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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/proc/base.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 *
7 * proc base directory handling functions
8 *
9 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
10 * Instead of using magical inumbers to determine the kind of object
11 * we allocate and fill in-core inodes upon lookup. They don't even
12 * go into icache. We cache the reference to task_struct upon lookup too.
13 * Eventually it should become a filesystem in its own. We don't use the
14 * rest of procfs anymore.
15 *
16 *
17 * Changelog:
18 * 17-Jan-2005
19 * Allan Bezerra
20 * Bruna Moreira <bruna.moreira@indt.org.br>
21 * Edjard Mota <edjard.mota@indt.org.br>
22 * Ilias Biris <ilias.biris@indt.org.br>
23 * Mauricio Lin <mauricio.lin@indt.org.br>
24 *
25 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
26 *
27 * A new process specific entry (smaps) included in /proc. It shows the
28 * size of rss for each memory area. The maps entry lacks information
29 * about physical memory size (rss) for each mapped file, i.e.,
30 * rss information for executables and library files.
31 * This additional information is useful for any tools that need to know
32 * about physical memory consumption for a process specific library.
33 *
34 * Changelog:
35 * 21-Feb-2005
36 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
37 * Pud inclusion in the page table walking.
38 *
39 * ChangeLog:
40 * 10-Mar-2005
41 * 10LE Instituto Nokia de Tecnologia - INdT:
42 * A better way to walks through the page table as suggested by Hugh Dickins.
43 *
44 * Simo Piiroinen <simo.piiroinen@nokia.com>:
45 * Smaps information related to shared, private, clean and dirty pages.
46 *
47 * Paul Mundt <paul.mundt@nokia.com>:
48 * Overall revision about smaps.
49 */
50
51#include <linux/uaccess.h>
52
53#include <linux/errno.h>
54#include <linux/time.h>
55#include <linux/proc_fs.h>
56#include <linux/stat.h>
57#include <linux/task_io_accounting_ops.h>
58#include <linux/init.h>
59#include <linux/capability.h>
60#include <linux/file.h>
61#include <linux/fdtable.h>
62#include <linux/generic-radix-tree.h>
63#include <linux/string.h>
64#include <linux/seq_file.h>
65#include <linux/namei.h>
66#include <linux/mnt_namespace.h>
67#include <linux/mm.h>
68#include <linux/swap.h>
69#include <linux/rcupdate.h>
70#include <linux/kallsyms.h>
71#include <linux/stacktrace.h>
72#include <linux/resource.h>
73#include <linux/module.h>
74#include <linux/mount.h>
75#include <linux/security.h>
76#include <linux/ptrace.h>
77#include <linux/printk.h>
78#include <linux/cache.h>
79#include <linux/cgroup.h>
80#include <linux/cpuset.h>
81#include <linux/audit.h>
82#include <linux/poll.h>
83#include <linux/nsproxy.h>
84#include <linux/oom.h>
85#include <linux/elf.h>
86#include <linux/pid_namespace.h>
87#include <linux/user_namespace.h>
88#include <linux/fs_struct.h>
89#include <linux/slab.h>
90#include <linux/sched/autogroup.h>
91#include <linux/sched/mm.h>
92#include <linux/sched/coredump.h>
93#include <linux/sched/debug.h>
94#include <linux/sched/stat.h>
95#include <linux/posix-timers.h>
96#include <linux/time_namespace.h>
97#include <linux/resctrl.h>
98#include <linux/cn_proc.h>
99#include <trace/events/oom.h>
100#include "internal.h"
101#include "fd.h"
102
103#include "../../lib/kstrtox.h"
104
105/* NOTE:
106 * Implementing inode permission operations in /proc is almost
107 * certainly an error. Permission checks need to happen during
108 * each system call not at open time. The reason is that most of
109 * what we wish to check for permissions in /proc varies at runtime.
110 *
111 * The classic example of a problem is opening file descriptors
112 * in /proc for a task before it execs a suid executable.
113 */
114
115static u8 nlink_tid __ro_after_init;
116static u8 nlink_tgid __ro_after_init;
117
118struct pid_entry {
119 const char *name;
120 unsigned int len;
121 umode_t mode;
122 const struct inode_operations *iop;
123 const struct file_operations *fop;
124 union proc_op op;
125};
126
127#define NOD(NAME, MODE, IOP, FOP, OP) { \
128 .name = (NAME), \
129 .len = sizeof(NAME) - 1, \
130 .mode = MODE, \
131 .iop = IOP, \
132 .fop = FOP, \
133 .op = OP, \
134}
135
136#define DIR(NAME, MODE, iops, fops) \
137 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
138#define LNK(NAME, get_link) \
139 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
140 &proc_pid_link_inode_operations, NULL, \
141 { .proc_get_link = get_link } )
142#define REG(NAME, MODE, fops) \
143 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
144#define ONE(NAME, MODE, show) \
145 NOD(NAME, (S_IFREG|(MODE)), \
146 NULL, &proc_single_file_operations, \
147 { .proc_show = show } )
148#define ATTR(LSM, NAME, MODE) \
149 NOD(NAME, (S_IFREG|(MODE)), \
150 NULL, &proc_pid_attr_operations, \
151 { .lsm = LSM })
152
153/*
154 * Count the number of hardlinks for the pid_entry table, excluding the .
155 * and .. links.
156 */
157static unsigned int __init pid_entry_nlink(const struct pid_entry *entries,
158 unsigned int n)
159{
160 unsigned int i;
161 unsigned int count;
162
163 count = 2;
164 for (i = 0; i < n; ++i) {
165 if (S_ISDIR(entries[i].mode))
166 ++count;
167 }
168
169 return count;
170}
171
172static int get_task_root(struct task_struct *task, struct path *root)
173{
174 int result = -ENOENT;
175
176 task_lock(task);
177 if (task->fs) {
178 get_fs_root(task->fs, root);
179 result = 0;
180 }
181 task_unlock(task);
182 return result;
183}
184
185static int proc_cwd_link(struct dentry *dentry, struct path *path)
186{
187 struct task_struct *task = get_proc_task(d_inode(dentry));
188 int result = -ENOENT;
189
190 if (task) {
191 task_lock(task);
192 if (task->fs) {
193 get_fs_pwd(task->fs, path);
194 result = 0;
195 }
196 task_unlock(task);
197 put_task_struct(task);
198 }
199 return result;
200}
201
202static int proc_root_link(struct dentry *dentry, struct path *path)
203{
204 struct task_struct *task = get_proc_task(d_inode(dentry));
205 int result = -ENOENT;
206
207 if (task) {
208 result = get_task_root(task, path);
209 put_task_struct(task);
210 }
211 return result;
212}
213
214/*
215 * If the user used setproctitle(), we just get the string from
216 * user space at arg_start, and limit it to a maximum of one page.
217 */
218static ssize_t get_mm_proctitle(struct mm_struct *mm, char __user *buf,
219 size_t count, unsigned long pos,
220 unsigned long arg_start)
221{
222 char *page;
223 int ret, got;
224
225 if (pos >= PAGE_SIZE)
226 return 0;
227
228 page = (char *)__get_free_page(GFP_KERNEL);
229 if (!page)
230 return -ENOMEM;
231
232 ret = 0;
233 got = access_remote_vm(mm, arg_start, page, PAGE_SIZE, FOLL_ANON);
234 if (got > 0) {
235 int len = strnlen(page, got);
236
237 /* Include the NUL character if it was found */
238 if (len < got)
239 len++;
240
241 if (len > pos) {
242 len -= pos;
243 if (len > count)
244 len = count;
245 len -= copy_to_user(buf, page+pos, len);
246 if (!len)
247 len = -EFAULT;
248 ret = len;
249 }
250 }
251 free_page((unsigned long)page);
252 return ret;
253}
254
255static ssize_t get_mm_cmdline(struct mm_struct *mm, char __user *buf,
256 size_t count, loff_t *ppos)
257{
258 unsigned long arg_start, arg_end, env_start, env_end;
259 unsigned long pos, len;
260 char *page, c;
261
262 /* Check if process spawned far enough to have cmdline. */
263 if (!mm->env_end)
264 return 0;
265
266 spin_lock(&mm->arg_lock);
267 arg_start = mm->arg_start;
268 arg_end = mm->arg_end;
269 env_start = mm->env_start;
270 env_end = mm->env_end;
271 spin_unlock(&mm->arg_lock);
272
273 if (arg_start >= arg_end)
274 return 0;
275
276 /*
277 * We allow setproctitle() to overwrite the argument
278 * strings, and overflow past the original end. But
279 * only when it overflows into the environment area.
280 */
281 if (env_start != arg_end || env_end < env_start)
282 env_start = env_end = arg_end;
283 len = env_end - arg_start;
284
285 /* We're not going to care if "*ppos" has high bits set */
286 pos = *ppos;
287 if (pos >= len)
288 return 0;
289 if (count > len - pos)
290 count = len - pos;
291 if (!count)
292 return 0;
293
294 /*
295 * Magical special case: if the argv[] end byte is not
296 * zero, the user has overwritten it with setproctitle(3).
297 *
298 * Possible future enhancement: do this only once when
299 * pos is 0, and set a flag in the 'struct file'.
300 */
301 if (access_remote_vm(mm, arg_end-1, &c, 1, FOLL_ANON) == 1 && c)
302 return get_mm_proctitle(mm, buf, count, pos, arg_start);
303
304 /*
305 * For the non-setproctitle() case we limit things strictly
306 * to the [arg_start, arg_end[ range.
307 */
308 pos += arg_start;
309 if (pos < arg_start || pos >= arg_end)
310 return 0;
311 if (count > arg_end - pos)
312 count = arg_end - pos;
313
314 page = (char *)__get_free_page(GFP_KERNEL);
315 if (!page)
316 return -ENOMEM;
317
318 len = 0;
319 while (count) {
320 int got;
321 size_t size = min_t(size_t, PAGE_SIZE, count);
322
323 got = access_remote_vm(mm, pos, page, size, FOLL_ANON);
324 if (got <= 0)
325 break;
326 got -= copy_to_user(buf, page, got);
327 if (unlikely(!got)) {
328 if (!len)
329 len = -EFAULT;
330 break;
331 }
332 pos += got;
333 buf += got;
334 len += got;
335 count -= got;
336 }
337
338 free_page((unsigned long)page);
339 return len;
340}
341
342static ssize_t get_task_cmdline(struct task_struct *tsk, char __user *buf,
343 size_t count, loff_t *pos)
344{
345 struct mm_struct *mm;
346 ssize_t ret;
347
348 mm = get_task_mm(tsk);
349 if (!mm)
350 return 0;
351
352 ret = get_mm_cmdline(mm, buf, count, pos);
353 mmput(mm);
354 return ret;
355}
356
357static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
358 size_t count, loff_t *pos)
359{
360 struct task_struct *tsk;
361 ssize_t ret;
362
363 BUG_ON(*pos < 0);
364
365 tsk = get_proc_task(file_inode(file));
366 if (!tsk)
367 return -ESRCH;
368 ret = get_task_cmdline(tsk, buf, count, pos);
369 put_task_struct(tsk);
370 if (ret > 0)
371 *pos += ret;
372 return ret;
373}
374
375static const struct file_operations proc_pid_cmdline_ops = {
376 .read = proc_pid_cmdline_read,
377 .llseek = generic_file_llseek,
378};
379
380#ifdef CONFIG_KALLSYMS
381/*
382 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
383 * Returns the resolved symbol. If that fails, simply return the address.
384 */
385static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
386 struct pid *pid, struct task_struct *task)
387{
388 unsigned long wchan;
389 char symname[KSYM_NAME_LEN];
390
391 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
392 goto print0;
393
394 wchan = get_wchan(task);
395 if (wchan && !lookup_symbol_name(wchan, symname)) {
396 seq_puts(m, symname);
397 return 0;
398 }
399
400print0:
401 seq_putc(m, '0');
402 return 0;
403}
404#endif /* CONFIG_KALLSYMS */
405
406static int lock_trace(struct task_struct *task)
407{
408 int err = down_read_killable(&task->signal->exec_update_lock);
409 if (err)
410 return err;
411 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
412 up_read(&task->signal->exec_update_lock);
413 return -EPERM;
414 }
415 return 0;
416}
417
418static void unlock_trace(struct task_struct *task)
419{
420 up_read(&task->signal->exec_update_lock);
421}
422
423#ifdef CONFIG_STACKTRACE
424
425#define MAX_STACK_TRACE_DEPTH 64
426
427static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
428 struct pid *pid, struct task_struct *task)
429{
430 unsigned long *entries;
431 int err;
432
433 /*
434 * The ability to racily run the kernel stack unwinder on a running task
435 * and then observe the unwinder output is scary; while it is useful for
436 * debugging kernel issues, it can also allow an attacker to leak kernel
437 * stack contents.
438 * Doing this in a manner that is at least safe from races would require
439 * some work to ensure that the remote task can not be scheduled; and
440 * even then, this would still expose the unwinder as local attack
441 * surface.
442 * Therefore, this interface is restricted to root.
443 */
444 if (!file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN))
445 return -EACCES;
446
447 entries = kmalloc_array(MAX_STACK_TRACE_DEPTH, sizeof(*entries),
448 GFP_KERNEL);
449 if (!entries)
450 return -ENOMEM;
451
452 err = lock_trace(task);
453 if (!err) {
454 unsigned int i, nr_entries;
455
456 nr_entries = stack_trace_save_tsk(task, entries,
457 MAX_STACK_TRACE_DEPTH, 0);
458
459 for (i = 0; i < nr_entries; i++) {
460 seq_printf(m, "[<0>] %pB\n", (void *)entries[i]);
461 }
462
463 unlock_trace(task);
464 }
465 kfree(entries);
466
467 return err;
468}
469#endif
470
471#ifdef CONFIG_SCHED_INFO
472/*
473 * Provides /proc/PID/schedstat
474 */
475static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
476 struct pid *pid, struct task_struct *task)
477{
478 if (unlikely(!sched_info_on()))
479 seq_puts(m, "0 0 0\n");
480 else
481 seq_printf(m, "%llu %llu %lu\n",
482 (unsigned long long)task->se.sum_exec_runtime,
483 (unsigned long long)task->sched_info.run_delay,
484 task->sched_info.pcount);
485
486 return 0;
487}
488#endif
489
490#ifdef CONFIG_LATENCYTOP
491static int lstats_show_proc(struct seq_file *m, void *v)
492{
493 int i;
494 struct inode *inode = m->private;
495 struct task_struct *task = get_proc_task(inode);
496
497 if (!task)
498 return -ESRCH;
499 seq_puts(m, "Latency Top version : v0.1\n");
500 for (i = 0; i < LT_SAVECOUNT; i++) {
501 struct latency_record *lr = &task->latency_record[i];
502 if (lr->backtrace[0]) {
503 int q;
504 seq_printf(m, "%i %li %li",
505 lr->count, lr->time, lr->max);
506 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
507 unsigned long bt = lr->backtrace[q];
508
509 if (!bt)
510 break;
511 seq_printf(m, " %ps", (void *)bt);
512 }
513 seq_putc(m, '\n');
514 }
515
516 }
517 put_task_struct(task);
518 return 0;
519}
520
521static int lstats_open(struct inode *inode, struct file *file)
522{
523 return single_open(file, lstats_show_proc, inode);
524}
525
526static ssize_t lstats_write(struct file *file, const char __user *buf,
527 size_t count, loff_t *offs)
528{
529 struct task_struct *task = get_proc_task(file_inode(file));
530
531 if (!task)
532 return -ESRCH;
533 clear_tsk_latency_tracing(task);
534 put_task_struct(task);
535
536 return count;
537}
538
539static const struct file_operations proc_lstats_operations = {
540 .open = lstats_open,
541 .read = seq_read,
542 .write = lstats_write,
543 .llseek = seq_lseek,
544 .release = single_release,
545};
546
547#endif
548
549static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
550 struct pid *pid, struct task_struct *task)
551{
552 unsigned long totalpages = totalram_pages() + total_swap_pages;
553 unsigned long points = 0;
554 long badness;
555
556 badness = oom_badness(task, totalpages);
557 /*
558 * Special case OOM_SCORE_ADJ_MIN for all others scale the
559 * badness value into [0, 2000] range which we have been
560 * exporting for a long time so userspace might depend on it.
561 */
562 if (badness != LONG_MIN)
563 points = (1000 + badness * 1000 / (long)totalpages) * 2 / 3;
564
565 seq_printf(m, "%lu\n", points);
566
567 return 0;
568}
569
570struct limit_names {
571 const char *name;
572 const char *unit;
573};
574
575static const struct limit_names lnames[RLIM_NLIMITS] = {
576 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
577 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
578 [RLIMIT_DATA] = {"Max data size", "bytes"},
579 [RLIMIT_STACK] = {"Max stack size", "bytes"},
580 [RLIMIT_CORE] = {"Max core file size", "bytes"},
581 [RLIMIT_RSS] = {"Max resident set", "bytes"},
582 [RLIMIT_NPROC] = {"Max processes", "processes"},
583 [RLIMIT_NOFILE] = {"Max open files", "files"},
584 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
585 [RLIMIT_AS] = {"Max address space", "bytes"},
586 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
587 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
588 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
589 [RLIMIT_NICE] = {"Max nice priority", NULL},
590 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
591 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
592};
593
594/* Display limits for a process */
595static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
596 struct pid *pid, struct task_struct *task)
597{
598 unsigned int i;
599 unsigned long flags;
600
601 struct rlimit rlim[RLIM_NLIMITS];
602
603 if (!lock_task_sighand(task, &flags))
604 return 0;
605 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
606 unlock_task_sighand(task, &flags);
607
608 /*
609 * print the file header
610 */
611 seq_puts(m, "Limit "
612 "Soft Limit "
613 "Hard Limit "
614 "Units \n");
615
616 for (i = 0; i < RLIM_NLIMITS; i++) {
617 if (rlim[i].rlim_cur == RLIM_INFINITY)
618 seq_printf(m, "%-25s %-20s ",
619 lnames[i].name, "unlimited");
620 else
621 seq_printf(m, "%-25s %-20lu ",
622 lnames[i].name, rlim[i].rlim_cur);
623
624 if (rlim[i].rlim_max == RLIM_INFINITY)
625 seq_printf(m, "%-20s ", "unlimited");
626 else
627 seq_printf(m, "%-20lu ", rlim[i].rlim_max);
628
629 if (lnames[i].unit)
630 seq_printf(m, "%-10s\n", lnames[i].unit);
631 else
632 seq_putc(m, '\n');
633 }
634
635 return 0;
636}
637
638#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
639static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
640 struct pid *pid, struct task_struct *task)
641{
642 struct syscall_info info;
643 u64 *args = &info.data.args[0];
644 int res;
645
646 res = lock_trace(task);
647 if (res)
648 return res;
649
650 if (task_current_syscall(task, &info))
651 seq_puts(m, "running\n");
652 else if (info.data.nr < 0)
653 seq_printf(m, "%d 0x%llx 0x%llx\n",
654 info.data.nr, info.sp, info.data.instruction_pointer);
655 else
656 seq_printf(m,
657 "%d 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx 0x%llx\n",
658 info.data.nr,
659 args[0], args[1], args[2], args[3], args[4], args[5],
660 info.sp, info.data.instruction_pointer);
661 unlock_trace(task);
662
663 return 0;
664}
665#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
666
667/************************************************************************/
668/* Here the fs part begins */
669/************************************************************************/
670
671/* permission checks */
672static bool proc_fd_access_allowed(struct inode *inode)
673{
674 struct task_struct *task;
675 bool allowed = false;
676 /* Allow access to a task's file descriptors if it is us or we
677 * may use ptrace attach to the process and find out that
678 * information.
679 */
680 task = get_proc_task(inode);
681 if (task) {
682 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
683 put_task_struct(task);
684 }
685 return allowed;
686}
687
688int proc_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
689 struct iattr *attr)
690{
691 int error;
692 struct inode *inode = d_inode(dentry);
693
694 if (attr->ia_valid & ATTR_MODE)
695 return -EPERM;
696
697 error = setattr_prepare(&init_user_ns, dentry, attr);
698 if (error)
699 return error;
700
701 setattr_copy(&init_user_ns, inode, attr);
702 mark_inode_dirty(inode);
703 return 0;
704}
705
706/*
707 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
708 * or euid/egid (for hide_pid_min=2)?
709 */
710static bool has_pid_permissions(struct proc_fs_info *fs_info,
711 struct task_struct *task,
712 enum proc_hidepid hide_pid_min)
713{
714 /*
715 * If 'hidpid' mount option is set force a ptrace check,
716 * we indicate that we are using a filesystem syscall
717 * by passing PTRACE_MODE_READ_FSCREDS
718 */
719 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE)
720 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
721
722 if (fs_info->hide_pid < hide_pid_min)
723 return true;
724 if (in_group_p(fs_info->pid_gid))
725 return true;
726 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
727}
728
729
730static int proc_pid_permission(struct user_namespace *mnt_userns,
731 struct inode *inode, int mask)
732{
733 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
734 struct task_struct *task;
735 bool has_perms;
736
737 task = get_proc_task(inode);
738 if (!task)
739 return -ESRCH;
740 has_perms = has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS);
741 put_task_struct(task);
742
743 if (!has_perms) {
744 if (fs_info->hide_pid == HIDEPID_INVISIBLE) {
745 /*
746 * Let's make getdents(), stat(), and open()
747 * consistent with each other. If a process
748 * may not stat() a file, it shouldn't be seen
749 * in procfs at all.
750 */
751 return -ENOENT;
752 }
753
754 return -EPERM;
755 }
756 return generic_permission(&init_user_ns, inode, mask);
757}
758
759
760
761static const struct inode_operations proc_def_inode_operations = {
762 .setattr = proc_setattr,
763};
764
765static int proc_single_show(struct seq_file *m, void *v)
766{
767 struct inode *inode = m->private;
768 struct pid_namespace *ns = proc_pid_ns(inode->i_sb);
769 struct pid *pid = proc_pid(inode);
770 struct task_struct *task;
771 int ret;
772
773 task = get_pid_task(pid, PIDTYPE_PID);
774 if (!task)
775 return -ESRCH;
776
777 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
778
779 put_task_struct(task);
780 return ret;
781}
782
783static int proc_single_open(struct inode *inode, struct file *filp)
784{
785 return single_open(filp, proc_single_show, inode);
786}
787
788static const struct file_operations proc_single_file_operations = {
789 .open = proc_single_open,
790 .read = seq_read,
791 .llseek = seq_lseek,
792 .release = single_release,
793};
794
795
796struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
797{
798 struct task_struct *task = get_proc_task(inode);
799 struct mm_struct *mm = ERR_PTR(-ESRCH);
800
801 if (task) {
802 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
803 put_task_struct(task);
804
805 if (!IS_ERR_OR_NULL(mm)) {
806 /* ensure this mm_struct can't be freed */
807 mmgrab(mm);
808 /* but do not pin its memory */
809 mmput(mm);
810 }
811 }
812
813 return mm;
814}
815
816static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
817{
818 struct mm_struct *mm = proc_mem_open(inode, mode);
819
820 if (IS_ERR(mm))
821 return PTR_ERR(mm);
822
823 file->private_data = mm;
824 return 0;
825}
826
827static int mem_open(struct inode *inode, struct file *file)
828{
829 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
830
831 /* OK to pass negative loff_t, we can catch out-of-range */
832 file->f_mode |= FMODE_UNSIGNED_OFFSET;
833
834 return ret;
835}
836
837static ssize_t mem_rw(struct file *file, char __user *buf,
838 size_t count, loff_t *ppos, int write)
839{
840 struct mm_struct *mm = file->private_data;
841 unsigned long addr = *ppos;
842 ssize_t copied;
843 char *page;
844 unsigned int flags;
845
846 if (!mm)
847 return 0;
848
849 page = (char *)__get_free_page(GFP_KERNEL);
850 if (!page)
851 return -ENOMEM;
852
853 copied = 0;
854 if (!mmget_not_zero(mm))
855 goto free;
856
857 flags = FOLL_FORCE | (write ? FOLL_WRITE : 0);
858
859 while (count > 0) {
860 size_t this_len = min_t(size_t, count, PAGE_SIZE);
861
862 if (write && copy_from_user(page, buf, this_len)) {
863 copied = -EFAULT;
864 break;
865 }
866
867 this_len = access_remote_vm(mm, addr, page, this_len, flags);
868 if (!this_len) {
869 if (!copied)
870 copied = -EIO;
871 break;
872 }
873
874 if (!write && copy_to_user(buf, page, this_len)) {
875 copied = -EFAULT;
876 break;
877 }
878
879 buf += this_len;
880 addr += this_len;
881 copied += this_len;
882 count -= this_len;
883 }
884 *ppos = addr;
885
886 mmput(mm);
887free:
888 free_page((unsigned long) page);
889 return copied;
890}
891
892static ssize_t mem_read(struct file *file, char __user *buf,
893 size_t count, loff_t *ppos)
894{
895 return mem_rw(file, buf, count, ppos, 0);
896}
897
898static ssize_t mem_write(struct file *file, const char __user *buf,
899 size_t count, loff_t *ppos)
900{
901 return mem_rw(file, (char __user*)buf, count, ppos, 1);
902}
903
904loff_t mem_lseek(struct file *file, loff_t offset, int orig)
905{
906 switch (orig) {
907 case 0:
908 file->f_pos = offset;
909 break;
910 case 1:
911 file->f_pos += offset;
912 break;
913 default:
914 return -EINVAL;
915 }
916 force_successful_syscall_return();
917 return file->f_pos;
918}
919
920static int mem_release(struct inode *inode, struct file *file)
921{
922 struct mm_struct *mm = file->private_data;
923 if (mm)
924 mmdrop(mm);
925 return 0;
926}
927
928static const struct file_operations proc_mem_operations = {
929 .llseek = mem_lseek,
930 .read = mem_read,
931 .write = mem_write,
932 .open = mem_open,
933 .release = mem_release,
934};
935
936static int environ_open(struct inode *inode, struct file *file)
937{
938 return __mem_open(inode, file, PTRACE_MODE_READ);
939}
940
941static ssize_t environ_read(struct file *file, char __user *buf,
942 size_t count, loff_t *ppos)
943{
944 char *page;
945 unsigned long src = *ppos;
946 int ret = 0;
947 struct mm_struct *mm = file->private_data;
948 unsigned long env_start, env_end;
949
950 /* Ensure the process spawned far enough to have an environment. */
951 if (!mm || !mm->env_end)
952 return 0;
953
954 page = (char *)__get_free_page(GFP_KERNEL);
955 if (!page)
956 return -ENOMEM;
957
958 ret = 0;
959 if (!mmget_not_zero(mm))
960 goto free;
961
962 spin_lock(&mm->arg_lock);
963 env_start = mm->env_start;
964 env_end = mm->env_end;
965 spin_unlock(&mm->arg_lock);
966
967 while (count > 0) {
968 size_t this_len, max_len;
969 int retval;
970
971 if (src >= (env_end - env_start))
972 break;
973
974 this_len = env_end - (env_start + src);
975
976 max_len = min_t(size_t, PAGE_SIZE, count);
977 this_len = min(max_len, this_len);
978
979 retval = access_remote_vm(mm, (env_start + src), page, this_len, FOLL_ANON);
980
981 if (retval <= 0) {
982 ret = retval;
983 break;
984 }
985
986 if (copy_to_user(buf, page, retval)) {
987 ret = -EFAULT;
988 break;
989 }
990
991 ret += retval;
992 src += retval;
993 buf += retval;
994 count -= retval;
995 }
996 *ppos = src;
997 mmput(mm);
998
999free:
1000 free_page((unsigned long) page);
1001 return ret;
1002}
1003
1004static const struct file_operations proc_environ_operations = {
1005 .open = environ_open,
1006 .read = environ_read,
1007 .llseek = generic_file_llseek,
1008 .release = mem_release,
1009};
1010
1011static int auxv_open(struct inode *inode, struct file *file)
1012{
1013 return __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
1014}
1015
1016static ssize_t auxv_read(struct file *file, char __user *buf,
1017 size_t count, loff_t *ppos)
1018{
1019 struct mm_struct *mm = file->private_data;
1020 unsigned int nwords = 0;
1021
1022 if (!mm)
1023 return 0;
1024 do {
1025 nwords += 2;
1026 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1027 return simple_read_from_buffer(buf, count, ppos, mm->saved_auxv,
1028 nwords * sizeof(mm->saved_auxv[0]));
1029}
1030
1031static const struct file_operations proc_auxv_operations = {
1032 .open = auxv_open,
1033 .read = auxv_read,
1034 .llseek = generic_file_llseek,
1035 .release = mem_release,
1036};
1037
1038static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1039 loff_t *ppos)
1040{
1041 struct task_struct *task = get_proc_task(file_inode(file));
1042 char buffer[PROC_NUMBUF];
1043 int oom_adj = OOM_ADJUST_MIN;
1044 size_t len;
1045
1046 if (!task)
1047 return -ESRCH;
1048 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1049 oom_adj = OOM_ADJUST_MAX;
1050 else
1051 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1052 OOM_SCORE_ADJ_MAX;
1053 put_task_struct(task);
1054 if (oom_adj > OOM_ADJUST_MAX)
1055 oom_adj = OOM_ADJUST_MAX;
1056 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1057 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1058}
1059
1060static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
1061{
1062 struct mm_struct *mm = NULL;
1063 struct task_struct *task;
1064 int err = 0;
1065
1066 task = get_proc_task(file_inode(file));
1067 if (!task)
1068 return -ESRCH;
1069
1070 mutex_lock(&oom_adj_mutex);
1071 if (legacy) {
1072 if (oom_adj < task->signal->oom_score_adj &&
1073 !capable(CAP_SYS_RESOURCE)) {
1074 err = -EACCES;
1075 goto err_unlock;
1076 }
1077 /*
1078 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1079 * /proc/pid/oom_score_adj instead.
