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distcleaned, added images/uImage
[wrt350n-kernel.git] / fs / proc / base.c
blob88f8edf18258ac50681474ffc9542c75de30ecda
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/init.h>
57 #include <linux/capability.h>
58 #include <linux/file.h>
59 #include <linux/string.h>
60 #include <linux/seq_file.h>
61 #include <linux/namei.h>
62 #include <linux/mnt_namespace.h>
63 #include <linux/mm.h>
64 #include <linux/rcupdate.h>
65 #include <linux/kallsyms.h>
66 #include <linux/resource.h>
67 #include <linux/module.h>
68 #include <linux/mount.h>
69 #include <linux/security.h>
70 #include <linux/ptrace.h>
71 #include <linux/cgroup.h>
72 #include <linux/cpuset.h>
73 #include <linux/audit.h>
74 #include <linux/poll.h>
75 #include <linux/nsproxy.h>
76 #include <linux/oom.h>
77 #include <linux/elf.h>
78 #include <linux/pid_namespace.h>
79 #include "internal.h"
80
81 /* NOTE:
82 * Implementing inode permission operations in /proc is almost
83 * certainly an error. Permission checks need to happen during
84 * each system call not at open time. The reason is that most of
85 * what we wish to check for permissions in /proc varies at runtime.
86 *
87 * The classic example of a problem is opening file descriptors
88 * in /proc for a task before it execs a suid executable.
89 */
90
91 struct pid_entry {
92 char *name;
93 int len;
94 mode_t mode;
95 const struct inode_operations *iop;
96 const struct file_operations *fop;
97 union proc_op op;
98 };
99
100 #define NOD(NAME, MODE, IOP, FOP, OP) { \
101 .name = (NAME), \
102 .len = sizeof(NAME) - 1, \
103 .mode = MODE, \
104 .iop = IOP, \
105 .fop = FOP, \
106 .op = OP, \
107 }
108
109 #define DIR(NAME, MODE, OTYPE) \
110 NOD(NAME, (S_IFDIR|(MODE)), \
111 &proc_##OTYPE##_inode_operations, &proc_##OTYPE##_operations, \
112 {} )
113 #define LNK(NAME, OTYPE) \
114 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
115 &proc_pid_link_inode_operations, NULL, \
116 { .proc_get_link = &proc_##OTYPE##_link } )
117 #define REG(NAME, MODE, OTYPE) \
118 NOD(NAME, (S_IFREG|(MODE)), NULL, \
119 &proc_##OTYPE##_operations, {})
120 #define INF(NAME, MODE, OTYPE) \
121 NOD(NAME, (S_IFREG|(MODE)), \
122 NULL, &proc_info_file_operations, \
123 { .proc_read = &proc_##OTYPE } )
124 #define ONE(NAME, MODE, OTYPE) \
125 NOD(NAME, (S_IFREG|(MODE)), \
126 NULL, &proc_single_file_operations, \
127 { .proc_show = &proc_##OTYPE } )
128
129 int maps_protect;
130 EXPORT_SYMBOL(maps_protect);
131
132 static struct fs_struct *get_fs_struct(struct task_struct *task)
133 {
134 struct fs_struct *fs;
135 task_lock(task);
136 fs = task->fs;
137 if(fs)
138 atomic_inc(&fs->count);
139 task_unlock(task);
140 return fs;
141 }
142
143 static int get_nr_threads(struct task_struct *tsk)
144 {
145 /* Must be called with the rcu_read_lock held */
146 unsigned long flags;
147 int count = 0;
148
149 if (lock_task_sighand(tsk, &flags)) {
150 count = atomic_read(&tsk->signal->count);
151 unlock_task_sighand(tsk, &flags);
152 }
153 return count;
154 }
155
156 static int proc_cwd_link(struct inode *inode, struct path *path)
157 {
158 struct task_struct *task = get_proc_task(inode);
159 struct fs_struct *fs = NULL;
160 int result = -ENOENT;
161
162 if (task) {
163 fs = get_fs_struct(task);
164 put_task_struct(task);
165 }
166 if (fs) {
167 read_lock(&fs->lock);
168 *path = fs->pwd;
169 path_get(&fs->pwd);
170 read_unlock(&fs->lock);
171 result = 0;
172 put_fs_struct(fs);
173 }
174 return result;
175 }
176
177 static int proc_root_link(struct inode *inode, struct path *path)
178 {
179 struct task_struct *task = get_proc_task(inode);
180 struct fs_struct *fs = NULL;
181 int result = -ENOENT;
182
183 if (task) {
184 fs = get_fs_struct(task);
185 put_task_struct(task);
186 }
187 if (fs) {
188 read_lock(&fs->lock);
189 *path = fs->root;
190 path_get(&fs->root);
191 read_unlock(&fs->lock);
192 result = 0;
193 put_fs_struct(fs);
194 }
195 return result;
196 }
197
198 #define MAY_PTRACE(task) \
199 (task == current || \
200 (task->parent == current && \
201 (task->ptrace & PT_PTRACED) && \
202 (task_is_stopped_or_traced(task)) && \
203 security_ptrace(current,task) == 0))
204
205 struct mm_struct *mm_for_maps(struct task_struct *task)
206 {
207 struct mm_struct *mm = get_task_mm(task);
208 if (!mm)
209 return NULL;
210 down_read(&mm->mmap_sem);
211 task_lock(task);
212 if (task->mm != mm)
213 goto out;
214 if (task->mm != current->mm && __ptrace_may_attach(task) < 0)
215 goto out;
216 task_unlock(task);
217 return mm;
218 out:
219 task_unlock(task);
220 up_read(&mm->mmap_sem);
221 mmput(mm);
222 return NULL;
223 }
224
225 static int proc_pid_cmdline(struct task_struct *task, char * buffer)
226 {
227 int res = 0;
228 unsigned int len;
229 struct mm_struct *mm = get_task_mm(task);
230 if (!mm)
231 goto out;
232 if (!mm->arg_end)
233 goto out_mm; /* Shh! No looking before we're done */
234
235 len = mm->arg_end - mm->arg_start;
236
237 if (len > PAGE_SIZE)
238 len = PAGE_SIZE;
239
240 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
241
242 // If the nul at the end of args has been overwritten, then
243 // assume application is using setproctitle(3).
244 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
245 len = strnlen(buffer, res);
246 if (len < res) {
247 res = len;
248 } else {
249 len = mm->env_end - mm->env_start;
250 if (len > PAGE_SIZE - res)
251 len = PAGE_SIZE - res;
252 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
253 res = strnlen(buffer, res);
254 }
255 }
256 out_mm:
257 mmput(mm);
258 out:
259 return res;
260 }
261
262 static int proc_pid_auxv(struct task_struct *task, char *buffer)
263 {
264 int res = 0;
265 struct mm_struct *mm = get_task_mm(task);
266 if (mm) {
267 unsigned int nwords = 0;
268 do
269 nwords += 2;
270 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
271 res = nwords * sizeof(mm->saved_auxv[0]);
272 if (res > PAGE_SIZE)
273 res = PAGE_SIZE;
274 memcpy(buffer, mm->saved_auxv, res);
275 mmput(mm);
276 }
277 return res;
278 }
279
280
281 #ifdef CONFIG_KALLSYMS
282 /*
283 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
284 * Returns the resolved symbol. If that fails, simply return the address.
285 */
286 static int proc_pid_wchan(struct task_struct *task, char *buffer)
287 {
288 unsigned long wchan;
289 char symname[KSYM_NAME_LEN];
290
291 wchan = get_wchan(task);
292
293 if (lookup_symbol_name(wchan, symname) < 0)
294 return sprintf(buffer, "%lu", wchan);
295 else
296 return sprintf(buffer, "%s", symname);
297 }
298 #endif /* CONFIG_KALLSYMS */
299
300 #ifdef CONFIG_SCHEDSTATS
301 /*
302 * Provides /proc/PID/schedstat
303 */
304 static int proc_pid_schedstat(struct task_struct *task, char *buffer)
305 {
306 return sprintf(buffer, "%llu %llu %lu\n",
307 task->sched_info.cpu_time,
308 task->sched_info.run_delay,
309 task->sched_info.pcount);
310 }
311 #endif
312
313 #ifdef CONFIG_LATENCYTOP
314 static int lstats_show_proc(struct seq_file *m, void *v)
315 {
316 int i;
317 struct task_struct *task = m->private;
318 seq_puts(m, "Latency Top version : v0.1\n");
319
320 for (i = 0; i < 32; i++) {
321 if (task->latency_record[i].backtrace[0]) {
322 int q;
323 seq_printf(m, "%i %li %li ",
324 task->latency_record[i].count,
325 task->latency_record[i].time,
326 task->latency_record[i].max);
327 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
328 char sym[KSYM_NAME_LEN];
329 char *c;
330 if (!task->latency_record[i].backtrace[q])
331 break;
332 if (task->latency_record[i].backtrace[q] == ULONG_MAX)
333 break;
334 sprint_symbol(sym, task->latency_record[i].backtrace[q]);
335 c = strchr(sym, '+');
336 if (c)
337 *c = 0;
338 seq_printf(m, "%s ", sym);
339 }
340 seq_printf(m, "\n");
341 }
342
343 }
344 return 0;
345 }
346
347 static int lstats_open(struct inode *inode, struct file *file)
348 {
349 int ret;
350 struct seq_file *m;
351 struct task_struct *task = get_proc_task(inode);
352
353 ret = single_open(file, lstats_show_proc, NULL);
354 if (!ret) {
355 m = file->private_data;
356 m->private = task;
357 }
358 return ret;
359 }
360
361 static ssize_t lstats_write(struct file *file, const char __user *buf,
362 size_t count, loff_t *offs)
363 {
364 struct seq_file *m;
365 struct task_struct *task;
366
367 m = file->private_data;
368 task = m->private;
369 clear_all_latency_tracing(task);
370
371 return count;
372 }
373
374 static const struct file_operations proc_lstats_operations = {
375 .open = lstats_open,
376 .read = seq_read,
377 .write = lstats_write,
378 .llseek = seq_lseek,
379 .release = single_release,
380 };
381
382 #endif
383
384 /* The badness from the OOM killer */
385 unsigned long badness(struct task_struct *p, unsigned long uptime);
386 static int proc_oom_score(struct task_struct *task, char *buffer)
387 {
388 unsigned long points;
389 struct timespec uptime;
390
391 do_posix_clock_monotonic_gettime(&uptime);
392 read_lock(&tasklist_lock);
393 points = badness(task, uptime.tv_sec);
394 read_unlock(&tasklist_lock);
395 return sprintf(buffer, "%lu\n", points);
396 }
397
398 struct limit_names {
399 char *name;
400 char *unit;
401 };
402
403 static const struct limit_names lnames[RLIM_NLIMITS] = {
404 [RLIMIT_CPU] = {"Max cpu time", "ms"},
405 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
406 [RLIMIT_DATA] = {"Max data size", "bytes"},
407 [RLIMIT_STACK] = {"Max stack size", "bytes"},
408 [RLIMIT_CORE] = {"Max core file size", "bytes"},
409 [RLIMIT_RSS] = {"Max resident set", "bytes"},
410 [RLIMIT_NPROC] = {"Max processes", "processes"},
411 [RLIMIT_NOFILE] = {"Max open files", "files"},
412 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
413 [RLIMIT_AS] = {"Max address space", "bytes"},
414 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
415 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
416 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
417 [RLIMIT_NICE] = {"Max nice priority", NULL},
418 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
419 };
420
421 /* Display limits for a process */
422 static int proc_pid_limits(struct task_struct *task, char *buffer)
423 {
424 unsigned int i;
425 int count = 0;
426 unsigned long flags;
427 char *bufptr = buffer;
428
429 struct rlimit rlim[RLIM_NLIMITS];
430
431 rcu_read_lock();
432 if (!lock_task_sighand(task,&flags)) {
433 rcu_read_unlock();
434 return 0;
435 }
436 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
437 unlock_task_sighand(task, &flags);
438 rcu_read_unlock();
439
440 /*
441 * print the file header
442 */
443 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
444 "Limit", "Soft Limit", "Hard Limit", "Units");
445
446 for (i = 0; i < RLIM_NLIMITS; i++) {
447 if (rlim[i].rlim_cur == RLIM_INFINITY)
448 count += sprintf(&bufptr[count], "%-25s %-20s ",
449 lnames[i].name, "unlimited");
450 else
451 count += sprintf(&bufptr[count], "%-25s %-20lu ",
452 lnames[i].name, rlim[i].rlim_cur);
453
454 if (rlim[i].rlim_max == RLIM_INFINITY)
455 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
456 else
457 count += sprintf(&bufptr[count], "%-20lu ",
458 rlim[i].rlim_max);
459
460 if (lnames[i].unit)
461 count += sprintf(&bufptr[count], "%-10s\n",
462 lnames[i].unit);
463 else
464 count += sprintf(&bufptr[count], "\n");
465 }
466
467 return count;
468 }
469
470 /************************************************************************/
471 /* Here the fs part begins */
472 /************************************************************************/
473
474 /* permission checks */
475 static int proc_fd_access_allowed(struct inode *inode)
476 {
477 struct task_struct *task;
478 int allowed = 0;
479 /* Allow access to a task's file descriptors if it is us or we
480 * may use ptrace attach to the process and find out that
481 * information.
