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spi-topcliff-pch: supports a spi mode setup and bit order setup by IO control
[zen-stable.git] / fs / proc / base.c
blobd4548dd49b028fbdc180ef679f20f0952319c4c3
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 #include <linux/flex_array.h>
87 #ifdef CONFIG_HARDWALL
88 #include <asm/hardwall.h>
89 #endif
90 #include <trace/events/oom.h>
91 #include "internal.h"
92
93 /* NOTE:
94 * Implementing inode permission operations in /proc is almost
95 * certainly an error. Permission checks need to happen during
96 * each system call not at open time. The reason is that most of
97 * what we wish to check for permissions in /proc varies at runtime.
98 *
99 * The classic example of a problem is opening file descriptors
100 * in /proc for a task before it execs a suid executable.
101 */
102
103 struct pid_entry {
104 char *name;
105 int len;
106 umode_t mode;
107 const struct inode_operations *iop;
108 const struct file_operations *fop;
109 union proc_op op;
110 };
111
112 #define NOD(NAME, MODE, IOP, FOP, OP) { \
113 .name = (NAME), \
114 .len = sizeof(NAME) - 1, \
115 .mode = MODE, \
116 .iop = IOP, \
117 .fop = FOP, \
118 .op = OP, \
119 }
120
121 #define DIR(NAME, MODE, iops, fops) \
122 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
123 #define LNK(NAME, get_link) \
124 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
125 &proc_pid_link_inode_operations, NULL, \
126 { .proc_get_link = get_link } )
127 #define REG(NAME, MODE, fops) \
128 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
129 #define INF(NAME, MODE, read) \
130 NOD(NAME, (S_IFREG|(MODE)), \
131 NULL, &proc_info_file_operations, \
132 { .proc_read = read } )
133 #define ONE(NAME, MODE, show) \
134 NOD(NAME, (S_IFREG|(MODE)), \
135 NULL, &proc_single_file_operations, \
136 { .proc_show = show } )
137
138 static int proc_fd_permission(struct inode *inode, int mask);
139
140 /*
141 * Count the number of hardlinks for the pid_entry table, excluding the .
142 * and .. links.
143 */
144 static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
145 unsigned int n)
146 {
147 unsigned int i;
148 unsigned int count;
149
150 count = 0;
151 for (i = 0; i < n; ++i) {
152 if (S_ISDIR(entries[i].mode))
153 ++count;
154 }
155
156 return count;
157 }
158
159 static int get_task_root(struct task_struct *task, struct path *root)
160 {
161 int result = -ENOENT;
162
163 task_lock(task);
164 if (task->fs) {
165 get_fs_root(task->fs, root);
166 result = 0;
167 }
168 task_unlock(task);
169 return result;
170 }
171
172 static int proc_cwd_link(struct dentry *dentry, struct path *path)
173 {
174 struct task_struct *task = get_proc_task(dentry->d_inode);
175 int result = -ENOENT;
176
177 if (task) {
178 task_lock(task);
179 if (task->fs) {
180 get_fs_pwd(task->fs, path);
181 result = 0;
182 }
183 task_unlock(task);
184 put_task_struct(task);
185 }
186 return result;
187 }
188
189 static int proc_root_link(struct dentry *dentry, struct path *path)
190 {
191 struct task_struct *task = get_proc_task(dentry->d_inode);
192 int result = -ENOENT;
193
194 if (task) {
195 result = get_task_root(task, path);
196 put_task_struct(task);
197 }
198 return result;
199 }
200
201 struct mm_struct *mm_for_maps(struct task_struct *task)
202 {
203 return mm_access(task, PTRACE_MODE_READ);
204 }
205
206 static int proc_pid_cmdline(struct task_struct *task, char * buffer)
207 {
208 int res = 0;
209 unsigned int len;
210 struct mm_struct *mm = get_task_mm(task);
211 if (!mm)
212 goto out;
213 if (!mm->arg_end)
214 goto out_mm; /* Shh! No looking before we're done */
215
216 len = mm->arg_end - mm->arg_start;
217
218 if (len > PAGE_SIZE)
219 len = PAGE_SIZE;
220
221 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
222
223 // If the nul at the end of args has been overwritten, then
224 // assume application is using setproctitle(3).
225 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
226 len = strnlen(buffer, res);
227 if (len < res) {
228 res = len;
229 } else {
230 len = mm->env_end - mm->env_start;
231 if (len > PAGE_SIZE - res)
232 len = PAGE_SIZE - res;
233 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
234 res = strnlen(buffer, res);
235 }
236 }
237 out_mm:
238 mmput(mm);
239 out:
240 return res;
241 }
242
243 static int proc_pid_auxv(struct task_struct *task, char *buffer)
244 {
245 struct mm_struct *mm = mm_for_maps(task);
246 int res = PTR_ERR(mm);
247 if (mm && !IS_ERR(mm)) {
248 unsigned int nwords = 0;
249 do {
250 nwords += 2;
251 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
252 res = nwords * sizeof(mm->saved_auxv[0]);
253 if (res > PAGE_SIZE)
254 res = PAGE_SIZE;
255 memcpy(buffer, mm->saved_auxv, res);
256 mmput(mm);
257 }
258 return res;
259 }
260
261
262 #ifdef CONFIG_KALLSYMS
263 /*
264 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
265 * Returns the resolved symbol. If that fails, simply return the address.
266 */
267 static int proc_pid_wchan(struct task_struct *task, char *buffer)
268 {
269 unsigned long wchan;
270 char symname[KSYM_NAME_LEN];
271
272 wchan = get_wchan(task);
273
274 if (lookup_symbol_name(wchan, symname) < 0)
275 if (!ptrace_may_access(task, PTRACE_MODE_READ))
276 return 0;
277 else
278 return sprintf(buffer, "%lu", wchan);
279 else
280 return sprintf(buffer, "%s", symname);
281 }
282 #endif /* CONFIG_KALLSYMS */
283
284 static int lock_trace(struct task_struct *task)
285 {
286 int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
287 if (err)
288 return err;
289 if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
290 mutex_unlock(&task->signal->cred_guard_mutex);
291 return -EPERM;
292 }
293 return 0;
294 }
295
296 static void unlock_trace(struct task_struct *task)
297 {
298 mutex_unlock(&task->signal->cred_guard_mutex);
299 }
300
301 #ifdef CONFIG_STACKTRACE
302
303 #define MAX_STACK_TRACE_DEPTH 64
304
305 static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
306 struct pid *pid, struct task_struct *task)
307 {
308 struct stack_trace trace;
309 unsigned long *entries;
310 int err;
311 int i;
312
313 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
314 if (!entries)
315 return -ENOMEM;
316
317 trace.nr_entries = 0;
318 trace.max_entries = MAX_STACK_TRACE_DEPTH;
319 trace.entries = entries;
320 trace.skip = 0;
321
322 err = lock_trace(task);
323 if (!err) {
324 save_stack_trace_tsk(task, &trace);
325
326 for (i = 0; i < trace.nr_entries; i++) {
327 seq_printf(m, "[<%pK>] %pS\n",
328 (void *)entries[i], (void *)entries[i]);
329 }
330 unlock_trace(task);
331 }
332 kfree(entries);
333
334 return err;
335 }
336 #endif
337
338 #ifdef CONFIG_SCHEDSTATS
339 /*
340 * Provides /proc/PID/schedstat
341 */
342 static int proc_pid_schedstat(struct task_struct *task, char *buffer)
343 {
344 return sprintf(buffer, "%llu %llu %lu\n",
345 (unsigned long long)task->se.sum_exec_runtime,
346 (unsigned long long)task->sched_info.run_delay,
347 task->sched_info.pcount);
348 }
349 #endif
350
351 #ifdef CONFIG_LATENCYTOP
352 static int lstats_show_proc(struct seq_file *m, void *v)
353 {
354 int i;
355 struct inode *inode = m->private;
356 struct task_struct *task = get_proc_task(inode);
357
358 if (!task)
359 return -ESRCH;
360 seq_puts(m, "Latency Top version : v0.1\n");
361 for (i = 0; i < 32; i++) {
362 struct latency_record *lr = &task->latency_record[i];
363 if (lr->backtrace[0]) {
364 int q;
365 seq_printf(m, "%i %li %li",
366 lr->count, lr->time, lr->max);
367 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
368 unsigned long bt = lr->backtrace[q];
369 if (!bt)
370 break;
371 if (bt == ULONG_MAX)
372 break;
373 seq_printf(m, " %ps", (void *)bt);
374 }
375 seq_putc(m, '\n');
376 }
377
378 }
379 put_task_struct(task);
380 return 0;
381 }
382
383 static int lstats_open(struct inode *inode, struct file *file)
384 {
385 return single_open(file, lstats_show_proc, inode);
386 }
387
388 static ssize_t lstats_write(struct file *file, const char __user *buf,
389 size_t count, loff_t *offs)
390 {
391 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
392
393 if (!task)
394 return -ESRCH;
395 clear_all_latency_tracing(task);
396 put_task_struct(task);
397
398 return count;
399 }
400
401 static const struct file_operations proc_lstats_operations = {
402 .open = lstats_open,
403 .read = seq_read,
404 .write = lstats_write,
405 .llseek = seq_lseek,
406 .release = single_release,
407 };
408
409 #endif
410
411 static int proc_oom_score(struct task_struct *task, char *buffer)
412 {
413 unsigned long points = 0;
414
415 read_lock(&tasklist_lock);
416 if (pid_alive(task))
417 points = oom_badness(task, NULL, NULL,
418 totalram_pages + total_swap_pages);
419 read_unlock(&tasklist_lock);
420 return sprintf(buffer, "%lu\n", points);
421 }
422
423 struct limit_names {
424 char *name;
425 char *unit;
426 };
427
428 static const struct limit_names lnames[RLIM_NLIMITS] = {
429 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
430 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
431 [RLIMIT_DATA] = {"Max data size", "bytes"},
432 [RLIMIT_STACK] = {"Max stack size", "bytes"},
433 [RLIMIT_CORE] = {"Max core file size", "bytes"},
434 [RLIMIT_RSS] = {"Max resident set", "bytes"},
435 [RLIMIT_NPROC] = {"Max processes", "processes"},
436 [RLIMIT_NOFILE] = {"Max open files", "files"},
437 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
438 [RLIMIT_AS] = {"Max address space", "bytes"},
439 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
440 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
441 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
442 [RLIMIT_NICE] = {"Max nice priority", NULL},
443 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
444 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
445 };
446
447 /* Display limits for a process */
448 static int proc_pid_limits(struct task_struct *task, char *buffer)
449 {
450 unsigned int i;
451 int count = 0;
452 unsigned long flags;
453 char *bufptr = buffer;
454
455 struct rlimit rlim[RLIM_NLIMITS];
456
457 if (!lock_task_sighand(task, &flags))
458 return 0;
459 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
460 unlock_task_sighand(task, &flags);
461
462 /*
463 * print the file header
464 */
465 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
466 "Limit", "Soft Limit", "Hard Limit", "Units");
467
468 for (i = 0; i < RLIM_NLIMITS; i++) {
469 if (rlim[i].rlim_cur == RLIM_INFINITY)
470 count += sprintf(&bufptr[count], "%-25s %-20s ",
471 lnames[i].name, "unlimited");
472 else
473 count += sprintf(&bufptr[count], "%-25s %-20lu ",
474 lnames[i].name, rlim[i].rlim_cur);
475
476 if (rlim[i].rlim_max == RLIM_INFINITY)
477 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
478 else
479 count += sprintf(&bufptr[count], "%-20lu ",
480 rlim[i].rlim_max);
481
482 if (lnames[i].unit)
483 count += sprintf(&bufptr[count], "%-10s\n",
484 lnames[i].unit);
485 else
486 count += sprintf(&bufptr[count], "\n");
487 }
488
489 return count;
490 }
491
492 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
493 static int proc_pid_syscall(struct task_struct *task, char *buffer)
494 {
495 long nr;
496 unsigned long args[6], sp, pc;
497 int res = lock_trace(task);
498 if (res)
499 return res;
500
501 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
502 res = sprintf(buffer, "running\n");
503 else if (nr < 0)
504 res = sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
505 else
506 res = sprintf(buffer,
507 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
508 nr,
509 args[0], args[1], args[2], args[3], args[4], args[5],
510 sp, pc);
511 unlock_trace(task);
512 return res;
513 }
514 #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
515
516 /************************************************************************/
517 /* Here the fs part begins */
518 /************************************************************************/
519
520 /* permission checks */
521 static int proc_fd_access_allowed(struct inode *inode)
522 {
523 struct task_struct *task;
524 int allowed = 0;
525 /* Allow access to a task's file descriptors if it is us or we
526 * may use ptrace attach to the process and find out that
527 * information.
528 */
529 task = get_proc_task(inode);
530 if (task) {
531 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
532 put_task_struct(task);
533 }
534 return allowed;
535 }
536
537 int proc_setattr(struct dentry *dentry, struct iattr *attr)
538 {
539 int error;
540 struct inode *inode = dentry->d_inode;
541
542 if (attr->ia_valid & ATTR_MODE)
543 return -EPERM;
544
545 error = inode_change_ok(inode, attr);
546 if (error)
547 return error;
548
549 if ((attr->ia_valid & ATTR_SIZE) &&
550 attr->ia_size != i_size_read(inode)) {
551 error = vmtruncate(inode, attr->ia_size);
552 if (error)
553 return error;
554 }
555
556 setattr_copy(inode, attr);
557 mark_inode_dirty(inode);
558 return 0;
559 }
560
561 /*
562 * May current process learn task's sched/cmdline info (for hide_pid_min=1)
563 * or euid/egid (for hide_pid_min=2)?