1080 */
1081 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1082 current->comm, task_pid_nr(current), task_pid_nr(task),
1083 task_pid_nr(task));
1084 } else {
1085 if ((short)oom_adj < task->signal->oom_score_adj_min &&
1086 !capable(CAP_SYS_RESOURCE)) {
1087 err = -EACCES;
1088 goto err_unlock;
1089 }
1090 }
1091
1092 /*
1093 * Make sure we will check other processes sharing the mm if this is
1094 * not vfrok which wants its own oom_score_adj.
1095 * pin the mm so it doesn't go away and get reused after task_unlock
1096 */
1097 if (!task->vfork_done) {
1098 struct task_struct *p = find_lock_task_mm(task);
1099
1100 if (p) {
1101 if (test_bit(MMF_MULTIPROCESS, &p->mm->flags)) {
1102 mm = p->mm;
1103 mmgrab(mm);
1104 }
1105 task_unlock(p);
1106 }
1107 }
1108
1109 task->signal->oom_score_adj = oom_adj;
1110 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1111 task->signal->oom_score_adj_min = (short)oom_adj;
1112 trace_oom_score_adj_update(task);
1113
1114 if (mm) {
1115 struct task_struct *p;
1116
1117 rcu_read_lock();
1118 for_each_process(p) {
1119 if (same_thread_group(task, p))
1120 continue;
1121
1122 /* do not touch kernel threads or the global init */
1123 if (p->flags & PF_KTHREAD || is_global_init(p))
1124 continue;
1125
1126 task_lock(p);
1127 if (!p->vfork_done && process_shares_mm(p, mm)) {
1128 p->signal->oom_score_adj = oom_adj;
1129 if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
1130 p->signal->oom_score_adj_min = (short)oom_adj;
1131 }
1132 task_unlock(p);
1133 }
1134 rcu_read_unlock();
1135 mmdrop(mm);
1136 }
1137err_unlock:
1138 mutex_unlock(&oom_adj_mutex);
1139 put_task_struct(task);
1140 return err;
1141}
1142
1143/*
1144 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1145 * kernels. The effective policy is defined by oom_score_adj, which has a
1146 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1147 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1148 * Processes that become oom disabled via oom_adj will still be oom disabled
1149 * with this implementation.
1150 *
1151 * oom_adj cannot be removed since existing userspace binaries use it.
1152 */
1153static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1154 size_t count, loff_t *ppos)
1155{
1156 char buffer[PROC_NUMBUF];
1157 int oom_adj;
1158 int err;
1159
1160 memset(buffer, 0, sizeof(buffer));
1161 if (count > sizeof(buffer) - 1)
1162 count = sizeof(buffer) - 1;
1163 if (copy_from_user(buffer, buf, count)) {
1164 err = -EFAULT;
1165 goto out;
1166 }
1167
1168 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1169 if (err)
1170 goto out;
1171 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1172 oom_adj != OOM_DISABLE) {
1173 err = -EINVAL;
1174 goto out;
1175 }
1176
1177 /*
1178 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1179 * value is always attainable.
1180 */
1181 if (oom_adj == OOM_ADJUST_MAX)
1182 oom_adj = OOM_SCORE_ADJ_MAX;
1183 else
1184 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1185
1186 err = __set_oom_adj(file, oom_adj, true);
1187out:
1188 return err < 0 ? err : count;
1189}
1190
1191static const struct file_operations proc_oom_adj_operations = {
1192 .read = oom_adj_read,
1193 .write = oom_adj_write,
1194 .llseek = generic_file_llseek,
1195};
1196
1197static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1198 size_t count, loff_t *ppos)
1199{
1200 struct task_struct *task = get_proc_task(file_inode(file));
1201 char buffer[PROC_NUMBUF];
1202 short oom_score_adj = OOM_SCORE_ADJ_MIN;
1203 size_t len;
1204
1205 if (!task)
1206 return -ESRCH;
1207 oom_score_adj = task->signal->oom_score_adj;
1208 put_task_struct(task);
1209 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
1210 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1211}
1212
1213static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1214 size_t count, loff_t *ppos)
1215{
1216 char buffer[PROC_NUMBUF];
1217 int oom_score_adj;
1218 int err;
1219
1220 memset(buffer, 0, sizeof(buffer));
1221 if (count > sizeof(buffer) - 1)
1222 count = sizeof(buffer) - 1;
1223 if (copy_from_user(buffer, buf, count)) {
1224 err = -EFAULT;
1225 goto out;
1226 }
1227
1228 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1229 if (err)
1230 goto out;
1231 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1232 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1233 err = -EINVAL;
1234 goto out;
1235 }
1236
1237 err = __set_oom_adj(file, oom_score_adj, false);
1238out:
1239 return err < 0 ? err : count;
1240}
1241
1242static const struct file_operations proc_oom_score_adj_operations = {
1243 .read = oom_score_adj_read,
1244 .write = oom_score_adj_write,
1245 .llseek = default_llseek,
1246};
1247
1248#ifdef CONFIG_AUDIT
1249#define TMPBUFLEN 11
1250static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1251 size_t count, loff_t *ppos)
1252{
1253 struct inode * inode = file_inode(file);
1254 struct task_struct *task = get_proc_task(inode);
1255 ssize_t length;
1256 char tmpbuf[TMPBUFLEN];
1257
1258 if (!task)
1259 return -ESRCH;
1260 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1261 from_kuid(file->f_cred->user_ns,
1262 audit_get_loginuid(task)));
1263 put_task_struct(task);
1264 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1265}
1266
1267static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1268 size_t count, loff_t *ppos)
1269{
1270 struct inode * inode = file_inode(file);
1271 uid_t loginuid;
1272 kuid_t kloginuid;
1273 int rv;
1274
1275 /* Don't let kthreads write their own loginuid */
1276 if (current->flags & PF_KTHREAD)
1277 return -EPERM;
1278
1279 rcu_read_lock();
1280 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1281 rcu_read_unlock();
1282 return -EPERM;
1283 }
1284 rcu_read_unlock();
1285
1286 if (*ppos != 0) {
1287 /* No partial writes. */
1288 return -EINVAL;
1289 }
1290
1291 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1292 if (rv < 0)
1293 return rv;
1294
1295 /* is userspace tring to explicitly UNSET the loginuid? */
1296 if (loginuid == AUDIT_UID_UNSET) {
1297 kloginuid = INVALID_UID;
1298 } else {
1299 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
1300 if (!uid_valid(kloginuid))
1301 return -EINVAL;
1302 }
1303
1304 rv = audit_set_loginuid(kloginuid);
1305 if (rv < 0)
1306 return rv;
1307 return count;
1308}
1309
1310static const struct file_operations proc_loginuid_operations = {
1311 .read = proc_loginuid_read,
1312 .write = proc_loginuid_write,
1313 .llseek = generic_file_llseek,
1314};
1315
1316static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1317 size_t count, loff_t *ppos)
1318{
1319 struct inode * inode = file_inode(file);
1320 struct task_struct *task = get_proc_task(inode);
1321 ssize_t length;
1322 char tmpbuf[TMPBUFLEN];
1323
1324 if (!task)
1325 return -ESRCH;
1326 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1327 audit_get_sessionid(task));
1328 put_task_struct(task);
1329 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1330}
1331
1332static const struct file_operations proc_sessionid_operations = {
1333 .read = proc_sessionid_read,
1334 .llseek = generic_file_llseek,
1335};
1336#endif
1337
1338#ifdef CONFIG_FAULT_INJECTION
1339static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1340 size_t count, loff_t *ppos)
1341{
1342 struct task_struct *task = get_proc_task(file_inode(file));
1343 char buffer[PROC_NUMBUF];
1344 size_t len;
1345 int make_it_fail;
1346
1347 if (!task)
1348 return -ESRCH;
1349 make_it_fail = task->make_it_fail;
1350 put_task_struct(task);
1351
1352 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1353
1354 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1355}
1356
1357static ssize_t proc_fault_inject_write(struct file * file,
1358 const char __user * buf, size_t count, loff_t *ppos)
1359{
1360 struct task_struct *task;
1361 char buffer[PROC_NUMBUF];
1362 int make_it_fail;
1363 int rv;
1364
1365 if (!capable(CAP_SYS_RESOURCE))
1366 return -EPERM;
1367 memset(buffer, 0, sizeof(buffer));
1368 if (count > sizeof(buffer) - 1)
1369 count = sizeof(buffer) - 1;
1370 if (copy_from_user(buffer, buf, count))
1371 return -EFAULT;
1372 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1373 if (rv < 0)
1374 return rv;
1375 if (make_it_fail < 0 || make_it_fail > 1)
1376 return -EINVAL;
1377
1378 task = get_proc_task(file_inode(file));
1379 if (!task)
1380 return -ESRCH;
1381 task->make_it_fail = make_it_fail;
1382 put_task_struct(task);
1383
1384 return count;
1385}
1386
1387static const struct file_operations proc_fault_inject_operations = {
1388 .read = proc_fault_inject_read,
1389 .write = proc_fault_inject_write,
1390 .llseek = generic_file_llseek,
1391};
1392
1393static ssize_t proc_fail_nth_write(struct file *file, const char __user *buf,
1394 size_t count, loff_t *ppos)
1395{
1396 struct task_struct *task;
1397 int err;
1398 unsigned int n;
1399
1400 err = kstrtouint_from_user(buf, count, 0, &n);
1401 if (err)
1402 return err;
1403
1404 task = get_proc_task(file_inode(file));
1405 if (!task)
1406 return -ESRCH;
1407 task->fail_nth = n;
1408 put_task_struct(task);
1409
1410 return count;
1411}
1412
1413static ssize_t proc_fail_nth_read(struct file *file, char __user *buf,
1414 size_t count, loff_t *ppos)
1415{
1416 struct task_struct *task;
1417 char numbuf[PROC_NUMBUF];
1418 ssize_t len;
1419
1420 task = get_proc_task(file_inode(file));
1421 if (!task)
1422 return -ESRCH;
1423 len = snprintf(numbuf, sizeof(numbuf), "%u\n", task->fail_nth);
1424 put_task_struct(task);
1425 return simple_read_from_buffer(buf, count, ppos, numbuf, len);
1426}
1427
1428static const struct file_operations proc_fail_nth_operations = {
1429 .read = proc_fail_nth_read,
1430 .write = proc_fail_nth_write,
1431};
1432#endif
1433
1434
1435#ifdef CONFIG_SCHED_DEBUG
1436/*
1437 * Print out various scheduling related per-task fields:
1438 */
1439static int sched_show(struct seq_file *m, void *v)
1440{
1441 struct inode *inode = m->private;
1442 struct pid_namespace *ns = proc_pid_ns(inode->i_sb);
1443 struct task_struct *p;
1444
1445 p = get_proc_task(inode);
1446 if (!p)
1447 return -ESRCH;
1448 proc_sched_show_task(p, ns, m);
1449
1450 put_task_struct(p);
1451
1452 return 0;
1453}
1454
1455static ssize_t
1456sched_write(struct file *file, const char __user *buf,
1457 size_t count, loff_t *offset)
1458{
1459 struct inode *inode = file_inode(file);
1460 struct task_struct *p;
1461
1462 p = get_proc_task(inode);
1463 if (!p)
1464 return -ESRCH;
1465 proc_sched_set_task(p);
1466
1467 put_task_struct(p);
1468
1469 return count;
1470}
1471
1472static int sched_open(struct inode *inode, struct file *filp)
1473{
1474 return single_open(filp, sched_show, inode);
1475}
1476
1477static const struct file_operations proc_pid_sched_operations = {
1478 .open = sched_open,
1479 .read = seq_read,
1480 .write = sched_write,
1481 .llseek = seq_lseek,
1482 .release = single_release,
1483};
1484
1485#endif
1486
1487#ifdef CONFIG_SCHED_AUTOGROUP
1488/*
1489 * Print out autogroup related information:
1490 */
1491static int sched_autogroup_show(struct seq_file *m, void *v)
1492{
1493 struct inode *inode = m->private;
1494 struct task_struct *p;
1495
1496 p = get_proc_task(inode);
1497 if (!p)
1498 return -ESRCH;
1499 proc_sched_autogroup_show_task(p, m);
1500
1501 put_task_struct(p);
1502
1503 return 0;
1504}
1505
1506static ssize_t
1507sched_autogroup_write(struct file *file, const char __user *buf,
1508 size_t count, loff_t *offset)
1509{
1510 struct inode *inode = file_inode(file);
1511 struct task_struct *p;
1512 char buffer[PROC_NUMBUF];
1513 int nice;
1514 int err;
1515
1516 memset(buffer, 0, sizeof(buffer));
1517 if (count > sizeof(buffer) - 1)
1518 count = sizeof(buffer) - 1;
1519 if (copy_from_user(buffer, buf, count))
1520 return -EFAULT;
1521
1522 err = kstrtoint(strstrip(buffer), 0, &nice);
1523 if (err < 0)
1524 return err;
1525
1526 p = get_proc_task(inode);
1527 if (!p)
1528 return -ESRCH;
1529
1530 err = proc_sched_autogroup_set_nice(p, nice);
1531 if (err)
1532 count = err;
1533
1534 put_task_struct(p);
1535
1536 return count;
1537}
1538
1539static int sched_autogroup_open(struct inode *inode, struct file *filp)
1540{
1541 int ret;
1542
1543 ret = single_open(filp, sched_autogroup_show, NULL);
1544 if (!ret) {
1545 struct seq_file *m = filp->private_data;
1546
1547 m->private = inode;
1548 }
1549 return ret;
1550}
1551
1552static const struct file_operations proc_pid_sched_autogroup_operations = {
1553 .open = sched_autogroup_open,
1554 .read = seq_read,
1555 .write = sched_autogroup_write,
1556 .llseek = seq_lseek,
1557 .release = single_release,
1558};
1559
1560#endif /* CONFIG_SCHED_AUTOGROUP */
1561
1562#ifdef CONFIG_TIME_NS
1563static int timens_offsets_show(struct seq_file *m, void *v)
1564{
1565 struct task_struct *p;
1566
1567 p = get_proc_task(file_inode(m->file));
1568 if (!p)
1569 return -ESRCH;
1570 proc_timens_show_offsets(p, m);
1571
1572 put_task_struct(p);
1573
1574 return 0;
1575}
1576
1577static ssize_t timens_offsets_write(struct file *file, const char __user *buf,
1578 size_t count, loff_t *ppos)
1579{
1580 struct inode *inode = file_inode(file);
1581 struct proc_timens_offset offsets[2];
1582 char *kbuf = NULL, *pos, *next_line;
1583 struct task_struct *p;
1584 int ret, noffsets;
1585
1586 /* Only allow < page size writes at the beginning of the file */
1587 if ((*ppos != 0) || (count >= PAGE_SIZE))
1588 return -EINVAL;
1589
1590 /* Slurp in the user data */
1591 kbuf = memdup_user_nul(buf, count);
1592 if (IS_ERR(kbuf))
1593 return PTR_ERR(kbuf);
1594
1595 /* Parse the user data */
1596 ret = -EINVAL;
1597 noffsets = 0;
1598 for (pos = kbuf; pos; pos = next_line) {
1599 struct proc_timens_offset *off = &offsets[noffsets];
1600 char clock[10];
1601 int err;
1602
1603 /* Find the end of line and ensure we don't look past it */
1604 next_line = strchr(pos, '\n');
1605 if (next_line) {
1606 *next_line = '\0';
1607 next_line++;
1608 if (*next_line == '\0')
1609 next_line = NULL;
1610 }
1611
1612 err = sscanf(pos, "%9s %lld %lu", clock,
1613 &off->val.tv_sec, &off->val.tv_nsec);
1614 if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC)
1615 goto out;
1616
1617 clock[sizeof(clock) - 1] = 0;
1618 if (strcmp(clock, "monotonic") == 0 ||
1619 strcmp(clock, __stringify(CLOCK_MONOTONIC)) == 0)
1620 off->clockid = CLOCK_MONOTONIC;
1621 else if (strcmp(clock, "boottime") == 0 ||
1622 strcmp(clock, __stringify(CLOCK_BOOTTIME)) == 0)
1623 off->clockid = CLOCK_BOOTTIME;
1624 else
1625 goto out;
1626
1627 noffsets++;
1628 if (noffsets == ARRAY_SIZE(offsets)) {
1629 if (next_line)
1630 count = next_line - kbuf;
1631 break;
1632 }
1633 }
1634
1635 ret = -ESRCH;
1636 p = get_proc_task(inode);
1637 if (!p)
1638 goto out;
1639 ret = proc_timens_set_offset(file, p, offsets, noffsets);
1640 put_task_struct(p);
1641 if (ret)
1642 goto out;
1643
1644 ret = count;
1645out:
1646 kfree(kbuf);
1647 return ret;
1648}
1649
1650static int timens_offsets_open(struct inode *inode, struct file *filp)
1651{
1652 return single_open(filp, timens_offsets_show, inode);
1653}
1654
1655static const struct file_operations proc_timens_offsets_operations = {
1656 .open = timens_offsets_open,
1657 .read = seq_read,
1658 .write = timens_offsets_write,
1659 .llseek = seq_lseek,
1660 .release = single_release,
1661};
1662#endif /* CONFIG_TIME_NS */
1663
1664static ssize_t comm_write(struct file *file, const char __user *buf,
1665 size_t count, loff_t *offset)
1666{
1667 struct inode *inode = file_inode(file);
1668 struct task_struct *p;
1669 char buffer[TASK_COMM_LEN];
1670 const size_t maxlen = sizeof(buffer) - 1;
1671
1672 memset(buffer, 0, sizeof(buffer));
1673 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
1674 return -EFAULT;
1675
1676 p = get_proc_task(inode);
1677 if (!p)
1678 return -ESRCH;
1679
1680 if (same_thread_group(current, p)) {
1681 set_task_comm(p, buffer);
1682 proc_comm_connector(p);
1683 }
1684 else
1685 count = -EINVAL;
1686
1687 put_task_struct(p);
1688
1689 return count;
1690}
1691
1692static int comm_show(struct seq_file *m, void *v)
1693{
1694 struct inode *inode = m->private;
1695 struct task_struct *p;
1696
1697 p = get_proc_task(inode);
1698 if (!p)
1699 return -ESRCH;
1700
1701 proc_task_name(m, p, false);
1702 seq_putc(m, '\n');
1703
1704 put_task_struct(p);
1705
1706 return 0;
1707}
1708
1709static int comm_open(struct inode *inode, struct file *filp)
1710{
1711 return single_open(filp, comm_show, inode);
1712}
1713
1714static const struct file_operations proc_pid_set_comm_operations = {
1715 .open = comm_open,
1716 .read = seq_read,
1717 .write = comm_write,
1718 .llseek = seq_lseek,
1719 .release = single_release,
1720};
1721
1722static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1723{
1724 struct task_struct *task;
1725 struct file *exe_file;
1726
1727 task = get_proc_task(d_inode(dentry));
1728 if (!task)
1729 return -ENOENT;
1730 exe_file = get_task_exe_file(task);
1731 put_task_struct(task);
1732 if (exe_file) {
1733 *exe_path = exe_file->f_path;
1734 path_get(&exe_file->f_path);
1735 fput(exe_file);
1736 return 0;
1737 } else
1738 return -ENOENT;
1739}
1740
1741static const char *proc_pid_get_link(struct dentry *dentry,
1742 struct inode *inode,
1743 struct delayed_call *done)
1744{
1745 struct path path;
1746 int error = -EACCES;
1747
1748 if (!dentry)
1749 return ERR_PTR(-ECHILD);
1750
1751 /* Are we allowed to snoop on the tasks file descriptors? */
1752 if (!proc_fd_access_allowed(inode))
1753 goto out;
1754
1755 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1756 if (error)
1757 goto out;
1758
1759 error = nd_jump_link(&path);
1760out:
1761 return ERR_PTR(error);
1762}
1763
1764static int do_proc_readlink(const struct path *path, char __user *buffer, int buflen)
1765{
1766 char *tmp = kmalloc(PATH_MAX, GFP_KERNEL);
1767 char *pathname;
1768 int len;
1769
1770 if (!tmp)
1771 return -ENOMEM;
1772
1773 pathname = d_path(path, tmp, PATH_MAX);
1774 len = PTR_ERR(pathname);
1775 if (IS_ERR(pathname))
1776 goto out;
1777 len = tmp + PATH_MAX - 1 - pathname;
1778
1779 if (len > buflen)
1780 len = buflen;
1781 if (copy_to_user(buffer, pathname, len))
1782 len = -EFAULT;
1783 out:
1784 kfree(tmp);
1785 return len;
1786}
1787
1788static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1789{
1790 int error = -EACCES;
1791 struct inode *inode = d_inode(dentry);
1792 struct path path;
1793
1794 /* Are we allowed to snoop on the tasks file descriptors? */
1795 if (!proc_fd_access_allowed(inode))
1796 goto out;
1797
1798 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1799 if (error)
1800 goto out;
1801
1802 error = do_proc_readlink(&path, buffer, buflen);
1803 path_put(&path);
1804out:
1805 return error;
1806}
1807
1808const struct inode_operations proc_pid_link_inode_operations = {
1809 .readlink = proc_pid_readlink,
1810 .get_link = proc_pid_get_link,
1811 .setattr = proc_setattr,
1812};
1813
1814
1815/* building an inode */
1816
1817void task_dump_owner(struct task_struct *task, umode_t mode,
1818 kuid_t *ruid, kgid_t *rgid)
1819{
1820 /* Depending on the state of dumpable compute who should own a
1821 * proc file for a task.
1822 */
1823 const struct cred *cred;
1824 kuid_t uid;
1825 kgid_t gid;
1826
1827 if (unlikely(task->flags & PF_KTHREAD)) {
1828 *ruid = GLOBAL_ROOT_UID;
1829 *rgid = GLOBAL_ROOT_GID;
1830 return;
1831 }
1832
1833 /* Default to the tasks effective ownership */
1834 rcu_read_lock();
1835 cred = __task_cred(task);
1836 uid = cred->euid;
1837 gid = cred->egid;
1838 rcu_read_unlock();
1839
1840 /*
1841 * Before the /proc/pid/status file was created the only way to read
1842 * the effective uid of a /process was to stat /proc/pid. Reading
1843 * /proc/pid/status is slow enough that procps and other packages
1844 * kept stating /proc/pid. To keep the rules in /proc simple I have
1845 * made this apply to all per process world readable and executable
1846 * directories.
1847 */
1848 if (mode != (S_IFDIR|S_IRUGO|S_IXUGO)) {
1849 struct mm_struct *mm;
1850 task_lock(task);
1851 mm = task->mm;
1852 /* Make non-dumpable tasks owned by some root */
1853 if (mm) {
1854 if (get_dumpable(mm) != SUID_DUMP_USER) {
1855 struct user_namespace *user_ns = mm->user_ns;
1856
1857 uid = make_kuid(user_ns, 0);
1858 if (!uid_valid(uid))
1859 uid = GLOBAL_ROOT_UID;
1860
1861 gid = make_kgid(user_ns, 0);
1862 if (!gid_valid(gid))
1863 gid = GLOBAL_ROOT_GID;
1864 }
1865 } else {
1866 uid = GLOBAL_ROOT_UID;
1867 gid = GLOBAL_ROOT_GID;
1868 }
1869 task_unlock(task);
1870 }
1871 *ruid = uid;
1872 *rgid = gid;
1873}
1874
1875void proc_pid_evict_inode(struct proc_inode *ei)
1876{
1877 struct pid *pid = ei->pid;
1878
1879 if (S_ISDIR(ei->vfs_inode.i_mode)) {
1880 spin_lock(&pid->lock);
1881 hlist_del_init_rcu(&ei->sibling_inodes);
1882 spin_unlock(&pid->lock);
1883 }
1884
1885 put_pid(pid);
1886}
1887
1888struct inode *proc_pid_make_inode(struct super_block *sb,
1889 struct task_struct *task, umode_t mode)
1890{
1891 struct inode * inode;
1892 struct proc_inode *ei;
1893 struct pid *pid;
1894
1895 /* We need a new inode */
1896
1897 inode = new_inode(sb);
1898 if (!inode)
1899 goto out;
1900
1901 /* Common stuff */
1902 ei = PROC_I(inode);
1903 inode->i_mode = mode;
1904 inode->i_ino = get_next_ino();
1905 inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
1906 inode->i_op = &proc_def_inode_operations;
1907
1908 /*
1909 * grab the reference to task.
1910 */
1911 pid = get_task_pid(task, PIDTYPE_PID);
1912 if (!pid)
1913 goto out_unlock;
1914
1915 /* Let the pid remember us for quick removal */
1916 ei->pid = pid;
1917
1918 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
1919 security_task_to_inode(task, inode);
1920
1921out:
1922 return inode;
1923
1924out_unlock:
1925 iput(inode);
1926 return NULL;
1927}
1928
1929/*
1930 * Generating an inode and adding it into @pid->inodes, so that task will
1931 * invalidate inode's dentry before being released.
1932 *
1933 * This helper is used for creating dir-type entries under '/proc' and
1934 * '/proc/<tgid>/task'. Other entries(eg. fd, stat) under '/proc/<tgid>'
1935 * can be released by invalidating '/proc/<tgid>' dentry.
1936 * In theory, dentries under '/proc/<tgid>/task' can also be released by
1937 * invalidating '/proc/<tgid>' dentry, we reserve it to handle single
1938 * thread exiting situation: Any one of threads should invalidate its
1939 * '/proc/<tgid>/task/<pid>' dentry before released.
1940 */
1941static struct inode *proc_pid_make_base_inode(struct super_block *sb,
1942 struct task_struct *task, umode_t mode)
1943{
1944 struct inode *inode;
1945 struct proc_inode *ei;
1946 struct pid *pid;
1947
1948 inode = proc_pid_make_inode(sb, task, mode);
1949 if (!inode)
1950 return NULL;
1951
1952 /* Let proc_flush_pid find this directory inode */
1953 ei = PROC_I(inode);
1954 pid = ei->pid;
1955 spin_lock(&pid->lock);
1956 hlist_add_head_rcu(&ei->sibling_inodes, &pid->inodes);
1957 spin_unlock(&pid->lock);
1958
1959 return inode;
1960}
1961
1962int pid_getattr(struct user_namespace *mnt_userns, const struct path *path,
1963 struct kstat *stat, u32 request_mask, unsigned int query_flags)
1964{
1965 struct inode *inode = d_inode(path->dentry);
1966 struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
1967 struct task_struct *task;
1968
1969 generic_fillattr(&init_user_ns, inode, stat);
1970
1971 stat->uid = GLOBAL_ROOT_UID;
1972 stat->gid = GLOBAL_ROOT_GID;
1973 rcu_read_lock();
1974 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1975 if (task) {
1976 if (!has_pid_permissions(fs_info, task, HIDEPID_INVISIBLE)) {
1977 rcu_read_unlock();
1978 /*
1979 * This doesn't prevent learning whether PID exists,
1980 * it only makes getattr() consistent with readdir().