482 */
483 task = get_proc_task(inode);
484 if (task) {
485 allowed = ptrace_may_attach(task);
486 put_task_struct(task);
487 }
488 return allowed;
489 }
490
491 static int proc_setattr(struct dentry *dentry, struct iattr *attr)
492 {
493 int error;
494 struct inode *inode = dentry->d_inode;
495
496 if (attr->ia_valid & ATTR_MODE)
497 return -EPERM;
498
499 error = inode_change_ok(inode, attr);
500 if (!error)
501 error = inode_setattr(inode, attr);
502 return error;
503 }
504
505 static const struct inode_operations proc_def_inode_operations = {
506 .setattr = proc_setattr,
507 };
508
509 extern const struct seq_operations mounts_op;
510 struct proc_mounts {
511 struct seq_file m;
512 int event;
513 };
514
515 static int mounts_open(struct inode *inode, struct file *file)
516 {
517 struct task_struct *task = get_proc_task(inode);
518 struct nsproxy *nsp;
519 struct mnt_namespace *ns = NULL;
520 struct proc_mounts *p;
521 int ret = -EINVAL;
522
523 if (task) {
524 rcu_read_lock();
525 nsp = task_nsproxy(task);
526 if (nsp) {
527 ns = nsp->mnt_ns;
528 if (ns)
529 get_mnt_ns(ns);
530 }
531 rcu_read_unlock();
532
533 put_task_struct(task);
534 }
535
536 if (ns) {
537 ret = -ENOMEM;
538 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
539 if (p) {
540 file->private_data = &p->m;
541 ret = seq_open(file, &mounts_op);
542 if (!ret) {
543 p->m.private = ns;
544 p->event = ns->event;
545 return 0;
546 }
547 kfree(p);
548 }
549 put_mnt_ns(ns);
550 }
551 return ret;
552 }
553
554 static int mounts_release(struct inode *inode, struct file *file)
555 {
556 struct seq_file *m = file->private_data;
557 struct mnt_namespace *ns = m->private;
558 put_mnt_ns(ns);
559 return seq_release(inode, file);
560 }
561
562 static unsigned mounts_poll(struct file *file, poll_table *wait)
563 {
564 struct proc_mounts *p = file->private_data;
565 struct mnt_namespace *ns = p->m.private;
566 unsigned res = 0;
567
568 poll_wait(file, &ns->poll, wait);
569
570 spin_lock(&vfsmount_lock);
571 if (p->event != ns->event) {
572 p->event = ns->event;
573 res = POLLERR;
574 }
575 spin_unlock(&vfsmount_lock);
576
577 return res;
578 }
579
580 static const struct file_operations proc_mounts_operations = {
581 .open = mounts_open,
582 .read = seq_read,
583 .llseek = seq_lseek,
584 .release = mounts_release,
585 .poll = mounts_poll,
586 };
587
588 extern const struct seq_operations mountstats_op;
589 static int mountstats_open(struct inode *inode, struct file *file)
590 {
591 int ret = seq_open(file, &mountstats_op);
592
593 if (!ret) {
594 struct seq_file *m = file->private_data;
595 struct nsproxy *nsp;
596 struct mnt_namespace *mnt_ns = NULL;
597 struct task_struct *task = get_proc_task(inode);
598
599 if (task) {
600 rcu_read_lock();
601 nsp = task_nsproxy(task);
602 if (nsp) {
603 mnt_ns = nsp->mnt_ns;
604 if (mnt_ns)
605 get_mnt_ns(mnt_ns);
606 }
607 rcu_read_unlock();
608
609 put_task_struct(task);
610 }
611
612 if (mnt_ns)
613 m->private = mnt_ns;
614 else {
615 seq_release(inode, file);
616 ret = -EINVAL;
617 }
618 }
619 return ret;
620 }
621
622 static const struct file_operations proc_mountstats_operations = {
623 .open = mountstats_open,
624 .read = seq_read,
625 .llseek = seq_lseek,
626 .release = mounts_release,
627 };
628
629 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
630
631 static ssize_t proc_info_read(struct file * file, char __user * buf,
632 size_t count, loff_t *ppos)
633 {
634 struct inode * inode = file->f_path.dentry->d_inode;
635 unsigned long page;
636 ssize_t length;
637 struct task_struct *task = get_proc_task(inode);
638
639 length = -ESRCH;
640 if (!task)
641 goto out_no_task;
642
643 if (count > PROC_BLOCK_SIZE)
644 count = PROC_BLOCK_SIZE;
645
646 length = -ENOMEM;
647 if (!(page = __get_free_page(GFP_TEMPORARY)))
648 goto out;
649
650 length = PROC_I(inode)->op.proc_read(task, (char*)page);
651
652 if (length >= 0)
653 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
654 free_page(page);
655 out:
656 put_task_struct(task);
657 out_no_task:
658 return length;
659 }
660
661 static const struct file_operations proc_info_file_operations = {
662 .read = proc_info_read,
663 };
664
665 static int proc_single_show(struct seq_file *m, void *v)
666 {
667 struct inode *inode = m->private;
668 struct pid_namespace *ns;
669 struct pid *pid;
670 struct task_struct *task;
671 int ret;
672
673 ns = inode->i_sb->s_fs_info;
674 pid = proc_pid(inode);
675 task = get_pid_task(pid, PIDTYPE_PID);
676 if (!task)
677 return -ESRCH;
678
679 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
680
681 put_task_struct(task);
682 return ret;
683 }
684
685 static int proc_single_open(struct inode *inode, struct file *filp)
686 {
687 int ret;
688 ret = single_open(filp, proc_single_show, NULL);
689 if (!ret) {
690 struct seq_file *m = filp->private_data;
691
692 m->private = inode;
693 }
694 return ret;
695 }
696
697 static const struct file_operations proc_single_file_operations = {
698 .open = proc_single_open,
699 .read = seq_read,
700 .llseek = seq_lseek,
701 .release = single_release,
702 };
703
704 static int mem_open(struct inode* inode, struct file* file)
705 {
706 file->private_data = (void*)((long)current->self_exec_id);
707 return 0;
708 }
709
710 static ssize_t mem_read(struct file * file, char __user * buf,
711 size_t count, loff_t *ppos)
712 {
713 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
714 char *page;
715 unsigned long src = *ppos;
716 int ret = -ESRCH;
717 struct mm_struct *mm;
718
719 if (!task)
720 goto out_no_task;
721
722 if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
723 goto out;
724
725 ret = -ENOMEM;
726 page = (char *)__get_free_page(GFP_TEMPORARY);
727 if (!page)
728 goto out;
729
730 ret = 0;
731
732 mm = get_task_mm(task);
733 if (!mm)
734 goto out_free;
735
736 ret = -EIO;
737
738 if (file->private_data != (void*)((long)current->self_exec_id))
739 goto out_put;
740
741 ret = 0;
742
743 while (count > 0) {
744 int this_len, retval;
745
746 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
747 retval = access_process_vm(task, src, page, this_len, 0);
748 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) {
749 if (!ret)
750 ret = -EIO;
751 break;
752 }
753
754 if (copy_to_user(buf, page, retval)) {
755 ret = -EFAULT;
756 break;
757 }
758
759 ret += retval;
760 src += retval;
761 buf += retval;
762 count -= retval;
763 }
764 *ppos = src;
765
766 out_put:
767 mmput(mm);
768 out_free:
769 free_page((unsigned long) page);
770 out:
771 put_task_struct(task);
772 out_no_task:
773 return ret;
774 }
775
776 #define mem_write NULL
777
778 #ifndef mem_write
779 /* This is a security hazard */
780 static ssize_t mem_write(struct file * file, const char __user *buf,
781 size_t count, loff_t *ppos)
782 {
783 int copied;
784 char *page;
785 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
786 unsigned long dst = *ppos;
787
788 copied = -ESRCH;
789 if (!task)
790 goto out_no_task;
791
792 if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
793 goto out;
794
795 copied = -ENOMEM;
796 page = (char *)__get_free_page(GFP_TEMPORARY);
797 if (!page)
798 goto out;
799
800 copied = 0;
801 while (count > 0) {
802 int this_len, retval;
803
804 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
805 if (copy_from_user(page, buf, this_len)) {
806 copied = -EFAULT;
807 break;
808 }
809 retval = access_process_vm(task, dst, page, this_len, 1);
810 if (!retval) {
811 if (!copied)
812 copied = -EIO;
813 break;
814 }
815 copied += retval;
816 buf += retval;
817 dst += retval;
818 count -= retval;
819 }
820 *ppos = dst;
821 free_page((unsigned long) page);
822 out:
823 put_task_struct(task);
824 out_no_task:
825 return copied;
826 }
827 #endif
828
829 loff_t mem_lseek(struct file *file, loff_t offset, int orig)
830 {
831 switch (orig) {
832 case 0:
833 file->f_pos = offset;
834 break;
835 case 1:
836 file->f_pos += offset;
837 break;
838 default:
839 return -EINVAL;
840 }
841 force_successful_syscall_return();
842 return file->f_pos;
843 }
844
845 static const struct file_operations proc_mem_operations = {
846 .llseek = mem_lseek,
847 .read = mem_read,
848 .write = mem_write,
849 .open = mem_open,
850 };
851
852 static ssize_t environ_read(struct file *file, char __user *buf,
853 size_t count, loff_t *ppos)
854 {
855 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
856 char *page;
857 unsigned long src = *ppos;
858 int ret = -ESRCH;
859 struct mm_struct *mm;
860
861 if (!task)
862 goto out_no_task;
863
864 if (!ptrace_may_attach(task))
865 goto out;
866
867 ret = -ENOMEM;
868 page = (char *)__get_free_page(GFP_TEMPORARY);
869 if (!page)
870 goto out;
871
872 ret = 0;
873
874 mm = get_task_mm(task);
875 if (!mm)
876 goto out_free;
877
878 while (count > 0) {
879 int this_len, retval, max_len;
880
881 this_len = mm->env_end - (mm->env_start + src);
882
883 if (this_len <= 0)
884 break;
885
886 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
887 this_len = (this_len > max_len) ? max_len : this_len;
888
889 retval = access_process_vm(task, (mm->env_start + src),
890 page, this_len, 0);
891
892 if (retval <= 0) {
