLOBAL_ROOT_GID;
1830 return;
1831 }
1832
1833 /* Default to the tasks effective ownership */
1834 rcu_read_lock();
1835 cred = __task_cred(task);
1836 uid = cred->euid;
1837 gid = cred->egid;
1838 rcu_read_unlock();
1839
1840 /*
1841 * Before the /proc/pid/status file was created the only way to read
1842 * the effective uid of a /process was to stat /proc/pid. Reading
1843 * /proc/pid/status is slow enough that procps and other packages
1844 * kept stating /proc/pid. To keep the rules in /proc simple I have
1845 * made this apply to all per process world readable and executable
1846 * directories.
1847 */
1848 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) {
1849 struct mm_struct *mm;
1850 task_lock(task);
1851 mm = task->mm;
1852 /* Make non-dumpable tasks owned by some root */
1853 if (mm) {
1854 if (get_dumpable(mm) != SUID_DUMP_USER) {
1855 struct user_namespace *user_ns = mm->user_ns;
1856
1857 uid = make_kuid(user_ns, 0);
1858 if (!uid_valid(uid))
1859 uid = GLOBAL_ROOT_UID;
1860
1861 gid = make_kgid(user_ns, 0);
1862 if (!gid_valid(gid))
1863 gid = GLOBAL_ROOT_GID;
1864 }
1865 } else {
1866 uid = GLOBAL_ROOT_UID;
1867 gid = GLOBAL_ROOT_GID;
1868 }
1869 task_unlock(task);
1870 }
1871 *ruid = uid;
1872 *rgid = gid;
1873}
1874
1875void proc_pid_evict_inode(struct proc_inode *ei)
1876{
1877 struct pid *pid = ei->pid;
1878
1879 if (S_ISDIR(ei->vfs_inode.i_mode)) {
1880 spin_lock(&pid->lock);
1881 hlist_del_init_rcu(&ei->sibling_inodes);
1882 spin_unlock(&pid->lock);
1883 }
1884
1885 put_pid(pid);
1886}
1887
1888struct inode *proc_pid_make_inode(struct super_block *sb,
1889 struct task_struct *task, umode_t mode)
1890{
1891 struct inode * inode;
1892 struct proc_inode *ei;
1893 struct pid *pid;
1894
1895 /* We need a new inode */
1896
1897 inode = new_inode(sb);
1898 if (!inode)
1899 goto out;
1900
1901 /* Common stuff */
1902 ei = PROC_I(inode);
1903 inode->i_mode = mode;
1904 inode->i_ino = get_next_ino();
1905 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
1906 inode->i_op = &proc_def_inode_operations;
1907
1908 /*
1909 * grab the reference to task.
1910 */
1911 pid = get_task_pid(task, PIDTYPE_PID);
1912 if (!pid)
1913 goto out_unlock;
1914
1915 /* Let the pid remember us for quick removal */
1916 ei->pid = pid;
1917
1918 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1919 security_task_to_inode(task, inode);
1920
1921out:
1922 return inode;
1923
1924out_unlock:
1925 iput(inode);
1926 return NULL;
1927}
1928
1929/*
1930 * Generating an inode and adding it into @pid->inodes, so that task will
1931 * invalidate inode's dentry before being released.
1932 *
1933 * This helper is used for creating dir-type entries under '/proc' and
1934 * '/proc/<tgid>/task'. Other entries(eg. fd, stat) under '/proc/<tgid>'
1935 * can be released by invalidating '/proc/<tgid>' dentry.
1936 * In theory, dentries under '/proc/<tgid>/task' can also be released by
1937 * invalidating '/proc/<tgid>' dentry, we reserve it to handle single
1938 * thread exiting situation: Any one of threads should invalidate its
1939 * '/proc/<tgid>/task/<pid>' dentry before released.
1940 */
1941static struct inode *proc_pid_make_base_inode(struct super_block *sb,
1942 struct task_struct *task, umode_t mode)
1943{
1944 struct inode *inode;
1945 struct proc_inode *ei;
1946 struct pid *pid;
1947
1948 inode = proc_pid_make_inode(sb, task, mode);
1949 if (!inode)
1950 return NULL;
1951
1952 /* Let proc_flush_pid find this directory inode */
1953 ei = PROC_I(inode);
1954 pid = ei->pid;
1955 spin_lock(&pid->lock);
1956 hlist_add_head_rcu(&ei->sibling_inodes, &pid->inodes);
1957 spin_unlock(&pid->lock);
1958
1959 return inode;
1960}
1961
1962int pid_getattr(struct user_namespace *mnt_userns, const struct path *path,
1963 struct kstat *stat, u32 request_mask, unsigned int query_flags)
1964{
1965 struct inode *inode = d_inode(path->dentry);
1966 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
1967 struct task_struct *task;
1968
1969 generic_fillattr(&init_user_ns, inode, stat);
1970
1971 stat->uid = GLOBAL_ROOT_UID;
1972 stat->gid = GLOBAL_ROOT_GID;
1973 rcu_read_lock();
1974 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1975 if (task) {
1976 if (!has_pid_permissions(fs_info, task, HIDEPID_INVISIBLE)) {
1977 rcu_read_unlock();
1978 /*
1979 * This doesn't prevent learning whether PID exists,
1980 * it only makes getattr() consistent with readdir().
1981 */
1982 return -ENOENT;
1983 }
1984 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid);
1985 }
1986 rcu_read_unlock();
1987 return 0;
1988}
1989
1990/* dentry stuff */
1991
1992/*
1993 * Set <pid>/... inode ownership (can change due to setuid(), etc.)
1994 */
1995void pid_update_inode(struct task_struct *task, struct inode *inode)
1996{
1997 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
1998
1999 inode->i_mode &= ~(S_ISUID | S_ISGID);
2000 security_task_to_inode(task, inode);
2001}
2002
2003/*
2004 * Rewrite the inode's ownerships here because the owning task may have
2005 * performed a setuid(), etc.
2006 *
2007 */
2008static int pid_revalidate(struct dentry *dentry, unsigned int flags)
2009{
2010 struct inode *inode;
2011 struct task_struct *task;
2012 int ret = 0;
2013
2014 rcu_read_lock();
2015 inode = d_inode_rcu(dentry);
2016 if (!inode)
2017 goto out;
2018 task = pid_task(proc_pid(inode), PIDTYPE_PID);
2019
2020 if (task) {
2021 pid_update_inode(task, inode);
2022 ret = 1;
2023 }
2024out:
2025 rcu_read_unlock();
2026 return ret;
2027}
2028
2029static inline bool proc_inode_is_dead(struct inode *inode)
2030{
2031 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
2032}
2033
2034int pid_delete_dentry(const struct dentry *dentry)
2035{
2036 /* Is the task we represent dead?
2037 * If so, then don't put the dentry on the lru list,
2038 * kill it immediately.
2039 */
2040 return proc_inode_is_dead(d_inode(dentry));
2041}
2042
2043const struct dentry_operations pid_dentry_operations =
2044{
2045 .d_revalidate = pid_revalidate,
2046 .d_delete = pid_delete_dentry,
2047};
2048
2049/* Lookups */
2050
2051/*
2052 * Fill a directory entry.
2053 *
2054 * If possible create the dcache entry and derive our inode number and
2055 * file type from dcache entry.
2056 *
2057 * Since all of the proc inode numbers are dynamically generated, the inode
2058 * numbers do not exist until the inode is cache. This means creating
2059 * the dcache entry in readdir is necessary to keep the inode numbers
2060 * reported by readdir in sync with the inode numbers reported
2061 * by stat.
2062 */
2063bool proc_fill_cache(struct file *file, struct dir_context *ctx,
2064 const char *name, unsigned int len,
2065 instantiate_t instantiate, struct task_struct *task, const void *ptr)
2066{
2067 struct dentry *child, *dir = file->f_path.dentry;
2068 struct qstr qname = QSTR_INIT(name, len);
2069 struct inode *inode;
2070 unsigned type = DT_UNKNOWN;
2071 ino_t ino = 1;
2072
2073 child = d_hash_and_lookup(dir, &qname);
2074 if (!child) {
2075 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
2076 child = d_alloc_parallel(dir, &qname, &wq);
2077 if (IS_ERR(child))
2078 goto end_instantiate;
2079 if (d_in_lookup(child)) {
2080 struct dentry *res;
2081 res = instantiate(child, task, ptr);
2082 d_lookup_done(child);
2083 if (unlikely(res)) {
2084 dput(child);
2085 child = res;
2086 if (IS_ERR(child))
2087 goto end_instantiate;
2088 }
2089 }
2090 }
2091 inode = d_inode(child);
2092 ino = inode->i_ino;
2093 type = inode->i_mode >> 12;
2094 dput(child);
2095end_instantiate:
2096 return dir_emit(ctx, name, len, ino, type);
2097}
2098
2099/*
2100 * dname_to_vma_addr - maps a dentry name into two unsigned longs
2101 * which represent vma start and end addresses.
2102 */
2103static int dname_to_vma_addr(struct dentry *dentry,
2104 unsigned long *start, unsigned long *end)
2105{
2106 const char *str = dentry->d_name.name;
2107 unsigned long long sval, eval;
2108 unsigned int len;
2109
2110 if (str[0] == '0' && str[1] != '-')
2111 return -EINVAL;
2112 len = _parse_integer(str, 16, &sval);
2113 if (len & KSTRTOX_OVERFLOW)
2114 return -EINVAL;
2115 if (sval != (unsigned long)sval)
2116 return -EINVAL;
2117 str += len;
2118
2119 if (*str != '-')
2120 return -EINVAL;
2121 str++;
2122
2123 if (str[0] == '0' && str[1])
2124 return -EINVAL;
2125 len = _parse_integer(str, 16, &eval);
2126 if (len & KSTRTOX_OVERFLOW)
2127 return -EINVAL;
2128 if (eval != (unsigned long)eval)
2129 return -EINVAL;
2130 str += len;
2131
2132 if (*str != '\0')
2133 return -EINVAL;
2134
2135 *start = sval;
2136 *end = eval;
2137
2138 return 0;
2139}
2140
2141static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
2142{
2143 unsigned long vm_start, vm_end;
2144 bool exact_vma_exists = false;
2145 struct mm_struct *mm = NULL;
2146 struct task_struct *task;
2147 struct inode *inode;
2148 int status = 0;
2149
2150 if (flags & LOOKUP_RCU)
2151 return -ECHILD;
2152
2153 inode = d_inode(dentry);
2154 task = get_proc_task(inode);
2155 if (!task)
2156 goto out_notask;
2157
2158 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
2159 if (IS_ERR_OR_NULL(mm))
2160 goto out;
2161
2162 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2163 status = mmap_read_lock_killable(mm);
2164 if (!status) {
2165 exact_vma_exists = !!find_exact_vma(mm, vm_start,
2166 vm_end);
2167 mmap_read_unlock(mm);
2168 }
2169 }
2170
2171 mmput(mm);
2172
2173 if (exact_vma_exists) {
2174 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
2175
2176 security_task_to_inode(task, inode);
2177 status = 1;
2178 }
2179
2180out:
2181 put_task_struct(task);
2182
2183out_notask:
2184 return status;
2185}
2186
2187static const struct dentry_operations tid_map_files_dentry_operations = {
2188 .d_revalidate = map_files_d_revalidate,
2189 .d_delete = pid_delete_dentry,
2190};
2191
2192static int map_files_get_link(struct dentry *dentry, struct path *path)
2193{
2194 unsigned long vm_start, vm_end;
2195 struct vm_area_struct *vma;
2196 struct task_struct *task;
2197 struct mm_struct *mm;
2198 int rc;
2199
2200 rc = -ENOENT;
2201 task = get_proc_task(d_inode(dentry));
2202 if (!task)
2203 goto out;
2204
2205 mm = get_task_mm(task);
2206 put_task_struct(task);
2207 if (!mm)
2208 goto out;
2209
2210 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2211 if (rc)
2212 goto out_mmput;
2213
2214 rc = mmap_read_lock_killable(mm);
2215 if (rc)
2216 goto out_mmput;
2217
2218 rc = -ENOENT;
2219 vma = find_exact_vma(mm, vm_start, vm_end);
2220 if (vma && vma->vm_file) {
2221 *path = vma->vm_file->f_path;
2222 path_get(path);
2223 rc = 0;
2224 }
2225 mmap_read_unlock(mm);
2226
2227out_mmput:
2228 mmput(mm);
2229out:
2230 return rc;
2231}
2232
2233struct map_files_info {
2234 unsigned long start;
2235 unsigned long end;
2236 fmode_t mode;
2237};
2238
2239/*
2240 * Only allow CAP_SYS_ADMIN and CAP_CHECKPOINT_RESTORE to follow the links, due
2241 * to concerns about how the symlinks may be used to bypass permissions on
2242 * ancestor directories in the path to the file in question.
2243 */
2244static const char *
2245proc_map_files_get_link(struct dentry *dentry,
2246 struct inode *inode,
2247 struct delayed_call *done)
2248{
2249 if (!checkpoint_restore_ns_capable(&init_user_ns))
2250 return ERR_PTR(-EPERM);
2251
2252 return proc_pid_get_link(dentry, inode, done);
2253}
2254
2255/*
2256 * Identical to proc_pid_link_inode_operations except for get_link()
2257 */
2258static const struct inode_operations proc_map_files_link_inode_operations = {
2259 .readlink = proc_pid_readlink,
2260 .get_link = proc_map_files_get_link,
2261 .setattr = proc_setattr,
2262};
2263
2264static struct dentry *
2265proc_map_files_instantiate(struct dentry *dentry,
2266 struct task_struct *task, const void *ptr)
2267{
2268 fmode_t mode = (fmode_t)(unsigned long)ptr;
2269 struct proc_inode *ei;
2270 struct inode *inode;
2271
2272 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK |
2273 ((mode & FMODE_READ ) ? S_IRUSR : 0) |
2274 ((mode & FMODE_WRITE) ? S_IWUSR : 0));
2275 if (!inode)
2276 return ERR_PTR(-ENOENT);
2277
2278 ei = PROC_I(inode);
2279 ei->op.proc_get_link = map_files_get_link;
2280
2281 inode->i_op = &proc_map_files_link_inode_operations;
2282 inode->i_size = 64;
2283
2284 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2285 return d_splice_alias(inode, dentry);
2286}
2287
2288static struct dentry *proc_map_files_lookup(struct inode *dir,
2289 struct dentry *dentry, unsigned int flags)
2290{
2291 unsigned long vm_start, vm_end;
2292 struct vm_area_struct *vma;
2293 struct task_struct *task;
2294 struct dentry *result;
2295 struct mm_struct *mm;
2296
2297 result = ERR_PTR(-ENOENT);
2298 task = get_proc_task(dir);
2299 if (!task)
2300 goto out;
2301
2302 result = ERR_PTR(-EACCES);
2303 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2304 goto out_put_task;
2305
2306 result = ERR_PTR(-ENOENT);
2307 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2308 goto out_put_task;
2309
2310 mm = get_task_mm(task);
2311 if (!mm)
2312 goto out_put_task;
2313
2314 result = ERR_PTR(-EINTR);
2315 if (mmap_read_lock_killable(mm))
2316 goto out_put_mm;
2317
2318 result = ERR_PTR(-ENOENT);
2319 vma = find_exact_vma(mm, vm_start, vm_end);
2320 if (!vma)
2321 goto out_no_vma;
2322
2323 if (vma->vm_file)
2324 result = proc_map_files_instantiate(dentry, task,
2325 (void *)(unsigned long)vma->vm_file->f_mode);
2326
2327out_no_vma:
2328 mmap_read_unlock(mm);
2329out_put_mm:
2330 mmput(mm);
2331out_put_task:
2332 put_task_struct(task);
2333out:
2334 return result;
2335}
2336
2337static const struct inode_operations proc_map_files_inode_operations = {
2338 .lookup = proc_map_files_lookup,
2339 .permission = proc_fd_permission,
2340 .setattr = proc_setattr,
2341};
2342
2343static int
2344proc_map_files_readdir(struct file *file, struct dir_context *ctx)
2345{
2346 struct vm_area_struct *vma;
2347 struct task_struct *task;
2348 struct mm_struct *mm;
2349 unsigned long nr_files, pos, i;
2350 GENRADIX(struct map_files_info) fa;
2351 struct map_files_info *p;
2352 int ret;
2353 struct vma_iterator vmi;
2354
2355 genradix_init(&fa);
2356
2357 ret = -ENOENT;
2358 task = get_proc_task(file_inode(file));
2359 if (!task)
2360 goto out;
2361
2362 ret = -EACCES;
2363 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2364 goto out_put_task;
2365
2366 ret = 0;
2367 if (!dir_emit_dots(file, ctx))
2368 goto out_put_task;
2369
2370 mm = get_task_mm(task);
2371 if (!mm)
2372 goto out_put_task;
2373
2374 ret = mmap_read_lock_killable(mm);
2375 if (ret) {
2376 mmput(mm);
2377 goto out_put_task;
2378 }
2379
2380 nr_files = 0;
2381
2382 /*
2383 * We need two passes here:
2384 *
2385 * 1) Collect vmas of mapped files with mmap_lock taken
2386 * 2) Release mmap_lock and instantiate entries
2387 *
2388 * otherwise we get lockdep complained, since filldir()
2389 * routine might require mmap_lock taken in might_fault().