1981 */
1982 return -ENOENT;
1983 }
1984 task_dump_owner(task, inode->i_mode, &stat->uid, &stat->gid);
1985 }
1986 rcu_read_unlock();
1987 return 0;
1988}
1989
1990/* dentry stuff */
1991
1992/*
1993 * Set <pid>/... inode ownership (can change due to setuid(), etc.)
1994 */
1995void pid_update_inode(struct task_struct *task, struct inode *inode)
1996{
1997 task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
1998
1999 inode->i_mode &= ~(S_ISUID | S_ISGID);
2000 security_task_to_inode(task, inode);
2001}
2002
2003/*
2004 * Rewrite the inode's ownerships here because the owning task may have
2005 * performed a setuid(), etc.
2006 *
2007 */
2008static int pid_revalidate(struct dentry *dentry, unsigned int flags)
2009{
2010 struct inode *inode;
2011 struct task_struct *task;
2012 int ret = 0;
2013
2014 rcu_read_lock();
2015 inode = d_inode_rcu(dentry);
2016 if (!inode)
2017 goto out;
2018 task = pid_task(proc_pid(inode), PIDTYPE_PID);
2019
2020 if (task) {
2021 pid_update_inode(task, inode);
2022 ret = 1;
2023 }
2024out:
2025 rcu_read_unlock();
2026 return ret;
2027}
2028
2029static inline bool proc_inode_is_dead(struct inode *inode)
2030{
2031 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
2032}
2033
2034int pid_delete_dentry(const struct dentry *dentry)
2035{
2036 /* Is the task we represent dead?
2037 * If so, then don't put the dentry on the lru list,
2038 * kill it immediately.
2039 */
2040 return proc_inode_is_dead(d_inode(dentry));
2041}
2042
2043const struct dentry_operations pid_dentry_operations =
2044{
2045 .d_revalidate = pid_revalidate,
2046 .d_delete = pid_delete_dentry,
2047};
2048
2049/* Lookups */
2050
2051/*
2052 * Fill a directory entry.
2053 *
2054 * If possible create the dcache entry and derive our inode number and
2055 * file type from dcache entry.
2056 *
2057 * Since all of the proc inode numbers are dynamically generated, the inode
2058 * numbers do not exist until the inode is cache. This means creating
2059 * the dcache entry in readdir is necessary to keep the inode numbers
2060 * reported by readdir in sync with the inode numbers reported
2061 * by stat.
2062 */
2063bool proc_fill_cache(struct file *file, struct dir_context *ctx,
2064 const char *name, unsigned int len,
2065 instantiate_t instantiate, struct task_struct *task, const void *ptr)
2066{
2067 struct dentry *child, *dir = file->f_path.dentry;
2068 struct qstr qname = QSTR_INIT(name, len);
2069 struct inode *inode;
2070 unsigned type = DT_UNKNOWN;
2071 ino_t ino = 1;
2072
2073 child = d_hash_and_lookup(dir, &qname);
2074 if (!child) {
2075 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
2076 child = d_alloc_parallel(dir, &qname, &wq);
2077 if (IS_ERR(child))
2078 goto end_instantiate;
2079 if (d_in_lookup(child)) {
2080 struct dentry *res;
2081 res = instantiate(child, task, ptr);
2082 d_lookup_done(child);
2083 if (unlikely(res)) {
2084 dput(child);
2085 child = res;
2086 if (IS_ERR(child))
2087 goto end_instantiate;
2088 }
2089 }
2090 }
2091 inode = d_inode(child);
2092 ino = inode->i_ino;
2093 type = inode->i_mode >> 12;
2094 dput(child);
2095end_instantiate:
2096 return dir_emit(ctx, name, len, ino, type);
2097}
2098
2099/*
2100 * dname_to_vma_addr - maps a dentry name into two unsigned longs
2101 * which represent vma start and end addresses.
2102 */
2103static int dname_to_vma_addr(struct dentry *dentry,
2104 unsigned long *start, unsigned long *end)
2105{
2106 const char *str = dentry->d_name.name;
2107 unsigned long long sval, eval;
2108 unsigned int len;
2109
2110 if (str[0] == '0' && str[1] != '-')
2111 return -EINVAL;
2112 len = _parse_integer(str, 16, &sval);
2113 if (len & KSTRTOX_OVERFLOW)
2114 return -EINVAL;
2115 if (sval != (unsigned long)sval)
2116 return -EINVAL;
2117 str += len;
2118
2119 if (*str != '-')
2120 return -EINVAL;
2121 str++;
2122
2123 if (str[0] == '0' && str[1])
2124 return -EINVAL;
2125 len = _parse_integer(str, 16, &eval);
2126 if (len & KSTRTOX_OVERFLOW)
2127 return -EINVAL;
2128 if (eval != (unsigned long)eval)
2129 return -EINVAL;
2130 str += len;
2131
2132 if (*str != '\0')
2133 return -EINVAL;
2134
2135 *start = sval;
2136 *end = eval;
2137
2138 return 0;
2139}
2140
2141static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
2142{
2143 unsigned long vm_start, vm_end;
2144 bool exact_vma_exists = false;
2145 struct mm_struct *mm = NULL;
2146 struct task_struct *task;
2147 struct inode *inode;
2148 int status = 0;
2149
2150 if (flags & LOOKUP_RCU)
2151 return -ECHILD;
2152
2153 inode = d_inode(dentry);
2154 task = get_proc_task(inode);
2155 if (!task)
2156 goto out_notask;
2157
2158 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
2159 if (IS_ERR_OR_NULL(mm))
2160 goto out;
2161
2162 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2163 status = mmap_read_lock_killable(mm);
2164 if (!status) {
2165 exact_vma_exists = !!find_exact_vma(mm, vm_start,
2166 vm_end);
2167 mmap_read_unlock(mm);
2168 }
2169 }
2170
2171 mmput(mm);
2172
2173 if (exact_vma_exists) {
2174 task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
2175
2176 security_task_to_inode(task, inode);
2177 status = 1;
2178 }
2179
2180out:
2181 put_task_struct(task);
2182
2183out_notask:
2184 return status;
2185}
2186
2187static const struct dentry_operations tid_map_files_dentry_operations = {
2188 .d_revalidate = map_files_d_revalidate,
2189 .d_delete = pid_delete_dentry,
2190};
2191
2192static int map_files_get_link(struct dentry *dentry, struct path *path)
2193{
2194 unsigned long vm_start, vm_end;
2195 struct vm_area_struct *vma;
2196 struct task_struct *task;
2197 struct mm_struct *mm;
2198 int rc;
2199
2200 rc = -ENOENT;
2201 task = get_proc_task(d_inode(dentry));
2202 if (!task)
2203 goto out;
2204
2205 mm = get_task_mm(task);
2206 put_task_struct(task);
2207 if (!mm)
2208 goto out;
2209
2210 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2211 if (rc)
2212 goto out_mmput;
2213
2214 rc = mmap_read_lock_killable(mm);
2215 if (rc)
2216 goto out_mmput;
2217
2218 rc = -ENOENT;
2219 vma = find_exact_vma(mm, vm_start, vm_end);
2220 if (vma && vma->vm_file) {
2221 *path = vma->vm_file->f_path;
2222 path_get(path);
2223 rc = 0;
2224 }
2225 mmap_read_unlock(mm);
2226
2227out_mmput:
2228 mmput(mm);
2229out:
2230 return rc;
2231}
2232
2233struct map_files_info {
2234 unsigned long start;
2235 unsigned long end;
2236 fmode_t mode;
2237};
2238
2239/*
2240 * Only allow CAP_SYS_ADMIN and CAP_CHECKPOINT_RESTORE to follow the links, due
2241 * to concerns about how the symlinks may be used to bypass permissions on
2242 * ancestor directories in the path to the file in question.
2243 */
2244static const char *
2245proc_map_files_get_link(struct dentry *dentry,
2246 struct inode *inode,
2247 struct delayed_call *done)
2248{
2249 if (!checkpoint_restore_ns_capable(&init_user_ns))
2250 return ERR_PTR(-EPERM);
2251
2252 return proc_pid_get_link(dentry, inode, done);
2253}
2254
2255/*
2256 * Identical to proc_pid_link_inode_operations except for get_link()
2257 */
2258static const struct inode_operations proc_map_files_link_inode_operations = {
2259 .readlink = proc_pid_readlink,
2260 .get_link = proc_map_files_get_link,
2261 .setattr = proc_setattr,
2262};
2263
2264static struct dentry *
2265proc_map_files_instantiate(struct dentry *dentry,
2266 struct task_struct *task, const void *ptr)
2267{
2268 fmode_t mode = (fmode_t)(unsigned long)ptr;
2269 struct proc_inode *ei;
2270 struct inode *inode;
2271
2272 inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK |
2273 ((mode & FMODE_READ ) ? S_IRUSR : 0) |
2274 ((mode & FMODE_WRITE) ? S_IWUSR : 0));
2275 if (!inode)
2276 return ERR_PTR(-ENOENT);
2277
2278 ei = PROC_I(inode);
2279 ei->op.proc_get_link = map_files_get_link;
2280
2281 inode->i_op = &proc_map_files_link_inode_operations;
2282 inode->i_size = 64;
2283
2284 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2285 return d_splice_alias(inode, dentry);
2286}
2287
2288static struct dentry *proc_map_files_lookup(struct inode *dir,
2289 struct dentry *dentry, unsigned int flags)
2290{
2291 unsigned long vm_start, vm_end;
2292 struct vm_area_struct *vma;
2293 struct task_struct *task;
2294 struct dentry *result;
2295 struct mm_struct *mm;
2296
2297 result = ERR_PTR(-ENOENT);
2298 task = get_proc_task(dir);
2299 if (!task)
2300 goto out;
2301
2302 result = ERR_PTR(-EACCES);
2303 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2304 goto out_put_task;
2305
2306 result = ERR_PTR(-ENOENT);
2307 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2308 goto out_put_task;
2309
2310 mm = get_task_mm(task);
2311 if (!mm)
2312 goto out_put_task;
2313
2314 result = ERR_PTR(-EINTR);
2315 if (mmap_read_lock_killable(mm))
2316 goto out_put_mm;
2317
2318 result = ERR_PTR(-ENOENT);
2319 vma = find_exact_vma(mm, vm_start, vm_end);
2320 if (!vma)
2321 goto out_no_vma;
2322
2323 if (vma->vm_file)
2324 result = proc_map_files_instantiate(dentry, task,
2325 (void *)(unsigned long)vma->vm_file->f_mode);
2326
2327out_no_vma:
2328 mmap_read_unlock(mm);
2329out_put_mm:
2330 mmput(mm);
2331out_put_task:
2332 put_task_struct(task);
2333out:
2334 return result;
2335}
2336
2337static const struct inode_operations proc_map_files_inode_operations = {
2338 .lookup = proc_map_files_lookup,
2339 .permission = proc_fd_permission,
2340 .setattr = proc_setattr,
2341};
2342
2343static int
2344proc_map_files_readdir(struct file *file, struct dir_context *ctx)
2345{
2346 struct vm_area_struct *vma;
2347 struct task_struct *task;
2348 struct mm_struct *mm;
2349 unsigned long nr_files, pos, i;
2350 GENRADIX(struct map_files_info) fa;
2351 struct map_files_info *p;
2352 int ret;
2353 struct vma_iterator vmi;
2354
2355 genradix_init(&fa);
2356
2357 ret = -ENOENT;
2358 task = get_proc_task(file_inode(file));
2359 if (!task)
2360 goto out;
2361
2362 ret = -EACCES;
2363 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2364 goto out_put_task;
2365
2366 ret = 0;
2367 if (!dir_emit_dots(file, ctx))
2368 goto out_put_task;
2369
2370 mm = get_task_mm(task);
2371 if (!mm)
2372 goto out_put_task;
2373
2374 ret = mmap_read_lock_killable(mm);
2375 if (ret) {
2376 mmput(mm);
2377 goto out_put_task;
2378 }
2379
2380 nr_files = 0;
2381
2382 /*
2383 * We need two passes here:
2384 *
2385 * 1) Collect vmas of mapped files with mmap_lock taken
2386 * 2) Release mmap_lock and instantiate entries
2387 *
2388 * otherwise we get lockdep complained, since filldir()
2389 * routine might require mmap_lock taken in might_fault().
2390 */
2391
2392 pos = 2;
2393 vma_iter_init(&vmi, mm, 0);
2394 for_each_vma(vmi, vma) {
2395 if (!vma->vm_file)
2396 continue;
2397 if (++pos <= ctx->pos)
2398 continue;
2399
2400 p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL);
2401 if (!p) {
2402 ret = -ENOMEM;
2403 mmap_read_unlock(mm);
2404 mmput(mm);
2405 goto out_put_task;
2406 }
2407
2408 p->start = vma->vm_start;
2409 p->end = vma->vm_end;
2410 p->mode = vma->vm_file->f_mode;
2411 }
2412 mmap_read_unlock(mm);
2413 mmput(mm);
2414
2415 for (i = 0; i < nr_files; i++) {
2416 char buf[4 * sizeof(long) + 2]; /* max: %lx-%lx\0 */
2417 unsigned int len;
2418
2419 p = genradix_ptr(&fa, i);
2420 len = snprintf(buf, sizeof(buf), "%lx-%lx", p->start, p->end);
2421 if (!proc_fill_cache(file, ctx,
2422 buf, len,
2423 proc_map_files_instantiate,
2424 task,
2425 (void *)(unsigned long)p->mode))
2426 break;
2427 ctx->pos++;
2428 }
2429
2430out_put_task:
2431 put_task_struct(task);
2432out:
2433 genradix_free(&fa);
2434 return ret;
2435}
2436
2437static const struct file_operations proc_map_files_operations = {
2438 .read = generic_read_dir,
2439 .iterate_shared = proc_map_files_readdir,
2440 .llseek = generic_file_llseek,
2441};
2442
2443#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
2444struct timers_private {
2445 struct pid *pid;
2446 struct task_struct *task;
2447 struct sighand_struct *sighand;
2448 struct pid_namespace *ns;
2449 unsigned long flags;
2450};
2451
2452static void *timers_start(struct seq_file *m, loff_t *pos)
2453{
2454 struct timers_private *tp = m->private;
2455
2456 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2457 if (!tp->task)
2458 return ERR_PTR(-ESRCH);
2459
2460 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2461 if (!tp->sighand)
2462 return ERR_PTR(-ESRCH);
2463
2464 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2465}
2466
2467static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2468{
2469 struct timers_private *tp = m->private;
2470 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2471}
2472
2473static void timers_stop(struct seq_file *m, void *v)
2474{
2475 struct timers_private *tp = m->private;
2476
2477 if (tp->sighand) {
2478 unlock_task_sighand(tp->task, &tp->flags);
2479 tp->sighand = NULL;
2480 }
2481
2482 if (tp->task) {
2483 put_task_struct(tp->task);
2484 tp->task = NULL;
2485 }
2486}
2487
2488static int show_timer(struct seq_file *m, void *v)
2489{
2490 struct k_itimer *timer;
2491 struct timers_private *tp = m->private;
2492 int notify;
2493 static const char * const nstr[] = {
2494 [SIGEV_SIGNAL] = "signal",
2495 [SIGEV_NONE] = "none",
2496 [SIGEV_THREAD] = "thread",
2497 };
2498
2499 timer = list_entry((struct list_head *)v, struct k_itimer, list);
2500 notify = timer->it_sigev_notify;
2501
2502 seq_printf(m, "ID: %d\n", timer->it_id);
2503 seq_printf(m, "signal: %d/%px\n",
2504 timer->sigq->info.si_signo,
2505 timer->sigq->info.si_value.sival_ptr);
2506 seq_printf(m, "notify: %s/%s.%d\n",
2507 nstr[notify & ~SIGEV_THREAD_ID],
2508 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2509 pid_nr_ns(timer->it_pid, tp->ns));
2510 seq_printf(m, "ClockID: %d\n", timer->it_clock);
2511
2512 return 0;
2513}
2514
2515static const struct seq_operations proc_timers_seq_ops = {
2516 .start = timers_start,
2517 .next = timers_next,
2518 .stop = timers_stop,
2519 .show = show_timer,
2520};
2521
2522static int proc_timers_open(struct inode *inode, struct file *file)
2523{
2524 struct timers_private *tp;
2525
2526 tp = __seq_open_private(file, &proc_timers_seq_ops,
2527 sizeof(struct timers_private));
2528 if (!tp)
2529 return -ENOMEM;
2530
2531 tp->pid = proc_pid(inode);
2532 tp->ns = proc_pid_ns(inode->i_sb);
2533 return 0;
2534}
2535
2536static const struct file_operations proc_timers_operations = {
2537 .open = proc_timers_open,
2538 .read = seq_read,
2539 .llseek = seq_lseek,
2540 .release = seq_release_private,
2541};
2542#endif
2543
2544static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2545 size_t count, loff_t *offset)
2546{
2547 struct inode *inode = file_inode(file);
2548 struct task_struct *p;
2549 u64 slack_ns;
2550 int err;
2551
2552 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2553 if (err < 0)
2554 return err;
2555
2556 p = get_proc_task(inode);
2557 if (!p)
2558 return -ESRCH;
2559
2560 if (p != current) {
2561 rcu_read_lock();
2562 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
2563 rcu_read_unlock();
2564 count = -EPERM;
2565 goto out;
2566 }
2567 rcu_read_unlock();
2568
2569 err = security_task_setscheduler(p);
2570 if (err) {
2571 count = err;
2572 goto out;
2573 }
2574 }
2575
2576 task_lock(p);
2577 if (slack_ns == 0)
2578 p->timer_slack_ns = p->default_timer_slack_ns;
2579 else
2580 p->timer_slack_ns = slack_ns;
2581 task_unlock(p);
2582
2583out:
2584 put_task_struct(p);
2585
2586 return count;
2587}
2588
2589static int timerslack_ns_show(struct seq_file *m, void *v)
2590{
2591 struct inode *inode = m->private;
2592 struct task_struct *p;
2593 int err = 0;
2594
2595 p = get_proc_task(inode);
2596 if (!p)
2597 return -ESRCH;
2598
2599 if (p != current) {
2600 rcu_read_lock();
2601 if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
2602 rcu_read_unlock();
2603 err = -EPERM;
2604 goto out;
2605 }
2606 rcu_read_unlock();
2607
2608 err = security_task_getscheduler(p);
2609 if (err)
2610 goto out;
2611 }
2612
2613 task_lock(p);
2614 seq_printf(m, "%llu\n", p->timer_slack_ns);
2615 task_unlock(p);
2616
2617out:
2618 put_task_struct(p);
2619
2620 return err;
2621}
2622
2623static int timerslack_ns_open(struct inode *inode, struct file *filp)
2624{
2625 return single_open(filp, timerslack_ns_show, inode);
2626}
2627
2628static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2629 .open = timerslack_ns_open,
2630 .read = seq_read,
2631 .write = timerslack_ns_write,
2632 .llseek = seq_lseek,
2633 .release = single_release,
2634};
2635
2636static struct dentry *proc_pident_instantiate(struct dentry *dentry,
2637 struct task_struct *task, const void *ptr)
2638{
2639 const struct pid_entry *p = ptr;
2640 struct inode *inode;
2641 struct proc_inode *ei;
2642
2643 inode = proc_pid_make_inode(dentry->d_sb, task, p->mode);
2644 if (!inode)
2645 return ERR_PTR(-ENOENT);
2646
2647 ei = PROC_I(inode);
2648 if (S_ISDIR(inode->i_mode))
2649 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2650 if (p->iop)
2651 inode->i_op = p->iop;
2652 if (p->fop)
2653 inode->i_fop = p->fop;
2654 ei->op = p->op;
2655 pid_update_inode(task, inode);
2656 d_set_d_op(dentry, &pid_dentry_operations);
2657 return d_splice_alias(inode, dentry);
2658}
2659
2660static struct dentry *proc_pident_lookup(struct inode *dir,
2661 struct dentry *dentry,
2662 const struct pid_entry *p,
2663 const struct pid_entry *end)
2664{
2665 struct task_struct *task = get_proc_task(dir);
2666 struct dentry *res = ERR_PTR(-ENOENT);
2667
2668 if (!task)
2669 goto out_no_task;
2670
2671 /*
2672 * Yes, it does not scale. And it should not. Don't add
2673 * new entries into /proc/<tgid>/ without very good reasons.