893 ret = retval;
894 break;
895 }
896
897 if (copy_to_user(buf, page, retval)) {
898 ret = -EFAULT;
899 break;
900 }
901
902 ret += retval;
903 src += retval;
904 buf += retval;
905 count -= retval;
906 }
907 *ppos = src;
908
909 mmput(mm);
910 out_free:
911 free_page((unsigned long) page);
912 out:
913 put_task_struct(task);
914 out_no_task:
915 return ret;
916 }
917
918 static const struct file_operations proc_environ_operations = {
919 .read = environ_read,
920 };
921
922 static ssize_t oom_adjust_read(struct file *file, char __user *buf,
923 size_t count, loff_t *ppos)
924 {
925 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
926 char buffer[PROC_NUMBUF];
927 size_t len;
928 int oom_adjust;
929
930 if (!task)
931 return -ESRCH;
932 oom_adjust = task->oomkilladj;
933 put_task_struct(task);
934
935 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
936
937 return simple_read_from_buffer(buf, count, ppos, buffer, len);
938 }
939
940 static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
941 size_t count, loff_t *ppos)
942 {
943 struct task_struct *task;
944 char buffer[PROC_NUMBUF], *end;
945 int oom_adjust;
946
947 memset(buffer, 0, sizeof(buffer));
948 if (count > sizeof(buffer) - 1)
949 count = sizeof(buffer) - 1;
950 if (copy_from_user(buffer, buf, count))
951 return -EFAULT;
952 oom_adjust = simple_strtol(buffer, &end, 0);
953 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
954 oom_adjust != OOM_DISABLE)
955 return -EINVAL;
956 if (*end == '\n')
957 end++;
958 task = get_proc_task(file->f_path.dentry->d_inode);
959 if (!task)
960 return -ESRCH;
961 if (oom_adjust < task->oomkilladj && !capable(CAP_SYS_RESOURCE)) {
962 put_task_struct(task);
963 return -EACCES;
964 }
965 task->oomkilladj = oom_adjust;
966 put_task_struct(task);
967 if (end - buffer == 0)
968 return -EIO;
969 return end - buffer;
970 }
971
972 static const struct file_operations proc_oom_adjust_operations = {
973 .read = oom_adjust_read,
974 .write = oom_adjust_write,
975 };
976
977 #ifdef CONFIG_AUDITSYSCALL
978 #define TMPBUFLEN 21
979 static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
980 size_t count, loff_t *ppos)
981 {
982 struct inode * inode = file->f_path.dentry->d_inode;
983 struct task_struct *task = get_proc_task(inode);
984 ssize_t length;
985 char tmpbuf[TMPBUFLEN];
986
987 if (!task)
988 return -ESRCH;
989 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
990 audit_get_loginuid(task));
991 put_task_struct(task);
992 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
993 }
994
995 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
996 size_t count, loff_t *ppos)
997 {
998 struct inode * inode = file->f_path.dentry->d_inode;
999 char *page, *tmp;
1000 ssize_t length;
1001 uid_t loginuid;
1002
1003 if (!capable(CAP_AUDIT_CONTROL))
1004 return -EPERM;
1005
1006 if (current != pid_task(proc_pid(inode), PIDTYPE_PID))
1007 return -EPERM;
1008
1009 if (count >= PAGE_SIZE)
1010 count = PAGE_SIZE - 1;
1011
1012 if (*ppos != 0) {
1013 /* No partial writes. */
1014 return -EINVAL;
1015 }
1016 page = (char*)__get_free_page(GFP_TEMPORARY);
1017 if (!page)
1018 return -ENOMEM;
1019 length = -EFAULT;
1020 if (copy_from_user(page, buf, count))
1021 goto out_free_page;
1022
1023 page[count] = '\0';
1024 loginuid = simple_strtoul(page, &tmp, 10);
1025 if (tmp == page) {
1026 length = -EINVAL;
1027 goto out_free_page;
1028
1029 }
1030 length = audit_set_loginuid(current, loginuid);
1031 if (likely(length == 0))
1032 length = count;
1033
1034 out_free_page:
1035 free_page((unsigned long) page);
1036 return length;
1037 }
1038
1039 static const struct file_operations proc_loginuid_operations = {
1040 .read = proc_loginuid_read,
1041 .write = proc_loginuid_write,
1042 };
1043 #endif
1044
1045 #ifdef CONFIG_FAULT_INJECTION
1046 static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1047 size_t count, loff_t *ppos)
1048 {
1049 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1050 char buffer[PROC_NUMBUF];
1051 size_t len;
1052 int make_it_fail;
1053
1054 if (!task)
1055 return -ESRCH;
1056 make_it_fail = task->make_it_fail;
1057 put_task_struct(task);
1058
1059 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
1060
1061 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1062 }
1063
1064 static ssize_t proc_fault_inject_write(struct file * file,
1065 const char __user * buf, size_t count, loff_t *ppos)
1066 {
1067 struct task_struct *task;
1068 char buffer[PROC_NUMBUF], *end;
1069 int make_it_fail;
1070
1071 if (!capable(CAP_SYS_RESOURCE))
1072 return -EPERM;
1073 memset(buffer, 0, sizeof(buffer));
1074 if (count > sizeof(buffer) - 1)
1075 count = sizeof(buffer) - 1;
1076 if (copy_from_user(buffer, buf, count))
1077 return -EFAULT;
1078 make_it_fail = simple_strtol(buffer, &end, 0);
1079 if (*end == '\n')
1080 end++;
1081 task = get_proc_task(file->f_dentry->d_inode);
1082 if (!task)
1083 return -ESRCH;
1084 task->make_it_fail = make_it_fail;
1085 put_task_struct(task);
1086 if (end - buffer == 0)
1087 return -EIO;
1088 return end - buffer;
1089 }
1090
1091 static const struct file_operations proc_fault_inject_operations = {
1092 .read = proc_fault_inject_read,
1093 .write = proc_fault_inject_write,
1094 };
1095 #endif
1096
1097
1098 #ifdef CONFIG_SCHED_DEBUG
1099 /*
1100 * Print out various scheduling related per-task fields:
1101 */
1102 static int sched_show(struct seq_file *m, void *v)
1103 {
1104 struct inode *inode = m->private;
1105 struct task_struct *p;
1106
1107 WARN_ON(!inode);
1108
1109 p = get_proc_task(inode);
1110 if (!p)
1111 return -ESRCH;
1112 proc_sched_show_task(p, m);
1113
1114 put_task_struct(p);
1115
1116 return 0;
1117 }
1118
1119 static ssize_t
1120 sched_write(struct file *file, const char __user *buf,
1121 size_t count, loff_t *offset)
1122 {
1123 struct inode *inode = file->f_path.dentry->d_inode;
1124 struct task_struct *p;
1125
1126 WARN_ON(!inode);
1127
1128 p = get_proc_task(inode);
1129 if (!p)
1130 return -ESRCH;
1131 proc_sched_set_task(p);
1132
1133 put_task_struct(p);
1134
1135 return count;
1136 }
1137
1138 static int sched_open(struct inode *inode, struct file *filp)
1139 {
1140 int ret;
1141
1142 ret = single_open(filp, sched_show, NULL);
1143 if (!ret) {
1144 struct seq_file *m = filp->private_data;
1145
1146 m->private = inode;
1147 }
1148 return ret;
1149 }
1150
1151 static const struct file_operations proc_pid_sched_operations = {
1152 .open = sched_open,
1153 .read = seq_read,
1154 .write = sched_write,
1155 .llseek = seq_lseek,
1156 .release = single_release,
1157 };
1158
1159 #endif
1160
1161 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1162 {
1163 struct inode *inode = dentry->d_inode;
1164 int error = -EACCES;
1165
1166 /* We don't need a base pointer in the /proc filesystem */
1167 path_put(&nd->path);
1168
1169 /* Are we allowed to snoop on the tasks file descriptors? */
1170 if (!proc_fd_access_allowed(inode))
1171 goto out;
1172
1173 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
1174 nd->last_type = LAST_BIND;
1175 out:
1176 return ERR_PTR(error);
1177 }
1178
1179 static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1180 {
1181 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
1182 char *pathname;
1183 int len;
1184
1185 if (!tmp)
1186 return -ENOMEM;
1187
1188 pathname = d_path(path, tmp, PAGE_SIZE);
1189 len = PTR_ERR(pathname);
1190 if (IS_ERR(pathname))
1191 goto out;
1192 len = tmp + PAGE_SIZE - 1 - pathname;
1193
1194 if (len > buflen)
1195 len = buflen;
1196 if (copy_to_user(buffer, pathname, len))
1197 len = -EFAULT;
1198 out:
1199 free_page((unsigned long)tmp);
1200 return len;
1201 }
1202
1203 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1204 {
1205 int error = -EACCES;
1206 struct inode *inode = dentry->d_inode;
1207 struct path path;
1208
1209 /* Are we allowed to snoop on the tasks file descriptors? */
1210 if (!proc_fd_access_allowed(inode))
1211 goto out;
1212
1213 error = PROC_I(inode)->op.proc_get_link(inode, &path);
1214 if (error)
1215 goto out;
1216
1217 error = do_proc_readlink(&path, buffer, buflen);
1218 path_put(&path);
1219 out:
1220 return error;
1221 }
1222
1223 static const struct inode_operations proc_pid_link_inode_operations = {
1224 .readlink = proc_pid_readlink,
1225 .follow_link = proc_pid_follow_link,
1226 .setattr = proc_setattr,
1227 };
1228
1229
1230 /* building an inode */
1231
1232 static int task_dumpable(struct task_struct *task)
1233 {
1234 int dumpable = 0;
1235 struct mm_struct *mm;
1236
1237 task_lock(task);
1238 mm = task->mm;
1239 if (mm)
1240 dumpable = get_dumpable(mm);
1241 task_unlock(task);
1242 if(dumpable == 1)
1243 return 1;
1244 return 0;
1245 }
1246
1247
1248 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
1249 {
1250 struct inode * inode;
1251 struct proc_inode *ei;
1252
1253 /* We need a new inode */
1254
1255 inode = new_inode(sb);
1256 if (!inode)
1257 goto out;
1258
1259 /* Common stuff */
1260 ei = PROC_I(inode);
1261 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1262 inode->i_op = &proc_def_inode_operations;
1263
1264 /*
1265 * grab the reference to task.
