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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/proc/base.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 *
7 * proc base directory handling functions
8 *
9 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
10 * Instead of using magical inumbers to determine the kind of object
11 * we allocate and fill in-core inodes upon lookup. They don't even
12 * go into icache. We cache the reference to task_struct upon lookup too.
13 * Eventually it should become a filesystem in its own. We don't use the
14 * rest of procfs anymore.
15 *
16 *
17 * Changelog:
18 * 17-Jan-2005
19 * Allan Bezerra
20 * Bruna Moreira <bruna.moreira@indt.org.br>
21 * Edjard Mota <edjard.mota@indt.org.br>
22 * Ilias Biris <ilias.biris@indt.org.br>
23 * Mauricio Lin <mauricio.lin@indt.org.br>
24 *
25 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
26 *
27 * A new process specific entry (smaps) included in /proc. It shows the
28 * size of rss for each memory area. The maps entry lacks information
29 * about physical memory size (rss) for each mapped file, i.e.,
30 * rss information for executables and library files.
31 * This additional information is useful for any tools that need to know
32 * about physical memory consumption for a process specific library.
33 *
34 * Changelog:
35 * 21-Feb-2005
36 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
37 * Pud inclusion in the page table walking.
38 *
39 * ChangeLog:
40 * 10-Mar-2005
41 * 10LE Instituto Nokia de Tecnologia - INdT:
42 * A better way to walks through the page table as suggested by Hugh Dickins.
43 *
44 * Simo Piiroinen <simo.piiroinen@nokia.com>:
45 * Smaps information related to shared, private, clean and dirty pages.
46 *
47 * Paul Mundt <paul.mundt@nokia.com>:
48 * Overall revision about smaps.
49 */
50
51#include <linux/uaccess.h>
52
53#include <linux/errno.h>
54#include <linux/time.h>
55#include <linux/proc_fs.h>
56#include <linux/stat.h>
57#include <linux/task_io_accounting_ops.h>
58#include <linux/init.h>
59#include <linux/capability.h>
60#include <linux/file.h>
61#include <linux/fdtable.h>
62#include <linux/generic-radix-tree.h>
63#include <linux/string.h>
64#include <linux/seq_file.h>
65#include <linux/namei.h>
66#include <linux/mnt_namespace.h>
67#include <linux/mm.h>
68#include <linux/swap.h>
69#include <linux/rcupdate.h>
70#include <linux/kallsyms.h>
71#include <linux/stacktrace.h>
72#include <linux/resource.h>
73#include <linux/module.h>
74#include <linux/mount.h>
75#include <linux/security.h>
76#include <linux/ptrace.h>
77#include <linux/printk.h>
78#include <linux/cache.h>
79#include <linux/cgroup.h>
80#include <linux/cpuset.h>
81#include <linux/audit.h>
82#include <linux/poll.h>
83#include <linux/nsproxy.h>
84#include <linux/oom.h>
85#include <linux/elf.h>
86#include <linux/pid_namespace.h>
87#include <linux/user_namespace.h>
88#include <linux/fs_struct.h>
89#include <linux/slab.h>
90#include <linux/sched/autogroup.h>
91#include <linux/sched/mm.h>
92#include <linux/sched/coredump.h>
93#include <linux/sched/debug.h>
94#include <linux/sched/stat.h>
95#include <linux/posix-timers.h>
96#include <linux/time_namespace.h>
97#include <linux/resctrl.h>
98#include <linux/cn_proc.h>
99#include <linux/ksm.h>
100#include <uapi/linux/lsm.h>
101#include <trace/events/oom.h>
102#include "internal.h"
103#include "fd.h"
104
105#include "../../lib/kstrtox.h"
106
107/* NOTE:
108 * Implementing inode permission operations in /proc is almost
109 * certainly an error. Permission checks need to happen during
110 * each system call not at open time. The reason is that most of
111 * what we wish to check for permissions in /proc varies at runtime.
112 *
113 * The classic example of a problem is opening file descriptors
114 * in /proc for a task before it execs a suid executable.
115 */
116
117static u8 nlink_tid __ro_after_init;
118static u8 nlink_tgid __ro_after_init;
119
120struct pid_entry {
121 const char *name;
122 unsigned int len;
123 umode_t mode;
124 const struct inode_operations *iop;
125 const struct file_operations *fop;
126 union proc_op op;
127};
128
129#define NOD(NAME, MODE, IOP, FOP, OP) { \
130 .name = (NAME), \
131 .len = sizeof(NAME) - 1, \
132 .mode = MODE, \
133 .iop = IOP, \
134 .fop = FOP, \
135 .op = OP, \
136}
137
138#define DIR(NAME, MODE, iops, fops) \
139 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
140#define LNK(NAME, get_link) \
141 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
142 &proc_pid_link_inode_operations, NULL, \
143 { .proc_get_link = get_link } )
144#define REG(NAME, MODE, fops) \
145 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
146#define ONE(NAME, MODE, show) \
147 NOD(NAME, (S_IFREG|(MODE)), \
148 NULL, &proc_single_file_operations, \
149 { .proc_show = show } )
150#define ATTR(LSMID, NAME, MODE) \
151 NOD(NAME, (S_IFREG|(MODE)), \
152 NULL, &proc_pid_attr_operations, \
153 { .lsmid = LSMID })
154
155/*
156 * Count the number of hardlinks for the pid_entry table, excluding the .
157 * and .. links.
158 */
159static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,
160 unsigned int n)
161{
162 unsigned int i;
163 unsigned int count;
164
165 count = 2;
166 for (i = 0; i < n; ++i) {
167 if (S_ISDIR(entries[i].mode))
168 ++count;
169 }
170
171 return count;
172}
173
174static int get_task_root(struct task_struct *task, struct path *root)
175{
176 int result = -ENOENT;
177
178 task_lock(task);
179 if (task->fs) {
180 get_fs_root(task->fs, root);
181 result = 0;
182 }
183 task_unlock(task);
184 return result;
185}
186
187static int proc_cwd_link(struct dentry *dentry, struct path *path)
188{
189 struct task_struct *task = get_proc_task(d_inode(dentry));
190 int result = -ENOENT;
191
192 if (task) {
193 task_lock(task);
194 if (task->fs) {
195 get_fs_pwd(task->fs, path);
196 result = 0;
197 }
198 task_unlock(task);
199 put_task_struct(task);
200 }
201 return result;
202}
203
204static int proc_root_link(struct dentry *dentry, struct path *path)
205{
206 struct task_struct *task = get_proc_task(d_inode(dentry));
207 int result = -ENOENT;
208
209 if (task) {
210 result = get_task_root(task, path);
211 put_task_struct(task);
212 }
213 return result;
214}
215
216/*
217 * If the user used setproctitle(), we just get the string from
218 * user space at arg_start, and limit it to a maximum of one page.
219 */
220static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf,
221 size_t count, unsigned long pos,
222 unsigned long arg_start)
223{
224 char *page;
225 int ret, got;
226
227 if (pos >= PAGE_SIZE)
228 return 0;
229
230 page = (char *)__get_free_page(GFP_KERNEL);
231 if (!page)
232 return -ENOMEM;
233
234 ret = 0;
235 got = access_remote_vm(mm, arg_start, page, PAGE_SIZE, FOLL_ANON);
236 if (got > 0) {
237 int len = strnlen(page, got);
238
239 /* Include the NUL character if it was found */
240 if (len < got)
241 len++;
242
243 if (len > pos) {
244 len -= pos;
245 if (len > count)
246 len = count;
247 len -= copy_to_user(buf, page+pos, len);
248 if (!len)
249 len = -EFAULT;
250 ret = len;
251 }
252 }
253 free_page((unsigned long)page);
254 return ret;
255}
256
257static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf,
258 size_t count, loff_t *ppos)
259{
260 unsigned long arg_start, arg_end, env_start, env_end;
261 unsigned long pos, len;
262 char *page, c;
263
264 /* Check if process spawned far enough to have cmdline. */
265 if (!mm->env_end)
266 return 0;
267
268 spin_lock(&mm->arg_lock);
269 arg_start = mm->arg_start;
270 arg_end = mm->arg_end;
271 env_start = mm->env_start;
272 env_end = mm->env_end;
273 spin_unlock(&mm->arg_lock);
274
275 if (arg_start >= arg_end)
276 return 0;
277
278 /*
279 * We allow setproctitle() to overwrite the argument
280 * strings, and overflow past the original end. But
281 * only when it overflows into the environment area.
282 */
283 if (env_start != arg_end || env_end < env_start)
284 env_start = env_end = arg_end;
285 len = env_end - arg_start;
286
287 /* We're not going to care if "*ppos" has high bits set */
288 pos = *ppos;
289 if (pos >= len)
290 return 0;
291 if (count > len - pos)
292 count = len - pos;
293 if (!count)
294 return 0;
295
296 /*
297 * Magical special case: if the argv[] end byte is not
298 * zero, the user has overwritten it with setproctitle(3).
299 *
300 * Possible future enhancement: do this only once when
301 * pos is 0, and set a flag in the 'struct file'.
302 */
303 if (access_remote_vm(mm, arg_end-1, &c, 1, FOLL_ANON) == 1 && c)
304 return get_mm_proctitle(mm, buf, count, pos, arg_start);
305
306 /*
307 * For the non-setproctitle() case we limit things strictly
308 * to the [arg_start, arg_end[ range.
309 */
310 pos += arg_start;
311 if (pos < arg_start || pos >= arg_end)
312 return 0;
313 if (count > arg_end - pos)
314 count = arg_end - pos;
315
316 page = (char *)__get_free_page(GFP_KERNEL);
317 if (!page)
318 return -ENOMEM;
319
320 len = 0;
321 while (count) {
322 int got;
323 size_t size = min_t(size_t, PAGE_SIZE, count);
324
325 got = access_remote_vm(mm, pos, page, size, FOLL_ANON);
326 if (got <= 0)
327 break;
328 got -= copy_to_user(buf, page, got);
329 if (unlikely(!got)) {
330 if (!len)
331 len = -EFAULT;
332 break;
333 }
334 pos += got;
335 buf += got;
336 len += got;
337 count -= got;
338 }
339
340 free_page((unsigned long)page);
341 return len;
342}
343
344static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf,
345 size_t count, loff_t *pos)
346{
347 struct mm_struct *mm;
348 ssize_t ret;
349
350 mm = get_task_mm(tsk);
351 if (!mm)
352 return 0;
353
354 ret = get_mm_cmdline(mm, buf, count, pos);
355 mmput(mm);
356 return ret;
357}
358
359static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
360 size_t count, loff_t *pos)
361{
362 struct task_struct *tsk;
363 ssize_t ret;
364
365 BUG_ON(*pos < 0);
366
367 tsk = get_proc_task(file_inode(file));
368 if (!tsk)
369 return -ESRCH;
370 ret = get_task_cmdline(tsk, buf, count, pos);
371 put_task_struct(tsk);
372 if (ret > 0)
373 *pos += ret;
374 return ret;
375}
376
377static const struct file_operations proc_pid_cmdline_ops = {
378 .read = proc_pid_cmdline_read,
379 .llseek = generic_file_llseek,
380};
381
382#ifdef CONFIG_KALLSYMS
383/*
384 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
385 * Returns the resolved symbol. If that fails, simply return the address.
386 */
387static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
388 struct pid *pid, struct task_struct *task)
389{
390 unsigned long wchan;
391 char symname[KSYM_NAME_LEN];
392
393 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
394 goto print0;
395
396 wchan = get_wchan(task);
397 if (wchan && !lookup_symbol_name(wchan, symname)) {
398 seq_puts(m, symname);
399 return 0;
400 }
401
402print0:
403 seq_putc(m, '0');
404 return 0;
405}
406#endif /* CONFIG_KALLSYMS */
407
408static int lock_trace(struct task_struct *task)
409{
410 int err = down_read_killable(&task->signal->exec_update_lock);
411 if (err)
412 return err;
413 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
414 up_read(&task->signal->exec_update_lock);
415 return -EPERM;
416 }
417 return 0;
418}
419
420static void unlock_trace(struct task_struct *task)
421{
422 up_read(&task->signal->exec_update_lock);
423}
424
425#ifdef CONFIG_STACKTRACE
426
427#define MAX_STACK_TRACE_DEPTH 64
428
429static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
430 struct pid *pid, struct task_struct *task)
431{
432 unsigned long *entries;
433 int err;
434
435 /*
436 * The ability to racily run the kernel stack unwinder on a running task
437 * and then observe the unwinder output is scary; while it is useful for
438 * debugging kernel issues, it can also allow an attacker to leak kernel
439 * stack contents.
440 * Doing this in a manner that is at least safe from races would require
441 * some work to ensure that the remote task can not be scheduled; and
442 * even then, this would still expose the unwinder as local attack
443 * surface.
444 * Therefore, this interface is restricted to root.
445 */
446 if (!file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN))
447 return -EACCES;
448
449 entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries),
450 GFP_KERNEL);
451 if (!entries)
452 return -ENOMEM;
453
454 err = lock_trace(task);
455 if (!err) {
456 unsigned int i, nr_entries;
457
458 nr_entries = stack_trace_save_tsk(task, entries,
459 MAX_STACK_TRACE_DEPTH, 0);
460
461 for (i = 0; i < nr_entries; i++) {
462 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]);
463 }
464
465 unlock_trace(task);
466 }
467 kfree(entries);
468
469 return err;
470}
471#endif
472
473#ifdef CONFIG_SCHED_INFO
474/*
475 * Provides /proc/PID/schedstat
476 */
477static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
478 struct pid *pid, struct task_struct *task)
479{
480 if (unlikely(!sched_info_on()))
481 seq_puts(m, "0 0 0\n");
482 else
483 seq_printf(m, "%llu %llu %lu\n",
484 (unsigned long long)task->se.sum_exec_runtime,
485 (unsigned long long)task->sched_info.run_delay,
486 task->sched_info.pcount);
487
488 return 0;
489}
490#endif
491
492#ifdef CONFIG_LATENCYTOP
493static int lstats_show_proc(struct seq_file *m, void *v)
494{
495 int i;
496 struct inode *inode = m->private;
497 struct task_struct *task = get_proc_task(inode);
498
499 if (!task)
500 return -ESRCH;
501 seq_puts(m, "Latency Top version : v0.1\n");
502 for (i = 0; i < LT_SAVECOUNT; i++) {
503 struct latency_record *lr = &task->latency_record[i];
504 if (lr->backtrace[0]) {
505 int q;
506 seq_printf(m, "%i %li %li",
507 lr->count, lr->time, lr->max);
508 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
509 unsigned long bt = lr->backtrace[q];
510
511 if (!bt)
512 break;
513 seq_printf(m, " %ps", (void *)bt);
514 }
515 seq_putc(m, '\n');
516 }
517
518 }
519 put_task_struct(task);
520 return 0;
521}
522
523static int lstats_open(struct inode *inode, struct file *file)
524{
525 return single_open(file, lstats_show_proc, inode);
526}
527
528static ssize_t lstats_write(struct file *file, const char __user *buf,
529 size_t count, loff_t *offs)
530{
531 struct task_struct *task = get_proc_task(file_inode(file));
532
533 if (!task)
534 return -ESRCH;
535 clear_tsk_latency_tracing(task);
536 put_task_struct(task);
537
538 return count;
539}
540
541static const struct file_operations proc_lstats_operations = {
542 .open = lstats_open,
543 .read = seq_read,
544 .write = lstats_write,
545 .llseek = seq_lseek,
546 .release = single_release,
547};
548
549#endif
550
551static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
552 struct pid *pid, struct task_struct *task)
553{
554 unsigned long totalpages = totalram_pages() + total_swap_pages;
555 unsigned long points = 0;
556 long badness;
557
558 badness = oom_badness(task, totalpages);
559 /*
560 * Special case OOM_SCORE_ADJ_MIN for all others scale the
561 * badness value into [0, 2000] range which we have been
562 * exporting for a long time so userspace might depend on it.
563 */
564 if (badness != LONG_MIN)
565 points = (1000 + badness * 1000 / (long)totalpages) * 2 / 3;
566
567 seq_printf(m, "%lu\n", points);
568
569 return 0;
570}
571
572struct limit_names {
573 const char *name;
574 const char *unit;
575};
576
577static const struct limit_names lnames[RLIM_NLIMITS] = {
578 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
579 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
580 [RLIMIT_DATA] = {"Max data size", "bytes"},
581 [RLIMIT_STACK] = {"Max stack size", "bytes"},
582 [RLIMIT_CORE] = {"Max core file size", "bytes"},
583 [RLIMIT_RSS] = {"Max resident set", "bytes"},
584 [RLIMIT_NPROC] = {"Max processes", "processes"},
585 [RLIMIT_NOFILE] = {"Max open files", "files"},
586 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
587 [RLIMIT_AS] = {"Max address space", "bytes"},
588 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
589 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
590 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
591 [RLIMIT_NICE] = {"Max nice priority", NULL},
592 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
593 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
594};
595
596/* Display limits for a process */
597static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
598 struct pid *pid, struct task_struct *task)
599{
600 unsigned int i;
601 unsigned long flags;
602
603 struct rlimit rlim[RLIM_NLIMITS];
604
605 if (!lock_task_sighand(task, &flags))
606 return 0;
607 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
608 unlock_task_sighand(task, &flags);
609
610 /*
611 * print the file header
612 */
613 seq_puts(m, "Limit "
614 "Soft Limit "
615 "Hard Limit "
616 "Units \n");
617
618 for (i = 0; i < RLIM_NLIMITS; i++) {
619 if (rlim[i].rlim_cur == RLIM_INFINITY)
620 seq_printf(m, "%-25s %-20s ",
621 lnames[i].name, "unlimited");
622 else
623 seq_printf(m, "%-25s %-20lu ",
624 lnames[i].name, rlim[i].rlim_cur);
625
626 if (rlim[i].rlim_max == RLIM_INFINITY)
627 seq_printf(m, "%-20s ", "unlimited");
628 else
629 seq_printf(m, "%-20lu ", rlim[i].rlim_max);
630
631 if (lnames[i].unit)
632 seq_printf(m, "%-10s\n", lnames[i].unit);
633 else
634 seq_putc(m, '\n');
635 }
636
637 return 0;
638}
639
640#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
641static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
642 struct pid *pid, struct task_struct *task)
643{
644 struct syscall_info info;
645 u64 *args = &info.data.args[0];
646 int res;
647
648 res = lock_trace(task);
649 if (res)
650 return res;
651
652 if (task_current_syscall(task, &info))
653 seq_puts(m, "running\n");
654 else if (info.data.nr < 0)
655 seq_printf(m, "%d 0x%llx 0x%llx\n",
656 info.data.nr, info.sp, info.data.instruction_pointer);
657 else
658 seq_printf(m,
659 "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n",
660 info.data.nr,
661 args[0], args[1], args[2], args[3], args[4], args[5],
662 info.sp, info.data.instruction_pointer);
663 unlock_trace(task);
664
665 return 0;
666}
667#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
668
669/************************************************************************/
670/* Here the fs part begins */
671/************************************************************************/
672
673/* permission checks */
674static bool proc_fd_access_allowed(struct inode *inode)
675{
676 struct task_struct *task;
677 bool allowed = false;
678 /* Allow access to a task's file descriptors if it is us or we
679 * may use ptrace attach to the process and find out that
680 * information.
681 */
682 task = get_proc_task(inode);
683 if (task) {
684 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
685 put_task_struct(task);
686 }
687 return allowed;
688}
689
690int proc_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
691 struct iattr *attr)
692{
693 int error;
694 struct inode *inode = d_inode(dentry);
695
696 if (attr->ia_valid & ATTR_MODE)
697 return -EPERM;
698
699 error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
700 if (error)
701 return error;
702
703 setattr_copy(&nop_mnt_idmap, inode, attr);
704 return 0;
705}
706
707/*
708 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
709 * or euid/egid (for hide_pid_min=2)?
710 */
711static bool has_pid_permissions(struct proc_fs_info *fs_info,
712 struct task_struct *task,
713 enum proc_hidepid hide_pid_min)
714{
715 /*
716 * If 'hidpid' mount option is set force a ptrace check,
717 * we indicate that we are using a filesystem syscall
718 * by passing PTRACE_MODE_READ_FSCREDS
719 */
720 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE)
721 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
722
723 if (fs_info->hide_pid < hide_pid_min)
724 return true;
725 if (in_group_p(fs_info->pid_gid))
726 return true;
727 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
728}
729
730
731static int proc_pid_permission(struct mnt_idmap *idmap,
732 struct inode *inode, int mask)
733{
734 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
735 struct task_struct *task;
736 bool has_perms;
737
738 task = get_proc_task(inode);
739 if (!task)
740 return -ESRCH;
741 has_perms = has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS);
742 put_task_struct(task);
743
744 if (!has_perms) {
745 if (fs_info->hide_pid == HIDEPID_INVISIBLE) {
746 /*
747 * Let's make getdents(), stat(), and open()
748 * consistent with each other. If a process
749 * may not stat() a file, it shouldn't be seen
750 * in procfs at all.
751 */
752 return -ENOENT;
753 }
754
755 return -EPERM;
756 }
757 return generic_permission(&nop_mnt_idmap, inode, mask);
758}
759
760
761
762static const struct inode_operations proc_def_inode_operations = {
763 .setattr = proc_setattr,
764};
765
766static int proc_single_show(struct seq_file *m, void *v)
767{
768 struct inode *inode = m->private;
769 struct pid_namespace *ns = proc_pid_ns(inode->i_sb);
770 struct pid *pid = proc_pid(inode);
771 struct task_struct *task;
772 int ret;
773
774 task = get_pid_task(pid, PIDTYPE_PID);
775 if (!task)
776 return -ESRCH;
777
778 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
779
780 put_task_struct(task);
781 return ret;
782}
783
784static int proc_single_open(struct inode *inode, struct file *filp)
785{
786 return single_open(filp, proc_single_show, inode);
787}
788
789static const struct file_operations proc_single_file_operations = {
790 .open = proc_single_open,
791 .read = seq_read,
792 .llseek = seq_lseek,
793 .release = single_release,
794};
795
796
797struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
798{
799 struct task_struct *task = get_proc_task(inode);
800 struct mm_struct *mm = ERR_PTR(-ESRCH);
801
802 if (task) {
803 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
804 put_task_struct(task);
805
806 if (!IS_ERR_OR_NULL(mm)) {
807 /* ensure this mm_struct can't be freed */
808 mmgrab(mm);
809 /* but do not pin its memory */
810 mmput(mm);
811 }
812 }
813
814 return mm;
815}
816
817static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
818{
819 struct mm_struct *mm = proc_mem_open(inode, mode);
820
821 if (IS_ERR(mm))
822 return PTR_ERR(mm);
823
824 file->private_data = mm;
825 return 0;
826}
827
828static int mem_open(struct inode *inode, struct file *file)
829{
830 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
831
832 /* OK to pass negative loff_t, we can catch out-of-range */
833 file->f_mode |= FMODE_UNSIGNED_OFFSET;
834
835 return ret;
836}
837
838static ssize_t mem_rw(struct file *file, char __user *buf,
839 size_t count, loff_t *ppos, int write)
840{
841 struct mm_struct *mm = file->private_data;
842 unsigned long addr = *ppos;
843 ssize_t copied;
844 char *page;
845 unsigned int flags;
846
847 if (!mm)
848 return 0;
849
850 page = (char *)__get_free_page(GFP_KERNEL);
851 if (!page)
852 return -ENOMEM;
853
854 copied = 0;
855 if (!mmget_not_zero(mm))
856 goto free;
857
858 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0);
859
860 while (count > 0) {
861 size_t this_len = min_t(size_t, count, PAGE_SIZE);
862
863 if (write && copy_from_user(page, buf, this_len)) {
864 copied = -EFAULT;
865 break;
866 }
867
868 this_len = access_remote_vm(mm, addr, page, this_len, flags);
869 if (!this_len) {
870 if (!copied)
871 copied = -EIO;
872 break;
873 }
874
875 if (!write && copy_to_user(buf, page, this_len)) {
876 copied = -EFAULT;
877 break;
878 }
879
880 buf += this_len;
881 addr += this_len;
882 copied += this_len;
883 count -= this_len;
884 }
885 *ppos = addr;
886
887 mmput(mm);
888free:
889 free_page((unsigned long) page);
890 return copied;
891}
892
893static ssize_t mem_read(struct file *file, char __user *buf,
894 size_t count, loff_t *ppos)
895{
896 return mem_rw(file, buf, count, ppos, 0);
897}
898
899static ssize_t mem_write(struct file *file, const char __user *buf,
900 size_t count, loff_t *ppos)
901{
902 return mem_rw(file, (char __user*)buf, count, ppos, 1);
903}
904
905loff_t mem_lseek(struct file *file, loff_t offset, int orig)
906{
907 switch (orig) {
908 case 0:
909 file->f_pos = offset;
910 break;
911 case 1:
912 file->f_pos += offset;
913 break;
914 default:
915 return -EINVAL;
916 }
917 force_successful_syscall_return();
918 return file->f_pos;
919}
920
921static int mem_release(struct inode *inode, struct file *file)
922{
923 struct mm_struct *mm = file->private_data;
924 if (mm)
925 mmdrop(mm);
926 return 0;
927}
928
929static const struct file_operations proc_mem_operations = {
930 .llseek = mem_lseek,
931 .read = mem_read,
932 .write = mem_write,
933 .open = mem_open,
934 .release = mem_release,
935};
936
937static int environ_open(struct inode *inode, struct file *file)
938{
939 return __mem_open(inode, file, PTRACE_MODE_READ);
940}
941
942static ssize_t environ_read(struct file *file, char __user *buf,
943 size_t count, loff_t *ppos)
944{
945 char *page;
946 unsigned long src = *ppos;
947 int ret = 0;
948 struct mm_struct *mm = file->private_data;
949 unsigned long env_start, env_end;
950
951 /* Ensure the process spawned far enough to have an environment. */
952 if (!mm || !mm->env_end)
953 return 0;
954
955 page = (char *)__get_free_page(GFP_KERNEL);
956 if (!page)
957 return -ENOMEM;
958
959 ret = 0;
960 if (!mmget_not_zero(mm))
961 goto free;
962
963 spin_lock(&mm->arg_lock);
964 env_start = mm->env_start;
965 env_end = mm->env_end;
966 spin_unlock(&mm->arg_lock);
967
968 while (count > 0) {
969 size_t this_len, max_len;
970 int retval;
971
972 if (src >= (env_end - env_start))
973 break;
974
975 this_len = env_end - (env_start + src);
976
977 max_len = min_t(size_t, PAGE_SIZE, count);
978 this_len = min(max_len, this_len);
979
980 retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON);
981
982 if (retval <= 0) {
983 ret = retval;
984 break;
985 }
986
987 if (copy_to_user(buf, page, retval)) {
988 ret = -EFAULT;
989 break;
990 }
991
992 ret += retval;
993 src += retval;
994 buf += retval;
995 count -= retval;
996 }
997 *ppos = src;
998 mmput(mm);
999
1000free:
1001 free_page((unsigned long) page);
1002 return ret;
1003}
1004
1005static const struct file_operations proc_environ_operations = {
1006 .open = environ_open,
1007 .read = environ_read,
1008 .llseek = generic_file_llseek,
1009 .release = mem_release,
1010};
1011
1012static int auxv_open(struct inode *inode, struct file *file)
1013{
1014 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
1015}
1016
1017static ssize_t auxv_read(struct file *file, char __user *buf,
1018 size_t count, loff_t *ppos)
1019{
1020 struct mm_struct *mm = file->private_data;
1021 unsigned int nwords = 0;
1022
1023 if (!mm)
1024 return 0;
1025 do {
1026 nwords += 2;
1027 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1028 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,
1029 nwords * sizeof(mm->saved_auxv[0]));
1030}
1031
1032static const struct file_operations proc_auxv_operations = {
1033 .open = auxv_open,
1034 .read = auxv_read,
1035 .llseek = generic_file_llseek,
1036 .release = mem_release,
1037};
1038
1039static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1040 loff_t *ppos)
1041{
1042 struct task_struct *task = get_proc_task(file_inode(file));
1043 char buffer[PROC_NUMBUF];
1044 int oom_adj = OOM_ADJUST_MIN;
1045 size_t len;
1046
1047 if (!task)
1048 return -ESRCH;
1049 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1050 oom_adj = OOM_ADJUST_MAX;
1051 else
1052 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1053 OOM_SCORE_ADJ_MAX;
1054 put_task_struct(task);
1055 if (oom_adj > OOM_ADJUST_MAX)
1056 oom_adj = OOM_ADJUST_MAX;
1057 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1058 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1059}
1060
1061static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
1062{
1063 struct mm_struct *mm = NULL;
1064 struct task_struct *task;
1065 int err = 0;
1066
1067 task = get_proc_task(file_inode(file));
1068 if (!task)
1069 return -ESRCH;
1070
1071 mutex_lock(&oom_adj_mutex);
1072 if (legacy) {
1073 if (oom_adj < task->signal->oom_score_adj &&
1074 !capable(CAP_SYS_RESOURCE)) {
1075 err = -EACCES;
1076 goto err_unlock;
1077 }
1078 /*
1079 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1080 * /proc/pid/oom_score_adj instead.