564 */
565 static bool has_pid_permissions(struct pid_namespace *pid,
566 struct task_struct *task,
567 int hide_pid_min)
568 {
569 if (pid->hide_pid < hide_pid_min)
570 return true;
571 if (in_group_p(pid->pid_gid))
572 return true;
573 return ptrace_may_access(task, PTRACE_MODE_READ);
574 }
575
576
577 static int proc_pid_permission(struct inode *inode, int mask)
578 {
579 struct pid_namespace *pid = inode->i_sb->s_fs_info;
580 struct task_struct *task;
581 bool has_perms;
582
583 task = get_proc_task(inode);
584 if (!task)
585 return -ESRCH;
586 has_perms = has_pid_permissions(pid, task, 1);
587 put_task_struct(task);
588
589 if (!has_perms) {
590 if (pid->hide_pid == 2) {
591 /*
592 * Let's make getdents(), stat(), and open()
593 * consistent with each other. If a process
594 * may not stat() a file, it shouldn't be seen
595 * in procfs at all.
596 */
597 return -ENOENT;
598 }
599
600 return -EPERM;
601 }
602 return generic_permission(inode, mask);
603 }
604
605
606
607 static const struct inode_operations proc_def_inode_operations = {
608 .setattr = proc_setattr,
609 };
610
611 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
612
613 static ssize_t proc_info_read(struct file * file, char __user * buf,
614 size_t count, loff_t *ppos)
615 {
616 struct inode * inode = file->f_path.dentry->d_inode;
617 unsigned long page;
618 ssize_t length;
619 struct task_struct *task = get_proc_task(inode);
620
621 length = -ESRCH;
622 if (!task)
623 goto out_no_task;
624
625 if (count > PROC_BLOCK_SIZE)
626 count = PROC_BLOCK_SIZE;
627
628 length = -ENOMEM;
629 if (!(page = __get_free_page(GFP_TEMPORARY)))
630 goto out;
631
632 length = PROC_I(inode)->op.proc_read(task, (char*)page);
633
634 if (length >= 0)
635 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
636 free_page(page);
637 out:
638 put_task_struct(task);
639 out_no_task:
640 return length;
641 }
642
643 static const struct file_operations proc_info_file_operations = {
644 .read = proc_info_read,
645 .llseek = generic_file_llseek,
646 };
647
648 static int proc_single_show(struct seq_file *m, void *v)
649 {
650 struct inode *inode = m->private;
651 struct pid_namespace *ns;
652 struct pid *pid;
653 struct task_struct *task;
654 int ret;
655
656 ns = inode->i_sb->s_fs_info;
657 pid = proc_pid(inode);
658 task = get_pid_task(pid, PIDTYPE_PID);
659 if (!task)
660 return -ESRCH;
661
662 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
663
664 put_task_struct(task);
665 return ret;
666 }
667
668 static int proc_single_open(struct inode *inode, struct file *filp)
669 {
670 return single_open(filp, proc_single_show, inode);
671 }
672
673 static const struct file_operations proc_single_file_operations = {
674 .open = proc_single_open,
675 .read = seq_read,
676 .llseek = seq_lseek,
677 .release = single_release,
678 };
679
680 static int mem_open(struct inode* inode, struct file* file)
681 {
682 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
683 struct mm_struct *mm;
684
685 if (!task)
686 return -ESRCH;
687
688 mm = mm_access(task, PTRACE_MODE_ATTACH);
689 put_task_struct(task);
690
691 if (IS_ERR(mm))
692 return PTR_ERR(mm);
693
694 if (mm) {
695 /* ensure this mm_struct can't be freed */
696 atomic_inc(&mm->mm_count);
697 /* but do not pin its memory */
698 mmput(mm);
699 }
700
701 /* OK to pass negative loff_t, we can catch out-of-range */
702 file->f_mode |= FMODE_UNSIGNED_OFFSET;
703 file->private_data = mm;
704
705 return 0;
706 }
707
708 static ssize_t mem_rw(struct file *file, char __user *buf,
709 size_t count, loff_t *ppos, int write)
710 {
711 struct mm_struct *mm = file->private_data;
712 unsigned long addr = *ppos;
713 ssize_t copied;
714 char *page;
715
716 if (!mm)
717 return 0;
718
719 page = (char *)__get_free_page(GFP_TEMPORARY);
720 if (!page)
721 return -ENOMEM;
722
723 copied = 0;
724 if (!atomic_inc_not_zero(&mm->mm_users))
725 goto free;
726
727 while (count > 0) {
728 int this_len = min_t(int, count, PAGE_SIZE);
729
730 if (write && copy_from_user(page, buf, this_len)) {
731 copied = -EFAULT;
732 break;
733 }
734
735 this_len = access_remote_vm(mm, addr, page, this_len, write);
736 if (!this_len) {
737 if (!copied)
738 copied = -EIO;
739 break;
740 }
741
742 if (!write && copy_to_user(buf, page, this_len)) {
743 copied = -EFAULT;
744 break;
745 }
746
747 buf += this_len;
748 addr += this_len;
749 copied += this_len;
750 count -= this_len;
751 }
752 *ppos = addr;
753
754 mmput(mm);
755 free:
756 free_page((unsigned long) page);
757 return copied;
758 }
759
760 static ssize_t mem_read(struct file *file, char __user *buf,
761 size_t count, loff_t *ppos)
762 {
763 return mem_rw(file, buf, count, ppos, 0);
764 }
765
766 static ssize_t mem_write(struct file *file, const char __user *buf,
767 size_t count, loff_t *ppos)
768 {
769 return mem_rw(file, (char __user*)buf, count, ppos, 1);
770 }
771
772 loff_t mem_lseek(struct file *file, loff_t offset, int orig)
773 {
774 switch (orig) {
775 case 0:
776 file->f_pos = offset;
777 break;
778 case 1:
779 file->f_pos += offset;
780 break;
781 default:
782 return -EINVAL;
783 }
784 force_successful_syscall_return();
785 return file->f_pos;
786 }
787
788 static int mem_release(struct inode *inode, struct file *file)
789 {
790 struct mm_struct *mm = file->private_data;
791 if (mm)
792 mmdrop(mm);
793 return 0;
794 }
795
796 static const struct file_operations proc_mem_operations = {
797 .llseek = mem_lseek,
798 .read = mem_read,
799 .write = mem_write,
800 .open = mem_open,
801 .release = mem_release,
802 };
803
804 static ssize_t environ_read(struct file *file, char __user *buf,
805 size_t count, loff_t *ppos)
806 {
807 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
808 char *page;
809 unsigned long src = *ppos;
810 int ret = -ESRCH;
811 struct mm_struct *mm;
812
813 if (!task)
814 goto out_no_task;
815
816 ret = -ENOMEM;
817 page = (char *)__get_free_page(GFP_TEMPORARY);
818 if (!page)
819 goto out;
820
821
822 mm = mm_for_maps(task);
823 ret = PTR_ERR(mm);
824 if (!mm || IS_ERR(mm))
825 goto out_free;
826
827 ret = 0;
828 while (count > 0) {
829 int this_len, retval, max_len;
830
831 this_len = mm->env_end - (mm->env_start + src);
832
833 if (this_len <= 0)
834 break;
835
836 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
837 this_len = (this_len > max_len) ? max_len : this_len;
838
839 retval = access_process_vm(task, (mm->env_start + src),
840 page, this_len, 0);
841
842 if (retval <= 0) {
843 ret = retval;
844 break;
845 }
846
847 if (copy_to_user(buf, page, retval)) {
848 ret = -EFAULT;
849 break;
850 }
851
852 ret += retval;
853 src += retval;
854 buf += retval;
855 count -= retval;
856 }
857 *ppos = src;
858
859 mmput(mm);
860 out_free:
861 free_page((unsigned long) page);
862 out:
863 put_task_struct(task);
864 out_no_task:
865 return ret;
866 }
867
868 static const struct file_operations proc_environ_operations = {
869 .read = environ_read,
870 .llseek = generic_file_llseek,
871 };
872
873 static ssize_t oom_adjust_read(struct file *file, char __user *buf,
874 size_t count, loff_t *ppos)
875 {
876 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
877 char buffer[PROC_NUMBUF];
878 size_t len;
879 int oom_adjust = OOM_DISABLE;
880 unsigned long flags;
881
882 if (!task)
883 return -ESRCH;
884
885 if (lock_task_sighand(task, &flags)) {
886 oom_adjust = task->signal->oom_adj;
887 unlock_task_sighand(task, &flags);
888 }
889
890 put_task_struct(task);
891
892 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
893
894 return simple_read_from_buffer(buf, count, ppos, buffer, len);
895 }
896
897 static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
898 size_t count, loff_t *ppos)
899 {
900 struct task_struct *task;
901 char buffer[PROC_NUMBUF];
902 int oom_adjust;
903 unsigned long flags;
904 int err;
905
906 memset(buffer, 0, sizeof(buffer));
907 if (count > sizeof(buffer) - 1)
908 count = sizeof(buffer) - 1;
909 if (copy_from_user(buffer, buf, count)) {
910 err = -EFAULT;
911 goto out;
912 }
913
914 err = kstrtoint(strstrip(buffer), 0, &oom_adjust);
915 if (err)
916 goto out;
917 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
918 oom_adjust != OOM_DISABLE) {
919 err = -EINVAL;
920 goto out;
921 }
922
923 task = get_proc_task(file->f_path.dentry->d_inode);
924 if (!task) {
925 err = -ESRCH;
926 goto out;
927 }
928
929 task_lock(task);
930 if (!task->mm) {
931 err = -EINVAL;
932 goto err_task_lock;
933 }
934
935 if (!lock_task_sighand(task, &flags)) {
936 err = -ESRCH;
937 goto err_task_lock;
938 }
939
940 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
941 err = -EACCES;
942 goto err_sighand;
943 }
944
945 /*
946 * Warn that /proc/pid/oom_adj is deprecated, see
947 * Documentation/feature-removal-schedule.txt.
948 */
949 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n",
950 current->comm, task_pid_nr(current), task_pid_nr(task),
951 task_pid_nr(task));
952 task->signal->oom_adj = oom_adjust;
953 /*
954 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
955 * value is always attainable.
956 */
957 if (task->signal->oom_adj == OOM_ADJUST_MAX)
958 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
959 else
960 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
961 -OOM_DISABLE;
962 trace_oom_score_adj_update(task);
963 err_sighand:
964 unlock_task_sighand(task, &flags);
965 err_task_lock:
966 task_unlock(task);
967 put_task_struct(task);
968 out:
969 return err < 0 ? err : count;
970 }
971
972 static const struct file_operations proc_oom_adjust_operations = {
973 .read = oom_adjust_read,
974 .write = oom_adjust_write,
975 .llseek = generic_file_llseek,
976 };
977
978 static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
979 size_t count, loff_t *ppos)
980 {
981 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
982 char buffer[PROC_NUMBUF];
983 int oom_score_adj = OOM_SCORE_ADJ_MIN;
984 unsigned long flags;
985 size_t len;
986
987 if (!task)
988 return -ESRCH;
989 if (lock_task_sighand(task, &flags)) {
990 oom_score_adj = task->signal->oom_score_adj;
991 unlock_task_sighand(task, &flags);
992 }
993 put_task_struct(task);
994 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
995 return simple_read_from_buffer(buf, count, ppos, buffer, len);
996 }
997
998 static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
999 size_t count, loff_t *ppos)
1000 {
1001 struct task_struct *task;
1002 char buffer[PROC_NUMBUF];
1003 unsigned long flags;
1004 int oom_score_adj;
1005 int err;
1006
1007 memset(buffer, 0, sizeof(buffer));
1008 if (count > sizeof(buffer) - 1)
1009 count = sizeof(buffer) - 1;
1010 if (copy_from_user(buffer, buf, count)) {
1011 err = -EFAULT;
1012 goto out;
1013 }
1014
1015 err = kstrtoint(strstrip(buffer), 0, &oom_score_adj);
1016 if (err)
1017 goto out;
1018 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1019 oom_score_adj > OOM_SCORE_ADJ_MAX) {
1020 err = -EINVAL;
1021 goto out;
1022 }
1023
1024 task = get_proc_task(file->f_path.dentry->d_inode);
1025 if (!task) {
1026 err = -ESRCH;
1027 goto out;
1028 }
1029
1030 task_lock(task);
1031 if (!task->mm) {
1032 err = -EINVAL;
1033 goto err_task_lock;
1034 }
1035
1036 if (!lock_task_sighand(task, &flags)) {
1037 err = -ESRCH;
1038 goto err_task_lock;
1039 }
1040
1041 if (oom_score_adj < task->signal->oom_score_adj_min &&
1042 !capable(CAP_SYS_RESOURCE)) {
1043 err = -EACCES;
1044 goto err_sighand;
1045 }
1046
1047 task->signal->oom_score_adj = oom_score_adj;
1048 if (has_capability_noaudit(current, CAP_SYS_RESOURCE))
1049 task->signal->oom_score_adj_min = oom_score_adj;
1050 trace_oom_score_adj_update(task);
1051 /*
1052 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1053 * always attainable.