1266 */
1267 ei->pid = get_task_pid(task, PIDTYPE_PID);
1268 if (!ei->pid)
1269 goto out_unlock;
1270
1271 inode->i_uid = 0;
1272 inode->i_gid = 0;
1273 if (task_dumpable(task)) {
1274 inode->i_uid = task->euid;
1275 inode->i_gid = task->egid;
1276 }
1277 security_task_to_inode(task, inode);
1278
1279 out:
1280 return inode;
1281
1282 out_unlock:
1283 iput(inode);
1284 return NULL;
1285 }
1286
1287 static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1288 {
1289 struct inode *inode = dentry->d_inode;
1290 struct task_struct *task;
1291 generic_fillattr(inode, stat);
1292
1293 rcu_read_lock();
1294 stat->uid = 0;
1295 stat->gid = 0;
1296 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1297 if (task) {
1298 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1299 task_dumpable(task)) {
1300 stat->uid = task->euid;
1301 stat->gid = task->egid;
1302 }
1303 }
1304 rcu_read_unlock();
1305 return 0;
1306 }
1307
1308 /* dentry stuff */
1309
1310 /*
1311 * Exceptional case: normally we are not allowed to unhash a busy
1312 * directory. In this case, however, we can do it - no aliasing problems
1313 * due to the way we treat inodes.
1314 *
1315 * Rewrite the inode's ownerships here because the owning task may have
1316 * performed a setuid(), etc.
1317 *
1318 * Before the /proc/pid/status file was created the only way to read
1319 * the effective uid of a /process was to stat /proc/pid. Reading
1320 * /proc/pid/status is slow enough that procps and other packages
1321 * kept stating /proc/pid. To keep the rules in /proc simple I have
1322 * made this apply to all per process world readable and executable
1323 * directories.
1324 */
1325 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1326 {
1327 struct inode *inode = dentry->d_inode;
1328 struct task_struct *task = get_proc_task(inode);
1329 if (task) {
1330 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1331 task_dumpable(task)) {
1332 inode->i_uid = task->euid;
1333 inode->i_gid = task->egid;
1334 } else {
1335 inode->i_uid = 0;
1336 inode->i_gid = 0;
1337 }
1338 inode->i_mode &= ~(S_ISUID | S_ISGID);
1339 security_task_to_inode(task, inode);
1340 put_task_struct(task);
1341 return 1;
1342 }
1343 d_drop(dentry);
1344 return 0;
1345 }
1346
1347 static int pid_delete_dentry(struct dentry * dentry)
1348 {
1349 /* Is the task we represent dead?
1350 * If so, then don't put the dentry on the lru list,
1351 * kill it immediately.
1352 */
1353 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1354 }
1355
1356 static struct dentry_operations pid_dentry_operations =
1357 {
1358 .d_revalidate = pid_revalidate,
1359 .d_delete = pid_delete_dentry,
1360 };
1361
1362 /* Lookups */
1363
1364 typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
1365 struct task_struct *, const void *);
1366
1367 /*
1368 * Fill a directory entry.
1369 *
1370 * If possible create the dcache entry and derive our inode number and
1371 * file type from dcache entry.
1372 *
1373 * Since all of the proc inode numbers are dynamically generated, the inode
1374 * numbers do not exist until the inode is cache. This means creating the
1375 * the dcache entry in readdir is necessary to keep the inode numbers
1376 * reported by readdir in sync with the inode numbers reported
1377 * by stat.
1378 */
1379 static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1380 char *name, int len,
1381 instantiate_t instantiate, struct task_struct *task, const void *ptr)
1382 {
1383 struct dentry *child, *dir = filp->f_path.dentry;
1384 struct inode *inode;
1385 struct qstr qname;
1386 ino_t ino = 0;
1387 unsigned type = DT_UNKNOWN;
1388
1389 qname.name = name;
1390 qname.len = len;
1391 qname.hash = full_name_hash(name, len);
1392
1393 child = d_lookup(dir, &qname);
1394 if (!child) {
1395 struct dentry *new;
1396 new = d_alloc(dir, &qname);
1397 if (new) {
1398 child = instantiate(dir->d_inode, new, task, ptr);
1399 if (child)
1400 dput(new);
1401 else
1402 child = new;
1403 }
1404 }
1405 if (!child || IS_ERR(child) || !child->d_inode)
1406 goto end_instantiate;
1407 inode = child->d_inode;
1408 if (inode) {
1409 ino = inode->i_ino;
1410 type = inode->i_mode >> 12;
1411 }
1412 dput(child);
1413 end_instantiate:
1414 if (!ino)
1415 ino = find_inode_number(dir, &qname);
1416 if (!ino)
1417 ino = 1;
1418 return filldir(dirent, name, len, filp->f_pos, ino, type);
1419 }
1420
1421 static unsigned name_to_int(struct dentry *dentry)
1422 {
1423 const char *name = dentry->d_name.name;
1424 int len = dentry->d_name.len;
1425 unsigned n = 0;
1426
1427 if (len > 1 && *name == '0')
1428 goto out;
1429 while (len-- > 0) {
1430 unsigned c = *name++ - '0';
1431 if (c > 9)
1432 goto out;
1433 if (n >= (~0U-9)/10)
1434 goto out;
1435 n *= 10;
1436 n += c;
1437 }
1438 return n;
1439 out:
1440 return ~0U;
1441 }
1442
1443 #define PROC_FDINFO_MAX 64
1444
1445 static int proc_fd_info(struct inode *inode, struct path *path, char *info)
1446 {
1447 struct task_struct *task = get_proc_task(inode);
1448 struct files_struct *files = NULL;
1449 struct file *file;
1450 int fd = proc_fd(inode);
1451
1452 if (task) {
1453 files = get_files_struct(task);
1454 put_task_struct(task);
1455 }
1456 if (files) {
1457 /*
1458 * We are not taking a ref to the file structure, so we must
1459 * hold ->file_lock.
1460 */
1461 spin_lock(&files->file_lock);
1462 file = fcheck_files(files, fd);
1463 if (file) {
1464 if (path) {
1465 *path = file->f_path;
1466 path_get(&file->f_path);
1467 }
1468 if (info)
1469 snprintf(info, PROC_FDINFO_MAX,
1470 "pos:\t%lli\n"
1471 "flags:\t0%o\n",
1472 (long long) file->f_pos,
1473 file->f_flags);
1474 spin_unlock(&files->file_lock);
1475 put_files_struct(files);
1476 return 0;
1477 }
1478 spin_unlock(&files->file_lock);
1479 put_files_struct(files);
1480 }
1481 return -ENOENT;
1482 }
1483
1484 static int proc_fd_link(struct inode *inode, struct path *path)
1485 {
1486 return proc_fd_info(inode, path, NULL);
1487 }
1488
1489 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1490 {
1491 struct inode *inode = dentry->d_inode;
1492 struct task_struct *task = get_proc_task(inode);
1493 int fd = proc_fd(inode);
1494 struct files_struct *files;
1495
1496 if (task) {
1497 files = get_files_struct(task);
1498 if (files) {
1499 rcu_read_lock();
1500 if (fcheck_files(files, fd)) {
1501 rcu_read_unlock();
1502 put_files_struct(files);
1503 if (task_dumpable(task)) {
1504 inode->i_uid = task->euid;
1505 inode->i_gid = task->egid;
1506 } else {
1507 inode->i_uid = 0;
1508 inode->i_gid = 0;
1509 }
1510 inode->i_mode &= ~(S_ISUID | S_ISGID);
1511 security_task_to_inode(task, inode);
1512 put_task_struct(task);
1513 return 1;
1514 }
1515 rcu_read_unlock();
1516 put_files_struct(files);
1517 }
1518 put_task_struct(task);
1519 }
1520 d_drop(dentry);
1521 return 0;
1522 }
1523
1524 static struct dentry_operations tid_fd_dentry_operations =
1525 {
1526 .d_revalidate = tid_fd_revalidate,
1527 .d_delete = pid_delete_dentry,
1528 };
1529
1530 static struct dentry *proc_fd_instantiate(struct inode *dir,
1531 struct dentry *dentry, struct task_struct *task, const void *ptr)
1532 {
1533 unsigned fd = *(const unsigned *)ptr;
1534 struct file *file;
1535 struct files_struct *files;
1536 struct inode *inode;
1537 struct proc_inode *ei;
1538 struct dentry *error = ERR_PTR(-ENOENT);
1539
1540 inode = proc_pid_make_inode(dir->i_sb, task);
1541 if (!inode)
1542 goto out;
1543 ei = PROC_I(inode);
1544 ei->fd = fd;
1545 files = get_files_struct(task);
1546 if (!files)
1547 goto out_iput;
1548 inode->i_mode = S_IFLNK;
1549
1550 /*
1551 * We are not taking a ref to the file structure, so we must
1552 * hold ->file_lock.
