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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/fs_struct.h>
85#include <linux/slab.h>
86#ifdef CONFIG_HARDWALL
87#include <asm/hardwall.h>
88#endif
89#include "internal.h"
90
91/* NOTE:
92 * Implementing inode permission operations in /proc is almost
93 * certainly an error. Permission checks need to happen during
94 * each system call not at open time. The reason is that most of
95 * what we wish to check for permissions in /proc varies at runtime.
96 *
97 * The classic example of a problem is opening file descriptors
98 * in /proc for a task before it execs a suid executable.
99 */
100
101struct pid_entry {
102 char *name;
103 int len;
104 mode_t mode;
105 const struct inode_operations *iop;
106 const struct file_operations *fop;
107 union proc_op op;
108};
109
110#define NOD(NAME, MODE, IOP, FOP, OP) { \
111 .name = (NAME), \
112 .len = sizeof(NAME) - 1, \
113 .mode = MODE, \
114 .iop = IOP, \
115 .fop = FOP, \
116 .op = OP, \
117}
118
119#define DIR(NAME, MODE, iops, fops) \
120 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
121#define LNK(NAME, get_link) \
122 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
123 &proc_pid_link_inode_operations, NULL, \
124 { .proc_get_link = get_link } )
125#define REG(NAME, MODE, fops) \
126 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
127#define INF(NAME, MODE, read) \
128 NOD(NAME, (S_IFREG|(MODE)), \
129 NULL, &proc_info_file_operations, \
130 { .proc_read = read } )
131#define ONE(NAME, MODE, show) \
132 NOD(NAME, (S_IFREG|(MODE)), \
133 NULL, &proc_single_file_operations, \
134 { .proc_show = show } )
135
136/*
137 * Count the number of hardlinks for the pid_entry table, excluding the .
138 * and .. links.
139 */
140static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
141 unsigned int n)
142{
143 unsigned int i;
144 unsigned int count;
145
146 count = 0;
147 for (i = 0; i < n; ++i) {
148 if (S_ISDIR(entries[i].mode))
149 ++count;
150 }
151
152 return count;
153}
154
155static int get_task_root(struct task_struct *task, struct path *root)
156{
157 int result = -ENOENT;
158
159 task_lock(task);
160 if (task->fs) {
161 get_fs_root(task->fs, root);
162 result = 0;
163 }
164 task_unlock(task);
165 return result;
166}
167
168static int proc_cwd_link(struct inode *inode, struct path *path)
169{
170 struct task_struct *task = get_proc_task(inode);
171 int result = -ENOENT;
172
173 if (task) {
174 task_lock(task);
175 if (task->fs) {
176 get_fs_pwd(task->fs, path);
177 result = 0;
178 }
179 task_unlock(task);
180 put_task_struct(task);
181 }
182 return result;
183}
184
185static int proc_root_link(struct inode *inode, struct path *path)
186{
187 struct task_struct *task = get_proc_task(inode);
188 int result = -ENOENT;
189
190 if (task) {
191 result = get_task_root(task, path);
192 put_task_struct(task);
193 }
194 return result;
195}
196
197static struct mm_struct *__check_mem_permission(struct task_struct *task)
198{
199 struct mm_struct *mm;
200
201 mm = get_task_mm(task);
202 if (!mm)
203 return ERR_PTR(-EINVAL);
204
205 /*
206 * A task can always look at itself, in case it chooses
207 * to use system calls instead of load instructions.
208 */
209 if (task == current)
210 return mm;
211
212 /*
213 * If current is actively ptrace'ing, and would also be
214 * permitted to freshly attach with ptrace now, permit it.
215 */
216 if (task_is_stopped_or_traced(task)) {
217 int match;
218 rcu_read_lock();
219 match = (ptrace_parent(task) == current);
220 rcu_read_unlock();
221 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
222 return mm;
223 }
224
225 /*
226 * No one else is allowed.
227 */
228 mmput(mm);
229 return ERR_PTR(-EPERM);
230}
231
232/*
233 * If current may access user memory in @task return a reference to the
234 * corresponding mm, otherwise ERR_PTR.
235 */
236static struct mm_struct *check_mem_permission(struct task_struct *task)
237{
238 struct mm_struct *mm;
239 int err;
240
241 /*
242 * Avoid racing if task exec's as we might get a new mm but validate
243 * against old credentials.
244 */
245 err = mutex_lock_killable(&task->signal->cred_guard_mutex);
246 if (err)
247 return ERR_PTR(err);
248
249 mm = __check_mem_permission(task);
250 mutex_unlock(&task->signal->cred_guard_mutex);
251
252 return mm;
253}
254
255struct mm_struct *mm_for_maps(struct task_struct *task)
256{
257 struct mm_struct *mm;
258 int err;
259
260 err = mutex_lock_killable(&task->signal->cred_guard_mutex);
261 if (err)
262 return ERR_PTR(err);
263
264 mm = get_task_mm(task);
265 if (mm && mm != current->mm &&
266 !ptrace_may_access(task, PTRACE_MODE_READ)) {
267 mmput(mm);
268 mm = ERR_PTR(-EACCES);
269 }
270 mutex_unlock(&task->signal->cred_guard_mutex);
271
272 return mm;
273}
274
275static int proc_pid_cmdline(struct task_struct *task, char * buffer)
276{
277 int res = 0;
278 unsigned int len;
279 struct mm_struct *mm = get_task_mm(task);
280 if (!mm)
281 goto out;
282 if (!mm->arg_end)
283 goto out_mm; /* Shh! No looking before we're done */
284
285 len = mm->arg_end - mm->arg_start;
286
287 if (len > PAGE_SIZE)
288 len = PAGE_SIZE;
289
290 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
291
292 // If the nul at the end of args has been overwritten, then
293 // assume application is using setproctitle(3).
294 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
295 len = strnlen(buffer, res);
296 if (len < res) {
297 res = len;
298 } else {
299 len = mm->env_end - mm->env_start;
300 if (len > PAGE_SIZE - res)
301 len = PAGE_SIZE - res;
302 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
303 res = strnlen(buffer, res);
304 }
305 }
306out_mm:
307 mmput(mm);
308out:
309 return res;
310}
311
312static int proc_pid_auxv(struct task_struct *task, char *buffer)
313{
314 struct mm_struct *mm = mm_for_maps(task);
315 int res = PTR_ERR(mm);
316 if (mm && !IS_ERR(mm)) {
317 unsigned int nwords = 0;
318 do {
319 nwords += 2;
320 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
321 res = nwords * sizeof(mm->saved_auxv[0]);
322 if (res > PAGE_SIZE)
323 res = PAGE_SIZE;
324 memcpy(buffer, mm->saved_auxv, res);
325 mmput(mm);
326 }
327 return res;
328}
329
330
331#ifdef CONFIG_KALLSYMS
332/*
333 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
334 * Returns the resolved symbol. If that fails, simply return the address.
335 */
336static int proc_pid_wchan(struct task_struct *task, char *buffer)
337{
338 unsigned long wchan;
339 char symname[KSYM_NAME_LEN];
340
341 wchan = get_wchan(task);
342
343 if (lookup_symbol_name(wchan, symname) < 0)
344 if (!ptrace_may_access(task, PTRACE_MODE_READ))
345 return 0;
346 else
347 return sprintf(buffer, "%lu", wchan);
348 else
349 return sprintf(buffer, "%s", symname);
350}
351#endif /* CONFIG_KALLSYMS */
352
353static int lock_trace(struct task_struct *task)
354{
355 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
356 if (err)
357 return err;
358 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
359 mutex_unlock(&task->signal->cred_guard_mutex);
360 return -EPERM;
361 }
362 return 0;
363}
364
365static void unlock_trace(struct task_struct *task)
366{
367 mutex_unlock(&task->signal->cred_guard_mutex);
368}
369
370#ifdef CONFIG_STACKTRACE
371
372#define MAX_STACK_TRACE_DEPTH 64
373
374static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
375 struct pid *pid, struct task_struct *task)
376{
377 struct stack_trace trace;
378 unsigned long *entries;
379 int err;
380 int i;
381
382 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
383 if (!entries)
384 return -ENOMEM;
385
386 trace.nr_entries = 0;
387 trace.max_entries = MAX_STACK_TRACE_DEPTH;
388 trace.entries = entries;
389 trace.skip = 0;
390
391 err = lock_trace(task);
392 if (!err) {
393 save_stack_trace_tsk(task, &trace);
394
395 for (i = 0; i < trace.nr_entries; i++) {
396 seq_printf(m, "[<%pK>] %pS\n",
397 (void *)entries[i], (void *)entries[i]);
398 }
399 unlock_trace(task);
400 }
401 kfree(entries);
402
403 return err;
404}
405#endif
406
407#ifdef CONFIG_SCHEDSTATS
408/*
409 * Provides /proc/PID/schedstat
410 */
411static int proc_pid_schedstat(struct task_struct *task, char *buffer)
412{
413 return sprintf(buffer, "%llu %llu %lu\n",
414 (unsigned long long)task->se.sum_exec_runtime,
415 (unsigned long long)task->sched_info.run_delay,
416 task->sched_info.pcount);
417}
418#endif
419
420#ifdef CONFIG_LATENCYTOP
421static int lstats_show_proc(struct seq_file *m, void *v)
422{
423 int i;
424 struct inode *inode = m->private;
425 struct task_struct *task = get_proc_task(inode);
426
427 if (!task)
428 return -ESRCH;
429 seq_puts(m, "Latency Top version : v0.1\n");
430 for (i = 0; i < 32; i++) {
431 struct latency_record *lr = &task->latency_record[i];
432 if (lr->backtrace[0]) {
433 int q;
434 seq_printf(m, "%i %li %li",
435 lr->count, lr->time, lr->max);
436 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
437 unsigned long bt = lr->backtrace[q];
438 if (!bt)
439 break;
440 if (bt == ULONG_MAX)
441 break;
442 seq_printf(m, " %ps", (void *)bt);
443 }
444 seq_putc(m, '\n');
445 }
446
447 }
448 put_task_struct(task);
449 return 0;
450}
451
452static int lstats_open(struct inode *inode, struct file *file)
453{
454 return single_open(file, lstats_show_proc, inode);
455}
456
457static ssize_t lstats_write(struct file *file, const char __user *buf,
458 size_t count, loff_t *offs)
459{
460 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
461
462 if (!task)
463 return -ESRCH;
464 clear_all_latency_tracing(task);
465 put_task_struct(task);
466
467 return count;
468}
469
470static const struct file_operations proc_lstats_operations = {
471 .open = lstats_open,
472 .read = seq_read,
473 .write = lstats_write,
474 .llseek = seq_lseek,
475 .release = single_release,
476};
477
478#endif
479
480static int proc_oom_score(struct task_struct *task, char *buffer)
481{
482 unsigned long points = 0;
483
484 read_lock(&tasklist_lock);
485 if (pid_alive(task))
486 points = oom_badness(task, NULL, NULL,
487 totalram_pages + total_swap_pages);
488 read_unlock(&tasklist_lock);
489 return sprintf(buffer, "%lu\n", points);
490}
491
492struct limit_names {
493 char *name;
494 char *unit;
495};
496
497static const struct limit_names lnames[RLIM_NLIMITS] = {
498 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
499 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
500 [RLIMIT_DATA] = {"Max data size", "bytes"},
501 [RLIMIT_STACK] = {"Max stack size", "bytes"},
502 [RLIMIT_CORE] = {"Max core file size", "bytes"},
503 [RLIMIT_RSS] = {"Max resident set", "bytes"},
504 [RLIMIT_NPROC] = {"Max processes", "processes"},
505 [RLIMIT_NOFILE] = {"Max open files", "files"},
506 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
507 [RLIMIT_AS] = {"Max address space", "bytes"},
508 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
509 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
510 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
511 [RLIMIT_NICE] = {"Max nice priority", NULL},
512 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
513 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
514};
515
516/* Display limits for a process */
517static int proc_pid_limits(struct task_struct *task, char *buffer)
518{
519 unsigned int i;
520 int count = 0;
521 unsigned long flags;
522 char *bufptr = buffer;
523
524 struct rlimit rlim[RLIM_NLIMITS];
525
526 if (!lock_task_sighand(task, &flags))
527 return 0;
528 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
529 unlock_task_sighand(task, &flags);
530
531 /*
532 * print the file header
533 */
534 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
535 "Limit", "Soft Limit", "Hard Limit", "Units");
536
537 for (i = 0; i < RLIM_NLIMITS; i++) {
538 if (rlim[i].rlim_cur == RLIM_INFINITY)
539 count += sprintf(&bufptr[count], "%-25s %-20s ",
540 lnames[i].name, "unlimited");
541 else
542 count += sprintf(&bufptr[count], "%-25s %-20lu ",
543 lnames[i].name, rlim[i].rlim_cur);
544
545 if (rlim[i].rlim_max == RLIM_INFINITY)
546 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
547 else
548 count += sprintf(&bufptr[count], "%-20lu ",
549 rlim[i].rlim_max);
550
551 if (lnames[i].unit)
552 count += sprintf(&bufptr[count], "%-10s\n",
553 lnames[i].unit);
554 else
555 count += sprintf(&bufptr[count], "\n");
556 }
557
558 return count;
559}
560
561#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
562static int proc_pid_syscall(struct task_struct *task, char *buffer)
563{
564 long nr;
565 unsigned long args[6], sp, pc;
566 int res = lock_trace(task);
567 if (res)
568 return res;
569
570 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
571 res = sprintf(buffer, "running\n");
572 else if (nr < 0)
573 res = sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
574 else
575 res = sprintf(buffer,
576 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
577 nr,
578 args[0], args[1], args[2], args[3], args[4], args[5],
579 sp, pc);
580 unlock_trace(task);
581 return res;
582}
583#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
584
585/************************************************************************/
586/* Here the fs part begins */
587/************************************************************************/
588
589/* permission checks */
590static int proc_fd_access_allowed(struct inode *inode)
591{
592 struct task_struct *task;
593 int allowed = 0;
594 /* Allow access to a task's file descriptors if it is us or we
595 * may use ptrace attach to the process and find out that
596 * information.
597 */
598 task = get_proc_task(inode);
599 if (task) {
600 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
601 put_task_struct(task);
602 }
603 return allowed;
604}
605
606int proc_setattr(struct dentry *dentry, struct iattr *attr)
607{
608 int error;
609 struct inode *inode = dentry->d_inode;
610
611 if (attr->ia_valid & ATTR_MODE)
612 return -EPERM;
613
614 error = inode_change_ok(inode, attr);
615 if (error)
616 return error;
617
618 if ((attr->ia_valid & ATTR_SIZE) &&
619 attr->ia_size != i_size_read(inode)) {
620 error = vmtruncate(inode, attr->ia_size);
621 if (error)
622 return error;
623 }
624
625 setattr_copy(inode, attr);
626 mark_inode_dirty(inode);
627 return 0;
628}
629
630static const struct inode_operations proc_def_inode_operations = {
631 .setattr = proc_setattr,
632};
633
634static int mounts_open_common(struct inode *inode, struct file *file,
635 const struct seq_operations *op)
636{
637 struct task_struct *task = get_proc_task(inode);
638 struct nsproxy *nsp;
639 struct mnt_namespace *ns = NULL;
640 struct path root;
641 struct proc_mounts *p;
642 int ret = -EINVAL;
643
644 if (task) {
645 rcu_read_lock();
646 nsp = task_nsproxy(task);
647 if (nsp) {
648 ns = nsp->mnt_ns;
649 if (ns)
650 get_mnt_ns(ns);
651 }
652 rcu_read_unlock();
653 if (ns && get_task_root(task, &root) == 0)
654 ret = 0;
655 put_task_struct(task);
656 }
657
658 if (!ns)
659 goto err;
660 if (ret)
661 goto err_put_ns;
662
663 ret = -ENOMEM;
664 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
665 if (!p)
666 goto err_put_path;
667
668 file->private_data = &p->m;
669 ret = seq_open(file, op);
670 if (ret)
671 goto err_free;
672
673 p->m.private = p;
674 p->ns = ns;
675 p->root = root;
676 p->m.poll_event = ns->event;
677
678 return 0;
679
680 err_free:
681 kfree(p);
682 err_put_path:
683 path_put(&root);
684 err_put_ns:
685 put_mnt_ns(ns);
686 err:
687 return ret;
688}
689
690static int mounts_release(struct inode *inode, struct file *file)
691{
692 struct proc_mounts *p = file->private_data;
693 path_put(&p->root);
694 put_mnt_ns(p->ns);
695 return seq_release(inode, file);
696}
697
698static unsigned mounts_poll(struct file *file, poll_table *wait)
699{
700 struct proc_mounts *p = file->private_data;
701 unsigned res = POLLIN | POLLRDNORM;
702
703 poll_wait(file, &p->ns->poll, wait);
704 if (mnt_had_events(p))
705 res |= POLLERR | POLLPRI;
706
707 return res;
708}
709
710static int mounts_open(struct inode *inode, struct file *file)
711{
712 return mounts_open_common(inode, file, &mounts_op);
713}
714
715static const struct file_operations proc_mounts_operations = {
716 .open = mounts_open,
717 .read = seq_read,
718 .llseek = seq_lseek,
719 .release = mounts_release,
720 .poll = mounts_poll,
721};
722
723static int mountinfo_open(struct inode *inode, struct file *file)
724{
725 return mounts_open_common(inode, file, &mountinfo_op);
726}
727
728static const struct file_operations proc_mountinfo_operations = {
729 .open = mountinfo_open,
730 .read = seq_read,
731 .llseek = seq_lseek,
732 .release = mounts_release,
733 .poll = mounts_poll,
734};
735
736static int mountstats_open(struct inode *inode, struct file *file)
737{
738 return mounts_open_common(inode, file, &mountstats_op);
739}
740
741static const struct file_operations proc_mountstats_operations = {
742 .open = mountstats_open,
743 .read = seq_read,
744 .llseek = seq_lseek,
745 .release = mounts_release,
746};
747
748#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
749
750static ssize_t proc_info_read(struct file * file, char __user * buf,
751 size_t count, loff_t *ppos)
752{
753 struct inode * inode = file->f_path.dentry->d_inode;
754 unsigned long page;
755 ssize_t length;
756 struct task_struct *task = get_proc_task(inode);
757
758 length = -ESRCH;
759 if (!task)
760 goto out_no_task;
761
762 if (count > PROC_BLOCK_SIZE)
763 count = PROC_BLOCK_SIZE;
764
765 length = -ENOMEM;
766 if (!(page = __get_free_page(GFP_TEMPORARY)))
767 goto out;
768
769 length = PROC_I(inode)->op.proc_read(task, (char*)page);
770
771 if (length >= 0)
772 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
773 free_page(page);
774out:
775 put_task_struct(task);
776out_no_task:
777 return length;
778}
779
780static const struct file_operations proc_info_file_operations = {
781 .read = proc_info_read,
782 .llseek = generic_file_llseek,
783};
784
785static int proc_single_show(struct seq_file *m, void *v)
786{
787 struct inode *inode = m->private;
788 struct pid_namespace *ns;
789 struct pid *pid;
790 struct task_struct *task;
791 int ret;
792
793 ns = inode->i_sb->s_fs_info;
794 pid = proc_pid(inode);
795 task = get_pid_task(pid, PIDTYPE_PID);
796 if (!task)
797 return -ESRCH;
798
799 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
800
801 put_task_struct(task);
802 return ret;
803}
804
805static int proc_single_open(struct inode *inode, struct file *filp)
806{
807 return single_open(filp, proc_single_show, inode);
808}
809
810static const struct file_operations proc_single_file_operations = {
811 .open = proc_single_open,
812 .read = seq_read,
813 .llseek = seq_lseek,
814 .release = single_release,
815};
816
817static int mem_open(struct inode* inode, struct file* file)
818{
819 file->private_data = (void*)((long)current->self_exec_id);
820 /* OK to pass negative loff_t, we can catch out-of-range */
821 file->f_mode |= FMODE_UNSIGNED_OFFSET;
822 return 0;
823}
824
825static ssize_t mem_read(struct file * file, char __user * buf,
826 size_t count, loff_t *ppos)
827{
828 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
829 char *page;
830 unsigned long src = *ppos;
831 int ret = -ESRCH;
832 struct mm_struct *mm;
833
834 if (!task)
835 goto out_no_task;
836
837 ret = -ENOMEM;
838 page = (char *)__get_free_page(GFP_TEMPORARY);
839 if (!page)
840 goto out;
841
842 mm = check_mem_permission(task);
843 ret = PTR_ERR(mm);
844 if (IS_ERR(mm))
845 goto out_free;
846
847 ret = -EIO;
848
849 if (file->private_data != (void*)((long)current->self_exec_id))
850 goto out_put;
851
852 ret = 0;
853
854 while (count > 0) {
855 int this_len, retval;
856
857 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
858 retval = access_remote_vm(mm, src, page, this_len, 0);
859 if (!retval) {
860 if (!ret)
861 ret = -EIO;
862 break;
863 }
864
865 if (copy_to_user(buf, page, retval)) {
866 ret = -EFAULT;
867 break;
868 }
869
870 ret += retval;
871 src += retval;
872 buf += retval;
873 count -= retval;
874 }
875 *ppos = src;
876
877out_put:
878 mmput(mm);
879out_free:
880 free_page((unsigned long) page);
881out:
882 put_task_struct(task);
883out_no_task:
884 return ret;
885}
886
887static ssize_t mem_write(struct file * file, const char __user *buf,
888 size_t count, loff_t *ppos)
889{
890 int copied;
891 char *page;
892 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
893 unsigned long dst = *ppos;
894 struct mm_struct *mm;
895
896 copied = -ESRCH;
897 if (!task)
898 goto out_no_task;
899
900 copied = -ENOMEM;
901 page = (char *)__get_free_page(GFP_TEMPORARY);
902 if (!page)
903 goto out_task;
904
905 mm = check_mem_permission(task);
906 copied = PTR_ERR(mm);
907 if (IS_ERR(mm))
908 goto out_free;
909
910 copied = -EIO;
911 if (file->private_data != (void *)((long)current->self_exec_id))
912 goto out_mm;
913
914 copied = 0;
915 while (count > 0) {
916 int this_len, retval;
917
918 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
919 if (copy_from_user(page, buf, this_len)) {
920 copied = -EFAULT;
921 break;
922 }
923 retval = access_remote_vm(mm, dst, page, this_len, 1);
924 if (!retval) {
925 if (!copied)
926 copied = -EIO;
927 break;
928 }
929 copied += retval;
930 buf += retval;
931 dst += retval;
932 count -= retval;
933 }
934 *ppos = dst;
935
936out_mm:
937 mmput(mm);
938out_free:
939 free_page((unsigned long) page);
940out_task:
941 put_task_struct(task);
942out_no_task:
943 return copied;
944}
945
946loff_t mem_lseek(struct file *file, loff_t offset, int orig)
947{
948 switch (orig) {
949 case 0:
950 file->f_pos = offset;
951 break;
952 case 1:
953 file->f_pos += offset;
954 break;
955 default:
956 return -EINVAL;
957 }
958 force_successful_syscall_return();
959 return file->f_pos;
960}
961
962static const struct file_operations proc_mem_operations = {
963 .llseek = mem_lseek,
964 .read = mem_read,
965 .write = mem_write,
966 .open = mem_open,
967};
968
969static ssize_t environ_read(struct file *file, char __user *buf,
970 size_t count, loff_t *ppos)
971{
972 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
973 char *page;
974 unsigned long src = *ppos;
975 int ret = -ESRCH;
976 struct mm_struct *mm;
977
978 if (!task)
979 goto out_no_task;
980
981 ret = -ENOMEM;
982 page = (char *)__get_free_page(GFP_TEMPORARY);
983 if (!page)
984 goto out;
985
986
987 mm = mm_for_maps(task);
988 ret = PTR_ERR(mm);
989 if (!mm || IS_ERR(mm))
990 goto out_free;
991
992 ret = 0;
993 while (count > 0) {
994 int this_len, retval, max_len;
995
996 this_len = mm->env_end - (mm->env_start + src);
997
998 if (this_len <= 0)
999 break;
1000
1001 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
1002 this_len = (this_len > max_len) ? max_len : this_len;
1003
1004 retval = access_process_vm(task, (mm->env_start + src),
1005 page, this_len, 0);
1006
1007 if (retval <= 0) {
1008 ret = retval;
1009 break;
1010 }
1011
1012 if (copy_to_user(buf, page, retval)) {
1013 ret = -EFAULT;
1014 break;
1015 }
1016
1017 ret += retval;
1018 src += retval;
1019 buf += retval;
1020 count -= retval;
1021 }
1022 *ppos = src;
1023
1024 mmput(mm);
1025out_free:
1026 free_page((unsigned long) page);
1027out:
1028 put_task_struct(task);
1029out_no_task:
1030 return ret;
1031}
1032
1033static const struct file_operations proc_environ_operations = {
1034 .read = environ_read,
1035 .llseek = generic_file_llseek,
1036};
1037
1038static ssize_t oom_adjust_read(struct file *file, char __user *buf,
1039 size_t count, loff_t *ppos)
1040{
1041 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1042 char buffer[PROC_NUMBUF];
1043 size_t len;
1044 int oom_adjust = OOM_DISABLE;
1045 unsigned long flags;
1046
1047 if (!task)
1048 return -ESRCH;
1049
1050 if (lock_task_sighand(task, &flags)) {
1051 oom_adjust = task->signal->oom_adj;
1052 unlock_task_sighand(task, &flags);
1053 }
1054
1055 put_task_struct(task);
1056
1057 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
1058
1059 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1060}
1061
1062static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
1063 size_t count, loff_t *ppos)
1064{
1065 struct task_struct *task;
1066 char buffer[PROC_NUMBUF];
1067 int oom_adjust;
1068 unsigned long flags;
1069 int err;
1070
1071 memset(buffer, 0, sizeof(buffer));
1072 if (count > sizeof(buffer) - 1)
1073 count = sizeof(buffer) - 1;
1074 if (copy_from_user(buffer, buf, count)) {
1075 err = -EFAULT;
1076 goto out;
1077 }
1078
1079 err = kstrtoint(strstrip(buffer), 0, &oom_adjust);
1080 if (err)
1081 goto out;
1082 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
1083 oom_adjust != OOM_DISABLE) {
1084 err = -EINVAL;
1085 goto out;
1086 }
1087
1088 task = get_proc_task(file->f_path.dentry->d_inode);
1089 if (!task) {
1090 err = -ESRCH;
1091 goto out;
1092 }
1093
1094 task_lock(task);
1095 if (!task->mm) {
1096 err = -EINVAL;
1097 goto err_task_lock;
1098 }
1099
1100 if (!lock_task_sighand(task, &flags)) {
1101 err = -ESRCH;
1102 goto err_task_lock;
1103 }
1104
1105 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
1106 err = -EACCES;
1107 goto err_sighand;
1108 }
1109
1110 if (oom_adjust != task->signal->oom_adj) {
1111 if (oom_adjust == OOM_DISABLE)
1112 atomic_inc(&task->mm->oom_disable_count);
1113 if (task->signal->oom_adj == OOM_DISABLE)
1114 atomic_dec(&task->mm->oom_disable_count);
1115 }
1116
1117 /*
1118 * Warn that /proc/pid/oom_adj is deprecated, see
1119 * Documentation/feature-removal-schedule.txt.