1054 */
1055 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1056 task->signal->oom_adj = OOM_DISABLE;
1057 else
1058 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1059 OOM_SCORE_ADJ_MAX;
1060 err_sighand:
1061 unlock_task_sighand(task, &flags);
1062 err_task_lock:
1063 task_unlock(task);
1064 put_task_struct(task);
1065 out:
1066 return err < 0 ? err : count;
1067 }
1068
1069 static const struct file_operations proc_oom_score_adj_operations = {
1070 .read = oom_score_adj_read,
1071 .write = oom_score_adj_write,
1072 .llseek = default_llseek,
1073 };
1074
1075 #ifdef CONFIG_AUDITSYSCALL
1076 #define TMPBUFLEN 21
1077 static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1078 size_t count, loff_t *ppos)
1079 {
1080 struct inode * inode = file->f_path.dentry->d_inode;
1081 struct task_struct *task = get_proc_task(inode);
1082 ssize_t length;
1083 char tmpbuf[TMPBUFLEN];
1084
1085 if (!task)
1086 return -ESRCH;
1087 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1088 audit_get_loginuid(task));
1089 put_task_struct(task);
1090 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1091 }
1092
1093 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1094 size_t count, loff_t *ppos)
1095 {
1096 struct inode * inode = file->f_path.dentry->d_inode;
1097 char *page, *tmp;
1098 ssize_t length;
1099 uid_t loginuid;
1100
1101 rcu_read_lock();
1102 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1103 rcu_read_unlock();
1104 return -EPERM;
1105 }
1106 rcu_read_unlock();
1107
1108 if (count >= PAGE_SIZE)
1109 count = PAGE_SIZE - 1;
1110
1111 if (*ppos != 0) {
1112 /* No partial writes. */
1113 return -EINVAL;
1114 }
1115 page = (char*)__get_free_page(GFP_TEMPORARY);
1116 if (!page)
1117 return -ENOMEM;
1118 length = -EFAULT;
1119 if (copy_from_user(page, buf, count))
1120 goto out_free_page;
1121
1122 page[count] = '\0';
1123 loginuid = simple_strtoul(page, &tmp, 10);
1124 if (tmp == page) {
1125 length = -EINVAL;
1126 goto out_free_page;
1127
1128 }
1129 length = audit_set_loginuid(loginuid);
1130 if (likely(length == 0))
1131 length = count;
1132
1133 out_free_page:
1134 free_page((unsigned long) page);
1135 return length;
1136 }
1137
1138 static const struct file_operations proc_loginuid_operations = {
1139 .read = proc_loginuid_read,
1140 .write = proc_loginuid_write,
1141 .llseek = generic_file_llseek,
1142 };
1143
1144 static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1145 size_t count, loff_t *ppos)
1146 {
1147 struct inode * inode = file->f_path.dentry->d_inode;
1148 struct task_struct *task = get_proc_task(inode);
1149 ssize_t length;
1150 char tmpbuf[TMPBUFLEN];
1151
1152 if (!task)
1153 return -ESRCH;
1154 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1155 audit_get_sessionid(task));
1156 put_task_struct(task);
1157 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1158 }
1159
1160 static const struct file_operations proc_sessionid_operations = {
1161 .read = proc_sessionid_read,
1162 .llseek = generic_file_llseek,
1163 };
1164 #endif
1165
1166 #ifdef CONFIG_FAULT_INJECTION
1167 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1168 size_t count, loff_t *ppos)
1169 {
1170 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1171 char buffer[PROC_NUMBUF];
1172 size_t len;
1173 int make_it_fail;
1174
1175 if (!task)
1176 return -ESRCH;
1177 make_it_fail = task->make_it_fail;
1178 put_task_struct(task);
1179
1180 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1181
1182 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1183 }
1184
1185 static ssize_t proc_fault_inject_write(struct file * file,
1186 const char __user * buf, size_t count, loff_t *ppos)
1187 {
1188 struct task_struct *task;
1189 char buffer[PROC_NUMBUF], *end;
1190 int make_it_fail;
1191
1192 if (!capable(CAP_SYS_RESOURCE))
1193 return -EPERM;
1194 memset(buffer, 0, sizeof(buffer));
1195 if (count > sizeof(buffer) - 1)
1196 count = sizeof(buffer) - 1;
1197 if (copy_from_user(buffer, buf, count))
1198 return -EFAULT;
1199 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1200 if (*end)
1201 return -EINVAL;
1202 task = get_proc_task(file->f_dentry->d_inode);
1203 if (!task)
1204 return -ESRCH;
1205 task->make_it_fail = make_it_fail;
1206 put_task_struct(task);
1207
1208 return count;
1209 }
1210
1211 static const struct file_operations proc_fault_inject_operations = {
1212 .read = proc_fault_inject_read,
1213 .write = proc_fault_inject_write,
1214 .llseek = generic_file_llseek,
1215 };
1216 #endif
1217
1218
1219 #ifdef CONFIG_SCHED_DEBUG
1220 /*
1221 * Print out various scheduling related per-task fields:
1222 */
1223 static int sched_show(struct seq_file *m, void *v)
1224 {
1225 struct inode *inode = m->private;
1226 struct task_struct *p;
1227
1228 p = get_proc_task(inode);
1229 if (!p)
1230 return -ESRCH;
1231 proc_sched_show_task(p, m);
1232
1233 put_task_struct(p);
1234
1235 return 0;
1236 }
1237
1238 static ssize_t
1239 sched_write(struct file *file, const char __user *buf,
1240 size_t count, loff_t *offset)
1241 {
1242 struct inode *inode = file->f_path.dentry->d_inode;
1243 struct task_struct *p;
1244
1245 p = get_proc_task(inode);
1246 if (!p)
1247 return -ESRCH;
1248 proc_sched_set_task(p);
1249
1250 put_task_struct(p);
1251
1252 return count;
1253 }
1254
1255 static int sched_open(struct inode *inode, struct file *filp)
1256 {
1257 return single_open(filp, sched_show, inode);
1258 }
1259
1260 static const struct file_operations proc_pid_sched_operations = {
1261 .open = sched_open,
1262 .read = seq_read,
1263 .write = sched_write,
1264 .llseek = seq_lseek,
1265 .release = single_release,
1266 };
1267
1268 #endif
1269
1270 #ifdef CONFIG_SCHED_AUTOGROUP
1271 /*
1272 * Print out autogroup related information:
1273 */
1274 static int sched_autogroup_show(struct seq_file *m, void *v)
1275 {
1276 struct inode *inode = m->private;
1277 struct task_struct *p;
1278
1279 p = get_proc_task(inode);
1280 if (!p)
1281 return -ESRCH;
1282 proc_sched_autogroup_show_task(p, m);
1283
1284 put_task_struct(p);
1285
1286 return 0;
1287 }
1288
1289 static ssize_t
1290 sched_autogroup_write(struct file *file, const char __user *buf,
1291 size_t count, loff_t *offset)
1292 {
1293 struct inode *inode = file->f_path.dentry->d_inode;
1294 struct task_struct *p;
1295 char buffer[PROC_NUMBUF];
1296 int nice;
1297 int err;
1298
1299 memset(buffer, 0, sizeof(buffer));
1300 if (count > sizeof(buffer) - 1)
1301 count = sizeof(buffer) - 1;
1302 if (copy_from_user(buffer, buf, count))
1303 return -EFAULT;
1304
1305 err = kstrtoint(strstrip(buffer), 0, &nice);
1306 if (err < 0)
1307 return err;
1308
1309 p = get_proc_task(inode);
1310 if (!p)
1311 return -ESRCH;
1312
1313 err = nice;
1314 err = proc_sched_autogroup_set_nice(p, &err);
1315 if (err)
1316 count = err;
1317
1318 put_task_struct(p);
1319
1320 return count;
1321 }
1322
1323 static int sched_autogroup_open(struct inode *inode, struct file *filp)
1324 {
1325 int ret;
1326
1327 ret = single_open(filp, sched_autogroup_show, NULL);
1328 if (!ret) {
1329 struct seq_file *m = filp->private_data;
1330
1331 m->private = inode;
1332 }
1333 return ret;
1334 }
1335
1336 static const struct file_operations proc_pid_sched_autogroup_operations = {
1337 .open = sched_autogroup_open,
1338 .read = seq_read,
1339 .write = sched_autogroup_write,
1340 .llseek = seq_lseek,
1341 .release = single_release,
1342 };
1343
1344 #endif /* CONFIG_SCHED_AUTOGROUP */
1345
1346 static ssize_t comm_write(struct file *file, const char __user *buf,
1347 size_t count, loff_t *offset)
1348 {
1349 struct inode *inode = file->f_path.dentry->d_inode;
1350 struct task_struct *p;
1351 char buffer[TASK_COMM_LEN];
1352
1353 memset(buffer, 0, sizeof(buffer));
1354 if (count > sizeof(buffer) - 1)
1355 count = sizeof(buffer) - 1;
1356 if (copy_from_user(buffer, buf, count))
1357 return -EFAULT;
1358
1359 p = get_proc_task(inode);
1360 if (!p)
1361 return -ESRCH;
1362
1363 if (same_thread_group(current, p))
1364 set_task_comm(p, buffer);
1365 else
1366 count = -EINVAL;
1367
1368 put_task_struct(p);
1369
1370 return count;
1371 }
1372
1373 static int comm_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
1382 task_lock(p);
1383 seq_printf(m, "%s\n", p->comm);
1384 task_unlock(p);
1385
1386 put_task_struct(p);
1387
1388 return 0;
1389 }
1390
1391 static int comm_open(struct inode *inode, struct file *filp)
1392 {
1393 return single_open(filp, comm_show, inode);
1394 }
1395
1396 static const struct file_operations proc_pid_set_comm_operations = {
1397 .open = comm_open,
1398 .read = seq_read,
1399 .write = comm_write,
1400 .llseek = seq_lseek,
1401 .release = single_release,
1402 };
1403
1404 static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
1405 {
1406 struct task_struct *task;
1407 struct mm_struct *mm;
1408 struct file *exe_file;
1409
1410 task = get_proc_task(dentry->d_inode);
1411 if (!task)
1412 return -ENOENT;
1413 mm = get_task_mm(task);
1414 put_task_struct(task);
1415 if (!mm)
1416 return -ENOENT;
1417 exe_file = get_mm_exe_file(mm);
1418 mmput(mm);
1419 if (exe_file) {
1420 *exe_path = exe_file->f_path;
1421 path_get(&exe_file->f_path);
1422 fput(exe_file);
1423 return 0;
1424 } else
1425 return -ENOENT;
1426 }
1427
1428 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1429 {
1430 struct inode *inode = dentry->d_inode;
1431 int error = -EACCES;
1432
1433 /* We don't need a base pointer in the /proc filesystem */
1434 path_put(&nd->path);
1435
1436 /* Are we allowed to snoop on the tasks file descriptors? */
1437 if (!proc_fd_access_allowed(inode))
1438 goto out;
1439
1440 error = PROC_I(inode)->op.proc_get_link(dentry, &nd->path);
1441 out:
1442 return ERR_PTR(error);
1443 }
1444
1445 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1446 {
1447 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
1448 char *pathname;
1449 int len;
1450
1451 if (!tmp)
1452 return -ENOMEM;
1453
1454 pathname = d_path(path, tmp, PAGE_SIZE);
1455 len = PTR_ERR(pathname);
1456 if (IS_ERR(pathname))
1457 goto out;
1458 len = tmp + PAGE_SIZE - 1 - pathname;
1459
1460 if (len > buflen)
1461 len = buflen;
1462 if (copy_to_user(buffer, pathname, len))
1463 len = -EFAULT;
1464 out:
1465 free_page((unsigned long)tmp);
1466 return len;
1467 }
1468
1469 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1470 {
1471 int error = -EACCES;
1472 struct inode *inode = dentry->d_inode;
1473 struct path path;
1474
1475 /* Are we allowed to snoop on the tasks file descriptors? */
1476 if (!proc_fd_access_allowed(inode))
1477 goto out;
1478
1479 error = PROC_I(inode)->op.proc_get_link(dentry, &path);
1480 if (error)
1481 goto out;
1482
1483 error = do_proc_readlink(&path, buffer, buflen);
1484 path_put(&path);
1485 out:
1486 return error;
1487 }
1488
1489 static const struct inode_operations proc_pid_link_inode_operations = {
1490 .readlink = proc_pid_readlink,
1491 .follow_link = proc_pid_follow_link,
1492 .setattr = proc_setattr,
1493 };
1494
1495
1496 /* building an inode */
1497
1498 static int task_dumpable(struct task_struct *task)
1499 {
1500 int dumpable = 0;
1501 struct mm_struct *mm;
1502
1503 task_lock(task);
1504 mm = task->mm;
1505 if (mm)
1506 dumpable = get_dumpable(mm);
1507 task_unlock(task);
1508 if(dumpable == 1)
1509 return 1;
1510 return 0;
1511 }
1512
1513 struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
1514 {
1515 struct inode * inode;
1516 struct proc_inode *ei;
1517 const struct cred *cred;
1518
1519 /* We need a new inode */
1520
1521 inode = new_inode(sb);
1522 if (!inode)
1523 goto out;
1524
1525 /* Common stuff */
1526 ei = PROC_I(inode);
1527 inode->i_ino = get_next_ino();
1528 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1529 inode->i_op = &proc_def_inode_operations;
1530
1531 /*
1532 * grab the reference to task.