2674 */
2675 for (; p < end; p++) {
2676 if (p->len != dentry->d_name.len)
2677 continue;
2678 if (!memcmp(dentry->d_name.name, p->name, p->len)) {
2679 res = proc_pident_instantiate(dentry, task, p);
2680 break;
2681 }
2682 }
2683 put_task_struct(task);
2684out_no_task:
2685 return res;
2686}
2687
2688static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
2689 const struct pid_entry *ents, unsigned int nents)
2690{
2691 struct task_struct *task = get_proc_task(file_inode(file));
2692 const struct pid_entry *p;
2693
2694 if (!task)
2695 return -ENOENT;
2696
2697 if (!dir_emit_dots(file, ctx))
2698 goto out;
2699
2700 if (ctx->pos >= nents + 2)
2701 goto out;
2702
2703 for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
2704 if (!proc_fill_cache(file, ctx, p->name, p->len,
2705 proc_pident_instantiate, task, p))
2706 break;
2707 ctx->pos++;
2708 }
2709out:
2710 put_task_struct(task);
2711 return 0;
2712}
2713
2714#ifdef CONFIG_SECURITY
2715static int proc_pid_attr_open(struct inode *inode, struct file *file)
2716{
2717 file->private_data = NULL;
2718 __mem_open(inode, file, PTRACE_MODE_READ_FSCREDS);
2719 return 0;
2720}
2721
2722static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2723 size_t count, loff_t *ppos)
2724{
2725 struct inode * inode = file_inode(file);
2726 char *p = NULL;
2727 ssize_t length;
2728 struct task_struct *task = get_proc_task(inode);
2729
2730 if (!task)
2731 return -ESRCH;
2732
2733 length = security_getprocattr(task, PROC_I(inode)->op.lsm,
2734 file->f_path.dentry->d_name.name,
2735 &p);
2736 put_task_struct(task);
2737 if (length > 0)
2738 length = simple_read_from_buffer(buf, count, ppos, p, length);
2739 kfree(p);
2740 return length;
2741}
2742
2743static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2744 size_t count, loff_t *ppos)
2745{
2746 struct inode * inode = file_inode(file);
2747 struct task_struct *task;
2748 void *page;
2749 int rv;
2750
2751 /* A task may only write when it was the opener. */
2752 if (file->private_data != current->mm)
2753 return -EPERM;
2754
2755 rcu_read_lock();
2756 task = pid_task(proc_pid(inode), PIDTYPE_PID);
2757 if (!task) {
2758 rcu_read_unlock();
2759 return -ESRCH;
2760 }
2761 /* A task may only write its own attributes. */
2762 if (current != task) {
2763 rcu_read_unlock();
2764 return -EACCES;
2765 }
2766 /* Prevent changes to overridden credentials. */
2767 if (current_cred() != current_real_cred()) {
2768 rcu_read_unlock();
2769 return -EBUSY;
2770 }
2771 rcu_read_unlock();
2772
2773 if (count > PAGE_SIZE)
2774 count = PAGE_SIZE;
2775
2776 /* No partial writes. */
2777 if (*ppos != 0)
2778 return -EINVAL;
2779
2780 page = memdup_user(buf, count);
2781 if (IS_ERR(page)) {
2782 rv = PTR_ERR(page);
2783 goto out;
2784 }
2785
2786 /* Guard against adverse ptrace interaction */
2787 rv = mutex_lock_interruptible(¤t->signal->cred_guard_mutex);
2788 if (rv < 0)
2789 goto out_free;
2790
2791 rv = security_setprocattr(PROC_I(inode)->op.lsm,
2792 file->f_path.dentry->d_name.name, page,
2793 count);
2794 mutex_unlock(¤t->signal->cred_guard_mutex);
2795out_free:
2796 kfree(page);
2797out:
2798 return rv;
2799}
2800
2801static const struct file_operations proc_pid_attr_operations = {
2802 .open = proc_pid_attr_open,
2803 .read = proc_pid_attr_read,
2804 .write = proc_pid_attr_write,
2805 .llseek = generic_file_llseek,
2806 .release = mem_release,
2807};
2808
2809#define LSM_DIR_OPS(LSM) \
2810static int proc_##LSM##_attr_dir_iterate(struct file *filp, \
2811 struct dir_context *ctx) \
2812{ \
2813 return proc_pident_readdir(filp, ctx, \
2814 LSM##_attr_dir_stuff, \
2815 ARRAY_SIZE(LSM##_attr_dir_stuff)); \
2816} \
2817\
2818static const struct file_operations proc_##LSM##_attr_dir_ops = { \
2819 .read = generic_read_dir, \
2820 .iterate = proc_##LSM##_attr_dir_iterate, \
2821 .llseek = default_llseek, \
2822}; \
2823\
2824static struct dentry *proc_##LSM##_attr_dir_lookup(struct inode *dir, \
2825 struct dentry *dentry, unsigned int flags) \
2826{ \
2827 return proc_pident_lookup(dir, dentry, \
2828 LSM##_attr_dir_stuff, \
2829 LSM##_attr_dir_stuff + ARRAY_SIZE(LSM##_attr_dir_stuff)); \
2830} \
2831\
2832static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \
2833 .lookup = proc_##LSM##_attr_dir_lookup, \
2834 .getattr = pid_getattr, \
2835 .setattr = proc_setattr, \
2836}
2837
2838#ifdef CONFIG_SECURITY_SMACK
2839static const struct pid_entry smack_attr_dir_stuff[] = {
2840 ATTR("smack", "current", 0666),
2841};
2842LSM_DIR_OPS(smack);
2843#endif
2844
2845#ifdef CONFIG_SECURITY_APPARMOR
2846static const struct pid_entry apparmor_attr_dir_stuff[] = {
2847 ATTR("apparmor", "current", 0666),
2848 ATTR("apparmor", "prev", 0444),
2849 ATTR("apparmor", "exec", 0666),
2850};
2851LSM_DIR_OPS(apparmor);
2852#endif
2853
2854static const struct pid_entry attr_dir_stuff[] = {
2855 ATTR(NULL, "current", 0666),
2856 ATTR(NULL, "prev", 0444),
2857 ATTR(NULL, "exec", 0666),
2858 ATTR(NULL, "fscreate", 0666),
2859 ATTR(NULL, "keycreate", 0666),
2860 ATTR(NULL, "sockcreate", 0666),
2861#ifdef CONFIG_SECURITY_SMACK
2862 DIR("smack", 0555,
2863 proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
2864#endif
2865#ifdef CONFIG_SECURITY_APPARMOR
2866 DIR("apparmor", 0555,
2867 proc_apparmor_attr_dir_inode_ops, proc_apparmor_attr_dir_ops),
2868#endif
2869};
2870
2871static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
2872{
2873 return proc_pident_readdir(file, ctx,
2874 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2875}
2876
2877static const struct file_operations proc_attr_dir_operations = {
2878 .read = generic_read_dir,
2879 .iterate_shared = proc_attr_dir_readdir,
2880 .llseek = generic_file_llseek,
2881};
2882
2883static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2884 struct dentry *dentry, unsigned int flags)
2885{
2886 return proc_pident_lookup(dir, dentry,
2887 attr_dir_stuff,
2888 attr_dir_stuff + ARRAY_SIZE(attr_dir_stuff));
2889}
2890
2891static const struct inode_operations proc_attr_dir_inode_operations = {
2892 .lookup = proc_attr_dir_lookup,
2893 .getattr = pid_getattr,
2894 .setattr = proc_setattr,
2895};
2896
2897#endif
2898
2899#ifdef CONFIG_ELF_CORE
2900static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2901 size_t count, loff_t *ppos)
2902{
2903 struct task_struct *task = get_proc_task(file_inode(file));
2904 struct mm_struct *mm;
2905 char buffer[PROC_NUMBUF];
2906 size_t len;
2907 int ret;
2908
2909 if (!task)
2910 return -ESRCH;
2911
2912 ret = 0;
2913 mm = get_task_mm(task);
2914 if (mm) {
2915 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2916 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2917 MMF_DUMP_FILTER_SHIFT));
2918 mmput(mm);
2919 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2920 }
2921
2922 put_task_struct(task);
2923
2924 return ret;
2925}
2926
2927static ssize_t proc_coredump_filter_write(struct file *file,
2928 const char __user *buf,
2929 size_t count,
2930 loff_t *ppos)
2931{
2932 struct task_struct *task;
2933 struct mm_struct *mm;
2934 unsigned int val;
2935 int ret;
2936 int i;
2937 unsigned long mask;
2938
2939 ret = kstrtouint_from_user(buf, count, 0, &val);
2940 if (ret < 0)
2941 return ret;
2942
2943 ret = -ESRCH;
2944 task = get_proc_task(file_inode(file));
2945 if (!task)
2946 goto out_no_task;
2947
2948 mm = get_task_mm(task);
2949 if (!mm)
2950 goto out_no_mm;
2951 ret = 0;
2952
2953 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2954 if (val & mask)
2955 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2956 else
2957 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2958 }
2959
2960 mmput(mm);
2961 out_no_mm:
2962 put_task_struct(task);
2963 out_no_task:
2964 if (ret < 0)
2965 return ret;
2966 return count;
2967}
2968
2969static const struct file_operations proc_coredump_filter_operations = {
2970 .read = proc_coredump_filter_read,
2971 .write = proc_coredump_filter_write,
2972 .llseek = generic_file_llseek,
2973};
2974#endif
2975
2976#ifdef CONFIG_TASK_IO_ACCOUNTING
2977static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
2978{
2979 struct task_io_accounting acct = task->ioac;
2980 unsigned long flags;
2981 int result;
2982
2983 result = down_read_killable(&task->signal->exec_update_lock);
2984 if (result)
2985 return result;
2986
2987 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
2988 result = -EACCES;
2989 goto out_unlock;
2990 }
2991
2992 if (whole && lock_task_sighand(task, &flags)) {
2993 struct task_struct *t = task;
2994
2995 task_io_accounting_add(&acct, &task->signal->ioac);
2996 while_each_thread(task, t)
2997 task_io_accounting_add(&acct, &t->ioac);
2998
2999 unlock_task_sighand(task, &flags);
3000 }
3001 seq_printf(m,
3002 "rchar: %llu\n"
3003 "wchar: %llu\n"
3004 "syscr: %llu\n"
3005 "syscw: %llu\n"
3006 "read_bytes: %llu\n"
3007 "write_bytes: %llu\n"
3008 "cancelled_write_bytes: %llu\n",
3009 (unsigned long long)acct.rchar,
3010 (unsigned long long)acct.wchar,
3011 (unsigned long long)acct.syscr,
3012 (unsigned long long)acct.syscw,
3013 (unsigned long long)acct.read_bytes,
3014 (unsigned long long)acct.write_bytes,
3015 (unsigned long long)acct.cancelled_write_bytes);
3016 result = 0;
3017
3018out_unlock:
3019 up_read(&task->signal->exec_update_lock);
3020 return result;
3021}
3022
3023static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
3024 struct pid *pid, struct task_struct *task)
3025{
3026 return do_io_accounting(task, m, 0);
3027}
3028
3029static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
3030 struct pid *pid, struct task_struct *task)
3031{
3032 return do_io_accounting(task, m, 1);
3033}
3034#endif /* CONFIG_TASK_IO_ACCOUNTING */
3035
3036#ifdef CONFIG_USER_NS
3037static int proc_id_map_open(struct inode *inode, struct file *file,
3038 const struct seq_operations *seq_ops)
3039{
3040 struct user_namespace *ns = NULL;
3041 struct task_struct *task;
3042 struct seq_file *seq;
3043 int ret = -EINVAL;
3044
3045 task = get_proc_task(inode);
3046 if (task) {
3047 rcu_read_lock();
3048 ns = get_user_ns(task_cred_xxx(task, user_ns));
3049 rcu_read_unlock();
3050 put_task_struct(task);
3051 }
3052 if (!ns)
3053 goto err;
3054
3055 ret = seq_open(file, seq_ops);
3056 if (ret)
3057 goto err_put_ns;
3058
3059 seq = file->private_data;
3060 seq->private = ns;
3061
3062 return 0;
3063err_put_ns:
3064 put_user_ns(ns);
3065err:
3066 return ret;
3067}
3068
3069static int proc_id_map_release(struct inode *inode, struct file *file)
3070{
3071 struct seq_file *seq = file->private_data;
3072 struct user_namespace *ns = seq->private;
3073 put_user_ns(ns);
3074 return seq_release(inode, file);
3075}
3076
3077static int proc_uid_map_open(struct inode *inode, struct file *file)
3078{
3079 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
3080}
3081
3082static int proc_gid_map_open(struct inode *inode, struct file *file)
3083{
3084 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
3085}
3086
3087static int proc_projid_map_open(struct inode *inode, struct file *file)
3088{
3089 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
3090}
3091
3092static const struct file_operations proc_uid_map_operations = {
3093 .open = proc_uid_map_open,
3094 .write = proc_uid_map_write,
3095 .read = seq_read,
3096 .llseek = seq_lseek,
3097 .release = proc_id_map_release,
3098};
3099
3100static const struct file_operations proc_gid_map_operations = {
3101 .open = proc_gid_map_open,
3102 .write = proc_gid_map_write,
3103 .read = seq_read,
3104 .llseek = seq_lseek,
3105 .release = proc_id_map_release,
3106};
3107
3108static const struct file_operations proc_projid_map_operations = {
3109 .open = proc_projid_map_open,
3110 .write = proc_projid_map_write,
3111 .read = seq_read,
3112 .llseek = seq_lseek,
3113 .release = proc_id_map_release,
3114};
3115
3116static int proc_setgroups_open(struct inode *inode, struct file *file)
3117{
3118 struct user_namespace *ns = NULL;
3119 struct task_struct *task;
3120 int ret;
3121
3122 ret = -ESRCH;
3123 task = get_proc_task(inode);
3124 if (task) {
3125 rcu_read_lock();
3126 ns = get_user_ns(task_cred_xxx(task, user_ns));
3127 rcu_read_unlock();
3128 put_task_struct(task);
3129 }
3130 if (!ns)
3131 goto err;
3132
3133 if (file->f_mode & FMODE_WRITE) {
3134 ret = -EACCES;
3135 if (!ns_capable(ns, CAP_SYS_ADMIN))
3136 goto err_put_ns;
3137 }
3138
3139 ret = single_open(file, &proc_setgroups_show, ns);
3140 if (ret)
3141 goto err_put_ns;
3142
3143 return 0;
3144err_put_ns:
3145 put_user_ns(ns);
3146err:
3147 return ret;
3148}
3149
3150static int proc_setgroups_release(struct inode *inode, struct file *file)
3151{
3152 struct seq_file *seq = file->private_data;
3153 struct user_namespace *ns = seq->private;
3154 int ret = single_release(inode, file);
3155 put_user_ns(ns);
3156 return ret;
3157}
3158
3159static const struct file_operations proc_setgroups_operations = {
3160 .open = proc_setgroups_open,
3161 .write = proc_setgroups_write,
3162 .read = seq_read,
3163 .llseek = seq_lseek,
3164 .release = proc_setgroups_release,
3165};
3166#endif /* CONFIG_USER_NS */
3167
3168static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
3169 struct pid *pid, struct task_struct *task)
3170{
3171 int err = lock_trace(task);
3172 if (!err) {
3173 seq_printf(m, "%08x\n", task->personality);
3174 unlock_trace(task);
3175 }
3176 return err;
3177}
3178
3179#ifdef CONFIG_LIVEPATCH
3180static int proc_pid_patch_state(struct seq_file *m, struct pid_namespace *ns,
3181 struct pid *pid, struct task_struct *task)
3182{
3183 seq_printf(m, "%d\n", task->patch_state);
3184 return 0;
3185}
3186#endif /* CONFIG_LIVEPATCH */
3187
3188#ifdef CONFIG_KSM
3189static int proc_pid_ksm_merging_pages(struct seq_file *m, struct pid_namespace *ns,
3190 struct pid *pid, struct task_struct *task)
3191{
3192 struct mm_struct *mm;
3193
3194 mm = get_task_mm(task);
3195 if (mm) {
3196 seq_printf(m, "%lu\n", mm->ksm_merging_pages);
3197 mmput(mm);
3198 }
3199
3200 return 0;
3201}
3202static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns,
3203 struct pid *pid, struct task_struct *task)
3204{
3205 struct mm_struct *mm;
3206
3207 mm = get_task_mm(task);
3208 if (mm) {
3209 seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items);
3210 mmput(mm);
3211 }
3212
3213 return 0;
3214}
3215#endif /* CONFIG_KSM */
3216
3217#ifdef CONFIG_STACKLEAK_METRICS
3218static int proc_stack_depth(struct seq_file *m, struct pid_namespace *ns,
3219 struct pid *pid, struct task_struct *task)
3220{
3221 unsigned long prev_depth = THREAD_SIZE -
3222 (task->prev_lowest_stack & (THREAD_SIZE - 1));
3223 unsigned long depth = THREAD_SIZE -
3224 (task->lowest_stack & (THREAD_SIZE - 1));
3225
3226 seq_printf(m, "previous stack depth: %lu\nstack depth: %lu\n",
3227 prev_depth, depth);
3228 return 0;
3229}
3230#endif /* CONFIG_STACKLEAK_METRICS */
3231
3232/*
3233 * Thread groups
3234 */
3235static const struct file_operations proc_task_operations;
3236static const struct inode_operations proc_task_inode_operations;
3237
3238static const struct pid_entry tgid_base_stuff[] = {
3239 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
3240 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3241 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
3242 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3243 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3244#ifdef CONFIG_NET
3245 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3246#endif
3247 REG("environ", S_IRUSR, proc_environ_operations),
3248 REG("auxv", S_IRUSR, proc_auxv_operations),
3249 ONE("status", S_IRUGO, proc_pid_status),
3250 ONE("personality", S_IRUSR, proc_pid_personality),
3251 ONE("limits", S_IRUGO, proc_pid_limits),
3252#ifdef CONFIG_SCHED_DEBUG
3253 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3254#endif
3255#ifdef CONFIG_SCHED_AUTOGROUP
3256 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
3257#endif
3258#ifdef CONFIG_TIME_NS
3259 REG("timens_offsets", S_IRUGO|S_IWUSR, proc_timens_offsets_operations),
3260#endif
3261 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3262#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3263 ONE("syscall", S_IRUSR, proc_pid_syscall),
3264#endif
3265 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3266 ONE("stat", S_IRUGO, proc_tgid_stat),
3267 ONE("statm", S_IRUGO, proc_pid_statm),
3268 REG("maps", S_IRUGO, proc_pid_maps_operations),
3269#ifdef CONFIG_NUMA
3270 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
3271#endif
3272 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3273 LNK("cwd", proc_cwd_link),
3274 LNK("root", proc_root_link),
3275 LNK("exe", proc_exe_link),
3276 REG("mounts", S_IRUGO, proc_mounts_operations),
3277 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3278 REG("mountstats", S_IRUSR, proc_mountstats_operations),
3279#ifdef CONFIG_PROC_PAGE_MONITOR
3280 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3281 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
3282 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3283 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3284#endif
3285#ifdef CONFIG_SECURITY
3286 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3287#endif
3288#ifdef CONFIG_KALLSYMS
3289 ONE("wchan", S_IRUGO, proc_pid_wchan),
3290#endif
3291#ifdef CONFIG_STACKTRACE
3292 ONE("stack", S_IRUSR, proc_pid_stack),
3293#endif
3294#ifdef CONFIG_SCHED_INFO
3295 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3296#endif
3297#ifdef CONFIG_LATENCYTOP
3298 REG("latency", S_IRUGO, proc_lstats_operations),
3299#endif
3300#ifdef CONFIG_PROC_PID_CPUSET
3301 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3302#endif
3303#ifdef CONFIG_CGROUPS
3304 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3305#endif
3306#ifdef CONFIG_PROC_CPU_RESCTRL
3307 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),
3308#endif
3309 ONE("oom_score", S_IRUGO, proc_oom_score),
3310 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3311 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3312#ifdef CONFIG_AUDIT
3313 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3314 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3315#endif
3316#ifdef CONFIG_FAULT_INJECTION
3317 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3318 REG("fail-nth", 0644, proc_fail_nth_operations),
3319#endif
3320#ifdef CONFIG_ELF_CORE
3321 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3322#endif
3323#ifdef CONFIG_TASK_IO_ACCOUNTING
3324 ONE("io", S_IRUSR, proc_tgid_io_accounting),
3325#endif
3326#ifdef CONFIG_USER_NS
3327 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3328 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3329 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3330 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3331#endif
3332#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
3333 REG("timers", S_IRUGO, proc_timers_operations),
3334#endif
3335 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
3336#ifdef CONFIG_LIVEPATCH
3337 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3338#endif
3339#ifdef CONFIG_STACKLEAK_METRICS
3340 ONE("stack_depth", S_IRUGO, proc_stack_depth),
3341#endif
3342#ifdef CONFIG_PROC_PID_ARCH_STATUS
3343 ONE("arch_status", S_IRUGO, proc_pid_arch_status),
3344#endif
3345#ifdef CONFIG_SECCOMP_CACHE_DEBUG
3346 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),
3347#endif
3348#ifdef CONFIG_KSM
3349 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages),
3350 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat),
3351#endif
3352};
3353
3354static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
3355{
3356 return proc_pident_readdir(file, ctx,
3357 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3358}
3359
3360static const struct file_operations proc_tgid_base_operations = {
3361 .read = generic_read_dir,
3362 .iterate_shared = proc_tgid_base_readdir,
3363 .llseek = generic_file_llseek,
3364};
3365
3366struct pid *tgid_pidfd_to_pid(const struct file *file)
3367{
3368 if (file->f_op != &proc_tgid_base_operations)
3369 return ERR_PTR(-EBADF);
3370
3371 return proc_pid(file_inode(file));
3372}
3373
3374static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3375{
3376 return proc_pident_lookup(dir, dentry,
3377 tgid_base_stuff,
3378 tgid_base_stuff + ARRAY_SIZE(tgid_base_stuff));
3379}
3380
3381static const struct inode_operations proc_tgid_base_inode_operations = {
3382 .lookup = proc_tgid_base_lookup,
3383 .getattr = pid_getattr,
3384 .setattr = proc_setattr,
3385 .permission = proc_pid_permission,
3386};
3387
3388/**
3389 * proc_flush_pid - Remove dcache entries for @pid from the /proc dcache.
3390 * @pid: pid that should be flushed.
3391 *
3392 * This function walks a list of inodes (that belong to any proc
3393 * filesystem) that are attached to the pid and flushes them from
3394 * the dentry cache.
3395 *
3396 * It is safe and reasonable to cache /proc entries for a task until
3397 * that task exits. After that they just clog up the dcache with
3398 * useless entries, possibly causing useful dcache entries to be
3399 * flushed instead. This routine is provided to flush those useless
3400 * dcache entries when a process is reaped.
3401 *
3402 * NOTE: This routine is just an optimization so it does not guarantee
3403 * that no dcache entries will exist after a process is reaped
3404 * it just makes it very unlikely that any will persist.
3405 */
3406
3407void proc_flush_pid(struct pid *pid)
3408{
3409 proc_invalidate_siblings_dcache(&pid->inodes, &pid->lock);
3410}
3411
3412static struct dentry *proc_pid_instantiate(struct dentry * dentry,
3413 struct task_struct *task, const void *ptr)
3414{
3415 struct inode *inode;
3416
3417 inode = proc_pid_make_base_inode(dentry->d_sb, task,
3418 S_IFDIR | S_IRUGO | S_IXUGO);
3419 if (!inode)
3420 return ERR_PTR(-ENOENT);
3421
3422 inode->i_op = &proc_tgid_base_inode_operations;
3423 inode->i_fop = &proc_tgid_base_operations;
3424 inode->i_flags|=S_IMMUTABLE;
3425
3426 set_nlink(inode, nlink_tgid);
3427 pid_update_inode(task, inode);
3428
3429 d_set_d_op(dentry, &pid_dentry_operations);
3430 return d_splice_alias(inode, dentry);
3431}
3432
3433struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags)
3434{
3435 struct task_struct *task;
3436 unsigned tgid;
3437 struct proc_fs_info *fs_info;
3438 struct pid_namespace *ns;
3439 struct dentry *result = ERR_PTR(-ENOENT);
3440
3441 tgid = name_to_int(&dentry->d_name);
3442 if (tgid == ~0U)
3443 goto out;
3444
3445 fs_info = proc_sb_info(dentry->d_sb);
3446 ns = fs_info->pid_ns;
3447 rcu_read_lock();
3448 task = find_task_by_pid_ns(tgid, ns);
3449 if (task)
3450 get_task_struct(task);
3451 rcu_read_unlock();
3452 if (!task)
3453 goto out;
3454
3455 /* Limit procfs to only ptraceable tasks */
3456 if (fs_info->hide_pid == HIDEPID_NOT_PTRACEABLE) {
3457 if (!has_pid_permissions(fs_info, task, HIDEPID_NO_ACCESS))
3458 goto out_put_task;
3459 }
3460
3461 result = proc_pid_instantiate(dentry, task, NULL);
3462out_put_task:
3463 put_task_struct(task);
3464out:
3465 return result;
3466}
3467
3468/*
3469 * Find the first task with tgid >= tgid
3470 *
3471 */
3472struct tgid_iter {
3473 unsigned int tgid;
3474 struct task_struct *task;
3475};
3476static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3477{
3478 struct pid *pid;
3479
3480 if (iter.task)
3481 put_task_struct(iter.task);
3482 rcu_read_lock();
3483retry:
3484 iter.task = NULL;
3485 pid = find_ge_pid(iter.tgid, ns);
3486 if (pid) {
3487 iter.tgid = pid_nr_ns(pid, ns);
3488 iter.task = pid_task(pid, PIDTYPE_TGID);
3489 if (!iter.task) {
3490 iter.tgid += 1;
3491 goto retry;
3492 }
3493 get_task_struct(iter.task);
3494 }
3495 rcu_read_unlock();
3496 return iter;
3497}
3498
3499#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
3500
3501/* for the /proc/ directory itself, after non-process stuff has been done */
3502int proc_pid_readdir(struct file *file, struct dir_context *ctx)
3503{
3504 struct tgid_iter iter;
3505 struct proc_fs_info *fs_info = proc_sb_info(file_inode(file)->i_sb);
3506 struct pid_namespace *ns = proc_pid_ns(file_inode(file)->i_sb);
3507 loff_t pos = ctx->pos;
3508
3509 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
3510 return 0;
3511
3512 if (pos == TGID_OFFSET - 2) {
3513 struct inode *inode = d_inode(fs_info->proc_self);
3514 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
3515 return 0;
3516 ctx->pos = pos = pos + 1;
3517 }
3518 if (pos == TGID_OFFSET - 1) {
3519 struct inode *inode = d_inode(fs_info->proc_thread_self);
3520 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3521 return 0;
3522 ctx->pos = pos = pos + 1;
3523 }
3524 iter.tgid = pos - TGID_OFFSET;
3525 iter.task = NULL;
3526 for (iter = next_tgid(ns, iter);
3527 iter.task;
3528 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3529 char name[10 + 1];
3530 unsigned int len;
3531
3532 cond_resched();
3533 if (!has_pid_permissions(fs_info, iter.task, HIDEPID_INVISIBLE))
3534 continue;
3535
3536 len = snprintf(name, sizeof(name), "%u", iter.tgid);
3537 ctx->pos = iter.tgid + TGID_OFFSET;
3538 if (!proc_fill_cache(file, ctx, name, len,
3539 proc_pid_instantiate, iter.task, NULL)) {
3540 put_task_struct(iter.task);
3541 return 0;
3542 }
3543 }
3544 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
3545 return 0;
3546}
3547
3548/*
3549 * proc_tid_comm_permission is a special permission function exclusively
3550 * used for the node /proc/<pid>/task/<tid>/comm.
3551 * It bypasses generic permission checks in the case where a task of the same
3552 * task group attempts to access the node.
3553 * The rationale behind this is that glibc and bionic access this node for
3554 * cross thread naming (pthread_set/getname_np(!self)). However, if
3555 * PR_SET_DUMPABLE gets set to 0 this node among others becomes uid=0 gid=0,
3556 * which locks out the cross thread naming implementation.
3557 * This function makes sure that the node is always accessible for members of
3558 * same thread group.
3559 */
3560static int proc_tid_comm_permission(struct user_namespace *mnt_userns,
3561 struct inode *inode, int mask)
3562{
3563 bool is_same_tgroup;
3564 struct task_struct *task;
3565
3566 task = get_proc_task(inode);
3567 if (!task)
3568 return -ESRCH;
3569 is_same_tgroup = same_thread_group(current, task);
3570 put_task_struct(task);
3571
3572 if (likely(is_same_tgroup && !(mask & MAY_EXEC))) {
3573 /* This file (/proc/<pid>/task/<tid>/comm) can always be
3574 * read or written by the members of the corresponding
3575 * thread group.
3576 */
3577 return 0;
3578 }
3579
3580 return generic_permission(&init_user_ns, inode, mask);
3581}
3582
3583static const struct inode_operations proc_tid_comm_inode_operations = {
3584 .permission = proc_tid_comm_permission,
3585};
3586
3587/*
3588 * Tasks
3589 */
3590static const struct pid_entry tid_base_stuff[] = {
3591 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3592 DIR("fdinfo", S_IRUGO|S_IXUGO, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3593 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3594#ifdef CONFIG_NET
3595 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3596#endif
3597 REG("environ", S_IRUSR, proc_environ_operations),
3598 REG("auxv", S_IRUSR, proc_auxv_operations),
3599 ONE("status", S_IRUGO, proc_pid_status),
3600 ONE("personality", S_IRUSR, proc_pid_personality),
3601 ONE("limits", S_IRUGO, proc_pid_limits),
3602#ifdef CONFIG_SCHED_DEBUG
3603 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3604#endif
3605 NOD("comm", S_IFREG|S_IRUGO|S_IWUSR,
3606 &proc_tid_comm_inode_operations,
3607 &proc_pid_set_comm_operations, {}),
3608#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3609 ONE("syscall", S_IRUSR, proc_pid_syscall),
3610#endif
3611 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3612 ONE("stat", S_IRUGO, proc_tid_stat),
3613 ONE("statm", S_IRUGO, proc_pid_statm),
3614 REG("maps", S_IRUGO, proc_pid_maps_operations),
3615#ifdef CONFIG_PROC_CHILDREN
3616 REG("children", S_IRUGO, proc_tid_children_operations),
3617#endif
3618#ifdef CONFIG_NUMA
3619 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
3620#endif
3621 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3622 LNK("cwd", proc_cwd_link),
3623 LNK("root", proc_root_link),
3624 LNK("exe", proc_exe_link),
3625 REG("mounts", S_IRUGO, proc_mounts_operations),
3626 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3627#ifdef CONFIG_PROC_PAGE_MONITOR
3628 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3629 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
3630 REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
3631 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3632#endif
3633#ifdef CONFIG_SECURITY
3634 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3635#endif
3636#ifdef CONFIG_KALLSYMS
3637 ONE("wchan", S_IRUGO, proc_pid_wchan),
3638#endif
3639#ifdef CONFIG_STACKTRACE
3640 ONE("stack", S_IRUSR, proc_pid_stack),
3641#endif
3642#ifdef CONFIG_SCHED_INFO
3643 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3644#endif
3645#ifdef CONFIG_LATENCYTOP
3646 REG("latency", S_IRUGO, proc_lstats_operations),
3647#endif
3648#ifdef CONFIG_PROC_PID_CPUSET
3649 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3650#endif
3651#ifdef CONFIG_CGROUPS
3652 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3653#endif
3654#ifdef CONFIG_PROC_CPU_RESCTRL
3655 ONE("cpu_resctrl_groups", S_IRUGO, proc_resctrl_show),
3656#endif
3657 ONE("oom_score", S_IRUGO, proc_oom_score),
3658 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3659 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3660#ifdef CONFIG_AUDIT
3661 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3662 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3663#endif
3664#ifdef CONFIG_FAULT_INJECTION
3665 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3666 REG("fail-nth", 0644, proc_fail_nth_operations),
3667#endif
3668#ifdef CONFIG_TASK_IO_ACCOUNTING
3669 ONE("io", S_IRUSR, proc_tid_io_accounting),
3670#endif
3671#ifdef CONFIG_USER_NS
3672 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3673 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3674 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3675 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3676#endif
3677#ifdef CONFIG_LIVEPATCH
3678 ONE("patch_state", S_IRUSR, proc_pid_patch_state),
3679#endif
3680#ifdef CONFIG_PROC_PID_ARCH_STATUS
3681 ONE("arch_status", S_IRUGO, proc_pid_arch_status),
3682#endif
3683#ifdef CONFIG_SECCOMP_CACHE_DEBUG
3684 ONE("seccomp_cache", S_IRUSR, proc_pid_seccomp_cache),
3685#endif
3686#ifdef CONFIG_KSM
3687 ONE("ksm_merging_pages", S_IRUSR, proc_pid_ksm_merging_pages),
3688 ONE("ksm_stat", S_IRUSR, proc_pid_ksm_stat),
3689#endif
3690};
3691
3692static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
3693{
3694 return proc_pident_readdir(file, ctx,
3695 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3696}
3697
3698static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3699{
3700 return proc_pident_lookup(dir, dentry,
3701 tid_base_stuff,
3702 tid_base_stuff + ARRAY_SIZE(tid_base_stuff));
3703}
3704
3705static const struct file_operations proc_tid_base_operations = {
3706 .read = generic_read_dir,
3707 .iterate_shared = proc_tid_base_readdir,
3708 .llseek = generic_file_llseek,
3709};
3710
3711static const struct inode_operations proc_tid_base_inode_operations = {
3712 .lookup = proc_tid_base_lookup,
3713 .getattr = pid_getattr,
3714 .setattr = proc_setattr,
3715};
3716
3717static struct dentry *proc_task_instantiate(struct dentry *dentry,
3718 struct task_struct *task, const void *ptr)
3719{
3720 struct inode *inode;
3721 inode = proc_pid_make_base_inode(dentry->d_sb, task,
3722 S_IFDIR | S_IRUGO | S_IXUGO);
3723 if (!inode)
3724 return ERR_PTR(-ENOENT);
3725
3726 inode->i_op = &proc_tid_base_inode_operations;
3727 inode->i_fop = &proc_tid_base_operations;
3728 inode->i_flags |= S_IMMUTABLE;
3729
3730 set_nlink(inode, nlink_tid);
3731 pid_update_inode(task, inode);
3732
3733 d_set_d_op(dentry, &pid_dentry_operations);
3734 return d_splice_alias(inode, dentry);
3735}
3736
3737static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3738{
3739 struct task_struct *task;
3740 struct task_struct *leader = get_proc_task(dir);
3741 unsigned tid;
3742 struct proc_fs_info *fs_info;
3743 struct pid_namespace *ns;
3744 struct dentry *result = ERR_PTR(-ENOENT);
3745
3746 if (!leader)
3747 goto out_no_task;
3748
3749 tid = name_to_int(&dentry->d_name);
3750 if (tid == ~0U)
3751 goto out;
3752
3753 fs_info = proc_sb_info(dentry->d_sb);
3754 ns = fs_info->pid_ns;
3755 rcu_read_lock();
3756 task = find_task_by_pid_ns(tid, ns);
3757 if (task)
3758 get_task_struct(task);
3759 rcu_read_unlock();
3760 if (!task)
3761 goto out;
3762 if (!same_thread_group(leader, task))
3763 goto out_drop_task;
3764
3765 result = proc_task_instantiate(dentry, task, NULL);
3766out_drop_task:
3767 put_task_struct(task);
3768out:
3769 put_task_struct(leader);
3770out_no_task:
3771 return result;
3772}
3773
3774/*
3775 * Find the first tid of a thread group to return to user space.