2390 */
2391
2392 pos = 2;
2393 vma_iter_init(&vmi, mm, 0);
2394 for_each_vma(vmi, vma) {
2395 if (!vma->vm_file)
2396 continue;
2397 if (++pos <= ctx->pos)
2398 continue;
2399
2400 p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL);
2401 if (!p) {
2402 ret = -ENOMEM;
2403 mmap_read_unlock(mm);
2404 mmput(mm);
2405 goto out_put_task;
2406 }
2407
2408 p->start = vma->vm_start;
2409 p->end = vma->vm_end;
2410 p->mode = vma->vm_file->f_mode;
2411 }
2412 mmap_read_unlock(mm);
2413 mmput(mm);
2414
2415 for (i = 0; i < nr_files; i++) {
2416 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */
2417 unsigned int len;
2418
2419 p = genradix_ptr(&fa, i);
2420 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);
2421 if (!proc_fill_cache(file, ctx,
2422 buf, len,
2423 proc_map_files_instantiate,
2424 task,
2425 (void *)(unsigned long)p->mode))
2426 break;
2427 ctx->pos++;
2428 }
2429
2430out_put_task:
2431 put_task_struct(task);
2432out:
2433 genradix_free(&fa);
2434 return ret;
2435}
2436
2437static const struct file_operations proc_map_files_operations = {
2438 .read = generic_read_dir,
2439 .iterate_shared = proc_map_files_readdir,
2440 .llseek = generic_file_llseek,
2441};
2442
2443#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
2444struct timers_private {
2445 struct pid *pid;
2446 struct task_struct *task;
2447 struct sighand_struct *sighand;
2448 struct pid_namespace *ns;
2449 unsigned long flags;
2450};
2451
2452static void *timers_start(struct seq_file *m, loff_t *pos)
2453{
2454 struct timers_private *tp = m->private;
2455
2456 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2457 if (!tp->task)
2458 return ERR_PTR(-ESRCH);
2459
2460 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2461 if (!tp->sighand)
2462 return ERR_PTR(-ESRCH);
2463
2464 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2465}
2466
2467static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2468{
2469 struct timers_private *tp = m->private;
2470 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2471}
2472
2473static void timers_stop(struct seq_file *m, void *v)
2474{
2475 struct timers_private *tp = m->private;
2476
2477 if (tp->sighand) {
2478 unlock_task_sighand(tp->task, &tp->flags);
2479 tp->sighand = NULL;
2480 }
2481
2482 if (tp->task) {
2483 put_task_struct(tp->task);
2484 tp->task = NULL;
2485 }
2486}
2487
2488static int show_timer(struct seq_file *m, void *v)
2489{
2490 struct k_itimer *timer;
2491 struct timers_private *tp = m->private;
2492 int notify;
2493 static const char * const nstr[] = {
2494 [SIGEV_SIGNAL] = "signal",
2495 [SIGEV_NONE] = "none",
2496 [SIGEV_THREAD] = "thread",
2497 };
2498
2499 timer = list_entry((struct list_head *)v, struct k_itimer, list);
2500 notify = timer->it_sigev_notify;
2501
2502 seq_printf(m, "ID: %d\n", timer->it_id);
2503 seq_printf(m, "signal: %d/%px\n",
2504 timer->sigq->info.si_signo,
2505 timer->sigq->info.si_value.sival_ptr);
2506 seq_printf(m, "notify: %s/%s.%d\n",
2507 nstr[notify & ~SIGEV_THREAD_ID],
2508 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2509 pid_nr_ns(timer->it_pid, tp->ns));
2510 seq_printf(m, "ClockID: %d\n", timer->it_clock);
2511
2512 return 0;
2513}
2514
2515static const struct seq_operations proc_timers_seq_ops = {
2516 .start = timers_start,
2517 .next = timers_next,
2518 .stop = timers_stop,
2519 .show = show_timer,
2520};
2521
2522static int proc_timers_open(struct inode *inode, struct file *file)
2523{
2524 struct timers_private *tp;
2525
2526 tp = __seq_open_private(file, &proc_timers_seq_ops,
2527 sizeof(struct timers_private));
2528 if (!tp)
2529 return -ENOMEM;
2530
2531 tp->pid = proc_pid(inode);
2532 tp->ns = proc_pid_ns(inode->i_sb);
2533 return 0;
2534}
2535
2536static const struct file_operations proc_timers_operations = {
2537 .open = proc_timers_open,
2538 .read = seq_read,
2539 .llseek = seq_lseek,
2540 .release = seq_release_private,
2541};
2542#endif
2543
2544static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2545 size_t count, loff_t *offset)
2546{
2547 struct inode *inode = file_inode(file);
2548 struct task_struct *p;
2549 u64 slack_ns;
2550 int err;
2551
2552 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2553 if (err < 0)
2554 return err;
2555
2556 p = get_proc_task(inode);
2557 if (!p)
2558 return -ESRCH;
2559
2560 if (p != current) {
2561 rcu_read_lock();
2562 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
2563 rcu_read_unlock();
2564 count = -EPERM;
2565 goto out;
2566 }
2567 rcu_read_unlock();
2568
2569 err = security_task_setscheduler(p);
2570 if (err) {
2571 count = err;
2572 goto out;
2573 }
2574 }
2575
2576 task_lock(p);
2577 if (slack_ns == 0)
2578 p->timer_slack_ns = p->default_timer_slack_ns;
2579 else
2580 p->timer_slack_ns = slack_ns;
2581 task_unlock(p);
2582
2583out:
2584 put_task_struct(p);
2585
2586 return count;
2587}
2588
2589static int timerslack_ns_show(struct seq_file *m, void *v)
2590{
2591 struct inode *inode = m->private;
2592 struct task_struct *p;
2593 int err = 0;
2594
2595 p = get_proc_task(inode);
2596 if (!p)
2597 return -ESRCH;
2598
2599 if (p != current) {
2600 rcu_read_lock();
2601 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
2602 rcu_read_unlock();
2603 err = -EPERM;
2604 goto out;
2605 }
2606 rcu_read_unlock();
2607
2608 err = security_task_getscheduler(p);
2609 if (err)
2610 goto out;
2611 }
2612
2613 task_lock(p);
2614 seq_printf(m, "%llu\n", p->timer_slack_ns);
2615 task_unlock(p);
2616
2617out:
2618 put_task_struct(p);
2619
2620 return err;
2621}
2622
2623static int timerslack_ns_open(struct inode *inode, struct file *filp)
2624{
2625 return single_open(filp, timerslack_ns_show, inode);
2626}
2627
2628static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2629 .open = timerslack_ns_open,
2630 .read = seq_read,
2631 .write = timerslack_ns_write,
2632 .llseek = seq_lseek,
2633 .release = single_release,
2634};
2635
2636static struct dentry *proc_pident_instantiate(struct dentry *dentry,
2637 struct task_struct *task, const void *ptr)
2638{
2639 const struct pid_entry *p = ptr;
2640 struct inode *inode;
2641 struct proc_inode *ei;
2642
2643 inode = proc_pid_make_inode(dentry->d_sb, task, p->mode);
2644 if (!inode)
2645 return ERR_PTR(-ENOENT);
2646
2647 ei = PROC_I(inode);
2648 if (S_ISDIR(inode->i_mode))
2649 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2650 if (p->iop)
2651 inode->i_op = p->iop;
2652 if (p->fop)
2653 inode->i_fop = p->fop;
2654 ei->op = p->op;
2655 pid_update_inode(task, inode);
2656 d_set_d_op(dentry, &pid_dentry_operations);
2657 return d_splice_alias(inode, dentry);
2658}
2659
2660static struct dentry *proc_pident_lookup(struct inode *dir,
2661 struct dentry *dentry,
2662 const struct pid_entry *p,
2663 const struct pid_entry *end)
2664{
2665 struct task_struct *task = get_proc_task(dir);
2666 struct dentry *res = ERR_PTR(-ENOENT);
2667
2668 if (!task)
2669 goto out_no_task;
2670
2671 /*
2672 * Yes, it does not scale. And it should not. Don't add
2673 * new entries into /proc/<tgid>/ without very good reasons.
2674 */
2675 for (; p < end; p++) {
2676 if (p->len != dentry->d_name.len)
2677 continue;
2678 if (!memcmp(dentry->d_name.name, p->name, p->len)) {
2679 res = proc_pident_instantiate(dentry, task, p);
2680 break;
2681 }
2682 }
2683 put_task_struct(task);
2684out_no_task:
2685 return res;
2686}
2687
2688static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
2689 const struct pid_entry *ents, unsigned int nents)
2690{
2691 struct task_struct *task = get_proc_task(file_inode(file));
2692 const struct pid_entry *p;
2693
2694 if (!task)
2695 return -ENOENT;
2696
2697 if (!dir_emit_dots(file, ctx))
2698 goto out;
2699
2700 if (ctx->pos >= nents + 2)
2701 goto out;
2702
2703 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
2704 if (!proc_fill_cache(file, ctx, p->name, p->len,
2705 proc_pident_instantiate, task, p))
2706 break;
2707 ctx->pos++;
2708 }
2709out:
2710 put_task_struct(task);
2711 return 0;
2712}
2713
2714#ifdef CONFIG_SECURITY
2715static int proc_pid_attr_open(struct inode *inode, struct file *file)
2716{
2717 file->private_data = NULL;
2718 __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
2719 return 0;
2720}
2721
2722static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2723 size_t count, loff_t *ppos)
2724{
2725 struct inode * inode = file_inode(file);
2726 char *p = NULL;
2727 ssize_t length;
2728 struct task_struct *task = get_proc_task(inode);
2729
2730 if (!task)
2731 return -ESRCH;
2732
2733 length = security_getprocattr(task, PROC_I(inode)->op.lsm,
2734 file->f_path.dentry->d_name.name,
2735 &p);
2736 put_task_struct(task);
2737 if (length > 0)
2738 length = simple_read_from_buffer(buf, count, ppos, p, length);
2739 kfree(p);
2740 return length;
2741}
2742
2743static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2744 size_t count, loff_t *ppos)
2745{
2746 struct inode * inode = file_inode(file);
2747 struct task_struct *task;
2748 void *page;
2749 int rv;
2750
2751 /* A task may only write when it was the opener. */
2752 if (file->private_data != current->mm)
2753 return -EPERM;
2754
2755 rcu_read_lock();
2756 task = pid_task(proc_pid(inode), PIDTYPE_PID);
2757 if (!task) {
2758 rcu_read_unlock();
2759 return -ESRCH;
2760 }
2761 /* A task may only write its own attributes. */
2762 if (current != task) {
2763 rcu_read_unlock();
2764 return -EACCES;
2765 }
2766 /* Prevent changes to overridden credentials. */
2767 if (current_cred() != current_real_cred()) {
2768 rcu_read_unlock();
2769 return -EBUSY;
2770 }
2771 rcu_read_unlock();
2772
2773 if (count > PAGE_SIZE)
2774 count = PAGE_SIZE;
2775
2776 /* No partial writes. */
2777 if (*ppos != 0)
2778 return -EINVAL;
2779
2780 page = memdup_user(buf, count);
2781 if (IS_ERR(page)) {
2782 rv = PTR_ERR(page);
2783 goto out;
2784 }
2785
2786 /* Guard against adverse ptrace interaction */
2787 rv = mutex_lock_interruptible(¤t->signal->cred_guard_mutex);
2788 if (rv < 0)
2789 goto out_free;
2790
2791 rv = security_setprocattr(PROC_I(inode)->op.lsm,
2792 file->f_path.dentry->d_name.name, page,
2793 count);
2794 mutex_unlock(¤t->signal->cred_guard_mutex);
2795out_free:
2796 kfree(page);
2797out:
2798 return rv;
2799}
2800
2801static const struct file_operations proc_pid_attr_operations = {
2802 .open = proc_pid_attr_open,
2803 .read = proc_pid_attr_read,
2804 .write = proc_pid_attr_write,
2805 .llseek = generic_file_llseek,
2806 .release = mem_release,
2807};
2808
2809#define LSM_DIR_OPS(LSM) \
2810static int proc_##LSM##_attr_dir_iterate(struct file *filp, \
2811 struct dir_context *ctx) \
2812{ \
2813 return proc_pident_readdir(filp, ctx, \
2814 LSM##_attr_dir_stuff, \
2815 ARRAY_SIZE(LSM##_attr_dir_stuff)); \
2816} \
2817\
2818static const struct file_operations proc_##LSM##_attr_dir_ops = { \
2819 .read = generic_read_dir, \
2820 .iterate = proc_##LSM##_attr_dir_iterate, \
2821 .llseek = default_llseek, \
2822}; \
2823\
2824static struct dentry *proc_##LSM##_attr_dir_lookup(struct inode *dir, \
2825 struct dentry *dentry, unsigned int flags) \
2826{ \
2827 return proc_pident_lookup(dir, dentry, \
2828 LSM##_attr_dir_stuff, \
2829 LSM##_attr_dir_stuff + ARRAY_SIZE(LSM##_attr_dir_stuff)); \
2830} \
2831\
2832static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \
2833 .lookup = proc_##LSM##_attr_dir_lookup, \
2834 .getattr = pid_getattr, \
2835 .setattr = proc_setattr, \
2836}
2837
2838#ifdef CONFIG_SECURITY_SMACK
2839static const struct pid_entry smack_attr_dir_stuff[] = {
2840 ATTR("smack", "current", 0666),
2841};
2842LSM_DIR_OPS(smack);
2843#endif
2844
2845#ifdef CONFIG_SECURITY_APPARMOR
2846static const struct pid_entry apparmor_attr_dir_stuff[] = {
2847 ATTR("apparmor", "current", 0666),
2848 ATTR("apparmor", "prev", 0444),
2849 ATTR("apparmor", "exec", 0666),
2850};
2851LSM_DIR_OPS(apparmor);
2852#endif
2853
2854static const struct pid_entry attr_dir_stuff[] = {
2855 ATTR(NULL, "current", 0666),
2856 ATTR(NULL, "prev", 0444),
2857 ATTR(NULL, "exec", 0666),
2858 ATTR(NULL, "fscreate", 0666),
2859 ATTR(NULL, "keycreate", 0666),
2860 ATTR(NULL, "sockcreate", 0666),
2861#ifdef CONFIG_SECURITY_SMACK
2862 DIR("smack", 0555,
2863 proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
2864#endif
2865#ifdef CONFIG_SECURITY_APPARMOR
2866 DIR("apparmor", 0555,
2867 proc_apparmor_attr_dir_inode_ops, proc_apparmor_attr_dir_ops),
2868#endif
2869};
2870
2871static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
2872{
2873 return proc_pident_readdir(file, ctx,
2874 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2875}
2876
2877static const struct file_operations proc_attr_dir_operations = {
2878 .read = generic_read_dir,
2879 .iterate_shared = proc_attr_dir_readdir,
2880 .llseek = generic_file_llseek,
2881};
2882
2883static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2884 struct dentry *dentry, unsigned int flags)
2885{
2886 return proc_pident_lookup(dir, dentry,
2887 attr_dir_stuff,
2888 attr_dir_stuff + ARRAY_SIZE(attr_dir_stuff));
2889}
2890
2891static const struct inode_operations proc_attr_dir_inode_operations = {
2892 .lookup = proc_attr_dir_lookup,
2893 .getattr = pid_getattr,
2894 .setattr = proc_setattr,
2895};
2896
2897#endif
2898
2899#ifdef CONFIG_ELF_CORE
2900static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2901 size_t count, loff_t *ppos)
2902{
2903 struct task_struct *task = get_proc_task(file_inode(file));
2904 struct mm_struct *mm;
2905 char buffer[PROC_NUMBUF];
2906 size_t len;
2907 int ret;
2908
2909 if (!task)
2910 return -ESRCH;
2911
2912 ret = 0;
2913 mm = get_task_mm(task);
2914 if (mm) {
2915 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2916 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2917 MMF_DUMP_FILTER_SHIFT));
2918 mmput(mm);
2919 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2920 }
2921
2922 put_task_struct(task);
2923
2924 return ret;
2925}
2926
2927static ssize_t proc_coredump_filter_write(struct file *file,
2928 const char __user *buf,
2929 size_t count,
2930 loff_t *ppos)
2931{
2932 struct task_struct *task;
2933 struct mm_struct *mm;
2934 unsigned int val;
2935 int ret;
2936 int i;
2937 unsigned long mask;
2938
2939 ret = kstrtouint_from_user(buf, count, 0, &val);