1533 */
1534 ei->pid = get_task_pid(task, PIDTYPE_PID);
1535 if (!ei->pid)
1536 goto out_unlock;
1537
1538 if (task_dumpable(task)) {
1539 rcu_read_lock();
1540 cred = __task_cred(task);
1541 inode->i_uid = cred->euid;
1542 inode->i_gid = cred->egid;
1543 rcu_read_unlock();
1544 }
1545 security_task_to_inode(task, inode);
1546
1547 out:
1548 return inode;
1549
1550 out_unlock:
1551 iput(inode);
1552 return NULL;
1553 }
1554
1555 int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1556 {
1557 struct inode *inode = dentry->d_inode;
1558 struct task_struct *task;
1559 const struct cred *cred;
1560 struct pid_namespace *pid = dentry->d_sb->s_fs_info;
1561
1562 generic_fillattr(inode, stat);
1563
1564 rcu_read_lock();
1565 stat->uid = 0;
1566 stat->gid = 0;
1567 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1568 if (task) {
1569 if (!has_pid_permissions(pid, task, 2)) {
1570 rcu_read_unlock();
1571 /*
1572 * This doesn't prevent learning whether PID exists,
1573 * it only makes getattr() consistent with readdir().
1574 */
1575 return -ENOENT;
1576 }
1577 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1578 task_dumpable(task)) {
1579 cred = __task_cred(task);
1580 stat->uid = cred->euid;
1581 stat->gid = cred->egid;
1582 }
1583 }
1584 rcu_read_unlock();
1585 return 0;
1586 }
1587
1588 /* dentry stuff */
1589
1590 /*
1591 * Exceptional case: normally we are not allowed to unhash a busy
1592 * directory. In this case, however, we can do it - no aliasing problems
1593 * due to the way we treat inodes.
1594 *
1595 * Rewrite the inode's ownerships here because the owning task may have
1596 * performed a setuid(), etc.
1597 *
1598 * Before the /proc/pid/status file was created the only way to read
1599 * the effective uid of a /process was to stat /proc/pid. Reading
1600 * /proc/pid/status is slow enough that procps and other packages
1601 * kept stating /proc/pid. To keep the rules in /proc simple I have
1602 * made this apply to all per process world readable and executable
1603 * directories.
1604 */
1605 int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1606 {
1607 struct inode *inode;
1608 struct task_struct *task;
1609 const struct cred *cred;
1610
1611 if (nd && nd->flags & LOOKUP_RCU)
1612 return -ECHILD;
1613
1614 inode = dentry->d_inode;
1615 task = get_proc_task(inode);
1616
1617 if (task) {
1618 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1619 task_dumpable(task)) {
1620 rcu_read_lock();
1621 cred = __task_cred(task);
1622 inode->i_uid = cred->euid;
1623 inode->i_gid = cred->egid;
1624 rcu_read_unlock();
1625 } else {
1626 inode->i_uid = 0;
1627 inode->i_gid = 0;
1628 }
1629 inode->i_mode &= ~(S_ISUID | S_ISGID);
1630 security_task_to_inode(task, inode);
1631 put_task_struct(task);
1632 return 1;
1633 }
1634 d_drop(dentry);
1635 return 0;
1636 }
1637
1638 static int pid_delete_dentry(const struct dentry * dentry)
1639 {
1640 /* Is the task we represent dead?
1641 * If so, then don't put the dentry on the lru list,
1642 * kill it immediately.
1643 */
1644 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1645 }
1646
1647 const struct dentry_operations pid_dentry_operations =
1648 {
1649 .d_revalidate = pid_revalidate,
1650 .d_delete = pid_delete_dentry,
1651 };
1652
1653 /* Lookups */
1654
1655 /*
1656 * Fill a directory entry.
1657 *
1658 * If possible create the dcache entry and derive our inode number and
1659 * file type from dcache entry.
1660 *
1661 * Since all of the proc inode numbers are dynamically generated, the inode
1662 * numbers do not exist until the inode is cache. This means creating the
1663 * the dcache entry in readdir is necessary to keep the inode numbers
1664 * reported by readdir in sync with the inode numbers reported
1665 * by stat.
1666 */
1667 int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1668 const char *name, int len,
1669 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1670 {
1671 struct dentry *child, *dir = filp->f_path.dentry;
1672 struct inode *inode;
1673 struct qstr qname;
1674 ino_t ino = 0;
1675 unsigned type = DT_UNKNOWN;
1676
1677 qname.name = name;
1678 qname.len = len;
1679 qname.hash = full_name_hash(name, len);
1680
1681 child = d_lookup(dir, &qname);
1682 if (!child) {
1683 struct dentry *new;
1684 new = d_alloc(dir, &qname);
1685 if (new) {
1686 child = instantiate(dir->d_inode, new, task, ptr);
1687 if (child)
1688 dput(new);
1689 else
1690 child = new;
1691 }
1692 }
1693 if (!child || IS_ERR(child) || !child->d_inode)
1694 goto end_instantiate;
1695 inode = child->d_inode;
1696 if (inode) {
1697 ino = inode->i_ino;
1698 type = inode->i_mode >> 12;
1699 }
1700 dput(child);
1701 end_instantiate:
1702 if (!ino)
1703 ino = find_inode_number(dir, &qname);
1704 if (!ino)
1705 ino = 1;
1706 return filldir(dirent, name, len, filp->f_pos, ino, type);
1707 }
1708
1709 static unsigned name_to_int(struct dentry *dentry)
1710 {
1711 const char *name = dentry->d_name.name;
1712 int len = dentry->d_name.len;
1713 unsigned n = 0;
1714
1715 if (len > 1 && *name == '0')
1716 goto out;
1717 while (len-- > 0) {
1718 unsigned c = *name++ - '0';
1719 if (c > 9)
1720 goto out;
1721 if (n >= (~0U-9)/10)
1722 goto out;
1723 n *= 10;
1724 n += c;
1725 }
1726 return n;
1727 out:
1728 return ~0U;
1729 }
1730
1731 #define PROC_FDINFO_MAX 64
1732
1733 static int proc_fd_info(struct inode *inode, struct path *path, char *info)
1734 {
1735 struct task_struct *task = get_proc_task(inode);
1736 struct files_struct *files = NULL;
1737 struct file *file;
1738 int fd = proc_fd(inode);
1739
1740 if (task) {
1741 files = get_files_struct(task);
1742 put_task_struct(task);
1743 }
1744 if (files) {
1745 /*
1746 * We are not taking a ref to the file structure, so we must
1747 * hold ->file_lock.
1748 */
1749 spin_lock(&files->file_lock);
1750 file = fcheck_files(files, fd);
1751 if (file) {
1752 unsigned int f_flags;
1753 struct fdtable *fdt;
1754
1755 fdt = files_fdtable(files);
1756 f_flags = file->f_flags & ~O_CLOEXEC;
1757 if (FD_ISSET(fd, fdt->close_on_exec))
1758 f_flags |= O_CLOEXEC;
1759
1760 if (path) {
1761 *path = file->f_path;
1762 path_get(&file->f_path);
1763 }
1764 if (info)
1765 snprintf(info, PROC_FDINFO_MAX,
1766 "pos:\t%lli\n"
1767 "flags:\t0%o\n",
1768 (long long) file->f_pos,
1769 f_flags);
1770 spin_unlock(&files->file_lock);
1771 put_files_struct(files);
1772 return 0;
1773 }
1774 spin_unlock(&files->file_lock);
1775 put_files_struct(files);
1776 }
1777 return -ENOENT;
1778 }
1779
1780 static int proc_fd_link(struct dentry *dentry, struct path *path)
1781 {
1782 return proc_fd_info(dentry->d_inode, path, NULL);
1783 }
1784
1785 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1786 {
1787 struct inode *inode;
1788 struct task_struct *task;
1789 int fd;
1790 struct files_struct *files;
1791 const struct cred *cred;
1792
1793 if (nd && nd->flags & LOOKUP_RCU)
1794 return -ECHILD;
1795
1796 inode = dentry->d_inode;
1797 task = get_proc_task(inode);
1798 fd = proc_fd(inode);
1799
1800 if (task) {
1801 files = get_files_struct(task);
1802 if (files) {
1803 rcu_read_lock();
1804 if (fcheck_files(files, fd)) {
1805 rcu_read_unlock();
1806 put_files_struct(files);
1807 if (task_dumpable(task)) {
1808 rcu_read_lock();
1809 cred = __task_cred(task);
1810 inode->i_uid = cred->euid;
1811 inode->i_gid = cred->egid;
1812 rcu_read_unlock();
1813 } else {
1814 inode->i_uid = 0;
1815 inode->i_gid = 0;
1816 }
1817 inode->i_mode &= ~(S_ISUID | S_ISGID);
1818 security_task_to_inode(task, inode);
1819 put_task_struct(task);
1820 return 1;
1821 }
1822 rcu_read_unlock();
1823 put_files_struct(files);
1824 }
1825 put_task_struct(task);
1826 }
1827 d_drop(dentry);
1828 return 0;
1829 }
1830
1831 static const struct dentry_operations tid_fd_dentry_operations =
1832 {
1833 .d_revalidate = tid_fd_revalidate,
1834 .d_delete = pid_delete_dentry,
1835 };
1836
1837 static struct dentry *proc_fd_instantiate(struct inode *dir,
1838 struct dentry *dentry, struct task_struct *task, const void *ptr)
1839 {
1840 unsigned fd = *(const unsigned *)ptr;
1841 struct file *file;
1842 struct files_struct *files;
1843 struct inode *inode;
1844 struct proc_inode *ei;
1845 struct dentry *error = ERR_PTR(-ENOENT);
1846
1847 inode = proc_pid_make_inode(dir->i_sb, task);
1848 if (!inode)
1849 goto out;
1850 ei = PROC_I(inode);
1851 ei->fd = fd;
1852 files = get_files_struct(task);
1853 if (!files)
1854 goto out_iput;
1855 inode->i_mode = S_IFLNK;
1856
1857 /*
1858 * We are not taking a ref to the file structure, so we must
1859 * hold ->file_lock.
1860 */
1861 spin_lock(&files->file_lock);
1862 file = fcheck_files(files, fd);
1863 if (!file)
1864 goto out_unlock;
1865 if (file->f_mode & FMODE_READ)
1866 inode->i_mode |= S_IRUSR | S_IXUSR;
1867 if (file->f_mode & FMODE_WRITE)
1868 inode->i_mode |= S_IWUSR | S_IXUSR;
1869 spin_unlock(&files->file_lock);
1870 put_files_struct(files);
1871
1872 inode->i_op = &proc_pid_link_inode_operations;
1873 inode->i_size = 64;
1874 ei->op.proc_get_link = proc_fd_link;
1875 d_set_d_op(dentry, &tid_fd_dentry_operations);
1876 d_add(dentry, inode);
1877 /* Close the race of the process dying before we return the dentry */
1878 if (tid_fd_revalidate(dentry, NULL))
1879 error = NULL;
1880
1881 out:
1882 return error;
1883 out_unlock:
1884 spin_unlock(&files->file_lock);
1885 put_files_struct(files);
1886 out_iput:
1887 iput(inode);
1888 goto out;
1889 }
1890
1891 static struct dentry *proc_lookupfd_common(struct inode *dir,
1892 struct dentry *dentry,
1893 instantiate_t instantiate)
1894 {
1895 struct task_struct *task = get_proc_task(dir);
1896 unsigned fd = name_to_int(dentry);
1897 struct dentry *result = ERR_PTR(-ENOENT);
1898
1899 if (!task)
1900 goto out_no_task;
1901 if (fd == ~0U)
1902 goto out;
1903
1904 result = instantiate(dir, dentry, task, &fd);
1905 out:
1906 put_task_struct(task);
1907 out_no_task:
1908 return result;
1909 }
1910
1911 static int proc_readfd_common(struct file * filp, void * dirent,
1912 filldir_t filldir, instantiate_t instantiate)
1913 {
1914 struct dentry *dentry = filp->f_path.dentry;
1915 struct inode *inode = dentry->d_inode;
1916 struct task_struct *p = get_proc_task(inode);
1917 unsigned int fd, ino;
1918 int retval;
1919 struct files_struct * files;
1920
1921 retval = -ENOENT;
1922 if (!p)
1923 goto out_no_task;
1924 retval = 0;
1925
1926 fd = filp->f_pos;
1927 switch (fd) {
1928 case 0:
1929 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
1930 goto out;
1931 filp->f_pos++;
1932 case 1:
1933 ino = parent_ino(dentry);
1934 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
1935 goto out;
1936 filp->f_pos++;
1937 default:
1938 files = get_files_struct(p);
1939 if (!files)
1940 goto out;
1941 rcu_read_lock();
1942 for (fd = filp->f_pos-2;
1943 fd < files_fdtable(files)->max_fds;
1944 fd++, filp->f_pos++) {
1945 char name[PROC_NUMBUF];
1946 int len;
1947
1948 if (!fcheck_files(files, fd))
1949 continue;
1950 rcu_read_unlock();
1951
1952 len = snprintf(name, sizeof(name), "%d", fd);
1953 if (proc_fill_cache(filp, dirent, filldir,
1954 name, len, instantiate,
1955 p, &fd) < 0) {
1956 rcu_read_lock();
1957 break;
1958 }
1959 rcu_read_lock();
1960 }
1961 rcu_read_unlock();
1962 put_files_struct(files);
1963 }
1964 out:
1965 put_task_struct(p);
1966 out_no_task:
1967 return retval;
1968 }
1969
1970 static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
1971 struct nameidata *nd)
1972 {
1973 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
1974 }
1975
1976 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
1977 {
1978 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
1979 }
1980
1981 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
1982 size_t len, loff_t *ppos)
1983 {
1984 char tmp[PROC_FDINFO_MAX];
1985 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
1986 if (!err)
1987 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
1988 return err;
1989 }
1990
1991 static const struct file_operations proc_fdinfo_file_operations = {
1992 .open = nonseekable_open,
1993 .read = proc_fdinfo_read,
1994 .llseek = no_llseek,
1995 };
1996
1997 static const struct file_operations proc_fd_operations = {
1998 .read = generic_read_dir,
1999 .readdir = proc_readfd,
2000 .llseek = default_llseek,
2001 };
2002
2003 #ifdef CONFIG_CHECKPOINT_RESTORE
2004
2005 /*
2006 * dname_to_vma_addr - maps a dentry name into two unsigned longs
2007 * which represent vma start and end addresses.