3776 *
3777 * Usually this is just the thread group leader, but if the users
3778 * buffer was too small or there was a seek into the middle of the
3779 * directory we have more work todo.
3780 *
3781 * In the case of a short read we start with find_task_by_pid.
3782 *
3783 * In the case of a seek we start with the leader and walk nr
3784 * threads past it.
3785 */
3786static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3787 struct pid_namespace *ns)
3788{
3789 struct task_struct *pos, *task;
3790 unsigned long nr = f_pos;
3791
3792 if (nr != f_pos) /* 32bit overflow? */
3793 return NULL;
3794
3795 rcu_read_lock();
3796 task = pid_task(pid, PIDTYPE_PID);
3797 if (!task)
3798 goto fail;
3799
3800 /* Attempt to start with the tid of a thread */
3801 if (tid && nr) {
3802 pos = find_task_by_pid_ns(tid, ns);
3803 if (pos && same_thread_group(pos, task))
3804 goto found;
3805 }
3806
3807 /* If nr exceeds the number of threads there is nothing todo */
3808 if (nr >= get_nr_threads(task))
3809 goto fail;
3810
3811 /* If we haven't found our starting place yet start
3812 * with the leader and walk nr threads forward.
3813 */
3814 pos = task = task->group_leader;
3815 do {
3816 if (!nr--)
3817 goto found;
3818 } while_each_thread(task, pos);
3819fail:
3820 pos = NULL;
3821 goto out;
3822found:
3823 get_task_struct(pos);
3824out:
3825 rcu_read_unlock();
3826 return pos;
3827}
3828
3829/*
3830 * Find the next thread in the thread list.
3831 * Return NULL if there is an error or no next thread.
3832 *
3833 * The reference to the input task_struct is released.
3834 */
3835static struct task_struct *next_tid(struct task_struct *start)
3836{
3837 struct task_struct *pos = NULL;
3838 rcu_read_lock();
3839 if (pid_alive(start)) {
3840 pos = next_thread(start);
3841 if (thread_group_leader(pos))
3842 pos = NULL;
3843 else
3844 get_task_struct(pos);
3845 }
3846 rcu_read_unlock();
3847 put_task_struct(start);
3848 return pos;
3849}
3850
3851/* for the /proc/TGID/task/ directories */
3852static int proc_task_readdir(struct file *file, struct dir_context *ctx)
3853{
3854 struct inode *inode = file_inode(file);
3855 struct task_struct *task;
3856 struct pid_namespace *ns;
3857 int tid;
3858
3859 if (proc_inode_is_dead(inode))
3860 return -ENOENT;
3861
3862 if (!dir_emit_dots(file, ctx))
3863 return 0;
3864
3865 /* f_version caches the tgid value that the last readdir call couldn't
3866 * return. lseek aka telldir automagically resets f_version to 0.
3867 */
3868 ns = proc_pid_ns(inode->i_sb);
3869 tid = (int)file->f_version;
3870 file->f_version = 0;
3871 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
3872 task;
3873 task = next_tid(task), ctx->pos++) {
3874 char name[10 + 1];
3875 unsigned int len;
3876
3877 tid = task_pid_nr_ns(task, ns);
3878 if (!tid)
3879 continue; /* The task has just exited. */
3880 len = snprintf(name, sizeof(name), "%u", tid);
3881 if (!proc_fill_cache(file, ctx, name, len,
3882 proc_task_instantiate, task, NULL)) {
3883 /* returning this tgid failed, save it as the first
3884 * pid for the next readir call */
3885 file->f_version = (u64)tid;
3886 put_task_struct(task);
3887 break;
3888 }
3889 }
3890
3891 return 0;
3892}
3893
3894static int proc_task_getattr(struct user_namespace *mnt_userns,
3895 const struct path *path, struct kstat *stat,
3896 u32 request_mask, unsigned int query_flags)
3897{
3898 struct inode *inode = d_inode(path->dentry);
3899 struct task_struct *p = get_proc_task(inode);
3900 generic_fillattr(&init_user_ns, inode, stat);
3901
3902 if (p) {
3903 stat->nlink += get_nr_threads(p);
3904 put_task_struct(p);
3905 }
3906
3907 return 0;
3908}
3909
3910static const struct inode_operations proc_task_inode_operations = {
3911 .lookup = proc_task_lookup,
3912 .getattr = proc_task_getattr,
3913 .setattr = proc_setattr,
3914 .permission = proc_pid_permission,
3915};
3916
3917static const struct file_operations proc_task_operations = {
3918 .read = generic_read_dir,
3919 .iterate_shared = proc_task_readdir,
3920 .llseek = generic_file_llseek,
3921};
3922
3923void __init set_proc_pid_nlink(void)
3924{
3925 nlink_tid = pid_entry_nlink(tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3926 nlink_tgid = pid_entry_nlink(tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3927}
1/*
2 * linux/fs/proc/base.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * proc base directory handling functions
7 *
8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
9 * Instead of using magical inumbers to determine the kind of object
10 * we allocate and fill in-core inodes upon lookup. They don't even
11 * go into icache. We cache the reference to task_struct upon lookup too.
12 * Eventually it should become a filesystem in its own. We don't use the
13 * rest of procfs anymore.
14 *
15 *
16 * Changelog:
17 * 17-Jan-2005
18 * Allan Bezerra
19 * Bruna Moreira <bruna.moreira@indt.org.br>
20 * Edjard Mota <edjard.mota@indt.org.br>
21 * Ilias Biris <ilias.biris@indt.org.br>
22 * Mauricio Lin <mauricio.lin@indt.org.br>
23 *
24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
25 *
26 * A new process specific entry (smaps) included in /proc. It shows the
27 * size of rss for each memory area. The maps entry lacks information
28 * about physical memory size (rss) for each mapped file, i.e.,
29 * rss information for executables and library files.
30 * This additional information is useful for any tools that need to know
31 * about physical memory consumption for a process specific library.
32 *
33 * Changelog:
34 * 21-Feb-2005
35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
36 * Pud inclusion in the page table walking.
37 *
38 * ChangeLog:
39 * 10-Mar-2005
40 * 10LE Instituto Nokia de Tecnologia - INdT:
41 * A better way to walks through the page table as suggested by Hugh Dickins.
42 *
43 * Simo Piiroinen <simo.piiroinen@nokia.com>:
44 * Smaps information related to shared, private, clean and dirty pages.
45 *
46 * Paul Mundt <paul.mundt@nokia.com>:
47 * Overall revision about smaps.
48 */
49
50#include <asm/uaccess.h>
51
52#include <linux/errno.h>
53#include <linux/time.h>
54#include <linux/proc_fs.h>
55#include <linux/stat.h>
56#include <linux/task_io_accounting_ops.h>
57#include <linux/init.h>
58#include <linux/capability.h>
59#include <linux/file.h>
60#include <linux/fdtable.h>
61#include <linux/string.h>
62#include <linux/seq_file.h>
63#include <linux/namei.h>
64#include <linux/mnt_namespace.h>
65#include <linux/mm.h>
66#include <linux/swap.h>
67#include <linux/rcupdate.h>
68#include <linux/kallsyms.h>
69#include <linux/stacktrace.h>
70#include <linux/resource.h>
71#include <linux/module.h>
72#include <linux/mount.h>
73#include <linux/security.h>
74#include <linux/ptrace.h>
75#include <linux/tracehook.h>
76#include <linux/cgroup.h>
77#include <linux/cpuset.h>
78#include <linux/audit.h>
79#include <linux/poll.h>
80#include <linux/nsproxy.h>
81#include <linux/oom.h>
82#include <linux/elf.h>
83#include <linux/pid_namespace.h>
84#include <linux/user_namespace.h>
85#include <linux/fs_struct.h>
86#include <linux/slab.h>
87#include <linux/flex_array.h>
88#ifdef CONFIG_HARDWALL
89#include <asm/hardwall.h>
90#endif
91#include <trace/events/oom.h>
92#include "internal.h"
93
94/* NOTE:
95 * Implementing inode permission operations in /proc is almost
96 * certainly an error. Permission checks need to happen during
97 * each system call not at open time. The reason is that most of
98 * what we wish to check for permissions in /proc varies at runtime.
99 *
100 * The classic example of a problem is opening file descriptors
101 * in /proc for a task before it execs a suid executable.
102 */
103
104struct pid_entry {
105 char *name;
106 int len;
107 umode_t mode;
108 const struct inode_operations *iop;
109 const struct file_operations *fop;
110 union proc_op op;
111};
112
113#define NOD(NAME, MODE, IOP, FOP, OP) { \
114 .name = (NAME), \
115 .len = sizeof(NAME) - 1, \
116 .mode = MODE, \
117 .iop = IOP, \
118 .fop = FOP, \
119 .op = OP, \
120}
121
122#define DIR(NAME, MODE, iops, fops) \
123 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
124#define LNK(NAME, get_link) \
125 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
126 &proc_pid_link_inode_operations, NULL, \
127 { .proc_get_link = get_link } )
128#define REG(NAME, MODE, fops) \
129 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
130#define INF(NAME, MODE, read) \
131 NOD(NAME, (S_IFREG|(MODE)), \
132 NULL, &proc_info_file_operations, \
133 { .proc_read = read } )
134#define ONE(NAME, MODE, show) \
135 NOD(NAME, (S_IFREG|(MODE)), \
136 NULL, &proc_single_file_operations, \
137 { .proc_show = show } )
138
139static int proc_fd_permission(struct inode *inode, int mask);
140
141/*
142 * Count the number of hardlinks for the pid_entry table, excluding the .
143 * and .. links.
144 */
145static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
146 unsigned int n)
147{
148 unsigned int i;
149 unsigned int count;
150
151 count = 0;
152 for (i = 0; i < n; ++i) {
153 if (S_ISDIR(entries[i].mode))
154 ++count;
155 }
156
157 return count;
158}
159
160static int get_task_root(struct task_struct *task, struct path *root)
161{
162 int result = -ENOENT;
163
164 task_lock(task);
165 if (task->fs) {
166 get_fs_root(task->fs, root);
167 result = 0;
168 }
169 task_unlock(task);
170 return result;
171}
172
173static int proc_cwd_link(struct dentry *dentry, struct path *path)
174{
175 struct task_struct *task = get_proc_task(dentry->d_inode);
176 int result = -ENOENT;
177
178 if (task) {
179 task_lock(task);
180 if (task->fs) {
181 get_fs_pwd(task->fs, path);
182 result = 0;
183 }
184 task_unlock(task);
185 put_task_struct(task);
186 }
187 return result;
188}
189
190static int proc_root_link(struct dentry *dentry, struct path *path)
191{
192 struct task_struct *task = get_proc_task(dentry->d_inode);
193 int result = -ENOENT;
194
195 if (task) {
196 result = get_task_root(task, path);
197 put_task_struct(task);
198 }
199 return result;
200}
201
202static int proc_pid_cmdline(struct task_struct *task, char * buffer)
203{
204 int res = 0;
205 unsigned int len;
206 struct mm_struct *mm = get_task_mm(task);
207 if (!mm)
208 goto out;
209 if (!mm->arg_end)
210 goto out_mm; /* Shh! No looking before we're done */
211
212 len = mm->arg_end - mm->arg_start;
213
214 if (len > PAGE_SIZE)
215 len = PAGE_SIZE;
216
217 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
218
219 // If the nul at the end of args has been overwritten, then
220 // assume application is using setproctitle(3).
221 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
222 len = strnlen(buffer, res);
223 if (len < res) {
224 res = len;
225 } else {
226 len = mm->env_end - mm->env_start;
227 if (len > PAGE_SIZE - res)
228 len = PAGE_SIZE - res;
229 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
230 res = strnlen(buffer, res);
231 }
232 }
233out_mm:
234 mmput(mm);
235out:
236 return res;
237}
238
239static int proc_pid_auxv(struct task_struct *task, char *buffer)
240{
241 struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ);
242 int res = PTR_ERR(mm);
243 if (mm && !IS_ERR(mm)) {
244 unsigned int nwords = 0;
245 do {
246 nwords += 2;
247 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
248 res = nwords * sizeof(mm->saved_auxv[0]);
249 if (res > PAGE_SIZE)
250 res = PAGE_SIZE;
251 memcpy(buffer, mm->saved_auxv, res);
252 mmput(mm);
253 }
254 return res;
255}
256
257
258#ifdef CONFIG_KALLSYMS
259/*
260 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
261 * Returns the resolved symbol. If that fails, simply return the address.
262 */
263static int proc_pid_wchan(struct task_struct *task, char *buffer)
264{
265 unsigned long wchan;
266 char symname[KSYM_NAME_LEN];
267
268 wchan = get_wchan(task);
269
270 if (lookup_symbol_name(wchan, symname) < 0)
271 if (!ptrace_may_access(task, PTRACE_MODE_READ))
272 return 0;
273 else
274 return sprintf(buffer, "%lu", wchan);
275 else
276 return sprintf(buffer, "%s", symname);
277}
278#endif /* CONFIG_KALLSYMS */
279
280static int lock_trace(struct task_struct *task)
281{
282 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
283 if (err)
284 return err;
285 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
286 mutex_unlock(&task->signal->cred_guard_mutex);
287 return -EPERM;
288 }
289 return 0;
290}
291
292static void unlock_trace(struct task_struct *task)
293{
294 mutex_unlock(&task->signal->cred_guard_mutex);
295}
296
297#ifdef CONFIG_STACKTRACE
298
299#define MAX_STACK_TRACE_DEPTH 64
300
301static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
302 struct pid *pid, struct task_struct *task)
303{
304 struct stack_trace trace;
305 unsigned long *entries;
306 int err;
307 int i;
308
309 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
310 if (!entries)
311 return -ENOMEM;
312
313 trace.nr_entries = 0;
314 trace.max_entries = MAX_STACK_TRACE_DEPTH;
315 trace.entries = entries;
316 trace.skip = 0;
317
318 err = lock_trace(task);
319 if (!err) {
320 save_stack_trace_tsk(task, &trace);
321
322 for (i = 0; i < trace.nr_entries; i++) {
323 seq_printf(m, "[<%pK>] %pS\n",
324 (void *)entries[i], (void *)entries[i]);
325 }
326 unlock_trace(task);
327 }
328 kfree(entries);
329
330 return err;
331}
332#endif
333
334#ifdef CONFIG_SCHEDSTATS
335/*
336 * Provides /proc/PID/schedstat
337 */
338static int proc_pid_schedstat(struct task_struct *task, char *buffer)
339{
340 return sprintf(buffer, "%llu %llu %lu\n",
341 (unsigned long long)task->se.sum_exec_runtime,
342 (unsigned long long)task->sched_info.run_delay,
343 task->sched_info.pcount);
344}
345#endif
346
347#ifdef CONFIG_LATENCYTOP
348static int lstats_show_proc(struct seq_file *m, void *v)
349{
350 int i;
351 struct inode *inode = m->private;
352 struct task_struct *task = get_proc_task(inode);
353
354 if (!task)
355 return -ESRCH;
356 seq_puts(m, "Latency Top version : v0.1\n");
357 for (i = 0; i < 32; i++) {
358 struct latency_record *lr = &task->latency_record[i];
359 if (lr->backtrace[0]) {
360 int q;
361 seq_printf(m, "%i %li %li",
362 lr->count, lr->time, lr->max);
363 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
364 unsigned long bt = lr->backtrace[q];
365 if (!bt)
366 break;
367 if (bt == ULONG_MAX)
368 break;
369 seq_printf(m, " %ps", (void *)bt);
370 }
371 seq_putc(m, '\n');
372 }
373
374 }
375 put_task_struct(task);
376 return 0;
377}
378
379static int lstats_open(struct inode *inode, struct file *file)
380{
381 return single_open(file, lstats_show_proc, inode);
382}
383
384static ssize_t lstats_write(struct file *file, const char __user *buf,
385 size_t count, loff_t *offs)
386{
387 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
388
389 if (!task)
390 return -ESRCH;
391 clear_all_latency_tracing(task);
392 put_task_struct(task);
393
394 return count;
395}
396
397static const struct file_operations proc_lstats_operations = {
398 .open = lstats_open,
399 .read = seq_read,
400 .write = lstats_write,
401 .llseek = seq_lseek,
402 .release = single_release,
403};
404
405#endif
406
407static int proc_oom_score(struct task_struct *task, char *buffer)
408{
409 unsigned long totalpages = totalram_pages + total_swap_pages;
410 unsigned long points = 0;
411
412 read_lock(&tasklist_lock);
413 if (pid_alive(task))
414 points = oom_badness(task, NULL, NULL, totalpages) *
415 1000 / totalpages;
416 read_unlock(&tasklist_lock);
417 return sprintf(buffer, "%lu\n", points);
418}
419
420struct limit_names {
421 char *name;
422 char *unit;
423};
424
425static const struct limit_names lnames[RLIM_NLIMITS] = {
426 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
427 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
428 [RLIMIT_DATA] = {"Max data size", "bytes"},
429 [RLIMIT_STACK] = {"Max stack size", "bytes"},
430 [RLIMIT_CORE] = {"Max core file size", "bytes"},
431 [RLIMIT_RSS] = {"Max resident set", "bytes"},
432 [RLIMIT_NPROC] = {"Max processes", "processes"},
433 [RLIMIT_NOFILE] = {"Max open files", "files"},
434 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
435 [RLIMIT_AS] = {"Max address space", "bytes"},
436 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
437 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
438 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
439 [RLIMIT_NICE] = {"Max nice priority", NULL},
440 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
441 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
442};
443
444/* Display limits for a process */
445static int proc_pid_limits(struct task_struct *task, char *buffer)
446{
447 unsigned int i;
448 int count = 0;
449 unsigned long flags;
450 char *bufptr = buffer;
451
452 struct rlimit rlim[RLIM_NLIMITS];
453
454 if (!lock_task_sighand(task, &flags))
455 return 0;
456 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
457 unlock_task_sighand(task, &flags);
458
459 /*
460 * print the file header
461 */
462 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
463 "Limit", "Soft Limit", "Hard Limit", "Units");
464
465 for (i = 0; i < RLIM_NLIMITS; i++) {
466 if (rlim[i].rlim_cur == RLIM_INFINITY)
467 count += sprintf(&bufptr[count], "%-25s %-20s ",
468 lnames[i].name, "unlimited");
469 else
470 count += sprintf(&bufptr[count], "%-25s %-20lu ",
471 lnames[i].name, rlim[i].rlim_cur);
472
473 if (rlim[i].rlim_max == RLIM_INFINITY)
474 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
475 else
476 count += sprintf(&bufptr[count], "%-20lu ",
477 rlim[i].rlim_max);
478
479 if (lnames[i].unit)
480 count += sprintf(&bufptr[count], "%-10s\n",
481 lnames[i].unit);
482 else
483 count += sprintf(&bufptr[count], "\n");
484 }
485
486 return count;
487}
488
489#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
490static int proc_pid_syscall(struct task_struct *task, char *buffer)
491{
492 long nr;
493 unsigned long args[6], sp, pc;
494 int res = lock_trace(task);
495 if (res)
496 return res;
497
498 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
499 res = sprintf(buffer, "running\n");
500 else if (nr < 0)
501 res = sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
502 else
503 res = sprintf(buffer,
504 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
505 nr,
506 args[0], args[1], args[2], args[3], args[4], args[5],
507 sp, pc);
508 unlock_trace(task);
509 return res;
510}
511#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
512
513/************************************************************************/
514/* Here the fs part begins */
515/************************************************************************/
516
517/* permission checks */
518static int proc_fd_access_allowed(struct inode *inode)
519{
520 struct task_struct *task;
521 int allowed = 0;
522 /* Allow access to a task's file descriptors if it is us or we
523 * may use ptrace attach to the process and find out that
524 * information.
525 */
526 task = get_proc_task(inode);
527 if (task) {
528 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
529 put_task_struct(task);
530 }
531 return allowed;
532}
533
534int proc_setattr(struct dentry *dentry, struct iattr *attr)
535{
536 int error;
537 struct inode *inode = dentry->d_inode;
538
539 if (attr->ia_valid & ATTR_MODE)
540 return -EPERM;
541
542 error = inode_change_ok(inode, attr);
543 if (error)
544 return error;
545
546 if ((attr->ia_valid & ATTR_SIZE) &&
547 attr->ia_size != i_size_read(inode)) {
548 error = vmtruncate(inode, attr->ia_size);
549 if (error)
550 return error;
551 }
552
553 setattr_copy(inode, attr);
554 mark_inode_dirty(inode);
555 return 0;
556}
557
558/*
559 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
560 * or euid/egid (for hide_pid_min=2)?
561 */
562static bool has_pid_permissions(struct pid_namespace *pid,
563 struct task_struct *task,
564 int hide_pid_min)
565{
566 if (pid->hide_pid < hide_pid_min)
567 return true;
568 if (in_group_p(pid->pid_gid))
569 return true;
570 return ptrace_may_access(task, PTRACE_MODE_READ);
571}
572
573
574static int proc_pid_permission(struct inode *inode, int mask)
575{
576 struct pid_namespace *pid = inode->i_sb->s_fs_info;
577 struct task_struct *task;
578 bool has_perms;
579
580 task = get_proc_task(inode);
581 if (!task)
582 return -ESRCH;
583 has_perms = has_pid_permissions(pid, task, 1);
584 put_task_struct(task);
585
586 if (!has_perms) {
587 if (pid->hide_pid == 2) {
588 /*
589 * Let's make getdents(), stat(), and open()
590 * consistent with each other. If a process
591 * may not stat() a file, it shouldn't be seen
592 * in procfs at all.
593 */
594 return -ENOENT;
595 }
596
597 return -EPERM;
598 }
599 return generic_permission(inode, mask);
600}
601
602
603
604static const struct inode_operations proc_def_inode_operations = {
605 .setattr = proc_setattr,
606};
607
608#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
609
610static ssize_t proc_info_read(struct file * file, char __user * buf,
611 size_t count, loff_t *ppos)
612{
613 struct inode * inode = file->f_path.dentry->d_inode;
614 unsigned long page;
615 ssize_t length;
616 struct task_struct *task = get_proc_task(inode);
617
618 length = -ESRCH;
619 if (!task)
620 goto out_no_task;
621
622 if (count > PROC_BLOCK_SIZE)
623 count = PROC_BLOCK_SIZE;
624
625 length = -ENOMEM;
626 if (!(page = __get_free_page(GFP_TEMPORARY)))
627 goto out;
628
629 length = PROC_I(inode)->op.proc_read(task, (char*)page);
630
631 if (length >= 0)
632 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
633 free_page(page);
634out:
635 put_task_struct(task);
636out_no_task:
637 return length;
638}
639
640static const struct file_operations proc_info_file_operations = {
641 .read = proc_info_read,
642 .llseek = generic_file_llseek,
643};
644
645static int proc_single_show(struct seq_file *m, void *v)
646{
647 struct inode *inode = m->private;
648 struct pid_namespace *ns;
649 struct pid *pid;
650 struct task_struct *task;
651 int ret;
652
653 ns = inode->i_sb->s_fs_info;
654 pid = proc_pid(inode);
655 task = get_pid_task(pid, PIDTYPE_PID);
656 if (!task)
657 return -ESRCH;
658
659 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
660
661 put_task_struct(task);
662 return ret;
663}
664
665static int proc_single_open(struct inode *inode, struct file *filp)
666{
667 return single_open(filp, proc_single_show, inode);
668}
669
670static const struct file_operations proc_single_file_operations = {
671 .open = proc_single_open,
672 .read = seq_read,
673 .llseek = seq_lseek,
674 .release = single_release,
675};
676
677static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
678{
679 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
680 struct mm_struct *mm;
681
682 if (!task)
683 return -ESRCH;
684
685 mm = mm_access(task, mode);
686 put_task_struct(task);
687
688 if (IS_ERR(mm))
689 return PTR_ERR(mm);
690
691 if (mm) {
692 /* ensure this mm_struct can't be freed */
693 atomic_inc(&mm->mm_count);
694 /* but do not pin its memory */
695 mmput(mm);
696 }
697
698 /* OK to pass negative loff_t, we can catch out-of-range */
699 file->f_mode |= FMODE_UNSIGNED_OFFSET;
700 file->private_data = mm;
701
702 return 0;
703}
704
705static int mem_open(struct inode *inode, struct file *file)
706{
707 return __mem_open(inode, file, PTRACE_MODE_ATTACH);
708}
709
710static ssize_t mem_rw(struct file *file, char __user *buf,
711 size_t count, loff_t *ppos, int write)
712{
713 struct mm_struct *mm = file->private_data;
714 unsigned long addr = *ppos;
715 ssize_t copied;
716 char *page;
717
718 if (!mm)
719 return 0;
720
721 page = (char *)__get_free_page(GFP_TEMPORARY);
722 if (!page)
723 return -ENOMEM;
724
725 copied = 0;
726 if (!atomic_inc_not_zero(&mm->mm_users))
727 goto free;
728
729 while (count > 0) {
730 int this_len = min_t(int, count, PAGE_SIZE);
731
732 if (write && copy_from_user(page, buf, this_len)) {
733 copied = -EFAULT;
734 break;
735 }
736
737 this_len = access_remote_vm(mm, addr, page, this_len, write);
738 if (!this_len) {
739 if (!copied)
740 copied = -EIO;
741 break;
742 }
743
744 if (!write && copy_to_user(buf, page, this_len)) {
745 copied = -EFAULT;
746 break;
747 }
748
749 buf += this_len;
750 addr += this_len;
751 copied += this_len;
752 count -= this_len;
753 }
754 *ppos = addr;
755
756 mmput(mm);
757free:
758 free_page((unsigned long) page);
759 return copied;
760}
761
762static ssize_t mem_read(struct file *file, char __user *buf,
763 size_t count, loff_t *ppos)
764{
765 return mem_rw(file, buf, count, ppos, 0);
766}
767
768static ssize_t mem_write(struct file *file, const char __user *buf,
769 size_t count, loff_t *ppos)
770{
771 return mem_rw(file, (char __user*)buf, count, ppos, 1);
772}
773
774loff_t mem_lseek(struct file *file, loff_t offset, int orig)
775{
776 switch (orig) {
777 case 0:
778 file->f_pos = offset;
779 break;
780 case 1:
781 file->f_pos += offset;
782 break;
783 default:
784 return -EINVAL;
785 }
786 force_successful_syscall_return();
787 return file->f_pos;
788}
789
790static int mem_release(struct inode *inode, struct file *file)
791{
792 struct mm_struct *mm = file->private_data;
793 if (mm)
794 mmdrop(mm);
795 return 0;
796}
797
798static const struct file_operations proc_mem_operations = {
799 .llseek = mem_lseek,
800 .read = mem_read,
801 .write = mem_write,
802 .open = mem_open,
803 .release = mem_release,
804};
805
806static int environ_open(struct inode *inode, struct file *file)
807{
808 return __mem_open(inode, file, PTRACE_MODE_READ);
809}
810
811static ssize_t environ_read(struct file *file, char __user *buf,
812 size_t count, loff_t *ppos)
813{
814 char *page;
815 unsigned long src = *ppos;
816 int ret = 0;
817 struct mm_struct *mm = file->private_data;
818
819 if (!mm)
820 return 0;
821
822 page = (char *)__get_free_page(GFP_TEMPORARY);
823 if (!page)
824 return -ENOMEM;
825
826 ret = 0;
827 if (!atomic_inc_not_zero(&mm->mm_users))
828 goto free;
829 while (count > 0) {
830 int this_len, retval, max_len;
831
832 this_len = mm->env_end - (mm->env_start + src);
833
834 if (this_len <= 0)
835 break;
836
837 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
838 this_len = (this_len > max_len) ? max_len : this_len;
839
840 retval = access_remote_vm(mm, (mm->env_start + src),
841 page, this_len, 0);
842
843 if (retval <= 0) {
844 ret = retval;
845 break;
846 }
847
848 if (copy_to_user(buf, page, retval)) {
849 ret = -EFAULT;
850 break;
851 }
852
853 ret += retval;
854 src += retval;
855 buf += retval;
856 count -= retval;
857 }
858 *ppos = src;
859 mmput(mm);
860
861free:
862 free_page((unsigned long) page);
863 return ret;
864}
865
866static const struct file_operations proc_environ_operations = {
867 .open = environ_open,
868 .read = environ_read,
869 .llseek = generic_file_llseek,
870 .release = mem_release,
871};
872
873static ssize_t oom_adjust_read(struct file *file, char __user *buf,
874 size_t count, loff_t *ppos)
875{
876 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
877 char buffer[PROC_NUMBUF];
878 size_t len;
879 int oom_adjust = OOM_DISABLE;
880 unsigned long flags;
881
882 if (!task)
883 return -ESRCH;
884
885 if (lock_task_sighand(task, &flags)) {
886 oom_adjust = task->signal->oom_adj;
887 unlock_task_sighand(task, &flags);
888 }
889
890 put_task_struct(task);
891
892 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
893
894 return simple_read_from_buffer(buf, count, ppos, buffer, len);
895}
896
897static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
898 size_t count, loff_t *ppos)
899{
900 struct task_struct *task;
901 char buffer[PROC_NUMBUF];
902 int oom_adjust;
903 unsigned long flags;
904 int err;
905
906 memset(buffer, 0, sizeof(buffer));
907 if (count > sizeof(buffer) - 1)
908 count = sizeof(buffer) - 1;
909 if (copy_from_user(buffer, buf, count)) {
910 err = -EFAULT;
911 goto out;
912 }
913
914 err = kstrtoint(strstrip(buffer), 0, &oom_adjust);
915 if (err)
916 goto out;
917 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
918 oom_adjust != OOM_DISABLE) {
919 err = -EINVAL;
920 goto out;
921 }
922
923 task = get_proc_task(file->f_path.dentry->d_inode);
924 if (!task) {
925 err = -ESRCH;
926 goto out;
927 }
928
929 task_lock(task);
930 if (!task->mm) {
931 err = -EINVAL;
932 goto err_task_lock;
933 }
934
935 if (!lock_task_sighand(task, &flags)) {
936 err = -ESRCH;
937 goto err_task_lock;
938 }
939
940 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
941 err = -EACCES;
942 goto err_sighand;
943 }
944
945 /*
946 * Warn that /proc/pid/oom_adj is deprecated, see
947 * Documentation/feature-removal-schedule.txt.