2940 if (ret < 0)
2941 return ret;
2942
2943 ret = -ESRCH;
2944 task = get_proc_task(file_inode(file));
2945 if (!task)
2946 goto out_no_task;
2947
2948 mm = get_task_mm(task);
2949 if (!mm)
2950 goto out_no_mm;
2951 ret = 0;
2952
2953 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2954 if (val & mask)
2955 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2956 else
2957 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2958 }
2959
2960 mmput(mm);
2961 out_no_mm:
2962 put_task_struct(task);
2963 out_no_task:
2964 if (ret < 0)
2965 return ret;
2966 return count;
2967}
2968
2969static const struct file_operations proc_coredump_filter_operations = {
2970 .read = proc_coredump_filter_read,
2971 .write = proc_coredump_filter_write,
2972 .llseek = generic_file_llseek,
2973};
2974#endif
2975
2976#ifdef CONFIG_TASK_IO_ACCOUNTING
2977static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
2978{
2979 struct task_io_accounting acct = task->ioac;
2980 unsigned long flags;
2981 int result;
2982
2983 result = down_read_killable(&task->signal->exec_update_lock);
2984 if (result)
2985 return result;
2986
2987 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
2988 result = -EACCES;
2989 goto out_unlock;
2990 }
2991
2992 if (whole && lock_task_sighand(task, &flags)) {
2993 struct task_struct *t = task;
2994
2995 task_io_accounting_add(&acct, &task->signal->ioac);
2996 while_each_thread(task, t)
2997 task_io_accounting_add(&acct, &t->ioac);
2998
2999 unlock_task_sighand(task, &flags);
3000 }
3001 seq_printf(m,
3002 "rchar: %llu\n"
3003 "wchar: %llu\n"
3004 "syscr: %llu\n"
3005 "syscw: %llu\n"
3006 "read_bytes: %llu\n"
3007 "write_bytes: %llu\n"
3008 "cancelled_write_bytes: %llu\n",
3009 (unsigned long long)acct.rchar,
3010 (unsigned long long)acct.wchar,
3011 (unsigned long long)acct.syscr,
3012 (unsigned long long)acct.syscw,
3013 (unsigned long long)acct.read_bytes,
3014 (unsigned long long)acct.write_bytes,
3015 (unsigned long long)acct.cancelled_write_bytes);
3016 result = 0;
3017
3018out_unlock:
3019 up_read(&task->signal->exec_update_lock);
3020 return result;
3021}
3022
3023static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
3024 struct pid *pid, struct task_struct *task)
3025{
3026 return do_io_accounting(task, m, 0);
3027}
3028
3029static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
3030 struct pid *pid, struct task_struct *task)
3031{
3032 return do_io_accounting(task, m, 1);
3033}
3034#endif /* CONFIG_TASK_IO_ACCOUNTING */
3035
3036#ifdef CONFIG_USER_NS
3037static int proc_id_map_open(struct inode *inode, struct file *file,
3038 const struct seq_operations *seq_ops)
3039{
3040 struct user_namespace *ns = NULL;
3041 struct task_struct *task;
3042 struct seq_file *seq;
3043 int ret = -EINVAL;
3044
3045 task = get_proc_task(inode);
3046 if (task) {
3047 rcu_read_lock();
3048 ns = get_user_ns(task_cred_xxx(task, user_ns));
3049 rcu_read_unlock();
3050 put_task_struct(task);
3051 }
3052 if (!ns)
3053 goto err;
3054
3055 ret = seq_open(file, seq_ops);
3056 if (ret)
3057 goto err_put_ns;
3058
3059 seq = file->private_data;
3060 seq->private = ns;
3061
3062 return 0;
3063err_put_ns:
3064 put_user_ns(ns);
3065err:
3066 return ret;
3067}
3068
3069static int proc_id_map_release(struct inode *inode, struct file *file)
3070{
3071 struct seq_file *seq = file->private_data;
3072 struct user_namespace *ns = seq->private;
3073 put_user_ns(ns);
3074 return seq_release(inode, file);
3075}
3076
3077static int proc_uid_map_open(struct inode *inode, struct file *file)
3078{
3079 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
3080}
3081
3082static int proc_gid_map_open(struct inode *inode, struct file *file)
3083{
3084 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
3085}
3086
3087static int proc_projid_map_open(struct inode *inode, struct file *file)
3088{
3089 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
3090}
3091
3092static const struct file_operations proc_uid_map_operations = {
3093 .open = proc_uid_map_open,
3094 .write = proc_uid_map_write,
3095 .read = seq_read,
3096 .llseek = seq_lseek,
3097 .release = proc_id_map_release,
3098};
3099
3100static const struct file_operations proc_gid_map_operations = {
3101 .open = proc_gid_map_open,
3102 .write = proc_gid_map_write,
3103 .read = seq_read,
3104 .llseek = seq_lseek,
3105 .release = proc_id_map_release,
3106};
3107
3108static const struct file_operations proc_projid_map_operations = {
3109 .open = proc_projid_map_open,
3110 .write = proc_projid_map_write,
3111 .read = seq_read,
3112 .llseek = seq_lseek,
3113 .release = proc_id_map_release,
3114};
3115
3116static int proc_setgroups_open(struct inode *inode, struct file *file)
3117{
3118 struct user_namespace *ns = NULL;
3119 struct task_struct *task;
3120 int ret;
3121
3122 ret = -ESRCH;
3123 task = get_proc_task(inode);
3124 if (task) {
3125 rcu_read_lock();
3126 ns = get_user_ns(task_cred_xxx(task, user_ns));
3127 rcu_read_unlock();
3128 put_task_struct(task);
3129 }
3130 if (!ns)
3131 goto err;
3132
3133 if (file->f_mode & FMODE_WRITE) {
3134 ret = -EACCES;
3135 if (!ns_capable(ns, CAP_SYS_ADMIN))
3136 goto err_put_ns;
3137 }
3138
3139 ret = single_open(file, &proc_setgroups_show, ns);
3140 if (ret)
3141 goto err_put_ns;
3142
3143 return 0;
3144err_put_ns:
3145 put_user_ns(ns);
3146err:
3147 return ret;
3148}
3149
3150static int proc_setgroups_release(struct inode *inode, struct file *file)
3151{
3152 struct seq_file *seq = file->private_data;
3153 struct user_namespace *ns = seq->private;
3154 int ret = single_release(inode, file);
3155 put_user_ns(ns);
3156 return ret;
3157}
3158
3159static const struct file_operations proc_setgroups_operations = {
3160 .open = proc_setgroups_open,
3161 .write = proc_setgroups_write,
3162 .read = seq_read,
3163 .llseek = seq_lseek,
3164 .release = proc_setgroups_release,
3165};
3166#endif /* CONFIG_USER_NS */
3167
3168static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
3169 struct pid *pid, struct task_struct *task)
3170{
3171 int err = lock_trace(task);
3172 if (!err) {
3173 seq_printf(m, "%08x\n", task->personality);
3174 unlock_trace(task);
3175 }
3176 return err;
3177}
3178
3179#ifdef CONFIG_LIVEPATCH
3180static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns,
3181 struct pid *pid, struct task_struct *task)
3182{
3183 seq_printf(m, "%d\n", task->patch_state);
3184 return 0;
3185}
3186#endif /* CONFIG_LIVEPATCH */
3187
3188#ifdef CONFIG_KSM
3189static int proc_pid_ksm_merging_pages(struct seq_file *m, struct pid_namespace *ns,
3190 struct pid *pid, struct task_struct *task)
3191{
3192 struct mm_struct *mm;
3193
3194 mm = get_task_mm(task);
3195 if (mm) {
3196 seq_printf(m, "%lu\n", mm->ksm_merging_pages);
3197 mmput(mm);
3198 }
3199
3200 return 0;
3201}
3202static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns,
3203 struct pid *pid, struct task_struct *task)
3204{
3205 struct mm_struct *mm;
3206
3207 mm = get_task_mm(task);
3208 if (mm) {
3209 seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items);
3210 mmput(mm);
3211 }
3212
3213 return 0;
3214}
3215#endif /* CONFIG_KSM */
3216
3217#ifdef CONFIG_STACKLEAK_METRICS
3218static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns,
3219 struct pid *pid, struct task_struct *task)
3220{
3221 unsigned long prev_depth = THREAD_SIZE -
3222 (task->prev_lowest_stack & (THREAD_SIZE - 1));
3223 unsigned long depth = THREAD_SIZE -
3224 (task->lowest_stack & (THREAD_SIZE - 1));
3225
3226 seq_printf(m, "previous stack depth: %lu\nstack depth: %lu\n",
3227 prev_depth, depth);
3228 return 0;
3229}
3230#endif /* CONFIG_STACKLEAK_METRICS */
3231
3232/*
3233 * Thread groups
3234 */
3235static const struct file_operations proc_task_operations;
3236static const struct inode_operations proc_task_inode_operations;
3237
3238static const struct pid_entry tgid_base_stuff[] = {
3239 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
3240 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3241 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
3242 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3243 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3244#ifdef CONFIG_NET
3245 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3246#endif
3247 REG("environ", S_IRUSR, proc_environ_operations),
3248 REG("auxv", S_IRUSR, proc_auxv_operations),
3249 ONE("status", S_IRUGO, proc_pid_status),
3250 ONE("personality", S_IRUSR, proc_pid_personality),
3251 ONE("limits", S_IRUGO, proc_pid_limits),
3252#ifdef CONFIG_SCHED_DEBUG
3253 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3254#endif
3255#ifdef CONFIG_SCHED_AUTOGROUP
3256 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
3257#endif
3258#ifdef CONFIG_TIME_NS
3259 REG("timens_offsets", S_IRUGO|S_IWUSR, proc_timens_offsets_operations),
3260#endif
3261 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3262#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3263 ONE("syscall", S_IRUSR, proc_pid_syscall),
3264#endif
3265 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3266 ONE("stat", S_IRUGO, proc_tgid_stat),
3267 ONE("statm", S_IRUGO, proc_pid_statm),
3268 REG("maps", S_IRUGO, proc_pid_maps_operations),
3269#ifdef CONFIG_NUMA
3270 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
3271#endif
3272 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3273 LNK("cwd", proc_cwd_link),
3274 LNK("root", proc_root_link),
3275 LNK("exe", proc_exe_link),
3276 REG("mounts", S_IRUGO, proc_mounts_operations),
3277 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3278 REG("mountstats", S_IRUSR, proc_mountstats_operations),
3279#ifdef CONFIG_PROC_PAGE_MONITOR
3280 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3281 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
3282 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3283 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3284#endif
3285#ifdef CONFIG_SECURITY
3286 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3287#endif
3288#ifdef CONFIG_KALLSYMS
3289 ONE("wchan", S_IRUGO, proc_pid_wchan),
3290#endif
3291#ifdef CONFIG_STACKTRACE
3292 ONE("stack", S_IRUSR, proc_pid_stack),
3293#endif
3294#ifdef CONFIG_SCHED_INFO
3295 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3296#endif
3297#ifdef CONFIG_LATENCYTOP
3298 REG("latency", S_IRUGO, proc_lstats_operations),
3299#endif
3300#ifdef CONFIG_PROC_PID_CPUSET
3301 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3302#endif
3303#ifdef CONFIG_CGROUPS
3304 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3305#endif
3306#ifdef CONFIG_PROC_CPU_RESCTRL
3307 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),
3308#endif
3309 ONE("oom_score", S_IRUGO, proc_oom_score),
3310 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3311 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3312#ifdef CONFIG_AUDIT
3313 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3314 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3315#endif
3316#ifdef CONFIG_FAULT_INJECTION
3317 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3318 REG("fail-nth", 0644, proc_fail_nth_operations),
3319#endif
3320#ifdef CONFIG_ELF_CORE
3321 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3322#endif
3323#ifdef CONFIG_TASK_IO_ACCOUNTING
3324 ONE("io", S_IRUSR, proc_tgid_io_accounting),
3325#endif
3326#ifdef CONFIG_USER_NS
3327 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3328 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3329 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3330 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3331#endif
3332#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
3333 REG("timers", S_IRUGO, proc_timers_operations),
3334#endif
3335 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
3336#ifdef CONFIG_LIVEPATCH
3337 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3338#endif
3339#ifdef CONFIG_STACKLEAK_METRICS
3340 ONE("stack_depth", S_IRUGO, proc_stack_depth),
3341#endif
3342#ifdef CONFIG_PROC_PID_ARCH_STATUS
3343 ONE("arch_status", S_IRUGO, proc_pid_arch_status),
3344#endif
3345#ifdef CONFIG_SECCOMP_CACHE_DEBUG
3346 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),
3347#endif
3348#ifdef CONFIG_KSM
3349 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages),
3350 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat),
3351#endif
3352};
3353
3354static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
3355{
3356 return proc_pident_readdir(file, ctx,
3357 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3358}
3359
3360static const struct file_operations proc_tgid_base_operations = {
3361 .read = generic_read_dir,
3362 .iterate_shared = proc_tgid_base_readdir,
3363 .llseek = generic_file_llseek,
3364};
3365
3366struct pid *tgid_pidfd_to_pid(const struct file *file)
3367{
3368 if (file->f_op != &proc_tgid_base_operations)
3369 return ERR_PTR(-EBADF);
3370
3371 return proc_pid(file_inode(file));
3372}
3373
3374static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3375{
3376 return proc_pident_lookup(dir, dentry,
3377 tgid_base_stuff,
3378 tgid_base_stuff + ARRAY_SIZE(tgid_base_stuff));
3379}
3380
3381static const struct inode_operations proc_tgid_base_inode_operations = {
3382 .lookup = proc_tgid_base_lookup,
3383 .getattr = pid_getattr,
3384 .setattr = proc_setattr,
3385 .permission = proc_pid_permission,
3386};
3387
3388/**
3389 * proc_flush_pid - Remove dcache entries for @pid from the /proc dcache.
3390 * @pid: pid that should be flushed.
3391 *
3392 * This function walks a list of inodes (that belong to any proc
3393 * filesystem) that are attached to the pid and flushes them from
3394 * the dentry cache.
3395 *
3396 * It is safe and reasonable to cache /proc entries for a task until
3397 * that task exits. After that they just clog up the dcache with
3398 * useless entries, possibly causing useful dcache entries to be
3399 * flushed instead. This routine is provided to flush those useless
3400 * dcache entries when a process is reaped.
3401 *
3402 * NOTE: This routine is just an optimization so it does not guarantee
3403 * that no dcache entries will exist after a process is reaped
3404 * it just makes it very unlikely that any will persist.