2008 */
2009 static int dname_to_vma_addr(struct dentry *dentry,
2010 unsigned long *start, unsigned long *end)
2011 {
2012 if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
2013 return -EINVAL;
2014
2015 return 0;
2016 }
2017
2018 static int map_files_d_revalidate(struct dentry *dentry, struct nameidata *nd)
2019 {
2020 unsigned long vm_start, vm_end;
2021 bool exact_vma_exists = false;
2022 struct mm_struct *mm = NULL;
2023 struct task_struct *task;
2024 const struct cred *cred;
2025 struct inode *inode;
2026 int status = 0;
2027
2028 if (nd && nd->flags & LOOKUP_RCU)
2029 return -ECHILD;
2030
2031 if (!capable(CAP_SYS_ADMIN)) {
2032 status = -EACCES;
2033 goto out_notask;
2034 }
2035
2036 inode = dentry->d_inode;
2037 task = get_proc_task(inode);
2038 if (!task)
2039 goto out_notask;
2040
2041 if (!ptrace_may_access(task, PTRACE_MODE_READ))
2042 goto out;
2043
2044 mm = get_task_mm(task);
2045 if (!mm)
2046 goto out;
2047
2048 if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
2049 down_read(&mm->mmap_sem);
2050 exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
2051 up_read(&mm->mmap_sem);
2052 }
2053
2054 mmput(mm);
2055
2056 if (exact_vma_exists) {
2057 if (task_dumpable(task)) {
2058 rcu_read_lock();
2059 cred = __task_cred(task);
2060 inode->i_uid = cred->euid;
2061 inode->i_gid = cred->egid;
2062 rcu_read_unlock();
2063 } else {
2064 inode->i_uid = 0;
2065 inode->i_gid = 0;
2066 }
2067 security_task_to_inode(task, inode);
2068 status = 1;
2069 }
2070
2071 out:
2072 put_task_struct(task);
2073
2074 out_notask:
2075 if (status <= 0)
2076 d_drop(dentry);
2077
2078 return status;
2079 }
2080
2081 static const struct dentry_operations tid_map_files_dentry_operations = {
2082 .d_revalidate = map_files_d_revalidate,
2083 .d_delete = pid_delete_dentry,
2084 };
2085
2086 static int proc_map_files_get_link(struct dentry *dentry, struct path *path)
2087 {
2088 unsigned long vm_start, vm_end;
2089 struct vm_area_struct *vma;
2090 struct task_struct *task;
2091 struct mm_struct *mm;
2092 int rc;
2093
2094 rc = -ENOENT;
2095 task = get_proc_task(dentry->d_inode);
2096 if (!task)
2097 goto out;
2098
2099 mm = get_task_mm(task);
2100 put_task_struct(task);
2101 if (!mm)
2102 goto out;
2103
2104 rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
2105 if (rc)
2106 goto out_mmput;
2107
2108 down_read(&mm->mmap_sem);
2109 vma = find_exact_vma(mm, vm_start, vm_end);
2110 if (vma && vma->vm_file) {
2111 *path = vma->vm_file->f_path;
2112 path_get(path);
2113 rc = 0;
2114 }
2115 up_read(&mm->mmap_sem);
2116
2117 out_mmput:
2118 mmput(mm);
2119 out:
2120 return rc;
2121 }
2122
2123 struct map_files_info {
2124 struct file *file;
2125 unsigned long len;
2126 unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
2127 };
2128
2129 static struct dentry *
2130 proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
2131 struct task_struct *task, const void *ptr)
2132 {
2133 const struct file *file = ptr;
2134 struct proc_inode *ei;
2135 struct inode *inode;
2136
2137 if (!file)
2138 return ERR_PTR(-ENOENT);
2139
2140 inode = proc_pid_make_inode(dir->i_sb, task);
2141 if (!inode)
2142 return ERR_PTR(-ENOENT);
2143
2144 ei = PROC_I(inode);
2145 ei->op.proc_get_link = proc_map_files_get_link;
2146
2147 inode->i_op = &proc_pid_link_inode_operations;
2148 inode->i_size = 64;
2149 inode->i_mode = S_IFLNK;
2150
2151 if (file->f_mode & FMODE_READ)
2152 inode->i_mode |= S_IRUSR;
2153 if (file->f_mode & FMODE_WRITE)
2154 inode->i_mode |= S_IWUSR;
2155
2156 d_set_d_op(dentry, &tid_map_files_dentry_operations);
2157 d_add(dentry, inode);
2158
2159 return NULL;
2160 }
2161
2162 static struct dentry *proc_map_files_lookup(struct inode *dir,
2163 struct dentry *dentry, struct nameidata *nd)
2164 {
2165 unsigned long vm_start, vm_end;
2166 struct vm_area_struct *vma;
2167 struct task_struct *task;
2168 struct dentry *result;
2169 struct mm_struct *mm;
2170
2171 result = ERR_PTR(-EACCES);
2172 if (!capable(CAP_SYS_ADMIN))
2173 goto out;
2174
2175 result = ERR_PTR(-ENOENT);
2176 task = get_proc_task(dir);
2177 if (!task)
2178 goto out;
2179
2180 result = ERR_PTR(-EACCES);
2181 if (lock_trace(task))
2182 goto out_put_task;
2183
2184 result = ERR_PTR(-ENOENT);
2185 if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
2186 goto out_unlock;
2187
2188 mm = get_task_mm(task);
2189 if (!mm)
2190 goto out_unlock;
2191
2192 down_read(&mm->mmap_sem);
2193 vma = find_exact_vma(mm, vm_start, vm_end);
2194 if (!vma)
2195 goto out_no_vma;
2196
2197 result = proc_map_files_instantiate(dir, dentry, task, vma->vm_file);
2198
2199 out_no_vma:
2200 up_read(&mm->mmap_sem);
2201 mmput(mm);
2202 out_unlock:
2203 unlock_trace(task);
2204 out_put_task:
2205 put_task_struct(task);
2206 out:
2207 return result;
2208 }
2209
2210 static const struct inode_operations proc_map_files_inode_operations = {
2211 .lookup = proc_map_files_lookup,
2212 .permission = proc_fd_permission,
2213 .setattr = proc_setattr,
2214 };
2215
2216 static int
2217 proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
2218 {
2219 struct dentry *dentry = filp->f_path.dentry;
2220 struct inode *inode = dentry->d_inode;
2221 struct vm_area_struct *vma;
2222 struct task_struct *task;
2223 struct mm_struct *mm;
2224 ino_t ino;
2225 int ret;
2226
2227 ret = -EACCES;
2228 if (!capable(CAP_SYS_ADMIN))
2229 goto out;
2230
2231 ret = -ENOENT;
2232 task = get_proc_task(inode);
2233 if (!task)
2234 goto out;
2235
2236 ret = -EACCES;
2237 if (lock_trace(task))
2238 goto out_put_task;
2239
2240 ret = 0;
2241 switch (filp->f_pos) {
2242 case 0:
2243 ino = inode->i_ino;
2244 if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0)
2245 goto out_unlock;
2246 filp->f_pos++;
2247 case 1:
2248 ino = parent_ino(dentry);
2249 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
2250 goto out_unlock;
2251 filp->f_pos++;
2252 default:
2253 {
2254 unsigned long nr_files, pos, i;
2255 struct flex_array *fa = NULL;
2256 struct map_files_info info;
2257 struct map_files_info *p;
2258
2259 mm = get_task_mm(task);
2260 if (!mm)
2261 goto out_unlock;
2262 down_read(&mm->mmap_sem);
2263
2264 nr_files = 0;
2265
2266 /*
2267 * We need two passes here:
2268 *
2269 * 1) Collect vmas of mapped files with mmap_sem taken
2270 * 2) Release mmap_sem and instantiate entries
2271 *
2272 * otherwise we get lockdep complained, since filldir()
2273 * routine might require mmap_sem taken in might_fault().
2274 */
2275
2276 for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
2277 if (vma->vm_file && ++pos > filp->f_pos)
2278 nr_files++;
2279 }
2280
2281 if (nr_files) {
2282 fa = flex_array_alloc(sizeof(info), nr_files,
2283 GFP_KERNEL);
2284 if (!fa || flex_array_prealloc(fa, 0, nr_files,
2285 GFP_KERNEL)) {
2286 ret = -ENOMEM;
2287 if (fa)
2288 flex_array_free(fa);
2289 up_read(&mm->mmap_sem);
2290 mmput(mm);
2291 goto out_unlock;
2292 }
2293 for (i = 0, vma = mm->mmap, pos = 2; vma;
2294 vma = vma->vm_next) {
2295 if (!vma->vm_file)
2296 continue;
2297 if (++pos <= filp->f_pos)
2298 continue;
2299
2300 get_file(vma->vm_file);
2301 info.file = vma->vm_file;
2302 info.len = snprintf(info.name,
2303 sizeof(info.name), "%lx-%lx",
2304 vma->vm_start, vma->vm_end);
2305 if (flex_array_put(fa, i++, &info, GFP_KERNEL))
2306 BUG();
2307 }
2308 }
2309 up_read(&mm->mmap_sem);
2310
2311 for (i = 0; i < nr_files; i++) {
2312 p = flex_array_get(fa, i);
2313 ret = proc_fill_cache(filp, dirent, filldir,
2314 p->name, p->len,
2315 proc_map_files_instantiate,
2316 task, p->file);
2317 if (ret)
2318 break;
2319 filp->f_pos++;
2320 fput(p->file);
2321 }
2322 for (; i < nr_files; i++) {
2323 /*
2324 * In case of error don't forget
2325 * to put rest of file refs.
2326 */
2327 p = flex_array_get(fa, i);
2328 fput(p->file);
2329 }
2330 if (fa)
2331 flex_array_free(fa);
2332 mmput(mm);
2333 }
2334 }
2335
2336 out_unlock:
2337 unlock_trace(task);
2338 out_put_task:
2339 put_task_struct(task);
2340 out:
2341 return ret;
2342 }
2343
2344 static const struct file_operations proc_map_files_operations = {
2345 .read = generic_read_dir,
2346 .readdir = proc_map_files_readdir,
2347 .llseek = default_llseek,
2348 };
2349
2350 #endif /* CONFIG_CHECKPOINT_RESTORE */
2351
2352 /*
2353 * /proc/pid/fd needs a special permission handler so that a process can still
2354 * access /proc/self/fd after it has executed a setuid().
2355 */
2356 static int proc_fd_permission(struct inode *inode, int mask)
2357 {
2358 int rv = generic_permission(inode, mask);
2359 if (rv == 0)
2360 return 0;
2361 if (task_pid(current) == proc_pid(inode))
2362 rv = 0;
2363 return rv;
2364 }
2365
2366 /*
2367 * proc directories can do almost nothing..
2368 */
2369 static const struct inode_operations proc_fd_inode_operations = {
2370 .lookup = proc_lookupfd,
2371 .permission = proc_fd_permission,
2372 .setattr = proc_setattr,
2373 };
2374
2375 static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2376 struct dentry *dentry, struct task_struct *task, const void *ptr)
2377 {
2378 unsigned fd = *(unsigned *)ptr;
2379 struct inode *inode;
2380 struct proc_inode *ei;
2381 struct dentry *error = ERR_PTR(-ENOENT);
2382
2383 inode = proc_pid_make_inode(dir->i_sb, task);
2384 if (!inode)
2385 goto out;
2386 ei = PROC_I(inode);
2387 ei->fd = fd;
2388 inode->i_mode = S_IFREG | S_IRUSR;
2389 inode->i_fop = &proc_fdinfo_file_operations;
2390 d_set_d_op(dentry, &tid_fd_dentry_operations);
2391 d_add(dentry, inode);
2392 /* Close the race of the process dying before we return the dentry */
2393 if (tid_fd_revalidate(dentry, NULL))
2394 error = NULL;
2395
2396 out:
2397 return error;
2398 }
2399
2400 static struct dentry *proc_lookupfdinfo(struct inode *dir,
2401 struct dentry *dentry,
2402 struct nameidata *nd)
2403 {
2404 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2405 }
2406
2407 static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2408 {
2409 return proc_readfd_common(filp, dirent, filldir,
2410 proc_fdinfo_instantiate);
2411 }
2412
2413 static const struct file_operations proc_fdinfo_operations = {
2414 .read = generic_read_dir,
2415 .readdir = proc_readfdinfo,
2416 .llseek = default_llseek,
2417 };
2418
2419 /*
2420 * proc directories can do almost nothing..