1120 */
1121 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1122 current->comm, task_pid_nr(current), task_pid_nr(task),
1123 task_pid_nr(task));
1124 task->signal->oom_adj = oom_adjust;
1125 /*
1126 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1127 * value is always attainable.
1128 */
1129 if (task->signal->oom_adj == OOM_ADJUST_MAX)
1130 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
1131 else
1132 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
1133 -OOM_DISABLE;
1134err_sighand:
1135 unlock_task_sighand(task, &flags);
1136err_task_lock:
1137 task_unlock(task);
1138 put_task_struct(task);
1139out:
1140 return err < 0 ? err : count;
1141}
1142
1143static const struct file_operations proc_oom_adjust_operations = {
1144 .read = oom_adjust_read,
1145 .write = oom_adjust_write,
1146 .llseek = generic_file_llseek,
1147};
1148
1149static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1150 size_t count, loff_t *ppos)
1151{
1152 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1153 char buffer[PROC_NUMBUF];
1154 int oom_score_adj = OOM_SCORE_ADJ_MIN;
1155 unsigned long flags;
1156 size_t len;
1157
1158 if (!task)
1159 return -ESRCH;
1160 if (lock_task_sighand(task, &flags)) {
1161 oom_score_adj = task->signal->oom_score_adj;
1162 unlock_task_sighand(task, &flags);
1163 }
1164 put_task_struct(task);
1165 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
1166 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1167}
1168
1169static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1170 size_t count, loff_t *ppos)
1171{
1172 struct task_struct *task;
1173 char buffer[PROC_NUMBUF];
1174 unsigned long flags;
1175 int oom_score_adj;
1176 int err;
1177
1178 memset(buffer, 0, sizeof(buffer));
1179 if (count > sizeof(buffer) - 1)
1180 count = sizeof(buffer) - 1;
1181 if (copy_from_user(buffer, buf, count)) {
1182 err = -EFAULT;
1183 goto out;
1184 }
1185
1186 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1187 if (err)
1188 goto out;
1189 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1190 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1191 err = -EINVAL;
1192 goto out;
1193 }
1194
1195 task = get_proc_task(file->f_path.dentry->d_inode);
1196 if (!task) {
1197 err = -ESRCH;
1198 goto out;
1199 }
1200
1201 task_lock(task);
1202 if (!task->mm) {
1203 err = -EINVAL;
1204 goto err_task_lock;
1205 }
1206
1207 if (!lock_task_sighand(task, &flags)) {
1208 err = -ESRCH;
1209 goto err_task_lock;
1210 }
1211
1212 if (oom_score_adj < task->signal->oom_score_adj_min &&
1213 !capable(CAP_SYS_RESOURCE)) {
1214 err = -EACCES;
1215 goto err_sighand;
1216 }
1217
1218 if (oom_score_adj != task->signal->oom_score_adj) {
1219 if (oom_score_adj == OOM_SCORE_ADJ_MIN)
1220 atomic_inc(&task->mm->oom_disable_count);
1221 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1222 atomic_dec(&task->mm->oom_disable_count);
1223 }
1224 task->signal->oom_score_adj = oom_score_adj;
1225 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1226 task->signal->oom_score_adj_min = oom_score_adj;
1227 /*
1228 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1229 * always attainable.
1230 */
1231 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1232 task->signal->oom_adj = OOM_DISABLE;
1233 else
1234 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1235 OOM_SCORE_ADJ_MAX;
1236err_sighand:
1237 unlock_task_sighand(task, &flags);
1238err_task_lock:
1239 task_unlock(task);
1240 put_task_struct(task);
1241out:
1242 return err < 0 ? err : count;
1243}
1244
1245static const struct file_operations proc_oom_score_adj_operations = {
1246 .read = oom_score_adj_read,
1247 .write = oom_score_adj_write,
1248 .llseek = default_llseek,
1249};
1250
1251#ifdef CONFIG_AUDITSYSCALL
1252#define TMPBUFLEN 21
1253static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1254 size_t count, loff_t *ppos)
1255{
1256 struct inode * inode = file->f_path.dentry->d_inode;
1257 struct task_struct *task = get_proc_task(inode);
1258 ssize_t length;
1259 char tmpbuf[TMPBUFLEN];
1260
1261 if (!task)
1262 return -ESRCH;
1263 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1264 audit_get_loginuid(task));
1265 put_task_struct(task);
1266 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1267}
1268
1269static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1270 size_t count, loff_t *ppos)
1271{
1272 struct inode * inode = file->f_path.dentry->d_inode;
1273 char *page, *tmp;
1274 ssize_t length;
1275 uid_t loginuid;
1276
1277 if (!capable(CAP_AUDIT_CONTROL))
1278 return -EPERM;
1279
1280 rcu_read_lock();
1281 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1282 rcu_read_unlock();
1283 return -EPERM;
1284 }
1285 rcu_read_unlock();
1286
1287 if (count >= PAGE_SIZE)
1288 count = PAGE_SIZE - 1;
1289
1290 if (*ppos != 0) {
1291 /* No partial writes. */
1292 return -EINVAL;
1293 }
1294 page = (char*)__get_free_page(GFP_TEMPORARY);
1295 if (!page)
1296 return -ENOMEM;
1297 length = -EFAULT;
1298 if (copy_from_user(page, buf, count))
1299 goto out_free_page;
1300
1301 page[count] = '\0';
1302 loginuid = simple_strtoul(page, &tmp, 10);
1303 if (tmp == page) {
1304 length = -EINVAL;
1305 goto out_free_page;
1306
1307 }
1308 length = audit_set_loginuid(current, loginuid);
1309 if (likely(length == 0))
1310 length = count;
1311
1312out_free_page:
1313 free_page((unsigned long) page);
1314 return length;
1315}
1316
1317static const struct file_operations proc_loginuid_operations = {
1318 .read = proc_loginuid_read,
1319 .write = proc_loginuid_write,
1320 .llseek = generic_file_llseek,
1321};
1322
1323static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1324 size_t count, loff_t *ppos)
1325{
1326 struct inode * inode = file->f_path.dentry->d_inode;
1327 struct task_struct *task = get_proc_task(inode);
1328 ssize_t length;
1329 char tmpbuf[TMPBUFLEN];
1330
1331 if (!task)
1332 return -ESRCH;
1333 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1334 audit_get_sessionid(task));
1335 put_task_struct(task);
1336 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1337}
1338
1339static const struct file_operations proc_sessionid_operations = {
1340 .read = proc_sessionid_read,
1341 .llseek = generic_file_llseek,
1342};
1343#endif
1344
1345#ifdef CONFIG_FAULT_INJECTION
1346static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1347 size_t count, loff_t *ppos)
1348{
1349 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1350 char buffer[PROC_NUMBUF];
1351 size_t len;
1352 int make_it_fail;
1353
1354 if (!task)
1355 return -ESRCH;
1356 make_it_fail = task->make_it_fail;
1357 put_task_struct(task);
1358
1359 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1360
1361 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1362}
1363
1364static ssize_t proc_fault_inject_write(struct file * file,
1365 const char __user * buf, size_t count, loff_t *ppos)
1366{
1367 struct task_struct *task;
1368 char buffer[PROC_NUMBUF], *end;
1369 int make_it_fail;
1370
1371 if (!capable(CAP_SYS_RESOURCE))
1372 return -EPERM;
1373 memset(buffer, 0, sizeof(buffer));
1374 if (count > sizeof(buffer) - 1)
1375 count = sizeof(buffer) - 1;
1376 if (copy_from_user(buffer, buf, count))
1377 return -EFAULT;
1378 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1379 if (*end)
1380 return -EINVAL;
1381 task = get_proc_task(file->f_dentry->d_inode);
1382 if (!task)
1383 return -ESRCH;
1384 task->make_it_fail = make_it_fail;
1385 put_task_struct(task);
1386
1387 return count;
1388}
1389
1390static const struct file_operations proc_fault_inject_operations = {
1391 .read = proc_fault_inject_read,
1392 .write = proc_fault_inject_write,
1393 .llseek = generic_file_llseek,
1394};
1395#endif
1396
1397
1398#ifdef CONFIG_SCHED_DEBUG
1399/*
1400 * Print out various scheduling related per-task fields:
1401 */
1402static int sched_show(struct seq_file *m, void *v)
1403{
1404 struct inode *inode = m->private;
1405 struct task_struct *p;
1406
1407 p = get_proc_task(inode);
1408 if (!p)
1409 return -ESRCH;
1410 proc_sched_show_task(p, m);
1411
1412 put_task_struct(p);
1413
1414 return 0;
1415}
1416
1417static ssize_t
1418sched_write(struct file *file, const char __user *buf,
1419 size_t count, loff_t *offset)
1420{
1421 struct inode *inode = file->f_path.dentry->d_inode;
1422 struct task_struct *p;
1423
1424 p = get_proc_task(inode);
1425 if (!p)
1426 return -ESRCH;
1427 proc_sched_set_task(p);
1428
1429 put_task_struct(p);
1430
1431 return count;
1432}
1433
1434static int sched_open(struct inode *inode, struct file *filp)
1435{
1436 return single_open(filp, sched_show, inode);
1437}
1438
1439static const struct file_operations proc_pid_sched_operations = {
1440 .open = sched_open,
1441 .read = seq_read,
1442 .write = sched_write,
1443 .llseek = seq_lseek,
1444 .release = single_release,
1445};
1446
1447#endif
1448
1449#ifdef CONFIG_SCHED_AUTOGROUP
1450/*
1451 * Print out autogroup related information:
1452 */
1453static int sched_autogroup_show(struct seq_file *m, void *v)
1454{
1455 struct inode *inode = m->private;
1456 struct task_struct *p;
1457
1458 p = get_proc_task(inode);
1459 if (!p)
1460 return -ESRCH;
1461 proc_sched_autogroup_show_task(p, m);
1462
1463 put_task_struct(p);
1464
1465 return 0;
1466}
1467
1468static ssize_t
1469sched_autogroup_write(struct file *file, const char __user *buf,
1470 size_t count, loff_t *offset)
1471{
1472 struct inode *inode = file->f_path.dentry->d_inode;
1473 struct task_struct *p;
1474 char buffer[PROC_NUMBUF];
1475 int nice;
1476 int err;
1477
1478 memset(buffer, 0, sizeof(buffer));
1479 if (count > sizeof(buffer) - 1)
1480 count = sizeof(buffer) - 1;
1481 if (copy_from_user(buffer, buf, count))
1482 return -EFAULT;
1483
1484 err = kstrtoint(strstrip(buffer), 0, &nice);
1485 if (err < 0)
1486 return err;
1487
1488 p = get_proc_task(inode);
1489 if (!p)
1490 return -ESRCH;
1491
1492 err = nice;
1493 err = proc_sched_autogroup_set_nice(p, &err);
1494 if (err)
1495 count = err;
1496
1497 put_task_struct(p);
1498
1499 return count;
1500}
1501
1502static int sched_autogroup_open(struct inode *inode, struct file *filp)
1503{
1504 int ret;
1505
1506 ret = single_open(filp, sched_autogroup_show, NULL);
1507 if (!ret) {
1508 struct seq_file *m = filp->private_data;
1509
1510 m->private = inode;
1511 }
1512 return ret;
1513}
1514
1515static const struct file_operations proc_pid_sched_autogroup_operations = {
1516 .open = sched_autogroup_open,
1517 .read = seq_read,
1518 .write = sched_autogroup_write,
1519 .llseek = seq_lseek,
1520 .release = single_release,
1521};
1522
1523#endif /* CONFIG_SCHED_AUTOGROUP */
1524
1525static ssize_t comm_write(struct file *file, const char __user *buf,
1526 size_t count, loff_t *offset)
1527{
1528 struct inode *inode = file->f_path.dentry->d_inode;
1529 struct task_struct *p;
1530 char buffer[TASK_COMM_LEN];
1531
1532 memset(buffer, 0, sizeof(buffer));
1533 if (count > sizeof(buffer) - 1)
1534 count = sizeof(buffer) - 1;
1535 if (copy_from_user(buffer, buf, count))
1536 return -EFAULT;
1537
1538 p = get_proc_task(inode);
1539 if (!p)
1540 return -ESRCH;
1541
1542 if (same_thread_group(current, p))
1543 set_task_comm(p, buffer);
1544 else
1545 count = -EINVAL;
1546
1547 put_task_struct(p);
1548
1549 return count;
1550}
1551
1552static int comm_show(struct seq_file *m, void *v)
1553{
1554 struct inode *inode = m->private;
1555 struct task_struct *p;
1556
1557 p = get_proc_task(inode);
1558 if (!p)
1559 return -ESRCH;
1560
1561 task_lock(p);
1562 seq_printf(m, "%s\n", p->comm);
1563 task_unlock(p);
1564
1565 put_task_struct(p);
1566
1567 return 0;
1568}
1569
1570static int comm_open(struct inode *inode, struct file *filp)
1571{
1572 return single_open(filp, comm_show, inode);
1573}
1574
1575static const struct file_operations proc_pid_set_comm_operations = {
1576 .open = comm_open,
1577 .read = seq_read,
1578 .write = comm_write,
1579 .llseek = seq_lseek,
1580 .release = single_release,
1581};
1582
1583static int proc_exe_link(struct inode *inode, struct path *exe_path)
1584{
1585 struct task_struct *task;
1586 struct mm_struct *mm;
1587 struct file *exe_file;
1588
1589 task = get_proc_task(inode);
1590 if (!task)
1591 return -ENOENT;
1592 mm = get_task_mm(task);
1593 put_task_struct(task);
1594 if (!mm)
1595 return -ENOENT;
1596 exe_file = get_mm_exe_file(mm);
1597 mmput(mm);
1598 if (exe_file) {
1599 *exe_path = exe_file->f_path;
1600 path_get(&exe_file->f_path);
1601 fput(exe_file);
1602 return 0;
1603 } else
1604 return -ENOENT;
1605}
1606
1607static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1608{
1609 struct inode *inode = dentry->d_inode;
1610 int error = -EACCES;
1611
1612 /* We don't need a base pointer in the /proc filesystem */
1613 path_put(&nd->path);
1614
1615 /* Are we allowed to snoop on the tasks file descriptors? */
1616 if (!proc_fd_access_allowed(inode))
1617 goto out;
1618
1619 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
1620out:
1621 return ERR_PTR(error);
1622}
1623
1624static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1625{
1626 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
1627 char *pathname;
1628 int len;
1629
1630 if (!tmp)
1631 return -ENOMEM;
1632
1633 pathname = d_path(path, tmp, PAGE_SIZE);
1634 len = PTR_ERR(pathname);
1635 if (IS_ERR(pathname))
1636 goto out;
1637 len = tmp + PAGE_SIZE - 1 - pathname;
1638
1639 if (len > buflen)
1640 len = buflen;
1641 if (copy_to_user(buffer, pathname, len))
1642 len = -EFAULT;
1643 out:
1644 free_page((unsigned long)tmp);
1645 return len;
1646}
1647
1648static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1649{
1650 int error = -EACCES;
1651 struct inode *inode = dentry->d_inode;
1652 struct path path;
1653
1654 /* Are we allowed to snoop on the tasks file descriptors? */
1655 if (!proc_fd_access_allowed(inode))
1656 goto out;
1657
1658 error = PROC_I(inode)->op.proc_get_link(inode, &path);
1659 if (error)
1660 goto out;
1661
1662 error = do_proc_readlink(&path, buffer, buflen);
1663 path_put(&path);
1664out:
1665 return error;
1666}
1667
1668static const struct inode_operations proc_pid_link_inode_operations = {
1669 .readlink = proc_pid_readlink,
1670 .follow_link = proc_pid_follow_link,
1671 .setattr = proc_setattr,
1672};
1673
1674
1675/* building an inode */
1676
1677static int task_dumpable(struct task_struct *task)
1678{
1679 int dumpable = 0;
1680 struct mm_struct *mm;
1681
1682 task_lock(task);
1683 mm = task->mm;
1684 if (mm)
1685 dumpable = get_dumpable(mm);
1686 task_unlock(task);
1687 if(dumpable == 1)
1688 return 1;
1689 return 0;
1690}
1691
1692struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
1693{
1694 struct inode * inode;
1695 struct proc_inode *ei;
1696 const struct cred *cred;
1697
1698 /* We need a new inode */
1699
1700 inode = new_inode(sb);
1701 if (!inode)
1702 goto out;
1703
1704 /* Common stuff */
1705 ei = PROC_I(inode);
1706 inode->i_ino = get_next_ino();
1707 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1708 inode->i_op = &proc_def_inode_operations;
1709
1710 /*
1711 * grab the reference to task.
1712 */
1713 ei->pid = get_task_pid(task, PIDTYPE_PID);
1714 if (!ei->pid)
1715 goto out_unlock;
1716
1717 if (task_dumpable(task)) {
1718 rcu_read_lock();
1719 cred = __task_cred(task);
1720 inode->i_uid = cred->euid;
1721 inode->i_gid = cred->egid;
1722 rcu_read_unlock();
1723 }
1724 security_task_to_inode(task, inode);
1725
1726out:
1727 return inode;
1728
1729out_unlock:
1730 iput(inode);
1731 return NULL;
1732}
1733
1734int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1735{
1736 struct inode *inode = dentry->d_inode;
1737 struct task_struct *task;
1738 const struct cred *cred;
1739
1740 generic_fillattr(inode, stat);
1741
1742 rcu_read_lock();
1743 stat->uid = 0;
1744 stat->gid = 0;
1745 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1746 if (task) {
1747 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1748 task_dumpable(task)) {
1749 cred = __task_cred(task);
1750 stat->uid = cred->euid;
1751 stat->gid = cred->egid;
1752 }
1753 }
1754 rcu_read_unlock();
1755 return 0;
1756}
1757
1758/* dentry stuff */
1759
1760/*
1761 * Exceptional case: normally we are not allowed to unhash a busy
1762 * directory. In this case, however, we can do it - no aliasing problems
1763 * due to the way we treat inodes.
1764 *
1765 * Rewrite the inode's ownerships here because the owning task may have
1766 * performed a setuid(), etc.
1767 *
1768 * Before the /proc/pid/status file was created the only way to read
1769 * the effective uid of a /process was to stat /proc/pid. Reading
1770 * /proc/pid/status is slow enough that procps and other packages
1771 * kept stating /proc/pid. To keep the rules in /proc simple I have
1772 * made this apply to all per process world readable and executable
1773 * directories.
1774 */
1775int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1776{
1777 struct inode *inode;
1778 struct task_struct *task;
1779 const struct cred *cred;
1780
1781 if (nd && nd->flags & LOOKUP_RCU)
1782 return -ECHILD;
1783
1784 inode = dentry->d_inode;
1785 task = get_proc_task(inode);
1786
1787 if (task) {
1788 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1789 task_dumpable(task)) {
1790 rcu_read_lock();
1791 cred = __task_cred(task);
1792 inode->i_uid = cred->euid;
1793 inode->i_gid = cred->egid;
1794 rcu_read_unlock();
1795 } else {
1796 inode->i_uid = 0;
1797 inode->i_gid = 0;
1798 }
1799 inode->i_mode &= ~(S_ISUID | S_ISGID);
1800 security_task_to_inode(task, inode);
1801 put_task_struct(task);
1802 return 1;
1803 }
1804 d_drop(dentry);
1805 return 0;
1806}
1807
1808static int pid_delete_dentry(const struct dentry * dentry)
1809{
1810 /* Is the task we represent dead?
1811 * If so, then don't put the dentry on the lru list,
1812 * kill it immediately.
1813 */
1814 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1815}
1816
1817const struct dentry_operations pid_dentry_operations =
1818{
1819 .d_revalidate = pid_revalidate,
1820 .d_delete = pid_delete_dentry,
1821};
1822
1823/* Lookups */
1824
1825/*
1826 * Fill a directory entry.
1827 *
1828 * If possible create the dcache entry and derive our inode number and
1829 * file type from dcache entry.
1830 *
1831 * Since all of the proc inode numbers are dynamically generated, the inode
1832 * numbers do not exist until the inode is cache. This means creating the
1833 * the dcache entry in readdir is necessary to keep the inode numbers
1834 * reported by readdir in sync with the inode numbers reported
1835 * by stat.
1836 */
1837int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1838 const char *name, int len,
1839 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1840{
1841 struct dentry *child, *dir = filp->f_path.dentry;
1842 struct inode *inode;
1843 struct qstr qname;
1844 ino_t ino = 0;
1845 unsigned type = DT_UNKNOWN;
1846
1847 qname.name = name;
1848 qname.len = len;
1849 qname.hash = full_name_hash(name, len);
1850
1851 child = d_lookup(dir, &qname);
1852 if (!child) {
1853 struct dentry *new;
1854 new = d_alloc(dir, &qname);
1855 if (new) {
1856 child = instantiate(dir->d_inode, new, task, ptr);
1857 if (child)
1858 dput(new);
1859 else
1860 child = new;
1861 }
1862 }
1863 if (!child || IS_ERR(child) || !child->d_inode)
1864 goto end_instantiate;
1865 inode = child->d_inode;
1866 if (inode) {
1867 ino = inode->i_ino;
1868 type = inode->i_mode >> 12;
1869 }
1870 dput(child);
1871end_instantiate:
1872 if (!ino)
1873 ino = find_inode_number(dir, &qname);
1874 if (!ino)
1875 ino = 1;
1876 return filldir(dirent, name, len, filp->f_pos, ino, type);
1877}
1878
1879static unsigned name_to_int(struct dentry *dentry)
1880{
1881 const char *name = dentry->d_name.name;
1882 int len = dentry->d_name.len;
1883 unsigned n = 0;
1884
1885 if (len > 1 && *name == '0')
1886 goto out;
1887 while (len-- > 0) {
1888 unsigned c = *name++ - '0';
1889 if (c > 9)
1890 goto out;
1891 if (n >= (~0U-9)/10)
1892 goto out;
1893 n *= 10;
1894 n += c;
1895 }
1896 return n;
1897out:
1898 return ~0U;
1899}
1900
1901#define PROC_FDINFO_MAX 64
1902
1903static int proc_fd_info(struct inode *inode, struct path *path, char *info)
1904{
1905 struct task_struct *task = get_proc_task(inode);
1906 struct files_struct *files = NULL;
1907 struct file *file;
1908 int fd = proc_fd(inode);
1909
1910 if (task) {
1911 files = get_files_struct(task);
1912 put_task_struct(task);
1913 }
1914 if (files) {
1915 /*
1916 * We are not taking a ref to the file structure, so we must
1917 * hold ->file_lock.