948 */
949 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
950 current->comm, task_pid_nr(current), task_pid_nr(task),
951 task_pid_nr(task));
952 task->signal->oom_adj = oom_adjust;
953 /*
954 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
955 * value is always attainable.
956 */
957 if (task->signal->oom_adj == OOM_ADJUST_MAX)
958 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
959 else
960 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
961 -OOM_DISABLE;
962 trace_oom_score_adj_update(task);
963err_sighand:
964 unlock_task_sighand(task, &flags);
965err_task_lock:
966 task_unlock(task);
967 put_task_struct(task);
968out:
969 return err < 0 ? err : count;
970}
971
972static const struct file_operations proc_oom_adjust_operations = {
973 .read = oom_adjust_read,
974 .write = oom_adjust_write,
975 .llseek = generic_file_llseek,
976};
977
978static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
979 size_t count, loff_t *ppos)
980{
981 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
982 char buffer[PROC_NUMBUF];
983 int oom_score_adj = OOM_SCORE_ADJ_MIN;
984 unsigned long flags;
985 size_t len;
986
987 if (!task)
988 return -ESRCH;
989 if (lock_task_sighand(task, &flags)) {
990 oom_score_adj = task->signal->oom_score_adj;
991 unlock_task_sighand(task, &flags);
992 }
993 put_task_struct(task);
994 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
995 return simple_read_from_buffer(buf, count, ppos, buffer, len);
996}
997
998static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
999 size_t count, loff_t *ppos)
1000{
1001 struct task_struct *task;
1002 char buffer[PROC_NUMBUF];
1003 unsigned long flags;
1004 int oom_score_adj;
1005 int err;
1006
1007 memset(buffer, 0, sizeof(buffer));
1008 if (count > sizeof(buffer) - 1)
1009 count = sizeof(buffer) - 1;
1010 if (copy_from_user(buffer, buf, count)) {
1011 err = -EFAULT;
1012 goto out;
1013 }
1014
1015 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1016 if (err)
1017 goto out;
1018 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1019 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1020 err = -EINVAL;
1021 goto out;
1022 }
1023
1024 task = get_proc_task(file->f_path.dentry->d_inode);
1025 if (!task) {
1026 err = -ESRCH;
1027 goto out;
1028 }
1029
1030 task_lock(task);
1031 if (!task->mm) {
1032 err = -EINVAL;
1033 goto err_task_lock;
1034 }
1035
1036 if (!lock_task_sighand(task, &flags)) {
1037 err = -ESRCH;
1038 goto err_task_lock;
1039 }
1040
1041 if (oom_score_adj < task->signal->oom_score_adj_min &&
1042 !capable(CAP_SYS_RESOURCE)) {
1043 err = -EACCES;
1044 goto err_sighand;
1045 }
1046
1047 task->signal->oom_score_adj = oom_score_adj;
1048 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1049 task->signal->oom_score_adj_min = oom_score_adj;
1050 trace_oom_score_adj_update(task);
1051 /*
1052 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1053 * always attainable.
1054 */
1055 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1056 task->signal->oom_adj = OOM_DISABLE;
1057 else
1058 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1059 OOM_SCORE_ADJ_MAX;
1060err_sighand:
1061 unlock_task_sighand(task, &flags);
1062err_task_lock:
1063 task_unlock(task);
1064 put_task_struct(task);
1065out:
1066 return err < 0 ? err : count;
1067}
1068
1069static const struct file_operations proc_oom_score_adj_operations = {
1070 .read = oom_score_adj_read,
1071 .write = oom_score_adj_write,
1072 .llseek = default_llseek,
1073};
1074
1075#ifdef CONFIG_AUDITSYSCALL
1076#define TMPBUFLEN 21
1077static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1078 size_t count, loff_t *ppos)
1079{
1080 struct inode * inode = file->f_path.dentry->d_inode;
1081 struct task_struct *task = get_proc_task(inode);
1082 ssize_t length;
1083 char tmpbuf[TMPBUFLEN];
1084
1085 if (!task)
1086 return -ESRCH;
1087 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1088 audit_get_loginuid(task));
1089 put_task_struct(task);
1090 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1091}
1092
1093static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1094 size_t count, loff_t *ppos)
1095{
1096 struct inode * inode = file->f_path.dentry->d_inode;
1097 char *page, *tmp;
1098 ssize_t length;
1099 uid_t loginuid;
1100
1101 rcu_read_lock();
1102 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1103 rcu_read_unlock();
1104 return -EPERM;
1105 }
1106 rcu_read_unlock();
1107
1108 if (count >= PAGE_SIZE)
1109 count = PAGE_SIZE - 1;
1110
1111 if (*ppos != 0) {
1112 /* No partial writes. */
1113 return -EINVAL;
1114 }
1115 page = (char*)__get_free_page(GFP_TEMPORARY);
1116 if (!page)
1117 return -ENOMEM;
1118 length = -EFAULT;
1119 if (copy_from_user(page, buf, count))
1120 goto out_free_page;
1121
1122 page[count] = '\0';
1123 loginuid = simple_strtoul(page, &tmp, 10);
1124 if (tmp == page) {
1125 length = -EINVAL;
1126 goto out_free_page;
1127
1128 }
1129 length = audit_set_loginuid(loginuid);
1130 if (likely(length == 0))
1131 length = count;
1132
1133out_free_page:
1134 free_page((unsigned long) page);
1135 return length;
1136}
1137
1138static const struct file_operations proc_loginuid_operations = {
1139 .read = proc_loginuid_read,
1140 .write = proc_loginuid_write,
1141 .llseek = generic_file_llseek,
1142};
1143
1144static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1145 size_t count, loff_t *ppos)
1146{
1147 struct inode * inode = file->f_path.dentry->d_inode;
1148 struct task_struct *task = get_proc_task(inode);
1149 ssize_t length;
1150 char tmpbuf[TMPBUFLEN];
1151
1152 if (!task)
1153 return -ESRCH;
1154 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1155 audit_get_sessionid(task));
1156 put_task_struct(task);
1157 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1158}
1159
1160static const struct file_operations proc_sessionid_operations = {
1161 .read = proc_sessionid_read,
1162 .llseek = generic_file_llseek,
1163};
1164#endif
1165
1166#ifdef CONFIG_FAULT_INJECTION
1167static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1168 size_t count, loff_t *ppos)
1169{
1170 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1171 char buffer[PROC_NUMBUF];
1172 size_t len;
1173 int make_it_fail;
1174
1175 if (!task)
1176 return -ESRCH;
1177 make_it_fail = task->make_it_fail;
1178 put_task_struct(task);
1179
1180 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1181
1182 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1183}
1184
1185static ssize_t proc_fault_inject_write(struct file * file,
1186 const char __user * buf, size_t count, loff_t *ppos)
1187{
1188 struct task_struct *task;
1189 char buffer[PROC_NUMBUF], *end;
1190 int make_it_fail;
1191
1192 if (!capable(CAP_SYS_RESOURCE))
1193 return -EPERM;
1194 memset(buffer, 0, sizeof(buffer));
1195 if (count > sizeof(buffer) - 1)
1196 count = sizeof(buffer) - 1;
1197 if (copy_from_user(buffer, buf, count))
1198 return -EFAULT;
1199 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1200 if (*end)
1201 return -EINVAL;
1202 task = get_proc_task(file->f_dentry->d_inode);
1203 if (!task)
1204 return -ESRCH;
1205 task->make_it_fail = make_it_fail;
1206 put_task_struct(task);
1207
1208 return count;
1209}
1210
1211static const struct file_operations proc_fault_inject_operations = {
1212 .read = proc_fault_inject_read,
1213 .write = proc_fault_inject_write,
1214 .llseek = generic_file_llseek,
1215};
1216#endif
1217
1218
1219#ifdef CONFIG_SCHED_DEBUG
1220/*
1221 * Print out various scheduling related per-task fields:
1222 */
1223static int sched_show(struct seq_file *m, void *v)
1224{
1225 struct inode *inode = m->private;
1226 struct task_struct *p;
1227
1228 p = get_proc_task(inode);
1229 if (!p)
1230 return -ESRCH;
1231 proc_sched_show_task(p, m);
1232
1233 put_task_struct(p);
1234
1235 return 0;
1236}
1237
1238static ssize_t
1239sched_write(struct file *file, const char __user *buf,
1240 size_t count, loff_t *offset)
1241{
1242 struct inode *inode = file->f_path.dentry->d_inode;
1243 struct task_struct *p;
1244
1245 p = get_proc_task(inode);
1246 if (!p)
1247 return -ESRCH;
1248 proc_sched_set_task(p);
1249
1250 put_task_struct(p);
1251
1252 return count;
1253}
1254
1255static int sched_open(struct inode *inode, struct file *filp)
1256{
1257 return single_open(filp, sched_show, inode);
1258}
1259
1260static const struct file_operations proc_pid_sched_operations = {
1261 .open = sched_open,
1262 .read = seq_read,
1263 .write = sched_write,
1264 .llseek = seq_lseek,
1265 .release = single_release,
1266};
1267
1268#endif
1269
1270#ifdef CONFIG_SCHED_AUTOGROUP
1271/*
1272 * Print out autogroup related information:
1273 */
1274static int sched_autogroup_show(struct seq_file *m, void *v)
1275{
1276 struct inode *inode = m->private;
1277 struct task_struct *p;
1278
1279 p = get_proc_task(inode);
1280 if (!p)
1281 return -ESRCH;
1282 proc_sched_autogroup_show_task(p, m);
1283
1284 put_task_struct(p);
1285
1286 return 0;
1287}
1288
1289static ssize_t
1290sched_autogroup_write(struct file *file, const char __user *buf,
1291 size_t count, loff_t *offset)
1292{
1293 struct inode *inode = file->f_path.dentry->d_inode;
1294 struct task_struct *p;
1295 char buffer[PROC_NUMBUF];
1296 int nice;
1297 int err;
1298
1299 memset(buffer, 0, sizeof(buffer));
1300 if (count > sizeof(buffer) - 1)
1301 count = sizeof(buffer) - 1;
1302 if (copy_from_user(buffer, buf, count))
1303 return -EFAULT;
1304
1305 err = kstrtoint(strstrip(buffer), 0, &nice);
1306 if (err < 0)
1307 return err;
1308
1309 p = get_proc_task(inode);
1310 if (!p)
1311 return -ESRCH;
1312
1313 err = proc_sched_autogroup_set_nice(p, nice);
1314 if (err)
1315 count = err;
1316
1317 put_task_struct(p);
1318
1319 return count;
1320}
1321
1322static int sched_autogroup_open(struct inode *inode, struct file *filp)
1323{
1324 int ret;
1325
1326 ret = single_open(filp, sched_autogroup_show, NULL);
1327 if (!ret) {
1328 struct seq_file *m = filp->private_data;
1329
1330 m->private = inode;
1331 }
1332 return ret;
1333}
1334
1335static const struct file_operations proc_pid_sched_autogroup_operations = {
1336 .open = sched_autogroup_open,
1337 .read = seq_read,
1338 .write = sched_autogroup_write,
1339 .llseek = seq_lseek,
1340 .release = single_release,
1341};
1342
1343#endif /* CONFIG_SCHED_AUTOGROUP */
1344
1345static ssize_t comm_write(struct file *file, const char __user *buf,
1346 size_t count, loff_t *offset)
1347{
1348 struct inode *inode = file->f_path.dentry->d_inode;
1349 struct task_struct *p;
1350 char buffer[TASK_COMM_LEN];
1351
1352 memset(buffer, 0, sizeof(buffer));
1353 if (count > sizeof(buffer) - 1)
1354 count = sizeof(buffer) - 1;
1355 if (copy_from_user(buffer, buf, count))
1356 return -EFAULT;
1357
1358 p = get_proc_task(inode);
1359 if (!p)
1360 return -ESRCH;
1361
1362 if (same_thread_group(current, p))
1363 set_task_comm(p, buffer);
1364 else
1365 count = -EINVAL;
1366
1367 put_task_struct(p);
1368
1369 return count;
1370}
1371
1372static int comm_show(struct seq_file *m, void *v)
1373{
1374 struct inode *inode = m->private;
1375 struct task_struct *p;
1376
1377 p = get_proc_task(inode);
1378 if (!p)
1379 return -ESRCH;
1380
1381 task_lock(p);
1382 seq_printf(m, "%s\n", p->comm);
1383 task_unlock(p);
1384
1385 put_task_struct(p);
1386
1387 return 0;
1388}
1389
1390static int comm_open(struct inode *inode, struct file *filp)
1391{
1392 return single_open(filp, comm_show, inode);
1393}
1394
1395static const struct file_operations proc_pid_set_comm_operations = {
1396 .open = comm_open,
1397 .read = seq_read,
1398 .write = comm_write,
1399 .llseek = seq_lseek,
1400 .release = single_release,
1401};
1402
1403static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1404{
1405 struct task_struct *task;
1406 struct mm_struct *mm;
1407 struct file *exe_file;
1408
1409 task = get_proc_task(dentry->d_inode);
1410 if (!task)
1411 return -ENOENT;
1412 mm = get_task_mm(task);
1413 put_task_struct(task);
1414 if (!mm)
1415 return -ENOENT;
1416 exe_file = get_mm_exe_file(mm);
1417 mmput(mm);
1418 if (exe_file) {
1419 *exe_path = exe_file->f_path;
1420 path_get(&exe_file->f_path);
1421 fput(exe_file);
1422 return 0;
1423 } else
1424 return -ENOENT;
1425}
1426
1427static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1428{
1429 struct inode *inode = dentry->d_inode;
1430 int error = -EACCES;
1431
1432 /* We don't need a base pointer in the /proc filesystem */
1433 path_put(&nd->path);
1434
1435 /* Are we allowed to snoop on the tasks file descriptors? */
1436 if (!proc_fd_access_allowed(inode))
1437 goto out;
1438
1439 error = PROC_I(inode)->op.proc_get_link(dentry, &nd->path);
1440out:
1441 return ERR_PTR(error);
1442}
1443
1444static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1445{
1446 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
1447 char *pathname;
1448 int len;
1449
1450 if (!tmp)
1451 return -ENOMEM;
1452
1453 pathname = d_path(path, tmp, PAGE_SIZE);
1454 len = PTR_ERR(pathname);
1455 if (IS_ERR(pathname))
1456 goto out;
1457 len = tmp + PAGE_SIZE - 1 - pathname;
1458
1459 if (len > buflen)
1460 len = buflen;
1461 if (copy_to_user(buffer, pathname, len))
1462 len = -EFAULT;
1463 out:
1464 free_page((unsigned long)tmp);
1465 return len;
1466}
1467
1468static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1469{
1470 int error = -EACCES;
1471 struct inode *inode = dentry->d_inode;
1472 struct path path;
1473
1474 /* Are we allowed to snoop on the tasks file descriptors? */
1475 if (!proc_fd_access_allowed(inode))
1476 goto out;
1477
1478 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1479 if (error)
1480 goto out;
1481
1482 error = do_proc_readlink(&path, buffer, buflen);
1483 path_put(&path);
1484out:
1485 return error;
1486}
1487
1488static const struct inode_operations proc_pid_link_inode_operations = {
1489 .readlink = proc_pid_readlink,
1490 .follow_link = proc_pid_follow_link,
1491 .setattr = proc_setattr,
1492};
1493
1494
1495/* building an inode */
1496
1497static int task_dumpable(struct task_struct *task)
1498{
1499 int dumpable = 0;
1500 struct mm_struct *mm;
1501
1502 task_lock(task);
1503 mm = task->mm;
1504 if (mm)
1505 dumpable = get_dumpable(mm);
1506 task_unlock(task);
1507 if(dumpable == 1)
1508 return 1;
1509 return 0;
1510}
1511
1512struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
1513{
1514 struct inode * inode;
1515 struct proc_inode *ei;
1516 const struct cred *cred;
1517
1518 /* We need a new inode */
1519
1520 inode = new_inode(sb);
1521 if (!inode)
1522 goto out;
1523
1524 /* Common stuff */
1525 ei = PROC_I(inode);
1526 inode->i_ino = get_next_ino();
1527 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1528 inode->i_op = &proc_def_inode_operations;
1529
1530 /*
1531 * grab the reference to task.
1532 */
1533 ei->pid = get_task_pid(task, PIDTYPE_PID);
1534 if (!ei->pid)
1535 goto out_unlock;
1536
1537 if (task_dumpable(task)) {
1538 rcu_read_lock();
1539 cred = __task_cred(task);
1540 inode->i_uid = cred->euid;
1541 inode->i_gid = cred->egid;
1542 rcu_read_unlock();
1543 }
1544 security_task_to_inode(task, inode);
1545
1546out:
1547 return inode;
1548
1549out_unlock:
1550 iput(inode);
1551 return NULL;
1552}
1553
1554int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1555{
1556 struct inode *inode = dentry->d_inode;
1557 struct task_struct *task;
1558 const struct cred *cred;
1559 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
1560
1561 generic_fillattr(inode, stat);
1562
1563 rcu_read_lock();
1564 stat->uid = GLOBAL_ROOT_UID;
1565 stat->gid = GLOBAL_ROOT_GID;
1566 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1567 if (task) {
1568 if (!has_pid_permissions(pid, task, 2)) {
1569 rcu_read_unlock();
1570 /*
1571 * This doesn't prevent learning whether PID exists,
1572 * it only makes getattr() consistent with readdir().
1573 */
1574 return -ENOENT;
1575 }
1576 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1577 task_dumpable(task)) {
1578 cred = __task_cred(task);
1579 stat->uid = cred->euid;
1580 stat->gid = cred->egid;
1581 }
1582 }
1583 rcu_read_unlock();
1584 return 0;
1585}
1586
1587/* dentry stuff */
1588
1589/*
1590 * Exceptional case: normally we are not allowed to unhash a busy
1591 * directory. In this case, however, we can do it - no aliasing problems
1592 * due to the way we treat inodes.
1593 *
1594 * Rewrite the inode's ownerships here because the owning task may have
1595 * performed a setuid(), etc.
1596 *
1597 * Before the /proc/pid/status file was created the only way to read
1598 * the effective uid of a /process was to stat /proc/pid. Reading
1599 * /proc/pid/status is slow enough that procps and other packages
1600 * kept stating /proc/pid. To keep the rules in /proc simple I have
1601 * made this apply to all per process world readable and executable
1602 * directories.
1603 */
1604int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1605{
1606 struct inode *inode;
1607 struct task_struct *task;
1608 const struct cred *cred;
1609
1610 if (nd && nd->flags & LOOKUP_RCU)
1611 return -ECHILD;
1612
1613 inode = dentry->d_inode;
1614 task = get_proc_task(inode);
1615
1616 if (task) {
1617 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1618 task_dumpable(task)) {
1619 rcu_read_lock();
1620 cred = __task_cred(task);
1621 inode->i_uid = cred->euid;
1622 inode->i_gid = cred->egid;
1623 rcu_read_unlock();
1624 } else {
1625 inode->i_uid = GLOBAL_ROOT_UID;
1626 inode->i_gid = GLOBAL_ROOT_GID;
1627 }
1628 inode->i_mode &= ~(S_ISUID | S_ISGID);
1629 security_task_to_inode(task, inode);
1630 put_task_struct(task);
1631 return 1;
1632 }
1633 d_drop(dentry);
1634 return 0;
1635}
1636
1637static int pid_delete_dentry(const struct dentry * dentry)
1638{
1639 /* Is the task we represent dead?
1640 * If so, then don't put the dentry on the lru list,
1641 * kill it immediately.
1642 */
1643 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1644}
1645
1646const struct dentry_operations pid_dentry_operations =
1647{
1648 .d_revalidate = pid_revalidate,
1649 .d_delete = pid_delete_dentry,
1650};
1651
1652/* Lookups */
1653
1654/*
1655 * Fill a directory entry.
1656 *
1657 * If possible create the dcache entry and derive our inode number and
1658 * file type from dcache entry.
1659 *
1660 * Since all of the proc inode numbers are dynamically generated, the inode
1661 * numbers do not exist until the inode is cache. This means creating the
1662 * the dcache entry in readdir is necessary to keep the inode numbers
1663 * reported by readdir in sync with the inode numbers reported
1664 * by stat.
1665 */
1666int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1667 const char *name, int len,
1668 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1669{
1670 struct dentry *child, *dir = filp->f_path.dentry;
1671 struct inode *inode;
1672 struct qstr qname;
1673 ino_t ino = 0;
1674 unsigned type = DT_UNKNOWN;
1675
1676 qname.name = name;
1677 qname.len = len;
1678 qname.hash = full_name_hash(name, len);
1679
1680 child = d_lookup(dir, &qname);
1681 if (!child) {
1682 struct dentry *new;
1683 new = d_alloc(dir, &qname);
1684 if (new) {
1685 child = instantiate(dir->d_inode, new, task, ptr);
1686 if (child)
1687 dput(new);
1688 else
1689 child = new;
1690 }
1691 }
1692 if (!child || IS_ERR(child) || !child->d_inode)
1693 goto end_instantiate;
1694 inode = child->d_inode;
1695 if (inode) {
1696 ino = inode->i_ino;
1697 type = inode->i_mode >> 12;
1698 }
1699 dput(child);
1700end_instantiate:
1701 if (!ino)
1702 ino = find_inode_number(dir, &qname);
1703 if (!ino)
1704 ino = 1;
1705 return filldir(dirent, name, len, filp->f_pos, ino, type);
1706}
1707
1708static unsigned name_to_int(struct dentry *dentry)
1709{
1710 const char *name = dentry->d_name.name;
1711 int len = dentry->d_name.len;
1712 unsigned n = 0;
1713
1714 if (len > 1 && *name == '0')
1715 goto out;
1716 while (len-- > 0) {
1717 unsigned c = *name++ - '0';
1718 if (c > 9)
1719 goto out;
1720 if (n >= (~0U-9)/10)
1721 goto out;
1722 n *= 10;
1723 n += c;
1724 }
1725 return n;
1726out:
1727 return ~0U;
1728}
1729
1730#define PROC_FDINFO_MAX 64
1731
1732static int proc_fd_info(struct inode *inode, struct path *path, char *info)
1733{
1734 struct task_struct *task = get_proc_task(inode);
1735 struct files_struct *files = NULL;
1736 struct file *file;
1737 int fd = proc_fd(inode);
1738
1739 if (task) {
1740 files = get_files_struct(task);
1741 put_task_struct(task);
1742 }
1743 if (files) {
1744 /*
1745 * We are not taking a ref to the file structure, so we must
1746 * hold ->file_lock.