1081 */
1082 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1083 current->comm, task_pid_nr(current), task_pid_nr(task),
1084 task_pid_nr(task));
1085 } else {
1086 if ((short)oom_adj < task->signal->oom_score_adj_min &&
1087 !capable(CAP_SYS_RESOURCE)) {
1088 err = -EACCES;
1089 goto err_unlock;
1090 }
1091 }
1092
1093 /*
1094 * Make sure we will check other processes sharing the mm if this is
1095 * not vfrok which wants its own oom_score_adj.
1096 * pin the mm so it doesn't go away and get reused after task_unlock
1097 */
1098 if (!task->vfork_done) {
1099 struct task_struct *p = find_lock_task_mm(task);
1100
1101 if (p) {
1102 if (test_bit(MMF_MULTIPROCESS, &p->mm->flags)) {
1103 mm = p->mm;
1104 mmgrab(mm);
1105 }
1106 task_unlock(p);
1107 }
1108 }
1109
1110 task->signal->oom_score_adj = oom_adj;
1111 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1112 task->signal->oom_score_adj_min = (short)oom_adj;
1113 trace_oom_score_adj_update(task);
1114
1115 if (mm) {
1116 struct task_struct *p;
1117
1118 rcu_read_lock();
1119 for_each_process(p) {
1120 if (same_thread_group(task, p))
1121 continue;
1122
1123 /* do not touch kernel threads or the global init */
1124 if (p->flags & PF_KTHREAD || is_global_init(p))
1125 continue;
1126
1127 task_lock(p);
1128 if (!p->vfork_done && process_shares_mm(p, mm)) {
1129 p->signal->oom_score_adj = oom_adj;
1130 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1131 p->signal->oom_score_adj_min = (short)oom_adj;
1132 }
1133 task_unlock(p);
1134 }
1135 rcu_read_unlock();
1136 mmdrop(mm);
1137 }
1138err_unlock:
1139 mutex_unlock(&oom_adj_mutex);
1140 put_task_struct(task);
1141 return err;
1142}
1143
1144/*
1145 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1146 * kernels. The effective policy is defined by oom_score_adj, which has a
1147 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1148 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1149 * Processes that become oom disabled via oom_adj will still be oom disabled
1150 * with this implementation.
1151 *
1152 * oom_adj cannot be removed since existing userspace binaries use it.
1153 */
1154static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1155 size_t count, loff_t *ppos)
1156{
1157 char buffer[PROC_NUMBUF] = {};
1158 int oom_adj;
1159 int err;
1160
1161 if (count > sizeof(buffer) - 1)
1162 count = sizeof(buffer) - 1;
1163 if (copy_from_user(buffer, buf, count)) {
1164 err = -EFAULT;
1165 goto out;
1166 }
1167
1168 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1169 if (err)
1170 goto out;
1171 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1172 oom_adj != OOM_DISABLE) {
1173 err = -EINVAL;
1174 goto out;
1175 }
1176
1177 /*
1178 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1179 * value is always attainable.
1180 */
1181 if (oom_adj == OOM_ADJUST_MAX)
1182 oom_adj = OOM_SCORE_ADJ_MAX;
1183 else
1184 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1185
1186 err = __set_oom_adj(file, oom_adj, true);
1187out:
1188 return err < 0 ? err : count;
1189}
1190
1191static const struct file_operations proc_oom_adj_operations = {
1192 .read = oom_adj_read,
1193 .write = oom_adj_write,
1194 .llseek = generic_file_llseek,
1195};
1196
1197static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1198 size_t count, loff_t *ppos)
1199{
1200 struct task_struct *task = get_proc_task(file_inode(file));
1201 char buffer[PROC_NUMBUF];
1202 short oom_score_adj = OOM_SCORE_ADJ_MIN;
1203 size_t len;
1204
1205 if (!task)
1206 return -ESRCH;
1207 oom_score_adj = task->signal->oom_score_adj;
1208 put_task_struct(task);
1209 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
1210 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1211}
1212
1213static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1214 size_t count, loff_t *ppos)
1215{
1216 char buffer[PROC_NUMBUF] = {};
1217 int oom_score_adj;
1218 int err;
1219
1220 if (count > sizeof(buffer) - 1)
1221 count = sizeof(buffer) - 1;
1222 if (copy_from_user(buffer, buf, count)) {
1223 err = -EFAULT;
1224 goto out;
1225 }
1226
1227 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1228 if (err)
1229 goto out;
1230 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1231 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1232 err = -EINVAL;
1233 goto out;
1234 }
1235
1236 err = __set_oom_adj(file, oom_score_adj, false);
1237out:
1238 return err < 0 ? err : count;
1239}
1240
1241static const struct file_operations proc_oom_score_adj_operations = {
1242 .read = oom_score_adj_read,
1243 .write = oom_score_adj_write,
1244 .llseek = default_llseek,
1245};
1246
1247#ifdef CONFIG_AUDIT
1248#define TMPBUFLEN 11
1249static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1250 size_t count, loff_t *ppos)
1251{
1252 struct inode * inode = file_inode(file);
1253 struct task_struct *task = get_proc_task(inode);
1254 ssize_t length;
1255 char tmpbuf[TMPBUFLEN];
1256
1257 if (!task)
1258 return -ESRCH;
1259 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1260 from_kuid(file->f_cred->user_ns,
1261 audit_get_loginuid(task)));
1262 put_task_struct(task);
1263 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1264}
1265
1266static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1267 size_t count, loff_t *ppos)
1268{
1269 struct inode * inode = file_inode(file);
1270 uid_t loginuid;
1271 kuid_t kloginuid;
1272 int rv;
1273
1274 /* Don't let kthreads write their own loginuid */
1275 if (current->flags & PF_KTHREAD)
1276 return -EPERM;
1277
1278 rcu_read_lock();
1279 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1280 rcu_read_unlock();
1281 return -EPERM;
1282 }
1283 rcu_read_unlock();
1284
1285 if (*ppos != 0) {
1286 /* No partial writes. */
1287 return -EINVAL;
1288 }
1289
1290 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1291 if (rv < 0)
1292 return rv;
1293
1294 /* is userspace tring to explicitly UNSET the loginuid? */
1295 if (loginuid == AUDIT_UID_UNSET) {
1296 kloginuid = INVALID_UID;
1297 } else {
1298 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
1299 if (!uid_valid(kloginuid))
1300 return -EINVAL;
1301 }
1302
1303 rv = audit_set_loginuid(kloginuid);
1304 if (rv < 0)
1305 return rv;
1306 return count;
1307}
1308
1309static const struct file_operations proc_loginuid_operations = {
1310 .read = proc_loginuid_read,
1311 .write = proc_loginuid_write,
1312 .llseek = generic_file_llseek,
1313};
1314
1315static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1316 size_t count, loff_t *ppos)
1317{
1318 struct inode * inode = file_inode(file);
1319 struct task_struct *task = get_proc_task(inode);
1320 ssize_t length;
1321 char tmpbuf[TMPBUFLEN];
1322
1323 if (!task)
1324 return -ESRCH;
1325 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1326 audit_get_sessionid(task));
1327 put_task_struct(task);
1328 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1329}
1330
1331static const struct file_operations proc_sessionid_operations = {
1332 .read = proc_sessionid_read,
1333 .llseek = generic_file_llseek,
1334};
1335#endif
1336
1337#ifdef CONFIG_FAULT_INJECTION
1338static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1339 size_t count, loff_t *ppos)
1340{
1341 struct task_struct *task = get_proc_task(file_inode(file));
1342 char buffer[PROC_NUMBUF];
1343 size_t len;
1344 int make_it_fail;
1345
1346 if (!task)
1347 return -ESRCH;
1348 make_it_fail = task->make_it_fail;
1349 put_task_struct(task);
1350
1351 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1352
1353 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1354}
1355
1356static ssize_t proc_fault_inject_write(struct file * file,
1357 const char __user * buf, size_t count, loff_t *ppos)
1358{
1359 struct task_struct *task;
1360 char buffer[PROC_NUMBUF] = {};
1361 int make_it_fail;
1362 int rv;
1363
1364 if (!capable(CAP_SYS_RESOURCE))
1365 return -EPERM;
1366
1367 if (count > sizeof(buffer) - 1)
1368 count = sizeof(buffer) - 1;
1369 if (copy_from_user(buffer, buf, count))
1370 return -EFAULT;
1371 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1372 if (rv < 0)
1373 return rv;
1374 if (make_it_fail < 0 || make_it_fail > 1)
1375 return -EINVAL;
1376
1377 task = get_proc_task(file_inode(file));
1378 if (!task)
1379 return -ESRCH;
1380 task->make_it_fail = make_it_fail;
1381 put_task_struct(task);
1382
1383 return count;
1384}
1385
1386static const struct file_operations proc_fault_inject_operations = {
1387 .read = proc_fault_inject_read,
1388 .write = proc_fault_inject_write,
1389 .llseek = generic_file_llseek,
1390};
1391
1392static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf,
1393 size_t count, loff_t *ppos)
1394{
1395 struct task_struct *task;
1396 int err;
1397 unsigned int n;
1398
1399 err = kstrtouint_from_user(buf, count, 0, &n);
1400 if (err)
1401 return err;
1402
1403 task = get_proc_task(file_inode(file));
1404 if (!task)
1405 return -ESRCH;
1406 task->fail_nth = n;
1407 put_task_struct(task);
1408
1409 return count;
1410}
1411
1412static ssize_t proc_fail_nth_read(struct file *file, char __user *buf,
1413 size_t count, loff_t *ppos)
1414{
1415 struct task_struct *task;
1416 char numbuf[PROC_NUMBUF];
1417 ssize_t len;
1418
1419 task = get_proc_task(file_inode(file));
1420 if (!task)
1421 return -ESRCH;
1422 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth);
1423 put_task_struct(task);
1424 return simple_read_from_buffer(buf, count, ppos, numbuf, len);
1425}
1426
1427static const struct file_operations proc_fail_nth_operations = {
1428 .read = proc_fail_nth_read,
1429 .write = proc_fail_nth_write,
1430};
1431#endif
1432
1433
1434#ifdef CONFIG_SCHED_DEBUG
1435/*
1436 * Print out various scheduling related per-task fields:
1437 */
1438static int sched_show(struct seq_file *m, void *v)
1439{
1440 struct inode *inode = m->private;
1441 struct pid_namespace *ns = proc_pid_ns(inode->i_sb);
1442 struct task_struct *p;
1443
1444 p = get_proc_task(inode);
1445 if (!p)
1446 return -ESRCH;
1447 proc_sched_show_task(p, ns, m);
1448
1449 put_task_struct(p);
1450
1451 return 0;
1452}
1453
1454static ssize_t
1455sched_write(struct file *file, const char __user *buf,
1456 size_t count, loff_t *offset)
1457{
1458 struct inode *inode = file_inode(file);
1459 struct task_struct *p;
1460
1461 p = get_proc_task(inode);
1462 if (!p)
1463 return -ESRCH;
1464 proc_sched_set_task(p);
1465
1466 put_task_struct(p);
1467
1468 return count;
1469}
1470
1471static int sched_open(struct inode *inode, struct file *filp)
1472{
1473 return single_open(filp, sched_show, inode);
1474}
1475
1476static const struct file_operations proc_pid_sched_operations = {
1477 .open = sched_open,
1478 .read = seq_read,
1479 .write = sched_write,
1480 .llseek = seq_lseek,
1481 .release = single_release,
1482};
1483
1484#endif
1485
1486#ifdef CONFIG_SCHED_AUTOGROUP
1487/*
1488 * Print out autogroup related information:
1489 */
1490static int sched_autogroup_show(struct seq_file *m, void *v)
1491{
1492 struct inode *inode = m->private;
1493 struct task_struct *p;
1494
1495 p = get_proc_task(inode);
1496 if (!p)
1497 return -ESRCH;
1498 proc_sched_autogroup_show_task(p, m);
1499
1500 put_task_struct(p);
1501
1502 return 0;
1503}
1504
1505static ssize_t
1506sched_autogroup_write(struct file *file, const char __user *buf,
1507 size_t count, loff_t *offset)
1508{
1509 struct inode *inode = file_inode(file);
1510 struct task_struct *p;
1511 char buffer[PROC_NUMBUF] = {};
1512 int nice;
1513 int err;
1514
1515 if (count > sizeof(buffer) - 1)
1516 count = sizeof(buffer) - 1;
1517 if (copy_from_user(buffer, buf, count))
1518 return -EFAULT;
1519
1520 err = kstrtoint(strstrip(buffer), 0, &nice);
1521 if (err < 0)
1522 return err;
1523
1524 p = get_proc_task(inode);
1525 if (!p)
1526 return -ESRCH;
1527
1528 err = proc_sched_autogroup_set_nice(p, nice);
1529 if (err)
1530 count = err;
1531
1532 put_task_struct(p);
1533
1534 return count;
1535}
1536
1537static int sched_autogroup_open(struct inode *inode, struct file *filp)
1538{
1539 int ret;
1540
1541 ret = single_open(filp, sched_autogroup_show, NULL);
1542 if (!ret) {
1543 struct seq_file *m = filp->private_data;
1544
1545 m->private = inode;
1546 }
1547 return ret;
1548}
1549
1550static const struct file_operations proc_pid_sched_autogroup_operations = {
1551 .open = sched_autogroup_open,
1552 .read = seq_read,
1553 .write = sched_autogroup_write,
1554 .llseek = seq_lseek,
1555 .release = single_release,
1556};
1557
1558#endif /* CONFIG_SCHED_AUTOGROUP */
1559
1560#ifdef CONFIG_TIME_NS
1561static int timens_offsets_show(struct seq_file *m, void *v)
1562{
1563 struct task_struct *p;
1564
1565 p = get_proc_task(file_inode(m->file));
1566 if (!p)
1567 return -ESRCH;
1568 proc_timens_show_offsets(p, m);
1569
1570 put_task_struct(p);
1571
1572 return 0;
1573}
1574
1575static ssize_t timens_offsets_write(struct file *file, const char __user *buf,
1576 size_t count, loff_t *ppos)
1577{
1578 struct inode *inode = file_inode(file);
1579 struct proc_timens_offset offsets[2];
1580 char *kbuf = NULL, *pos, *next_line;
1581 struct task_struct *p;
1582 int ret, noffsets;
1583
1584 /* Only allow < page size writes at the beginning of the file */
1585 if ((*ppos != 0) || (count >= PAGE_SIZE))
1586 return -EINVAL;
1587
1588 /* Slurp in the user data */
1589 kbuf = memdup_user_nul(buf, count);
1590 if (IS_ERR(kbuf))
1591 return PTR_ERR(kbuf);
1592
1593 /* Parse the user data */
1594 ret = -EINVAL;
1595 noffsets = 0;
1596 for (pos = kbuf; pos; pos = next_line) {
1597 struct proc_timens_offset *off = &offsets[noffsets];
1598 char clock[10];
1599 int err;
1600
1601 /* Find the end of line and ensure we don't look past it */
1602 next_line = strchr(pos, '\n');
1603 if (next_line) {
1604 *next_line = '\0';
1605 next_line++;
1606 if (*next_line == '\0')
1607 next_line = NULL;
1608 }
1609
1610 err = sscanf(pos, "%9s %lld %lu", clock,
1611 &off->val.tv_sec, &off->val.tv_nsec);
1612 if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC)
1613 goto out;
1614
1615 clock[sizeof(clock) - 1] = 0;
1616 if (strcmp(clock, "monotonic") == 0 ||
1617 strcmp(clock, __stringify(CLOCK_MONOTONIC)) == 0)
1618 off->clockid = CLOCK_MONOTONIC;
1619 else if (strcmp(clock, "boottime") == 0 ||
1620 strcmp(clock, __stringify(CLOCK_BOOTTIME)) == 0)
1621 off->clockid = CLOCK_BOOTTIME;
1622 else
1623 goto out;
1624
1625 noffsets++;
1626 if (noffsets == ARRAY_SIZE(offsets)) {
1627 if (next_line)
1628 count = next_line - kbuf;
1629 break;
1630 }
1631 }
1632
1633 ret = -ESRCH;
1634 p = get_proc_task(inode);
1635 if (!p)
1636 goto out;
1637 ret = proc_timens_set_offset(file, p, offsets, noffsets);
1638 put_task_struct(p);
1639 if (ret)
1640 goto out;
1641
1642 ret = count;
1643out:
1644 kfree(kbuf);
1645 return ret;
1646}
1647
1648static int timens_offsets_open(struct inode *inode, struct file *filp)
1649{
1650 return single_open(filp, timens_offsets_show, inode);
1651}
1652
1653static const struct file_operations proc_timens_offsets_operations = {
1654 .open = timens_offsets_open,
1655 .read = seq_read,
1656 .write = timens_offsets_write,
1657 .llseek = seq_lseek,
1658 .release = single_release,
1659};
1660#endif /* CONFIG_TIME_NS */
1661
1662static ssize_t comm_write(struct file *file, const char __user *buf,
1663 size_t count, loff_t *offset)
1664{
1665 struct inode *inode = file_inode(file);
1666 struct task_struct *p;
1667 char buffer[TASK_COMM_LEN] = {};
1668 const size_t maxlen = sizeof(buffer) - 1;
1669
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 proc_comm_connector(p);
1680 }
1681 else
1682 count = -EINVAL;
1683
1684 put_task_struct(p);
1685
1686 return count;
1687}
1688
1689static int comm_show(struct seq_file *m, void *v)
1690{
1691 struct inode *inode = m->private;
1692 struct task_struct *p;
1693
1694 p = get_proc_task(inode);
1695 if (!p)
1696 return -ESRCH;
1697
1698 proc_task_name(m, p, false);
1699 seq_putc(m, '\n');
1700
1701 put_task_struct(p);
1702
1703 return 0;
1704}
1705
1706static int comm_open(struct inode *inode, struct file *filp)
1707{
1708 return single_open(filp, comm_show, inode);
1709}
1710
1711static const struct file_operations proc_pid_set_comm_operations = {
1712 .open = comm_open,
1713 .read = seq_read,
1714 .write = comm_write,
1715 .llseek = seq_lseek,
1716 .release = single_release,
1717};
1718
1719static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1720{
1721 struct task_struct *task;
1722 struct file *exe_file;
1723
1724 task = get_proc_task(d_inode(dentry));
1725 if (!task)
1726 return -ENOENT;
1727 exe_file = get_task_exe_file(task);
1728 put_task_struct(task);
1729 if (exe_file) {
1730 *exe_path = exe_file->f_path;
1731 path_get(&exe_file->f_path);
1732 fput(exe_file);
1733 return 0;
1734 } else
1735 return -ENOENT;
1736}
1737
1738static const char *proc_pid_get_link(struct dentry *dentry,
1739 struct inode *inode,
1740 struct delayed_call *done)
1741{
1742 struct path path;
1743 int error = -EACCES;
1744
1745 if (!dentry)
1746 return ERR_PTR(-ECHILD);
1747
1748 /* Are we allowed to snoop on the tasks file descriptors? */
1749 if (!proc_fd_access_allowed(inode))
1750 goto out;
1751
1752 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1753 if (error)
1754 goto out;
1755
1756 error = nd_jump_link(&path);
1757out:
1758 return ERR_PTR(error);
1759}
1760
1761static int do_proc_readlink(const struct path *path, char __user *buffer, int buflen)
1762{
1763 char *tmp = kmalloc(PATH_MAX, GFP_KERNEL);
1764 char *pathname;
1765 int len;
1766
1767 if (!tmp)
1768 return -ENOMEM;
1769
1770 pathname = d_path(path, tmp, PATH_MAX);
1771 len = PTR_ERR(pathname);
1772 if (IS_ERR(pathname))
1773 goto out;
1774 len = tmp + PATH_MAX - 1 - pathname;
1775
1776 if (len > buflen)
1777 len = buflen;
1778 if (copy_to_user(buffer, pathname, len))
1779 len = -EFAULT;
1780 out:
1781 kfree(tmp);
1782 return len;
1783}
1784
1785static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1786{
1787 int error = -EACCES;
1788 struct inode *inode = d_inode(dentry);
1789 struct path path;
1790
1791 /* Are we allowed to snoop on the tasks file descriptors? */
1792 if (!proc_fd_access_allowed(inode))
1793 goto out;
1794
1795 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1796 if (error)
1797 goto out;
1798
1799 error = do_proc_readlink(&path, buffer, buflen);
1800 path_put(&path);
1801out:
1802 return error;
1803}
1804
1805const struct inode_operations proc_pid_link_inode_operations = {
1806 .readlink = proc_pid_readlink,
1807 .get_link = proc_pid_get_link,
1808 .setattr = proc_setattr,
1809};
1810
1811
1812/* building an inode */
1813
1814void task_dump_owner(struct task_struct *task, umode_t mode,
1815 kuid_t *ruid, kgid_t *rgid)
1816{
1817 /* Depending on the state of dumpable compute who should own a
1818 * proc file for a task.
1819 */
1820 const struct cred *cred;
1821 kuid_t uid;
1822 kgid_t gid;
1823
1824 if (unlikely(task->flags & PF_KTHREAD)) {
1825 *ruid = GLOBAL_ROOT_UID;
1826 *rgid = GLOBAL_ROOT_GID;
1827 return;
1828 }
1829
1830 /* Default to the tasks effective ownership */
1831 rcu_read_lock();
1832 cred = __task_cred(task);
1833 uid = cred->euid;
1834 gid = cred->egid;
1835 rcu_read_unlock();
1836
1837 /*
1838 * Before the /proc/pid/status file was created the only way to read
1839 * the effective uid of a /process was to stat /proc/pid. Reading
1840 * /proc/pid/status is slow enough that procps and other packages
1841 * kept stating /proc/pid. To keep the rules in /proc simple I have
1842 * made this apply to all per process world readable and executable
1843 * directories.
1844 */
1845 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) {
1846 struct mm_struct *mm;
1847 task_lock(task);
1848 mm = task->mm;
1849 /* Make non-dumpable tasks owned by some root */
1850 if (mm) {
1851 if (get_dumpable(mm) != SUID_DUMP_USER) {
1852 struct user_namespace *user_ns = mm->user_ns;
1853
1854 uid = make_kuid(user_ns, 0);
1855 if (!uid_valid(uid))
1856 uid = GLOBAL_ROOT_UID;
1857
1858 gid = make_kgid(user_ns, 0);
1859 if (!gid_valid(gid))
1860 gid = GLOBAL_ROOT_GID;
1861 }
1862 } else {
1863 uid = GLOBAL_ROOT_UID;
1864 gid = GLOBAL_ROOT_GID;
1865 }
1866 task_unlock(task);
1867 }
1868 *ruid = uid;
1869 *rgid = gid;
1870}
1871
1872void proc_pid_evict_inode(struct proc_inode *ei)
1873{
1874 struct pid *pid = ei->pid;
1875
1876 if (S_ISDIR(ei->vfs_inode.i_mode)) {
1877 spin_lock(&pid->lock);
1878 hlist_del_init_rcu(&ei->sibling_inodes);
1879 spin_unlock(&pid->lock);
1880 }
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 simple_inode_init_ts(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
1913 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1914 security_task_to_inode(task, inode);
1915
1916out:
1917 return inode;
1918
1919out_unlock:
1920 iput(inode);
1921 return NULL;
1922}
1923
1924/*
1925 * Generating an inode and adding it into @pid->inodes, so that task will
1926 * invalidate inode's dentry before being released.
1927 *
1928 * This helper is used for creating dir-type entries under '/proc' and
1929 * '/proc/<tgid>/task'. Other entries(eg. fd, stat) under '/proc/<tgid>'
1930 * can be released by invalidating '/proc/<tgid>' dentry.
1931 * In theory, dentries under '/proc/<tgid>/task' can also be released by
1932 * invalidating '/proc/<tgid>' dentry, we reserve it to handle single
1933 * thread exiting situation: Any one of threads should invalidate its
1934 * '/proc/<tgid>/task/<pid>' dentry before released.
1935 */
1936static struct inode *proc_pid_make_base_inode(struct super_block *sb,
1937 struct task_struct *task, umode_t mode)
1938{
1939 struct inode *inode;
1940 struct proc_inode *ei;
1941 struct pid *pid;
1942
1943 inode = proc_pid_make_inode(sb, task, mode);
1944 if (!inode)
1945 return NULL;
1946
1947 /* Let proc_flush_pid find this directory inode */
1948 ei = PROC_I(inode);
1949 pid = ei->pid;
1950 spin_lock(&pid->lock);
1951 hlist_add_head_rcu(&ei->sibling_inodes, &pid->inodes);
1952 spin_unlock(&pid->lock);
1953
1954 return inode;
1955}
1956
1957int pid_getattr(struct mnt_idmap *idmap, const struct path *path,
1958 struct kstat *stat, u32 request_mask, unsigned int query_flags)
1959{
1960 struct inode *inode = d_inode(path->dentry);
1961 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
1962 struct task_struct *task;
1963
1964 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
1965
1966 stat->uid = GLOBAL_ROOT_UID;
1967 stat->gid = GLOBAL_ROOT_GID;
1968 rcu_read_lock();
1969 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1970 if (task) {
1971 if (!has_pid_permissions(fs_info, task, HIDEPID_INVISIBLE)) {
1972 rcu_read_unlock();
1973 /*
1974 * This doesn't prevent learning whether PID exists,
1975 * it only makes getattr() consistent with readdir().