1553 */
1554 spin_lock(&files->file_lock);
1555 file = fcheck_files(files, fd);
1556 if (!file)
1557 goto out_unlock;
1558 if (file->f_mode & 1)
1559 inode->i_mode |= S_IRUSR | S_IXUSR;
1560 if (file->f_mode & 2)
1561 inode->i_mode |= S_IWUSR | S_IXUSR;
1562 spin_unlock(&files->file_lock);
1563 put_files_struct(files);
1564
1565 inode->i_op = &proc_pid_link_inode_operations;
1566 inode->i_size = 64;
1567 ei->op.proc_get_link = proc_fd_link;
1568 dentry->d_op = &tid_fd_dentry_operations;
1569 d_add(dentry, inode);
1570 /* Close the race of the process dying before we return the dentry */
1571 if (tid_fd_revalidate(dentry, NULL))
1572 error = NULL;
1573
1574 out:
1575 return error;
1576 out_unlock:
1577 spin_unlock(&files->file_lock);
1578 put_files_struct(files);
1579 out_iput:
1580 iput(inode);
1581 goto out;
1582 }
1583
1584 static struct dentry *proc_lookupfd_common(struct inode *dir,
1585 struct dentry *dentry,
1586 instantiate_t instantiate)
1587 {
1588 struct task_struct *task = get_proc_task(dir);
1589 unsigned fd = name_to_int(dentry);
1590 struct dentry *result = ERR_PTR(-ENOENT);
1591
1592 if (!task)
1593 goto out_no_task;
1594 if (fd == ~0U)
1595 goto out;
1596
1597 result = instantiate(dir, dentry, task, &fd);
1598 out:
1599 put_task_struct(task);
1600 out_no_task:
1601 return result;
1602 }
1603
1604 static int proc_readfd_common(struct file * filp, void * dirent,
1605 filldir_t filldir, instantiate_t instantiate)
1606 {
1607 struct dentry *dentry = filp->f_path.dentry;
1608 struct inode *inode = dentry->d_inode;
1609 struct task_struct *p = get_proc_task(inode);
1610 unsigned int fd, ino;
1611 int retval;
1612 struct files_struct * files;
1613 struct fdtable *fdt;
1614
1615 retval = -ENOENT;
1616 if (!p)
1617 goto out_no_task;
1618 retval = 0;
1619
1620 fd = filp->f_pos;
1621 switch (fd) {
1622 case 0:
1623 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
1624 goto out;
1625 filp->f_pos++;
1626 case 1:
1627 ino = parent_ino(dentry);
1628 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
1629 goto out;
1630 filp->f_pos++;
1631 default:
1632 files = get_files_struct(p);
1633 if (!files)
1634 goto out;
1635 rcu_read_lock();
1636 fdt = files_fdtable(files);
1637 for (fd = filp->f_pos-2;
1638 fd < fdt->max_fds;
1639 fd++, filp->f_pos++) {
1640 char name[PROC_NUMBUF];
1641 int len;
1642
1643 if (!fcheck_files(files, fd))
1644 continue;
1645 rcu_read_unlock();
1646
1647 len = snprintf(name, sizeof(name), "%d", fd);
1648 if (proc_fill_cache(filp, dirent, filldir,
1649 name, len, instantiate,
1650 p, &fd) < 0) {
1651 rcu_read_lock();
1652 break;
1653 }
1654 rcu_read_lock();
1655 }
1656 rcu_read_unlock();
1657 put_files_struct(files);
1658 }
1659 out:
1660 put_task_struct(p);
1661 out_no_task:
1662 return retval;
1663 }
1664
1665 static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
1666 struct nameidata *nd)
1667 {
1668 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
1669 }
1670
1671 static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
1672 {
1673 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
1674 }
1675
1676 static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
1677 size_t len, loff_t *ppos)
1678 {
1679 char tmp[PROC_FDINFO_MAX];
1680 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
1681 if (!err)
1682 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
1683 return err;
1684 }
1685
1686 static const struct file_operations proc_fdinfo_file_operations = {
1687 .open = nonseekable_open,
1688 .read = proc_fdinfo_read,
1689 };
1690
1691 static const struct file_operations proc_fd_operations = {
1692 .read = generic_read_dir,
1693 .readdir = proc_readfd,
1694 };
1695
1696 /*
1697 * /proc/pid/fd needs a special permission handler so that a process can still
1698 * access /proc/self/fd after it has executed a setuid().
1699 */
1700 static int proc_fd_permission(struct inode *inode, int mask,
1701 struct nameidata *nd)
1702 {
1703 int rv;
1704
1705 rv = generic_permission(inode, mask, NULL);
1706 if (rv == 0)
1707 return 0;
1708 if (task_pid(current) == proc_pid(inode))
1709 rv = 0;
1710 return rv;
1711 }
1712
1713 /*
1714 * proc directories can do almost nothing..
1715 */
1716 static const struct inode_operations proc_fd_inode_operations = {
1717 .lookup = proc_lookupfd,
1718 .permission = proc_fd_permission,
1719 .setattr = proc_setattr,
1720 };
1721
1722 static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
1723 struct dentry *dentry, struct task_struct *task, const void *ptr)
1724 {
1725 unsigned fd = *(unsigned *)ptr;
1726 struct inode *inode;
1727 struct proc_inode *ei;
1728 struct dentry *error = ERR_PTR(-ENOENT);
1729
1730 inode = proc_pid_make_inode(dir->i_sb, task);
1731 if (!inode)
1732 goto out;
1733 ei = PROC_I(inode);
1734 ei->fd = fd;
1735 inode->i_mode = S_IFREG | S_IRUSR;
1736 inode->i_fop = &proc_fdinfo_file_operations;
1737 dentry->d_op = &tid_fd_dentry_operations;
1738 d_add(dentry, inode);
1739 /* Close the race of the process dying before we return the dentry */
1740 if (tid_fd_revalidate(dentry, NULL))
1741 error = NULL;
1742
1743 out:
1744 return error;
1745 }
1746
1747 static struct dentry *proc_lookupfdinfo(struct inode *dir,
1748 struct dentry *dentry,
1749 struct nameidata *nd)
1750 {
1751 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
1752 }
1753
1754 static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
1755 {
1756 return proc_readfd_common(filp, dirent, filldir,
1757 proc_fdinfo_instantiate);
1758 }
1759
1760 static const struct file_operations proc_fdinfo_operations = {
1761 .read = generic_read_dir,
1762 .readdir = proc_readfdinfo,
1763 };
1764
1765 /*
1766 * proc directories can do almost nothing..
1767 */
1768 static const struct inode_operations proc_fdinfo_inode_operations = {
1769 .lookup = proc_lookupfdinfo,
1770 .setattr = proc_setattr,
1771 };
1772
1773
1774 static struct dentry *proc_pident_instantiate(struct inode *dir,
1775 struct dentry *dentry, struct task_struct *task, const void *ptr)
1776 {
1777 const struct pid_entry *p = ptr;
1778 struct inode *inode;
1779 struct proc_inode *ei;
1780 struct dentry *error = ERR_PTR(-EINVAL);
1781
1782 inode = proc_pid_make_inode(dir->i_sb, task);
1783 if (!inode)
1784 goto out;
1785
1786 ei = PROC_I(inode);
1787 inode->i_mode = p->mode;
1788 if (S_ISDIR(inode->i_mode))
1789 inode->i_nlink = 2; /* Use getattr to fix if necessary */
1790 if (p->iop)
1791 inode->i_op = p->iop;
1792 if (p->fop)
1793 inode->i_fop = p->fop;
1794 ei->op = p->op;
1795 dentry->d_op = &pid_dentry_operations;
1796 d_add(dentry, inode);
1797 /* Close the race of the process dying before we return the dentry */
1798 if (pid_revalidate(dentry, NULL))
1799 error = NULL;
1800 out:
1801 return error;
1802 }
1803
1804 static struct dentry *proc_pident_lookup(struct inode *dir,
1805 struct dentry *dentry,
1806 const struct pid_entry *ents,
1807 unsigned int nents)
1808 {
1809 struct inode *inode;
1810 struct dentry *error;
1811 struct task_struct *task = get_proc_task(dir);
1812 const struct pid_entry *p, *last;
1813
1814 error = ERR_PTR(-ENOENT);
1815 inode = NULL;
1816
1817 if (!task)
1818 goto out_no_task;
1819
1820 /*
1821 * Yes, it does not scale. And it should not. Don't add
1822 * new entries into /proc/<tgid>/ without very good reasons.