1918 */
1919 spin_lock(&files->file_lock);
1920 file = fcheck_files(files, fd);
1921 if (file) {
1922 unsigned int f_flags;
1923 struct fdtable *fdt;
1924
1925 fdt = files_fdtable(files);
1926 f_flags = file->f_flags & ~O_CLOEXEC;
1927 if (FD_ISSET(fd, fdt->close_on_exec))
1928 f_flags |= O_CLOEXEC;
1929
1930 if (path) {
1931 *path = file->f_path;
1932 path_get(&file->f_path);
1933 }
1934 if (info)
1935 snprintf(info, PROC_FDINFO_MAX,
1936 "pos:\t%lli\n"
1937 "flags:\t0%o\n",
1938 (long long) file->f_pos,
1939 f_flags);
1940 spin_unlock(&files->file_lock);
1941 put_files_struct(files);
1942 return 0;
1943 }
1944 spin_unlock(&files->file_lock);
1945 put_files_struct(files);
1946 }
1947 return -ENOENT;
1948}
1949
1950static int proc_fd_link(struct inode *inode, struct path *path)
1951{
1952 return proc_fd_info(inode, path, NULL);
1953}
1954
1955static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1956{
1957 struct inode *inode;
1958 struct task_struct *task;
1959 int fd;
1960 struct files_struct *files;
1961 const struct cred *cred;
1962
1963 if (nd && nd->flags & LOOKUP_RCU)
1964 return -ECHILD;
1965
1966 inode = dentry->d_inode;
1967 task = get_proc_task(inode);
1968 fd = proc_fd(inode);
1969
1970 if (task) {
1971 files = get_files_struct(task);
1972 if (files) {
1973 rcu_read_lock();
1974 if (fcheck_files(files, fd)) {
1975 rcu_read_unlock();
1976 put_files_struct(files);
1977 if (task_dumpable(task)) {
1978 rcu_read_lock();
1979 cred = __task_cred(task);
1980 inode->i_uid = cred->euid;
1981 inode->i_gid = cred->egid;
1982 rcu_read_unlock();
1983 } else {
1984 inode->i_uid = 0;
1985 inode->i_gid = 0;
1986 }
1987 inode->i_mode &= ~(S_ISUID | S_ISGID);
1988 security_task_to_inode(task, inode);
1989 put_task_struct(task);
1990 return 1;
1991 }
1992 rcu_read_unlock();
1993 put_files_struct(files);
1994 }
1995 put_task_struct(task);
1996 }
1997 d_drop(dentry);
1998 return 0;
1999}
2000
2001static const struct dentry_operations tid_fd_dentry_operations =
2002{
2003 .d_revalidate = tid_fd_revalidate,
2004 .d_delete = pid_delete_dentry,
2005};
2006
2007static struct dentry *proc_fd_instantiate(struct inode *dir,
2008 struct dentry *dentry, struct task_struct *task, const void *ptr)
2009{
2010 unsigned fd = *(const unsigned *)ptr;
2011 struct file *file;
2012 struct files_struct *files;
2013 struct inode *inode;
2014 struct proc_inode *ei;
2015 struct dentry *error = ERR_PTR(-ENOENT);
2016
2017 inode = proc_pid_make_inode(dir->i_sb, task);
2018 if (!inode)
2019 goto out;
2020 ei = PROC_I(inode);
2021 ei->fd = fd;
2022 files = get_files_struct(task);
2023 if (!files)
2024 goto out_iput;
2025 inode->i_mode = S_IFLNK;
2026
2027 /*
2028 * We are not taking a ref to the file structure, so we must
2029 * hold ->file_lock.
2030 */
2031 spin_lock(&files->file_lock);
2032 file = fcheck_files(files, fd);
2033 if (!file)
2034 goto out_unlock;
2035 if (file->f_mode & FMODE_READ)
2036 inode->i_mode |= S_IRUSR | S_IXUSR;
2037 if (file->f_mode & FMODE_WRITE)
2038 inode->i_mode |= S_IWUSR | S_IXUSR;
2039 spin_unlock(&files->file_lock);
2040 put_files_struct(files);
2041
2042 inode->i_op = &proc_pid_link_inode_operations;
2043 inode->i_size = 64;
2044 ei->op.proc_get_link = proc_fd_link;
2045 d_set_d_op(dentry, &tid_fd_dentry_operations);
2046 d_add(dentry, inode);
2047 /* Close the race of the process dying before we return the dentry */
2048 if (tid_fd_revalidate(dentry, NULL))
2049 error = NULL;
2050
2051 out:
2052 return error;
2053out_unlock:
2054 spin_unlock(&files->file_lock);
2055 put_files_struct(files);
2056out_iput:
2057 iput(inode);
2058 goto out;
2059}
2060
2061static struct dentry *proc_lookupfd_common(struct inode *dir,
2062 struct dentry *dentry,
2063 instantiate_t instantiate)
2064{
2065 struct task_struct *task = get_proc_task(dir);
2066 unsigned fd = name_to_int(dentry);
2067 struct dentry *result = ERR_PTR(-ENOENT);
2068
2069 if (!task)
2070 goto out_no_task;
2071 if (fd == ~0U)
2072 goto out;
2073
2074 result = instantiate(dir, dentry, task, &fd);
2075out:
2076 put_task_struct(task);
2077out_no_task:
2078 return result;
2079}
2080
2081static int proc_readfd_common(struct file * filp, void * dirent,
2082 filldir_t filldir, instantiate_t instantiate)
2083{
2084 struct dentry *dentry = filp->f_path.dentry;
2085 struct inode *inode = dentry->d_inode;
2086 struct task_struct *p = get_proc_task(inode);
2087 unsigned int fd, ino;
2088 int retval;
2089 struct files_struct * files;
2090
2091 retval = -ENOENT;
2092 if (!p)
2093 goto out_no_task;
2094 retval = 0;
2095
2096 fd = filp->f_pos;
2097 switch (fd) {
2098 case 0:
2099 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
2100 goto out;
2101 filp->f_pos++;
2102 case 1:
2103 ino = parent_ino(dentry);
2104 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2105 goto out;
2106 filp->f_pos++;
2107 default:
2108 files = get_files_struct(p);
2109 if (!files)
2110 goto out;
2111 rcu_read_lock();
2112 for (fd = filp->f_pos-2;
2113 fd < files_fdtable(files)->max_fds;
2114 fd++, filp->f_pos++) {
2115 char name[PROC_NUMBUF];
2116 int len;
2117
2118 if (!fcheck_files(files, fd))
2119 continue;
2120 rcu_read_unlock();
2121
2122 len = snprintf(name, sizeof(name), "%d", fd);
2123 if (proc_fill_cache(filp, dirent, filldir,
2124 name, len, instantiate,
2125 p, &fd) < 0) {
2126 rcu_read_lock();
2127 break;
2128 }
2129 rcu_read_lock();
2130 }
2131 rcu_read_unlock();
2132 put_files_struct(files);
2133 }
2134out:
2135 put_task_struct(p);
2136out_no_task:
2137 return retval;
2138}
2139
2140static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
2141 struct nameidata *nd)
2142{
2143 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
2144}
2145
2146static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
2147{
2148 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
2149}
2150
2151static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
2152 size_t len, loff_t *ppos)
2153{
2154 char tmp[PROC_FDINFO_MAX];
2155 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
2156 if (!err)
2157 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
2158 return err;
2159}
2160
2161static const struct file_operations proc_fdinfo_file_operations = {
2162 .open = nonseekable_open,
2163 .read = proc_fdinfo_read,
2164 .llseek = no_llseek,
2165};
2166
2167static const struct file_operations proc_fd_operations = {
2168 .read = generic_read_dir,
2169 .readdir = proc_readfd,
2170 .llseek = default_llseek,
2171};
2172
2173/*
2174 * /proc/pid/fd needs a special permission handler so that a process can still
2175 * access /proc/self/fd after it has executed a setuid().
2176 */
2177static int proc_fd_permission(struct inode *inode, int mask)
2178{
2179 int rv = generic_permission(inode, mask);
2180 if (rv == 0)
2181 return 0;
2182 if (task_pid(current) == proc_pid(inode))
2183 rv = 0;
2184 return rv;
2185}
2186
2187/*
2188 * proc directories can do almost nothing..
2189 */
2190static const struct inode_operations proc_fd_inode_operations = {
2191 .lookup = proc_lookupfd,
2192 .permission = proc_fd_permission,
2193 .setattr = proc_setattr,
2194};
2195
2196static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2197 struct dentry *dentry, struct task_struct *task, const void *ptr)
2198{
2199 unsigned fd = *(unsigned *)ptr;
2200 struct inode *inode;
2201 struct proc_inode *ei;
2202 struct dentry *error = ERR_PTR(-ENOENT);
2203
2204 inode = proc_pid_make_inode(dir->i_sb, task);
2205 if (!inode)
2206 goto out;
2207 ei = PROC_I(inode);
2208 ei->fd = fd;
2209 inode->i_mode = S_IFREG | S_IRUSR;
2210 inode->i_fop = &proc_fdinfo_file_operations;
2211 d_set_d_op(dentry, &tid_fd_dentry_operations);
2212 d_add(dentry, inode);
2213 /* Close the race of the process dying before we return the dentry */
2214 if (tid_fd_revalidate(dentry, NULL))
2215 error = NULL;
2216
2217 out:
2218 return error;
2219}
2220
2221static struct dentry *proc_lookupfdinfo(struct inode *dir,
2222 struct dentry *dentry,
2223 struct nameidata *nd)
2224{
2225 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2226}
2227
2228static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2229{
2230 return proc_readfd_common(filp, dirent, filldir,
2231 proc_fdinfo_instantiate);
2232}
2233
2234static const struct file_operations proc_fdinfo_operations = {
2235 .read = generic_read_dir,
2236 .readdir = proc_readfdinfo,
2237 .llseek = default_llseek,
2238};
2239
2240/*
2241 * proc directories can do almost nothing..
2242 */
2243static const struct inode_operations proc_fdinfo_inode_operations = {
2244 .lookup = proc_lookupfdinfo,
2245 .setattr = proc_setattr,
2246};
2247
2248
2249static struct dentry *proc_pident_instantiate(struct inode *dir,
2250 struct dentry *dentry, struct task_struct *task, const void *ptr)
2251{
2252 const struct pid_entry *p = ptr;
2253 struct inode *inode;
2254 struct proc_inode *ei;
2255 struct dentry *error = ERR_PTR(-ENOENT);
2256
2257 inode = proc_pid_make_inode(dir->i_sb, task);
2258 if (!inode)
2259 goto out;
2260
2261 ei = PROC_I(inode);
2262 inode->i_mode = p->mode;
2263 if (S_ISDIR(inode->i_mode))
2264 inode->i_nlink = 2; /* Use getattr to fix if necessary */
2265 if (p->iop)
2266 inode->i_op = p->iop;
2267 if (p->fop)
2268 inode->i_fop = p->fop;
2269 ei->op = p->op;
2270 d_set_d_op(dentry, &pid_dentry_operations);
2271 d_add(dentry, inode);
2272 /* Close the race of the process dying before we return the dentry */
2273 if (pid_revalidate(dentry, NULL))
2274 error = NULL;
2275out:
2276 return error;
2277}
2278
2279static struct dentry *proc_pident_lookup(struct inode *dir,
2280 struct dentry *dentry,
2281 const struct pid_entry *ents,
2282 unsigned int nents)
2283{
2284 struct dentry *error;
2285 struct task_struct *task = get_proc_task(dir);
2286 const struct pid_entry *p, *last;
2287
2288 error = ERR_PTR(-ENOENT);
2289
2290 if (!task)
2291 goto out_no_task;
2292
2293 /*
2294 * Yes, it does not scale. And it should not. Don't add
2295 * new entries into /proc/<tgid>/ without very good reasons.
2296 */
2297 last = &ents[nents - 1];
2298 for (p = ents; p <= last; p++) {
2299 if (p->len != dentry->d_name.len)
2300 continue;
2301 if (!memcmp(dentry->d_name.name, p->name, p->len))
2302 break;
2303 }
2304 if (p > last)
2305 goto out;
2306
2307 error = proc_pident_instantiate(dir, dentry, task, p);
2308out:
2309 put_task_struct(task);
2310out_no_task:
2311 return error;
2312}
2313
2314static int proc_pident_fill_cache(struct file *filp, void *dirent,
2315 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2316{
2317 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2318 proc_pident_instantiate, task, p);
2319}
2320
2321static int proc_pident_readdir(struct file *filp,
2322 void *dirent, filldir_t filldir,
2323 const struct pid_entry *ents, unsigned int nents)
2324{
2325 int i;
2326 struct dentry *dentry = filp->f_path.dentry;
2327 struct inode *inode = dentry->d_inode;
2328 struct task_struct *task = get_proc_task(inode);
2329 const struct pid_entry *p, *last;
2330 ino_t ino;
2331 int ret;
2332
2333 ret = -ENOENT;
2334 if (!task)
2335 goto out_no_task;
2336
2337 ret = 0;
2338 i = filp->f_pos;
2339 switch (i) {
2340 case 0:
2341 ino = inode->i_ino;
2342 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2343 goto out;
2344 i++;
2345 filp->f_pos++;
2346 /* fall through */
2347 case 1:
2348 ino = parent_ino(dentry);
2349 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2350 goto out;
2351 i++;
2352 filp->f_pos++;
2353 /* fall through */
2354 default:
2355 i -= 2;
2356 if (i >= nents) {
2357 ret = 1;
2358 goto out;
2359 }
2360 p = ents + i;
2361 last = &ents[nents - 1];
2362 while (p <= last) {
2363 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
2364 goto out;
2365 filp->f_pos++;
2366 p++;
2367 }
2368 }
2369
2370 ret = 1;
2371out:
2372 put_task_struct(task);
2373out_no_task:
2374 return ret;
2375}
2376
2377#ifdef CONFIG_SECURITY
2378static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2379 size_t count, loff_t *ppos)
2380{
2381 struct inode * inode = file->f_path.dentry->d_inode;
2382 char *p = NULL;
2383 ssize_t length;
2384 struct task_struct *task = get_proc_task(inode);
2385
2386 if (!task)
2387 return -ESRCH;
2388
2389 length = security_getprocattr(task,
2390 (char*)file->f_path.dentry->d_name.name,
2391 &p);
2392 put_task_struct(task);
2393 if (length > 0)
2394 length = simple_read_from_buffer(buf, count, ppos, p, length);
2395 kfree(p);
2396 return length;
2397}
2398
2399static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2400 size_t count, loff_t *ppos)
2401{
2402 struct inode * inode = file->f_path.dentry->d_inode;
2403 char *page;
2404 ssize_t length;
2405 struct task_struct *task = get_proc_task(inode);
2406
2407 length = -ESRCH;
2408 if (!task)
2409 goto out_no_task;
2410 if (count > PAGE_SIZE)
2411 count = PAGE_SIZE;
2412
2413 /* No partial writes. */
2414 length = -EINVAL;
2415 if (*ppos != 0)
2416 goto out;
2417
2418 length = -ENOMEM;
2419 page = (char*)__get_free_page(GFP_TEMPORARY);
2420 if (!page)
2421 goto out;
2422
2423 length = -EFAULT;
2424 if (copy_from_user(page, buf, count))
2425 goto out_free;
2426
2427 /* Guard against adverse ptrace interaction */
2428 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
2429 if (length < 0)
2430 goto out_free;
2431
2432 length = security_setprocattr(task,
2433 (char*)file->f_path.dentry->d_name.name,
2434 (void*)page, count);
2435 mutex_unlock(&task->signal->cred_guard_mutex);
2436out_free:
2437 free_page((unsigned long) page);
2438out:
2439 put_task_struct(task);
2440out_no_task:
2441 return length;
2442}
2443
2444static const struct file_operations proc_pid_attr_operations = {
2445 .read = proc_pid_attr_read,
2446 .write = proc_pid_attr_write,
2447 .llseek = generic_file_llseek,
2448};
2449
2450static const struct pid_entry attr_dir_stuff[] = {
2451 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2452 REG("prev", S_IRUGO, proc_pid_attr_operations),
2453 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2454 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2455 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2456 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2457};
2458
2459static int proc_attr_dir_readdir(struct file * filp,
2460 void * dirent, filldir_t filldir)
2461{
2462 return proc_pident_readdir(filp,dirent,filldir,
2463 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
2464}
2465
2466static const struct file_operations proc_attr_dir_operations = {
2467 .read = generic_read_dir,
2468 .readdir = proc_attr_dir_readdir,
2469 .llseek = default_llseek,
2470};
2471
2472static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2473 struct dentry *dentry, struct nameidata *nd)
2474{
2475 return proc_pident_lookup(dir, dentry,
2476 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2477}
2478
2479static const struct inode_operations proc_attr_dir_inode_operations = {
2480 .lookup = proc_attr_dir_lookup,
2481 .getattr = pid_getattr,
2482 .setattr = proc_setattr,
2483};
2484
2485#endif
2486
2487#ifdef CONFIG_ELF_CORE
2488static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2489 size_t count, loff_t *ppos)
2490{
2491 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2492 struct mm_struct *mm;
2493 char buffer[PROC_NUMBUF];
2494 size_t len;
2495 int ret;
2496
2497 if (!task)
2498 return -ESRCH;
2499
2500 ret = 0;
2501 mm = get_task_mm(task);
2502 if (mm) {
2503 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2504 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2505 MMF_DUMP_FILTER_SHIFT));
2506 mmput(mm);
2507 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2508 }
2509
2510 put_task_struct(task);
2511
2512 return ret;
2513}
2514
2515static ssize_t proc_coredump_filter_write(struct file *file,
2516 const char __user *buf,
2517 size_t count,
2518 loff_t *ppos)
2519{
2520 struct task_struct *task;
2521 struct mm_struct *mm;
2522 char buffer[PROC_NUMBUF], *end;
2523 unsigned int val;
2524 int ret;
2525 int i;
2526 unsigned long mask;
2527
2528 ret = -EFAULT;
2529 memset(buffer, 0, sizeof(buffer));
2530 if (count > sizeof(buffer) - 1)
2531 count = sizeof(buffer) - 1;
2532 if (copy_from_user(buffer, buf, count))
2533 goto out_no_task;
2534
2535 ret = -EINVAL;
2536 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2537 if (*end == '\n')
2538 end++;
2539 if (end - buffer == 0)
2540 goto out_no_task;
2541
2542 ret = -ESRCH;
2543 task = get_proc_task(file->f_dentry->d_inode);
2544 if (!task)
2545 goto out_no_task;
2546
2547 ret = end - buffer;
2548 mm = get_task_mm(task);
2549 if (!mm)
2550 goto out_no_mm;
2551
2552 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2553 if (val & mask)
2554 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2555 else
2556 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2557 }
2558
2559 mmput(mm);
2560 out_no_mm:
2561 put_task_struct(task);
2562 out_no_task:
2563 return ret;
2564}
2565
2566static const struct file_operations proc_coredump_filter_operations = {
2567 .read = proc_coredump_filter_read,
2568 .write = proc_coredump_filter_write,
2569 .llseek = generic_file_llseek,
2570};
2571#endif
2572
2573/*
2574 * /proc/self:
2575 */
2576static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2577 int buflen)
2578{
2579 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2580 pid_t tgid = task_tgid_nr_ns(current, ns);
2581 char tmp[PROC_NUMBUF];
2582 if (!tgid)
2583 return -ENOENT;
2584 sprintf(tmp, "%d", tgid);
2585 return vfs_readlink(dentry,buffer,buflen,tmp);
2586}
2587
2588static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2589{
2590 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2591 pid_t tgid = task_tgid_nr_ns(current, ns);
2592 char *name = ERR_PTR(-ENOENT);
2593 if (tgid) {
2594 name = __getname();
2595 if (!name)
2596 name = ERR_PTR(-ENOMEM);
2597 else
2598 sprintf(name, "%d", tgid);
2599 }
2600 nd_set_link(nd, name);
2601 return NULL;
2602}
2603
2604static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2605 void *cookie)
2606{
2607 char *s = nd_get_link(nd);
2608 if (!IS_ERR(s))
2609 __putname(s);
2610}
2611
2612static const struct inode_operations proc_self_inode_operations = {
2613 .readlink = proc_self_readlink,
2614 .follow_link = proc_self_follow_link,
2615 .put_link = proc_self_put_link,
2616};
2617
2618/*
2619 * proc base
2620 *
2621 * These are the directory entries in the root directory of /proc
2622 * that properly belong to the /proc filesystem, as they describe
2623 * describe something that is process related.
2624 */
2625static const struct pid_entry proc_base_stuff[] = {
2626 NOD("self", S_IFLNK|S_IRWXUGO,
2627 &proc_self_inode_operations, NULL, {}),
2628};
2629
2630static struct dentry *proc_base_instantiate(struct inode *dir,
2631 struct dentry *dentry, struct task_struct *task, const void *ptr)
2632{
2633 const struct pid_entry *p = ptr;
2634 struct inode *inode;
2635 struct proc_inode *ei;
2636 struct dentry *error;
2637
2638 /* Allocate the inode */
2639 error = ERR_PTR(-ENOMEM);
2640 inode = new_inode(dir->i_sb);
2641 if (!inode)
2642 goto out;
2643
2644 /* Initialize the inode */
2645 ei = PROC_I(inode);
2646 inode->i_ino = get_next_ino();
2647 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2648
2649 /*
2650 * grab the reference to the task.