3405 */
3406
3407void proc_flush_pid(struct pid *pid)
3408{
3409 proc_invalidate_siblings_dcache(&pid->inodes, &pid->lock);
3410}
3411
3412static struct dentry *proc_pid_instantiate(struct dentry * dentry,
3413 struct task_struct *task, const void *ptr)
3414{
3415 struct inode *inode;
3416
3417 inode = proc_pid_make_base_inode(dentry->d_sb, task,
3418 S_IFDIR | S_IRUGO | S_IXUGO);
3419 if (!inode)
3420 return ERR_PTR(-ENOENT);
3421
3422 inode->i_op = &proc_tgid_base_inode_operations;
3423 inode->i_fop = &proc_tgid_base_operations;
3424 inode->i_flags|=S_IMMUTABLE;
3425
3426 set_nlink(inode, nlink_tgid);
3427 pid_update_inode(task, inode);
3428
3429 d_set_d_op(dentry, &pid_dentry_operations);
3430 return d_splice_alias(inode, dentry);
3431}
3432
3433struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags)
3434{
3435 struct task_struct *task;
3436 unsigned tgid;
3437 struct proc_fs_info *fs_info;
3438 struct pid_namespace *ns;
3439 struct dentry *result = ERR_PTR(-ENOENT);
3440
3441 tgid = name_to_int(&dentry->d_name);
3442 if (tgid == ~0U)
3443 goto out;
3444
3445 fs_info = proc_sb_info(dentry->d_sb);
3446 ns = fs_info->pid_ns;
3447 rcu_read_lock();
3448 task = find_task_by_pid_ns(tgid, ns);
3449 if (task)
3450 get_task_struct(task);
3451 rcu_read_unlock();
3452 if (!task)
3453 goto out;
3454
3455 /* Limit procfs to only ptraceable tasks */
3456 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) {
3457 if (!has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS))
3458 goto out_put_task;
3459 }
3460
3461 result = proc_pid_instantiate(dentry, task, NULL);
3462out_put_task:
3463 put_task_struct(task);
3464out:
3465 return result;
3466}
3467
3468/*
3469 * Find the first task with tgid >= tgid
3470 *
3471 */
3472struct tgid_iter {
3473 unsigned int tgid;
3474 struct task_struct *task;
3475};
3476static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3477{
3478 struct pid *pid;
3479
3480 if (iter.task)
3481 put_task_struct(iter.task);
3482 rcu_read_lock();
3483retry:
3484 iter.task = NULL;
3485 pid = find_ge_pid(iter.tgid, ns);
3486 if (pid) {
3487 iter.tgid = pid_nr_ns(pid, ns);
3488 iter.task = pid_task(pid, PIDTYPE_TGID);
3489 if (!iter.task) {
3490 iter.tgid += 1;
3491 goto retry;
3492 }
3493 get_task_struct(iter.task);
3494 }
3495 rcu_read_unlock();
3496 return iter;
3497}
3498
3499#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
3500
3501/* for the /proc/ directory itself, after non-process stuff has been done */
3502int proc_pid_readdir(struct file *file, struct dir_context *ctx)
3503{
3504 struct tgid_iter iter;
3505 struct proc_fs_info *fs_info = proc_sb_info(file_inode(file)->i_sb);
3506 struct pid_namespace *ns = proc_pid_ns(file_inode(file)->i_sb);
3507 loff_t pos = ctx->pos;
3508
3509 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
3510 return 0;
3511
3512 if (pos == TGID_OFFSET - 2) {
3513 struct inode *inode = d_inode(fs_info->proc_self);
3514 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
3515 return 0;
3516 ctx->pos = pos = pos + 1;
3517 }
3518 if (pos == TGID_OFFSET - 1) {
3519 struct inode *inode = d_inode(fs_info->proc_thread_self);
3520 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3521 return 0;
3522 ctx->pos = pos = pos + 1;
3523 }
3524 iter.tgid = pos - TGID_OFFSET;
3525 iter.task = NULL;
3526 for (iter = next_tgid(ns, iter);
3527 iter.task;
3528 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3529 char name[10 + 1];
3530 unsigned int len;
3531
3532 cond_resched();
3533 if (!has_pid_permissions(fs_info, iter.task, HIDEPID_INVISIBLE))
3534 continue;
3535
3536 len = snprintf(name, sizeof(name), "%u", iter.tgid);
3537 ctx->pos = iter.tgid + TGID_OFFSET;
3538 if (!proc_fill_cache(file, ctx, name, len,
3539 proc_pid_instantiate, iter.task, NULL)) {
3540 put_task_struct(iter.task);
3541 return 0;
3542 }
3543 }
3544 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
3545 return 0;
3546}
3547
3548/*
3549 * proc_tid_comm_permission is a special permission function exclusively
3550 * used for the node /proc/<pid>/task/<tid>/comm.
3551 * It bypasses generic permission checks in the case where a task of the same
3552 * task group attempts to access the node.
3553 * The rationale behind this is that glibc and bionic access this node for
3554 * cross thread naming (pthread_set/getname_np(!self)). However, if
3555 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3556 * which locks out the cross thread naming implementation.
3557 * This function makes sure that the node is always accessible for members of
3558 * same thread group.
3559 */
3560static int proc_tid_comm_permission(struct user_namespace *mnt_userns,
3561 struct inode *inode, int mask)
3562{
3563 bool is_same_tgroup;
3564 struct task_struct *task;
3565
3566 task = get_proc_task(inode);
3567 if (!task)
3568 return -ESRCH;
3569 is_same_tgroup = same_thread_group(current, task);
3570 put_task_struct(task);
3571
3572 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3573 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3574 * read or written by the members of the corresponding
3575 * thread group.
3576 */
3577 return 0;
3578 }
3579
3580 return generic_permission(&init_user_ns, inode, mask);
3581}
3582
3583static const struct inode_operations proc_tid_comm_inode_operations = {
3584 .permission = proc_tid_comm_permission,
3585};
3586
3587/*
3588 * Tasks
3589 */
3590static const struct pid_entry tid_base_stuff[] = {
3591 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3592 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3593 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3594#ifdef CONFIG_NET
3595 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3596#endif
3597 REG("environ", S_IRUSR, proc_environ_operations),
3598 REG("auxv", S_IRUSR, proc_auxv_operations),
3599 ONE("status", S_IRUGO, proc_pid_status),
3600 ONE("personality", S_IRUSR, proc_pid_personality),
3601 ONE("limits", S_IRUGO, proc_pid_limits),
3602#ifdef CONFIG_SCHED_DEBUG
3603 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3604#endif
3605 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3606 &proc_tid_comm_inode_operations,
3607 &proc_pid_set_comm_operations, {}),
3608#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3609 ONE("syscall", S_IRUSR, proc_pid_syscall),
3610#endif
3611 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3612 ONE("stat", S_IRUGO, proc_tid_stat),
3613 ONE("statm", S_IRUGO, proc_pid_statm),
3614 REG("maps", S_IRUGO, proc_pid_maps_operations),
3615#ifdef CONFIG_PROC_CHILDREN
3616 REG("children", S_IRUGO, proc_tid_children_operations),
3617#endif
3618#ifdef CONFIG_NUMA
3619 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
3620#endif
3621 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3622 LNK("cwd", proc_cwd_link),
3623 LNK("root", proc_root_link),
3624 LNK("exe", proc_exe_link),
3625 REG("mounts", S_IRUGO, proc_mounts_operations),
3626 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3627#ifdef CONFIG_PROC_PAGE_MONITOR
3628 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3629 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
3630 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3631 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3632#endif
3633#ifdef CONFIG_SECURITY
3634 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3635#endif
3636#ifdef CONFIG_KALLSYMS
3637 ONE("wchan", S_IRUGO, proc_pid_wchan),
3638#endif
3639#ifdef CONFIG_STACKTRACE
3640 ONE("stack", S_IRUSR, proc_pid_stack),
3641#endif
3642#ifdef CONFIG_SCHED_INFO
3643 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3644#endif
3645#ifdef CONFIG_LATENCYTOP
3646 REG("latency", S_IRUGO, proc_lstats_operations),
3647#endif
3648#ifdef CONFIG_PROC_PID_CPUSET
3649 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3650#endif
3651#ifdef CONFIG_CGROUPS
3652 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3653#endif
3654#ifdef CONFIG_PROC_CPU_RESCTRL
3655 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),
3656#endif
3657 ONE("oom_score", S_IRUGO, proc_oom_score),
3658 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3659 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3660#ifdef CONFIG_AUDIT
3661 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3662 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3663#endif
3664#ifdef CONFIG_FAULT_INJECTION
3665 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3666 REG("fail-nth", 0644, proc_fail_nth_operations),
3667#endif
3668#ifdef CONFIG_TASK_IO_ACCOUNTING
3669 ONE("io", S_IRUSR, proc_tid_io_accounting),
3670#endif
3671#ifdef CONFIG_USER_NS
3672 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3673 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3674 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3675 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3676#endif
3677#ifdef CONFIG_LIVEPATCH
3678 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3679#endif
3680#ifdef CONFIG_PROC_PID_ARCH_STATUS
3681 ONE("arch_status", S_IRUGO, proc_pid_arch_status),
3682#endif
3683#ifdef CONFIG_SECCOMP_CACHE_DEBUG
3684 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),
3685#endif
3686#ifdef CONFIG_KSM
3687 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages),
3688 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat),
3689#endif
3690};
3691
3692static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
3693{
3694 return proc_pident_readdir(file, ctx,
3695 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3696}
3697
3698static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3699{
3700 return proc_pident_lookup(dir, dentry,
3701 tid_base_stuff,
3702 tid_base_stuff + ARRAY_SIZE(tid_base_stuff));
3703}
3704
3705static const struct file_operations proc_tid_base_operations = {
3706 .read = generic_read_dir,
3707 .iterate_shared = proc_tid_base_readdir,
3708 .llseek = generic_file_llseek,
3709};
3710
3711static const struct inode_operations proc_tid_base_inode_operations = {
3712 .lookup = proc_tid_base_lookup,
3713 .getattr = pid_getattr,
3714 .setattr = proc_setattr,
3715};
3716
3717static struct dentry *proc_task_instantiate(struct dentry *dentry,
3718 struct task_struct *task, const void *ptr)
3719{
3720 struct inode *inode;
3721 inode = proc_pid_make_base_inode(dentry->d_sb, task,
3722 S_IFDIR | S_IRUGO | S_IXUGO);
3723 if (!inode)
3724 return ERR_PTR(-ENOENT);
3725
3726 inode->i_op = &proc_tid_base_inode_operations;
3727 inode->i_fop = &proc_tid_base_operations;
3728 inode->i_flags |= S_IMMUTABLE;
3729
3730 set_nlink(inode, nlink_tid);
3731 pid_update_inode(task, inode);
3732
3733 d_set_d_op(dentry, &pid_dentry_operations);
3734 return d_splice_alias(inode, dentry);
3735}
3736
3737static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3738{
3739 struct task_struct *task;
3740 struct task_struct *leader = get_proc_task(dir);
3741 unsigned tid;
3742 struct proc_fs_info *fs_info;
3743 struct pid_namespace *ns;
3744 struct dentry *result = ERR_PTR(-ENOENT);
3745
3746 if (!leader)
3747 goto out_no_task;
3748
3749 tid = name_to_int(&dentry->d_name);
3750 if (tid == ~0U)
3751 goto out;
3752
3753 fs_info = proc_sb_info(dentry->d_sb);
3754 ns = fs_info->pid_ns;
3755 rcu_read_lock();
3756 task = find_task_by_pid_ns(tid, ns);
3757 if (task)
3758 get_task_struct(task);
3759 rcu_read_unlock();
3760 if (!task)
3761 goto out;
3762 if (!same_thread_group(leader, task))
3763 goto out_drop_task;
3764
3765 result = proc_task_instantiate(dentry, task, NULL);
3766out_drop_task:
3767 put_task_struct(task);
3768out:
3769 put_task_struct(leader);
3770out_no_task:
3771 return result;
3772}
3773
3774/*
3775 * Find the first tid of a thread group to return to user space.
3776 *
3777 * Usually this is just the thread group leader, but if the users
3778 * buffer was too small or there was a seek into the middle of the
3779 * directory we have more work todo.
3780 *
3781 * In the case of a short read we start with find_task_by_pid.
3782 *
3783 * In the case of a seek we start with the leader and walk nr
3784 * threads past it.
3785 */
3786static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3787 struct pid_namespace *ns)
3788{
3789 struct task_struct *pos, *task;
3790 unsigned long nr = f_pos;
3791
3792 if (nr != f_pos) /* 32bit overflow? */
3793 return NULL;
3794
3795 rcu_read_lock();
3796 task = pid_task(pid, PIDTYPE_PID);
3797 if (!task)
3798 goto fail;
3799
3800 /* Attempt to start with the tid of a thread */
3801 if (tid && nr) {
3802 pos = find_task_by_pid_ns(tid, ns);
3803 if (pos && same_thread_group(pos, task))
3804 goto found;
3805 }
3806
3807 /* If nr exceeds the number of threads there is nothing todo */
3808 if (nr >= get_nr_threads(task))
3809 goto fail;
3810
3811 /* If we haven't found our starting place yet start
3812 * with the leader and walk nr threads forward.
3813 */
3814 pos = task = task->group_leader;
3815 do {
3816 if (!nr--)
3817 goto found;
3818 } while_each_thread(task, pos);
3819fail:
3820 pos = NULL;
3821 goto out;
3822found:
3823 get_task_struct(pos);
3824out:
3825 rcu_read_unlock();
3826 return pos;
3827}
3828
3829/*
3830 * Find the next thread in the thread list.
3831 * Return NULL if there is an error or no next thread.
3832 *
3833 * The reference to the input task_struct is released.
3834 */
3835static struct task_struct *next_tid(struct task_struct *start)
3836{
3837 struct task_struct *pos = NULL;
3838 rcu_read_lock();
3839 if (pid_alive(start)) {
3840 pos = next_thread(start);
3841 if (thread_group_leader(pos))
3842 pos = NULL;
3843 else
3844 get_task_struct(pos);
3845 }
3846 rcu_read_unlock();
3847 put_task_struct(start);
3848 return pos;
3849}
3850
3851/* for the /proc/TGID/task/ directories */
3852static int proc_task_readdir(struct file *file, struct dir_context *ctx)
3853{
3854 struct inode *inode = file_inode(file);
3855 struct task_struct *task;
3856 struct pid_namespace *ns;
3857 int tid;
3858
3859 if (proc_inode_is_dead(inode))
3860 return -ENOENT;
3861
3862 if (!dir_emit_dots(file, ctx))
3863 return 0;
3864
3865 /* f_version caches the tgid value that the last readdir call couldn't
3866 * return. lseek aka telldir automagically resets f_version to 0.
3867 */
3868 ns = proc_pid_ns(inode->i_sb);
3869 tid = (int)file->f_version;
3870 file->f_version = 0;
3871 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
3872 task;
3873 task = next_tid(task), ctx->pos++) {
3874 char name[10 + 1];
3875 unsigned int len;
3876
3877 tid = task_pid_nr_ns(task, ns);
3878 if (!tid)
3879 continue; /* The task has just exited. */
3880 len = snprintf(name, sizeof(name), "%u", tid);
3881 if (!proc_fill_cache(file, ctx, name, len,
3882 proc_task_instantiate, task, NULL)) {
3883 /* returning this tgid failed, save it as the first
3884 * pid for the next readir call */
3885 file->f_version = (u64)tid;
3886 put_task_struct(task);
3887 break;
3888 }
3889 }
3890
3891 return 0;
3892}
3893
3894static int proc_task_getattr(struct user_namespace *mnt_userns,
3895 const struct path *path, struct kstat *stat,
3896 u32 request_mask, unsigned int query_flags)
3897{
3898 struct inode *inode = d_inode(path->dentry);
3899 struct task_struct *p = get_proc_task(inode);
3900 generic_fillattr(&init_user_ns, inode, stat);
3901
3902 if (p) {
3903 stat->nlink += get_nr_threads(p);
3904 put_task_struct(p);
3905 }
3906
3907 return 0;
3908}
3909
3910static const struct inode_operations proc_task_inode_operations = {
3911 .lookup = proc_task_lookup,
3912 .getattr = proc_task_getattr,
3913 .setattr = proc_setattr,
3914 .permission = proc_pid_permission,
3915};
3916
3917static const struct file_operations proc_task_operations = {
3918 .read = generic_read_dir,
3919 .iterate_shared = proc_task_readdir,
3920 .llseek = generic_file_llseek,
3921};
3922
3923void __init set_proc_pid_nlink(void)
3924{
3925 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3926 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3927}
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#include <trace/events/oom.h>
98#include "internal.h"
99#include "fd.h"
100
101#include "../../lib/kstrtox.h"
102
103/* NOTE:
104 * Implementing inode permission operations in /proc is almost
105 * certainly an error. Permission checks need to happen during
106 * each system call not at open time. The reason is that most of
107 * what we wish to check for permissions in /proc varies at runtime.
108 *
109 * The classic example of a problem is opening file descriptors
110 * in /proc for a task before it execs a suid executable.
111 */
112
113static u8 nlink_tid __ro_after_init;
114static u8 nlink_tgid __ro_after_init;
115
116struct pid_entry {
117 const char *name;
118 unsigned int len;
119 umode_t mode;
120 const struct inode_operations *iop;
121 const struct file_operations *fop;
122 union proc_op op;
123};
124
125#define NOD(NAME, MODE, IOP, FOP, OP) { \
126 .name = (NAME), \
127 .len = sizeof(NAME) - 1, \
128 .mode = MODE, \
129 .iop = IOP, \
130 .fop = FOP, \
131 .op = OP, \
132}
133
134#define DIR(NAME, MODE, iops, fops) \
135 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
136#define LNK(NAME, get_link) \
137 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
138 &proc_pid_link_inode_operations, NULL, \
139 { .proc_get_link = get_link } )
140#define REG(NAME, MODE, fops) \
141 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
142#define ONE(NAME, MODE, show) \
143 NOD(NAME, (S_IFREG|(MODE)), \
144 NULL, &proc_single_file_operations, \
145 { .proc_show = show } )
146
147/*
148 * Count the number of hardlinks for the pid_entry table, excluding the .
149 * and .. links.