2421 */
2422 static const struct inode_operations proc_fdinfo_inode_operations = {
2423 .lookup = proc_lookupfdinfo,
2424 .setattr = proc_setattr,
2425 };
2426
2427
2428 static struct dentry *proc_pident_instantiate(struct inode *dir,
2429 struct dentry *dentry, struct task_struct *task, const void *ptr)
2430 {
2431 const struct pid_entry *p = ptr;
2432 struct inode *inode;
2433 struct proc_inode *ei;
2434 struct dentry *error = ERR_PTR(-ENOENT);
2435
2436 inode = proc_pid_make_inode(dir->i_sb, task);
2437 if (!inode)
2438 goto out;
2439
2440 ei = PROC_I(inode);
2441 inode->i_mode = p->mode;
2442 if (S_ISDIR(inode->i_mode))
2443 set_nlink(inode, 2); /* Use getattr to fix if necessary */
2444 if (p->iop)
2445 inode->i_op = p->iop;
2446 if (p->fop)
2447 inode->i_fop = p->fop;
2448 ei->op = p->op;
2449 d_set_d_op(dentry, &pid_dentry_operations);
2450 d_add(dentry, inode);
2451 /* Close the race of the process dying before we return the dentry */
2452 if (pid_revalidate(dentry, NULL))
2453 error = NULL;
2454 out:
2455 return error;
2456 }
2457
2458 static struct dentry *proc_pident_lookup(struct inode *dir,
2459 struct dentry *dentry,
2460 const struct pid_entry *ents,
2461 unsigned int nents)
2462 {
2463 struct dentry *error;
2464 struct task_struct *task = get_proc_task(dir);
2465 const struct pid_entry *p, *last;
2466
2467 error = ERR_PTR(-ENOENT);
2468
2469 if (!task)
2470 goto out_no_task;
2471
2472 /*
2473 * Yes, it does not scale. And it should not. Don't add
2474 * new entries into /proc/<tgid>/ without very good reasons.
2475 */
2476 last = &ents[nents - 1];
2477 for (p = ents; p <= last; p++) {
2478 if (p->len != dentry->d_name.len)
2479 continue;
2480 if (!memcmp(dentry->d_name.name, p->name, p->len))
2481 break;
2482 }
2483 if (p > last)
2484 goto out;
2485
2486 error = proc_pident_instantiate(dir, dentry, task, p);
2487 out:
2488 put_task_struct(task);
2489 out_no_task:
2490 return error;
2491 }
2492
2493 static int proc_pident_fill_cache(struct file *filp, void *dirent,
2494 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2495 {
2496 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2497 proc_pident_instantiate, task, p);
2498 }
2499
2500 static int proc_pident_readdir(struct file *filp,
2501 void *dirent, filldir_t filldir,
2502 const struct pid_entry *ents, unsigned int nents)
2503 {
2504 int i;
2505 struct dentry *dentry = filp->f_path.dentry;
2506 struct inode *inode = dentry->d_inode;
2507 struct task_struct *task = get_proc_task(inode);
2508 const struct pid_entry *p, *last;
2509 ino_t ino;
2510 int ret;
2511
2512 ret = -ENOENT;
2513 if (!task)
2514 goto out_no_task;
2515
2516 ret = 0;
2517 i = filp->f_pos;
2518 switch (i) {
2519 case 0:
2520 ino = inode->i_ino;
2521 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2522 goto out;
2523 i++;
2524 filp->f_pos++;
2525 /* fall through */
2526 case 1:
2527 ino = parent_ino(dentry);
2528 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2529 goto out;
2530 i++;
2531 filp->f_pos++;
2532 /* fall through */
2533 default:
2534 i -= 2;
2535 if (i >= nents) {
2536 ret = 1;
2537 goto out;
2538 }
2539 p = ents + i;
2540 last = &ents[nents - 1];
2541 while (p <= last) {
2542 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
2543 goto out;
2544 filp->f_pos++;
2545 p++;
2546 }
2547 }
2548
2549 ret = 1;
2550 out:
2551 put_task_struct(task);
2552 out_no_task:
2553 return ret;
2554 }
2555
2556 #ifdef CONFIG_SECURITY
2557 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2558 size_t count, loff_t *ppos)
2559 {
2560 struct inode * inode = file->f_path.dentry->d_inode;
2561 char *p = NULL;
2562 ssize_t length;
2563 struct task_struct *task = get_proc_task(inode);
2564
2565 if (!task)
2566 return -ESRCH;
2567
2568 length = security_getprocattr(task,
2569 (char*)file->f_path.dentry->d_name.name,
2570 &p);
2571 put_task_struct(task);
2572 if (length > 0)
2573 length = simple_read_from_buffer(buf, count, ppos, p, length);
2574 kfree(p);
2575 return length;
2576 }
2577
2578 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2579 size_t count, loff_t *ppos)
2580 {
2581 struct inode * inode = file->f_path.dentry->d_inode;
2582 char *page;
2583 ssize_t length;
2584 struct task_struct *task = get_proc_task(inode);
2585
2586 length = -ESRCH;
2587 if (!task)
2588 goto out_no_task;
2589 if (count > PAGE_SIZE)
2590 count = PAGE_SIZE;
2591
2592 /* No partial writes. */
2593 length = -EINVAL;
2594 if (*ppos != 0)
2595 goto out;
2596
2597 length = -ENOMEM;
2598 page = (char*)__get_free_page(GFP_TEMPORARY);
2599 if (!page)
2600 goto out;
2601
2602 length = -EFAULT;
2603 if (copy_from_user(page, buf, count))
2604 goto out_free;
2605
2606 /* Guard against adverse ptrace interaction */
2607 length = mutex_lock_interruptible(&task->signal->cred_guard_mutex);
2608 if (length < 0)
2609 goto out_free;
2610
2611 length = security_setprocattr(task,
2612 (char*)file->f_path.dentry->d_name.name,
2613 (void*)page, count);
2614 mutex_unlock(&task->signal->cred_guard_mutex);
2615 out_free:
2616 free_page((unsigned long) page);
2617 out:
2618 put_task_struct(task);
2619 out_no_task:
2620 return length;
2621 }
2622
2623 static const struct file_operations proc_pid_attr_operations = {
2624 .read = proc_pid_attr_read,
2625 .write = proc_pid_attr_write,
2626 .llseek = generic_file_llseek,
2627 };
2628
2629 static const struct pid_entry attr_dir_stuff[] = {
2630 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2631 REG("prev", S_IRUGO, proc_pid_attr_operations),
2632 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2633 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2634 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2635 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2636 };
2637
2638 static int proc_attr_dir_readdir(struct file * filp,
2639 void * dirent, filldir_t filldir)
2640 {
2641 return proc_pident_readdir(filp,dirent,filldir,
2642 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
2643 }
2644
2645 static const struct file_operations proc_attr_dir_operations = {
2646 .read = generic_read_dir,
2647 .readdir = proc_attr_dir_readdir,
2648 .llseek = default_llseek,
2649 };
2650
2651 static struct dentry *proc_attr_dir_lookup(struct inode *dir,
2652 struct dentry *dentry, struct nameidata *nd)
2653 {
2654 return proc_pident_lookup(dir, dentry,
2655 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
2656 }
2657
2658 static const struct inode_operations proc_attr_dir_inode_operations = {
2659 .lookup = proc_attr_dir_lookup,
2660 .getattr = pid_getattr,
2661 .setattr = proc_setattr,
2662 };
2663
2664 #endif
2665
2666 #ifdef CONFIG_ELF_CORE
2667 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2668 size_t count, loff_t *ppos)
2669 {
2670 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2671 struct mm_struct *mm;
2672 char buffer[PROC_NUMBUF];
2673 size_t len;
2674 int ret;
2675
2676 if (!task)
2677 return -ESRCH;
2678
2679 ret = 0;
2680 mm = get_task_mm(task);
2681 if (mm) {
2682 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2683 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2684 MMF_DUMP_FILTER_SHIFT));
2685 mmput(mm);
2686 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2687 }
2688
2689 put_task_struct(task);
2690
2691 return ret;
2692 }
2693
2694 static ssize_t proc_coredump_filter_write(struct file *file,
2695 const char __user *buf,
2696 size_t count,
2697 loff_t *ppos)
2698 {
2699 struct task_struct *task;
2700 struct mm_struct *mm;
2701 char buffer[PROC_NUMBUF], *end;
2702 unsigned int val;
2703 int ret;
2704 int i;
2705 unsigned long mask;
2706
2707 ret = -EFAULT;
2708 memset(buffer, 0, sizeof(buffer));
2709 if (count > sizeof(buffer) - 1)
2710 count = sizeof(buffer) - 1;
2711 if (copy_from_user(buffer, buf, count))
2712 goto out_no_task;
2713
2714 ret = -EINVAL;
2715 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2716 if (*end == '\n')
2717 end++;
2718 if (end - buffer == 0)
2719 goto out_no_task;
2720
2721 ret = -ESRCH;
2722 task = get_proc_task(file->f_dentry->d_inode);
2723 if (!task)
2724 goto out_no_task;
2725
2726 ret = end - buffer;
2727 mm = get_task_mm(task);
2728 if (!mm)
2729 goto out_no_mm;
2730
2731 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2732 if (val & mask)
2733 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2734 else
2735 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2736 }
2737
2738 mmput(mm);
2739 out_no_mm:
2740 put_task_struct(task);
2741 out_no_task:
2742 return ret;
2743 }
2744
2745 static const struct file_operations proc_coredump_filter_operations = {
2746 .read = proc_coredump_filter_read,
2747 .write = proc_coredump_filter_write,
2748 .llseek = generic_file_llseek,
2749 };
2750 #endif
2751
2752 /*
2753 * /proc/self:
2754 */
2755 static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2756 int buflen)
2757 {
2758 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2759 pid_t tgid = task_tgid_nr_ns(current, ns);
2760 char tmp[PROC_NUMBUF];
2761 if (!tgid)
2762 return -ENOENT;
2763 sprintf(tmp, "%d", tgid);
2764 return vfs_readlink(dentry,buffer,buflen,tmp);
2765 }
2766
2767 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2768 {
2769 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2770 pid_t tgid = task_tgid_nr_ns(current, ns);
2771 char *name = ERR_PTR(-ENOENT);
2772 if (tgid) {
2773 name = __getname();
2774 if (!name)
2775 name = ERR_PTR(-ENOMEM);
2776 else
2777 sprintf(name, "%d", tgid);
2778 }
2779 nd_set_link(nd, name);
2780 return NULL;
2781 }
2782
2783 static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2784 void *cookie)
2785 {
2786 char *s = nd_get_link(nd);
2787 if (!IS_ERR(s))
2788 __putname(s);
2789 }
2790
2791 static const struct inode_operations proc_self_inode_operations = {
2792 .readlink = proc_self_readlink,
2793 .follow_link = proc_self_follow_link,
2794 .put_link = proc_self_put_link,
2795 };
2796
2797 /*
2798 * proc base
2799 *
2800 * These are the directory entries in the root directory of /proc
2801 * that properly belong to the /proc filesystem, as they describe
2802 * describe something that is process related.
2803 */
2804 static const struct pid_entry proc_base_stuff[] = {
2805 NOD("self", S_IFLNK|S_IRWXUGO,
2806 &proc_self_inode_operations, NULL, {}),
2807 };
2808
2809 static struct dentry *proc_base_instantiate(struct inode *dir,
2810 struct dentry *dentry, struct task_struct *task, const void *ptr)
2811 {
2812 const struct pid_entry *p = ptr;
2813 struct inode *inode;
2814 struct proc_inode *ei;
2815 struct dentry *error;
2816
2817 /* Allocate the inode */
2818 error = ERR_PTR(-ENOMEM);
2819 inode = new_inode(dir->i_sb);
2820 if (!inode)
2821 goto out;
2822
2823 /* Initialize the inode */
2824 ei = PROC_I(inode);
2825 inode->i_ino = get_next_ino();
2826 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2827
2828 /*
2829 * grab the reference to the task.