1823 */
1824 last = &ents[nents - 1];
1825 for (p = ents; p <= last; p++) {
1826 if (p->len != dentry->d_name.len)
1827 continue;
1828 if (!memcmp(dentry->d_name.name, p->name, p->len))
1829 break;
1830 }
1831 if (p > last)
1832 goto out;
1833
1834 error = proc_pident_instantiate(dir, dentry, task, p);
1835 out:
1836 put_task_struct(task);
1837 out_no_task:
1838 return error;
1839 }
1840
1841 static int proc_pident_fill_cache(struct file *filp, void *dirent,
1842 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
1843 {
1844 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
1845 proc_pident_instantiate, task, p);
1846 }
1847
1848 static int proc_pident_readdir(struct file *filp,
1849 void *dirent, filldir_t filldir,
1850 const struct pid_entry *ents, unsigned int nents)
1851 {
1852 int i;
1853 struct dentry *dentry = filp->f_path.dentry;
1854 struct inode *inode = dentry->d_inode;
1855 struct task_struct *task = get_proc_task(inode);
1856 const struct pid_entry *p, *last;
1857 ino_t ino;
1858 int ret;
1859
1860 ret = -ENOENT;
1861 if (!task)
1862 goto out_no_task;
1863
1864 ret = 0;
1865 i = filp->f_pos;
1866 switch (i) {
1867 case 0:
1868 ino = inode->i_ino;
1869 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
1870 goto out;
1871 i++;
1872 filp->f_pos++;
1873 /* fall through */
1874 case 1:
1875 ino = parent_ino(dentry);
1876 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
1877 goto out;
1878 i++;
1879 filp->f_pos++;
1880 /* fall through */
1881 default:
1882 i -= 2;
1883 if (i >= nents) {
1884 ret = 1;
1885 goto out;
1886 }
1887 p = ents + i;
1888 last = &ents[nents - 1];
1889 while (p <= last) {
1890 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
1891 goto out;
1892 filp->f_pos++;
1893 p++;
1894 }
1895 }
1896
1897 ret = 1;
1898 out:
1899 put_task_struct(task);
1900 out_no_task:
1901 return ret;
1902 }
1903
1904 #ifdef CONFIG_SECURITY
1905 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
1906 size_t count, loff_t *ppos)
1907 {
1908 struct inode * inode = file->f_path.dentry->d_inode;
1909 char *p = NULL;
1910 ssize_t length;
1911 struct task_struct *task = get_proc_task(inode);
1912
1913 if (!task)
1914 return -ESRCH;
1915
1916 length = security_getprocattr(task,
1917 (char*)file->f_path.dentry->d_name.name,
1918 &p);
1919 put_task_struct(task);
1920 if (length > 0)
1921 length = simple_read_from_buffer(buf, count, ppos, p, length);
1922 kfree(p);
1923 return length;
1924 }
1925
1926 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
1927 size_t count, loff_t *ppos)
1928 {
1929 struct inode * inode = file->f_path.dentry->d_inode;
1930 char *page;
1931 ssize_t length;
1932 struct task_struct *task = get_proc_task(inode);
1933
1934 length = -ESRCH;
1935 if (!task)
1936 goto out_no_task;
1937 if (count > PAGE_SIZE)
1938 count = PAGE_SIZE;
1939
1940 /* No partial writes. */
1941 length = -EINVAL;
1942 if (*ppos != 0)
1943 goto out;
1944
1945 length = -ENOMEM;
1946 page = (char*)__get_free_page(GFP_TEMPORARY);
1947 if (!page)
1948 goto out;
1949
1950 length = -EFAULT;
1951 if (copy_from_user(page, buf, count))
1952 goto out_free;
1953
1954 length = security_setprocattr(task,
1955 (char*)file->f_path.dentry->d_name.name,
1956 (void*)page, count);
1957 out_free:
1958 free_page((unsigned long) page);
1959 out:
1960 put_task_struct(task);
1961 out_no_task:
1962 return length;
1963 }
1964
1965 static const struct file_operations proc_pid_attr_operations = {
1966 .read = proc_pid_attr_read,
1967 .write = proc_pid_attr_write,
1968 };
1969
1970 static const struct pid_entry attr_dir_stuff[] = {
1971 REG("current", S_IRUGO|S_IWUGO, pid_attr),
1972 REG("prev", S_IRUGO, pid_attr),
1973 REG("exec", S_IRUGO|S_IWUGO, pid_attr),
1974 REG("fscreate", S_IRUGO|S_IWUGO, pid_attr),
1975 REG("keycreate", S_IRUGO|S_IWUGO, pid_attr),
1976 REG("sockcreate", S_IRUGO|S_IWUGO, pid_attr),
1977 };
1978
1979 static int proc_attr_dir_readdir(struct file * filp,
1980 void * dirent, filldir_t filldir)
1981 {
1982 return proc_pident_readdir(filp,dirent,filldir,
1983 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
1984 }
1985
1986 static const struct file_operations proc_attr_dir_operations = {
1987 .read = generic_read_dir,
1988 .readdir = proc_attr_dir_readdir,
1989 };
1990
1991 static struct dentry *proc_attr_dir_lookup(struct inode *dir,
1992 struct dentry *dentry, struct nameidata *nd)
1993 {
1994 return proc_pident_lookup(dir, dentry,
1995 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
1996 }
1997
1998 static const struct inode_operations proc_attr_dir_inode_operations = {
1999 .lookup = proc_attr_dir_lookup,
2000 .getattr = pid_getattr,
2001 .setattr = proc_setattr,
2002 };
2003
2004 #endif
2005
2006 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
2007 static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2008 size_t count, loff_t *ppos)
2009 {
2010 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2011 struct mm_struct *mm;
2012 char buffer[PROC_NUMBUF];
2013 size_t len;
2014 int ret;
2015
2016 if (!task)
2017 return -ESRCH;
2018
2019 ret = 0;
2020 mm = get_task_mm(task);
2021 if (mm) {
2022 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2023 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2024 MMF_DUMP_FILTER_SHIFT));
2025 mmput(mm);
2026 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2027 }
2028
2029 put_task_struct(task);
2030
2031 return ret;
2032 }
2033
2034 static ssize_t proc_coredump_filter_write(struct file *file,
2035 const char __user *buf,
2036 size_t count,
2037 loff_t *ppos)
2038 {
2039 struct task_struct *task;
2040 struct mm_struct *mm;
2041 char buffer[PROC_NUMBUF], *end;
2042 unsigned int val;
2043 int ret;
2044 int i;
2045 unsigned long mask;
2046
2047 ret = -EFAULT;
2048 memset(buffer, 0, sizeof(buffer));
2049 if (count > sizeof(buffer) - 1)
2050 count = sizeof(buffer) - 1;
2051 if (copy_from_user(buffer, buf, count))
2052 goto out_no_task;
2053
2054 ret = -EINVAL;
2055 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2056 if (*end == '\n')
2057 end++;
2058 if (end - buffer == 0)
2059 goto out_no_task;
2060
2061 ret = -ESRCH;
2062 task = get_proc_task(file->f_dentry->d_inode);
2063 if (!task)
2064 goto out_no_task;
2065
2066 ret = end - buffer;
2067 mm = get_task_mm(task);
2068 if (!mm)
2069 goto out_no_mm;
2070
2071 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2072 if (val & mask)
2073 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2074 else
2075 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2076 }
2077
2078 mmput(mm);
2079 out_no_mm:
2080 put_task_struct(task);
2081 out_no_task:
2082 return ret;
2083 }
2084
2085 static const struct file_operations proc_coredump_filter_operations = {
2086 .read = proc_coredump_filter_read,
2087 .write = proc_coredump_filter_write,
2088 };
2089 #endif
2090
2091 /*
2092 * /proc/self:
2093 */
2094 static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2095 int buflen)
2096 {
2097 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2098 pid_t tgid = task_tgid_nr_ns(current, ns);
2099 char tmp[PROC_NUMBUF];
2100 if (!tgid)
2101 return -ENOENT;
2102 sprintf(tmp, "%d", tgid);
2103 return vfs_readlink(dentry,buffer,buflen,tmp);
2104 }
2105
2106 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2107 {
2108 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
2109 pid_t tgid = task_tgid_nr_ns(current, ns);
2110 char tmp[PROC_NUMBUF];
2111 if (!tgid)
2112 return ERR_PTR(-ENOENT);
2113 sprintf(tmp, "%d", task_tgid_nr_ns(current, ns));
2114 return ERR_PTR(vfs_follow_link(nd,tmp));
2115 }
2116
2117 static const struct inode_operations proc_self_inode_operations = {
2118 .readlink = proc_self_readlink,
2119 .follow_link = proc_self_follow_link,
2120 };
2121
2122 /*
2123 * proc base
2124 *
2125 * These are the directory entries in the root directory of /proc
2126 * that properly belong to the /proc filesystem, as they describe
2127 * describe something that is process related.
2128 */
2129 static const struct pid_entry proc_base_stuff[] = {
2130 NOD("self", S_IFLNK|S_IRWXUGO,
2131 &proc_self_inode_operations, NULL, {}),
2132 };
2133
2134 /*
2135 * Exceptional case: normally we are not allowed to unhash a busy
2136 * directory. In this case, however, we can do it - no aliasing problems
2137 * due to the way we treat inodes.
2138 */
2139 static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
2140 {
2141 struct inode *inode = dentry->d_inode;
2142 struct task_struct *task = get_proc_task(inode);
2143 if (task) {
2144 put_task_struct(task);
2145 return 1;
2146 }
2147 d_drop(dentry);
2148 return 0;
2149 }
2150
2151 static struct dentry_operations proc_base_dentry_operations =
2152 {
2153 .d_revalidate = proc_base_revalidate,
2154 .d_delete = pid_delete_dentry,
2155 };
2156
2157 static struct dentry *proc_base_instantiate(struct inode *dir,
2158 struct dentry *dentry, struct task_struct *task, const void *ptr)
2159 {
2160 const struct pid_entry *p = ptr;
2161 struct inode *inode;
2162 struct proc_inode *ei;
2163 struct dentry *error = ERR_PTR(-EINVAL);
2164
2165 /* Allocate the inode */
2166 error = ERR_PTR(-ENOMEM);
2167 inode = new_inode(dir->i_sb);
2168 if (!inode)
2169 goto out;
2170
2171 /* Initialize the inode */
2172 ei = PROC_I(inode);
2173 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2174
2175 /*
2176 * grab the reference to the task.