2651 */
2652 ei->pid = get_task_pid(task, PIDTYPE_PID);
2653 if (!ei->pid)
2654 goto out_iput;
2655
2656 inode->i_mode = p->mode;
2657 if (S_ISDIR(inode->i_mode))
2658 inode->i_nlink = 2;
2659 if (S_ISLNK(inode->i_mode))
2660 inode->i_size = 64;
2661 if (p->iop)
2662 inode->i_op = p->iop;
2663 if (p->fop)
2664 inode->i_fop = p->fop;
2665 ei->op = p->op;
2666 d_add(dentry, inode);
2667 error = NULL;
2668out:
2669 return error;
2670out_iput:
2671 iput(inode);
2672 goto out;
2673}
2674
2675static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2676{
2677 struct dentry *error;
2678 struct task_struct *task = get_proc_task(dir);
2679 const struct pid_entry *p, *last;
2680
2681 error = ERR_PTR(-ENOENT);
2682
2683 if (!task)
2684 goto out_no_task;
2685
2686 /* Lookup the directory entry */
2687 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2688 for (p = proc_base_stuff; p <= last; p++) {
2689 if (p->len != dentry->d_name.len)
2690 continue;
2691 if (!memcmp(dentry->d_name.name, p->name, p->len))
2692 break;
2693 }
2694 if (p > last)
2695 goto out;
2696
2697 error = proc_base_instantiate(dir, dentry, task, p);
2698
2699out:
2700 put_task_struct(task);
2701out_no_task:
2702 return error;
2703}
2704
2705static int proc_base_fill_cache(struct file *filp, void *dirent,
2706 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2707{
2708 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2709 proc_base_instantiate, task, p);
2710}
2711
2712#ifdef CONFIG_TASK_IO_ACCOUNTING
2713static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2714{
2715 struct task_io_accounting acct = task->ioac;
2716 unsigned long flags;
2717 int result;
2718
2719 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2720 if (result)
2721 return result;
2722
2723 if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
2724 result = -EACCES;
2725 goto out_unlock;
2726 }
2727
2728 if (whole && lock_task_sighand(task, &flags)) {
2729 struct task_struct *t = task;
2730
2731 task_io_accounting_add(&acct, &task->signal->ioac);
2732 while_each_thread(task, t)
2733 task_io_accounting_add(&acct, &t->ioac);
2734
2735 unlock_task_sighand(task, &flags);
2736 }
2737 result = sprintf(buffer,
2738 "rchar: %llu\n"
2739 "wchar: %llu\n"
2740 "syscr: %llu\n"
2741 "syscw: %llu\n"
2742 "read_bytes: %llu\n"
2743 "write_bytes: %llu\n"
2744 "cancelled_write_bytes: %llu\n",
2745 (unsigned long long)acct.rchar,
2746 (unsigned long long)acct.wchar,
2747 (unsigned long long)acct.syscr,
2748 (unsigned long long)acct.syscw,
2749 (unsigned long long)acct.read_bytes,
2750 (unsigned long long)acct.write_bytes,
2751 (unsigned long long)acct.cancelled_write_bytes);
2752out_unlock:
2753 mutex_unlock(&task->signal->cred_guard_mutex);
2754 return result;
2755}
2756
2757static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2758{
2759 return do_io_accounting(task, buffer, 0);
2760}
2761
2762static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2763{
2764 return do_io_accounting(task, buffer, 1);
2765}
2766#endif /* CONFIG_TASK_IO_ACCOUNTING */
2767
2768static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2769 struct pid *pid, struct task_struct *task)
2770{
2771 int err = lock_trace(task);
2772 if (!err) {
2773 seq_printf(m, "%08x\n", task->personality);
2774 unlock_trace(task);
2775 }
2776 return err;
2777}
2778
2779/*
2780 * Thread groups
2781 */
2782static const struct file_operations proc_task_operations;
2783static const struct inode_operations proc_task_inode_operations;
2784
2785static const struct pid_entry tgid_base_stuff[] = {
2786 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2787 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2788 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2789 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
2790#ifdef CONFIG_NET
2791 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
2792#endif
2793 REG("environ", S_IRUSR, proc_environ_operations),
2794 INF("auxv", S_IRUSR, proc_pid_auxv),
2795 ONE("status", S_IRUGO, proc_pid_status),
2796 ONE("personality", S_IRUGO, proc_pid_personality),
2797 INF("limits", S_IRUGO, proc_pid_limits),
2798#ifdef CONFIG_SCHED_DEBUG
2799 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2800#endif
2801#ifdef CONFIG_SCHED_AUTOGROUP
2802 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
2803#endif
2804 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2805#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2806 INF("syscall", S_IRUGO, proc_pid_syscall),
2807#endif
2808 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2809 ONE("stat", S_IRUGO, proc_tgid_stat),
2810 ONE("statm", S_IRUGO, proc_pid_statm),
2811 REG("maps", S_IRUGO, proc_maps_operations),
2812#ifdef CONFIG_NUMA
2813 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
2814#endif
2815 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2816 LNK("cwd", proc_cwd_link),
2817 LNK("root", proc_root_link),
2818 LNK("exe", proc_exe_link),
2819 REG("mounts", S_IRUGO, proc_mounts_operations),
2820 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2821 REG("mountstats", S_IRUSR, proc_mountstats_operations),
2822#ifdef CONFIG_PROC_PAGE_MONITOR
2823 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2824 REG("smaps", S_IRUGO, proc_smaps_operations),
2825 REG("pagemap", S_IRUGO, proc_pagemap_operations),
2826#endif
2827#ifdef CONFIG_SECURITY
2828 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
2829#endif
2830#ifdef CONFIG_KALLSYMS
2831 INF("wchan", S_IRUGO, proc_pid_wchan),
2832#endif
2833#ifdef CONFIG_STACKTRACE
2834 ONE("stack", S_IRUGO, proc_pid_stack),
2835#endif
2836#ifdef CONFIG_SCHEDSTATS
2837 INF("schedstat", S_IRUGO, proc_pid_schedstat),
2838#endif
2839#ifdef CONFIG_LATENCYTOP
2840 REG("latency", S_IRUGO, proc_lstats_operations),
2841#endif
2842#ifdef CONFIG_PROC_PID_CPUSET
2843 REG("cpuset", S_IRUGO, proc_cpuset_operations),
2844#endif
2845#ifdef CONFIG_CGROUPS
2846 REG("cgroup", S_IRUGO, proc_cgroup_operations),
2847#endif
2848 INF("oom_score", S_IRUGO, proc_oom_score),
2849 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
2850 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
2851#ifdef CONFIG_AUDITSYSCALL
2852 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2853 REG("sessionid", S_IRUGO, proc_sessionid_operations),
2854#endif
2855#ifdef CONFIG_FAULT_INJECTION
2856 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
2857#endif
2858#ifdef CONFIG_ELF_CORE
2859 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
2860#endif
2861#ifdef CONFIG_TASK_IO_ACCOUNTING
2862 INF("io", S_IRUSR, proc_tgid_io_accounting),
2863#endif
2864#ifdef CONFIG_HARDWALL
2865 INF("hardwall", S_IRUGO, proc_pid_hardwall),
2866#endif
2867};
2868
2869static int proc_tgid_base_readdir(struct file * filp,
2870 void * dirent, filldir_t filldir)
2871{
2872 return proc_pident_readdir(filp,dirent,filldir,
2873 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
2874}
2875
2876static const struct file_operations proc_tgid_base_operations = {
2877 .read = generic_read_dir,
2878 .readdir = proc_tgid_base_readdir,
2879 .llseek = default_llseek,
2880};
2881
2882static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
2883 return proc_pident_lookup(dir, dentry,
2884 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
2885}
2886
2887static const struct inode_operations proc_tgid_base_inode_operations = {
2888 .lookup = proc_tgid_base_lookup,
2889 .getattr = pid_getattr,
2890 .setattr = proc_setattr,
2891};
2892
2893static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
2894{
2895 struct dentry *dentry, *leader, *dir;
2896 char buf[PROC_NUMBUF];
2897 struct qstr name;
2898
2899 name.name = buf;
2900 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2901 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
2902 if (dentry) {
2903 shrink_dcache_parent(dentry);
2904 d_drop(dentry);
2905 dput(dentry);
2906 }
2907
2908 name.name = buf;
2909 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2910 leader = d_hash_and_lookup(mnt->mnt_root, &name);
2911 if (!leader)
2912 goto out;
2913
2914 name.name = "task";
2915 name.len = strlen(name.name);
2916 dir = d_hash_and_lookup(leader, &name);
2917 if (!dir)
2918 goto out_put_leader;
2919
2920 name.name = buf;
2921 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2922 dentry = d_hash_and_lookup(dir, &name);
2923 if (dentry) {
2924 shrink_dcache_parent(dentry);
2925 d_drop(dentry);
2926 dput(dentry);
2927 }
2928
2929 dput(dir);
2930out_put_leader:
2931 dput(leader);
2932out:
2933 return;
2934}
2935
2936/**
2937 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2938 * @task: task that should be flushed.
2939 *
2940 * When flushing dentries from proc, one needs to flush them from global
2941 * proc (proc_mnt) and from all the namespaces' procs this task was seen
2942 * in. This call is supposed to do all of this job.
2943 *
2944 * Looks in the dcache for
2945 * /proc/@pid
2946 * /proc/@tgid/task/@pid
2947 * if either directory is present flushes it and all of it'ts children
2948 * from the dcache.
2949 *
2950 * It is safe and reasonable to cache /proc entries for a task until
2951 * that task exits. After that they just clog up the dcache with
2952 * useless entries, possibly causing useful dcache entries to be
2953 * flushed instead. This routine is proved to flush those useless
2954 * dcache entries at process exit time.
2955 *
2956 * NOTE: This routine is just an optimization so it does not guarantee
2957 * that no dcache entries will exist at process exit time it
2958 * just makes it very unlikely that any will persist.
2959 */
2960
2961void proc_flush_task(struct task_struct *task)
2962{
2963 int i;
2964 struct pid *pid, *tgid;
2965 struct upid *upid;
2966
2967 pid = task_pid(task);
2968 tgid = task_tgid(task);
2969
2970 for (i = 0; i <= pid->level; i++) {
2971 upid = &pid->numbers[i];
2972 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
2973 tgid->numbers[i].nr);
2974 }
2975
2976 upid = &pid->numbers[pid->level];
2977 if (upid->nr == 1)
2978 pid_ns_release_proc(upid->ns);
2979}
2980
2981static struct dentry *proc_pid_instantiate(struct inode *dir,
2982 struct dentry * dentry,
2983 struct task_struct *task, const void *ptr)
2984{
2985 struct dentry *error = ERR_PTR(-ENOENT);
2986 struct inode *inode;
2987
2988 inode = proc_pid_make_inode(dir->i_sb, task);
2989 if (!inode)
2990 goto out;
2991
2992 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2993 inode->i_op = &proc_tgid_base_inode_operations;
2994 inode->i_fop = &proc_tgid_base_operations;
2995 inode->i_flags|=S_IMMUTABLE;
2996
2997 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
2998 ARRAY_SIZE(tgid_base_stuff));
2999
3000 d_set_d_op(dentry, &pid_dentry_operations);
3001
3002 d_add(dentry, inode);
3003 /* Close the race of the process dying before we return the dentry */
3004 if (pid_revalidate(dentry, NULL))
3005 error = NULL;
3006out:
3007 return error;
3008}
3009
3010struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3011{
3012 struct dentry *result;
3013 struct task_struct *task;
3014 unsigned tgid;
3015 struct pid_namespace *ns;
3016
3017 result = proc_base_lookup(dir, dentry);
3018 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
3019 goto out;
3020
3021 tgid = name_to_int(dentry);
3022 if (tgid == ~0U)
3023 goto out;
3024
3025 ns = dentry->d_sb->s_fs_info;
3026 rcu_read_lock();
3027 task = find_task_by_pid_ns(tgid, ns);
3028 if (task)
3029 get_task_struct(task);
3030 rcu_read_unlock();
3031 if (!task)
3032 goto out;
3033
3034 result = proc_pid_instantiate(dir, dentry, task, NULL);
3035 put_task_struct(task);
3036out:
3037 return result;
3038}
3039
3040/*
3041 * Find the first task with tgid >= tgid
3042 *
3043 */
3044struct tgid_iter {
3045 unsigned int tgid;
3046 struct task_struct *task;
3047};
3048static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3049{
3050 struct pid *pid;
3051
3052 if (iter.task)
3053 put_task_struct(iter.task);
3054 rcu_read_lock();
3055retry:
3056 iter.task = NULL;
3057 pid = find_ge_pid(iter.tgid, ns);
3058 if (pid) {
3059 iter.tgid = pid_nr_ns(pid, ns);
3060 iter.task = pid_task(pid, PIDTYPE_PID);
3061 /* What we to know is if the pid we have find is the
3062 * pid of a thread_group_leader. Testing for task
3063 * being a thread_group_leader is the obvious thing
3064 * todo but there is a window when it fails, due to
3065 * the pid transfer logic in de_thread.
3066 *
3067 * So we perform the straight forward test of seeing
3068 * if the pid we have found is the pid of a thread
3069 * group leader, and don't worry if the task we have
3070 * found doesn't happen to be a thread group leader.
3071 * As we don't care in the case of readdir.
3072 */
3073 if (!iter.task || !has_group_leader_pid(iter.task)) {
3074 iter.tgid += 1;
3075 goto retry;
3076 }
3077 get_task_struct(iter.task);
3078 }
3079 rcu_read_unlock();
3080 return iter;
3081}
3082
3083#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
3084
3085static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3086 struct tgid_iter iter)
3087{
3088 char name[PROC_NUMBUF];
3089 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
3090 return proc_fill_cache(filp, dirent, filldir, name, len,
3091 proc_pid_instantiate, iter.task, NULL);
3092}
3093
3094/* for the /proc/ directory itself, after non-process stuff has been done */
3095int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3096{
3097 unsigned int nr;
3098 struct task_struct *reaper;
3099 struct tgid_iter iter;
3100 struct pid_namespace *ns;
3101
3102 if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
3103 goto out_no_task;
3104 nr = filp->f_pos - FIRST_PROCESS_ENTRY;
3105
3106 reaper = get_proc_task(filp->f_path.dentry->d_inode);
3107 if (!reaper)
3108 goto out_no_task;
3109
3110 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
3111 const struct pid_entry *p = &proc_base_stuff[nr];
3112 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
3113 goto out;
3114 }
3115
3116 ns = filp->f_dentry->d_sb->s_fs_info;
3117 iter.task = NULL;
3118 iter.tgid = filp->f_pos - TGID_OFFSET;
3119 for (iter = next_tgid(ns, iter);
3120 iter.task;
3121 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3122 filp->f_pos = iter.tgid + TGID_OFFSET;
3123 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
3124 put_task_struct(iter.task);
3125 goto out;
3126 }
3127 }
3128 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3129out:
3130 put_task_struct(reaper);
3131out_no_task:
3132 return 0;
3133}
3134
3135/*
3136 * Tasks
3137 */
3138static const struct pid_entry tid_base_stuff[] = {
3139 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3140 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3141 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3142 REG("environ", S_IRUSR, proc_environ_operations),
3143 INF("auxv", S_IRUSR, proc_pid_auxv),
3144 ONE("status", S_IRUGO, proc_pid_status),
3145 ONE("personality", S_IRUGO, proc_pid_personality),
3146 INF("limits", S_IRUGO, proc_pid_limits),
3147#ifdef CONFIG_SCHED_DEBUG
3148 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3149#endif
3150 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3151#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3152 INF("syscall", S_IRUGO, proc_pid_syscall),
3153#endif
3154 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3155 ONE("stat", S_IRUGO, proc_tid_stat),
3156 ONE("statm", S_IRUGO, proc_pid_statm),
3157 REG("maps", S_IRUGO, proc_maps_operations),
3158#ifdef CONFIG_NUMA
3159 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
3160#endif
3161 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3162 LNK("cwd", proc_cwd_link),
3163 LNK("root", proc_root_link),
3164 LNK("exe", proc_exe_link),
3165 REG("mounts", S_IRUGO, proc_mounts_operations),
3166 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3167#ifdef CONFIG_PROC_PAGE_MONITOR
3168 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3169 REG("smaps", S_IRUGO, proc_smaps_operations),
3170 REG("pagemap", S_IRUGO, proc_pagemap_operations),
3171#endif
3172#ifdef CONFIG_SECURITY
3173 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3174#endif
3175#ifdef CONFIG_KALLSYMS
3176 INF("wchan", S_IRUGO, proc_pid_wchan),
3177#endif
3178#ifdef CONFIG_STACKTRACE
3179 ONE("stack", S_IRUGO, proc_pid_stack),
3180#endif
3181#ifdef CONFIG_SCHEDSTATS
3182 INF("schedstat", S_IRUGO, proc_pid_schedstat),
3183#endif
3184#ifdef CONFIG_LATENCYTOP
3185 REG("latency", S_IRUGO, proc_lstats_operations),
3186#endif
3187#ifdef CONFIG_PROC_PID_CPUSET
3188 REG("cpuset", S_IRUGO, proc_cpuset_operations),
3189#endif
3190#ifdef CONFIG_CGROUPS
3191 REG("cgroup", S_IRUGO, proc_cgroup_operations),
3192#endif
3193 INF("oom_score", S_IRUGO, proc_oom_score),
3194 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
3195 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3196#ifdef CONFIG_AUDITSYSCALL
3197 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3198 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3199#endif
3200#ifdef CONFIG_FAULT_INJECTION
3201 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3202#endif
3203#ifdef CONFIG_TASK_IO_ACCOUNTING
3204 INF("io", S_IRUSR, proc_tid_io_accounting),
3205#endif
3206#ifdef CONFIG_HARDWALL
3207 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3208#endif
3209};
3210
3211static int proc_tid_base_readdir(struct file * filp,
3212 void * dirent, filldir_t filldir)
3213{
3214 return proc_pident_readdir(filp,dirent,filldir,
3215 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3216}
3217
3218static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
3219 return proc_pident_lookup(dir, dentry,
3220 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3221}
3222
3223static const struct file_operations proc_tid_base_operations = {
3224 .read = generic_read_dir,
3225 .readdir = proc_tid_base_readdir,
3226 .llseek = default_llseek,
3227};
3228
3229static const struct inode_operations proc_tid_base_inode_operations = {
3230 .lookup = proc_tid_base_lookup,
3231 .getattr = pid_getattr,
3232 .setattr = proc_setattr,
3233};
3234
3235static struct dentry *proc_task_instantiate(struct inode *dir,
3236 struct dentry *dentry, struct task_struct *task, const void *ptr)
3237{
3238 struct dentry *error = ERR_PTR(-ENOENT);
3239 struct inode *inode;
3240 inode = proc_pid_make_inode(dir->i_sb, task);
3241
3242 if (!inode)
3243 goto out;
3244 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3245 inode->i_op = &proc_tid_base_inode_operations;
3246 inode->i_fop = &proc_tid_base_operations;
3247 inode->i_flags|=S_IMMUTABLE;
3248
3249 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
3250 ARRAY_SIZE(tid_base_stuff));
3251
3252 d_set_d_op(dentry, &pid_dentry_operations);
3253
3254 d_add(dentry, inode);
3255 /* Close the race of the process dying before we return the dentry */
3256 if (pid_revalidate(dentry, NULL))
3257 error = NULL;
3258out:
3259 return error;
3260}
3261
3262static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3263{
3264 struct dentry *result = ERR_PTR(-ENOENT);
3265 struct task_struct *task;
3266 struct task_struct *leader = get_proc_task(dir);
3267 unsigned tid;
3268 struct pid_namespace *ns;
3269
3270 if (!leader)
3271 goto out_no_task;
3272
3273 tid = name_to_int(dentry);
3274 if (tid == ~0U)
3275 goto out;
3276
3277 ns = dentry->d_sb->s_fs_info;
3278 rcu_read_lock();
3279 task = find_task_by_pid_ns(tid, ns);
3280 if (task)
3281 get_task_struct(task);
3282 rcu_read_unlock();
3283 if (!task)
3284 goto out;
3285 if (!same_thread_group(leader, task))
3286 goto out_drop_task;
3287
3288 result = proc_task_instantiate(dir, dentry, task, NULL);
3289out_drop_task:
3290 put_task_struct(task);
3291out:
3292 put_task_struct(leader);
3293out_no_task:
3294 return result;
3295}
3296
3297/*
3298 * Find the first tid of a thread group to return to user space.
3299 *
3300 * Usually this is just the thread group leader, but if the users
3301 * buffer was too small or there was a seek into the middle of the
3302 * directory we have more work todo.
3303 *
3304 * In the case of a short read we start with find_task_by_pid.
3305 *
3306 * In the case of a seek we start with the leader and walk nr
3307 * threads past it.
3308 */
3309static struct task_struct *first_tid(struct task_struct *leader,
3310 int tid, int nr, struct pid_namespace *ns)
3311{
3312 struct task_struct *pos;
3313
3314 rcu_read_lock();
3315 /* Attempt to start with the pid of a thread */
3316 if (tid && (nr > 0)) {
3317 pos = find_task_by_pid_ns(tid, ns);
3318 if (pos && (pos->group_leader == leader))
3319 goto found;
3320 }
3321
3322 /* If nr exceeds the number of threads there is nothing todo */
3323 pos = NULL;
3324 if (nr && nr >= get_nr_threads(leader))
3325 goto out;
3326
3327 /* If we haven't found our starting place yet start
3328 * with the leader and walk nr threads forward.
3329 */
3330 for (pos = leader; nr > 0; --nr) {
3331 pos = next_thread(pos);
3332 if (pos == leader) {
3333 pos = NULL;
3334 goto out;
3335 }
3336 }
3337found:
3338 get_task_struct(pos);
3339out:
3340 rcu_read_unlock();
3341 return pos;
3342}
3343
3344/*
3345 * Find the next thread in the thread list.
3346 * Return NULL if there is an error or no next thread.
3347 *
3348 * The reference to the input task_struct is released.
3349 */
3350static struct task_struct *next_tid(struct task_struct *start)
3351{
3352 struct task_struct *pos = NULL;
3353 rcu_read_lock();
3354 if (pid_alive(start)) {
3355 pos = next_thread(start);
3356 if (thread_group_leader(pos))
3357 pos = NULL;
3358 else
3359 get_task_struct(pos);
3360 }
3361 rcu_read_unlock();
3362 put_task_struct(start);
3363 return pos;
3364}
3365
3366static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3367 struct task_struct *task, int tid)
3368{
3369 char name[PROC_NUMBUF];
3370 int len = snprintf(name, sizeof(name), "%d", tid);
3371 return proc_fill_cache(filp, dirent, filldir, name, len,
3372 proc_task_instantiate, task, NULL);
3373}
3374
3375/* for the /proc/TGID/task/ directories */
3376static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3377{
3378 struct dentry *dentry = filp->f_path.dentry;
3379 struct inode *inode = dentry->d_inode;
3380 struct task_struct *leader = NULL;
3381 struct task_struct *task;
3382 int retval = -ENOENT;
3383 ino_t ino;
3384 int tid;
3385 struct pid_namespace *ns;
3386
3387 task = get_proc_task(inode);
3388 if (!task)
3389 goto out_no_task;
3390 rcu_read_lock();
3391 if (pid_alive(task)) {
3392 leader = task->group_leader;
3393 get_task_struct(leader);
3394 }
3395 rcu_read_unlock();
3396 put_task_struct(task);
3397 if (!leader)
3398 goto out_no_task;
3399 retval = 0;
3400
3401 switch ((unsigned long)filp->f_pos) {
3402 case 0:
3403 ino = inode->i_ino;
3404 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
3405 goto out;
3406 filp->f_pos++;
3407 /* fall through */
3408 case 1:
3409 ino = parent_ino(dentry);
3410 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
3411 goto out;
3412 filp->f_pos++;
3413 /* fall through */
3414 }
3415
3416 /* f_version caches the tgid value that the last readdir call couldn't
3417 * return. lseek aka telldir automagically resets f_version to 0.
3418 */
3419 ns = filp->f_dentry->d_sb->s_fs_info;
3420 tid = (int)filp->f_version;
3421 filp->f_version = 0;
3422 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
3423 task;
3424 task = next_tid(task), filp->f_pos++) {
3425 tid = task_pid_nr_ns(task, ns);
3426 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
3427 /* returning this tgid failed, save it as the first
3428 * pid for the next readir call */
3429 filp->f_version = (u64)tid;
3430 put_task_struct(task);
3431 break;
3432 }
3433 }
3434out:
3435 put_task_struct(leader);
3436out_no_task:
3437 return retval;
3438}
3439
3440static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3441{
3442 struct inode *inode = dentry->d_inode;
3443 struct task_struct *p = get_proc_task(inode);
3444 generic_fillattr(inode, stat);
3445
3446 if (p) {
3447 stat->nlink += get_nr_threads(p);
3448 put_task_struct(p);
3449 }
3450
3451 return 0;
3452}
3453
3454static const struct inode_operations proc_task_inode_operations = {
3455 .lookup = proc_task_lookup,
3456 .getattr = proc_task_getattr,
3457 .setattr = proc_setattr,
3458};
3459
3460static const struct file_operations proc_task_operations = {
3461 .read = generic_read_dir,
3462 .readdir = proc_task_readdir,
3463 .llseek = default_llseek,
3464};
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/printk.h>
77#include <linux/cgroup.h>
78#include <linux/cpuset.h>
79#include <linux/audit.h>
80#include <linux/poll.h>
81#include <linux/nsproxy.h>
82#include <linux/oom.h>
83#include <linux/elf.h>
84#include <linux/pid_namespace.h>
85#include <linux/user_namespace.h>
86#include <linux/fs_struct.h>
87#include <linux/slab.h>
88#include <linux/flex_array.h>
89#include <linux/posix-timers.h>
90#ifdef CONFIG_HARDWALL
91#include <asm/hardwall.h>
92#endif
93#include <trace/events/oom.h>
94#include "internal.h"
95#include "fd.h"
96
97/* NOTE:
98 * Implementing inode permission operations in /proc is almost
99 * certainly an error. Permission checks need to happen during
100 * each system call not at open time. The reason is that most of
101 * what we wish to check for permissions in /proc varies at runtime.
102 *
103 * The classic example of a problem is opening file descriptors
104 * in /proc for a task before it execs a suid executable.