1976 */
1977 return -ENOENT;
1978 }
1979 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid);
1980 }
1981 rcu_read_unlock();
1982 return 0;
1983}
1984
1985/* dentry stuff */
1986
1987/*
1988 * Set <pid>/... inode ownership (can change due to setuid(), etc.)
1989 */
1990void pid_update_inode(struct task_struct *task, struct inode *inode)
1991{
1992 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
1993
1994 inode->i_mode &= ~(S_ISUID | S_ISGID);
1995 security_task_to_inode(task, inode);
1996}
1997
1998/*
1999 * Rewrite the inode's ownerships here because the owning task may have
2000 * performed a setuid(), etc.
2001 *
2002 */
2003static int pid_revalidate(struct dentry *dentry, unsigned int flags)
2004{
2005 struct inode *inode;
2006 struct task_struct *task;
2007 int ret = 0;
2008
2009 rcu_read_lock();
2010 inode = d_inode_rcu(dentry);
2011 if (!inode)
2012 goto out;
2013 task = pid_task(proc_pid(inode), PIDTYPE_PID);
2014
2015 if (task) {
2016 pid_update_inode(task, inode);
2017 ret = 1;
2018 }
2019out:
2020 rcu_read_unlock();
2021 return ret;
2022}
2023
2024static inline bool proc_inode_is_dead(struct inode *inode)
2025{
2026 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
2027}
2028
2029int pid_delete_dentry(const struct dentry *dentry)
2030{
2031 /* Is the task we represent dead?
2032 * If so, then don't put the dentry on the lru list,
2033 * kill it immediately.
2034 */
2035 return proc_inode_is_dead(d_inode(dentry));
2036}
2037
2038const struct dentry_operations pid_dentry_operations =
2039{
2040 .d_revalidate = pid_revalidate,
2041 .d_delete = pid_delete_dentry,
2042};
2043
2044/* Lookups */
2045
2046/*
2047 * Fill a directory entry.
2048 *
2049 * If possible create the dcache entry and derive our inode number and
2050 * file type from dcache entry.
2051 *
2052 * Since all of the proc inode numbers are dynamically generated, the inode
2053 * numbers do not exist until the inode is cache. This means creating
2054 * the dcache entry in readdir is necessary to keep the inode numbers
2055 * reported by readdir in sync with the inode numbers reported
2056 * by stat.
2057 */
2058bool proc_fill_cache(struct file *file, struct dir_context *ctx,
2059 const char *name, unsigned int len,
2060 instantiate_t instantiate, struct task_struct *task, const void *ptr)
2061{
2062 struct dentry *child, *dir = file->f_path.dentry;
2063 struct qstr qname = QSTR_INIT(name, len);
2064 struct inode *inode;
2065 unsigned type = DT_UNKNOWN;
2066 ino_t ino = 1;
2067
2068 child = d_hash_and_lookup(dir, &qname);
2069 if (!child) {
2070 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
2071 child = d_alloc_parallel(dir, &qname, &wq);
2072 if (IS_ERR(child))
2073 goto end_instantiate;
2074 if (d_in_lookup(child)) {
2075 struct dentry *res;
2076 res = instantiate(child, task, ptr);
2077 d_lookup_done(child);
2078 if (unlikely(res)) {
2079 dput(child);
2080 child = res;
2081 if (IS_ERR(child))
2082 goto end_instantiate;
2083 }
2084 }
2085 }
2086 inode = d_inode(child);
2087 ino = inode->i_ino;
2088 type = inode->i_mode >> 12;
2089 dput(child);
2090end_instantiate:
2091 return dir_emit(ctx, name, len, ino, type);
2092}
2093
2094/*
2095 * dname_to_vma_addr - maps a dentry name into two unsigned longs
2096 * which represent vma start and end addresses.
2097 */
2098static int dname_to_vma_addr(struct dentry *dentry,
2099 unsigned long *start, unsigned long *end)
2100{
2101 const char *str = dentry->d_name.name;
2102 unsigned long long sval, eval;
2103 unsigned int len;
2104
2105 if (str[0] == '0' && str[1] != '-')
2106 return -EINVAL;
2107 len = _parse_integer(str, 16, &sval);
2108 if (len & KSTRTOX_OVERFLOW)
2109 return -EINVAL;
2110 if (sval != (unsigned long)sval)
2111 return -EINVAL;
2112 str += len;
2113
2114 if (*str != '-')
2115 return -EINVAL;
2116 str++;
2117
2118 if (str[0] == '0' && str[1])
2119 return -EINVAL;
2120 len = _parse_integer(str, 16, &eval);
2121 if (len & KSTRTOX_OVERFLOW)
2122 return -EINVAL;
2123 if (eval != (unsigned long)eval)
2124 return -EINVAL;
2125 str += len;
2126
2127 if (*str != '\0')
2128 return -EINVAL;
2129
2130 *start = sval;
2131 *end = eval;
2132
2133 return 0;
2134}
2135
2136static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
2137{
2138 unsigned long vm_start, vm_end;
2139 bool exact_vma_exists = false;
2140 struct mm_struct *mm = NULL;
2141 struct task_struct *task;
2142 struct inode *inode;
2143 int status = 0;
2144
2145 if (flags & LOOKUP_RCU)
2146 return -ECHILD;
2147
2148 inode = d_inode(dentry);
2149 task = get_proc_task(inode);
2150 if (!task)
2151 goto out_notask;
2152
2153 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
2154 if (IS_ERR_OR_NULL(mm))
2155 goto out;
2156
2157 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2158 status = mmap_read_lock_killable(mm);
2159 if (!status) {
2160 exact_vma_exists = !!find_exact_vma(mm, vm_start,
2161 vm_end);
2162 mmap_read_unlock(mm);
2163 }
2164 }
2165
2166 mmput(mm);
2167
2168 if (exact_vma_exists) {
2169 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
2170
2171 security_task_to_inode(task, inode);
2172 status = 1;
2173 }
2174
2175out:
2176 put_task_struct(task);
2177
2178out_notask:
2179 return status;
2180}
2181
2182static const struct dentry_operations tid_map_files_dentry_operations = {
2183 .d_revalidate = map_files_d_revalidate,
2184 .d_delete = pid_delete_dentry,
2185};
2186
2187static int map_files_get_link(struct dentry *dentry, struct path *path)
2188{
2189 unsigned long vm_start, vm_end;
2190 struct vm_area_struct *vma;
2191 struct task_struct *task;
2192 struct mm_struct *mm;
2193 int rc;
2194
2195 rc = -ENOENT;
2196 task = get_proc_task(d_inode(dentry));
2197 if (!task)
2198 goto out;
2199
2200 mm = get_task_mm(task);
2201 put_task_struct(task);
2202 if (!mm)
2203 goto out;
2204
2205 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2206 if (rc)
2207 goto out_mmput;
2208
2209 rc = mmap_read_lock_killable(mm);
2210 if (rc)
2211 goto out_mmput;
2212
2213 rc = -ENOENT;
2214 vma = find_exact_vma(mm, vm_start, vm_end);
2215 if (vma && vma->vm_file) {
2216 *path = *file_user_path(vma->vm_file);
2217 path_get(path);
2218 rc = 0;
2219 }
2220 mmap_read_unlock(mm);
2221
2222out_mmput:
2223 mmput(mm);
2224out:
2225 return rc;
2226}
2227
2228struct map_files_info {
2229 unsigned long start;
2230 unsigned long end;
2231 fmode_t mode;
2232};
2233
2234/*
2235 * Only allow CAP_SYS_ADMIN and CAP_CHECKPOINT_RESTORE to follow the links, due
2236 * to concerns about how the symlinks may be used to bypass permissions on
2237 * ancestor directories in the path to the file in question.
2238 */
2239static const char *
2240proc_map_files_get_link(struct dentry *dentry,
2241 struct inode *inode,
2242 struct delayed_call *done)
2243{
2244 if (!checkpoint_restore_ns_capable(&init_user_ns))
2245 return ERR_PTR(-EPERM);
2246
2247 return proc_pid_get_link(dentry, inode, done);
2248}
2249
2250/*
2251 * Identical to proc_pid_link_inode_operations except for get_link()
2252 */
2253static const struct inode_operations proc_map_files_link_inode_operations = {
2254 .readlink = proc_pid_readlink,
2255 .get_link = proc_map_files_get_link,
2256 .setattr = proc_setattr,
2257};
2258
2259static struct dentry *
2260proc_map_files_instantiate(struct dentry *dentry,
2261 struct task_struct *task, const void *ptr)
2262{
2263 fmode_t mode = (fmode_t)(unsigned long)ptr;
2264 struct proc_inode *ei;
2265 struct inode *inode;
2266
2267 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK |
2268 ((mode & FMODE_READ ) ? S_IRUSR : 0) |
2269 ((mode & FMODE_WRITE) ? S_IWUSR : 0));
2270 if (!inode)
2271 return ERR_PTR(-ENOENT);
2272
2273 ei = PROC_I(inode);
2274 ei->op.proc_get_link = map_files_get_link;
2275
2276 inode->i_op = &proc_map_files_link_inode_operations;
2277 inode->i_size = 64;
2278
2279 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2280 return d_splice_alias(inode, dentry);
2281}
2282
2283static struct dentry *proc_map_files_lookup(struct inode *dir,
2284 struct dentry *dentry, unsigned int flags)
2285{
2286 unsigned long vm_start, vm_end;
2287 struct vm_area_struct *vma;
2288 struct task_struct *task;
2289 struct dentry *result;
2290 struct mm_struct *mm;
2291
2292 result = ERR_PTR(-ENOENT);
2293 task = get_proc_task(dir);
2294 if (!task)
2295 goto out;
2296
2297 result = ERR_PTR(-EACCES);
2298 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2299 goto out_put_task;
2300
2301 result = ERR_PTR(-ENOENT);
2302 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2303 goto out_put_task;
2304
2305 mm = get_task_mm(task);
2306 if (!mm)
2307 goto out_put_task;
2308
2309 result = ERR_PTR(-EINTR);
2310 if (mmap_read_lock_killable(mm))
2311 goto out_put_mm;
2312
2313 result = ERR_PTR(-ENOENT);
2314 vma = find_exact_vma(mm, vm_start, vm_end);
2315 if (!vma)
2316 goto out_no_vma;
2317
2318 if (vma->vm_file)
2319 result = proc_map_files_instantiate(dentry, task,
2320 (void *)(unsigned long)vma->vm_file->f_mode);
2321
2322out_no_vma:
2323 mmap_read_unlock(mm);
2324out_put_mm:
2325 mmput(mm);
2326out_put_task:
2327 put_task_struct(task);
2328out:
2329 return result;
2330}
2331
2332static const struct inode_operations proc_map_files_inode_operations = {
2333 .lookup = proc_map_files_lookup,
2334 .permission = proc_fd_permission,
2335 .setattr = proc_setattr,
2336};
2337
2338static int
2339proc_map_files_readdir(struct file *file, struct dir_context *ctx)
2340{
2341 struct vm_area_struct *vma;
2342 struct task_struct *task;
2343 struct mm_struct *mm;
2344 unsigned long nr_files, pos, i;
2345 GENRADIX(struct map_files_info) fa;
2346 struct map_files_info *p;
2347 int ret;
2348 struct vma_iterator vmi;
2349
2350 genradix_init(&fa);
2351
2352 ret = -ENOENT;
2353 task = get_proc_task(file_inode(file));
2354 if (!task)
2355 goto out;
2356
2357 ret = -EACCES;
2358 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2359 goto out_put_task;
2360
2361 ret = 0;
2362 if (!dir_emit_dots(file, ctx))
2363 goto out_put_task;
2364
2365 mm = get_task_mm(task);
2366 if (!mm)
2367 goto out_put_task;
2368
2369 ret = mmap_read_lock_killable(mm);
2370 if (ret) {
2371 mmput(mm);
2372 goto out_put_task;
2373 }
2374
2375 nr_files = 0;
2376
2377 /*
2378 * We need two passes here:
2379 *
2380 * 1) Collect vmas of mapped files with mmap_lock taken
2381 * 2) Release mmap_lock and instantiate entries
2382 *
2383 * otherwise we get lockdep complained, since filldir()
2384 * routine might require mmap_lock taken in might_fault().
2385 */
2386
2387 pos = 2;
2388 vma_iter_init(&vmi, mm, 0);
2389 for_each_vma(vmi, vma) {
2390 if (!vma->vm_file)
2391 continue;
2392 if (++pos <= ctx->pos)
2393 continue;
2394
2395 p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL);
2396 if (!p) {
2397 ret = -ENOMEM;
2398 mmap_read_unlock(mm);
2399 mmput(mm);
2400 goto out_put_task;
2401 }
2402
2403 p->start = vma->vm_start;
2404 p->end = vma->vm_end;
2405 p->mode = vma->vm_file->f_mode;
2406 }
2407 mmap_read_unlock(mm);
2408 mmput(mm);
2409
2410 for (i = 0; i < nr_files; i++) {
2411 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */
2412 unsigned int len;
2413
2414 p = genradix_ptr(&fa, i);
2415 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);
2416 if (!proc_fill_cache(file, ctx,
2417 buf, len,
2418 proc_map_files_instantiate,
2419 task,
2420 (void *)(unsigned long)p->mode))
2421 break;
2422 ctx->pos++;
2423 }
2424
2425out_put_task:
2426 put_task_struct(task);
2427out:
2428 genradix_free(&fa);
2429 return ret;
2430}
2431
2432static const struct file_operations proc_map_files_operations = {
2433 .read = generic_read_dir,
2434 .iterate_shared = proc_map_files_readdir,
2435 .llseek = generic_file_llseek,
2436};
2437
2438#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
2439struct timers_private {
2440 struct pid *pid;
2441 struct task_struct *task;
2442 struct sighand_struct *sighand;
2443 struct pid_namespace *ns;
2444 unsigned long flags;
2445};
2446
2447static void *timers_start(struct seq_file *m, loff_t *pos)
2448{
2449 struct timers_private *tp = m->private;
2450
2451 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2452 if (!tp->task)
2453 return ERR_PTR(-ESRCH);
2454
2455 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2456 if (!tp->sighand)
2457 return ERR_PTR(-ESRCH);
2458
2459 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2460}
2461
2462static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2463{
2464 struct timers_private *tp = m->private;
2465 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2466}
2467
2468static void timers_stop(struct seq_file *m, void *v)
2469{
2470 struct timers_private *tp = m->private;
2471
2472 if (tp->sighand) {
2473 unlock_task_sighand(tp->task, &tp->flags);
2474 tp->sighand = NULL;
2475 }
2476
2477 if (tp->task) {
2478 put_task_struct(tp->task);
2479 tp->task = NULL;
2480 }
2481}
2482
2483static int show_timer(struct seq_file *m, void *v)
2484{
2485 struct k_itimer *timer;
2486 struct timers_private *tp = m->private;
2487 int notify;
2488 static const char * const nstr[] = {
2489 [SIGEV_SIGNAL] = "signal",
2490 [SIGEV_NONE] = "none",
2491 [SIGEV_THREAD] = "thread",
2492 };
2493
2494 timer = list_entry((struct list_head *)v, struct k_itimer, list);
2495 notify = timer->it_sigev_notify;
2496
2497 seq_printf(m, "ID: %d\n", timer->it_id);
2498 seq_printf(m, "signal: %d/%px\n",
2499 timer->sigq->info.si_signo,
2500 timer->sigq->info.si_value.sival_ptr);
2501 seq_printf(m, "notify: %s/%s.%d\n",
2502 nstr[notify & ~SIGEV_THREAD_ID],
2503 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2504 pid_nr_ns(timer->it_pid, tp->ns));
2505 seq_printf(m, "ClockID: %d\n", timer->it_clock);
2506
2507 return 0;
2508}
2509
2510static const struct seq_operations proc_timers_seq_ops = {
2511 .start = timers_start,
2512 .next = timers_next,
2513 .stop = timers_stop,
2514 .show = show_timer,
2515};
2516
2517static int proc_timers_open(struct inode *inode, struct file *file)
2518{
2519 struct timers_private *tp;
2520
2521 tp = __seq_open_private(file, &proc_timers_seq_ops,
2522 sizeof(struct timers_private));
2523 if (!tp)
2524 return -ENOMEM;
2525
2526 tp->pid = proc_pid(inode);
2527 tp->ns = proc_pid_ns(inode->i_sb);
2528 return 0;
2529}
2530
2531static const struct file_operations proc_timers_operations = {
2532 .open = proc_timers_open,
2533 .read = seq_read,
2534 .llseek = seq_lseek,
2535 .release = seq_release_private,
2536};
2537#endif
2538
2539static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2540 size_t count, loff_t *offset)
2541{
2542 struct inode *inode = file_inode(file);
2543 struct task_struct *p;
2544 u64 slack_ns;
2545 int err;
2546
2547 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2548 if (err < 0)
2549 return err;
2550
2551 p = get_proc_task(inode);
2552 if (!p)
2553 return -ESRCH;
2554
2555 if (p != current) {
2556 rcu_read_lock();
2557 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
2558 rcu_read_unlock();
2559 count = -EPERM;
2560 goto out;
2561 }
2562 rcu_read_unlock();
2563
2564 err = security_task_setscheduler(p);
2565 if (err) {
2566 count = err;
2567 goto out;
2568 }
2569 }
2570
2571 task_lock(p);
2572 if (slack_ns == 0)
2573 p->timer_slack_ns = p->default_timer_slack_ns;
2574 else
2575 p->timer_slack_ns = slack_ns;
2576 task_unlock(p);
2577
2578out:
2579 put_task_struct(p);
2580
2581 return count;
2582}
2583
2584static int timerslack_ns_show(struct seq_file *m, void *v)
2585{
2586 struct inode *inode = m->private;
2587 struct task_struct *p;
2588 int err = 0;
2589
2590 p = get_proc_task(inode);
2591 if (!p)
2592 return -ESRCH;
2593
2594 if (p != current) {
2595 rcu_read_lock();
2596 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
2597 rcu_read_unlock();
2598 err = -EPERM;
2599 goto out;
2600 }
2601 rcu_read_unlock();
2602
2603 err = security_task_getscheduler(p);
2604 if (err)
2605 goto out;
2606 }
2607
2608 task_lock(p);
2609 seq_printf(m, "%llu\n", p->timer_slack_ns);
2610 task_unlock(p);
2611
2612out:
2613 put_task_struct(p);
2614
2615 return err;
2616}
2617
2618static int timerslack_ns_open(struct inode *inode, struct file *filp)
2619{
2620 return single_open(filp, timerslack_ns_show, inode);
2621}
2622
2623static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2624 .open = timerslack_ns_open,
2625 .read = seq_read,
2626 .write = timerslack_ns_write,
2627 .llseek = seq_lseek,
2628 .release = single_release,
2629};
2630
2631static struct dentry *proc_pident_instantiate(struct dentry *dentry,
2632 struct task_struct *task, const void *ptr)
2633{
2634 const struct pid_entry *p = ptr;
2635 struct inode *inode;
2636 struct proc_inode *ei;
2637
2638 inode = proc_pid_make_inode(dentry->d_sb, task, p->mode);
2639 if (!inode)
2640 return ERR_PTR(-ENOENT);
2641
2642 ei = PROC_I(inode);
2643 if (S_ISDIR(inode->i_mode))
2644 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2645 if (p->iop)
2646 inode->i_op = p->iop;
2647 if (p->fop)
2648 inode->i_fop = p->fop;
2649 ei->op = p->op;
2650 pid_update_inode(task, inode);
2651 d_set_d_op(dentry, &pid_dentry_operations);
2652 return d_splice_alias(inode, dentry);
2653}
2654
2655static struct dentry *proc_pident_lookup(struct inode *dir,
2656 struct dentry *dentry,
2657 const struct pid_entry *p,
2658 const struct pid_entry *end)
2659{
2660 struct task_struct *task = get_proc_task(dir);
2661 struct dentry *res = ERR_PTR(-ENOENT);
2662
2663 if (!task)
2664 goto out_no_task;
2665
2666 /*
2667 * Yes, it does not scale. And it should not. Don't add
2668 * new entries into /proc/<tgid>/ without very good reasons.