2177 */
2178 ei->pid = get_task_pid(task, PIDTYPE_PID);
2179 if (!ei->pid)
2180 goto out_iput;
2181
2182 inode->i_uid = 0;
2183 inode->i_gid = 0;
2184 inode->i_mode = p->mode;
2185 if (S_ISDIR(inode->i_mode))
2186 inode->i_nlink = 2;
2187 if (S_ISLNK(inode->i_mode))
2188 inode->i_size = 64;
2189 if (p->iop)
2190 inode->i_op = p->iop;
2191 if (p->fop)
2192 inode->i_fop = p->fop;
2193 ei->op = p->op;
2194 dentry->d_op = &proc_base_dentry_operations;
2195 d_add(dentry, inode);
2196 error = NULL;
2197 out:
2198 return error;
2199 out_iput:
2200 iput(inode);
2201 goto out;
2202 }
2203
2204 static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2205 {
2206 struct dentry *error;
2207 struct task_struct *task = get_proc_task(dir);
2208 const struct pid_entry *p, *last;
2209
2210 error = ERR_PTR(-ENOENT);
2211
2212 if (!task)
2213 goto out_no_task;
2214
2215 /* Lookup the directory entry */
2216 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2217 for (p = proc_base_stuff; p <= last; p++) {
2218 if (p->len != dentry->d_name.len)
2219 continue;
2220 if (!memcmp(dentry->d_name.name, p->name, p->len))
2221 break;
2222 }
2223 if (p > last)
2224 goto out;
2225
2226 error = proc_base_instantiate(dir, dentry, task, p);
2227
2228 out:
2229 put_task_struct(task);
2230 out_no_task:
2231 return error;
2232 }
2233
2234 static int proc_base_fill_cache(struct file *filp, void *dirent,
2235 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
2236 {
2237 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2238 proc_base_instantiate, task, p);
2239 }
2240
2241 #ifdef CONFIG_TASK_IO_ACCOUNTING
2242 static int proc_pid_io_accounting(struct task_struct *task, char *buffer)
2243 {
2244 return sprintf(buffer,
2245 #ifdef CONFIG_TASK_XACCT
2246 "rchar: %llu\n"
2247 "wchar: %llu\n"
2248 "syscr: %llu\n"
2249 "syscw: %llu\n"
2250 #endif
2251 "read_bytes: %llu\n"
2252 "write_bytes: %llu\n"
2253 "cancelled_write_bytes: %llu\n",
2254 #ifdef CONFIG_TASK_XACCT
2255 (unsigned long long)task->rchar,
2256 (unsigned long long)task->wchar,
2257 (unsigned long long)task->syscr,
2258 (unsigned long long)task->syscw,
2259 #endif
2260 (unsigned long long)task->ioac.read_bytes,
2261 (unsigned long long)task->ioac.write_bytes,
2262 (unsigned long long)task->ioac.cancelled_write_bytes);
2263 }
2264 #endif
2265
2266 /*
2267 * Thread groups
2268 */
2269 static const struct file_operations proc_task_operations;
2270 static const struct inode_operations proc_task_inode_operations;
2271
2272 static const struct pid_entry tgid_base_stuff[] = {
2273 DIR("task", S_IRUGO|S_IXUGO, task),
2274 DIR("fd", S_IRUSR|S_IXUSR, fd),
2275 DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo),
2276 REG("environ", S_IRUSR, environ),
2277 INF("auxv", S_IRUSR, pid_auxv),
2278 ONE("status", S_IRUGO, pid_status),
2279 INF("limits", S_IRUSR, pid_limits),
2280 #ifdef CONFIG_SCHED_DEBUG
2281 REG("sched", S_IRUGO|S_IWUSR, pid_sched),
2282 #endif
2283 INF("cmdline", S_IRUGO, pid_cmdline),
2284 ONE("stat", S_IRUGO, tgid_stat),
2285 ONE("statm", S_IRUGO, pid_statm),
2286 REG("maps", S_IRUGO, maps),
2287 #ifdef CONFIG_NUMA
2288 REG("numa_maps", S_IRUGO, numa_maps),
2289 #endif
2290 REG("mem", S_IRUSR|S_IWUSR, mem),
2291 LNK("cwd", cwd),
2292 LNK("root", root),
2293 LNK("exe", exe),
2294 REG("mounts", S_IRUGO, mounts),
2295 REG("mountstats", S_IRUSR, mountstats),
2296 #ifdef CONFIG_PROC_PAGE_MONITOR
2297 REG("clear_refs", S_IWUSR, clear_refs),
2298 REG("smaps", S_IRUGO, smaps),
2299 REG("pagemap", S_IRUSR, pagemap),
2300 #endif
2301 #ifdef CONFIG_SECURITY
2302 DIR("attr", S_IRUGO|S_IXUGO, attr_dir),
2303 #endif
2304 #ifdef CONFIG_KALLSYMS
2305 INF("wchan", S_IRUGO, pid_wchan),
2306 #endif
2307 #ifdef CONFIG_SCHEDSTATS
2308 INF("schedstat", S_IRUGO, pid_schedstat),
2309 #endif
2310 #ifdef CONFIG_LATENCYTOP
2311 REG("latency", S_IRUGO, lstats),
2312 #endif
2313 #ifdef CONFIG_PROC_PID_CPUSET
2314 REG("cpuset", S_IRUGO, cpuset),
2315 #endif
2316 #ifdef CONFIG_CGROUPS
2317 REG("cgroup", S_IRUGO, cgroup),
2318 #endif
2319 INF("oom_score", S_IRUGO, oom_score),
2320 REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust),
2321 #ifdef CONFIG_AUDITSYSCALL
2322 REG("loginuid", S_IWUSR|S_IRUGO, loginuid),
2323 #endif
2324 #ifdef CONFIG_FAULT_INJECTION
2325 REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject),
2326 #endif
2327 #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
2328 REG("coredump_filter", S_IRUGO|S_IWUSR, coredump_filter),
2329 #endif
2330 #ifdef CONFIG_TASK_IO_ACCOUNTING
2331 INF("io", S_IRUGO, pid_io_accounting),
2332 #endif
2333 };
2334
2335 static int proc_tgid_base_readdir(struct file * filp,
2336 void * dirent, filldir_t filldir)
2337 {
2338 return proc_pident_readdir(filp,dirent,filldir,
2339 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
2340 }
2341
2342 static const struct file_operations proc_tgid_base_operations = {
2343 .read = generic_read_dir,
2344 .readdir = proc_tgid_base_readdir,
2345 };
2346
2347 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
2348 return proc_pident_lookup(dir, dentry,
2349 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
2350 }
2351
2352 static const struct inode_operations proc_tgid_base_inode_operations = {
2353 .lookup = proc_tgid_base_lookup,
2354 .getattr = pid_getattr,
2355 .setattr = proc_setattr,
2356 };
2357
2358 static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
2359 {
2360 struct dentry *dentry, *leader, *dir;
2361 char buf[PROC_NUMBUF];
2362 struct qstr name;
2363
2364 name.name = buf;
2365 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2366 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
2367 if (dentry) {
2368 if (!(current->flags & PF_EXITING))
2369 shrink_dcache_parent(dentry);
2370 d_drop(dentry);
2371 dput(dentry);
2372 }
2373
2374 if (tgid == 0)
2375 goto out;
2376
2377 name.name = buf;
2378 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2379 leader = d_hash_and_lookup(mnt->mnt_root, &name);
2380 if (!leader)
2381 goto out;
2382
2383 name.name = "task";
2384 name.len = strlen(name.name);
2385 dir = d_hash_and_lookup(leader, &name);
2386 if (!dir)
2387 goto out_put_leader;
2388
2389 name.name = buf;
2390 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2391 dentry = d_hash_and_lookup(dir, &name);
2392 if (dentry) {
2393 shrink_dcache_parent(dentry);
2394 d_drop(dentry);
2395 dput(dentry);
2396 }
2397
2398 dput(dir);
2399 out_put_leader:
2400 dput(leader);
2401 out:
2402 return;
2403 }
2404
2405 /**
2406 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2407 * @task: task that should be flushed.
2408 *
2409 * When flushing dentries from proc, one needs to flush them from global
2410 * proc (proc_mnt) and from all the namespaces' procs this task was seen
2411 * in. This call is supposed to do all of this job.
2412 *
2413 * Looks in the dcache for
2414 * /proc/@pid
2415 * /proc/@tgid/task/@pid
2416 * if either directory is present flushes it and all of it'ts children
2417 * from the dcache.
2418 *
2419 * It is safe and reasonable to cache /proc entries for a task until
2420 * that task exits. After that they just clog up the dcache with
2421 * useless entries, possibly causing useful dcache entries to be
2422 * flushed instead. This routine is proved to flush those useless
2423 * dcache entries at process exit time.
2424 *
2425 * NOTE: This routine is just an optimization so it does not guarantee
2426 * that no dcache entries will exist at process exit time it
2427 * just makes it very unlikely that any will persist.
2428 */
2429
2430 void proc_flush_task(struct task_struct *task)
2431 {
2432 int i;
2433 struct pid *pid, *tgid = NULL;
2434 struct upid *upid;
2435
2436 pid = task_pid(task);
2437 if (thread_group_leader(task))
2438 tgid = task_tgid(task);
2439
2440 for (i = 0; i <= pid->level; i++) {
2441 upid = &pid->numbers[i];
2442 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
2443 tgid ? tgid->numbers[i].nr : 0);
2444 }
2445
2446 upid = &pid->numbers[pid->level];
2447 if (upid->nr == 1)
2448 pid_ns_release_proc(upid->ns);
2449 }
2450
2451 static struct dentry *proc_pid_instantiate(struct inode *dir,
2452 struct dentry * dentry,
2453 struct task_struct *task, const void *ptr)
2454 {
2455 struct dentry *error = ERR_PTR(-ENOENT);
2456 struct inode *inode;
2457
2458 inode = proc_pid_make_inode(dir->i_sb, task);
2459 if (!inode)
2460 goto out;
2461
2462 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2463 inode->i_op = &proc_tgid_base_inode_operations;
2464 inode->i_fop = &proc_tgid_base_operations;
2465 inode->i_flags|=S_IMMUTABLE;
2466 inode->i_nlink = 5;
2467 #ifdef CONFIG_SECURITY
2468 inode->i_nlink += 1;
2469 #endif
2470
2471 dentry->d_op = &pid_dentry_operations;
2472
2473 d_add(dentry, inode);
2474 /* Close the race of the process dying before we return the dentry */
2475 if (pid_revalidate(dentry, NULL))
2476 error = NULL;
2477 out:
2478 return error;
2479 }
2480
2481 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2482 {
2483 struct dentry *result = ERR_PTR(-ENOENT);
2484 struct task_struct *task;
2485 unsigned tgid;
2486 struct pid_namespace *ns;
2487
2488 result = proc_base_lookup(dir, dentry);
2489 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
2490 goto out;
2491
2492 tgid = name_to_int(dentry);
2493 if (tgid == ~0U)
2494 goto out;
2495
2496 ns = dentry->d_sb->s_fs_info;
2497 rcu_read_lock();
2498 task = find_task_by_pid_ns(tgid, ns);
2499 if (task)
2500 get_task_struct(task);
2501 rcu_read_unlock();
2502 if (!task)
2503 goto out;
2504
2505 result = proc_pid_instantiate(dir, dentry, task, NULL);
2506 put_task_struct(task);
2507 out:
2508 return result;
2509 }
2510
2511 /*
2512 * Find the first task with tgid >= tgid
2513 *
2514 */
2515 struct tgid_iter {
2516 unsigned int tgid;
2517 struct task_struct *task;
2518 };
2519 static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
2520 {
2521 struct pid *pid;
2522
2523 if (iter.task)
2524 put_task_struct(iter.task);
2525 rcu_read_lock();
2526 retry:
2527 iter.task = NULL;
2528 pid = find_ge_pid(iter.tgid, ns);
2529 if (pid) {
2530 iter.tgid = pid_nr_ns(pid, ns);
2531 iter.task = pid_task(pid, PIDTYPE_PID);
2532 /* What we to know is if the pid we have find is the
2533 * pid of a thread_group_leader. Testing for task
2534 * being a thread_group_leader is the obvious thing
2535 * todo but there is a window when it fails, due to
2536 * the pid transfer logic in de_thread.
2537 *
2538 * So we perform the straight forward test of seeing
2539 * if the pid we have found is the pid of a thread
2540 * group leader, and don't worry if the task we have
2541 * found doesn't happen to be a thread group leader.
2542 * As we don't care in the case of readdir.