105 */
106
107struct pid_entry {
108 const char *name;
109 int len;
110 umode_t mode;
111 const struct inode_operations *iop;
112 const struct file_operations *fop;
113 union proc_op op;
114};
115
116#define NOD(NAME, MODE, IOP, FOP, OP) { \
117 .name = (NAME), \
118 .len = sizeof(NAME) - 1, \
119 .mode = MODE, \
120 .iop = IOP, \
121 .fop = FOP, \
122 .op = OP, \
123}
124
125#define DIR(NAME, MODE, iops, fops) \
126 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
127#define LNK(NAME, get_link) \
128 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
129 &proc_pid_link_inode_operations, NULL, \
130 { .proc_get_link = get_link } )
131#define REG(NAME, MODE, fops) \
132 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
133#define ONE(NAME, MODE, show) \
134 NOD(NAME, (S_IFREG|(MODE)), \
135 NULL, &proc_single_file_operations, \
136 { .proc_show = show } )
137
138/*
139 * Count the number of hardlinks for the pid_entry table, excluding the .
140 * and .. links.
141 */
142static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
143 unsigned int n)
144{
145 unsigned int i;
146 unsigned int count;
147
148 count = 0;
149 for (i = 0; i < n; ++i) {
150 if (S_ISDIR(entries[i].mode))
151 ++count;
152 }
153
154 return count;
155}
156
157static int get_task_root(struct task_struct *task, struct path *root)
158{
159 int result = -ENOENT;
160
161 task_lock(task);
162 if (task->fs) {
163 get_fs_root(task->fs, root);
164 result = 0;
165 }
166 task_unlock(task);
167 return result;
168}
169
170static int proc_cwd_link(struct dentry *dentry, struct path *path)
171{
172 struct task_struct *task = get_proc_task(d_inode(dentry));
173 int result = -ENOENT;
174
175 if (task) {
176 task_lock(task);
177 if (task->fs) {
178 get_fs_pwd(task->fs, path);
179 result = 0;
180 }
181 task_unlock(task);
182 put_task_struct(task);
183 }
184 return result;
185}
186
187static int proc_root_link(struct dentry *dentry, struct path *path)
188{
189 struct task_struct *task = get_proc_task(d_inode(dentry));
190 int result = -ENOENT;
191
192 if (task) {
193 result = get_task_root(task, path);
194 put_task_struct(task);
195 }
196 return result;
197}
198
199static ssize_t proc_pid_cmdline_read(struct file *file, char __user *buf,
200 size_t _count, loff_t *pos)
201{
202 struct task_struct *tsk;
203 struct mm_struct *mm;
204 char *page;
205 unsigned long count = _count;
206 unsigned long arg_start, arg_end, env_start, env_end;
207 unsigned long len1, len2, len;
208 unsigned long p;
209 char c;
210 ssize_t rv;
211
212 BUG_ON(*pos < 0);
213
214 tsk = get_proc_task(file_inode(file));
215 if (!tsk)
216 return -ESRCH;
217 mm = get_task_mm(tsk);
218 put_task_struct(tsk);
219 if (!mm)
220 return 0;
221 /* Check if process spawned far enough to have cmdline. */
222 if (!mm->env_end) {
223 rv = 0;
224 goto out_mmput;
225 }
226
227 page = (char *)__get_free_page(GFP_TEMPORARY);
228 if (!page) {
229 rv = -ENOMEM;
230 goto out_mmput;
231 }
232
233 down_read(&mm->mmap_sem);
234 arg_start = mm->arg_start;
235 arg_end = mm->arg_end;
236 env_start = mm->env_start;
237 env_end = mm->env_end;
238 up_read(&mm->mmap_sem);
239
240 BUG_ON(arg_start > arg_end);
241 BUG_ON(env_start > env_end);
242
243 len1 = arg_end - arg_start;
244 len2 = env_end - env_start;
245
246 /* Empty ARGV. */
247 if (len1 == 0) {
248 rv = 0;
249 goto out_free_page;
250 }
251 /*
252 * Inherently racy -- command line shares address space
253 * with code and data.
254 */
255 rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0);
256 if (rv <= 0)
257 goto out_free_page;
258
259 rv = 0;
260
261 if (c == '\0') {
262 /* Command line (set of strings) occupies whole ARGV. */
263 if (len1 <= *pos)
264 goto out_free_page;
265
266 p = arg_start + *pos;
267 len = len1 - *pos;
268 while (count > 0 && len > 0) {
269 unsigned int _count;
270 int nr_read;
271
272 _count = min3(count, len, PAGE_SIZE);
273 nr_read = access_remote_vm(mm, p, page, _count, 0);
274 if (nr_read < 0)
275 rv = nr_read;
276 if (nr_read <= 0)
277 goto out_free_page;
278
279 if (copy_to_user(buf, page, nr_read)) {
280 rv = -EFAULT;
281 goto out_free_page;
282 }
283
284 p += nr_read;
285 len -= nr_read;
286 buf += nr_read;
287 count -= nr_read;
288 rv += nr_read;
289 }
290 } else {
291 /*
292 * Command line (1 string) occupies ARGV and maybe
293 * extends into ENVP.
294 */
295 if (len1 + len2 <= *pos)
296 goto skip_argv_envp;
297 if (len1 <= *pos)
298 goto skip_argv;
299
300 p = arg_start + *pos;
301 len = len1 - *pos;
302 while (count > 0 && len > 0) {
303 unsigned int _count, l;
304 int nr_read;
305 bool final;
306
307 _count = min3(count, len, PAGE_SIZE);
308 nr_read = access_remote_vm(mm, p, page, _count, 0);
309 if (nr_read < 0)
310 rv = nr_read;
311 if (nr_read <= 0)
312 goto out_free_page;
313
314 /*
315 * Command line can be shorter than whole ARGV
316 * even if last "marker" byte says it is not.
317 */
318 final = false;
319 l = strnlen(page, nr_read);
320 if (l < nr_read) {
321 nr_read = l;
322 final = true;
323 }
324
325 if (copy_to_user(buf, page, nr_read)) {
326 rv = -EFAULT;
327 goto out_free_page;
328 }
329
330 p += nr_read;
331 len -= nr_read;
332 buf += nr_read;
333 count -= nr_read;
334 rv += nr_read;
335
336 if (final)
337 goto out_free_page;
338 }
339skip_argv:
340 /*
341 * Command line (1 string) occupies ARGV and
342 * extends into ENVP.
343 */
344 if (len1 <= *pos) {
345 p = env_start + *pos - len1;
346 len = len1 + len2 - *pos;
347 } else {
348 p = env_start;
349 len = len2;
350 }
351 while (count > 0 && len > 0) {
352 unsigned int _count, l;
353 int nr_read;
354 bool final;
355
356 _count = min3(count, len, PAGE_SIZE);
357 nr_read = access_remote_vm(mm, p, page, _count, 0);
358 if (nr_read < 0)
359 rv = nr_read;
360 if (nr_read <= 0)
361 goto out_free_page;
362
363 /* Find EOS. */
364 final = false;
365 l = strnlen(page, nr_read);
366 if (l < nr_read) {
367 nr_read = l;
368 final = true;
369 }
370
371 if (copy_to_user(buf, page, nr_read)) {
372 rv = -EFAULT;
373 goto out_free_page;
374 }
375
376 p += nr_read;
377 len -= nr_read;
378 buf += nr_read;
379 count -= nr_read;
380 rv += nr_read;
381
382 if (final)
383 goto out_free_page;
384 }
385skip_argv_envp:
386 ;
387 }
388
389out_free_page:
390 free_page((unsigned long)page);
391out_mmput:
392 mmput(mm);
393 if (rv > 0)
394 *pos += rv;
395 return rv;
396}
397
398static const struct file_operations proc_pid_cmdline_ops = {
399 .read = proc_pid_cmdline_read,
400 .llseek = generic_file_llseek,
401};
402
403static int proc_pid_auxv(struct seq_file *m, struct pid_namespace *ns,
404 struct pid *pid, struct task_struct *task)
405{
406 struct mm_struct *mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
407 if (mm && !IS_ERR(mm)) {
408 unsigned int nwords = 0;
409 do {
410 nwords += 2;
411 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
412 seq_write(m, mm->saved_auxv, nwords * sizeof(mm->saved_auxv[0]));
413 mmput(mm);
414 return 0;
415 } else
416 return PTR_ERR(mm);
417}
418
419
420#ifdef CONFIG_KALLSYMS
421/*
422 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
423 * Returns the resolved symbol. If that fails, simply return the address.
424 */
425static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
426 struct pid *pid, struct task_struct *task)
427{
428 unsigned long wchan;
429 char symname[KSYM_NAME_LEN];
430
431 wchan = get_wchan(task);
432
433 if (wchan && ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)
434 && !lookup_symbol_name(wchan, symname))
435 seq_printf(m, "%s", symname);
436 else
437 seq_putc(m, '0');
438
439 return 0;
440}
441#endif /* CONFIG_KALLSYMS */
442
443static int lock_trace(struct task_struct *task)
444{
445 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
446 if (err)
447 return err;
448 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
449 mutex_unlock(&task->signal->cred_guard_mutex);
450 return -EPERM;
451 }
452 return 0;
453}
454
455static void unlock_trace(struct task_struct *task)
456{
457 mutex_unlock(&task->signal->cred_guard_mutex);
458}
459
460#ifdef CONFIG_STACKTRACE
461
462#define MAX_STACK_TRACE_DEPTH 64
463
464static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
465 struct pid *pid, struct task_struct *task)
466{
467 struct stack_trace trace;
468 unsigned long *entries;
469 int err;
470 int i;
471
472 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
473 if (!entries)
474 return -ENOMEM;
475
476 trace.nr_entries = 0;
477 trace.max_entries = MAX_STACK_TRACE_DEPTH;
478 trace.entries = entries;
479 trace.skip = 0;
480
481 err = lock_trace(task);
482 if (!err) {
483 save_stack_trace_tsk(task, &trace);
484
485 for (i = 0; i < trace.nr_entries; i++) {
486 seq_printf(m, "[<%pK>] %pS\n",
487 (void *)entries[i], (void *)entries[i]);
488 }
489 unlock_trace(task);
490 }
491 kfree(entries);
492
493 return err;
494}
495#endif
496
497#ifdef CONFIG_SCHED_INFO
498/*
499 * Provides /proc/PID/schedstat
500 */
501static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
502 struct pid *pid, struct task_struct *task)
503{
504 if (unlikely(!sched_info_on()))
505 seq_printf(m, "0 0 0\n");
506 else
507 seq_printf(m, "%llu %llu %lu\n",
508 (unsigned long long)task->se.sum_exec_runtime,
509 (unsigned long long)task->sched_info.run_delay,
510 task->sched_info.pcount);
511
512 return 0;
513}
514#endif
515
516#ifdef CONFIG_LATENCYTOP
517static int lstats_show_proc(struct seq_file *m, void *v)
518{
519 int i;
520 struct inode *inode = m->private;
521 struct task_struct *task = get_proc_task(inode);
522
523 if (!task)
524 return -ESRCH;
525 seq_puts(m, "Latency Top version : v0.1\n");
526 for (i = 0; i < 32; i++) {
527 struct latency_record *lr = &task->latency_record[i];
528 if (lr->backtrace[0]) {
529 int q;
530 seq_printf(m, "%i %li %li",
531 lr->count, lr->time, lr->max);
532 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
533 unsigned long bt = lr->backtrace[q];
534 if (!bt)
535 break;
536 if (bt == ULONG_MAX)
537 break;
538 seq_printf(m, " %ps", (void *)bt);
539 }
540 seq_putc(m, '\n');
541 }
542
543 }
544 put_task_struct(task);
545 return 0;
546}
547
548static int lstats_open(struct inode *inode, struct file *file)
549{
550 return single_open(file, lstats_show_proc, inode);
551}
552
553static ssize_t lstats_write(struct file *file, const char __user *buf,
554 size_t count, loff_t *offs)
555{
556 struct task_struct *task = get_proc_task(file_inode(file));
557
558 if (!task)
559 return -ESRCH;
560 clear_all_latency_tracing(task);
561 put_task_struct(task);
562
563 return count;
564}
565
566static const struct file_operations proc_lstats_operations = {
567 .open = lstats_open,
568 .read = seq_read,
569 .write = lstats_write,
570 .llseek = seq_lseek,
571 .release = single_release,
572};
573
574#endif
575
576static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
577 struct pid *pid, struct task_struct *task)
578{
579 unsigned long totalpages = totalram_pages + total_swap_pages;
580 unsigned long points = 0;
581
582 read_lock(&tasklist_lock);
583 if (pid_alive(task))
584 points = oom_badness(task, NULL, NULL, totalpages) *
585 1000 / totalpages;
586 read_unlock(&tasklist_lock);
587 seq_printf(m, "%lu\n", points);
588
589 return 0;
590}
591
592struct limit_names {
593 const char *name;
594 const char *unit;
595};
596
597static const struct limit_names lnames[RLIM_NLIMITS] = {
598 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
599 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
600 [RLIMIT_DATA] = {"Max data size", "bytes"},
601 [RLIMIT_STACK] = {"Max stack size", "bytes"},
602 [RLIMIT_CORE] = {"Max core file size", "bytes"},
603 [RLIMIT_RSS] = {"Max resident set", "bytes"},
604 [RLIMIT_NPROC] = {"Max processes", "processes"},
605 [RLIMIT_NOFILE] = {"Max open files", "files"},
606 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
607 [RLIMIT_AS] = {"Max address space", "bytes"},
608 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
609 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
610 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
611 [RLIMIT_NICE] = {"Max nice priority", NULL},
612 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
613 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
614};
615
616/* Display limits for a process */
617static int proc_pid_limits(struct seq_file *m, struct pid_namespace *ns,
618 struct pid *pid, struct task_struct *task)
619{
620 unsigned int i;
621 unsigned long flags;
622
623 struct rlimit rlim[RLIM_NLIMITS];
624
625 if (!lock_task_sighand(task, &flags))
626 return 0;
627 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
628 unlock_task_sighand(task, &flags);
629
630 /*
631 * print the file header
632 */
633 seq_printf(m, "%-25s %-20s %-20s %-10s\n",
634 "Limit", "Soft Limit", "Hard Limit", "Units");
635
636 for (i = 0; i < RLIM_NLIMITS; i++) {
637 if (rlim[i].rlim_cur == RLIM_INFINITY)
638 seq_printf(m, "%-25s %-20s ",
639 lnames[i].name, "unlimited");
640 else
641 seq_printf(m, "%-25s %-20lu ",
642 lnames[i].name, rlim[i].rlim_cur);
643
644 if (rlim[i].rlim_max == RLIM_INFINITY)
645 seq_printf(m, "%-20s ", "unlimited");
646 else
647 seq_printf(m, "%-20lu ", rlim[i].rlim_max);
648
649 if (lnames[i].unit)
650 seq_printf(m, "%-10s\n", lnames[i].unit);
651 else
652 seq_putc(m, '\n');
653 }
654
655 return 0;
656}
657
658#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
659static int proc_pid_syscall(struct seq_file *m, struct pid_namespace *ns,
660 struct pid *pid, struct task_struct *task)
661{
662 long nr;
663 unsigned long args[6], sp, pc;
664 int res;
665
666 res = lock_trace(task);
667 if (res)
668 return res;
669
670 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
671 seq_puts(m, "running\n");
672 else if (nr < 0)
673 seq_printf(m, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
674 else
675 seq_printf(m,
676 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
677 nr,
678 args[0], args[1], args[2], args[3], args[4], args[5],
679 sp, pc);
680 unlock_trace(task);
681
682 return 0;
683}
684#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
685
686/************************************************************************/
687/* Here the fs part begins */
688/************************************************************************/
689
690/* permission checks */
691static int proc_fd_access_allowed(struct inode *inode)
692{
693 struct task_struct *task;
694 int allowed = 0;
695 /* Allow access to a task's file descriptors if it is us or we
696 * may use ptrace attach to the process and find out that
697 * information.
698 */
699 task = get_proc_task(inode);
700 if (task) {
701 allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
702 put_task_struct(task);
703 }
704 return allowed;
705}
706
707int proc_setattr(struct dentry *dentry, struct iattr *attr)
708{
709 int error;
710 struct inode *inode = d_inode(dentry);
711
712 if (attr->ia_valid & ATTR_MODE)
713 return -EPERM;
714
715 error = inode_change_ok(inode, attr);
716 if (error)
717 return error;
718
719 setattr_copy(inode, attr);
720 mark_inode_dirty(inode);
721 return 0;
722}
723
724/*
725 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
726 * or euid/egid (for hide_pid_min=2)?
727 */
728static bool has_pid_permissions(struct pid_namespace *pid,
729 struct task_struct *task,
730 int hide_pid_min)
731{
732 if (pid->hide_pid < hide_pid_min)
733 return true;
734 if (in_group_p(pid->pid_gid))
735 return true;
736 return ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
737}
738
739
740static int proc_pid_permission(struct inode *inode, int mask)
741{
742 struct pid_namespace *pid = inode->i_sb->s_fs_info;
743 struct task_struct *task;
744 bool has_perms;
745
746 task = get_proc_task(inode);
747 if (!task)
748 return -ESRCH;
749 has_perms = has_pid_permissions(pid, task, 1);
750 put_task_struct(task);
751
752 if (!has_perms) {
753 if (pid->hide_pid == 2) {
754 /*
755 * Let's make getdents(), stat(), and open()
756 * consistent with each other. If a process
757 * may not stat() a file, it shouldn't be seen
758 * in procfs at all.
759 */
760 return -ENOENT;
761 }
762
763 return -EPERM;
764 }
765 return generic_permission(inode, mask);
766}
767
768
769
770static const struct inode_operations proc_def_inode_operations = {
771 .setattr = proc_setattr,
772};
773
774static int proc_single_show(struct seq_file *m, void *v)
775{
776 struct inode *inode = m->private;
777 struct pid_namespace *ns;
778 struct pid *pid;
779 struct task_struct *task;
780 int ret;
781
782 ns = inode->i_sb->s_fs_info;
783 pid = proc_pid(inode);
784 task = get_pid_task(pid, PIDTYPE_PID);
785 if (!task)
786 return -ESRCH;
787
788 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
789
790 put_task_struct(task);
791 return ret;
792}
793
794static int proc_single_open(struct inode *inode, struct file *filp)
795{
796 return single_open(filp, proc_single_show, inode);
797}
798
799static const struct file_operations proc_single_file_operations = {
800 .open = proc_single_open,
801 .read = seq_read,
802 .llseek = seq_lseek,
803 .release = single_release,
804};
805
806
807struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)
808{
809 struct task_struct *task = get_proc_task(inode);
810 struct mm_struct *mm = ERR_PTR(-ESRCH);
811
812 if (task) {
813 mm = mm_access(task, mode | PTRACE_MODE_FSCREDS);
814 put_task_struct(task);
815
816 if (!IS_ERR_OR_NULL(mm)) {
817 /* ensure this mm_struct can't be freed */
818 atomic_inc(&mm->mm_count);
819 /* but do not pin its memory */
820 mmput(mm);
821 }
822 }
823
824 return mm;
825}
826
827static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)
828{
829 struct mm_struct *mm = proc_mem_open(inode, mode);
830
831 if (IS_ERR(mm))
832 return PTR_ERR(mm);
833
834 file->private_data = mm;
835 return 0;
836}
837
838static int mem_open(struct inode *inode, struct file *file)
839{
840 int ret = __mem_open(inode, file, PTRACE_MODE_ATTACH);
841
842 /* OK to pass negative loff_t, we can catch out-of-range */
843 file->f_mode |= FMODE_UNSIGNED_OFFSET;
844
845 return ret;
846}
847
848static ssize_t mem_rw(struct file *file, char __user *buf,
849 size_t count, loff_t *ppos, int write)
850{
851 struct mm_struct *mm = file->private_data;
852 unsigned long addr = *ppos;
853 ssize_t copied;
854 char *page;
855
856 if (!mm)
857 return 0;
858
859 page = (char *)__get_free_page(GFP_TEMPORARY);
860 if (!page)
861 return -ENOMEM;
862
863 copied = 0;
864 if (!atomic_inc_not_zero(&mm->mm_users))
865 goto free;
866
867 while (count > 0) {
868 int this_len = min_t(int, count, PAGE_SIZE);
869
870 if (write && copy_from_user(page, buf, this_len)) {
871 copied = -EFAULT;
872 break;
873 }
874
875 this_len = access_remote_vm(mm, addr, page, this_len, write);
876 if (!this_len) {
877 if (!copied)
878 copied = -EIO;
879 break;
880 }
881
882 if (!write && copy_to_user(buf, page, this_len)) {
883 copied = -EFAULT;
884 break;
885 }
886
887 buf += this_len;
888 addr += this_len;
889 copied += this_len;
890 count -= this_len;
891 }
892 *ppos = addr;
893
894 mmput(mm);
895free:
896 free_page((unsigned long) page);
897 return copied;
898}
899
900static ssize_t mem_read(struct file *file, char __user *buf,
901 size_t count, loff_t *ppos)
902{
903 return mem_rw(file, buf, count, ppos, 0);
904}
905
906static ssize_t mem_write(struct file *file, const char __user *buf,
907 size_t count, loff_t *ppos)
908{
909 return mem_rw(file, (char __user*)buf, count, ppos, 1);
910}
911
912loff_t mem_lseek(struct file *file, loff_t offset, int orig)
913{
914 switch (orig) {
915 case 0:
916 file->f_pos = offset;
917 break;
918 case 1:
919 file->f_pos += offset;
920 break;
921 default:
922 return -EINVAL;
923 }
924 force_successful_syscall_return();
925 return file->f_pos;
926}
927
928static int mem_release(struct inode *inode, struct file *file)
929{
930 struct mm_struct *mm = file->private_data;
931 if (mm)
932 mmdrop(mm);
933 return 0;
934}
935
936static const struct file_operations proc_mem_operations = {
937 .llseek = mem_lseek,
938 .read = mem_read,
939 .write = mem_write,
940 .open = mem_open,
941 .release = mem_release,
942};
943
944static int environ_open(struct inode *inode, struct file *file)
945{
946 return __mem_open(inode, file, PTRACE_MODE_READ);
947}
948
949static ssize_t environ_read(struct file *file, char __user *buf,
950 size_t count, loff_t *ppos)
951{
952 char *page;
953 unsigned long src = *ppos;
954 int ret = 0;
955 struct mm_struct *mm = file->private_data;
956 unsigned long env_start, env_end;
957
958 /* Ensure the process spawned far enough to have an environment. */
959 if (!mm || !mm->env_end)
960 return 0;
961
962 page = (char *)__get_free_page(GFP_TEMPORARY);
963 if (!page)
964 return -ENOMEM;
965
966 ret = 0;
967 if (!atomic_inc_not_zero(&mm->mm_users))
968 goto free;
969
970 down_read(&mm->mmap_sem);
971 env_start = mm->env_start;
972 env_end = mm->env_end;
973 up_read(&mm->mmap_sem);
974
975 while (count > 0) {
976 size_t this_len, max_len;
977 int retval;
978
979 if (src >= (env_end - env_start))
980 break;
981
982 this_len = env_end - (env_start + src);
983
984 max_len = min_t(size_t, PAGE_SIZE, count);
985 this_len = min(max_len, this_len);
986
987 retval = access_remote_vm(mm, (env_start + src),
988 page, this_len, 0);
989
990 if (retval <= 0) {
991 ret = retval;
992 break;
993 }
994
995 if (copy_to_user(buf, page, retval)) {
996 ret = -EFAULT;
997 break;
998 }
999
1000 ret += retval;
1001 src += retval;
1002 buf += retval;
1003 count -= retval;
1004 }
1005 *ppos = src;
1006 mmput(mm);
1007
1008free:
1009 free_page((unsigned long) page);
1010 return ret;
1011}
1012
1013static const struct file_operations proc_environ_operations = {
1014 .open = environ_open,
1015 .read = environ_read,
1016 .llseek = generic_file_llseek,
1017 .release = mem_release,
1018};
1019
1020static ssize_t oom_adj_read(struct file *file, char __user *buf, size_t count,
1021 loff_t *ppos)
1022{
1023 struct task_struct *task = get_proc_task(file_inode(file));
1024 char buffer[PROC_NUMBUF];
1025 int oom_adj = OOM_ADJUST_MIN;
1026 size_t len;
1027 unsigned long flags;
1028
1029 if (!task)
1030 return -ESRCH;
1031 if (lock_task_sighand(task, &flags)) {
1032 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MAX)
1033 oom_adj = OOM_ADJUST_MAX;
1034 else
1035 oom_adj = (task->signal->oom_score_adj * -OOM_DISABLE) /
1036 OOM_SCORE_ADJ_MAX;
1037 unlock_task_sighand(task, &flags);
1038 }
1039 put_task_struct(task);
1040 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_adj);
1041 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1042}
1043
1044/*
1045 * /proc/pid/oom_adj exists solely for backwards compatibility with previous
1046 * kernels. The effective policy is defined by oom_score_adj, which has a
1047 * different scale: oom_adj grew exponentially and oom_score_adj grows linearly.