150 */
151static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,
152 unsigned int n)
153{
154 unsigned int i;
155 unsigned int count;
156
157 count = 2;
158 for (i = 0; i < n; ++i) {
159 if (S_ISDIR(entries[i].mode))
160 ++count;
161 }
162
163 return count;
164}
165
166static int get_task_root(struct task_struct *task, struct path *root)
167{
168 int result = -ENOENT;
169
170 task_lock(task);
171 if (task->fs) {
172 get_fs_root(task->fs, root);
173 result = 0;
174 }
175 task_unlock(task);
176 return result;
177}
178
179static int proc_cwd_link(struct dentry *dentry, struct path *path)
180{
181 struct task_struct *task = get_proc_task(d_inode(dentry));
182 int result = -ENOENT;
183
184 if (task) {
185 task_lock(task);
186 if (task->fs) {
187 get_fs_pwd(task->fs, path);
188 result = 0;
189 }
190 task_unlock(task);
191 put_task_struct(task);
192 }
193 return result;
194}
195
196static int proc_root_link(struct dentry *dentry, struct path *path)
197{
198 struct task_struct *task = get_proc_task(d_inode(dentry));
199 int result = -ENOENT;
200
201 if (task) {
202 result = get_task_root(task, path);
203 put_task_struct(task);
204 }
205 return result;
206}
207
208static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
209 size_t _count, loff_t *pos)
210{
211 struct task_struct *tsk;
212 struct mm_struct *mm;
213 char *page;
214 unsigned long count = _count;
215 unsigned long arg_start, arg_end, env_start, env_end;
216 unsigned long len1, len2, len;
217 unsigned long p;
218 char c;
219 ssize_t rv;
220
221 BUG_ON(*pos < 0);
222
223 tsk = get_proc_task(file_inode(file));
224 if (!tsk)
225 return -ESRCH;
226 mm = get_task_mm(tsk);
227 put_task_struct(tsk);
228 if (!mm)
229 return 0;
230 /* Check if process spawned far enough to have cmdline. */
231 if (!mm->env_end) {
232 rv = 0;
233 goto out_mmput;
234 }
235
236 page = (char *)__get_free_page(GFP_KERNEL);
237 if (!page) {
238 rv = -ENOMEM;
239 goto out_mmput;
240 }
241
242 down_read(&mm->mmap_sem);
243 arg_start = mm->arg_start;
244 arg_end = mm->arg_end;
245 env_start = mm->env_start;
246 env_end = mm->env_end;
247 up_read(&mm->mmap_sem);
248
249 BUG_ON(arg_start > arg_end);
250 BUG_ON(env_start > env_end);
251
252 len1 = arg_end - arg_start;
253 len2 = env_end - env_start;
254
255 /* Empty ARGV. */
256 if (len1 == 0) {
257 rv = 0;
258 goto out_free_page;
259 }
260 /*
261 * Inherently racy -- command line shares address space
262 * with code and data.
263 */
264 rv = access_remote_vm(mm, arg_end - 1, &c, 1, FOLL_ANON);
265 if (rv <= 0)
266 goto out_free_page;
267
268 rv = 0;
269
270 if (c == '\0') {
271 /* Command line (set of strings) occupies whole ARGV. */
272 if (len1 <= *pos)
273 goto out_free_page;
274
275 p = arg_start + *pos;
276 len = len1 - *pos;
277 while (count > 0 && len > 0) {
278 unsigned int _count;
279 int nr_read;
280
281 _count = min3(count, len, PAGE_SIZE);
282 nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
283 if (nr_read < 0)
284 rv = nr_read;
285 if (nr_read <= 0)
286 goto out_free_page;
287
288 if (copy_to_user(buf, page, nr_read)) {
289 rv = -EFAULT;
290 goto out_free_page;
291 }
292
293 p += nr_read;
294 len -= nr_read;
295 buf += nr_read;
296 count -= nr_read;
297 rv += nr_read;
298 }
299 } else {
300 /*
301 * Command line (1 string) occupies ARGV and
302 * extends into ENVP.
303 */
304 struct {
305 unsigned long p;
306 unsigned long len;
307 } cmdline[2] = {
308 { .p = arg_start, .len = len1 },
309 { .p = env_start, .len = len2 },
310 };
311 loff_t pos1 = *pos;
312 unsigned int i;
313
314 i = 0;
315 while (i < 2 && pos1 >= cmdline[i].len) {
316 pos1 -= cmdline[i].len;
317 i++;
318 }
319 while (i < 2) {
320 p = cmdline[i].p + pos1;
321 len = cmdline[i].len - pos1;
322 while (count > 0 && len > 0) {
323 unsigned int _count, l;
324 int nr_read;
325 bool final;
326
327 _count = min3(count, len, PAGE_SIZE);
328 nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
329 if (nr_read < 0)
330 rv = nr_read;
331 if (nr_read <= 0)
332 goto out_free_page;
333
334 /*
335 * Command line can be shorter than whole ARGV
336 * even if last "marker" byte says it is not.
337 */
338 final = false;
339 l = strnlen(page, nr_read);
340 if (l < nr_read) {
341 nr_read = l;
342 final = true;
343 }
344
345 if (copy_to_user(buf, page, nr_read)) {
346 rv = -EFAULT;
347 goto out_free_page;
348 }
349
350 p += nr_read;
351 len -= nr_read;
352 buf += nr_read;
353 count -= nr_read;
354 rv += nr_read;
355
356 if (final)
357 goto out_free_page;
358 }
359
360 /* Only first chunk can be read partially. */
361 pos1 = 0;
362 i++;
363 }
364 }
365
366out_free_page:
367 free_page((unsigned long)page);
368out_mmput:
369 mmput(mm);
370 if (rv > 0)
371 *pos += rv;
372 return rv;
373}
374
375static const struct file_operations proc_pid_cmdline_ops = {
376 .read = proc_pid_cmdline_read,
377 .llseek = generic_file_llseek,
378};
379
380#ifdef CONFIG_KALLSYMS
381/*
382 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
383 * Returns the resolved symbol. If that fails, simply return the address.
384 */
385static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
386 struct pid *pid, struct task_struct *task)
387{
388 unsigned long wchan;
389 char symname[KSYM_NAME_LEN];
390
391 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
392 goto print0;
393
394 wchan = get_wchan(task);
395 if (wchan && !lookup_symbol_name(wchan, symname)) {
396 seq_puts(m, symname);
397 return 0;
398 }
399
400print0:
401 seq_putc(m, '0');
402 return 0;
403}
404#endif /* CONFIG_KALLSYMS */
405
406static 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
418static 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
427static 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 */
463static 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
479static 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
510static int lstats_open(struct inode *inode, struct file *file)
511{
512 return single_open(file, lstats_show_proc, inode);
513}
514
515static 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
528static 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
538static 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
551struct limit_names {
552 const char *name;
553 const char *unit;
554};
555
556static 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 */
576static 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
618static 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 */
650static 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
666int 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 */
687static 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
699static 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
729static const struct inode_operations proc_def_inode_operations = {
730 .setattr = proc_setattr,
731};
732
733static 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
753static int proc_single_open(struct inode *inode, struct file *filp)
754{
755 return single_open(filp, proc_single_show, inode);
756}
757
758static 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
766struct 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
786static 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
797static 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
807static 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);
857free:
858 free_page((unsigned long) page);
859 return copied;
860}
861
862static 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
868static 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
874loff_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
890static 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
898static 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
906static int environ_open(struct inode *inode, struct file *file)
907{
908 return __mem_open(inode, file, PTRACE_MODE_READ);
909}
910
911static 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, FOLL_ANON);
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
969free:
970 free_page((unsigned long) page);
971 return ret;
972}
973
974static 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
981static int auxv_open(struct inode *inode, struct file *file)
982{
983 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
984}
985
986static 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
1001static 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
1008static 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
1028static 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 }
1110err_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 */
1126static 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);
1160out:
1161 return err < 0 ? err : count;
1162}
1163
1164static 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
1170static 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
1186static 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);
1211out:
1212 return err < 0 ? err : count;
1213}
1214
1215static 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
1223static 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
1240static 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
1279static const struct file_operations proc_loginuid_operations = {
1280 .read = proc_loginuid_read,
1281 .write = proc_loginuid_write,
1282 .llseek = generic_file_llseek,
1283};
1284
1285static 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
1301static 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
1308static 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
1326static 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
1356static 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
1362static 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
1382static 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
1399static 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 */
1410static 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
1426static ssize_t
1427sched_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
1443static int sched_open(struct inode *inode, struct file *filp)
1444{
1445 return single_open(filp, sched_show, inode);
1446}
1447
1448static 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 */
1462static 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
1477static ssize_t
1478sched_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
1510static 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
1523static 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
1533static 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
1559static 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
1577static int comm_open(struct inode *inode, struct file *filp)
1578{
1579 return single_open(filp, comm_show, inode);
1580}
1581
1582static 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
1590static 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
1609static 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;
1629out:
1630 return ERR_PTR(error);
1631}
1632
1633static 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
1657static 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);
1673out:
1674 return error;
1675}
1676
1677const 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
1686void 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 if (unlikely(task->flags & PF_KTHREAD)) {
1697 *ruid = GLOBAL_ROOT_UID;
1698 *rgid = GLOBAL_ROOT_GID;
1699 return;
1700 }
1701
1702 /* Default to the tasks effective ownership */
1703 rcu_read_lock();
1704 cred = __task_cred(task);
1705 uid = cred->euid;
1706 gid = cred->egid;
1707 rcu_read_unlock();
1708
1709 /*
1710 * Before the /proc/pid/status file was created the only way to read
1711 * the effective uid of a /process was to stat /proc/pid. Reading
1712 * /proc/pid/status is slow enough that procps and other packages
1713 * kept stating /proc/pid. To keep the rules in /proc simple I have
1714 * made this apply to all per process world readable and executable
1715 * directories.
1716 */
1717 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) {
1718 struct mm_struct *mm;
1719 task_lock(task);
1720 mm = task->mm;
1721 /* Make non-dumpable tasks owned by some root */
1722 if (mm) {
1723 if (get_dumpable(mm) != SUID_DUMP_USER) {
1724 struct user_namespace *user_ns = mm->user_ns;
1725
1726 uid = make_kuid(user_ns, 0);
1727 if (!uid_valid(uid))
1728 uid = GLOBAL_ROOT_UID;
1729
1730 gid = make_kgid(user_ns, 0);
1731 if (!gid_valid(gid))
1732 gid = GLOBAL_ROOT_GID;
1733 }
1734 } else {
1735 uid = GLOBAL_ROOT_UID;
1736 gid = GLOBAL_ROOT_GID;
1737 }
1738 task_unlock(task);
1739 }
1740 *ruid = uid;
1741 *rgid = gid;
1742}
1743
1744struct inode *proc_pid_make_inode(struct super_block * sb,
1745 struct task_struct *task, umode_t mode)
1746{
1747 struct inode * inode;
1748 struct proc_inode *ei;
1749
1750 /* We need a new inode */
1751
1752 inode = new_inode(sb);
1753 if (!inode)
1754 goto out;
1755
1756 /* Common stuff */
1757 ei = PROC_I(inode);
1758 inode->i_mode = mode;
1759 inode->i_ino = get_next_ino();
1760 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
1761 inode->i_op = &proc_def_inode_operations;
1762
1763 /*
1764 * grab the reference to task.
1765 */
1766 ei->pid = get_task_pid(task, PIDTYPE_PID);
1767 if (!ei->pid)
1768 goto out_unlock;
1769
1770 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1771 security_task_to_inode(task, inode);
1772
1773out:
1774 return inode;
1775
1776out_unlock:
1777 iput(inode);
1778 return NULL;
1779}
1780
1781int pid_getattr(const struct path *path, struct kstat *stat,
1782 u32 request_mask, unsigned int query_flags)
1783{
1784 struct inode *inode = d_inode(path->dentry);
1785 struct task_struct *task;
1786 struct pid_namespace *pid = path->dentry->d_sb->s_fs_info;
1787
1788 generic_fillattr(inode, stat);
1789
1790 rcu_read_lock();
1791 stat->uid = GLOBAL_ROOT_UID;
1792 stat->gid = GLOBAL_ROOT_GID;
1793 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1794 if (task) {
1795 if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) {
1796 rcu_read_unlock();
1797 /*
1798 * This doesn't prevent learning whether PID exists,
1799 * it only makes getattr() consistent with readdir().
1800 */
1801 return -ENOENT;
1802 }
1803 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid);
1804 }
1805 rcu_read_unlock();
1806 return 0;
1807}
1808
1809/* dentry stuff */
1810
1811/*
1812 * Exceptional case: normally we are not allowed to unhash a busy
1813 * directory. In this case, however, we can do it - no aliasing problems
1814 * due to the way we treat inodes.
1815 *
1816 * Rewrite the inode's ownerships here because the owning task may have
1817 * performed a setuid(), etc.
1818 *
1819 */
1820int pid_revalidate(struct dentry *dentry, unsigned int flags)
1821{
1822 struct inode *inode;
1823 struct task_struct *task;
1824
1825 if (flags & LOOKUP_RCU)
1826 return -ECHILD;
1827
1828 inode = d_inode(dentry);
1829 task = get_proc_task(inode);
1830
1831 if (task) {
1832 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
1833
1834 inode->i_mode &= ~(S_ISUID | S_ISGID);
1835 security_task_to_inode(task, inode);
1836 put_task_struct(task);
1837 return 1;
1838 }
1839 return 0;
1840}
1841
1842static inline bool proc_inode_is_dead(struct inode *inode)
1843{
1844 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
1845}
1846
1847int pid_delete_dentry(const struct dentry *dentry)
1848{
1849 /* Is the task we represent dead?
1850 * If so, then don't put the dentry on the lru list,
1851 * kill it immediately.
1852 */
1853 return proc_inode_is_dead(d_inode(dentry));
1854}
1855
1856const struct dentry_operations pid_dentry_operations =
1857{
1858 .d_revalidate = pid_revalidate,
1859 .d_delete = pid_delete_dentry,
1860};
1861
1862/* Lookups */
1863
1864/*
1865 * Fill a directory entry.
1866 *
1867 * If possible create the dcache entry and derive our inode number and
1868 * file type from dcache entry.
1869 *
1870 * Since all of the proc inode numbers are dynamically generated, the inode
1871 * numbers do not exist until the inode is cache. This means creating the
1872 * the dcache entry in readdir is necessary to keep the inode numbers
1873 * reported by readdir in sync with the inode numbers reported
1874 * by stat.
1875 */
1876bool proc_fill_cache(struct file *file, struct dir_context *ctx,
1877 const char *name, int len,
1878 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1879{
1880 struct dentry *child, *dir = file->f_path.dentry;
1881 struct qstr qname = QSTR_INIT(name, len);
1882 struct inode *inode;
1883 unsigned type;
1884 ino_t ino;
1885
1886 child = d_hash_and_lookup(dir, &qname);
1887 if (!child) {
1888 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
1889 child = d_alloc_parallel(dir, &qname, &wq);
1890 if (IS_ERR(child))
1891 goto end_instantiate;
1892 if (d_in_lookup(child)) {
1893 int err = instantiate(d_inode(dir), child, task, ptr);
1894 d_lookup_done(child);
1895 if (err < 0) {
1896 dput(child);
1897 goto end_instantiate;
1898 }
1899 }
1900 }
1901 inode = d_inode(child);
1902 ino = inode->i_ino;
1903 type = inode->i_mode >> 12;
1904 dput(child);
1905 return dir_emit(ctx, name, len, ino, type);
1906
1907end_instantiate:
1908 return dir_emit(ctx, name, len, 1, DT_UNKNOWN);
1909}
1910
1911/*
1912 * dname_to_vma_addr - maps a dentry name into two unsigned longs
1913 * which represent vma start and end addresses.