2669 */
2670 for (; p < end; p++) {
2671 if (p->len != dentry->d_name.len)
2672 continue;
2673 if (!memcmp(dentry->d_name.name, p->name, p->len)) {
2674 res = proc_pident_instantiate(dentry, task, p);
2675 break;
2676 }
2677 }
2678 put_task_struct(task);
2679out_no_task:
2680 return res;
2681}
2682
2683static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
2684 const struct pid_entry *ents, unsigned int nents)
2685{
2686 struct task_struct *task = get_proc_task(file_inode(file));
2687 const struct pid_entry *p;
2688
2689 if (!task)
2690 return -ENOENT;
2691
2692 if (!dir_emit_dots(file, ctx))
2693 goto out;
2694
2695 if (ctx->pos >= nents + 2)
2696 goto out;
2697
2698 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
2699 if (!proc_fill_cache(file, ctx, p->name, p->len,
2700 proc_pident_instantiate, task, p))
2701 break;
2702 ctx->pos++;
2703 }
2704out:
2705 put_task_struct(task);
2706 return 0;
2707}
2708
2709#ifdef CONFIG_SECURITY
2710static int proc_pid_attr_open(struct inode *inode, struct file *file)
2711{
2712 file->private_data = NULL;
2713 __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
2714 return 0;
2715}
2716
2717static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2718 size_t count, loff_t *ppos)
2719{
2720 struct inode * inode = file_inode(file);
2721 char *p = NULL;
2722 ssize_t length;
2723 struct task_struct *task = get_proc_task(inode);
2724
2725 if (!task)
2726 return -ESRCH;
2727
2728 length = security_getprocattr(task, PROC_I(inode)->op.lsmid,
2729 file->f_path.dentry->d_name.name,
2730 &p);
2731 put_task_struct(task);
2732 if (length > 0)
2733 length = simple_read_from_buffer(buf, count, ppos, p, length);
2734 kfree(p);
2735 return length;
2736}
2737
2738static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2739 size_t count, loff_t *ppos)
2740{
2741 struct inode * inode = file_inode(file);
2742 struct task_struct *task;
2743 void *page;
2744 int rv;
2745
2746 /* A task may only write when it was the opener. */
2747 if (file->private_data != current->mm)
2748 return -EPERM;
2749
2750 rcu_read_lock();
2751 task = pid_task(proc_pid(inode), PIDTYPE_PID);
2752 if (!task) {
2753 rcu_read_unlock();
2754 return -ESRCH;
2755 }
2756 /* A task may only write its own attributes. */
2757 if (current != task) {
2758 rcu_read_unlock();
2759 return -EACCES;
2760 }
2761 /* Prevent changes to overridden credentials. */
2762 if (current_cred() != current_real_cred()) {
2763 rcu_read_unlock();
2764 return -EBUSY;
2765 }
2766 rcu_read_unlock();
2767
2768 if (count > PAGE_SIZE)
2769 count = PAGE_SIZE;
2770
2771 /* No partial writes. */
2772 if (*ppos != 0)
2773 return -EINVAL;
2774
2775 page = memdup_user(buf, count);
2776 if (IS_ERR(page)) {
2777 rv = PTR_ERR(page);
2778 goto out;
2779 }
2780
2781 /* Guard against adverse ptrace interaction */
2782 rv = mutex_lock_interruptible(¤t->signal->cred_guard_mutex);
2783 if (rv < 0)
2784 goto out_free;
2785
2786 rv = security_setprocattr(PROC_I(inode)->op.lsmid,
2787 file->f_path.dentry->d_name.name, page,
2788 count);
2789 mutex_unlock(¤t->signal->cred_guard_mutex);
2790out_free:
2791 kfree(page);
2792out:
2793 return rv;
2794}
2795
2796static const struct file_operations proc_pid_attr_operations = {
2797 .open = proc_pid_attr_open,
2798 .read = proc_pid_attr_read,
2799 .write = proc_pid_attr_write,
2800 .llseek = generic_file_llseek,
2801 .release = mem_release,
2802};
2803
2804#define LSM_DIR_OPS(LSM) \
2805static int proc_##LSM##_attr_dir_iterate(struct file *filp, \
2806 struct dir_context *ctx) \
2807{ \
2808 return proc_pident_readdir(filp, ctx, \
2809 LSM##_attr_dir_stuff, \
2810 ARRAY_SIZE(LSM##_attr_dir_stuff)); \
2811} \
2812\
2813static const struct file_operations proc_##LSM##_attr_dir_ops = { \
2814 .read = generic_read_dir, \
2815 .iterate_shared = proc_##LSM##_attr_dir_iterate, \
2816 .llseek = default_llseek, \
2817}; \
2818\
2819static struct dentry *proc_##LSM##_attr_dir_lookup(struct inode *dir, \
2820 struct dentry *dentry, unsigned int flags) \
2821{ \
2822 return proc_pident_lookup(dir, dentry, \
2823 LSM##_attr_dir_stuff, \
2824 LSM##_attr_dir_stuff + ARRAY_SIZE(LSM##_attr_dir_stuff)); \
2825} \
2826\
2827static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \
2828 .lookup = proc_##LSM##_attr_dir_lookup, \
2829 .getattr = pid_getattr, \
2830 .setattr = proc_setattr, \
2831}
2832
2833#ifdef CONFIG_SECURITY_SMACK
2834static const struct pid_entry smack_attr_dir_stuff[] = {
2835 ATTR(LSM_ID_SMACK, "current", 0666),
2836};
2837LSM_DIR_OPS(smack);
2838#endif
2839
2840#ifdef CONFIG_SECURITY_APPARMOR
2841static const struct pid_entry apparmor_attr_dir_stuff[] = {
2842 ATTR(LSM_ID_APPARMOR, "current", 0666),
2843 ATTR(LSM_ID_APPARMOR, "prev", 0444),
2844 ATTR(LSM_ID_APPARMOR, "exec", 0666),
2845};
2846LSM_DIR_OPS(apparmor);
2847#endif
2848
2849static const struct pid_entry attr_dir_stuff[] = {
2850 ATTR(LSM_ID_UNDEF, "current", 0666),
2851 ATTR(LSM_ID_UNDEF, "prev", 0444),
2852 ATTR(LSM_ID_UNDEF, "exec", 0666),
2853 ATTR(LSM_ID_UNDEF, "fscreate", 0666),
2854 ATTR(LSM_ID_UNDEF, "keycreate", 0666),
2855 ATTR(LSM_ID_UNDEF, "sockcreate", 0666),
2856#ifdef CONFIG_SECURITY_SMACK
2857 DIR("smack", 0555,
2858 proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
2859#endif
2860#ifdef CONFIG_SECURITY_APPARMOR
2861 DIR("apparmor", 0555,
2862 proc_apparmor_attr_dir_inode_ops, proc_apparmor_attr_dir_ops),
2863#endif
2864};
2865
2866static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
2867{
2868 return proc_pident_readdir(file, ctx,
2869 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2870}
2871
2872static const struct file_operations proc_attr_dir_operations = {
2873 .read = generic_read_dir,
2874 .iterate_shared = proc_attr_dir_readdir,
2875 .llseek = generic_file_llseek,
2876};
2877
2878static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2879 struct dentry *dentry, unsigned int flags)
2880{
2881 return proc_pident_lookup(dir, dentry,
2882 attr_dir_stuff,
2883 attr_dir_stuff + ARRAY_SIZE(attr_dir_stuff));
2884}
2885
2886static const struct inode_operations proc_attr_dir_inode_operations = {
2887 .lookup = proc_attr_dir_lookup,
2888 .getattr = pid_getattr,
2889 .setattr = proc_setattr,
2890};
2891
2892#endif
2893
2894#ifdef CONFIG_ELF_CORE
2895static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2896 size_t count, loff_t *ppos)
2897{
2898 struct task_struct *task = get_proc_task(file_inode(file));
2899 struct mm_struct *mm;
2900 char buffer[PROC_NUMBUF];
2901 size_t len;
2902 int ret;
2903
2904 if (!task)
2905 return -ESRCH;
2906
2907 ret = 0;
2908 mm = get_task_mm(task);
2909 if (mm) {
2910 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2911 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2912 MMF_DUMP_FILTER_SHIFT));
2913 mmput(mm);
2914 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2915 }
2916
2917 put_task_struct(task);
2918
2919 return ret;
2920}
2921
2922static ssize_t proc_coredump_filter_write(struct file *file,
2923 const char __user *buf,
2924 size_t count,
2925 loff_t *ppos)
2926{
2927 struct task_struct *task;
2928 struct mm_struct *mm;
2929 unsigned int val;
2930 int ret;
2931 int i;
2932 unsigned long mask;
2933
2934 ret = kstrtouint_from_user(buf, count, 0, &val);
2935 if (ret < 0)
2936 return ret;
2937
2938 ret = -ESRCH;
2939 task = get_proc_task(file_inode(file));
2940 if (!task)
2941 goto out_no_task;
2942
2943 mm = get_task_mm(task);
2944 if (!mm)
2945 goto out_no_mm;
2946 ret = 0;
2947
2948 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2949 if (val & mask)
2950 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2951 else
2952 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2953 }
2954
2955 mmput(mm);
2956 out_no_mm:
2957 put_task_struct(task);
2958 out_no_task:
2959 if (ret < 0)
2960 return ret;
2961 return count;
2962}
2963
2964static const struct file_operations proc_coredump_filter_operations = {
2965 .read = proc_coredump_filter_read,
2966 .write = proc_coredump_filter_write,
2967 .llseek = generic_file_llseek,
2968};
2969#endif
2970
2971#ifdef CONFIG_TASK_IO_ACCOUNTING
2972static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
2973{
2974 struct task_io_accounting acct;
2975 int result;
2976
2977 result = down_read_killable(&task->signal->exec_update_lock);
2978 if (result)
2979 return result;
2980
2981 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
2982 result = -EACCES;
2983 goto out_unlock;
2984 }
2985
2986 if (whole) {
2987 struct signal_struct *sig = task->signal;
2988 struct task_struct *t;
2989 unsigned int seq = 1;
2990 unsigned long flags;
2991
2992 rcu_read_lock();
2993 do {
2994 seq++; /* 2 on the 1st/lockless path, otherwise odd */
2995 flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq);
2996
2997 acct = sig->ioac;
2998 __for_each_thread(sig, t)
2999 task_io_accounting_add(&acct, &t->ioac);
3000
3001 } while (need_seqretry(&sig->stats_lock, seq));
3002 done_seqretry_irqrestore(&sig->stats_lock, seq, flags);
3003 rcu_read_unlock();
3004 } else {
3005 acct = task->ioac;
3006 }
3007
3008 seq_printf(m,
3009 "rchar: %llu\n"
3010 "wchar: %llu\n"
3011 "syscr: %llu\n"
3012 "syscw: %llu\n"
3013 "read_bytes: %llu\n"
3014 "write_bytes: %llu\n"
3015 "cancelled_write_bytes: %llu\n",
3016 (unsigned long long)acct.rchar,
3017 (unsigned long long)acct.wchar,
3018 (unsigned long long)acct.syscr,
3019 (unsigned long long)acct.syscw,
3020 (unsigned long long)acct.read_bytes,
3021 (unsigned long long)acct.write_bytes,
3022 (unsigned long long)acct.cancelled_write_bytes);
3023 result = 0;
3024
3025out_unlock:
3026 up_read(&task->signal->exec_update_lock);
3027 return result;
3028}
3029
3030static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
3031 struct pid *pid, struct task_struct *task)
3032{
3033 return do_io_accounting(task, m, 0);
3034}
3035
3036static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
3037 struct pid *pid, struct task_struct *task)
3038{
3039 return do_io_accounting(task, m, 1);
3040}
3041#endif /* CONFIG_TASK_IO_ACCOUNTING */
3042
3043#ifdef CONFIG_USER_NS
3044static int proc_id_map_open(struct inode *inode, struct file *file,
3045 const struct seq_operations *seq_ops)
3046{
3047 struct user_namespace *ns = NULL;
3048 struct task_struct *task;
3049 struct seq_file *seq;
3050 int ret = -EINVAL;
3051
3052 task = get_proc_task(inode);
3053 if (task) {
3054 rcu_read_lock();
3055 ns = get_user_ns(task_cred_xxx(task, user_ns));
3056 rcu_read_unlock();
3057 put_task_struct(task);
3058 }
3059 if (!ns)
3060 goto err;
3061
3062 ret = seq_open(file, seq_ops);
3063 if (ret)
3064 goto err_put_ns;
3065
3066 seq = file->private_data;
3067 seq->private = ns;
3068
3069 return 0;
3070err_put_ns:
3071 put_user_ns(ns);
3072err:
3073 return ret;
3074}
3075
3076static int proc_id_map_release(struct inode *inode, struct file *file)
3077{
3078 struct seq_file *seq = file->private_data;
3079 struct user_namespace *ns = seq->private;
3080 put_user_ns(ns);
3081 return seq_release(inode, file);
3082}
3083
3084static int proc_uid_map_open(struct inode *inode, struct file *file)
3085{
3086 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
3087}
3088
3089static int proc_gid_map_open(struct inode *inode, struct file *file)
3090{
3091 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
3092}
3093
3094static int proc_projid_map_open(struct inode *inode, struct file *file)
3095{
3096 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
3097}
3098
3099static const struct file_operations proc_uid_map_operations = {
3100 .open = proc_uid_map_open,
3101 .write = proc_uid_map_write,
3102 .read = seq_read,
3103 .llseek = seq_lseek,
3104 .release = proc_id_map_release,
3105};
3106
3107static const struct file_operations proc_gid_map_operations = {
3108 .open = proc_gid_map_open,
3109 .write = proc_gid_map_write,
3110 .read = seq_read,
3111 .llseek = seq_lseek,
3112 .release = proc_id_map_release,
3113};
3114
3115static const struct file_operations proc_projid_map_operations = {
3116 .open = proc_projid_map_open,
3117 .write = proc_projid_map_write,
3118 .read = seq_read,
3119 .llseek = seq_lseek,
3120 .release = proc_id_map_release,
3121};
3122
3123static int proc_setgroups_open(struct inode *inode, struct file *file)
3124{
3125 struct user_namespace *ns = NULL;
3126 struct task_struct *task;
3127 int ret;
3128
3129 ret = -ESRCH;
3130 task = get_proc_task(inode);
3131 if (task) {
3132 rcu_read_lock();
3133 ns = get_user_ns(task_cred_xxx(task, user_ns));
3134 rcu_read_unlock();
3135 put_task_struct(task);
3136 }
3137 if (!ns)
3138 goto err;
3139
3140 if (file->f_mode & FMODE_WRITE) {
3141 ret = -EACCES;
3142 if (!ns_capable(ns, CAP_SYS_ADMIN))
3143 goto err_put_ns;
3144 }
3145
3146 ret = single_open(file, &proc_setgroups_show, ns);
3147 if (ret)
3148 goto err_put_ns;
3149
3150 return 0;
3151err_put_ns:
3152 put_user_ns(ns);
3153err:
3154 return ret;
3155}
3156
3157static int proc_setgroups_release(struct inode *inode, struct file *file)
3158{
3159 struct seq_file *seq = file->private_data;
3160 struct user_namespace *ns = seq->private;
3161 int ret = single_release(inode, file);
3162 put_user_ns(ns);
3163 return ret;
3164}
3165
3166static const struct file_operations proc_setgroups_operations = {
3167 .open = proc_setgroups_open,
3168 .write = proc_setgroups_write,
3169 .read = seq_read,
3170 .llseek = seq_lseek,
3171 .release = proc_setgroups_release,
3172};
3173#endif /* CONFIG_USER_NS */
3174
3175static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
3176 struct pid *pid, struct task_struct *task)
3177{
3178 int err = lock_trace(task);
3179 if (!err) {
3180 seq_printf(m, "%08x\n", task->personality);
3181 unlock_trace(task);
3182 }
3183 return err;
3184}
3185
3186#ifdef CONFIG_LIVEPATCH
3187static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns,
3188 struct pid *pid, struct task_struct *task)
3189{
3190 seq_printf(m, "%d\n", task->patch_state);
3191 return 0;
3192}
3193#endif /* CONFIG_LIVEPATCH */
3194
3195#ifdef CONFIG_KSM
3196static int proc_pid_ksm_merging_pages(struct seq_file *m, struct pid_namespace *ns,
3197 struct pid *pid, struct task_struct *task)
3198{
3199 struct mm_struct *mm;
3200
3201 mm = get_task_mm(task);
3202 if (mm) {
3203 seq_printf(m, "%lu\n", mm->ksm_merging_pages);
3204 mmput(mm);
3205 }
3206
3207 return 0;
3208}
3209static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns,
3210 struct pid *pid, struct task_struct *task)
3211{
3212 struct mm_struct *mm;
3213
3214 mm = get_task_mm(task);
3215 if (mm) {
3216 seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items);
3217 seq_printf(m, "ksm_zero_pages %lu\n", mm->ksm_zero_pages);
3218 seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages);
3219 seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm));
3220 mmput(mm);
3221 }
3222
3223 return 0;
3224}
3225#endif /* CONFIG_KSM */
3226
3227#ifdef CONFIG_STACKLEAK_METRICS
3228static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns,
3229 struct pid *pid, struct task_struct *task)
3230{
3231 unsigned long prev_depth = THREAD_SIZE -
3232 (task->prev_lowest_stack & (THREAD_SIZE - 1));
3233 unsigned long depth = THREAD_SIZE -
3234 (task->lowest_stack & (THREAD_SIZE - 1));
3235
3236 seq_printf(m, "previous stack depth: %lu\nstack depth: %lu\n",
3237 prev_depth, depth);
3238 return 0;
3239}
3240#endif /* CONFIG_STACKLEAK_METRICS */
3241
3242/*
3243 * Thread groups
3244 */
3245static const struct file_operations proc_task_operations;
3246static const struct inode_operations proc_task_inode_operations;
3247
3248static const struct pid_entry tgid_base_stuff[] = {
3249 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
3250 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3251 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
3252 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3253 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3254#ifdef CONFIG_NET
3255 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3256#endif
3257 REG("environ", S_IRUSR, proc_environ_operations),
3258 REG("auxv", S_IRUSR, proc_auxv_operations),
3259 ONE("status", S_IRUGO, proc_pid_status),
3260 ONE("personality", S_IRUSR, proc_pid_personality),
3261 ONE("limits", S_IRUGO, proc_pid_limits),
3262#ifdef CONFIG_SCHED_DEBUG
3263 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3264#endif
3265#ifdef CONFIG_SCHED_AUTOGROUP
3266 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
3267#endif
3268#ifdef CONFIG_TIME_NS
3269 REG("timens_offsets", S_IRUGO|S_IWUSR, proc_timens_offsets_operations),
3270#endif
3271 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3272#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3273 ONE("syscall", S_IRUSR, proc_pid_syscall),
3274#endif
3275 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3276 ONE("stat", S_IRUGO, proc_tgid_stat),
3277 ONE("statm", S_IRUGO, proc_pid_statm),
3278 REG("maps", S_IRUGO, proc_pid_maps_operations),
3279#ifdef CONFIG_NUMA
3280 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
3281#endif
3282 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3283 LNK("cwd", proc_cwd_link),
3284 LNK("root", proc_root_link),
3285 LNK("exe", proc_exe_link),
3286 REG("mounts", S_IRUGO, proc_mounts_operations),
3287 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3288 REG("mountstats", S_IRUSR, proc_mountstats_operations),
3289#ifdef CONFIG_PROC_PAGE_MONITOR
3290 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3291 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
3292 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3293 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3294#endif
3295#ifdef CONFIG_SECURITY
3296 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3297#endif
3298#ifdef CONFIG_KALLSYMS
3299 ONE("wchan", S_IRUGO, proc_pid_wchan),
3300#endif
3301#ifdef CONFIG_STACKTRACE
3302 ONE("stack", S_IRUSR, proc_pid_stack),
3303#endif
3304#ifdef CONFIG_SCHED_INFO
3305 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3306#endif
3307#ifdef CONFIG_LATENCYTOP
3308 REG("latency", S_IRUGO, proc_lstats_operations),
3309#endif
3310#ifdef CONFIG_PROC_PID_CPUSET
3311 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3312#endif
3313#ifdef CONFIG_CGROUPS
3314 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3315#endif
3316#ifdef CONFIG_PROC_CPU_RESCTRL
3317 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),
3318#endif
3319 ONE("oom_score", S_IRUGO, proc_oom_score),
3320 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3321 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3322#ifdef CONFIG_AUDIT
3323 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3324 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3325#endif
3326#ifdef CONFIG_FAULT_INJECTION
3327 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3328 REG("fail-nth", 0644, proc_fail_nth_operations),
3329#endif
3330#ifdef CONFIG_ELF_CORE
3331 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3332#endif
3333#ifdef CONFIG_TASK_IO_ACCOUNTING
3334 ONE("io", S_IRUSR, proc_tgid_io_accounting),
3335#endif
3336#ifdef CONFIG_USER_NS
3337 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3338 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3339 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3340 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3341#endif
3342#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
3343 REG("timers", S_IRUGO, proc_timers_operations),
3344#endif
3345 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
3346#ifdef CONFIG_LIVEPATCH
3347 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3348#endif
3349#ifdef CONFIG_STACKLEAK_METRICS
3350 ONE("stack_depth", S_IRUGO, proc_stack_depth),
3351#endif
3352#ifdef CONFIG_PROC_PID_ARCH_STATUS
3353 ONE("arch_status", S_IRUGO, proc_pid_arch_status),
3354#endif
3355#ifdef CONFIG_SECCOMP_CACHE_DEBUG
3356 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),
3357#endif
3358#ifdef CONFIG_KSM
3359 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages),
3360 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat),
3361#endif
3362};
3363
3364static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
3365{
3366 return proc_pident_readdir(file, ctx,
3367 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3368}
3369
3370static const struct file_operations proc_tgid_base_operations = {
3371 .read = generic_read_dir,
3372 .iterate_shared = proc_tgid_base_readdir,
3373 .llseek = generic_file_llseek,
3374};
3375
3376struct pid *tgid_pidfd_to_pid(const struct file *file)
3377{
3378 if (file->f_op != &proc_tgid_base_operations)
3379 return ERR_PTR(-EBADF);
3380
3381 return proc_pid(file_inode(file));
3382}
3383
3384static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3385{
3386 return proc_pident_lookup(dir, dentry,
3387 tgid_base_stuff,
3388 tgid_base_stuff + ARRAY_SIZE(tgid_base_stuff));
3389}
3390
3391static const struct inode_operations proc_tgid_base_inode_operations = {
3392 .lookup = proc_tgid_base_lookup,
3393 .getattr = pid_getattr,
3394 .setattr = proc_setattr,
3395 .permission = proc_pid_permission,
3396};
3397
3398/**
3399 * proc_flush_pid - Remove dcache entries for @pid from the /proc dcache.
3400 * @pid: pid that should be flushed.
3401 *
3402 * This function walks a list of inodes (that belong to any proc
3403 * filesystem) that are attached to the pid and flushes them from
3404 * the dentry cache.
3405 *
3406 * It is safe and reasonable to cache /proc entries for a task until
3407 * that task exits. After that they just clog up the dcache with
3408 * useless entries, possibly causing useful dcache entries to be
3409 * flushed instead. This routine is provided to flush those useless
3410 * dcache entries when a process is reaped.
3411 *
3412 * NOTE: This routine is just an optimization so it does not guarantee
3413 * that no dcache entries will exist after a process is reaped
3414 * it just makes it very unlikely that any will persist.
3415 */
3416
3417void proc_flush_pid(struct pid *pid)
3418{
3419 proc_invalidate_siblings_dcache(&pid->inodes, &pid->lock);
3420}
3421
3422static struct dentry *proc_pid_instantiate(struct dentry * dentry,
3423 struct task_struct *task, const void *ptr)
3424{
3425 struct inode *inode;
3426
3427 inode = proc_pid_make_base_inode(dentry->d_sb, task,
3428 S_IFDIR | S_IRUGO | S_IXUGO);
3429 if (!inode)
3430 return ERR_PTR(-ENOENT);
3431
3432 inode->i_op = &proc_tgid_base_inode_operations;
3433 inode->i_fop = &proc_tgid_base_operations;
3434 inode->i_flags|=S_IMMUTABLE;
3435
3436 set_nlink(inode, nlink_tgid);
3437 pid_update_inode(task, inode);
3438
3439 d_set_d_op(dentry, &pid_dentry_operations);
3440 return d_splice_alias(inode, dentry);
3441}
3442
3443struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags)
3444{
3445 struct task_struct *task;
3446 unsigned tgid;
3447 struct proc_fs_info *fs_info;
3448 struct pid_namespace *ns;
3449 struct dentry *result = ERR_PTR(-ENOENT);
3450
3451 tgid = name_to_int(&dentry->d_name);
3452 if (tgid == ~0U)
3453 goto out;
3454
3455 fs_info = proc_sb_info(dentry->d_sb);
3456 ns = fs_info->pid_ns;
3457 rcu_read_lock();
3458 task = find_task_by_pid_ns(tgid, ns);
3459 if (task)
3460 get_task_struct(task);
3461 rcu_read_unlock();
3462 if (!task)
3463 goto out;
3464
3465 /* Limit procfs to only ptraceable tasks */
3466 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) {
3467 if (!has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS))
3468 goto out_put_task;
3469 }
3470
3471 result = proc_pid_instantiate(dentry, task, NULL);
3472out_put_task:
3473 put_task_struct(task);
3474out:
3475 return result;
3476}
3477
3478/*
3479 * Find the first task with tgid >= tgid
3480 *
3481 */
3482struct tgid_iter {
3483 unsigned int tgid;
3484 struct task_struct *task;
3485};
3486static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3487{
3488 struct pid *pid;
3489
3490 if (iter.task)
3491 put_task_struct(iter.task);
3492 rcu_read_lock();
3493retry:
3494 iter.task = NULL;
3495 pid = find_ge_pid(iter.tgid, ns);
3496 if (pid) {
3497 iter.tgid = pid_nr_ns(pid, ns);
3498 iter.task = pid_task(pid, PIDTYPE_TGID);
3499 if (!iter.task) {
3500 iter.tgid += 1;
3501 goto retry;
3502 }
3503 get_task_struct(iter.task);
3504 }
3505 rcu_read_unlock();
3506 return iter;
3507}
3508
3509#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
3510
3511/* for the /proc/ directory itself, after non-process stuff has been done */
3512int proc_pid_readdir(struct file *file, struct dir_context *ctx)
3513{
3514 struct tgid_iter iter;
3515 struct proc_fs_info *fs_info = proc_sb_info(file_inode(file)->i_sb);
3516 struct pid_namespace *ns = proc_pid_ns(file_inode(file)->i_sb);
3517 loff_t pos = ctx->pos;
3518
3519 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
3520 return 0;
3521
3522 if (pos == TGID_OFFSET - 2) {
3523 struct inode *inode = d_inode(fs_info->proc_self);
3524 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
3525 return 0;
3526 ctx->pos = pos = pos + 1;
3527 }
3528 if (pos == TGID_OFFSET - 1) {
3529 struct inode *inode = d_inode(fs_info->proc_thread_self);
3530 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3531 return 0;
3532 ctx->pos = pos = pos + 1;
3533 }
3534 iter.tgid = pos - TGID_OFFSET;
3535 iter.task = NULL;
3536 for (iter = next_tgid(ns, iter);
3537 iter.task;
3538 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3539 char name[10 + 1];
3540 unsigned int len;
3541
3542 cond_resched();
3543 if (!has_pid_permissions(fs_info, iter.task, HIDEPID_INVISIBLE))
3544 continue;
3545
3546 len = snprintf(name, sizeof(name), "%u", iter.tgid);
3547 ctx->pos = iter.tgid + TGID_OFFSET;
3548 if (!proc_fill_cache(file, ctx, name, len,
3549 proc_pid_instantiate, iter.task, NULL)) {
3550 put_task_struct(iter.task);
3551 return 0;
3552 }
3553 }
3554 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
3555 return 0;
3556}
3557
3558/*
3559 * proc_tid_comm_permission is a special permission function exclusively
3560 * used for the node /proc/<pid>/task/<tid>/comm.
3561 * It bypasses generic permission checks in the case where a task of the same
3562 * task group attempts to access the node.
3563 * The rationale behind this is that glibc and bionic access this node for
3564 * cross thread naming (pthread_set/getname_np(!self)). However, if
3565 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3566 * which locks out the cross thread naming implementation.
3567 * This function makes sure that the node is always accessible for members of
3568 * same thread group.
3569 */
3570static int proc_tid_comm_permission(struct mnt_idmap *idmap,
3571 struct inode *inode, int mask)
3572{
3573 bool is_same_tgroup;
3574 struct task_struct *task;
3575
3576 task = get_proc_task(inode);
3577 if (!task)
3578 return -ESRCH;
3579 is_same_tgroup = same_thread_group(current, task);
3580 put_task_struct(task);
3581
3582 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3583 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3584 * read or written by the members of the corresponding
3585 * thread group.
3586 */
3587 return 0;
3588 }
3589
3590 return generic_permission(&nop_mnt_idmap, inode, mask);
3591}
3592
3593static const struct inode_operations proc_tid_comm_inode_operations = {
3594 .setattr = proc_setattr,
3595 .permission = proc_tid_comm_permission,
3596};
3597
3598/*
3599 * Tasks
3600 */
3601static const struct pid_entry tid_base_stuff[] = {
3602 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3603 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3604 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3605#ifdef CONFIG_NET
3606 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3607#endif
3608 REG("environ", S_IRUSR, proc_environ_operations),
3609 REG("auxv", S_IRUSR, proc_auxv_operations),
3610 ONE("status", S_IRUGO, proc_pid_status),
3611 ONE("personality", S_IRUSR, proc_pid_personality),
3612 ONE("limits", S_IRUGO, proc_pid_limits),
3613#ifdef CONFIG_SCHED_DEBUG
3614 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3615#endif
3616 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3617 &proc_tid_comm_inode_operations,
3618 &proc_pid_set_comm_operations, {}),
3619#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3620 ONE("syscall", S_IRUSR, proc_pid_syscall),
3621#endif
3622 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3623 ONE("stat", S_IRUGO, proc_tid_stat),
3624 ONE("statm", S_IRUGO, proc_pid_statm),
3625 REG("maps", S_IRUGO, proc_pid_maps_operations),
3626#ifdef CONFIG_PROC_CHILDREN
3627 REG("children", S_IRUGO, proc_tid_children_operations),
3628#endif
3629#ifdef CONFIG_NUMA
3630 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
3631#endif
3632 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3633 LNK("cwd", proc_cwd_link),
3634 LNK("root", proc_root_link),
3635 LNK("exe", proc_exe_link),
3636 REG("mounts", S_IRUGO, proc_mounts_operations),
3637 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3638#ifdef CONFIG_PROC_PAGE_MONITOR
3639 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3640 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
3641 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3642 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3643#endif
3644#ifdef CONFIG_SECURITY
3645 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3646#endif
3647#ifdef CONFIG_KALLSYMS
3648 ONE("wchan", S_IRUGO, proc_pid_wchan),
3649#endif
3650#ifdef CONFIG_STACKTRACE
3651 ONE("stack", S_IRUSR, proc_pid_stack),
3652#endif
3653#ifdef CONFIG_SCHED_INFO
3654 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3655#endif
3656#ifdef CONFIG_LATENCYTOP
3657 REG("latency", S_IRUGO, proc_lstats_operations),
3658#endif
3659#ifdef CONFIG_PROC_PID_CPUSET
3660 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3661#endif
3662#ifdef CONFIG_CGROUPS
3663 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3664#endif
3665#ifdef CONFIG_PROC_CPU_RESCTRL
3666 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),
3667#endif
3668 ONE("oom_score", S_IRUGO, proc_oom_score),
3669 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3670 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3671#ifdef CONFIG_AUDIT
3672 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3673 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3674#endif
3675#ifdef CONFIG_FAULT_INJECTION
3676 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3677 REG("fail-nth", 0644, proc_fail_nth_operations),
3678#endif
3679#ifdef CONFIG_TASK_IO_ACCOUNTING
3680 ONE("io", S_IRUSR, proc_tid_io_accounting),
3681#endif
3682#ifdef CONFIG_USER_NS
3683 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3684 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3685 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3686 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3687#endif
3688#ifdef CONFIG_LIVEPATCH
3689 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3690#endif
3691#ifdef CONFIG_PROC_PID_ARCH_STATUS
3692 ONE("arch_status", S_IRUGO, proc_pid_arch_status),
3693#endif
3694#ifdef CONFIG_SECCOMP_CACHE_DEBUG
3695 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),
3696#endif
3697#ifdef CONFIG_KSM
3698 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages),
3699 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat),
3700#endif
3701};
3702
3703static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
3704{
3705 return proc_pident_readdir(file, ctx,
3706 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3707}
3708
3709static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3710{
3711 return proc_pident_lookup(dir, dentry,
3712 tid_base_stuff,
3713 tid_base_stuff + ARRAY_SIZE(tid_base_stuff));
3714}
3715
3716static const struct file_operations proc_tid_base_operations = {
3717 .read = generic_read_dir,
3718 .iterate_shared = proc_tid_base_readdir,
3719 .llseek = generic_file_llseek,
3720};
3721
3722static const struct inode_operations proc_tid_base_inode_operations = {
3723 .lookup = proc_tid_base_lookup,
3724 .getattr = pid_getattr,
3725 .setattr = proc_setattr,
3726};
3727
3728static struct dentry *proc_task_instantiate(struct dentry *dentry,
3729 struct task_struct *task, const void *ptr)
3730{
3731 struct inode *inode;
3732 inode = proc_pid_make_base_inode(dentry->d_sb, task,
3733 S_IFDIR | S_IRUGO | S_IXUGO);
3734 if (!inode)
3735 return ERR_PTR(-ENOENT);
3736
3737 inode->i_op = &proc_tid_base_inode_operations;
3738 inode->i_fop = &proc_tid_base_operations;
3739 inode->i_flags |= S_IMMUTABLE;
3740
3741 set_nlink(inode, nlink_tid);
3742 pid_update_inode(task, inode);
3743
3744 d_set_d_op(dentry, &pid_dentry_operations);
3745 return d_splice_alias(inode, dentry);
3746}
3747
3748static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3749{
3750 struct task_struct *task;
3751 struct task_struct *leader = get_proc_task(dir);
3752 unsigned tid;
3753 struct proc_fs_info *fs_info;
3754 struct pid_namespace *ns;
3755 struct dentry *result = ERR_PTR(-ENOENT);
3756
3757 if (!leader)
3758 goto out_no_task;
3759
3760 tid = name_to_int(&dentry->d_name);
3761 if (tid == ~0U)
3762 goto out;
3763
3764 fs_info = proc_sb_info(dentry->d_sb);
3765 ns = fs_info->pid_ns;
3766 rcu_read_lock();
3767 task = find_task_by_pid_ns(tid, ns);
3768 if (task)
3769 get_task_struct(task);
3770 rcu_read_unlock();
3771 if (!task)
3772 goto out;
3773 if (!same_thread_group(leader, task))
3774 goto out_drop_task;
3775
3776 result = proc_task_instantiate(dentry, task, NULL);
3777out_drop_task:
3778 put_task_struct(task);
3779out:
3780 put_task_struct(leader);
3781out_no_task:
3782 return result;
3783}
3784
3785/*
3786 * Find the first tid of a thread group to return to user space.