2543 */
2544 if (!iter.task || !has_group_leader_pid(iter.task)) {
2545 iter.tgid += 1;
2546 goto retry;
2547 }
2548 get_task_struct(iter.task);
2549 }
2550 rcu_read_unlock();
2551 return iter;
2552 }
2553
2554 #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
2555
2556 static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
2557 struct tgid_iter iter)
2558 {
2559 char name[PROC_NUMBUF];
2560 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
2561 return proc_fill_cache(filp, dirent, filldir, name, len,
2562 proc_pid_instantiate, iter.task, NULL);
2563 }
2564
2565 /* for the /proc/ directory itself, after non-process stuff has been done */
2566 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
2567 {
2568 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2569 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
2570 struct tgid_iter iter;
2571 struct pid_namespace *ns;
2572
2573 if (!reaper)
2574 goto out_no_task;
2575
2576 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
2577 const struct pid_entry *p = &proc_base_stuff[nr];
2578 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
2579 goto out;
2580 }
2581
2582 ns = filp->f_dentry->d_sb->s_fs_info;
2583 iter.task = NULL;
2584 iter.tgid = filp->f_pos - TGID_OFFSET;
2585 for (iter = next_tgid(ns, iter);
2586 iter.task;
2587 iter.tgid += 1, iter = next_tgid(ns, iter)) {
2588 filp->f_pos = iter.tgid + TGID_OFFSET;
2589 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
2590 put_task_struct(iter.task);
2591 goto out;
2592 }
2593 }
2594 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
2595 out:
2596 put_task_struct(reaper);
2597 out_no_task:
2598 return 0;
2599 }
2600
2601 /*
2602 * Tasks
2603 */
2604 static const struct pid_entry tid_base_stuff[] = {
2605 DIR("fd", S_IRUSR|S_IXUSR, fd),
2606 DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo),
2607 REG("environ", S_IRUSR, environ),
2608 INF("auxv", S_IRUSR, pid_auxv),
2609 ONE("status", S_IRUGO, pid_status),
2610 INF("limits", S_IRUSR, pid_limits),
2611 #ifdef CONFIG_SCHED_DEBUG
2612 REG("sched", S_IRUGO|S_IWUSR, pid_sched),
2613 #endif
2614 INF("cmdline", S_IRUGO, pid_cmdline),
2615 ONE("stat", S_IRUGO, tid_stat),
2616 ONE("statm", S_IRUGO, pid_statm),
2617 REG("maps", S_IRUGO, maps),
2618 #ifdef CONFIG_NUMA
2619 REG("numa_maps", S_IRUGO, numa_maps),
2620 #endif
2621 REG("mem", S_IRUSR|S_IWUSR, mem),
2622 LNK("cwd", cwd),
2623 LNK("root", root),
2624 LNK("exe", exe),
2625 REG("mounts", S_IRUGO, mounts),
2626 #ifdef CONFIG_PROC_PAGE_MONITOR
2627 REG("clear_refs", S_IWUSR, clear_refs),
2628 REG("smaps", S_IRUGO, smaps),
2629 REG("pagemap", S_IRUSR, pagemap),
2630 #endif
2631 #ifdef CONFIG_SECURITY
2632 DIR("attr", S_IRUGO|S_IXUGO, attr_dir),
2633 #endif
2634 #ifdef CONFIG_KALLSYMS
2635 INF("wchan", S_IRUGO, pid_wchan),
2636 #endif
2637 #ifdef CONFIG_SCHEDSTATS
2638 INF("schedstat", S_IRUGO, pid_schedstat),
2639 #endif
2640 #ifdef CONFIG_LATENCYTOP
2641 REG("latency", S_IRUGO, lstats),
2642 #endif
2643 #ifdef CONFIG_PROC_PID_CPUSET
2644 REG("cpuset", S_IRUGO, cpuset),
2645 #endif
2646 #ifdef CONFIG_CGROUPS
2647 REG("cgroup", S_IRUGO, cgroup),
2648 #endif
2649 INF("oom_score", S_IRUGO, oom_score),
2650 REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust),
2651 #ifdef CONFIG_AUDITSYSCALL
2652 REG("loginuid", S_IWUSR|S_IRUGO, loginuid),
2653 #endif
2654 #ifdef CONFIG_FAULT_INJECTION
2655 REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject),
2656 #endif
2657 };
2658
2659 static int proc_tid_base_readdir(struct file * filp,
2660 void * dirent, filldir_t filldir)
2661 {
2662 return proc_pident_readdir(filp,dirent,filldir,
2663 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
2664 }
2665
2666 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
2667 return proc_pident_lookup(dir, dentry,
2668 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
2669 }
2670
2671 static const struct file_operations proc_tid_base_operations = {
2672 .read = generic_read_dir,
2673 .readdir = proc_tid_base_readdir,
2674 };
2675
2676 static const struct inode_operations proc_tid_base_inode_operations = {
2677 .lookup = proc_tid_base_lookup,
2678 .getattr = pid_getattr,
2679 .setattr = proc_setattr,
2680 };
2681
2682 static struct dentry *proc_task_instantiate(struct inode *dir,
2683 struct dentry *dentry, struct task_struct *task, const void *ptr)
2684 {
2685 struct dentry *error = ERR_PTR(-ENOENT);
2686 struct inode *inode;
2687 inode = proc_pid_make_inode(dir->i_sb, task);
2688
2689 if (!inode)
2690 goto out;
2691 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2692 inode->i_op = &proc_tid_base_inode_operations;
2693 inode->i_fop = &proc_tid_base_operations;
2694 inode->i_flags|=S_IMMUTABLE;
2695 inode->i_nlink = 4;
2696 #ifdef CONFIG_SECURITY
2697 inode->i_nlink += 1;
2698 #endif
2699
2700 dentry->d_op = &pid_dentry_operations;
2701
2702 d_add(dentry, inode);
2703 /* Close the race of the process dying before we return the dentry */
2704 if (pid_revalidate(dentry, NULL))
2705 error = NULL;
2706 out:
2707 return error;
2708 }
2709
2710 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2711 {
2712 struct dentry *result = ERR_PTR(-ENOENT);
2713 struct task_struct *task;
2714 struct task_struct *leader = get_proc_task(dir);
2715 unsigned tid;
2716 struct pid_namespace *ns;
2717
2718 if (!leader)
2719 goto out_no_task;
2720
2721 tid = name_to_int(dentry);
2722 if (tid == ~0U)
2723 goto out;
2724
2725 ns = dentry->d_sb->s_fs_info;
2726 rcu_read_lock();
2727 task = find_task_by_pid_ns(tid, ns);
2728 if (task)
2729 get_task_struct(task);
2730 rcu_read_unlock();
2731 if (!task)
2732 goto out;
2733 if (!same_thread_group(leader, task))
2734 goto out_drop_task;
2735
2736 result = proc_task_instantiate(dir, dentry, task, NULL);
2737 out_drop_task:
2738 put_task_struct(task);
2739 out:
2740 put_task_struct(leader);
2741 out_no_task:
2742 return result;
2743 }
2744
2745 /*
2746 * Find the first tid of a thread group to return to user space.
2747 *
2748 * Usually this is just the thread group leader, but if the users
2749 * buffer was too small or there was a seek into the middle of the
2750 * directory we have more work todo.
2751 *
2752 * In the case of a short read we start with find_task_by_pid.
2753 *
2754 * In the case of a seek we start with the leader and walk nr
2755 * threads past it.
2756 */
2757 static struct task_struct *first_tid(struct task_struct *leader,
2758 int tid, int nr, struct pid_namespace *ns)
2759 {
2760 struct task_struct *pos;
2761
2762 rcu_read_lock();
2763 /* Attempt to start with the pid of a thread */
2764 if (tid && (nr > 0)) {
2765 pos = find_task_by_pid_ns(tid, ns);
2766 if (pos && (pos->group_leader == leader))
2767 goto found;
2768 }
2769
2770 /* If nr exceeds the number of threads there is nothing todo */
2771 pos = NULL;
2772 if (nr && nr >= get_nr_threads(leader))
2773 goto out;
2774
2775 /* If we haven't found our starting place yet start
2776 * with the leader and walk nr threads forward.
2777 */
2778 for (pos = leader; nr > 0; --nr) {
2779 pos = next_thread(pos);
2780 if (pos == leader) {
2781 pos = NULL;
2782 goto out;
2783 }
2784 }
2785 found:
2786 get_task_struct(pos);
2787 out:
2788 rcu_read_unlock();
2789 return pos;
2790 }
2791
2792 /*
2793 * Find the next thread in the thread list.
2794 * Return NULL if there is an error or no next thread.
2795 *
2796 * The reference to the input task_struct is released.
2797 */
2798 static struct task_struct *next_tid(struct task_struct *start)
2799 {
2800 struct task_struct *pos = NULL;
2801 rcu_read_lock();
2802 if (pid_alive(start)) {
2803 pos = next_thread(start);
2804 if (thread_group_leader(pos))
2805 pos = NULL;
2806 else
2807 get_task_struct(pos);
2808 }
2809 rcu_read_unlock();
2810 put_task_struct(start);
2811 return pos;
2812 }
2813
2814 static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
2815 struct task_struct *task, int tid)
2816 {
2817 char name[PROC_NUMBUF];
2818 int len = snprintf(name, sizeof(name), "%d", tid);
2819 return proc_fill_cache(filp, dirent, filldir, name, len,
2820 proc_task_instantiate, task, NULL);
2821 }
2822
2823 /* for the /proc/TGID/task/ directories */
2824 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
2825 {
2826 struct dentry *dentry = filp->f_path.dentry;
2827 struct inode *inode = dentry->d_inode;
2828 struct task_struct *leader = NULL;
2829 struct task_struct *task;
2830 int retval = -ENOENT;
2831 ino_t ino;
2832 int tid;
2833 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */
2834 struct pid_namespace *ns;
2835
2836 task = get_proc_task(inode);
2837 if (!task)
2838 goto out_no_task;
2839 rcu_read_lock();
2840 if (pid_alive(task)) {
2841 leader = task->group_leader;
2842 get_task_struct(leader);
2843 }
2844 rcu_read_unlock();
2845 put_task_struct(task);
2846 if (!leader)
2847 goto out_no_task;
2848 retval = 0;
2849
2850 switch (pos) {
2851 case 0:
2852 ino = inode->i_ino;
2853 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0)
2854 goto out;
2855 pos++;
2856 /* fall through */
2857 case 1:
2858 ino = parent_ino(dentry);
2859 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0)
2860 goto out;
2861 pos++;
2862 /* fall through */
2863 }
2864
2865 /* f_version caches the tgid value that the last readdir call couldn't
2866 * return. lseek aka telldir automagically resets f_version to 0.
2867 */
2868 ns = filp->f_dentry->d_sb->s_fs_info;
2869 tid = (int)filp->f_version;
2870 filp->f_version = 0;
2871 for (task = first_tid(leader, tid, pos - 2, ns);
2872 task;
2873 task = next_tid(task), pos++) {
2874 tid = task_pid_nr_ns(task, ns);
2875 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
2876 /* returning this tgid failed, save it as the first
2877 * pid for the next readir call */
2878 filp->f_version = (u64)tid;
2879 put_task_struct(task);
2880 break;
2881 }
2882 }
2883 out:
2884 filp->f_pos = pos;
2885 put_task_struct(leader);
2886 out_no_task:
2887 return retval;
2888 }
2889
2890 static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
2891 {
2892 struct inode *inode = dentry->d_inode;
2893 struct task_struct *p = get_proc_task(inode);
2894 generic_fillattr(inode, stat);
2895
2896 if (p) {
2897 rcu_read_lock();
2898 stat->nlink += get_nr_threads(p);
2899 rcu_read_unlock();
2900 put_task_struct(p);
2901 }
2902
2903 return 0;
2904 }
2905
2906 static const struct inode_operations proc_task_inode_operations = {
2907 .lookup = proc_task_lookup,
2908 .getattr = proc_task_getattr,
2909 .setattr = proc_setattr,
2910 };
2911
2912 static const struct file_operations proc_task_operations = {
2913 .read = generic_read_dir,
2914 .readdir = proc_task_readdir,
2915 };
WRT350N Kernel Patches