1914 */
1915static int dname_to_vma_addr(struct dentry *dentry,
1916 unsigned long *start, unsigned long *end)
1917{
1918 const char *str = dentry->d_name.name;
1919 unsigned long long sval, eval;
1920 unsigned int len;
1921
1922 if (str[0] == '0' && str[1] != '-')
1923 return -EINVAL;
1924 len = _parse_integer(str, 16, &sval);
1925 if (len & KSTRTOX_OVERFLOW)
1926 return -EINVAL;
1927 if (sval != (unsigned long)sval)
1928 return -EINVAL;
1929 str += len;
1930
1931 if (*str != '-')
1932 return -EINVAL;
1933 str++;
1934
1935 if (str[0] == '0' && str[1])
1936 return -EINVAL;
1937 len = _parse_integer(str, 16, &eval);
1938 if (len & KSTRTOX_OVERFLOW)
1939 return -EINVAL;
1940 if (eval != (unsigned long)eval)
1941 return -EINVAL;
1942 str += len;
1943
1944 if (*str != '\0')
1945 return -EINVAL;
1946
1947 *start = sval;
1948 *end = eval;
1949
1950 return 0;
1951}
1952
1953static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
1954{
1955 unsigned long vm_start, vm_end;
1956 bool exact_vma_exists = false;
1957 struct mm_struct *mm = NULL;
1958 struct task_struct *task;
1959 struct inode *inode;
1960 int status = 0;
1961
1962 if (flags & LOOKUP_RCU)
1963 return -ECHILD;
1964
1965 inode = d_inode(dentry);
1966 task = get_proc_task(inode);
1967 if (!task)
1968 goto out_notask;
1969
1970 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
1971 if (IS_ERR_OR_NULL(mm))
1972 goto out;
1973
1974 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
1975 down_read(&mm->mmap_sem);
1976 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
1977 up_read(&mm->mmap_sem);
1978 }
1979
1980 mmput(mm);
1981
1982 if (exact_vma_exists) {
1983 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1984
1985 security_task_to_inode(task, inode);
1986 status = 1;
1987 }
1988
1989out:
1990 put_task_struct(task);
1991
1992out_notask:
1993 return status;
1994}
1995
1996static const struct dentry_operations tid_map_files_dentry_operations = {
1997 .d_revalidate = map_files_d_revalidate,
1998 .d_delete = pid_delete_dentry,
1999};
2000
2001static int map_files_get_link(struct dentry *dentry, struct path *path)
2002{
2003 unsigned long vm_start, vm_end;
2004 struct vm_area_struct *vma;
2005 struct task_struct *task;
2006 struct mm_struct *mm;
2007 int rc;
2008
2009 rc = -ENOENT;
2010 task = get_proc_task(d_inode(dentry));
2011 if (!task)
2012 goto out;
2013
2014 mm = get_task_mm(task);
2015 put_task_struct(task);
2016 if (!mm)
2017 goto out;
2018
2019 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2020 if (rc)
2021 goto out_mmput;
2022
2023 rc = -ENOENT;
2024 down_read(&mm->mmap_sem);
2025 vma = find_exact_vma(mm, vm_start, vm_end);
2026 if (vma && vma->vm_file) {
2027 *path = vma->vm_file->f_path;
2028 path_get(path);
2029 rc = 0;
2030 }
2031 up_read(&mm->mmap_sem);
2032
2033out_mmput:
2034 mmput(mm);
2035out:
2036 return rc;
2037}
2038
2039struct map_files_info {
2040 unsigned long start;
2041 unsigned long end;
2042 fmode_t mode;
2043};
2044
2045/*
2046 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the
2047 * symlinks may be used to bypass permissions on ancestor directories in the
2048 * path to the file in question.
2049 */
2050static const char *
2051proc_map_files_get_link(struct dentry *dentry,
2052 struct inode *inode,
2053 struct delayed_call *done)
2054{
2055 if (!capable(CAP_SYS_ADMIN))
2056 return ERR_PTR(-EPERM);
2057
2058 return proc_pid_get_link(dentry, inode, done);
2059}
2060
2061/*
2062 * Identical to proc_pid_link_inode_operations except for get_link()
2063 */
2064static const struct inode_operations proc_map_files_link_inode_operations = {
2065 .readlink = proc_pid_readlink,
2066 .get_link = proc_map_files_get_link,
2067 .setattr = proc_setattr,
2068};
2069
2070static int
2071proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2072 struct task_struct *task, const void *ptr)
2073{
2074 fmode_t mode = (fmode_t)(unsigned long)ptr;
2075 struct proc_inode *ei;
2076 struct inode *inode;
2077
2078 inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK |
2079 ((mode & FMODE_READ ) ? S_IRUSR : 0) |
2080 ((mode & FMODE_WRITE) ? S_IWUSR : 0));
2081 if (!inode)
2082 return -ENOENT;
2083
2084 ei = PROC_I(inode);
2085 ei->op.proc_get_link = map_files_get_link;
2086
2087 inode->i_op = &proc_map_files_link_inode_operations;
2088 inode->i_size = 64;
2089
2090 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2091 d_add(dentry, inode);
2092
2093 return 0;
2094}
2095
2096static struct dentry *proc_map_files_lookup(struct inode *dir,
2097 struct dentry *dentry, unsigned int flags)
2098{
2099 unsigned long vm_start, vm_end;
2100 struct vm_area_struct *vma;
2101 struct task_struct *task;
2102 int result;
2103 struct mm_struct *mm;
2104
2105 result = -ENOENT;
2106 task = get_proc_task(dir);
2107 if (!task)
2108 goto out;
2109
2110 result = -EACCES;
2111 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2112 goto out_put_task;
2113
2114 result = -ENOENT;
2115 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2116 goto out_put_task;
2117
2118 mm = get_task_mm(task);
2119 if (!mm)
2120 goto out_put_task;
2121
2122 down_read(&mm->mmap_sem);
2123 vma = find_exact_vma(mm, vm_start, vm_end);
2124 if (!vma)
2125 goto out_no_vma;
2126
2127 if (vma->vm_file)
2128 result = proc_map_files_instantiate(dir, dentry, task,
2129 (void *)(unsigned long)vma->vm_file->f_mode);
2130
2131out_no_vma:
2132 up_read(&mm->mmap_sem);
2133 mmput(mm);
2134out_put_task:
2135 put_task_struct(task);
2136out:
2137 return ERR_PTR(result);
2138}
2139
2140static const struct inode_operations proc_map_files_inode_operations = {
2141 .lookup = proc_map_files_lookup,
2142 .permission = proc_fd_permission,
2143 .setattr = proc_setattr,
2144};
2145
2146static int
2147proc_map_files_readdir(struct file *file, struct dir_context *ctx)
2148{
2149 struct vm_area_struct *vma;
2150 struct task_struct *task;
2151 struct mm_struct *mm;
2152 unsigned long nr_files, pos, i;
2153 struct flex_array *fa = NULL;
2154 struct map_files_info info;
2155 struct map_files_info *p;
2156 int ret;
2157
2158 ret = -ENOENT;
2159 task = get_proc_task(file_inode(file));
2160 if (!task)
2161 goto out;
2162
2163 ret = -EACCES;
2164 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2165 goto out_put_task;
2166
2167 ret = 0;
2168 if (!dir_emit_dots(file, ctx))
2169 goto out_put_task;
2170
2171 mm = get_task_mm(task);
2172 if (!mm)
2173 goto out_put_task;
2174 down_read(&mm->mmap_sem);
2175
2176 nr_files = 0;
2177
2178 /*
2179 * We need two passes here:
2180 *
2181 * 1) Collect vmas of mapped files with mmap_sem taken
2182 * 2) Release mmap_sem and instantiate entries
2183 *
2184 * otherwise we get lockdep complained, since filldir()
2185 * routine might require mmap_sem taken in might_fault().
2186 */
2187
2188 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2189 if (vma->vm_file && ++pos > ctx->pos)
2190 nr_files++;
2191 }
2192
2193 if (nr_files) {
2194 fa = flex_array_alloc(sizeof(info), nr_files,
2195 GFP_KERNEL);
2196 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2197 GFP_KERNEL)) {
2198 ret = -ENOMEM;
2199 if (fa)
2200 flex_array_free(fa);
2201 up_read(&mm->mmap_sem);
2202 mmput(mm);
2203 goto out_put_task;
2204 }
2205 for (i = 0, vma = mm->mmap, pos = 2; vma;
2206 vma = vma->vm_next) {
2207 if (!vma->vm_file)
2208 continue;
2209 if (++pos <= ctx->pos)
2210 continue;
2211
2212 info.start = vma->vm_start;
2213 info.end = vma->vm_end;
2214 info.mode = vma->vm_file->f_mode;
2215 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2216 BUG();
2217 }
2218 }
2219 up_read(&mm->mmap_sem);
2220 mmput(mm);
2221
2222 for (i = 0; i < nr_files; i++) {
2223 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */
2224 unsigned int len;
2225
2226 p = flex_array_get(fa, i);
2227 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);
2228 if (!proc_fill_cache(file, ctx,
2229 buf, len,
2230 proc_map_files_instantiate,
2231 task,
2232 (void *)(unsigned long)p->mode))
2233 break;
2234 ctx->pos++;
2235 }
2236 if (fa)
2237 flex_array_free(fa);
2238
2239out_put_task:
2240 put_task_struct(task);
2241out:
2242 return ret;
2243}
2244
2245static const struct file_operations proc_map_files_operations = {
2246 .read = generic_read_dir,
2247 .iterate_shared = proc_map_files_readdir,
2248 .llseek = generic_file_llseek,
2249};
2250
2251#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
2252struct timers_private {
2253 struct pid *pid;
2254 struct task_struct *task;
2255 struct sighand_struct *sighand;
2256 struct pid_namespace *ns;
2257 unsigned long flags;
2258};
2259
2260static void *timers_start(struct seq_file *m, loff_t *pos)
2261{
2262 struct timers_private *tp = m->private;
2263
2264 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2265 if (!tp->task)
2266 return ERR_PTR(-ESRCH);
2267
2268 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2269 if (!tp->sighand)
2270 return ERR_PTR(-ESRCH);
2271
2272 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2273}
2274
2275static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2276{
2277 struct timers_private *tp = m->private;
2278 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2279}
2280
2281static void timers_stop(struct seq_file *m, void *v)
2282{
2283 struct timers_private *tp = m->private;
2284
2285 if (tp->sighand) {
2286 unlock_task_sighand(tp->task, &tp->flags);
2287 tp->sighand = NULL;
2288 }
2289
2290 if (tp->task) {
2291 put_task_struct(tp->task);
2292 tp->task = NULL;
2293 }
2294}
2295
2296static int show_timer(struct seq_file *m, void *v)
2297{
2298 struct k_itimer *timer;
2299 struct timers_private *tp = m->private;
2300 int notify;
2301 static const char * const nstr[] = {
2302 [SIGEV_SIGNAL] = "signal",
2303 [SIGEV_NONE] = "none",
2304 [SIGEV_THREAD] = "thread",
2305 };
2306
2307 timer = list_entry((struct list_head *)v, struct k_itimer, list);
2308 notify = timer->it_sigev_notify;
2309
2310 seq_printf(m, "ID: %d\n", timer->it_id);
2311 seq_printf(m, "signal: %d/%px\n",
2312 timer->sigq->info.si_signo,
2313 timer->sigq->info.si_value.sival_ptr);
2314 seq_printf(m, "notify: %s/%s.%d\n",
2315 nstr[notify & ~SIGEV_THREAD_ID],
2316 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2317 pid_nr_ns(timer->it_pid, tp->ns));
2318 seq_printf(m, "ClockID: %d\n", timer->it_clock);
2319
2320 return 0;
2321}
2322
2323static const struct seq_operations proc_timers_seq_ops = {
2324 .start = timers_start,
2325 .next = timers_next,
2326 .stop = timers_stop,
2327 .show = show_timer,
2328};
2329
2330static int proc_timers_open(struct inode *inode, struct file *file)
2331{
2332 struct timers_private *tp;
2333
2334 tp = __seq_open_private(file, &proc_timers_seq_ops,
2335 sizeof(struct timers_private));
2336 if (!tp)
2337 return -ENOMEM;
2338
2339 tp->pid = proc_pid(inode);
2340 tp->ns = inode->i_sb->s_fs_info;
2341 return 0;
2342}
2343
2344static const struct file_operations proc_timers_operations = {
2345 .open = proc_timers_open,
2346 .read = seq_read,
2347 .llseek = seq_lseek,
2348 .release = seq_release_private,
2349};
2350#endif
2351
2352static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2353 size_t count, loff_t *offset)
2354{
2355 struct inode *inode = file_inode(file);
2356 struct task_struct *p;
2357 u64 slack_ns;
2358 int err;
2359
2360 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2361 if (err < 0)
2362 return err;
2363
2364 p = get_proc_task(inode);
2365 if (!p)
2366 return -ESRCH;
2367
2368 if (p != current) {
2369 if (!capable(CAP_SYS_NICE)) {
2370 count = -EPERM;
2371 goto out;
2372 }
2373
2374 err = security_task_setscheduler(p);
2375 if (err) {
2376 count = err;
2377 goto out;
2378 }
2379 }
2380
2381 task_lock(p);
2382 if (slack_ns == 0)
2383 p->timer_slack_ns = p->default_timer_slack_ns;
2384 else
2385 p->timer_slack_ns = slack_ns;
2386 task_unlock(p);
2387
2388out:
2389 put_task_struct(p);
2390
2391 return count;
2392}
2393
2394static int timerslack_ns_show(struct seq_file *m, void *v)
2395{
2396 struct inode *inode = m->private;
2397 struct task_struct *p;
2398 int err = 0;
2399
2400 p = get_proc_task(inode);
2401 if (!p)
2402 return -ESRCH;
2403
2404 if (p != current) {
2405
2406 if (!capable(CAP_SYS_NICE)) {
2407 err = -EPERM;
2408 goto out;
2409 }
2410 err = security_task_getscheduler(p);
2411 if (err)
2412 goto out;
2413 }
2414
2415 task_lock(p);
2416 seq_printf(m, "%llu\n", p->timer_slack_ns);
2417 task_unlock(p);
2418
2419out:
2420 put_task_struct(p);
2421
2422 return err;
2423}
2424
2425static int timerslack_ns_open(struct inode *inode, struct file *filp)
2426{
2427 return single_open(filp, timerslack_ns_show, inode);
2428}
2429
2430static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2431 .open = timerslack_ns_open,
2432 .read = seq_read,
2433 .write = timerslack_ns_write,
2434 .llseek = seq_lseek,
2435 .release = single_release,
2436};
2437
2438static int proc_pident_instantiate(struct inode *dir,
2439 struct dentry *dentry, struct task_struct *task, const void *ptr)
2440{
2441 const struct pid_entry *p = ptr;
2442 struct inode *inode;
2443 struct proc_inode *ei;
2444
2445 inode = proc_pid_make_inode(dir->i_sb, task, p->mode);
2446 if (!inode)
2447 goto out;
2448
2449 ei = PROC_I(inode);
2450 if (S_ISDIR(inode->i_mode))
2451 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2452 if (p->iop)
2453 inode->i_op = p->iop;
2454 if (p->fop)
2455 inode->i_fop = p->fop;
2456 ei->op = p->op;
2457 d_set_d_op(dentry, &pid_dentry_operations);
2458 d_add(dentry, inode);
2459 /* Close the race of the process dying before we return the dentry */
2460 if (pid_revalidate(dentry, 0))
2461 return 0;
2462out:
2463 return -ENOENT;
2464}
2465
2466static struct dentry *proc_pident_lookup(struct inode *dir,
2467 struct dentry *dentry,
2468 const struct pid_entry *ents,
2469 unsigned int nents)
2470{
2471 int error;
2472 struct task_struct *task = get_proc_task(dir);
2473 const struct pid_entry *p, *last;
2474
2475 error = -ENOENT;
2476
2477 if (!task)
2478 goto out_no_task;
2479
2480 /*
2481 * Yes, it does not scale. And it should not. Don't add
2482 * new entries into /proc/<tgid>/ without very good reasons.