1747 */
1748 spin_lock(&files->file_lock);
1749 file = fcheck_files(files, fd);
1750 if (file) {
1751 unsigned int f_flags;
1752 struct fdtable *fdt;
1753
1754 fdt = files_fdtable(files);
1755 f_flags = file->f_flags & ~O_CLOEXEC;
1756 if (close_on_exec(fd, fdt))
1757 f_flags |= O_CLOEXEC;
1758
1759 if (path) {
1760 *path = file->f_path;
1761 path_get(&file->f_path);
1762 }
1763 if (info)
1764 snprintf(info, PROC_FDINFO_MAX,
1765 "pos:\t%lli\n"
1766 "flags:\t0%o\n",
1767 (long long) file->f_pos,
1768 f_flags);
1769 spin_unlock(&files->file_lock);
1770 put_files_struct(files);
1771 return 0;
1772 }
1773 spin_unlock(&files->file_lock);
1774 put_files_struct(files);
1775 }
1776 return -ENOENT;
1777}
1778
1779static int proc_fd_link(struct dentry *dentry, struct path *path)
1780{
1781 return proc_fd_info(dentry->d_inode, path, NULL);
1782}
1783
1784static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1785{
1786 struct inode *inode;
1787 struct task_struct *task;
1788 int fd;
1789 struct files_struct *files;
1790 const struct cred *cred;
1791
1792 if (nd && nd->flags & LOOKUP_RCU)
1793 return -ECHILD;
1794
1795 inode = dentry->d_inode;
1796 task = get_proc_task(inode);
1797 fd = proc_fd(inode);
1798
1799 if (task) {
1800 files = get_files_struct(task);
1801 if (files) {
1802 struct file *file;
1803 rcu_read_lock();
1804 file = fcheck_files(files, fd);
1805 if (file) {
1806 unsigned f_mode = file->f_mode;
1807
1808 rcu_read_unlock();
1809 put_files_struct(files);
1810
1811 if (task_dumpable(task)) {
1812 rcu_read_lock();
1813 cred = __task_cred(task);
1814 inode->i_uid = cred->euid;
1815 inode->i_gid = cred->egid;
1816 rcu_read_unlock();
1817 } else {
1818 inode->i_uid = GLOBAL_ROOT_UID;
1819 inode->i_gid = GLOBAL_ROOT_GID;
1820 }
1821
1822 if (S_ISLNK(inode->i_mode)) {
1823 unsigned i_mode = S_IFLNK;
1824 if (f_mode & FMODE_READ)
1825 i_mode |= S_IRUSR | S_IXUSR;
1826 if (f_mode & FMODE_WRITE)
1827 i_mode |= S_IWUSR | S_IXUSR;
1828 inode->i_mode = i_mode;
1829 }
1830
1831 security_task_to_inode(task, inode);
1832 put_task_struct(task);
1833 return 1;
1834 }
1835 rcu_read_unlock();
1836 put_files_struct(files);
1837 }
1838 put_task_struct(task);
1839 }
1840 d_drop(dentry);
1841 return 0;
1842}
1843
1844static const struct dentry_operations tid_fd_dentry_operations =
1845{
1846 .d_revalidate = tid_fd_revalidate,
1847 .d_delete = pid_delete_dentry,
1848};
1849
1850static struct dentry *proc_fd_instantiate(struct inode *dir,
1851 struct dentry *dentry, struct task_struct *task, const void *ptr)
1852{
1853 unsigned fd = (unsigned long)ptr;
1854 struct inode *inode;
1855 struct proc_inode *ei;
1856 struct dentry *error = ERR_PTR(-ENOENT);
1857
1858 inode = proc_pid_make_inode(dir->i_sb, task);
1859 if (!inode)
1860 goto out;
1861 ei = PROC_I(inode);
1862 ei->fd = fd;
1863
1864 inode->i_mode = S_IFLNK;
1865 inode->i_op = &proc_pid_link_inode_operations;
1866 inode->i_size = 64;
1867 ei->op.proc_get_link = proc_fd_link;
1868 d_set_d_op(dentry, &tid_fd_dentry_operations);
1869 d_add(dentry, inode);
1870 /* Close the race of the process dying before we return the dentry */
1871 if (tid_fd_revalidate(dentry, NULL))
1872 error = NULL;
1873
1874 out:
1875 return error;
1876}
1877
1878static struct dentry *proc_lookupfd_common(struct inode *dir,
1879 struct dentry *dentry,
1880 instantiate_t instantiate)
1881{
1882 struct task_struct *task = get_proc_task(dir);
1883 unsigned fd = name_to_int(dentry);
1884 struct dentry *result = ERR_PTR(-ENOENT);
1885
1886 if (!task)
1887 goto out_no_task;
1888 if (fd == ~0U)
1889 goto out;
1890
1891 result = instantiate(dir, dentry, task, (void *)(unsigned long)fd);
1892out:
1893 put_task_struct(task);
1894out_no_task:
1895 return result;
1896}
1897
1898static int proc_readfd_common(struct file * filp, void * dirent,
1899 filldir_t filldir, instantiate_t instantiate)
1900{
1901 struct dentry *dentry = filp->f_path.dentry;
1902 struct inode *inode = dentry->d_inode;
1903 struct task_struct *p = get_proc_task(inode);
1904 unsigned int fd, ino;
1905 int retval;
1906 struct files_struct * files;
1907
1908 retval = -ENOENT;
1909 if (!p)
1910 goto out_no_task;
1911 retval = 0;
1912
1913 fd = filp->f_pos;
1914 switch (fd) {
1915 case 0:
1916 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
1917 goto out;
1918 filp->f_pos++;
1919 case 1:
1920 ino = parent_ino(dentry);
1921 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
1922 goto out;
1923 filp->f_pos++;
1924 default:
1925 files = get_files_struct(p);
1926 if (!files)
1927 goto out;
1928 rcu_read_lock();
1929 for (fd = filp->f_pos-2;
1930 fd < files_fdtable(files)->max_fds;
1931 fd++, filp->f_pos++) {
1932 char name[PROC_NUMBUF];
1933 int len;
1934 int rv;
1935
1936 if (!fcheck_files(files, fd))
1937 continue;
1938 rcu_read_unlock();
1939
1940 len = snprintf(name, sizeof(name), "%d", fd);
1941 rv = proc_fill_cache(filp, dirent, filldir,
1942 name, len, instantiate, p,
1943 (void *)(unsigned long)fd);
1944 if (rv < 0)
1945 goto out_fd_loop;
1946 rcu_read_lock();
1947 }
1948 rcu_read_unlock();
1949out_fd_loop:
1950 put_files_struct(files);
1951 }
1952out:
1953 put_task_struct(p);
1954out_no_task:
1955 return retval;
1956}
1957
1958static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
1959 struct nameidata *nd)
1960{
1961 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
1962}
1963
1964static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
1965{
1966 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
1967}
1968
1969static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
1970 size_t len, loff_t *ppos)
1971{
1972 char tmp[PROC_FDINFO_MAX];
1973 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
1974 if (!err)
1975 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
1976 return err;
1977}
1978
1979static const struct file_operations proc_fdinfo_file_operations = {
1980 .open = nonseekable_open,
1981 .read = proc_fdinfo_read,
1982 .llseek = no_llseek,
1983};
1984
1985static const struct file_operations proc_fd_operations = {
1986 .read = generic_read_dir,
1987 .readdir = proc_readfd,
1988 .llseek = default_llseek,
1989};
1990
1991#ifdef CONFIG_CHECKPOINT_RESTORE
1992
1993/*
1994 * dname_to_vma_addr - maps a dentry name into two unsigned longs
1995 * which represent vma start and end addresses.
1996 */
1997static int dname_to_vma_addr(struct dentry *dentry,
1998 unsigned long *start, unsigned long *end)
1999{
2000 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
2001 return -EINVAL;
2002
2003 return 0;
2004}
2005
2006static int map_files_d_revalidate(struct dentry *dentry, struct nameidata *nd)
2007{
2008 unsigned long vm_start, vm_end;
2009 bool exact_vma_exists = false;
2010 struct mm_struct *mm = NULL;
2011 struct task_struct *task;
2012 const struct cred *cred;
2013 struct inode *inode;
2014 int status = 0;
2015
2016 if (nd && nd->flags & LOOKUP_RCU)
2017 return -ECHILD;
2018
2019 if (!capable(CAP_SYS_ADMIN)) {
2020 status = -EACCES;
2021 goto out_notask;
2022 }
2023
2024 inode = dentry->d_inode;
2025 task = get_proc_task(inode);
2026 if (!task)
2027 goto out_notask;
2028
2029 mm = mm_access(task, PTRACE_MODE_READ);
2030 if (IS_ERR_OR_NULL(mm))
2031 goto out;
2032
2033 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2034 down_read(&mm->mmap_sem);
2035 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
2036 up_read(&mm->mmap_sem);
2037 }
2038
2039 mmput(mm);
2040
2041 if (exact_vma_exists) {
2042 if (task_dumpable(task)) {
2043 rcu_read_lock();
2044 cred = __task_cred(task);
2045 inode->i_uid = cred->euid;
2046 inode->i_gid = cred->egid;
2047 rcu_read_unlock();
2048 } else {
2049 inode->i_uid = GLOBAL_ROOT_UID;
2050 inode->i_gid = GLOBAL_ROOT_GID;
2051 }
2052 security_task_to_inode(task, inode);
2053 status = 1;
2054 }
2055
2056out:
2057 put_task_struct(task);
2058
2059out_notask:
2060 if (status <= 0)
2061 d_drop(dentry);
2062
2063 return status;
2064}
2065
2066static const struct dentry_operations tid_map_files_dentry_operations = {
2067 .d_revalidate = map_files_d_revalidate,
2068 .d_delete = pid_delete_dentry,
2069};
2070
2071static int proc_map_files_get_link(struct dentry *dentry, struct path *path)
2072{
2073 unsigned long vm_start, vm_end;
2074 struct vm_area_struct *vma;
2075 struct task_struct *task;
2076 struct mm_struct *mm;
2077 int rc;
2078
2079 rc = -ENOENT;
2080 task = get_proc_task(dentry->d_inode);
2081 if (!task)
2082 goto out;
2083
2084 mm = get_task_mm(task);
2085 put_task_struct(task);
2086 if (!mm)
2087 goto out;
2088
2089 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2090 if (rc)
2091 goto out_mmput;
2092
2093 down_read(&mm->mmap_sem);
2094 vma = find_exact_vma(mm, vm_start, vm_end);
2095 if (vma && vma->vm_file) {
2096 *path = vma->vm_file->f_path;
2097 path_get(path);
2098 rc = 0;
2099 }
2100 up_read(&mm->mmap_sem);
2101
2102out_mmput:
2103 mmput(mm);
2104out:
2105 return rc;
2106}
2107
2108struct map_files_info {
2109 struct file *file;
2110 unsigned long len;
2111 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
2112};
2113
2114static struct dentry *
2115proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2116 struct task_struct *task, const void *ptr)
2117{
2118 const struct file *file = ptr;
2119 struct proc_inode *ei;
2120 struct inode *inode;
2121
2122 if (!file)
2123 return ERR_PTR(-ENOENT);
2124
2125 inode = proc_pid_make_inode(dir->i_sb, task);
2126 if (!inode)
2127 return ERR_PTR(-ENOENT);
2128
2129 ei = PROC_I(inode);
2130 ei->op.proc_get_link = proc_map_files_get_link;
2131
2132 inode->i_op = &proc_pid_link_inode_operations;
2133 inode->i_size = 64;
2134 inode->i_mode = S_IFLNK;
2135
2136 if (file->f_mode & FMODE_READ)
2137 inode->i_mode |= S_IRUSR;
2138 if (file->f_mode & FMODE_WRITE)
2139 inode->i_mode |= S_IWUSR;
2140
2141 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2142 d_add(dentry, inode);
2143
2144 return NULL;
2145}
2146
2147static struct dentry *proc_map_files_lookup(struct inode *dir,
2148 struct dentry *dentry, struct nameidata *nd)
2149{
2150 unsigned long vm_start, vm_end;
2151 struct vm_area_struct *vma;
2152 struct task_struct *task;
2153 struct dentry *result;
2154 struct mm_struct *mm;
2155
2156 result = ERR_PTR(-EACCES);
2157 if (!capable(CAP_SYS_ADMIN))
2158 goto out;
2159
2160 result = ERR_PTR(-ENOENT);
2161 task = get_proc_task(dir);
2162 if (!task)
2163 goto out;
2164
2165 result = ERR_PTR(-EACCES);
2166 if (!ptrace_may_access(task, PTRACE_MODE_READ))
2167 goto out_put_task;
2168
2169 result = ERR_PTR(-ENOENT);
2170 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2171 goto out_put_task;
2172
2173 mm = get_task_mm(task);
2174 if (!mm)
2175 goto out_put_task;
2176
2177 down_read(&mm->mmap_sem);
2178 vma = find_exact_vma(mm, vm_start, vm_end);
2179 if (!vma)
2180 goto out_no_vma;
2181
2182 result = proc_map_files_instantiate(dir, dentry, task, vma->vm_file);
2183
2184out_no_vma:
2185 up_read(&mm->mmap_sem);
2186 mmput(mm);
2187out_put_task:
2188 put_task_struct(task);
2189out:
2190 return result;
2191}
2192
2193static const struct inode_operations proc_map_files_inode_operations = {
2194 .lookup = proc_map_files_lookup,
2195 .permission = proc_fd_permission,
2196 .setattr = proc_setattr,
2197};
2198
2199static int
2200proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
2201{
2202 struct dentry *dentry = filp->f_path.dentry;
2203 struct inode *inode = dentry->d_inode;
2204 struct vm_area_struct *vma;
2205 struct task_struct *task;
2206 struct mm_struct *mm;
2207 ino_t ino;
2208 int ret;
2209
2210 ret = -EACCES;
2211 if (!capable(CAP_SYS_ADMIN))
2212 goto out;
2213
2214 ret = -ENOENT;
2215 task = get_proc_task(inode);
2216 if (!task)
2217 goto out;
2218
2219 ret = -EACCES;
2220 if (!ptrace_may_access(task, PTRACE_MODE_READ))
2221 goto out_put_task;
2222
2223 ret = 0;
2224 switch (filp->f_pos) {
2225 case 0:
2226 ino = inode->i_ino;
2227 if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0)
2228 goto out_put_task;
2229 filp->f_pos++;
2230 case 1:
2231 ino = parent_ino(dentry);
2232 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2233 goto out_put_task;
2234 filp->f_pos++;
2235 default:
2236 {
2237 unsigned long nr_files, pos, i;
2238 struct flex_array *fa = NULL;
2239 struct map_files_info info;
2240 struct map_files_info *p;
2241
2242 mm = get_task_mm(task);
2243 if (!mm)
2244 goto out_put_task;
2245 down_read(&mm->mmap_sem);
2246
2247 nr_files = 0;
2248
2249 /*
2250 * We need two passes here:
2251 *
2252 * 1) Collect vmas of mapped files with mmap_sem taken
2253 * 2) Release mmap_sem and instantiate entries
2254 *
2255 * otherwise we get lockdep complained, since filldir()
2256 * routine might require mmap_sem taken in might_fault().
2257 */
2258
2259 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2260 if (vma->vm_file && ++pos > filp->f_pos)
2261 nr_files++;
2262 }
2263
2264 if (nr_files) {
2265 fa = flex_array_alloc(sizeof(info), nr_files,
2266 GFP_KERNEL);
2267 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2268 GFP_KERNEL)) {
2269 ret = -ENOMEM;
2270 if (fa)
2271 flex_array_free(fa);
2272 up_read(&mm->mmap_sem);
2273 mmput(mm);
2274 goto out_put_task;
2275 }
2276 for (i = 0, vma = mm->mmap, pos = 2; vma;
2277 vma = vma->vm_next) {
2278 if (!vma->vm_file)
2279 continue;
2280 if (++pos <= filp->f_pos)
2281 continue;
2282
2283 get_file(vma->vm_file);
2284 info.file = vma->vm_file;
2285 info.len = snprintf(info.name,
2286 sizeof(info.name), "%lx-%lx",
2287 vma->vm_start, vma->vm_end);
2288 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2289 BUG();
2290 }
2291 }
2292 up_read(&mm->mmap_sem);
2293
2294 for (i = 0; i < nr_files; i++) {
2295 p = flex_array_get(fa, i);
2296 ret = proc_fill_cache(filp, dirent, filldir,
2297 p->name, p->len,
2298 proc_map_files_instantiate,
2299 task, p->file);
2300 if (ret)
2301 break;
2302 filp->f_pos++;
2303 fput(p->file);
2304 }
2305 for (; i < nr_files; i++) {
2306 /*
2307 * In case of error don't forget
2308 * to put rest of file refs.
2309 */
2310 p = flex_array_get(fa, i);
2311 fput(p->file);
2312 }
2313 if (fa)
2314 flex_array_free(fa);
2315 mmput(mm);
2316 }
2317 }
2318
2319out_put_task:
2320 put_task_struct(task);
2321out:
2322 return ret;
2323}
2324
2325static const struct file_operations proc_map_files_operations = {
2326 .read = generic_read_dir,
2327 .readdir = proc_map_files_readdir,
2328 .llseek = default_llseek,
2329};
2330
2331#endif /* CONFIG_CHECKPOINT_RESTORE */
2332
2333/*
2334 * /proc/pid/fd needs a special permission handler so that a process can still
2335 * access /proc/self/fd after it has executed a setuid().
2336 */
2337static int proc_fd_permission(struct inode *inode, int mask)
2338{
2339 int rv = generic_permission(inode, mask);
2340 if (rv == 0)
2341 return 0;
2342 if (task_pid(current) == proc_pid(inode))
2343 rv = 0;
2344 return rv;
2345}
2346
2347/*
2348 * proc directories can do almost nothing..
2349 */
2350static const struct inode_operations proc_fd_inode_operations = {
2351 .lookup = proc_lookupfd,
2352 .permission = proc_fd_permission,
2353 .setattr = proc_setattr,
2354};
2355
2356static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2357 struct dentry *dentry, struct task_struct *task, const void *ptr)
2358{
2359 unsigned fd = (unsigned long)ptr;
2360 struct inode *inode;
2361 struct proc_inode *ei;
2362 struct dentry *error = ERR_PTR(-ENOENT);
2363
2364 inode = proc_pid_make_inode(dir->i_sb, task);
2365 if (!inode)
2366 goto out;
2367 ei = PROC_I(inode);
2368 ei->fd = fd;
2369 inode->i_mode = S_IFREG | S_IRUSR;
2370 inode->i_fop = &proc_fdinfo_file_operations;
2371 d_set_d_op(dentry, &tid_fd_dentry_operations);
2372 d_add(dentry, inode);
2373 /* Close the race of the process dying before we return the dentry */
2374 if (tid_fd_revalidate(dentry, NULL))
2375 error = NULL;
2376
2377 out:
2378 return error;
2379}
2380
2381static struct dentry *proc_lookupfdinfo(struct inode *dir,
2382 struct dentry *dentry,
2383 struct nameidata *nd)
2384{
2385 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2386}
2387
2388static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2389{
2390 return proc_readfd_common(filp, dirent, filldir,
2391 proc_fdinfo_instantiate);
2392}
2393
2394static const struct file_operations proc_fdinfo_operations = {
2395 .read = generic_read_dir,
2396 .readdir = proc_readfdinfo,
2397 .llseek = default_llseek,
2398};
2399
2400/*
2401 * proc directories can do almost nothing..
2402 */
2403static const struct inode_operations proc_fdinfo_inode_operations = {
2404 .lookup = proc_lookupfdinfo,
2405 .setattr = proc_setattr,
2406};
2407
2408
2409static struct dentry *proc_pident_instantiate(struct inode *dir,
2410 struct dentry *dentry, struct task_struct *task, const void *ptr)
2411{
2412 const struct pid_entry *p = ptr;
2413 struct inode *inode;
2414 struct proc_inode *ei;
2415 struct dentry *error = ERR_PTR(-ENOENT);
2416
2417 inode = proc_pid_make_inode(dir->i_sb, task);
2418 if (!inode)
2419 goto out;
2420
2421 ei = PROC_I(inode);
2422 inode->i_mode = p->mode;
2423 if (S_ISDIR(inode->i_mode))
2424 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2425 if (p->iop)
2426 inode->i_op = p->iop;
2427 if (p->fop)
2428 inode->i_fop = p->fop;
2429 ei->op = p->op;
2430 d_set_d_op(dentry, &pid_dentry_operations);
2431 d_add(dentry, inode);
2432 /* Close the race of the process dying before we return the dentry */
2433 if (pid_revalidate(dentry, NULL))
2434 error = NULL;
2435out:
2436 return error;
2437}
2438
2439static struct dentry *proc_pident_lookup(struct inode *dir,
2440 struct dentry *dentry,
2441 const struct pid_entry *ents,
2442 unsigned int nents)
2443{
2444 struct dentry *error;
2445 struct task_struct *task = get_proc_task(dir);
2446 const struct pid_entry *p, *last;
2447
2448 error = ERR_PTR(-ENOENT);
2449
2450 if (!task)
2451 goto out_no_task;
2452
2453 /*
2454 * Yes, it does not scale. And it should not. Don't add
2455 * new entries into /proc/<tgid>/ without very good reasons.
2456 */
2457 last = &ents[nents - 1];
2458 for (p = ents; p <= last; p++) {
2459 if (p->len != dentry->d_name.len)
2460 continue;
2461 if (!memcmp(dentry->d_name.name, p->name, p->len))
2462 break;
2463 }
2464 if (p > last)
2465 goto out;
2466
2467 error = proc_pident_instantiate(dir, dentry, task, p);
2468out:
2469 put_task_struct(task);
2470out_no_task:
2471 return error;
2472}
2473
2474static int proc_pident_fill_cache(struct file *filp, void *dirent,
2475 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2476{
2477 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2478 proc_pident_instantiate, task, p);
2479}
2480
2481static int proc_pident_readdir(struct file *filp,
2482 void *dirent, filldir_t filldir,
2483 const struct pid_entry *ents, unsigned int nents)
2484{
2485 int i;
2486 struct dentry *dentry = filp->f_path.dentry;
2487 struct inode *inode = dentry->d_inode;
2488 struct task_struct *task = get_proc_task(inode);
2489 const struct pid_entry *p, *last;
2490 ino_t ino;
2491 int ret;
2492
2493 ret = -ENOENT;
2494 if (!task)
2495 goto out_no_task;
2496
2497 ret = 0;
2498 i = filp->f_pos;
2499 switch (i) {
2500 case 0:
2501 ino = inode->i_ino;
2502 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2503 goto out;
2504 i++;
2505 filp->f_pos++;
2506 /* fall through */
2507 case 1:
2508 ino = parent_ino(dentry);
2509 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2510 goto out;
2511 i++;
2512 filp->f_pos++;
2513 /* fall through */
2514 default:
2515 i -= 2;
2516 if (i >= nents) {
2517 ret = 1;
2518 goto out;
2519 }
2520 p = ents + i;
2521 last = &ents[nents - 1];
2522 while (p <= last) {
2523 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
2524 goto out;
2525 filp->f_pos++;
2526 p++;
2527 }
2528 }
2529
2530 ret = 1;
2531out:
2532 put_task_struct(task);
2533out_no_task:
2534 return ret;
2535}
2536
2537#ifdef CONFIG_SECURITY
2538static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2539 size_t count, loff_t *ppos)
2540{
2541 struct inode * inode = file->f_path.dentry->d_inode;
2542 char *p = NULL;
2543 ssize_t length;
2544 struct task_struct *task = get_proc_task(inode);
2545
2546 if (!task)
2547 return -ESRCH;
2548
2549 length = security_getprocattr(task,
2550 (char*)file->f_path.dentry->d_name.name,
2551 &p);
2552 put_task_struct(task);
2553 if (length > 0)
2554 length = simple_read_from_buffer(buf, count, ppos, p, length);
2555 kfree(p);
2556 return length;
2557}
2558
2559static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2560 size_t count, loff_t *ppos)
2561{
2562 struct inode * inode = file->f_path.dentry->d_inode;
2563 char *page;
2564 ssize_t length;
2565 struct task_struct *task = get_proc_task(inode);
2566
2567 length = -ESRCH;
2568 if (!task)
2569 goto out_no_task;
2570 if (count > PAGE_SIZE)
2571 count = PAGE_SIZE;
2572
2573 /* No partial writes. */
2574 length = -EINVAL;
2575 if (*ppos != 0)
2576 goto out;
2577
2578 length = -ENOMEM;
2579 page = (char*)__get_free_page(GFP_TEMPORARY);
2580 if (!page)
2581 goto out;
2582
2583 length = -EFAULT;
2584 if (copy_from_user(page, buf, count))
2585 goto out_free;
2586
2587 /* Guard against adverse ptrace interaction */
2588 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
2589 if (length < 0)
2590 goto out_free;
2591
2592 length = security_setprocattr(task,
2593 (char*)file->f_path.dentry->d_name.name,
2594 (void*)page, count);
2595 mutex_unlock(&task->signal->cred_guard_mutex);
2596out_free:
2597 free_page((unsigned long) page);
2598out:
2599 put_task_struct(task);
2600out_no_task:
2601 return length;
2602}
2603
2604static const struct file_operations proc_pid_attr_operations = {
2605 .read = proc_pid_attr_read,
2606 .write = proc_pid_attr_write,
2607 .llseek = generic_file_llseek,
2608};
2609
2610static const struct pid_entry attr_dir_stuff[] = {
2611 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2612 REG("prev", S_IRUGO, proc_pid_attr_operations),
2613 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2614 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2615 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2616 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2617};
2618
2619static int proc_attr_dir_readdir(struct file * filp,
2620 void * dirent, filldir_t filldir)
2621{
2622 return proc_pident_readdir(filp,dirent,filldir,
2623 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
2624}
2625
2626static const struct file_operations proc_attr_dir_operations = {
2627 .read = generic_read_dir,
2628 .readdir = proc_attr_dir_readdir,
2629 .llseek = default_llseek,
2630};
2631
2632static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2633 struct dentry *dentry, struct nameidata *nd)
2634{
2635 return proc_pident_lookup(dir, dentry,
2636 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2637}
2638
2639static const struct inode_operations proc_attr_dir_inode_operations = {
2640 .lookup = proc_attr_dir_lookup,
2641 .getattr = pid_getattr,
2642 .setattr = proc_setattr,
2643};
2644
2645#endif
2646
2647#ifdef CONFIG_ELF_CORE
2648static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2649 size_t count, loff_t *ppos)
2650{
2651 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2652 struct mm_struct *mm;
2653 char buffer[PROC_NUMBUF];
2654 size_t len;
2655 int ret;
2656
2657 if (!task)
2658 return -ESRCH;
2659
2660 ret = 0;
2661 mm = get_task_mm(task);
2662 if (mm) {
2663 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2664 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2665 MMF_DUMP_FILTER_SHIFT));
2666 mmput(mm);
2667 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2668 }
2669
2670 put_task_struct(task);
2671
2672 return ret;
2673}
2674
2675static ssize_t proc_coredump_filter_write(struct file *file,
2676 const char __user *buf,
2677 size_t count,
2678 loff_t *ppos)
2679{
2680 struct task_struct *task;
2681 struct mm_struct *mm;
2682 char buffer[PROC_NUMBUF], *end;
2683 unsigned int val;
2684 int ret;
2685 int i;
2686 unsigned long mask;
2687
2688 ret = -EFAULT;
2689 memset(buffer, 0, sizeof(buffer));
2690 if (count > sizeof(buffer) - 1)
2691 count = sizeof(buffer) - 1;
2692 if (copy_from_user(buffer, buf, count))
2693 goto out_no_task;
2694
2695 ret = -EINVAL;
2696 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2697 if (*end == '\n')
2698 end++;
2699 if (end - buffer == 0)
2700 goto out_no_task;
2701
2702 ret = -ESRCH;
2703 task = get_proc_task(file->f_dentry->d_inode);
2704 if (!task)
2705 goto out_no_task;
2706
2707 ret = end - buffer;
2708 mm = get_task_mm(task);
2709 if (!mm)
2710 goto out_no_mm;
2711
2712 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2713 if (val & mask)
2714 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2715 else
2716 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2717 }
2718
2719 mmput(mm);
2720 out_no_mm:
2721 put_task_struct(task);
2722 out_no_task:
2723 return ret;
2724}
2725
2726static const struct file_operations proc_coredump_filter_operations = {
2727 .read = proc_coredump_filter_read,
2728 .write = proc_coredump_filter_write,
2729 .llseek = generic_file_llseek,
2730};
2731#endif
2732
2733/*
2734 * /proc/self:
2735 */
2736static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2737 int buflen)
2738{
2739 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2740 pid_t tgid = task_tgid_nr_ns(current, ns);
2741 char tmp[PROC_NUMBUF];
2742 if (!tgid)
2743 return -ENOENT;
2744 sprintf(tmp, "%d", tgid);
2745 return vfs_readlink(dentry,buffer,buflen,tmp);
2746}
2747
2748static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2749{
2750 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2751 pid_t tgid = task_tgid_nr_ns(current, ns);
2752 char *name = ERR_PTR(-ENOENT);
2753 if (tgid) {
2754 name = __getname();
2755 if (!name)
2756 name = ERR_PTR(-ENOMEM);
2757 else
2758 sprintf(name, "%d", tgid);
2759 }
2760 nd_set_link(nd, name);
2761 return NULL;
2762}
2763
2764static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2765 void *cookie)
2766{
2767 char *s = nd_get_link(nd);
2768 if (!IS_ERR(s))
2769 __putname(s);
2770}
2771
2772static const struct inode_operations proc_self_inode_operations = {
2773 .readlink = proc_self_readlink,
2774 .follow_link = proc_self_follow_link,
2775 .put_link = proc_self_put_link,
2776};
2777
2778/*
2779 * proc base
2780 *
2781 * These are the directory entries in the root directory of /proc
2782 * that properly belong to the /proc filesystem, as they describe
2783 * describe something that is process related.
2784 */
2785static const struct pid_entry proc_base_stuff[] = {
2786 NOD("self", S_IFLNK|S_IRWXUGO,
2787 &proc_self_inode_operations, NULL, {}),
2788};
2789
2790static struct dentry *proc_base_instantiate(struct inode *dir,
2791 struct dentry *dentry, struct task_struct *task, const void *ptr)
2792{
2793 const struct pid_entry *p = ptr;
2794 struct inode *inode;
2795 struct proc_inode *ei;
2796 struct dentry *error;
2797
2798 /* Allocate the inode */
2799 error = ERR_PTR(-ENOMEM);
2800 inode = new_inode(dir->i_sb);
2801 if (!inode)
2802 goto out;
2803
2804 /* Initialize the inode */
2805 ei = PROC_I(inode);
2806 inode->i_ino = get_next_ino();
2807 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2808
2809 /*
2810 * grab the reference to the task.