1048 * Values written to oom_adj are simply mapped linearly to oom_score_adj.
1049 * Processes that become oom disabled via oom_adj will still be oom disabled
1050 * with this implementation.
1051 *
1052 * oom_adj cannot be removed since existing userspace binaries use it.
1053 */
1054static ssize_t oom_adj_write(struct file *file, const char __user *buf,
1055 size_t count, loff_t *ppos)
1056{
1057 struct task_struct *task;
1058 char buffer[PROC_NUMBUF];
1059 int oom_adj;
1060 unsigned long flags;
1061 int err;
1062
1063 memset(buffer, 0, sizeof(buffer));
1064 if (count > sizeof(buffer) - 1)
1065 count = sizeof(buffer) - 1;
1066 if (copy_from_user(buffer, buf, count)) {
1067 err = -EFAULT;
1068 goto out;
1069 }
1070
1071 err = kstrtoint(strstrip(buffer), 0, &oom_adj);
1072 if (err)
1073 goto out;
1074 if ((oom_adj < OOM_ADJUST_MIN || oom_adj > OOM_ADJUST_MAX) &&
1075 oom_adj != OOM_DISABLE) {
1076 err = -EINVAL;
1077 goto out;
1078 }
1079
1080 task = get_proc_task(file_inode(file));
1081 if (!task) {
1082 err = -ESRCH;
1083 goto out;
1084 }
1085
1086 task_lock(task);
1087 if (!task->mm) {
1088 err = -EINVAL;
1089 goto err_task_lock;
1090 }
1091
1092 if (!lock_task_sighand(task, &flags)) {
1093 err = -ESRCH;
1094 goto err_task_lock;
1095 }
1096
1097 /*
1098 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1099 * value is always attainable.
1100 */
1101 if (oom_adj == OOM_ADJUST_MAX)
1102 oom_adj = OOM_SCORE_ADJ_MAX;
1103 else
1104 oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE;
1105
1106 if (oom_adj < task->signal->oom_score_adj &&
1107 !capable(CAP_SYS_RESOURCE)) {
1108 err = -EACCES;
1109 goto err_sighand;
1110 }
1111
1112 /*
1113 * /proc/pid/oom_adj is provided for legacy purposes, ask users to use
1114 * /proc/pid/oom_score_adj instead.
1115 */
1116 pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
1117 current->comm, task_pid_nr(current), task_pid_nr(task),
1118 task_pid_nr(task));
1119
1120 task->signal->oom_score_adj = oom_adj;
1121 trace_oom_score_adj_update(task);
1122err_sighand:
1123 unlock_task_sighand(task, &flags);
1124err_task_lock:
1125 task_unlock(task);
1126 put_task_struct(task);
1127out:
1128 return err < 0 ? err : count;
1129}
1130
1131static const struct file_operations proc_oom_adj_operations = {
1132 .read = oom_adj_read,
1133 .write = oom_adj_write,
1134 .llseek = generic_file_llseek,
1135};
1136
1137static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1138 size_t count, loff_t *ppos)
1139{
1140 struct task_struct *task = get_proc_task(file_inode(file));
1141 char buffer[PROC_NUMBUF];
1142 short oom_score_adj = OOM_SCORE_ADJ_MIN;
1143 unsigned long flags;
1144 size_t len;
1145
1146 if (!task)
1147 return -ESRCH;
1148 if (lock_task_sighand(task, &flags)) {
1149 oom_score_adj = task->signal->oom_score_adj;
1150 unlock_task_sighand(task, &flags);
1151 }
1152 put_task_struct(task);
1153 len = snprintf(buffer, sizeof(buffer), "%hd\n", oom_score_adj);
1154 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1155}
1156
1157static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1158 size_t count, loff_t *ppos)
1159{
1160 struct task_struct *task;
1161 char buffer[PROC_NUMBUF];
1162 unsigned long flags;
1163 int oom_score_adj;
1164 int err;
1165
1166 memset(buffer, 0, sizeof(buffer));
1167 if (count > sizeof(buffer) - 1)
1168 count = sizeof(buffer) - 1;
1169 if (copy_from_user(buffer, buf, count)) {
1170 err = -EFAULT;
1171 goto out;
1172 }
1173
1174 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1175 if (err)
1176 goto out;
1177 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1178 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1179 err = -EINVAL;
1180 goto out;
1181 }
1182
1183 task = get_proc_task(file_inode(file));
1184 if (!task) {
1185 err = -ESRCH;
1186 goto out;
1187 }
1188
1189 task_lock(task);
1190 if (!task->mm) {
1191 err = -EINVAL;
1192 goto err_task_lock;
1193 }
1194
1195 if (!lock_task_sighand(task, &flags)) {
1196 err = -ESRCH;
1197 goto err_task_lock;
1198 }
1199
1200 if ((short)oom_score_adj < task->signal->oom_score_adj_min &&
1201 !capable(CAP_SYS_RESOURCE)) {
1202 err = -EACCES;
1203 goto err_sighand;
1204 }
1205
1206 task->signal->oom_score_adj = (short)oom_score_adj;
1207 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1208 task->signal->oom_score_adj_min = (short)oom_score_adj;
1209 trace_oom_score_adj_update(task);
1210
1211err_sighand:
1212 unlock_task_sighand(task, &flags);
1213err_task_lock:
1214 task_unlock(task);
1215 put_task_struct(task);
1216out:
1217 return err < 0 ? err : count;
1218}
1219
1220static const struct file_operations proc_oom_score_adj_operations = {
1221 .read = oom_score_adj_read,
1222 .write = oom_score_adj_write,
1223 .llseek = default_llseek,
1224};
1225
1226#ifdef CONFIG_AUDITSYSCALL
1227#define TMPBUFLEN 21
1228static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1229 size_t count, loff_t *ppos)
1230{
1231 struct inode * inode = file_inode(file);
1232 struct task_struct *task = get_proc_task(inode);
1233 ssize_t length;
1234 char tmpbuf[TMPBUFLEN];
1235
1236 if (!task)
1237 return -ESRCH;
1238 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1239 from_kuid(file->f_cred->user_ns,
1240 audit_get_loginuid(task)));
1241 put_task_struct(task);
1242 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1243}
1244
1245static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1246 size_t count, loff_t *ppos)
1247{
1248 struct inode * inode = file_inode(file);
1249 uid_t loginuid;
1250 kuid_t kloginuid;
1251 int rv;
1252
1253 rcu_read_lock();
1254 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1255 rcu_read_unlock();
1256 return -EPERM;
1257 }
1258 rcu_read_unlock();
1259
1260 if (*ppos != 0) {
1261 /* No partial writes. */
1262 return -EINVAL;
1263 }
1264
1265 rv = kstrtou32_from_user(buf, count, 10, &loginuid);
1266 if (rv < 0)
1267 return rv;
1268
1269 /* is userspace tring to explicitly UNSET the loginuid? */
1270 if (loginuid == AUDIT_UID_UNSET) {
1271 kloginuid = INVALID_UID;
1272 } else {
1273 kloginuid = make_kuid(file->f_cred->user_ns, loginuid);
1274 if (!uid_valid(kloginuid))
1275 return -EINVAL;
1276 }
1277
1278 rv = audit_set_loginuid(kloginuid);
1279 if (rv < 0)
1280 return rv;
1281 return count;
1282}
1283
1284static const struct file_operations proc_loginuid_operations = {
1285 .read = proc_loginuid_read,
1286 .write = proc_loginuid_write,
1287 .llseek = generic_file_llseek,
1288};
1289
1290static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1291 size_t count, loff_t *ppos)
1292{
1293 struct inode * inode = file_inode(file);
1294 struct task_struct *task = get_proc_task(inode);
1295 ssize_t length;
1296 char tmpbuf[TMPBUFLEN];
1297
1298 if (!task)
1299 return -ESRCH;
1300 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1301 audit_get_sessionid(task));
1302 put_task_struct(task);
1303 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1304}
1305
1306static const struct file_operations proc_sessionid_operations = {
1307 .read = proc_sessionid_read,
1308 .llseek = generic_file_llseek,
1309};
1310#endif
1311
1312#ifdef CONFIG_FAULT_INJECTION
1313static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1314 size_t count, loff_t *ppos)
1315{
1316 struct task_struct *task = get_proc_task(file_inode(file));
1317 char buffer[PROC_NUMBUF];
1318 size_t len;
1319 int make_it_fail;
1320
1321 if (!task)
1322 return -ESRCH;
1323 make_it_fail = task->make_it_fail;
1324 put_task_struct(task);
1325
1326 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1327
1328 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1329}
1330
1331static ssize_t proc_fault_inject_write(struct file * file,
1332 const char __user * buf, size_t count, loff_t *ppos)
1333{
1334 struct task_struct *task;
1335 char buffer[PROC_NUMBUF];
1336 int make_it_fail;
1337 int rv;
1338
1339 if (!capable(CAP_SYS_RESOURCE))
1340 return -EPERM;
1341 memset(buffer, 0, sizeof(buffer));
1342 if (count > sizeof(buffer) - 1)
1343 count = sizeof(buffer) - 1;
1344 if (copy_from_user(buffer, buf, count))
1345 return -EFAULT;
1346 rv = kstrtoint(strstrip(buffer), 0, &make_it_fail);
1347 if (rv < 0)
1348 return rv;
1349 if (make_it_fail < 0 || make_it_fail > 1)
1350 return -EINVAL;
1351
1352 task = get_proc_task(file_inode(file));
1353 if (!task)
1354 return -ESRCH;
1355 task->make_it_fail = make_it_fail;
1356 put_task_struct(task);
1357
1358 return count;
1359}
1360
1361static const struct file_operations proc_fault_inject_operations = {
1362 .read = proc_fault_inject_read,
1363 .write = proc_fault_inject_write,
1364 .llseek = generic_file_llseek,
1365};
1366#endif
1367
1368
1369#ifdef CONFIG_SCHED_DEBUG
1370/*
1371 * Print out various scheduling related per-task fields:
1372 */
1373static int sched_show(struct seq_file *m, void *v)
1374{
1375 struct inode *inode = m->private;
1376 struct task_struct *p;
1377
1378 p = get_proc_task(inode);
1379 if (!p)
1380 return -ESRCH;
1381 proc_sched_show_task(p, m);
1382
1383 put_task_struct(p);
1384
1385 return 0;
1386}
1387
1388static ssize_t
1389sched_write(struct file *file, const char __user *buf,
1390 size_t count, loff_t *offset)
1391{
1392 struct inode *inode = file_inode(file);
1393 struct task_struct *p;
1394
1395 p = get_proc_task(inode);
1396 if (!p)
1397 return -ESRCH;
1398 proc_sched_set_task(p);
1399
1400 put_task_struct(p);
1401
1402 return count;
1403}
1404
1405static int sched_open(struct inode *inode, struct file *filp)
1406{
1407 return single_open(filp, sched_show, inode);
1408}
1409
1410static const struct file_operations proc_pid_sched_operations = {
1411 .open = sched_open,
1412 .read = seq_read,
1413 .write = sched_write,
1414 .llseek = seq_lseek,
1415 .release = single_release,
1416};
1417
1418#endif
1419
1420#ifdef CONFIG_SCHED_AUTOGROUP
1421/*
1422 * Print out autogroup related information:
1423 */
1424static int sched_autogroup_show(struct seq_file *m, void *v)
1425{
1426 struct inode *inode = m->private;
1427 struct task_struct *p;
1428
1429 p = get_proc_task(inode);
1430 if (!p)
1431 return -ESRCH;
1432 proc_sched_autogroup_show_task(p, m);
1433
1434 put_task_struct(p);
1435
1436 return 0;
1437}
1438
1439static ssize_t
1440sched_autogroup_write(struct file *file, const char __user *buf,
1441 size_t count, loff_t *offset)
1442{
1443 struct inode *inode = file_inode(file);
1444 struct task_struct *p;
1445 char buffer[PROC_NUMBUF];
1446 int nice;
1447 int err;
1448
1449 memset(buffer, 0, sizeof(buffer));
1450 if (count > sizeof(buffer) - 1)
1451 count = sizeof(buffer) - 1;
1452 if (copy_from_user(buffer, buf, count))
1453 return -EFAULT;
1454
1455 err = kstrtoint(strstrip(buffer), 0, &nice);
1456 if (err < 0)
1457 return err;
1458
1459 p = get_proc_task(inode);
1460 if (!p)
1461 return -ESRCH;
1462
1463 err = proc_sched_autogroup_set_nice(p, nice);
1464 if (err)
1465 count = err;
1466
1467 put_task_struct(p);
1468
1469 return count;
1470}
1471
1472static int sched_autogroup_open(struct inode *inode, struct file *filp)
1473{
1474 int ret;
1475
1476 ret = single_open(filp, sched_autogroup_show, NULL);
1477 if (!ret) {
1478 struct seq_file *m = filp->private_data;
1479
1480 m->private = inode;
1481 }
1482 return ret;
1483}
1484
1485static const struct file_operations proc_pid_sched_autogroup_operations = {
1486 .open = sched_autogroup_open,
1487 .read = seq_read,
1488 .write = sched_autogroup_write,
1489 .llseek = seq_lseek,
1490 .release = single_release,
1491};
1492
1493#endif /* CONFIG_SCHED_AUTOGROUP */
1494
1495static ssize_t comm_write(struct file *file, const char __user *buf,
1496 size_t count, loff_t *offset)
1497{
1498 struct inode *inode = file_inode(file);
1499 struct task_struct *p;
1500 char buffer[TASK_COMM_LEN];
1501 const size_t maxlen = sizeof(buffer) - 1;
1502
1503 memset(buffer, 0, sizeof(buffer));
1504 if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
1505 return -EFAULT;
1506
1507 p = get_proc_task(inode);
1508 if (!p)
1509 return -ESRCH;
1510
1511 if (same_thread_group(current, p))
1512 set_task_comm(p, buffer);
1513 else
1514 count = -EINVAL;
1515
1516 put_task_struct(p);
1517
1518 return count;
1519}
1520
1521static int comm_show(struct seq_file *m, void *v)
1522{
1523 struct inode *inode = m->private;
1524 struct task_struct *p;
1525
1526 p = get_proc_task(inode);
1527 if (!p)
1528 return -ESRCH;
1529
1530 task_lock(p);
1531 seq_printf(m, "%s\n", p->comm);
1532 task_unlock(p);
1533
1534 put_task_struct(p);
1535
1536 return 0;
1537}
1538
1539static int comm_open(struct inode *inode, struct file *filp)
1540{
1541 return single_open(filp, comm_show, inode);
1542}
1543
1544static const struct file_operations proc_pid_set_comm_operations = {
1545 .open = comm_open,
1546 .read = seq_read,
1547 .write = comm_write,
1548 .llseek = seq_lseek,
1549 .release = single_release,
1550};
1551
1552static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1553{
1554 struct task_struct *task;
1555 struct mm_struct *mm;
1556 struct file *exe_file;
1557
1558 task = get_proc_task(d_inode(dentry));
1559 if (!task)
1560 return -ENOENT;
1561 mm = get_task_mm(task);
1562 put_task_struct(task);
1563 if (!mm)
1564 return -ENOENT;
1565 exe_file = get_mm_exe_file(mm);
1566 mmput(mm);
1567 if (exe_file) {
1568 *exe_path = exe_file->f_path;
1569 path_get(&exe_file->f_path);
1570 fput(exe_file);
1571 return 0;
1572 } else
1573 return -ENOENT;
1574}
1575
1576static const char *proc_pid_get_link(struct dentry *dentry,
1577 struct inode *inode,
1578 struct delayed_call *done)
1579{
1580 struct path path;
1581 int error = -EACCES;
1582
1583 if (!dentry)
1584 return ERR_PTR(-ECHILD);
1585
1586 /* Are we allowed to snoop on the tasks file descriptors? */
1587 if (!proc_fd_access_allowed(inode))
1588 goto out;
1589
1590 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1591 if (error)
1592 goto out;
1593
1594 nd_jump_link(&path);
1595 return NULL;
1596out:
1597 return ERR_PTR(error);
1598}
1599
1600static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1601{
1602 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
1603 char *pathname;
1604 int len;
1605
1606 if (!tmp)
1607 return -ENOMEM;
1608
1609 pathname = d_path(path, tmp, PAGE_SIZE);
1610 len = PTR_ERR(pathname);
1611 if (IS_ERR(pathname))
1612 goto out;
1613 len = tmp + PAGE_SIZE - 1 - pathname;
1614
1615 if (len > buflen)
1616 len = buflen;
1617 if (copy_to_user(buffer, pathname, len))
1618 len = -EFAULT;
1619 out:
1620 free_page((unsigned long)tmp);
1621 return len;
1622}
1623
1624static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1625{
1626 int error = -EACCES;
1627 struct inode *inode = d_inode(dentry);
1628 struct path path;
1629
1630 /* Are we allowed to snoop on the tasks file descriptors? */
1631 if (!proc_fd_access_allowed(inode))
1632 goto out;
1633
1634 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1635 if (error)
1636 goto out;
1637
1638 error = do_proc_readlink(&path, buffer, buflen);
1639 path_put(&path);
1640out:
1641 return error;
1642}
1643
1644const struct inode_operations proc_pid_link_inode_operations = {
1645 .readlink = proc_pid_readlink,
1646 .get_link = proc_pid_get_link,
1647 .setattr = proc_setattr,
1648};
1649
1650
1651/* building an inode */
1652
1653struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
1654{
1655 struct inode * inode;
1656 struct proc_inode *ei;
1657 const struct cred *cred;
1658
1659 /* We need a new inode */
1660
1661 inode = new_inode(sb);
1662 if (!inode)
1663 goto out;
1664
1665 /* Common stuff */
1666 ei = PROC_I(inode);
1667 inode->i_ino = get_next_ino();
1668 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1669 inode->i_op = &proc_def_inode_operations;
1670
1671 /*
1672 * grab the reference to task.
1673 */
1674 ei->pid = get_task_pid(task, PIDTYPE_PID);
1675 if (!ei->pid)
1676 goto out_unlock;
1677
1678 if (task_dumpable(task)) {
1679 rcu_read_lock();
1680 cred = __task_cred(task);
1681 inode->i_uid = cred->euid;
1682 inode->i_gid = cred->egid;
1683 rcu_read_unlock();
1684 }
1685 security_task_to_inode(task, inode);
1686
1687out:
1688 return inode;
1689
1690out_unlock:
1691 iput(inode);
1692 return NULL;
1693}
1694
1695int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1696{
1697 struct inode *inode = d_inode(dentry);
1698 struct task_struct *task;
1699 const struct cred *cred;
1700 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
1701
1702 generic_fillattr(inode, stat);
1703
1704 rcu_read_lock();
1705 stat->uid = GLOBAL_ROOT_UID;
1706 stat->gid = GLOBAL_ROOT_GID;
1707 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1708 if (task) {
1709 if (!has_pid_permissions(pid, task, 2)) {
1710 rcu_read_unlock();
1711 /*
1712 * This doesn't prevent learning whether PID exists,
1713 * it only makes getattr() consistent with readdir().
1714 */
1715 return -ENOENT;
1716 }
1717 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1718 task_dumpable(task)) {
1719 cred = __task_cred(task);
1720 stat->uid = cred->euid;
1721 stat->gid = cred->egid;
1722 }
1723 }
1724 rcu_read_unlock();
1725 return 0;
1726}
1727
1728/* dentry stuff */
1729
1730/*
1731 * Exceptional case: normally we are not allowed to unhash a busy
1732 * directory. In this case, however, we can do it - no aliasing problems
1733 * due to the way we treat inodes.
1734 *
1735 * Rewrite the inode's ownerships here because the owning task may have
1736 * performed a setuid(), etc.
1737 *
1738 * Before the /proc/pid/status file was created the only way to read
1739 * the effective uid of a /process was to stat /proc/pid. Reading
1740 * /proc/pid/status is slow enough that procps and other packages
1741 * kept stating /proc/pid. To keep the rules in /proc simple I have
1742 * made this apply to all per process world readable and executable
1743 * directories.
1744 */
1745int pid_revalidate(struct dentry *dentry, unsigned int flags)
1746{
1747 struct inode *inode;
1748 struct task_struct *task;
1749 const struct cred *cred;
1750
1751 if (flags & LOOKUP_RCU)
1752 return -ECHILD;
1753
1754 inode = d_inode(dentry);
1755 task = get_proc_task(inode);
1756
1757 if (task) {
1758 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1759 task_dumpable(task)) {
1760 rcu_read_lock();
1761 cred = __task_cred(task);
1762 inode->i_uid = cred->euid;
1763 inode->i_gid = cred->egid;
1764 rcu_read_unlock();
1765 } else {
1766 inode->i_uid = GLOBAL_ROOT_UID;
1767 inode->i_gid = GLOBAL_ROOT_GID;
1768 }
1769 inode->i_mode &= ~(S_ISUID | S_ISGID);
1770 security_task_to_inode(task, inode);
1771 put_task_struct(task);
1772 return 1;
1773 }
1774 return 0;
1775}
1776
1777static inline bool proc_inode_is_dead(struct inode *inode)
1778{
1779 return !proc_pid(inode)->tasks[PIDTYPE_PID].first;
1780}
1781
1782int pid_delete_dentry(const struct dentry *dentry)
1783{
1784 /* Is the task we represent dead?
1785 * If so, then don't put the dentry on the lru list,
1786 * kill it immediately.
1787 */
1788 return proc_inode_is_dead(d_inode(dentry));
1789}
1790
1791const struct dentry_operations pid_dentry_operations =
1792{
1793 .d_revalidate = pid_revalidate,
1794 .d_delete = pid_delete_dentry,
1795};
1796
1797/* Lookups */
1798
1799/*
1800 * Fill a directory entry.
1801 *
1802 * If possible create the dcache entry and derive our inode number and
1803 * file type from dcache entry.
1804 *
1805 * Since all of the proc inode numbers are dynamically generated, the inode
1806 * numbers do not exist until the inode is cache. This means creating the
1807 * the dcache entry in readdir is necessary to keep the inode numbers
1808 * reported by readdir in sync with the inode numbers reported
1809 * by stat.
1810 */
1811bool proc_fill_cache(struct file *file, struct dir_context *ctx,
1812 const char *name, int len,
1813 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1814{
1815 struct dentry *child, *dir = file->f_path.dentry;
1816 struct qstr qname = QSTR_INIT(name, len);
1817 struct inode *inode;
1818 unsigned type;
1819 ino_t ino;
1820
1821 child = d_hash_and_lookup(dir, &qname);
1822 if (!child) {
1823 child = d_alloc(dir, &qname);
1824 if (!child)
1825 goto end_instantiate;
1826 if (instantiate(d_inode(dir), child, task, ptr) < 0) {
1827 dput(child);
1828 goto end_instantiate;
1829 }
1830 }
1831 inode = d_inode(child);
1832 ino = inode->i_ino;
1833 type = inode->i_mode >> 12;
1834 dput(child);
1835 return dir_emit(ctx, name, len, ino, type);
1836
1837end_instantiate:
1838 return dir_emit(ctx, name, len, 1, DT_UNKNOWN);
1839}
1840
1841/*
1842 * dname_to_vma_addr - maps a dentry name into two unsigned longs
1843 * which represent vma start and end addresses.