3787 *
3788 * Usually this is just the thread group leader, but if the users
3789 * buffer was too small or there was a seek into the middle of the
3790 * directory we have more work todo.
3791 *
3792 * In the case of a short read we start with find_task_by_pid.
3793 *
3794 * In the case of a seek we start with the leader and walk nr
3795 * threads past it.
3796 */
3797static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3798 struct pid_namespace *ns)
3799{
3800 struct task_struct *pos, *task;
3801 unsigned long nr = f_pos;
3802
3803 if (nr != f_pos) /* 32bit overflow? */
3804 return NULL;
3805
3806 rcu_read_lock();
3807 task = pid_task(pid, PIDTYPE_PID);
3808 if (!task)
3809 goto fail;
3810
3811 /* Attempt to start with the tid of a thread */
3812 if (tid && nr) {
3813 pos = find_task_by_pid_ns(tid, ns);
3814 if (pos && same_thread_group(pos, task))
3815 goto found;
3816 }
3817
3818 /* If nr exceeds the number of threads there is nothing todo */
3819 if (nr >= get_nr_threads(task))
3820 goto fail;
3821
3822 /* If we haven't found our starting place yet start
3823 * with the leader and walk nr threads forward.
3824 */
3825 for_each_thread(task, pos) {
3826 if (!nr--)
3827 goto found;
3828 }
3829fail:
3830 pos = NULL;
3831 goto out;
3832found:
3833 get_task_struct(pos);
3834out:
3835 rcu_read_unlock();
3836 return pos;
3837}
3838
3839/*
3840 * Find the next thread in the thread list.
3841 * Return NULL if there is an error or no next thread.
3842 *
3843 * The reference to the input task_struct is released.
3844 */
3845static struct task_struct *next_tid(struct task_struct *start)
3846{
3847 struct task_struct *pos = NULL;
3848 rcu_read_lock();
3849 if (pid_alive(start)) {
3850 pos = __next_thread(start);
3851 if (pos)
3852 get_task_struct(pos);
3853 }
3854 rcu_read_unlock();
3855 put_task_struct(start);
3856 return pos;
3857}
3858
3859/* for the /proc/TGID/task/ directories */
3860static int proc_task_readdir(struct file *file, struct dir_context *ctx)
3861{
3862 struct inode *inode = file_inode(file);
3863 struct task_struct *task;
3864 struct pid_namespace *ns;
3865 int tid;
3866
3867 if (proc_inode_is_dead(inode))
3868 return -ENOENT;
3869
3870 if (!dir_emit_dots(file, ctx))
3871 return 0;
3872
3873 /* f_version caches the tgid value that the last readdir call couldn't
3874 * return. lseek aka telldir automagically resets f_version to 0.
3875 */
3876 ns = proc_pid_ns(inode->i_sb);
3877 tid = (int)file->f_version;
3878 file->f_version = 0;
3879 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
3880 task;
3881 task = next_tid(task), ctx->pos++) {
3882 char name[10 + 1];
3883 unsigned int len;
3884
3885 tid = task_pid_nr_ns(task, ns);
3886 if (!tid)
3887 continue; /* The task has just exited. */
3888 len = snprintf(name, sizeof(name), "%u", tid);
3889 if (!proc_fill_cache(file, ctx, name, len,
3890 proc_task_instantiate, task, NULL)) {
3891 /* returning this tgid failed, save it as the first
3892 * pid for the next readir call */
3893 file->f_version = (u64)tid;
3894 put_task_struct(task);
3895 break;
3896 }
3897 }
3898
3899 return 0;
3900}
3901
3902static int proc_task_getattr(struct mnt_idmap *idmap,
3903 const struct path *path, struct kstat *stat,
3904 u32 request_mask, unsigned int query_flags)
3905{
3906 struct inode *inode = d_inode(path->dentry);
3907 struct task_struct *p = get_proc_task(inode);
3908 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
3909
3910 if (p) {
3911 stat->nlink += get_nr_threads(p);
3912 put_task_struct(p);
3913 }
3914
3915 return 0;
3916}
3917
3918static const struct inode_operations proc_task_inode_operations = {
3919 .lookup = proc_task_lookup,
3920 .getattr = proc_task_getattr,
3921 .setattr = proc_setattr,
3922 .permission = proc_pid_permission,
3923};
3924
3925static const struct file_operations proc_task_operations = {
3926 .read = generic_read_dir,
3927 .iterate_shared = proc_task_readdir,
3928 .llseek = generic_file_llseek,
3929};
3930
3931void __init set_proc_pid_nlink(void)
3932{
3933 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3934 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3935}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/proc/base.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 *
7 * proc base directory handling functions
8 *
9 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
10 * Instead of using magical inumbers to determine the kind of object
11 * we allocate and fill in-core inodes upon lookup. They don't even
12 * go into icache. We cache the reference to task_struct upon lookup too.
13 * Eventually it should become a filesystem in its own. We don't use the
14 * rest of procfs anymore.
15 *
16 *
17 * Changelog:
18 * 17-Jan-2005
19 * Allan Bezerra
20 * Bruna Moreira <bruna.moreira@indt.org.br>
21 * Edjard Mota <edjard.mota@indt.org.br>
22 * Ilias Biris <ilias.biris@indt.org.br>
23 * Mauricio Lin <mauricio.lin@indt.org.br>
24 *
25 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
26 *
27 * A new process specific entry (smaps) included in /proc. It shows the
28 * size of rss for each memory area. The maps entry lacks information
29 * about physical memory size (rss) for each mapped file, i.e.,
30 * rss information for executables and library files.
31 * This additional information is useful for any tools that need to know
32 * about physical memory consumption for a process specific library.
33 *
34 * Changelog:
35 * 21-Feb-2005
36 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
37 * Pud inclusion in the page table walking.
38 *
39 * ChangeLog:
40 * 10-Mar-2005
41 * 10LE Instituto Nokia de Tecnologia - INdT:
42 * A better way to walks through the page table as suggested by Hugh Dickins.
43 *
44 * Simo Piiroinen <simo.piiroinen@nokia.com>:
45 * Smaps information related to shared, private, clean and dirty pages.
46 *
47 * Paul Mundt <paul.mundt@nokia.com>:
48 * Overall revision about smaps.
49 */
50
51#include <linux/uaccess.h>
52
53#include <linux/errno.h>
54#include <linux/time.h>
55#include <linux/proc_fs.h>
56#include <linux/stat.h>
57#include <linux/task_io_accounting_ops.h>
58#include <linux/init.h>
59#include <linux/capability.h>
60#include <linux/file.h>
61#include <linux/fdtable.h>
62#include <linux/string.h>
63#include <linux/seq_file.h>
64#include <linux/namei.h>
65#include <linux/mnt_namespace.h>
66#include <linux/mm.h>
67#include <linux/swap.h>
68#include <linux/rcupdate.h>
69#include <linux/kallsyms.h>
70#include <linux/stacktrace.h>
71#include <linux/resource.h>
72#include <linux/module.h>
73#include <linux/mount.h>
74#include <linux/security.h>
75#include <linux/ptrace.h>
76#include <linux/tracehook.h>
77#include <linux/printk.h>
78#include <linux/cache.h>
79#include <linux/cgroup.h>
80#include <linux/cpuset.h>
81#include <linux/audit.h>
82#include <linux/poll.h>
83#include <linux/nsproxy.h>
84#include <linux/oom.h>
85#include <linux/elf.h>
86#include <linux/pid_namespace.h>
87#include <linux/user_namespace.h>
88#include <linux/fs_struct.h>
89#include <linux/slab.h>
90#include <linux/sched/autogroup.h>
91#include <linux/sched/mm.h>
92#include <linux/sched/coredump.h>
93#include <linux/sched/debug.h>
94#include <linux/sched/stat.h>
95#include <linux/flex_array.h>
96#include <linux/posix-timers.h>
97#include <trace/events/oom.h>
98#include "internal.h"
99#include "fd.h"
100
101#include "../../lib/kstrtox.h"
102
103/* NOTE:
104 * Implementing inode permission operations in /proc is almost
105 * certainly an error. Permission checks need to happen during
106 * each system call not at open time. The reason is that most of
107 * what we wish to check for permissions in /proc varies at runtime.
108 *
109 * The classic example of a problem is opening file descriptors
110 * in /proc for a task before it execs a suid executable.
111 */
112
113static u8 nlink_tid __ro_after_init;
114static u8 nlink_tgid __ro_after_init;
115
116struct pid_entry {
117 const char *name;
118 unsigned int len;
119 umode_t mode;
120 const struct inode_operations *iop;
121 const struct file_operations *fop;
122 union proc_op op;
123};
124
125#define NOD(NAME, MODE, IOP, FOP, OP) { \
126 .name = (NAME), \
127 .len = sizeof(NAME) - 1, \
128 .mode = MODE, \
129 .iop = IOP, \
130 .fop = FOP, \
131 .op = OP, \
132}
133
134#define DIR(NAME, MODE, iops, fops) \
135 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
136#define LNK(NAME, get_link) \
137 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
138 &proc_pid_link_inode_operations, NULL, \
139 { .proc_get_link = get_link } )
140#define REG(NAME, MODE, fops) \
141 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
142#define ONE(NAME, MODE, show) \
143 NOD(NAME, (S_IFREG|(MODE)), \
144 NULL, &proc_single_file_operations, \
145 { .proc_show = show } )
146
147/*
148 * Count the number of hardlinks for the pid_entry table, excluding the .
149 * and .. links.
150 */
151static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,
152 unsigned int n)
153{
154 unsigned int i;
155 unsigned int count;
156
157 count = 2;
158 for (i = 0; i < n; ++i) {
159 if (S_ISDIR(entries[i].mode))
160 ++count;
161 }
162
163 return count;
164}
165
166static int get_task_root(struct task_struct *task, struct path *root)
167{
168 int result = -ENOENT;
169
170 task_lock(task);
171 if (task->fs) {
172 get_fs_root(task->fs, root);
173 result = 0;
174 }
175 task_unlock(task);
176 return result;
177}
178
179static int proc_cwd_link(struct dentry *dentry, struct path *path)
180{
181 struct task_struct *task = get_proc_task(d_inode(dentry));
182 int result = -ENOENT;
183
184 if (task) {
185 task_lock(task);
186 if (task->fs) {
187 get_fs_pwd(task->fs, path);
188 result = 0;
189 }
190 task_unlock(task);
191 put_task_struct(task);
192 }
193 return result;
194}
195
196static int proc_root_link(struct dentry *dentry, struct path *path)
197{
198 struct task_struct *task = get_proc_task(d_inode(dentry));
199 int result = -ENOENT;
200
201 if (task) {
202 result = get_task_root(task, path);
203 put_task_struct(task);
204 }
205 return result;
206}
207
208static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
209 size_t _count, loff_t *pos)
210{
211 struct task_struct *tsk;
212 struct mm_struct *mm;
213 char *page;
214 unsigned long count = _count;
215 unsigned long arg_start, arg_end, env_start, env_end;
216 unsigned long len1, len2, len;
217 unsigned long p;
218 char c;
219 ssize_t rv;
220
221 BUG_ON(*pos < 0);
222
223 tsk = get_proc_task(file_inode(file));
224 if (!tsk)
225 return -ESRCH;
226 mm = get_task_mm(tsk);
227 put_task_struct(tsk);
228 if (!mm)
229 return 0;
230 /* Check if process spawned far enough to have cmdline. */
231 if (!mm->env_end) {
232 rv = 0;
233 goto out_mmput;
234 }
235
236 page = (char *)__get_free_page(GFP_KERNEL);
237 if (!page) {
238 rv = -ENOMEM;
239 goto out_mmput;
240 }
241
242 down_read(&mm->mmap_sem);
243 arg_start = mm->arg_start;
244 arg_end = mm->arg_end;
245 env_start = mm->env_start;
246 env_end = mm->env_end;
247 up_read(&mm->mmap_sem);
248
249 BUG_ON(arg_start > arg_end);
250 BUG_ON(env_start > env_end);
251
252 len1 = arg_end - arg_start;
253 len2 = env_end - env_start;
254
255 /* Empty ARGV. */
256 if (len1 == 0) {
257 rv = 0;
258 goto out_free_page;
259 }
260 /*
261 * Inherently racy -- command line shares address space
262 * with code and data.
263 */
264 rv = access_remote_vm(mm, arg_end - 1, &c, 1, FOLL_ANON);
265 if (rv <= 0)
266 goto out_free_page;
267
268 rv = 0;
269
270 if (c == '\0') {
271 /* Command line (set of strings) occupies whole ARGV. */
272 if (len1 <= *pos)
273 goto out_free_page;
274
275 p = arg_start + *pos;
276 len = len1 - *pos;
277 while (count > 0 && len > 0) {
278 unsigned int _count;
279 int nr_read;
280
281 _count = min3(count, len, PAGE_SIZE);
282 nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
283 if (nr_read < 0)
284 rv = nr_read;
285 if (nr_read <= 0)
286 goto out_free_page;
287
288 if (copy_to_user(buf, page, nr_read)) {
289 rv = -EFAULT;
290 goto out_free_page;
291 }
292
293 p += nr_read;
294 len -= nr_read;
295 buf += nr_read;
296 count -= nr_read;
297 rv += nr_read;
298 }
299 } else {
300 /*
301 * Command line (1 string) occupies ARGV and
302 * extends into ENVP.
303 */
304 struct {
305 unsigned long p;
306 unsigned long len;
307 } cmdline[2] = {
308 { .p = arg_start, .len = len1 },
309 { .p = env_start, .len = len2 },
310 };
311 loff_t pos1 = *pos;
312 unsigned int i;
313
314 i = 0;
315 while (i < 2 && pos1 >= cmdline[i].len) {
316 pos1 -= cmdline[i].len;
317 i++;
318 }
319 while (i < 2) {
320 p = cmdline[i].p + pos1;
321 len = cmdline[i].len - pos1;
322 while (count > 0 && len > 0) {
323 unsigned int _count, l;
324 int nr_read;
325 bool final;
326
327 _count = min3(count, len, PAGE_SIZE);
328 nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
329 if (nr_read < 0)
330 rv = nr_read;
331 if (nr_read <= 0)
332 goto out_free_page;
333
334 /*
335 * Command line can be shorter than whole ARGV
336 * even if last "marker" byte says it is not.
337 */
338 final = false;
339 l = strnlen(page, nr_read);
340 if (l < nr_read) {
341 nr_read = l;
342 final = true;
343 }
344
345 if (copy_to_user(buf, page, nr_read)) {
346 rv = -EFAULT;
347 goto out_free_page;
348 }
349
350 p += nr_read;
351 len -= nr_read;
352 buf += nr_read;
353 count -= nr_read;
354 rv += nr_read;
355
356 if (final)
357 goto out_free_page;
358 }
359
360 /* Only first chunk can be read partially. */
361 pos1 = 0;
362 i++;
363 }
364 }
365
366out_free_page:
367 free_page((unsigned long)page);
368out_mmput:
369 mmput(mm);
370 if (rv > 0)
371 *pos += rv;
372 return rv;
373}
374
375static const struct file_operations proc_pid_cmdline_ops = {
376 .read = proc_pid_cmdline_read,
377 .llseek = generic_file_llseek,
378};
379
380#ifdef CONFIG_KALLSYMS
381/*
382 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
383 * Returns the resolved symbol. If that fails, simply return the address.
384 */
385static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
386 struct pid *pid, struct task_struct *task)
387{
388 unsigned long wchan;
389 char symname[KSYM_NAME_LEN];
390
391 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
392 goto print0;
393
394 wchan = get_wchan(task);
395 if (wchan && !lookup_symbol_name(wchan, symname)) {
396 seq_puts(m, symname);
397 return 0;
398 }
399
400print0:
401 seq_putc(m, '0');
402 return 0;
403}
404#endif /* CONFIG_KALLSYMS */
405
406static int lock_trace(struct task_struct *task)
407{
408 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
409 if (err)
410 return err;
411 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
412 mutex_unlock(&task->signal->cred_guard_mutex);
413 return -EPERM;
414 }
415 return 0;
416}
417
418static void unlock_trace(struct task_struct *task)
419{
420 mutex_unlock(&task->signal->cred_guard_mutex);
421}
422
423#ifdef CONFIG_STACKTRACE
424
425#define MAX_STACK_TRACE_DEPTH 64
426
427static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
428 struct pid *pid, struct task_struct *task)
429{
430 struct stack_trace trace;
431 unsigned long *entries;
432 int err;
433 int i;
434
435 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
436 if (!entries)
437 return -ENOMEM;
438
439 trace.nr_entries = 0;
440 trace.max_entries = MAX_STACK_TRACE_DEPTH;
441 trace.entries = entries;
442 trace.skip = 0;
443
444 err = lock_trace(task);
445 if (!err) {
446 save_stack_trace_tsk(task, &trace);
447
448 for (i = 0; i < trace.nr_entries; i++) {
449 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]);
450 }
451 unlock_trace(task);
452 }
453 kfree(entries);
454
455 return err;
456}
457#endif
458
459#ifdef CONFIG_SCHED_INFO
460/*
461 * Provides /proc/PID/schedstat
462 */
463static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
464 struct pid *pid, struct task_struct *task)
465{
466 if (unlikely(!sched_info_on()))
467 seq_printf(m, "0 0 0\n");
468 else
469 seq_printf(m, "%llu %llu %lu\n",
470 (unsigned long long)task->se.sum_exec_runtime,
471 (unsigned long long)task->sched_info.run_delay,
472 task->sched_info.pcount);
473
474 return 0;
475}
476#endif
477
478#ifdef CONFIG_LATENCYTOP
479static int lstats_show_proc(struct seq_file *m, void *v)
480{
481 int i;
482 struct inode *inode = m->private;
483 struct task_struct *task = get_proc_task(inode);
484
485 if (!task)
486 return -ESRCH;
487 seq_puts(m, "Latency Top version : v0.1\n");
488 for (i = 0; i < 32; i++) {
489 struct latency_record *lr = &task->latency_record[i];
490 if (lr->backtrace[0]) {
491 int q;
492 seq_printf(m, "%i %li %li",
493 lr->count, lr->time, lr->max);
494 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
495 unsigned long bt = lr->backtrace[q];
496 if (!bt)
497 break;
498 if (bt == ULONG_MAX)
499 break;
500 seq_printf(m, " %ps", (void *)bt);
501 }
502 seq_putc(m, '\n');
503 }
504
505 }
506 put_task_struct(task);
507 return 0;
508}
509
510static int lstats_open(struct inode *inode, struct file *file)
511{
512 return single_open(file, lstats_show_proc, inode);
513}
514
515static ssize_t lstats_write(struct file *file, const char __user *buf,
516 size_t count, loff_t *offs)
517{
518 struct task_struct *task = get_proc_task(file_inode(file));
519
520 if (!task)
521 return -ESRCH;
522 clear_all_latency_tracing(task);
523 put_task_struct(task);
524
525 return count;
526}
527
528static const struct file_operations proc_lstats_operations = {
529 .open = lstats_open,
530 .read = seq_read,
531 .write = lstats_write,
532 .llseek = seq_lseek,
533 .release = single_release,
534};
535
536#endif
537
538static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
539 struct pid *pid, struct task_struct *task)
540{
541 unsigned long totalpages = totalram_pages + total_swap_pages;
542 unsigned long points = 0;
543
544 points = oom_badness(task, NULL, NULL, totalpages) *
545 1000 / totalpages;
546 seq_printf(m, "%lu\n", points);
547
548 return 0;
549}
550
551struct limit_names {
552 const char *name;
553 const char *unit;
554};
555
556static const struct limit_names lnames[RLIM_NLIMITS] = {
557 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
558 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
559 [RLIMIT_DATA] = {"Max data size", "bytes"},
560 [RLIMIT_STACK] = {"Max stack size", "bytes"},
561 [RLIMIT_CORE] = {"Max core file size", "bytes"},
562 [RLIMIT_RSS] = {"Max resident set", "bytes"},
563 [RLIMIT_NPROC] = {"Max processes", "processes"},
564 [RLIMIT_NOFILE] = {"Max open files", "files"},
565 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
566 [RLIMIT_AS] = {"Max address space", "bytes"},
567 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
568 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
569 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
570 [RLIMIT_NICE] = {"Max nice priority", NULL},
571 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
572 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
573};
574
575/* Display limits for a process */
576static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
577 struct pid *pid, struct task_struct *task)
578{
579 unsigned int i;
580 unsigned long flags;
581
582 struct rlimit rlim[RLIM_NLIMITS];
583
584 if (!lock_task_sighand(task, &flags))
585 return 0;
586 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
587 unlock_task_sighand(task, &flags);
588
589 /*
590 * print the file header
591 */
592 seq_printf(m, "%-25s %-20s %-20s %-10s\n",
593 "Limit", "Soft Limit", "Hard Limit", "Units");
594
595 for (i = 0; i < RLIM_NLIMITS; i++) {
596 if (rlim[i].rlim_cur == RLIM_INFINITY)
597 seq_printf(m, "%-25s %-20s ",
598 lnames[i].name, "unlimited");
599 else
600 seq_printf(m, "%-25s %-20lu ",
601 lnames[i].name, rlim[i].rlim_cur);
602
603 if (rlim[i].rlim_max == RLIM_INFINITY)
604 seq_printf(m, "%-20s ", "unlimited");
605 else
606 seq_printf(m, "%-20lu ", rlim[i].rlim_max);
607
608 if (lnames[i].unit)
609 seq_printf(m, "%-10s\n", lnames[i].unit);
610 else
611 seq_putc(m, '\n');
612 }
613
614 return 0;
615}
616
617#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
618static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
619 struct pid *pid, struct task_struct *task)
620{
621 long nr;
622 unsigned long args[6], sp, pc;
623 int res;
624
625 res = lock_trace(task);
626 if (res)
627 return res;
628
629 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
630 seq_puts(m, "running\n");
631 else if (nr < 0)
632 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
633 else
634 seq_printf(m,
635 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
636 nr,
637 args[0], args[1], args[2], args[3], args[4], args[5],
638 sp, pc);
639 unlock_trace(task);
640
641 return 0;
642}
643#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
644
645/************************************************************************/
646/* Here the fs part begins */
647/************************************************************************/
648
649/* permission checks */
650static int proc_fd_access_allowed(struct inode *inode)
651{
652 struct task_struct *task;
653 int allowed = 0;
654 /* Allow access to a task's file descriptors if it is us or we
655 * may use ptrace attach to the process and find out that
656 * information.
657 */
658 task = get_proc_task(inode);
659 if (task) {
660 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
661 put_task_struct(task);
662 }
663 return allowed;
664}
665
666int proc_setattr(struct dentry *dentry, struct iattr *attr)
667{
668 int error;
669 struct inode *inode = d_inode(dentry);
670
671 if (attr->ia_valid & ATTR_MODE)
672 return -EPERM;
673
674 error = setattr_prepare(dentry, attr);
675 if (error)
676 return error;
677
678 setattr_copy(inode, attr);
679 mark_inode_dirty(inode);
680 return 0;
681}
682
683/*
684 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
685 * or euid/egid (for hide_pid_min=2)?
686 */
687static bool has_pid_permissions(struct pid_namespace *pid,
688 struct task_struct *task,
689 int hide_pid_min)
690{
691 if (pid->hide_pid < hide_pid_min)
692 return true;
693 if (in_group_p(pid->pid_gid))
694 return true;
695 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
696}
697
698
699static int proc_pid_permission(struct inode *inode, int mask)
700{
701 struct pid_namespace *pid = inode->i_sb->s_fs_info;
702 struct task_struct *task;
703 bool has_perms;
704
705 task = get_proc_task(inode);
706 if (!task)
707 return -ESRCH;
708 has_perms = has_pid_permissions(pid, task, HIDEPID_NO_ACCESS);
709 put_task_struct(task);
710
711 if (!has_perms) {
712 if (pid->hide_pid == HIDEPID_INVISIBLE) {
713 /*
714 * Let's make getdents(), stat(), and open()
715 * consistent with each other. If a process
716 * may not stat() a file, it shouldn't be seen
717 * in procfs at all.