2811 */
2812 ei->pid = get_task_pid(task, PIDTYPE_PID);
2813 if (!ei->pid)
2814 goto out_iput;
2815
2816 inode->i_mode = p->mode;
2817 if (S_ISDIR(inode->i_mode))
2818 set_nlink(inode, 2);
2819 if (S_ISLNK(inode->i_mode))
2820 inode->i_size = 64;
2821 if (p->iop)
2822 inode->i_op = p->iop;
2823 if (p->fop)
2824 inode->i_fop = p->fop;
2825 ei->op = p->op;
2826 d_add(dentry, inode);
2827 error = NULL;
2828out:
2829 return error;
2830out_iput:
2831 iput(inode);
2832 goto out;
2833}
2834
2835static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2836{
2837 struct dentry *error;
2838 struct task_struct *task = get_proc_task(dir);
2839 const struct pid_entry *p, *last;
2840
2841 error = ERR_PTR(-ENOENT);
2842
2843 if (!task)
2844 goto out_no_task;
2845
2846 /* Lookup the directory entry */
2847 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2848 for (p = proc_base_stuff; p <= last; p++) {
2849 if (p->len != dentry->d_name.len)
2850 continue;
2851 if (!memcmp(dentry->d_name.name, p->name, p->len))
2852 break;
2853 }
2854 if (p > last)
2855 goto out;
2856
2857 error = proc_base_instantiate(dir, dentry, task, p);
2858
2859out:
2860 put_task_struct(task);
2861out_no_task:
2862 return error;
2863}
2864
2865static int proc_base_fill_cache(struct file *filp, void *dirent,
2866 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2867{
2868 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2869 proc_base_instantiate, task, p);
2870}
2871
2872#ifdef CONFIG_TASK_IO_ACCOUNTING
2873static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2874{
2875 struct task_io_accounting acct = task->ioac;
2876 unsigned long flags;
2877 int result;
2878
2879 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2880 if (result)
2881 return result;
2882
2883 if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
2884 result = -EACCES;
2885 goto out_unlock;
2886 }
2887
2888 if (whole && lock_task_sighand(task, &flags)) {
2889 struct task_struct *t = task;
2890
2891 task_io_accounting_add(&acct, &task->signal->ioac);
2892 while_each_thread(task, t)
2893 task_io_accounting_add(&acct, &t->ioac);
2894
2895 unlock_task_sighand(task, &flags);
2896 }
2897 result = sprintf(buffer,
2898 "rchar: %llu\n"
2899 "wchar: %llu\n"
2900 "syscr: %llu\n"
2901 "syscw: %llu\n"
2902 "read_bytes: %llu\n"
2903 "write_bytes: %llu\n"
2904 "cancelled_write_bytes: %llu\n",
2905 (unsigned long long)acct.rchar,
2906 (unsigned long long)acct.wchar,
2907 (unsigned long long)acct.syscr,
2908 (unsigned long long)acct.syscw,
2909 (unsigned long long)acct.read_bytes,
2910 (unsigned long long)acct.write_bytes,
2911 (unsigned long long)acct.cancelled_write_bytes);
2912out_unlock:
2913 mutex_unlock(&task->signal->cred_guard_mutex);
2914 return result;
2915}
2916
2917static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2918{
2919 return do_io_accounting(task, buffer, 0);
2920}
2921
2922static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2923{
2924 return do_io_accounting(task, buffer, 1);
2925}
2926#endif /* CONFIG_TASK_IO_ACCOUNTING */
2927
2928#ifdef CONFIG_USER_NS
2929static int proc_id_map_open(struct inode *inode, struct file *file,
2930 struct seq_operations *seq_ops)
2931{
2932 struct user_namespace *ns = NULL;
2933 struct task_struct *task;
2934 struct seq_file *seq;
2935 int ret = -EINVAL;
2936
2937 task = get_proc_task(inode);
2938 if (task) {
2939 rcu_read_lock();
2940 ns = get_user_ns(task_cred_xxx(task, user_ns));
2941 rcu_read_unlock();
2942 put_task_struct(task);
2943 }
2944 if (!ns)
2945 goto err;
2946
2947 ret = seq_open(file, seq_ops);
2948 if (ret)
2949 goto err_put_ns;
2950
2951 seq = file->private_data;
2952 seq->private = ns;
2953
2954 return 0;
2955err_put_ns:
2956 put_user_ns(ns);
2957err:
2958 return ret;
2959}
2960
2961static int proc_id_map_release(struct inode *inode, struct file *file)
2962{
2963 struct seq_file *seq = file->private_data;
2964 struct user_namespace *ns = seq->private;
2965 put_user_ns(ns);
2966 return seq_release(inode, file);
2967}
2968
2969static int proc_uid_map_open(struct inode *inode, struct file *file)
2970{
2971 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2972}
2973
2974static int proc_gid_map_open(struct inode *inode, struct file *file)
2975{
2976 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2977}
2978
2979static const struct file_operations proc_uid_map_operations = {
2980 .open = proc_uid_map_open,
2981 .write = proc_uid_map_write,
2982 .read = seq_read,
2983 .llseek = seq_lseek,
2984 .release = proc_id_map_release,
2985};
2986
2987static const struct file_operations proc_gid_map_operations = {
2988 .open = proc_gid_map_open,
2989 .write = proc_gid_map_write,
2990 .read = seq_read,
2991 .llseek = seq_lseek,
2992 .release = proc_id_map_release,
2993};
2994#endif /* CONFIG_USER_NS */
2995
2996static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2997 struct pid *pid, struct task_struct *task)
2998{
2999 int err = lock_trace(task);
3000 if (!err) {
3001 seq_printf(m, "%08x\n", task->personality);
3002 unlock_trace(task);
3003 }
3004 return err;
3005}
3006
3007/*
3008 * Thread groups
3009 */
3010static const struct file_operations proc_task_operations;
3011static const struct inode_operations proc_task_inode_operations;
3012
3013static const struct pid_entry tgid_base_stuff[] = {
3014 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
3015 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3016#ifdef CONFIG_CHECKPOINT_RESTORE
3017 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
3018#endif
3019 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3020 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3021#ifdef CONFIG_NET
3022 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3023#endif
3024 REG("environ", S_IRUSR, proc_environ_operations),
3025 INF("auxv", S_IRUSR, proc_pid_auxv),
3026 ONE("status", S_IRUGO, proc_pid_status),
3027 ONE("personality", S_IRUGO, proc_pid_personality),
3028 INF("limits", S_IRUGO, proc_pid_limits),
3029#ifdef CONFIG_SCHED_DEBUG
3030 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3031#endif
3032#ifdef CONFIG_SCHED_AUTOGROUP
3033 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
3034#endif
3035 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3036#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3037 INF("syscall", S_IRUGO, proc_pid_syscall),
3038#endif
3039 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3040 ONE("stat", S_IRUGO, proc_tgid_stat),
3041 ONE("statm", S_IRUGO, proc_pid_statm),
3042 REG("maps", S_IRUGO, proc_pid_maps_operations),
3043#ifdef CONFIG_NUMA
3044 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
3045#endif
3046 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3047 LNK("cwd", proc_cwd_link),
3048 LNK("root", proc_root_link),
3049 LNK("exe", proc_exe_link),
3050 REG("mounts", S_IRUGO, proc_mounts_operations),
3051 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3052 REG("mountstats", S_IRUSR, proc_mountstats_operations),
3053#ifdef CONFIG_PROC_PAGE_MONITOR
3054 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3055 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
3056 REG("pagemap", S_IRUGO, proc_pagemap_operations),
3057#endif
3058#ifdef CONFIG_SECURITY
3059 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3060#endif
3061#ifdef CONFIG_KALLSYMS
3062 INF("wchan", S_IRUGO, proc_pid_wchan),
3063#endif
3064#ifdef CONFIG_STACKTRACE
3065 ONE("stack", S_IRUGO, proc_pid_stack),
3066#endif
3067#ifdef CONFIG_SCHEDSTATS
3068 INF("schedstat", S_IRUGO, proc_pid_schedstat),
3069#endif
3070#ifdef CONFIG_LATENCYTOP
3071 REG("latency", S_IRUGO, proc_lstats_operations),
3072#endif
3073#ifdef CONFIG_PROC_PID_CPUSET
3074 REG("cpuset", S_IRUGO, proc_cpuset_operations),
3075#endif
3076#ifdef CONFIG_CGROUPS
3077 REG("cgroup", S_IRUGO, proc_cgroup_operations),
3078#endif
3079 INF("oom_score", S_IRUGO, proc_oom_score),
3080 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
3081 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3082#ifdef CONFIG_AUDITSYSCALL
3083 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3084 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3085#endif
3086#ifdef CONFIG_FAULT_INJECTION
3087 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3088#endif
3089#ifdef CONFIG_ELF_CORE
3090 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3091#endif
3092#ifdef CONFIG_TASK_IO_ACCOUNTING
3093 INF("io", S_IRUSR, proc_tgid_io_accounting),
3094#endif
3095#ifdef CONFIG_HARDWALL
3096 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3097#endif
3098#ifdef CONFIG_USER_NS
3099 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3100 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3101#endif
3102};
3103
3104static int proc_tgid_base_readdir(struct file * filp,
3105 void * dirent, filldir_t filldir)
3106{
3107 return proc_pident_readdir(filp,dirent,filldir,
3108 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
3109}
3110
3111static const struct file_operations proc_tgid_base_operations = {
3112 .read = generic_read_dir,
3113 .readdir = proc_tgid_base_readdir,
3114 .llseek = default_llseek,
3115};
3116
3117static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
3118 return proc_pident_lookup(dir, dentry,
3119 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3120}
3121
3122static const struct inode_operations proc_tgid_base_inode_operations = {
3123 .lookup = proc_tgid_base_lookup,
3124 .getattr = pid_getattr,
3125 .setattr = proc_setattr,
3126 .permission = proc_pid_permission,
3127};
3128
3129static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
3130{
3131 struct dentry *dentry, *leader, *dir;
3132 char buf[PROC_NUMBUF];
3133 struct qstr name;
3134
3135 name.name = buf;
3136 name.len = snprintf(buf, sizeof(buf), "%d", pid);
3137 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
3138 if (dentry) {
3139 shrink_dcache_parent(dentry);
3140 d_drop(dentry);
3141 dput(dentry);
3142 }
3143
3144 name.name = buf;
3145 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
3146 leader = d_hash_and_lookup(mnt->mnt_root, &name);
3147 if (!leader)
3148 goto out;
3149
3150 name.name = "task";
3151 name.len = strlen(name.name);
3152 dir = d_hash_and_lookup(leader, &name);
3153 if (!dir)
3154 goto out_put_leader;
3155
3156 name.name = buf;
3157 name.len = snprintf(buf, sizeof(buf), "%d", pid);
3158 dentry = d_hash_and_lookup(dir, &name);
3159 if (dentry) {
3160 shrink_dcache_parent(dentry);
3161 d_drop(dentry);
3162 dput(dentry);
3163 }
3164
3165 dput(dir);
3166out_put_leader:
3167 dput(leader);
3168out:
3169 return;
3170}
3171
3172/**
3173 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3174 * @task: task that should be flushed.
3175 *
3176 * When flushing dentries from proc, one needs to flush them from global
3177 * proc (proc_mnt) and from all the namespaces' procs this task was seen
3178 * in. This call is supposed to do all of this job.
3179 *
3180 * Looks in the dcache for
3181 * /proc/@pid
3182 * /proc/@tgid/task/@pid
3183 * if either directory is present flushes it and all of it'ts children
3184 * from the dcache.
3185 *
3186 * It is safe and reasonable to cache /proc entries for a task until
3187 * that task exits. After that they just clog up the dcache with
3188 * useless entries, possibly causing useful dcache entries to be
3189 * flushed instead. This routine is proved to flush those useless
3190 * dcache entries at process exit time.
3191 *
3192 * NOTE: This routine is just an optimization so it does not guarantee
3193 * that no dcache entries will exist at process exit time it
3194 * just makes it very unlikely that any will persist.
3195 */
3196
3197void proc_flush_task(struct task_struct *task)
3198{
3199 int i;
3200 struct pid *pid, *tgid;
3201 struct upid *upid;
3202
3203 pid = task_pid(task);
3204 tgid = task_tgid(task);
3205
3206 for (i = 0; i <= pid->level; i++) {
3207 upid = &pid->numbers[i];
3208 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
3209 tgid->numbers[i].nr);
3210 }
3211
3212 upid = &pid->numbers[pid->level];
3213 if (upid->nr == 1)
3214 pid_ns_release_proc(upid->ns);
3215}
3216
3217static struct dentry *proc_pid_instantiate(struct inode *dir,
3218 struct dentry * dentry,
3219 struct task_struct *task, const void *ptr)
3220{
3221 struct dentry *error = ERR_PTR(-ENOENT);
3222 struct inode *inode;
3223
3224 inode = proc_pid_make_inode(dir->i_sb, task);
3225 if (!inode)
3226 goto out;
3227
3228 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3229 inode->i_op = &proc_tgid_base_inode_operations;
3230 inode->i_fop = &proc_tgid_base_operations;
3231 inode->i_flags|=S_IMMUTABLE;
3232
3233 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff,
3234 ARRAY_SIZE(tgid_base_stuff)));
3235
3236 d_set_d_op(dentry, &pid_dentry_operations);
3237
3238 d_add(dentry, inode);
3239 /* Close the race of the process dying before we return the dentry */
3240 if (pid_revalidate(dentry, NULL))
3241 error = NULL;
3242out:
3243 return error;
3244}
3245
3246struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3247{
3248 struct dentry *result;
3249 struct task_struct *task;
3250 unsigned tgid;
3251 struct pid_namespace *ns;
3252
3253 result = proc_base_lookup(dir, dentry);
3254 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
3255 goto out;
3256
3257 tgid = name_to_int(dentry);
3258 if (tgid == ~0U)
3259 goto out;
3260
3261 ns = dentry->d_sb->s_fs_info;
3262 rcu_read_lock();
3263 task = find_task_by_pid_ns(tgid, ns);
3264 if (task)
3265 get_task_struct(task);
3266 rcu_read_unlock();
3267 if (!task)
3268 goto out;
3269
3270 result = proc_pid_instantiate(dir, dentry, task, NULL);
3271 put_task_struct(task);
3272out:
3273 return result;
3274}
3275
3276/*
3277 * Find the first task with tgid >= tgid
3278 *
3279 */
3280struct tgid_iter {
3281 unsigned int tgid;
3282 struct task_struct *task;
3283};
3284static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3285{
3286 struct pid *pid;
3287
3288 if (iter.task)
3289 put_task_struct(iter.task);
3290 rcu_read_lock();
3291retry:
3292 iter.task = NULL;
3293 pid = find_ge_pid(iter.tgid, ns);
3294 if (pid) {
3295 iter.tgid = pid_nr_ns(pid, ns);
3296 iter.task = pid_task(pid, PIDTYPE_PID);
3297 /* What we to know is if the pid we have find is the
3298 * pid of a thread_group_leader. Testing for task
3299 * being a thread_group_leader is the obvious thing
3300 * todo but there is a window when it fails, due to
3301 * the pid transfer logic in de_thread.
3302 *
3303 * So we perform the straight forward test of seeing
3304 * if the pid we have found is the pid of a thread
3305 * group leader, and don't worry if the task we have
3306 * found doesn't happen to be a thread group leader.
3307 * As we don't care in the case of readdir.
3308 */
3309 if (!iter.task || !has_group_leader_pid(iter.task)) {
3310 iter.tgid += 1;
3311 goto retry;
3312 }
3313 get_task_struct(iter.task);
3314 }
3315 rcu_read_unlock();
3316 return iter;
3317}
3318
3319#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
3320
3321static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3322 struct tgid_iter iter)
3323{
3324 char name[PROC_NUMBUF];
3325 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
3326 return proc_fill_cache(filp, dirent, filldir, name, len,
3327 proc_pid_instantiate, iter.task, NULL);
3328}
3329
3330static int fake_filldir(void *buf, const char *name, int namelen,
3331 loff_t offset, u64 ino, unsigned d_type)
3332{
3333 return 0;
3334}
3335
3336/* for the /proc/ directory itself, after non-process stuff has been done */
3337int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3338{
3339 unsigned int nr;
3340 struct task_struct *reaper;
3341 struct tgid_iter iter;
3342 struct pid_namespace *ns;
3343 filldir_t __filldir;
3344
3345 if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
3346 goto out_no_task;
3347 nr = filp->f_pos - FIRST_PROCESS_ENTRY;
3348
3349 reaper = get_proc_task(filp->f_path.dentry->d_inode);
3350 if (!reaper)
3351 goto out_no_task;
3352
3353 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
3354 const struct pid_entry *p = &proc_base_stuff[nr];
3355 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
3356 goto out;
3357 }
3358
3359 ns = filp->f_dentry->d_sb->s_fs_info;
3360 iter.task = NULL;
3361 iter.tgid = filp->f_pos - TGID_OFFSET;
3362 for (iter = next_tgid(ns, iter);
3363 iter.task;
3364 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3365 if (has_pid_permissions(ns, iter.task, 2))
3366 __filldir = filldir;
3367 else
3368 __filldir = fake_filldir;
3369
3370 filp->f_pos = iter.tgid + TGID_OFFSET;
3371 if (proc_pid_fill_cache(filp, dirent, __filldir, iter) < 0) {
3372 put_task_struct(iter.task);
3373 goto out;
3374 }
3375 }
3376 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3377out:
3378 put_task_struct(reaper);
3379out_no_task:
3380 return 0;
3381}
3382
3383/*
3384 * Tasks
3385 */
3386static const struct pid_entry tid_base_stuff[] = {
3387 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3388 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3389 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3390 REG("environ", S_IRUSR, proc_environ_operations),
3391 INF("auxv", S_IRUSR, proc_pid_auxv),
3392 ONE("status", S_IRUGO, proc_pid_status),
3393 ONE("personality", S_IRUGO, proc_pid_personality),
3394 INF("limits", S_IRUGO, proc_pid_limits),
3395#ifdef CONFIG_SCHED_DEBUG
3396 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3397#endif
3398 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3399#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3400 INF("syscall", S_IRUGO, proc_pid_syscall),
3401#endif
3402 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3403 ONE("stat", S_IRUGO, proc_tid_stat),
3404 ONE("statm", S_IRUGO, proc_pid_statm),
3405 REG("maps", S_IRUGO, proc_tid_maps_operations),
3406#ifdef CONFIG_CHECKPOINT_RESTORE
3407 REG("children", S_IRUGO, proc_tid_children_operations),
3408#endif
3409#ifdef CONFIG_NUMA
3410 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
3411#endif
3412 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3413 LNK("cwd", proc_cwd_link),
3414 LNK("root", proc_root_link),
3415 LNK("exe", proc_exe_link),
3416 REG("mounts", S_IRUGO, proc_mounts_operations),
3417 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3418#ifdef CONFIG_PROC_PAGE_MONITOR
3419 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3420 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
3421 REG("pagemap", S_IRUGO, proc_pagemap_operations),
3422#endif
3423#ifdef CONFIG_SECURITY
3424 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3425#endif
3426#ifdef CONFIG_KALLSYMS
3427 INF("wchan", S_IRUGO, proc_pid_wchan),
3428#endif
3429#ifdef CONFIG_STACKTRACE
3430 ONE("stack", S_IRUGO, proc_pid_stack),
3431#endif
3432#ifdef CONFIG_SCHEDSTATS
3433 INF("schedstat", S_IRUGO, proc_pid_schedstat),
3434#endif
3435#ifdef CONFIG_LATENCYTOP
3436 REG("latency", S_IRUGO, proc_lstats_operations),
3437#endif
3438#ifdef CONFIG_PROC_PID_CPUSET
3439 REG("cpuset", S_IRUGO, proc_cpuset_operations),
3440#endif
3441#ifdef CONFIG_CGROUPS
3442 REG("cgroup", S_IRUGO, proc_cgroup_operations),
3443#endif
3444 INF("oom_score", S_IRUGO, proc_oom_score),
3445 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
3446 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3447#ifdef CONFIG_AUDITSYSCALL
3448 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3449 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3450#endif
3451#ifdef CONFIG_FAULT_INJECTION
3452 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3453#endif
3454#ifdef CONFIG_TASK_IO_ACCOUNTING
3455 INF("io", S_IRUSR, proc_tid_io_accounting),
3456#endif
3457#ifdef CONFIG_HARDWALL
3458 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3459#endif
3460#ifdef CONFIG_USER_NS
3461 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3462 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3463#endif
3464};
3465
3466static int proc_tid_base_readdir(struct file * filp,
3467 void * dirent, filldir_t filldir)
3468{
3469 return proc_pident_readdir(filp,dirent,filldir,
3470 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3471}
3472
3473static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
3474 return proc_pident_lookup(dir, dentry,
3475 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3476}
3477
3478static const struct file_operations proc_tid_base_operations = {
3479 .read = generic_read_dir,
3480 .readdir = proc_tid_base_readdir,
3481 .llseek = default_llseek,
3482};
3483
3484static const struct inode_operations proc_tid_base_inode_operations = {
3485 .lookup = proc_tid_base_lookup,
3486 .getattr = pid_getattr,
3487 .setattr = proc_setattr,
3488};
3489
3490static struct dentry *proc_task_instantiate(struct inode *dir,
3491 struct dentry *dentry, struct task_struct *task, const void *ptr)
3492{
3493 struct dentry *error = ERR_PTR(-ENOENT);
3494 struct inode *inode;
3495 inode = proc_pid_make_inode(dir->i_sb, task);
3496
3497 if (!inode)
3498 goto out;
3499 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3500 inode->i_op = &proc_tid_base_inode_operations;
3501 inode->i_fop = &proc_tid_base_operations;
3502 inode->i_flags|=S_IMMUTABLE;
3503
3504 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff,
3505 ARRAY_SIZE(tid_base_stuff)));
3506
3507 d_set_d_op(dentry, &pid_dentry_operations);
3508
3509 d_add(dentry, inode);
3510 /* Close the race of the process dying before we return the dentry */
3511 if (pid_revalidate(dentry, NULL))
3512 error = NULL;
3513out:
3514 return error;
3515}
3516
3517static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3518{
3519 struct dentry *result = ERR_PTR(-ENOENT);
3520 struct task_struct *task;
3521 struct task_struct *leader = get_proc_task(dir);
3522 unsigned tid;
3523 struct pid_namespace *ns;
3524
3525 if (!leader)
3526 goto out_no_task;
3527
3528 tid = name_to_int(dentry);
3529 if (tid == ~0U)
3530 goto out;
3531
3532 ns = dentry->d_sb->s_fs_info;
3533 rcu_read_lock();
3534 task = find_task_by_pid_ns(tid, ns);
3535 if (task)
3536 get_task_struct(task);
3537 rcu_read_unlock();
3538 if (!task)
3539 goto out;
3540 if (!same_thread_group(leader, task))
3541 goto out_drop_task;
3542
3543 result = proc_task_instantiate(dir, dentry, task, NULL);
3544out_drop_task:
3545 put_task_struct(task);
3546out:
3547 put_task_struct(leader);
3548out_no_task:
3549 return result;
3550}
3551
3552/*
3553 * Find the first tid of a thread group to return to user space.
3554 *
3555 * Usually this is just the thread group leader, but if the users
3556 * buffer was too small or there was a seek into the middle of the
3557 * directory we have more work todo.
3558 *
3559 * In the case of a short read we start with find_task_by_pid.
3560 *
3561 * In the case of a seek we start with the leader and walk nr
3562 * threads past it.
3563 */
3564static struct task_struct *first_tid(struct task_struct *leader,
3565 int tid, int nr, struct pid_namespace *ns)
3566{
3567 struct task_struct *pos;
3568
3569 rcu_read_lock();
3570 /* Attempt to start with the pid of a thread */
3571 if (tid && (nr > 0)) {
3572 pos = find_task_by_pid_ns(tid, ns);
3573 if (pos && (pos->group_leader == leader))
3574 goto found;
3575 }
3576
3577 /* If nr exceeds the number of threads there is nothing todo */
3578 pos = NULL;
3579 if (nr && nr >= get_nr_threads(leader))
3580 goto out;
3581
3582 /* If we haven't found our starting place yet start
3583 * with the leader and walk nr threads forward.
3584 */
3585 for (pos = leader; nr > 0; --nr) {
3586 pos = next_thread(pos);
3587 if (pos == leader) {
3588 pos = NULL;
3589 goto out;
3590 }
3591 }
3592found:
3593 get_task_struct(pos);
3594out:
3595 rcu_read_unlock();
3596 return pos;
3597}
3598
3599/*
3600 * Find the next thread in the thread list.
3601 * Return NULL if there is an error or no next thread.
3602 *
3603 * The reference to the input task_struct is released.
3604 */
3605static struct task_struct *next_tid(struct task_struct *start)
3606{
3607 struct task_struct *pos = NULL;
3608 rcu_read_lock();
3609 if (pid_alive(start)) {
3610 pos = next_thread(start);
3611 if (thread_group_leader(pos))
3612 pos = NULL;
3613 else
3614 get_task_struct(pos);
3615 }
3616 rcu_read_unlock();
3617 put_task_struct(start);
3618 return pos;
3619}
3620
3621static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3622 struct task_struct *task, int tid)
3623{
3624 char name[PROC_NUMBUF];
3625 int len = snprintf(name, sizeof(name), "%d", tid);
3626 return proc_fill_cache(filp, dirent, filldir, name, len,
3627 proc_task_instantiate, task, NULL);
3628}
3629
3630/* for the /proc/TGID/task/ directories */
3631static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3632{
3633 struct dentry *dentry = filp->f_path.dentry;
3634 struct inode *inode = dentry->d_inode;
3635 struct task_struct *leader = NULL;
3636 struct task_struct *task;
3637 int retval = -ENOENT;
3638 ino_t ino;
3639 int tid;
3640 struct pid_namespace *ns;
3641
3642 task = get_proc_task(inode);
3643 if (!task)
3644 goto out_no_task;
3645 rcu_read_lock();
3646 if (pid_alive(task)) {
3647 leader = task->group_leader;
3648 get_task_struct(leader);
3649 }
3650 rcu_read_unlock();
3651 put_task_struct(task);
3652 if (!leader)
3653 goto out_no_task;
3654 retval = 0;
3655
3656 switch ((unsigned long)filp->f_pos) {
3657 case 0:
3658 ino = inode->i_ino;
3659 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
3660 goto out;
3661 filp->f_pos++;
3662 /* fall through */
3663 case 1:
3664 ino = parent_ino(dentry);
3665 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
3666 goto out;
3667 filp->f_pos++;
3668 /* fall through */
3669 }
3670
3671 /* f_version caches the tgid value that the last readdir call couldn't
3672 * return. lseek aka telldir automagically resets f_version to 0.
3673 */
3674 ns = filp->f_dentry->d_sb->s_fs_info;
3675 tid = (int)filp->f_version;
3676 filp->f_version = 0;
3677 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
3678 task;
3679 task = next_tid(task), filp->f_pos++) {
3680 tid = task_pid_nr_ns(task, ns);
3681 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
3682 /* returning this tgid failed, save it as the first
3683 * pid for the next readir call */
3684 filp->f_version = (u64)tid;
3685 put_task_struct(task);
3686 break;
3687 }
3688 }
3689out:
3690 put_task_struct(leader);
3691out_no_task:
3692 return retval;
3693}
3694
3695static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3696{
3697 struct inode *inode = dentry->d_inode;
3698 struct task_struct *p = get_proc_task(inode);
3699 generic_fillattr(inode, stat);
3700
3701 if (p) {
3702 stat->nlink += get_nr_threads(p);
3703 put_task_struct(p);
3704 }
3705
3706 return 0;
3707}
3708
3709static const struct inode_operations proc_task_inode_operations = {
3710 .lookup = proc_task_lookup,
3711 .getattr = proc_task_getattr,
3712 .setattr = proc_setattr,
3713 .permission = proc_pid_permission,
3714};
3715
3716static const struct file_operations proc_task_operations = {
3717 .read = generic_read_dir,
3718 .readdir = proc_task_readdir,
3719 .llseek = default_llseek,
3720};