2483 */
2484 last = &ents[nents];
2485 for (p = ents; p < last; p++) {
2486 if (p->len != dentry->d_name.len)
2487 continue;
2488 if (!memcmp(dentry->d_name.name, p->name, p->len))
2489 break;
2490 }
2491 if (p >= last)
2492 goto out;
2493
2494 error = proc_pident_instantiate(dir, dentry, task, p);
2495out:
2496 put_task_struct(task);
2497out_no_task:
2498 return ERR_PTR(error);
2499}
2500
2501static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
2502 const struct pid_entry *ents, unsigned int nents)
2503{
2504 struct task_struct *task = get_proc_task(file_inode(file));
2505 const struct pid_entry *p;
2506
2507 if (!task)
2508 return -ENOENT;
2509
2510 if (!dir_emit_dots(file, ctx))
2511 goto out;
2512
2513 if (ctx->pos >= nents + 2)
2514 goto out;
2515
2516 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
2517 if (!proc_fill_cache(file, ctx, p->name, p->len,
2518 proc_pident_instantiate, task, p))
2519 break;
2520 ctx->pos++;
2521 }
2522out:
2523 put_task_struct(task);
2524 return 0;
2525}
2526
2527#ifdef CONFIG_SECURITY
2528static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2529 size_t count, loff_t *ppos)
2530{
2531 struct inode * inode = file_inode(file);
2532 char *p = NULL;
2533 ssize_t length;
2534 struct task_struct *task = get_proc_task(inode);
2535
2536 if (!task)
2537 return -ESRCH;
2538
2539 length = security_getprocattr(task,
2540 (char*)file->f_path.dentry->d_name.name,
2541 &p);
2542 put_task_struct(task);
2543 if (length > 0)
2544 length = simple_read_from_buffer(buf, count, ppos, p, length);
2545 kfree(p);
2546 return length;
2547}
2548
2549static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2550 size_t count, loff_t *ppos)
2551{
2552 struct inode * inode = file_inode(file);
2553 void *page;
2554 ssize_t length;
2555 struct task_struct *task = get_proc_task(inode);
2556
2557 length = -ESRCH;
2558 if (!task)
2559 goto out_no_task;
2560
2561 /* A task may only write its own attributes. */
2562 length = -EACCES;
2563 if (current != task)
2564 goto out;
2565
2566 if (count > PAGE_SIZE)
2567 count = PAGE_SIZE;
2568
2569 /* No partial writes. */
2570 length = -EINVAL;
2571 if (*ppos != 0)
2572 goto out;
2573
2574 page = memdup_user(buf, count);
2575 if (IS_ERR(page)) {
2576 length = PTR_ERR(page);
2577 goto out;
2578 }
2579
2580 /* Guard against adverse ptrace interaction */
2581 length = mutex_lock_interruptible(¤t->signal->cred_guard_mutex);
2582 if (length < 0)
2583 goto out_free;
2584
2585 length = security_setprocattr(file->f_path.dentry->d_name.name,
2586 page, count);
2587 mutex_unlock(¤t->signal->cred_guard_mutex);
2588out_free:
2589 kfree(page);
2590out:
2591 put_task_struct(task);
2592out_no_task:
2593 return length;
2594}
2595
2596static const struct file_operations proc_pid_attr_operations = {
2597 .read = proc_pid_attr_read,
2598 .write = proc_pid_attr_write,
2599 .llseek = generic_file_llseek,
2600};
2601
2602static const struct pid_entry attr_dir_stuff[] = {
2603 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2604 REG("prev", S_IRUGO, proc_pid_attr_operations),
2605 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2606 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2607 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2608 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2609};
2610
2611static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
2612{
2613 return proc_pident_readdir(file, ctx,
2614 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2615}
2616
2617static const struct file_operations proc_attr_dir_operations = {
2618 .read = generic_read_dir,
2619 .iterate_shared = proc_attr_dir_readdir,
2620 .llseek = generic_file_llseek,
2621};
2622
2623static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2624 struct dentry *dentry, unsigned int flags)
2625{
2626 return proc_pident_lookup(dir, dentry,
2627 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2628}
2629
2630static const struct inode_operations proc_attr_dir_inode_operations = {
2631 .lookup = proc_attr_dir_lookup,
2632 .getattr = pid_getattr,
2633 .setattr = proc_setattr,
2634};
2635
2636#endif
2637
2638#ifdef CONFIG_ELF_CORE
2639static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2640 size_t count, loff_t *ppos)
2641{
2642 struct task_struct *task = get_proc_task(file_inode(file));
2643 struct mm_struct *mm;
2644 char buffer[PROC_NUMBUF];
2645 size_t len;
2646 int ret;
2647
2648 if (!task)
2649 return -ESRCH;
2650
2651 ret = 0;
2652 mm = get_task_mm(task);
2653 if (mm) {
2654 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2655 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2656 MMF_DUMP_FILTER_SHIFT));
2657 mmput(mm);
2658 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2659 }
2660
2661 put_task_struct(task);
2662
2663 return ret;
2664}
2665
2666static ssize_t proc_coredump_filter_write(struct file *file,
2667 const char __user *buf,
2668 size_t count,
2669 loff_t *ppos)
2670{
2671 struct task_struct *task;
2672 struct mm_struct *mm;
2673 unsigned int val;
2674 int ret;
2675 int i;
2676 unsigned long mask;
2677
2678 ret = kstrtouint_from_user(buf, count, 0, &val);
2679 if (ret < 0)
2680 return ret;
2681
2682 ret = -ESRCH;
2683 task = get_proc_task(file_inode(file));
2684 if (!task)
2685 goto out_no_task;
2686
2687 mm = get_task_mm(task);
2688 if (!mm)
2689 goto out_no_mm;
2690 ret = 0;
2691
2692 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2693 if (val & mask)
2694 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2695 else
2696 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2697 }
2698
2699 mmput(mm);
2700 out_no_mm:
2701 put_task_struct(task);
2702 out_no_task:
2703 if (ret < 0)
2704 return ret;
2705 return count;
2706}
2707
2708static const struct file_operations proc_coredump_filter_operations = {
2709 .read = proc_coredump_filter_read,
2710 .write = proc_coredump_filter_write,
2711 .llseek = generic_file_llseek,
2712};
2713#endif
2714
2715#ifdef CONFIG_TASK_IO_ACCOUNTING
2716static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
2717{
2718 struct task_io_accounting acct = task->ioac;
2719 unsigned long flags;
2720 int result;
2721
2722 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2723 if (result)
2724 return result;
2725
2726 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
2727 result = -EACCES;
2728 goto out_unlock;
2729 }
2730
2731 if (whole && lock_task_sighand(task, &flags)) {
2732 struct task_struct *t = task;
2733
2734 task_io_accounting_add(&acct, &task->signal->ioac);
2735 while_each_thread(task, t)
2736 task_io_accounting_add(&acct, &t->ioac);
2737
2738 unlock_task_sighand(task, &flags);
2739 }
2740 seq_printf(m,
2741 "rchar: %llu\n"
2742 "wchar: %llu\n"
2743 "syscr: %llu\n"
2744 "syscw: %llu\n"
2745 "read_bytes: %llu\n"
2746 "write_bytes: %llu\n"
2747 "cancelled_write_bytes: %llu\n",
2748 (unsigned long long)acct.rchar,
2749 (unsigned long long)acct.wchar,
2750 (unsigned long long)acct.syscr,
2751 (unsigned long long)acct.syscw,
2752 (unsigned long long)acct.read_bytes,
2753 (unsigned long long)acct.write_bytes,
2754 (unsigned long long)acct.cancelled_write_bytes);
2755 result = 0;
2756
2757out_unlock:
2758 mutex_unlock(&task->signal->cred_guard_mutex);
2759 return result;
2760}
2761
2762static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2763 struct pid *pid, struct task_struct *task)
2764{
2765 return do_io_accounting(task, m, 0);
2766}
2767
2768static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2769 struct pid *pid, struct task_struct *task)
2770{
2771 return do_io_accounting(task, m, 1);
2772}
2773#endif /* CONFIG_TASK_IO_ACCOUNTING */
2774
2775#ifdef CONFIG_USER_NS
2776static int proc_id_map_open(struct inode *inode, struct file *file,
2777 const struct seq_operations *seq_ops)
2778{
2779 struct user_namespace *ns = NULL;
2780 struct task_struct *task;
2781 struct seq_file *seq;
2782 int ret = -EINVAL;
2783
2784 task = get_proc_task(inode);
2785 if (task) {
2786 rcu_read_lock();
2787 ns = get_user_ns(task_cred_xxx(task, user_ns));
2788 rcu_read_unlock();
2789 put_task_struct(task);
2790 }
2791 if (!ns)
2792 goto err;
2793
2794 ret = seq_open(file, seq_ops);
2795 if (ret)
2796 goto err_put_ns;
2797
2798 seq = file->private_data;
2799 seq->private = ns;
2800
2801 return 0;
2802err_put_ns:
2803 put_user_ns(ns);
2804err:
2805 return ret;
2806}
2807
2808static int proc_id_map_release(struct inode *inode, struct file *file)
2809{
2810 struct seq_file *seq = file->private_data;
2811 struct user_namespace *ns = seq->private;
2812 put_user_ns(ns);
2813 return seq_release(inode, file);
2814}
2815
2816static int proc_uid_map_open(struct inode *inode, struct file *file)
2817{
2818 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2819}
2820
2821static int proc_gid_map_open(struct inode *inode, struct file *file)
2822{
2823 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2824}
2825
2826static int proc_projid_map_open(struct inode *inode, struct file *file)
2827{
2828 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
2829}
2830
2831static const struct file_operations proc_uid_map_operations = {
2832 .open = proc_uid_map_open,
2833 .write = proc_uid_map_write,
2834 .read = seq_read,
2835 .llseek = seq_lseek,
2836 .release = proc_id_map_release,
2837};
2838
2839static const struct file_operations proc_gid_map_operations = {
2840 .open = proc_gid_map_open,
2841 .write = proc_gid_map_write,
2842 .read = seq_read,
2843 .llseek = seq_lseek,
2844 .release = proc_id_map_release,
2845};
2846
2847static const struct file_operations proc_projid_map_operations = {
2848 .open = proc_projid_map_open,
2849 .write = proc_projid_map_write,
2850 .read = seq_read,
2851 .llseek = seq_lseek,
2852 .release = proc_id_map_release,
2853};
2854
2855static int proc_setgroups_open(struct inode *inode, struct file *file)
2856{
2857 struct user_namespace *ns = NULL;
2858 struct task_struct *task;
2859 int ret;
2860
2861 ret = -ESRCH;
2862 task = get_proc_task(inode);
2863 if (task) {
2864 rcu_read_lock();
2865 ns = get_user_ns(task_cred_xxx(task, user_ns));
2866 rcu_read_unlock();
2867 put_task_struct(task);
2868 }
2869 if (!ns)
2870 goto err;
2871
2872 if (file->f_mode & FMODE_WRITE) {
2873 ret = -EACCES;
2874 if (!ns_capable(ns, CAP_SYS_ADMIN))
2875 goto err_put_ns;
2876 }
2877
2878 ret = single_open(file, &proc_setgroups_show, ns);
2879 if (ret)
2880 goto err_put_ns;
2881
2882 return 0;
2883err_put_ns:
2884 put_user_ns(ns);
2885err:
2886 return ret;
2887}
2888
2889static int proc_setgroups_release(struct inode *inode, struct file *file)
2890{
2891 struct seq_file *seq = file->private_data;
2892 struct user_namespace *ns = seq->private;
2893 int ret = single_release(inode, file);
2894 put_user_ns(ns);
2895 return ret;
2896}
2897
2898static const struct file_operations proc_setgroups_operations = {
2899 .open = proc_setgroups_open,
2900 .write = proc_setgroups_write,
2901 .read = seq_read,
2902 .llseek = seq_lseek,
2903 .release = proc_setgroups_release,
2904};
2905#endif /* CONFIG_USER_NS */
2906
2907static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2908 struct pid *pid, struct task_struct *task)
2909{
2910 int err = lock_trace(task);
2911 if (!err) {
2912 seq_printf(m, "%08x\n", task->personality);
2913 unlock_trace(task);
2914 }
2915 return err;
2916}
2917
2918#ifdef CONFIG_LIVEPATCH
2919static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns,
2920 struct pid *pid, struct task_struct *task)
2921{
2922 seq_printf(m, "%d\n", task->patch_state);
2923 return 0;
2924}
2925#endif /* CONFIG_LIVEPATCH */
2926
2927/*
2928 * Thread groups
2929 */
2930static const struct file_operations proc_task_operations;
2931static const struct inode_operations proc_task_inode_operations;
2932
2933static const struct pid_entry tgid_base_stuff[] = {
2934 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2935 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2936 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
2937 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2938 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
2939#ifdef CONFIG_NET
2940 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
2941#endif
2942 REG("environ", S_IRUSR, proc_environ_operations),
2943 REG("auxv", S_IRUSR, proc_auxv_operations),
2944 ONE("status", S_IRUGO, proc_pid_status),
2945 ONE("personality", S_IRUSR, proc_pid_personality),
2946 ONE("limits", S_IRUGO, proc_pid_limits),
2947#ifdef CONFIG_SCHED_DEBUG
2948 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2949#endif
2950#ifdef CONFIG_SCHED_AUTOGROUP
2951 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
2952#endif
2953 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2954#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2955 ONE("syscall", S_IRUSR, proc_pid_syscall),
2956#endif
2957 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
2958 ONE("stat", S_IRUGO, proc_tgid_stat),
2959 ONE("statm", S_IRUGO, proc_pid_statm),
2960 REG("maps", S_IRUGO, proc_pid_maps_operations),
2961#ifdef CONFIG_NUMA
2962 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
2963#endif
2964 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2965 LNK("cwd", proc_cwd_link),
2966 LNK("root", proc_root_link),
2967 LNK("exe", proc_exe_link),
2968 REG("mounts", S_IRUGO, proc_mounts_operations),
2969 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2970 REG("mountstats", S_IRUSR, proc_mountstats_operations),
2971#ifdef CONFIG_PROC_PAGE_MONITOR
2972 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2973 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
2974 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
2975 REG("pagemap", S_IRUSR, proc_pagemap_operations),
2976#endif
2977#ifdef CONFIG_SECURITY
2978 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
2979#endif
2980#ifdef CONFIG_KALLSYMS
2981 ONE("wchan", S_IRUGO, proc_pid_wchan),
2982#endif
2983#ifdef CONFIG_STACKTRACE
2984 ONE("stack", S_IRUSR, proc_pid_stack),
2985#endif
2986#ifdef CONFIG_SCHED_INFO
2987 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
2988#endif
2989#ifdef CONFIG_LATENCYTOP
2990 REG("latency", S_IRUGO, proc_lstats_operations),
2991#endif
2992#ifdef CONFIG_PROC_PID_CPUSET
2993 ONE("cpuset", S_IRUGO, proc_cpuset_show),
2994#endif
2995#ifdef CONFIG_CGROUPS
2996 ONE("cgroup", S_IRUGO, proc_cgroup_show),
2997#endif
2998 ONE("oom_score", S_IRUGO, proc_oom_score),
2999 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3000 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3001#ifdef CONFIG_AUDITSYSCALL
3002 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3003 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3004#endif
3005#ifdef CONFIG_FAULT_INJECTION
3006 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3007 REG("fail-nth", 0644, proc_fail_nth_operations),
3008#endif
3009#ifdef CONFIG_ELF_CORE
3010 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3011#endif
3012#ifdef CONFIG_TASK_IO_ACCOUNTING
3013 ONE("io", S_IRUSR, proc_tgid_io_accounting),
3014#endif
3015#ifdef CONFIG_USER_NS
3016 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3017 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3018 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3019 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3020#endif
3021#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
3022 REG("timers", S_IRUGO, proc_timers_operations),
3023#endif
3024 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
3025#ifdef CONFIG_LIVEPATCH
3026 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3027#endif
3028};
3029
3030static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
3031{
3032 return proc_pident_readdir(file, ctx,
3033 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3034}
3035
3036static const struct file_operations proc_tgid_base_operations = {
3037 .read = generic_read_dir,
3038 .iterate_shared = proc_tgid_base_readdir,
3039 .llseek = generic_file_llseek,
3040};
3041
3042static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3043{
3044 return proc_pident_lookup(dir, dentry,
3045 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3046}
3047
3048static const struct inode_operations proc_tgid_base_inode_operations = {
3049 .lookup = proc_tgid_base_lookup,
3050 .getattr = pid_getattr,
3051 .setattr = proc_setattr,
3052 .permission = proc_pid_permission,
3053};
3054
3055static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
3056{
3057 struct dentry *dentry, *leader, *dir;
3058 char buf[10 + 1];
3059 struct qstr name;
3060
3061 name.name = buf;
3062 name.len = snprintf(buf, sizeof(buf), "%u", pid);
3063 /* no ->d_hash() rejects on procfs */
3064 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
3065 if (dentry) {
3066 d_invalidate(dentry);
3067 dput(dentry);
3068 }
3069
3070 if (pid == tgid)
3071 return;
3072
3073 name.name = buf;
3074 name.len = snprintf(buf, sizeof(buf), "%u", tgid);
3075 leader = d_hash_and_lookup(mnt->mnt_root, &name);
3076 if (!leader)
3077 goto out;
3078
3079 name.name = "task";
3080 name.len = strlen(name.name);
3081 dir = d_hash_and_lookup(leader, &name);
3082 if (!dir)
3083 goto out_put_leader;
3084
3085 name.name = buf;
3086 name.len = snprintf(buf, sizeof(buf), "%u", pid);
3087 dentry = d_hash_and_lookup(dir, &name);
3088 if (dentry) {
3089 d_invalidate(dentry);
3090 dput(dentry);
3091 }
3092
3093 dput(dir);
3094out_put_leader:
3095 dput(leader);
3096out:
3097 return;
3098}
3099
3100/**
3101 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3102 * @task: task that should be flushed.
3103 *
3104 * When flushing dentries from proc, one needs to flush them from global
3105 * proc (proc_mnt) and from all the namespaces' procs this task was seen
3106 * in. This call is supposed to do all of this job.