718 */
719 return -ENOENT;
720 }
721
722 return -EPERM;
723 }
724 return generic_permission(inode, mask);
725}
726
727
728
729static const struct inode_operations proc_def_inode_operations = {
730 .setattr = proc_setattr,
731};
732
733static int proc_single_show(struct seq_file *m, void *v)
734{
735 struct inode *inode = m->private;
736 struct pid_namespace *ns;
737 struct pid *pid;
738 struct task_struct *task;
739 int ret;
740
741 ns = inode->i_sb->s_fs_info;
742 pid = proc_pid(inode);
743 task = get_pid_task(pid, PIDTYPE_PID);
744 if (!task)
745 return -ESRCH;
746
747 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
748
749 put_task_struct(task);
750 return ret;
751}
752
753static int proc_single_open(struct inode *inode, struct file *filp)
754{
755 return single_open(filp, proc_single_show, inode);
756}
757
758static const struct file_operations proc_single_file_operations = {
759 .open = proc_single_open,
760 .read = seq_read,
761 .llseek = seq_lseek,
762 .release = single_release,
763};
764
765
766struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
767{
768 struct task_struct *task = get_proc_task(inode);
769 struct mm_struct *mm = ERR_PTR(-ESRCH);
770
771 if (task) {
772 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
773 put_task_struct(task);
774
775 if (!IS_ERR_OR_NULL(mm)) {
776 /* ensure this mm_struct can't be freed */
777 mmgrab(mm);
778 /* but do not pin its memory */
779 mmput(mm);
780 }
781 }
782
783 return mm;
784}
785
786static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
787{
788 struct mm_struct *mm = proc_mem_open(inode, mode);
789
790 if (IS_ERR(mm))
791 return PTR_ERR(mm);
792
793 file->private_data = mm;
794 return 0;
795}
796
797static int mem_open(struct inode *inode, struct file *file)
798{
799 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
800
801 /* OK to pass negative loff_t, we can catch out-of-range */
802 file->f_mode |= FMODE_UNSIGNED_OFFSET;
803
804 return ret;
805}
806
807static ssize_t mem_rw(struct file *file, char __user *buf,
808 size_t count, loff_t *ppos, int write)
809{
810 struct mm_struct *mm = file->private_data;
811 unsigned long addr = *ppos;
812 ssize_t copied;
813 char *page;
814 unsigned int flags;
815
816 if (!mm)
817 return 0;
818
819 page = (char *)__get_free_page(GFP_KERNEL);
820 if (!page)
821 return -ENOMEM;
822
823 copied = 0;
824 if (!mmget_not_zero(mm))
825 goto free;
826
827 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0);
828
829 while (count > 0) {
830 int this_len = min_t(int, count, PAGE_SIZE);
831
832 if (write && copy_from_user(page, buf, this_len)) {
833 copied = -EFAULT;
834 break;
835 }
836
837 this_len = access_remote_vm(mm, addr, page, this_len, flags);
838 if (!this_len) {
839 if (!copied)
840 copied = -EIO;
841 break;
842 }
843
844 if (!write && copy_to_user(buf, page, this_len)) {
845 copied = -EFAULT;
846 break;
847 }
848
849 buf += this_len;
850 addr += this_len;
851 copied += this_len;
852 count -= this_len;
853 }
854 *ppos = addr;
855
856 mmput(mm);
857free:
858 free_page((unsigned long) page);
859 return copied;
860}
861
862static ssize_t mem_read(struct file *file, char __user *buf,
863 size_t count, loff_t *ppos)
864{
865 return mem_rw(file, buf, count, ppos, 0);
866}
867
868static ssize_t mem_write(struct file *file, const char __user *buf,
869 size_t count, loff_t *ppos)
870{
871 return mem_rw(file, (char __user*)buf, count, ppos, 1);
872}
873
874loff_t mem_lseek(struct file *file, loff_t offset, int orig)
875{
876 switch (orig) {
877 case 0:
878 file->f_pos = offset;
879 break;
880 case 1:
881 file->f_pos += offset;
882 break;
883 default:
884 return -EINVAL;
885 }
886 force_successful_syscall_return();
887 return file->f_pos;
888}
889
890static int mem_release(struct inode *inode, struct file *file)
891{
892 struct mm_struct *mm = file->private_data;
893 if (mm)
894 mmdrop(mm);
895 return 0;
896}
897
898static const struct file_operations proc_mem_operations = {
899 .llseek = mem_lseek,
900 .read = mem_read,
901 .write = mem_write,
902 .open = mem_open,
903 .release = mem_release,
904};
905
906static int environ_open(struct inode *inode, struct file *file)
907{
908 return __mem_open(inode, file, PTRACE_MODE_READ);
909}
910
911static ssize_t environ_read(struct file *file, char __user *buf,
912 size_t count, loff_t *ppos)
913{
914 char *page;
915 unsigned long src = *ppos;
916 int ret = 0;
917 struct mm_struct *mm = file->private_data;
918 unsigned long env_start, env_end;
919
920 /* Ensure the process spawned far enough to have an environment. */
921 if (!mm || !mm->env_end)
922 return 0;
923
924 page = (char *)__get_free_page(GFP_KERNEL);
925 if (!page)
926 return -ENOMEM;
927
928 ret = 0;
929 if (!mmget_not_zero(mm))
930 goto free;
931
932 down_read(&mm->mmap_sem);
933 env_start = mm->env_start;
934 env_end = mm->env_end;
935 up_read(&mm->mmap_sem);
936
937 while (count > 0) {
938 size_t this_len, max_len;
939 int retval;
940
941 if (src >= (env_end - env_start))
942 break;
943
944 this_len = env_end - (env_start + src);
945
946 max_len = min_t(size_t, PAGE_SIZE, count);
947 this_len = min(max_len, this_len);
948
949 retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON);
950
951 if (retval <= 0) {
952 ret = retval;
953 break;
954 }
955
956 if (copy_to_user(buf, page, retval)) {
957 ret = -EFAULT;
958 break;
959 }
960
961 ret += retval;
962 src += retval;
963 buf += retval;
964 count -= retval;
965 }
966 *ppos = src;
967 mmput(mm);
968
969free:
970 free_page((unsigned long) page);
971 return ret;
972}
973
974static const struct file_operations proc_environ_operations = {
975 .open = environ_open,
976 .read = environ_read,
977 .llseek = generic_file_llseek,
978 .release = mem_release,
979};
980
981static int auxv_open(struct inode *inode, struct file *file)
982{
983 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
984}
985
986static ssize_t auxv_read(struct file *file, char __user *buf,
987 size_t count, loff_t *ppos)
988{
989 struct mm_struct *mm = file->private_data;
990 unsigned int nwords = 0;
991
992 if (!mm)
993 return 0;
994 do {
995 nwords += 2;
996 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
997 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,
998 nwords * sizeof(mm->saved_auxv[0]));
999}
1000
1001static const struct file_operations proc_auxv_operations = {
1002 .open = auxv_open,
1003 .read = auxv_read,
1004 .llseek = generic_file_llseek,
1005 .release = mem_release,
1006};
1007
1008static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1009 loff_t *ppos)
1010{
1011 struct task_struct *task = get_proc_task(file_inode(file));
1012 char buffer[PROC_NUMBUF];
1013 int oom_adj = OOM_ADJUST_MIN;
1014 size_t len;
1015
1016 if (!task)
1017 return -ESRCH;
1018 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1019 oom_adj = OOM_ADJUST_MAX;
1020 else
1021 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1022 OOM_SCORE_ADJ_MAX;
1023 put_task_struct(task);
1024 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1025 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1026}
1027
1028static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
1029{
1030 static DEFINE_MUTEX(oom_adj_mutex);
1031 struct mm_struct *mm = NULL;
1032 struct task_struct *task;
1033 int err = 0;
1034
1035 task = get_proc_task(file_inode(file));
1036 if (!task)
1037 return -ESRCH;
1038
1039 mutex_lock(&oom_adj_mutex);
1040 if (legacy) {
1041 if (oom_adj < task->signal->oom_score_adj &&
1042 !capable(CAP_SYS_RESOURCE)) {
1043 err = -EACCES;
1044 goto err_unlock;
1045 }
1046 /*
1047 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1048 * /proc/pid/oom_score_adj instead.
1049 */
1050 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1051 current->comm, task_pid_nr(current), task_pid_nr(task),
1052 task_pid_nr(task));
1053 } else {
1054 if ((short)oom_adj < task->signal->oom_score_adj_min &&
1055 !capable(CAP_SYS_RESOURCE)) {
1056 err = -EACCES;
1057 goto err_unlock;
1058 }
1059 }
1060
1061 /*
1062 * Make sure we will check other processes sharing the mm if this is
1063 * not vfrok which wants its own oom_score_adj.
1064 * pin the mm so it doesn't go away and get reused after task_unlock
1065 */
1066 if (!task->vfork_done) {
1067 struct task_struct *p = find_lock_task_mm(task);
1068
1069 if (p) {
1070 if (atomic_read(&p->mm->mm_users) > 1) {
1071 mm = p->mm;
1072 mmgrab(mm);
1073 }
1074 task_unlock(p);
1075 }
1076 }
1077
1078 task->signal->oom_score_adj = oom_adj;
1079 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1080 task->signal->oom_score_adj_min = (short)oom_adj;
1081 trace_oom_score_adj_update(task);
1082
1083 if (mm) {
1084 struct task_struct *p;
1085
1086 rcu_read_lock();
1087 for_each_process(p) {
1088 if (same_thread_group(task, p))
1089 continue;
1090
1091 /* do not touch kernel threads or the global init */
1092 if (p->flags & PF_KTHREAD || is_global_init(p))
1093 continue;
1094
1095 task_lock(p);
1096 if (!p->vfork_done && process_shares_mm(p, mm)) {
1097 pr_info("updating oom_score_adj for %d (%s) from %d to %d because it shares mm with %d (%s). Report if this is unexpected.\n",
1098 task_pid_nr(p), p->comm,
1099 p->signal->oom_score_adj, oom_adj,
1100 task_pid_nr(task), task->comm);
1101 p->signal->oom_score_adj = oom_adj;
1102 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1103 p->signal->oom_score_adj_min = (short)oom_adj;
1104 }
1105 task_unlock(p);
1106 }
1107 rcu_read_unlock();
1108 mmdrop(mm);
1109 }
1110err_unlock:
1111 mutex_unlock(&oom_adj_mutex);
1112 put_task_struct(task);
1113 return err;
1114}
1115
1116/*
1117 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1118 * kernels. The effective policy is defined by oom_score_adj, which has a
1119 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1120 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1121 * Processes that become oom disabled via oom_adj will still be oom disabled
1122 * with this implementation.
1123 *
1124 * oom_adj cannot be removed since existing userspace binaries use it.
1125 */
1126static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1127 size_t count, loff_t *ppos)
1128{
1129 char buffer[PROC_NUMBUF];
1130 int oom_adj;
1131 int err;
1132
1133 memset(buffer, 0, sizeof(buffer));
1134 if (count > sizeof(buffer) - 1)
1135 count = sizeof(buffer) - 1;
1136 if (copy_from_user(buffer, buf, count)) {
1137 err = -EFAULT;
1138 goto out;
1139 }
1140
1141 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1142 if (err)
1143 goto out;
1144 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1145 oom_adj != OOM_DISABLE) {
1146 err = -EINVAL;
1147 goto out;
1148 }
1149
1150 /*
1151 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1152 * value is always attainable.
1153 */
1154 if (oom_adj == OOM_ADJUST_MAX)
1155 oom_adj = OOM_SCORE_ADJ_MAX;
1156 else
1157 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1158
1159 err = __set_oom_adj(file, oom_adj, true);
1160out:
1161 return err < 0 ? err : count;
1162}
1163
1164static const struct file_operations proc_oom_adj_operations = {
1165 .read = oom_adj_read,
1166 .write = oom_adj_write,
1167 .llseek = generic_file_llseek,
1168};
1169
1170static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1171 size_t count, loff_t *ppos)
1172{
1173 struct task_struct *task = get_proc_task(file_inode(file));
1174 char buffer[PROC_NUMBUF];
1175 short oom_score_adj = OOM_SCORE_ADJ_MIN;
1176 size_t len;
1177
1178 if (!task)
1179 return -ESRCH;
1180 oom_score_adj = task->signal->oom_score_adj;
1181 put_task_struct(task);
1182 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
1183 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1184}
1185
1186static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1187 size_t count, loff_t *ppos)
1188{
1189 char buffer[PROC_NUMBUF];
1190 int oom_score_adj;
1191 int err;
1192
1193 memset(buffer, 0, sizeof(buffer));
1194 if (count > sizeof(buffer) - 1)
1195 count = sizeof(buffer) - 1;
1196 if (copy_from_user(buffer, buf, count)) {
1197 err = -EFAULT;
1198 goto out;
1199 }
1200
1201 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1202 if (err)
1203 goto out;
1204 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1205 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1206 err = -EINVAL;
1207 goto out;
1208 }
1209
1210 err = __set_oom_adj(file, oom_score_adj, false);
1211out:
1212 return err < 0 ? err : count;
1213}
1214
1215static const struct file_operations proc_oom_score_adj_operations = {
1216 .read = oom_score_adj_read,
1217 .write = oom_score_adj_write,
1218 .llseek = default_llseek,
1219};
1220
1221#ifdef CONFIG_AUDITSYSCALL
1222#define TMPBUFLEN 11
1223static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1224 size_t count, loff_t *ppos)
1225{
1226 struct inode * inode = file_inode(file);
1227 struct task_struct *task = get_proc_task(inode);
1228 ssize_t length;
1229 char tmpbuf[TMPBUFLEN];
1230
1231 if (!task)
1232 return -ESRCH;
1233 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1234 from_kuid(file->f_cred->user_ns,
1235 audit_get_loginuid(task)));
1236 put_task_struct(task);
1237 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1238}
1239
1240static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1241 size_t count, loff_t *ppos)
1242{
1243 struct inode * inode = file_inode(file);
1244 uid_t loginuid;
1245 kuid_t kloginuid;
1246 int rv;
1247
1248 rcu_read_lock();
1249 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1250 rcu_read_unlock();
1251 return -EPERM;
1252 }
1253 rcu_read_unlock();
1254
1255 if (*ppos != 0) {
1256 /* No partial writes. */
1257 return -EINVAL;
1258 }
1259
1260 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1261 if (rv < 0)
1262 return rv;
1263
1264 /* is userspace tring to explicitly UNSET the loginuid? */
1265 if (loginuid == AUDIT_UID_UNSET) {
1266 kloginuid = INVALID_UID;
1267 } else {
1268 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
1269 if (!uid_valid(kloginuid))
1270 return -EINVAL;
1271 }
1272
1273 rv = audit_set_loginuid(kloginuid);
1274 if (rv < 0)
1275 return rv;
1276 return count;
1277}
1278
1279static const struct file_operations proc_loginuid_operations = {
1280 .read = proc_loginuid_read,
1281 .write = proc_loginuid_write,
1282 .llseek = generic_file_llseek,
1283};
1284
1285static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1286 size_t count, loff_t *ppos)
1287{
1288 struct inode * inode = file_inode(file);
1289 struct task_struct *task = get_proc_task(inode);
1290 ssize_t length;
1291 char tmpbuf[TMPBUFLEN];
1292
1293 if (!task)
1294 return -ESRCH;
1295 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1296 audit_get_sessionid(task));
1297 put_task_struct(task);
1298 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1299}
1300
1301static const struct file_operations proc_sessionid_operations = {
1302 .read = proc_sessionid_read,
1303 .llseek = generic_file_llseek,
1304};
1305#endif
1306
1307#ifdef CONFIG_FAULT_INJECTION
1308static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1309 size_t count, loff_t *ppos)
1310{
1311 struct task_struct *task = get_proc_task(file_inode(file));
1312 char buffer[PROC_NUMBUF];
1313 size_t len;
1314 int make_it_fail;
1315
1316 if (!task)
1317 return -ESRCH;
1318 make_it_fail = task->make_it_fail;
1319 put_task_struct(task);
1320
1321 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1322
1323 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1324}
1325
1326static ssize_t proc_fault_inject_write(struct file * file,
1327 const char __user * buf, size_t count, loff_t *ppos)
1328{
1329 struct task_struct *task;
1330 char buffer[PROC_NUMBUF];
1331 int make_it_fail;
1332 int rv;
1333
1334 if (!capable(CAP_SYS_RESOURCE))
1335 return -EPERM;
1336 memset(buffer, 0, sizeof(buffer));
1337 if (count > sizeof(buffer) - 1)
1338 count = sizeof(buffer) - 1;
1339 if (copy_from_user(buffer, buf, count))
1340 return -EFAULT;
1341 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1342 if (rv < 0)
1343 return rv;
1344 if (make_it_fail < 0 || make_it_fail > 1)
1345 return -EINVAL;
1346
1347 task = get_proc_task(file_inode(file));
1348 if (!task)
1349 return -ESRCH;
1350 task->make_it_fail = make_it_fail;
1351 put_task_struct(task);
1352
1353 return count;
1354}
1355
1356static const struct file_operations proc_fault_inject_operations = {
1357 .read = proc_fault_inject_read,
1358 .write = proc_fault_inject_write,
1359 .llseek = generic_file_llseek,
1360};
1361
1362static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf,
1363 size_t count, loff_t *ppos)
1364{
1365 struct task_struct *task;
1366 int err;
1367 unsigned int n;
1368
1369 err = kstrtouint_from_user(buf, count, 0, &n);
1370 if (err)
1371 return err;
1372
1373 task = get_proc_task(file_inode(file));
1374 if (!task)
1375 return -ESRCH;
1376 task->fail_nth = n;
1377 put_task_struct(task);
1378
1379 return count;
1380}
1381
1382static ssize_t proc_fail_nth_read(struct file *file, char __user *buf,
1383 size_t count, loff_t *ppos)
1384{
1385 struct task_struct *task;
1386 char numbuf[PROC_NUMBUF];
1387 ssize_t len;
1388
1389 task = get_proc_task(file_inode(file));
1390 if (!task)
1391 return -ESRCH;
1392 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth);
1393 len = simple_read_from_buffer(buf, count, ppos, numbuf, len);
1394 put_task_struct(task);
1395
1396 return len;
1397}
1398
1399static const struct file_operations proc_fail_nth_operations = {
1400 .read = proc_fail_nth_read,
1401 .write = proc_fail_nth_write,
1402};
1403#endif
1404
1405
1406#ifdef CONFIG_SCHED_DEBUG
1407/*
1408 * Print out various scheduling related per-task fields:
1409 */
1410static int sched_show(struct seq_file *m, void *v)
1411{
1412 struct inode *inode = m->private;
1413 struct pid_namespace *ns = inode->i_sb->s_fs_info;
1414 struct task_struct *p;
1415
1416 p = get_proc_task(inode);
1417 if (!p)
1418 return -ESRCH;
1419 proc_sched_show_task(p, ns, m);
1420
1421 put_task_struct(p);
1422
1423 return 0;
1424}
1425
1426static ssize_t
1427sched_write(struct file *file, const char __user *buf,
1428 size_t count, loff_t *offset)
1429{
1430 struct inode *inode = file_inode(file);
1431 struct task_struct *p;
1432
1433 p = get_proc_task(inode);
1434 if (!p)
1435 return -ESRCH;
1436 proc_sched_set_task(p);
1437
1438 put_task_struct(p);
1439
1440 return count;
1441}
1442
1443static int sched_open(struct inode *inode, struct file *filp)
1444{
1445 return single_open(filp, sched_show, inode);
1446}
1447
1448static const struct file_operations proc_pid_sched_operations = {
1449 .open = sched_open,
1450 .read = seq_read,
1451 .write = sched_write,
1452 .llseek = seq_lseek,
1453 .release = single_release,
1454};
1455
1456#endif
1457
1458#ifdef CONFIG_SCHED_AUTOGROUP
1459/*
1460 * Print out autogroup related information:
1461 */
1462static int sched_autogroup_show(struct seq_file *m, void *v)
1463{
1464 struct inode *inode = m->private;
1465 struct task_struct *p;
1466
1467 p = get_proc_task(inode);
1468 if (!p)
1469 return -ESRCH;
1470 proc_sched_autogroup_show_task(p, m);
1471
1472 put_task_struct(p);
1473
1474 return 0;
1475}
1476
1477static ssize_t
1478sched_autogroup_write(struct file *file, const char __user *buf,
1479 size_t count, loff_t *offset)
1480{
1481 struct inode *inode = file_inode(file);
1482 struct task_struct *p;
1483 char buffer[PROC_NUMBUF];
1484 int nice;
1485 int err;
1486
1487 memset(buffer, 0, sizeof(buffer));
1488 if (count > sizeof(buffer) - 1)
1489 count = sizeof(buffer) - 1;
1490 if (copy_from_user(buffer, buf, count))
1491 return -EFAULT;
1492
1493 err = kstrtoint(strstrip(buffer), 0, &nice);
1494 if (err < 0)
1495 return err;
1496
1497 p = get_proc_task(inode);
1498 if (!p)
1499 return -ESRCH;
1500
1501 err = proc_sched_autogroup_set_nice(p, nice);
1502 if (err)
1503 count = err;
1504
1505 put_task_struct(p);
1506
1507 return count;
1508}
1509
1510static int sched_autogroup_open(struct inode *inode, struct file *filp)
1511{
1512 int ret;
1513
1514 ret = single_open(filp, sched_autogroup_show, NULL);
1515 if (!ret) {
1516 struct seq_file *m = filp->private_data;
1517
1518 m->private = inode;
1519 }
1520 return ret;
1521}
1522
1523static const struct file_operations proc_pid_sched_autogroup_operations = {
1524 .open = sched_autogroup_open,
1525 .read = seq_read,
1526 .write = sched_autogroup_write,
1527 .llseek = seq_lseek,
1528 .release = single_release,
1529};
1530
1531#endif /* CONFIG_SCHED_AUTOGROUP */
1532
1533static ssize_t comm_write(struct file *file, const char __user *buf,
1534 size_t count, loff_t *offset)
1535{
1536 struct inode *inode = file_inode(file);
1537 struct task_struct *p;
1538 char buffer[TASK_COMM_LEN];
1539 const size_t maxlen = sizeof(buffer) - 1;
1540
1541 memset(buffer, 0, sizeof(buffer));
1542 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
1543 return -EFAULT;
1544
1545 p = get_proc_task(inode);
1546 if (!p)
1547 return -ESRCH;
1548
1549 if (same_thread_group(current, p))
1550 set_task_comm(p, buffer);
1551 else
1552 count = -EINVAL;
1553
1554 put_task_struct(p);
1555
1556 return count;
1557}
1558
1559static int comm_show(struct seq_file *m, void *v)
1560{
1561 struct inode *inode = m->private;
1562 struct task_struct *p;
1563
1564 p = get_proc_task(inode);
1565 if (!p)
1566 return -ESRCH;
1567
1568 task_lock(p);
1569 seq_printf(m, "%s\n", p->comm);
1570 task_unlock(p);
1571
1572 put_task_struct(p);
1573
1574 return 0;
1575}
1576
1577static int comm_open(struct inode *inode, struct file *filp)
1578{
1579 return single_open(filp, comm_show, inode);
1580}
1581
1582static const struct file_operations proc_pid_set_comm_operations = {
1583 .open = comm_open,
1584 .read = seq_read,
1585 .write = comm_write,
1586 .llseek = seq_lseek,
1587 .release = single_release,
1588};
1589
1590static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1591{
1592 struct task_struct *task;
1593 struct file *exe_file;
1594
1595 task = get_proc_task(d_inode(dentry));
1596 if (!task)
1597 return -ENOENT;
1598 exe_file = get_task_exe_file(task);
1599 put_task_struct(task);
1600 if (exe_file) {
1601 *exe_path = exe_file->f_path;
1602 path_get(&exe_file->f_path);
1603 fput(exe_file);
1604 return 0;
1605 } else
1606 return -ENOENT;
1607}
1608
1609static const char *proc_pid_get_link(struct dentry *dentry,
1610 struct inode *inode,
1611 struct delayed_call *done)
1612{
1613 struct path path;
1614 int error = -EACCES;
1615
1616 if (!dentry)
1617 return ERR_PTR(-ECHILD);
1618
1619 /* Are we allowed to snoop on the tasks file descriptors? */
1620 if (!proc_fd_access_allowed(inode))
1621 goto out;
1622
1623 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1624 if (error)
1625 goto out;
1626
1627 nd_jump_link(&path);
1628 return NULL;
1629out:
1630 return ERR_PTR(error);
1631}
1632
1633static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1634{
1635 char *tmp = (char *)__get_free_page(GFP_KERNEL);
1636 char *pathname;
1637 int len;
1638
1639 if (!tmp)
1640 return -ENOMEM;
1641
1642 pathname = d_path(path, tmp, PAGE_SIZE);
1643 len = PTR_ERR(pathname);
1644 if (IS_ERR(pathname))
1645 goto out;
1646 len = tmp + PAGE_SIZE - 1 - pathname;
1647
1648 if (len > buflen)
1649 len = buflen;
1650 if (copy_to_user(buffer, pathname, len))
1651 len = -EFAULT;
1652 out:
1653 free_page((unsigned long)tmp);
1654 return len;
1655}
1656
1657static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1658{
1659 int error = -EACCES;
1660 struct inode *inode = d_inode(dentry);
1661 struct path path;
1662
1663 /* Are we allowed to snoop on the tasks file descriptors? */
1664 if (!proc_fd_access_allowed(inode))
1665 goto out;
1666
1667 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1668 if (error)
1669 goto out;
1670
1671 error = do_proc_readlink(&path, buffer, buflen);
1672 path_put(&path);
1673out:
1674 return error;
1675}
1676
1677const struct inode_operations proc_pid_link_inode_operations = {
1678 .readlink = proc_pid_readlink,
1679 .get_link = proc_pid_get_link,
1680 .setattr = proc_setattr,
1681};
1682
1683
1684/* building an inode */
1685
1686void task_dump_owner(struct task_struct *task, umode_t mode,
1687 kuid_t *ruid, kgid_t *rgid)
1688{
1689 /* Depending on the state of dumpable compute who should own a
1690 * proc file for a task.
1691 */
1692 const struct cred *cred;
1693 kuid_t uid;
1694 kgid_t gid;
1695
1696 if (unlikely(task->flags & PF_KTHREAD)) {
1697 *ruid = GLOBAL_ROOT_UID;
1698 *rgid = GLOBAL_ROOT_GID;
1699 return;
1700 }
1701
1702 /* Default to the tasks effective ownership */
1703 rcu_read_lock();
1704 cred = __task_cred(task);
1705 uid = cred->euid;
1706 gid = cred->egid;
1707 rcu_read_unlock();
1708
1709 /*
1710 * Before the /proc/pid/status file was created the only way to read
1711 * the effective uid of a /process was to stat /proc/pid. Reading
1712 * /proc/pid/status is slow enough that procps and other packages
1713 * kept stating /proc/pid. To keep the rules in /proc simple I have
1714 * made this apply to all per process world readable and executable
1715 * directories.
1716 */
1717 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) {
1718 struct mm_struct *mm;
1719 task_lock(task);
1720 mm = task->mm;
1721 /* Make non-dumpable tasks owned by some root */
1722 if (mm) {
1723 if (get_dumpable(mm) != SUID_DUMP_USER) {
1724 struct user_namespace *user_ns = mm->user_ns;
1725
1726 uid = make_kuid(user_ns, 0);
1727 if (!uid_valid(uid))
1728 uid = GLOBAL_ROOT_UID;
1729
1730 gid = make_kgid(user_ns, 0);
1731 if (!gid_valid(gid))
1732 gid = GLOBAL_ROOT_GID;
1733 }
1734 } else {
1735 uid = GLOBAL_ROOT_UID;
1736 gid = GLOBAL_ROOT_GID;
1737 }
1738 task_unlock(task);
1739 }
1740 *ruid = uid;
1741 *rgid = gid;
1742}
1743
1744struct inode *proc_pid_make_inode(struct super_block * sb,
1745 struct task_struct *task, umode_t mode)
1746{
1747 struct inode * inode;
1748 struct proc_inode *ei;
1749
1750 /* We need a new inode */
1751
1752 inode = new_inode(sb);
1753 if (!inode)
1754 goto out;
1755
1756 /* Common stuff */
1757 ei = PROC_I(inode);
1758 inode->i_mode = mode;
1759 inode->i_ino = get_next_ino();
1760 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
1761 inode->i_op = &proc_def_inode_operations;
1762
1763 /*
1764 * grab the reference to task.
1765 */
1766 ei->pid = get_task_pid(task, PIDTYPE_PID);
1767 if (!ei->pid)
1768 goto out_unlock;
1769
1770 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1771 security_task_to_inode(task, inode);
1772
1773out:
1774 return inode;
1775
1776out_unlock:
1777 iput(inode);
1778 return NULL;
1779}
1780
1781int pid_getattr(const struct path *path, struct kstat *stat,
1782 u32 request_mask, unsigned int query_flags)
1783{
1784 struct inode *inode = d_inode(path->dentry);
1785 struct task_struct *task;
1786 struct pid_namespace *pid = path->dentry->d_sb->s_fs_info;
1787
1788 generic_fillattr(inode, stat);
1789
1790 rcu_read_lock();
1791 stat->uid = GLOBAL_ROOT_UID;
1792 stat->gid = GLOBAL_ROOT_GID;
1793 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1794 if (task) {
1795 if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) {
1796 rcu_read_unlock();
1797 /*
1798 * This doesn't prevent learning whether PID exists,
1799 * it only makes getattr() consistent with readdir().
