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