2830 */
2831 ei->pid = get_task_pid(task, PIDTYPE_PID);
2832 if (!ei->pid)
2833 goto out_iput;
2834
2835 inode->i_mode = p->mode;
2836 if (S_ISDIR(inode->i_mode))
2837 set_nlink(inode, 2);
2838 if (S_ISLNK(inode->i_mode))
2839 inode->i_size = 64;
2840 if (p->iop)
2841 inode->i_op = p->iop;
2842 if (p->fop)
2843 inode->i_fop = p->fop;
2844 ei->op = p->op;
2845 d_add(dentry, inode);
2846 error = NULL;
2847 out:
2848 return error;
2849 out_iput:
2850 iput(inode);
2851 goto out;
2852 }
2853
2854 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2855 {
2856 struct dentry *error;
2857 struct task_struct *task = get_proc_task(dir);
2858 const struct pid_entry *p, *last;
2859
2860 error = ERR_PTR(-ENOENT);
2861
2862 if (!task)
2863 goto out_no_task;
2864
2865 /* Lookup the directory entry */
2866 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2867 for (p = proc_base_stuff; p <= last; p++) {
2868 if (p->len != dentry->d_name.len)
2869 continue;
2870 if (!memcmp(dentry->d_name.name, p->name, p->len))
2871 break;
2872 }
2873 if (p > last)
2874 goto out;
2875
2876 error = proc_base_instantiate(dir, dentry, task, p);
2877
2878 out:
2879 put_task_struct(task);
2880 out_no_task:
2881 return error;
2882 }
2883
2884 static int proc_base_fill_cache(struct file *filp, void *dirent,
2885 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2886 {
2887 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2888 proc_base_instantiate, task, p);
2889 }
2890
2891 #ifdef CONFIG_TASK_IO_ACCOUNTING
2892 static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2893 {
2894 struct task_io_accounting acct = task->ioac;
2895 unsigned long flags;
2896 int result;
2897
2898 result = mutex_lock_killable(&task->signal->cred_guard_mutex);
2899 if (result)
2900 return result;
2901
2902 if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
2903 result = -EACCES;
2904 goto out_unlock;
2905 }
2906
2907 if (whole && lock_task_sighand(task, &flags)) {
2908 struct task_struct *t = task;
2909
2910 task_io_accounting_add(&acct, &task->signal->ioac);
2911 while_each_thread(task, t)
2912 task_io_accounting_add(&acct, &t->ioac);
2913
2914 unlock_task_sighand(task, &flags);
2915 }
2916 result = sprintf(buffer,
2917 "rchar: %llu\n"
2918 "wchar: %llu\n"
2919 "syscr: %llu\n"
2920 "syscw: %llu\n"
2921 "read_bytes: %llu\n"
2922 "write_bytes: %llu\n"
2923 "cancelled_write_bytes: %llu\n",
2924 (unsigned long long)acct.rchar,
2925 (unsigned long long)acct.wchar,
2926 (unsigned long long)acct.syscr,
2927 (unsigned long long)acct.syscw,
2928 (unsigned long long)acct.read_bytes,
2929 (unsigned long long)acct.write_bytes,
2930 (unsigned long long)acct.cancelled_write_bytes);
2931 out_unlock:
2932 mutex_unlock(&task->signal->cred_guard_mutex);
2933 return result;
2934 }
2935
2936 static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2937 {
2938 return do_io_accounting(task, buffer, 0);
2939 }
2940
2941 static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2942 {
2943 return do_io_accounting(task, buffer, 1);
2944 }
2945 #endif /* CONFIG_TASK_IO_ACCOUNTING */
2946
2947 static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2948 struct pid *pid, struct task_struct *task)
2949 {
2950 int err = lock_trace(task);
2951 if (!err) {
2952 seq_printf(m, "%08x\n", task->personality);
2953 unlock_trace(task);
2954 }
2955 return err;
2956 }
2957
2958 /*
2959 * Thread groups
2960 */
2961 static const struct file_operations proc_task_operations;
2962 static const struct inode_operations proc_task_inode_operations;
2963
2964 static const struct pid_entry tgid_base_stuff[] = {
2965 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2966 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2967 #ifdef CONFIG_CHECKPOINT_RESTORE
2968 DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
2969 #endif
2970 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
2971 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
2972 #ifdef CONFIG_NET
2973 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
2974 #endif
2975 REG("environ", S_IRUSR, proc_environ_operations),
2976 INF("auxv", S_IRUSR, proc_pid_auxv),
2977 ONE("status", S_IRUGO, proc_pid_status),
2978 ONE("personality", S_IRUGO, proc_pid_personality),
2979 INF("limits", S_IRUGO, proc_pid_limits),
2980 #ifdef CONFIG_SCHED_DEBUG
2981 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
2982 #endif
2983 #ifdef CONFIG_SCHED_AUTOGROUP
2984 REG("autogroup", S_IRUGO|S_IWUSR, proc_pid_sched_autogroup_operations),
2985 #endif
2986 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
2987 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
2988 INF("syscall", S_IRUGO, proc_pid_syscall),
2989 #endif
2990 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2991 ONE("stat", S_IRUGO, proc_tgid_stat),
2992 ONE("statm", S_IRUGO, proc_pid_statm),
2993 REG("maps", S_IRUGO, proc_maps_operations),
2994 #ifdef CONFIG_NUMA
2995 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
2996 #endif
2997 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2998 LNK("cwd", proc_cwd_link),
2999 LNK("root", proc_root_link),
3000 LNK("exe", proc_exe_link),
3001 REG("mounts", S_IRUGO, proc_mounts_operations),
3002 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3003 REG("mountstats", S_IRUSR, proc_mountstats_operations),
3004 #ifdef CONFIG_PROC_PAGE_MONITOR
3005 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3006 REG("smaps", S_IRUGO, proc_smaps_operations),
3007 REG("pagemap", S_IRUGO, proc_pagemap_operations),
3008 #endif
3009 #ifdef CONFIG_SECURITY
3010 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3011 #endif
3012 #ifdef CONFIG_KALLSYMS
3013 INF("wchan", S_IRUGO, proc_pid_wchan),
3014 #endif
3015 #ifdef CONFIG_STACKTRACE
3016 ONE("stack", S_IRUGO, proc_pid_stack),
3017 #endif
3018 #ifdef CONFIG_SCHEDSTATS
3019 INF("schedstat", S_IRUGO, proc_pid_schedstat),
3020 #endif
3021 #ifdef CONFIG_LATENCYTOP
3022 REG("latency", S_IRUGO, proc_lstats_operations),
3023 #endif
3024 #ifdef CONFIG_PROC_PID_CPUSET
3025 REG("cpuset", S_IRUGO, proc_cpuset_operations),
3026 #endif
3027 #ifdef CONFIG_CGROUPS
3028 REG("cgroup", S_IRUGO, proc_cgroup_operations),
3029 #endif
3030 INF("oom_score", S_IRUGO, proc_oom_score),
3031 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
3032 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3033 #ifdef CONFIG_AUDITSYSCALL
3034 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3035 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3036 #endif
3037 #ifdef CONFIG_FAULT_INJECTION
3038 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3039 #endif
3040 #ifdef CONFIG_ELF_CORE
3041 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3042 #endif
3043 #ifdef CONFIG_TASK_IO_ACCOUNTING
3044 INF("io", S_IRUSR, proc_tgid_io_accounting),
3045 #endif
3046 #ifdef CONFIG_HARDWALL
3047 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3048 #endif
3049 };
3050
3051 static int proc_tgid_base_readdir(struct file * filp,
3052 void * dirent, filldir_t filldir)
3053 {
3054 return proc_pident_readdir(filp,dirent,filldir,
3055 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
3056 }
3057
3058 static const struct file_operations proc_tgid_base_operations = {
3059 .read = generic_read_dir,
3060 .readdir = proc_tgid_base_readdir,
3061 .llseek = default_llseek,
3062 };
3063
3064 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
3065 return proc_pident_lookup(dir, dentry,
3066 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
3067 }
3068
3069 static const struct inode_operations proc_tgid_base_inode_operations = {
3070 .lookup = proc_tgid_base_lookup,
3071 .getattr = pid_getattr,
3072 .setattr = proc_setattr,
3073 .permission = proc_pid_permission,
3074 };
3075
3076 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
3077 {
3078 struct dentry *dentry, *leader, *dir;
3079 char buf[PROC_NUMBUF];
3080 struct qstr name;
3081
3082 name.name = buf;
3083 name.len = snprintf(buf, sizeof(buf), "%d", pid);
3084 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
3085 if (dentry) {
3086 shrink_dcache_parent(dentry);
3087 d_drop(dentry);
3088 dput(dentry);
3089 }
3090
3091 name.name = buf;
3092 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
3093 leader = d_hash_and_lookup(mnt->mnt_root, &name);
3094 if (!leader)
3095 goto out;
3096
3097 name.name = "task";
3098 name.len = strlen(name.name);
3099 dir = d_hash_and_lookup(leader, &name);
3100 if (!dir)
3101 goto out_put_leader;
3102
3103 name.name = buf;
3104 name.len = snprintf(buf, sizeof(buf), "%d", pid);
3105 dentry = d_hash_and_lookup(dir, &name);
3106 if (dentry) {
3107 shrink_dcache_parent(dentry);
3108 d_drop(dentry);
3109 dput(dentry);
3110 }
3111
3112 dput(dir);
3113 out_put_leader:
3114 dput(leader);
3115 out:
3116 return;
3117 }
3118
3119 /**
3120 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
3121 * @task: task that should be flushed.
3122 *
3123 * When flushing dentries from proc, one needs to flush them from global
3124 * proc (proc_mnt) and from all the namespaces' procs this task was seen
3125 * in. This call is supposed to do all of this job.
3126 *
3127 * Looks in the dcache for
3128 * /proc/@pid
3129 * /proc/@tgid/task/@pid
3130 * if either directory is present flushes it and all of it'ts children
3131 * from the dcache.
3132 *
3133 * It is safe and reasonable to cache /proc entries for a task until
3134 * that task exits. After that they just clog up the dcache with
3135 * useless entries, possibly causing useful dcache entries to be
3136 * flushed instead. This routine is proved to flush those useless
3137 * dcache entries at process exit time.
3138 *
3139 * NOTE: This routine is just an optimization so it does not guarantee
3140 * that no dcache entries will exist at process exit time it
3141 * just makes it very unlikely that any will persist.
3142 */
3143
3144 void proc_flush_task(struct task_struct *task)
3145 {
3146 int i;
3147 struct pid *pid, *tgid;
3148 struct upid *upid;
3149
3150 pid = task_pid(task);
3151 tgid = task_tgid(task);
3152
3153 for (i = 0; i <= pid->level; i++) {
3154 upid = &pid->numbers[i];
3155 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
3156 tgid->numbers[i].nr);
3157 }
3158
3159 upid = &pid->numbers[pid->level];
3160 if (upid->nr == 1)
3161 pid_ns_release_proc(upid->ns);
3162 }
3163
3164 static struct dentry *proc_pid_instantiate(struct inode *dir,
3165 struct dentry * dentry,
3166 struct task_struct *task, const void *ptr)
3167 {
3168 struct dentry *error = ERR_PTR(-ENOENT);
3169 struct inode *inode;
3170
3171 inode = proc_pid_make_inode(dir->i_sb, task);
3172 if (!inode)
3173 goto out;
3174
3175 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3176 inode->i_op = &proc_tgid_base_inode_operations;
3177 inode->i_fop = &proc_tgid_base_operations;
3178 inode->i_flags|=S_IMMUTABLE;
3179
3180 set_nlink(inode, 2 + pid_entry_count_dirs(tgid_base_stuff,
3181 ARRAY_SIZE(tgid_base_stuff)));
3182
3183 d_set_d_op(dentry, &pid_dentry_operations);
3184
3185 d_add(dentry, inode);
3186 /* Close the race of the process dying before we return the dentry */
3187 if (pid_revalidate(dentry, NULL))
3188 error = NULL;
3189 out:
3190 return error;
3191 }
3192
3193 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3194 {
3195 struct dentry *result;
3196 struct task_struct *task;
3197 unsigned tgid;
3198 struct pid_namespace *ns;
3199
3200 result = proc_base_lookup(dir, dentry);
3201 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
3202 goto out;
3203
3204 tgid = name_to_int(dentry);
3205 if (tgid == ~0U)
3206 goto out;
3207
3208 ns = dentry->d_sb->s_fs_info;
3209 rcu_read_lock();
3210 task = find_task_by_pid_ns(tgid, ns);
3211 if (task)
3212 get_task_struct(task);
3213 rcu_read_unlock();
3214 if (!task)
3215 goto out;
3216
3217 result = proc_pid_instantiate(dir, dentry, task, NULL);
3218 put_task_struct(task);
3219 out:
3220 return result;
3221 }
3222
3223 /*
3224 * Find the first task with tgid >= tgid
3225 *
3226 */
3227 struct tgid_iter {
3228 unsigned int tgid;
3229 struct task_struct *task;
3230 };
3231 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
3232 {
3233 struct pid *pid;
3234
3235 if (iter.task)
3236 put_task_struct(iter.task);
3237 rcu_read_lock();
3238 retry:
3239 iter.task = NULL;
3240 pid = find_ge_pid(iter.tgid, ns);
3241 if (pid) {
3242 iter.tgid = pid_nr_ns(pid, ns);
3243 iter.task = pid_task(pid, PIDTYPE_PID);
3244 /* What we to know is if the pid we have find is the
3245 * pid of a thread_group_leader. Testing for task
3246 * being a thread_group_leader is the obvious thing
3247 * todo but there is a window when it fails, due to
3248 * the pid transfer logic in de_thread.
3249 *
3250 * So we perform the straight forward test of seeing
3251 * if the pid we have found is the pid of a thread
3252 * group leader, and don't worry if the task we have
3253 * found doesn't happen to be a thread group leader.
3254 * As we don't care in the case of readdir.