1800 */
1801 return -ENOENT;
1802 }
1803 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid);
1804 }
1805 rcu_read_unlock();
1806 return 0;
1807}
1808
1809/* dentry stuff */
1810
1811/*
1812 * Exceptional case: normally we are not allowed to unhash a busy
1813 * directory. In this case, however, we can do it - no aliasing problems
1814 * due to the way we treat inodes.
1815 *
1816 * Rewrite the inode's ownerships here because the owning task may have
1817 * performed a setuid(), etc.
1818 *
1819 */
1820int pid_revalidate(struct dentry *dentry, unsigned int flags)
1821{
1822 struct inode *inode;
1823 struct task_struct *task;
1824
1825 if (flags & LOOKUP_RCU)
1826 return -ECHILD;
1827
1828 inode = d_inode(dentry);
1829 task = get_proc_task(inode);
1830
1831 if (task) {
1832 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
1833
1834 inode->i_mode &= ~(S_ISUID | S_ISGID);
1835 security_task_to_inode(task, inode);
1836 put_task_struct(task);
1837 return 1;
1838 }
1839 return 0;
1840}
1841
1842static inline bool proc_inode_is_dead(struct inode *inode)
1843{
1844 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
1845}
1846
1847int pid_delete_dentry(const struct dentry *dentry)
1848{
1849 /* Is the task we represent dead?
1850 * If so, then don't put the dentry on the lru list,
1851 * kill it immediately.
1852 */
1853 return proc_inode_is_dead(d_inode(dentry));
1854}
1855
1856const struct dentry_operations pid_dentry_operations =
1857{
1858 .d_revalidate = pid_revalidate,
1859 .d_delete = pid_delete_dentry,
1860};
1861
1862/* Lookups */
1863
1864/*
1865 * Fill a directory entry.
1866 *
1867 * If possible create the dcache entry and derive our inode number and
1868 * file type from dcache entry.
1869 *
1870 * Since all of the proc inode numbers are dynamically generated, the inode
1871 * numbers do not exist until the inode is cache. This means creating the
1872 * the dcache entry in readdir is necessary to keep the inode numbers
1873 * reported by readdir in sync with the inode numbers reported
1874 * by stat.
1875 */
1876bool proc_fill_cache(struct file *file, struct dir_context *ctx,
1877 const char *name, int len,
1878 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1879{
1880 struct dentry *child, *dir = file->f_path.dentry;
1881 struct qstr qname = QSTR_INIT(name, len);
1882 struct inode *inode;
1883 unsigned type;
1884 ino_t ino;
1885
1886 child = d_hash_and_lookup(dir, &qname);
1887 if (!child) {
1888 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
1889 child = d_alloc_parallel(dir, &qname, &wq);
1890 if (IS_ERR(child))
1891 goto end_instantiate;
1892 if (d_in_lookup(child)) {
1893 int err = instantiate(d_inode(dir), child, task, ptr);
1894 d_lookup_done(child);
1895 if (err < 0) {
1896 dput(child);
1897 goto end_instantiate;
1898 }
1899 }
1900 }
1901 inode = d_inode(child);
1902 ino = inode->i_ino;
1903 type = inode->i_mode >> 12;
1904 dput(child);
1905 return dir_emit(ctx, name, len, ino, type);
1906
1907end_instantiate:
1908 return dir_emit(ctx, name, len, 1, DT_UNKNOWN);
1909}
1910
1911/*
1912 * dname_to_vma_addr - maps a dentry name into two unsigned longs
1913 * which represent vma start and end addresses.
1914 */
1915static int dname_to_vma_addr(struct dentry *dentry,
1916 unsigned long *start, unsigned long *end)
1917{
1918 const char *str = dentry->d_name.name;
1919 unsigned long long sval, eval;
1920 unsigned int len;
1921
1922 if (str[0] == '0' && str[1] != '-')
1923 return -EINVAL;
1924 len = _parse_integer(str, 16, &sval);
1925 if (len & KSTRTOX_OVERFLOW)
1926 return -EINVAL;
1927 if (sval != (unsigned long)sval)
1928 return -EINVAL;
1929 str += len;
1930
1931 if (*str != '-')
1932 return -EINVAL;
1933 str++;
1934
1935 if (str[0] == '0' && str[1])
1936 return -EINVAL;
1937 len = _parse_integer(str, 16, &eval);
1938 if (len & KSTRTOX_OVERFLOW)
1939 return -EINVAL;
1940 if (eval != (unsigned long)eval)
1941 return -EINVAL;
1942 str += len;
1943
1944 if (*str != '\0')
1945 return -EINVAL;
1946
1947 *start = sval;
1948 *end = eval;
1949
1950 return 0;
1951}
1952
1953static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
1954{
1955 unsigned long vm_start, vm_end;
1956 bool exact_vma_exists = false;
1957 struct mm_struct *mm = NULL;
1958 struct task_struct *task;
1959 struct inode *inode;
1960 int status = 0;
1961
1962 if (flags & LOOKUP_RCU)
1963 return -ECHILD;
1964
1965 inode = d_inode(dentry);
1966 task = get_proc_task(inode);
1967 if (!task)
1968 goto out_notask;
1969
1970 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
1971 if (IS_ERR_OR_NULL(mm))
1972 goto out;
1973
1974 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
1975 down_read(&mm->mmap_sem);
1976 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
1977 up_read(&mm->mmap_sem);
1978 }
1979
1980 mmput(mm);
1981
1982 if (exact_vma_exists) {
1983 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1984
1985 security_task_to_inode(task, inode);
1986 status = 1;
1987 }
1988
1989out:
1990 put_task_struct(task);
1991
1992out_notask:
1993 return status;
1994}
1995
1996static const struct dentry_operations tid_map_files_dentry_operations = {
1997 .d_revalidate = map_files_d_revalidate,
1998 .d_delete = pid_delete_dentry,
1999};
2000
2001static int map_files_get_link(struct dentry *dentry, struct path *path)
2002{
2003 unsigned long vm_start, vm_end;
2004 struct vm_area_struct *vma;
2005 struct task_struct *task;
2006 struct mm_struct *mm;
2007 int rc;
2008
2009 rc = -ENOENT;
2010 task = get_proc_task(d_inode(dentry));
2011 if (!task)
2012 goto out;
2013
2014 mm = get_task_mm(task);
2015 put_task_struct(task);
2016 if (!mm)
2017 goto out;
2018
2019 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2020 if (rc)
2021 goto out_mmput;
2022
2023 rc = -ENOENT;
2024 down_read(&mm->mmap_sem);
2025 vma = find_exact_vma(mm, vm_start, vm_end);
2026 if (vma && vma->vm_file) {
2027 *path = vma->vm_file->f_path;
2028 path_get(path);
2029 rc = 0;
2030 }
2031 up_read(&mm->mmap_sem);
2032
2033out_mmput:
2034 mmput(mm);
2035out:
2036 return rc;
2037}
2038
2039struct map_files_info {
2040 unsigned long start;
2041 unsigned long end;
2042 fmode_t mode;
2043};
2044
2045/*
2046 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the
2047 * symlinks may be used to bypass permissions on ancestor directories in the
2048 * path to the file in question.
2049 */
2050static const char *
2051proc_map_files_get_link(struct dentry *dentry,
2052 struct inode *inode,
2053 struct delayed_call *done)
2054{
2055 if (!capable(CAP_SYS_ADMIN))
2056 return ERR_PTR(-EPERM);
2057
2058 return proc_pid_get_link(dentry, inode, done);
2059}
2060
2061/*
2062 * Identical to proc_pid_link_inode_operations except for get_link()
2063 */
2064static const struct inode_operations proc_map_files_link_inode_operations = {
2065 .readlink = proc_pid_readlink,
2066 .get_link = proc_map_files_get_link,
2067 .setattr = proc_setattr,
2068};
2069
2070static int
2071proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2072 struct task_struct *task, const void *ptr)
2073{
2074 fmode_t mode = (fmode_t)(unsigned long)ptr;
2075 struct proc_inode *ei;
2076 struct inode *inode;
2077
2078 inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK |
2079 ((mode & FMODE_READ ) ? S_IRUSR : 0) |
2080 ((mode & FMODE_WRITE) ? S_IWUSR : 0));
2081 if (!inode)
2082 return -ENOENT;
2083
2084 ei = PROC_I(inode);
2085 ei->op.proc_get_link = map_files_get_link;
2086
2087 inode->i_op = &proc_map_files_link_inode_operations;
2088 inode->i_size = 64;
2089
2090 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2091 d_add(dentry, inode);
2092
2093 return 0;
2094}
2095
2096static struct dentry *proc_map_files_lookup(struct inode *dir,
2097 struct dentry *dentry, unsigned int flags)
2098{
2099 unsigned long vm_start, vm_end;
2100 struct vm_area_struct *vma;
2101 struct task_struct *task;
2102 int result;
2103 struct mm_struct *mm;
2104
2105 result = -ENOENT;
2106 task = get_proc_task(dir);
2107 if (!task)
2108 goto out;
2109
2110 result = -EACCES;
2111 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2112 goto out_put_task;
2113
2114 result = -ENOENT;
2115 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2116 goto out_put_task;
2117
2118 mm = get_task_mm(task);
2119 if (!mm)
2120 goto out_put_task;
2121
2122 down_read(&mm->mmap_sem);
2123 vma = find_exact_vma(mm, vm_start, vm_end);
2124 if (!vma)
2125 goto out_no_vma;
2126
2127 if (vma->vm_file)
2128 result = proc_map_files_instantiate(dir, dentry, task,
2129 (void *)(unsigned long)vma->vm_file->f_mode);
2130
2131out_no_vma:
2132 up_read(&mm->mmap_sem);
2133 mmput(mm);
2134out_put_task:
2135 put_task_struct(task);
2136out:
2137 return ERR_PTR(result);
2138}
2139
2140static const struct inode_operations proc_map_files_inode_operations = {
2141 .lookup = proc_map_files_lookup,
2142 .permission = proc_fd_permission,
2143 .setattr = proc_setattr,
2144};
2145
2146static int
2147proc_map_files_readdir(struct file *file, struct dir_context *ctx)
2148{
2149 struct vm_area_struct *vma;
2150 struct task_struct *task;
2151 struct mm_struct *mm;
2152 unsigned long nr_files, pos, i;
2153 struct flex_array *fa = NULL;
2154 struct map_files_info info;
2155 struct map_files_info *p;
2156 int ret;
2157
2158 ret = -ENOENT;
2159 task = get_proc_task(file_inode(file));
2160 if (!task)
2161 goto out;
2162
2163 ret = -EACCES;
2164 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2165 goto out_put_task;
2166
2167 ret = 0;
2168 if (!dir_emit_dots(file, ctx))
2169 goto out_put_task;
2170
2171 mm = get_task_mm(task);
2172 if (!mm)
2173 goto out_put_task;
2174 down_read(&mm->mmap_sem);
2175
2176 nr_files = 0;
2177
2178 /*
2179 * We need two passes here:
2180 *
2181 * 1) Collect vmas of mapped files with mmap_sem taken
2182 * 2) Release mmap_sem and instantiate entries
2183 *
2184 * otherwise we get lockdep complained, since filldir()
2185 * routine might require mmap_sem taken in might_fault().
2186 */
2187
2188 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2189 if (vma->vm_file && ++pos > ctx->pos)
2190 nr_files++;
2191 }
2192
2193 if (nr_files) {
2194 fa = flex_array_alloc(sizeof(info), nr_files,
2195 GFP_KERNEL);
2196 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2197 GFP_KERNEL)) {
2198 ret = -ENOMEM;
2199 if (fa)
2200 flex_array_free(fa);
2201 up_read(&mm->mmap_sem);
2202 mmput(mm);
2203 goto out_put_task;
2204 }
2205 for (i = 0, vma = mm->mmap, pos = 2; vma;
2206 vma = vma->vm_next) {
2207 if (!vma->vm_file)
2208 continue;
2209 if (++pos <= ctx->pos)
2210 continue;
2211
2212 info.start = vma->vm_start;
2213 info.end = vma->vm_end;
2214 info.mode = vma->vm_file->f_mode;
2215 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2216 BUG();
2217 }
2218 }
2219 up_read(&mm->mmap_sem);
2220 mmput(mm);
2221
2222 for (i = 0; i < nr_files; i++) {
2223 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */
2224 unsigned int len;
2225
2226 p = flex_array_get(fa, i);
2227 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);
2228 if (!proc_fill_cache(file, ctx,
2229 buf, len,
2230 proc_map_files_instantiate,
2231 task,
2232 (void *)(unsigned long)p->mode))
2233 break;
2234 ctx->pos++;
2235 }
2236 if (fa)
2237 flex_array_free(fa);
2238
2239out_put_task:
2240 put_task_struct(task);
2241out:
2242 return ret;
2243}
2244
2245static const struct file_operations proc_map_files_operations = {
2246 .read = generic_read_dir,
2247 .iterate_shared = proc_map_files_readdir,
2248 .llseek = generic_file_llseek,
2249};
2250
2251#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
2252struct timers_private {
2253 struct pid *pid;
2254 struct task_struct *task;
2255 struct sighand_struct *sighand;
2256 struct pid_namespace *ns;
2257 unsigned long flags;
2258};
2259
2260static void *timers_start(struct seq_file *m, loff_t *pos)
2261{
2262 struct timers_private *tp = m->private;
2263
2264 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2265 if (!tp->task)
2266 return ERR_PTR(-ESRCH);
2267
2268 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2269 if (!tp->sighand)
2270 return ERR_PTR(-ESRCH);
2271
2272 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2273}
2274
2275static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2276{
2277 struct timers_private *tp = m->private;
2278 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2279}
2280
2281static void timers_stop(struct seq_file *m, void *v)
2282{
2283 struct timers_private *tp = m->private;
2284
2285 if (tp->sighand) {
2286 unlock_task_sighand(tp->task, &tp->flags);
2287 tp->sighand = NULL;
2288 }
2289
2290 if (tp->task) {
2291 put_task_struct(tp->task);
2292 tp->task = NULL;
2293 }
2294}
2295
2296static int show_timer(struct seq_file *m, void *v)
2297{
2298 struct k_itimer *timer;
2299 struct timers_private *tp = m->private;
2300 int notify;
2301 static const char * const nstr[] = {
2302 [SIGEV_SIGNAL] = "signal",
2303 [SIGEV_NONE] = "none",
2304 [SIGEV_THREAD] = "thread",
2305 };
2306
2307 timer = list_entry((struct list_head *)v, struct k_itimer, list);
2308 notify = timer->it_sigev_notify;
2309
2310 seq_printf(m, "ID: %d\n", timer->it_id);
2311 seq_printf(m, "signal: %d/%px\n",
2312 timer->sigq->info.si_signo,
2313 timer->sigq->info.si_value.sival_ptr);
2314 seq_printf(m, "notify: %s/%s.%d\n",
2315 nstr[notify & ~SIGEV_THREAD_ID],
2316 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2317 pid_nr_ns(timer->it_pid, tp->ns));
2318 seq_printf(m, "ClockID: %d\n", timer->it_clock);
2319
2320 return 0;
2321}
2322
2323static const struct seq_operations proc_timers_seq_ops = {
2324 .start = timers_start,
2325 .next = timers_next,
2326 .stop = timers_stop,
2327 .show = show_timer,
2328};
2329
2330static int proc_timers_open(struct inode *inode, struct file *file)
2331{
2332 struct timers_private *tp;
2333
2334 tp = __seq_open_private(file, &proc_timers_seq_ops,
2335 sizeof(struct timers_private));
2336 if (!tp)
2337 return -ENOMEM;
2338
2339 tp->pid = proc_pid(inode);
2340 tp->ns = inode->i_sb->s_fs_info;
2341 return 0;
2342}
2343
2344static const struct file_operations proc_timers_operations = {
2345 .open = proc_timers_open,
2346 .read = seq_read,
2347 .llseek = seq_lseek,
2348 .release = seq_release_private,
2349};
2350#endif
2351
2352static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2353 size_t count, loff_t *offset)
2354{
2355 struct inode *inode = file_inode(file);
2356 struct task_struct *p;
2357 u64 slack_ns;
2358 int err;
2359
2360 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2361 if (err < 0)
2362 return err;
2363
2364 p = get_proc_task(inode);
2365 if (!p)
2366 return -ESRCH;
2367
2368 if (p != current) {
2369 if (!capable(CAP_SYS_NICE)) {
2370 count = -EPERM;
2371 goto out;
2372 }
2373
2374 err = security_task_setscheduler(p);
2375 if (err) {
2376 count = err;
2377 goto out;
2378 }
2379 }
2380
2381 task_lock(p);
2382 if (slack_ns == 0)
2383 p->timer_slack_ns = p->default_timer_slack_ns;
2384 else
2385 p->timer_slack_ns = slack_ns;
2386 task_unlock(p);
2387
2388out:
2389 put_task_struct(p);
2390
2391 return count;
2392}
2393
2394static int timerslack_ns_show(struct seq_file *m, void *v)
2395{
2396 struct inode *inode = m->private;
2397 struct task_struct *p;
2398 int err = 0;
2399
2400 p = get_proc_task(inode);
2401 if (!p)
2402 return -ESRCH;
2403
2404 if (p != current) {
2405
2406 if (!capable(CAP_SYS_NICE)) {
2407 err = -EPERM;
2408 goto out;
2409 }
2410 err = security_task_getscheduler(p);
2411 if (err)
2412 goto out;
2413 }
2414
2415 task_lock(p);
2416 seq_printf(m, "%llu\n", p->timer_slack_ns);
2417 task_unlock(p);
2418
2419out:
2420 put_task_struct(p);
2421
2422 return err;
2423}
2424
2425static int timerslack_ns_open(struct inode *inode, struct file *filp)
2426{
2427 return single_open(filp, timerslack_ns_show, inode);
2428}
2429
2430static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2431 .open = timerslack_ns_open,
2432 .read = seq_read,
2433 .write = timerslack_ns_write,
2434 .llseek = seq_lseek,
2435 .release = single_release,
2436};
2437
2438static int proc_pident_instantiate(struct inode *dir,
2439 struct dentry *dentry, struct task_struct *task, const void *ptr)
2440{
2441 const struct pid_entry *p = ptr;
2442 struct inode *inode;
2443 struct proc_inode *ei;
2444
2445 inode = proc_pid_make_inode(dir->i_sb, task, p->mode);
2446 if (!inode)
2447 goto out;
2448
2449 ei = PROC_I(inode);
2450 if (S_ISDIR(inode->i_mode))
2451 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2452 if (p->iop)
2453 inode->i_op = p->iop;
2454 if (p->fop)
2455 inode->i_fop = p->fop;
2456 ei->op = p->op;
2457 d_set_d_op(dentry, &pid_dentry_operations);
2458 d_add(dentry, inode);
2459 /* Close the race of the process dying before we return the dentry */
2460 if (pid_revalidate(dentry, 0))
2461 return 0;
2462out:
2463 return -ENOENT;
2464}
2465
2466static struct dentry *proc_pident_lookup(struct inode *dir,
2467 struct dentry *dentry,
2468 const struct pid_entry *ents,
2469 unsigned int nents)
2470{
2471 int error;
2472 struct task_struct *task = get_proc_task(dir);
2473 const struct pid_entry *p, *last;
2474
2475 error = -ENOENT;
2476
2477 if (!task)
2478 goto out_no_task;
2479
2480 /*
2481 * Yes, it does not scale. And it should not. Don't add
2482 * new entries into /proc/<tgid>/ without very good reasons.