1844 */
1845static int dname_to_vma_addr(struct dentry *dentry,
1846 unsigned long *start, unsigned long *end)
1847{
1848 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
1849 return -EINVAL;
1850
1851 return 0;
1852}
1853
1854static int map_files_d_revalidate(struct dentry *dentry, unsigned int flags)
1855{
1856 unsigned long vm_start, vm_end;
1857 bool exact_vma_exists = false;
1858 struct mm_struct *mm = NULL;
1859 struct task_struct *task;
1860 const struct cred *cred;
1861 struct inode *inode;
1862 int status = 0;
1863
1864 if (flags & LOOKUP_RCU)
1865 return -ECHILD;
1866
1867 inode = d_inode(dentry);
1868 task = get_proc_task(inode);
1869 if (!task)
1870 goto out_notask;
1871
1872 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS);
1873 if (IS_ERR_OR_NULL(mm))
1874 goto out;
1875
1876 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
1877 down_read(&mm->mmap_sem);
1878 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
1879 up_read(&mm->mmap_sem);
1880 }
1881
1882 mmput(mm);
1883
1884 if (exact_vma_exists) {
1885 if (task_dumpable(task)) {
1886 rcu_read_lock();
1887 cred = __task_cred(task);
1888 inode->i_uid = cred->euid;
1889 inode->i_gid = cred->egid;
1890 rcu_read_unlock();
1891 } else {
1892 inode->i_uid = GLOBAL_ROOT_UID;
1893 inode->i_gid = GLOBAL_ROOT_GID;
1894 }
1895 security_task_to_inode(task, inode);
1896 status = 1;
1897 }
1898
1899out:
1900 put_task_struct(task);
1901
1902out_notask:
1903 return status;
1904}
1905
1906static const struct dentry_operations tid_map_files_dentry_operations = {
1907 .d_revalidate = map_files_d_revalidate,
1908 .d_delete = pid_delete_dentry,
1909};
1910
1911static int map_files_get_link(struct dentry *dentry, struct path *path)
1912{
1913 unsigned long vm_start, vm_end;
1914 struct vm_area_struct *vma;
1915 struct task_struct *task;
1916 struct mm_struct *mm;
1917 int rc;
1918
1919 rc = -ENOENT;
1920 task = get_proc_task(d_inode(dentry));
1921 if (!task)
1922 goto out;
1923
1924 mm = get_task_mm(task);
1925 put_task_struct(task);
1926 if (!mm)
1927 goto out;
1928
1929 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
1930 if (rc)
1931 goto out_mmput;
1932
1933 rc = -ENOENT;
1934 down_read(&mm->mmap_sem);
1935 vma = find_exact_vma(mm, vm_start, vm_end);
1936 if (vma && vma->vm_file) {
1937 *path = vma->vm_file->f_path;
1938 path_get(path);
1939 rc = 0;
1940 }
1941 up_read(&mm->mmap_sem);
1942
1943out_mmput:
1944 mmput(mm);
1945out:
1946 return rc;
1947}
1948
1949struct map_files_info {
1950 fmode_t mode;
1951 unsigned long len;
1952 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
1953};
1954
1955/*
1956 * Only allow CAP_SYS_ADMIN to follow the links, due to concerns about how the
1957 * symlinks may be used to bypass permissions on ancestor directories in the
1958 * path to the file in question.
1959 */
1960static const char *
1961proc_map_files_get_link(struct dentry *dentry,
1962 struct inode *inode,
1963 struct delayed_call *done)
1964{
1965 if (!capable(CAP_SYS_ADMIN))
1966 return ERR_PTR(-EPERM);
1967
1968 return proc_pid_get_link(dentry, inode, done);
1969}
1970
1971/*
1972 * Identical to proc_pid_link_inode_operations except for get_link()
1973 */
1974static const struct inode_operations proc_map_files_link_inode_operations = {
1975 .readlink = proc_pid_readlink,
1976 .get_link = proc_map_files_get_link,
1977 .setattr = proc_setattr,
1978};
1979
1980static int
1981proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
1982 struct task_struct *task, const void *ptr)
1983{
1984 fmode_t mode = (fmode_t)(unsigned long)ptr;
1985 struct proc_inode *ei;
1986 struct inode *inode;
1987
1988 inode = proc_pid_make_inode(dir->i_sb, task);
1989 if (!inode)
1990 return -ENOENT;
1991
1992 ei = PROC_I(inode);
1993 ei->op.proc_get_link = map_files_get_link;
1994
1995 inode->i_op = &proc_map_files_link_inode_operations;
1996 inode->i_size = 64;
1997 inode->i_mode = S_IFLNK;
1998
1999 if (mode & FMODE_READ)
2000 inode->i_mode |= S_IRUSR;
2001 if (mode & FMODE_WRITE)
2002 inode->i_mode |= S_IWUSR;
2003
2004 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2005 d_add(dentry, inode);
2006
2007 return 0;
2008}
2009
2010static struct dentry *proc_map_files_lookup(struct inode *dir,
2011 struct dentry *dentry, unsigned int flags)
2012{
2013 unsigned long vm_start, vm_end;
2014 struct vm_area_struct *vma;
2015 struct task_struct *task;
2016 int result;
2017 struct mm_struct *mm;
2018
2019 result = -ENOENT;
2020 task = get_proc_task(dir);
2021 if (!task)
2022 goto out;
2023
2024 result = -EACCES;
2025 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2026 goto out_put_task;
2027
2028 result = -ENOENT;
2029 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2030 goto out_put_task;
2031
2032 mm = get_task_mm(task);
2033 if (!mm)
2034 goto out_put_task;
2035
2036 down_read(&mm->mmap_sem);
2037 vma = find_exact_vma(mm, vm_start, vm_end);
2038 if (!vma)
2039 goto out_no_vma;
2040
2041 if (vma->vm_file)
2042 result = proc_map_files_instantiate(dir, dentry, task,
2043 (void *)(unsigned long)vma->vm_file->f_mode);
2044
2045out_no_vma:
2046 up_read(&mm->mmap_sem);
2047 mmput(mm);
2048out_put_task:
2049 put_task_struct(task);
2050out:
2051 return ERR_PTR(result);
2052}
2053
2054static const struct inode_operations proc_map_files_inode_operations = {
2055 .lookup = proc_map_files_lookup,
2056 .permission = proc_fd_permission,
2057 .setattr = proc_setattr,
2058};
2059
2060static int
2061proc_map_files_readdir(struct file *file, struct dir_context *ctx)
2062{
2063 struct vm_area_struct *vma;
2064 struct task_struct *task;
2065 struct mm_struct *mm;
2066 unsigned long nr_files, pos, i;
2067 struct flex_array *fa = NULL;
2068 struct map_files_info info;
2069 struct map_files_info *p;
2070 int ret;
2071
2072 ret = -ENOENT;
2073 task = get_proc_task(file_inode(file));
2074 if (!task)
2075 goto out;
2076
2077 ret = -EACCES;
2078 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
2079 goto out_put_task;
2080
2081 ret = 0;
2082 if (!dir_emit_dots(file, ctx))
2083 goto out_put_task;
2084
2085 mm = get_task_mm(task);
2086 if (!mm)
2087 goto out_put_task;
2088 down_read(&mm->mmap_sem);
2089
2090 nr_files = 0;
2091
2092 /*
2093 * We need two passes here:
2094 *
2095 * 1) Collect vmas of mapped files with mmap_sem taken
2096 * 2) Release mmap_sem and instantiate entries
2097 *
2098 * otherwise we get lockdep complained, since filldir()
2099 * routine might require mmap_sem taken in might_fault().
2100 */
2101
2102 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2103 if (vma->vm_file && ++pos > ctx->pos)
2104 nr_files++;
2105 }
2106
2107 if (nr_files) {
2108 fa = flex_array_alloc(sizeof(info), nr_files,
2109 GFP_KERNEL);
2110 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2111 GFP_KERNEL)) {
2112 ret = -ENOMEM;
2113 if (fa)
2114 flex_array_free(fa);
2115 up_read(&mm->mmap_sem);
2116 mmput(mm);
2117 goto out_put_task;
2118 }
2119 for (i = 0, vma = mm->mmap, pos = 2; vma;
2120 vma = vma->vm_next) {
2121 if (!vma->vm_file)
2122 continue;
2123 if (++pos <= ctx->pos)
2124 continue;
2125
2126 info.mode = vma->vm_file->f_mode;
2127 info.len = snprintf(info.name,
2128 sizeof(info.name), "%lx-%lx",
2129 vma->vm_start, vma->vm_end);
2130 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2131 BUG();
2132 }
2133 }
2134 up_read(&mm->mmap_sem);
2135
2136 for (i = 0; i < nr_files; i++) {
2137 p = flex_array_get(fa, i);
2138 if (!proc_fill_cache(file, ctx,
2139 p->name, p->len,
2140 proc_map_files_instantiate,
2141 task,
2142 (void *)(unsigned long)p->mode))
2143 break;
2144 ctx->pos++;
2145 }
2146 if (fa)
2147 flex_array_free(fa);
2148 mmput(mm);
2149
2150out_put_task:
2151 put_task_struct(task);
2152out:
2153 return ret;
2154}
2155
2156static const struct file_operations proc_map_files_operations = {
2157 .read = generic_read_dir,
2158 .iterate = proc_map_files_readdir,
2159 .llseek = default_llseek,
2160};
2161
2162#ifdef CONFIG_CHECKPOINT_RESTORE
2163struct timers_private {
2164 struct pid *pid;
2165 struct task_struct *task;
2166 struct sighand_struct *sighand;
2167 struct pid_namespace *ns;
2168 unsigned long flags;
2169};
2170
2171static void *timers_start(struct seq_file *m, loff_t *pos)
2172{
2173 struct timers_private *tp = m->private;
2174
2175 tp->task = get_pid_task(tp->pid, PIDTYPE_PID);
2176 if (!tp->task)
2177 return ERR_PTR(-ESRCH);
2178
2179 tp->sighand = lock_task_sighand(tp->task, &tp->flags);
2180 if (!tp->sighand)
2181 return ERR_PTR(-ESRCH);
2182
2183 return seq_list_start(&tp->task->signal->posix_timers, *pos);
2184}
2185
2186static void *timers_next(struct seq_file *m, void *v, loff_t *pos)
2187{
2188 struct timers_private *tp = m->private;
2189 return seq_list_next(v, &tp->task->signal->posix_timers, pos);
2190}
2191
2192static void timers_stop(struct seq_file *m, void *v)
2193{
2194 struct timers_private *tp = m->private;
2195
2196 if (tp->sighand) {
2197 unlock_task_sighand(tp->task, &tp->flags);
2198 tp->sighand = NULL;
2199 }
2200
2201 if (tp->task) {
2202 put_task_struct(tp->task);
2203 tp->task = NULL;
2204 }
2205}
2206
2207static int show_timer(struct seq_file *m, void *v)
2208{
2209 struct k_itimer *timer;
2210 struct timers_private *tp = m->private;
2211 int notify;
2212 static const char * const nstr[] = {
2213 [SIGEV_SIGNAL] = "signal",
2214 [SIGEV_NONE] = "none",
2215 [SIGEV_THREAD] = "thread",
2216 };
2217
2218 timer = list_entry((struct list_head *)v, struct k_itimer, list);
2219 notify = timer->it_sigev_notify;
2220
2221 seq_printf(m, "ID: %d\n", timer->it_id);
2222 seq_printf(m, "signal: %d/%p\n",
2223 timer->sigq->info.si_signo,
2224 timer->sigq->info.si_value.sival_ptr);
2225 seq_printf(m, "notify: %s/%s.%d\n",
2226 nstr[notify & ~SIGEV_THREAD_ID],
2227 (notify & SIGEV_THREAD_ID) ? "tid" : "pid",
2228 pid_nr_ns(timer->it_pid, tp->ns));
2229 seq_printf(m, "ClockID: %d\n", timer->it_clock);
2230
2231 return 0;
2232}
2233
2234static const struct seq_operations proc_timers_seq_ops = {
2235 .start = timers_start,
2236 .next = timers_next,
2237 .stop = timers_stop,
2238 .show = show_timer,
2239};
2240
2241static int proc_timers_open(struct inode *inode, struct file *file)
2242{
2243 struct timers_private *tp;
2244
2245 tp = __seq_open_private(file, &proc_timers_seq_ops,
2246 sizeof(struct timers_private));
2247 if (!tp)
2248 return -ENOMEM;
2249
2250 tp->pid = proc_pid(inode);
2251 tp->ns = inode->i_sb->s_fs_info;
2252 return 0;
2253}
2254
2255static const struct file_operations proc_timers_operations = {
2256 .open = proc_timers_open,
2257 .read = seq_read,
2258 .llseek = seq_lseek,
2259 .release = seq_release_private,
2260};
2261#endif
2262
2263static ssize_t timerslack_ns_write(struct file *file, const char __user *buf,
2264 size_t count, loff_t *offset)
2265{
2266 struct inode *inode = file_inode(file);
2267 struct task_struct *p;
2268 u64 slack_ns;
2269 int err;
2270
2271 err = kstrtoull_from_user(buf, count, 10, &slack_ns);
2272 if (err < 0)
2273 return err;
2274
2275 p = get_proc_task(inode);
2276 if (!p)
2277 return -ESRCH;
2278
2279 if (ptrace_may_access(p, PTRACE_MODE_ATTACH_FSCREDS)) {
2280 task_lock(p);
2281 if (slack_ns == 0)
2282 p->timer_slack_ns = p->default_timer_slack_ns;
2283 else
2284 p->timer_slack_ns = slack_ns;
2285 task_unlock(p);
2286 } else
2287 count = -EPERM;
2288
2289 put_task_struct(p);
2290
2291 return count;
2292}
2293
2294static int timerslack_ns_show(struct seq_file *m, void *v)
2295{
2296 struct inode *inode = m->private;
2297 struct task_struct *p;
2298 int err = 0;
2299
2300 p = get_proc_task(inode);
2301 if (!p)
2302 return -ESRCH;
2303
2304 if (ptrace_may_access(p, PTRACE_MODE_ATTACH_FSCREDS)) {
2305 task_lock(p);
2306 seq_printf(m, "%llu\n", p->timer_slack_ns);
2307 task_unlock(p);
2308 } else
2309 err = -EPERM;
2310
2311 put_task_struct(p);
2312
2313 return err;
2314}
2315
2316static int timerslack_ns_open(struct inode *inode, struct file *filp)
2317{
2318 return single_open(filp, timerslack_ns_show, inode);
2319}
2320
2321static const struct file_operations proc_pid_set_timerslack_ns_operations = {
2322 .open = timerslack_ns_open,
2323 .read = seq_read,
2324 .write = timerslack_ns_write,
2325 .llseek = seq_lseek,
2326 .release = single_release,
2327};
2328
2329static int proc_pident_instantiate(struct inode *dir,
2330 struct dentry *dentry, struct task_struct *task, const void *ptr)
2331{
2332 const struct pid_entry *p = ptr;
2333 struct inode *inode;
2334 struct proc_inode *ei;
2335
2336 inode = proc_pid_make_inode(dir->i_sb, task);
2337 if (!inode)
2338 goto out;
2339
2340 ei = PROC_I(inode);
2341 inode->i_mode = p->mode;
2342 if (S_ISDIR(inode->i_mode))
2343 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2344 if (p->iop)
2345 inode->i_op = p->iop;
2346 if (p->fop)
2347 inode->i_fop = p->fop;
2348 ei->op = p->op;
2349 d_set_d_op(dentry, &pid_dentry_operations);
2350 d_add(dentry, inode);
2351 /* Close the race of the process dying before we return the dentry */
2352 if (pid_revalidate(dentry, 0))
2353 return 0;
2354out:
2355 return -ENOENT;
2356}
2357
2358static struct dentry *proc_pident_lookup(struct inode *dir,
2359 struct dentry *dentry,
2360 const struct pid_entry *ents,
2361 unsigned int nents)
2362{
2363 int error;
2364 struct task_struct *task = get_proc_task(dir);
2365 const struct pid_entry *p, *last;
2366
2367 error = -ENOENT;
2368
2369 if (!task)
2370 goto out_no_task;
2371
2372 /*
2373 * Yes, it does not scale. And it should not. Don't add
2374 * new entries into /proc/<tgid>/ without very good reasons.
2375 */
2376 last = &ents[nents - 1];
2377 for (p = ents; p <= last; p++) {
2378 if (p->len != dentry->d_name.len)
2379 continue;
2380 if (!memcmp(dentry->d_name.name, p->name, p->len))
2381 break;
2382 }
2383 if (p > last)
2384 goto out;
2385
2386 error = proc_pident_instantiate(dir, dentry, task, p);
2387out:
2388 put_task_struct(task);
2389out_no_task:
2390 return ERR_PTR(error);
2391}
2392
2393static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
2394 const struct pid_entry *ents, unsigned int nents)
2395{
2396 struct task_struct *task = get_proc_task(file_inode(file));
2397 const struct pid_entry *p;
2398
2399 if (!task)
2400 return -ENOENT;
2401
2402 if (!dir_emit_dots(file, ctx))
2403 goto out;
2404
2405 if (ctx->pos >= nents + 2)
2406 goto out;
2407
2408 for (p = ents + (ctx->pos - 2); p <= ents + nents - 1; p++) {
2409 if (!proc_fill_cache(file, ctx, p->name, p->len,
2410 proc_pident_instantiate, task, p))
2411 break;
2412 ctx->pos++;
2413 }
2414out:
2415 put_task_struct(task);
2416 return 0;
2417}
2418
2419#ifdef CONFIG_SECURITY
2420static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2421 size_t count, loff_t *ppos)
2422{
2423 struct inode * inode = file_inode(file);
2424 char *p = NULL;
2425 ssize_t length;
2426 struct task_struct *task = get_proc_task(inode);
2427
2428 if (!task)
2429 return -ESRCH;
2430
2431 length = security_getprocattr(task,
2432 (char*)file->f_path.dentry->d_name.name,
2433 &p);
2434 put_task_struct(task);
2435 if (length > 0)
2436 length = simple_read_from_buffer(buf, count, ppos, p, length);
2437 kfree(p);
2438 return length;
2439}
2440
2441static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2442 size_t count, loff_t *ppos)
2443{
2444 struct inode * inode = file_inode(file);
2445 void *page;
2446 ssize_t length;
2447 struct task_struct *task = get_proc_task(inode);
2448
2449 length = -ESRCH;
2450 if (!task)
2451 goto out_no_task;
2452 if (count > PAGE_SIZE)
2453 count = PAGE_SIZE;
2454
2455 /* No partial writes. */
2456 length = -EINVAL;
2457 if (*ppos != 0)
2458 goto out;
2459
2460 page = memdup_user(buf, count);
2461 if (IS_ERR(page)) {
2462 length = PTR_ERR(page);
2463 goto out;
2464 }
2465
2466 /* Guard against adverse ptrace interaction */
2467 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
2468 if (length < 0)
2469 goto out_free;
2470
2471 length = security_setprocattr(task,
2472 (char*)file->f_path.dentry->d_name.name,
2473 page, count);
2474 mutex_unlock(&task->signal->cred_guard_mutex);
2475out_free:
2476 kfree(page);
2477out:
2478 put_task_struct(task);
2479out_no_task:
2480 return length;
2481}
2482
2483static const struct file_operations proc_pid_attr_operations = {
2484 .read = proc_pid_attr_read,
2485 .write = proc_pid_attr_write,
2486 .llseek = generic_file_llseek,
2487};
2488
2489static const struct pid_entry attr_dir_stuff[] = {
2490 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2491 REG("prev", S_IRUGO, proc_pid_attr_operations),
2492 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2493 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2494 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2495 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2496};
2497
2498static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
2499{
2500 return proc_pident_readdir(file, ctx,
2501 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2502}
2503
2504static const struct file_operations proc_attr_dir_operations = {
2505 .read = generic_read_dir,
2506 .iterate = proc_attr_dir_readdir,
2507 .llseek = default_llseek,
2508};
2509
2510static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2511 struct dentry *dentry, unsigned int flags)
2512{
2513 return proc_pident_lookup(dir, dentry,
2514 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2515}
2516
2517static const struct inode_operations proc_attr_dir_inode_operations = {
2518 .lookup = proc_attr_dir_lookup,
2519 .getattr = pid_getattr,
2520 .setattr = proc_setattr,
2521};
2522
2523#endif
2524
2525#ifdef CONFIG_ELF_CORE
2526static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2527 size_t count, loff_t *ppos)
2528{
2529 struct task_struct *task = get_proc_task(file_inode(file));
2530 struct mm_struct *mm;
2531 char buffer[PROC_NUMBUF];
2532 size_t len;
2533 int ret;
2534
2535 if (!task)
2536 return -ESRCH;
2537
2538 ret = 0;
2539 mm = get_task_mm(task);
2540 if (mm) {
2541 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2542 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2543 MMF_DUMP_FILTER_SHIFT));
2544 mmput(mm);
2545 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2546 }
2547
2548 put_task_struct(task);
2549
2550 return ret;
2551}
2552
2553static ssize_t proc_coredump_filter_write(struct file *file,
2554 const char __user *buf,
2555 size_t count,
2556 loff_t *ppos)
2557{
2558 struct task_struct *task;
2559 struct mm_struct *mm;
2560 unsigned int val;
2561 int ret;
2562 int i;
2563 unsigned long mask;
2564
2565 ret = kstrtouint_from_user(buf, count, 0, &val);
2566 if (ret < 0)
2567 return ret;
2568
2569 ret = -ESRCH;
2570 task = get_proc_task(file_inode(file));
2571 if (!task)
2572 goto out_no_task;
2573
2574 mm = get_task_mm(task);
2575 if (!mm)
2576 goto out_no_mm;
2577 ret = 0;
2578
2579 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2580 if (val & mask)
2581 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2582 else
2583 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2584 }
2585
2586 mmput(mm);
2587 out_no_mm:
2588 put_task_struct(task);
2589 out_no_task:
2590 if (ret < 0)
2591 return ret;
2592 return count;
2593}
2594
2595static const struct file_operations proc_coredump_filter_operations = {
2596 .read = proc_coredump_filter_read,
2597 .write = proc_coredump_filter_write,
2598 .llseek = generic_file_llseek,
2599};
2600#endif
2601
2602#ifdef CONFIG_TASK_IO_ACCOUNTING
2603static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
2604{
2605 struct task_io_accounting acct = task->ioac;
2606 unsigned long flags;
2607 int result;
2608
2609 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2610 if (result)
2611 return result;
2612
2613 if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
2614 result = -EACCES;
2615 goto out_unlock;
2616 }
2617
2618 if (whole && lock_task_sighand(task, &flags)) {
2619 struct task_struct *t = task;
2620
2621 task_io_accounting_add(&acct, &task->signal->ioac);
2622 while_each_thread(task, t)
2623 task_io_accounting_add(&acct, &t->ioac);
2624
2625 unlock_task_sighand(task, &flags);
2626 }
2627 seq_printf(m,
2628 "rchar: %llu\n"
2629 "wchar: %llu\n"
2630 "syscr: %llu\n"
2631 "syscw: %llu\n"
2632 "read_bytes: %llu\n"
2633 "write_bytes: %llu\n"
2634 "cancelled_write_bytes: %llu\n",
2635 (unsigned long long)acct.rchar,
2636 (unsigned long long)acct.wchar,
2637 (unsigned long long)acct.syscr,
2638 (unsigned long long)acct.syscw,
2639 (unsigned long long)acct.read_bytes,
2640 (unsigned long long)acct.write_bytes,
2641 (unsigned long long)acct.cancelled_write_bytes);
2642 result = 0;
2643
2644out_unlock:
2645 mutex_unlock(&task->signal->cred_guard_mutex);
2646 return result;
2647}
2648
2649static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2650 struct pid *pid, struct task_struct *task)
2651{
2652 return do_io_accounting(task, m, 0);
2653}
2654
2655static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
2656 struct pid *pid, struct task_struct *task)
2657{
2658 return do_io_accounting(task, m, 1);
2659}
2660#endif /* CONFIG_TASK_IO_ACCOUNTING */
2661
2662#ifdef CONFIG_USER_NS
2663static int proc_id_map_open(struct inode *inode, struct file *file,
2664 const struct seq_operations *seq_ops)
2665{
2666 struct user_namespace *ns = NULL;
2667 struct task_struct *task;
2668 struct seq_file *seq;
2669 int ret = -EINVAL;
2670
2671 task = get_proc_task(inode);
2672 if (task) {
2673 rcu_read_lock();
2674 ns = get_user_ns(task_cred_xxx(task, user_ns));
2675 rcu_read_unlock();
2676 put_task_struct(task);
2677 }
2678 if (!ns)
2679 goto err;
2680
2681 ret = seq_open(file, seq_ops);
2682 if (ret)
2683 goto err_put_ns;
2684
2685 seq = file->private_data;
2686 seq->private = ns;
2687
2688 return 0;
2689err_put_ns:
2690 put_user_ns(ns);
2691err:
2692 return ret;
2693}
2694
2695static int proc_id_map_release(struct inode *inode, struct file *file)
2696{
2697 struct seq_file *seq = file->private_data;
2698 struct user_namespace *ns = seq->private;
2699 put_user_ns(ns);
2700 return seq_release(inode, file);
2701}
2702
2703static int proc_uid_map_open(struct inode *inode, struct file *file)
2704{
2705 return proc_id_map_open(inode, file, &proc_uid_seq_operations);
2706}
2707
2708static int proc_gid_map_open(struct inode *inode, struct file *file)
2709{
2710 return proc_id_map_open(inode, file, &proc_gid_seq_operations);
2711}
2712
2713static int proc_projid_map_open(struct inode *inode, struct file *file)
2714{
2715 return proc_id_map_open(inode, file, &proc_projid_seq_operations);
2716}
2717
2718static const struct file_operations proc_uid_map_operations = {
2719 .open = proc_uid_map_open,
2720 .write = proc_uid_map_write,
2721 .read = seq_read,
2722 .llseek = seq_lseek,
2723 .release = proc_id_map_release,
2724};
2725
2726static const struct file_operations proc_gid_map_operations = {