3255 */
3256 if (!iter.task || !has_group_leader_pid(iter.task)) {
3257 iter.tgid += 1;
3258 goto retry;
3259 }
3260 get_task_struct(iter.task);
3261 }
3262 rcu_read_unlock();
3263 return iter;
3264 }
3265
3266 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
3267
3268 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3269 struct tgid_iter iter)
3270 {
3271 char name[PROC_NUMBUF];
3272 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
3273 return proc_fill_cache(filp, dirent, filldir, name, len,
3274 proc_pid_instantiate, iter.task, NULL);
3275 }
3276
3277 static int fake_filldir(void *buf, const char *name, int namelen,
3278 loff_t offset, u64 ino, unsigned d_type)
3279 {
3280 return 0;
3281 }
3282
3283 /* for the /proc/ directory itself, after non-process stuff has been done */
3284 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
3285 {
3286 unsigned int nr;
3287 struct task_struct *reaper;
3288 struct tgid_iter iter;
3289 struct pid_namespace *ns;
3290 filldir_t __filldir;
3291
3292 if (filp->f_pos >= PID_MAX_LIMIT + TGID_OFFSET)
3293 goto out_no_task;
3294 nr = filp->f_pos - FIRST_PROCESS_ENTRY;
3295
3296 reaper = get_proc_task(filp->f_path.dentry->d_inode);
3297 if (!reaper)
3298 goto out_no_task;
3299
3300 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
3301 const struct pid_entry *p = &proc_base_stuff[nr];
3302 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
3303 goto out;
3304 }
3305
3306 ns = filp->f_dentry->d_sb->s_fs_info;
3307 iter.task = NULL;
3308 iter.tgid = filp->f_pos - TGID_OFFSET;
3309 for (iter = next_tgid(ns, iter);
3310 iter.task;
3311 iter.tgid += 1, iter = next_tgid(ns, iter)) {
3312 if (has_pid_permissions(ns, iter.task, 2))
3313 __filldir = filldir;
3314 else
3315 __filldir = fake_filldir;
3316
3317 filp->f_pos = iter.tgid + TGID_OFFSET;
3318 if (proc_pid_fill_cache(filp, dirent, __filldir, iter) < 0) {
3319 put_task_struct(iter.task);
3320 goto out;
3321 }
3322 }
3323 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
3324 out:
3325 put_task_struct(reaper);
3326 out_no_task:
3327 return 0;
3328 }
3329
3330 /*
3331 * Tasks
3332 */
3333 static const struct pid_entry tid_base_stuff[] = {
3334 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3335 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
3336 DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
3337 REG("environ", S_IRUSR, proc_environ_operations),
3338 INF("auxv", S_IRUSR, proc_pid_auxv),
3339 ONE("status", S_IRUGO, proc_pid_status),
3340 ONE("personality", S_IRUGO, proc_pid_personality),
3341 INF("limits", S_IRUGO, proc_pid_limits),
3342 #ifdef CONFIG_SCHED_DEBUG
3343 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
3344 #endif
3345 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
3346 #ifdef CONFIG_HAVE_ARCH_TRACEHOOK
3347 INF("syscall", S_IRUGO, proc_pid_syscall),
3348 #endif
3349 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3350 ONE("stat", S_IRUGO, proc_tid_stat),
3351 ONE("statm", S_IRUGO, proc_pid_statm),
3352 REG("maps", S_IRUGO, proc_maps_operations),
3353 #ifdef CONFIG_NUMA
3354 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
3355 #endif
3356 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3357 LNK("cwd", proc_cwd_link),
3358 LNK("root", proc_root_link),
3359 LNK("exe", proc_exe_link),
3360 REG("mounts", S_IRUGO, proc_mounts_operations),
3361 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
3362 #ifdef CONFIG_PROC_PAGE_MONITOR
3363 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3364 REG("smaps", S_IRUGO, proc_smaps_operations),
3365 REG("pagemap", S_IRUGO, proc_pagemap_operations),
3366 #endif
3367 #ifdef CONFIG_SECURITY
3368 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
3369 #endif
3370 #ifdef CONFIG_KALLSYMS
3371 INF("wchan", S_IRUGO, proc_pid_wchan),
3372 #endif
3373 #ifdef CONFIG_STACKTRACE
3374 ONE("stack", S_IRUGO, proc_pid_stack),
3375 #endif
3376 #ifdef CONFIG_SCHEDSTATS
3377 INF("schedstat", S_IRUGO, proc_pid_schedstat),
3378 #endif
3379 #ifdef CONFIG_LATENCYTOP
3380 REG("latency", S_IRUGO, proc_lstats_operations),
3381 #endif
3382 #ifdef CONFIG_PROC_PID_CPUSET
3383 REG("cpuset", S_IRUGO, proc_cpuset_operations),
3384 #endif
3385 #ifdef CONFIG_CGROUPS
3386 REG("cgroup", S_IRUGO, proc_cgroup_operations),
3387 #endif
3388 INF("oom_score", S_IRUGO, proc_oom_score),
3389 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
3390 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
3391 #ifdef CONFIG_AUDITSYSCALL
3392 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3393 REG("sessionid", S_IRUGO, proc_sessionid_operations),
3394 #endif
3395 #ifdef CONFIG_FAULT_INJECTION
3396 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
3397 #endif
3398 #ifdef CONFIG_TASK_IO_ACCOUNTING
3399 INF("io", S_IRUSR, proc_tid_io_accounting),
3400 #endif
3401 #ifdef CONFIG_HARDWALL
3402 INF("hardwall", S_IRUGO, proc_pid_hardwall),
3403 #endif
3404 };
3405
3406 static int proc_tid_base_readdir(struct file * filp,
3407 void * dirent, filldir_t filldir)
3408 {
3409 return proc_pident_readdir(filp,dirent,filldir,
3410 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3411 }
3412
3413 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
3414 return proc_pident_lookup(dir, dentry,
3415 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
3416 }
3417
3418 static const struct file_operations proc_tid_base_operations = {
3419 .read = generic_read_dir,
3420 .readdir = proc_tid_base_readdir,
3421 .llseek = default_llseek,
3422 };
3423
3424 static const struct inode_operations proc_tid_base_inode_operations = {
3425 .lookup = proc_tid_base_lookup,
3426 .getattr = pid_getattr,
3427 .setattr = proc_setattr,
3428 };
3429
3430 static struct dentry *proc_task_instantiate(struct inode *dir,
3431 struct dentry *dentry, struct task_struct *task, const void *ptr)
3432 {
3433 struct dentry *error = ERR_PTR(-ENOENT);
3434 struct inode *inode;
3435 inode = proc_pid_make_inode(dir->i_sb, task);
3436
3437 if (!inode)
3438 goto out;
3439 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3440 inode->i_op = &proc_tid_base_inode_operations;
3441 inode->i_fop = &proc_tid_base_operations;
3442 inode->i_flags|=S_IMMUTABLE;
3443
3444 set_nlink(inode, 2 + pid_entry_count_dirs(tid_base_stuff,
3445 ARRAY_SIZE(tid_base_stuff)));
3446
3447 d_set_d_op(dentry, &pid_dentry_operations);
3448
3449 d_add(dentry, inode);
3450 /* Close the race of the process dying before we return the dentry */
3451 if (pid_revalidate(dentry, NULL))
3452 error = NULL;
3453 out:
3454 return error;
3455 }
3456
3457 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3458 {
3459 struct dentry *result = ERR_PTR(-ENOENT);
3460 struct task_struct *task;
3461 struct task_struct *leader = get_proc_task(dir);
3462 unsigned tid;
3463 struct pid_namespace *ns;
3464
3465 if (!leader)
3466 goto out_no_task;
3467
3468 tid = name_to_int(dentry);
3469 if (tid == ~0U)
3470 goto out;
3471
3472 ns = dentry->d_sb->s_fs_info;
3473 rcu_read_lock();
3474 task = find_task_by_pid_ns(tid, ns);
3475 if (task)
3476 get_task_struct(task);
3477 rcu_read_unlock();
3478 if (!task)
3479 goto out;
3480 if (!same_thread_group(leader, task))
3481 goto out_drop_task;
3482
3483 result = proc_task_instantiate(dir, dentry, task, NULL);
3484 out_drop_task:
3485 put_task_struct(task);
3486 out:
3487 put_task_struct(leader);
3488 out_no_task:
3489 return result;
3490 }
3491
3492 /*
3493 * Find the first tid of a thread group to return to user space.
3494 *
3495 * Usually this is just the thread group leader, but if the users
3496 * buffer was too small or there was a seek into the middle of the
3497 * directory we have more work todo.
3498 *
3499 * In the case of a short read we start with find_task_by_pid.
3500 *
3501 * In the case of a seek we start with the leader and walk nr
3502 * threads past it.
3503 */
3504 static struct task_struct *first_tid(struct task_struct *leader,
3505 int tid, int nr, struct pid_namespace *ns)
3506 {
3507 struct task_struct *pos;
3508
3509 rcu_read_lock();
3510 /* Attempt to start with the pid of a thread */
3511 if (tid && (nr > 0)) {
3512 pos = find_task_by_pid_ns(tid, ns);
3513 if (pos && (pos->group_leader == leader))
3514 goto found;
3515 }
3516
3517 /* If nr exceeds the number of threads there is nothing todo */
3518 pos = NULL;
3519 if (nr && nr >= get_nr_threads(leader))
3520 goto out;
3521
3522 /* If we haven't found our starting place yet start
3523 * with the leader and walk nr threads forward.
3524 */
3525 for (pos = leader; nr > 0; --nr) {
3526 pos = next_thread(pos);
3527 if (pos == leader) {
3528 pos = NULL;
3529 goto out;
3530 }
3531 }
3532 found:
3533 get_task_struct(pos);
3534 out:
3535 rcu_read_unlock();
3536 return pos;
3537 }
3538
3539 /*
3540 * Find the next thread in the thread list.
3541 * Return NULL if there is an error or no next thread.
3542 *
3543 * The reference to the input task_struct is released.
3544 */
3545 static struct task_struct *next_tid(struct task_struct *start)
3546 {
3547 struct task_struct *pos = NULL;
3548 rcu_read_lock();
3549 if (pid_alive(start)) {
3550 pos = next_thread(start);
3551 if (thread_group_leader(pos))
3552 pos = NULL;
3553 else
3554 get_task_struct(pos);
3555 }
3556 rcu_read_unlock();
3557 put_task_struct(start);
3558 return pos;
3559 }
3560
3561 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3562 struct task_struct *task, int tid)
3563 {
3564 char name[PROC_NUMBUF];
3565 int len = snprintf(name, sizeof(name), "%d", tid);
3566 return proc_fill_cache(filp, dirent, filldir, name, len,
3567 proc_task_instantiate, task, NULL);
3568 }
3569
3570 /* for the /proc/TGID/task/ directories */
3571 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3572 {
3573 struct dentry *dentry = filp->f_path.dentry;
3574 struct inode *inode = dentry->d_inode;
3575 struct task_struct *leader = NULL;
3576 struct task_struct *task;
3577 int retval = -ENOENT;
3578 ino_t ino;
3579 int tid;
3580 struct pid_namespace *ns;
3581
3582 task = get_proc_task(inode);
3583 if (!task)
3584 goto out_no_task;
3585 rcu_read_lock();
3586 if (pid_alive(task)) {
3587 leader = task->group_leader;
3588 get_task_struct(leader);
3589 }
3590 rcu_read_unlock();
3591 put_task_struct(task);
3592 if (!leader)
3593 goto out_no_task;
3594 retval = 0;
3595
3596 switch ((unsigned long)filp->f_pos) {
3597 case 0:
3598 ino = inode->i_ino;
3599 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
3600 goto out;
3601 filp->f_pos++;
3602 /* fall through */
3603 case 1:
3604 ino = parent_ino(dentry);
3605 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
3606 goto out;
3607 filp->f_pos++;
3608 /* fall through */
3609 }
3610
3611 /* f_version caches the tgid value that the last readdir call couldn't
3612 * return. lseek aka telldir automagically resets f_version to 0.
3613 */
3614 ns = filp->f_dentry->d_sb->s_fs_info;
3615 tid = (int)filp->f_version;
3616 filp->f_version = 0;
3617 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
3618 task;
3619 task = next_tid(task), filp->f_pos++) {
3620 tid = task_pid_nr_ns(task, ns);
3621 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
3622 /* returning this tgid failed, save it as the first
3623 * pid for the next readir call */
3624 filp->f_version = (u64)tid;
3625 put_task_struct(task);
3626 break;
3627 }
3628 }
3629 out:
3630 put_task_struct(leader);
3631 out_no_task:
3632 return retval;
3633 }
3634
3635 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3636 {
3637 struct inode *inode = dentry->d_inode;
3638 struct task_struct *p = get_proc_task(inode);
3639 generic_fillattr(inode, stat);
3640
3641 if (p) {
3642 stat->nlink += get_nr_threads(p);
3643 put_task_struct(p);
3644 }
3645
3646 return 0;
3647 }
3648
3649 static const struct inode_operations proc_task_inode_operations = {
3650 .lookup = proc_task_lookup,
3651 .getattr = proc_task_getattr,
3652 .setattr = proc_setattr,
3653 .permission = proc_pid_permission,
3654 };
3655
3656 static const struct file_operations proc_task_operations = {
3657 .read = generic_read_dir,
3658 .readdir = proc_task_readdir,
3659 .llseek = default_llseek,
3660 };