2483 */
2484 last = &ents[nents];
2485 for (p = ents; p < last; p++) {
2486 if (p->len != dentry->d_name.len)
2487 continue;
2488 if (!memcmp(dentry->d_name.name, p->name, p->len))
2489 break;
2490 }
2491 if (p >= last)
2492 goto out;
2493
2494 error = proc_pident_instantiate(dir, dentry, task, p);
2495out:
2496 put_task_struct(task);
2497out_no_task:
2498 return ERR_PTR(error);
2499}
2500
2501static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
2502 const struct pid_entry *ents, unsigned int nents)
2503{
2504 struct task_struct *task = get_proc_task(file_inode(file));
2505 const struct pid_entry *p;
2506
2507 if (!task)
2508 return -ENOENT;
2509
2510 if (!dir_emit_dots(file, ctx))
2511 goto out;
2512
2513 if (ctx->pos >= nents + 2)
2514 goto out;
2515
2516 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
2517 if (!proc_fill_cache(file, ctx, p->name, p->len,
2518 proc_pident_instantiate, task, p))
2519 break;
2520 ctx->pos++;
2521 }
2522out:
2523 put_task_struct(task);
2524 return 0;
2525}
2526
2527#ifdef CONFIG_SECURITY
2528static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2529 size_t count, loff_t *ppos)
2530{
2531 struct inode * inode = file_inode(file);
2532 char *p = NULL;
2533 ssize_t length;
2534 struct task_struct *task = get_proc_task(inode);
2535
2536 if (!task)
2537 return -ESRCH;
2538
2539 length = security_getprocattr(task,
2540 (char*)file->f_path.dentry->d_name.name,
2541 &p);
2542 put_task_struct(task);
2543 if (length > 0)
2544 length = simple_read_from_buffer(buf, count, ppos, p, length);
2545 kfree(p);
2546 return length;
2547}
2548
2549static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2550 size_t count, loff_t *ppos)
2551{
2552 struct inode * inode = file_inode(file);
2553 void *page;
2554 ssize_t length;
2555 struct task_struct *task = get_proc_task(inode);
2556
2557 length = -ESRCH;
2558 if (!task)
2559 goto out_no_task;
2560
2561 /* A task may only write its own attributes. */
2562 length = -EACCES;
2563 if (current != task)
2564 goto out;
2565
2566 if (count > PAGE_SIZE)
2567 count = PAGE_SIZE;
2568
2569 /* No partial writes. */
2570 length = -EINVAL;
2571 if (*ppos != 0)
2572 goto out;
2573
2574 page = memdup_user(buf, count);
2575 if (IS_ERR(page)) {
2576 length = PTR_ERR(page);
2577 goto out;
2578 }
2579
2580 /* Guard against adverse ptrace interaction */
2581 length = mutex_lock_interruptible(¤t->signal->cred_guard_mutex);
2582 if (length < 0)
2583 goto out_free;
2584
2585 length = security_setprocattr(file->f_path.dentry->d_name.name,
2586 page, count);
2587 mutex_unlock(¤t->signal->cred_guard_mutex);
2588out_free:
2589 kfree(page);
2590out:
2591 put_task_struct(task);
2592out_no_task:
2593 return length;
2594}
2595
2596static const struct file_operations proc_pid_attr_operations = {
2597 .read = proc_pid_attr_read,
2598 .write = proc_pid_attr_write,
2599 .llseek = generic_file_llseek,
2600};
2601
2602static const struct pid_entry attr_dir_stuff[] = {
2603 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2604 REG("prev", S_IRUGO, proc_pid_attr_operations),
2605 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2606 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2607 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2608 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2609};
2610
2611static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
2612{
2613 return proc_pident_readdir(file, ctx,
2614 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2615}
2616
2617static const struct file_operations proc_attr_dir_operations = {
2618 .read = generic_read_dir,
2619 .iterate_shared = proc_attr_dir_readdir,
2620 .llseek = generic_file_llseek,
2621};
2622
2623static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2624 struct dentry *dentry, unsigned int flags)
2625{
2626 return proc_pident_lookup(dir, dentry,
2627 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2628}
2629
2630static const struct inode_operations proc_attr_dir_inode_operations = {
2631 .lookup = proc_attr_dir_lookup,
2632 .getattr = pid_getattr,
2633 .setattr = proc_setattr,
2634};
2635
2636#endif
2637
2638#ifdef CONFIG_ELF_CORE
2639static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2640 size_t count, loff_t *ppos)
2641{
2642 struct task_struct *task = get_proc_task(file_inode(file));
2643 struct mm_struct *mm;
2644 char buffer[PROC_NUMBUF];
2645 size_t len;
2646 int ret;
2647
2648 if (!task)
2649 return -ESRCH;
2650
2651 ret = 0;
2652 mm = get_task_mm(task);
2653 if (mm) {
2654 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2655 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2656 MMF_DUMP_FILTER_SHIFT));
2657 mmput(mm);
2658 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2659 }
2660
2661 put_task_struct(task);
2662
2663 return ret;
2664}
2665
2666static ssize_t proc_coredump_filter_write(struct file *file,
2667 const char __user *buf,
2668 size_t count,
2669 loff_t *ppos)
2670{
2671 struct task_struct *task;
2672 struct mm_struct *mm;
2673 unsigned int val;
2674 int ret;
2675 int i;
2676 unsigned long mask;
2677
2678 ret = kstrtouint_from_user(buf, count, 0, &val);
2679 if (ret < 0)
2680 return ret;
2681
2682 ret = -ESRCH;
2683 task = get_proc_task(file_inode(file));
2684 if (!task)
2685 goto out_no_task;
2686
2687 mm = get_task_mm(task);
2688 if (!mm)
2689 goto out_no_mm;
2690 ret = 0;
2691
2692 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2693 if (val & mask)
2694 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2695 else
2696 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2697 }
2698
2699 mmput(mm);
2700 out_no_mm:
2701 put_task_struct(task);
2702 out_no_task:
2703 if (ret < 0)
2704 return ret;
2705 return count;
2706}
2707
2708static const struct file_operations proc_coredump_filter_operations = {
2709 .read = proc_coredump_filter_read,
2710 .write = proc_coredump_filter_write,
2711 .llseek = generic_file_llseek,
2712};
2713#endif
2714
2715#ifdef CONFIG_TASK_IO_ACCOUNTING
2716static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
2717{
2718 struct task_io_accounting acct = task->ioac;
2719 unsigned long flags;
2720 int result;
2721
2722 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2723 if (result)
2724 return result;
2725
2726 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
2727 result = -EACCES;
2728 goto out_unlock;
2729 }
2730
2731 if (whole && lock_task_sighand(task, &flags)) {
2732 struct task_struct *t = task;
2733
2734 task_io_accounting_add(&acct, &task->signal->ioac);
2735 while_each_thread(task, t)
2736 task_io_accounting_add(&acct, &t->ioac);
2737
2738 unlock_task_sighand(task, &flags);
2739 }
2740 seq_printf(m,
2741 "rchar: %llu\n"
2742 "wchar: %llu\n"
2743 "syscr: %llu\n"
2744 "syscw: %llu\n"
2745 "read_bytes: %llu\n"
2746 "write_bytes: %llu\n"
2747 "cancelled_write_bytes: %llu\n",
2748 (unsigned long long)acct.rchar,
2749 (unsigned long long)acct.wchar,
2750 (unsigned long long)acct.syscr,
2751 (unsigned long long)acct.syscw,
2752 (unsigned long long)acct.read_bytes,
2753 (unsigned long long)acct.write_bytes,
2754 (unsigned long long)acct.cancelled_write_bytes);
2755 result = 0;
2756
2757out_unlock:
2758 mutex_unlock(&task->signal->cred_guard_mutex);
2759 return result;
2760}
2761
2762static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2763 struct pid *pid, struct task_struct *task)
2764{
2765 return do_io_accounting(task, m, 0);
2766}
2767
2768static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2769 struct pid *pid, struct task_struct *task)
2770{
2771 return do_io_accounting(task, m, 1);
2772}
2773#endif /* CONFIG_TASK_IO_ACCOUNTING */
2774
2775#ifdef CONFIG_USER_NS
2776static int proc_id_map_open(struct inode *inode, struct file *file,
2777 const struct seq_operations *seq_ops)
2778{
2779 struct user_namespace *ns = NULL;
2780 struct task_struct *task;
2781 struct seq_file *seq;
2782 int ret = -EINVAL;
2783
2784 task = get_proc_task(inode);
2785 if (task) {
2786 rcu_read_lock();
2787 ns = get_user_ns(task_cred_xxx(task, user_ns));
2788 rcu_read_unlock();
2789 put_task_struct(task);
2790 }
2791 if (!ns)
2792 goto err;
2793
2794 ret = seq_open(file, seq_ops);
2795 if (ret)
2796 goto err_put_ns;
2797
2798 seq = file->private_data;
2799 seq->private = ns;
2800
2801 return 0;
2802err_put_ns:
2803 put_user_ns(ns);
2804err:
2805 return ret;
2806}
2807
2808static int proc_id_map_release(struct inode *inode, struct file *file)
2809{
2810 struct seq_file *seq = file->private_data;
2811 struct user_namespace *ns = seq->private;
2812 put_user_ns(ns);
2813 return seq_release(inode, file);
2814}
2815
2816static int proc_uid_map_open(struct inode *inode, struct file *file)
2817{
2818 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2819}
2820
2821static int proc_gid_map_open(struct inode *inode, struct file *file)
2822{
2823 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2824}
2825
2826static int proc_projid_map_open(struct inode *inode, struct file *file)
2827{
2828 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
2829}
2830
2831static const struct file_operations proc_uid_map_operations = {
2832 .open = proc_uid_map_open,
2833 .write = proc_uid_map_write,
2834 .read = seq_read,
2835 .llseek = seq_lseek,
2836 .release = proc_id_map_release,
2837};
2838
2839static const struct file_operations proc_gid_map_operations = {
2840 .open = proc_gid_map_open,
2841 .write = proc_gid_map_write,
2842 .read = seq_read,
2843 .llseek = seq_lseek,
2844 .release = proc_id_map_release,
2845};
2846
2847static const struct file_operations proc_projid_map_operations = {
2848 .open = proc_projid_map_open,
2849 .write = proc_projid_map_write,
2850 .read = seq_read,
2851 .llseek = seq_lseek,
2852 .release = proc_id_map_release,
2853};
2854
2855static int proc_setgroups_open(struct inode *inode, struct file *file)
2856{
2857 struct user_namespace *ns = NULL;
2858 struct task_struct *task;
2859 int ret;
2860
2861 ret = -ESRCH;
2862 task = get_proc_task(inode);
2863 if (task) {
2864 rcu_read_lock();
2865 ns = get_user_ns(task_cred_xxx(task, user_ns));
2866 rcu_read_unlock();
2867 put_task_struct(task);
2868 }
2869 if (!ns)
2870 goto err;
2871
2872 if (file->f_mode & FMODE_WRITE) {
2873 ret = -EACCES;
2874 if (!ns_capable(ns, CAP_SYS_ADMIN))
2875 goto err_put_ns;
2876 }
2877
2878 ret = single_open(file, &proc_setgroups_show, ns);
2879 if (ret)
2880 goto err_put_ns;
2881
2882 return 0;
2883err_put_ns:
2884 put_user_ns(ns);
2885err:
2886 return ret;
2887}
2888
2889static int proc_setgroups_release(struct inode *inode, struct file *file)
2890{
2891 struct seq_file *seq = file->private_data;
2892 struct user_namespace *ns = seq->private;
2893 int ret = single_release(inode, file);
2894 put_user_ns(ns);
2895 return ret;
2896}
2897
2898static const struct file_operations proc_setgroups_operations = {
2899 .open = proc_setgroups_open,
2900 .write = proc_setgroups_write,
2901 .read = seq_read,
2902 .llseek = seq_lseek,
2903 .release = proc_setgroups_release,
2904};
2905#endif /* CONFIG_USER_NS */
2906
2907static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2908 struct pid *pid, struct task_struct *task)
2909{
2910 int err = lock_trace(task);
2911 if (!err) {
2912 seq_printf(m, "%08x\n", task->personality);
2913 unlock_trace(task);
2914 }
2915 return err;
2916}
2917
2918#ifdef CONFIG_LIVEPATCH
2919static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns,
2920 struct pid *pid, struct task_struct *task)
2921{
2922 seq_printf(m, "%d\n", task->patch_state);
2923 return 0;
2924}
2925#endif /* CONFIG_LIVEPATCH */
2926
2927/*
2928 * Thread groups
2929 */
2930static const struct file_operations proc_task_operations;
2931static const struct inode_operations proc_task_inode_operations;
2932
2933static const struct pid_entry tgid_base_stuff[] = {
2934 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2935 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2936 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
2937 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2938 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
2939#ifdef CONFIG_NET
2940 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
2941#endif
2942 REG("environ", S_IRUSR, proc_environ_operations),
2943 REG("auxv", S_IRUSR, proc_auxv_operations),
2944 ONE("status", S_IRUGO, proc_pid_status),
2945 ONE("personality", S_IRUSR, proc_pid_personality),
2946 ONE("limits", S_IRUGO, proc_pid_limits),
2947#ifdef CONFIG_SCHED_DEBUG
2948 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2949#endif
2950#ifdef CONFIG_SCHED_AUTOGROUP
2951 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
2952#endif
2953 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2954#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2955 ONE("syscall", S_IRUSR, proc_pid_syscall),
2956#endif
2957 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
2958 ONE("stat", S_IRUGO, proc_tgid_stat),
2959 ONE("statm", S_IRUGO, proc_pid_statm),
2960 REG("maps", S_IRUGO, proc_pid_maps_operations),
2961#ifdef CONFIG_NUMA
2962 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
2963#endif
2964 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2965 LNK("cwd", proc_cwd_link),
2966 LNK("root", proc_root_link),
2967 LNK("exe", proc_exe_link),
2968 REG("mounts", S_IRUGO, proc_mounts_operations),
2969 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2970 REG("mountstats", S_IRUSR, proc_mountstats_operations),
2971#ifdef CONFIG_PROC_PAGE_MONITOR
2972 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2973 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
2974 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
2975 REG("pagemap", S_IRUSR, proc_pagemap_operations),
2976#endif
2977#ifdef CONFIG_SECURITY
2978 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
2979#endif
2980#ifdef CONFIG_KALLSYMS
2981 ONE("wchan", S_IRUGO, proc_pid_wchan),
2982#endif
2983#ifdef CONFIG_STACKTRACE
2984 ONE("stack", S_IRUSR, proc_pid_stack),
2985#endif
2986#ifdef CONFIG_SCHED_INFO
2987 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
2988#endif
2989#ifdef CONFIG_LATENCYTOP
2990 REG("latency", S_IRUGO, proc_lstats_operations),
2991#endif
2992#ifdef CONFIG_PROC_PID_CPUSET
2993 ONE("cpuset", S_IRUGO, proc_cpuset_show),
2994#endif
2995#ifdef CONFIG_CGROUPS
2996 ONE("cgroup", S_IRUGO, proc_cgroup_show),
2997#endif
2998 ONE("oom_score", S_IRUGO, proc_oom_score),
2999 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3000 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3001#ifdef CONFIG_AUDITSYSCALL
3002 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3003 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3004#endif
3005#ifdef CONFIG_FAULT_INJECTION
3006 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3007 REG("fail-nth", 0644, proc_fail_nth_operations),
3008#endif
3009#ifdef CONFIG_ELF_CORE
3010 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3011#endif
3012#ifdef CONFIG_TASK_IO_ACCOUNTING
3013 ONE("io", S_IRUSR, proc_tgid_io_accounting),
3014#endif
3015#ifdef CONFIG_USER_NS
3016 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3017 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3018 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3019 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3020#endif
3021#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
3022 REG("timers", S_IRUGO, proc_timers_operations),
3023#endif
3024 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
3025#ifdef CONFIG_LIVEPATCH
3026 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3027#endif
3028};
3029
3030static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
3031{
3032 return proc_pident_readdir(file, ctx,
3033 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3034}
3035
3036static const struct file_operations proc_tgid_base_operations = {
3037 .read = generic_read_dir,
3038 .iterate_shared = proc_tgid_base_readdir,
3039 .llseek = generic_file_llseek,
3040};
3041
3042static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3043{
3044 return proc_pident_lookup(dir, dentry,
3045 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3046}
3047
3048static const struct inode_operations proc_tgid_base_inode_operations = {
3049 .lookup = proc_tgid_base_lookup,
3050 .getattr = pid_getattr,
3051 .setattr = proc_setattr,
3052 .permission = proc_pid_permission,
3053};
3054
3055static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
3056{
3057 struct dentry *dentry, *leader, *dir;
3058 char buf[10 + 1];
3059 struct qstr name;
3060
3061 name.name = buf;
3062 name.len = snprintf(buf, sizeof(buf), "%u", pid);
3063 /* no ->d_hash() rejects on procfs */
3064 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
3065 if (dentry) {
3066 d_invalidate(dentry);
3067 dput(dentry);
3068 }
3069
3070 if (pid == tgid)
3071 return;
3072
3073 name.name = buf;
3074 name.len = snprintf(buf, sizeof(buf), "%u", tgid);
3075 leader = d_hash_and_lookup(mnt->mnt_root, &name);
3076 if (!leader)
3077 goto out;
3078
3079 name.name = "task";
3080 name.len = strlen(name.name);
3081 dir = d_hash_and_lookup(leader, &name);
3082 if (!dir)
3083 goto out_put_leader;
3084
3085 name.name = buf;
3086 name.len = snprintf(buf, sizeof(buf), "%u", pid);
3087 dentry = d_hash_and_lookup(dir, &name);
3088 if (dentry) {
3089 d_invalidate(dentry);
3090 dput(dentry);
3091 }
3092
3093 dput(dir);
3094out_put_leader:
3095 dput(leader);
3096out:
3097 return;
3098}
3099
3100/**
3101 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3102 * @task: task that should be flushed.
3103 *
3104 * When flushing dentries from proc, one needs to flush them from global
3105 * proc (proc_mnt) and from all the namespaces' procs this task was seen
3106 * in. This call is supposed to do all of this job.
3107 *
3108 * Looks in the dcache for
3109 * /proc/@pid
3110 * /proc/@tgid/task/@pid
3111 * if either directory is present flushes it and all of it'ts children
3112 * from the dcache.
3113 *
3114 * It is safe and reasonable to cache /proc entries for a task until
3115 * that task exits. After that they just clog up the dcache with
3116 * useless entries, possibly causing useful dcache entries to be
3117 * flushed instead. This routine is proved to flush those useless
3118 * dcache entries at process exit time.
3119 *
3120 * NOTE: This routine is just an optimization so it does not guarantee
3121 * that no dcache entries will exist at process exit time it
3122 * just makes it very unlikely that any will persist.
3123 */
3124
3125void proc_flush_task(struct task_struct *task)
3126{
3127 int i;
3128 struct pid *pid, *tgid;
3129 struct upid *upid;
3130
3131 pid = task_pid(task);
3132 tgid = task_tgid(task);
3133
3134 for (i = 0; i <= pid->level; i++) {
3135 upid = &pid->numbers[i];
3136 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
3137 tgid->numbers[i].nr);
3138 }
3139}
3140
3141static int proc_pid_instantiate(struct inode *dir,
3142 struct dentry * dentry,
3143 struct task_struct *task, const void *ptr)
3144{
3145 struct inode *inode;
3146
3147 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
3148 if (!inode)
3149 goto out;
3150
3151 inode->i_op = &proc_tgid_base_inode_operations;
3152 inode->i_fop = &proc_tgid_base_operations;
3153 inode->i_flags|=S_IMMUTABLE;
3154
3155 set_nlink(inode, nlink_tgid);
3156
3157 d_set_d_op(dentry, &pid_dentry_operations);
3158
3159 d_add(dentry, inode);
3160 /* Close the race of the process dying before we return the dentry */
3161 if (pid_revalidate(dentry, 0))
3162 return 0;
3163out:
3164 return -ENOENT;
3165}
3166
3167struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3168{
3169 int result = -ENOENT;
3170 struct task_struct *task;
3171 unsigned tgid;
3172 struct pid_namespace *ns;
3173
3174 tgid = name_to_int(&dentry->d_name);
3175 if (tgid == ~0U)
3176 goto out;
3177
3178 ns = dentry->d_sb->s_fs_info;
3179 rcu_read_lock();
3180 task = find_task_by_pid_ns(tgid, ns);
3181 if (task)
3182 get_task_struct(task);
3183 rcu_read_unlock();
3184 if (!task)
3185 goto out;
3186
3187 result = proc_pid_instantiate(dir, dentry, task, NULL);
3188 put_task_struct(task);
3189out:
3190 return ERR_PTR(result);
3191}
3192
3193/*
3194 * Find the first task with tgid >= tgid
3195 *
3196 */
3197struct tgid_iter {
3198 unsigned int tgid;
3199 struct task_struct *task;
3200};
3201static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3202{
3203 struct pid *pid;
3204
3205 if (iter.task)
3206 put_task_struct(iter.task);
3207 rcu_read_lock();
3208retry:
3209 iter.task = NULL;
3210 pid = find_ge_pid(iter.tgid, ns);
3211 if (pid) {
3212 iter.tgid = pid_nr_ns(pid, ns);
3213 iter.task = pid_task(pid, PIDTYPE_PID);
3214 /* What we to know is if the pid we have find is the
3215 * pid of a thread_group_leader. Testing for task
3216 * being a thread_group_leader is the obvious thing
3217 * todo but there is a window when it fails, due to
3218 * the pid transfer logic in de_thread.
3219 *
3220 * So we perform the straight forward test of seeing
3221 * if the pid we have found is the pid of a thread
3222 * group leader, and don't worry if the task we have
3223 * found doesn't happen to be a thread group leader.
3224 * As we don't care in the case of readdir.
3225 */
3226 if (!iter.task || !has_group_leader_pid(iter.task)) {
3227 iter.tgid += 1;
3228 goto retry;
3229 }
3230 get_task_struct(iter.task);
3231 }
3232 rcu_read_unlock();
3233 return iter;
3234}
3235
3236#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
3237
3238/* for the /proc/ directory itself, after non-process stuff has been done */
3239int proc_pid_readdir(struct file *file, struct dir_context *ctx)
3240{
3241 struct tgid_iter iter;
3242 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info;
3243 loff_t pos = ctx->pos;
3244
3245 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
3246 return 0;
3247
3248 if (pos == TGID_OFFSET - 2) {
3249 struct inode *inode = d_inode(ns->proc_self);
3250 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
3251 return 0;
3252 ctx->pos = pos = pos + 1;
3253 }
3254 if (pos == TGID_OFFSET - 1) {
3255 struct inode *inode = d_inode(ns->proc_thread_self);
3256 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3257 return 0;
3258 ctx->pos = pos = pos + 1;
3259 }
3260 iter.tgid = pos - TGID_OFFSET;
3261 iter.task = NULL;
3262 for (iter = next_tgid(ns, iter);
3263 iter.task;
3264 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3265 char name[10 + 1];
3266 int len;
3267
3268 cond_resched();
3269 if (!has_pid_permissions(ns, iter.task, HIDEPID_INVISIBLE))
3270 continue;
3271
3272 len = snprintf(name, sizeof(name), "%u", iter.tgid);
3273 ctx->pos = iter.tgid + TGID_OFFSET;
3274 if (!proc_fill_cache(file, ctx, name, len,
3275 proc_pid_instantiate, iter.task, NULL)) {
3276 put_task_struct(iter.task);
3277 return 0;
3278 }
3279 }
3280 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
3281 return 0;
3282}
3283
3284/*
3285 * proc_tid_comm_permission is a special permission function exclusively
3286 * used for the node /proc/<pid>/task/<tid>/comm.
3287 * It bypasses generic permission checks in the case where a task of the same
3288 * task group attempts to access the node.
3289 * The rationale behind this is that glibc and bionic access this node for
3290 * cross thread naming (pthread_set/getname_np(!self)). However, if
3291 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3292 * which locks out the cross thread naming implementation.
3293 * This function makes sure that the node is always accessible for members of
3294 * same thread group.
3295 */
3296static int proc_tid_comm_permission(struct inode *inode, int mask)
3297{
3298 bool is_same_tgroup;
3299 struct task_struct *task;
3300
3301 task = get_proc_task(inode);
3302 if (!task)
3303 return -ESRCH;
3304 is_same_tgroup = same_thread_group(current, task);
3305 put_task_struct(task);
3306
3307 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3308 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3309 * read or written by the members of the corresponding
3310 * thread group.
3311 */
3312 return 0;
3313 }
3314
3315 return generic_permission(inode, mask);
3316}
3317
3318static const struct inode_operations proc_tid_comm_inode_operations = {
3319 .permission = proc_tid_comm_permission,
3320};
3321
3322/*
3323 * Tasks
3324 */
3325static const struct pid_entry tid_base_stuff[] = {
3326 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3327 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3328 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3329#ifdef CONFIG_NET
3330 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3331#endif
3332 REG("environ", S_IRUSR, proc_environ_operations),
3333 REG("auxv", S_IRUSR, proc_auxv_operations),
3334 ONE("status", S_IRUGO, proc_pid_status),
3335 ONE("personality", S_IRUSR, proc_pid_personality),
3336 ONE("limits", S_IRUGO, proc_pid_limits),
3337#ifdef CONFIG_SCHED_DEBUG
3338 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3339#endif
3340 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3341 &proc_tid_comm_inode_operations,
3342 &proc_pid_set_comm_operations, {}),
3343#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3344 ONE("syscall", S_IRUSR, proc_pid_syscall),
3345#endif
3346 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3347 ONE("stat", S_IRUGO, proc_tid_stat),
3348 ONE("statm", S_IRUGO, proc_pid_statm),
3349 REG("maps", S_IRUGO, proc_tid_maps_operations),
3350#ifdef CONFIG_PROC_CHILDREN
3351 REG("children", S_IRUGO, proc_tid_children_operations),
3352#endif
3353#ifdef CONFIG_NUMA
3354 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
3355#endif
3356 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3357 LNK("cwd", proc_cwd_link),
3358 LNK("root", proc_root_link),
3359 LNK("exe", proc_exe_link),
3360 REG("mounts", S_IRUGO, proc_mounts_operations),
3361 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3362#ifdef CONFIG_PROC_PAGE_MONITOR
3363 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3364 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
3365 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3366 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3367#endif
3368#ifdef CONFIG_SECURITY
3369 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3370#endif
3371#ifdef CONFIG_KALLSYMS
3372 ONE("wchan", S_IRUGO, proc_pid_wchan),
3373#endif
3374#ifdef CONFIG_STACKTRACE
3375 ONE("stack", S_IRUSR, proc_pid_stack),
3376#endif
3377#ifdef CONFIG_SCHED_INFO
3378 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3379#endif
3380#ifdef CONFIG_LATENCYTOP
3381 REG("latency", S_IRUGO, proc_lstats_operations),
3382#endif
3383#ifdef CONFIG_PROC_PID_CPUSET
3384 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3385#endif
3386#ifdef CONFIG_CGROUPS
3387 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3388#endif
3389 ONE("oom_score", S_IRUGO, proc_oom_score),
3390 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3391 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3392#ifdef CONFIG_AUDITSYSCALL
3393 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3394 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3395#endif
3396#ifdef CONFIG_FAULT_INJECTION
3397 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3398 REG("fail-nth", 0644, proc_fail_nth_operations),
3399#endif
3400#ifdef CONFIG_TASK_IO_ACCOUNTING
3401 ONE("io", S_IRUSR, proc_tid_io_accounting),
3402#endif
3403#ifdef CONFIG_USER_NS
3404 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3405 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3406 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3407 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3408#endif
3409#ifdef CONFIG_LIVEPATCH
3410 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3411#endif
3412};
3413
3414static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
3415{
3416 return proc_pident_readdir(file, ctx,
3417 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3418}
3419
3420static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3421{
3422 return proc_pident_lookup(dir, dentry,
3423 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3424}
3425
3426static const struct file_operations proc_tid_base_operations = {
3427 .read = generic_read_dir,
3428 .iterate_shared = proc_tid_base_readdir,
3429 .llseek = generic_file_llseek,
3430};
3431
3432static const struct inode_operations proc_tid_base_inode_operations = {
3433 .lookup = proc_tid_base_lookup,
3434 .getattr = pid_getattr,
3435 .setattr = proc_setattr,
3436};
3437
3438static int proc_task_instantiate(struct inode *dir,
3439 struct dentry *dentry, struct task_struct *task, const void *ptr)
3440{
3441 struct inode *inode;
3442 inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
3443
3444 if (!inode)
3445 goto out;
3446 inode->i_op = &proc_tid_base_inode_operations;
3447 inode->i_fop = &proc_tid_base_operations;
3448 inode->i_flags|=S_IMMUTABLE;
3449
3450 set_nlink(inode, nlink_tid);
3451
3452 d_set_d_op(dentry, &pid_dentry_operations);
3453
3454 d_add(dentry, inode);
3455 /* Close the race of the process dying before we return the dentry */
3456 if (pid_revalidate(dentry, 0))
3457 return 0;
3458out:
3459 return -ENOENT;
3460}
3461
3462static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3463{
3464 int result = -ENOENT;
3465 struct task_struct *task;
3466 struct task_struct *leader = get_proc_task(dir);
3467 unsigned tid;
3468 struct pid_namespace *ns;
3469
3470 if (!leader)
3471 goto out_no_task;
3472
3473 tid = name_to_int(&dentry->d_name);
3474 if (tid == ~0U)
3475 goto out;
3476
3477 ns = dentry->d_sb->s_fs_info;
3478 rcu_read_lock();
3479 task = find_task_by_pid_ns(tid, ns);
3480 if (task)
3481 get_task_struct(task);
3482 rcu_read_unlock();
3483 if (!task)
3484 goto out;
3485 if (!same_thread_group(leader, task))
3486 goto out_drop_task;
3487
3488 result = proc_task_instantiate(dir, dentry, task, NULL);
3489out_drop_task:
3490 put_task_struct(task);
3491out:
3492 put_task_struct(leader);
3493out_no_task:
3494 return ERR_PTR(result);
3495}
3496
3497/*
3498 * Find the first tid of a thread group to return to user space.
3499 *
3500 * Usually this is just the thread group leader, but if the users
3501 * buffer was too small or there was a seek into the middle of the
3502 * directory we have more work todo.
3503 *
3504 * In the case of a short read we start with find_task_by_pid.
3505 *
3506 * In the case of a seek we start with the leader and walk nr
3507 * threads past it.
3508 */
3509static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3510 struct pid_namespace *ns)
3511{
3512 struct task_struct *pos, *task;
3513 unsigned long nr = f_pos;
3514
3515 if (nr != f_pos) /* 32bit overflow? */
3516 return NULL;
3517
3518 rcu_read_lock();
3519 task = pid_task(pid, PIDTYPE_PID);
3520 if (!task)
3521 goto fail;
3522
3523 /* Attempt to start with the tid of a thread */
3524 if (tid && nr) {
3525 pos = find_task_by_pid_ns(tid, ns);
3526 if (pos && same_thread_group(pos, task))
3527 goto found;
3528 }
3529
3530 /* If nr exceeds the number of threads there is nothing todo */
3531 if (nr >= get_nr_threads(task))
3532 goto fail;
3533
3534 /* If we haven't found our starting place yet start
3535 * with the leader and walk nr threads forward.
3536 */
3537 pos = task = task->group_leader;
3538 do {
3539 if (!nr--)
3540 goto found;
3541 } while_each_thread(task, pos);
3542fail:
3543 pos = NULL;
3544 goto out;
3545found:
3546 get_task_struct(pos);
3547out:
3548 rcu_read_unlock();
3549 return pos;
3550}
3551
3552/*
3553 * Find the next thread in the thread list.
3554 * Return NULL if there is an error or no next thread.
3555 *
3556 * The reference to the input task_struct is released.
3557 */
3558static struct task_struct *next_tid(struct task_struct *start)
3559{
3560 struct task_struct *pos = NULL;
3561 rcu_read_lock();
3562 if (pid_alive(start)) {
3563 pos = next_thread(start);
3564 if (thread_group_leader(pos))
3565 pos = NULL;
3566 else
3567 get_task_struct(pos);
3568 }
3569 rcu_read_unlock();
3570 put_task_struct(start);
3571 return pos;
3572}
3573
3574/* for the /proc/TGID/task/ directories */
3575static int proc_task_readdir(struct file *file, struct dir_context *ctx)
3576{
3577 struct inode *inode = file_inode(file);
3578 struct task_struct *task;
3579 struct pid_namespace *ns;
3580 int tid;
3581
3582 if (proc_inode_is_dead(inode))
3583 return -ENOENT;
3584
3585 if (!dir_emit_dots(file, ctx))
3586 return 0;
3587
3588 /* f_version caches the tgid value that the last readdir call couldn't
3589 * return. lseek aka telldir automagically resets f_version to 0.
3590 */
3591 ns = inode->i_sb->s_fs_info;
3592 tid = (int)file->f_version;
3593 file->f_version = 0;
3594 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
3595 task;
3596 task = next_tid(task), ctx->pos++) {
3597 char name[10 + 1];
3598 int len;
3599 tid = task_pid_nr_ns(task, ns);
3600 len = snprintf(name, sizeof(name), "%u", tid);
3601 if (!proc_fill_cache(file, ctx, name, len,
3602 proc_task_instantiate, task, NULL)) {
3603 /* returning this tgid failed, save it as the first
3604 * pid for the next readir call */
3605 file->f_version = (u64)tid;
3606 put_task_struct(task);
3607 break;
3608 }
3609 }
3610
3611 return 0;
3612}
3613
3614static int proc_task_getattr(const struct path *path, struct kstat *stat,
3615 u32 request_mask, unsigned int query_flags)
3616{
3617 struct inode *inode = d_inode(path->dentry);
3618 struct task_struct *p = get_proc_task(inode);
3619 generic_fillattr(inode, stat);
3620
3621 if (p) {
3622 stat->nlink += get_nr_threads(p);
3623 put_task_struct(p);
3624 }
3625
3626 return 0;
3627}
3628
3629static const struct inode_operations proc_task_inode_operations = {
3630 .lookup = proc_task_lookup,
3631 .getattr = proc_task_getattr,
3632 .setattr = proc_setattr,
3633 .permission = proc_pid_permission,
3634};
3635
3636static const struct file_operations proc_task_operations = {
3637 .read = generic_read_dir,
3638 .iterate_shared = proc_task_readdir,
3639 .llseek = generic_file_llseek,
3640};
3641
3642void __init set_proc_pid_nlink(void)
3643{
3644 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3645 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3646}