3107 *
3108 * Looks in the dcache for
3109 * /proc/@pid
3110 * /proc/@tgid/task/@pid
3111 * if either directory is present flushes it and all of it'ts children
3112 * from the dcache.
3113 *
3114 * It is safe and reasonable to cache /proc entries for a task until
3115 * that task exits. After that they just clog up the dcache with
3116 * useless entries, possibly causing useful dcache entries to be
3117 * flushed instead. This routine is proved to flush those useless
3118 * dcache entries at process exit time.
3119 *
3120 * NOTE: This routine is just an optimization so it does not guarantee
3121 * that no dcache entries will exist at process exit time it
3122 * just makes it very unlikely that any will persist.
3123 */
3124
3125void proc_flush_task(struct task_struct *task)
3126{
3127 int i;
3128 struct pid *pid, *tgid;
3129 struct upid *upid;
3130
3131 pid = task_pid(task);
3132 tgid = task_tgid(task);
3133
3134 for (i = 0; i <= pid->level; i++) {
3135 upid = &pid->numbers[i];
3136 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
3137 tgid->numbers[i].nr);
3138 }
3139}
3140
3141static int proc_pid_instantiate(struct inode *dir,
3142 struct dentry * dentry,
3143 struct task_struct *task, const void *ptr)
3144{
3145 struct inode *inode;
3146
3147 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
3148 if (!inode)
3149 goto out;
3150
3151 inode->i_op = &proc_tgid_base_inode_operations;
3152 inode->i_fop = &proc_tgid_base_operations;
3153 inode->i_flags|=S_IMMUTABLE;
3154
3155 set_nlink(inode, nlink_tgid);
3156
3157 d_set_d_op(dentry, &pid_dentry_operations);
3158
3159 d_add(dentry, inode);
3160 /* Close the race of the process dying before we return the dentry */
3161 if (pid_revalidate(dentry, 0))
3162 return 0;
3163out:
3164 return -ENOENT;
3165}
3166
3167struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3168{
3169 int result = -ENOENT;
3170 struct task_struct *task;
3171 unsigned tgid;
3172 struct pid_namespace *ns;
3173
3174 tgid = name_to_int(&dentry->d_name);
3175 if (tgid == ~0U)
3176 goto out;
3177
3178 ns = dentry->d_sb->s_fs_info;
3179 rcu_read_lock();
3180 task = find_task_by_pid_ns(tgid, ns);
3181 if (task)
3182 get_task_struct(task);
3183 rcu_read_unlock();
3184 if (!task)
3185 goto out;
3186
3187 result = proc_pid_instantiate(dir, dentry, task, NULL);
3188 put_task_struct(task);
3189out:
3190 return ERR_PTR(result);
3191}
3192
3193/*
3194 * Find the first task with tgid >= tgid
3195 *
3196 */
3197struct tgid_iter {
3198 unsigned int tgid;
3199 struct task_struct *task;
3200};
3201static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3202{
3203 struct pid *pid;
3204
3205 if (iter.task)
3206 put_task_struct(iter.task);
3207 rcu_read_lock();
3208retry:
3209 iter.task = NULL;
3210 pid = find_ge_pid(iter.tgid, ns);
3211 if (pid) {
3212 iter.tgid = pid_nr_ns(pid, ns);
3213 iter.task = pid_task(pid, PIDTYPE_PID);
3214 /* What we to know is if the pid we have find is the
3215 * pid of a thread_group_leader. Testing for task
3216 * being a thread_group_leader is the obvious thing
3217 * todo but there is a window when it fails, due to
3218 * the pid transfer logic in de_thread.
3219 *
3220 * So we perform the straight forward test of seeing
3221 * if the pid we have found is the pid of a thread
3222 * group leader, and don't worry if the task we have
3223 * found doesn't happen to be a thread group leader.
3224 * As we don't care in the case of readdir.
3225 */
3226 if (!iter.task || !has_group_leader_pid(iter.task)) {
3227 iter.tgid += 1;
3228 goto retry;
3229 }
3230 get_task_struct(iter.task);
3231 }
3232 rcu_read_unlock();
3233 return iter;
3234}
3235
3236#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
3237
3238/* for the /proc/ directory itself, after non-process stuff has been done */
3239int proc_pid_readdir(struct file *file, struct dir_context *ctx)
3240{
3241 struct tgid_iter iter;
3242 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info;
3243 loff_t pos = ctx->pos;
3244
3245 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
3246 return 0;
3247
3248 if (pos == TGID_OFFSET - 2) {
3249 struct inode *inode = d_inode(ns->proc_self);
3250 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
3251 return 0;
3252 ctx->pos = pos = pos + 1;
3253 }
3254 if (pos == TGID_OFFSET - 1) {
3255 struct inode *inode = d_inode(ns->proc_thread_self);
3256 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3257 return 0;
3258 ctx->pos = pos = pos + 1;
3259 }
3260 iter.tgid = pos - TGID_OFFSET;
3261 iter.task = NULL;
3262 for (iter = next_tgid(ns, iter);
3263 iter.task;
3264 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3265 char name[10 + 1];
3266 int len;
3267
3268 cond_resched();
3269 if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE))
3270 continue;
3271
3272 len = snprintf(name, sizeof(name), "%u", iter.tgid);
3273 ctx->pos = iter.tgid + TGID_OFFSET;
3274 if (!proc_fill_cache(file, ctx, name, len,
3275 proc_pid_instantiate, iter.task, NULL)) {
3276 put_task_struct(iter.task);
3277 return 0;
3278 }
3279 }
3280 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
3281 return 0;
3282}
3283
3284/*
3285 * proc_tid_comm_permission is a special permission function exclusively
3286 * used for the node /proc/<pid>/task/<tid>/comm.
3287 * It bypasses generic permission checks in the case where a task of the same
3288 * task group attempts to access the node.
3289 * The rationale behind this is that glibc and bionic access this node for
3290 * cross thread naming (pthread_set/getname_np(!self)). However, if
3291 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3292 * which locks out the cross thread naming implementation.
3293 * This function makes sure that the node is always accessible for members of
3294 * same thread group.
3295 */
3296static int proc_tid_comm_permission(struct inode *inode, int mask)
3297{
3298 bool is_same_tgroup;
3299 struct task_struct *task;
3300
3301 task = get_proc_task(inode);
3302 if (!task)
3303 return -ESRCH;
3304 is_same_tgroup = same_thread_group(current, task);
3305 put_task_struct(task);
3306
3307 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3308 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3309 * read or written by the members of the corresponding
3310 * thread group.
3311 */
3312 return 0;
3313 }
3314
3315 return generic_permission(inode, mask);
3316}
3317
3318static const struct inode_operations proc_tid_comm_inode_operations = {
3319 .permission = proc_tid_comm_permission,
3320};
3321
3322/*
3323 * Tasks
3324 */
3325static const struct pid_entry tid_base_stuff[] = {
3326 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3327 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3328 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3329#ifdef CONFIG_NET
3330 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3331#endif
3332 REG("environ", S_IRUSR, proc_environ_operations),
3333 REG("auxv", S_IRUSR, proc_auxv_operations),
3334 ONE("status", S_IRUGO, proc_pid_status),
3335 ONE("personality", S_IRUSR, proc_pid_personality),
3336 ONE("limits", S_IRUGO, proc_pid_limits),
3337#ifdef CONFIG_SCHED_DEBUG
3338 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3339#endif
3340 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3341 &proc_tid_comm_inode_operations,
3342 &proc_pid_set_comm_operations, {}),
3343#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3344 ONE("syscall", S_IRUSR, proc_pid_syscall),
3345#endif
3346 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3347 ONE("stat", S_IRUGO, proc_tid_stat),
3348 ONE("statm", S_IRUGO, proc_pid_statm),
3349 REG("maps", S_IRUGO, proc_tid_maps_operations),
3350#ifdef CONFIG_PROC_CHILDREN
3351 REG("children", S_IRUGO, proc_tid_children_operations),
3352#endif
3353#ifdef CONFIG_NUMA
3354 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
3355#endif
3356 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3357 LNK("cwd", proc_cwd_link),
3358 LNK("root", proc_root_link),
3359 LNK("exe", proc_exe_link),
3360 REG("mounts", S_IRUGO, proc_mounts_operations),
3361 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3362#ifdef CONFIG_PROC_PAGE_MONITOR
3363 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3364 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
3365 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3366 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3367#endif
3368#ifdef CONFIG_SECURITY
3369 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3370#endif
3371#ifdef CONFIG_KALLSYMS
3372 ONE("wchan", S_IRUGO, proc_pid_wchan),
3373#endif
3374#ifdef CONFIG_STACKTRACE
3375 ONE("stack", S_IRUSR, proc_pid_stack),
3376#endif
3377#ifdef CONFIG_SCHED_INFO
3378 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3379#endif
3380#ifdef CONFIG_LATENCYTOP
3381 REG("latency", S_IRUGO, proc_lstats_operations),
3382#endif
3383#ifdef CONFIG_PROC_PID_CPUSET
3384 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3385#endif
3386#ifdef CONFIG_CGROUPS
3387 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3388#endif
3389 ONE("oom_score", S_IRUGO, proc_oom_score),
3390 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3391 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3392#ifdef CONFIG_AUDITSYSCALL
3393 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3394 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3395#endif
3396#ifdef CONFIG_FAULT_INJECTION
3397 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3398 REG("fail-nth", 0644, proc_fail_nth_operations),
3399#endif
3400#ifdef CONFIG_TASK_IO_ACCOUNTING
3401 ONE("io", S_IRUSR, proc_tid_io_accounting),
3402#endif
3403#ifdef CONFIG_USER_NS
3404 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3405 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3406 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3407 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3408#endif
3409#ifdef CONFIG_LIVEPATCH
3410 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3411#endif
3412};
3413
3414static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
3415{
3416 return proc_pident_readdir(file, ctx,
3417 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3418}
3419
3420static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3421{
3422 return proc_pident_lookup(dir, dentry,
3423 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3424}
3425
3426static const struct file_operations proc_tid_base_operations = {
3427 .read = generic_read_dir,
3428 .iterate_shared = proc_tid_base_readdir,
3429 .llseek = generic_file_llseek,
3430};
3431
3432static const struct inode_operations proc_tid_base_inode_operations = {
3433 .lookup = proc_tid_base_lookup,
3434 .getattr = pid_getattr,
3435 .setattr = proc_setattr,
3436};
3437
3438static int proc_task_instantiate(struct inode *dir,
3439 struct dentry *dentry, struct task_struct *task, const void *ptr)
3440{
3441 struct inode *inode;
3442 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
3443
3444 if (!inode)
3445 goto out;
3446 inode->i_op = &proc_tid_base_inode_operations;
3447 inode->i_fop = &proc_tid_base_operations;
3448 inode->i_flags|=S_IMMUTABLE;
3449
3450 set_nlink(inode, nlink_tid);
3451
3452 d_set_d_op(dentry, &pid_dentry_operations);
3453
3454 d_add(dentry, inode);
3455 /* Close the race of the process dying before we return the dentry */
3456 if (pid_revalidate(dentry, 0))
3457 return 0;
3458out:
3459 return -ENOENT;
3460}
3461
3462static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3463{
3464 int result = -ENOENT;
3465 struct task_struct *task;
3466 struct task_struct *leader = get_proc_task(dir);
3467 unsigned tid;
3468 struct pid_namespace *ns;
3469
3470 if (!leader)
3471 goto out_no_task;
3472
3473 tid = name_to_int(&dentry->d_name);
3474 if (tid == ~0U)
3475 goto out;
3476
3477 ns = dentry->d_sb->s_fs_info;
3478 rcu_read_lock();
3479 task = find_task_by_pid_ns(tid, ns);
3480 if (task)
3481 get_task_struct(task);
3482 rcu_read_unlock();
3483 if (!task)
3484 goto out;
3485 if (!same_thread_group(leader, task))
3486 goto out_drop_task;
3487
3488 result = proc_task_instantiate(dir, dentry, task, NULL);
3489out_drop_task:
3490 put_task_struct(task);
3491out:
3492 put_task_struct(leader);
3493out_no_task:
3494 return ERR_PTR(result);
3495}
3496
3497/*
3498 * Find the first tid of a thread group to return to user space.
3499 *
3500 * Usually this is just the thread group leader, but if the users
3501 * buffer was too small or there was a seek into the middle of the
3502 * directory we have more work todo.
3503 *
3504 * In the case of a short read we start with find_task_by_pid.
3505 *
3506 * In the case of a seek we start with the leader and walk nr
3507 * threads past it.
3508 */
3509static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3510 struct pid_namespace *ns)
3511{
3512 struct task_struct *pos, *task;
3513 unsigned long nr = f_pos;
3514
3515 if (nr != f_pos) /* 32bit overflow? */
3516 return NULL;
3517
3518 rcu_read_lock();
3519 task = pid_task(pid, PIDTYPE_PID);
3520 if (!task)
3521 goto fail;
3522
3523 /* Attempt to start with the tid of a thread */
3524 if (tid && nr) {
3525 pos = find_task_by_pid_ns(tid, ns);
3526 if (pos && same_thread_group(pos, task))
3527 goto found;
3528 }
3529
3530 /* If nr exceeds the number of threads there is nothing todo */
3531 if (nr >= get_nr_threads(task))
3532 goto fail;
3533
3534 /* If we haven't found our starting place yet start
3535 * with the leader and walk nr threads forward.
3536 */
3537 pos = task = task->group_leader;
3538 do {
3539 if (!nr--)
3540 goto found;
3541 } while_each_thread(task, pos);
3542fail:
3543 pos = NULL;
3544 goto out;
3545found:
3546 get_task_struct(pos);
3547out:
3548 rcu_read_unlock();
3549 return pos;
3550}
3551
3552/*
3553 * Find the next thread in the thread list.
3554 * Return NULL if there is an error or no next thread.
3555 *
3556 * The reference to the input task_struct is released.
3557 */
3558static struct task_struct *next_tid(struct task_struct *start)
3559{
3560 struct task_struct *pos = NULL;
3561 rcu_read_lock();
3562 if (pid_alive(start)) {
3563 pos = next_thread(start);
3564 if (thread_group_leader(pos))
3565 pos = NULL;
3566 else
3567 get_task_struct(pos);
3568 }
3569 rcu_read_unlock();
3570 put_task_struct(start);
3571 return pos;
3572}
3573
3574/* for the /proc/TGID/task/ directories */
3575static int proc_task_readdir(struct file *file, struct dir_context *ctx)
3576{
3577 struct inode *inode = file_inode(file);
3578 struct task_struct *task;
3579 struct pid_namespace *ns;
3580 int tid;
3581
3582 if (proc_inode_is_dead(inode))
3583 return -ENOENT;
3584
3585 if (!dir_emit_dots(file, ctx))
3586 return 0;
3587
3588 /* f_version caches the tgid value that the last readdir call couldn't
3589 * return. lseek aka telldir automagically resets f_version to 0.
3590 */
3591 ns = inode->i_sb->s_fs_info;
3592 tid = (int)file->f_version;
3593 file->f_version = 0;
3594 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
3595 task;
3596 task = next_tid(task), ctx->pos++) {
3597 char name[10 + 1];
3598 int len;
3599 tid = task_pid_nr_ns(task, ns);
3600 len = snprintf(name, sizeof(name), "%u", tid);
3601 if (!proc_fill_cache(file, ctx, name, len,
3602 proc_task_instantiate, task, NULL)) {
3603 /* returning this tgid failed, save it as the first
3604 * pid for the next readir call */
3605 file->f_version = (u64)tid;
3606 put_task_struct(task);
3607 break;
3608 }
3609 }
3610
3611 return 0;
3612}
3613
3614static int proc_task_getattr(const struct path *path, struct kstat *stat,
3615 u32 request_mask, unsigned int query_flags)
3616{
3617 struct inode *inode = d_inode(path->dentry);
3618 struct task_struct *p = get_proc_task(inode);
3619 generic_fillattr(inode, stat);
3620
3621 if (p) {
3622 stat->nlink += get_nr_threads(p);
3623 put_task_struct(p);
3624 }
3625
3626 return 0;
3627}
3628
3629static const struct inode_operations proc_task_inode_operations = {
3630 .lookup = proc_task_lookup,
3631 .getattr = proc_task_getattr,
3632 .setattr = proc_setattr,
3633 .permission = proc_pid_permission,
3634};
3635
3636static const struct file_operations proc_task_operations = {
3637 .read = generic_read_dir,
3638 .iterate_shared = proc_task_readdir,
3639 .llseek = generic_file_llseek,
3640};
3641
3642void __init set_proc_pid_nlink(void)
3643{
3644 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3645 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3646}