2727 .open = proc_gid_map_open,
2728 .write = proc_gid_map_write,
2729 .read = seq_read,
2730 .llseek = seq_lseek,
2731 .release = proc_id_map_release,
2732};
2733
2734static const struct file_operations proc_projid_map_operations = {
2735 .open = proc_projid_map_open,
2736 .write = proc_projid_map_write,
2737 .read = seq_read,
2738 .llseek = seq_lseek,
2739 .release = proc_id_map_release,
2740};
2741
2742static int proc_setgroups_open(struct inode *inode, struct file *file)
2743{
2744 struct user_namespace *ns = NULL;
2745 struct task_struct *task;
2746 int ret;
2747
2748 ret = -ESRCH;
2749 task = get_proc_task(inode);
2750 if (task) {
2751 rcu_read_lock();
2752 ns = get_user_ns(task_cred_xxx(task, user_ns));
2753 rcu_read_unlock();
2754 put_task_struct(task);
2755 }
2756 if (!ns)
2757 goto err;
2758
2759 if (file->f_mode & FMODE_WRITE) {
2760 ret = -EACCES;
2761 if (!ns_capable(ns, CAP_SYS_ADMIN))
2762 goto err_put_ns;
2763 }
2764
2765 ret = single_open(file, &proc_setgroups_show, ns);
2766 if (ret)
2767 goto err_put_ns;
2768
2769 return 0;
2770err_put_ns:
2771 put_user_ns(ns);
2772err:
2773 return ret;
2774}
2775
2776static int proc_setgroups_release(struct inode *inode, struct file *file)
2777{
2778 struct seq_file *seq = file->private_data;
2779 struct user_namespace *ns = seq->private;
2780 int ret = single_release(inode, file);
2781 put_user_ns(ns);
2782 return ret;
2783}
2784
2785static const struct file_operations proc_setgroups_operations = {
2786 .open = proc_setgroups_open,
2787 .write = proc_setgroups_write,
2788 .read = seq_read,
2789 .llseek = seq_lseek,
2790 .release = proc_setgroups_release,
2791};
2792#endif /* CONFIG_USER_NS */
2793
2794static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2795 struct pid *pid, struct task_struct *task)
2796{
2797 int err = lock_trace(task);
2798 if (!err) {
2799 seq_printf(m, "%08x\n", task->personality);
2800 unlock_trace(task);
2801 }
2802 return err;
2803}
2804
2805/*
2806 * Thread groups
2807 */
2808static const struct file_operations proc_task_operations;
2809static const struct inode_operations proc_task_inode_operations;
2810
2811static const struct pid_entry tgid_base_stuff[] = {
2812 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2813 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2814 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
2815 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2816 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
2817#ifdef CONFIG_NET
2818 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
2819#endif
2820 REG("environ", S_IRUSR, proc_environ_operations),
2821 ONE("auxv", S_IRUSR, proc_pid_auxv),
2822 ONE("status", S_IRUGO, proc_pid_status),
2823 ONE("personality", S_IRUSR, proc_pid_personality),
2824 ONE("limits", S_IRUGO, proc_pid_limits),
2825#ifdef CONFIG_SCHED_DEBUG
2826 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2827#endif
2828#ifdef CONFIG_SCHED_AUTOGROUP
2829 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
2830#endif
2831 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2832#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2833 ONE("syscall", S_IRUSR, proc_pid_syscall),
2834#endif
2835 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
2836 ONE("stat", S_IRUGO, proc_tgid_stat),
2837 ONE("statm", S_IRUGO, proc_pid_statm),
2838 REG("maps", S_IRUGO, proc_pid_maps_operations),
2839#ifdef CONFIG_NUMA
2840 REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
2841#endif
2842 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2843 LNK("cwd", proc_cwd_link),
2844 LNK("root", proc_root_link),
2845 LNK("exe", proc_exe_link),
2846 REG("mounts", S_IRUGO, proc_mounts_operations),
2847 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2848 REG("mountstats", S_IRUSR, proc_mountstats_operations),
2849#ifdef CONFIG_PROC_PAGE_MONITOR
2850 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2851 REG("smaps", S_IRUGO, proc_pid_smaps_operations),
2852 REG("pagemap", S_IRUSR, proc_pagemap_operations),
2853#endif
2854#ifdef CONFIG_SECURITY
2855 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
2856#endif
2857#ifdef CONFIG_KALLSYMS
2858 ONE("wchan", S_IRUGO, proc_pid_wchan),
2859#endif
2860#ifdef CONFIG_STACKTRACE
2861 ONE("stack", S_IRUSR, proc_pid_stack),
2862#endif
2863#ifdef CONFIG_SCHED_INFO
2864 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
2865#endif
2866#ifdef CONFIG_LATENCYTOP
2867 REG("latency", S_IRUGO, proc_lstats_operations),
2868#endif
2869#ifdef CONFIG_PROC_PID_CPUSET
2870 ONE("cpuset", S_IRUGO, proc_cpuset_show),
2871#endif
2872#ifdef CONFIG_CGROUPS
2873 ONE("cgroup", S_IRUGO, proc_cgroup_show),
2874#endif
2875 ONE("oom_score", S_IRUGO, proc_oom_score),
2876 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
2877 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
2878#ifdef CONFIG_AUDITSYSCALL
2879 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2880 REG("sessionid", S_IRUGO, proc_sessionid_operations),
2881#endif
2882#ifdef CONFIG_FAULT_INJECTION
2883 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
2884#endif
2885#ifdef CONFIG_ELF_CORE
2886 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
2887#endif
2888#ifdef CONFIG_TASK_IO_ACCOUNTING
2889 ONE("io", S_IRUSR, proc_tgid_io_accounting),
2890#endif
2891#ifdef CONFIG_HARDWALL
2892 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
2893#endif
2894#ifdef CONFIG_USER_NS
2895 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
2896 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
2897 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
2898 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
2899#endif
2900#ifdef CONFIG_CHECKPOINT_RESTORE
2901 REG("timers", S_IRUGO, proc_timers_operations),
2902#endif
2903 REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
2904};
2905
2906static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx)
2907{
2908 return proc_pident_readdir(file, ctx,
2909 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
2910}
2911
2912static const struct file_operations proc_tgid_base_operations = {
2913 .read = generic_read_dir,
2914 .iterate = proc_tgid_base_readdir,
2915 .llseek = default_llseek,
2916};
2917
2918static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
2919{
2920 return proc_pident_lookup(dir, dentry,
2921 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
2922}
2923
2924static const struct inode_operations proc_tgid_base_inode_operations = {
2925 .lookup = proc_tgid_base_lookup,
2926 .getattr = pid_getattr,
2927 .setattr = proc_setattr,
2928 .permission = proc_pid_permission,
2929};
2930
2931static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
2932{
2933 struct dentry *dentry, *leader, *dir;
2934 char buf[PROC_NUMBUF];
2935 struct qstr name;
2936
2937 name.name = buf;
2938 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2939 /* no ->d_hash() rejects on procfs */
2940 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
2941 if (dentry) {
2942 d_invalidate(dentry);
2943 dput(dentry);
2944 }
2945
2946 if (pid == tgid)
2947 return;
2948
2949 name.name = buf;
2950 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2951 leader = d_hash_and_lookup(mnt->mnt_root, &name);
2952 if (!leader)
2953 goto out;
2954
2955 name.name = "task";
2956 name.len = strlen(name.name);
2957 dir = d_hash_and_lookup(leader, &name);
2958 if (!dir)
2959 goto out_put_leader;
2960
2961 name.name = buf;
2962 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2963 dentry = d_hash_and_lookup(dir, &name);
2964 if (dentry) {
2965 d_invalidate(dentry);
2966 dput(dentry);
2967 }
2968
2969 dput(dir);
2970out_put_leader:
2971 dput(leader);
2972out:
2973 return;
2974}
2975
2976/**
2977 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2978 * @task: task that should be flushed.
2979 *
2980 * When flushing dentries from proc, one needs to flush them from global
2981 * proc (proc_mnt) and from all the namespaces' procs this task was seen
2982 * in. This call is supposed to do all of this job.
2983 *
2984 * Looks in the dcache for
2985 * /proc/@pid
2986 * /proc/@tgid/task/@pid
2987 * if either directory is present flushes it and all of it'ts children
2988 * from the dcache.
2989 *
2990 * It is safe and reasonable to cache /proc entries for a task until
2991 * that task exits. After that they just clog up the dcache with
2992 * useless entries, possibly causing useful dcache entries to be
2993 * flushed instead. This routine is proved to flush those useless
2994 * dcache entries at process exit time.
2995 *
2996 * NOTE: This routine is just an optimization so it does not guarantee
2997 * that no dcache entries will exist at process exit time it
2998 * just makes it very unlikely that any will persist.
2999 */
3000
3001void proc_flush_task(struct task_struct *task)
3002{
3003 int i;
3004 struct pid *pid, *tgid;
3005 struct upid *upid;
3006
3007 pid = task_pid(task);
3008 tgid = task_tgid(task);
3009
3010 for (i = 0; i <= pid->level; i++) {
3011 upid = &pid->numbers[i];
3012 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
3013 tgid->numbers[i].nr);
3014 }
3015}
3016
3017static int proc_pid_instantiate(struct inode *dir,
3018 struct dentry * dentry,
3019 struct task_struct *task, const void *ptr)
3020{
3021 struct inode *inode;
3022
3023 inode = proc_pid_make_inode(dir->i_sb, task);
3024 if (!inode)
3025 goto out;
3026
3027 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3028 inode->i_op = &proc_tgid_base_inode_operations;
3029 inode->i_fop = &proc_tgid_base_operations;
3030 inode->i_flags|=S_IMMUTABLE;
3031
3032 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff,
3033 ARRAY_SIZE(tgid_base_stuff)));
3034
3035 d_set_d_op(dentry, &pid_dentry_operations);
3036
3037 d_add(dentry, inode);
3038 /* Close the race of the process dying before we return the dentry */
3039 if (pid_revalidate(dentry, 0))
3040 return 0;
3041out:
3042 return -ENOENT;
3043}
3044
3045struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3046{
3047 int result = -ENOENT;
3048 struct task_struct *task;
3049 unsigned tgid;
3050 struct pid_namespace *ns;
3051
3052 tgid = name_to_int(&dentry->d_name);
3053 if (tgid == ~0U)
3054 goto out;
3055
3056 ns = dentry->d_sb->s_fs_info;
3057 rcu_read_lock();
3058 task = find_task_by_pid_ns(tgid, ns);
3059 if (task)
3060 get_task_struct(task);
3061 rcu_read_unlock();
3062 if (!task)
3063 goto out;
3064
3065 result = proc_pid_instantiate(dir, dentry, task, NULL);
3066 put_task_struct(task);
3067out:
3068 return ERR_PTR(result);
3069}
3070
3071/*
3072 * Find the first task with tgid >= tgid
3073 *
3074 */
3075struct tgid_iter {
3076 unsigned int tgid;
3077 struct task_struct *task;
3078};
3079static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3080{
3081 struct pid *pid;
3082
3083 if (iter.task)
3084 put_task_struct(iter.task);
3085 rcu_read_lock();
3086retry:
3087 iter.task = NULL;
3088 pid = find_ge_pid(iter.tgid, ns);
3089 if (pid) {
3090 iter.tgid = pid_nr_ns(pid, ns);
3091 iter.task = pid_task(pid, PIDTYPE_PID);
3092 /* What we to know is if the pid we have find is the
3093 * pid of a thread_group_leader. Testing for task
3094 * being a thread_group_leader is the obvious thing
3095 * todo but there is a window when it fails, due to
3096 * the pid transfer logic in de_thread.
3097 *
3098 * So we perform the straight forward test of seeing
3099 * if the pid we have found is the pid of a thread
3100 * group leader, and don't worry if the task we have
3101 * found doesn't happen to be a thread group leader.
3102 * As we don't care in the case of readdir.
3103 */
3104 if (!iter.task || !has_group_leader_pid(iter.task)) {
3105 iter.tgid += 1;
3106 goto retry;
3107 }
3108 get_task_struct(iter.task);
3109 }
3110 rcu_read_unlock();
3111 return iter;
3112}
3113
3114#define TGID_OFFSET (FIRST_PROCESS_ENTRY + 2)
3115
3116/* for the /proc/ directory itself, after non-process stuff has been done */
3117int proc_pid_readdir(struct file *file, struct dir_context *ctx)
3118{
3119 struct tgid_iter iter;
3120 struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info;
3121 loff_t pos = ctx->pos;
3122
3123 if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
3124 return 0;
3125
3126 if (pos == TGID_OFFSET - 2) {
3127 struct inode *inode = d_inode(ns->proc_self);
3128 if (!dir_emit(ctx, "self", 4, inode->i_ino, DT_LNK))
3129 return 0;
3130 ctx->pos = pos = pos + 1;
3131 }
3132 if (pos == TGID_OFFSET - 1) {
3133 struct inode *inode = d_inode(ns->proc_thread_self);
3134 if (!dir_emit(ctx, "thread-self", 11, inode->i_ino, DT_LNK))
3135 return 0;
3136 ctx->pos = pos = pos + 1;
3137 }
3138 iter.tgid = pos - TGID_OFFSET;
3139 iter.task = NULL;
3140 for (iter = next_tgid(ns, iter);
3141 iter.task;
3142 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3143 char name[PROC_NUMBUF];
3144 int len;
3145 if (!has_pid_permissions(ns, iter.task, 2))
3146 continue;
3147
3148 len = snprintf(name, sizeof(name), "%d", iter.tgid);
3149 ctx->pos = iter.tgid + TGID_OFFSET;
3150 if (!proc_fill_cache(file, ctx, name, len,
3151 proc_pid_instantiate, iter.task, NULL)) {
3152 put_task_struct(iter.task);
3153 return 0;
3154 }
3155 }
3156 ctx->pos = PID_MAX_LIMIT + TGID_OFFSET;
3157 return 0;
3158}
3159
3160/*
3161 * Tasks
3162 */
3163static const struct pid_entry tid_base_stuff[] = {
3164 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3165 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3166 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3167#ifdef CONFIG_NET
3168 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
3169#endif
3170 REG("environ", S_IRUSR, proc_environ_operations),
3171 ONE("auxv", S_IRUSR, proc_pid_auxv),
3172 ONE("status", S_IRUGO, proc_pid_status),
3173 ONE("personality", S_IRUSR, proc_pid_personality),
3174 ONE("limits", S_IRUGO, proc_pid_limits),
3175#ifdef CONFIG_SCHED_DEBUG
3176 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3177#endif
3178 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3179#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3180 ONE("syscall", S_IRUSR, proc_pid_syscall),
3181#endif
3182 REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
3183 ONE("stat", S_IRUGO, proc_tid_stat),
3184 ONE("statm", S_IRUGO, proc_pid_statm),
3185 REG("maps", S_IRUGO, proc_tid_maps_operations),
3186#ifdef CONFIG_PROC_CHILDREN
3187 REG("children", S_IRUGO, proc_tid_children_operations),
3188#endif
3189#ifdef CONFIG_NUMA
3190 REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
3191#endif
3192 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3193 LNK("cwd", proc_cwd_link),
3194 LNK("root", proc_root_link),
3195 LNK("exe", proc_exe_link),
3196 REG("mounts", S_IRUGO, proc_mounts_operations),
3197 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3198#ifdef CONFIG_PROC_PAGE_MONITOR
3199 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3200 REG("smaps", S_IRUGO, proc_tid_smaps_operations),
3201 REG("pagemap", S_IRUSR, proc_pagemap_operations),
3202#endif
3203#ifdef CONFIG_SECURITY
3204 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3205#endif
3206#ifdef CONFIG_KALLSYMS
3207 ONE("wchan", S_IRUGO, proc_pid_wchan),
3208#endif
3209#ifdef CONFIG_STACKTRACE
3210 ONE("stack", S_IRUSR, proc_pid_stack),
3211#endif
3212#ifdef CONFIG_SCHED_INFO
3213 ONE("schedstat", S_IRUGO, proc_pid_schedstat),
3214#endif
3215#ifdef CONFIG_LATENCYTOP
3216 REG("latency", S_IRUGO, proc_lstats_operations),
3217#endif
3218#ifdef CONFIG_PROC_PID_CPUSET
3219 ONE("cpuset", S_IRUGO, proc_cpuset_show),
3220#endif
3221#ifdef CONFIG_CGROUPS
3222 ONE("cgroup", S_IRUGO, proc_cgroup_show),
3223#endif
3224 ONE("oom_score", S_IRUGO, proc_oom_score),
3225 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations),
3226 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3227#ifdef CONFIG_AUDITSYSCALL
3228 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3229 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3230#endif
3231#ifdef CONFIG_FAULT_INJECTION
3232 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3233#endif
3234#ifdef CONFIG_TASK_IO_ACCOUNTING
3235 ONE("io", S_IRUSR, proc_tid_io_accounting),
3236#endif
3237#ifdef CONFIG_HARDWALL
3238 ONE("hardwall", S_IRUGO, proc_pid_hardwall),
3239#endif
3240#ifdef CONFIG_USER_NS
3241 REG("uid_map", S_IRUGO|S_IWUSR, proc_uid_map_operations),
3242 REG("gid_map", S_IRUGO|S_IWUSR, proc_gid_map_operations),
3243 REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
3244 REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
3245#endif
3246};
3247
3248static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)
3249{
3250 return proc_pident_readdir(file, ctx,
3251 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3252}
3253
3254static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
3255{
3256 return proc_pident_lookup(dir, dentry,
3257 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3258}
3259
3260static const struct file_operations proc_tid_base_operations = {
3261 .read = generic_read_dir,
3262 .iterate = proc_tid_base_readdir,
3263 .llseek = default_llseek,
3264};
3265
3266static const struct inode_operations proc_tid_base_inode_operations = {
3267 .lookup = proc_tid_base_lookup,
3268 .getattr = pid_getattr,
3269 .setattr = proc_setattr,
3270};
3271
3272static int proc_task_instantiate(struct inode *dir,
3273 struct dentry *dentry, struct task_struct *task, const void *ptr)
3274{
3275 struct inode *inode;
3276 inode = proc_pid_make_inode(dir->i_sb, task);
3277
3278 if (!inode)
3279 goto out;
3280 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3281 inode->i_op = &proc_tid_base_inode_operations;
3282 inode->i_fop = &proc_tid_base_operations;
3283 inode->i_flags|=S_IMMUTABLE;
3284
3285 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff,
3286 ARRAY_SIZE(tid_base_stuff)));
3287
3288 d_set_d_op(dentry, &pid_dentry_operations);
3289
3290 d_add(dentry, inode);
3291 /* Close the race of the process dying before we return the dentry */
3292 if (pid_revalidate(dentry, 0))
3293 return 0;
3294out:
3295 return -ENOENT;
3296}
3297
3298static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
3299{
3300 int result = -ENOENT;
3301 struct task_struct *task;
3302 struct task_struct *leader = get_proc_task(dir);
3303 unsigned tid;
3304 struct pid_namespace *ns;
3305
3306 if (!leader)
3307 goto out_no_task;
3308
3309 tid = name_to_int(&dentry->d_name);
3310 if (tid == ~0U)
3311 goto out;
3312
3313 ns = dentry->d_sb->s_fs_info;
3314 rcu_read_lock();
3315 task = find_task_by_pid_ns(tid, ns);
3316 if (task)
3317 get_task_struct(task);
3318 rcu_read_unlock();
3319 if (!task)
3320 goto out;
3321 if (!same_thread_group(leader, task))
3322 goto out_drop_task;
3323
3324 result = proc_task_instantiate(dir, dentry, task, NULL);
3325out_drop_task:
3326 put_task_struct(task);
3327out:
3328 put_task_struct(leader);
3329out_no_task:
3330 return ERR_PTR(result);
3331}
3332
3333/*
3334 * Find the first tid of a thread group to return to user space.
3335 *
3336 * Usually this is just the thread group leader, but if the users
3337 * buffer was too small or there was a seek into the middle of the
3338 * directory we have more work todo.
3339 *
3340 * In the case of a short read we start with find_task_by_pid.
3341 *
3342 * In the case of a seek we start with the leader and walk nr
3343 * threads past it.
3344 */
3345static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
3346 struct pid_namespace *ns)
3347{
3348 struct task_struct *pos, *task;
3349 unsigned long nr = f_pos;
3350
3351 if (nr != f_pos) /* 32bit overflow? */
3352 return NULL;
3353
3354 rcu_read_lock();
3355 task = pid_task(pid, PIDTYPE_PID);
3356 if (!task)
3357 goto fail;
3358
3359 /* Attempt to start with the tid of a thread */
3360 if (tid && nr) {
3361 pos = find_task_by_pid_ns(tid, ns);
3362 if (pos && same_thread_group(pos, task))
3363 goto found;
3364 }
3365
3366 /* If nr exceeds the number of threads there is nothing todo */
3367 if (nr >= get_nr_threads(task))
3368 goto fail;
3369
3370 /* If we haven't found our starting place yet start
3371 * with the leader and walk nr threads forward.
3372 */
3373 pos = task = task->group_leader;
3374 do {
3375 if (!nr--)
3376 goto found;
3377 } while_each_thread(task, pos);
3378fail:
3379 pos = NULL;
3380 goto out;
3381found:
3382 get_task_struct(pos);
3383out:
3384 rcu_read_unlock();
3385 return pos;
3386}
3387
3388/*
3389 * Find the next thread in the thread list.
3390 * Return NULL if there is an error or no next thread.
3391 *
3392 * The reference to the input task_struct is released.
3393 */
3394static struct task_struct *next_tid(struct task_struct *start)
3395{
3396 struct task_struct *pos = NULL;
3397 rcu_read_lock();
3398 if (pid_alive(start)) {
3399 pos = next_thread(start);
3400 if (thread_group_leader(pos))
3401 pos = NULL;
3402 else
3403 get_task_struct(pos);
3404 }
3405 rcu_read_unlock();
3406 put_task_struct(start);
3407 return pos;
3408}
3409
3410/* for the /proc/TGID/task/ directories */
3411static int proc_task_readdir(struct file *file, struct dir_context *ctx)
3412{
3413 struct inode *inode = file_inode(file);
3414 struct task_struct *task;
3415 struct pid_namespace *ns;
3416 int tid;
3417
3418 if (proc_inode_is_dead(inode))
3419 return -ENOENT;
3420
3421 if (!dir_emit_dots(file, ctx))
3422 return 0;
3423
3424 /* f_version caches the tgid value that the last readdir call couldn't
3425 * return. lseek aka telldir automagically resets f_version to 0.
3426 */
3427 ns = inode->i_sb->s_fs_info;
3428 tid = (int)file->f_version;
3429 file->f_version = 0;
3430 for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);
3431 task;
3432 task = next_tid(task), ctx->pos++) {
3433 char name[PROC_NUMBUF];
3434 int len;
3435 tid = task_pid_nr_ns(task, ns);
3436 len = snprintf(name, sizeof(name), "%d", tid);
3437 if (!proc_fill_cache(file, ctx, name, len,
3438 proc_task_instantiate, task, NULL)) {
3439 /* returning this tgid failed, save it as the first
3440 * pid for the next readir call */
3441 file->f_version = (u64)tid;
3442 put_task_struct(task);
3443 break;
3444 }
3445 }
3446
3447 return 0;
3448}
3449
3450static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3451{
3452 struct inode *inode = d_inode(dentry);
3453 struct task_struct *p = get_proc_task(inode);
3454 generic_fillattr(inode, stat);
3455
3456 if (p) {
3457 stat->nlink += get_nr_threads(p);
3458 put_task_struct(p);
3459 }
3460
3461 return 0;
3462}
3463
3464static const struct inode_operations proc_task_inode_operations = {
3465 .lookup = proc_task_lookup,
3466 .getattr = proc_task_getattr,
3467 .setattr = proc_setattr,
3468 .permission = proc_pid_permission,
3469};
3470
3471static const struct file_operations proc_task_operations = {
3472 .read = generic_read_dir,
3473 .iterate = proc_task_readdir,
3474 .llseek = default_llseek,
3475};